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1.
《The Journal of arthroplasty》2022,37(8):1636-1639
BackgroundThe use of personal-protection surgical helmet/hood systems is now a part of the standard surgical attire during arthroplasty in North America. There are no protocols for the disinfection of these helmets.MethodsThis is a prospective, single-center, observational study. Helmets worn by 44 members of the surgical team and foreheads of 44 corresponding surgical personnel were swabbed at three distinct time points. In addition, 16 helmets were treated with hypochlorite spray to determine if pathogens could be eliminated. Swabs obtained were processed for culture and next-generation sequencing (NGS).ResultsOf the 132 helmet samples, 97 (73%) yielded bacteria on culture and 94 (71%) had evidence of bacterial–deoxyribonucleic acid (DNA) on NGS. Of the swabs sent for bacterial identification at the three time points, at least one from each helmet was positive for a pathogen(s). Of the 132 forehead samples, 124 (93%) yielded bacteria on culture and 103 (78%) had evidence of bacterial-DNA on NGS. The most commonly identified organism from helmets was Cutibacterium acnes (86/132) on NGS and Staphylococcus epidermidis (47/132) on culture. The most commonly identified organism from the foreheads of surgical personnel was Cutibacterium acnes (100/132) on NGS and Staphylococcus epidermidis (70/132) on culture. Sanitization of helmets was totally effective; no swabs taken the following morning for culture and NGS identified any bacteria.ConclusionThis study demonstrates that surgical helmets worn during orthopedic procedures are contaminated with common pathogens that can potentially cause surgical site infections. The findings of this study should at the minimum compel us to develop protocols for the disinfection of these helmets.  相似文献   
2.
Lifetime red cell concentrate (RCC) transfusions still account for significant iron overload‐related morbidity and mortality despite chelation therapy in thalassaemia. The cumulative risk of transfusion‐transmitted infections is substantial for thalassaemia patients. Pathogen reduction technologies for RCC may imply a proactive approach against new/re‐emerging pathogens and may be an ultimate safeguard for transfusion safety in the developing countries. Red cell alloimmunization may become a significant clinical challenge in thalassaemia. The availability of high‐throughput molecular blood group antigen typing in the donors may allow perfect match transfusion, beyond ABO‐D and CEK antigen‐matched transfusions. Allogeneic stem cell transplantation (A‐SCT) is the only available curative therapy in thalassaemia, but carries a substantial risk of serious adverse events and mortality. Gene addition therapy for correction of the α‐globin chain imbalance overcomes the problems of donor availability and immunological complications of A‐SCT. Gene editing by either gene disruption or correction emerged as a potential alternative to gene addition therapy in beta‐thalassaemia. A new era of novel therapeutics targeting α/β imbalance, ineffective erythropoiesis or iron dysregulation is unfolding in thalassaemia management, and a number of those now have agents in preclinical and clinical development. Hydroxyurea (HU) may improve globin chain imbalance and be beneficial for reducing or omitting transfusion requirement. Ruxolitinib has allowed steady decrease in spleen volume that may serve for avoiding splenectomy in beta‐thalassaemia. Luspatercept may restore normal erythroid differentiation and improve anaemia. Hepcidin mimetics or TMPRSS6 inhibitors may modulate ineffective erythropoiesis by iron restriction and improve anaemia and organ iron loading.  相似文献   
3.
Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security.  相似文献   
4.
徐慧  陈敏  孙永峰  程星  王琦  靳蓉 《广东医学》2020,41(23):2394-2397
目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液(BALF)病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料,将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果(1)989例重症社区获得性肺炎患儿病原检出阳性716例,阳性率72.40%,细菌、病毒、支原体检出率分别33.27% (329例)、22.45%(222例)、31.45%(311例)。(2)细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+);而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性,对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性,对亚胺培南、万古霉素、利奈唑烷均无耐药发生。(3)病毒感染检出222例,其中呼吸道合胞病毒131例,腺病毒检测49例,流感病毒6例(A型2例,B型4例),副流感病毒36例(1型3例、2型4例、3型29例),病毒检出率以0~12月龄组最高,RSV、ADV感染主要集中在冬春季节。(4)肺炎支原体检出阳性率31.45%(311例),肺炎支原体检出率以3~5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主,1~12月龄组的病毒感染检出率比较高。  相似文献   
5.
目的了解临床标本中主要致病菌分布及敏感性分析,指导抗生素的选择及合理治疗方法对我院1994~1996年临床分离的1870株细菌的分布及敏感性、耐药性进行分析,1996年与1994年的结果进行比较,并将1995年的结果与北京地区5家教学医院同年的结果进行比较。结果分离菌株主要分布于呼吸道、消化道、泌尿道、血液及骨髓。G+菌占10.5%,G-菌占89.5%,占明显优势。沙门氏菌对头孢唑啉和哌拉西林的耐药性明显降低(P<0.01),大肠埃希氏菌对氨苄西林和氟嗪酸的耐药性明显增高(P<0.01),其余菌株无明显差异。抗生素敏感性覆盖率最高的是复达欣,其次为丁胺卡那,最低者氨苄西林。大肠埃希氏菌、假单胞菌对哌拉西林的耐药率,克雷伯杆菌属对西力欣的耐药率,肠肝菌属对哌拉西林的耐药率均高于北京地区。结论本组资料显示不断监测和分析菌丛的变化及对不同抗生素耐药性出现的频率和耐药谱至关重要。  相似文献   
6.
肺螨类生境研究   总被引:24,自引:0,他引:24  
本文叙述了肺螨类的孳生环境及其不同生境里肺螨的种群分布,并对分离出的28种螨的生境和肺螨病患者的工作环境进行了对比分析,认为螨在肺螨病患者工作环境中的分布和肺螨的生境基本上相符合,因此证实了患者的病原体是直接来源于工作环境。  相似文献   
7.
病原生物学多媒体网络互动教学实验室的建设与展望   总被引:5,自引:0,他引:5  
介绍了病原生物学多媒体网络互动教学实验室的建设和应具备的功能 ,论述了多媒体互动网络的建成对病原生物学实验教学环境和实验教学效果的积极促进作用 ,并对实验室以后的发展方向进行了展望  相似文献   
8.
解毒降浊、益气活瘀是治疗老年缺血性卒中的主要治则   总被引:2,自引:0,他引:2  
老年缺血性卒中在病因病机、治疗方法等方面迥异于老年前期缺血性卒中患者。根据老年人的生理病理特点结合临床实际,认为正虚血瘀为本,浊毒内蕴为标,毒损脑络为老年脑缺血损伤的终结;正虚血瘀、浊毒内蕴是老年脑缺血损伤的根本原因;解毒降浊、益气活血是治疗老年缺血性卒中的重要方法之一。  相似文献   
9.
The aim of the study was to examine whether proteolytic artifacts, which result in a loss and poor resolution of protein bands, occur during sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis analysis of cellular proteins from selected proteolytic ( Porphyromonas gingivalis, Prevotella nigrescens and Treponema denticola ) and non-proteolytic ( Fusobacterium nudeatum ) bacteria. Conditions to limit or prevent proteolysis were also investigated. Bacterial cells were incubated in solubilizing buffer (SDS +β mercaptoethanol) at room temperature for various periods of time before boiling. A control assay consisted of trichloroacetic acid-treated bacterial cells. Cellular proteins were separated by electrophoresis and stained with Coomassie blue. Proteolysis occurred very rapidly in the case of P. gingivalis (<30 s), whereas a longer incubation time (>1 h) was required to observe similar effects in P. nigrescens and T. denticola. No proteolysis was observed for F. nudeatum. In all cases, heat (100°C) and low pH (<4) treatments of bacterial cells could avoid production of proteolytic artifacts. Incorporation of specific protease inhibitors before solubilization of bacteria could also prevent proteolysis. More particularly, N -α- p -tosyl- l -lysine chloromethyl ketone (TLCK), iodoacetamide and diisopropylfluorophosphate (50 mM) were highly efficient for P. gingivalis, P. nigrescens and T. denticola , respectively. When outer membranes of P. gingivalis were prepared in the presence of TLCK, numerous additional protein bands, not seen in the absence of TLCK, were detected. The present study suggests that specific protease inhibitors, effective in preventing proteolysis. should be identified and added during cell fractionation and protein purification procedures.  相似文献   
10.
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