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Sewage effluent has been identified as a potential source of metal(loid) contamination in the aquatic environment. The Sydney rock oyster, Saccostrea glomerata, can accumulate most metals and is well established as a biomonitor of metals in the marine environment. To determine if Burwood Beach wastewater treatment works (WWTW) is a source of metal(loid) contamination, S. glomerata was deployed for 6 weeks in effluent receiving waters (Burwood Beach near and Burwood Beach far) and at reference locations (Redhead, Fingal Island 1 and Fingal Island 2) at depths 4, 8 and 12 m. In dried oyster tissue, inductively coupled plasma mass spectrometry (ICPMS) was employed to measure concentrations of a suite of metal(loid)s including aluminium, arsenic, cadmium, copper, lead, iron, manganese, mercury, nickel, selenium, silver and zinc. It was found that for all metal(loid)s, S. glomerata tissue concentrations were not significantly higher at Burwood Beach locations in comparison to all reference locations. Concentrations of metal(loid)s were similar to those which have been detected in previous studies of background locations in New South Wales (NSW). Further, all metals fell below National Food Authority maximum residue levels (MRLs), except for arsenic and this does not appear uncommon for concentrations in biota within NSW. Comparisons to historical data suggested that concentrations of metal(loid)s in sewage effluent from Burwood Beach WWTW, assessed via concentrations in oyster tissue, are similar or lower, suggesting that changes in treatment processes initiated in the intervening time have lowered metallic inputs. [ABSTRACT FROM AUTHOR]

Background: The relationship between functional somatic syndromes and multiple somatic symptoms is unclear. Purpose: We assessed whether the number of somatic symptoms is a predictor of health status in three functional somatic syndromes (FSS). Methods: In a population-based study of 990 UK adults we assessed chronic widespread pain (CWP), chronic fatigue (CF) and irritable bowel syndrome (IBS) by questionnaire and medical record data. We assessed health status (Short Form 12 and EQ-5D), number of somatic symptoms (Somatic Symptom Inventory) and anxiety/depression (Hospital Anxiety and Depression Scale) both at baseline and at follow-up 1 year later. Results: The proportion of people with an FSS who also have multiple somatic symptoms (52-55 %) was similar in the three functional syndromes. The presence of multiple somatic symptoms was associated with more impaired health status both at baseline and at follow-up. This finding was not explained by severity of FSS. In the absence of multiple somatic symptoms, the health status of the FSS was fair or good. In multiple regression analysis, the number of somatic symptoms, the presence of a functional syndrome (CWP or CF) and anxiety/depression were predictors of EQ-5D thermometer at follow-up after adjustment for confounders. Conclusions: Multiple somatic symptoms in people with an FSS are associated with impaired health status and this cannot be explained by more severe functional syndrome or the presence of anxiety and depression. [ABSTRACT FROM AUTHOR]

lthough mounting evidence suggests exposure to estrogenic contaminants increases vitellogenin production in molluscs, demonstration of dose-response relationships and knowledge of the temporal nature of the vitellogenin response with continual exposure is currently lacking for biomarker utility. To address this knowledge gap, adult Sydney rock oysters, Saccostrea glomerata, were exposed to a range of environmentally relevant concentrations of 17α-ethynylestradiol (EE2) (0, 6.25, 12.5, 25 or 50 ng/l) in seawater under laboratory conditions. Vitellogenin induction and gonadal development was assessed following 4, 21 and 49 days exposure to EE2. Vitellogenin was found to increase in a dose dependent manner with EE2 exposure for females (4 and 49 days) and males (4 and 21 days). Histological examination of gonads revealed a number of individuals exhibited intersex (ovotestis) in 50 ng/l EE2 (after 21 days) and in 6.25 and 12.5 ng/l EE2 (after 49 days). Furthermore, a significant shift towards females was observed following 49 days exposure at 50 ng/l EE2 suggesting estrogenic exposure is capable of facilitating a progression for protandric males from male-intersex-female gametal status. Increases in female vitellogenin (4 days) were predictive of later increases in female developmental stages at 21 days and increases in oocyte area following 49 days. Male vitellogenin (4 days) was predictive of decreased male percentages and lower male developmental stages at 49 days. Vitellogenin in S. glomerata is a predictive biomarker of estrogenic exposure and effect if sampled soon after exposure and at the commencement of a gonadal development cycle. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore associations between social mobility and tumours of the upper aero-digestive tract (UADT), focussing on life-course transitions in social prestige (SP) based on occupational history. 1,796 cases diagnosed between 1993 and 2005 in ten European countries were compared with 1585 controls. SP was classified by the Standard International Occupational Prestige Scale (SIOPS) based on job histories. SIOPS was categorised in high ( H), medium ( M) and low ( L). Time weighted average achieved and transitions between SP with nine trajectories: H → H, H → M, H → L, M → H, M → M, M → L, L → H, L → M and L → L were analysed. Odds ratios (ORs) and 95%-confidence intervals [95%-CIs] were estimated with logistic regression models including age, consumption of fruits/vegetables, study centre, smoking and alcohol consumption. The adjusted OR for the lowest versus the highest of three categories (time weighted average of SP) was 1.28 [1.04–1.56]. The distance of SP widened between cases and controls during working life. The downward trajectory H → L gave an OR of 1.71 [0.75–3.87] as compared to H → H. Subjects with M → M and L → L trajectories ORs were also elevated relative to subjects with H → H trajectories. The association between SP and UADT is not fully explained by confounding factors. Downward social trajectory during the life course may be an independent risk factor for UADT cancers. [ABSTRACT FROM AUTHOR]

This study compared the accumulation of arsenic, copper and chromium by Pteris vittata and Pteris umbrosa grown in a glasshouse in soil from a timber treatment facility. Soil was collected from three locations. Accumulation (as percentage removed) varied between these soils but was not related to soil concentration. P. vittata was more efficient than P. umbrosa, both in accumulating As and metals in the below-ground plant parts and in translocating As to the fronds. Under the experimental conditions, only P. vittata could be effectively used in soil from one location for phytoremediation purposes. [ABSTRACT FROM AUTHOR]

Variation in glutathione antioxidant biochemistry in response to metal contamination and accumulation under field conditions was examined in the brachyurid grapsid, Parasesarma erythodactyla. Significant relationships suggesting accumulation were found between sediment metals and metals in crab tissue for Pb, Cu, Cr, Zn, and Se in males and Cd, Pb, Cr Zn, As, and Se in females. Higher pH and lower organic content were associated with greater uptake of selected metals in males and females. Higher salinity was related to increased metal uptake for Cu and Zn in males and lower salinities to increased Se uptake for males and females. When examining metals, which were elevated in crabs, patterns of site discrimination were similar to sediment metal site discrimination for both males and females. In terms of biochemical responses, glutathione levels remained constant while glutathione peroxidase activity was elevated in individuals where metals were elevated. Only females with the highest levels of accumulated metals exhibited increases in lipid peroxidation products. Glutathione peroxidase activity may be a sensitive biomarker of metal exposure and biological effect and lipid peroxides as a secondary marker when accumulated metals are high. [ABSTRACT FROM AUTHOR]

This article presents a study which discusses various issues related to sub-lethal behavioral effects of the water accommodated fractions of crude oil to gastropod mollusks. Sub-lethal impacts on individuals exposed to low levels of oil contaminants may be manifested as biochemical, carcinogenic, physiological and behavioral effects. These sub-lethal impacts may compromise an organism's survival and reproductive success in the long-term, and ultimately may result in effects at the population and community levels in situ. In the study, a range of crude oil water accommodated fraction exposures are employed in the laboratory to examine sub-lethal effects on spontaneous locomotor responses of a number of endemic Australian gastropod mollusks.

The article cites a study on effects of Zinc (Zn) exposure on chlorophyll a fluorescence in the grey mangrove, Avicennia marina (Forsk.) Vierh. Monitoring sub-lethal changes in photosynthesis, via a technique such as fluorescence, in response to metal stress not only indicates damage to the photosynthetic apparatus and accompanying changes in photosynthetic capacity, but also has consequences for reduced carbon assimilation, growth, survival and reproduction. Such effects may have implications for mangrove individuals and populations in the long term. Results of the study revealed that accumulated Zn levels in leaf tissues were on average 3 times lower than sediment metal concentrations, suggesting an exclusion mechanism to accumulation.

Clinical studies have shown that measurements of urine concentration of degradation products of C-terminal telopeptides of type I collagen provide a selective marker to assess bone resorption. Assays for C-telopeptide fragments have been described using antibodies generated against an eight amino acid synthetic peptide EKAHDGGR. In this study, we describe development of a rat monoclonal antibody against a synthetic linear peptide, DFSFLPQPPQEKAHDGGR, which we isolated and characterized from Paget's urine by chromatographic methods. An ELISA procedure was developed to evaluate the efficacy of this monoclonal to measure bone resorption and characterize urinary degradation products of C-terminal type I collagen. The measuring range of ELISA was 10-1,000 ng/ml with a detection limit of 10 ng/ml. Averaged intraassay and interassay CVs were <7% (n = 8) and <11% (n = 3), respectively. Mean spike and dilution recoveries range between 90 and 116%. In assessing the clinical performance, we observed approximately 48% higher values for postmenopausal patients (n = 20) compared with premenopausal women (n= 19), Z score = 2.7 (P = 0.0091). The discriminatory power to assess subtle changes in bone turnover between pre- and postmenopausal women compares well with the commercially available markers of bone resorption. Comparison of C-telopeptide concentration in a population including normal and osteoporotic patients (n = 74) shows a strong correlation with DPYR r = 0.95 (P < 0.001). In addition, in postmenopausal osteoporotic patients, a 44% (P < 0.05) decrease in C-telopeptide concentration was observed after 3 months of treatment with Alendronate, as compared with basal values. The antibody developed in this study displays a slightly different epitope than that reported previously using eight amino acid residues EKAHDGGR. In addition, isolation and characterization of circulating forms of C-telopeptide from healthy children by immunoaffinity purification revealed the presence of two novel urinary fragments corresponding to amino acid sequence EKAHDGGR and EKAHDG, in addition to the previously known two fragments composed of two alpha-1 chains linked together by a pyridinium crosslinks. The origin of the fragment EKAHDG could not be explained by the known mechanisms involved in collagen degradation, indicating that it could be a product of renal handling of C-telopeptide fragments generated from bone. The preliminary clinical data suggest that the new assay may be useful for further investigation of the clinical importance of measurement of these type I collagen degradation products. [ABSTRACT FROM AUTHOR]

Macrobenthic community assemblage diversity and abundance were monitored on both Cowan and Berowra Creeks in the estuarine reaches of the Hawkesbury River, Sydney Australia during 1997–1998. Natural sediment physicochemical differences were assessed, along with low-level anthropogenic contaminants including copper, lead, zinc, phosphorus and nitrogen. Contaminant levels at all sites were below sediment guideline values for biological effects. Natural physicochemical sediment differences were the main determinants in species assemblage patterns among sites. Three groupings of sites with similar assemblages were observed during February 1998. Berowra Creek sites, which were higher in organic content and silt/clay (and thus metals and nutrients), higher in pH and lower in salinity, were similar in terms of contributions by the polychaetes Ceratoneresis aequisetis, Scoloplos normalis, the isopod Cyathura hakea and the bivalve mollusc Soletellina alba. Sites on upper Cowan Creek, higher in organic content, silt/clay (nutrients and metals) and lower in salinity, were similar and separated from other sites in terms of the polychaete Carazziella victoriensis and the gastropod mollusc Nassarius jonasii. Sites lower in Cowan Creek, tended to be higher in sand content, more saline and lower in organic content and thus nutrient and metal concentrations. These sites were similar in terms of contributions of the polychaete Sigalion bandaensis and the bivalve molluscs, Mysella vitrea and Tellina deltoidalis. The biotic assemblage patterns were not maintained temporally, suggesting the importance of monitoring over time to assess possible future impacts. Aggregating species data to the family level resulted in similar site discrimination. Site differences were less distinct at higher taxonomic levels and suggests future monitoring at the family level is sufficient to detect assemblage differences among sites. The results obtained represent the difficulty in detecting responses to low-level contamination at the community level, and provide a sound anticipatory baseline for the assessment of future possible anthropogenic disturbance in the Hawkesbury River. [ABSTRACT FROM AUTHOR]

Nitrate dissimilation in chemostat grown cultures of Clostridium butyricum SS6 has been investigated. Sucrose limited cultures grown on nitrate produced nitrite as the principal end-product of nitrate reduction whilst under nitrate-limiting conditions ammonia accumulated in the spent media. Nitrate reduction was accompanied by the synthesis of a soluble nitrate reductase (123 nmol·NADH oxidised · min · mg protein) and in addition, under N-limiting conditions, a soluble nitrite reductase (56 nmol NADH oxidised min · mg protein). Corresponding ammonia grown cultures synthesised neither enzyme. Concurrent with the dissimilation of nitrate to nitrite and ammonia cell population densities increased by 18% (C-limitation) and 32% (N-limitation). Spent media analyses of the fermentation products from ammonia and nitrate grown cells showed the accumulation of acetate in nitrate dissimilating cultures. Molar ratios of acetate/butyrate increased by a factor of 5 (C-limitation) to 12 (N-limitation) upon adding nitrate to the growth medium. In C-limited cultures, grown on nitrate, hydrogenase activity was 340 nmol · min · mg protein and under N-limitation this increased to 906 nmol · min · mg protein. Since N-limited cultures are electron acceptor limited, the increase in hydrogenase activity enables excess electrons to be spilled by this route. [ABSTRACT FROM AUTHOR]

Rhodopseudomonas acidophila strain 7050 achieved balanced growth when provided with either asparagine or glutamine as nitrogen source. Under these growth conditions R. acidophila synthesized a mixed amidase which exhibited similar activity (223-422 nmol/min·mg protein) against either nitrogen source. Determination of the free intracellular amino acid pools show that deamidation of asparagine and glutamine resulted in elevated levels of both aspartate and glutamate. Cell-free extracts of R. acidophila showed significant aminotransferase activity, particulary glutamine-oxaloacetate aminotransferase (89.7-209.3 nmol/min·mg protein), glycine oxaloacetate aminotransferase (135-227 nmol/min ·mg protein), alanine glyoxylate aminotransferase (66.3-163.2 nmol/min·mg protein) and serineglyoxylate aminotransferase (57.1-68.4 nmol/min ·mg protein). Short term labelling experiments using C-glyoxylate show that glycine plays an important role in amino nitrogen transfer in R. acidophila and that the enzymes for the metabolism of glyoxylate via glycine, serine and hydroxypyruvate were present in cell-free extracts. These data confirm that R. acidophila can satisfy all its' nitrogen requirements by transamination. [ABSTRACT FROM AUTHOR]

The relationship between survival and 25 clinical and histologic variables was studied in 195 patients (171 women. 24 men) who satisfied stringent criteria for the diagnosis of primary biliary cirrhosis. The mean duration of follow-up was 6 yr (range 0-17). One hundred and sixteen patients died, 84% as the result of liver disease and 16% from nonhepatic causes. Using the Kaplan-Meier estimate, we calculated the mortality from liver disease to be 40% after 5 yr and 60% after 10 yr. Ascites, serum bilirubin level, variceal hemorrhage, and age were identified as independent clinical risk factors, and extent of hepatic fibrosis, bilirubino-stasis. and Mallory's hyalin were identified as independent histologic risk factors correlating with reduced survival. [ABSTRACT FROM AUTHOR]

Glucose was required for the transport of arabinose into Bifidobacterium breve. The non-metabolisable glucose analogue 2-deoxy- d-glucose (2-DG) did not facilitate assimilation of arabinose. Studies using d-[U-C]-labelled arabinose showed that it was fermented to pyruvate, formate, lactate and acetate, whereas the principal metabolic products of d-[U-C]-labelled glucose were acetate and formate. In contrast to glucose, arabinose was not incorporated into cellular macromolecules. A variety of metabolic inhibitors and inhibitors of sugar transport (proton ionophores, metal ionophores, compounds associated with electron transport) were used to investigate the mechanisms of sugar uptake. Only NaF, an inhibitor of substrate level phosphorylation, and 2-DG inhibited glucose assimilation. 2-DG had no effect on arabinose uptake, but NaF was stimulatory. High levels of phosphorylation of glucose and 2-DG by PEP and to a lesser degree, ATP were seen in phosphoenolpyruvate: phosphotransferase (PEP:PTS) assays. These data together with strong inhibition of glucose uptake by NaF suggest a role for phosphorylation in the transport process. Arabinose uptake in B. breve was not directly dependent on phosphorylation or any other energy-linked form of transport but may be assimilated by glucose-dependent facilitated diffusion. [ABSTRACT FROM AUTHOR]

This article reviews the epidemiology of cancer of the pancreas, both descriptive and analytical, at all times cognizant of the problems of misdiagnosis, particularly underdiagnosis, of this lethal disease that continue to hinder epidemiological studies. Pancreas cancer is consistently reported to occur more frequently in men than in women, in blacks than in whites, and in urban rather than rural population groups. In some countries, the mortality rates continue to rise, whereas in others, declining levels of disease can be seen among members of younger birth cohorts. Although some of these patterns can be explained by variation in pancreas cancer risk factors, many cannot. Analytical studies consistently demonstrate that cigaret smoking increases the risk of cancer of the pancreas, and this appears, at the present time, to be the only clearly demonstrated risk factor for pancreatic cancer. Although the association with disease risk and coffee consumption, alcohol consumption, occupational exposures, diabetes, pancreatitis, and other factors requires clarification, it appears likely that the most fruitful research area in the coming years may involve exploration of pancreatic cancer risk and nutritional practices. [ABSTRACT FROM AUTHOR]

Aim To identify distinct characteristics of unexplained orofacial pain that could be used by dental practitioners in making an early diagnosis.Methods Subjects reporting orofacial pain in a postal questionnaire-based cross-sectional survey were invited for clinical examination. The interviewer was blinded to the questionnaire responses of the subjects. A diagnosis was made following the examination and subjects were assigned into two groups: unexplained pain and dental pain. The questionnaire responses of subjects who had consulted a healthcare professional within these two groups were then compared with particular attention to demographics, orofacial pain characteristics, consultation behaviour and relationship with other unexplained syndromes.Results Subjects who had consulted for their pain and were assigned to the unexplained orofacial pain group were significantly (p <0.05) more likely to report the following characteristics: pain descriptors (nagging, aching, tingling), pain pattern (worse with stress), site (poorly localised), duration (persistent/chronic), high disability, multiple consultations and co-morbidities (teeth grinding, reporting of other unexplained syndromes).Conclusion This study has shown that unexplained orofacial pain has distinct characteristics that differentiate it from other common dental conditions. This provides a good evidence base which can reduce uncertainty among dental practitioners, allowing them to make an early diagnosis. [ABSTRACT FROM AUTHOR]

Aim To identify distinct characteristics of unexplained orofacial pain that could be used by dental practitioners in making an early diagnosis.Methods Subjects reporting orofacial pain in a postal questionnaire-based cross-sectional survey were invited for clinical examination. The interviewer was blinded to the questionnaire responses of the subjects. A diagnosis was made following the examination and subjects were assigned into two groups: unexplained pain and dental pain. The questionnaire responses of subjects who had consulted a healthcare professional within these two groups were then compared with particular attention to demographics, orofacial pain characteristics, consultation behaviour and relationship with other unexplained syndromes.Results Subjects who had consulted for their pain and were assigned to the unexplained orofacial pain group were significantly (p <0.05) more likely to report the following characteristics: pain descriptors (nagging, aching, tingling), pain pattern (worse with stress), site (poorly localised), duration (persistent/chronic), high disability, multiple consultations and co-morbidities (teeth grinding, reporting of other unexplained syndromes).Conclusion This study has shown that unexplained orofacial pain has distinct characteristics that differentiate it from other common dental conditions. This provides a good evidence base which can reduce uncertainty among dental practitioners, allowing them to make an early diagnosis. [ABSTRACT FROM AUTHOR]