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Conjugated linoleic acid (CLA) may decrease adiposity and improve blood lipid profiles under some conditions. The goal of this study was to determine the effects of CLA supplementation on blood lipid profiles and adiposity of rats fed a diet containing a primarily saturated fat versus a diet containing a primarily unsaturated fat. Twenty-eight male Sprague-Dawley rats were randomly assigned to one of four diets containing coconut oil, coconut oil with CLA, corn oil or corn oil with CLA. After 28 days, blood was collected and serum concentrations of total cholesterol (TC), HDL-cholesterol (HDL-C), and triacylglycerols (TG) were assessed. Food intake, body weights, and epididymal fat pads were measured. No significant differences (p>0.05) were noted among groups for amount of food consumed, weight gained, food efficiency ratio or serum TG concentrations. TC concentrations were lower (p<0.05) in the CLA-supplemented rats that were fed coconut oil but not those consuming corn oil. Serum HDL-C was lower (p<0.05) in rats consuming corn oil but was not significantly different (p>0.05) for CLA supplemented groups. Epididymal fat pads weighed significantly more (p<0.05) in the coconut oil fed group compared to the corn oil fed group, but there was no significant difference (p>0.05) between the corn oil and coconut oil + CLA group. Overall, this study suggests that CLA is more beneficial for control of blood lipids and adiposity when supplemented to a diet rich in saturated versus unsaturated fat.  相似文献   
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The number of health systems strengthening (HSS) programs has increased in the last decade. However, a limited number of studies providing robust evidence for the value and impact of these programs are available. This study aims to identify knowledge gaps and challenges that impede rigorous monitoring and evaluation (M&E) of HSS, and to ascertain the extent to which these efforts are informed by existing technical guidance. Interviews were conducted with HSS advisors at United States Agency for International Development‐funded missions as well as senior M&E advisors at implementing partner and multilateral organizations. Findings showed that mission staff do not use existing technical resources, either because they do not know about them or do not find them useful. Barriers to rigorous M&E included a lack suitable of indicators, data limitations, difficulty in demonstrating an impact on health, and insufficient funding and resources. Consensus and collaboration between international health partners and local governments may mitigate these challenges. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
14.
There are relatively few molecular resources for amphibians in the tropics where widespread habitat loss, disease, and contamination threaten the world’s most diverse assemblages. We used Illumina sequencing to develop microsatellite primers for a dominant amphibian species in Costa Rica that has recently experienced population declines. We characterized 12 polymorphic loci and have provided sequences for over 200 additional primers. These novel molecular resources will be useful for future studies of population genetic structure and may help explain recent declines in one of many species that are decreasing in Central America.  相似文献   
15.
Residents of remote and Indigenous communities might experience higher exposure to some zoonotic parasites than the general North American population. Human sero-surveillance conducted in two Saulteaux communities found 113 volunteers exposed as follows: Trichinella (2.7%), Toxocara canis (4.4%), Echinococcus (4.4%), and Toxoplasma gondii (1.8%). In dogs, 41% of 51 fecal samples were positive for at least one intestinal parasite, 3% of 77 were sero-positive for Borrelia burgdorferi, and 21% of 78 for T. gondii. Echinococcus exposure was more likely to occur in non-dog owners (odds ratio [OR]: 11.4, 95% confidence interval [CI]: 1.2–107, P = 0.03); while T. canis was more likely to occur in children (ages 4–17) (OR: 49, 95% CI: 3.9–624; P = 0.003), and those with a history of dog bites (OR: 13.5, 95% CI: 1.02–179; P = 0.048). Our results emphasize the use of dogs as sentinels for emerging pathogens such as Lyme disease, and the need for targeted surveillance and intervention programs tailored for parasite species, cultural groups, and communities.  相似文献   
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IDH1 mutations in gliomas associate with longer survival. Prooxidant and antiproliferative effects of IDH1 mutations and its d-2-hydroxyglutarate (2-HG) product have been described in vitro, but inconsistently observed. It is also unclear whether overexpression of mutant IDH1 in wild-type cells accurately phenocopies the effects of endogenous IDH1-mutations on tumor apoptosis and autophagy. Herein we investigated the effects of 2-HG and mutant IDH1 overexpression on proliferation, apoptosis, oxidative stress, and autophagy in IDH1 wild-type glioma cells, and compared those results with patient-derived tumors. 2-HG reduced viability and proliferation of U87MG and LN18 cells, triggered apoptosis in LN18 cells, and autophagy in U87MG cells. In vitro studies and flank xenografts of U87MG cells overexpressing R132H IDH1 exhibited increased oxidative stress, including increases of both manganese superoxide dismutase (MnSOD) and p62. Patient-derived IDH1-mutant tumors showed no significant differences in apoptosis or autophagy, but showed p62 accumulation and actually trended toward reduced MnSOD expression. These data indicate that mutant IDH1 and 2-HG can induce oxidative stress, autophagy, and apoptosis, but these effects vary greatly according to cell type.  相似文献   
17.

Estimation of an individual’s age has important applications in forensics. In young individuals, it often relies on separate evaluations of permanent teeth (PT) and third molars (TM) development. Here, we analysed the age prediction performance of combined information from PT and TM in an unusual sample of healthy Somalis, born and living in Finland. PT development was staged according to Demirjian et al. (Hum Biol, 1973) and TM development according to Köhler et al. (Ann Anat, 1994), using panoramic radiographs from 803 subjects (397 males, 406 females) aged 3–23 years. A sex-specific Bayesian age-estimation model for the multivariate distribution of the stages conditional on age was fitted on PT, TM and PT and TM combined. The age-estimation performances were validated and quantified. The approach combining PT and TM only overestimated age with an ME of − 0.031 years in males and − 0.011 years in females, indicating the best age prediction performance.

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18.
To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD.  相似文献   
19.
Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..  相似文献   
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