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Malawi has successfully leveraged multiple delivery platforms to scale-up and sustain the implementation of preventive chemotherapy (PCT) for the control of morbidity caused by soil-transmitted helminths (STH). Sentinel monitoring demonstrates this strategy has been successful in reducing STH infection in school-age children, although our understanding of the contemporary epidemiological profile of STH across the broader community remains limited. As part of a multi-site trial evaluating the feasibility of interrupting STH transmission across three countries, this study aimed to describe the baseline demographics and the prevalence, intensity and associated risk factors of STH infection in Mangochi district, southern Malawi. Between October-December 2017, a community census was conducted across the catchment area of seven primary healthcare facilities, enumerating 131,074 individuals across 124 villages. A cross-sectional parasitological survey was then conducted between March-May 2018 in the censused area as a baseline for a cluster randomised trial. An age-stratified random sample of 6,102 individuals were assessed for helminthiasis by Kato-Katz and completed a detailed risk-factor questionnaire. The age-cluster weighted prevalence of any STH infection was 7.8% (95% C.I. 7.0%-8.6%) comprised predominantly of hookworm species and of entirely low-intensity infections. The presence and intensity of infection was significantly higher in men and in adults. Infection was negatively associated with risk factors that included increasing levels of relative household wealth, higher education levels of any adult household member, current school attendance, or recent deworming. In this setting of relatively high coverage of sanitation facilities, there was no association between hookworm and reported access to sanitation, handwashing facilities, or water facilities. These results describe a setting that has reduced the prevalence of STH to a very low level, and confirms many previously recognised risk-factors for infection. Expanding the delivery of anthelmintics to groups where STH infection persist could enable Malawi to move past the objective of elimination of morbidity, and towards the elimination of STH.Trial registration: NCT03014167.  相似文献   
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In an effort to better utilize published evidence obtained from animal experiments, systematic reviews of preclinical studies are increasingly more common—along with the methods and tools to appraise them (e.g., SYstematic Review Center for Laboratory animal Experimentation [SYRCLE’s] risk of bias tool). We performed a cross-sectional study of a sample of recent preclinical systematic reviews (2015–2018) and examined a range of epidemiological characteristics and used a 46-item checklist to assess reporting details. We identified 442 reviews published across 43 countries in 23 different disease domains that used 26 animal species. Reporting of key details to ensure transparency and reproducibility was inconsistent across reviews and within article sections. Items were most completely reported in the title, introduction, and results sections of the reviews, while least reported in the methods and discussion sections. Less than half of reviews reported that a risk of bias assessment for internal and external validity was undertaken, and none reported methods for evaluating construct validity. Our results demonstrate that a considerable number of preclinical systematic reviews investigating diverse topics have been conducted; however, their quality of reporting is inconsistent. Our study provides the justification and evidence to inform the development of guidelines for conducting and reporting preclinical systematic reviews.

A cross sectional study of a sample of recent preclinical systematic reviews reveals deficiencies in reporting and provides the justification and evidence to inform the development of specific guidelines for conducting and reporting preclinical systematic reviews.  相似文献   
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ObjectiveTo determine the optimal insulin-to-steroid dose ratio for the attainment of glycemic control in hospitalized patients.MethodsWe retrospectively studied data collected from the electronic health records within an academic medical center from 18 599 patient-days where patients were treated concurrently with insulin and steroids. Multivariate logistic regression analyses, which included demographic and clinical variables, were performed to assess the relationships between the exposures of total and basal insulin-to-steroid ratios and the outcomes of glycemic control (all blood glucose readings on the following patient-day were >70 and ≤180 mg/dL) and hypoglycemia within 3 subgroups of steroid dosing: low (≤10-mg prednisone equivalent dose [PED]), medium (from >10-mg to ≤40-mg PED), and high (>40-mg PED).ResultsIncreased insulin-to-steroid ratio was associated with increased odds of both glycemic control and hypoglycemia. The optimal total insulin-to-steroid ratio for attaining glycemic control was 0.294 U/kg/10-mg PED in the low-dose subgroup, 0.257 U/kg/10-mg PED in the medium-dose subgroup, and 0.085 U/kg/10-mg PED in the high-dose subgroup. The optimal basal insulin-to-steroid ratio was 0.215 U/kg/10-mg PED in the low-dose subgroup, 0.126 U/kg/10-mg PED in the medium-dose subgroup, and 0.036 U/kg/10-mg PED in the high-dose subgroup.ConclusionIncreasing insulin-to-steroid ratios are positively associated with glycemic control and hypoglycemia. Our study suggests that approximately 0.3 U/kg/10-mg PED is an optimal dose for low- and medium-dose steroids, whereas approximately 0.1 U/kg/10-mg PED is an optimal dose for high-dose steroids. Further prospective studies are needed to identify insulin regimens that will optimize glycemic control in steroid-treated patients while minimizing the risk of hypoglycemia.  相似文献   
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Epidermal Leydig cells observed in the ventral epidermis of Salamandra salamandra larvae from birth until metamorphosis are characterized by large vesicles and a supporting Langerhans net. They decline in number after birth and disappear entirely after metamorphosis. The cells change in structure and become larger, thus indicating a process of degeneration. The Leydig cells are continuously removed by macrophagelike cells after birth.  相似文献   
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Heme-containing polypeptides can be detected on sodium dodecylsulphate (SDS)-polyacrylamide gels by the intrinsic fluorescence of their prosthetic group. The fluorescence is stable and specific; approximately 0.2 μg of cytochrome c/band can be detected in this way. No equipment is necessary beyond a camera, an ultraviolet lamp, and some filters.  相似文献   
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