ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The impact of nitrogen fertilization of tomato on feeding site selection and oviposition by Trialeurodes vaporariorum (1998)
    Springer
    Entomologia experimentalis et applicata 86 (1998), S. 175-182 
    Details
    ISSN: 1570-7458
    Keywords: Aleyrodidae ; greenhouse whitefly ; nitrogen ; host selection ; oviposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tomato plants, Lycopersicon esculentum Miller cv 'Tres Cantos', were supplied with high (308 ppm), medium (140 ppm) and low (84 ppm) nitrogen doses in order to determine the influence of nitrogen fertilization on feeding and oviposition site selection by greenhouse whitefly adults, T. vaporariorum (Westwood). The nitrogen and water content was higher in plants supplied with 308 N ppm than in plants with medium or low nitrogen doses and no differences were found in soluble sugar content. The leaves of the upper plant stratum (leaves 1–5) had the greatest nitrogen and water content, independent of the nitrogen dose applied. The plants were exposed to T. vaporariorum adults into a greenhouse under two current (late autumn-winter and spring-early summer) situations of the tomato crop in the Mediterranean area. The distribution of whitefly adults on the plants was affected by the nitrogen dose in both experimental conditions, the number of adults was higher on the plants supplied with high nitrogen dose. Within plants, adult distribution was affected by leaf position, the upper plant stratum being preferred for feeding. Whitefly females selected for oviposition and laid more eggs on plants and leaves of plants with higher nitrogen and water contents. We conclude that whitefly host selection for feeding and ovipositing are related to differences in nitrogen and water content of the host plant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003145813704
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Fecundity and egg distribution of the herbivore Spodoptera pectinicornis as influenced by quality of the floating aquatic plant Pistia stratiotes (1998)
    Springer
    Entomologia experimentalis et applicata 86 (1998), S. 295-304 
    Details
    ISSN: 1570-7458
    Keywords: fecundity ; host plant quality ; Pistia stratiotes ; Spodoptera pectinicornis ; nitrogen ; trichomes ; oviposition ; biological control of weeds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We determined the influence of larval host quality of the floating aquatic weed Pistia stratiotes L. (Araceae) on the fecundity and egg distribution of the biological control agent Spodoptera pectinicornis (Hampson) (Lepidoptera: Noctuidae). Different nutritional levels were produced by growing plants with relatively low and high levels of nitrogen, phosphorus and potassium fertilizer. Female and male pupal biomass were significantly greater when the larvae were fed leaves from the high fertilizer plants. Although the fertilizer treatments did not significantly influence total fecundity, there was an indirect effect as adults from larger pupae were more fecund. Regardless of treatment, ovipositing females formed a depression in the leaf surface by removing trichomes into which they deposited the egg masses. Most of the egg masses were laid on the lower leaf surface, on leaf positions 5–8 (counting from the young inner to the outer leaves) and during days 1–2 post-eclosion. Most of the eggs were laid in masses but about 12% were solitary. Females fed the low fertilizer treatment laid a greater proportion (mean ± s.e.) of their eggs as solitary eggs (17.3 ± 3.4% of total eggs) than did females fed the high fertilizer treatment (8.3 ± 2.3% of total eggs). The increased percentage of solitary eggs laid by the females from the low quality larval diet may be an adaptive response to decrease competition among the progeny.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003193220069
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The effect of nitrogen fertilizer applied to Euphorbia pulcherrima on the parasitization of Bemisia argentifolii by the parasitoid Encarsia formosa (1996)
    Springer
    Entomologia experimentalis et applicata 78 (1996), S. 105-110 
    Details
    ISSN: 1570-7458
    Keywords: Bemisia argentifolii ; Encarsia formosa ; poinsettia ; parasitoids ; nitrogen ; tri-trophic level interactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract More wasps of Encarsia formosa Gahan (Hymenoptera: Aphelinidae) were found on fertilized poinsettias, Euphorbia pulcherrima (Willd.) (Euphorbiaceae), than on non-fertilized plants. Parasitization of Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae) by E. formosa was higher on plants treated with calcium nitrate than with ammonium nitrate or on control plants. In a no-choice test, host feeding by E. formosa was higher when hosts were on fertilized plants than when hosts were on control plants. The nitrogen content of whitefly pupae reared on plants treated with ammonium nitrate was higher than those on calcium nitrate-treated plants. Variability in the parasitization of B. argentifolii by E. formosa appears to be due to host plant-mediated differences in the whiteflies. E. formosa may be influenced by the nutritional suitability of the host, which influences whether wasps continue to oviposit, feed, or disperse.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304461
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Plant growth stage effects on the feeding and growth responses of the bertha armyworm,Mamestra configurata to canola and mustard foliage (1995)
    Springer
    Entomologia experimentalis et applicata 74 (1995), S. 55-61 
    Details
    ISSN: 1570-7458
    Keywords: Brassica rapa ; B. juncea ; consumption rate ; glucosinolates ; growth rate ; indolyl ; isothiocyanate ; Mamestra configurata ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Mamestra configurata (Walker) (Lep., Noctuidae) larvae were fed excisedBrassica juncea (commercial brown mustard) orB. rapa cv. Tobin (Canola) foliage of three plant growth stages-rosette (stage 2), stem elongation (stage 3) and flowering (stage 4). Relative consumption rates (RCRi) were not significantly different between the plant species. Within theB. juncea treatments, there were no significant growth stage differences in RCRi. However, withinB. rapa, RCRi increased with advancing plant growth stage. Larvae fedB. juncea foliage had significantly reduced relative growth rates (RGRi) compared to larvae fedB. rapa foliage. Within theB. juncea treatments, RGRi decreased with advancing plant growth stage. There were no significant growth stage differences in RGRi in theB. rapa treatments. RGRi was inversely proportional to the levels of isothiocyanate-releasing glucosinolates in theB. juncea treatments. RCRi was inversely proportional to the levels of indolyl glucosinolates in theB. rapa treatments. Levels of total phenols and catechols inB. juncea did not show any trend which could be related to growth stage effects in the insect nutritional indices. InB. rapa, levels of phenols and catechols in stage 3 and 4 foliage were lower than that of stage 2 foliage. Analyses of total nitrogen in field-grown plants showed reductions in percent nitrogen from rosette to flowering stage foliage. The response ofM. configurata to different growth stages of its host plants are discussed in relation to changing levels of allelochemicals and nitrogen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02383167
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Compensatory responses of Samea multiplicalis larvae when fed leaves of different fertilization levels of the aquatic weed Pistia stratiotes (1999)
    Springer
    Entomologia experimentalis et applicata 92 (1999), S. 205-216 
    Details
    ISSN: 1570-7458
    Keywords: Samea multiplicalis ; Spodoptera pectinicornis ; Pistia stratiotes ; waterlettuce ; nitrogen utilization efficiency ; compensatory feeding ; nitrogen ; biological control of weeds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Compensatory responses of caterpillars fed low quality food include increased consumption and utilization of essential nutrients. Information about an insect's responses to nutritional challenges from their host plants could benefit weed biological control efforts in the selection and establishment of new agents. The target weed, Pistia stratiotes L. (Araceae) is a floating aquatic plant that has relatively low nitrogen levels which are further diluted with high water content. Efforts to establish the insect Spodoptera pectinicornis (Hampson) (Lepidoptera: Noctuidae) for biological control of P. stratiotes could benefit by examining the nutritional responses of a similar widely established lepidopteran species, Samea multiplicalis (Guenèe) (Lepidoptera: Pyralidae). Larvae of this species were fed leaves of P. stratiotes plants that had been fertilized (NPK) at high and low rates. The leaves of the fertilized plants had a 4.3-fold increase in nitrogen (dry weight) and a 1.6-fold increase in water content. The results suggest that no compensatory increases occurred in larvae fed leaves from the low fertilized plants as no changes were found in fresh mass consumption or nitrogen utilization efficiency. Consequently, development time from second-third instars to pupation was delayed about 3 days compared with larvae fed the high nitrogen leaves. Furthermore, consumption of nitrogen was only 30% and its accumulation into larval tissues was only 60% compared with the larvae fed the high fertilized leaves. The resulting larvae had both a final biomass and a growth rate that were reduced by 40%. Regardless of plant fertilizer level, the larvae fed at a rate 5–10 times greater than that of similar lepidopteran species consuming either low or high quality diets, suggesting that the S. multiplicalis larvae may be functioning at their biological limit for ingesting food.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003771512722
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Comparative effect of short term exposures of Callosobruchus subinnotatus to carbon dioxide, nitrogen, or low temperature on behavior and fecundity (1998)
    Springer
    Entomologia experimentalis et applicata 89 (1998), S. 243-248 
    Details
    ISSN: 1570-7458
    Keywords: Coleoptera ; bruchidae ; anesthesia ; carbon dioxide ; nitrogen ; cold ; oviposition and mating
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of anesthetizing with carbon dioxide, nitrogen, or low temperature on the reproductive behavior and fecundity of Callosobruchus subinnotatus was investigated. Males and females anesthetized with N2 as virgins had shorter recovery time, copulated earlier, and had shorter mating time than those subjected to CO2 or low temperature. Exposure of males and females to 2.0±0.5 °C for 10 min had the most profound effect on the recovery periods, copulation time, and duration of mating. Adults anesthetized with CO2 and low temperature laid fewer eggs than those anesthetized with N2. Females were more affected than males by the treatments, except when males were chilled for 10 min, and this prolonged the time for commencement of mating. The mode of anesthesia could affect egg production because vitellogenesis and choriogenesis take place in the imago stage of bruchids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003503623654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The effect of stem and cob borers on maize subjected to different nitrogen treatments (1995)
    Springer
    Entomologia experimentalis et applicata 77 (1995), S. 205-210 
    Details
    ISSN: 1570-7458
    Keywords: nitrogen ; maize ; lepidopterous stem and cob borers ; Sesamia calamistis ; Eldana saccharina ; Mussidia nigrivenella ; Cryptophlebia leucotreta ; dead hearts ; stem tunneling ; yields
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of four nitrogen levels (0, 60, 90 and 120 kg N/ha) on growth of maize and development of lepidopterous pests was investigatdd in a field trial. Nitrogen had a positive effect on both plant growth variables (plant height, stem diameter and yield), and development and survival ofSesamia calamistis andEldana saccharina, and thereby increased the incidence of dead hearts and stem tunneling. However, the percent yield loss due to artificial infestation decreased with increasing N application rate from 20% to 11% in the in the 0kg/ha and 120kg/ha treatment, respectively. Using a multiple regression analysis, plant height, plant diameter and stem tunneling were found to be the most important variables explaining the variability in maize yield.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02383035
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Plant quality or quantity? Host exploitation strategies in three Chrysomelidae species associated with Asteraceae host plants (1999)
    Springer
    Entomologia experimentalis et applicata 92 (1999), S. 165-177 
    Details
    ISSN: 1570-7458
    Keywords: Chrysomelidae ; herbivory ; Asteraceae ; life history ; nitrogen ; plant quality ; season
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phytophagous insects which feed on the leaves of herbaceous host plants have to adapt their life histories to the fact that protein nitrogen is usually highest in growing tissues in spring. We monitored field populations of larvae and adults of three chrysomelid species (Galeruca tanaceti (L.) (main host Achillea millefolium (L.) Yarrow), Cassida rubiginosa (Mueller) (main host Cirsium arvense (L.) Scop.) and Oreina luctuosa (Suffrian) (host Centaurea scabiosa (L.)) together with the amount of protein nitrogen of their food resources and host plant biomass. As expected, the development of host quality, measured as concentration of protein nitrogen, and host plant biomass showed inverse trends during the season. The euryphagous G. tanaceti attacks Achillea early and profits from high nitrogen concentrations in the leaves. Occasional overexploitations of local populations of Achillea are compensated by the capacity to move to other host species. In C. rubiginosa, a species with a host range restricted to the Cardueae, the main larval feeding activity is postponed to a period when the nitrogen content of the host leaves had dropped to 50% of its initial value, but when host plant biomass had increased by 30%. In the monophagous O. luctuosa the larval development is synchronized with a still later phase of host phenology, at which the nitrogen content is below 50% but plant biomass has reached its maximum. There seem to be selection factors, which oppose the use of high quality food in spring and which force the latter two species to postpone their larval development to a later time in the year. This could be caused by numerous factors like, for example, mean daytime temperature. Later in the season the larvae have to cope with the low quality of their host plants. They have, however, the advantage of large quantities of food available. A laboratory study with adults and mature larvae of O. luctuosa shows that this species can overcome low levels of protein nitrogen either by selecting younger leaves with higher nitrogen concentrations or by increasing the daily food consumption rate (RCR) on leaves with a low level of nitrogen and by a prolongation of the feeding period. In this way the larvae compensate the effect of lower daily growth rates (RGR) and a lower food conversion index (ECI) on poor food quality: Regardless of the level of protein nitrogen there was no statistically significant difference in total gain of weight during the third-instar feeding period and in the weight at the end of the third larval stage. The three investigated chrysomelids show that there exists a broad spectrum of adaptations to overcome the dilemma of variable food quality.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003709622409
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effects of cosolvents cetyltrimethylammonium bromide on the thresholds for nucleation of nitrogen in aqueous solutions (1995)
    Springer
    Journal of solution chemistry 24 (1995), S. 1059-1073 
    Details
    ISSN: 1572-8927
    Keywords: Supersaturation ; nitrogen ; cosolvent ; cetyltrimethylammonium bromide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The decomposition of ammonium nitrite in water creates a supersaturated solution of nitrogen. The same process occurs in water-organic solvent mixtures. Acetone, dioxane, dimethylsulfoxide (DMSO) and dimethylformamide (DMF) are the cosolvents used in this study. The limits of supersaturation of nitrogen (C SL /mol L−1) were determined in all of these solvent mixtures by releasing the dissolved gas sonicationally and measuring the volume of released gas. C SL was generally increased in the presence of cosolvents. The effectiveness sequence of organic solvents was found to be as DMF〈DMSO〈Dioxanet≅Acetone. Transportation period of small bubbles formed during sonication is changed by compositions of solvent mixtures. These periods may depend on the viscosity of the solution. Effects of the presence of cetyltrimethylammonium bromide were also studied. It was concluded that there may be a relation between the strength of the watercosolvent H-bonds and C SL and all of the measured quantities of this study were generally affected by micelle formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00973522
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Open-Air Litter Foraging in the Nasute Termite Longipeditermes longipes (Isoptera: Termitidae) (1998)
    Springer
    Journal of insect behavior 11 (1998), S. 179-189 
    Details
    ISSN: 1572-8889
    Keywords: open-air foraging ; caste ; polyethism ; litter feeder ; nitrogen ; termite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Southeast Asian nasute termite Longipeditermes longipes forages on the open ground on leaf litter. Its monomorphic workers carry back food balls in their mandibles while dimorphic soldiers defensively surround the marching columns and the foraging patches. When mechanically disturbed, workers hide under the litter, whereas antennating soldiers face as closely as possible the source of disturbance. Foragers prefer the lower, nitrogen-rich layer of the litter. Soldier behavior and column organization (returning workers in the center lanes, outgoing workers in the two flanking lanes) are similar to those in the related genera Hospitalitermes and Lacessititermes, which, however, tend to forage above ground.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021039722402
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Simulation of kinetics of nitrogen desorption from Rh(111) (1996)
    Springer
    Catalysis letters 37 (1996), S. 163-165 
    Details
    ISSN: 1572-879X
    Keywords: nitrogen ; Rh(111) ; thermal desorption ; Arrhenius parameters ; lateral interactions ; NO decomposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Associative desorption of N atoms from the Rh(111) surface is simulated in the framework of the lattice-gas model. The Arrhenius parameters and nearest-neighbour lateral interaction employed to describe the measured thermal desorption spectra are as follows:v=1013 s−1,E d=40 kcal/mol, and ε1=1.7 kcal/mol. The results obtained are used to clarify the role of nitrogen desorption in the NO + CO reaction on Rh(111) atT=400–700 K andP NO≈P CO≈0.01 atm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807748
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Transglutaminase induction by various cell death and apoptosis pathways (1996)
    Springer
    Cellular and molecular life sciences 52 (1996), S. 942-949 
    Details
    ISSN: 1420-9071
    Keywords: Apoptosis ; transglutaminase ; signalling ; gene expression ; promoter elements ; retinoic acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Clarification of the molecular details of forms of natural cell death, including apoptosis, has become one of the most challenging issues of contemporary biomedical sciences. One of the effector elements of various cell death pathways is the covalent cross-linking of cellular proteins by transglutaminases. This review will discuss the accumulating data related to the induction and regulation of these enzymes, particularly of tissue type transglutaminase, in the molecular program of cell death. A wide range of signalling pathways can lead to the parallel induction of apoptosis and transglutaminase, providing a handle for better understanding the exact molecular interactions responsible for the mechanism of regulated cell death.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01920102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Analysis of gene function inDictyostelium (1995)
    Springer
    Cellular and molecular life sciences 51 (1995), S. 1116-1123 
    Details
    ISSN: 1420-9071
    Keywords: Antisense RNA ; gene expression ; insertional mutagenesis ; physical mapping ; reporter genes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Over the past ten years, powerful molecular genetic techniques have been developed to analyze gene function inDictyostelium. DNA-mediated transformation using a variety of selections and vectors has allowed the introduction of wild-type or modified genes that are under various forms of transcriptional control. Homologous recombination is efficient and can be used to modify the genome in precise ways. In addition, it is now possible to clone genes based on their mutant phenotype alone, either by insertional mutagenesis, or by screening antisense expression cDNA libraries. Finally, a nearly complete physical map of the genome is available and so genes are easily mapped by physical techniques. We discuss many of these advances within the context of major research problems presently under study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01944729
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Regulation of metallothionein gene expression in Cd- or Zn-adapted RK-13 cells (1995)
    Springer
    Cellular and molecular life sciences 51 (1995), S. 606-611 
    Details
    ISSN: 1420-9071
    Keywords: Metallothionein ; isometallothioneins ; gene expression ; rabbit kidney cell-line ; cadmium adaptation ; zinc adaptation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We explored the molecular genetics underlying the massive induction of isoMTs by Zn2+ or Cd2+ in metal tolerant rabbit kidney (RK-13) sub-line cells, using band shift assays and Southern blotting analysis. In sub-line cells accommodated to intermediate metal concentrations (100 μM Zn2+; 1–20 μM Cd2+) evidence suggested that the increase in the capacity for isoMT synthesis is brought about by an increased binding activity of the nuclear transcription factors MTF-1 and Sp1. Using quantitative band shift analysis with a mouse MRE-d oligonucleotide probe, the binding of both transcription factors was found to be enhanced two to three times over the binding activity measured in the unexposed parental RK-13 cells. Their increase in binding activity is probably the cause of the overexpression of MT genes and the development of metal tolerance in these cells. In cells tolerant to the highest concentrations of metal the analysis of Southern blot signals revealed MT gene amplification to be the most probable cause of the increased MT production. Thus, in cells of sub-lines growing in the presence of 350 μM Zn2+, two of the isoMT genes were coordinately triplicated and in cells tolerant to 150 μM Cd2+ one isoMT gene was amplified two-fold.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02128753
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    FTIR spectroscopic evidence of formation of geminal dinitrogen species during the low-temperature N2 adsorption on NaY zeolites (1999)
    Springer
    Catalysis letters 58 (1999), S. 21-26 
    Details
    ISSN: 1572-879X
    Keywords: adsorption ; adsorption isotherms ; dinitrogen ; FTIR spectroscopy ; geminal species ; NaY ; nitrogen ; zeolites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Adsorption of N2 on NaY zeolites at 85 K and equilibrium pressures higher than 1 kPa results in the formation of geminal dinitrogen complexes characterized by an IR band at 2333.5 cm−1 (2255.4 cm−1 after adsorption of 15N2). With decreasing equilibrium pressure the complexes tend to loose one N2 ligand, thus forming linear species characterized by an IR band at 2336.8 cm−1 (2258.7 cm−1 after adsorption of 15N2). All species disappear completely after evacuation. Co-adsorption of N2 and CO revealed that the dinitrogen complexes are formed on Na+ cations. The changes in the concentrations of the linear and geminal N2 species with the changes in the equilibrium pressure are excellently described by equations of adsorption isotherms proposed earlier for mono- and di-carbonyls.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019040825491
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Nuclear calcium: a key regulator of gene expression (1998)
    Springer
    BioMetals 11 (1998), S. 345-358 
    Details
    ISSN: 1572-8773
    Keywords: calcium ; CREB ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Through the evolution of multicellular organisms, calcium has emerged as the preferred ion for intracel-lular signalling. It now occupies a pivotal role in many cell types and nowhere is it more important than in neurons, where it mediates both the relaying and long-term storage of information. The latter is a process that enables learning and memory to be formed and requires the activation of gene expression by calcium signals. Evidence from a number of diverse organisms shows that transcription mediated by the transcrip-tion factor CREB is critical for learning and memory. Here we review the features of CREB activation by calcium signals in mammalian cells. In contrast to other transcription factors, its regulation is dependent on an elevation of nuclear calcium concentration, potentially placing this spatially distinct pool of calcium as an important mediator of information storage.© Kluwer Academic Publishers
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009257909785
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Pure and Binary Gas Adsorption Equilibria and Kinetics of Methane and Nitrogen on 4A Zeolite by Isotope Exchange Technique (1999)
    Springer
    Adsorption 5 (1999), S. 145-158 
    Details
    ISSN: 1572-8757
    Keywords: kinetics ; isotope-exchange ; nitrogen ; adsorption ; methane ; zeolite ; equilibria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The Isotope Exchange Technique (IET) was used to simultaneously measure pure and binary gas adsorption equilibria and kinetics (self-diffusivities) of CH4 and N2 on pelletized 4A zeolite. The experiment was carried out isothermally without disturbing the adsorbed phase. CH4 was selectively adsorbed over N2 by the zeolite because of its higher polarizability. The multi-site Langmuir model described the pure gas and binary adsorption equilibria fairly well at three different temperatures. The selectivity of adsorption of CH4 over N2 increased with increasing pressure at constant gas phase composition and temperature. This curious behavior was caused by the differences in the sizes of the adsorbates. The diffusion of CH4 and N2 into the zeolite was an activated process and the Fickian diffusion model described the uptake of both pure gases and their mixtures. The self-diffusivity of N2 was an order of magnitude larger than that for CH4. The pure gas self-diffusivities for both components were constants over a large range of surface coverages (0 〈 θ 〈 0.5). The self-diffusivities of CH4 and N2 from their binary mixtures were not affected by the presence of each other, compared to their pure gas self-diffusivities at identical surface coverages.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008917308002
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Two kinds of adsorbed N atoms with different reactivities with H2 on a Pt0.25Rh0.75(100) surface (1998)
    Springer
    Catalysis letters 52 (1998), S. 151-155 
    Details
    ISSN: 1572-879X
    Keywords: platinum ; rhodium ; alloy ; surface composition ; nitrogen ; oxygen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Two kinds of adsorbed N atoms exist on a Pt0.25Rh0.75(100) surface. One desorbs at 490 K and the other desorbs at 650 K. The former reacts with H2 at 400 K, but the latter does not. It is supposed that the adsorption of these two N atoms is responsible of the surface composition, ratio of Pt and Rh.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019000326574
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Management-induced change in labile soil organic matter under continuous corn in eastern Canadian soils (1997)
    Springer
    Biology and fertility of soils 26 (1997), S. 88-94 
    Details
    ISSN: 1432-0789
    Keywords: Key words Microbial biomass C ; Water-soluble organic carbon ; Light fraction organic carbon ; Fertilizer ; nitrogen ; 13C nuclear magnetic resonance ; Infrared spectrophotometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Soil samples taken from four experimental sites that had been cropped to continuous corn for 3–11 years in Ontario and Quebec were analyzed to evaluate changes in quantity and quality of labile soil organic carbon under different nitrogen (N) fertility and tillage treatments. Addition of fertilizer N above soil test recommendations tended to decrease amounts of water-soluble organic carbon (WSOC) and microbial biomass carbon (MBC). The quality of the WSOC was characterized by 13C nuclear magnetic resonance and infrared spectrophotometry and the results indicated that carbohydrates, long-chain aliphatics and proteins were the major components of all extracts. Similar types of C were present in all of the soils, but an influence of management was evident. The quantity of soil MBC was positively related to the quantities of WSOC, carbohydrate C, and organic C, and negatively related to quantities of long-chain aliphatic C in the soil. The quantity of WSOC was positively related to the quantities of protein C, carbohydrate C, and negatively related to the quantity of carboxylic C. The quantity of soil MBC was not only related to quantities of soil WSOC but also to the quality of soil WSOC.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003740050348
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Nitrogen uptake and growth of two citrus rootstock seedlings in a sandy soil receiving different controlled-release fertilizer sources (1998)
    Springer
    Biology and fertility of soils 26 (1998), S. 169-172 
    Details
    ISSN: 1432-0789
    Keywords: Key words Urea ; Coated fertilizers ; Ammonium ; nitrogen ; Nitrate nitrogen ; Nitrogen uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Understanding the fate of different forms of nitrogen (N) fertilizers applied to soils is an important step in enhancing N use efficiency and minimizing N losses. The growth and N uptake of two citrus rootstocks, Swingle citrumelo (SC), and Cleopatra mandarin (CM), seedlings were evaluated in a pot experiment using a Candler fine sand (hyperthermic, uncoated, Typic Quartzipsamments) without N application or with 400 mg N kg–1 applied as urea or controlled-release fertilizers (CRF; either as Meister, Osmocote, or Poly-S). Meister and Osmocote are polyolefin resin-coated urea with longevity of N release for 270 days (at 25°C). Poly-S is a polymer and sulfur-coated urea with release duration considerably shorter than that of either Meister or Osmocote. The concentrations of 2 M KCl extractable nitrate nitrogen (NO3 –-N) and ammonium nitrogen (NH4 +-N) in the soil sampled 180 days and 300 days after planting were greater in the soil with SC than with CM rootstock seedlings. In most cases, the extractable NH4 + and NO3 – concentrations were greater for the Osmocote treatment compared to the other N sources. For the SC rootstock seedlings, dry weight was greater with Meister or Poly-S compared with either Osmocote or urea. At the end of the experiment, ranking of the various N sources, with respect to total N uptake by the seedlings, was: Meister = Osmocote 〉 Poly-S 〉 Urea 〉 no N for CM rootstock, and Meister = Poly-S = Osmocote 〉 Urea 〉 no N for SC rootstock. The study demonstrated that for a given rate of N application the total N uptake by seedlings was greater for the CRF compared to urea treatment. This suggests that various N losses were lower from the CRF source as compared to those from soluble fertilizers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003740050363
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Microbial contribution to extractable N and P after air-drying of dry tropical soils (1997)
    Springer
    Biology and fertility of soils 26 (1997), S. 31-34 
    Details
    ISSN: 1432-0789
    Keywords: Key words Microbial biomass ; Air-drying ; Extractable ; nitrogen ; Extractable phosphorus ; Tropical soil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The microbial contribution to extractable N and P after the air-drying of eight Indian dry tropical Ultisols was quantified. Air-drying of the soils decreased microbial biomass C by 25–53% but increased extractable N and P by 14–34% and 24–121%, respectively. This increase in the extractable N and P was accounted for, to some extent, by microbial biomass killed due to air-drying. Microbial biomass contributes 17–36% and 19–82% to the extractable N and P, respectively, possibly due to air-drying of the soils. I conclude that due to contamination of microbial biomass with the available nutrients in air-dried soils, measurements of extractable nutrients should be made on field-moist soils.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003740050339
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    AES investigations of the iron surface composition after laser irradiation under atmospheric conditions (1998)
    Springer
    Microchimica acta 130 (1998), S. 89-95 
    Details
    ISSN: 1436-5073
    Keywords: AES ; laser ; iron ; nitrogen ; oxygen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The laser induced modification of iron surfaces with atmospheric species was investigated by means of Auger electron spectroscopy (AES) and scanning electron microscopy (SEM). Different laser systems were used for irradiating iron samples in a wide range of the laser processing parameters up to small foci and ultra short pulses. A nitriding of iron connected with an oxidation of the near surface region was observed in the wavelength range between 193 nm and 10.6 μm using large foci (∼0.1 cm2) and short pulses (10...1400ns). In case of small foci (∼7·10−6cm2) with ns-pulses (50 ns) an enrichment of the iron melt with nitrogen and an advanced oxidation of the surrounding area of the laser spot were detected. When using shorter pulses (200 fs, 40 ps) no indications for a nitriding were found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01254595
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Multiplex Titration RT-PCR: Rapid Determination of Gene Expression Patterns for a Large Number of Genes (1998)
    Springer
    Plant molecular biology reporter 16 (1998), S. 323-339 
    Details
    ISSN: 1572-9818
    Keywords: Aux/IAA genes ; gene expression ; gene families ; RT-PCR ; tomato
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have developed an improved method for determination of gene expression levels with RT-PCR. The procedure is rapid and does not require extensive optimization or densitometric analysis. Since the detection of individual transcripts is PCR-based, small amounts of tissue samples are sufficient for the analysis of expression patterns in large gene families. Using this method, we were able to rapidly screen nine members of the Aux/IAA family of auxin- responsive genes and identify those genes which vary in message abundance in a tissue- and light-specific manner. While not offering the accuracy of conventional semi-quantitative or competitive RT-PCR, our method allows quick screening of large numbers of genes in a wide range of RNA samples with just a thermal cycler and standard gel analysis equipment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007523305132
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Isolation of RNA and Protein from Guard Cells of Nicotiana glauca (1999)
    Springer
    Plant molecular biology reporter 17 (1999), S. 371-383 
    Details
    ISSN: 1572-9818
    Keywords: epidermal peel ; extraction ; gene expression ; stomata ; tree tobacco
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Stomatal guard cells are critical for maintenance of plant homeostasis and represent an interesting cell type for studies of leaf cell differentiation and patterning. Here we describe techniques for the isolation of guard cell RNA and protein from blended epidermal peels of Nicotiana glauca. The RNA isolation procedure is a modification of the hot borate method, which is particularly well-suited for recalcitrant tissues. Protein was extracted by disrupting guard cell-enriched epidermis with a French® press. This system offers the following advantages: relatively high yield, low or no contamination by other cell types, fresh tissue as a source of RNA and protein rather than protoplasts, and a plant species that is readily transformable. These techniques will allow for cloning and analysis of genes expressed in guard cells, application of traditional biochemical techniques to guard cell proteins, as well as characterization of genetic manipulation of guard cell function in transgenic plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007602017492
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Forms and nature of organic N in soil (1995)
    Springer
    Nutrient cycling in agroecosystems 42 (1995), S. 1-11 
    Details
    ISSN: 1573-0867
    Keywords: nitrogen ; 15N humic substances ; acid hydrolysis ; analytical pyrolysis ; NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Most of the N in surface soils occurs in organic forms. The organic N in soil plays a key role in plant nutrition and soil fertility through its effects on microbial activity and nutrient availability. Typically, about one-third of the fertilizer N applied to temperate-zone soils is immobilized and retained in organic forms at the end of the growing season. A significant portion of this newly immobilized N is no more available to microorganisms and plants than the native humus N. Stabilization processes, probably involving polymerization of amino compounds and polyphenols, result in incorporation of N into humic substances with a concurrent reduction in N availability. This paper presents an account of the forms and nature of organic N in soil, emphasizing possible formation pathways, chemical characterization of humic substances through conventional and solid-state techniques, and the fate and composition of newly immobilized N in soil.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00750495
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    A conceptual assessment of the importance of denitrification as a source of soil nitrogen loss in tropical agro-ecosystems (1995)
    Springer
    Nutrient cycling in agroecosystems 42 (1995), S. 139-148 
    Details
    ISSN: 1573-0867
    Keywords: denitrification ; methods ; 15N ; nitrate ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract This paper attempts to answer the question: is denitrification a major route of N loss from tropical agro-ecosystems? This question turns out to be very difficult to answer due to a severe shortage of data on this process for tropical agro-ecosystems other than rice. Given this lack of data, I approach this question by analyzing data on denitrification and nitrous oxide flux in tropical native forest and pasture soils and attempt to make some conclusions and pose some hypotheses about the significance of denitrification in tropical agricultural soils. I also briefly review methods for measuring denitrification. The data analysis suggests that denitrification in tropical forest soils is strongly influenced by the nature and amount of soil C and N turnover. Studies to examine differences in denitrification in different tropical agricultural systems should focus on the effects of system management on C and N turnover. The data analysis also suggests that, just as in temperate regions, denitrification may not be a significant route of N loss from most tropical agricultural systems. However, field studies are necessary to determine if this is actually the case.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00750508
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Estimating nutrient surplus and nutrient use efficiency from farm characteristics (1995)
    Springer
    Nutrient cycling in agroecosystems 45 (1995), S. 221-233 
    Details
    ISSN: 1573-0867
    Keywords: fertilizer recovery ; modelling ; nitrogen ; nutrient efficiency ; nutrient surplus ; phosphorus ; Poland
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Research on nutrient losses from agricultural systems should try to relate these losses to farm characteristics. This was done for private farms in two districts in Poland. Using data from a farm survey, nutrient surpluses and Nutrient Use Efficiency (NUE, defined as the ratio of outgoing and incoming nutrients) were calculated for nitrogen and phosphorus. Both nutrient surplus and NUE are relatively high. A model was developed to estimate surpluses and NUE from farm characteristics like location, farm size, fertilizer application level, animal density, grass production and sugar beet or potato area. The results of the model are satisfying for nutrient surplus (R2=0.9) and nitrogen NUE (R2=0.4). Estimation of phosphorus NUE was not satisfactory. High surpluses are associated with high fertilizer applications, high animal density and high grass production while an increasing share of sugar beets leads to lower surpluses. A high nitrogen NUE is associated with low fertilizer applications, low animal density and little grass production, and with a high sugar beet area share. Results suggest that, with exception of sugar beet, fertilizer recovery in Poland is very low. Sugar beet, however, combines high fertilizer applications with low surpluses and high NUE. The outcome of the model can be used in the design of environmental policies. The paper ends with some remarks on the type of measures that can be taken, and the effects these will have on private farms in Poland.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00748593
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Influence of co-granulated nutrients and granule size on plant responses to elemental sulfur in compound fertilizers (1996)
    Springer
    Nutrient cycling in agroecosystems 46 (1996), S. 81-90 
    Details
    ISSN: 1573-0867
    Keywords: elemental sulfur ; granule size ; nitrogen ; phosphorus ; potassium ; S oxidation ; sulfur fertilizers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Experiments were undertaken to determine the effect of granule size and nutrients in granulated compound fertilizers fortified with finely divided elemental sulfur (So) on the rate of So oxidation. In one experiment, So was banded together with or apart from triple superphosphate (TSP) while in two others, So was granulated with nutrient and inert carriers. A fourth experiment examined response to S in an So-fortified TSP from a range of granule sizes. Response and, in some cases, So recovery (using 35S labels) by test crops (maize, wheat, upland rice) was measured. In all experiments, P mixed with So increased plant growth and S recovery above treatments in which P and So were physically separated. There was however, no effect of distance of separation on S recovery. In one experiment, N as urea and N and P as diammonium phosphate (DAP) were also found to enhance response to So although to a lesser degree than P alone. These observations were attributed to a nutritional requirement of So-oxidizing microorganisms for P and N. Granulation of So with carriers also influenced oxidation rate, as inferred from the fertilizer S recovery. For a given So concentration, the effect was inversely proportional to the mean diameter of granules. It is shown that this relationship can be explained if one assumes that So particles in granules collapse into a fixed number of aggregates per granule irrespective of granule size when the soluble nutrient carrier dissolves and diffuses away from the point of application.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210226
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Direct emission of nitrous oxide from agricultural soils (1996)
    Springer
    Nutrient cycling in agroecosystems 46 (1996), S. 53-70 
    Details
    ISSN: 1573-0867
    Keywords: crop ; emission ; fertilizer ; nitrogen ; nitrous oxide ; soil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract This analysis is based on published measurements of nitrous oxide (N2O) emission from fertilized and unfertilized fields. Data was selected in order to evaluate the importance of factors that regulate N2O production, including soil conditions, type of crop, nitrogen (N) fertilizer type and soil and crop management. Reported N2O losses from anhydrous ammonia and organic N fertilizers or combinations of organic and synthetic N fertilizers are higher than those for other types of N fertilizer. However, the range of management and environmental conditions represented by the data set is inadequate for use in estimating emission factors for each fertilizer type. The data are appropriate for estimating the order of magnitude of emissions. The longer the period over which measurements are made, the higher the fertilizer-induced emission. Therefore, a simple equation to relate the total annual direct N2O−N emission (E) from fertilized fields to the N fertilizer applied (F), was based on the measurements covering periods of one year: E=1+1.25×F, with E and F in kg N ha-1 yr-1. This relationship is independent of the type of fertilizer. Although the above regression equation includes considerable uncertainty, it may be appropriate for global estimates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210224
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Effects of temperature on nutrient release from slow-release fertilizers (1996)
    Springer
    Nutrient cycling in agroecosystems 46 (1996), S. 179-187 
    Details
    ISSN: 1573-0867
    Keywords: electrical conductivity ; leaching ; nitrogen ; pH ; phosphorus ; potassium ; release pattern ; slow-release fertilizers ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract We studied the effect of temperature on the release of N, P, and K from slow-release fertilizers (SRF). The study was conducted in micro-lysimeters filled with moist peat medium. Increasing the temperature from 4 to 12°C slightly increased N release from three different slow-release N (SRN) carriers with different particle sizes and coating thicknesses. At 21°C the rate of release was significantly different than the other two temperatures. Urea formaldehyde (UF), sulphur coated urea (SCU) and coated calcium nitrate (CCN), incubated in sphagnum moss peat, released between 3 and 20% of the applied N in six weeks. For eight synthetic and organic NPK carriers, the release pattern was similar to UF and SCU. However, the leaching losses of N from the NPK fertilizers were up to twenty times more than for the SRN products. Except for Osmocote® and Duna, which released 30–40% of the applied N as mineral-N within six weeks, all other slow-release and slowly mineralized NPK carriers acted like readily water-soluble compound NPK. Temperature did not affect the nutrient release from NPK fertilizers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00420552
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Evaluation of nitrate leaching risk at site and farm level (1998)
    Springer
    Nutrient cycling in agroecosystems 50 (1998), S. 271-276 
    Details
    ISSN: 1573-0867
    Keywords: nitrogen ; monitoring ; dairy farming ; simulation models ; risk assessment ; soil variability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract At the ‘De Marke’ experimental farm a dairy farm was set up with the aim of meeting environmental and economic goals. The farm management with respect to nitrogen emphasized reduction of fertilization and a cattle grazing system that should result in nitrate concentrations in the groundwater below the EC-directive level of 11.3 mg l-1 nitrate-N. At six sites in six different fields of ‘De Marke’, these concentrations were monitored for 4 years. A direct comparison with the chosen limit was possible for these sites, but an evaluation of the environmental achievements of the farming system at farm level was also required. This was achieved by using simulation models and additional information about soils and field management. Based on multiple soil profile descriptions, frequency distributions of model output were generated, allowing a risk assessment for the total farm. The probability of exceeding the chosen threshold value of 11.3 mg l-1 nitrate-N during the period of summer 1991- spring 1995 was 63% for the whole farm, with marked differences between years, crops and hydrological conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009704714949
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Leaching of nitrogen and phosphorus from rural areas to surface waters in the Netherlands (1998)
    Springer
    Nutrient cycling in agroecosystems 50 (1998), S. 321-324 
    Details
    ISSN: 1573-0867
    Keywords: nutrient modelling ; leaching ; nitrogen ; phosphorus ; schematization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In context of preparing the Fourth National Policy Document on Water Management in the Netherlands effects of different scenarios of fertilizer management on nitrogen (N) and phosphorus (P) leaching from rural areas into Dutch surface waters were analyzed. The manuscript offers insight into the model instrument that is used to simulate the different scenarios. Main parts of the modelinstrument are: a procedure to schematize the Netherlands in horizontal areal units, field scale mechanistic models for water and nutrient behaviour in the soil and an empirical model for fertilizer additions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009773202654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Can organic farming help to reduce N-losses? (1998)
    Springer
    Nutrient cycling in agroecosystems 52 (1998), S. 277-287 
    Details
    ISSN: 1573-0867
    Keywords: dairy farming ; efficiency ; nitrogen ; organic ; pig farming ; surplus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract This study is in two parts. In the first part, nitrogen (N) losses per unit of milk and meat in Danish conventional and organic pig and dairy farming were compared on the basis of farm data. In the second part, organic and conventional dairy farming were compared in detail, using modelling. N-surpluses at different livestock densities, fodder intensities, and soil types were simulated. Finally, simulated N-surpluses were used in national scenarios for conversion to organic dairy farming in Denmark. In Part one, pig farming was found to have a higher N-efficiency than dairy farming. Organic pig production had a lower N-efficiency and a higher N-surplus per kg meat than conventional pig production. The possibilities to reduce N-loss by conversion to organic pig production therefore appear to be poor. Organic dairy farming had a higher N-efficiency and a lower N-surplus per kg milk than conventional dairy farming. Conversion from conventional to organic dairy farming may therefore reduce N-losses. In Part two, a positive correlation between livestock density and N-surplus ha-1 was found for dairy farming. For all simulated livestock densities, fodder feeding intensities and soil types, organic systems showed a lower N-surplus per unit of milk produced than conventional systems. National scenarios for dairy farming showed that the present Danish milk production could be achieved with a 24% lower total N-surplus if converted from intensive conventional farming to extensive organic farming. At the same time, N-surplus ha-1 and N-surplus (t milk)-1 would be lowered by 50% and 25% respectively. Changing from intensive to extensive conventional dairy farming with a livestock density equal to that in the organic scenario resulted in a reduction in N-surplus ha-1 of 15%. It was concluded that a reduction in total N-loss from agriculture is possible by converting from conventional to organic dairy farming but at the cost of either lower production on the present dairy farm area, or the current production on a substantially larger area.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009790722044
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Food production and consumption in Germany: N flows and N emissions (1998)
    Springer
    Nutrient cycling in agroecosystems 52 (1998), S. 289-301 
    Details
    ISSN: 1573-0867
    Keywords: food production and consumption ; mitigation strategies ; nitrogen ; nitrogen emission ; nitrous oxide ; sustainability of human N cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract During the past four decades the authors perceive that an increasing non-sustainability (Disintegration) within the agriculture , human nutrition, waste management complex has occurred both in Germany and the European Union. Compared to the basic needs of the population for nutritive energy, fat and protein, we estimate that the production and consumption of food and feed is more than 50% higher than necessary. Using nitrogen (N) input into German agriculture in 1991/92 as an example, we estimated that the N input of 191 kg ha-1 was 2 to 3 times too high. This high N input resulted in the net biomass production of 45 kg ha-1, a 25% efficiency. This inefficiency causes emissions of reactive N and other nutrient compounds into the hydrosphere and atmosphere that were 2 to 8 times too high. For example the contributions of agriculture to the total annual N2O–N emissions of Germany (during 1990–1992), Europe (1990) and of the world (1989) were 110, 691 Gg and 6.7 Tg or 52, 62 and 41%, respectively. The authors demonstrate that emissions of N and P from Germany and EU waste water management systems are also higher than necessary because nutrient recycling is not practiced extensively. Excessive food production and consumption has made the agriculture/human nutrition/waste and waste water complex, like the energy/transportation complex, a main cause of new transboundary environmental damage such as soil and water acidification, hypertrophication of near-natural terrestrial and aquatic ecosystems and climate change. We propose that a sustainable food production/consumption system can be developed that is based both on need-oriented production and consumption with no net exports and on recovery, recycling and more efficient use of nutrients. Using N as an example, the authors show which short and long term action aims must be set and realized by the year 2015, to meet environmental, economical and social sustainability requisites. The suggested, assumed sustainable N balance for German agriculture is characterized by a critical annual input and surplus maximum of 80 and 45 kg N ha-1 respectively, which should almost double biomass production efficiency for N utilization. This estimate is based on reducing animal stocking rates to 0.5 gross weight unit ha-1 to attain no net mineralization or immobilization of N in the soil.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009706001900
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Retention and leaching of N in Norwegian coniferous forests (1998)
    Springer
    Nutrient cycling in agroecosystems 52 (1998), S. 171-178 
    Details
    ISSN: 1573-0867
    Keywords: atmospheric deposition ; boreal forests ; critical loads ; forest growth ; gas losses ; leaching ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Nitrogen is brought into natural ecosystems from the atmosphere through N-fixation and deposition of NH 4 + and NO 3 - as wet and dry deposition. N is lost from terrestrial ecosystems unaffected by human activities by leaching or as gas, but the losses from different forest-and vegetation types are poorly quantified. The leaching is hampered by uptake in the vegetation and by immobilisation by soil organisms. The gas loss of N in the form of N2O and N2 appears to be rather small, but the loss of NO is unknown. Human activities such as those leading to the increased atmospheric dry and wet deposition of N, may affect the N-losses, but the increase in losses are likely to be very dependent on the amounts of N deposited. The present paper discusses the fate of the N deposited under the existing pollution climate in Norway where N deposition above the natural background has taken place for at least 50 years. The deposition today varies from about 15–20 kg N ha-1 yr-1 in the southernmost parts of the country to background values of about 2 kg ha-1 yr-1 in the north. Even in areas with the highest loads there are no clear indications that N-leaching in forest ecosystems has increased to ‘unacceptable’ levels. The main reason for this appears to be that most of the N deposited are immobilised in forest soils and utilised by forest trees and ground cover vegetation to increased biomass production. At present therefore, no clear signs of N-saturation can be found. This is in relatively good accordance with estimates of critical loads for N in Norwegian coniferous forests. Estimates of immobilisation, gas losses, net uptake in vegetation, biological fixation as well as a figure for ‘acceptable’ leaching, indicate that the long-term critical load of N might be of the order 10 to 30 kg N ha-1 yr-1. Most of the N deposited from the atmosphere appears therefore so far to be retained in the forests and only a small proportion seems to be lost to ground-and surface waters.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009715027516
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Effect of split applications of cattle slurry and mineral fertilizer–N on the yield of silage maize in a slurry-based cropping system (1999)
    Springer
    Nutrient cycling in agroecosystems 53 (1999), S. 209-218 
    Details
    ISSN: 1573-0867
    Keywords: cattle slurry ; fertilizer splitting ; nitrogen ; recovery ; residual nitrogen ; Zea mays L
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The recovery of soil mineral nitrogen (N) by crops, and its subsequent utilisation for dry matter (DM) production may be increased when the application of N is postponed until after crop emergence. The significance of this strategy for silage maize was studied in nine field experiments on Dutch sandy soils from 1983 to 1988. In five experiments the effect of slurry applied before planting at a rate of circa 66 m3 ha-1, was compared to the effect of a similar rate of which half was applied before planting and half at the 4–6 leaf stage. In the 4-6 leaf stage slurry was either injected or banded. In four other experiments the effect of mineral fertilizer-N splitting was studied. In these experiments, 30 m3 ha-1 cattle slurry, applied before planting, was supplemented with mineral fertilizer-N at rates ranging from 40 to 160 kg ha-1, either fully applied before crop emergence or split. When split, 40 kg ha-1 of the mineral fertilizer-N rate was banded at the 4–6 leaf stage. According to balance sheet calculations, substantial losses of slurry N and mineral fertilizer-N occurred during the growing season. Losses were compensated for, however, by apparent mineralization, ranging from 0.34 to 0.77 kg N ha-1 day-1. Split applications of cattle slurry had a significant positive effect on the DM yield in two out of five experiments compared to the conventional non-split application, but only when the post-emergence slurry application was banded which is no longer in accordance with present legislation. Split applications of mineral fertilizer-N had a significant positive effect in one experiment where rainfall was excessive but not in the others. The results provide insufficient evidence to recommend farmers to split applications. Soil mineral N sampling at the 4–6 leaf stage should hence be considered a control on the appropriateness of early N applications after exceptional weather conditions rather than a routine observation on which the post-emergence N dressing is to be based in a deliberate splitting strategy. Our data suggest that the financial return of a 40 kg ha-1 supplementation with mineral fertilizer-N, was questionable when more than 175 kg N ha-1 were found in the upper 0.6 m soil layer at the 4–6 leaf stage.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009796021850
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Using nitrogen budgets to indicate nitrogen use efficiency and losses from whole farm systems: a comparison of three methodological approaches (1999)
    Springer
    Nutrient cycling in agroecosystems 53 (1999), S. 259-267 
    Details
    ISSN: 1573-0867
    Keywords: farming systems ; nitrogen ; nitrogen budgets ; sustainability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Three approaches to nitrogen budgeting were developed and their ability to quantitatively describe nitrogen cycling in a fertilizer based and a grass–clover based beef system tested. Budgets ranged in complexity from the Economic Input:Output (EIO) budget, which accounted simply for purchases and sales of nitrogen over the farmgate, through the Biological Input:Output (BIO) budget, which included estimates of biological nitrogen fixation and attempted to partition losses into leaching and gaseous forms, to the Transfer:Recycle:Input:Output (TRIO) budget, which also accounted for key soil processes. Nitrogen unaccounted for in the fertilized system decreased with increasing budget complexity (285, 212 and 188 kg ha-1 yr-1 unaccounted for by the EIO, BIO and TRIO budgets, respectively). In the legume based grass–clover system, the EIO budget did not accurately describe total nitrogen inputs as it did not include 146 kg ha-1 yr-1 from symbiotic nitrogen fixation. In the grass–clover system, nitrogen unaccounted for was again greater using the BIO than the TRIO budget (103 and 79 kg ha-1 yr-1, respectively). In conclusion, the most complex budgeting approach (TRIO) was able to account for the fate of a greater proportion of nitrogen inputs than the simpler approaches. However, the perceived success of the different approaches was strongly dependent on the precise objective.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009793120577
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Nitrogen uptake and chlorophyll meter measurements in Spring Wheat (1999)
    Springer
    Nutrient cycling in agroecosystems 55 (1999), S. 1-6 
    Details
    ISSN: 1573-0867
    Keywords: chlorophyll meter ; irrigation ; LAI ; nitrogen ; Spring Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A Spring Wheat crop was grown using three irrigation levels and nitrogen rate applications to evaluate chlorophyll meter measurements as a possible nitrogen nutrition index for modelling. These measurements yielded the most reliable indications at Zadoks GS45. The lower limit indicating severe nitrogen deficiency in the leaves was approximately 35 SPAD units while the upper limit of 45 SPAD units, indicated an excess consumption.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009843813004
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    The fate of algal nitrogen in a flooded soil system (1999)
    Springer
    Nutrient cycling in agroecosystems 55 (1999), S. 89-94 
    Details
    ISSN: 1573-0867
    Keywords: algae ; flooded soils ; N cycling ; nitrogen ; 15N ; rice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Algal N labelled with 15N added to a flooded soil in laboratory columns without plants was studied to determine the changes over time in the fate of N assimilated by algae and to study how its fate is affected by (a) exclusion of light simulating complete closure of the rice canopy, and (b) addition of fertilizer-NH4 *. In the light but with no added fertilizer-N there was little net mineralization of the added algal N during the first 4 weeks, but after 8 weeks 42% had been mineralized, of which 95% was denitrified. Exclusion of light caused net mineralization to proceed more rapidly in the first 4 weeks due to the death of algal cells and lowered reassimilation. After 8 weeks 51% had been mineralized, of which 54% was denitrified, 16% volatilized and 30% was present as KCl exchangeable NH4 +-N. Application of fertilizer-NH4 + apparently caused mineralization of 25% of the algal N within one week but the results were probably affected by pool substitution in which labelled N mineralized to NH4 +-N was diluted with fertilizer – NH+ 4 and then immobilized leaving more labelled NH4–N in the mineral pool. After 8 weeks, 42% of algal N had been mineralized, of which 69% was estimated to have been denitrified, 19% lost through NH3 volatilization and 12% remained as extracted NH4 ++NO- 3. Uptake of N by a rice crop would reduce the gaseous losses. Algal N was mineralized quickly enough to be available during the growing season of a rice crop and, depending on field conditions, algae may have a role in assimilating N and protecting it from loss as well as being a major driving force for NH3 volatilization through diurnal increases in pH.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009850915579
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    15N isotope dilution techniques to study soil nitrogen transformations and plant uptake (1995)
    Springer
    Nutrient cycling in agroecosystems 42 (1995), S. 185-192 
    Details
    ISSN: 1573-0867
    Keywords: 15N ; nitrogen ; soil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The use of15N as a tracer in soil/plant research is examined. The limitations of the so-called Ndff approach are discussed to show the need to consider not just the fate of the added label but also the path that was followed and the rate of the transformation. The development of15N isotope dilution techniques to determine gross rates of nitrogen transformation in soil is reviewed with some indications as to the further development of the approach.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00750513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    The value of poultry manure for wetland rice grown in rotation with wheat (1996)
    Springer
    Nutrient cycling in agroecosystems 47 (1996), S. 243-250 
    Details
    ISSN: 1573-0867
    Keywords: fertilizer value ; nitrogen ; phosphorus ; poultry manure ; urea ; wetland rice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Poultry manure applied alone or in combination with urea at different N levels was evaluated as a N source for wetland rice grown in a Fatehpur loamy sand soil. Residual effects were studied on wheat which followed rice every year during the three cropping cycles. In the first year, poultry manure did not perform better than urea but by the third year, when applied in quantities sufficient to supply 120 and 180 kg N ha−1, it produced significantly more rice grain yield than the same rates of N as urea. Poultry manure sustained the grain yield of rice during the three years while the yield decreased with urea. Apparent N recovery by rice decreased from 45 to 28% during 1987 to 1989 in the case of urea, but it remained almost the same (35, 33 and 37%) for poultry manure. Thus, urea N values of poultry manure calculated from yield or N uptake data following two different approaches averaged 80, 112 and 127% in 1987, 1988 and 1989, respectively. Poultry manure and urea applied in 1:1 ratio on N basis produced yields in between the yields from the two sources applied alone. After three cycles of rice-wheat rotation, the organic matter in the soil increased with the amount of manure applied to a plot. Olsen available P increased in soils amended with poultry manure. A residual effect of poultry manure applied to rice to supply 120 or 180 kg N ha−1 was observed in the wheat which followed rice and it was equivalent to 40 kg N ha−1 plus some P applied directly to wheat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01986279
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Effect of digested sewage sludge on the efficiency of N-fertilizer applied to barley (1997)
    Springer
    Nutrient cycling in agroecosystems 48 (1997), S. 241-246 
    Details
    ISSN: 1573-0867
    Keywords: barley ; denitrification ; fertilizerefficiency ; mineralization ; nitrogen ; sludge
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Enhanced microbial activity following sewage sludge land application may affect soil N cycling and, therefore, plant available N. We studied the effect of anaerobically treated sewage sludge on N-fertilizer efficiency and on some aspects of the soil N cycling. Field plots (3 m × 9 m) sown with barley (Hordeum vulgare L.) in November were amended with a) sludge (80 mg ha-1) and ammonium nitrate (150 kg N ha-1), b) ammonium nitrate (150 kg ha-1) only, c) or left unamended. Monthly soil samples were taken from 0 to 20-and 20 to 50-cm depths to determine soil inorganic N (NH4 +, NO3-). Denitrification in the upper 20-cm horizon was estimated by measuring N2O+N2 emission from undisturbed soil samples by the acetylene-inhibition technique. Crop yield parameters were analysed before harvesting, and grain production was recorded. With respect to the control, the yield increase for the N-fertilizer treatment was 85% and 45% for the sludge + N-fertilizer treatment. The decrease of N-fertilizer efficiency in sludge amended plots was presumably due to a decrease in spring plant available N. Presumably, microbial immobilisation and denitrification in organic amended treatments were responsible for the decrease in N-fertilizer efficiency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009798509654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Impact of vesicular arbuscular mycorrhizal fungi andRhizobium on the growth and P, N and Fe uptake by faba-bean (1995)
    Springer
    Nutrient cycling in agroecosystems 43 (1995), S. 43-48 
    Details
    ISSN: 1573-0867
    Keywords: Phosphorus ; nitrogen ; iron ; VAM ; Rhizobium ; faba-bean
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effect of rhizobial inoculation, vesicular arbuscular mycorrhizal (VAM) fungi on the growth, P, N and Fe uptake by faba-bean plants (Vicia faba L.V. Giza 2) grown in virgin sandy soil, treated with super or rock-P were studied under green-house conditions. The earthern pots received a half of the recommended rate of P either as single super phosphate or rock-P in the rate of 20 mg P/kg soil, and calcium ammonium nitrate was added in the rate of 10 mg N/kg soil. Iron was applied in two levels 0 and 5 mg Fe/kg soil, in the form of iron sulphate (FeSO4·7H2O). Dry matter yield, as well as P, N and Fe-uptake were determined. Nodule numbers and their dry weights, spore numbers and mycorrhizal root infection were determined. Results indicated that, fungal infection and rhizobial inoculation either alone or in combination increased dry matter yield as compared to uninoculated plants, whereas the percentages increase in dry matter were 34, 26 and 57% in case of super-P application, while they were 56, 47 and 89% in case of rock-P when inoculated withRhizobium, VAM and dual inoculation respectively. Also P, N and Fe uptake were significantly increased due to inoculation, and dual inoculation resulted the highest effect. Generally, inoculation withRhizobium and/or mycorrhizae can remove the deficient effect of P and Fe on N2-fixation and plant growth in the soil of low nutrients content.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00747681
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    A global inventory of nitric oxide emissions from soils (1997)
    Springer
    Nutrient cycling in agroecosystems 48 (1997), S. 37-50 
    Details
    ISSN: 1573-0867
    Keywords: greenhouse gases ; nitrogen ; NOx ; nitrous oxide ; ozone precursors ; trace gases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Over 60 published papers reporting field measurements of emissions of nitric oxide (NO) from soil are reviewed, and over 100 annual estimates of NO emissions were made for various types of ecosystems, including agricultural fields. These data were stratified by biome and the mean of each stratum was multiplied by an estimate of the biome area. A few strata were identified as clearly having low NO emissions: montane forests, swamps and marshes, tundra, and temperate forests that are not heavily affected by N deposition. The largest emissions were observed in tropical savanna/woodland, chaparral, and cultivated agriculture, but variation in NO emissions within these strata was also large. Although the stratification scheme fails to partition this within-stratum variation, it does clearly identify these biomes as globally important sources of NO and as areas where more research is needed to investigate within-biome variation in NO emissions. It is too early to tell whether differences in NO emissions between temperate and tropical agriculture are significant, but it is clear that agriculture is an important source of NO and that management practices affect NO emissions. The best current estimate of the global soil source of NO is 21 Tg N yr-1. Adsorption of NOx onto plant canopy surfaces may reduce emissions to the atmosphere to as low as 13 Tg N yr-1, although the absorption effect is probably smaller than this. An error term for the global estimate is difficult to determine, but it is at least ±4 and perhaps as large at ±10 Tg N yr-1. Hence, only modest progress has been made in narrowing uncertainties in the estimate of the global soil source of NO, although some published lower estimates appear unlikely. This inventory reconfirms that the soil source of NO is similar in magnitude to fossil fuel emissions of NOx. Further narrowing of the uncertainty of the estimate of global soil NO emissions will require more sophisticated and carefully chosen stratification schemes to address variation within biomes based on soil fertility, soil texture, climate, and management and will require linking this type of inventory and stratification with mechanistic models.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009738715891
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Intercropping sorghum with nitrogen fixing trees in semiarid India (1998)
    Springer
    Agroforestry systems 42 (1998), S. 181-194 
    Details
    ISSN: 1572-9680
    Keywords: Acacia ferruginea ; Albizia lebbeck ; Faidherbia albida ; nitrogen ; sorghum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The influence of three nitrogen fixing tree (NFT) species viz., Faidherbia albida, Acacia ferruginea, Albizia lebbeck and four nitrogen levels (0, 20, 40 and 60 kg N ha−1) on intercropped rainfed sorghum was investigated at Hyderabad, India. The trees were established in shallow alfisols during 1985 with a spacing of 4 × 4 m. Intercropping was done in 1993 and 1994. The effect of trees on radiation interception, soil moisture, crop growth, yield components and yield of sorghum was examined. Association of tree species reduced grain and dryfodder yields of sorghum to an extent of 12 to 40% compared to sole crop situation. The reduction was maximum under A. lebbeck, minimum with F. albida and moderate under A. ferruginea. Application of 40 kg N ha−1 resulted in increased grain and dryfodder yields over other levels. Crop growth in terms of LAI and drymatter had similar response. The receipt of photosynthetically active radiation (PAR) was low under NFTs compared to open situation. The relative PAR intercepted under the trees was in the order: F. albida 〉 A. ferruginea 〉 A. lebbeck. Soil moisture status was more favourable under F. albida than under the other tree species. Soil moisture at all stages of crop growth was more in sole crop situation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006154725098
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Relationships between preference, rumen degradability, gas production and chemical composition of browses (1997)
    Springer
    Agroforestry systems 39 (1997), S. 129-144 
    Details
    ISSN: 1572-9680
    Keywords: fibre ; intake ; nitrogen ; palatability ; tannin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The aim of this work was to assess whether degradability, gas production or chemical constituents could predict the preference of browses. Forty tropical browse species leaves with a crude protein (CP) content ranging from 79 to 307 g kg-1 DM were used for this study. The neutral detergent fibre (NDF) ranged from 220 to 694 g kg-1 DM, while acid detergent fibre (ADF) ranged from 146 to 523 g kg-1 DM. The NDF-bound nitrogen (NDFN) and ADF-bound nitrogen were particularly high in Calliandra calothyrsus, Acacia polyacantha, Sesbania sesban, Acacia venosa and Acacia hockii. High levels of tannins were observed in Acacia species especially A. dolichocephala, A. hockii, A. microbotrya and A. salicina. High levels were also observed in Flemingia macrophyla and Leucaena pallida. The browse species differed (P 〈 0.05) in DM in sacco degradability coefficients. High potential degradability (PD) and effective degradability (ED) were observed in Sesbania spp, Moringa stenopetala, Indigofera arrecta, Chamaecytisus palmensis and Atriplex spp. The browses differed (P 〈 0.05) in asymptotic gas (Ag) production (ml g-1 OM), but had similar (P 〉 0.05) times of incubation at which half of the asymptotic gas had been formed. Preference and DM intake were positively correlated (P 〈 0.01) to NDFN, but negatively correlated (P 〈 0.05) to NDF and ADF. The PD and Ag were negatively (P 〈 0.001) related to NDF, ADF and lignin. Total phenols (TP) and condensed tannins (CT) were negatively (P 〈 0.05) related to PD, ED and Ag. A positive correlation was observed between CT and NDF-bound condensed tannins (r = 0.55, P 〈 0.001) and, CT and TP (r = 0.40, P 〈 0.01). Prediction equations were poor for DM intake and preference, moderate for gas production and good for potential and effective degradabilities. The phenolic components were more related to dry matter degradation and gas production than to preference and dry matter intake. NDFN and Ag made a positive contribution to both preference and DM intake. It was concluded that chemical constitutes such as N, NDF, NDFN, ADF and lignin are essential to predict the nutritive value of browses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005913119236
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Influence of Canopy Height and Fertilization Levels on the Resistance of Lycopersicon Hirsutum to Aculops Lycopersici (Acari: Eriophyidae) (1999)
    Springer
    Experimental and applied acarology 23 (1999), S. 633-642 
    Details
    ISSN: 1572-9702
    Keywords: tomato plants ; susceptibility ; mite ; tridecan-2-one ; nitrogen ; potasium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The objective of this work was to study the effect of NK fertilization levels and canopy height on the resistance of Lycopersicon hirsutum and Lycopersicon esculentum to Aculops lycopersici (Acari: Eriophydae). The effects of NK fertilization levels and canopy height in the leaf size and density of trichomes and their effects on tridecan-2-one (2-TD) and undecan-2-one (2-UD) limiting the attack of A. lycopersici on tomato plants were assessed. Different NK fertilization levels had no effect on the resistance of L. hirsutum to A. lycopersici. No significant differences were found in attack rates of this mite on leaves of the top and median parts of L. hirsutum canopy. The type and density of trichomes were the main determining factor of A. lycopersici attack on tomato plants. High trichome densities and type VI glandular trichomes which produce tridecan-2-one are important resistance factors on tomato plants. L. hirsutum showed a high resistance level to A. lycopersici due to high densities of type VI glandular trichomes and consequently higher levels of tridecan-2-one in its leaves.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006201915292
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Landscape-level interactions between topoedaphic features and nitrogen limitation in tallgrass prairie (1995)
    Springer
    Landscape ecology 10 (1995), S. 337-348 
    Details
    ISSN: 1572-9761
    Keywords: fire ; nitrogen ; NDVI ; transect ; watershed
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transects across watersheds with varying fire histories and remotely-sensed data were used to study vegetation-resource interactions in a tallgrass prairie in Kansas. Paired plots (fertilized, control) were established along these transects and sampled for grass and forb biomass during the 1989 and 1990 growing seasons. Fertilization resulted in significant production responses in grass and total biomass on the west slopes of the annually burned (ID) and infrequently burned (N4) watersheds for both years (p = 0.05). In 1989, fertilization also produced a significant increase in grass biomass on the west slope of the unburned transect (p = 0.05), however, total production was not significantly increased. East slopes were insensitive to nitrogen additions. Differences in production response along these transects were assessed by testing the interaction between fertilization response and slope position. Significant interactions occurred on both 1D and N4, but only in 1990. Production data for both years were also compared to Normalized Difference Vegetation Index (NDVI) values derived from thematic mapper (TM) images for 1989 and 1990. When differences among transects or watersheds were statistically different, a positive relationship between NDVI and biomass was observed. NDVI values accurately reflected the spatial patterns of production along these transects for both years although not necessarily the magnitude.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00130211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Estimating regional forest productivity and water yield using an ecosystem model linked to a GIS (1998)
    Springer
    Landscape ecology 13 (1998), S. 323-334 
    Details
    ISSN: 1572-9761
    Keywords: forest productivity ; NPP ; runoff ; climate ; nitrogen ; northeastern U.S. ; modeling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We used the PnET-II model of forest carbon and water balances to estimate regional forest productivity and runoff for the northeastern United States. The model was run at 30 arc sec resolution (approximately 1 km) in conjunction with a Geographic Information System that contained monthly climate data and a satellite-derived land cover map. Predicted net primary production (NPP) ranged from 700 to 1450 g m2 yr1 with a regional mean of 1084 g m2 yr1. Validation at a number of locations within the region showed close agreement between predicted and observed values. Disagreement at two sites was proportional to differences between measured foliar N concentrations and values used in the model. Predicted runoff ranged from 24 to 150 cm yr1with a regional mean of 63 cm yr1. Predictions agreed well with observed values from U.S. Geologic Survey watersheds across the region although there was a slight bias towards overprediction at high elevations and underprediction at lower elevations. Spatial patterns in NPP followed patterns of precipitation and growing degree days, depending on the degree of predicted water versus energy limitation within each forest type. Randomized sensitivity analyses indicated that NPP within hardwood and pine forests was limited by variables controlling water availability (precipitation and soil water holding capacity) to a greater extent than foliar nitrogen, suggesting greater limitations by water than nitrogen for these forest types. In contrast, spruce-fir NPP was not sensitive to water availability and was highly sensitivity to foliar N, indicating greater limitation by available nitrogen. Although more work is needed to fully understand the relative importance of water versus nitrogen limitation in northeastern forests, these results suggests that spatial patterns of NPP for hardwoods and pines can be largely captured using currently available data sets, while substantial uncertainties exist for spruce-fir.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008004423783
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Effect of landscape position on the sediment chemistry of abandoned-channel wetlands (1996)
    Springer
    Landscape ecology 11 (1996), S. 27-38 
    Details
    ISSN: 1572-9761
    Keywords: abandoned channels ; floodplain ; nitrogen ; organic matter ; phosphorous ; potassium ; sediment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The nature of sediments in abandoned channels is an important component of their development as floodplain wetlands. The texture, organic matter, phosphorous, potassium, and nitrogen content of sediments were determined for abandoned channels along the Iowa and Cedar Rivers near their confluence in Iowa. Differences in the levels of these constituents were examined among categories of three landscape gradients: present connectivity to the river, time since abandonment, and proximity to agricultural land use. Local scale processes of ecological development are seen in the importance of time for increased organic matter and nitrogen. Basin scale processes of sediment transport and deposition are revealed by the importance of connectivity for decreases in these two elements, and by the counter-intuitive findings for nitrogen and especially phosphorous and potassium in relation to agricultural proximity. Location on a floodplain is important for differentiating development, but it cannot be reduced to univariate gradients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02087111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    A GIS-based index for relating landscape characteristics to potential nitrogen leaching to wetlands (1996)
    Springer
    Landscape ecology 11 (1996), S. 237-255 
    Details
    ISSN: 1572-9761
    Keywords: wetlands ; non-point source pollution ; nitrogen ; watershed ; leaching ; geographic information system ; landscape ; groundwater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We developed a spatially-explicit, quantitative Nitrogen Leaching Index to assess the potential for non-point source subsurface nitrogen pollution to wetlands. The index was based on the leaching potential of the watershed soils, the amount of nitrogen available for leaching, and the spatial position of nitrogen sources in the watershed. A raster or cell-based geographic information system (GIS) was used to estimate the necessary data inputs for calculating the index, such as soil hydrologic group, land use/soil type combination, groundwater residence time, and location of septic systems. The Total and Average Watershed Nitrogen Leaching Index (TWNLI and AWNLI) were calculated by summing and averaging, respectively, individual cell contributions over a watershed. Analysis of nine wetland watersheds in central New York state, USA, with mixed forest and agricultural land uses illustrated the use of the index for identifying and ranking wetlands with potential nitrogen pollution. Results showed that the spatial characteristics of a watershed potentially can effect subsurface nitrogen delivery to groundwater-dominated wetlands. The use of an index based on watershed soils, topography, and land use may be useful for assessing potential nitrogen pollution to wetlands at a regional scale.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02071814
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Age-related changes in gene expression in the rat brain revealed by differential display (1996)
    Springer
    Cellular and molecular life sciences 52 (1996), S. 888-891 
    Details
    ISSN: 1420-9071
    Keywords: Ageing ; rat ; brain ; gene expression ; differential display
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We have used the polymerase chain reaction (PCR)-based technique of differential display to analyse changes in gene expression during ageing of the rat brain. In this approach we have compared three young adult (6 months) with three old adult (20 months) animals. RNA preparations from the homogenised brains were subjected to reverse transcriptase (RT)-PCR using 36 different combinations of primer pairs. Any PCR product which was consistently found to be more prominent in the three young brains compared to the three old brains, and vice versa, was scored as potentially representing a gene which was differentially expressed during the ageing of this tissue. Out of a possible 2000+PCR products we identified 44 that might represent genes that exhibit differential expression during ageing of the rat brain. An initial screen of these fragments, by Southern-blotting the PCR products and hybridising them with cDNA probes derived from either young or old brain RNA preparations, indicated that 40% of them represented genes that were differentially expressed. This approach is likely to prove invaluable for identifying cohorts of genes that show differential expression during the ageing process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01938876
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Stability and expression of amplified EPSPS genes in glyphosate resistant tobacco cells and plantlets (1996)
    Springer
    Plant cell reports 15 (1996), S. 431-436 
    Details
    ISSN: 1432-203X
    Keywords: glyphosate ; gene expression ; gene amplification ; cell culture ; resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The stability and expression of amplified 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) genes was examined in glyphosate resistant tobacco cells grown in glyphosate-free medium, and in plantlets regenerated from resistant cells. Amplified DNA was maintained in resistant cells grown in the absence of glyphosate for three years. Amplified EPSPS genes were retained in regenerated plantlets at levels comparable to those observed in the resistant cells, and EPSPS mRNA was overexpressed (compared to unselected plantlets). However, glyphosate resistance in cell lines grown in glyphosate-free medium declined 7-fold, and in regenerated plantlets approximately 20-fold, compared to resistant cells maintained under glyphosate selection. In plantlets, reduced resistance correlated with lower levels of EPSPS mRNA. Plantlets regenerated from resistant cells exhibited morphological variation, and had an approximate doubling of their nuclear genome size.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00232070
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Thermogravimetric Analysis of Vanadium Phosphorus Oxide Catalysts Doped with Cobalt and Iron (1998)
    Springer
    Journal of thermal analysis and calorimetry 53 (1998), S. 111-121 
    Details
    ISSN: 1572-8943
    Keywords: air ; cobalt dopant ; iron dopant ; n-butane ; nitrogen ; thermogravimetric analysis ; vanadium phosphorus oxides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The transformation of VOHPO4·0.5H2O (VPO) precursor doped with cobalt or iron for n-butane oxidation to maleic anhydride was investigated by thermogravimetric analysis under air and nitrogen, with and without n-butane in the flow. While almost no effect was observed in nitrogen or air, a strong influence of the doping was observed when n-butane was added to the nitrogen or air. This resulted in a delay of the decomposition of the precursor and a further reoxidation of the VPO catalyst, particularly for doping with cobalt at low percentage (1%). This shows that doping can change the oxidation state of vanadium phosphorus oxide catalysts, which can explain differences in their catalytic performances and the favourable effect of doping by cobalt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1010162018622
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Transport coefficients of air, argon-air, nitrogen-air, and oxygen-air plasmas (1995)
    Springer
    Plasma chemistry and plasma processing 15 (1995), S. 279-307 
    Details
    ISSN: 1572-8986
    Keywords: Transport coefficients ; transport properties ; viscosity ; thermal conductivity ; electrical conductivity ; diffusion coefficient ; Chapman-Etskog method ; air ; argon ; nitrogen ; oxygen ; plasma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract Calculated values of the viscosity, thermal conductivity and electrical conductivity of air and mixtures of air and argon, air and nitrogen, and air and oxygen at high temperatures are presented. In addition, combined ordinary, pressure, and thermal diffusion coefficients are given for the gas mixtures. The calculations, which assione local thermodynamic equilibrium, are performed for atmospheric pressure plasmas in the temperature range from 300 to 30,000 K. The results for air plasmas are compared with those of published theoretical and experimental studies. Significant discrepancies are found with the other theoretical studies; these are attributed to differences in the collision integrals used in calculating the transport coefficients. A number of the collision integrals used here are significantly more accurate than values used previously, resulting in more reliable values of the transport coefficients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01459700
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    The behavior of titanium, stainless steel, and copper-nickel alloys as plasma torch cathodes (1996)
    Springer
    Plasma chemistry and plasma processing 16 (1996), S. 577-603 
    Details
    ISSN: 1572-8986
    Keywords: Cathode erosion ; electrode materials ; argon ; nitrogen ; hydrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract Cathode erosion continues to be a problem hindering the widespread application of plasma technology. In this work, cathode erosion was studied on titanium, stainless steel 314, copper-nickel 10% and 30%, and copper 122 for magnetically rotated arcs operating in argon, nitrogen, and argon/hydrogen mixtures at a constant magnetic flux density of 0.1 T Titanium and stainless steel gave very low erosion rates in argon (0.2 and 0.3, μg/C respectively). Cupronickels were shown to be suitable for nitrogen and hydrogen plasmas. The slope of hydrogen solubility versus temperature in the cathode material was found to be important in determining hydrogen plasma erosion characteristics. When the plasma gas has a high solubility in the cathode material, or can react with the cathode, a negative erosion rate may result. When gas solubility in the cathode is low, oxide stability and mode of electron emission may govern the erosion rate. A high gas solubility in the cathode material, as with hydrogen, can result in mechanical erosion due to micro-explosions near the cathode surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01447010
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Soil chemistry change in a lowland english deciduous Woodland 1974–1991 (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 677-682 
    Details
    ISSN: 1573-2932
    Keywords: soils ; acidification ; ancient woodland ; nitrogen ; environmental change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract This study outlines the results of analysis of soil samples collected from fixed quadrats located in a regular pattern across Wytham Wood. Oxfordshire, England. The site contains plots of mixed deciduous ancient woodland and more recent plantations. A previous soil study was undertaken in 1974 and samples archived. Soils were resampled in 1991 and some re-analysis of the 1974 samples was undertaken. Soils were of a wide range in types from sands to gravels with a pH range of 3.0–7.0. Results showed some decline in pH in lower horizons, but most striking was a large increase in soil nitrogen for all horizons and soil types.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00476907
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Deposition gradients and foliar and soil leachate concentrations of air pollutants in Scots pine stands of S.-E. Finland and the Karelian Isthmus, N.-W. Russia (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 1263-1268 
    Details
    ISSN: 1573-2932
    Keywords: air pollution ; sulphur ; nitrogen ; base cations ; throughfall ; Scots pine ; needle elements ; soil leachate ; N.-W. Russia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Bulk precipitation and throughfall analyses in 50–100-year-old Scots pine stands revealed decreasing sulphur, nitrogen, calcium and magnesium deposition gradients, which extend from the St. Petersburg-Leningrad region and N.-E. Estonia to S.-E. Finland. The Ca and Mg deposition alleviate the acidifying effect of sulphur and nitrogen. The Scots pine canopies acted as a sink for ammonium and nitrate, while the canopy interactions increased sulphur, calcium and magnesium content in throughfall. Foliar S, N and Ca concentrations correlated positively with the corresponding deposition loads. In contrast, low foliar magnesium concentrations were detected in the vicinity of St. Petersburg. The results indicate that the sulphur and calcium deposition may have increased soil leachate S and Ca concentrations in the most polluted Scots pine stands.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00477155
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Expression of mRNA for vasoactive intestinal peptide in normal human colon and during inflammation (1995)
    Springer
    Molecular and cellular biochemistry 142 (1995), S. 1-7 
    Details
    ISSN: 1573-4919
    Keywords: vasoactive intestinal peptide ; ulcerative colitis ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The availability of colon provides a ready source of human neurons. Among the products of nerve cell bodies, vasoactive intestinal peptide is a neuropeptide that serves as a marker of non-adrenergic, non-cholinergic inhibitory nerves in colon. These nerves have been proposed to be involved in regulation of immune function, secretion, and smooth muscle function. In previous work, we identified decreased tissue levels of vasoactive intestinal peptide in a disorder of chronic colonic mucosal inflammation, ulcerative colitis. We hypothesized that diminished gene expression of vasoactive intestinal peptide could result in decreased tissue levels of this neuropeptide. Sigmoid colon was obtained at surgery from controls (n=6) and patients with ulcerative colitis (n=6). Vasoactive intestinal peptide mRNA was quantified by Northern blot hybridization and tissue levels of vasoactive intestinal peptide were determined by radioimmunoassay. Tissue vasoactive intestinal peptide was decreased only in the mucosalsubmucosal layer of ulcerative colitis (p=.02). There was a single 1.7 kbase vasoactive intestinal peptide transcript identified in both control colon and ulcerative colitis. Normalized vasoactive intestinal peptide mRNA levels were increased by 260% in ulcerative colitis compared to controls (p〈.01). These observations suggest that decreased vasoactive intestinal peptide gene expression or abnormal post-transcriptional processing are not primary defects in this disorder of chronic inflammation. The findings support the alternative hypothesis that axonal degeneration in ulcerative colitis could result in increased expression of neuronal vasoactive intestinal peptide mRNA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00928907
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Expression of hepatic calcium-binding protein regucalcin mRNA is elevated by refeeding of fasted rats: Involvement of glucose, insulin and calcium as stimulating factors (1995)
    Springer
    Molecular and cellular biochemistry 142 (1995), S. 35-41 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; insulin ; calcium ; gene expression ; rat liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The effect of refeeding on the expression of Ca2+-binding protein regucalcin mRNA in the liver of fasted rats was investigated. When rats were fasted overnight, the hepatic regucalcin mRNA level was reduced about 70% of that in feeding rats. Refeeding produced a remarkable elevation of hepatic regucalcin mRNA level (about 150–170% of fasted rats). Liver regucalcin concentration was appreciably increased by refeeding, although it was not altered by fasting. The oral administration of glucose (2 g/kg body weight) to fasted rats caused a significant increase in hepatic regucalcin mRNA level. Moreover, hepatic regucalcin mRNA level was clearly elevated by a single subcutaneous administration of insulin (10 and 100 U/kg) to fasted rats. The hormonal effect was not further enhanced by the simultaneous administration of calcium chloride (250 mg Ca/kg) to fasted rats, although calcium administration stimulated regucalcin mRNA expression in the liver. The present study suggests that the expression of hepatic regucalcin mRNA stimulated by refeeding is significantly involved in the action of insulin and/or calcium as stimulating factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00928911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Specific species and tissue differences for the gene expression of calcium-binding protein regucalcin (1995)
    Springer
    Molecular and cellular biochemistry 143 (1995), S. 67-71 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; gene distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The existence and expression of gene encoding the Ca2+-binding protein regucalcin in various species and tissues were investigated with Southern and Northern hybridization analyses using regucalcin cDNA (0.9 kb of open reading frame). Genomic Southern hybridization analysis demonstrated that regucalcin gene was widely conserved among higher animals including human, monkey, rat, mouse, dog, bovine, rabbit and chicken. The gene was not found in yeast. The Northern blot analysis of poly (A)+RNAs extracted from the liver of various species showed that regucalcin mRNA was predominantly expressed in rat and mouse, although the expression was also seen in human, bovine and chicken. Furthermore, the enzyme-linked immunoadsorbent assay (ELISA) with rabbit-anti-regucalcin IgG indicated that hepatic regucalcin concentration was most pronounced in rat as compared with that of guinea pig, mouse and chicken. These observations show that the gene expression of regucalcin and its protein synthesis is unique in the liver of rats, suggesting the existence of a specific mechanism in demonstrating regucalcin synthesis from gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00925928
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    17β-Estradiol stimulates the expression of hepatic calcium-binding protein regucalcin mRNA in rats (1995)
    Springer
    Molecular and cellular biochemistry 143 (1995), S. 137-141 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; estrogen ; gene expression ; rat liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The effect of nuclear receptor-related hormones on the expression of hepatic calcium-binding protein regucalcin mRNA in rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin cDNA (0.9 kb of open-reading frame). A single subcutaneons administration of 17β-estradiol (0.5, 1.0 and 2.0 mg/kg body weight) in rats induced a remarkable increase of regucalcin mRNA in liver; the level was about 200% of control at 24 h after the administration of 2.0 mg/kg. The increase showed about 350% even at 6 h after the administration. Meanwhile, hepatic regucalcin mRNA level was not appreciably altered by a single subcutaneous administration of thyroxine (T4) (20, 40 and 80 mg/kg) or hydrocortisone (10 and 30 mg/kg) in rats. The present study demonstrates that the expression of hepatic regucalcin mRNA is stimulated by estrogen action in the liver nuclei of rats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01816947
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Thyroid hormone inhibits fatty acid synthase gene transcription in chicken liver (1995)
    Springer
    Molecular and cellular biochemistry 144 (1995), S. 105-108 
    Details
    ISSN: 1573-4919
    Keywords: fatty acid synthase ; gene expression ; and thyroid hormone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The effect of triiodothyronine (T3) on regulation of fatty acid synthase in chicken liver was investigated. In hypothyroid animals, enzyme activity was about one half of that in euthyroid animals. T3 treatment increased the enzyme activity in hypothyroid animals. There is little difference in both the mRNA concentration and the transcription rate between euthyroid and hypothyroid animals. T3 treatment markedly decreased both the mRNA concentration and the transcription rate in euthyroid and hypothyroid animals. These results suggested that T3 maintained the normal level of enzyme expression primarily by stimulating the post-transcriptional step, while the transcription of the gene was inhibited by hyperthyroidism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00944388
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin mRNA in hepatoma cells (1996)
    Springer
    Molecular and cellular biochemistry 155 (1996), S. 85-90 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; rat hepatoma ; Morris hepatoma cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Whether the gene expression of hepatic Ca2+-binding protein regucalcin is altered in hepatomas was investigated. The change in regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin complementary DNA (0.9 kb). Rat hepatoma was induced by continuous feeding of basal diet containing 0.06% 3′-methyl-4-dimethylaminoazobenzene (3′-Me-DAB). After 35 weeks feeding, rats were sacrificed, and the non-tumorous and tumorous tissues of the livers were removed. In individual rats, the regucalcin mRNA levels in the tumorous tissues were generally decreased in comparison with that of the non-tumorous tissues of the chemical-fed rats, although the chemical administration might decrease the mRNA expression in normal rat liver, suggesting that the chemical administration causes a suppresive effect on the mRNA expression. When the genomic DNA extracted from the liver tumorous tissues was digested with restriction enzymes (EcoRI, BamHI and HindIII) and analyzed by Southern blotting, no rear-ranged band was found in the regucalcin gene from the hepatoma. Interestingly, in the transplantable Morris hepatoma cells, the regucalcin mRNA was markedly expressed, while the albumin mRNA was expressed only slightly. The present study demonstrates that regucalcin mRNA is clearly expressed in the transformed cells (Morris hepatoma cells).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00714337
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Steroid hormonal regulation of calcium-binding protein regucalcin mRNA expression in the kidney cortex of rats (1996)
    Springer
    Molecular and cellular biochemistry 155 (1996), S. 105-111 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; aldosterone ; estrogen ; dexamethasone ; gene expression ; rat kidney cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The effect of various steroid hormones on the expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using rat liver regucalcin complementary DNA (0.9 kb of open-reading frame). Regucalcin mRNA was expressed in the kidney cortex but not the medulla. Rats received a single subcutaneous administration of steroid; the animals were sacrificed 60 min after the treatment of aldosterone (2.5, 5.0 and 10 μg/100 g body weight) or 6 h after the treatment of estrogen (17β-estradiol; 0.05, 0.1 and 0.2 mg/100 g), hydrocortisone (0.5, 1.0 and 3.0 mg/100 g) and dexamethasone (50, 100 and 150 μg/100 g). Regucalcin mRNA levels in the kidney cortex were clearly diminished by the administration of aldosterone or estrogen, while hydrocortisone administration had no effect. The administration of dexamethasone (100 μg/100 g) caused a remarkable increase of regucalcin mRNA levels in the kidney cortex. The dexamethasone-induced increase in regucalcin mRNA levels was completely blocked by the simultaneous administration of cycloheximide (150 μg/100 g), although the drug administration had no effect on the mRNA levels in control rats. Meanwhile, the dexamethasone administration did not cause an appreciable alteration of calcium content in the kidney cortex. The present study demonstrates that, of the various steroid hormones used, dexamethasone uniquely has a stimulatory effect on regucalcin mRNA expression in the kidney cortex of rats. The steroid effect may be mediated through a newly synthesized protein.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Estrogen effects in the heart (1996)
    Springer
    Molecular and cellular biochemistry 160-161 (1996), S. 307-313 
    Details
    ISSN: 1573-4919
    Keywords: myocardium ; hypertension ; gene expression ; estrogens ; cardiac hypertrophy ; signal transduction ; genetic program
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Gender specific differences in cardiovascular disease are largely mediated by sex hormones. The use of estrogens significantly reduces the overall incidence of heart disease in postmenopausal women. Beneficial effects of estrogens on plasma lipoprotein levels are clearly established. However, these do not explain the magnitude of risk reduction seen in clinical studies. Thus, additional and currently unknown functions of estrogens must be operative. Elucidation of the exact estrogen action in the heart will have important implications in the treatment of cardiovascular disease. It will probably enhance the therapeutic repertoire in treating heart disease, the most common cause of death in industrialized countries. We will review the current understanding of the function of estrogens in the heart and discuss potential strategies on how to apply these data to clinical practice.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00240064
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Calcium-binding protein regucalcin mRNA expression in the kidney cortex is suppressed by saline ingestion in rats (1996)
    Springer
    Molecular and cellular biochemistry 162 (1996), S. 139-144 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; saline ingestion ; hypertensive rats ; kidney cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The effect of adrenalectomy (ADX) or saline ingestion, which is a hypertensive factor, on the expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using rat liver regucalcin complementary DNA (0.9 kb of open-reading frame). Regucalcin mRNA was expressed in the kidney cortex but not the medulla. Rats were adrenalectomized, and 48 h later they were sacrificed. ADX caused a reduction of regucalcin mRNA levels in the kidney cortex, suggesting that adrenal glands participate in the regulation of the mRNA expression. This reduction was not restored by the subcutaneous administration of dexamethasone with an effective dose (1 mg/kg body weight), which can stimulate kidney regucalcin mRNA expression. Regucalcin mRNA levels in the kidney cortex of rats were markedly suppressed by the ingestion of saline for 7 days. The ADX-induced decrease of renal cortex regucalcin mRNA levels was not appreciably restored by saline ingestion. Moreover, regucalcin mRNA levels in the kidney cortex of spontaneous hypertensive rats (SHR) were clearly decreased as compared with that of control (Wistar-Kyoto) rats. Meanwhile, calcium content in the kidney cortex was not significantly decreased by ADX or saline ingestion. The present study suggests that the expression of regucalcin mRNA in the kidney cortex of rats is suppressed by saline administration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00227541
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Calreticulin inhibits glucocorticoid– but not cAMP–sensitive expression of tyrosine aminotransferase gene in cultured McA–RH7777 hepatocytes (1997)
    Springer
    Molecular and cellular biochemistry 171 (1997), S. 37-43 
    Details
    ISSN: 1573-4919
    Keywords: calreticulin ; gene expression ; steroid receptor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Calreticulin is a ubiquitously expressed Ca2+ binding protein of the endoplasmic reticulum which inhibits DNA binding and transcriptional activation by steroid hormone receptors. In this study the effects of calreticulin on tyrosine aminotransferase (TAT) gene expression in cultured McA–RH7777 hepatocytes was investigated. McA–RH7777 cells were stably transfected with calreticulin expression vector to generate cells overexpressing the protein. The transcriptional activity of the TAT gene, which is glucocorticoid–sensitive and cAMP–dependent, was investigated in the mock transfected McA–RH7777 and in cells overexpressing calreticulin (designated McA–11 and McA–17). In the presence of dexamethasone or the cAMP analog (CTP–cAMP) expression of the TAT gene was induced in mock transfected McA–RH7777 cells by approximately 4.5 and 5 fold, respectively. In McA–11 and McA–17 cells, overexpressing calreticulin, glucocorticoi ever, the CTP–cAMP–dependent expression of the TAT gene was not affected. The ability of calreticulin to inhibit glucocorticoid–sensitive TAT gene expression but not the cAMP–dependent expression of the gene suggests that the protein affects specifically the action of transcription pathways involving steroid receptors or transcription factors containing KxFF(K/R)R–like motifs. Calreticulin may play an important role in the regulation of glucocorticoid–sensitive pathway of expression of the hepatocytes specific genes during development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006865108833
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Thiol modulation of TNFα and IL-1 induced MnSOD gene expression and activation of NF-κB (1995)
    Springer
    Molecular and cellular biochemistry 148 (1995), S. 45-57 
    Details
    ISSN: 1573-4919
    Keywords: manganese ; superoxide dismutase ; gene expression ; hyperoxide lung injury ; nuclear factor kappa B
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract TNFα and IL-1 each can activate NF-κB and induce gene expression of manganese superoxide dismutase (MnSOD), a mitochondrial matrix enzyme which can provide critical protection against hyperoxic lung injury. The regulation of MnSOD gene expression is not well understood. Since redox status can modulate NF-κB and potential κB site(s) exist in the MnSOD promoter, the effect of thiols (including NAC, DTT and 2-ME) on TNFα and IL-1 induced activation of NF-κB and MnSOD gene expression was investigated. Activation of NF-kB and increased MnSOD expression were potentiated by thiol reducing agents. In contrast, thiol oxidizing or alkylating agents inhibited both NF-κB activation and elevated MnSOD expression in response to TNFα or IL-1. Since protease inhibitors TPCK and TLCK can inhibit NF-κB activation, we also investigated the effect of these compounds on MnSOD expression and NF-κB activation. TPCK and TLCK each inhibited MnSOD gene expression and NF-κB activation. Since the MnSOD promoter also contains anAP-1 binding site, the effect of thiols and thiol modifying agents on AP-1 activation was investigated. Thiols had no consistent effect onAP-1 activation. Likewise, some of the thiol modifying compounds inhibited AP-1 activation by TNFα or IL-1, whereas others did not. Since diverse agents had similar effects on activation of NF-κB and MnSOD gene expression, we have demonstrated that activation of NF-κB and MnSOD gene expression are closely associated and that reduced sulfhydryl groups are required for cytokine mediation of both processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00929502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Stimulatory effect of calcium administration on regucalcin mRNA expression is attenuated in the kidney cortex of rats ingested with saline (1998)
    Springer
    Molecular and cellular biochemistry 178 (1998), S. 275-281 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; calmodulin ; spontaneous hypertensive rats ; rat kidney cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats ingested with saline was investigated. The alteration in regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin complementary DNA (0.9 kb of open reading frame). Rats were freely given saline as drinking water for 7 days. Regucalcin mRNA levels in the kidney cortex were suppressed by saline ingestion. When calcium chloride (10 mg Ca/100 g body weight) was intraperitoneally administered to rats ingested with saline for 7 days, the effect of calcium administration to increase regucalcin mRNA levels was weakened by saline ingestion. Such effect was also seen by the administration of 2.5 and 5 mg Ca/100 g. Regucalcin mRNA levels in the kidney cortex of spontaneous hypertensive rats (SHR) were not appreciably increased by the administration of calcium (10 mg/100 g). Meanwhile, calcium content in the kidney cortex was significantly elevated by the administration of calcium (10 mg/100 g) to normal rats. This increase was weakened in saline-ingested rats. Moreover, Ca2+/calmodulin-dependent protein kinase activity in the cytosol of kidney cortex was significantly decreased by saline ingestion. These results suggest the possibility that saline ingestion-induced suppression of regucalcin mRNA expression in the kidney cortex is partly involved in the attenuation of Ca2+ signalling.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006898910955
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Increased peroxisomal fatty acid β-oxidation and enhanced expression of peroxisome proliferator-activated receptor-α in diabetic rat liver (1999)
    Springer
    Molecular and cellular biochemistry 194 (1999), S. 227-234 
    Details
    ISSN: 1573-4919
    Keywords: microbodies ; diabetes mellitus ; steroid hormone receptor ; β-oxidation ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract To determine whether the increased fatty acid β-oxidation in the peroxisomes of diabetic rat liver is mediated by a common peroxisome proliferation mechanism, we measured the activation of long-chain (LC) and very long chain (VLC) fatty acids catalyzed by palmitoyl CoA ligase (PAL) and lignoceryl CoA ligase and oxidation of LC (palmitic acid) and VLC (lignoceric acid) fatty acids by isotopic methods. Immunoblot analysis of acyl-CoA oxidase (ACO), and Northern blot analysis of peroxisome proliferator-activated receptor (PPAR-α), ACO, and PAL were also performed. The PAL activity increased in peroxisomes and mitochondria from the liver of diabetic rats by 2.6-fold and 2.1-fold, respectively. The lignoceroyl-CoA ligase activity increased by 2.6-fold in diabetic peroxisomes. Palmitic acid oxidation increased in the diabetic peroxisomes and mitochondria by 2.5-fold and 2.7-fold, respectively, while lignoceric acid oxidation increased by 2.0-fold in the peroxisomes. Immunoreactive ACO protein increased by 2-fold in the diabetic group. The mRNA levels for PPAR-α, ACO and PAL increased 2.9-, 2.8- and 1.6-fold, respectively, in the diabetic group. These results suggest that the increased supply of fatty acids to liver in diabetic state stimulates the expression of PPAR-α and its target genes responsible for the metabolism of fatty acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006930513476
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Regulation of the apolipoprotein E by dietary lipids occurs by transcriptional and post-transcriptional mechanisms (1996)
    Springer
    Molecular and cellular biochemistry 155 (1996), S. 153-162 
    Details
    ISSN: 1573-4919
    Keywords: apolipoprotein B and E ; lipid ; gene expression ; rat ; mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The aim of the present investigation was to study the regulation of apolipoprotein E by two dietary nutrients, saturated fat and cholesterol, known to raise plasma cholesterol levels. ApoE is a protein component of several classes of lipoproteins including VLDL and HDL, and dietary lipids may regulate VLDL and apoE-containing HDL particles through their effects on apoE gene. Male rats and mice were fed the following 4 diets: control diet (C); high cholesterol diet with 0.5% cholesterol (HC); high fat diet with 20% hydrogenated coconut oil (HF); and high fat plus high cholesterol diet with 0.5% cholesterol and 20% fat (HF/C). Plasma cholesterol levels remained unchanged on HC diet, but in mice VLDL-cholesterol increased by 31%. HF diet increased VLDL and LDL by 15–17% in rats, and 21% in mice. A combination of fat and cholesterol diet showed pronounced effects on plasma lipoprotein concentrations, raising apoB-containing particles by 21% and 44% in mice and rats, respectively. Plasma apoE levels increased significantly on all diets. The mechanism of regulation of increased plasma apoB and apoE levels was examined. Quantification of hepatic apoB mRNA showed a lack of correlation between plasma apoB and hepatic apoB mRNA levels, suggesting that posttranscriptional regulation increased plasma apoB-containing lipoproteins in animals fed saturated fat diets. Hepatic apoE mRNA levels increased significantly in animals fed cholesterol-rich diets. However, despite increased plasma apoE levels on diet containing only saturated fat, hepatic apoE mRNA did not change. Synthesis of apoE on the liver polysomes increased selectively on cholesterol-rich diets. These results suggest that cholesterol-rich diets altered apoE, in part, by transcriptional mechanism, and saturated fat-rich diets increased plasma apoE levels by posttranscriptional mechanism, possibly decreased receptor-mediated uptake of apoE-containing particles. The regulation of LDL receptor was also studied since plasma apoB and E levels may be altered by LDL receptor-mediated uptake by the hepatocytes. As expected, high cholesterol diet decreased LDL receptor mRNA by 30–40%. However, the LDL receptor protein on liver membranes did not change on any of the test diets in both animal species. Hepatic cholesterol content increased several fold selectively on high cholesterol diets. These findings suggest that: 1) both transcriptional and posttranscriptional mechanisms are important in regulating plasma apoB and E containing lipoproteins; 2) dietary cholesterol regulates apoE gene by a transcriptional mechanism anddietary saturated fat by posttranscriptional mechanism; and 3) changes in the hepatic apoE and LDL receptor mRNA are associated with the changes in intracellular cholesterol concentrations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229312
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats: The stimulation by calcium administration (1995)
    Springer
    Molecular and cellular biochemistry 146 (1995), S. 71-77 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; rat kidney cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin complementary DNA (0.9 kb of open-reading frame). Regucalcin mRNA was expressed in the kidney cortex, and this expression was clearly increased by a single intraperitoneal administration of calcium chloride solution (5–15 mg Ca/100 g body weight) in rats; this increase was remarkable at 60–120 min after the administration. Thyroparathyroidectomy (TPTX) caused a slight decrease of regucalcin mRNA levels in the kidney cortex. However, the administration of calcium (10 mg/100 g) in TPTX rats produced a clear increase of regucalcin mRNA levels in the kidney cortex. The subcutaneous administration of calcitonin (10–100 MRC mU/100 g) or parathyroid hormone [1–34] (1–10 U/100 g) in TPTX rats which received calcium (10 mg/100 g) administration did not cause an appreciable alteration of regucalcin mRNA levels in the kidney cortex, suggesting that the mRNA expression is not stimulated by calcium-regulating hormones. The administration of trifluoperazine (TFP; 5 mg/100 g), an inhibitor of Ca2+/calmodulin action, completely blocked the expression of regucalcin mRNA stimulated by calcium administration. Now, calcium content in the kidney cortex was significantly elevated by a single intraperitpneal administration of calcium (10 mg/100 g) in rats. The present study clearly demonstrates that the expression of regucalcin mRNA in the kidney cortex is stimulated by calcium administration in rats. This expression may be mediated through Ca2+/calmodulin action in the kidney cortex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00926884
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Molecular cloning, sequencing and expression analysis of a fatty acid transport gene in rat heart induced by ischemic preconditiong and oxidative stress (1996)
    Springer
    Molecular and cellular biochemistry 160-161 (1996), S. 241-247 
    Details
    ISSN: 1573-4919
    Keywords: fatty acid transport protein ; gene expression ; subtractive hybridization ; oxidative stress ; ischemia/reperfusion ; ischemic preconditioning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract In this study, ischemia and oxidative stress-inducible gene expression in heart was examined by subtractive hybridization technique. Total RNA was isolated from ventricular muscle fragments of normal and oxidative stress-induced hearts. Poly (A)+ RNA was purified followed by the construction of a plasmid cDNA library. This was followed by the subtractive screening of oxidative stress-induced cDNA library. The positive colonies were amplified and the plasmid isolated. An aliquot was subjected to restriction cutting with Bam H1 and EcoRl; the fragments corresponding to cDNA insert were separated by electrophoresis, radiolabeled by random-primed DNA synthesis, and used as probes in standard Northern blotting experiments. An aliquot containing the plasmid from the confirmed positives was then subjected to bidirectional partial DNA sequencing (using M13 and T7/T3α primers) by the chain-extension/chain termination method. These sequences were subjected to a computerized search for homologies against all sequences in the updated worldwide Gen Bank and EMBL sequence databases followed by restriction mapping and reading frame identification. Out of 24 putative positive colonies screened, one clone was matched with 〉 97% homology with FAT gene that has been implicated in binding or transport of long chain fatty acids. cDNA probe synthesized from this clone identified two major transcripts of 4.8 and 2.9 kb. Additional experiments were then performed where isolated perfused rat hearts were subjected to the following treatments: (1) 5 min ischemia; (2) 10 min ischemia; (3) 20 min ischemia; (4) 5 min ischemia followed by 10 min reperfusion (ischemic preconditioning); and (5) 5 min ischemia followed by 10 min reperfusion, repeated four times (4 × preconditioning). RNAs were extracted from these hearts and hybridized with the FAT cDNA probe. The results indicated that FAT gene was induced by oxidative stress, ischemic preconditioning, but not by ischemia. (Mol Cell Biochem 160/161: 241–247, 1996)
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00240055
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Hepatic calcium-binding protein regucalcin concentration is decreased by streptozotocin-diabetic state and ethanol ingestion in rats (1997)
    Springer
    Molecular and cellular biochemistry 168 (1997), S. 67-72 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; diabetic state ; ethanol ; liver injury
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The alteration in calcium-binding protein regucalcin in the liver and serum of rats with streptozotocin (STZ)-diabetic state or ethanol ingestion was investigated. STZ (6.0 mg/100 g body weight) was subcutaneously administered in rats, and 1 or 3 weeks later they were sacrificed by bleeding. Liver regucalcin mRNA levels were not clearly altered by the diabetic state, as evidenced by Northern blotting using regucalcin cDNA (0.9 kb of open reading frame). Based on enzyme-linked immunoadsorbent assay (ELISA) with rabbit-anti-regucalcin IgG, hepatic regucalcin concentration was decreased about 50% of control levels by STZ treatment. However, serum regucalcin concentration was not significantly altered by STZ treatment. Meanwhile, when rats ingested ethanol (10 and 30%) in the drinking water for 2 weeks, liver regucalcin mRNA levels were clearly increased, although hepatic regucalcin concentration was significantly decreased. Serum regucalcin concentration was not appreciably altered. Serum transaminases (GOT and GPT) activities were significantly increased at 1 or 3 weeks after STZ administration in rats, while their activities were not altered by ethanol ingestion. The present study demonstrates that hepatic regucalcin concentration is decreased independent of mRNA expression in the STZ-diabetes and during ethanol ingestion in rats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006822606198
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Effect of angiotensin II on myocardial collagen gene expression (1996)
    Springer
    Molecular and cellular biochemistry 163-164 (1996), S. 231-237 
    Details
    ISSN: 1573-4919
    Keywords: extracellular matrix ; angiotensin II ; fibrillar collagen ; cardiac fibrosis ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Recent studies suggest that angiotensin II (angiotensin) may be involved in the regulation of metabolism of the cardiac extracellular matrix (ECM). Two major components of ECM are collagen types I and III which play an important role in maintaining the structure and function of the heart. Although the cellular metabolism of collagen is very complex (especially at the posttranslational level), we chose to address events that occur relatively early in the synthesis of cardiac collagen molecules. To gain an understanding of the role of angiotensin in the regulation of cardiac collagen gene expression, we studied the effect of three different doses of angiotensin (12, 24, and 48 μg/kg/h) on adult heart and cultured neonatal cardiac fibroblasts. The steady-state mRNA abundance of collagen types I and III was monitored using Northern blot analysis in both left and right ventricular samples at day 3 of angiotensin infusion and in cultured cardiac fibroblasts stimulated with angiotensin. In all mRNA abundance studies, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) signal was used to normalize the data for possible differences in loading and/or transfer of total RNA. Both collagen types I/GAPDH and III/GAPDH mRNA signal ratios were increased significantly in left ventricle in all dose regimens used for angiotensin infusion. Only the collagen type I/GAPDH mRNA signal ratio was increased in right ventricle with angiotensin infusion. Angiotensin (10−7-10−5 M) had no effect on the steady-state mRNA abundance of collagen genes in cultured neonatal cardiac fibroblasts after 24 h treatment in serum-free conditions. Our results confirm that infusion of angiotensin may upregulate steady-state collagen gene mRNA abundance in the heart. Angiotensin had no observable effect on collagen mRNA abundance in neonatal fibroblast culture. An explanation for the current results may be that angiotensin causes the release of undefined factors from cardiac myocytes, and that these secondary factors may be involved in either the activation of collagen gene transcription or in alteration of stability of collagen mRNA transcripts via a paracrine mechanism. Although our results indicate hemodynamic loading may potentiate the action of angiotensin, this scenario is unlikely as collagen type I gene expression was increased in the normotensive right ventricle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00408663
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Tamoxifen enhances interferon-regulated gene expression in breast cancer cells (1997)
    Springer
    Molecular and cellular biochemistry 167 (1997), S. 169-177 
    Details
    ISSN: 1573-4919
    Keywords: tamoxifen ; interferon ; gene expression ; breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The molecular basis for the enhanced growth inhibition of MCF-7 human breast cancer xenografts by a combination of human interferon-β (IFN-β) and tamoxifen was investigated. Treatment of MCF-7, MDA-MB-231, and BT-20 cells with the combination of IFN-β and tamoxifen resulted in enhanced antiproliferative effects in vitro. Treatment with the combination of IFN-β and tamoxifen enhanced the expression of several IFN-β-inducible genes in human breast carcinoma cell lines relative to levels induced by IFN-β alone. Tamoxifen alone did not induce transcription of IFN-stimulated genes (ISGs). Augmentation of ISG expression by the combination of IFN-β and tamoxifen was noted in breast tumor cell lines irrespective of their functional estrogen receptor (ER) status or their dependence on estradiol for growth, suggesting that upregulation of ISGs was independent of ER status. Enhancement of IFN-stimulated gene expression by tamoxifen occurred at the transcripti onal level. Expression of transfected reporter genes under the control of IFN-α/β regulated promoters was also enhanced in IFN-β and tamoxifen-treated cells. Similarly, transcriptional induction of chimeric reporter plasmids driven by an IFN-γ inducible promoter (GAS; IFN-γ activated site) was also enhanced by the combination of IFN-γ and tamoxifen. In tamoxifen treated cells, IFN-β and IFN-γ readily activated transcription factors ISGF-3 and GAF, respectively. Therefore, augmentation of ISG expression by tamoxifen is an early event in the antitumoral activity of this drug combination. (Mol Cell Biochem 167: 169-177, 1997)
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006854110122
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Use of a hammerhead ribozyme with cationic liposomes to reduce leukocyte type 12-lipoxygenase expression in vascular smooth muscle (1997)
    Springer
    Molecular and cellular biochemistry 172 (1997), S. 47-57 
    Details
    ISSN: 1573-4919
    Keywords: smooth muscle ; gene transfer ; DNA ; RNA ; ribozyme ; liposome ; lipoxygenase ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Chemically synthesized hammerhead-type ribozymes targeted against the porcine leukocyte-type 12-lipoxygenase (LO) have been developed and studied. One chimeric ribozyme consists of DNA in the non-enzymatic portions, and RNA in the enzymatic core as well as two phosphorothioate internucleotide linkages at 3′ terminus. The second ribozyme consists of ribonucleotide sequences generated by in vitro transcription. In this chapter we describe methodologies to first analyze the ribozyme catalytic activity in vitro by studying cleavage of target RNA in vitro. The subsequent sections will describe how to target the catalytic ribozyme and deliver it to porcine vascular smooth muscle cells (PVSMC) by a liposome-mediated method. Finally ways to evaluate its activity to inhibit expression of the 12-LO mRNA will be presented. These results demonstrate the feasibility of using ribozymes as novel candidates for therapeutic agents to block specific gene expression in vascular cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006855219018
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Construction of a human heart cDNA library and identification of cardiovascular based genes (CVBest) (1997)
    Springer
    Molecular and cellular biochemistry 172 (1997), S. 81-87 
    Details
    ISSN: 1573-4919
    Keywords: heart ; DNA ; library ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The availability of high quality cDNA libraries is often crucial to the successful identification and characterization of genes. The concepts and potential pitfalls of constructing cDNA libraries are presented. Various applications requiring high quality cDNA libraries are outlined, including large-scale single pass sequencing of cDNA clones to generate expressed sequence tags (ESTs) and differential screening of cDNA libraries. The usefulness of combining such approaches for the discovery of novel disease-related and cardiovascular-based ESTs (CVBest) is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006811403996
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Hydrogen peroxide-induced expression of the proto-oncogenes, c-jun, c-fos and c-myc in rabbit lens epithelial cells (1997)
    Springer
    Molecular and cellular biochemistry 173 (1997), S. 59-69 
    Details
    ISSN: 1573-4919
    Keywords: hydrogen peroxide ; oxidative stress ; gene expression ; lens epithelial cells ; N-acetylcysteine ; pyrrolidine dithiocarbamate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The involvement of H2O2 in cataract development has been established inboth human patients and animal models. At the molecular level H2O2 has beenobserved to cause damage to DNA, protein and lipid. To explore the oxidativestress response of the lens system at the gene expression level, we haveexamined the effects of H2O2 on the mRNA change of the proto-oncogenes,c-jun, c-fos and c-myc in a rabbit lens cell line, N/N1003A. H2O2 treatmentof the rabbit lens epithelial cells for 60 min induces quick up-regulationof both c-jun and c-fos mRNAs. The maximal induction is 38 fold for c-jun at150 µM and 72 fold for c-fos at 250 µM H2O2. Treatment ofN/N1003A cells with 50-250 µM H2O2 for 60 min leads to a 2-5 foldincrease of the c-myc mRNA level. H2O2 also induces an up-regulation intransactivity of the activating protein-1 (AP-1) as shown with a reportergene driven by a prolactin gene promoter with 4 copies of AP-1 binding sitesinserted in the upstream of the promoter. Maximal induction occurs with 150µM H2O2. In the same system, the antioxidants, N-acetyl-cysteine (NAC)and pyrrolidine dithiocarbamate (PDTC) at concentrations shown toup-regulate the mRNAs of both c-jun and c-fos, also enhance thetransactivity of AP-1. NAC and PDTC have different effects in modulating theinduction of AP-1 activity by H2O2 and TPA. These results reveal thatoxidative stress regulates expression of various regulatory genes in lenssystems, which likely affects cell proliferation, differentiation andviability and thus affect normal lens functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006828402225
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Molecular cloning of the cDNA coding for regucalcin and its mRNA expression in mouse liver: The expression is stimulated by calcium administration (1997)
    Springer
    Molecular and cellular biochemistry 173 (1997), S. 127-133 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; cDNA cloning ; gene expression ; mouse liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The molecular cloning of the cDNA coding for a Ca2+-binding proteinregucalcin and its mRNA expression in mouse liver were investigated. ThecDNA clone encoding a regucalcin was isolated from a mouse liver cDNAlibrary and sequenced. Analysis of the sequence of the cloned cDNA showedthat the cDNA encoded the complete amino acid sequence of the mouseregucalcin molecule; the cDNA had an open reading frame of 897 bp. Mouseregucalcin was composed of 299 amino acid residues, and its molecular weightwas estimated to be 33,406 Da. The amino acid sequence of mouse regucalcinhad 94% homology, as compared with that of rat regucalcin. Northernblot analysis with the mouse liver cDNA probe revealed that mouse regucalcinmRNA was mainly present in the liver but only slightly in the kidney with asize of 1.8 kb. Hepatic regucalcin mRNA level of male mouse was higher thanthat of female mouse. A single intraperitoneal administration of calciumchloride (5, 15, and 30 mg Ca2+/100 g body weight) to mice induced aremarkable increase in regucalcin mRNA in the liver; the increase inregucalcin mRNA levels at 30 min after calcium administration wasdose-dependent. The present results demonstrate that regucalcin mRNA in miceis uniquely expressed in the liver, and that its expression is stimulated bycalcium administration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006887929369
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Cardiac hypertrophy: Old concepts, new perspectives (1997)
    Springer
    Molecular and cellular biochemistry 176 (1997), S. 273-279 
    Details
    ISSN: 1573-4919
    Keywords: cardiac hypertrophy ; myosin heavy chain ; gene expression ; adrenergic system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Growth of the heart in hypertrophy is accompanied by changes in the phenotypic expression of cardiac genes. To explore the molecular basis of cardiac hypertrophy, we have analyzed the regulation of myosin heavy chain gene (MHC) expression. In one set of experiments, pressure overload on the rat heart was produced by constriction of the abdominal aorta. Changes in the α and β-MHC mRNA were then studied in overloaded hearts and following load removal. Pressure overload resulted in down-regulation of the α-MHC with corresponding up-regulation of the steady state level of β-MHC mRNA. Load removal (debanding) resulted in regression of cardiac hypertrophy and a rapid return of α-MHC mRNA to normal values. In contrast, the recovery in β-MHC mRNA was much slower to the extent that it remained substantially elevated compared to respective sham controls even after 7 weeks of post-debanding. These results suggest that putative load-related signals independently regulate two genes. Several lines of evidence indicate that adrenergic nervous system plays an important role in the induction and maintenance of cardiac hypertrophy and in the redistribution of myosin isoforms. We have analyzed the effect of cAMP inducing agents on the regulation of a-MHC gene in primary cultures of the fetal (18 day) rat cardiac myocyte. Inclusion of 8 Br-cAMP in the culture media increased the expression of α-MHC promoter/reporter construct comprising of 2.9 kb upstream sequence of the α-MHC gene. Several deletion mutations in the α- MHC gene promoter defined the cAMP responsive boundaries to be a 32 bp region comprising of -71 to -40 bp sequences. Deletion of this region resulted in loss of cAMP response as well as in basal expression of α-MHC promoter/reporter construct. These data suggest a role of β-adrenergic pathway in the modulation of α-MHC gene expression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006865515646
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin mRNA in the cloned rat hepatoma cells (Hr-II-E) is stimulated through Ca2+ signaling factors: Involvement of protein kinase C (1999)
    Springer
    Molecular and cellular biochemistry 198 (1999), S. 101-107 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; Ca2+-binding protein ; protein kinase C ; Ca2+signaling ; gene expression ; H4-II-E hepatoma cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of hepatic Ca2+-binding protein regucalcin in the cloned rat hepatoma cells (H4-II-E) was investigated. The change in regucalcin mRNA levels was analyzed by Northern blotting using rat liver regucalcin complementary DNA (0.9 kb of open reading frame). Regucalcin mRNA was expressed in H4-II-E hepatoma cells. This expression was clearly stimulated in the presence of serum (10% fetal bovine serum). Bay K 8644 (2. 5 × 10-6 M), a Ca2+ channel agonist, significantly stimulated regucalcin mRNA expression in the absence or presence of 10% serum. Dibutyryl cyclic AMP (10-3 M) did not have a stimulatory effect on the regucalcin mRNA expression. The presence of phorbol 12-myristate 13-acetate (PMA; 10-6 M) or estrogen (10-8 M) caused a significant increase in regucalcin mRNA levels in the hepatoma cells cultured in serum-free medium, while insulin (5 × 10-9 M) or dexamethasone (10-6 M) had no effect. Bay K 8644-stimulated regucalcin mRNA expression in the hepatoma cells was completely blocked in the presence of trifluoperazine (10-5 M), an antagonist of calmodulin, or staurosporine (10-7 M), an inhibitor of protein kinase C. The stimulatory effect of PMA was clearly inhibited in the presence of stauroporine. The present study demonstrates that regucalcin mRNA is expressed in the transformed H4-II-E hepatoma cells, and that the expression is stimulated through Ca2+-dependent signaling factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006996506238
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Posttranscriptional regulation of urokinase receptor gene expression in human lung carcinoma and mesothelioma cells in vitro (1999)
    Springer
    Molecular and cellular biochemistry 199 (1999), S. 189-200 
    Details
    ISSN: 1573-4919
    Keywords: lung ; cancer ; urokinase ; receptor ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The urokinase-type plasminogen activator (uPA) interacts with its receptor (uPAR) to promote proteolysis as well as cell proliferation and migration. These functions contribute to the pathogenesis of neoplastic growth and invasiveness. Expression of uPAR in tumor extracts also inversely correlates with prognosis in many forms of cancer. In this study, we sought to determine if differences in uPAR expression were distinguishable between cultured human lung carcinoma and malignant mesothelioma subtypes. We also sought to determine if, as in malignant mesothelioma cells, uPAR expression is regulated at the posttranscriptional level in cultured malignant lung carcinoma cells. Using 125I-uPA binding and ligand blotting techniques, uPAR was expressed by phenotypically diverse lung carcinoma cell lines, including the H460, H157 and H1395 non-small cell lines and the H146 small cell lung carcinoma line. Increased uPAR expression was also detected in spindle-shaped (M33K) and epithelioid (M9K and MS-1) malignant mesothelioma cells. Selected mediators, including TGF-β, TNF-α, LPS and PMA, uniformly enhanced uPAR expression in each of the tumor cell lines. Steady state uPAR mRNA expression was determined by RNase protection assay and correlated directly with the changes in cell surface uPAR expression. By gel mobility shift and UV-cross linking assays, a uPAR mRNA binding protein (uPAR mRNABp) implicated in the posttranscriptional control of message stability, was identified in each of the cell lines. Expression of uPAR and its message in cultured lung carcinoma and malignant mesothelioma cells is similarly influenced by effectors present in the tumor microenvironment. Regulation of the uPAR message occurs at the posttranscriptional level in cultured small and non-small cell lung carcinoma cells as well as spindle-shaped and fibrous malignant mesothelioma cell lines. Posttranscriptional regulation of uPAR in all these cells involves the interaction of the uPAR mRNABp with uPAR mRNA, which promotes uPAR mRNA destabilization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006914800447
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    The Glycophorin A Gene Family in Gorillas: Structure, Expression, and Comparison with the Human and Chimpanzee Homologues (1997)
    Springer
    Biochemical genetics 35 (1997), S. 59-76 
    Details
    ISSN: 1573-4927
    Keywords: glycophorins ; gorilla ; evolution ; gene family ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Homologues of MN blood group antigens, encoded by members of the glycophorin A (GPA) gene family, are expressed in man, anthropoid apes, and some species of Old World monkeys. Previous studies had shown that a three-gene framework, most closely related to that in man, is present in the chimpanzee. Here we report the genomic structure, transcript map, and protein expression of the GYPA locus in gorillas. Compared to the corresponding human and chimpanzee homologues, gorilla GPA, GPB, and GPB/E genes each showed a high degree of sequence identity, with the same exon-intron organization. However, the expression of exons III, IV, or V encoding the extracellular or membrane domains of homologous glycophorins varied among the three species. Gorilla GPA and GPB/E genes were unique in that the former occurred in two allelic forms with or without the expression of exon III, whereas the latter contained one (ψ exon III) instead of two silenced exons (ψ exons III and IV). Differences from human but not chimpanzee GPA also included the presence of a hybrid M/N epitope and the absence of the sequon for N-glycosylation. Owing to the retention of a functional exon III, gorilla GPB was more similar to chimpanzee GPB than human GPB. A transspecies allele was identified in the gorilla that gave rise to the Henshaw (He)-like antigen similar to that found in man. These results provide further insight into the model for evolution of the GPA gene family, indicating that the mechanisms underlying inter- and intraspecific polymorphism of glycophorins could predate the divergence of gorillas as the consequence of gene duplication and diversification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022212630370
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Nitrogen Addition to an O-1 Tool Steel (1999)
    Springer
    Journal of materials synthesis and processing 7 (1999), S. 311-319 
    Details
    ISSN: 1573-4870
    Keywords: Iron ; carbon ; nitrogen ; microstructure ; characterization ; HIP-drip
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A new processing technique makes nitrogen alloying possible by adding nitrogen under elevated nitrogen pressure to prealloyed Fe-C ingots during continuous casting, producing a whole new class of precipitation-free, iron–carbon–nitrogen alloys. When both carbon and nitrogen bulk concentration levels exceeded 0.5 wt%, a duplex fcc-/(bcc-bct-) Fe microstructure resulted that is iron carbide- and nitride-free. With increasing carbon and nitrogen concentrations, there was an increase in the retained fcc-Fe phase. In cooling rate studies, increasing carbon and nitrogen concentrations shifted the knee of the fcc-Fe-to-bcc-Fe phase time–temperature–transformation (T–T–T) curve to longer times. Hardness, compression strength, and wear resistance increased with increasing carbon and nitrogen concentrations and were superior to iron–carbon alloys without the nitrogen addition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021877121902
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Novel methods for adenovirus-mediated gene transfer to blood vessels in vivo (1997)
    Springer
    Molecular and cellular biochemistry 172 (1997), S. 37-46 
    Details
    ISSN: 1573-4919
    Keywords: gene transfer ; gene expression ; adenovirus ; blood vessel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Adenovirus-mediated gene transfer is a promising method for studies of vascular biology and potentially for gene therapy. Intravascular approaches for gene transfer to blood vessels in vivo generally require interruption of blood flow and have several limitations. We have used two alternative approaches for gene transfer to blood vessels in vivo using perivascular application of vectors. First, replication-deficient adenovirus expressing nuclear-targeted bacterial b-galactosidase was injected into cerebrospinal fluid via the cisterna magna of rats. Leptomeningeal cells over the major arteries were efficiently transfected, and adventitial cells of large vessels and smooth muscle cells of small vessels were occasionally stained. When viral suspension was injected with the rat in a lateral position, the reporter gene was expressed extensively on the ipsilateral surface of the brain. Thus, adenovirus injected into cerebrospinal fluid provides gene transfer in vivo to cerebral blood vessels and, with greater efficiency, to perivascular tissue. Furthermore, positioning of the head may ‘target’ specific regions of the brain. Second, vascular gene delivery was accomplished by perivascular injection of virus in peripheral vessels. Injection of the adenoviral vector within the periarterial sheath of monkeys resulted in gene transfer to the vessel wall that was substantial in magnitude although limited to cells in the adventitia. Approximately20% of adventitial cells expressed the transgene, with no gene transfer to cells in the intima or media. These approaches may provide alternative approaches for gene transfer to blood vessels, and may be useful for studies of vascular biology and perhaps vascular gene therapy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006803202179
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Differential display: Identifying genes involved in cardiomyocyte proliferation (1997)
    Springer
    Molecular and cellular biochemistry 172 (1997), S. 111-120 
    Details
    ISSN: 1573-4919
    Keywords: differential display ; cardiac development ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract An estimated 15,000 different mRNA species are expressed in a typical mammalian cell. The differential expression of mRNAs in both a temporal and cell-specific manner determines the fate of the cell and creates the organism. Analysis of this differential gene expression has become a central aim of many laboratories attempting to understand the mechanisms underlying various biological processes. Currently, we are using a technique called differential display to analyze the differential expression of genes in cardiomyocytes. Differential display is a rapid and powerful technique that was introduced by Liang and Pardee in 1992. Since that time, it has been successfully applied by several groups, and it is quickly becoming a standard method for studying differential gene expression. Here, we present a detailed article discussing the differential display methodology and how we have utilized it to identify potential genes involved in cardiomyocyte proliferation. Furthermore, we have provided a list of materials and supplied examples of data obtained, in an effort to allow the reader to perform the technique with success in their own laboratory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006819705814
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Increased gene expression of plasminogen activators and inhibitors in left ventricular hypertrophy (1997)
    Springer
    Molecular and cellular biochemistry 176 (1997), S. 265-271 
    Details
    ISSN: 1573-4919
    Keywords: plasminogen activators ; plasminogen activator inhibitors ; gene expression ; left ventricular hypertrophy ; pressure overload
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract In the early stages of left ventricular hypertrophy (LVH) acute adaptive changes occur in the coronary vasculature as it remodels. Plasminogen activators (PAs) and inhibitors (PAIs) have the potential effects of proteolytic degradation that is relevant to tissue remodeling and angiogenesis. Our study focused on the possible roles of PAI-1, PAI-2, uPA and tPA in myocyte hypertrophy and angiogenesis in the early and late stages of pressure overload induced left ventricular hypertrophy (LVH). We divided seventeen adult swine, weighing 24.2 ± 6.5 kg, into four groups: control, sham-operated, early LVH and late heart failure LVH group. At surgery we placed a fixed constrictor on the ascending aorta immediately above the aortic valve. This increased LV systolic pressure from 133 ± 15 to 193 ± 24 mm Hg after the surgery. We subdivided the early group into groups of 3 animals each that we euthanized at 8, 24 and 72 h after operation and obtained heart samples for analysis. In the late heart failure group individual animals were euthanized at 55, 59, 62 and 72 days after the detection of congestive heart failure. We also obtained tissue samples from the control and sham-operated swine. Sections for histologic analysis were fixed in 10% buffered formalin. We isolated RNA, size fractionated it using 1% formaldehyde-agarose gel electrophoresis and then did Northern blots. The mRNAs from both PAI-1 and PAI-2 showed a remarkable increase at 8 and 24 h after acute aortic constriction and returned to control by 72 h. Regional differences showed that most of the increases were in the endocardium. Three animals in the late heart failure LVH group were determined to be in congestive heart failure at about 2 months after the onset of aortic constriction. In these animals PAI-1 and PAI-2 were increased in both the left and right ventricles but remained low in an animal of the same elevation in aortic pressure seen by the LV who did not have congestive failure. These data suggest that PA and PAI gene expressions change before morphologic changes occur in the early stages of developing LVH. Also at the time of onset of congestive heart failure this increased expression reappears. PAs and PA inhibitors mRNA levels vary in the different regions of the heart reflecting changing wall stresses. Thus, the PAs and PA inhibitors may play an important role in angiogenesis that occurs during the early stages of LVH. The increased expression in the late stage of LVH may reflect further changes in wall stresses since these animals also showed overt clinical signs of heart failure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006813531576
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Protein tyrosine phosphatase gene expression analysis in Swiss 3T3 fibroblasts (1998)
    Springer
    Molecular and cellular biochemistry 178 (1998), S. 157-162 
    Details
    ISSN: 1573-4919
    Keywords: protein tyrosine phosphatases ; gene expression ; degenerate deoxyoligonucleotides ; RT-PCR ; Swiss 3T3 fibroblasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The aim of this study was to identify protein tyrosine phosphatases (PTPs) expressed in Swiss 3T3 fibroblasts and to examine their expression levels as well as to characterize quantitative aspects of RT-PCR based on degenerate deoxyoligonucleotides. By using an RT-PCR assay based on degenerate deoxyoligonucleotide primers, expression of mRNAs for two cytoplasmic- and six transmembrane-type PTPs in Swiss 3T3 cells was detected. The sequences of two of them are new. Among nine analyzed PTPs expressed to widely varied extends, only three have mRNA levels high enough to be seen on Northern blots with 10 µg of total RNA per lane. The frequencies with which the examined PTPs are represented among the PCR amplification products, correlate stronger with the primer fidelity, defined as the number of mismatches between the primer- and the cDNA target-sequences, rather than with the PTP expression levels. In conclusion, an RT-PCR assay based on degenerate primers can be successfully used to sample the expressed PTPs and to identify new members of this gene family. However, reliable quantification of their mRNA levels can only be achieved using the classical approaches, like Northern, RNase protection assay or non-degenerate quantitative RT-PCR.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006897629337
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Differential regulation of GRP78 and GLUT1 expression in 3T3-L1 adipocytes (1996)
    Springer
    Molecular and cellular biochemistry 162 (1996), S. 51-58 
    Details
    ISSN: 1573-4919
    Keywords: metabolism ; glucose transporter ; adipocytes ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract We tested the hypothesis that the constitutive glucose transporter (GLUT 1) in 3T3-L 1 adipocytes belongs to the family of glucose-regulated proteins which are transcriptionally regulated by glucose deprivation. Using cDNA probes for both GRP78 (BiP) and GLUT1, we show that the level of GRP78 mRNA increased by 15-fold within 24 h of glucose deprivation with little change in GLUT1 mRNA. The elevated GRP78 mRNA in turn led to a time-dependent increase in GRP78 protein. While glucose deprivation did not alter the expression of the normal glycoform of GLUT 1, a lower molecular weight glycoform accumulated with extended deprivation. Mannose and fructose, but not galactose, prevented the induction of GRP78 and accumulation of the abnormal GLUT1. Because GRP78 acts as a chaperone in other cell systems, we also sought evidence to support this activity in 3T3-L1 adipocytes. Using the technique of co-immunoprecipitation, we demonstrate that GRP78 bound several proteins unique to the glucose-deprived state. No deprivation-specific proteins could be detected in association with GLUT 1. These data lead us to conclude that GLUTl does not display characteristics of the glucose-regulated proteins, at least in 3T3-L1 adipocytes, a widely used model for differentiation, hormone action, and nutrient control. However, the mechanisms for activating traditional members of this family appear intact.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00250995
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Gene expression after short periods of coronary occlusion (1998)
    Springer
    Molecular and cellular biochemistry 186 (1998), S. 43-51 
    Details
    ISSN: 1573-4919
    Keywords: myocardial ischemia ; gene expression ; growth factors ; phospholamban ; calsequestrin heat shock proteins ; preconditioning ; stunning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Brief periods of coronary occlusion render the affected myocardium more tolarant to the otherwise devastating effects of long coronary occlusion. Besides this phenomena, called ischemic preconditioning, short periods of ischemia cause a regional dysfunction, namely myocardial stunning. The molecular mechanisms of both syndromes are not very well understood. We therefore investigated the expression of genes which may be involved in cardioprotection or repair processes.Using our porcine model of ischemia and reperfusion we were able to show an induction of genes coding for transcription factors (proto-oncogenes), for proteins involved in repair processes (heat shock genes), for proteins implicated in the calcium homeostasis (calcium-handling genes) and for growth factors. We could show that the increased mRNA levels are due to an enhanced transcriptional activity and not to a prolonged half-life of the transcripts. The angiogenic growth factor vascular endothelial growth factor (VEGF) represents an exception. It exhibits - in addition to a HIF-motif (Hypoxia Inducible Factor) in its promoter/enhancer - a protein binding region in its 3′ UTR which when occupied renders the mRNA more stable. However to what extent the expression of the distinct genes contributes to the cardioprotective effect of ischemic preconditioning or myocardial stunning can only be presumed. Increased mRNA stability can be confered via adenosine which is produced during ischemia by ATP-breakdown. The demasking of unknown genes - via differential display reverse transcription polymerase chain reaction (DDRT-PCR) - should provide a more comprehensive view of the mechanisms underlying both processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006853432678
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Transcriptional modulation of the human complement factor I gene in Hep G2 cells by protein kinase C activation (1999)
    Springer
    Molecular and cellular biochemistry 201 (1999), S. 111-123 
    Details
    ISSN: 1573-4919
    Keywords: complement factor I ; TPA ; protein kinase C ; gene expression ; Hep G2 cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract This study examined the role of the protein kinase C (PKC) signalling pathway in the regulation of expression of human complement factor I (CFI) gene. The production of CFI by Hep G2 cells was enhanced in a dose- and time-dependent fashion by 12-O-tetradecanoyl-1,2-phorbol 13-acetate (TPA), a potent PKC activator. 4α-phorbol didecanoate, an inactive phorbol ester, had no effect on CFI synthesis. The TPA-dependent increase in CFI secretion was correlated with an increase in CFI mRNA levels. Forskolin, a cAMP-inducing agent, augmented the TPA response. W7, an inhibitor of protein kinase A and genistein, an inhibitor of protein tyrosine kinase(s) both did not prevent the increase in CFI expression mediated by TPA. However, calphostin C, a specific inhibitor of PKC, abolished the TPA-induced increase in CFI mRNA levels. Down regulation of intracellular PKC levels by prior exposure of Hep G2 cells to a high concentration of TPA also blocked the increase in CFI mRNA levels induced by TPA suggesting that the TPA effects were mediated via activation of PKC. mRNA decay studies indicated that the half-life of CFI mRNA in TPA-induced cells was not significantly different from control. Nuclear run-on transcriptional assays on the other hand demonstrated that whereas the CFI gene is transcribed under basal conditions in Hep G2 cells, TPA induced a 3-4 fold increase in the transcription rate of CFI gene in 24 h. The transcription rate of GAPDH gene did not change, indicating that the effects were not general on gene transcription. Transient transfections of Hep G2 cells with chloramphenicol acetyltransferase reporter gene (CAT) constructs containing a series of sequential 5′ deletions of the CFI promoter and CAT assays showed that the sequence between -136 and -130, containing an AP-1 consensus sequence (TGAGTCA) was required for the TPA response. This observation was substantiated by the finding that mutation of this AP-1 site to TttaTCA or TtAtcCA abolished the TPA responsiveness. The enhancement of the activity of transfected chimeric CAT constructs by TPA was abrogated by calphostin C and by pyrrolidine dithiocarbamate (an inhibitor of NF-κB and AP-1 transactivation). These results indicate that TPA regulation of CFI gene requires PKC signalling and is mediated by via a TPA response element (TRE) in the CFI promoter region located at -136/-130 and involves the transactivation of AP-1 and NF-κB transcription factors. We suggest that PKC may be one of the intracellular pathways that control CFI gene expression and that cellular processes (involving growth factors, hormones, cytokines etc.) that activate PKC may upregulate the expression of the CFI gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007064602321
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin and microsomal Ca2+-ATPase regulation in rat brain: Attenuation with increasing age (1999)
    Springer
    Molecular and cellular biochemistry 200 (1999), S. 43-49 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; Ca2+-ATPase ; brain microsomes ; aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of calcium-binding protein regucalcin and its effect on the microsomal Ca2+-ATPase activity in rat brain tissues was investigated. The expression of regucalcin mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in brain tissues using rat regucalcin-specific primers. Regucalcin concentration in the brain tissues was about 5 × 10-9 M as measured using enzyme-linked immunoadsorbent assay (ELISA), and this level was lowered with increasing age (50 weeks old). The presence of regucalcin (10-9 to 10-7 M) in the enzyme reaction mixture caused a significant decrease in Ca2+-ATPase activity in the brain microsomes of young rats (5 weeks old). Meanwhile, the enzyme activity was not significantly altered by the addition of calmodulin (1 or 50 μg/ml), calbindin (1 or 10 μg/ml), and S-100 A protein (5 or 25 μg/ml), which are other Ca2+-binding proteins in rat brain. The effect of regucalcin to inhibit microsomal Ca2+-ATPase activity was weakened in the brain of rats with increasing age (50 weeks old). The present study demonstrates that regucalcin is expressed in the brain, and that it can uniquely inhibit Ca2+-ATPase activity in the brain microsomes of rats. The findings suggest that regucalcin plays a role in the regulation of microsomal Ca2+-ATPase activity in rat brain tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006928402184
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Cost-Effective Nutrient Reductions to the Baltic Sea (1997)
    Springer
    Environmental and resource economics 10 (1997), S. 341-362 
    Details
    ISSN: 1573-1502
    Keywords: Baltic Sea ; eutrophication ; nitrogen ; phosphorus ; cost effective
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract Due to eutrophication caused by heavy loads of nitrogen and phosphorus, the biological conditions of the Baltic Sea have been disturbed: large sea bottom areas without any biological life, low stocks of cods, and toxic blue green algaes. It is recognized that the nitrogen and phosphorus loads to the Baltic Sea must be reduced by 50% in order to restore the sea. The main purpose of this paper is to calculate cost effective nitrogen and phosphorus reductions to the Baltic Sea from the nine countries surrounding the Baltic Sea. The results show a significant difference in minimum costs of decreasing nitrogen and phosphorus loads to the Sea: approximately 12 000 millions of SEK per year and 3 000 millions of SEK respectively for reductions by 50%. It is also shown that a change from a policy of cost-effective nutrient reductions to a policy where each country reduces the nutrient loads by 50% increase total costs for both nitrogen and phosphorus reductions by about 300%. The results are, however, sensitive to several of the underlying assumptions and should therefore be interpreted with much caution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026497515871
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Variation of Piperidine Alkaloids in Ponderosa (Pinus poderosa) and Lodgepole Pine (P. contorta) Foliage from Central Oregon (1998)
    Springer
    Journal of chemical ecology 24 (1998), S. 815-827 
    Details
    ISSN: 1573-1561
    Keywords: Piperidine alkaloids ; pinidine ; euphococcinine ; foliar chemistry ; nitrogen ; Pinus ponderosa ; Pinus contorta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We quantified 2,6-disubstituted piperidine alkaloids in Pinus ponderosa and P. contorta needles from three forest sites in April, June, August, and December. Alkaloids were detected on at least one date in 71% of the ponderosa pine and in 29% of the lodgepole pine trees sampled. Pinidine was the major alkaloid constituent of ponderosa pine, while euphococcinine was the predominant compound in lodgepole pine. For ponderosa pine, total alkaloid concentrations were very low at two sites on all dates. At the third site, concentrations were variable but significantly higher on all dates. Total alkaloid concentrations in previous-year foliage from this site were highest in April, then significantly lower from June through December. Current-year foliage collected in August and December had significantly higher alkaloid concentrations than previous-year foliage on the same dates. Variation in foliar nitrogen concentrations accounted for some of the alkaloid variation in current-year foliage sampled in August.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022369416745
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Sulphur and nitrogen deposition in Norway, status and trends (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 623-628 
    Details
    ISSN: 1573-2932
    Keywords: monitoring ; deposition ; sulphur ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract The total deposition of sulphur (S) and nitrogen (N) components in Norway during the period 1988–1992 has been estimated on the basis of measurement data of air- and precipitation chemistry from the national monitoring network. There are large regional variations in depositions with highest values in the southwestern part of Norway. Time series analysis of annual mean concentrations of sulphur dioxide (SO2) and sulphate (SO4 −−) in air, non marine SO4 −−, nitrate (NO3 −) and ammonium (NH4 +) in precipitation, shows a significant reduction in the S concentrations both in air and precipitation. In precipitation the concentrations are reduced by 30–45 percent in Southern Norway and 45–55 percent in Central and Northern Norway. Even larger reductions are observed in air concentrations with 50–65 percent reduction in Southern Norway and 65–88 percent reduction further north. For N components there are generally no significant trends in concentration levels nor in precipitation or air. The observed trends are comparable with reported trends in emission.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00476898
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Indirect effects of N and S deposition on a Norway spruce ecosystem. An update of findings within the Skogaby project (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 1613-1622 
    Details
    ISSN: 1573-2932
    Keywords: Deposition ; ecosystem ; nitrogen ; Norway spruce ; nutrient cycling ; production ; root function ; sulphur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract In this paper we try to interpret results from different investigations where an ecosystem with Norway spruce was manipulated with increased N and S deposition via the soil system. The site, in Skogaby in Southwest Sweden, had 1989–93 an annual deposition of 9 kg NH4-N; 7 kg NO3-N and 20 kg SO4-S ha−1. The stand was treated during 6 years with 100 kg N and 114 kg S ha− y−1 in the form of ammonium sulphate (NS treatment). The stand reacted with increased above ground production of 31% after 3 years of treatment. The uptake above ground of N was 155 kg ha−1 higher than in the control. Those trends were even stronger after 6 years of treatment. There were no decreases in the uptake of P, K, Ca or Mg (but for B) after 3 or 6 years of NS-treatment. Needle macro nutrient concentrations in relation to N decreased for several nutrients due to dilution effects. As result of the NS treatment pH increased markedly in the litter layer, and less, but significantly, in the humus layer. A decrease in pH value by about 0.3 units was found in the rest of the soil profile down to 50 cm. Dry mass of needle litter fall and litter layer both increased as a result of 6 years of NS-treatment. After three years of treatment 77–80% of all living fine roots in both control and NS treatment were found in the humus layer and the upper 10 cm of the mineral soil. The amount of living fine roots in the humus layer of NS-treated trees decreased to about one third of the control, and the amount of dead fine roots increased by 150% compared with untreated trees after 6 years of treatment. It is argued that the decreased amount of living and increased amount of dead fine roots not necessarily are indications of decreased root vitality. It can also be explained by increased root turnover rate and decreased decomposition rates of N rich new and old fine root litter. No inorganic N was leached from the control plots whereas the NS treated plots started to leach NO3 the second year of treatment. During 1989–1993 a total of 44 kg NO3-N and 30 kg NH4-N per ha was lost from the system which means that 88% of the N supplied was retained by the ecosystem. At first SO4 was adsorbed in the soil, but after five years of treatment the output was almost equal to the input.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00477211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Acid deposition: Perspectives in time and space (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 15-24 
    Details
    ISSN: 1573-2932
    Keywords: Acid deposition ; global change ; Asia ; fertilizer ; nitrogen ; sulfur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Most acid-deposition investigations have been concerned with the impact of nitrogen oxides (NOx) and sulfur dioxide (SO2) emissions on Europe and North America. This paper examines three issues beyond this central focus. Major conclusions are 1) ammonia (NH3) emissions and subsequent nitrogen (N) accumulation in terrestrial ecosystems have the potential to generate significant acidification in terrestrial and aquatic ecosystems; 2) sulfur (S) and N accumulation in environmental reservoirs will not only result in significant and extensive acidification but will also impact the earth's radiation balance, tropospheric oxidizing capacity, ecosystem nutrient balance and groundwater quality; and 3) future emissions will substantially increase in the developing world, especially in Asia. By 2020, Asian emissions of SO2, NOx and NH3 will be equal to or greater than the combined emissions from Europe and North America.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00483685
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Global forest systems: An uncertain response to atmospheric pollutants and global climate change? (1995)
    Springer
    Water, air & soil pollution 85 (1995), S. 101-110 
    Details
    ISSN: 1573-2932
    Keywords: carbon ; nitrogen ; sulfur ; biogeochemistry ; mitigation ; global change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Forest systems cover more than 4.1×109 ha of the Earth's land area. The future response and feedbacks of forest systems to atmospheric pollutants and projected climate change may be significant. Boreal, temperate and tropical forest systems play a prominent role in carbon (C), nitrogen (N) and sulfur (S) biogeochemical cycles at regional and global scales. The timing and magnitude of future changes in forest systems will depend on environmental factors such as a changing global climate, an accumulation of CO2 in the atmosphere, and increase global mineralization of nutrients such as N and S. The interactive effects of all these factors on the world's forest regions are complex and not intuitively obvious and are likely to differ among geographic regions. Although the potential effects of some atmospheric pollutants on forest systems have been observed or simulated, large uncertainty exists in our ability to project future forest distribution, composition and productivity under transient or nontransient global climate change scenarios. The potential to manage and adapt forests to future global environmental conditions varies widely among nations. Mitigation practices, such as liming or fertilization to ameliorate excess NOx or SOx or forest management to sequester CO2 are now being applied in selected nations worldwide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00483692
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...