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Ronny Blust - One of the best experts on this subject based on the ideXlab platform.

Thierry Backeljau - One of the best experts on this subject based on the ideXlab platform.

H De Wolf - One of the best experts on this subject based on the ideXlab platform.

B. Bauer - One of the best experts on this subject based on the ideXlab platform.

  • Ultrastructure of prostate gland tissue in males and females with intersex phenomena of Littorina littorea L.
    Aspects of Littorinid Biology, 1998
    Co-Authors: G. Sundermann, B. Bauer, Jörg Oehlmann
    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.

  • Toxico-kinetic and -dynamic aspects of TBT-induced imposex in Hydrobia ulvae compared with intersex in Littorina littorea (Gastropoda, Prosobranchia)
    Aspects of Littorinid Biology, 1998
    Co-Authors: Ulrike Schulte-oehlmann, P Fioroni, B. Bauer, Jörg Oehlmann, U.-s. Leffler
    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.

  • the use of Littorina littorea for tributyltin tbt effect monitoring results from the german tbt survey 1994 1995 and laboratory experiments
    Environmental Pollution, 1997
    Co-Authors: B. Bauer, P Fioroni, U Schulteoehlmann, Jörg Oehlmann, W Kalbfus
    Abstract:

    Field investigations and laboratory experiments were performed to test the applicability of the intersex phenomenon in Littorina littorea for biological TBT-effect monitoring and to give further insights into toxicological aspects of intersex development. The intensity of the phenomenon is correlated with the degree of TBT contamination in the environment. Statistically highly significant correlations of biological indices and TBT concentrations in tissue and sediment exist. Intersex can be induced only in juvenile and sexually immature females and its intensity depends on the ontogenetic stage of development during TBT exposure. For the first time, malformations in male periwinkles closely related to the TBT contamination can be described; the reduction of male mamilliform penial glands shows highly significant correlations to TBT concentrations in tissues. The intersex phenomenon in Littorina littorea is proposed for a biological TBT-effect monitoring in those areas where the dogwhelk Nucella lapillus, as the more sensitive species in European surveys, is absent. The intersex index (ISI) as the mean value of the intersex stages in a sample should be used as the most sensitive biological parameter for the assessment of the TBT contamination in Littorina littorea.

  • tbt effects on the female genital system of Littorina littorea a possible indicator of tributyltin pollution
    Hydrobiologia, 1995
    Co-Authors: B. Bauer, P Fioroni, Jörg Oehlmann, Stefanie Liebe, E Stroben, Burkard Watermann
    Abstract:

    Specimens of the prosobranch Littorina littorea (L., 1758) collected along the East Frisian North Sea coast in summer 1993 exhibited alterations of the pallial oviduct termed as intersex in response to tributyltin (TBT) pollution. The range of TBT body burden was between 150.9 and 1289.5 µg as Sn kg−1 (dry wt.). Five stages of intersex development (0–4) could be distinguished and are documented with scanning electron micrographs. In stages 2–4, which can be found in the direct vicinity of harbours and marinas, the morphological malformations of the oviduct inhibit successful copulation and capsule formation, resulting in sterilization.

Stephen Widdicombe - One of the best experts on this subject based on the ideXlab platform.

  • exposure to elevated temperature and pco2 reduces respiration rate and energy status in the periwinkle Littorina littorea
    Physiological and Biochemical Zoology, 2011
    Co-Authors: Sedercor Melatunan, Simon D Rundle, Piero Calosi, John A Moody, Stephen Widdicombe
    Abstract:

    AbstractIn the future, marine organisms will face the challenge of coping with multiple environmental changes associated with increased levels of atmospheric Pco2, such as ocean warming and acidification. To predict how organisms may or may not meet these challenges, an in-depth understanding of the physiological and biochemical mechanisms underpinning organismal responses to climate change is needed. Here, we investigate the effects of elevated Pco2 and temperature on the whole-organism and cellular physiology of the periwinkle Littorina littorea. Metabolic rates (measured as respiration rates), adenylate energy nucleotide concentrations and indexes, and end-product metabolite concentrations were measured. Compared with values for control conditions, snails decreased their respiration rate by 31% in response to elevated Pco2 and by 15% in response to a combination of increased Pco2 and temperature. Decreased respiration rates were associated with metabolic reduction and an increase in end-product metabol...