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1.
A software system for transforming fragments from four-color fluorescence-based gel electrophoresis experiments into assembled sequence is described. It has been developed for large-scale processing of all trace data, including shotgun and finishing reads, regardless of clone origin. Design considerations are discussed in detail, as are programming implementation and graphic tools. The importance of input validation, record tracking, and use of base quality values is emphasized. Several quality analysis metrics are proposed and applied to sample results from recently sequenced clones. Such quantities prove to be a valuable aid in evaluating modifications of sequencing protocol. The system is in full production use at both the Genome Sequencing Center and the Sanger Centre, for which combined weekly production is ~100,000 sequencing reads per week.  相似文献   
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An assay that uses heminested PCR-restriction fragment length polymorphism analysis for the detection and genotyping of Giardia duodenalis on the basis of polymorphism in the triose phosphate isomerase (tpi) gene was developed. This assay was evaluated with DNA extracted from purified parasite material, bacterial cultures, whole human feces containing G. duodenalis and other parasites, and their corresponding immunofluorescence-stained fecal smears on glass microscope slides. The assay was specific and discriminated between G. duodenalis assemblages A and B. RFLP analysis further distinguished two groups (designated groups I and II) within assemblage A. Among 35 DNA samples extracted from whole feces from patients with confirmed sporadic giardiasis, the tpi gene was amplified from 33 (94%). Of these, nine (27%) samples contained assemblage A group II, 21 (64%) contained assemblage B, and 3 (9%) contained a mixture of assemblage A group II and assemblage B. The tpi gene of G. duodenalis assemblage B was amplified from 21 of 24 (88%) DNA samples extracted from whole feces from patients with confirmed cases of infection in a nursery outbreak. No amplification was detected from the remaining three DNA samples. Overall, analysis of DNA extracted from material recovered from stained microscope slides identified identical G. duodenalis genotypes in 35 (65%) of the 54 samples for which a genotype was established with DNA from whole feces. The heminested PCR method developed is sensitive, simple, and rapid to perform and is applicable for the analysis of other intestinal pathogens.  相似文献   
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BACKGROUND: There is continuing controversy about how age affects depression and anxiety, with a lack of consistent results across studies. Two reasons for this inconsistency are age bias in measures and different patterns of exposure to risk factors across age groups in various studies. METHOD: Data on anxiety and depression symptoms were collected in a community survey of 7485 persons aged 20-24, 40-44 or 60-64 years. These measures were investigated for factorial invariance across age groups. Data were also collected on a wide range of potential risk factors, including social, physical health and personal factors, with the aim of determining whether these factors might partly or wholly account for age group differences. RESULTS: The invariance of correlated latent factors representing anxiety and depression was examined across age groups, and a generalized measure of psychological distress was computed. Depression, anxiety and psychological distress showed a decline across age groups for females and a decline from 40-44 to 60-64 years for males. Some of these age differences were accounted for by other risk factors, with the most important being recent crises at work and negative social relationships with family and friends. CONCLUSION: Psychological distress generally declined across the age range 20-64 years and this was not attributable to measurement bias. Differential exposure to risk factors explained some, but not all, of the age group difference. Therefore other mechanisms that explain the lower level of distress in older age groups remain to be identified.  相似文献   
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The identification of specific genetic loci that contribute to inflammatory and autoimmune diseases has proved difficult due to the contribution of multiple interacting genes, the inherent genetic heterogeneity present in human populations, and a lack of new mouse mutants. By using N-ethyl-N-nitrosourea (ENU) mutagenesis to discover new immune regulators, we identified a point mutation in the murine phospholipase Cg2 (Plcg2) gene that leads to severe spontaneous inflammation and autoimmunity. The disease is composed of an autoimmune component mediated by autoantibody immune complexes and B and T cell independent inflammation. The underlying mechanism is a gain-of-function mutation in Plcg2, which leads to hyperreactive external calcium entry in B cells and expansion of innate inflammatory cells. This mutant identifies Plcg2 as a key regulator in an autoimmune and inflammatory disease mediated by B cells and non-B, non-T haematopoietic cells and emphasizes that by distinct genetic modulation, a single point mutation can lead to a complex immunological phenotype.  相似文献   
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BACKGROUND: There is some community survey evidence for a cohort difference in female sexual orientation. OBJECTIVE: To determine whether there is a cohort difference in sexual orientation in Australia. METHODS: A community survey was carried out with a sample of 7,447 adults from the age groups 20-24, 40-44 and 60-64 years. As part of this survey respondents were asked a question on sexual orientation which was answered privately. RESULTS: A strong age cohort difference was found for women, with younger women more frequently reporting a homosexual or bisexual orientation. By contrast, no age cohort difference was found for men. CONCLUSION: These findings suggest that a heterosexual orientation may have become less common in younger cohorts of Australian women. This finding is consistent with data from other recent studies.  相似文献   
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Currently, no blood biomarker that specifically indicates injury to the proximal tubule of the kidney has been identified. Kidney injury molecule-1 (KIM-1) is highly upregulated in proximal tubular cells following kidney injury. The ectodomain of KIM-1 is shed into the lumen, and serves as a urinary biomarker of kidney injury. We report that shed KIM-1 also serves as a blood biomarker of kidney injury. Sensitive assays to measure plasma and serum KIM-1 in mice, rats, and humans were developed and validated in the current study. Plasma KIM-1 levels increased with increasing periods of ischemia (10, 20, or 30 minutes) in mice, as early as 3 hours after reperfusion; after unilateral ureteral obstruction (day 7) in mice; and after gentamicin treatment (50 or 200 mg/kg for 10 days) in rats. In humans, plasma KIM-1 levels were higher in patients with AKI than in healthy controls or post-cardiac surgery patients without AKI (area under the curve, 0.96). In patients undergoing cardiopulmonary bypass, plasma KIM-1 levels increased within 2 days after surgery only in patients who developed AKI (P<0.01). Blood KIM-1 levels were also elevated in patients with CKD of varous etiologies. In a cohort of patients with type 1 diabetes and proteinuria, serum KIM-1 level at baseline strongly predicted rate of eGFR loss and risk of ESRD during 5–15 years of follow-up, after adjustment for baseline urinary albumin-to-creatinine ratio, eGFR, and Hb1Ac. These results identify KIM-1 as a blood biomarker that specifically reflects acute and chronic kidney injury.  相似文献   
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BackgroundThe clinical course of COVID-19 includes multiple disease phases. Data describing post-hospital discharge outcomes may provide insight into disease course. Studies describing post-hospitalization outcomes of adults following COVID-19 infection are limited to electronic medical record review, which may underestimate the incidence of outcomes.ObjectiveTo determine 30-day post-hospitalization outcomes following COVID-19 infection.DesignRetrospective cohort studySettingQuaternary referral hospital and community hospital in New York City.ParticipantsCOVID-19 infected patients discharged alive from the emergency department (ED) or hospital between March 3 and May 15, 2020.MeasurementOutcomes included return to an ED, re-hospitalization, and mortality within 30 days of hospital discharge.ResultsThirty-day follow-up data were successfully collected on 94.6% of eligible patients. Among 1344 patients, 16.5% returned to an ED, 9.8% were re-hospitalized, and 2.4% died. Among patients who returned to the ED, 50.0% (108/216) went to a different hospital from the hospital of the index presentation, and 61.1% (132/216) of those who returned were re-hospitalized. In Cox models adjusted for variables selected using the lasso method, age (HR 1.01 per year [95% CI 1.00–1.02]), diabetes (1.54 [1.06–2.23]), and the need for inpatient dialysis (3.78 [2.23–6.43]) during the index presentation were independently associated with a higher re-hospitalization rate. Older age (HR 1.08 [1.05–1.11]) and Asian race (2.89 [1.27–6.61]) were significantly associated with mortality.ConclusionsAmong patients discharged alive following their index presentation for COVID-19, risk for returning to a hospital within 30 days of discharge was substantial. These patients merit close post-discharge follow-up to optimize outcomes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06924-0.KEY WORDS: COVID-19, mortality, re-admission, discharge  相似文献   
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