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To determine if the cellular factors La autoantigen (La) and polypyrimidine tract-binding protein (PTB) are required for hepatitis C virus (HCV) replication, we used siRNAs to silence these factors and then monitored their effect on HCV replication using quantitative RT-PCR. In addition, we determined the influence of PTB on the activity of the 3' noncoding region (NCR) of HCV and investigated its interaction with the components of the HCV replicase complex. We found that La is essential for efficient HCV replication while PTB appears to partially repress replication. PTB does, however, block the binding of HCV RNA-dependent RNA polymerase (RdRp, NS5B) to the 3'NCR. Indirect immunofluorescence microscopy showed co-localization of cytoplasmic PTB with the HCV RdRp in hepatoma cells (Huh-7) expressing HCV proteins, while in vitro translation of viral proteins from the HCV replicon revealed the interaction of PTB isoforms with NS5B polymerase and NS3.  相似文献   
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BackgroundAlthough recent studies have shown an association between obesity and adverse coronavirus disease 2019 (COVID-19) patient outcomes, there is a paucity in large studies focusing on hospitalized patients. We aimed to analyze outcomes associated with obesity in a large cohort of hospitalized COVID-19 patients.MethodsWe performed a retrospective study at a tertiary care health system of adult patients with COVID-19 who were admitted between March 1 and April 30, 2020. Patients were stratified by body mass index (BMI) into obese (BMI ≥ 30 kg/m 2) and non-obese (BMI < 30 kg/m 2) cohorts. Primary outcomes were mortality, intensive care unit (ICU) admission, intubation, and 30-day readmission.ResultsA total of 1983 patients were included of whom 1031 (51.9%) had obesity and 952 (48.9%) did not have obesity. Patients with obesity were younger (P < 0.001), more likely to be female (P < 0.001) and African American (P < 0.001) compared to patients without obesity. Multivariable logistic models adjusting for differences in age, sex, race, medical comorbidities, and treatment modalities revealed no difference in 60-day mortality and 30-day readmission between obese and non-obese groups. In these models, patients with obesity had increased odds of ICU admission (adjusted OR, 1.37; 95% CI, 1.07?1.76; P = 0.012) and intubation (adjusted OR, 1.37; 95% CI, 1.04?1.80; P = 0.026).ConclusionsObesity in patients with COVID-19 is independently associated with increased risk for ICU admission and intubation. Recognizing that obesity impacts morbidity in this manner is crucial for appropriate management of COVID-19 patients.  相似文献   
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In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%.  相似文献   
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Neurosurgical Review - The pathogenesis and natural history of intracranial aneurysm (IA) remains poorly understood. To this end, animal models with induced cerebral vessel lesions mimicking human...  相似文献   
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India's population has grown since independence from 350 million in 1947 to 950 million in 1997 and will probably reach 1 billion by the year 2000. Projections made from the most recent census indicate that India will be the world's most populous country by 2040. According to World Bank projections, India's population will surpass 1.7 billion by 2097. India's leaders, allocating funds to industrialization, but not enough to health care and education, failed to understand the nature and consequences of high population growth. Rapid population growth in India has led to considerable unemployment among the working-age population, considerable population pressure upon renewable and nonrenewable resources, and a demand for basic facilities which surpasses their supply. The quality of life and the environment have been adversely affected. This paper considers how investments in social development led to the achievement of replacement level fertility in Kerala, Goa, and Tamil Nadu; the sex ratio; child survival; neglect of girls; the politics of population control; and the future.  相似文献   
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