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Three-dimensional models of the GDP and GTP forms of the guanine nucleotide domain of Escherichia coli elongation factor Tu 总被引:1,自引:0,他引:1
Three-dimensional models of the GDP and GTP forms of the guanine nucleotide domain of Escherichia coli elongation factor Tu have been derived from the atomic coordinates of the trypsin-modified form of EF-Tu-GDP and by comparison with the ras p21 structures. The significance of the differences in the guanine nucleotide binding sites of EF-Tu and ras p21 are discussed. Crystallization of the EF-Tu-GMPPNP complex is reported. 相似文献
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Laura Noël-Romas Michelle Perner Refilwe Molatlhegi Christina Farr Zuend Amanda Mabhula Sarah Hoger Alana Lamont Kenzie Birse Alicia Berard Stuart McCorrister Garett Westmacott Al Leslie Vanessa Poliquin Renee Heffron Lyle R. McKinnon Adam D. Burgener 《PLoS pathogens》2020,16(12)
Alterations to the mucosal environment of the female genital tract, such as genital inflammation, have been associated with increased HIV acquisition in women. As the microbiome and hormonal contraceptives can affect vaginal mucosal immunity, we hypothesized these components may interact in the context of HIV susceptibility. Using previously published microbiome data from 685 women in the CAPRISA-004 trial, we compared relative risk of HIV acquisition in this cohort who were using injectable depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN), and combined oral contraceptives (COC). In women who were Lactobacillus-dominant, HIV acquisition was 3-fold higher in women using DMPA relative to women using NET-EN or COC (OR: 3.27; 95% CI: 1.24–11.24, P = 0.0305). This was not observed in non-Lactobacillus-dominant women (OR: 0.95, 95% CI: 0.44–2.15, P = 0.895) (interaction P = 0.0686). Higher serum MPA levels associated with increased molecular pathways of inflammation in the vaginal mucosal fluid of Lactobacillus-dominant women, but no differences were seen in non-Lactobacillus dominant women. This study provides data suggesting an interaction between the microbiome, hormonal contraceptives, and HIV susceptibility. 相似文献
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Mark Q Benedict Bart GJ Knols Hervé C Bossin Paul I Howell Eric Mialhe Carlos Caceres Alan S Robinson 《Malaria journal》2009,8(Z2):S4
Mosquitoes, just as other insects produced for the sterile insect technique (SIT), are subjected to several unnatural processes including laboratory colonisation and large-scale factory production. After these processes, sterile male mosquitoes must perform the natural task of locating and mating with wild females. Therefore, the colonisation and production processes must preserve characters necessary for these functions. Fortunately, in contrast to natural selection which favours a suite of characteristics that improve overall fitness, colonisation and production practices for SIT strive to maximize only the few qualities that are necessary to effectively control populations.However, there is considerable uncertainty about some of the appropriate characteristics due to the lack of data. Development of biological products for other applications suggest that it is possible to identify and modify competitiveness characteristics in order to produce competitive mass produced sterile mosquitoes. This goal has been pursued - and sometimes achieved - by mosquito colonisation, production, and studies that have linked these characteristics to field performance. Parallels are drawn to studies in other insect SIT programmes and aquaculture which serve as vital technical reference points for mass-production of mosquitoes, most of whose development occurs - and characteristics of which are determined - in an aquatic environment. Poorly understood areas that require further study are numerous: diet, mass handling and genetic and physiological factors that influence mating competitiveness. Compromises in such traits due to demands to increase numbers or reduce costs, should be carefully considered in light of the desired field performance. 相似文献
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A sequence of deoxyribonucleic acid of 2.7 times 10-6 to 3.3 times 10-6 daltons which includes the TEM beta-lactamase gene is present on the small plasmid RSF 1030 (R-Amp). This same sequence is present on plasmid derivatives that have received a translocation of deoxyribonucleic acid specifying the TEM beta-lactamase and is also present on naturally occurring plasmids of the F1, F11, N, X, O, I, C, and W incompatibility groups that do not specify ampicillin resistance or specify O-type beta-lactamases. 相似文献
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Jared M. Baeten Renee Heffron Lara Kidoguchi Nelly R. Mugo Elly Katabira Elizabeth A. Bukusi Stephen Asiimwe Jessica E. Haberer Jennifer Morton Kenneth Ngure Nulu Bulya Josephine Odoyo Edna Tindimwebwa Craig Hendrix Mark A. Marzinke Norma C. Ware Monique A. Wyatt Susan Morrison Harald Haugen Andrew Mujugira Deborah Donnell Connie Celum Partners Demonstration Project Team 《PLoS medicine》2016,13(8)
BackgroundAntiretroviral-based interventions for HIV-1 prevention, including antiretroviral therapy (ART) to reduce the infectiousness of HIV-1 infected persons and pre-exposure prophylaxis (PrEP) to reduce the susceptibility of HIV-1 uninfected persons, showed high efficacy for HIV-1 protection in randomized clinical trials. We conducted a prospective implementation study to understand the feasibility and effectiveness of these interventions in delivery settings.ConclusionsIntegrated delivery of time-limited PrEP until sustained ART use in African HIV-1-serodiscordant couples was feasible, demonstrated high uptake and adherence, and resulted in near elimination of HIV-1 transmission, with an observed HIV incidence of <0.5% per year compared to an expected incidence of >5% per year. 相似文献