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With the development of insulin resistance (IR), there is a compensatory increase in the plasma insulin response to offset the defect in insulin action to maintain normal glucose tolerance. The insulin response is the result of two factors: insulin secretion and metabolic clearance rate of insulin (MCRI). Subjects (104 with normal glucose tolerance [NGT], 57 with impaired glucose tolerance [IGT], and 207 with type 2 diabetes mellitus [T2DM]), divided in nonobese and obese groups, received a euglycemic insulin-clamp (40 mU/m2 ⋅ min) and an oral glucose tolerance test (OGTT) (75 g) on separate days. MCRI was calculated during the insulin-clamp performed with [3-3H]glucose and the OGTT and related to IR: peripheral (glucose uptake during the insulin clamp), hepatic (basal endogenous glucose production × fasting plasma insulin [FPI]), and adipocyte (fasting free fatty acid × FPI). MCRI during the insulin clamp was reduced in obese versus nonobese NGT (0.60 ± 0.03 vs. 0.73 ± 0.02 L/min ⋅ m2, P < 0.001), in nonobese IGT (0.62 ± 0.02, P < 0.004), and in nonobese T2DM (0.68 ± 0.02, P < 0.03). The MCRI during the insulin clamp was strongly and inversely correlated with IR (r = −0.52, P < 0.0001). During the OGTT, the MCRI was suppressed within 15–30 min in NGT and IGT subjects and remained suppressed. In contrast, suppression was minimal in T2DM. In conclusion, the development of IR in obese subjects is associated with a decline in MCRI that represents a compensatory response to maintain normal glucose tolerance but is impaired in individuals with T2DM.  相似文献   
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This study aimed to determine the seroprevalence and determinants of hepatitis B virus (HBV) infection among university students in Bangladesh. This cross-sectional study was conducted among 614 students from five universities in central Bangladesh. Data were collected on demographic information, immunization history, medical and blood transfusion history through the face-to-face interview. Blood samples were collected and screened for anti-HBsAg using ELISA, HBsAg Rapid Test-cassette, and immune chromatographic test. The overall seroprevalence of HBV infection was 5.0%, and vaccination coverage was 19.2% among the participants. Students having a history of surgery (OR 11.004, 95% CI 3.211–37.707), blood transfusion (OR 5.651, 95% CI 0.965–33.068), being married (OR 4.776, 95% CI 1.508–15.127), and not being vaccinated (OR 9.825, 95% CI 1.130–85.367) were at higher risk of being infected by HBV. This study showed the endemicity of HBV infection among the Bangladeshi population. Marriage, surgical or blood transfusion history, not being vaccinated were the determinants of HBV infection within the study population. Public health initiatives for preventing HBV infection at the university levels should be envisaged.

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ObjectiveTo assess health equity-oriented COVID-19 reporting across Canadian provinces and territories, using a scorecard approach.MethodsA scan was performed of provincial and territorial reporting of five data elements (cumulative totals of tests, cases, hospitalizations, deaths, and population size) across three units of aggregation (province or territory level, health regions, and local areas) (15 “overall” indicators), and for four vulnerable settings (long-term care and detention facilities, schools, and homeless shelters) and eight social markers (age, sex, immigration status, race/ethnicity, healthcare worker status, occupational sector, income, and education) (180 “equity-related” indicators) as of December 31, 2020. Per indicator, one point was awarded if case-delimited data were released, 0.7 points if only summary statistics were reported, and 0 if neither was provided. Results were presented using a scorecard approach.ResultsOverall, information was more complete for cases and deaths than for tests, hospitalizations, and population size denominators needed for rate estimation. Information provided on jurisdictions and their regions, overall, tended to be more available (average score of 58%, “D”) than that for equity-related indicators (average score of 17%, “F”). Only British Columbia, Alberta, and Ontario provided case-delimited data, with Ontario and Alberta providing case information for local areas. No jurisdiction reported on outcomes according to patients’ immigration status, race/ethnicity, income, or education. Though several provinces reported on cases in long-term care facilities, only Ontario and Quebec provided detailed information for detention facilities and schools, and only Ontario reported on cases within homeless shelters and across occupational sectors.ConclusionOne year into the pandemic, socially stratified reporting for COVID-19 outcomes remains sparse in Canada. However, several “best practices” in health equity-oriented reporting were observed and set a relevant precedent for all jurisdictions to follow for this pandemic and future ones.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00496-6.  相似文献   
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IntroductionPolio, which is caused by poliovirus, is a contagious, potentially crippling, and deadly disease. Pakistan is one of the countries in which polio is still endemic in the 21st century. In 2019, 146 polio cases were reported across the country with some resulting in deaths. Following the spread of rumors insinuating that children were falling sick after receiving an anti-polio vaccine, a mob attacked and set fire to a small hospital in the Peshawar district in April 2019. The present study investigates readers’ discussions that emerged from Dawn’s online readers’ comments on polio-related news stories in Pakistan.MethodsUsing thematic analysis, we analyzed (N = 2216) comments made by readers in the polio-related news stories published on Dawn.com from January 1, 2012, to March 1, 2020.ResultsSeven major themes emerged from the analysis of the comments: 1) reasons for and challenges resulting in the failure to eradicate polio; 2) proposed solutions and policy changes to eradicate polio; 3) misinformation; 4) criticism, frustration, and shame; 5) comparison of Pakistan to other countries; 6) the internet as a public sphere; 7) suffering, empathy, and appreciation. Overall, our findings suggested that commenters are knowledgeable about polio vaccines and consider polio a serious threat to public health in Pakistan.ConclusionOur study not only validated previous study findings such as reasons, challenges, and issues related to polio vaccination, but also found new challenges in online news sites concerning misinformation on polio and polio vaccination in Pakistan.  相似文献   
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This paper highlights a series of studies using the male rhesus monkey that has led to a model for the control of the onset of puberty in higher primates. The model proposes that the timing of puberty in these species is governed by the duration of a central brake that, during juvenile development, holds in check the hypothalamic network of gonadotropin-releasing hormone (GnRH) neurons, which, in the adult, drive the pituitary-gonadal axis. The neurobiology of this hypothalamic brake, and the physiological mechanisms that time its application and removal, are incompletely understood. Nevertheless, the pubertal resurgence of pulsatile GnRH release, which terminates the juvenile phase of primate development and triggers the initiation of puberty in man and monkeys, is associated with structural and molecular remodeling of the hypothalamus. A major component of this developmental plasticity appears to involve neuropeptide Y (NPY). NPY inhibits GnRH release, and NPY gene expression in the hypothalamus is elevated during juvenile development when GnRH release is restrained. Since the changes in hypothalamic function and morphology that trigger primate puberty unfold in the absence of gonadal steroid feedback, the possibility is raised that, in addition to activating the pituitary-gonadal axis at this stage of development, they may also contribute directly to the causation of behaviors and affective states that emerge at adolescence.  相似文献   
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