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
Filter
  • Rat  (524)
  • Calcium  (195)
  • Development
  • Scanning electron microscopy
  • man
  • Springer  (1,107)
  • American Association for the Advancement of Science
  • American Geophysical Union
  • Irkutsk : Ross. Akad. Nauk, Sibirskoe Otd., Inst. Zemnoj Kory
  • Krefeld : Geologischer Dienst Nordhein-Westfalen
  • Wiley
  • 2015-2019
  • 2005-2009
  • 1985-1989  (450)
  • 1975-1979  (336)
  • 1970-1974  (321)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Lack of effect of dietary minerals on liver cholesterol concentrations in rats (1989)
    Springer
    European journal of nutrition 28 (1989), S. 316-318 
    Details
    ISSN: 1436-6215
    Keywords: dietarycalcium ; dietarymagnesium ; dietaryphosphorus ; serumcholesterol ; livercholesterol ; fecalbile acids ; rats ; Calcium ; Magnesium ; Phosphor ; Serumcholesterin ; Lebercholesterin ; Gallensäure im Kot ; Ratten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Während 28 Tagen wurden an Ratten cholesterinfreie halbgereinigte Diäten, die verschiedene Konzentrationen von Calcium (0,13–0,75 g/100 g), Magnesium (0,02–0,04 g/100 g) oder Phosphor (0,2–0,8 g/100 g) enthielten, verabreicht. Die unterschiedlichen Mineralkonzentrationen hatten keinen Einfluß auf Serum- und Lebercholesterin oder die Ausscheidung von Gallensäuren im Kot.
    Notes: Summary Female rats were fed cholesterol-free, purified diets with different concentrations of calcium (0.13–0.75%, w/w), magnesium (0.02 or 0.04%) or phosphorus (0.2–0.8 %) as the only dietary variable. After 28 days, no effects of the minerals were found on liver cholesterol concentrations and rates of fecal excretion of bile acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02019394
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Identification of brain tumours in rats using laser-induced fluorescence and haematoporphyrin derivative (1989)
    Springer
    Lasers in medical science 4 (1989), S. 241-249 
    Details
    ISSN: 1435-604X
    Keywords: Brain tumour ; Rat ; Detection ; Fluorescence ; Laser ; Haematoporphyrin derivative
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract Laser-induced fluorescence has been used for the identification of brain tumours in rats, which have been previously given tumour-seeking haematoporphyrin derivative. A pulsed nitrogen laser (λ=337 nm) was used in conjunction with an optical multichannel analyzer. For both inoculated RG-2 and TCVC rat-brain-tumour models, the blue autofluorescence was strongly reduced in the tumour compared with normal brain tissue, and at the same time the characteristic red-drug signal increased. The contrast between tumour and normal tissue was strongly enhanced by forming the ratio between the two signals. Implications for possible improvement of tumour delineation in brain tumour surgery are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02032454
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Iron chelators of the pyridoxal isonicotinoyl hydrazone class (1989)
    Springer
    BioMetals 2 (1989), S. 161-167 
    Details
    ISSN: 1572-8773
    Keywords: Fe chelation ; Thalassemia ; Fe overload ; Calcium ; Magnesium ; Zinc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary Formation constants for the calcium(II), magnesium(II) and zinc(II) complexes of the orally effective iron chelator, pyridoxal isonicotinoyl hydrazone (PIH) and three analogues, pyridoxal benzoyl hydrazone (PBH), pyridoxalp-methoxybenzoyl hydrazone (PpMBH) and pyridoxalm-fluorobenzoyl hydrazone (PmFBH) have been determined by potentiometry at 25\dg C andI=0.1 M [KNO3]. The four ligands bind calcium(II) weakly and magnesium(II) only slightly more strongly, as a l: l complex which is formed at pH \s〉 8. The chelation of zinc(II) for all the ligands studied was greater than that for calcium(II) and magnesium(II), with complexation generally becoming significant at about pH 5. Thus, chelation of zinc(II) but not calcium(II) or magnesium(II) at physiological pH, 7.4 may be expected. Calculated values of the concentration of uncomplexed metal ion indicate that the selectivity of these ligands towards Fe(III) is comparable to that of the clinically used chelator desferrioxamine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01142555
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Intra- and interspecies analyses of the carcinoembryonic antigen (CEA) gene family reveal independent evolution in primates and rodents (1989)
    Springer
    Journal of molecular evolution 29 (1989), S. 126-134 
    Details
    ISSN: 1432-1432
    Keywords: Carcinoembryonic antigen ; Evolution ; Gene family ; Human ; Rat ; Synonymous substitutions ; Silent molecular clock ; Evolutionary trees
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Various rodent and primate DNAs exhibit a stronger intra- than interspecies cross-hybridization with probes derived from the N-terminal domain exons of human and rat carcinoembryonic antigen (CEA)-like genes. Southern analyses also reveal that the human and rat CEA gene families are of similar complexity. We counted at least 10 different genes per human haploid genome. In the rat, approximately seven to nine different N-terminal domain exons that presumably represent different genes appear to be present. We were able to assign the corresponding genomic restriction endonuclease fragments to already isolated CEA gene family members of both human and rat. Highly similar subgroups, as found within the human CEA gene family, seem to be absent from the rat genome. Hybridization with an intron probe from the human nonspecific cross-reacting antigen (NCA) gene and analysis of DNA sequence data indicate the conservation of noncoding regions among CEA-like genes within primates, implicating that whole gene units may have been duplicated. With the help of a computer program and by calculating the rate of synonymous substitutions, evolutionary trees have been derived. From this, we propose that an independent parallel evolution, leading to different CEA gene families, must have taken place in, at least, the primate and rodent orders.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02100111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Influence of ethanol on calcium, inositol phospholipids and intracellular signalling mechanisms (1989)
    Springer
    Cellular and molecular life sciences 45 (1989), S. 407-413 
    Details
    ISSN: 1420-9071
    Keywords: Calcium ; inositol phospholipids ; Ca++ channels ; Ca++/Mg++-ATPase ; dihydropyridine receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Studies have implicated Ca++ in the actions of ethanol at many biochemical levels. Calcium as a major intracellular messenger in the central nervous system is involved in many processes, including protein phosphorylation enzyme activation and secretion of hormones and neurotransmitters. The control of intracellular calcium, therefore, represents a major step by which neuronal cells regulate their activities. The present review focuses on three primary areas which influence intracellular calcium levels; voltage-dependent Ca++ channels, receptor-mediated inositol phospholipid hydrolysis, and Ca++/Mg++-ATPase, the high affinity membrane Ca++ pump. Current research suggests that a subtype of the voltage-dependent Ca++ channel, the dihydropyridine-sensitive Ca++ channel, is uniquely sensitive to acute and chronic ethanol treatment. Acute exposure inhibits, while chronic ethanol exposure increases45Ca++-influx and [3H]dihydropyridine receptor binding sites. In addition, acute and chronic exposure to ethanol inhibits, then increases Ca++/Mg++-ATPase activity in neuronal membranes. Changes in Ca++ channel and Ca++/Mg++-ATPase activity following chronic ethanol may occur as an adaptation process to increase Ca++ availability for intracellular processes. Since receptor-dependent inositol phospholipid hydrolysis is enhanced after chronic ethanol treatment, subsequent activation of protein kinase-C may also be involved in the adaptation process and may indicate increased coupling for receptor-dependent changes in Ca++/Mg++-ATPase activity. The increased sensitivity of three Ca++-dependent processes suggest that adaptation to chronic ethanol exposure may involve coupling of one or more of these processes to receptor-mediated events.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01952021
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Borate control of protein secretion from Petunia pollen exhibits critical temperature discontinuities (1989)
    Springer
    Sexual plant reproduction 2 (1989), S. 11-14 
    Details
    ISSN: 1432-2145
    Keywords: Boric acid ; Pollen ; Petunia hybrida ; Temperature discontinuities ; Protein release ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Energy-driven protein secretion from Petunia hybrida pollen in 10% sucrose solution shaking culture does not change markedly with temperature, except over a narrow (6° C) temperature range with a midpoint at 17° C. Over this narrow temperature range, there is a very rapid increase from a low secretion plateau at low temperatures to a plateau of higher secretion at higher temperatures. Addition of calcium ions decreases the overall amount secreted, but does not change the critical temperature where the rapid rise in secretion is observed. Boric acid, when added to the culture, also decreases the overall amount released, but in a different way to calcium. While there is a sharp discontinuity at 17° C as before, the increase in protein release at this temperature is smaller than before. In addition, after a plateau at temperatures higher than 20° C, there is a second sharp increase in secreted protein over another narrow temperature range with a midpoint of 28° C, followed by another plateau at higher temperatures. The effects of calcium and boric acid are additive. The sharp discontinuities in protein release are interpreted in terms of lipid thermotropism in membranes and a boron involvement in the movement of proteins into the extending pollen tube membranes from secretory vesicles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00190113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Towards an in vitro bioassay for the self-incompatibility response in Brassica oleracea (1989)
    Springer
    Sexual plant reproduction 2 (1989), S. 277-280 
    Details
    ISSN: 1432-2145
    Keywords: Brassica oleracea ; Pollen germination ; In vitro assay ; Calcium ; Self-incompatibility ; S locus-specific glycoproteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Eluates of stigmas of Brassica oleracea that were known to contain S locus-specific glycoproteins (SLSG) discriminated between self and cross pollen in vitro in three different media. Discrimination was equally evident in experiments that were the in vitro equivalents of reciprocal pollinations. In a TAPS-buffered medium, self eluates depressed pollen germination in a dose-dependent manner. TAPS medium allowed a bioassay of the effects of SLSG in eluates because it optimized germination in a way that eliminated the complicating features of the stimulatory substances in the eluates. Stigma eluates affected percentage pollen germination and optimum calcium concentrations in vitro whether or not SLSG were present in the eluates, but differently in different media, and depending on whether the eluates were cross or self with respect to the pollen tested. Thus, the effect of stigma eluates on the in vitro germination of pollen in Brassica depends on the balance of stimulatory versus inhibitory substances in the eluates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00195588
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Long-term depletion of calcium and other nutrients in eastern US forests (1989)
    Springer
    Environmental management 13 (1989), S. 593-601 
    Details
    ISSN: 1432-1009
    Keywords: Acid precipitation ; Biomass nutrients ; Calcium ; Clearcutting ; Magnesium ; Nitrogen ; Phosphorus ; Potassium ; Soil leaching ; Soil nutrients ; Timber harvest ; Weathering ; Whole-tree harvest
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Both harvest removal and leaching losses can deplete nutrient capital in forests, but their combined long-term effects have not been assessed previously. We estimated changes in total soil and biomass N, Ca, K, Mg, and P over 120 years from published data for a spruce-fir site in Maine, two northern hardwood sites in New Hampshire, central hardwood sites in Connecticut and Tennessee, and a loblolly pine site in Tennessee. For N, atmospheric inputs counterbalance the outputs, and there is little long-term change on most sites. For K, Mg, and P, the total pool may decrease by 2%–10% in 120 years depending on site and harvest intensity. For Ca, net leaching loss is 4–16 kg/ha/yr in mature forests, and whole-tree harvest removes 200–1100 kg/ha. Such leaching loss and harvest removal could reduce total soil and biomass Ca by 20%–60% in only 120 years. We estimated unmeasured Ca inputs from rock breakdown, root-zone deepening, and dry deposition; these should not be expected to make up the Ca deficit. Acid precipitation may be the cause of current high leaching of Ca. Although Ca deficiency does not generally occur now in acid forest soils, it seems likely if anthropogenic leaching and intensive harvest removal continue.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01874965
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Melatonin accelerates reentrainment of the circadian rhythm of its own production after an 8-h advance of the light-dark cycle (1989)
    Springer
    Journal of comparative physiology 166 (1989), S. 97-102 
    Details
    ISSN: 1432-1351
    Keywords: Rat ; Melatonin ; Circadian rhythm ; 5-hydroxytryptophan
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rhythm in melatonin production in the rat is driven by a circadian rhythm in the pineal N-acetyltransferase (NAT) activity. Rats adapted to an artificial lighting regime of 12 h of light and 12 h of darkness per day were exposed to an 8-h advance of the light-dark regime accomplished by the shortening of one dark period; the effect of melatonin, triazolam and fluoxetine, together with 5-hydroxytryptophan, on the reentrainment of the NAT rhythm was studied. In control rats, the NAT rhythm was abolished during the first 3 cycles following the advance shift. It reappeared during the 4th cycle; however, the phase relationship between the evening rise in activity and the morning decline was still compressed. Melatonin accelerated the NAT rhythm reentrainment. In rats treated chronically with melatonin at the new dark onset, the rhythm had already reappeared during the 3rd cycle, in the middle of the advanced night, and during the 4th cycle, the phase relationship between the evening onset and the morning decline of the NAT activity was the same as before the advance shift. In rats treated chronically with melatonin at the old dark onset or in those treated with melatonin 8 h, 5 h and 2 h after the new dark onset during the 1st, 2nd and 3rd cycle, respectively, following the advance shift, the NAT rhythm reappeared during the 3rd cycle as well but in the last third of the advanced night only. Neither triazolam nor fluoxetine together with 5-hydroxytryptophan administered around the new dark onset facilitated NAT rhythm reentrainment after the 8-h advance of the light-dark cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00190214
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Effects of calcium channel blockers and DCMU on motility and the photophobic response of Gyrodinium dorsum (1989)
    Springer
    Archives of microbiology 151 (1989), S. 187-190 
    Details
    ISSN: 1432-072X
    Keywords: Calcium ; Calcium channel blocker ; Dinoflagellate ; Gyrodinium dorsum ; Motility ; Phytochrome ; Stop-response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of the calcium channel blockers, verapamil, diltiazem and lanthanum ions and the Ca2+ dependency on motility as well as the photophobic response (stop-response) of Gyrodinium dorsum were studied. At Ca2+ concentrations below 10-3 M, motility was inhibited. La3+ inhibits the stop-response, in contrast to verapamil and diltiazem. The only calcium channel blocker that increased the amount of non-motile cells was verapamil. The results indicate that motility are Ca2+ dependent and that the stop-responses of G. dorsum could be affected by extracellular Ca2+. Effects of the photosythesis inhibitor (DCMU) on the stop-response was also determined. With background light of different wavelength (614, 658 and 686 nm) the stop-response increased. DCMU inhibited this effect of background light. Negative results with the monoclonal antibody Pea-25 directed to phytochrome and the results with DCMU, indicate that the stop-response of G. dorsum is coupled to photosynthesis rather than to a phytochrome-like pigment. Oxygen evolution, but not cell movement, was completely inhibited by 10-6 M DCMU.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00413128
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Subcellular localization of calcium in sporangiophores of Phycomyces blackesleeanus (1989)
    Springer
    Archives of microbiology 152 (1989), S. 468-472 
    Details
    ISSN: 1432-072X
    Keywords: Calcium ; Phycomyces blakesleeanus ; Sporangiophore
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The in situ localization of Ca2+ in stage I sporangiophores of the fungus Phycomyces blakesleeanus was achieved with the potassium pyroantimonate technique. Precipitates of calcium-antimonate were present in mitochondria, vacuoles, endoplasmic reticulum and adjacent cytoplasm, “Golgi-like” bodies, and nuclei but not cell walls. Material treated with the calcium chelator EGTA lacked these precipitates. The preferential localization of Ca2+ in mitochondria, endoplasmic reticulum and vacuoles suggests that these organelles modulate the level of this cation in sporangiophores of P. blakesleeanus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446931
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Innervation of the arteriovenous anastomoses in the dog tongue (1989)
    Springer
    Cell & tissue research 258 (1989), S. 425-428 
    Details
    ISSN: 1432-0878
    Keywords: Arteriovenous anastomoses ; Vascular innervation ; Tongue ; Transmission electron microscopy ; Scanning electron microscopy ; Dog
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Profiles of nerve plexuses in the arteriovenous anastomoses of the dog tongue were investigated by both transmission and scanning electron microscopy. Three-dimensional morphology of the vascular nerves was examined after removal of the connective tissue components by the HCl-hydrolysis method. Tight bending and a rich nerve supply were the most characteristic features of the anastomosing channels. The tunica media consisted of an outer circular layer of typical smooth-muscle cells and an inner region containing longitudinal plicae of ramified smoothmuscle cells. The tunica adventitia was exclusively occupied by nerve bundles; fibroblasts were poorly developed. Numerous nerve bundles of variable size were coiled around the anastomosing channels, and occasional bundles ran crosswise over the U-shaped bent vessels.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00239464
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Development of Xenopus laevis skin glands producing 5-hydroxytryptamine and caerulein (1989)
    Springer
    Cell & tissue research 258 (1989), S. 483-489 
    Details
    ISSN: 1432-0878
    Keywords: Development ; Skin glands ; Peptides ; Metamorphosis ; Xenopus laevis (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The granular glands in Xenopus laevis skin are known to contain large quantities of biogenic amines and bioactive peptides which closely resemble mammalian brain-gut peptides. We studied the development of glands producing 5-hydroxytryptamine (5-HT) and caerulein using immunohistochemistry, HPLC-fluorometric systems and RIA. The immunoreactivities of 5-HT and caerulein were first detected in the spherical gland rudiments in the stratum spongiosum at St. 58 (Nieuwkoop and Faber stage), or at the beginning of metamorphosis. Both immunoreactivities appeared in the same rudiment at the same time. Some of the gland rudiments have a small lumen filled with both immunoreactive materials at St. 58–59. During the rest of the metamorphic period, the glands grow in size, accumulating immunoreactive materials in the lumen. The concentrations of 5-HT and caerulein in the skin of tadpoles were below 1 ng per mg wet tissue at St. 58–59, increased as metamorphosis proceeded and reached 63 and 134 ng per mg wet tissue at St. 66, or at the end of metamorphosis, respectively. The amphibian granular glands where large quantities of biogenic amines and hormone-like peptides are rapidly synthesized may provide a useful model for the study of the development of amine- and peptide-producing cells including neurons and paraneurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218860
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    An immunohistochemical study on the postnatal development of rat nasal-associated lymphoid tissue (NALT) (1989)
    Springer
    Cell & tissue research 256 (1989), S. 431-438 
    Details
    ISSN: 1432-0878
    Keywords: Mucosa ; Lymphoid tissue ; Nose ; Development ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study concerns the development of nasal-associated lymphoid tissue in the rat, using immuno- and enzyme-histochemical staining techniques on cryostat sections. Nasal-associated lymphoid tissue is present at birth as a small accumulation of mainly T lymphocytes and non-lymphoid cells; B cells are rare. Distinct areas of T and B cells appear at 10 days after birth; by that time high endothelial venules are also observed. Intra-epithelial lymphocytes are present, most of them being T-helper cells. ED1+ macrophages are seen throughout the tissue. The proportion of ED1+cells does not change during ontogeny. ED2+cells (tissue macrophages) are present predominantly at the border between the lymphoid tissue and the surrounding connective tissue, in all age-groups. ED3+mononuclear cells are scattered throughout the nasal-associated lymphoid tissue of young animals. Later on, the ED3+ cells migrate into the border-area between lymphoid and connective tissue. Ia+ non-lymphoid cells in the nasal lymphoid tissue increase in number during ontogeny. Only a few of them show acid phosphatase activity, indicating that the proportion of classical scavenger macrophages is low. Some of them may be antigen presenting (dendritic) cells. Ia+ dendritic cells also occur between the epithelial cells. Moreover, some epithelial cells express the Ia marker.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218901
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Cellular origin and distribution of transforming growth factor-β1 in the normal rat myocardium (1989)
    Springer
    Cell & tissue research 256 (1989), S. 553-558 
    Details
    ISSN: 1432-0878
    Keywords: Transforming growth factor (TGF)-β ; Myocardium ; mRNA ; Fibroblast ; Cardiomyocyte ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Transforming growth factor-β (TGF-β) is a biologically active polypeptide present in normal tissues as well as transformed cells. Two structurally related forms of this peptide are TGF-β 1 and TGF-β 2. Using freshly isolated cardiomyocytes and non-myocyte heart cells, and a [32P]-labelled cDNA probe to human TGF-β 1, we demonstrated that mRNA for TGF-β 1 could be detected only in the nonmyocyte fraction of heart cells. In the present study, the distribution of TGF-β 1 in the heart was determined by immunofluorescence staining by use of a polyclonal antibody to porcine TGF-β 1 in cryostat sections of rat heart. Immunofluorescence staining was intense around the blood vessels and radially diffuse in the surrounding myocardium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225603
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Expression of α and β tropomyosin subunits during early myogenesis in somites and limb buds of chick embryos (1989)
    Springer
    Cell & tissue research 256 (1989), S. 631-634 
    Details
    ISSN: 1432-0878
    Keywords: Development ; Skeletal muscle ; Tropomyosin ; Somites ; Limb buds ; Chick embryo
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The appearance of α and β subunits of skeletal tropomyosin in early myogenesis was studied histochemically using monoclonal antibody to α tropomyosin and affinity-purified polyclonal antibody to β tropomyosin. In muscle cells, in both somites and limb buds, the α and β subunits are simultaneously expressed and first appear in the somites at the 30–36 somites. The relatively greater amount of β than α tropomyosin found in early myogenesis is thus likely to result from a higher rate of β tropomyosin synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225613
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Morphological changes in the junctional complex of cells in the arachnoid layer of the rat after cold injury (1989)
    Springer
    Cell & tissue research 256 (1989), S. 303-307 
    Details
    ISSN: 1432-0878
    Keywords: Arachnoid cells ; Tight and gap junctions ; Cold injury ; Ultrastructure ; Freeze-fracture technique ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The junctional complexes of cells in the outer arachnoid layer overlying the cerebral cortex of 2-week-old rats were examined with freeze-fracture electron microscopy up to 60 min after transcranial cold injury to the dorsal surface of the brain. Within 30 min after injury, areas of gap and tight junctions with morphological features characteristic of junction formation and/or junction disruption were found scattered among normal junctional complexes in some arachnoid cells. Within 60 min after injury, tight junctions with features typical of less leaky zonulae occludentes were present in all arachnoid cells examined. These morphological features include increases in the number of tight junctional strands and the number of strand-to-strand anatomoses. Gap junctions were interspersed among the tight junctional strands, and many were completely encircled by the strands. The increase in the number and complexity of the tight junctional strands in response to brain injury may be the morphological basis for the maintenance of the cerebrospinal fluid-blood dural barrier.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218887
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Axonal tracing of autonomic nerve fibers to the superficial temporal artery in the rat (1989)
    Springer
    Cell & tissue research 256 (1989), S. 559-565 
    Details
    ISSN: 1432-0878
    Keywords: Retrograde tracing ; Immunocytochemistry ; Vascular innervation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The origin of nerve fibers to the superficial temporal artery of the rat was studied by retrograde tracing with the fluorescent dye True Blue (TB). Application of TB to the rat superficial temporal artery labeled perikarya in the superior cervical ganglion, the otic ganglion, the sphenopalatine ganglion, the jugular-nodose ganglionic complex, and the trigeminal ganglion. The labeled perikarya were located in ipsilateral ganglia; a few neuronal somata were, in addition, seen in contralateral ganglia. Judging from the number of labeled nerve cell bodies the majority of fibers contributing to the perivascular innervation originate from the superior cervical, sphenopalatine and trigeminal ganglia. A moderate labeling was seen in the otic ganglion, whereas only few perikarya were labeled in the jugular-nodose ganglionic complex. Furthermore, TB-labeled perikarya were examined for the presence of neuropeptides. In the superior cervical ganglion, all TB-labeled nerve cell bodies contained neuropeptide Y. In the sphenopalatine and otic ganglia, the majority of the labeled perikarya were endowed with vasoactive intestinal polypeptide. In the trigeminal ganglion, the majority of the TB-labeled nerve cell bodies displayed calcitonin gene-related peptide, while a small population of the TB-labeled neuronal elements contained, in addition, substance P. In conclusion, these findings indicate that the majority of peptide-containing nerve fibers to the superficial temporal artery originate in ipsilateral cranial ganglia; a few fibers, however, may originate in contralateral ganglia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225604
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Distribution of MAP 2 in dendritic spines and its colocalization with actin (1989)
    Springer
    Cell & tissue research 256 (1989), S. 447-456 
    Details
    ISSN: 1432-0878
    Keywords: MAP2 ; Actin ; Dendritic spines ; Spine apparatus ; Spine synapses ; Postsynaptic density ; Synaptic plasticity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of MAP2 and actin in dendritic spines of the visual and cerebellar cortices, dentate fascia, and hippocampus was determined by using immunogold electron microscopy. By this approach, we have confirmed the presence of MAP2 in dendritic spines and identified substructures within the spine compartment showing MAP2 immunoreactivity. MAP2 immunolabeling was mainly associated with filaments which reacted with a monoclonal anti-actin antibody. Also, by immunogold double-labeling we colocalized MAP2 with actin on the endomembranes of the spine apparatus, smooth endoplasmic reticulum, and in the postsynaptic density. Labeling was nearly absent in axons and axonal terminals. These results indicate that MAP2 is an actin-associated protein in dendritic spines. Thus, MAP2 may organize actin filaments in the spine and endow the actin network of the spine with dynamic properties that are necessary for synaptic plasticity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225592
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Distribution and frequency of neuro-epithelial bodies in post-natal rabbit lung: Quantitative study with monoclonal antibody against serotonin (1989)
    Springer
    Cell & tissue research 255 (1989), S. 353-362 
    Details
    ISSN: 1432-0878
    Keywords: Development ; Intrapulmonary chemoreceptor ; Immunocytochemistry ; Morphometry ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution, frequency and size of neuroepithelial bodies (NEB) were studied in lungs of rabbits during different stages of development (27-day fetus, newborn, 6, 11, 21, 28 and 56 days postnatally). NEB were visualized by immunostaining with monoclonal antibody against serotonin. Detailed quantitiation of NEB was performed by use of camera lucida drawings of immunostained serial sections from the same anatomical region, i.e. the lower lobe of the left lung. The total number of NEB was counted and expressed per epithelial length of airway, surface area and volume. The size of NEB defined as surface area as well as the position of NEB in relation to the airway bifurcations was assessed in airways of different sizes. The overall number and size of NEB were found to increase during the immediate perinatal period followed by a sharp decline at 56 days of age. The number of NEB peaked at 6 days postnatally (mean 175.5 NEB/mm3 of airway epithelium) and declined significantly (3.0 NEB/mm3) at 56 days of postnatal age. The size of NEB reached its maximum at 11 days (mean surface area 659.54 μm2, with the largest NEB measuring 1839.98 μm2). By 56 days of age, NEB became significantly smaller (mean surface area 177.29 μm2) consisting of small clusters of cells situated deep within the airway epithelium. At all ages, about half of all NEB (mean 47.6%) were localized within the small peripheral airways with up to 63.9% located at airway bifurcations. These findings indicate that the “functional activity” of NEB may be confined predominantly to the perinatal period. The postulated functions of NEB include those of intrapulmonary hypoxia-sensitive chemoreceptors and/or endocrine-paracrine activity in the lung. Such function(s) may be important during adaptation to extrauterine life as well as for growth and development of the lung.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224118
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    A scanning electron-microscopic study of the peripolar cell of the rat renal glomerulus (1989)
    Springer
    Cell & tissue research 257 (1989), S. 201-206 
    Details
    ISSN: 1432-0878
    Keywords: Peripolar cell ; Efferent arteriole ; Afferent arteriole ; Kidney ; Scanning electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The interior of Bowman's capsules of rat kidneys has been examined by scanning electron microscopy, and a distinctive population of cells around the exposed vascular poles of glomerular tufts were identified. The cells were situated in the annular groove at the root of the glomerulus, between the parietal epithelial cells and the podocytes. These peripolar cells were dendritic cells with long processes embracing the glomerular arterioles. Up to three peripolar cells were present at each vascular pole and they were mainly distributed in the glomeruli of the outer third of the renal cortex. This first detailed study of the surface morphology of the glomerular peripolar cell supports the suggestion that changes in the diameter of the polar region of the glomerular tuft may cause variations in stretching of the cuff of peripolar cells, and hence modulation of their secretory activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221651
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Localization of calcium and phosphorus in early predentin-matrix components by electron spectroscopic imaging (ESI)-analysis in rat molars (1989)
    Springer
    Cell & tissue research 255 (1989), S. 611-617 
    Details
    ISSN: 1432-0878
    Keywords: Mantle dentin matrix ; Electron spectroscopic imaging (ESI)-analysis ; Calcium ; Phosphorus ; Dentinogenesis ; Biomineralization ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The subcellular distribution of the inorganic elements calcium (Ca) and phosphorus (P) was studied in the first-formed dentin matrix during initial mineralization in neonatal rat molars. This most peripheral matrix region is comprised of a proteoglycan-rich ground substance, interwoven by a collagenous network, matrix vesicles, aperiodic fibrils derived from the dental basal lamina, and apical odontoblastic cell processes. All matrix components may possibly serve as templets for mineral deposition during initial calcification of first-formed mantle dentin and predentin. By means of the very sensitive ESI-analysis we studied the subcellular localization of Ca and P and their possible association with distinct organic extracellular matrix components and odontoblasts. Ca-signals were found in the ground substance, at striated collagen fibrils and plasma membranes of odontoblasts in the cuspal early matrix region, but occurred only sparsely in the ground substance of the more distal matrix region where odontoblast processes attach to aperiodic fibrils of the dental basal lamina. Ca was generally absent in matrix vesicles. In contrast, P-signals were found in matrix vesicles, at aperiodic fibrils and at the plasma membranes of odontoblasts. Ca and P co-localized at striated collagen fibrils (type I or II). These results suggest that striated collagen fibrils might serve as primary deposition sites for calcium phosphate during early biological calcification of organic extracellular macromolecules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218798
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Specific adhesion between pheochromocytoma (PC12) cells and adrenal medullary endothelial cells in co-culture (1989)
    Springer
    Cell & tissue research 256 (1989), S. 365-372 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal medullary endothelial cells ; Pheochromocytoma (PC12) cells ; Co-culture ; Cell surface extracts ; Adhesion ; Cell-cell interactions ; Bovine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Chromaffin cells in the adrenal medulla are found in close proximity to capillary endothelial cells, thereby forming the classical endocrine complex. To examine the possible chemical basis of their interaction in more detail, we have grown bovine adrenal medullary endothelial (BAME) cells in monolayer cultures and added to them pheochromocytoma (PC12) cells, a chromaffin tumor cell line of rats. The PC12 cells were chosen because of the similarities they share with adrenal medullary chromaffin cells. PC12 cells rapidly attached to BAME cells cultures, their rate of adhesion being significantly enhanced over binding of PC12 cells to either uncoated plates or to monolayers of unrelated cell cultures. Consistent with this observation, we noted that the extracellular matrix (ECM) derived from the BAME cells did not enhance PC12 cell adhesion and did not promote neurite sprouting as previously described for ECM derived from corneal endothelial cells. The specific adhesion between PC12 and BAME cells could be abolished by cell surface extracts derived from these two cells but not by extracts derived from unrelated cell types. This activity was heat-labile, sensitive to trypsin and, to a lesser extent, to neuraminidase. We therefore conclude that PC12 cells may interact with BAME cells by specific proteinaceous adhesive factors associated with their plasma membranes. These interactions might represent the formative role of cell-cell contacts in the organization of the developing adrenal gland.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218894
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Three-dimensional observation of the fibroblast-like cells associated with the rat myenteric plexus, with special reference to the interstitial cells of Cajal (1989)
    Springer
    Cell & tissue research 255 (1989), S. 343-351 
    Details
    ISSN: 1432-0878
    Keywords: SEM ; TEM ; Interstitial cell ; Myenteric plexus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An extensive cellular network becomes visible over the myenteric plexus of the rat after removal of the overlying tissues under the scanning electron microscope. The cells are mainly stellate and have many slender processes via which they interconnect. They form a three-dimensional network and are closely associated with the ganglia and nerve bundles, and also extend over the smooth muscle cells. They are considered to correspond to the interstitial cells of Cajal because of their peculiar arrangement and their topography. Transmission electron-microscopic evidence demonstrates that the majority of those cells have features of fibroblasts. Gap junctions and intermediate junctions are observed between these fibroblast-like cells, and also between them and smooth muscle cells. Examination of serial thin sections reveals that single fibroblast-like interstitial cells connect to both circular and longitudinal muscle cells via gap junctions. It is suggested that the network of interstitial cells conducts electrical signals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224117
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    The relationship between gastrin cells and bombesin-like immunoreactive nerve fibres in the gastric antral mucosa of guinea-pig, rat, dog and man (1989)
    Springer
    Cell & tissue research 257 (1989), S. 171-178 
    Details
    ISSN: 1432-0878
    Keywords: Gastrin ; Gastrin-releasing peptide ; Bombesin ; Stomach ; Autonomic innervation ; Immunohistochemistry ; Guinea pig ; Rat ; Dog ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The relationship between bombesin-like immunoreactive (bombesin-LI) nerve fibres and gastrin-LI G-cells was examined in gastric antral mucosa from guineapig, rat, dog and man using a double-labelling fluorescence immunohistochemical technique. The greatest density of bombesin-LI nerve fibres was found within the basal mucosa in all species and the density of innervation decreased towards the luminal surface. Most G-cells were in a band occupying approximately the middle third of the mucosa. The proportion of G-cells found within a distance of 2 μm from bombesin-LI nerve fibres was low in all species (6% in the guinea-pig, 22% in the rat, 14% in the dog, and 9% in the human). It is proposed that the neuropeptide released from bombesin-LI antral mucosal nerve fibres traverses distances of greater than several μm to reach the target G-cells. This may be achieved by passage through the mucosal microcirculation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221648
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Immunohistochemistry of vacuoles occurring in rat hepatocytes after retinol administration (1989)
    Springer
    Cell & tissue research 257 (1989), S. 263-268 
    Details
    ISSN: 1432-0878
    Keywords: Retinol ; Vacuoles ; Immunohistochemistry ; Plasma proteins ; Hepatocytes ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vacuoles occurring in rat hepatocytes after intraportal injection of retinol (33 or 67 μg) were examined immunohistochemically using respective antibodies against rat albumin, human retinol-binding protein, human ceruloplasmin, human α 1-antitrypsin, human transferrin, and human prealbumin as representative plasma proteins. The occurrence of the vacuoles reached a numerical maximum 30 min after injection of 67 μg retinol, followed by a temporal decrease. Hepatocytes from control rats, which had been intraportally injected with either blood plasma diluted to 2/3 concentration or with retinol palmitate solvent (castor oil) dissolved in blood plasma, showed immunoreactive fine granules without the occurrence of vacuoles in the cytoplasm. Identical vacuoles in serial sections appeared immunohistochemically either immunoreactive or non-immunoreactive for all the antibodies used, with rare exceptions. The occurrence of several rare exceptions suggested that 2 kinds of vacuoles might be formed in different cytoplasmic compartments. A zonal distribution of vacuoles was apparent in the hepatic laminae (or acini) within the liver lobules. The vacuoles were predominantly distributed in zone 2, and to a lesser extent in zone 3 and zone 1 in that order.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00261829
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    High resolution scanning electron-microscopic study on the three-dimensional structure of the sarcoplasmic reticulum in the slow (tonic) muscle fibers of the frog, Rana nigromaculata (1989)
    Springer
    Cell & tissue research 255 (1989), S. 669-672 
    Details
    ISSN: 1432-0878
    Keywords: Muscle, striated, skeletal ; Slow muscle fibers ; Muscle cells ; Sarcoplasmic reticulum ; Scanning electron microscopy ; Rana n. nigromaculata (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The three-dimensional structure of the sarcoplasmic reticulum (SR) in the slow (tonic) fibers of the reclus abdominis muscle of the Japanese meadow frog (Rana nigromaculata nigromaculata Hallowell) was examined by high resolution scanning electron microscopy, after removal of the cytoplasmic matrices by the osmium-DMSO-osmium procedure. The SR forms a repetitive network throughout these fibers. At the level of the Z-line, a slender transverse tubule (T-tubule) runs transversely to the longitudinal axis of the myofibril. Small, spherical or ovoid terminal cisternae couple laterally with the T-tubule at intervals of 0.4–1.0 μm, and form a “terminal cisterna-T-tubule complex” on whose surface tiny indentations are occasionally seen. Each terminal cisterna gives rise to a few sarcotubules that run in various directions, divide frequently and form circular or oval meshes of diverse sizes in front of the A- and I-bands. The sarcotubules usually form small meshes in the middle of the A-band, but occasionally fuse and form a poorly developed H-band (fenestrated) collar.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218807
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Corrosion casts as a method for investigation of the insect tracheal system (1989)
    Springer
    Cell & tissue research 256 (1989), S. 1-6 
    Details
    ISSN: 1432-0878
    Keywords: Corrosion casts ; Tracheal system ; Respiration ; Scanning electron microscopy ; Insecta ; Cataglyphis bicolor, Apis mellifera, Musca domestica (Insecta) Tracheal system, insects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The tracheal systems of five insect species (two species of ants, worker bee, housefly and the cabbage butterfly) have been studied by scanning electron microscopy of corrosion casts. This technique, which is commonly used for the investigation of vertebrate vasculature, is adapted to demonstrate the ultrastructure of the insect respiratory organ. The problem of filling a “blind ending system” was solved by injecting the resin Mercox into the evacuated tracheae through a thoracal spiracle. After polymerization of the resin, the tissue was digested enzymatically and chemically. The three-dimensional structure of the tracheal system was investigated by scanning electron microscopy. The technique used here displays for the first time the complex morphology of the entire tracheal system in fine detail, especially the structure of spiracles, airsacs, tracheae and tracheoles. Smooth-walled terminal tracheoles show up in flight muscles. The finest tracheoles that could be identified have diameters of approximately 70 nm. This approaches the finest tracheoles portrayed by transmission electron micrographs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224712
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Lateral diffusion of proteins and lipids in the plasma membrane of rose protoplast (1989)
    Springer
    Protoplasma 152 (1989), S. 46-56 
    Details
    ISSN: 1615-6102
    Keywords: Calcium ; Fluorescence photobleaching recovery ; Lateral diffusion ; Lipid phase ; Plasma membrane ; Protoplast regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Lateral diffusion measurements have been made on lipids and proteins in the plasma membrane of live protoplasts derived from rose (Rosa sp. “Paul's Scarlet”) suspension-cultured cells. Two different fluorescent lipid probes exhibited markedly different diffusion rates, indicating possible heterogeneity in the lipid domain of the membrane. Membrane proteins were labeled directly with covalently-reactive fluorophores, and factors that might perturb the lateral diffusion of these labeled proteins were investigated. Treatment of the protoplasts with various cytoskeleton-disrupting drugs generally had little effect on protein diffusion, although treatment with oryzalin, a microtubule-disrupting drug, did slightly reduce the mobile fraction of membrane proteins. Elevation of the CaCl2 concentration in the medium from 1 mM to 10 mM significantly reduced the mobile fraction of membrane proteins and also increased the fraction of protoplasts that were able to regenerate cell walls and divide in culture. These results are discussed in relation to reported evidence of lipid domains in the plasma membranes of other cells and protoplasts. The relative importance of lipid domains and membrane-cytoskeleton interaction in governing protein diffusion is considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01354239
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    The prestalk/prespore differentiation and polarized cell movement inDictyostelium discoideum slugs. A possible involvement of the intracellular Ca2+-concentration (1989)
    Springer
    Protoplasma 151 (1989), S. 175-178 
    Details
    ISSN: 1615-6102
    Keywords: Dictyostelium discoideum ; Cellular slime moulds ; Calcium ; Cyclic AMP ; Chemotaxis ; Differentiation ; Slug movement
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Intracellular free calcium ion concentrations ([Ca2+]i) in the anterior prestalk and posterior prespore cells of theDictyostelium discoideum slug were determined, using the highly selective Ca2+ indicators, quin-2/AM and fura-2/AM. Temporal changes in [Ca2+]i in response to chemotactic stimulation with cAMP were also monitored at the single-cell level and compared between the two types of cells. The results obtained showed that resting [Ca2+]i in the prestalk cells is considerably higher than that in the prespore cells. Moreover, transient increase in [Ca2+]i upon stimulation with a low concentration of cAMP (20 nM) was noticed only in the prestalk cells, but not in the prespore cells. These facts are discussed in relation to the polarized movement and cellular differentiation in the migrating slug.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01403457
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Characterising adhesiveness ofPhytophthora cinnamomi zoospores during encystment (1989)
    Springer
    Protoplasma 149 (1989), S. 24-30 
    Details
    ISSN: 1615-6102
    Keywords: Adhesion ; Calcium ; Lectins ; Phytophthora cinnamomi ; Secretion ; Zoospore
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary During encystment,Phytophthora cinnamomi zoospores bind firmly to the host surface. We have developed a microassay to study adhesion of the zoospores to solid surfaces, both biological and non-biological. The results show that timing of the acquisition of adhesiveness during encystment correlates closely with the secretion of high molecular weight glycoproteins. The adhesive phase is short lived, occurring between 1 and 4 min after induction of encystment. During this period, cells that come into contact with a variety of surfaces (glass, plastic, and onion epidermis) become firmly attached, while cells that come into contact with one of these substrata after this period are unable to bind. Our results also show that EGTA inhibits cyst adhesion, while addition of calcium promotes cyst adhesion, especially of cysts more than 4 min old. To help identify the cyst surface component involved in adhesion we tested a number of lectins for their ability to block cyst adhesion. Soybean agglutinin andHelix pomatia agglutinin, lectins which bind to the secreted high molecular weight glycoproteins, both inhibit adhesion in the presence and absence of the hapten sugar, indicating that inhibition was non-specific. Wheatgerm agglutinin, a lectin which does not bind to the cyst surface, also blocked adhesion non-specifically.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01623979
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Pollen-pistil interactions inBrassica oleracea: Cell calcium in self and cross pollen grains (1989)
    Springer
    Protoplasma 151 (1989), S. 57-61 
    Details
    ISSN: 1615-6102
    Keywords: Brassica ; Self-incompatibility ; Pollen ; Chlorotetracyline ; Energy-dispersive X-ray analysis ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The levels of calcium in pollen grains on the stigma, after self vs. cross pollinations, were compared inBrassica oleracea, a species showing sporophytic self-incompatibility. Self pollen was characterized by higher levels of chlorotetracycline fluorescence and by higher calcium signals in energy-dispersive analysis of X-rays than cross pollen. Cellular integrity of pollen grains was maintained after rejection, and self pollen could be rescued from the stigma to germinate 4 h after pollination, suggesting that the rejection response was not irreversible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01403301
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Rise in chlorotetracycline fluorescence accompanies tracheary element differentiation in suspension cultures ofZinnia (1989)
    Springer
    Protoplasma 152 (1989), S. 37-45 
    Details
    ISSN: 1615-6102
    Keywords: Calcium ; Chlorotetracycline ; Endoplasmic reticulum ; Tracheary element ; Xylogenesis ; Zinnia elegans
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Developing tracheary elements in suspension cultures ofZinnia elegans fluoresce intensely relative to non-differentiating cells when stained with chlorotetracycline (CTC), a fluorescent chelate probe for membrane associated calcium. This suggests that a change in calcium uptake or subcellular distribution accompanies the onset of tracheary element differentiation. A few cells in early differentiating cultures were brightly fluorescent, but did not have visible cell wall thickenings, suggesting that a rise in sequestered calcium may precede visible differentiation. Diffuse CTC fluorescence in early differentiation most likely results from sequestration of calcium in the endoplasmic reticulum. Late in differentiation, CTC fluorescence becomes punctate in appearance, probably due to loss of plasma membrane integrity occurring at the onset of autolysis.Zinnia suspension culture cells were found to be very sensitive to CTC and low concentrations (10 μM) were used to assure accurate localization of membrane-associated calcium in healthy cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01354238
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Plasma membrane proteins associated with undifferentiated and embryonicDaucus carota tissue (1989)
    Springer
    Protoplasma 150 (1989), S. 139-149 
    Details
    ISSN: 1615-6102
    Keywords: Biotinylation ; Daucus carota ; Development ; Embryogenesis ; Plasma membrane, SDS-PAGE
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Membranes and membrane proteins from undifferentiated cells and torpedo-stage embryos were compared. A comparison of marker enzyme profiles on linear sucrose gradients showed that the membrane vesicles obtained from 14-day-old embryos were consistently less dense than those obtained from undifferentiated carrot cells. The density of the endoplasmic reticulum, for instance, was 1.10g/cm3 in embryos and 1.12g/cm2 in undifferentiated cells. Proteins and glycoproteins from endoplasmic reticulum-, Golgi apparatus-, and plasma membrane-enriched fractions were compared from undifferentiated carrot cells with 14-day-old embryos by 2D SDS-PAGE. When these two tissues were compared, extensive qualitative and quantitative changes in the steady-state endomembrane and plasma membrane proteins were observed. The plasma membrane was examined further by labeling the plasma membrane proteins with sulfosuccinimidylbiotin. Using this specific label, plasma membrane proteins of 54 kD, 41 kD, 16 kD, and 15 kD were found to be uniquely associated with the embryonic state. Conversely, a 70 kD protein and a 45 kD glycoprotein were found to be associated with only undifferentiated cells. These results demonstrate that proteins of the plasma membrane exhibit distinct changes as a result of somatic embryogenesis in carrot.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01403670
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Distribution of membrane-bound calcium and activated calmodulin during somatic embryogenesis of carrot (Daucus carota L.) (1989)
    Springer
    Protoplasma 153 (1989), S. 24-29 
    Details
    ISSN: 1615-6102
    Keywords: Calcium ; Calmodulin ; Chlorotetracycline ; Daucus carota ; Fluphenazine ; Somatic embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The distribution of membrane-bound calcium and activated calmodulin was visualized during carrot somatic embryogenesis by chlorotetracycline (CTC) and fluphenazine fluorescence respectively. Somatic embryos of all stages possessed a higher CTC fluorescence in comparison with the signal from their precursors, the proembryogenic masses. The CTC fluorescence was evenly distributed in the somatic embryos. In contrast, fluphenazine was observed in some regions of the proembryogenic masses only. In the globular, heart-shaped and early torpedo-shaped stage its fluorescence was restricted to the basal part of the embryo. In the older torpedo-shaped embryos also the shoot apex showed fluphenazine fluorescence. It is concluded that during carrot somatic embryogenesis a polarity in the distribution of the activated calmodulin already exists before this polarity is morphologically expressed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01322461
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Calcium oxalate formation is a rapid and reversible process inLemna minor L. (1989)
    Springer
    Protoplasma 148 (1989), S. 130-137 
    Details
    ISSN: 1615-6102
    Keywords: Calcium ; Calcium oxalate ; Crystals ; Lemna minor ; Roots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Lemna minor root tips form raphide Ca oxalate crystals in both the root cap and root proper. An in vivo system was developed to examine raphide crystal bundle formation in the root of intact plants. By increasing the exogenous Ca concentration, crystal bundle formation could be induced. Entire new crystal bundles could be formed within 30 minutes of an inductive stimulus. The process was reversible with recently formed crystal bundles being dissolved over a period of about 3 hours. Older, previously existing bundles were more resistant to dissolution. The calmodulin antagonists, chlorpromazine and trifluoperazine (300 μM), prevented crystal formation and caused dissolution of some crystal bundles, even in the presence of exogenous Ca. When the antagonists were flushed out and replaced with fresh medium, crystals were formed in cells where dissolution had occurred under the influence of the antagonists. The Ca ionophore A 23187 (20 μM) caused slow dissolution of crystal bundles, even in the presence of exogenous Ca. A model describing the control of and physiological significance of Ca oxalate formation in plants is presented and discussed with respect to the results obtained in this study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02079332
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Cyclic development of contact behavior in apes and humans (1989)
    Springer
    Primates 30 (1989), S. 269-279 
    Details
    ISSN: 0032-8332
    Keywords: Development ; Gorillas ; Orangutans ; Chimpanzees ; Apes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Nursing and mother-infant distance were observed in three orangutans, two gorillas, one chimpanzee and four humans. All four species showed periods of a recurrence of greater time spent nursing and in contact with the mother. The initial regressive or reattachment period occurred similarly in all four species at between 6–12 months of age. An orangutan observed for two years showed a second period at 19–21 months. Other studies of weight gain in the three ape species coincidently peaked at the same time. When estimated peaks of individuals of each species were summed, the resulting graphs showed a differentiation of species rates of development. Gorillas developed most rapidly, orangutans developed most slowly, while chimpanzees and humans developed within the middle range.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02381314
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    A longitudinal investigation of gestural communication in young chimpanzees (1989)
    Springer
    Primates 30 (1989), S. 35-50 
    Details
    ISSN: 0032-8332
    Keywords: Chimpanzees ; Communication ; Development ; Social learning ; Culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A longitudinal study of chimpanzee gestural communication is reported. Subjects were seven 5- to 8-year-old members of a semi-natural group at the Yerkes Field Station. These were the same individuals observed byTomasello et al. (1985) four years previously. Nearly identical operational definitions and observational procedures were used in the two studies. Longitudinal comparisons between the two observation periods revealed that the development of chimpanzee gestural communication is best characterized as a series of ontogenetic adaptations: as particular social functions (e.g., nursing, playing, grooming, etc.) arise, decline, or change, gestural communication follows suit. Most gestures seem to be conventionalized by individuals in direct social interaction with conspecifics. Some gestures may be learned by “second-person imitation”—an individual copying a behavior directed to it by another individual. No evidence was found for “third-person imitation”—an individual copying a gesture used between two other individuals. Implications for the concept of chimpanzee “culture” are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02381209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Theamylase gene-enzyme system of fishes (1989)
    Springer
    Journal of comparative physiology 159 (1989), S. 237-242 
    Details
    ISSN: 1432-136X
    Keywords: Amylase ; Mosquitofish ; Rat ; Drosophila ; Structure ; Function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Amylases from the mosquitofish (Gambusia affinis holbrooki, Pisces: Poeciliidae) and rat were purified and compared withDrosophila amylases in terms of structure and function. At the structural level, amino acid compositions of the three amylases were compared. At the functional level, amylase activities were compared on various substrates and in the presence of inhibitors. While the amylases from all three organisms had properties typical of alpha-amylases, both structural and functional differences were observed. Using resemblance coefficients of distance and similarity from numerical taxonomy, it was determined that the amylases from the rat andDrosophila were more similar to each other than either was to amylase from the mosquitofish, and that structural differences between the amylases did not reflect functional differences, i.e. there was no correlation between amylase structural and functional distances.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00691744
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Endogenous 24-hour cycle of core temperature and oxygen consumption in week-old Zucker rat pups (1989)
    Springer
    Journal of comparative physiology 159 (1989), S. 569-575 
    Details
    ISSN: 1432-136X
    Keywords: Artificial rearing ; Circadian ; Development ; Newborn ; Thermoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Experiments were designed to test whether or not the 24-h core temperature fluctuations in week-old rat pups are of endogenous origin. Lean (Fa/-) Zucker rat pups born on the same day to mothers maintained in two different colonies with light/dark cycles 12 h out of phase with each other were mother-reared through the first 3–4 days of life and then artificially reared simultaneously in constant dim light. Continuous, automatic measurement of core temperature and oxygen consumption during artificial rearing showed clear 24-h rhythms in 5- to 8-day-old pups. Each rhythm reached a daily minimum at a time corresponding to the beginning of the light period in the colony of origin. The amplitude of these rhythms did not diminish during artificial rearing, nor did the phase difference between the rhythms of pups originating in the two colonies systematically change. The persistent 12-h phase differences between these two groups of pups prove that the observed rhythms are not caused by exogenous stimuli. We conclude that the rat pup possesses an endogenous time-keeping mechanism that permits the expression of overt rhythmicity at the age of 1 week.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00694381
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Environmental modulation of calcium and phosphorus metabolism in embryonic snapping turtles (Chelydra serpentina) (1989)
    Springer
    Journal of comparative physiology 159 (1989), S. 501-508 
    Details
    ISSN: 1432-136X
    Keywords: Calcium ; Embryos ; Phosphorus ; Turtles ; Water
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Eggs of common snapping turtles (Chelydra serpentina) were incubated on wet (−150 kPa water potential) and dry (−950 kPa) substrates in a laboratory study assessing the effects of the hydric environment on patterns of mobilization of calcium and phosphorus by developing embryos. We found that embryos developing in wet environments withdrew nutrients from their yolk faster, grew more rapidly, and incubated longer than embryos exposed to dry environments. Turtles developing in both environments absorbed calcium from the yolk at similar rates and depleted the yolk of almost its entire reserve of calcium prior to hatching. Calcium withdrawn from the yolk was supplemented with calcium mobilized from the eggshell, but embryos in wet environments obtained substantially more calcium from the eggshell than did those in dry settings. Embryos obtained all of the phosphorus used in skeletogenesis from the yolk, but those incubating in wet environments mobilized phosphorus from this compartment more rapidly than did those in dry settings. Exposing embryonic snapping turtles to wet environments apparently allows them to make more efficient use of the transitory source of calcium in the eggshell than is possible in dry environments. However, the residual yolk in hatchlings from both wet and dry environments contains too little calcium to support the growth of hard and soft tissues in neonates at rates similar to those characterizing the growth phase of development in embryogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00692422
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Bone tissue formation in human bone marrow organ cultures (1989)
    Springer
    Bulletin of experimental biology and medicine 107 (1989), S. 684-686 
    Details
    ISSN: 1573-8221
    Keywords: bone marrow ; man ; organ cultures ; osteogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00841786
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Tetramethylammonium-calcium-triazid. Darstellung und Kristallstruktur (1988)
    Springer
    Monatshefte für Chemie 119 (1988), S. 1245-1249 
    Details
    ISSN: 1434-4475
    Keywords: Azide ; Calcium ; Crystal structure ; Tetramethylammonium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract [N(CH3)4]Ca(N3)3,M=240.29, was prepared from aqueous solutions of tetramethylammoniumazide with calciumazide at 298 K. The crystals are tetragonala=936.6(7) pm,c=694.7(5)pm, space group P4/nmm,Z=2, ρ(x)=1.31Mgm−3. The crystal structure was determined by single crystal x-ray diffraction (234 Mo-Kα-reflections, μ=0.469 mm−1,R=0.064). Calcium is octahedrally coordinated to six azide groups. The octahedra are connected via azide groups to a threedimensional array with the complex ammonium ions between. The terminal nitrogen atoms of the azide groups and the methyl groups are considerably disordered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00808305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Die Kristallstruktur des Calciumazid-Dihydrates (1988)
    Springer
    Monatshefte für Chemie 119 (1988), S. 921-927 
    Details
    ISSN: 1434-4475
    Keywords: Azide ; Calcium ; Crystal structure ; Dihydrate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Single crystals of Ca(N3)2·2 H2O have been prepared from aqueous solutions at room temperature. The crystals are monoclinic,a=1 159.0 (3),b=614.2 (2),c=785.5 (2) pm, β=106.52 (2)°,Z=4, space group P21/n. The crystal structure was determined by single crystal X-ray diffraction (1 109 Mo-Kα-reflexions,R=0.052). Calcium atoms are surrounded by four azide groups and four water molecules. The coordination polyhedra are antiprism which are sharing azide groups and water molecules to form layers. The lattice constants and powder pattern agree well with values reported earlier for Ca(N3)2 · 1.5 H2O [1]. It was also shown, that Sr(N3)2 · 2 H2O is isotypic with Ca(N3)2 · 2 H2O.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Immunological homologies between yeast ribosomal protein L2 and rat liver ribosomal proteins L4 and L24 (1988)
    Springer
    Current genetics 13 (1988), S. 235-239 
    Details
    ISSN: 1432-0983
    Keywords: Ribosomal protein ; Immunological homology ; Yeast ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Polyclonal antibodies raised against ribosomal protein (r-protein) L2 of Schizosaccharomyces pombe were used to check for cross-reaktions with total r-proteins of rat liver. Using this procedure, the rat liver r-proteins, L4 and L24, were identified as being immunologically related to yeast L2. In addtional, homologies between rat liver L4 and L24 were detected. The possible implications for the regulation of r-protein synthesis are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387769
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Transport processes in stimulated and non-stimulated leaves of Mimosa pudica (1988)
    Springer
    Trees 2 (1988), S. 65-72 
    Details
    ISSN: 1432-2285
    Keywords: Calcium ; Chlorine ; Ion shifts ; Mimosa pudica ; Potassium ; Seismonastic movements ; X-ray microanalysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Using energy-dispersive X-ray microanalysis, the concentrations of ions, especially potassium and chlorine, were determined in different tissues of primary and tertiary pulvini of Mimosa pudica. It was shown that stimulating the leaf was followed by ion displacements which were most striking in the outer extensor cells, resulting in turgor loss. Since Ca concentration remains relatively constant in cell walls of collapsed cells, the changes of K concentration are best described by the K:Ca ratio. After stimulation the K:Ca ratio dropped in the outer extensor of the primary pulvinus from 775.3 to 2.37 in the cytoplasm, and from 542.2 to 9.25 in the cell wall. Changes in chlorine content were less striking in the primary pulvinus. The K∶Cl ratios in some cases were lower than 1.0, which indicates that Cl content can increase, while K content is diminished. In the non-stimulated tertiary pulvini the outer extensor cells show high concentrations of Cl, but much lower Cl concentrations were found after stimulation. In contrast to the primary pulvinus the K content of the tertiary pulvini is very low. In the vascular tissues of both primary and tertiary pulvini stimulation is followed by a release of K and Cl out of the sieve element cytoplasm into the apoplast. K then appears accumulated in the cell walls of the collenchymatous tissue. These displacements lead to the assumption that the collenchymatous apoplast temporarily functions as a reservoir for K and to a lesser extent for Cl. With regard to the mechanism of leaf movement after stimulation, the accumulation of ions in the apoplast seems to be initiated by the decrease of water potential triggered by an apoplastic accumulation of unloaded sucrose (Fromm and Eschrich 1988a). The resulting turgor release in the outer extensor is accompanied by an efflux of ions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00196751
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Microbeam analysis of Ca exchange and uptake in the fine roots of spruce: influence of pH and aluminum (1988)
    Springer
    Trees 2 (1988), S. 96-103 
    Details
    ISSN: 1432-2285
    Keywords: Aluminum ; Calcium ; Fine roots ; Microbeam analysis ; Picea abies ; Soil acidification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary A novel stable isotope labelling procedure for microbeam analysis was developed to monitor exchange and uptake of nutrients, primarily Mg, K and Ca, by root tips at the cellular level. Initially root samples were analysed from 2-year-old spruce trees, originating both from a nursery and from a polluted forest site, (1) for the cortex cell wall accessibility and nutrient binding properties, (2) for the influence of low pH and elevated aluminum concentrations on Ca binding to cortex cell walls, and (3) for long-range transport into the secondary xylem, proximal to the labelled root tip. In nursery control plants, Ca is localized mainly in the apoplast of the cortex. Exchange of Mg, K, Ca in the cell wall of the cortex and the primary xylem with label in incubation solutions is almost completed to equilibration within 30 min. In the secondary xylem we could detect Mg, K, and Ca from labelling solutions in minute amounts after 30 min, and as a major fraction after 48 h. This indicates that stable isotope labelling can be used to study both ion-exchange properties of the apoplast and long-range transport. Slight acidification of the labelling incubation media to pH 4.5 reduced Ca binding to the cortex cell walls slightly, but acidification to the extreme value of pH 2.3 reduced binding 41%. A combination of pH 4.5 and increased free aluminum reduced the binding by 83%. In a preliminary attempt to analyse the nutrient binding capability of the root-tip apoplast from pollution affected trees, we exposed fine roots of 2-year-old spruce from an acidified and polluted site showing typical low levels of Ca and Mg in the cortical cell walls to Ca-enriched media. Under these conditions the Ca content of cortex cell walls doubled upon incubation at pH 4.7, reaching 40% of the total binding capacity of our nursey control plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00196755
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Monoamine oxidase activity in single nerve cell bodies from substantia nigra of rat and man (1988)
    Springer
    Cellular and molecular life sciences 44 (1988), S. 710-712 
    Details
    ISSN: 1420-9071
    Keywords: MAO A ; MAO B ; substantia nigra ; rat ; man ; MPTP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In single nerve cell bodies isolated from the substantia nigra of man and rat the active forms of MAO A and MAO B were found by the use of the microdiver technique and specific inhibitors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01941038
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    The reinforcement-extinction process of selector gene activity: a positive feed-back loop and cell-cell interactions in Ultrabithorax patterning (1988)
    Springer
    Development genes and evolution 197 (1988), S. 424-434 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Ultrabithorax ; Development ; Regulation ; Protein distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Most viable alleles of homeotic genes cause partial transformations within given lineages in a topographically specific fashion. We study this phenomenon as a way to understand the normal mechanisms involved in the spatial regulation of homeotic gene expression. To this end we have investigated the distribution of Ultrabithorax (Ubx) proteins in imaginai discs mutant for hypomorphic and neomorphic alleles of Ubx and alleles of trans-acting genes. We find that the morphological discontinuities observed in the adult transformations are caused by corresponding new patterns of the Ubx proteins in the imaginai anlagen. These novel patterns of Ubx proteins are understood as a consequence of a process of reinforcement-extinction of Ubx expression. The evidence suggesting that this process results from a positive feed-back loop and cell-cell interactions is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00398994
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Inhibition of muscarinic receptor-mediated Ca27#x002B; mobilization by phorbol 12-myristate 13-acetate in chick embryo cells (1988)
    Springer
    Development genes and evolution 197 (1988), S. 37-39 
    Details
    ISSN: 1432-041X
    Keywords: Phorbol ester ; Muscarinic receptor ; Calcium ; Chick embryo ; Morphogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A muscarinic cholinergic receptor is present on undifferentiated cells of the chick embryo. Stimulation of the muscarinic receptor with muscarinic agonists triggers intracellular Ca2#x002B; mobilization. Here, we investigate the effect of phorbol 12-myristate 13-acetate (PMA) on the muscarinic receptor-mediated Ca2#x002B; mobilization, which is monitored in cell suspensions of chick embryos of stage 24 by chlorotetracycline fluorescence. PMA inhibits the Ca2#x002B; mobilization in a time-dependent and concentration-dependent manner without changing the ED50 of acetylcholine. The concentration of PMA that gives halfmaximal inhibition is 3.1×10−9 M PMA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00376039
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Cytosolic calcium in platelet activation (1988)
    Springer
    Cellular and molecular life sciences 44 (1988), S. 97-100 
    Details
    ISSN: 1420-9071
    Keywords: Calcium ; platelet ; second messenger
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Experiments with permeabilised platelets, and with intact platelets loaded with fluorescent Ca2+-indicators, over the past several years have greatly extended our knowledge and understanding of cytosolic Ca2+ as a platelet activator and its interactions with other cytosolic regulators. This article outlines insights, gained from the use of the fluorescent dyes, into maintenance and restoration of basal [Ca2+]i, mechanisms of receptor-mediated Ca2+-mobilisation and quantitation of [Ca2+]i/response relations in intact human platelets.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01952188
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Epilepsy and electromagnetic fields: effects of simulated atmospherics and 100-Hz magnetic fields on audiogenic seizure in rats (1988)
    Springer
    International journal of biometeorology 32 (1988), S. 17-20 
    Details
    ISSN: 1432-1254
    Keywords: Epilepsy ; Electromagnetic fields ; Rat ; Audiogenic seizure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract In order to study the possible association between epileptic seizures and natural electromagnetic fields, 32 female audiogenic seizure (AGS)-susceptible rats were exposed to simulated 10 kHz and 28 kHz atmospherics and to a sinusoidally oscillating magnetic field with a frequency of 100 Hz and field strength of 1 A/m. After the electromagnetic exposure, seizures were induced in the rats with a sound stimulus. The severity of the seizure was determined on an ordinal scale, the audiogenic response score (ARS). The time from the beginning of the sound stimulus to the onset of the seizure (seizure latency) and the duration of the convulsion was measured. No differences from the control experiments were found in the experiments with simulated atmospherics, but the 100 Hz magnetic field increased the seizure latency by about 13% (P〈0.02). The results do not support the hypothesis that natural atmospheric electromagnetic signals could affect the onset of epileptic seizures, but they suggest that AGS-susceptible rats may be a useful model for studying the biological effects of electromagnetic fields.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01623987
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Demonstration of correlations between the 8 and 10 kHz atmospherics and the inflammatory reaction of rats after carrageenan injection (1988)
    Springer
    International journal of biometeorology 32 (1988), S. 201-204 
    Details
    ISSN: 1432-1254
    Keywords: Atmospherics ; Carrageenan inflammation ; Rat ; Susceptibility ; Correlations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract Between the mean daily density of 28 kHz atmospherics and the onset of epileptic fits there is a highly significant correlation coefficient (r) of 0.30; there is a negative coefficient of −0.20 between the fits and the mean daily density of 10 kHz atmospherics. The onset of heart infarction is correlated with 28 kHz atmospherics (r=0.15). Furthermore, we have discovered that sudden deafness is also correlated with certain configurations of atmospherics. In this paper we report the following correlation coefficients between the inflammatory reaction of rats to a carrageenan injection (rci) into a hind paw and the mean daily pulse rate of atmospherics of the same day:r=0.49 for the 8 kHz atmospherics (P〈0.02) andr=0.44 for the 10 kHz atmospherics (P〈0.04). The correlations between rci reaction and other atmospherics (12 and 28 kHz) are smaller and not significant. By the method of multiple linear regression we found a multipleR=0.54 between rci reaction and the 8 and 10 kHz atmospherics (the regression function for the rci reaction is 0.15+0.004×8 kHz+0.002×10 kHz,P〈0.05).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01045280
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Calcium-dependent protein kinase from apple fruit membranes is calmodulin-independent but has calmodulin-like properties (1988)
    Springer
    Planta 176 (1988), S. 91-97 
    Details
    ISSN: 1432-2048
    Keywords: Calcium ; Calmodulin ; Malus (protein kinase) ; Protein kinase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Crude Ca2+-activated protein kinase from membranes of apple (Malus domestica L. Borkh., Cox's Orange Pippin) fruit can be partially purified to yield a Ca2+-dependent protein kinase whose activity is apparently not regulated by calmodulin. The autophosphorylating catalytic subunit of this protein kinase shows a Ca2+-dependent mobility shift of approx. 10 kilodaltons (kDa) on sodium dodecyl sulphate-polyacrylamide gel electrophoresis; in the absence of added Ca2+ or ethylene glycol-bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid (EGTA) its apparent molecular mass is approx. 50 kDa. The Ca2+-dependent protein kinase is inhibited by the calmodulin antagonists N-(6-aminohexyl)-5-chloro-1-naphthalenesulphonamide and trifluoperazine with IC50 values of approx. 45 μM and 15 μM, respectively. These similarities between the protein kinase and calmodulin indicate that the kinase may be a calmodulin-like protein.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00392484
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    The relationship among egg size, density and food level on larval development in the wood frog (Rana sylvatica) (1988)
    Springer
    Oecologia 75 (1988), S. 67-72 
    Details
    ISSN: 1432-1939
    Keywords: Rana sylvatica ; Egg size ; Development ; Density ; Food level
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Although inter- and intraspecific variation in egg size among amphibians has been well documented, the relationship between egg size and fitness remains unclear. Recent attempts to correlate egg size intraspecifically with larval developmental patterns have been equivocal. In this study the development of larvae derived from large eggs and small eggs, from a single population in Maryland were compared under a range of food levels and larval population densities. Both food level and density had significant effects on the length of the larval period and size at metamorphosis. However, the response among larvae derived from different egg sizes was not additive. At low densities and high food levels, larvae from small eggs had longer larval periods and a larger size at metamorphosis than larvae derived from large eggs. In contrast, at high densities larvae from small eggs had longer developmental periods but were smaller at metamorphosis than larvae from large eggs. In addition, larvae from small eggs were more sensitive to density irrespective of food level. These results suggest that optimal egg size is correlated with environmental factors, which may explain the maintenance of both geographic and within population variation in egg size commonly observed in amphibians.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00378815
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Isolated generative cells in some angiosperms: a further study (1988)
    Springer
    Sexual plant reproduction 1 (1988), S. 97-102 
    Details
    ISSN: 1432-2145
    Keywords: Generative cell ; Isolation ; Scanning electron microscopy ; Immunofluorescence ; Video-enhanced microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Generative cells were isolated from the pollen grains of three angiosperm species by a method similar to that previously reported for Haemanthus katherinae (Baker). Both the external appearance and the internal structure of the isolated generative cells were observed by light and scanning electron microscopy. The dynamic changes occurring in the cells after they had been liberated from the pollen grains were recorded by video-enhanced microscopy. The distribution of microtubules in the isolated cells was revealed by immunofluorescence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00189268
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Calcium control of differentiation in Phytophthora palmivora (1988)
    Springer
    Archives of microbiology 149 (1988), S. 565-571 
    Details
    ISSN: 1432-072X
    Keywords: Phytophthora ; Zoospores ; Calcium ; Encystment ; Differentiation ; Pectin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A method has been developed for the preparation of zoospores from Phytophthora palmivora which allows the ionic composition of the suspension medium to be closely controlled. Sub-micromolar concentrations of calcium ions have been shown to play a key role in maintaining the zoospore state and in the transition to the cyst stage. Restriction of free Ca2+ to between 0.2 and 1 μM resulted in zoospores which could be maintained for several hours before they finally encysted and germinated. When exposed to citrus-pectin, or 3 mM SrCl2, or to vigorous shaking, these zoospores underwent rapid synchronous encystment. At free Ca2+ concentrations below 0.1 μM, zoospores lysed slowly. If exposed to inducers of encystment before lysis had occurred, the zoospores failed to respond to pectin or to vigorous shaking. However, they did differentiate in response to SrCl2 addition. Provided the free Ca2+ was maintained between 0.02 and 0.2 μM, zoospores survived gentle centrifugation, a procedure which previously had resulted in encystment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446762
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Specific binding of the calcium channel blocker [3H]verapamil to membrane fractions of Chlamydomonas reinhardtii (1988)
    Springer
    Archives of microbiology 149 (1988), S. 451-458 
    Details
    ISSN: 1432-072X
    Keywords: Chlamydomonas reinhardtii ; Phototaxis ; Galvanotaxis ; Calcium ; Calcium channels ; Calcium channel blockers ; Radioligand binding ; Polymer twophase system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Specific binding of the calcium antagonist [3H]verapamil to a microsomal fraction, a presumptive plasma membrane fraction and an intracellular membrane fraction of the phototactic unicellular green alga Chlamydomonas reinhardtii has been demonstrated. The specific activity of the plasma membrane marker enzyme K+-stimulated, Mg2+-dependent ATPase was severalfold higher in the upper (polyethylene glycol-rich) than in the lower (dextran-rich) phase, and the reverse was established for the marker enzymes of intracellular membranes such as cytochrome c oxidase for mitochondria and antimycin Aresistant NADPH-cytochrome c reductase for endoplasmic reticulum. Chlorophyll as a marker for thylakoid fragments was exclusively found in the lower phase. In the microsomal fraction two specific binding sites of [3H]verapamil were found at 22°C, one with higher and a second with lower affinity to [3H]verapamil. Separation of plasma membranes from intracellular membranes revealed that the “highaffinity” binding site is attributed to the plasma membrane fraction whereas the “low-affinity” binding site can be attributed to the intracellular membrane fraction. Specific binding to both separated membrane fractions is saturable and reversible. [3H]Verapamil binding to plasma membranes was not inhibited by the calcium channel blockers diltiazem and nifedipine. However, in the intracellular membrane fraction [3H]verapamil could be displaced by diltiazem but not by nifedipine. Increasing concentrations of calcium chloride inhibited [3H]verapamil binding in both fractions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425587
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Glycerol-3-phosphatase and the control of glycerol metabolism in Dunaliella tertiolecta cells (1988)
    Springer
    Archives of microbiology 150 (1988), S. 109-112 
    Details
    ISSN: 1432-072X
    Keywords: Calcium ; Dunaliella tertiolecta ; Enzyme kinetics ; Glycerol ; Glycerol-3-phosphatase ; Metabolic regulation ; Osmoacclimation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Glycerol-3-phosphatase (EC 3.1.3.2.1) was studied by following the release of radioactive glycerol from L-(U-14C)glycerol-3-phosphate in Dunaliella tertiolecta enzyme extracts. The reaction showed a neutral pH optimum and had an absolute requirement for Mg2+. The substrate saturation curve was hyperbolic with an apparent K m value for glycerol-3-phosphate of 0.7 mM in the absence of phosphate. Inorganic orthophosphate was a competitive inhibitor of the enzyme with an estimated K j of 0.1 mM. The glycerol-3-phosphatase reaction was blocked nearly completely by millimolar Ca2+ concentrations. Ca2+ inhibition did not depend on the presence of calmodulin in the reaction medium. The characteristics of glycerol-3-phosphatase are discussed in relation to the regulation of the cyclic glycerol metabolism in Dunaliella cells during periods of osmotic stress.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425148
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Auxin causes oscillations of cytosolic free calcium and pH inZea mays coleoptiles (1988)
    Springer
    Planta 174 (1988), S. 495-499 
    Details
    ISSN: 1432-2048
    Keywords: Auxin, calcium and pH ; Calcium ; Cytosolic pH ; Membrane potential (double-barrelled micro-electrode) ; Zea (auxin, Ca2+, pH)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In epidermal cells of maize (Zea mays L.) coleoptiles, cytosolic pH (pHc), cytosolic free calcium, membrane potential and changes thereof were monitored continuously and simultaneously (pHc/,ψ m, Ca2+/ψ m) using double-barrelled ion-sensitive microelectrodes. In the resting cells the cytosolic pH was 7.3–7.5 and the concentration of free calcium was 119±24 nM. One-micromolar indole-3-acetic acid (IAA), added to the external medium at pH 6.0 triggered oscillations inψ m, pHc and free calcium with a period of 20 to 30 min. Acidification of the cytosolic pH increased the cytosolic free calcium. Theψ m oscillations are attributed to changes in activity of the H+-extrusion pump at the plasmalemma, triggered off by ΔpH and controlled by pH regulation (pH oscillation). The origin of the pHc and Ca2+ changes remains unclear, but is possibly caused by auxin-receptor-induced lipid breakdown and subsequent second-messenger formation. It is suggested that the observed cytosolic pH and Ca2+ changes are intrinsically interrelated, and it is concluded that this onset of regulatory processes through the phytohormone IAA is indicative of calcium and protons mediating early auxin action in maize coleoptiles. It is further concluded that the double-barrelled ion-sensitive microelectrode is an invaluable tool for investigating in-vivo hormone action in plant tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00634478
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Interendothelial junctions of cardiac capillaries in rats: their structure and permeability properties (1988)
    Springer
    Cell & tissue research 252 (1988), S. 57-66 
    Details
    ISSN: 1432-0878
    Keywords: Heart ; Endothelium ; Tracer studies ; Junctional structures ; Permeability ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The isolated perfused heart model was used to examine the structure of rat cardiac capillaries and their permeability to macromolecules of various sizes. Haemoglobin (diameter 6.4 nm) and catalase (10.4 nm) did not cross the endothelium but remained on the luminal side. Cytochrome C (3 nm) and horseradish peroxidase (6 nm) both crossed the endothelium to the subendothelial space and filled the caveolae on the abluminal side as well as the entire length of the lateral intercellular spaces. The membranes of the endothelial cells are separated by an intercellular gap of mean width 18.2 nm. At one or more zonular regions within each lateral intercellular space the two membranes approach each other more closely and frequently appear to fuse. However, tilting the specimen shows that, in these regions, there is a gap of mean width 5.4 nm (in lanthanum- and tannic acid-treated tissue, 3.8 nm in ferrocyanide-treated tissue) between the membranes. We conclude that these narrow regions sieve macromolecules on the basis of size although other factors may determine their permeability properties.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213826
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Lymphocyte number and distribution in the rat uterine epithelium during estrous cycle and early pregnancy (1988)
    Springer
    Cell & tissue research 253 (1988), S. 241-244 
    Details
    ISSN: 1432-0878
    Keywords: Uterus ; Intraepithelial lymphocytes ; Estrous cycle ; Early pregnancy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The number of intraepithelial lymphocytes (IEL) in the luminal and glandular epithelium of the uterus of virgin rats was analysed in diestrus, proestrus and estrus, and in nulliparous rats on days 5, 7 and 9 of pregnancy. IEL number was calculated either with respect to the number of epithelial cells or to the length of epithelium section. It was found that in diestrus, the number of IEL was, on average, 3.7 per 100 luminal epithelial cells or 6.7 per 1 mm of epithelium section, whereas in proestrus, it decreased to 0.9 and 1.2 IEL, respectively. On day 5 of pregnancy (before implantation) the number of IEL decreased further to 0.45 per 100 luminal epithelial cells or 0.9 per 1 mm of epithelium. On days 7 and 9 of pregnancy, IEL number further decreased in implantation sites, whereas in interimplantation sites it remained at the level calculated for day 5 of pregnancy. The population of uterine IEL consisted of small (82–99%) and large (1–18%) lymphocytes. In all stages of the estrous cycle, IEL occurred with a frequency of 68–87% in the basal region, 8–20% in the middle region and 4–12% in the apical region of the luminal epithelium width.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221759
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Cytoskeletons of retinal pigment epithelial cells: Interspecies differences of expression patterns indicate independence of cell function from the specific complement of cytoskeletal proteins (1988)
    Springer
    Cell & tissue research 254 (1988), S. 301-315 
    Details
    ISSN: 1432-0878
    Keywords: Retinal pigment epithelium ; Cytoskeleton ; Cytokeratins ; Vimentin ; Desmosomes ; Anura (Rana ridibunda, Xenopus laevis) ; Chicken ; Bovine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In vertebrate tissue development a given cell differentiation pathway is usually associated with a pattern of expression of a specific set of cytoskeletal proteins, including different intermediate filament (IF) and junctional proteins, which is identical in diverse species. The retinal pigment epithelium (RPE) is a layer of polar cells that have very similar morphological features and practically identical functions in different vertebrate species. However, in biochemical and immunolocalization studies of the cytoskeletal proteins of these cells we have noted remarkable interspecies differences. While chicken RPE cells contain only IFs of the vimentin type and do not possess desmosomes and desmosomal proteins RPE cells of diverse amphibian (Rana ridibunda, Xenopus laevis) and mammalian (rat, guinea pig, rabbit, cow, human) species express cytokeratins 8 and 18 either as their sole IF proteins, or together with vimentin IFs as in guinea pig and a certain subpopulation of bovine RPE cells. Plakoglobin, a plaque protein common to desmosomes and the zonula adhaerens exists in RPE cells of all species, whereas desmoplakin and desmoglein have been identified only in RPE desmosomes of frogs and cows, including bovine RPE cell cultures in which cytokeratins have disappeared and vimentin IFs are the only IFs present. These challenging findings show that neither cytokeratin IFs nor desmosomes are necessary for the establishment and function of a polar epithelial cell layer and that the same basic cellular architecture can be achieved by different programs of expression of cytoskeletal proteins. The differences in the composition of the RPE cytoskeleton further indicate that, at least in this tissue, a specific program of expression of IF and desmosomal proteins is not related to the functions of the RPE cell, which are very similar in the various species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225803
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Protein and collagen content of rat skeletal muscle following space flight (1988)
    Springer
    Cell & tissue research 254 (1988), S. 251-253 
    Details
    ISSN: 1432-0878
    Keywords: Space flight ; Skeletal muscle ; Collagen ; Protein ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Biochemical determinations of non-collagenous protein and hydroxyproline were made on rat skeletal muscles following 7 days of space flight aboard the NASA space shuttle mission SL-3. Relative to ground-based controls, the wet weight of each experimental muscle was significantly reduced. This was concomitant with a reduction in noncollagenous protein in the muscles. Protein concentration, however, was reduced only in slow-twitch muscles. The effect of space flight on the concentration and hydroxyproline content was different among the muscles. As a result, the loss of muscle mass in some muscles was the consequence of a reduction in both collagenous and non-collagenous proteins, while in others it was primarily the result of a non-collagenous protein loss.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220042
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Pinealocytes immunoreactive with antisera against secretory glycoproteins of the subcommissural organ: A comparative study (1988)
    Springer
    Cell & tissue research 254 (1988), S. 469-480 
    Details
    ISSN: 1432-0878
    Keywords: Pineal complex ; Pinealocytes, receptor line ; Subcommissural organ ; Immunocytochemistry ; Protein secretion ; Neuroendocrine system Geotria australis (Cyclostomata) ; Onkorhynchus kisutch (Teleostei) ; Eupsophus roseus (Anura) ; Heloderma suspectum, Varanus monitor (Lacertilia) ; Domestic fowl ; Rat ; Bovine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary By means of light-microscopic immunocyto-chemistry two polyclonal antibodies (AFRU, ASO; see p. 470) directed against secretory glycoproteins of the subcom-missural organ were shown to cross-react with cells in the pineal organ of lamprey larvae, coho salmon, a toad, two species of lizards, domestic fowl, albino rat and bovine (taxonomic details, see below). The AFRU-immunoreactive cells were identified as pinealocytes of the receptor line (pineal photoreceptors, modified photoreceptors or classical pinealocytes, respectively) either due to their characteristic structural features or by combining AFRU-immunoreaction with S-antigen and opsin immunocytochemistry in the same or adjacent sections. Depending on the species, AFRU- or ASO-immunoreactions were found in the entire perikaryon, inner segments, perinuclear area, and in basal processes facing capillaries or the basal lamina. In most cases, only certain populations of pinealocytes were immunolabeled; these cells were arranged in a peculiar topographical pattern. In lamprey larvae, immunoreactive pinealocytes were observed only in the pineal organ, but not in the parapineal organ. In coho salmon, the immunoreaction occurred in S-antigen-positive pinealocytes of the pineal end-vesicle, but was absent from S-antigen-immunoreactive pinealocytes of the stalk region. In the rat, AFRU-immunoreaction was restricted to S-antigen-immunoreactive pinealocytes found in the deep portion of the pineal organ and the habenular region. These findings support the concept that several types of pinealocytes exist, which differ in their molecular, biochemical and functional features. They also indicate the possibility that the AFRU- and ASO-immunoreactive material found in certain pinealocytes might represent a proteinaceous or peptidic compound, which is synthesized and released from a specialized type of pinealocyte in a hormone-like fashion. This cell type may share functional characteristics with peptidergic neurons or paraneurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00226496
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Ultrastructure of the meninges at the site of penetration of veins through the dura mater, with particular reference to Pacchionian granulations (1988)
    Springer
    Cell & tissue research 251 (1988), S. 621-631 
    Details
    ISSN: 1432-0878
    Keywords: Perivascular space ; Cerebrospinal fluid compartments ; Dura mater ; Pacchionian granulations ; Rat ; Cebus apella, Callitrix jacchus (Primates)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary At the sites where a vein penetrates through the dura mater, two aspects deserve particular attention: (i) The delineation of the perivascular cleft, a space belonging to the interstitial cerebrospinal fluid (CSF) compartment, toward the interior hemal milieu of the dura mater. (ii) The relationship between the perivascular arachnoid layer and the subdural neurothelium at the point of vascular penetration. These problems were investigated in the rat and in two species of New-World monkeys (Cebus apella, Callitrix jacchus). Concerning the first aspect, tight appositions of meningeal cells to the vessel wall, the basal lamina of which is widened and enriched with microfibrils, prevent communication between the interstitial CSF in the perivascular cleft and the hemal milieu in the dura mater. With reference to the second aspect, the perivascular arachnoid cells are transformed into neurothelial cells at the point where they become exposed to the hemal milieu of the dura mater and subsequently continuous with the subdural neurothelium. Leptomeningeal protrusions encompassing outer CSF space can penetrate into the dura mater. These protrusions may expand and branch repeatedly, forming along the wall of the durai sinus Pacchionian granulations. At these sites, however, the structural integrity of the sinus wall and the Pacchionian granulation is not lost. Numerous vesiculations not only in the sinus and vascular walls, but also in the cellular arrays of the Pacchionian granulations or paravascular leptomeningeal protrusions indicate mechanisms of transcellular fluid transport. Moreover, the texture of the leptomeningeal protrusions favors an additional function of these structures as a “volume” buffer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214011
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Binding of intravenously injected antibodies against laminin to developing and mature endocrine glands (1988)
    Springer
    Cell & tissue research 251 (1988), S. 171-181 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Basal lamina ; Laminin ; Anterior pituitary gland ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To determine whether circulating antibodies against laminin can bind in vivo to basement membranes within endocrine glands, affinity-purified sheep or rabbit anti-laminin IgG was intravenously injected into rats. One to five hours after injection, anti-laminin IgG was bound to all basement membranes of adrenal and anterior pituitary glands of mature as well as 2-day-old newborn rats as shown by immunofluorescence microscopy. After the injection of anti-laminin conjugated directly to horseradish peroxidase (HRP), HRP reaction product was also present throughout adrenal and pituitary basement membranes in mature and immature glands 1–5 h post-injection. Ultrathin Lowicryl sections from rats that received unconjugated rabbit anti-laminin IgG 1 h prior to fixation with paraformaldehyde were labeled directly with anti-rabbit IgG-colloidal gold. In these cases, gold also bound specifically over the lamina densa and lamina rara. When adrenal or pituitary glands from mature rats were examined by immunofluorescence 1 week after the injection of sheep anti-laminin IgG, the patterns and amounts of bound sheep IgG were indistinguishable from those observed 1 h after injection. In contrast, significantly less fluorescence was present in glands from 7-day-old rat pups that had received anti-laminin IgG 5 days earlier. In addition, when anti-laminin IgG-HRP was injected into newborns and glands were fixed 5 days later, lengths of labeled endothelial and epithelial basement membranes were often interspersed with unlabeled lengths in zones of cellular proliferation in the outer adrenal cortex and throughout the pituitary gland. These results indicated that unlabeled basement membranes in these regions were probably assembled after the injection of anti-laminin IgG, which would also explain diminished labeling of basement membranes in these animals. Despite the continued presence of heterologous anti-laminin IgG within endocrine basement membranes, however, rat IgG, rat C3, inflammatory cells, or histologic abnormalities were observed in neither newborn nor adult glands under the conditions examined here. Sections from rats injected with control IgG or control IgG-HRP were entirely negative by immunofluorescence, immunoperoxidase, and immunogold techniques. We therefore conclude that (1) apparently large amounts of circulating anti-laminin IgG can bind to adrenal and pituitary basement membranes, and (2) at least some of these basement membranes are assembled during development by progressive splicing of newly synthesized matrix into that already present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215462
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Nerve growth factor-inducible, large external (NILE) glycoprotein in developing rat cerebral cells in culture (1988)
    Springer
    Cell & tissue research 252 (1988), S. 181-190 
    Details
    ISSN: 1432-0878
    Keywords: Embryonic rat brain ; Cell culture ; Development ; NILE-glycoprotein ; Neurons ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fetal rat cerebral cells underwent neuronal differentiation in culture. This process was accompanied by distinct changes in the cellular glycoprotein pattern. The incorporation of [3H]-fucose into two proteins of apparent molecular weights of 30000 and 60000 daltons was significantly decreased and specific developmental changes were observed in a group of glycoproteins with high molecular weights (150000–250000 dalton). By means of indirect immunoprecipitation one of them was identified as NILE gp (nerve growth factor-inducible large external) glycoprotein (200000 dalton), a marker of central and peripheral neurons. Its developmental expression on neurons of dissociated rat cerebral cultures was studied using the indirect immunofluorescence technique and compared to the fluorescent-labeling pattern of other neuronal markers. Neurons expressing NILE gp were detected as early as after one day in culture. No preferential staining of neuntes versus cell bodies was observed. Two classes of NILE gp-positive cells were identified. One group consisted of a rounded cell-type, whereas the other group was represented by larger, more spindle-shaped neurons with a limited number of neuritic processes. In most cases one of these neuritic processes was preferentially labeled. Astroglia cells, as identified by immunolabeling with antisera against the glial acidic fibrillary protein, were observed to develop and mature after the first week in culture. NILE-positive neurons were found to be positioned in close association with glial cell processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213840
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Study on the origin of apical tubules in ileal absorptive cells of suckling rats using concanavalin-A as a membrane-bound tracer (1988)
    Springer
    Cell & tissue research 251 (1988), S. 511-521 
    Details
    ISSN: 1432-0878
    Keywords: Endocytosis ; Absorptive cells ; Ileum ; Intestine, small ; Apical tubules ; Membrane recycling ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ileal absorptive cells of suckling rats exhibit high levels of endocytic activity being engaged in nonselective uptake of macromolecules from the intestinal lumen. The apical cytoplasm usually contains an extensive network of small, membrane-limited tubules (apical tubules: AT), in addition to newly formed endocytic vesicles and large endocytic vacuoles. To determine whether the AT are directly involved in the endocytic process by carrying the tracer into the cell, we have analysed movements of the apical cell membrane of the ileal absorptive cells by using a membrane-bound tracer (horseradish peroxidase-labelled cancanavalin-A: Con-A HRP). The ileal absorptive cells were exposed in vitro to Con-A HRP for 10 min at 4° C, incubated for different times in Con-A free medium at 37° C, and prepared for electron microscopy. After 1 min incubation at 37° C, invaginations of the apical cell membrane, including coated pits, and endocytic vesicles were labelled with HRP-reaction product, whereas the AT and large endocytic vacuoles were negative. After 2.5 min, almost all the large endocytic vacuoles were labelled with reaction product, which was seen in their vacuolar lumen and along the luminal surface of their limiting membrane. A few AT with reaction product were seen in the apical cytoplasm; they were in frequent connection with the reaction-positive large endocytic vacuoles. With increasing incubation time, the number of the labelled AT increased. Thus, after 15 min at 37° C, the apical cytoplasm was fully occupied by the reaction-positive AT. The ends of these AT were often continuous with small spherical coated vesicles. No reaction product was detected in the Golgi complex at any time after incubation. These observations indicate that the AT located in the apical cytoplasm probably originate by budding off from the large endocytic vacuoles, rather than being involved in the process of endocytosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213998
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Innervation of periodontal ligament and dental pulp in the rat incisor: An immunohistochemical investigation of neurofilament protein and glia-specific S-100 protein (1988)
    Springer
    Cell & tissue research 251 (1988), S. 13-21 
    Details
    ISSN: 1432-0878
    Keywords: Periodontal ligament ; Incisor ; Neurofilament protein ; S-100 protein ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nervous elements in the periodontal ligament and dental pulp of rat incisors were investigated by means of immunohistochemistry for neurofilament protein (NFP) and glia-specific S-100 protein. The periodontal ligament in the incisors was densely innervated by NFP-immunoreactive nerve fibers; the distribution of the nerve fibers and their terminations differed markedly from those in molars. NFP-positive, thick nerve bundles entered the lingual periodontal ligament through slits located in the mid-region of the alveolar socket, and immediately formed numerous Ruffini-like corpuscles. In the labial periodontal ligament, all of the NFP-immunoreactive nerve fibers terminated in free endings. The restricted location of the stretch receptor, Ruffini-like corpuscle, in the lingual periodontal ligament appears to be an essential element, because this region is regularly extended during mastication. The nervous elements were restricted to the alveolar half of the periodontal ligament in every region; they avoided the dental half of the periodontal ligament, which presumably moves continuously with the tooth. Pulpal nerve fibers in incisors also showed a characteristic distribution different from those in molars; individual nerve fibers with beaded structures ran in the center of the pulp toward the incisai edge, and did not form the subodontoblastic nerve plexus of Raschkow. Immunostaining for S-100 protein revealed a distribution pattern of nervous elements similar to that for NFP, suggesting that the nerves supplying the periodontal ligament and dental pulp were mostly covered by a Schwann sheath.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215442
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Abundant GABAergic innervation of rat posterior pituitary revealed by inhibition of GABA-transaminase (1988)
    Springer
    Cell & tissue research 251 (1988), S. 59-64 
    Details
    ISSN: 1432-0878
    Keywords: Posterior pituitary ; Immunocytochemistry ; Anti-GABA ; GABA-transaminase ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An antibody against gamma-aminobutyric acid (GABA) was used to identify GABAergic elements immunocytochemically in the rat posterior pituitary. In order to increase the intracellular concentration of GABA, rats were treated with the GABA-transaminase inhibitor gamma-vinyl-GABA (GVG). Light-microscopic observations of Vibratome and semithin sections revealed the presence of numerous immunoreactive nerve fibers throughout the neural lobe; the mean number and length of these fibers increased by 90% after GVG treatment. Electron microscopy demonstrated the immunostained axons to be of small diameter. The reaction product was confined to small vesicles. No immunostaining occurred in pituicytes. The richness of the GABAergic innervation of the neural lobe contrasts with previous reports using antibodies against glutamate decarboxylase and supports the idea that GABA participates in the presynaptic control of neurosecretion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215447
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Evidence for neuroendocrine regulation of preadipocyte proliferation and differentiation (1988)
    Springer
    Cell & tissue research 251 (1988), S. 65-70 
    Details
    ISSN: 1432-0878
    Keywords: Adipose tissue ; Cell proliferation ; Cell differentiation ; Histochemistry ; Swine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cells in fetal adipose tissue and cells in vitro are characterized by rapid proliferation. Serum factors have been shown to be important for the rapid proliferation of cells in vitro. The present experiment was performed to determine if neuroendocrine regulatory mechanisms of the fetus can influence the actions of serum factors on preadipocyte proliferation and differentiation in vitro. Sera were obtained from decapitated fetal pigs and intact littermates during gestation. Sera were tested for their effects on primary cultures of preadipocytes and stromalvascular cells derived from inguinal adipose tissue of young Sprague-Dawley rats. Coverslip cultures were used for histochemical analysis of enzymes after 12 days of incubation with test media. Analysis of growth curves produced from sequential [3H]-thymidine labeling indicated that fetal age influences rates of proliferation. Sera from decapitated fetal pigs specifically reduced the number of proliferating preadipocytes in culture. Sera from decapitated fetal pigs induced a minimum of 50% less differentiation of sn-glycerol-3-phosphate dehydrogenase activity than sera from intact pigs at all fetal ages. Histochemical staining for enzymes of differentiating preadipocytes was also reduced in cultures incubated with sera from decapitated fetal pigs in comparison to sera from intact pigs. The present study has demonstrated that the in vivo effect of decapitation on fetal adipose tissue development is a consequence of alterations in systemic factors present in serum in response to removal of central regulation by the hypothalamic-pituitary axis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215448
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Immumochemical and immunocytochemial characterization of a novel monoclonal antibody recognizing a 140 kDa protein in cerebral pericytes of the rat (1988)
    Springer
    Cell & tissue research 252 (1988), S. 543-555 
    Details
    ISSN: 1432-0878
    Keywords: Monoclonal antibody ; Blood-brain barrier ; Cerebral pericytes ; Transporting epithelia ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A monoclonal antibody that recognizes a 140 kDa peripheral plasma membrane protein in pericytes of nervous tissues of the rat is described. Microvessels of brain cortex and perineurium of peripheral nerves are shown to react positively to this antibody. The antigen is absent in brain regions that lack a blood-brain barrier, i.e., choroid plexuses and area postrema. Antigen expression starts as early as day 18 of embryonic development. By means of immuno-electron microscopy the 140 kDa antigen was detected as clusters along the entire circumference of cerebral pericytes. The same antigenic determinant is also expressed in apical domains of plasma membranes of a variety of transporting epithelia, such as hepatocytes, enterocytes of the small intestine, and epithelial cells of proximal tubules of the kidney. We postulate the 140 kDa protein as being a constituent of the pericytes involved in regulative functions of the blood-brain barrier.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216641
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Orthogonal arrays of particles in non-pigmented cells of rat ciliary epithelium: Relation to distribution of filipin- and digitonin-induced alterations of the basolateral membrane (1988)
    Springer
    Cell & tissue research 252 (1988), S. 165-173 
    Details
    ISSN: 1432-0878
    Keywords: Ciliary epithelium ; Orthogonal arrays of particles ; Filipin ; Freeze-fracture ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary It has been suggested that orthogonal arrays of particles may increase the rigidity of plasma membrane, as does cholesterol. Therefore, using freeze-fractured non- pigmented ciliary epithelium, the distribution of such arrays was compared to the distribution of membrane deformations induced by the sterol-probes filipin and digitonin in different domains of the basolateral plasma membrane. The distribution of orthogonal arrays of particles was homogeneous between different regions of the basolateral membrane of the non-pigmented ciliary epithelium, while the number of filipin-induced alterations was nearly 4 times higher in the membrane domains not in contact with the basal lamina than in domains in contact with it. Contrary to the homogeneous distribution of arrays, digitonin-induced deformations also differed markedly in these two basolateral membrane domains. Considering that a marked positive response to sterol probes implies a high sterol content, we conclude that orthogonal arrays of particles can occur in plasma membrane regions well-provided with cholesterol and not in direct contact with the basal lamina. Other possible roles of these arrays are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213838
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    44-kDal bone phosphoprotein (osteopontin) antigenicity at ectopic sites in newborn rats: kidney and nervous tissues (1988)
    Springer
    Cell & tissue research 251 (1988), S. 23-30 
    Details
    ISSN: 1432-0878
    Keywords: Bone phosphoprotein ; Osteopontin ; Kidney ; Inner ear ; Trigeminal nerve ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Previous immunohistochemical data have shown that the 44-kDal bone phosphoprotein (44K BPP, also called sialoprotein I or oestopontin) recently isolated in our laboratory was synthesized by osteoblasts and osteocytes and was expressed early during differentiation of boneforming cells. We report here the presence of 44K BPP antigenicity at certain ectopic sites, namely, the proximal-convoluted tubule of the kidney, neurons, sensory and secretory cells in the internal ear. To insure specificity and reproducibility, different immunohistochemical methods were used and affinity-purified antibodies against two separate preparations of pure 44K BPP were tested. In the cells of the proximal-convoluted tubule, 44K BPP immunoreactivity was observed within apical endocytotic vacuoles and within lysosomes. This staining thus correlates with the degradation of the 44K BPP epitope which we previously demonstrated to occur in serum. On the other hand, in the neurons of the acoustic ganglion and the sensory cells of the macula, 44K BPP immunoreactivity was associated with the Golgi apparatus indicating synthesis and secretion by these cells. The finding that the 44K BPP (or a structurally related molecule) is synthesized by neurons and neuroepithelial cells deserves further investigation with respect to a possible embryologie relationship between neuroectodermal cells and the precursors of some bone forming-cells of the skull.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215443
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    The lattice arrangement of the collagen fibres in the submucosa of the rat small intestine: scanning electron microscopy (1988)
    Springer
    Cell & tissue research 251 (1988), S. 117-121 
    Details
    ISSN: 1432-0878
    Keywords: Collagen ; Submucosa ; Intestine ; Scanning electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The three-dimensional architecture of the submucosal collagen fibres of the rat (3 weeks old) small intestine was examined by scanning electron microscopy using a selective microdissection method. The main framework of the submucosa was composed of two arrays of collagen fibre bundles running diagonally around the intestinal wall, one set in a clockwise direction, the other counterclockwise. These fibre bundles were about 5 μm in diameter and were oriented at a range of angle ± 30°–50° to the longitudinal axis of the intestine. With the advantage of the SEM observation it was demonstrated that these fibres in different arrays did not constitute two separate layers but interwove to form a unified lattice sheet. An irregular network of fine collagen fibrils over the main framework was also seen. The significance of their arrangement is discussed with respect to the skeletal function of the submucosa in the intestine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215455
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Adhesion, proliferation, and adipogenesis in primary rat cell cultures: effects of collagenous substrata, fibronectin, and serum (1988)
    Springer
    Cell & tissue research 251 (1988), S. 123-128 
    Details
    ISSN: 1432-0878
    Keywords: Adipocyte ; Primary culture ; Collagen ; Fibronectin ; Serum ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of collagenous substrata, fibronectin, and fetal bovine serum on the adhesion, proliferation, and adipogenesis of rat stromal-vascular cells are reported. There was no effect on initial stromal-vascular cell-attachment by fetal bovine serum or fibronectin. The number of cells attached to a hydrated collagen-gel was almost twice (P〈0.04) the number attached to dried collagen-gel or dried denatured collagen-gel. Total number of cells after 5 days in culture was similar among the collagenous substrata and among the treatments with or without fibronectin in the growth media. Total number of cells increased significantly (P〈0.02) with 10% FBS. Adipocytic formation was inhibited by hydrated collagen-gel (P〈0.02) compared to dried collagen-gel or dried, denatured collagenous substrata. An interaction occurred between dried, denatured gel and fetal bovine serum so that total formation of adipocytes increased by increasing the level of fetal bovine serum (P〈0.07). Adipocytic formation was inhibited by hydrated collagen-gel at all levels of fetal bovine serum. The percentage of cells that converted to adipocytes was significantly lower (P〈0.01) on hydrated collagen-gel compared to dried, denatured or dried collagen-gel. Percentage of conversion was not significantly different among levels of fetal bovine serum, although this percentage increased as fetal bovine serum level increased. Adipocytic conversion was not different between fibronectin-treated or untreated cells. Morphology of stromal vascular cells was similar on dried collagen and dried, denatured collagen-gel, but tended to remain bipolar on hydrated collagen-gel. These studies indicate that fetal bovine serum in combination with the extracellular matrix (dried, denatured collagen) increased the differentiation of rat stromal-vascular cells into adipocytes, and that hydrated collagen inhibited differentiation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215456
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Ventricular and atrial myocytes of newborn rats synthesise and secrete atrial natriuretic peptide in culture: Light-and electron-microscopical localisation and chromatographic examination of stored and secreted molecular forms (1988)
    Springer
    Cell & tissue research 251 (1988), S. 161-169 
    Details
    ISSN: 1432-0878
    Keywords: Atrial natriuretic peptide ; Ventricular myocytes ; Atrial myocytes ; Cell culture ; Secretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We have demonstrated that atrial natriuretic peptide-like immunoreactivity is stored and secreted by ventricular and atrial myocytes in dissociated cell culture preparations from the heart of newborn rat. Culture preparations were maintained in either foetal calf serum-supplemented medium 199 or in hormone-supplemented, serum-free medium 199. The presence of atrial natriuretic peptidelike immunoreactivity in the cultured myocytes was demonstrated at both light-and electron-microscopical levels. Release of atrial natriuretic peptide-like immunoreactivity into the culture medium was measured by radioimmunoassay; molecular forms of the stored and secreted peptide were determined by gel column chromatography. The atrial natriuretic peptide-like immunoreactivity of cultured atrial and ventricular myocytes was concentrated in the perinuclear cytoplasm and was localised to electron-dense secretory granules. The number of immunoreactive ventricular myocytes and the intensity of their immunofluorescence changed with time in culture and was higher in cultures in foetal calf serum-supplemented medium than in serum-free medium. Gamma-atrial natriuretic peptide was stored and released by cultured atrial and ventricular myocytes, but was broken down to alpha-atrial natriuretic peptide in the growth medium. This process was foetal calf serum-independent, since it occurred in both the media used, indicating that cardiac myocytes in culture may release a factor that cleaves gamma-atrial natriuretic peptide to form alphaatrial natriuretic peptide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215461
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Transient involvement of enkephalins in both the sympathetic and parasympathetic innervations of the submandibular gland of rats (1988)
    Springer
    Cell & tissue research 253 (1988), S. 529-537 
    Details
    ISSN: 1432-0878
    Keywords: Enkephalin-nerves ; Transient appearance ; Submandibular gland ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A time course study with enkephalin(Enk)-like immunoreactivity has revealed that nerve fibers intensely immunoreactive for Enk-8 appeared transiently only during the postnatal week 2 and 4 within the acini as well as in the inter- and intralobular connective tissues of the submandibular gland of rats. At these stages numerous nerve fibers immunoreactive for tyrosine hydroxylase (TH) appeared also in the inter- and intralobular connective tissues and within the acini. Coincidently with these postnatal stages, abundant Enk-immunoreactive principal ganglion cells appeared in the superior cervical ganglion. These were not immunoreactive for neuropeptide tyrosine (NPY). A substantial number of Enk-immunoreactive ganglion cells were also present in the submandibular ganglia at these younger postnatal stages. Superior cervical ganglionectomy at these stages resulted in a marked decrease in number of the inter- and intralobular Enk-immunoreactive nerve fibers, a slight decrease in number of the intraacinar Enk-immunoreactive nerve fibers, and almost complete disappearance of intraglandular TH-immunoreactive nerve fibers. Immuno-electron-microscopic analysis revealed that Enk-immunoreactive nerve fibers in the submandibular gland were identified as electron-dense neuronal profiles enclosed by Schwann cells in the inter- and intralobular connective tissues and those directly apposed to secretory cells within the acini. They contained small clear vesicles mixed with some large granular vesicles. After postnatal week 6, no Enk-immunoreactive nerve fibers were detected in the submandibular gland, and no TH-immunoreactive nerve fibers were seen within the acini, while TH-immunoreactive nerve fibers remained numerous in the inter- and intralobular connective tissues. These findings indicate that both sympathetic and parasympathetic nerve fibers exhibit Enk-like immunoreactivity transiently during postnatal weeks 2 and 4. It is further indicated that the inter- and intralobular nerve fibers lose Enk-like immunoreactivity while the intraacinar fibers disappear at the adult stage.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219743
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Morphometrical analysis of the gap-junctional area in parenchymal cells of the rat liver after administration of dibutyryl cAMP and aminophylline (1988)
    Springer
    Cell & tissue research 252 (1988), S. 611-618 
    Details
    ISSN: 1432-0878
    Keywords: Gap junctions ; cAMP ; Theophylline ; Freeze-fracture ; Liver ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In view of the presumed involvement of gap junctions in the coordination of metabolic activities, the influence of cAMP as a regulatory signal of cell metabolism on gap junctions of hepatocytes has been examined. Male rats received two intraperitoneal doses of 10 mg dibutyryl cAMP/100 g body weight with a time interval of 2.5 h and were decapitated 2.5 h later. After this 5-h interval, analysis of freeze-fracture replicas of fixed liver tissue revealed an increase in the mean (± SEM) gap-junctional membrane portion on the lateral hepatocyte membranes from 0.049 + 0.003 (n = 66) in controls to 0.061 ± 0.003 (n = 70) in treated rats, while the configuration of the connexons appeared unaltered. This effect could not be reinforced by prior administration of aminophylline: the relative gapjunctional area is similarly extended from 0.054 ± 0.003 (n = 126) in the control group to 0.065 ± 0.004 (n = 105) in the experimental animals. Probing for the time course of the junctional response, a group of rats was sacrificed 3 h after the onset of treatment. Already within this time, the gapjunctional area is augmented from 0.042 ± 0.004 (n = 63) in the concurrent controls to 0.069 ± 0.006 (n = 42) in the treated rats. These statistically significant increases in area may suggest a stimulating effect of cAMP on gap junctions of hepatocytes in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216648
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Immunohistochemical identification of supportive cell types in the enteric nervous system of the rat colon and rectum (1988)
    Springer
    Cell & tissue research 251 (1988), S. 523-529 
    Details
    ISSN: 1432-0878
    Keywords: Glial fibrillary acidic (GFA) protein ; S-100 protein ; Supportive cells ; Intestine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The non-neuronal, supportive cells of the enteric nerve plexus were investigated in the colon and rectum of adult and developing rats by means of immunohistochemistry, utilizing antisera against GFA protein and S-100 protein. Immunoreactivity to GFA protein was almost exclusively found in cells associated with the myenteric plexus and a small number of cells within the submucous ganglia. On the other hand, the use of S-100 protein antiserum resulted in the visualization of all supportive elements in the enteric nervous system. However, two types of supportive cells could be tentatively differentiated in the enteric nerve plexus during the second week of postnatal development, using GFA protein and S-100 protein antisera; GFA protein-positive cells were clearly discernible from S-100 protein-positive cells in terms of both the morphological profiles and immunohistochemical properties. It was assumed that at least two different types of supportive cells are contained in the enteric nerve plexus. We suggest that in the enteric nervous system the terms “glial cells” and “Schwann cells” should be employed to designate the supportive cells containing GFA and S-100 proteins, and cells containing S-100 protein, respectively. We discuss the possibility that glial cells are associated with the parasympathetic preganglionic fibres directly derived from the central nervous system, while Schwann cells originate from the neural crest.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213999
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Immunohistochemical evidence for the presence of calcium-binding proteins in enteric neurons (1988)
    Springer
    Cell & tissue research 252 (1988), S. 79-87 
    Details
    ISSN: 1432-0878
    Keywords: Calcium-binding protein ; Enteric nervous system ; Intestine ; Immunocytochemistry ; Guinea-pig ; Rat ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunoreactivity for vitamin D-dependent calcium-binding protein (CaBP) has been localized in nerve cell bodies and nerve fibres in the gastrointestinal tracts of guinea-pig, rat and man. CaBP immunoreactivity was found in a high proportion of nerve cell bodies of the myenteric plexus, particularly in the small intestine. It was also found in submucous neurons of the small and large intestines. Immunoreactive nerve fibres were numerous in the myenteric ganglia, and were also common in the submucous ganglia and in the intestinal mucosa. Immunoreactive fibres were rare in the circular and longitudinal muscle coats. In the myenteric ganglia of the guinea-pig small intestine the immunoreactivity is restricted to one class of nerve cell bodies, type-II neurons of Dogiel, which display calcium action potentials in their cell bodies. These neurons were also immunoreactive with antibodies to spot 35 protein, a calcium-binding protein from the cerebellum. From the distribution of their terminals and the electrophysiological properties of these neurons it is suggested they might be sensory neurons, or perhaps interneurons. The discovery of CaBP in restricted sub-groups of enteric neurons may provide an important key for the analysis of their functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213828
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Pathway of nerves with vasoactive intestinal polypeptide-like immunoreactivity to the major cerebral arteries of the rat (1988)
    Springer
    Cell & tissue research 251 (1988), S. 275-280 
    Details
    ISSN: 1432-0878
    Keywords: Cerebral arteries ; Vasoactive intestinal polypeptide ; Vascular innervation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pathway of nerves with vasoactive intestinal polypeptide(VIP)-like immunoreactivity to the major cerebral arteries was studied in rats by means of the indirect immunofluorescent method. The fibers are densely distributed in the ethmoidal nerves and in the adventitia of both the external and internal ethmoidal arteries. Section of both ethmoidal nerves and external ethmoidal arteries before they enter the cranial cavity induced a marked reduction of VIP-like immunoreactive fibers in the walls of the vessels of the circle of Willis and its major branches. However, section of the external ethmoidal artery alone did not result in visible changes of the nerves around major cerebral arteries. The present study suggests that VIP-like immunoreactive fibers surrounding major cerebral arteries of the rat arise from fibers in the ethmoidal nerve showing immunoreactivity to VIP.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215834
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Morphology of smooth muscle cells in the rat thoracic duct (1988)
    Springer
    Cell & tissue research 251 (1988), S. 243-248 
    Details
    ISSN: 1432-0878
    Keywords: Thoracic duct ; Smooth muscle cell ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The three-dimensional cytoarchitecture and ultrastructure of the smooth muscle cells in the wall of the rat thoracic duct were investigated by scanning and transmission electron microscopy. The muscle layer basically consists of a single layer of circularly arranged cells. The smooth muscle cell is fusiform or ribbon-like in shape, as in veins or venules with a similar or smaller diameter. Connections by spinous processes are observed between adjacent muscle cells along their length. Spot-like membrane contacts frequently occur in areas where facing membranes are closely apposed. These are thought to be gap junctions and may be responsible for electrical coupling and mechanical attachment. Large invaginations arranged regularly in rows on the surface of the smooth muscle cells can be observed. These invaginations are closely associated with a flattened sarcoplasmic reticulum, and caveolae tend to open into the invaginations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215831
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Ultrastructural immunocytochemical localization of l-glutamate decarboxylase and GABA in rat pancreatic zymogen granules (1988)
    Springer
    Cell & tissue research 252 (1988), S. 191-197 
    Details
    ISSN: 1432-0878
    Keywords: GABA ; Glutamate decarboxylase ; GABA transaminase ; Exocrine pancreas ; Immunocytochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural immunohistochemical localization of gamma aminobutyric acid (GABA) and its regulating enzymes, l-glutamate decarboxylase (GAD) and gamma aminobutyrate-α-ketoglutarate transaminase, was determined utilizing an immunogold post-embedding protocol in pancreatic exocrine tissue. Within the acinar cell, GABA and its biosynthetic enzyme, GAD, were localized in zymogen granules. Quantitative analysis of the GABA immunoreactivity in the acinar cell revealed 1.7±0.5 gold particles/μm2 over the cytoplasm, 36.6±14.1 gold particles/ μm2 over the zymogen granules, and 2.9±2.1 gold particles /μm2 over the mitochondria. Quantitative analysis of the distribution of colloidal gold particles, representing glutamate decarboxylase immunoreactivity in the acinar cells, revealed 38.4±2.5 gold particles/μm2 over the zymogen granules, 4.7±1.1 gold particles/μm2 over the mitochondria and 6.3±0.5 gold particles/μm2 over the remainder of the cytoplasm. Substitution of normal sheep serum for the sheep anti-glutamate decarboxylase serum revealed a significant (p〈 0.001) decrease of the colloidal gold particle distribution over the zymogen granules and cytoplasmic compartments of the acini. Gamma aminobutyrate -α-ketoglutarate transaminase, the catabolic enzyme for GABA, was not detected in the mitochondria, zymogen granules, and cytoplasm of the acinar cell, suggesting that GABA is not catabolized within the acinar cell. Preabsorption and substitution controls resulted in an absence of labeling. These results suggest that GABA may act extracellularly and/or have a role within the zymogen granule in the exocrine pancreas.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213841
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Selective decrease of immunoreactive tyrosine hydroxylase in nigrostriatum of adult male rats after N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment (1988)
    Springer
    Cell & tissue research 253 (1988), S. 251-258 
    Details
    ISSN: 1432-0878
    Keywords: MPTP ; Rat ; Nigrostriatum ; Parkinsonism ; Immunocytochemistry ; Tyrosine hydroxylase ; Animal model ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Several laboratories have reported that N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine causes damage to the nigral dopamine neurons of man, monkey, and mouse. Controversial data suggest that a rat model of Parkinsonism may be possible. Although loss of dopamine cells has not been detected in the rat brain, our immunocytochemical studies show that immunoreactive tyrosine hydroxylase, the rate-limiting enzyme which synthesizes dopamine, is significantly reduced in concentration, or its antigenicity altered, in substantia nigra/pars compacta as well as the caudate nucleus. Optical density measurements demonstrate the reduction or alteration of immunoreactive tyrosine hydroxylase in nigro-striatal neurons, indicating that axonal terminals, as well as parent perikarya, may be sensitive to the drug. After treatment, abnormal morphological remodelling may result in the affected neuronal processes, perhaps indicating sublethal toxicity, followed by slow recovery. Despite the lack of nigral cell death, it is proposed that the present data support the use of the rat as a model to investigate the early effects of Parkinsonism induced by this agent, and the biological mechanisms of cellular recovery.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221761
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Developmental appearance of the Ca2+-binding proteins parvalbumin, calbindin D-28K, S-100 proteins and calmodulin during testicular development in the rat (1988)
    Springer
    Cell & tissue research 252 (1988), S. 359-365 
    Details
    ISSN: 1432-0878
    Keywords: Calcium ; Parvalbumin ; Calbindin D-28K ; S-100 proteins ; Calmodulin ; Testis ; Male sexual hormones ; Leydig cells ; Spermatogenesis ; Rat (SIV-50)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Calcium and intracellular Ca2+-binding proteins are possibly involved in hormone production and spermatogenesis in rat testis. Parvalbumin, calbindin D-28K, S-100 proteins and calmodulin were localized in the Leydig cells, which are sites of testosterone synthesis. Only the appearance of parvalbumin-immunoreactivity is closely correlated to testosterone production during development of the testes. Calbindin D-28K-immunoreactivity persisted in foetal-type Leydig cells and in adult-type Leydig cells at all stages of development. S-100-immunoreactivity was low during all foetal stages, absent between birth and puberty, and increased thereafter. Calmodulin staining is most prominent in the cytoplasm of developing spermatocytes and of maturing spermatids. All four proteins co-exist in the seminiferous tubules. The distinct localization and developmental appearance of these proteins suggests different regulatory roles in Leydig cell function and spermatogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214378
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Development of the esophageal muscles in embryos of the sea urchin Strongylocentrotus purpuratus (1988)
    Springer
    Cell & tissue research 252 (1988), S. 411-417 
    Details
    ISSN: 1432-0878
    Keywords: Myogenesis ; Sea urchin embryo ; Development ; Muscle ; Mesenchyme ; Strongylocentrotus purpuratus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Development of the esophageal muscles in embryonic sea urchins is described using light- and electron microscopy. The muscles develop from processes of about 14 cells of the coelomic epithelium that become immunore-active to anti-actin at about 60 h (12–14° C). Initially, eachmyoblast extends a single process with numerous fine filopodia around the esophagus. By 72 h the processes have reached the midline and fused with those from cells of the contralateral coelomic sac. Myoblasts begin to migrate out of the coelomic epithelium between 72 and 84 h. By 72 h the processes stain with the F-actin specific probe NBD-phallacidin. The contractile apparatus is not evident in transmission electron-microscopic preparations of embryos at 70 h, but by 84 h the contractile apparatus is present and the muscle cells are capable of contraction. Because the myoblasts migrate free of the coelomic epithelium and are situated on the blastocoelar side of the basal lamina, it is suggested that that they should be considered as a class of mesenchymal cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214384
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    TRH-like immunoreactivity in endocrine cells and neurons in the gastro-intestinal tract of the rat and guinea pig (1988)
    Springer
    Cell & tissue research 253 (1988), S. 347-356 
    Details
    ISSN: 1432-0878
    Keywords: Pancreas, endocrine ; Stomach ; Intestine ; Immunohistochemistry ; Thyrotropin-releasing hormone (TRH) ; Somatostatin ; Avian pancreatic polypeptide ; Insulin ; Gastrin ; Rat ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary By use of the indirect immunofluorescence technique, the cellular localization of thyrotropin-releasing hormone (TRH) was studied in the gastrointestinal tract of rats and guinea pigs of different ages. TRH-like immunoreactivity (LI) was observed in many pancreatic islet cells of young rats and guinea pigs but only in single cells of 6-month-old rats. In aged guinea pigs, a reduction in the number of TRH-positive cells was evident; however, numerous strongly fluorescent cells were still present. In the guinea pig, TRH-LI was in addition observed in gastrin cells in the stomach. TRH-positive nerve fibers occurred in the myenteric plexus of the oesophagus, stomach and intestine of the rat, and in the muscle layers of the guinea pig. These results suggest a functional role of TRH both as hormone and neuroactive compound in various portions and sites of the gastro-intestinal tract of the rat and guinea pig
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222291
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Are lysosomal enzymes involved in rapid damage in vertebrate muscle cells? (1988)
    Springer
    Cell & tissue research 253 (1988), S. 447-455 
    Details
    ISSN: 1432-0878
    Keywords: Lysosomes ; Muscle damage ; Calcium ; Lysosomotropic agents ; Phospholipase A2 ; Frog (Rana temporaria) ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Experiments with lysosomotropic agents suggest that the sarcotubular system subserves some of the functions of the lysosomal apparatus in frog skeletal muscle. Dinitrophenol or A23187 trigger lysosome labilization and myofilament damage in mammalian cardiac muscle. Lysolecithin labilizes isolated liver lysosomes, but has no action following phospholipase A2 activation in vivo. Zinc ions or a pHi of 7.5 do not protect against myofilament damage. In fractions from mammalian cardiac muscle, calcium and calmodulin do not cause lysosomal labilization whereas cGMP does but only at high concentration (10-4 M). It is concluded that lysosomal hydrolases play no significant part in rapid muscle damage. It is suggested that rises in [Ca]i activate two separate pathways causing (i) myofilament damage; (ii) sarcolemmal (and possibly lysosomal) membrane damage via phospholipase A2 and lipoxygenase activity. Dinitrophenol triggers both pathways independently and thus may cause lysosome labilization. The possibility that the sarcoplasmic reticulum is the site generating myofilament damage is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222302
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    The role of phospholipase A2 in calcium-induced damage in cardiac and skeletal muscle (1988)
    Springer
    Cell & tissue research 253 (1988), S. 457-462 
    Details
    ISSN: 1432-0878
    Keywords: Muscle damage ; Cardiac muscle ; Calcium ; Phospholipase A2 ; Lipoxygenase ; Cyclo-oxygenase ; Rana ttemporaria ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study compares the action of inhibitors of the eicosanoid cascade on calcium-induced myofilament damage in cardiac muscle of the perfused frog heart and incubated frog ventricle slices, and in skeletal muscle of incubated mammalian diaphragm and isolated and saponin-skinned amphibian pectoris cutaneous muscle. Mepacrine (10-5M) and indomethacin (3×10-6M) protected completely against myofilament damage induced by entry of calcium in the ‘calcium-paradox’ in frog heart. However, inhibition of phospholipase A2 (PLA2) (with chlorpromazine, 2×10-4M, or mepacrine, 10-5M, 5x10-5M), of cyclo-oxygenase enzymes (with indomethacin, 3x10-6M to 10-5M or BW755C, 3.8x10-4M), or of lipoxygenase enzymes (with BW755C, 3.8x10-4M or nordihydroguaiaretic acid, 2x10-6M or 5x10-6M) all failed in intact cardiac or skeletal muscle cells to prevent the myofilament damage that is rapidly triggered by 10-2M caffeine, 6x10-6M ruthenium red, 10-4M DNP or 5 μg ml-1 A23187. These agents also failed completely to protect against myofilament damage in saponin-skinned amphibian skeletal muscle when [Ca]i was raised to 8x10-6M. Thus, inhibition of PLA2 does not protect the myofilament apparatus against calcium released intracellularly, and it is suggested that mepacrine and indomethacin can block entry of calcium in the calcium-paradox in the amphibian heart. Chlorpromazine (2x10-4M) and mepacrine (10-3M) at zero [Ca] caused severe myofilament damage in skinned muscle, possibly due to an effect on membranes. Since inhibitors of PLA2 and of lipoxygenases prevent efflux of creatine kinase and sarcolemma damage in mammalian skeletal muscle, it is evident that experimentally-induced rises in [Ca]i (by caffeine or A23187) can trigger two separate pathways: (i) PLA2 and the arachidonic acid cascade which culminate in membrane damage, and (ii) a different, Ca-activated system that causes rapid damage of myofilaments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Structural changes produced in Kupffer cells in the rat liver by injection of lipopolysaccharide (1988)
    Springer
    Cell & tissue research 251 (1988), S. 205-214 
    Details
    ISSN: 1432-0878
    Keywords: Kupffer cells ; Granulocytes ; Ultrastructure ; Lipopolysaccharide ; Liver ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of Kupffer cells has been studied at various times after an intravenous injection of lipopolysaccharide of Salmonella abortus equii. The most prominent effects were: an increase in the number and dimensions of phagocytic vacuoles (often containing ingested LPS and neutrophilic granulocytes); mitochondrial damage, including disintegration of the matrix and cristae; an increase in the amount of dilated, lucent rough endoplasmic reticulum; presence of fat droplets in the cytoplasm. Five days after injection of lipopolysaccharide, the Kupffer cells had resumed their normal ultrastructure. Several minutes after injection of lipopolysaccharide, platelets adhered to the Kupffer and endothelial cells. Between one and six hours, neutrophilic granulocytes accumulated in the liver sinusoids. The resulting obstruction of the hepatic microcirculation most probably affected cellular ultrastructure by ischaemia. At three days, the number of Kupffer cells was doubled, and increased further at later time intervals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215466
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Fine-structural localization of neuropeptide tyrosine (NPY)-like immunoreactivity in the neuronal somata of colchicine-pretreated celiac ganglia of rats (1988)
    Springer
    Cell & tissue research 251 (1988), S. 221-224 
    Details
    ISSN: 1432-0878
    Keywords: Neuropeptide ; Intracellular localization ; Sympathetic ganglia ; Colchicine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In colchicine-pretreated cells of sympathetic ganglia, intensely NPY-immunoreactive material was localized within vacuoles and vesicles of the disorganized, widely dispersed Golgi apparatus. Intensely positive large granular vesicles, which are known to be one of major storage sites of various peptides in the autonomic nerve endings, were essentially unobserved in the perikaryal cytoplasm. The present finding provides evidence that one pool of NPY-like immunoreactivity is localized in the Golgi apparatus of colchicine-pretreated as well as normal sympathetic ganglion cells. It is also clear that visualization of NPY-immunoreactive somata by colchicine-pretreatment in the sympathetic ganglia is due to the accumulation of the neuropeptide in the disorganized Golgi stacks instead of increased amount of the large granular vesicles containing NPY.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215468
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Morphological studies on endocytosis of chondroitin sulphate proteoglycan by rat liver endothelial cells (1988)
    Springer
    Cell & tissue research 253 (1988), S. 39-45 
    Details
    ISSN: 1432-0878
    Keywords: Receptor-mediated endocytosis ; Chondroitin sulphate ; Colloidal gold ; Liver endothelial cells ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Endocytosis via the hyaluronic acid/chondroitin sulphate receptor of rat liver endothelial cells was studied ultrastructurally, by use of a probe consisting of chondroitin sulphate proteoglycan attached to 15-nm gold particles. The probe bound to the surface of the cells exclusively in coated regions of the plasma membrane. Internalization at 37° C took place in less than one minute during which time interval the bound probe was transferred to coated vesicles. Further transfer to lysosomes was delayed in association with an accumulation of probes in a prelysosomal compartment consisting of large vacuoles in which probes lined the inner aspect of the membrane. Transport to lysosomes occurred only after a lag phase of at least 40–60 min at 37° C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221737
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Distribution of peptide-immunoreactive nerves in the foetal and newborn guinea-pig caecum (1988)
    Springer
    Cell & tissue research 253 (1988), S. 105-114 
    Details
    ISSN: 1432-0878
    Keywords: Enteric nervous system ; Autonomic nervous system ; Development ; Vasoactive intestinal polypeptide ; Substance P ; [Met]enkephalin ; Somatostatin ; Guinea pig, Dunkin-Hartley
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of vasoactive intestinal polypeptide-, substance P-, [met]enkephalin- and somatostatin-like immunoreactive nerves was studied in the caecum from foetal guinea-pigs of 6–9 weeks gestation (i.e., approximately 1–4 weeks before birth) and 4–5-day-old guinea-pigs. Peptide-immunoreactive nerves were first detected in the myenteric and submucous plexuses and circular muscle layer at 6 weeks of gestation and in the mucosa at 7 weeks of gestation. The density of fibres in these layers increased during prenatal development until, by 9 weeks of gestation, their distribution resembled that seen in the postnatal animals. This distribution was similar to that described previously in adult animals. A different pattern of development was observed in the caecal taenia coli muscle. Peptide-immunoreactive fibres were not detected until 8 weeks of gestation in this tissue layer, and were then only sparsely distributed. A dramatic increase in the number of labelled fibres, however, occurred between 8 and 9 weeks of gestation. Further, vasoactive intestinal polypeptide- and substance P-immunoreactive fibres were more numerous in the taeniae coli of 9-week-old embryos than in those of postnatal animals. Thus, the guinea-pig enteric nervous system, which in many respects is well-developed at the time of birth, may still be undergoing developmental changes at this time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221745
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Developmental study of neuropeptide Y-like immunoreactivity in the neurohypophysis and intermediate lobe of the rhesus monkey (Macaca mulatta) (1988)
    Springer
    Cell & tissue research 254 (1988), S. 499-509 
    Details
    ISSN: 1432-0878
    Keywords: Neuropeptide Y ; Immunohistochemistry ; Pituitary ; Development ; Aging ; Neurohypophysis ; Intermediate lobe ; Hypothalamo-hypophyseal portal vessels ; Neuroendocrine regulation ; Macaca mulatta (Primates)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The purpose of this study was to examine the development and distribution of neuropeptide Y-immunoreactive fibers in the neurohypophysis of the rhesus monkey (Macaca mulatta) throughout life and the relationship of these fibers to the hypothalamo-hypophyseal portal vasculature. In rhesus monkeys, which varied in age from fetal life to 34 years, neuropeptide Y-immunoreactive fibers were present at all ages examined. In adult monkeys, varicose neuropeptide Y-labeled fibers were concentrated in the upper infundibular stem in association with capillary loops of the portal vasculature and the long portal vessels. Other fibers travelled down the infundibular stem and were distributed at the junction of the lower infundibular stem and infundibular process in the vicinity of the short portal vessels. In the infundibular process, neuropeptide Y-immunoreactive fibers were concentrated along the border of the intermediate lobe. Other stained fibers were sparsely distributed in the infundibular process and were often associated with small vessels. Neuropeptide Y-immunoreactivity was also located in a few fibers and cells of the intermediate lobe. Very few labeled fibers were seen in the fetal neurohypophysis, but their number increased gradually during the first postnatal year. At two years of age, a high density of stained fibers was observed, especially in the infundibular process. The number of axons in the infundibular process was lower at 12 years and continued to decline until 34 years of age. Neuropeptide Y may modulate hormone release at these sites and may also be released directly into vessels in the infundibular process. The close association of neuropeptide Y-labeled fibers with capillaries of the portal vasculature strongly suggests that neuropeptide Y is released into the portal blood of monkeys throughout life and may influence hormone secretion from the anterior pituitary gland.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00226499
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Analysis of the expression of extensin and p33-related cell wall proteins in carrot and soybean (1988)
    Springer
    Molecular genetics and genomics 211 (1988), S. 393-399 
    Details
    ISSN: 1617-4623
    Keywords: Cell wall ; Wounding ; Proline-rich proteins ; Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have identified p33 as a cell wall protein in carrot storage roots that increases in the cell wall after wounding, using antibodies raised against a synthetic peptide derived from the p33 cDNA sequence. The mRNA encoding p33 increases markedly within 1 h after wounding in carrots, indicating that p33 may be involved in one of the early cellular responses to physical damage. In contrast with extensin, p33 mRNA does not accumulate in carrot roots in response to ethylene or in carrot suspension culture cells incubated in the presence of a crude endogenous elicitor fraction. These results indicate that the wound-induced signals responsible for the synthesis of p33 and extensin after wounding are different. Protein immunologically related to carrot p33 and RNA transcripts homologous to p33 cDNA sequences were detected in the apical hook of the soybean seedling indicating that a cell wall protein related to p33 is also synthesized during plant development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425691
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Studies on α-D-mannosidase and ConA during jackbean development and germination (1988)
    Springer
    Protoplasma 144 (1988), S. 34-45 
    Details
    ISSN: 1615-6102
    Keywords: ConA, α-D-mannosidase ; Immunogold labelling ; Seed cotyledons ; Legumes ; Development ; Germination ; Membrane traffic ; Targeting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Changes in the level and activity of α-D-mannosidase and ConA have been followed during a time-course of development spanning seed formation, desiccation and germination. In parallel studies, immunogold labelling has enabled these changes to be placed within a structural context of the cotyledon parenchyma cells during protein body formation, dehydration and subsequent autolysis during germination. The results indicate that the exo-glycosidase and lectin accumulate in parallel during seed formation and are packaged within the same protein bodies. Several lines of evidence suggest that the function of both proteins is related to events that occur during seed development rather than germination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01320278
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Bioelectric and biosynthetic aspects of cell polarity inAllomyces macrogynus (1988)
    Springer
    Protoplasma 146 (1988), S. 118-126 
    Details
    ISSN: 1615-6102
    Keywords: Bioelectricity ; Calcium ; Polarity ; Hyphal growth ; Allomyces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In contrast to all filamentous fungi examined to date, vegetative hyphae ofAllomyces macrogynus, whether extending or not, produced an outward flow of positive electrical current, at a maximum of 0.16 μA cm−2 around 40 μm behind the apex, as measured with a vibrating probe. Inward currents of up to 0.55 μA cm−2 were recorded around the rhizoids. Increases in outward current were observed in hyphae pre-grown under oxygen deficiency and then allowed to widen backwards to the hyphal base in sufficient oxygen. When spores were germinated in an applied electrical field they produced rhizoids predominantly towards the anode. Hyphae were produced initially towards the cathode but later bent around towards the anode. Experiments with a range of chemicals provided no evidence for the involvement of calcium in vegetative growth and development inA. macrogynus. Polyoxin and nikkomycin, inhibitors of chitin synthesis, had no effect on swimming zoospores, but inhibited wall formation of cysts, rhizoids and forward and backward growing hyphae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01405920
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Distortion of plant cell plate formation by the intracellular-calcium antagonist TMB-8 (1988)
    Springer
    Protoplasma 144 (1988), S. 92-100 
    Details
    ISSN: 1615-6102
    Keywords: Calcium ; Cell plate ; Funaria ; Phragmoplast ; TMB-8
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Caulonema tip cells ofFunaria deposit new oblique cross walls of specific morphology and placement by a highly defined reorientation mechanism. In the presence of the purported intracellular Ca2+ antagonist 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8), these cross walls form in the proper place but exhibit a distorted morphology. Video microscopy indicates that the deformation takes place during the reorientation of the cell plate from a perpendicular to an oblique configuration. Electron micrographs of TMB-8 treated cells indicate a stabilization of phragmoplast microtubules and a greater amount of vesicles and membrane in the developing cell plate. TMB-8 treated cells also show intense chlortetracycline fluorescence from mitochondria, vesicles and endoplasmic reticulum as compared to untreated cells indicating that TMB-8 is blocking release of Ca2+ from intracellular stores. It is concluded that this may cause distortation of cross walls as they form by delaying vesicle fusion, stabilizing microtubules, and increasing the amount of new wall material in the developing cell plate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01637241
    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...