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71.
72.
Women are an important audience for voluntary medical male circumcision (VMMC) communication messages so that they know that VMMC provides only partial protection against HIV. They may also be able to influence their male partners to get circumcised and practice other HIV protective measures after VMMC. This study was conducted in two phases of qualitative data collection. Phase 1 used in-depth interviews to explore women’s understanding of partial protection and their role in VMMC. Phase 2 built on the findings from the Phase 1, using focus groups to test VMMC communication messages currently used in Nyanza Province and to further explore women’s roles in VMMC. Sixty-four sexually active women between the ages of 18 and 35 participated. In Phase 1, all women said they had heard of partial protection, though some were not able to elaborate on what the concept means. When women in Phase 2 were exposed to messages about partial protection, however, participants understood the messages well and were able to identify the main points. In Phases 1 and 2, many participants said that they had discussed VMMC with their partner, and for several, it was a joint decision for the man to go for VMMC. These findings suggest that current VMMC messaging is reaching women, though communications could more effectively target women to increase their ability to communicate about partial HIV protection from VMMC. Also, women seem to be playing an important role in encouraging men to get circumcised, so reaching out to women could be a valuable intervention strategy for increasing VMMC uptake and promoting use of other HIV protective measures after VMMC. 相似文献
73.
Matthew J. Wirick Allison R. Cale Isaac T. Smith Amelia F. Alessi Margaret R. Starostik Liberta Cuko Kyal Lalk Mikayla N. Schmidt Benjamin S. Olson Payton M. Salomon Alexis Santos Axel Schmitter-Snchez Himani Galagali Kevin J. Ranke Payton A. Wolbert Macy L. Knoblock John K. Kim Xantha Karp 《PLoS genetics》2021,17(11)
74.
Early mitochondrial abnormalities in hippocampal neurons cultured from Fmr1 pre‐mutation mouse model
Susan Hulsizer Flora Tassone Robert F. Berman Paul J. Hagerman Isaac N. Pessah 《Journal of neurochemistry》2012,123(4):613-621
Pre‐mutation CGG repeat expansions (55–200 CGG repeats; pre‐CGG) within the fragile‐X mental retardation 1 (FMR1) gene cause fragile‐X‐associated tremor/ataxia syndrome in humans. Defects in neuronal morphology, early migration, and electrophysiological activity have been described despite appreciable expression of fragile‐X mental retardation protein (FMRP) in a pre‐CGG knock‐in (KI) mouse model. The triggers that initiate and promote pre‐CGG neuronal dysfunction are not understood. The absence of FMRP in a Drosophila model of fragile‐X syndrome was shown to increase axonal transport of mitochondria. In this study, we show that dissociated hippocampal neuronal culture from pre‐CGG KI mice (average 170 CGG repeats) express 42.6% of the FMRP levels and 3.8‐fold higher Fmr1 mRNA than that measured in wild‐type neurons at 4 days in vitro. Pre‐CGG hippocampal neurons show abnormalities in the number, mobility, and metabolic function of mitochondria at this early stage of differentiation. Pre‐CGG hippocampal neurites contained significantly fewer mitochondria and greatly reduced mitochondria mobility. In addition, pre‐CGG neurons had higher rates of basal oxygen consumption and proton leak. We conclude that deficits in mitochondrial trafficking and metabolic function occur despite the presence of appreciable FMRP expression and may contribute to the early pathophysiology in pre‐CGG carriers and to the risk of developing clinical fragile‐X‐associated tremor/ataxia syndrome. 相似文献
75.
Background
Single Nucleotide Polymorphisms (SNPs) are an increasingly important tool for genetic and biomedical research. Although current genomic databases contain information on several million SNPs and are growing at a very fast rate, the true value of a SNP in this context is a function of the quality of the annotations that characterize it. Retrieving and analyzing such data for a large number of SNPs often represents a major bottleneck in the design of large-scale association studies. 相似文献76.
Sergio Regodón Asunción Ramos María P Míguez Antonio Carrillo-Vico Juan A Rosado Isaac Jardín 《BMC veterinary research》2012,8(1):1-8
Background
Eradication of bovine tuberculosis (bTB) through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12?year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient (??) depending on the herd-type (beef/dairy/bullfighting). In addition, the probability to recover the officially bTB free (OTF) status in infected herds depending on the type of herd and the diagnostic strategy implemented was assessed using Cox proportional hazard models.Results
Overall, dairy herds showed higher ?? (median 4.7) than beef or bullfighting herds (2.3 and 2.2 respectively). Introduction of interferon-gamma (IFN-??) as an ancillary test produced an apparent increase in the ?? coefficient regardless of production type, likely due to an increase in diagnostic sensitivity. Time to recover OTF status was also significantly lower in dairy herds, and length of bTB episodes was significantly reduced when the IFN-?? was implemented to manage the outbreak.Conclusions
Our results suggest that bTB spreads more rapidly in dairy herds compared to other herd types, a likely cause being management and demographic-related factors. However, outbreaks in dairy herds can be controlled more rapidly than in typically extensive herd types. Finally, IFN-?? proved its usefulness to rapidly eradicate bTB at a herd-level. 相似文献77.
Vicenç Méndez Isaac Llopis Daniel Campos Werner Horsthemke 《Theoretical population biology》2010,77(4):250-256
We determine the critical patch size below which extinction occurs for populations living in one-dimensional habitats surrounded by completely hostile environments in the presence of environmental fluctuations. The population dynamics is reformulated in terms of a stochastic reaction–diffusion equation and is reduced to a deterministic equation that incorporates the systematic contributions of the noise. We obtain bifurcation diagrams and relations for the mean population density at the stationary state, the critical patch size, and the mean number of individuals in the habitat. The effect of the noise differs, depending on whether it affects the net growth rate or the intraspecific competition term. Fluctuations in the net growth rate decrease the critical patch size, whereas fluctuations in the competition term do not change the critical patch size. We compare our analytical results with numerical solutions of the stochastic partial differential equations and show that our procedure proves useful in dealing with reaction–diffusion equations with multiplicative noise. 相似文献
78.
Tania Massignan Richard S. Stewart Emiliano Biasini Isaac H. Solomon Valentina Bonetto Roberto Chiesa David A. Harris 《The Journal of biological chemistry》2010,285(10):7752-7765
In prion diseases, the infectious isoform of the prion protein (PrPSc) may subvert a normal, physiological activity of the cellular isoform (PrPC). A deletion mutant of the prion protein (Δ105–125) that produces a neonatal lethal phenotype when expressed in transgenic mice provides a window into the normal function of PrPC and how it can be corrupted to produce neurotoxic effects. We report here the surprising and unexpected observation that cells expressing Δ105–125 PrP and related mutants are hypersensitive to the toxic effects of two classes of antibiotics (aminoglycosides and bleomycin analogues) that are commonly used for selection of stably transfected cell lines. This unusual phenomenon mimics several essential features of Δ105–125 PrP toxicity seen in transgenic mice, including rescue by co-expression of wild type PrP. Cells expressing Δ105–125 PrP are susceptible to drug toxicity within minutes, suggesting that the mutant protein enhances cellular accumulation of these cationic compounds. Our results establish a screenable cellular phenotype for the activity of neurotoxic forms of PrP, and they suggest possible mechanisms by which these molecules could produce their pathological effects in vivo. 相似文献
79.
FCRL5 Delineates Functionally Impaired Memory B Cells Associated with Plasmodium falciparum Exposure
80.
Kabemba E. Mwape Joachim Blocher Jasmin Wiefek Kathie Schmidt Pierre Dorny Nicolas Praet Clarance Chiluba Holger Schmidt Isaac K. Phiri Andrea S. Winkler Sarah Gabri?l 《PLoS neglected tropical diseases》2015,9(8)
Zambia is endemic for Taenia solium taeniosis and cysticercosis. In this single-centered, cross-sectional, community-based study, the role of neurocysticercosis (NCC) as a cause of epilepsy was examined. People with epilepsy (PWE, n = 56) were identified in an endemic area using a screening questionnaire followed by in-depth interviews and neurological examination. Computed tomography (CT) was performed on 49 people with active epilepsy (PWAE) and their sera (specific antibody and antigen detection, n = 56) and stools (copro-antigen detection, n = 54) were analyzed. The CT scan findings were compared to a group of 40 CT scan controls. Of the PWE, 39.3% and 23.2% were positive for cysticercal antibodies and antigens, respectively, and 14.8% for coproantigens (taeniosis). Lesions highly suggestive of NCC were detected in 24.5% and definite NCC lesions in 4.1% of CT scans of PWAE. This compares to 2.5% and 0%, respectively, in the control CT scans. Using the Del Brutto diagnostic criteria, 51.8% of the PWAE were diagnosed with probable or definitive NCC and this rose to 57.1% when the adapted criteria, as proposed by Gabriël et al. (adding the sero-antigen ELISA test as a major criterion), were used. There was no statistically significant relationship between NCC, current age, age at first seizure and gender. This study suggests that NCC is the single most important cause of epilepsy in the study area. Additional large-scale studies, combining a community based prevalence study for epilepsy with neuroimaging and serological analysis in different areas are needed to estimate the true impact of neurocysticercosis in endemic regions and efforts should be instituted to the control of T. solium. 相似文献