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41.
42.
Edward R. Cachay Amy Sitapati Joseph Caperna Kellie Freeborn Joseph T. Lonergan Edward Jocson William C. Mathews for the Owen Clinic Study Group 《PloS one》2009,4(12)
Background
The Centers for Disease Control recommend screening for asymptomatic sexually transmitted infection (STI) among HIV-infected men when there is self-report of unprotected anal-receptive exposure. The study goals were: (1) to estimate the validity and usefulness for screening policies of self-reported unprotected anal-receptive exposure as a risk indicator for asymptomatic anorectal infection with Neisseria gonorrhoeae (GC) and/or Chlamydia trachomatis (CT). (2) to estimate the number of infections that would be missed if anal diagnostic assays were not performed among patients who denied unprotected anorectal exposure in the preceding month.Methods and Findings
Retrospective analysis in HIV primary care and high resolution anoscopy (HRA) clinics. HIV-infected adult men were screened for self-reported exposure during the previous month at all primary care and HRA appointments. Four sub-cohorts were defined based on microbiology methodology (GC culture and CT direct fluorescent antibody vs. GC/CT nucleic acid amplification test) and clinical setting (primary care vs. HRA). Screening question operating characteristics were estimated using contingency table methods and then pooled across subcohorts. Among 803 patients, the prevalence of anorectal GC/CT varied from 3.5–20.1% in the 4 sub-cohorts. The sensitivity of the screening question for self-reported exposure to predict anorectal STI was higher in the primary care than in the HRA clinic, 86–100% vs. 12–35%, respectively. The negative predictive value of the screening question to predict asymptomatic anorectal STI was ≥90% in all sub-cohorts. In sensitivity analyses, the probability of being an unidentified case among those denying exposure increased from 0.4–8.1% in the primary care setting, and from 0.9–18.8% in the HRA setting as the prevalence varied from 1–20%.Conclusion
As STI prevalence increases, denial of unprotected anal-receptive exposure leads to an increasingly unacceptable proportion of unidentified asymptomatic anorectal STI if used as a criterion not to obtain microbiologic assays. 相似文献43.
Strom A Kolb H Martin S Herder C Simon MC Koenig W Heise T Heinemann L Roden M Schloot NC;DIATOR Study Group 《PloS one》2012,7(3):e33108
Background
A recent randomized placebo-controlled trial of the effect of atorvastatin treatment on the progression of newly diagnosed type 1 diabetes suggested a slower decline of residual beta cell function with statin treatment. Aim of this secondary analysis was to identify patient subgroups which differ in the decline of beta cell function during treatment with atorvastatin.Methodology/Principal Findings
The randomized placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and detectable islet autoantibodies (mean age 30 years, 40% females), in 12 centers in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. For this secondary analysis patients were stratified by single baseline characteristics which were considered to possibly be modified by atorvastatin treatment. Subgroups defined by age, sex or by baseline metabolic parameters like body mass index (BMI), total serum cholesterol or fasting C-peptide did not differ in C-peptide outcome after atorvastatin treatment. However, the subgroup defined by high (above median) baseline C-reactive protein (CRP) concentrations exhibited higher stimulated C-peptide secretion after statin treatment (p = 0.044). Individual baseline CRP levels correlated with C-peptide outcome in the statin group (r2 = 0.3079, p<0.004). The subgroup with baseline CRP concentrations above median differed from the corresponding subgroup with lower CRP levels by higher median values of BMI, IL-6, IL-1RA, sICAM-1 and E-selectin.Conclusions/Significance
Atorvastatin treatment may be effective in slowing the decline of beta cell function in a patient subgroup defined by above median levels of CRP and other inflammation associated immune mediators.Trial Registration
ClinicalTrials.gov NCT00974740相似文献44.
Michael G. Hanna IV Ioanna Mela Lei Wang Robert M. Henderson Edwin R. Chapman J. Michael Edwardson Anjon Audhya 《The Journal of biological chemistry》2016,291(3):1014-1027
The majority of biosynthetic secretory proteins initiate their journey through the endomembrane system from specific subdomains of the endoplasmic reticulum. At these locations, coated transport carriers are generated, with the Sar1 GTPase playing a critical role in membrane bending, recruitment of coat components, and nascent vesicle formation. How these events are appropriately coordinated remains poorly understood. Here, we demonstrate that Sar1 acts as the curvature-sensing component of the COPII coat complex and highlight the ability of Sar1 to bind more avidly to membranes of high curvature. Additionally, using an atomic force microscopy-based approach, we further show that the intrinsic GTPase activity of Sar1 is necessary for remodeling lipid bilayers. Consistent with this idea, Sar1-mediated membrane remodeling is dramatically accelerated in the presence of its guanine nucleotide-activating protein (GAP), Sec23-Sec24, and blocked upon addition of guanosine-5′-[(β,γ)-imido]triphosphate, a poorly hydrolysable analog of GTP. Our results also indicate that Sar1 GTPase activity is stimulated by membranes that exhibit elevated curvature, potentially enabling Sar1 membrane scission activity to be spatially restricted to highly bent membranes that are characteristic of a bud neck. Taken together, our data support a stepwise model in which the amino-terminal amphipathic helix of GTP-bound Sar1 stably penetrates the endoplasmic reticulum membrane, promoting local membrane deformation. As membrane bending increases, Sar1 membrane binding is elevated, ultimately culminating in GTP hydrolysis, which may destabilize the bilayer sufficiently to facilitate membrane fission. 相似文献
45.
This study explored consumer liking and perception of pork patties with an added functional health ingredient: shiitake (Lentinus edodes P.) mushroom powder. In addition, patties with and without sodium tripolyphosphate were tested. Both native Korean and U.S. consumers evaluated the products. Pork patties made with both phosphate and mushroom powder were found to be acceptable by Korean consumers, but increases in mushroom powder in patties with phosphate decreased acceptability for U.S. consumers. However, addition of mushroom powder to patties without phosphate increased acceptability for U.S. consumers, perhaps because it tended to increase texture acceptance and juiciness. Thus, addition of mushroom powder as a functional ingredient in pork patties, while possible, would require different formula modifications to appeal to consumers of differing nationalities. 相似文献
46.
A. Justin Nowakowski James I. Watling Michelle E. Thompson George A. Brusch IV Alessandro Catenazzi Steven M. Whitfield David J. Kurz Ángela Suárez‐Mayorga Andrés Aponte‐Gutiérrez Maureen A. Donnelly Brian D. Todd 《Ecology letters》2018,21(3):345-355
Human activities often replace native forests with warmer, modified habitats that represent novel thermal environments for biodiversity. Reducing biodiversity loss hinges upon identifying which species are most sensitive to the environmental conditions that result from habitat modification. Drawing on case studies and a meta‐analysis, we examined whether observed and modelled thermal traits, including heat tolerances, variation in body temperatures, and evaporative water loss, explained variation in sensitivity of ectotherms to habitat modification. Low heat tolerances of lizards and amphibians and high evaporative water loss of amphibians were associated with increased sensitivity to habitat modification, often explaining more variation than non‐thermal traits. Heat tolerances alone explained 24–66% (mean = 38%) of the variation in species responses, and these trends were largely consistent across geographic locations and spatial scales. As habitat modification alters local microclimates, the thermal biology of species will likely play a key role in the reassembly of terrestrial communities. 相似文献
47.
Epidemiology and Outcome of Severe Sepsis and Septic Shock in Intensive Care Units in Mainland China
Jianfang Zhou Chuanyun Qian Mingyan Zhao Xiangyou Yu Yan Kang Xiaochun Ma Yuhang Ai Yuan Xu Dexin Liu Youzhong An Dawei Wu Renhua Sun Shusheng Li Zhenjie Hu Xiangyuan Cao Fachun Zhou Li Jiang Jiandong Lin Enqiang Mao Tiehe Qin Zhenyang He Lihua Zhou Bin Du for the China Critical Care Clinical Trials Group 《PloS one》2014,9(9)
Introduction
Information about sepsis in mainland China remains scarce and incomplete. The purpose of this study was to describe the epidemiology and outcome of severe sepsis and septic shock in mixed ICU in mainland China, as well as the independent predictors of mortality.Methods
We performed a 2-month prospective, observational cohort study in 22 closed multi-disciplinary intensive care units (ICUs). All admissions into those ICUs during the study period were screened and patients with severe sepsis or septic shock were included.Results
A total of 484 patients, 37.3 per 100 ICU admissions were diagnosed with severe sepsis (n = 365) or septic shock (n = 119) according to clinical criteria and included into this study. The most frequent sites of infection were the lung and abdomen. The overall ICU and hospital mortality rates were 28.7% (n = 139) and 33.5% (n = 162), respectively. In multivariate analyses, APACHE II score (odds ratio[OR], 1.068; 95% confidential interval[CI], 1.027–1.109), presence of ARDS (OR, 2.676; 95%CI, 1.691–4.235), bloodstream infection (OR, 2.520; 95%CI, 1.142–5.564) and comorbidity of cancer (OR, 2.246; 95%CI, 1.141–4.420) were significantly associated with mortality.Conclusions
Our results indicated that severe sepsis and septic shock were common complications in ICU patients and with high mortality in China, and can be of help to know more about severe sepsis and septic shock in China and to improve characterization and risk stratification in these patients. 相似文献48.
Barnett YA Eger K Eriksson S Folkers G Hansen PE Hofbauer R Komitowsky D Milon A Munch-Petersen B;European Thymidine Kinase Study Group 《Biotechnology advances》1994,12(4):663-668
A precondition for the chemotherapeutic treatment of a variety of virally-induced human diseases and malignant conditions is a highly selective interaction of the drug molecule to be used with it's biological target. To ensure the development of novel, effective drugs, it is essential that the biological target is well characterised with regard to it's structure and activity. Such characterisation relies upon adequate amounts of pure target being available. One of the most important enzymatic importers for antimetabolites is the enzyme thymidine kinase. In this article an in vitro protein expression system is described which facilitates the production of milligram amounts of pure and biologically active thymidine kinase, from a number of important biological sources. Results have shown that the in vitro produced enzyme has the exact biochemical propeties of the in vivo enzyme. Thus the in vitro protein expression system is an ideal vechicle to facilitate an in depth investigation of the enzyme's biological properties. 相似文献
49.
Umberto Raucci Rossella Rossi Roberto Da Cas Concita Rafaniello Nadia Mores Giulia Bersani Antonino Reale Nicola Pirozzi Francesca Menniti-Ippolito Giuseppe Traversa Italian Multicenter Study Group for Vaccine Safety in Drug Children 《PloS one》2013,8(7)
Objective
Stevens-Johnson Syndrome (SJS) is one of the most severe muco-cutaneous diseases and its occurrence is often attributed to drug use. The aim of the present study is to quantify the risk of SJS in association with drug and vaccine use in children.Methods
A multicenter surveillance of children hospitalized through the emergency departments for acute conditions of interest is currently ongoing in Italy. Cases with a diagnosis of SJS were retrieved from all admissions. Parents were interviewed on child’s use of drugs and vaccines preceding the onset of symptoms that led to the hospitalization. We compared the use of drugs and vaccines in cases with the corresponding use in a control group of children hospitalized for acute neurological conditions.Results
Twenty-nine children with a diagnosis of SJS and 1,362 with neurological disorders were hospitalized between 1st November 1999 and 31st October 2012. Cases were more frequently exposed to drugs (79% vs 58% in the control group; adjusted OR 2.4; 95% CI 1.0–6.1). Anticonvulsants presented the highest adjusted OR: 26.8 (95% CI 8.4–86.0). Significantly elevated risks were also estimated for antibiotics use (adjusted OR 3.3; 95% CI 1.5–7.2), corticosteroids (adjusted OR 4.2; 95% CI 1.8–9.9) and paracetamol (adjusted OR 3.2; 95% CI 1.5–6.9). No increased risk was estimated for vaccines (adjusted OR: 0.9; 95% CI 0.3–2.8).Discussion
Our study provides additional evidence on the etiologic role of drugs and vaccines in the occurrence of SJS in children. 相似文献50.
Sauropod Trackway Reflecting an Unusual Walking Pattern from the Early Cretaceous of Shandong Province,China 总被引:1,自引:0,他引:1
Lida Xing Yongqing Liu Daniel Marty Hongwei Kuang Hendrik Klein W. Scott Persons IV 《Ichnos》2017,24(1):27-36
The trackway of a quadrupedal dinosaur from the Early Cretaceous (Albian) Qingquan tracksite (Tancheng, Shandong Province) is redescribed, and the trackmaker is identified as a sauropod. The trackway makes a slight turn towards the northwest and is characterized by an extremely narrow gauge pattern and an unusual configuration, i.e., a conspicuous difference between the position of the left and right manus tracks with respect to the position of the preceding pes track. Left manus tracks are located on the inside of the trackway, very close (and sometimes even in connection) to the opposite right pes tracks. So far, the Qingquan trackway is possibly the only extremely narrow-gauge sauropod trackway known from China. However, it is not clear to what extent this extremely narrow gauge pattern is related to the turning or a special behavior, or even linked to an injury (“limping trackway”). We tentatively attribute the Qingquan trackway to cf. Parabrontopodus, even though it has a rather low heteropody that is significantly lower than in Parabrontopodus and not typical for narrow-gauge sauropod trackways, but occurs in the wide-gauge ichnotaxon Brontopodus. Because of this discrepancy, the Qingquan trackway cannot readily be attributed to a more basal sauropod, which is generally considered the producer of narrow-gauge trackways. Therefore, the identification of a distinct sauropod group is not possible presently. The only skeletal remains of sauropods from the Lower Cretaceous of Shandong Province belong to the large titanosauriform, Euhelopus zdanskyi. 相似文献