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BackgroundCampylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries.MethodsThis systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations.ResultsOf the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli.ConclusionIn South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools.  相似文献   
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Background

Timing of first sex has important implications for later sexual health, but little research has considered this in populations with physical disabilities.

Objective

The purpose of this paper was to examine timing of sexual experiences among populations with physical disabilities in the United States from adolescence to early adulthood, and how timing varies by biological sex, race/ethnicity, and sexual orientation. We hypothesized that those with physical disabilities would exhibit earlier initiation of each type of sexual activity compared to those without disabilities, but the degree of differences would depend on disability severity. We further hypothesized that these associations would be moderated by biological sex, race/ethnicity, and sexual orientation.

Methods

Data were from 13,458 respondents to Waves I and IV of the National Longitudinal Study of Adolescent to Adult Health. Cox proportional hazards models assessed differences in timing of vaginal, oral, anal, and first sex by disability severity.

Results

Populations with the most severe physical disabilities had a significantly slower progression to first vaginal sex, oral sex, and their first sexual experience compared to those without disabilities (aHR: 0.74–0.77). Timing also differed by biological sex, race/ethnicity, and sexual orientation, though the direction and degree of these differences varied by disability severity.

Conclusions

Results fill an important gap in the literature by considering variations in sexual timing among populations with physical disabilities using a longitudinal, nationally representative sample. Future research should continue to promote inclusion of populations with disabilities to inform future policies and programs for healthy sexual development.  相似文献   
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Purpose

Understanding the attitudes of physicians toward the use of pre-exposure prophylaxis (PrEP) for HIV prevention among youth is critical to improving access to PrEP. We examined PrEP-related attitudes among physicians who provide primary care to 13- to 21-year-old adolescents.

Methods

Individual, in-depth, semistructured interviews were conducted with 38 physicians from adolescent medicine, family practice, internal medicine/medicine-pediatrics, obstetrics/gynecology, and pediatrics who care for any adolescents younger than 18 years. Interviews assessed familiarity with PrEP, perceived benefits and barriers to providing PrEP to adolescents, facilitating factors for prescribing PrEP, and likelihood of recommending and prescribing PrEP to adolescents.

Results

Mean age was 44.6 years (standard deviation 10.9). Fourteen physicians (37%) reported being somewhat or very familiar with PrEP. Perceived benefits of prescribing PrEP included decreased acquisition/rates of HIV, improved provision of sexual health services, and improved patient awareness of HIV risk. Barriers to PrEP were reported at the patient (e.g., lack of acceptability to patients), provider (e.g., concerns about patient adherence, safety/side effects, parents as a barrier to PrEP use), and system (e.g., high cost) levels. Facilitating factors for prescribing PrEP included low cost/coverage by insurance, physician education about PrEP, patient educational materials, and clinical guidelines for PrEP use in youth. A higher proportion of physicians reported being highly or somewhat likely to recommend (N = 16, 42%) than prescribe PrEP (N = 13, 34%).

Conclusions

In this study of primary care physician attitudes toward PrEP prescribing for adolescents, physicians identified numerous barriers to providing PrEP. Addressing these barriers may increase adolescents' access to PrEP.  相似文献   
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Circulating transthyretin (TTR) is a critical determinant of plasma retinol-binding protein 4 (RBP4) levels. Elevated RBP4 levels cause insulin resistance, and the lowering of RBP4 levels improves glucose homeostasis. Since lowering TTR levels increases renal clearance of RBP4, we determined whether decreasing TTR levels with antisense oligonucleotides (ASOs) improves glucose metabolism and insulin sensitivity in obesity. TTR-ASO treatment of mice with genetic or diet-induced obesity resulted in an 80–95% decrease in circulating levels of TTR and RBP4. Treatment with TTR-ASOs, but not control ASOs, decreased insulin levels by 30–60% and improved insulin sensitivity in ob/ob mice and high-fat diet–fed mice as early as after 2 weeks of treatment. The reduced insulin levels were sustained for up to 9 weeks of treatment and were associated with reduced adipose tissue inflammation. Body weight was not changed. TTR-ASO treatment decreased LDL cholesterol in high-fat diet–fed mice. The glucose infusion rate during a hyperinsulinemic-euglycemic clamp was increased by 50% in high-fat diet–fed mice treated with TTR-ASOs, demonstrating improved insulin sensitivity. This was also demonstrated by 20% greater inhibition of hepatic glucose production, a 45–60% increase of glucose uptake into skeletal and cardiac muscle, and a twofold increase in insulin signaling in muscle. These data show that decreasing circulating TTR levels or altering TTR-RBP4 binding could be a potential therapeutic approach for the treatment of type 2 diabetes.  相似文献   
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