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51.
Palace VP Allen-Gil SM Brown SB Evans RE Metner DA Landers DH Curtis LR Klaverkamp JF Baron CL Lockhart WL 《Chemosphere》2001,45(2):185-193
Induction of phase I biotransformation enzymes is recognized as a hallmark response in fish exposed to coplanar PCBs. Depletions of vitamins A and E and disrupted thyroid hormone and glandular structure secondary to this induction have not yet been examined in an arctic fish species. Arctic grayling were exposed to a single oral dose of 0 (control), 10, 100 or 1000 ng 3,3',4,4'-tetrachlorobiphenyl (TCB) g(-1) bodyweight, a contaminant found in most arctic fish. After 30 and 90 days of exposure, TCB concentrations in tissues, hepatic phase I activity (as ethoxyresorufin-O-deethylase (EROD)), plasma and tissue vitamin A and E concentrations, plasma thyroid hormone levels and thyroid glandular structure were examined. Total plasma osmolality, as an indicator of overall fish health was also monitored. TCB recovery in tissues was low and extremely variable, making comparisons between intended dose groups inappropriate. Therefore, correlation analysis between actual recovered TCB concentrations and biochemical responses was employed. Hepatic EROD activity correlated strongly with liver TCB concentrations. Liver concentrations of vitamin A were altered as a function of TCB concentrations and EROD activity, but plasma vitamin A status was not affected. Vitamin E was depleted by TCB accumulation in blood and EROD induction in liver of males only at 90 days postexposure. Thyroid hormones status and glandular structure were not affected by the short duration TCB exposures used in this experiment. TCB concentrations were correlated with an elevation in plasma osmolality. Results from this experiment indicate that the vitamin status and osmoregulation of arctic grayling exposed to TCB can be compromised. Further studies of field populations exposed to this type of contaminant are warranted. 相似文献
52.
Alstad NE Kjelsberg BM Vøllestad LA Lydersen E Poléo AB 《Environmental pollution (Barking, Essex : 1987)》2005,133(2):333-342
The toxicity of aluminium to fish is related to interactions between aluminium and the gill surface. We investigated the possible effect of water ionic strength on this interaction. The mortality of brown trout (Salmo trutta L.) exposed to three different degrees of Al polymerisation was compared in water with increased ionic strength (mean 7.31 x 10(-4) M) after additions of the base cations Ca2+, Mg2+, Na+ or K+, and in water with no such addition (mean ionic strength 5.58 x 10(-4) M). Only a very slight ameliorating effect of increased ionic strength was observed, while the degree of Al polymerisation was of major importance in fish mortality. In addition, it was observed that smaller fish survived the Al exposures for a longer time than larger fish. We hypothesise that this is because larger fish are more susceptible to hypoxia than smaller fish. 相似文献
53.
Sapozhnikova Y Zubcov N Hungerford S Roy LA Boicenco N Zubcov E Schlenk D 《Chemosphere》2005,60(2):196-205
The Dniester River is one of the largest rivers in Eastern Europe and receives input from numerous anthropogenic activities. In October 2001, fish samples (Abramis brama, Rutilus rutilus heckeli, Perca fluviatilis, Chondrostoma nasus, Carassius auratus gibelio, and Cyprinus carpio) were collected and analyzed for metals and various pesticides. Maximum total DDT pesticide concentrations were between 27.7 and 34.2 ng/g wet weight in muscles and gonads, respectively. DDE isomers comprised up to 70% of total DDT measurement in fish tissues, indicating historical rather than recent DDT pollution. Chlordane and lindane were also detected in amounts up to 37 and 76 ng/g wet weight in gonads, respectively. Among organophosphorous pesticides, malathion showed extremely high concentrations--3 microg/g wet weight in muscles and 46 microg/g wet weight in gonads, indicating recent exposure. Copper concentrations in muscles (1.8-7.2 microg/g) exceeded Threshold Effect Concentrations for copper in fish. Detection of high concentrations of malathion and copper in fish tissues indicated potential anthropogenic stress for more sensitive aquatic biota, likely from agricultural sources in the Dniester River. 相似文献
54.
Summary. Allopatric populations of the leaf beetle Chrysomela lapponica are known to feed upon either willow (Salicaceae) or birch (Betulaceae). This study aimed to elucidate the differentiation
process of these allopatric populations. We investigated whether these allopatric populations specialized on different host
plants are still able to produce fertile offspring when interbreeding. Individuals from a population in Finland (willow specialists)
and one in the Czech Republic (birch specialists) were crossed in laboratory. Hybrid formation succeeded only between females
from the Czech, birch specialized population and males from the Finnish, willow specialized population, while no eggs were
produced by females of the willow specialists having mated males of the birch specialists. Behavioral, morphological, physiological,
and chemical features of the F1 hybrids were studied. The chemical composition of larval defensive secretion and feeding preferences of the resulting F1 hybrids mainly showed similarities with the paternal phenotype, while the area of black coloring on the offspring’s elytra
was intermediate between those of the parental elytra. F1 hybrids did not accept the host plant (birch) of their mothers for feeding and only survived on willow. Thus, since mothers
only lay eggs on birch, we found evidence for a postzygotic isolation mechanism between the individuals of the two investigated
populations: when having been mated with willow specialized Finnish males, the birch specialized Czech mothers place the hybrid
eggs on a plant species (birch), on which the hatching larvae cannot survive. 相似文献
55.
Fleur E. Champion de Crespigny Nina Wedell 《Behavioral ecology and sociobiology》2007,61(8):1229-1235
The maternally inherited bacterium Wolbachia pipientis generates strong reproductive incompatibilities between uninfected females and infected males (cytoplasmic incompatibility),
significantly reducing both female and male reproductive success. Such fitness costs are thought to place selective pressure
on hosts to evolve pre-copulatory preferences for mating with compatible mates, thereby enabling them to avoid the reproductive
incompatibilities associated with Wolbachia. Therefore, uninfected females are predicted to prefer mating with uninfected males, whereas infected males are predicted
to prefer mating with infected females. Despite these predictions, previous investigations of pre-copulatory mate preferences
in Wolbachia-manipulated Drosophila have not found evidence of female preference for uninfected or compatible males. However, none of these studies utilised
a design where focal individuals are provided with a simple choice in a relatively non-competitive situation. We examined
both female and male pre-copulatory mate preference based on mate infection status in Drosophila simulans and D. melanogaster using simple choice assays involving between 30–50 replicates per treatment. Although we found no evidence of female pre-copulatory
mate preferences in either species, male D. simulans exhibited some preference for mating with females of the same infection status. However, this preference was not evident
when we repeated the experiment to confirm this finding. Consequently, we conclude that neither male nor female D. melanogaster and D. simulans exhibit significant Wolbachia-associated pre-copulatory mate preferences. 相似文献
56.
Harriet von Koskull Ph.D. Annukka Ritvanen Pirkko Ämmälä Nina Gahmberg Riitta Salonen 《黑龙江环境通报》1989,9(6):433-437
Trisomy 12 mosaicism (44 per cent) was detected prenatally in cultured amniocytes. A cordocentesis was performed to confirm the result. Only normal cells were found in the fetal blood sample. The fetus was estimated to be at a low risk of having a chromosomal abnormality and the pregnancy continued. Eight days after birth, a congenital heart defect was detected in the child. Several dysmorphic features were also evident. Further karyotyping of different tissues revealed normal blood and urinary cells but trisomic cells in the placenta (100 per cent) and in skin fibroblasts (25 per cent). The child died at 5 weeks of age. In this case, the fetal blood sample failed to reveal the real chromosome constitution of the fetus. 相似文献
57.
Different types of fetal nucleated cells can be found in maternal blood, providing the possibility of non-invasive prenatal diagnosis. For this purpose, we have studied fetal erythroblasts. We discovered that haemoglobin-containing cells treated with 2,3-bisphosphoglycerate (BPG) can be visualized by a peroxidase reaction, which at the same time visualizes an in situ hybridization (ISH) signal, specific for the X, Y or 21 chromosome. In order to prove that the BPG-positive cells were erythroid, an anti-glycophorin A (GPA) antiserum combined with a staphylococcal rosette technique was used. To enrich for erythroblasts, leukocytes were depleted from maternal blood by treatment with anti-CD45 monoclonal antibody and passage over an anti-mouse IgG-coated glass bead column. To evaluate the potential of the method for clinical use, we studied maternal blood samples from 18 women referred to us for prenatal diagnosis between 6 and 19 weeks of gestation. Erythroblasts were found in 13 out of 14 normal pregnancies. Erythroblasts with a Y-signal were found as early as 9 weeks of gestation, but at 6 weeks the Y-signal was seen in BPG-negative cells only. These cells showed an epithelioid morphology indicating that they were cytotrophoblasts. The BPG-ISH method provides a simple technique for identifying erythroblasts and simultaneously visualizing a desired probe. 相似文献
58.
Nina Kaminen-Ahola 《黑龙江环境通报》2020,40(9):1185-1192
Fetal alcohol spectrum disorders (FASD) are a consequence of prenatal alcohol exposure (PAE). The etiology of the complex FASD phenotype with growth deficit, birth defects, and neurodevelopmental impairments is under extensive research. Both genetic and environmental factors contribute to the wide phenotype: chromosomal rearrangements, risk and protective alleles, environmental-induced epigenetic alterations as well as gene-environment interactions are all involved. Understanding the molecular mechanisms of PAE can provide tools for prevention or intervention of the alcohol-induced developmental disorders in the future. By revealing the alcohol-induced genetic and epigenetic alterations which associate with the variable FASD phenotypes, it is possible to identify biomarkers for the disorder. This would enable early diagnoses and personalized support for development of the affected child. 相似文献
59.
Nina Peuhkuri 《Behavioral ecology and sociobiology》1999,46(5):307-312
Similarity among group members may serve as a defence against visually hunting predators that preferentially attack individuals
who are phenotypically different from the group majority. The presence of such odd individuals in an otherwise homogeneous
group may, however, increase the vulnerability of the other group members as well. Individuals might thus be expected to form
uniform groups in order to decrease predation risk, not only in trying to avoid being odd in a group, but also when attempting
to avoid being accompanied by odd individuals. This hypothesis was tested with small and large three-spined sticklebacks,
Gasterosteus aculeatus. Focal fish were offered the choice between a shoal consisting of conspecifics that were all similar in body length to the
focal fish (matching shoal) and a shoal in which one or a few individuals differed in body length from the focal fish (non-matching
shoal). In the control experiment, all individuals in the non-matching shoal differed in size from the focal fish. The control
confirmed that individuals preferably joined the matching shoal when the alternative option was to be odd in another one.
However, when the alternative for size-assortative shoaling was to belong to the majority in a mixed shoal, the shoal choice
of individuals appeared on average to be random. Visual contact with a live pike, Esox lucius, did not affect the shoal choice pattern. Furthermore, despite the frequency-dependent nature of the oddity effect, varying
the number of odd individuals in the non-matching shoal did not have a significant effect on individual's shoaling decisions.
These results suggest that size-assortativeness in fish shoals is not a result of individuals avoiding being among the majority
in a mixed group.
Received: 2 September 1998 / Received in revised form: 12 May 1999 / Accepted: 29 May 1999 相似文献
60.
Céline Dupont Francesca Romana Grati Kwong Wai Choy Sylvie Jaillard Jérôme Toutain Marie-Laure Maurin Jose Antonio Martínez-Conejero Claire Beneteau Aurélie Coussement Denise Molina-Gomes Nina Horelli-Kuitunen Azzedine Aboura Anne-Claude Tabet Justine Besseau-Ayasse Bettina Bessieres-Grattagliano Giuseppe Simoni Gustavo Ayala Brigitte Benzacken François Vialard 《黑龙江环境通报》2015,35(1):35-43