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1.
Galactosyl transferase knock-out pig lungs fail rapidly in baboons. Based on previously identified lung xenograft injury mechanisms, additional expression of human complement and coagulation pathway regulatory proteins, anti-inflammatory enzymes and self-recognition receptors, and knock-down of the β4Gal xenoantigen were tested in various combinations. Transient life-supporting GalTKO.hCD46 lung function was consistently observed in association with either hEPCR (n = 15), hTBM (n = 4), or hEPCR.hTFPI (n = 11), but the loss of vascular barrier function in the xenograft and systemic inflammation in the recipient typically occurred within 24 h. Co-expression of hEPCR and hTBM (n = 11) and additionally blocking multiple pro-inflammatory innate and adaptive immune mechanisms was more consistently associated with survival >1 day, with one recipient surviving for 31 days. Combining targeted genetic modifications to the lung xenograft with selective innate and adaptive immune suppression enables prolonged initial life-supporting lung function and extends lung xenograft recipient survival, and illustrates residual barriers and candidate treatment strategies that may enable the clinical application of other organ xenografts.  相似文献   
2.
《Clinical microbiology and infection》2022,28(9):1286.e1-1286.e8
ObjectiveAntibiotic susceptibility testing (AST) is necessary in order to adjust empirical antibiotic treatment, but the interpretation of results requires experience and knowledge. We have developed a machine learning software that is capable of reading AST images without any human intervention and that automatically interprets the AST, based on a database of antibiograms that have been clinically validated with European Committee on Antimicrobial Susceptibility Testing rules.MethodsWe built a database of antibiograms that were labelled by senior microbiologists for three species: Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. We then developed Antilogic, a Python software based on an original image segmentation module and supervised learning models that we trained against the database. Finally, we blind tested Antilogic against a validation set of 5100 photos of antibiograms.ResultsWe trained Antilogic against a database of 18072 pictures of antibiograms. Overall agreement against the validation set reached 97% (16 855/17 281) regarding phenotypes. The severity rate of errors was also evaluated: 1.66% (287/17 281) were major errors and 0.80% (136/17 281) were very major errors. After implementation of uncertainty quantifications, the rate of errors decreased to 0.80% (114/13 451) and 0.42% (51/13 451) for major and very major errors respectively.DiscussionAntilogic is the first machine learning software that has been developed for AST interpretation. It is based on a novel approach that differs from the typical diameter measurement and expert system approach. Antilogic is a proof of concept that artificial intelligence can contribute to faster and easier diagnostic methods in the field of clinical microbiology.  相似文献   
3.
医学高等院校实验室是培养医学生创新能力的主要场所,其建设和管理水平是高校科研实力、学科建设实力和人才培养能力的综合体现。将精细化管理模式引用到医学实验室安全管理中,为学生提供一个安全保障的实验环境,才能更有利于实验的顺利开展和高校对人才的培养。本文主要对医学实验室安全管理存在的主要问题进行剖析,并基于精细化管理模式下通过对强化安全教育管理、保障人员配备、引进现代化管理办法等方面创新实验室安全管理进行阐述,为医学高等院校实验室现代化建设提供基本保障。  相似文献   
4.
PurposeTo evaluate temporal trends, practice variation, and associated outcomes with the use of intravascular ultrasound (US) during deep venous stent placement among Medicare beneficiaries.Materials and MethodsAll lower extremity deep venous stent placement procedures performed between January 1, 2017, and December 31, 2019 among Medicare beneficiaries were included. Temporal trends in intravascular US use were stratified by procedural setting and physician specialty. The primary outcome was a composite of 12-month all-cause mortality, all-cause hospitalization, or repeat target vessel intervention. The secondary outcome was a composite of 12-month stent thrombosis, embolization, or restenosis.ResultsAmong the 20,984 deep venous interventions performed during the study period, 15,184 (72.4%) utilized intravascular US. Moderate growth in intravascular US use was observed during the study period in all clinical settings. There was a variation in the use of intravascular US among all operators (median, 77.3% of cases; interquartile range, 20.0%–99.2%). In weighted analyses, intravascular US use during deep venous stent placement was associated with a lower risk of both the primary (adjusted hazard ratio, 0.72; 95% confidence interval [CI], 0.69–0.76; P < .001) and secondary (adjusted hazard ratio, 0.32; 95% CI, 0.27–0.39; P < .001) composite end points.ConclusionsIntravascular US is frequently used during deep venous stent placement among Medicare beneficiaries, with further increase in use from 2017 to 2019. The utilization of intravascular US as part of a procedural strategy was associated with a lower cumulative incidence of adverse outcomes after the procedure, including venous stent thrombosis and embolization.  相似文献   
5.
BackgroundRhythmic joint mobilizations (RJM) of the temporomandibular joint (TMJ) are employed to relieve pain and improve function in patients with temporomandibular disorders (TMD). However, the evidence on the immediate effects of RJM in patients with TMD is scarce. The aim of this study was to assess the immediate clinical and functional effects of RJM in patients with TMD.Materials and methodsThis was a one-group quasi-experimental before and after study. Thirty-eight patients with TMD were assessed by means of pain intensity (visual analogue score, VAS), pressure pain threshold (PPT, measured through pressure algometry on the masseter and temporal muscles), mouth opening (MO, measured with a ruler), and surface electromyographic activity of the masseter and temporal muscles (asymmetry index, AI). Measurements were performed before and after a single, 1-min session of RJM of each TMJ. All statistical analyses were performed using the SPSS version 20.0 statistical package.ResultsA statistical significant difference was found in pain intensity, PPT and MO after the intervention (p < 0.05). No difference was found in the AI. A large effect size was observed for pain intensity, PPT of the left and right masseter muscles and MO (d = 0.85–1.13), whereas for the left and right temporal muscles the effect size was moderate (d = 0.62) and small, respectively (d = 0.49).ConclusionIn this sample of patients with TMD, a single session of RJM of the TMJ seemed to be effective in reducing pain intensity, increasing PPT and improving MO immediately after the intervention, without differences in the AI.  相似文献   
6.
There are many preanalytical variables (PAV) that are known to affect coagulation testing. The more commonly acknowledged PAV addressed by the clinical laboratory tend to start with their influence on blood collection, but realistically coagulation PAV starts with the patient, where the laboratory has less influence or control. Patient selection and appropriate timing for blood collection may be integral for assuring proper diagnosis and management. Laboratory control and assurance for ideal phlebotomy practice would mitigate most PAVs related to blood collection to minimize suboptimal sample collection. Laboratory oversight of sample transportation, processing and storage will assure sample integrity until testing can be facilitated. The purpose of this document is to review common PAV that should be taken into consideration when ordering, performing and interpreting a coagulation test result, with additional attention to the effect of direct oral anticoagulants (DOACs).  相似文献   
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8.
目的 分析马尔尼菲篮状菌(TM)感染性淋巴结炎的临床病理特点。方法 回顾性分析15例TM感染性淋巴结炎的临床资料、病理形态特点、病原体检查、治疗情况等。结果 15例TM感染性淋巴结炎中,男14例,女1例,年龄26~67岁,平均(49.1±11.87)岁,包括13例艾滋病和2例糖尿病患者,伴有颈部、锁骨上、腋窝、腹股沟等部位浅表淋巴结肿大。粗针穿刺的条索状淋巴结组织,其结构全部或部分被炎性病变所取代,8例显微镜下形态以吞噬病原体的组织细胞弥漫性浸润为主;5例以广泛凝固性坏死为主伴散在少量病原体及核碎屑;2例以成纤维细胞小结节状增生,形成肉芽肿结构的改变为主,多核巨细胞少、散在分布。病原体大小、形态较一致,呈圆形、椭圆形或腊肠状,团聚成簇,如桑葚样,淀粉酶消化后过碘酸希夫及六胺银染色可见包含横隔的菌体结构。15例患者血液、肺泡灌洗液、痰液或者淋巴结抽出液真菌培养均查见TM生长。临床及时抗真菌治疗,15例患者病情好转后出院。结论 TM感染性淋巴结炎往往是全身侵袭性TM病晚期阶段的突出表现之一,容易被临床误诊,通过淋巴结粗针穿刺活检及早明确诊断,以免延误治疗,从而提高治愈率。  相似文献   
9.
陈平  陈婷婷 《检验医学》2022,37(1):83-86
目的依据ISO 15189质量体系建立覆盖检验全流程的智能结构化检验知识库,满足各个医疗环节对检验知识库的需求。方法在ISO 15189质量体系下,引入检验认知计算理论,通过信息化方法实现对检验知识源的提取、挖掘,自定义知识节点,并持续对数据库信息进行更新。结果建立的智能结构化检验知识库可以从检验各业务节点采集知识,通过富文本编辑,自动生成服务手册、项目书册、项目操作规程、仪器操作规程、采集手册,再将形成的程序化文件各节点碎片化分布在实验室信息系统(LIS)中,支持工作站、移动终端对检验知识库的浏览、查阅和数据分享。结论通过建立结构化的检验知识库,将检验相关的基础信息进行分类编排,使信息和知识有序化,缩短了搜索时间,加快了知识和信息的流动,有利于检验知识的共享与交流。  相似文献   
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