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Augustine T. Choko Peter MacPherson Emily L. Webb Barbara A. Willey Helena Feasy Rodrick Sambakunsi Aaron Mdolo Simon D. Makombe Nicola Desmond Richard Hayes Hendramoorthy Maheswaran Elizabeth L. Corbett 《PLoS medicine》2015,12(9)
BackgroundHome-based HIV testing and counselling (HTC) achieves high uptake, but is difficult and expensive to implement and sustain. We investigated a novel alternative based on HIV self-testing (HIVST). The aim was to evaluate the uptake of testing, accuracy, linkage into care, and health outcomes when highly convenient and flexible but supported access to HIVST kits was provided to a well-defined and closely monitored population.ConclusionsCommunity-based HIVST achieved high coverage in two successive years and was safe, accurate, and acceptable. Proactive HIVST strategies, supported and monitored by communities, could substantially complement existing approaches to providing early HIV diagnosis and periodic repeat testing to adolescents and adults in high-HIV settings. 相似文献
123.
ManTek Yeung Rose Hurren Carine Nemr Xiaoming Wang Samantha Hershenfeld Marcela Gronda Sanduni Liyanage Yan Wu Jeevan Augustine Eric A. Lee Paul A. Spagnuolo Noel Southall Catherine Chen Wei Zheng Danny V. Jeyaraju Mark D. Minden Rebecca Laposa Aaron D. Schimmer 《Apoptosis : an international journal on programmed cell death》2015,20(6):811-820
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Heli Routti Bjørn Munro Jenssen Christian Lydersen Christina Bäckman Augustine Arukwe Madeleine Nyman Kit M. Kovacs Geir Wing Gabrielsen 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2010,155(1):70-76
This study investigates the potential effects of moulting, and the concomitant period of fasting undertaken by ringed seals, on hormone, vitamin and contaminant status in adult animals in a population from Svalbard, Norway, which has relatively low contaminant levels. Concentrations of circulating total and free thyroxine and triiodothyronine, circulating and hepatic vitamin A, hepatic persistent organic pollutants and their circulating hydroxyl metabolites were higher in moulting seals compared to pre-moulting seals. The opposite trend was observed for body condition, circulating calcitriol levels and hepatic mRNA expression of thyroid hormone receptor β. No differences were observed for circulating or hepatic vitamin E levels or hepatic mRNA expressions for deioidinase 1 or 2, or retinoic acid receptor α between the two seal groups. The observed differences are likely the result of increased metabolic rates required during moulting to maintain thermal balance and replace the pelage, in combination with mobilization of lipid soluble compounds from blubber stores during the fasting period that is associated with moulting. The present study shows that contaminant levels and their relationships with physiological or endogenous variables can be highly confounded by moulting/fasting status. Thus, moulting status and body condition should be taken into consideration when using variables related to thyroid, calcium or vitamin A homeostasis as biomarkers for contaminant effects. 相似文献
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A spatial genetics approach to inform vector control of tsetse flies (Glossina fuscipes fuscipes) in Northern Uganda 下载免费PDF全文
Norah Saarman Robert Opiro Chaz Hyseni Richard Echodu Kirstin Dion Elizabeth A. Opiyo Augustine W. Dunn Giuseppe Amatulli Serap Aksoy Adalgisa Caccone 《Ecology and evolution》2018,8(11):5336-5354
Tsetse flies (genus Glossina) are the only vector for the parasitic trypanosomes responsible for sleeping sickness and nagana across sub‐Saharan Africa. In Uganda, the tsetse fly Glossina fuscipes fuscipes is responsible for transmission of the parasite in 90% of sleeping sickness cases, and co‐occurrence of both forms of human‐infective trypanosomes makes vector control a priority. We use population genetic data from 38 samples from northern Uganda in a novel methodological pipeline that integrates genetic data, remotely sensed environmental data, and hundreds of field‐survey observations. This methodological pipeline identifies isolated habitat by first identifying environmental parameters correlated with genetic differentiation, second, predicting spatial connectivity using field‐survey observations and the most predictive environmental parameter(s), and third, overlaying the connectivity surface onto a habitat suitability map. Results from this pipeline indicated that net photosynthesis was the strongest predictor of genetic differentiation in G. f. fuscipes in northern Uganda. The resulting connectivity surface identified a large area of well‐connected habitat in northwestern Uganda, and twenty‐four isolated patches on the northeastern margin of the G. f. fuscipes distribution. We tested this novel methodological pipeline by completing an ad hoc sample and genetic screen of G. f. fuscipes samples from a model‐predicted isolated patch, and evaluated whether the ad hoc sample was in fact as genetically isolated as predicted. Results indicated that genetic isolation of the ad hoc sample was as genetically isolated as predicted, with differentiation well above estimates made in samples from within well‐connected habitat separated by similar geographic distances. This work has important practical implications for the control of tsetse and other disease vectors, because it provides a way to identify isolated populations where it will be safer and easier to implement vector control and that should be prioritized as study sites during the development and improvement of vector control methods. 相似文献
128.
AtHAK5是拟南芥高亲和性钾转运体,其基因表达受低钾条件强烈诱导,编码蛋白在低钾条件下可以整合到质膜.生物信息学分析发现其氨基酸序列含有多处潜在的磷酸化位点.本研究假设这些位点对于AtHAK5的功能至关重要,为探讨AtHAK5的功能位点,分别将AtHAK5 cDNA和带有13种不同点突变位点的AtHAK5转化到athak5突变体中,获得14种稳定表达的转基因植株.利用athak5突变体根对Cs敏感的表型,最终确定T549A和T666A为非核心磷酸化位点.如下11个位点为AtHAK5功能必需位点:F85L,T86A,T311A,T359A,P551S,D552N,S603A,S604A,K668E,S698A和V713L. 相似文献
129.
Hepatocyte growth factor protects against hypoxia/reoxygenation-induced apoptosis in endothelial cells 总被引:15,自引:0,他引:15
Wang X Zhou Y Kim HP Song R Zarnegar R Ryter SW Choi AM 《The Journal of biological chemistry》2004,279(7):5237-5243
Hypoxia/reoxygenation causes cellular injury and death associated with a number of pathophysiological conditions, including myocardial ischemia/reperfusion injury and stroke. The cell death pathways induced by hypoxia/reoxygenation and their underlying regulatory mechanisms remain poorly understood. Recent studies have shown that hypoxia/reoxygenation can induce Bax translocation and cytochrome c release. Using murine lung endothelial cells as a model, we found that the induction of apoptosis by hypoxia/reoxygenation involved the activation of both Bax-dependent and death receptor-mediated pathways. We demonstrated the activation of the death-inducing signal complex and Bid pathway after hypoxia/reoxygenation. Hepatocyte growth factor markedly inhibited hypoxia/reoxygenation-induced endothelial cell apoptosis. The cytoprotection afforded by hepatocyte growth factor was mediated in part by the stimulation of FLICE-like inhibiting protein expression, the attenuation of death-inducing signal complex formation, and the inhibition of Bid and Bax activation. Hepatocyte growth factor also prevented cell injury and death by increasing the expression of the antiapoptotic Bcl-XL protein. The inhibition of Bid/Bax-induced cell death by hepatocyte growth factor primarily involved p38 MAPK and in part Akt-dependent pathways but not ERK1/ERK2. 相似文献
130.
Stefansson H Sigurdsson E Steinthorsdottir V Bjornsdottir S Sigmundsson T Ghosh S Brynjolfsson J Gunnarsdottir S Ivarsson O Chou TT Hjaltason O Birgisdottir B Jonsson H Gudnadottir VG Gudmundsdottir E Bjornsson A Ingvarsson B Ingason A Sigfusson S Hardardottir H Harvey RP Lai D Zhou M Brunner D Mutel V Gonzalo A Lemke G Sainz J Johannesson G Andresson T Gudbjartsson D Manolescu A Frigge ML Gurney ME Kong A Gulcher JR Petursson H Stefansson K 《American journal of human genetics》2002,71(4):877-892
The cause of schizophrenia is unknown, but it has a significant genetic component. Pharmacologic studies, studies of gene expression in man, and studies of mouse mutants suggest involvement of glutamate and dopamine neurotransmitter systems. However, so far, strong association has not been found between schizophrenia and variants of the genes encoding components of these systems. Here, we report the results of a genomewide scan of schizophrenia families in Iceland; these results support previous work, done in five populations, showing that schizophrenia maps to chromosome 8p. Extensive fine-mapping of the 8p locus and haplotype-association analysis, supplemented by a transmission/disequilibrium test, identifies neuregulin 1 (NRG1) as a candidate gene for schizophrenia. NRG1 is expressed at central nervous system synapses and has a clear role in the expression and activation of neurotransmitter receptors, including glutamate receptors. Mutant mice heterozygous for either NRG1 or its receptor, ErbB4, show a behavioral phenotype that overlaps with mouse models for schizophrenia. Furthermore, NRG1 hypomorphs have fewer functional NMDA receptors than wild-type mice. We also demonstrate that the behavioral phenotypes of the NRG1 hypomorphs are partially reversible with clozapine, an atypical antipsychotic drug used to treat schizophrenia. 相似文献