Oestrogens and anti-androgens in the aquatic environment and their effects on fish

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonEndocrine disrupting chemicals (EDCs) can enter the aquatic environment via wastewater treatment work (WwTW) effluents. Oestrogenic and (anti-)androgenic chemicals present in effluents affect the reproductive health of fish living downstream of these effluents. The effects of WwTW effluent before and after the addition of an advanced granular activated carbon (GAC) treatment; installed to reduce EDCs, are compared. In laboratory studies, no oestrogenic effects of standard or GAC effluent were observed in fathead minnows (FHM; Pimephales promelas). However, the standard effluent elicited possible anti-androgenic effects not observed in the GAC-treated effluent. In the river receiving this effluent, wild roach (Rutilus rutilus) were sampled before and after the GAC addition. Here oestrogenic effects were observed in the roach, and these effects were reduced following the GAC addition to the WwTW, but not completely removed. Over 100 chemicals previously detected in WwTW effluents were examined for (anti-)androgenic activity using an in vitro yeast-based assay. Toxicity can cause false positive results in this assay. Investigations, including employing a modified version of the in vitro assay, were conducted to improve the assay’s reliability. Then, assessments of the most potent anti-androgenic chemicals were made to determine if they were likely to cause a risk to the environment. Currently, the best in vivo fish screen for (anti-)androgenic activity utilises the induction of spiggin, an androgen dependent glue-like protein, normally produced by male 3-spined stickleback (Gasterosteus aculeatus) during nest building. Male FHMs also glue their mates’ eggs to substrate. Therefore, FHM may have homologous androgen dependant genes/proteins which could serve as biomarkers of (anti-)androgenic activity. Spiggin-like primers were designed and used to look for spiggin-like genes in tissues collected from FHM. However, none of the spiggin-like primers were male specific and further work is needed to determine if similar androgen dependant spiggin-like proteins are present in FHM

Taking on and taking over : choice and control for physically disabled young adults

This study looked at ways of supporting physically disabled young adults to achieve their preferred levels of control over care and support arrangements: * What are physically disabled young adults experiences of managing their care and support arrangements? * How can they be better supported? Key findings and practice implications are included. A video about the research findings is also available and a poster showing the challenges and solutions for supporting young physically disabled people

Taking on choice and control in personal care and support : the experiences of physically disabled young adults

Summary: Research on self-directed care has focused on older people and adults with learning disabilities or mental health difficulties. This paper reports physically disabled young adults’ experiences of self-directed care. Such work is important because young adults are a ‘minority’ group within adult social care. This, and their still developing life skills and lack of life experience, may have a bearing on their experiences of self-directed care and associated support needs. An exploratory qualitative study using semi-structured interviews investigated this issue. Participants were aged 19-29 years with a range of congenital and acquired impairments. Findings: Many aspects of interviewees’ experiences of self-directed care appeared to be influenced by their limited life experience, the fact they are still developing life skills and are a minority group within adult social care. Interviewees identified their lack of life experience and self-confidence as making them cautious in assuming responsibility for their care arrangements and, typically, their desire for on-going parental support. They also believed their age and life stage contributed to difficulties managing carers and PAs. Preferences around the characteristics of carers/PAs were influenced by their age and desire to integrate into mainstream activities. Information provided by statutory services did not (fully) acknowledge that some users were young adults. Applications: Compared to other physically disabled users of adult social care, young adults’ under-developed life skills and lack of life experience influences their experiences as users, and the support they needed to assume control of their care arrangements. Tailored information and support for this ‘minority group’ is required. Keywords: self- or consumer-directed support; personalization; adult social care; physical disability; young adults; transitio

A new family of phosphoinositide phosphatases in microorganisms: identification and biochemical analysis

<p>Abstract</p> <p>Background</p> <p>Phosphoinositide metabolism is essential to membrane dynamics and impinges on many cellular processes, including phagocytosis. Modulation of phosphoinositide metabolism is important for pathogenicity and virulence of many human pathogens, allowing them to survive and replicate in the host cells. Phosphoinositide phosphatases from bacterial pathogens are therefore key players in this modulation and constitute attractive targets for chemotherapy. MptpB, a virulence factor from <it>Mycobacterium tuberculosis</it>, has phosphoinositide phosphatase activity and a distinct active site P-loop signature HCXXGKDR that shares characteristics with eukaryotic lipid phosphatases and protein tyrosine phosphatases. We used this P-loop signature as a "diagnostic motif" to identify related putative phosphatases with phosphoinositide activity in other organisms.</p> <p>Results</p> <p>We found more than 200 uncharacterised putative phosphatase sequences with the conserved signature in bacteria, with some related examples in fungi and protozoa. Many of the sequences identified belong to recognised human pathogens. Interestingly, no homologues were found in any other organisms including Archaea, plants, or animals. Phylogenetic analysis revealed that these proteins are unrelated to classic eukaryotic lipid phosphatases. However, biochemical characterisation of those from <it>Listeria monocytogenes </it>and <it>Leishmania major</it>, demonstrated that, like MptpB, they have phosphatase activity towards phosphoinositides. Mutagenesis studies established that the conserved Asp and Lys in the P-loop signature (HCXXG<b>KD</b>R) are important in catalysis and substrate binding respectively. Furthermore, we provide experimental evidence that the number of basic residues in the P-loop is critical in determining activity towards poly-phosphoinositides.</p> <p>Conclusion</p> <p>This new family of enzymes in microorganisms shows distinct sequence and biochemical characteristics to classic eukaryotic lipid phosphatases and they have no homologues in humans. This study provides a foundation for examining the biological role of this new family of phosphatases and their potential as pharmaceutical targets against infectious diseases.</p

No substantial changes in estrogen receptor and estrogen-related receptor orthologue gene transcription in Marisa cornuarietis exposed to estrogenic chemicals

This article is made available through the Brunel Open Access Publishing Fund. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-No Derivative Works License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.Estrogen receptor orthologues in molluscs may be targets for endocrine disruptors, although mechanistic evidence is lacking. Molluscs are reported to be highly susceptible to effects caused by very low concentrations of environmental estrogens which, if substantiated, would have a major impact on the risk assessment of many chemicals. The present paper describes the most thorough evaluation to-date of the susceptibility of Marisa cornuarietis ER and ERR gene transcription to modulation by vertebrate estrogens in vivo and in vitro. We investigated the effects of estradiol-17β and 4-tert-Octylphenol exposure on in vivo estrogen receptor (ER) and estrogen-related receptor (ERR) gene transcription in the reproductive and neural tissues of the gastropod snail M. cornuarietis over a 12-week period. There was no significant effect (p > 0.05) of treatment on gene transcription levels between exposed and non-exposed snails. Absence of a direct interaction of estradiol-17β and 4-tert-Octylphenol with mollusc ER and ERR protein was also supported by in vitro studies in transfected HEK-293 cells. Additional in vitro studies with a selection of other potential ligands (including methyl-testosterone, 17α-ethinylestradiol, 4-hydroxytamoxifen, diethylstilbestrol, cyproterone acetate and ICI182780) showed no interaction when tested using this assay. In repeated in vitro tests, however, genistein (with mcER-like) and bisphenol-A (with mcERR) increased reporter gene expression at high concentrations only (>10−6 M for Gen and >10−5 M for BPA, respectively). Like vertebrate estrogen receptors, the mollusc ER protein bound to the consensus vertebrate estrogen-response element (ERE). Together, these data provide no substantial evidence that mcER-like and mcERR activation and transcript levels in tissues are modulated by the vertebrate estrogen estradiol-17β or 4-tert-Octylphenol in vivo, or that other ligands of vertebrate ERs and ERRs (with the possible exception of genistein and bisphenol A, respectively) would do otherwise.BBSR

Children in Scotland Requiring Palliative Care : identifying numbers and needs (The ChiSP Study)

This report sets out the findings from an investigation into the numbers of children and young people with life-limiting conditions in Scotland, and what current evidence tells us about their, and their families’, psychosocial support needs. The overall purpose of the study was to develop an evidence base to support and inform planning for children’s palliative care in Scotland. It is hoped that the evidence generated will be a resource to organisations with responsibility for, or delivering services to, children and young people with life-limiting conditions

COMPRENDO: Focus and approach

Tens of thousands of man-made chemicals are in regular use and discharged into the environment. Many of them are known to interfere with the hormonal systems in humans and wildlife. Given the complexity of endocrine systems, there are many ways in which endocrine-disrupting chemicals (EDCs) can affect the body’s signaling system, and this makes unraveling the mechanisms of action of these chemicals difficult. A major concern is that some of these EDCs appear to be biologically active at extremely low concentrations. There is growing evidence to indicate that the guiding principle of traditional toxicology that “the dose makes the poison” may not always be the case because some EDCs do not induce the classical dose–response relationships. The European Union project COMPRENDO (Comparative Research on Endocrine Disrupters—Phylogenetic Approach and Common Principles focussing on Androgenic/Antiandrogenic Compounds) therefore aims to develop an understanding of potential health problems posed by androgenic and antiandrogenic compounds (AACs) to wildlife and humans by focusing on the commonalities and differences in responses to AACs across the animal kingdom (from invertebrates to vertebrates)

Comparison of Short-Term Estrogenicity Tests for Identification of Hormone-Disrupting Chemicals

The aim of this study was to compare results obtained by eight different short-term assays of estrogenlike actions of chemicals conducted in 10 different laboratories in five countries. Twenty chemicals were selected to represent direct-acting estrogens, compounds with estrogenic metabolites, estrogenic antagonists, and a known cytotoxic agent. Also included in the test panel were 17β-estradiol as a positive control and ethanol as solvent control. The test compounds were coded before distribution. Test methods included direct binding to the estrogen receptor (ER), proliferation of MCF-7 cells, transient reporter gene expression in MCF-7 cells, reporter gene expression in yeast strains stably transfected with the human ER and an estrogen-responsive reporter gene, and vitellogenin production in juvenile rainbow trout. 17β-Estradiol, 17α-ethynyl estradiol, and diethylstilbestrol induced a strong estrogenic response in all test systems. Colchicine caused cytotoxicity only. Bisphenol A induced an estrogenic response in all assays. The results obtained for the remaining test compounds—tamoxifen, ICI 182.780, testosterone, bisphenol A dimethacrylate, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol dodecylethoxylate, butylbenzylphthalate, dibutylphthalate, methoxychlor, o,p′-DDT, p,p′-DDE, endosulfan, chlomequat chloride, and ethanol—varied among the assays. The results demonstrate that careful standardization is necessary to obtain a reasonable degree of reproducibility. Also, similar methods vary in their sensitivity to estrogenic compounds. Thus, short-term tests are useful for screening purposes, but the methods must be further validated by additional interlaboratory and interassay comparisons to document the reliability of the methods