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  • Articles  (15)
  • Triticum aestivum
  • fish
  • Springer  (15)
  • 1995-1999  (15)
  • Chemistry and Pharmacology  (15)
  • 1
    Electronic Resource
    Electronic Resource
    Comparative study of DNA adducts levels in white sucker fish (Catostomus commersoni) from the basin of the St. Lawrence River (Canada) (1995)
    Springer
    Molecular and cellular biochemistry 148 (1995), S. 133-138 
    Details
    ISSN: 1573-4919
    Keywords: DNA adducts ; liver ; fish ; 32P-postlabelling ; polycyclic aromatic hydrocarbons ; genotoxic biomarker
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The levels of DNA adducts in the hepatic tissue of the white sucker fish speciesCatostomus commersoni were determined by32P-postlabelling. The fish were caught at four sites: two sites near the city of Windsor (Québec, Canada) on the St. François River, a downstream tributary of the St. Lawrence River, and two sites in the St. Lawrence River itself, near the city of Montréal (Québec, Canada). The latter sites are known to be contaminated by many pollutants including polycyclic aromatic hydrocarbons. Total adduct levels in all fish ranged from 25.1–178.0 adducts per 109 nucleotides. White sucker from the selected sites of the St. Lawrence River had a significantly higher mean level of DNA adducts than those of the St. François River (129.4 vs 56.8, respectively). These results suggest that the effluents of many heavy industries (e.g. from a Soderberg aluminium plant) flowing in the St. Lawrence River are more likely to produce genotoxic damage to fish than those released in one of its tributary, and mainly associated to the activities of a small town and a nearby pulp and paper mill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00928150
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  • 2
    Electronic Resource
    Electronic Resource
    Are Tropical Herbivores More Resistant Than Temperate Herbivores to Seaweed Chemical Defenses? Diterpenoid Metobolites from Dictyota acutiloba as Feeding Deterrents for Tropical Versus Temperate Fishes and Urchins (1997)
    Springer
    Journal of chemical ecology 23 (1997), S. 289-302 
    Details
    ISSN: 1573-1561
    Keywords: Acutilol diterpenes ; biogeography ; chemical defenses ; Dictyota ; diffuse coevolution ; fish ; plant–herbivore interactions ; sea urchin ; secondary metabolites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Because herbivory is more intense in the tropics, tropical seaweeds may be better defended against herbivory than are temperate seaweeds. A “diffuse” coevolutionary corollary to this hypothesis is that tropical herbivores should be more resistant to seaweed defenses than temperate herbivores because tropical herbivores more commonly encounter heavily defended seaweeds. We begin to test the latter prediction using three newly discovered diterpenoid secondary metabolites from the tropical brown alga Dictyota acutiloba. We tested the feeding deterrent properties of these compounds against common herbivorous fishes and sea urchins from warm-temperate North Carolina versus tropical Guam using standardized laboratory feeding assays. The temperate herbivores were deterred by lower concentrations of secondary metabolites than the tropical herbivores. In no case was a tropical herbivore more deterred by a compound than a temperate herbivore, suggesting that temperate herbivores may be more strongly affected by seaweed chemical defenses. Feeding by the temperate pinfish Lagodon rhomboides was significantly reduced by two of the three diterpenes at a concentration that was only 13–18% of the natural concentration found in the alga. Feeding by four species of tropical fishes (two parrotfishes and two surgeonfishes) was unaffected by metabolite concentrations that deterred the temperate fish. At 100% of natural concentrations, only one of the three compounds deterred the two parrotfishes, and none of the three compounds deterred the surgeonfishes. Contrasts between the temperate sea urchin Arbacia punctulata and the tropical sea urchin Diadema savignyi showed a similar pattern; low concentrations of acutilol A acetate strongly deterred the temperate, but not the tropical, urchin. Tropical herbivores appear more resistant than temperate herbivores to seaweed chemical defenses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/B:JOEC.0000006360.36833.13
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  • 3
    Electronic Resource
    Electronic Resource
    Different Carotenoids and Potential Information Content of Red Coloration of Male Three-Spined Stickleback (1998)
    Springer
    Journal of chemical ecology 24 (1998), S. 787-801 
    Details
    ISSN: 1573-1561
    Keywords: Breeding coloration ; Gasterosteus aculeatus ; stickleback ; fish ; multiple ornaments ; signalling ; carotenoids ; astaxanthin ; tunaxanthin ; lutein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Female sticklebacks (Gasterosteus aculeatus) use the red coloration of males as a criterion for mate choice. Redder males are more attractive. However, males often differ not only in the intensity of their coloration (from dull to bright red) but also in color quality (from yellowish to purple-red). We investigated whether the red coloration of the stickleback is actually a multiple signal made by several pigments. We kept wild caught males singly in tanks until they had built a nest and were ready to accept females. Then, we took standard photographs and measured their colors by spectrometer analyses of the slides and by descriptions of human observers. These two measurements were highly correlated. When analyzing the carotenoid content of the sticklebacks' skin we found two groups of carotenoids (astaxanthin and tunaxanthin/lutein) that were quantified for each individual. The differences in color observed in the fish are correlated to this pigment quantification. Redder fish have more astaxanthin in their skin than yellowish fish, while the color of the yellowish fish appears to be made by tunaxanthin/lutein. Our results suggest that the red coloration of sticklebacks is a multiple trait that is made of at least two different carotenoids. This opens the possibility that male sticklebacks signal more detailed information to females than a one-dimensional trait would allow.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022365315836
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  • 4
    Electronic Resource
    Electronic Resource
    Learning and sibling odor preference in juvenile arctic char,Salvelinus alpinus (L.) (1996)
    Springer
    Journal of chemical ecology 22 (1996), S. 773-786 
    Details
    ISSN: 1573-1561
    Keywords: Arctic char ; attraction ; fish ; fluviarium ; kinship ; odor ; salmonids ; Salvelinus alpinus ; siblings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The importance of learning for sibling odor preference in juvenile Arctic char was analyzed in the present study. Fish were reared in the following eight conditions: (1) communally with siblings for 15 months; (2) communally with siblings for 17 months; (3) in isolation since fertilization; (4) in isolation since fertilization and exposed to sibling scent during the whole rearing period; (5) in isolation since fertilization and exposed to sibling scent from time of free swimming; (6) in isolation since fertilization and exposed to sibling scent during the whole rearing period, except two months without scent until testing; (7) in isolation since fertilization and exposed to sibling scent from time of free swimming, except two months without scent until testing; and (8) communally with siblings followed by a two-month isolation until testing. Char were followed individually in a Y-maze (fluviarium test) with a video-computer-based image analysis system for 12 hr. Sibling-scented water was supplied to one lateral half of the test area and water from non-siblings on the opposite half. Isolated individuals without any preexposure to siblings showed no significant preference. Test fish reared with siblings and those that had been reared in isolation but exposed to sibling scent until testing preferred water conditioned by their own siblings. Isolated fish that had been exposed to sibling scent since fertilization, or since free swimming, followed by a two-month period with only pure water, showed no significant preference. Char isolated for two months after being communally reared preferred water scented by siblings. The results demonstrated that behavioral discrimination between siblings and nonsibling odors occurred after total isolation (isolated both from siblings and sibling odors) only in individuals that had been communally reared. This may suggest that social interactions are important for learning and long-term memory of sibling odors in Arctic char.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02033585
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  • 5
    Electronic Resource
    Electronic Resource
    Effect of Previous Exposure to Hydroxamic Acids in Probing Behavior of Aphid Sitobion fragariae on Wheat Seedlings (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 771-779 
    Details
    ISSN: 1573-1561
    Keywords: Aphid ; experience ; probing behavior ; sieve elements ; salivation ; cell punctures ; hydroxamic acids ; EPG ; Sitobion fragariae ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We hypothesized that aphids after previous exposure to hydroxamic acids (Hx), a family of secondary plant compounds deleterious to aphids, are able to reduce their subsequent exposure to them. This hypothesis was tested by evaluating the time to produce salivation into a sieve element (SSE) by the aphid Sitobion fragariae on seedlings of two wheat cultivars of Triticum aestivum differing in their concentration of Hx. The total time to produce a first SSE was significantly longer in the high-Hx cultivar; however, the subsequent, second SSE (first SSE after interruption of probing) in this cultivar was significantly reduced, reaching the level observed in the low-Hx plants. Therefore, a strategy to reduce the exposure to secondary compounds was observed only in the second SSE in high-Hx plants. When the experimental plant was replaced by a new unattacked plant after the first SSE, aphids did not change the behavior described, thus excluding an aphid-induced plant susceptibility. The number of cell punctures and accumulated duration was not affected by previous exposure to Hx, either in low or high Hx cultivars. Total time and pathway time but not cell punctures, seem to be the variables affected by previous exposure to Hx.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020836515674
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  • 6
    Electronic Resource
    Electronic Resource
    Differential Scanning Calorimetric Investigations on Pyloric Caeca During Ripening of Salted Herring Products (1999)
    Springer
    Journal of thermal analysis and calorimetry 57 (1999), S. 283-291 
    Details
    ISSN: 1572-8943
    Keywords: DSC ; fish ; general proteolytic activity ; pyloric caeca ; ripening ; salted herring product
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The thermoanalytical behaviour of pyloric caeca during salting and ripening was investigated using a Perkin Elmer DSC 7. Not only the thermal stability of the muscle proteins was influenced by salting but also that of pyloric caeca. It was recognised that the salting itself leads to a remarkable increase of the transition temperature compared with raw herring. An influence of the salt:fish ratio could be observed. The higher the salt content the higher the increase of the denaturation temperature. During ripening the transition temperature remained on a high level or showed only a slight decrease during the investigation period. The dependency from the salt content remained evident. The increase of the transition temperature was accompanied by a decrease of the transition enthalpy. The increase of thermal stability is connected with a decrease of the general proteolytic activity in pyloric caeca. Possibly, the enzymes are diffusing from the pyloric caeca into the muscle and cause there an increase of enzymatic activity observable in North Sea herring accompanied by a decrease of activity in pyloric caeca itself. Simultaneous the thermal stability of pyloric caeca is lowered. The reason for the differences in ripening could be seen in some enzyme-inhibiting factors unknown until now.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1010101910394
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  • 7
    Electronic Resource
    Electronic Resource
    Accumulation of mercury in estuarine food chains (1998)
    Springer
    Biogeochemistry 40 (1998), S. 235-247 
    Details
    ISSN: 1573-515X
    Keywords: fish ; invertebrates ; ligands ; mercury ; methylmercury ; phytoplankton
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract To understand the accumulation of inorganic mercury and methylmercury at the base of the estuarine food chain, phytoplankton (Thalassiosira weissflogii) uptake and mercury speciation experiments were conducted. Complexation of methylmercury as methylmercury-bisulfide decreased the phytoplankton uptake rate while the uptake rate of the methylmercury-cysteine and -thiourea complexes increased with increasing complexation by these ligands. Furthermore, our results indicated that while different ligands influenced inorganic mercury/methylmercury uptake by phytoplankton cells, the ligand complex had no major influence on either where the mercury was sequestered within the phytoplankton cell nor the assimilation efficiency of the mercury by copepods. The assimilation efficiency of inorganic mercury/methylmercury by copepods and amphipods feeding on algal cells was compared and both organisms assimilated methylmercury much more efficiently; the relative assimilation efficiency of methylmercury to inorganic mercury was 2.0 for copepods and 2.8 for amphipods. The relative assimilation is somewhat concentration dependent as experiments showed that as exposure concentration increased, a greater percentage of methylmercury was found in the cytoplasm of phytoplankton cells, resulting in a higher concentration in the copepods feeding on these cells. Additionally, food quality influenced assimilation by invertebrates. During decay of a T. weissflogii culture, which served as food for the invertebrates, copepods were increasingly less able to assimilate the methylmercury from the food, while even at advanced stages of decay, amphipods were able to assimilate mercury from their food to a high degree. Finally, fish feeding on copepods assimilated methylmercury more efficiently than inorganic mercury owing to the larger fraction of methylmercury found in the soft tissues of the copepods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005959211768
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  • 8
    Electronic Resource
    Electronic Resource
    Temperature, growth and dietary effects on fish mercury dynamics in two Ontario lakes (1998)
    Springer
    Biogeochemistry 40 (1998), S. 175-187 
    Details
    ISSN: 1573-515X
    Keywords: bioenergetics ; fish ; mercury ; methylmercury ; models
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract A bioenergetics-based model was used to investigate the effects of temperature, growth and dietary exposure on methylmercury dynamics in walleye (Stizostedion vitreum) and yellow perch (Perca flavescens) from two lakes sampled in northwestern Ontario. Orange Lake was smaller, warmer, had slower fish growth and higher mercury concentrations in yearling yellow perch and walleye (three fold difference in 40 cm walleye) than Trout Lake. The model was applied to test the hypothesis that higher water temperatures in Orange Lake increased metabolic needs, food consumption and mercury uptake in fish. The effects of different growths rates in the lakes were also considered. Temperature/metabolic effects and growth effects on internal methylmercury dynamics in walleye and perch were predicted to occur but be of secondary importance. Different dietary exposure to methylmercury was likely the dominant source of variation in fish mercury concentrations between the two lakes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005986505407
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  • 9
    Electronic Resource
    Electronic Resource
    The use of polynomial regression analysis with indicator variables for interpretation of mercury in fish data (1998)
    Springer
    Biogeochemistry 40 (1998), S. 189-201 
    Details
    ISSN: 1573-515X
    Keywords: binary variables ; fish ; impoundment ; indicator variables ; James Bay ; mercury ; polynomial regression ; Québec ; reservoirs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Mercury levels in fish in reservoirs and natural lakes have been monitored on a regular basis since 1978 at the La Grande hydroelectric complex located in the James Bay region of Québec, Canada. The main analytical tools historically used were analysis of covariance (ANCOVA), linear regression of the mercury-to-length relationship and Student-Newman-Keuls (SNK) multiple comparisons of mean mercury levels. Inadequacy of linear regression (mercury-to-length relationships are often curvilinear) and difficulties in comparing mean mercury levels when regressions differ lead us to use polynomial regression with indicator variables. For comparisons between years, polynomial regression models relate mercury levels to length (L), length squared (L2), binary (dummy) indicator variables (Bn), each representing a sampled year, and the products of each of these explanatory variables (L × B1, L2 × B1, L × B2, etc.). Optimal transformations of the mercury levels (for normality and homogeneity) were found by the Box-Cox procedure. The models so obtained formed a partially nested series corresponding to four situations: (a) all years are well represented by a single polynomial model; (b) the year-models are of the same shape, but the means may differ; (c) the means are the same, but the year-models differ in shape; (d) both the means and shapes may differ among years. Since year-specific models came from the general one, rigorous statistical comparisons are possible between models. Polynomial regression with indicator variables allows rigorous statistical comparisons of mercury-to-length relationships among years, even when the shape of the relationships differ. It is simple to obtain accurate estimates of mercury levels at standardized length, and multiple comparisons of these estimations are simple to perform. The method can also be applied to spatial analysis (comparison of sampling stations), or to the comparison of different biological forms of the same species (dwarf and normal lake whitefish).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005997430906
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  • 10
    Electronic Resource
    Electronic Resource
    Fish mercury levels in relation to characteristics of hydroelectric reservoirs in Newfoundland, Canada (1998)
    Springer
    Biogeochemistry 40 (1998), S. 217-233 
    Details
    ISSN: 1573-515X
    Keywords: Canada ; fish ; hydroelectric reservoirs ; mercury ; Newfoundland ; return time
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Mercury levels in fish have been demonstrated to increase after impoundment with augmented levels of mercury predicted to decline as the reservoir ages. Previous research in Newfoundland predicted return rates in the order of 10 to 12 years for landlocked Atlantic salmon or ouananiche (Salmo salar) and 7 years for brook trout (Salvelinus fontinalis). In order to test the validity of these predictions on a broader spatial and temporal scale, and develop more generally predictive ‘models’, mercury levels in three fish species were studied in 16 older Newfoundland hydroelectric reservoirs of various age (32 to 95 years) and area flooded (21 to 13,000 ha). Mercury concentrations were standardized to fish length and correlated with physical, chemical, and biological characteristics of the sampling sites. Standard length mercury levels ranged from 0.23 to 0.86 ppm in ouananiche, 0.13 to 0.59 ppm in brook trout, and 0.22 to 0.72 in arctic charr (Salvelinus alpinus). Fish in excess of the Canadian Safety Limit (0.5 ppm) were collected from 14 of 16 sites for ouananiche, 8 of 17 sites for brook trout, and 3 of 7 sites for arctic charr, including control lakes. Standard length fish mercury levels were correlated with reservoir age and (log10) area flooded for ouananiche and with pH for arctic charr. A multiple regression model was developed relating standard length mercury in ouananiche with reservoir age and log10 of the flooded area. There were no apparent relationship between reservoir characteristics and brook trout mercury concentrations. Based on this analysis, it is not possible, at present, to develop generally predictive models for all species found in Newfoundland impoundments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005975714493
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  • 11
    Electronic Resource
    Electronic Resource
    Design and synthesis of potent tyr(OMe)5-gonadotropin-releasing hormone (GnRH) analogues with modifications at positions 6, 9 and 10 (1998)
    Springer
    International journal of peptide research and therapeutics 5 (1998), S. 305-315 
    Details
    ISSN: 1573-3904
    Keywords: fish ; gonadotropin release ; Gonadotropin-Releasing Hormone (GnRH) ; peptide analogues ; receptor binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary We have recently reported the synthesis and the conformational properties of some Gonadotropin-releasing hormone (GnRH) analogues in which the tyrosine residue at position 5 is substituted with tyrosine-O-methyl (Keramida et al., Let. Pept. Sci., 3 (1996) 257/Matsoukas et al., Eur. J. Med. Chem., 32 (1997) 927). The analogue [Tyr-(OMe)5]-GnRH was found to exert a lower degree of desensitization than the native GnRH peptides in terms of pituitary gonadotropin (GTH) release in goldfish. Compared to GnRH, however, [Tyr-(OMe)5]-GnRH exerted a lower GTH-release potency in cultured goldfish pituitary fragments, and was bound with a lower binding affinity to the rat pituitary GnRH receptors. In order to increase the potency of [Tyr-(OMe)5]-GnRH, we have synthesized a group of GnRH peptides containing Tyr-(OMe)5 in combination with other substitutions at positions 6, 9 and 10 and we have estimated their binding affinity for the rat pituitary receptors and gonadotropin (GTH) release potency in the goldfish pituitary. A selected number of these analogues was also tested for their ability to induce ovulation in seabass. The important structural modifications that increased the binding and gonadotropic activity of [Tyr(OMe)5]-GnRH in vitro and in vivo were found to include the replacement of the proline at position 9 with azetidine, glycine amide terminus with an alkyl amide group and Gly6 residue with hydrophilicd-amino acids such asd-Arg6. Overall, the findings provide SAR information on a group of novel GnRH peptides that can be also used to induce ovulation in teleosts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02443548
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  • 12
    Electronic Resource
    Electronic Resource
    Design and Synthesis of Potent Tyr(OMe)5-Gonadotropin-Releasing Hormone (GnRH) Analogues with Modifications at Positions 6, 9 and 10 (1998)
    Springer
    International journal of peptide research and therapeutics 5 (1998), S. 305-315 
    Details
    ISSN: 1573-3904
    Keywords: fish ; gonadotropin release ; Gonadotropin-Releasing Hormone (GnRH) ; peptide analogues ; receptor binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract We have recently reported the synthesis and the conformational properties of some Gonadotropin-releasing hormone (GnRH) analogues in which the tyrosine residue at position 5 is substituted with tyrosine-O-methyl (Keramida et al., Let. Pept. Sci., 3 (1996) 257/Matsoukas et al., Eur. J. Med. Chem., 32 (1997) 927). The analogue [Tyr-(OMe)5]-GnRH was found to exert a lower degree of desensitization than the native GnRH peptides in terms of pituitary gonadotropin (GTH) release in goldfish. Compared to GnRH, however, [Tyr-(OMe)5]-GnRH exerted a lower GTH-release potency in cultured goldfish pituitary fragments, and was bound with a lower binding affinity to the rat pituitary GnRH receptors. In order to increase the potency of [Tyr-(OMe)5]-GnRH, we have synthesized a group of GnRH peptides containing Tyr-(OMe)5 in combination with other substitutions at positions 6, 9 and 10 and we have estimated their binding affinity for the rat pituitary receptors and gonadotropin (GTH) release potency in the goldfish pituitary. A selected number of these analogues was also tested for their ability to induce ovulation in seabass. The important structural modifications that increased the binding and gonadotropic activity of [Tyr(OMe)5]-GnRH in vitro and in vivo were found to include the replacement of the proline at position 9 with azetidine, glycine amide terminus with an alkyl amide group and Gly6 residue with hydrophilic D-amino acids such as D-Arg6. Overall, the findings provide SAR information on a group of novel GnRH peptides that can be also used to induce ovulation in teleosts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008885522753
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  • 13
    Electronic Resource
    Electronic Resource
    Lectin like properties and differential sugar binding characteristics of C-reactive proteins purified from sera of normal and pollutant induced Labeo rohita (1999)
    Springer
    Glycoconjugate journal 16 (1999), S. 741-750 
    Details
    ISSN: 1573-4986
    Keywords: C-reactive protein ; pollutant ; agglutinin ; galactose binding lectin ; fish ; Labeo rohita
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Different forms of C-reactive proteins (CRPs) have been purified to electrophoretic homogeneity from the sera of Labeo rohita confined in freshwater (CRPN) and water polluted with nonlethal doses of cadmium (CRPCd) or mercury (CRPHg). CRPN[emsp4 ], CRPCd[emsp4 ], and CRPHg show remarkable differences in their electrophoretic mobility but exhibit strong immunological cross reactivity. All these CRPs exhibit variable agglutination properties with erythrocytes from diverse sources in presence of Ca+2, which could be inhibited by a variety of sugars showing specificity for galactose. Inhibition results show that the potency of galactose as an inhibitor increases about 4 fold in the process of transformation of CRPN to CRPCd and CRPHg[emsp4 ]. In case of CRPN[emsp4 ], Gal β(1→1) Gal and oNO2 phenyl β-Gal show highest inhibitory potency while oNO2-phenyl β-Gal is the most potent inhibitor for CRPCd and CRPHg but the potency of Gal β(1→1) Gal reduced drastically. 6-phosphate D-Gal and stachyose are 20 times weaker inhibitors than D-Gal for induced CRP mediated agglutination, in contrast, these sugars are only 6 times weaker for CRPN[emsp4 ]. Dissociation constants of the binding of CRPN with phosphoryl choline (PC) and galactose are about 9[emsp4 ]mM and PC binding causes a change in the α and β conformations of these CRPs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007167611778
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  • 14
    Electronic Resource
    Electronic Resource
    Comparison of open and closed focussed microwave digestions in view of total mercury determination by cold vapour atomic absorption spectrometry (1995)
    Springer
    Microchimica acta 119 (1995), S. 199-209 
    Details
    ISSN: 1436-5073
    Keywords: microwave digestion ; fish ; mercury ; CVAAS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Food samples digestion, in view to quantify total mercury, is the first step to perform before measuring mercury by cold vapour atomic absorption spectrometry (CVAAS). We have compared two microwave digestion systems, one working at atmospheric pressure (open system) and the other one under pressure (closed system). Results obtained for fish muscle samples by the two methods are in good agreement. However, fat is not digested in the open system, whereas in the closed system no more fat remains in the final solution. During the quantification step, applying the CVAAS technique, we have noticed that the choice and the concentration of the reductant solution is very important to obtain good results. Elaborated methods have been validated using certified reference materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01243999
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  • 15
    Electronic Resource
    Electronic Resource
    Critical comparison of methods for mercury determination in fish (1995)
    Springer
    Microchimica acta 119 (1995), S. 305-310 
    Details
    ISSN: 1436-5073
    Keywords: mercury ; fish ; collaborative study ; atomic absorption spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract One of the major analytical problem in the analysis of fish tissues for total mercury is the dissolution of the sample. This paper compares two different methods of wet digestion (microwave and closed pressurized vessel), followed by FIAAS as final determination and a Zeeman-solid-sample-AAS determination method without previous mineralization. Six fish samples were selected for this study. The top, the central and the bottom portions of the fish were analyzed separately. The mercury contents in the bottom portions determined by Zeeman-solid-sample-AAS were significantly higher than those obtained by the other two systems. A good correlation was observed among the results of the different techniques.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01244010
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