ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Tributyltin (TBT) compounds, some of the most toxic xenobiotics, produce a variety of pathological reactions in animals. A reliable biomonitoring method to assess the degree of environmental TBT pollution has been described based on investigations of virilization phenomena in prosobranch snails (Mollusca: Gastropoda). Examples are the imposex phenomenon in marine and freshwater species, the intersex reaction in littorinids and the reduction of female sexual glands and offspring numbers in further species resulting mainly in a sterilization of females. The degree of imposex or intersex in populations is determined by different biomonitoring indices which allow to assess the TBT pollution of the environment at low costs with high precision. The effectiveness of TBT legislations is analysed by extensive surveys in France and Ireland indicating that there is still a continuing threat to sensitive marine organisms. TBT disturbs the biosynthesis of steroid hormones on the level of estrogen biosynthesis. The observed virilization phenomena seem due to an inhibition of the cytochrome P-450 dependent aromatase by this organotin compound.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-3017
    Keywords: Imposex ; TBT pollution ; biomonitoring ; reproduction ; Marisa cornuarietis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: The ramshorn snail Marisa cornuarietis (L., 1767) exhibits imposex (occurrence of male parts in addition to the female genital duct) under the influence of TBT (tributyltin) in laboratory experiments and accumulates this biocide in a time-and concentration-dependent manner. A comparison of BCF (bioconcentration factors) demonstrates that this limnic species accumulates more TBT than marine species. Evidence is given that TBT causes hormonal disorders which are responsible for imposex development. The testosterone/oestradiol quotient reflects the imposex development which can be described by a classification scheme differentiating four stages in Marisa cornuarietis. In the background of the constantly increasing organotin concentration in the limnic environment Marisa cornuarietis could be a well-suited bioindicator for TBT pollution. No other limnic species with a lower threshold concentration for measurable TBT effects is reported within the literature.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-5117
    Keywords: imposex ; gastropod ; TBT ; Nucella ; Ocenebra ; Hinia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A comparative study of the three gastropod species Nucella lapillus (L.), Ocenebra erinacea (L.) and Hinia (Nassarius) reticulata (L.) reveals that Nucella is the most TBT sensitive species while Hinia is the least sensitive. Of the two imposex indices VDSI and RPSI, good interspecies correlations were obtained only for VDSI. The three species can be considered as complementary not only in terms of their ecology but also for their levels of sensitivity. Indeed, Nucella and Ocenebra are useful test species at TBT concentrations below 2 ng Sn 1−1 while Hinia is the more appropriate species at higher TBT levels. For the first time, two sterilised Hinia females are recorded. This sterilization does not seem to be due to proliferation of vas deferens tissue in the vaginal opening and further investigation is needed to find intermediary VDS stages between stage 4+ and sterilization. Studies using Nucella show that the use of narcotization in imposex analysis leads to an underestimation of RPSI compared with non-narcotization methods. Indeed, narcotization straightens the penis and increases its length when compared with non-narcotized animals, but this increase is proportionally higher in males than in females.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-5117
    Keywords: Nucella lapillus ; Littorina littorea ; imposex ; intersex ; TBT effect monitoring ; geographical differences
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two different tributyltin (TBT)-induced virilisation phenomena in prosobranch snails – intersex in Littorina littorea and imposex in Nucella lapillus – are compared in order to facilitate their simultaneous use in geographical large scale effect monitoring surveys. Imposex in dogwhelks is a more sensitive biomarker and should be used in areas that are only slightly or moderately contaminated with TBT (ambient TBT concentrations 〈 2.0 ng as Sn l-1). The assessment of intersex intensities in periwinkle populations has considerable advantages in areas with higher TBT concentrations and should be used also wherever dogwhelks are absent irrespective of the TBT exposure level. The intersex index (ISI) and vas deferens sequence (VDS) index are proposed as the most suited parameters for effect monitoring purposes. The geographical uniformity of intersex and imposex is analysed and proven for the coasts of Ireland, France, and Germany. A relative loss of TBT sensitivity in females can be found, but to a varying extent in both species. The implications of this result for biological TBT effect monitoring programmes are discussed in light of the fact that intersex and imposex have both been found to be irreversible. Because it is the objective of these programmes to assess current TBT contaminations and resulting biological effects, only relatively young specimens should be considered in the sampling strategy.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-5117
    Keywords: Hydrobia ulvae ; Littorina littorea ; imposex ; intersex ; reproductive failure ; TBT biomonitoring ; TBT biomonitoring
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A short description of the imposex condition in Hydrobia ulvae is presented. In this species four different imposex stages with two types of development were identified. In laboratory experiments the mud snail accumulates TBT in a time and concentration-dependent manner. Increasing biological indices e.g. VDSI (vas deferens sequence index), female penis length (FPL) and the imposex incidence are significantly correlated with increasing TBT body burden. The percentage of sterile females depends on the TBT contamination of sediments. An interspecific comparison of the mud snail H. ulvae and the periwinkle Littorina littorea elucidates that the mud snail is the more sensitive species at lower environmental TBT concentrations.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-5117
    Keywords: Littorina littorea ; prostate gland ; histology ; intersex ; female stage 3
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the prosobranch snail Littorina littorea (L., 1758) the ultrastructure of the prostate gland cells (pgc) in males and the altered glandular epithelium of the pallial oviduct of females in intersex stage 3 is compared. Regarding form, structure, organelles and secretory products the pgc in males are identical with the corresponding gland cells of the females. Consequently these results demonstrate that in females of intersex stage 3 the epithelium of the pallial oviduct, which originally consists of several (3) glandular parts, is transformed into a male prostate gland.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1438-3888
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tributyltin (TBT) exposure at different concentrations (5, 60, and 100 ng TBT as Sn/l) induces a concentration- and time-dependent imposex (=pseudohermaphroditism) development in femaleNucella lapillus andHinia reticulata. In both species the average imposex stage, termed as vas deferens sequence (VDS) index, and the average female penis length increases with increasing TBT concentration and duration of TBT exposure. Testosterone added at a concentration of 500 ng/l induces a faster and more intensive imposex development compared to that induced by the TBT concentrations used in the present experiments. Radioimmunological determination of endogenous steroid content reveals increasing testosterone titres in female gastropods exposed to TBT which correlate with the TBT concentration used and the duration of the experiment. The most marked and highest increase of the endogenous testosterone level is exhibited by females, of both species exposed to testosterone. Simulataneous exposure to TBT and to the antiandrogen cyproterone acetate which suppresses imposex development completely inN. lapillus and reduces imposex development strongly inH. reticulata proves that the imposex-inducing effects of TBT are mediated by an increasing androgen level and are not caused directly by the organotin compound itself. Further-more, TBT-induced imposex development can be suppressed in both snails by adding estrogens to the aqueous medium. These observations suggest that TBT causes an inhibition of the cytochrome P-450 dependent aromatase system which catalyses the aromatization of androgens to estrogens. The increase of the androgen content or the shift of the androgen-estrogen balance in favour of androgens induces the development of pseudohermaphroditism in marine prosobranchs. Artificial inhibition of the cytochrome P-450 dependent aromatase system using SH 489 (1-methyl-1,4-androstadiene-3,17-dione) as a steroidal aromatase inhibitor and flavone as a nonsteroidal aromatase inhibitor induces imposex development inN. lapillus as well as inH. reticulata.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1438-3888
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The muricid gastropodOcenebra erinacea exhibits imposex (occurrence of male parts in addition to the female genital duct), a phenomenon which is caused by tributyltin (TBT)-compounds leached from ships’ antifouling paints. Five stages of imposex development (1–5) with two different types at stage 1 can be distinguished and are documented with SEM-photographs for the first time. Four additional alterations of the genital tract are shown. Close to harbours and marinas,O. erinacea females exhibit malformations of the pallial oviduct, which seem to inhibit copulation and capsule formation resulting in sterilization. The TBT accumulation in the whole body and the accumulation pattern in single tissues are described; contrary to other prosobranchs no sexrelated differences were found. The VDS, uncubed RPS and average female penis length of a population were analysed regarding their quality as parameters for TBT biomonitoring. On the background of the ecology of this species the VDS is chosen as the best index. Only in highly polluted areas should the uncubed RPS be used as a secondary parameter. A statistical study, based on the analysis of natural populations ofNucella lapillus andO. erinacea, allows a comparison of the specific TBT sensitivity of the two bioindicators. Dogwhelks exhibit a greater TBT sensitivity, namely at slightly polluted sites, nevertheless even here rough tingles develop obvious imposex characteristics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Specimens from the prosobranch Hinia reticulata collected along the coast of Brittany and Normandy from 1988 to 1991 exhibited imposex (occurrence of male parts in addition to the female genital duct) in response to tributyltin (TBT) pollution. Four stages of imposex development (1 to 4) with two different types in the Stages 1, 3 and 4 could be distinguished and have been documented with scanning electron micrographs for the first time. Furthermore, three additional alterations of the genital tract are shown. Neither TBT-induced sterilization nor sex change occurred. TBT accumulation in whole body and selected tissues is described and sex-related differences are shown. The VDS (vas deferens sequence) index, cubed and uncubed RPS (relative penis size) index and average female penis length of a population were analysed with regard to their quality as indices for TBT biomonitoring. Based on the way imposex develops in this species the VDS is recommended as the most valid index. Only in highly polluted areas should the uncubed RPS be used as a second index.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Hinia reticulata and Nucella lapillus (collected from 1989 to 1991 at Pointe de Pléneuf and Méan Mélen, France, respectively) exhibit imposex in response to tributyltin (TBT) pollution leached from antifouling paints and proved to be good TBT bioindicators. H. reticulata was kept for 18 mo under TBT-free conditions in the laboratory, but no evidence for imposex remission was found. A second series of experiments showed that food chain uptake of TBT from a contaminated diet is an important mode of TBT exposure in H. reticulata. Comparative tank experiments with H. reticulata and N. lapillus demonstrated that the same type of TBT exposure resulted in comparable TBT body burdens, biological concentration factors, and imposex development in both species [measured as increase of VDS (vas deferens sequence index), uncubed RPS (relative penis size index) and average female penis length]. Differences in imposex development of natural and laboratory populations are discussed against the background of different types of TBT contamination of their food. A statistical study, based on an analysis of natural populations of both prosobranch species, makes a comparison of the specific TBT sensitivity of the two bioindicators possible. As a consequence it is proposed that TBT biomonitoring programs in Europe should use both prosobranchs as indicator species.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...