miRNA在脓毒症病原微生物诊断中的研究进展

脓毒症是由感染引起宿主反应失调致危及生命的疾病,具有发病率高、病死率高、发病机制复杂的特点,其早期诊断一直是医学研究的热点问题。目前,常用的脓毒症实验室指标无法提供病原微生物信息。小分子RNA(miRNA)是生物体生理和病理条件下存在的微小RNA,在不同的致病微生物感染患者中呈差异表达,为脓毒症的早期诊断提供了新方向。该文就miRNA在脓毒症病原微生物诊断中的应用综述如下。     

血流感染病原微生物诊断技术的研究与应用

血流感染(BSI)是指病原微生物侵入血液循环并在体内繁殖的一种全身感染性疾病。近年来因其高发病率及病死率而受到越来越多的关注,如何实现BSI致病菌的快速检测及其药敏结果的准确回报,是长期困扰临床的问题。血培养是诊断BSI病原微生物的"金标准",但其阳性率低且结果报告周期长,因此需探索新的技术以弥补此缺陷。近年来,微生物多种诊断技术,如阳性报警时间、核酸杂交技术、核酸扩增技术、质谱检测技术、基因芯片和测序技术等逐步从研究阶段走向BSI病原微生物诊断的临床应用阶段。本文旨在对BSI病原微生物基于全血标本和基于血培养的检测技术进行综述,为BSI病原微生物快速诊断和治疗提供方法学依据。     

脓毒症线粒体损伤研究进展

脓毒症(sepsis)是由病原微生物感染所致的全身炎性反应综合征,尽管目前对该疾病的病理生理有了进一步认识,其病死率仍居高不下,成为了重症医学的临床研究热点。大量研究表明严重脓毒症多器官功能障碍综合征(MODS)的发生与线粒体功能损伤关系密切。脓毒症时线粒体的损伤主要由线粒体内膜的损伤、线粒体钙超载、线粒体DNA的损伤等主要环节造成,本文就脓毒症线粒体损伤的机制、线粒体损伤后主要成分的改变及靶向治疗的研究进展进行阐述。     

脓毒症内皮细胞损伤和凝血功能障碍相关的生物标记物

脓毒症是宿主防御系统对入侵病原微生物产生的过度炎症反应.脓毒症的临床表现各不相同,疾病严重程度也受入侵的病原微生物、患者的遗传背景、共存疾病状态、临床干预时机和其他支持治疗手段的影响;同时发生急性器官功能障碍时被认为是重症感染;虽然经过充分的水化治疗,但仍不能维持血压而影响到组织灌注时被认为是感染性休克[1].重症感染是影响发病率和病死率的主要原因,也是重症监护病房(ICU)患者最主要的死亡原因.     

二代测序与重症感染的病原学诊断：路漫漫且修远

早期适当的抗生素治疗是降低重症感染患者病死率的关键,而正确鉴别病原微生物则是恰当的抗生素治疗的前提条件。然而,对于病原微生物的检测而言,绝大多数传统微生物学方法具有一定的目标性或指向性。当临床医生怀疑多种病原微生物并存时,可能需要同时进行多种微生物学的检查。近年来,二代测序（NGS）技术被应用于某些特殊病原微生物感染的诊治中。然而,作为一种新的实验室诊断技术,现有证据尚不足以支持NGS在临床上的常规应用。     

宏基因组高通量测序技术应用于感染性疾病病原检测中国专家共识

宏基因组高通量测序技术通过对临床样本中微生物和宿主核酸的测序分析,可以无偏倚地检测多种病原微生物,正在逐渐应用于临床感染性疾病病原检测,然而业界对该技术的临床适应证、实验流程、质量管理、性能验证和报告解读等方面仍有困惑。中华医学会检验医学分会临床微生物学组、中华医学会微生物学与免疫学分会临床微生物学组、中国医疗保健国际交流促进会临床微生物与感染分会组织专家对上述问题进行了讨论并撰写了专家共识,对一些关键问题给出了推荐意见和处理方法,希望有益于业界的良性互动,促进该技术规范和发展,为临床抗感染诊治提供帮助。     

环介导等温扩增技术在病原微生物临床检测中的应用

病原微生物是威胁人类健康的重要因素之一,快速、准确的检测方法对于感染性疾病的诊断具有重要意义。环介导等温扩增(LAMP)是一种恒温扩增方法,具有反应时间短、操作简便、灵敏度高、特异度高、检测成本低等优点,因此被广泛应用于感染性疾病的快速诊断。基于这种情况,该文主要阐述了LAMP的原理、特点及其在临床常见病原微生物检测方面的应用与研究进展。LAMP技术现在已经被应用于病原微生物的检测,且具有较高的灵敏度及特异度,但该技术仍有易产生假阳性、引物设计复杂等不足之处。该文综述了近年来LAMP技术在病原微生物感染中的应用与进展,并对其未来的发展前景进行了展望,以期在资源有限的环境中为病原微生物感染的快速诊断提供合理的研究方向。     

分子生物学技术应用于病原微生物分子分型的研究进展

病原微生物的分型检测在临床感染性疾病的诊断中发挥着重要作用。随着人类基因组计划的完成,分子生物学技术为病原微生物的分型检测提供了更多的分子靶点,进一步促进了病原微生物分型技术的发展,逐步取代了传统的分型方法。本文就近年来分子生物学技术应用于病原微生物分子分型的研究进行了综述。     

试纸型生物传感器检测病原微生物的研究进展

当今感染性疾病仍是引起人类死亡的主要原因,开展病原微生物的现场快速检测对疾病的治疗和预后尤为重要。目前,临床上主要使用的呼吸道病原体检测方法包括显微镜检查、细菌培养和免疫学试验,这些方法操作过程烦琐,耗时长,具有一定技术难度,灵敏度较低。随着分子生物学技术的飞速发展,DNA G+C mol%测定、特异探针杂交技术、PCR技术扩增特异核酸片段、16SrRNA序列分析、限制性片段长度多态性分析及生物芯片等技术被应用于病原微生物检测,这些方法的灵敏度和特异度高,并且能做到快速检测,但都依赖于昂贵的仪器设备及经过培训的实验室技术人员,这使其在小型社区医院及偏远地区的应用受到限制。     

中性粒细胞与脓毒症

中性粒细胞作为机体抗击病原微生物最重要的固有免疫细胞，从其粘附、渗出、活化到凋亡均对脓毒症发挥着重要作用。在脓毒症患者体内，中性粒细胞第一时间到达炎症部位，发挥吞噬病原微生物的作用，同时释放出一些生物活性物质（蛋白水解酶、花生四烯酸代谢产物、活性氧族和细胞因子等）以增强机体清除病原微生物的能力。     

数字聚合酶链反应(dPCR)技术在病原体基因检测应用中的研究进展

实时荧光定量聚合酶链反应（qPCR）的准确度和精密度容易受到很多因素的影响，数字聚合酶链反应（dPCR）作为一种新的分子定量技术，以其更高的敏感度、精密度、独立于标准曲线及更高的抗干扰能力等优点，近年来在病原体基因检测中逐渐兴起。该文将dPCR技术的特点、优势、不足及在病原体检测中的应用进行综述。     

Efficacy of CW-Doppler and duplex system examinations for the evaluation of extracranial carotid disease

The efficacy of different ultrasound methods for the detection of extracranial arterial disease (EAD) was evaluated on the basis of the comparison with angiography. High-resolution B-scan imaging combined with a multigated pulsed Doppler flow pattern analysis (Duplex system) achieved the best results for the detection of morphological and hemodynamic changes of nonstenotic lesions and low grade stenosis. However, a technically unsatisfactory examination rate of 19%, the failure to differentiate between total and subtotal carotid occlusions, underestimation of significant stenosis and impracticable vertebral flow studies were disadvantages of the Duplex technique. CW-Doppler examinations proved to be more precise and more reliable for the detection of significant stenosis and occlusions. Since vertebral blood flow studies were impractical with the Duplex system, CW-Doppler provides more comprehensive information about the hemodynamics of cerebral blood supply.     

SI06Protein Microarrays for Blood Typing and Testing

Microarrays, thanks to high multiplexing power, have a potential to accommodate various assays within one testing format. There are numerous variations of microarrays in relation to surfaces, probe deposition, inclusion of microfluidics, detection method etc. However, two key choices relate to microarray matrix (flat surface versus microparticle based microarrays) and, perhaps most importantly to the character of probe (DNA versus protein), determining genotypic or phenotypic character of the assay. There are two basic configurations for blood grouping and pathogen testing–antigen and antibody detection. Antigen detection–blood typing and pathogen antigen detection, are primarily phenotypic assays but can be determined by blood group antigen genotyping and pathogen nucleic acid amplification techniques (NAT). Detection of antibodies against relevant transfusion‐transmitted pathogens and rare antibodies against blood group antigens are exclusively phenotypic assays. Protein microarrays are capable of accommodating all types of assays. However, in some cases genotypic assays have higher precision and sensitivity. It remains to be seen if either approach (genotyping versus phenotyping) could solve the potential discrepancies completely, but a combination of the two types of arrays on one platform seems feasible in the future. Our initial efforts focused on ABO and Rh typing and resulted in the development of nonagglutination blood grouping array and label‐free detection of specifically bound erythrocytes on gold slides. Direct antiglobulin test has been shown to work on this array, too. In a parallel development we have investigated antibody and antigen microarrays for pathogen detection, focusing on mandatory targets – HIV, HCV, HBV and TP. While a gold surface is well suited for antibody–cell interactions, it is less so for antibody–antigen interactions taking place closer to the surface. A variety of slide surfaces and assay conditions were studied and applied successfully to antibody detection in a clean (spiked) assay. It was evident that pathogen antigen detection requires an increase in sensitivity. We have chosen signal amplification for this purpose and applied it successfully in a preliminary set of experiments. Although certain assays need further improvement the proof of concept studies confirmed suitability of protein arrays as the basis for potential next generation comprehensive blood testing platform.     

High-throughput screening of bacterial pathogens in clinical specimens using 16S rDNA qPCR and fragment analysis

Molecular-based detection of bacterial pathogens directly from clinical specimens permits rapid initiation of effective antimicrobial treatment and adequate patient management. Broad-range polymerase chain reaction (PCR) amplification of the 16S rRNA gene (16S rDNA qPCR) is used in many diagnostic laboratories as a complement to cultural identification of bacterial pathogens. However, efforts for automation of 16S rDNA PCR workflows are needed in order to reduce turnaround times and to enhance reproducibility and standardization of the technique. In this retrospective method evaluation study, clinical specimens (N?=?499) from patients with suspected bacterial infections were used to evaluate 2 diagnostic semiautomated workflows for rapid bacterial pathogen detection. The workflows included automated DNA extraction (QIASymphony), 16S rDNA qPCR, fragment or melting curve analysis, and amplicon sequencing. Our results support the use of the 16S rDNA qPCR and fragment analysis workflow as it enabled rapid and accurate identification of bacterial pathogens in clinical specimens.     

CT enterography of Crohn’s disease

CT enterography (CTE) is a technique using neutral oral contrast, intravenous contrast and thin cut, multiplanar CT acquisitions to optimize small bowel imaging. One of the primary indications for CTE is the detection and evaluation of Crohn’s disease. This article summarizes the advantages/disadvantages, scanning technique, imaging findings, performance and pitfalls of CTE for the evaluation of Crohn’s disease.     

Technique for the early detection of drug-resistant HBV DNA during antiviral therapy

Early detection of antiviral resistant mutants is of clinical importance in patients receiving antiviral treatment. The ideal assay is sensitive, specific, accurate, reproducible and easy to perform, attains a high throughput and is able to detect mixed and novel mutations. Advantages and disadvantages of sequencing, line probe assay, DNA chip technology, peptide nucleic acid cramping, fluorescent biprobe hybridization and a new technique based on matrix-assisted laser desorption/ionization time-of-flight mass-spectrometric analysis will be discussed.     

PCR检测儿童微小残留白血病的研究进展

微小残留白血病（MRD）是指白血病经化疗缓解后在骨髓中仍存在形态上不能检测到的白血病细胞,是白血病复发的主要原因。儿童MRD的检测对判断儿童白血病的预后、制定白血病的治疗方案有重要意义。PCR方法在MRD检测中具有快速、特异、简便、经济和样本量少等特点。本文综述近年以多重PCR初筛白血病靶基因,以荧光定量PCR（FQ-PCR）追踪MRD方面所取得的进展。     

The Delphi technique: a worthwhile research approach for nursing?

Since its introduction as a research approach in the late 1940s the Delphi technique has had over 1000 published research utilizations. Most of these have been in the field of social policy. However, a review of contemporary nursing literature suggests that it is becoming a popular choice among nurse researchers. With its focus on maximizing participant's judgements and decision-making abilities the Delphi technique is a useful tool in the research armoury of a young profession. However, questions remain about its scientific respectability. This paper gives an overview of what the Delphi technique is, the criteria for selecting it as a research approach, the studies where it has been used and its advantages and disadvantages.     

高通量测序技术在尿路感染及腹膜透析相关腹膜炎病原学诊断中的价值

目的 比较尿路感染、腹膜透析相关腹膜炎患者采用高通量测序技术、常规培养法对病原体的检出情况,探讨高通量测序技术在尿路感染、腹膜透析相关腹膜炎病原学诊断中的应用价值.方法 收集77例尿路感染患者中段尿标本,36例腹膜透析相关腹膜炎患者透析流出液标本,分别应用高通量测序技术、常规培养法进行检测,记录病原体检出率及病原体分布...     

Epidural analgesia and labor

Whilst women vary in their needs and desire for analgesia in labor it must be acknowledged that neuraxial analgesia is the only technique that can completely relieve the pain of labor. However the technique is not without its own inherent complications, both for the mother and for the process of labor and delivery. In this article the techniques for establishing and maintaining neuraxial analgesia in labor are discussed and the advantages and disadvantages of neuraxial analgesia in labor are explored.