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ObjectivesThe detection of SARS-CoV-2 RNA in blood and platelet concentrates from asymptomatic donors, and the detection of viral particles on the surface and inside platelets during in vitro experiments, raised concerns over the potential risk for transfusion-transmitted-infection (TTI). The objective of this study was to assess the efficacy of the amotosalen/UVA pathogen reduction technology for SARS-CoV-2 in human platelet concentrates to mitigate such potential risk.Material and methodsFive apheresis platelet units in 100% plasma were spiked with a clinical SARS-CoV-2 isolate followed by treatment with amotosalen/UVA (INTERCEPT Blood System), pre- and posttreatment samples were collected as well as untreated positive and negative controls. The infectious viral titer was assessed by plaque assay and the genomic titer by quantitative RT-PCR. To exclude the presence of infectious particles post-pathogen reduction treatment below the limit of detection, three consecutive rounds of passaging on permissive cell lines were conducted.ResultsSARS-CoV-2 in platelet concentrates was inactivated with amotosalen/UVA below the limit of detection with a mean log reduction of > 3.31 ± 0.23. During three consecutive rounds of passaging, no viral replication was detected. Pathogen reduction treatment also inhibited nucleic acid detection with a log reduction of > 4.46 ± 0.51 PFU equivalents.ConclusionSARS-CoV-2 was efficiently inactivated in platelet concentrates by amotosalen/UVA treatment. These results are in line with previous inactivation data for SARS-CoV-2 in plasma as well as MERS-CoV and SARS-CoV-1 in platelets and plasma, demonstrating efficient inactivation of human coronaviruses.  相似文献   
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膝骨关节炎(Knee Osteoarthritis, KOA)属于临床难治性疾病,其高发病率、高致残性给国民健康、社会发展造成了沉重的负担。在这种不利局面下,中医药在KOA的临床防治上发挥了巨大的作用,其根据“辨证施治”理念的指导对患者采用个体化治疗往往能够取得良好的临床疗效 。然而中医学在传统认知上作为经验医学的集成,现有的KOA中医药基础研究结果尚未完全阐明其客观化、现代化的属性,阻碍了中医药防治KOA科学内涵的揭示以及全面、系统的临床研究的开展和新药研发,如何开展完善、合理、可行的基础研究以进行KOA中医药客观化和现代化探索成为研究者不得不解决的重大难题。随着系统生物学知识结构和研究手段的完善与更新,其与中医药的结合已经成为阐释并创新中医药理论内核、突破中医药研究瓶颈的重要方法。本文通过总结、分析目前KOA中医药基础研究的现状与不足,突出系统生物学在目前KOA中医药研究中的关键作用及应用趋势,以期为今后KOA的中医药研究和发展提供新的思路与对策。  相似文献   
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Preeclampsia is a disease with a significant incidence worldwide that is directly associated with 15% of maternal deaths. This is usually characterized by the presence of hypertension and proteinuria, which manifests itself from the middle of pregnancy. MicroRNAs are single-stranded RNA molecules that act primarily by degrading transcribed messenger RNA or inhibiting microRNA translation. Placental microRNAs play a role in the growth and function of the placenta, their potential use as diagnostic biomarkers is considered feasible due to the ability to enter the maternal circulation and be detectable in maternal plasma.  相似文献   
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《Cancer cell》2022,40(11):1294-1305.e4
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Optimizing the environment of complex bone healing and improving treatment of catastrophic bone fractures and segmental bone defects remains an unmet clinical need both human and equine veterinary medical orthopaedics. The objective of this study was to determine whether scAAV‐equine‐BMP‐2 transduced cells would induce osteogenesis in equine bone marrow derived mesenchymal stem cells (BMDMSCs) in vitro, and if these cells could be cryopreserved in an effort to osteogenically prime them as an “off‐the‐shelf” gene therapeutic approach for fracture repair. Our study found that transgene expression is altered by cell expansion, as would be expected by a transduction resulting in episomal transgene expression, and that osteoinductive levels could still be achieved 5 days after recovery, and protein expression would continue up to 14 days after transduction. This is the first evidence that cryopreservation of genetically modified BMDMSCs would not alter the osteoinductive potential or clinical use of allogeneic donor cells in cases of equine fracture repair. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1310–1317, 2019.  相似文献   
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Despite tremendous efforts to fight cancer, it remains a major public health problem and a leading cause of death worldwide. With increased knowledge of cancer pathways and improved technological platforms, precision therapeutics that specifically target aberrant cancer pathways have improved patient outcomes. Nevertheless, a primary cause of unsuccessful cancer therapy remains cancer drug resistance. In this review, we summarize the broad classes of resistance to cancer therapy, particularly pharmacokinetics, the tumor microenvironment, and drug resistance mechanisms. Furthermore, we describe how bacterial-mediated cancer therapy, a bygone mode of treatment, has been revitalized by synthetic biology and is uniquely suited to address the primary resistance mechanisms that confound traditional therapies. Through genetic engineering, we discuss how bacteria can be potent anticancer agents given their tumor targeting potential, anti-tumor activity, safety, and coordinated delivery of anti-cancer drugs.  相似文献   
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目的 分析重症监护病房(ICU)感染病原菌分布及其耐药趋势,为ICU有效预防与控制医院感染提供依据。方法 采用回顾性研究方法,收集我院2013-2017年综合ICU送检的25057份临床标本分离的病原菌进行细菌种类鉴定和药敏试验。结果 分离病原菌6938株,其中革兰阴性菌5513株(79.46%),革兰阳性菌710株(10.23%),真菌715株(10.31%),排名前4位分别为鲍曼不动杆菌(31.65%)、肺炎克雷伯菌(15.90%)、铜绿假单胞菌(11.46%)和大肠埃希菌(6.31%)。真菌随着时间变化呈现下降后升高趋势,鲍曼不动杆菌、铜绿假单胞菌和大肠埃希菌呈现升高后下降趋势,而肺炎克雷伯菌呈现下降后升高趋势。分离出多重耐药菌1387株,前3位分别为鲍曼不动杆菌(84.21%)、肺炎克雷伯菌(8.22%)和铜绿假单胞菌(4.83%)。5年间多重耐药鲍曼不动杆菌分布率均显著高于肺炎克雷伯菌和铜绿假单胞菌(P=0),且在2016年检出率达最高,2013和2017年检出率最低;多重耐药肺炎克雷伯菌在2017年检出率达最高,2013年检出率最低;多重耐药铜绿假单胞菌5年间差异无统计学意义(P>0.05)。结论 我院病原菌以革兰阴性菌为主,不同年份病原菌及其耐药性变化有所不同,应定期监测病原菌及其耐药性变迁,正确合理使用抗菌药物。  相似文献   
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