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Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.  相似文献   
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IntroductionMonoclonal antibody therapy has been reported to be highly effective for preventing hospitalisation and severe cases in patients with Coronavirus Disease 2019 (COVID-19). However, since the drug is not readily available, it is important to rapidly and appropriately identify high-risk patients who can benefit most from therapy. Therefore, we designed a risk scoring system to identify at-risk COVID-19 patients in our region during the largest surge of COVID-19, from July to September 2021.MethodsAccording to the risk scores, confirmed COVID-19 patients were introduced to receive REGN-CoV-2 to our hospital by regional health centre from 18th August (Term 3). The primary outcome was the comparison of the number of hospitalisation and severe condition with other periods, the 4th wave (Term 1) and the early part of the 5th wave (Term 2) in Japan.ResultsDuring Term 3, 115 patients were stratified with the scoring system and administered REGN-COV-2. The number of hospitalisation vs severe cases were 60 (5.2%) vs 14 (1.2%), 8 (1.5%) vs 3 (0.6%) and 21 (1.2%) vs 2 (0.1%), in term 1, 2 and 3, respectively. Among those aged <60 years, compared with term 1, the relative risk of hospitalisation and severe condition were 0.25 (95% CI: 0.12–0.53) and 0.10 (95% CI: 0.01–0.80), respectively, in term 3. Drug adverse events were fever (3: 2.6%), headache (1: 0.9%) and neck rash (1: 0.9%), all events were resolved within 24 h wth no serious adverse event.ConclusionsThe administration of monoclonal antibody therapy using a risk scoring system significantly reduced the number of hospitalisation and disease severity of COVID-19 without any serious adverse events and avoided regional medical collapse.  相似文献   
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目的了解某社区第二类疫苗接种及疑似预防接种异常反应(AEFI)情况。方法通过查询疫苗出入库系统和中国免疫规划信息管理系统,对2019年该社区第二类疫苗使用及AEFI报告情况进行分析。结果2019年,该社区接种门诊共接种第二类疫苗21种7449剂,接种数最多的是13价肺炎疫苗(784剂)。接种数居前6位的依次为13价肺炎疫苗、ACYW135群流脑多糖疫苗、轮状病毒疫苗、百白破-IPV-HIB五联疫苗、手足口EV71疫苗、九价人乳头瘤疫苗。累计报告AEFI病例94例,发生率为1.26%;一般反应占96.81%,异常反应占3.19%。报告AEFI疫苗共12种,报告发生率居前6位的分别为13价肺炎疫苗、百白破-IPV-HIB五联疫苗、百白破-IPV-HIB四联疫苗、手足口EV71疫苗、九价HPV疫苗、AC结合流脑疫苗。结论第二类疫苗品种接种量均有所增加,AEFI报告发生率有所波动,需加强监测。  相似文献   
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PurposeTo examine the long-term clinical outcomes of patients with anti-centromere antibody (ACA)-positive critical limb-threatening ischemia (CLTI) who were treated with endovascular therapy (EVT).Materials and MethodsThis was a retrospective analysis using a database of 423 consecutive CLTI patients (543 limbs, Rutherford class 4–6) who underwent EVT between January 2011 and March 2013. The patients were divided into 2 groups: an ACA-positive group (10 limbs, 8 patients) and a control group (46 limbs, 43 patients). The control group was defined as female, non-dialysis, and those who were able to obtain a below-knee angiogram.ResultsNone of the 8 ACA-positive CLTI patients had previously been diagnosed as ACA positive. No significant difference was observed in the below-the-knee lesion distribution and severity between the ACA-positive group and the control group. The median observational period was 51 months. The survival rate was 54% in the ACA-positive group and 76% in the control group at 5 years after EVT (P = .732). The freedom from major amputation rate was 60% in the ACA-positive group and 91% in the control group at 5 years after EVT (P = .029). The technical EVT success rate in the ACA-positive group was 70% (7/10). Of the successful EVT cases, 71% (5/7) of patients achieved complete wound healing or rest pain relief; however, 60% (3/5) had a recurrence of wounds.ConclusionsIn a series of ACA-positive patients with CLTI, successful EVT had acceptable outcomes with respect to wound healing with short-term results. However, the major amputation rate for ACA-positive patients was high in long-term follow-up.  相似文献   
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Plasma provided by COVID-19 convalescent patients may provide therapeutic relief as the number of COVID-19 cases escalates steeply worldwide. Prior findings in various viral respiratory diseases including SARS-CoV-related pneumonia suggest that convalescent plasma can reduce mortality, although formal proof of efficacy is still lacking. By reducing viral spread early on, such an approach may possibly downplay subsequent immunopathology. Identifying, collecting, qualifying and preparing plasma from convalescent patients with adequate SARS-CoV-2-neutralizing Ab titres in an acute crisis setting may be challenging, although well within the remit of most blood establishments. Careful clinical evaluation should allow to quickly establish whether such passive immunotherapy, administered at early phases of the disease in patients at high risk of deleterious evolution, may reduce the frequency of patient deterioration, and thereby COVID-19 mortality.  相似文献   
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《Vaccine》2020,38(50):7916-7927
Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory illness in children of less than 5 years of age which usually results in hospitalization or even in death. Vaccine development is hampered in consequence of a failed vaccine trial with fatalities in the 1960s. Even though research has been more focused on the RSV fusion protein in its pre-fusion conformation, maternal vaccination with post-fusion protein (post F) was considered as a promising vaccine strategy for passive immunization of babies, because post F preserves very potent neutralizing epitopes. We extensively analyzed post F-binding B cell receptor (BCR) repertoires of three vaccinees who received a post F-subunit vaccine in the context of a first-in-human, Phase 1, randomized, observer-blind, placebo-controlled clinical trial (ClinicalTrials.gov Identifier: NCT02298179). In order to compare the vaccine-induced BCR repertoires with BCR repertoires induced by natural infection, we also analyzed pre F- and post F-binding BCRs isolated from a healthy blood donor with relatively high F-binding memory B cell (MBC) frequencies. Analysis of the vaccine-induced repertoires revealed that preferentially VH4-encoded BCRs were expanded in response to vaccination. Estimation of antigen-driven selection further demonstrated that expanded BCRs accumulated positively selected replacement mutations which substantiated the hypothesis that post F-vaccination induces diversification of VH4-encoded BCRs in germinal centers. Comparison of the vaccine-induced BCR repertoires with clonally related pre and post F-binding BCRs of the healthy blood donor suggested that the vaccine expanded pre/post F cross-reactive MBCs. Interestingly, several vaccine-induced BCRs shared stereotypic VDJ gene junctions with known neutralizing Abs. Once expressed for functional characterization, the selected monoclonal Abs demonstrated the predicted neutralization activities in plaque reduction neutralization assays indicating that the post F-vaccine induced expansion of neutralizing BCRs.  相似文献   
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