1,975 research outputs found

    Detection and metabolic investigations of a novel designer steroid: 3-chloro-17α-methyl-5α-androstan-17β-ol

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    In 2012, seized capsules containing white powder were analyzed to show the presence of unknown steroid-related compounds. Subsequent gas chromatography–mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) investigations identified a mixture of 3α- and 3β- isomers of the novel compound; 3-chloro-17α-methyl-α-androstan-17β-ol. Synthesis of authentic reference materials followed by comparison of NMR, GC-MS and gas chromatography-tandem mass spectrometry (GC-MS/MS) data confirmed the finding of a new ‘designer’ steroid. Furthermore, in vitro androgen bioassays showed potent activity highlighting the potential for doping using this steroid. Due to the potential toxicity of the halogenated steroid, in vitro metabolic investigations of 3α-chloro-17α-methyl-α-androstan-17β-ol using equine and human S9 liver fractions were performed. For equine, GC-MS/MS analysis identified the diagnostic 3α-chloro-17α-methyl-5α-androstane-16α,17β-diol metabolite. For human, the 17α-methyl-α-androstane-3α,17β-diol metabolite was found. Results from these studies were used to verify the ability of GC-MS/MS precursor-ion scanning techniques to support untargeted detection strategies for designer steroids in anti-doping analyses.Synthesis and in vitro metabolic investigations of 3α/β-chloro-17α-methyl-5α-androstan -17β-ol was suppo rted by the Austr a-lian Research Council Linkage Grant (LP120200444) Strat egies for the detection of designer ster oids in ra cehorses

    Trainee teachers' use of blogs as private reflections for professional development

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    A collaborative research project between Sheffield Hallam University and Nottingham Trent University in the UK investigated the use of blogs with trainee teachers as an alternative to reflective paper-based diaries. An action research case study, involving focus groups of post-graduate (secondary) trainee teachers (one group from each University) was undertaken to determine attitudes and perceptions of blogging as an appropriate tool to support reflective professional development. The findings indicate that the use of blogs by the trainee teachers had a positive impact overall, and provide concrete evidence of their development as emerging professional teachers. Unlike traditional paper-based systems, blogs provided ongoing opportunities for the tutor to assist the trainees in their development as reflective practitioners. This paper seeks to share the findings of this research which the authors believe could be applicable to other areas of Higher Education.</p

    Rapid cultural adaptation can facilitate the evolution of large-scale cooperation

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    Over the past several decades, we have argued that cultural evolution can facilitate the evolution of large-scale cooperation because it often leads to more rapid adaptation than genetic evolution, and, when multiple stable equilibria exist, rapid adaptation leads to variation among groups. Recently, Lehmann, Feldman, and colleagues have published several papers questioning this argument. They analyze models showing that cultural evolution can actually reduce the range of conditions under which cooperation can evolve and interpret these models as indicating that we were wrong to conclude that culture facilitated the evolution of human cooperation. In the main, their models assume that rates of cultural adaption are not strong enough compared to migration to maintain persistent variation among groups when payoffs create multiple stable equilibria. We show that Lehmann et al. reach different conclusions because they have made different assumptions. We argue that the assumptions that underlie our models are more consistent with the empirical data on large-scale cultural variation in humans than those of Lehmann et al., and thus, our models provide a more plausible account of the cultural evolution of human cooperation in large groups

    Validating a prediction tool to determine the risk of nosocomial multidrug-resistant Gram-negative bacilli infection in critically ill patients: A retrospective case–control study

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    BACKGROUND:The Singapore GSDCS score was developed to enable clinicians predict the risk of nosocomial multidrug-resistant Gram-negative bacilli (RGNB) infection in critically ill patients. We aimed to validate this score in a UK setting. METHOD:A retrospective case-control study was conducted including patients who stayed for more than 24h in intensive care units (ICUs) across two tertiary National Health Service hospitals in London, UK (April 2011-April 2016). Cases with RGNB and controls with sensitive Gram-negative bacilli (SGNB) infection were identified. RESULTS:The derived GSDCS score was calculated from when there was a step change in antimicrobial therapy in response to clinical suspicion of infection as follows: prior Gram-negative organism, Surgery, Dialysis with end-stage renal disease, prior Carbapenem use and intensive care Stay of more than 5 days. A total of 110 patients with RGNB infection (cases) were matched 1:1 to 110 geotemporally chosen patients with SGNB infection (controls). The discriminatory ability of the prediction tool by receiver operating characteristic curve analysis in our validation cohort was 0.75 (95% confidence interval 0.65-0.81), which is comparable with the area under the curve of the derivation cohort (0.77). The GSDCS score differentiated between low- (0-1.3), medium- (1.4-2.3) and high-risk (2.4-4.3) patients for RGNB infection (P<0.001) in a UK setting. CONCLUSION:A simple bedside clinical prediction tool may be used to identify and differentiate patients at low, medium and high risk of RGNB infection prior to initiation of prompt empirical antimicrobial therapy in the intensive care setting

    Effectiveness of interventions to promote healthy diet in primary care: systematic review and meta-analysis of randomised controlled trials

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    Background A diet rich in fruit, vegetables and dietary fibre and low in fat is associated with reduced risk of chronic disease. This review aimed to estimate the effectiveness of interventions to promote healthy diet for primary prevention among participants attending primary care.&lt;p&gt;&lt;/p&gt; Methods A systematic review of trials using individual or cluster randomisation of interventions delivered in primary care to promote dietary change over 12 months in healthy participants free from chronic disease or defined high risk states. Outcomes were change in fruit and vegetable intake, consumption of total fat and fibre and changes in serum cholesterol concentration.&lt;p&gt;&lt;/p&gt; Results Ten studies were included with 12,414 participants. The design and delivery of interventions were diverse with respect to grounding in behavioural theory and intervention intensity. A meta-analysis of three studies showed an increase in fruit consumption of 0.25 (0.01 to 0.49) servings per day, with an increase in vegetable consumption of 0.25 (0.06 to 0.44) serving per day. A further three studies that reported on fruit and vegetable consumption together showed a pooled increment of 0.50 (0.13 to 0.87) servings per day. The pooled effect on consumption of dietary fibre, from four studies, was estimated to be 1.97 (0.43 to 3.52) gm fibre per day. Data from five studies showed a mean decrease in total fat intake of 5.2% of total energy (1.5 to 8.8%). Data from three studies showed a mean decrease in serum cholesterol of 0.10 (-0.19 to 0.00) mmol/L.&lt;p&gt;&lt;/p&gt; Conclusion Presently-reported interventions to promote healthy diet for primary prevention in primary care, which illustrate a diverse range of intervention methods, may yield small beneficial changes in consumption of fruit, vegetables, fibre and fat over 12 months. The present results do not exclude the possibility that more effective intervention strategies might be developed.&lt;p&gt;&lt;/p&gt

    Evaluating 'Prefer not to say' Around Sensitive Disclosures

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    As people's offline and online lives become increasingly entwined, the sensitivity of personal information disclosed online is increasing. Disclosures often occur through structured disclosure fields (e.g., drop-down lists). Prior research suggests these fields may limit privacy, with non-disclosing users being presumed to be hiding undesirable information. We investigated this around HIV status disclosure in online dating apps used by men who have sex with men. Our online study asked participants (N=183) to rate profiles where HIV status was either disclosed or undisclosed. We tested three designs for displaying undisclosed fields. Visibility of undisclosed fields had a significant effect on the way profiles were rated, and other profile information (e.g., ethnicity) could affect inferences that develop around undisclosed information. Our research highlights complexities around designing for non-disclosure and questions the voluntary nature of these fields. Further work is outlined to ensure disclosure control is appropriately implemented around online sensitive information disclosures

    Effect of tuberculosis screening and retention interventions on early antiretroviral therapy mortality in Botswana: a stepped-wedge cluster randomized trial.

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    BACKGROUND: Undiagnosed tuberculosis (TB) remains the most common cause of HIV-related mortality. Xpert MTB/RIF (Xpert) is being rolled out globally to improve TB diagnostic capacity. However, previous Xpert impact trials have reported that health system weaknesses blunted impact of this improved diagnostic tool. During phased Xpert rollout in Botswana, we evaluated the impact of a package of interventions comprising (1) additional support for intensified TB case finding (ICF), (2) active tracing for patients missing clinic appointments to support retention, and (3) Xpert replacing sputum-smear microscopy, on early (6-month) antiretroviral therapy (ART) mortality. METHODS: At 22 clinics, ART enrollees >?12?years old were eligible for inclusion in three phases: a retrospective standard of care (SOC), prospective enhanced care (EC), and prospective EC plus Xpert (EC+X) phase. EC and EC+X phases were implemented as a stepped-wedge trial. Participants in the EC phase received SOC plus components 1 (strengthened ICF) and 2 (active tracing) of the intervention package, and participants in the EC+X phase received SOC plus all three intervention package components. Primary and secondary objectives were to compare all-cause 6-month ART mortality between SOC and EC+X and between EC and EC+X phases, respectively. We used adjusted analyses, appropriate for study design, to control for baseline differences in individual-level factors and intra-facility correlation. RESULTS: We enrolled 14,963 eligible patients: 8980 in SOC, 1768 in EC, and 4215 in EC+X phases. Median age of ART enrollees was 35 and 64% were female. Median CD4 cell count was lower in SOC than subsequent phases (184/?L in SOC, 246/?L in EC, and 241/?L in EC+X). By 6?months of ART, 461 (5.3%) of SOC, 54 (3.2%) of EC, and 121 (3.0%) of EC+X enrollees had died. Compared with SOC, 6-month mortality was lower in the EC+X phase (adjusted hazard ratio, 0.77; 95% confidence interval, 0.61-0.97, p?=?0.029). Compared with EC enrollees, 6-month mortality was similar among EC+X enrollees. CONCLUSIONS: Interventions to strengthen ICF and retention were associated with lower early ART mortality. This new evidence highlights the need to strengthen ICF and retention in many similar settings. Similar to other trials, no additional mortality benefit of replacing sputum-smear microscopy with Xpert was observed. TRIAL REGISTRATION: Retrospectively registered: ClinicalTrials.gov (NCT02538952)

    Serological evidence of a pararubulavirus and a betacoronavirus in the geographically isolated Christmas Island flying-fox (Pteropus natalis)

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    Due to their geographical isolation and small populations, insular bats may not be able to maintain acute immunizing viruses that rely on a large population for viral maintenance. Instead, endemic transmission may rely on viruses establishing persistent infections within hosts or inducing only short-lived neutralizing immunity. Therefore, studies on insular populations are valuable for developing broader understanding of viral maintenance in bats. The Christmas Island flying-fox (CIFF; Pteropus natalis) is endemic on Christmas Island, a remote Australian territory, and is an ideal model species to understand viral maintenance in small, geographically isolated bat populations. Serum or plasma (n = 190), oral swabs (n = 199), faeces (n = 31), urine (n = 32) and urine swabs (n = 25) were collected from 228 CIFFs. Samples were tested using multiplex serological and molecular assays, and attempts at virus isolation to determine the presence of paramyxoviruses, betacoronaviruses and Australian bat lyssavirus. Analysis of serological data provides evidence that the species is maintaining a pararubulavirus and a betacoronavirus. There was little serological evidence supporting the presence of active circulation of the other viruses assessed in the present study. No viral nucleic acid was detected and no viruses were isolated. Age-seropositivity results support the hypothesis that geographically isolated bat populations can maintain some paramyxoviruses and coronaviruses. Further studies are required to elucidate infection dynamics and characterize viruses in the CIFF. Lastly, apparent absence of some pathogens could have implications for the conservation of the CIFF if a novel disease were introduced into the population through human carriage or an invasive species. Adopting increased biosecurity protocols for ships porting on Christmas Island and for researchers and bat carers working with flying-foxes are recommended to decrease the risk of pathogen introduction and contribute to the health and conservation of the species

    A systematic review of reviews: Recruitment and retention of rural family physicians

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    The recruitment and retention of family physicians in rural and remote communities has been the topic of many reviews; however, a lack of consensus among them with regard to which factors are most influential makes it difficult for setting priorities. We performed a systematic review of reviews which helped to establish an overall conclusion and provided a set of fundamental influential factors, regardless of the consistency or generalisability of the findings across reviews. This review also identified the knowledge gaps and areas of priority for future research. Methods: A literature search was conducted to find the review articles discussing the factors of recruitment or retention of rural family physicians. Results were screened by two independent reviewers. The number of times that each factor was mentioned in the literature was counted and ordered in terms of frequency. Results: The literature search identified 84 systematic reviews. Fourteen met the inclusion criteria, from which 158 specific factors were identified and summarised into 11 categories: personal, health, family, training, practice, work, professional, pay, community, regional and system/legislation. The three categories referenced most often were training, personal and practice. The specific individual factors mentioned most often in the literature were 'medical school characteristics', 'longitudinal rural training' and 'raised in a small town'. Conclusion: The three most often cited categories resemble three distinct phases of a family physician's life: pre-medical school, medical school and post-medical school. To increase the number of physicians who choose to work in rural practice, strategies must encompass and promote continuity across all three of these phases. The results of this systematic review will allow for the identification of areas of priority that require further attention to develop appropriate strategies to improve the number of family physicians working in rural and remote locations

    Ruthenium polypyridyl complexes and their modes of interaction with DNA : is there a correlation between these interactions and the antitumor activity of the compounds?

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    Various interaction modes between a group of six ruthenium polypyridyl complexes and DNA have been studied using a number of spectroscopic techniques. Five mononuclear species were selected with formula [Ru(tpy) L1L2](2-n)?, and one closely related dinuclear cation of formula [{Ru(apy)(tpy)}2{l-H2N(CH2)6NH2}]4?. The ligand tpy is 2,20:60,200-terpyridine and the ligand L1 is a bidentate ligand, namely, apy (2,20-azobispyridine), 2-phenylazopyridine, or 2-phenylpyridinylmethylene amine. The ligand L2 is a labile monodentate ligand, being Cl-, H2O, or CH3CN. All six species containing a labile L2 were found to be able to coordinate to the DNA model base 9-ethylguanine by 1H NMR and mass spectrometry. The dinuclear cationic species, which has no positions available for coordination to a DNA base, was studied for comparison purposes. The interactions between a selection of four representative complexes and calf-thymus DNA were studied by circular and linear dichroism. To explore a possible relation between DNA-binding ability and toxicity, all compounds were screened for anticancer activity in a variety of cancer cell lines, showing in some cases an activity which is comparable to that of cisplatin. Comparison of the details of the compound structures, their DNA binding, and their toxicity allows the exploration of structure–activity relationships that might be used to guide optimization of the activity of agents of this class of compounds
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