Inter-population variability in the reproductive morphology of the shore crab (Carcinus maenas): Evidence of endocrine disruption in a marine crustacean?

Environmental contaminants that are capable of causing endocrine disrupting effects are currently a major cause for concern. These chemicals are known to influence the reproductive development of vertebrates by mimicking or antagonising the actions of endogenous hormones. However, little is known regarding their potential effects on invertebrates. Here we examine variations in the reproductive morphology of the shore crab (Carcinus maenas) for evidence of endocrine disruption. Crabs were collected from a number of sites comprising a putative gradient of exposure to endocrine disrupting chemicals. Patterns of inter-population variability in the expression of sexually dimorphic traits were then examined for evidence of hormone disruption. Extensive variability was detected and patterns of chelal morphology were consistent with the gradient of endocrine disruption. However, overall, the patterns of morphological variability were not consistent with hormonally-mediated effects. This suggests that shore crabs are not susceptible to the same type of endocrine disrupting effects that have been detected in vertebrates, which are most commonly mediated via the oestrogen receptor. However, the potential for androgenic effects on crustacean morphology are discussed

Mixtures of Chemicals in Water: Implications of chemical legislation and environmental policy

Scientists have shown that mixtures of chemicals can act together to reduce the reproductive capacity of fish even if each individual chemical in the mixture is present at a concentration that does not cause an adverse effect. This evidence demonstrates that legislation based on the assessment of single chemicals may not be sufficiently protective and suggest that there is a need for a review of existing environmental policy

Interactive visualisation and exploration of biological data

International audienceno abstrac

Micropenis: an important early sign of congenital hypopituitarism

Micropenis is an important sign in neonates, since it may be the only clue to the diagnosis of panhypopituitarism, a potentially lethal but eminently treatable condition

A tale of three cities: persisting high HIV prevalence, risk behaviour and undiagnosed infection in community samples of men who have sex with men

Objectives: To examine the geographical variations in HIV prevalence (diagnosed and undiagnosed), use of sexual health services, sexually transmitted infections and sexual behaviour in a community sample of men who have sex with men in three cities in England, specifically London, Brighton and Manchester.Methods: Cross-sectional surveys of men visiting gay community venues in three large cities in England. Men self-completed a questionnaire and provided an anonymous oral fluid sample for HIV antibody testing.Results: HIV prevalence ranged from 8.6% to 13.7% in the three cities. Over one-third of HIV infection remained undiagnosed in all sites despite 69% of HIV-positive men reporting attending a genitourinary medicine clinic in the last year. Similar and high levels of risk behaviour were reported in all three cities. 18% of HIV-negative men and 37% of HIV-positive men reported unprotected anal intercourse with more than one partner in the last year. 20% of negative men and 41% of positive men reported an STI in the last year.Conclusions: Across all cities, despite widespread availability of anti-retroviral treatment and national policy to promote HIV testing, many HIV infections remain undiagnosed. Data from this community sample demonstrate high levels of risk behaviour and STI incidence, especially among those who are HIV positive. Renewed efforts are needed to increase diagnosis and to reduce risk behaviour to stem the continuing transmission of HIV

The problem of interpretation in vignette methodology in research with young people

In this paper we explore how interpretation is dealt with by researchers using a vignette methodology. Researchers using vignette methodology often struggle with interpretation: how to interpret the responses when participants shift between discussing the vignettes as themselves, taking the perspective of the character in the vignette and commenting on what ‘ought’ to happen. We argue that by foregrounding a consideration of the method with an explicitly articulated theoretical position of dialogicality, issues inherent in interpretation become a valuable addition to the research rather than an obstacle to be overcome. In the paper we discuss ‘Louise’ a young carer, detailing the various positions she takes in her talk about the vignette of Mary, a fictitious young carer, to illustrate how a perspective based in dialogical theory contributed to the analysis of her various moves through different identity positions

Preliminary data on the influence of rearing temperature on the growth and reproductive status of fathead minnows Pimephales promelas

This article has been made available through the Brunel Open Access Publishing Fund and is available from the specified link - Copyright @ 2011 Brian JV et al.An investigation into the influence of temperature on the growth and reproductive status of the fathead minnow Pimephales promelas revealed that, while there was no clear effect of treatment on sex differentiation, ovarian tissue from female fish reared under the highest temperature regime contained large amounts of undefined tissue containing no germ cells. Furthermore, both male and female fish exhibited differences in length mass, condition and somatic indices, and in the expression of secondary sexual characteristics. The patterns observed are discussed in the context of climate change