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Cryptosporidiosis is a rapidly emerging disease in the tropics. This is the first report of Cryptosporidium and other protozoan infections (Entamoeba spp., Iodamoeba, Chilomastix, and Balantidium spp.) in wild primates that inhabit the natural forest of Sri Lanka. It is unclear if non-human primates serve as a reservoir for these parasites under certain conditions. A cross-sectional coprologic survey among 125 monkeys (89 toque macaques, 21 gray langurs, and 15 purple-faced langurs) indicated that Cryptosporidium was detected in all three primate species and was most common among monkeys using areas and water that had been heavily soiled by human feces and livestock. Most macaques (96%) shedding Cryptosporidium oocysts were co-infected with other protozoans and important anthropozoonotic gastrointestinal parasites (e.g., Enterobius and Strongyloides). The transmission of these parasites among primates in the wild may have important implications for public health as well as wildlife conservation management.  相似文献   
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Trauma is associated with an increased likelihood of experiencing suicidality, indicating the need for and potential value of trauma-informed suicide prevention strategies. The aim of this study is to systematically review published literature regarding trauma-informed approaches for suicide prevention, and the impact on suicide outcomes. Systematic searches were conducted in eight databases (Medline, Embase, PsycInfo, Emcare, Nursing, and JBI in the Ovid platform; as well as ProQuest Psychology Database and The Cochrane Library) in March 2022, with no publication date limit. Four studies met the inclusion criteria: two randomized controlled trials and two quasi-experimental studies. Two studies reported reductions in ideation, intent, and behaviour among youth and a cultural minority group. Few studies directly reporting suicide outcomes were identified, all were quantitative, and heterogeneity prevents generalizability across population groups. Currently, there is limited evidence focusing specifically on trauma-informed suicide prevention across the lifespan. Additional research, incorporating lived experience voices, is needed to understand the potential of this approach, as well as how mental health nurses can incorporate these approaches into their practice.  相似文献   
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DC-SIGN is a C-type lectin receptor on antigen presenting cells (dendritic cells) which has an important role in some viral infection, notably by HIV and Dengue virus (DV). Multivalent presentation of carbohydrates on dendrimeric scaffolds has been shown to inhibit DC-SIGN binding to HIV envelope glycoprotein gp120, thus blocking viral entry. This approach has interesting potential applications for infection prophylaxis. In an effort to develop high affinity inhibitors of DC-SIGN mediated viral entry, we have synthesized a group of glycodendrimers of different valency that bear different carbohydrates or glycomimetic DC-SIGN ligands and have studied their DC-SIGN binding activity and antiviral properties both in an HIV and a Dengue infection model. Surface Plasmon Resonance (SPR) competition studies have demonstrated that the materials obtained bind efficiently to DC-SIGN with IC50s in the μm range, which depend on the nature of the ligand and on the valency of the scaffold. In particular, a hexavalent presentation of the DC-SIGN selective antagonist 4 displayed high potency, as well as improved accessibility and chemical stability relative to previously reported dendrimers. At low μm concentration the material was shown to block both DC-SIGN mediated uptake of DV by Raji cells and HIV trans-infection of T cells.  相似文献   
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African Americans are admixed with genetic contributions from European and African ancestral populations. Admixture mapping leverages this information to map genes influencing differential disease risk across populations. We performed admixture and association mapping in 3,300 African American current or former smokers from the COPDGene Study. We analyzed estimated local ancestry and SNP genotype information to identify regions associated with FEV1/FVC, the ratio of forced expiratory volume in one second to forced vital capacity, measured by spirometry performed after bronchodilator administration. Global African ancestry inversely associated with FEV1/FVC (P = 0.035). Genome‐wide admixture analysis, controlling for age, gender, body mass index, current smoking status, pack‐years smoked, and four principal components summarizing the genetic background of African Americans in the COPDGene Study, identified a region on chromosome 12q14.1 associated with FEV1/FVC (P = 2.1 × 10?6) when regressed on local ancestry. Allelic association in this region of chromosome 12 identified an intronic variant in FAM19A2 (rs348644) as associated with FEV1/FVC (P = 1.76 × 10?6). By combining admixture and association mapping, a marker on chromosome 12q14.1 was identified as being associated with reduced FEV1/FVC ratio among African Americans in the COPDGene Study.  相似文献   
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Acquired immunodeficiency syndrome patients face great socio-economic difficulties in obtaining treatment. There is an urgent need for new, safe, and cheap anti-HIV agents. Traditional medicinal plants are a valuable source of novel anti-HIV agents and may offer alternatives to expensive medicines in future. Various medicinal plants or plant-derived natural products have shown strong anti-HIV activity and are under various stages of clinical development in different parts of the world. The present study was directed towards assessment of anti-HIV activity of various extracts prepared from Indian medicinal plants. The plants were chosen on the basis of similarity of chemical constituents with reported anti-HIV compounds or on the basis of their traditional usage as immunomodulators. Different extracts were prepared by Soxhlet extraction and liquid-liquid partitioning. Ninety-two extracts were prepared from 23 plants. Anti-HIV activity was measured in a human CD4+ T-cell line, CEM-GFP cells infected with HIV-1NL4.3. Nine extracts of 8 different plants significantly reduced viral production in CEM-GFP cells infected with HIV-1NL4.3. Aegle marmelos, Argemone mexicana, Asparagus racemosus, Coleus forskohlii, and Rubia cordifolia demonstrated promising anti-HIV potential and were investigated for their active principles.  相似文献   
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Admixture is a potential source of confounding in genetic association studies, so it becomes important to detect and estimate admixture in a sample of unrelated individuals. Populations of African descent in the US and the Caribbean share similar historical backgrounds but the distributions of African admixture may differ. We selected 416 ancestry informative markers (AIMs) to estimate and compare admixture proportions using STRUCTURE in 906 unrelated African Americans (AAs) and 294 Barbadians (ACs) from a study of asthma. This analysis showed AAs on average were 72.5% African, 19.6% European and 8% Asian, while ACs were 77.4% African, 15.9% European, and 6.7% Asian which were significantly different. A principal components analysis based on these AIMs yielded one primary eigenvector that explained 54.04% of the variation and captured a gradient from West African to European admixture. This principal component was highly correlated with African vs. European ancestry as estimated by STRUCTURE (r2=0.992, r2=0.912, respectively). To investigate other African contributions to African American and Barbadian admixture, we performed PCA on ∼14,000 (14k) genome‐wide SNPs in AAs, ACs, Yorubans, Luhya and Maasai African groups, and estimated genetic distances (FST). We found AAs and ACs were closest genetically (FST=0.008), and both were closer to the Yorubans than the other East African populations. In our sample of individuals of African descent, ∼400 well‐defined AIMs were just as good for detecting substructure as ∼14,000 random SNPs drawn from a genome‐wide panel of markers. Genet. Epidemiol. 34:561–568, 2010.© 2010 Wiley‐Liss, Inc.  相似文献   
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Studies have shown an association between the lipoprotein lipase gene and dyslipidemia and atherosclerosis in some populations. The aim of this study was to investigate the association between the common lipoprotein lipase HindIII (T-G) and Ser447Ter (C-G) polymorphisms with dyslipidemia in Asian Indians, who are known to have very high rates of premature coronary artery disease. A total of 1,015 subjects, comprising 550 normal glucose-tolerant subjects and 465 patients with type 2 diabetes, were randomly selected from the Chennai Urban Rural Epidemiology Study. The total serum cholesterol, high-density lipoprotein (HDL) cholesterol, and serum triglyceride levels were assayed using enzymatic methods. Low-density lipoprotein cholesterol was calculated using the Friedewald formula. Genotyping was done using the polymerase chain reaction-restriction fragment length polymorphism method. A significant association was found between the H+ allele of HindIII with low HDL cholesterol and elevated triglyceride levels. The Ser allele of Ser447Ter was also strongly associated with low HDL cholesterol levels. No association was found between the H+ allele and Ser Allele with the total or low-density lipoprotein cholesterol levels. Group-wise haplotype frequencies were generated using the expectation-maximization algorithm to detect differences in overall haplotype frequency profiles between the case-control groups. The haplotype analysis showed that the H+ Ser and H- Ter were the "high-risk" and "low-risk" haplotypes for low HDL cholesterol and elevated triglyceride levels, respectively. In conclusion, the H+ Ser haplotype of the lipoprotein lipase gene was associated with low HDL cholesterol levels and hypertriglyceridemia in Asian Indians.  相似文献   
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