兔出血症病毒抗体的实验室检测能力验证结果评价

目的通过兔出血症病毒抗体检测能力验证计划,了解实验动物检测机构检验能力,提高实验动物质量检测水平。方法按照CNAS批准的能力验证方案,通过筛选血清制备样品,经过稳定性和均匀性检验合格,作为能力验证样品。采用随机编号,发样给参加单位,并附作业指导书。在规定时限提交检验报告和原始记录复印件,其结果与样品预检结果一致的判为满意结果,不一致或未能提交结果的判为不满意结果。结果来自14个省市自治区的20个实验室报名参加本次比对实验,均在规定时间内反馈了检测结果,17个实验室检测结果为合格或优秀,占参加比对实验室的85%。在20个实验室中,14个实验室采用了酶联免疫吸附实验(ELISA)方法,6个实验室采用血凝抑制实验(HAI)方法。结论全国各实验动物检测机构兔出血症病毒抗体总体检测能力较高,实施能力验证计划能够反映实验室的检测水平。     

实验小鼠肾匀浆中酯酶-3的实验室测定能力验证结果评价

目的通过实验小鼠肾匀浆中酯酶-3项目的检测比对,了解全国实验动物质量检测实验室的水平,促进各实验室加强质控。方法按照CNAS批准的能力验证方案,制备样品并将稳定性和均匀性合格的样品作为能力验证样品,进行随机编号,随作业指导书一起发放给参加单位。在规定时限提交检验报告和原始记录复印件,其结果与样品预检结果完全一致的判为优秀结果;除杂合型判定以外的结果均一致的判定为满意结果,否则判为不满意结果。结果共10个实验室报名参加本次比对试验,其中优秀结果 0个实验室;满意结果的有9个实验室,占参加比对实验室的90.0%;不满意结果 1个实验室,占参加比对实验室的10.0%。结论本次能力验证项目反映了各参与实验室在实验小鼠肾匀浆中酯酶-3的总体检测能力较高,但检测细节及部分实验室技术水平还有待提高。     

参加临检中心乙肝免疫学检验5年总结

为了全面提高乙肝标志物检验水平,卫生部临床检验中心(NCCL)免疫质控室从1988年开始在全国范围内开展乙肝标志物检验的室间质量评价(EQA)活动,全国300多家医院实验室参加,我科免疫室1990～1994年参加全国乙肝检验EQA活动,现总结如下。1　材料与方法1.1　室间质控血清　NCCL免疫质控室每季度将质评血清用邮寄方式发至参加EQA的实验室,每批包括5支质控血清,分别检出HBsAg、抗HBs、HBeAg、抗HBe、抗HBc,其中抗HBc按NCCL要求进行原倍血清和稀释血清后检测,以供流行病学和临床意义分析。按期检测并在规定日期内将检测结果寄至NCC…     

聚合酶链反应在真菌性水(脓)疱诊断难辨认癣中的应用CSCD

目的分析聚合酶链反应(polymerase chain reaction,PCR)在真菌性水(脓)疱诊断难辨认癣中的临床价值。方法纳入34例2020年7月—2021年10月就诊于我院(上海市皮肤病医院)门诊表现为水(脓)疱难辨认癣的患者,对34例患者的疱液标本进行PCR检测,并通过荧光染色镜检、真菌培养等进行对比。结果共收集34例患者的疱液标本,荧光染色镜检、真菌培养和PCR的敏感性分别为100%、77.8%和100%,特异性分别为87.5%、100%和75%,阳性预测值分别为90%、100%和81.8%,阴性预测值分别为100%、80%和100%,准确度分别为94.1%、88.2%和88.2%。疱液提取DNA、PCR扩增和测序比对在12 h内完成,鉴定出6种22例真菌(1例鉴定到属)。结论在真菌性水(脓)疱诊断难辨认癣中,PCR有较好的敏感性和准确度。PCR相较真菌镜检能判定真菌种类,相较真菌培养能缩短时间,能为难辨认癣的临床快速诊断与及时治疗提供参考价值。     

环凯食(饮)具大肠菌群检验纸片检测能力测试研究*

研究以营养琼脂培养基的计数结果为基准,采用由卫生部食检所监制的两种不同厂家生产的食(饮)具大肠菌群检验纸片作为对照,对环凯食(饮)具大肠菌群检验纸片进行了检测能力测试研究。在测试中采用1Ocells/mL,50cells/mL和1OOcells/mL3个不同菌液浓度,环凯纸片的检测结果和营养琼脂平板计数结果基本一致,与其它两种纸片的检测结果无明显差异,完全可以用于食(饮)具大肠菌群的监督检验。     

实验动物金黄色葡萄球菌的实验室检测能力验证结果评价

目的通过实施实验动物金黄色葡萄球菌检出能力验证计划,了解实验动物检测机构检验能力,提高实验动物质量检测水平。方法按照CNAS批准的能力验证方案,通过低温冻干制备样品,经过稳定性和均匀性检验合格,作为能力验证样品。采用随机编号,发样给参加单位,并附作业指导书。在规定时限提交检验报告和原始记录复印件,其结果与样品预检结果一致的判为满意结果,不一致或未能提交结果的判为不满意结果。结果共有28个实验室参加本次能力验证项目,其中获得满意验证结果的实验室为22个,占总参加机构的78.57%;未得到满意验证结果的实验室为6个,占21.43%。采用国标检测方法的有27个,采用PCR检测方法的有1个。结论实验动物质量检测机构对金黄色葡萄球菌的检测能力较高,实施能力验证计划能够反映实验室的检测水平。     

时间对微生物标本检验阳性率的影响分析

目的:对不同检验时间的临床微生物标本的阳性率进行探讨。方法:回顾性分析我院2013年12月至2014年5月间住院治疗的2106例患者在不同检验时间进行临床微生物检验的临床资料。结果:第一时间血培养标本、非呼吸道标本的阳性检出率明显高于第二时间(10.23%/6.25%、35.16%22.14%),差异有统计学意义(P0.05);且第一时间呼吸道标本阳性率明显低于第二时间呼吸道标本的阳性率(28.92%/36.29%),差异有统计学意义(P0.05);但两时间粪便标本阳性率相同,均为2.40%。结论:对于临床微生物标本应尽量做到立即送检,以减少微生物繁殖、厌氧菌的过度生长等对微生物检验准确性的影响;同时,要加强临床检验人员专业素养、提升技术水平,从而提高微生物检验质量,为感染性疾病的诊治提供有利依据。     

血清(1,3)-β-D葡聚糖与尿真菌培养联合检测对泌尿系侵袭性真菌感染的诊断价值

目的探讨血清(1,3)-β-D葡聚糖与尿真菌培养联合检测对泌尿系侵袭性真菌感染(IFI)的诊断价值。方法选取疑似泌尿系IFI患者157例,根据临床诊断,分为IFI组(48例)和非IFI组(109例),进行血清(1,3)-β-D葡聚糖检测(G试验)和尿真菌培养,比较两种方法单独和联合检测对泌尿系IFI诊断的灵敏度、特异度、阳性预测值、阴性预测值和Youden指数。结果 G试验和尿真菌培养的灵敏度、特异度、阳性预测值、阴性预测值和Youden指数依次为(87.5%、89.6%)、(77.1%、78.9%)、(62.7%、65.2%)、(93.3%、94.5%)和(0.646、0.685);联合检测的灵敏度、特异度、阳性预测值、阴性预测值和Youden指数依次为79.2%、98.2%、95.0%、91.5%和0.774。三者均具有较高阴性预测值,而联合检测的特异度、阳性预测值和Youden指数明显高于单独检测,差异有统计学意义(Ps0.05)。结论 G试验与尿真菌培养联合检测诊断泌尿系IFI具有较高的阴性预测值和阳性预测值,减少了假阳性结果,较单独检测具有更大的诊断价值。     

胃病患者胃黏膜真菌感染的检测

通过检测胃炎和胃溃疡、胃癌患者胃黏膜寄居的真菌,了解胃黏膜真菌的菌种多样性及其与胃溃疡的关系。采集消化科就诊患者胃镜钳取的胃黏膜标本63例,采用念珠菌显色培养基(CHROMagar)进行真菌分离培养鉴定。用玉米吐温80培养基进行真菌孢子形态学检查,用ITS(internal transcribed spacer region)序列限制性片段长度多态性(Restriction fragment length polymorphism,RFLP)检测分析真菌菌种多样性。分离培养真菌32(32/63,50.8%)株,经ITS序列RFLP法鉴定为白假丝酵母菌31株,光滑假丝酵母菌1株。真菌阳性率与病理诊断成正相关(r=0.263,P=0.027),与性别、年龄、吸烟、饮酒、学历的相关性均无统计学意义(P0.05)。结果表明,胃黏膜寄居的真菌存在多样性,且真菌阳性率与病理损害程度存在相关性。     

实验动物中沙门菌的实验室检测能力验证的结果与分析

目的通过实验动物中沙门菌检测能力验证计划,了解实验动物检测机构对沙门菌的检验能力,提高实验动物质量检测水平。方法按照CNAS批准的能力验证方案,通过冷冻干燥法制备含有沙门菌及干扰菌的实验动物粪便样品,经过稳定性和均匀性检验合格,作为能力验证样品。采用随机编号,经冷链运输发放给参加单位,并附作业指导书。在规定时限提交检验报告和原始记录复印件,其结果与样品预检结果一致的判为满意结果,不一致或未能提交结果的判为不满意结果。结果全国共有20个省市的30个实验室参加沙门菌能力验证项目,其中28个实验室获满意结果,占总参加机构的93.3%,不满意的2个实验室,占6.7%。采用分离培养方法的有29个实验室,采用PCR方法的有2个实验室。结论实验动物质量检测机构沙门菌检测能力较高,实施能力验证计划能够反映实验室的检测水平。     

糖尿病酮症酸中毒并社区获得性肺炎临床分析

目的:探讨糖尿病酮症酸中毒合并社区获得性肺炎的临床特点、治疗方法,为临床预防和治疗提供方法。方法:对2013年1月~2014年11月入住我院呼吸科病房的12例糖尿病酮症酸中毒合并社区获得性肺炎患者的临床资料、治疗、转归进行回顾性分析。结果:糖尿病酮症酸中毒合并社区获得性肺炎的患者危险因素有:意识状态、肺部基础疾病、贫血、低蛋白血症、血糖水平及降糖药物使用情况、年龄。经充分补液、小剂量胰岛素消酮、控制血糖、抗感染、呼吸机辅助通气、纠正离子紊乱及加强对症支持治疗后患者均好转出院。结论:在糖尿病酮症酸中毒合并社区获得性肺炎患者的诊治过程中,控制血糖是治疗的基础,抗感染是治疗的关键,同时改善营养和其他器官的功能状态可明显提高治愈率和降低病死率。     

Cytoplasmic Membrane-Associated Protein (CAP) Isolated from Streptococcus pyogenes: As a New Bacterial Superantigen

A protein isolated from the cytoplasmic membranes of Streptococcus pyogenes (cytoplasmic membrane-associated protein, CAP) stimulated human T cells in vitro to induce their mitogenic response. This CAP-induced T cell proliferation required the presence of nylon-adherent accessory cells (AC) of either autologous or allogeneic origin in the reaction mixtures. In addition, the reaction was inhibited by monoclonal antibodies (mAbs) against major histocompatibility complex (MHC) class II molecules, HLA-DR and -DQ, but not -DP. Human lymphoid cell lines positive for HLA-DR but not those lacking it were also effective as AC for the reaction. A binding test using fluorescein-labeled protein revealed that CAP bound to the adherent monocytes and HLA-DR⁺ but not to -DR^– lymphoid cell lines. The proliferative response of T cells to CAP was, however, not inhibited by the addition of the lysosomotrophic agent NH₄Cl to the reaction mixtures. These results suggest that the presentation of CAP by AC to human T cells is mediated through binding of the protein to the MHC class II molecules but without being processed in the AC. The proliferative response of T cells was also found to be inhibited by addition of anti-CD2, -CD3 or -T cell receptor (TcR) mAbs. A major population responding to CAP was CD3⁺4⁺8^– T cells. CAP also appears to stimulate T cells bearing Vβ8 sequences much more selectively than T cells bearing other Vβs. These results indicate that this streptococcal membrane protein, CAP, may be a new protein belonging to a group of bacterial superantigens.     

氯霉素在罗非鱼体内的代谢和消除规律

水产养殖动物口服氯霉素后可能在可食组织中造成残留,本文通过以50mg/kg鱼体重的氯霉素(CAP)的剂量对尼罗罗非鱼单次口灌给药,采用HPLC和GC-ECD分析方法研究了CAP在罗非鱼体内的代谢和消除规律。给药0.5h后,CAP在血浆和肝脏中的浓度均迅速上升,分别为4288.01±1285.53ng/mL和5214.18±1105.62ng/g,2h达到峰值22246.42±355.84ng/mL和25717.47±1740.66ng/g;而肌肉中CAP却上升较慢,2h仅为7744.08±2118.74ng/g,8h才达到峰值13232.89±1612.74ng/g,峰值仅约为血浆和肝脏的1/2。CAP在罗非鱼肌肉和肝脏中的消除速度均较慢,但肌肉比肝脏稍快,肌肉中第96d CAP降至为0.07±0.01ng/g,而肝脏中第120d尚在0.1ng/g以上,为0.25±0.06ng/g。肌肉和肝脏浓度常用对数-时间消除曲线方程分别为y=-0.0966x+5.4292;y=-0.053x+4.7258,二者的T1/2β为7.14d和13.08d。若要使CAP在罗非鱼肌肉和肝脏中的浓度降至0.1ng/g以下,则休药期分别需80.47d和132.61d。试验表明CAP在罗非鱼组织中消除缓慢,尤其在肝脏中,因此肝脏可以作为CAP残留监测的首选组织。       

Direct competitive chemiluminescence immunoassays based on gold‐coated magnetic particles for detection of chloramphenicol

Direct competitive chemiluminescence immunoassays (CLIA) based on gold‐coated magnetic nanospheres (Au‐MNPs) were developed for rapid analysis of chloramphenicol (CAP). The Au‐MNPs were modified with carboxyl groups and amino groups by 11‐mercaptoundecanoic acid (MUA) and cysteamine respectively, and then were respectively conjugated with CAP base and CAP succinate via an activating reaction using 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N‐hydroxysuccinimide (NHS). NSP‐DMAE‐NHS, a new and effective luminescence reagent, was employed to label anti‐CAP antibody (mAb) as a tracer in direct CLIA for CAP detection using a ‘homemade’ luminescent measurement system that was set up with a photomultiplier tube (PMT) and a photon counting unit linked to a computer. The sensitivities and limits of detection (LODs) of the two methods were obtained and compared according to the inhibition curves. The 50% inhibition concentration (IC₅₀) values of the two methods were about 0.044 ng/mL and 0.072 ng/mL respectively and LODs were approximately 0.001 ng/mL and 0.006 ng/mL respectively. To our knowledge, they were much more sensitive than any traditional enzyme‐linked immunosorbent assay (ELISA) ever reported. Moreover, the new luminescence reagent NSP‐DMAE‐NHS is much more sensitive and stable than luminol and its derivatives, contributing to the sensitivity enhancement. Copyright © 2015 John Wiley & Sons, Ltd.     

一株氯霉素降解细菌的分离鉴定与代谢特性研究

微生物是介导环境中氯霉素降解转化的主要驱动者,但高效降解矿化菌株资源匮乏,氧化反应介导的代谢途径不清。为研究微生物介导下氯霉素的环境归趋过程,为氯霉素污染环境强化修复提供菌株资源,文中以受氯霉素污染的活性污泥为接种源,首先富集获得一个由红球菌Rhodococcus主导 (相对丰度>70%) 的氯霉素高效降解菌群,并从中分离获得一株能够高效降解氯霉素的菌株CAP-2,通过16S rRNA基因分析鉴定为红球菌Rhodococcus sp.。菌株CAP-2能在不同营养条件下高效降解氯霉素。基于菌株CAP-2对检测到的代谢产物对硝基苯甲酸和已报道的代谢产物对硝基苯甲醛和原儿茶酸的生物转化特征,提出其降解途径是由氯霉素侧链氧化断裂生成对硝基苯甲醛,进一步氧化为对硝基苯甲酸的新型氧化降解途径。该菌株对于氯霉素分解代谢的分子机制研究以及受氯霉素污染环境的原位生物修复应用具有巨大潜力。     

Kinetics of c-reactive protein (CRP) and serum amyloid A protein (SAA) in patients with community-acquired pneumonia (CAP), as presented with biologic half-life times

Context: In management of community-acquired pneumonia (CAP), excellent biomarkers for inflammation would be helpful in our practice.

Objectives: Kinetics of c-reactive protein (CRP) and serum amyloid A (SAA) was characterized, using their biologic half-life times.

Materials and methods: Time course of CRP and SAA levels in the successfully treated 36 CAP patients were investigated and their half-life times were determined and compared.

Results & Discussions: SAA and CRP declined in an exponential mean and the biologic half-life times of SAA levels was 34.9?±?28.7?h, significantly shorter than that of CRP, 46.4?±?21.7?h (p?=?0.0014). Conclusion: The kinetic evidence, presented as biologic half-life times of CRP and SAA, helps us make a clinical assessment of CAP patients.     

Probing the binding mechanism of capecitabine to human serum albumin using spectrometric methods,molecular modeling,and chemometrics approach

Capecitabine as a prodrug of 5-Fluorouracil plays an important role in the treatment of breast and gastrointestinal cancers. Herein, in view of the importance of this drug in chemotherapy, interaction mechanism between Capecitabine (CAP) and human serum albumin (HSA) as a major transport protein in the blood circulatory system has been investigated by using a combination of spectroscopic and molecular modeling methods. The fluorescence spectroscopic results revealed that capecitabine could effectively quench the intrinsic fluorescence of HSA through a static quenching mechanism. Evaluation of the thermodynamic parameters suggested that the binding process was spontaneous while hydrogen bonds and van der Waals forces played a major role in this interaction. The value of the binding constant (K_b = 1.820 × 10⁴) suggested a moderate binding affinity between CAP and HSA which implies its easy diffusion from the circulatory system to the target tissue. The efficiency of energy transfer and the binding distance between the donor (HSA) and acceptor (CAP) were determined according to forster theory of nonradiation energy transfer as 0.410 and 4.135 nm, respectively. Furthermore, UV–Vis spectroscopic results confirmed that the interaction was occurred between HSA and CAP and caused conformational and micro-environmental changes of HSA during the interaction. Multivariate curve resolution-alternating least square (MCR-ALS) methodology as an efficient chemometric tool was used to separate the overlapped spectra of the species. The MCR-ALS result was exploited to estimate the stoichiometry of interaction and to provide concentration and structural information about HSA-CAP interactions. Molecular docking studies suggested that CAP binds mainly to the subdomain IIA of HSA, which were compatible with those obtained by experimental data. Finally, molecular dynamics simulation (MD) was performed on the best docked complex by considering the permanence and flexibility of HSA-CAP complex in the binding site. MD result showed that CAP could steadily bind to HSA in the site I based on the formation of hydrogen bond and π-π stacking interaction in addition to hydrophobic force.     

Severity of Influenza A 2009 (H1N1) Pneumonia Is Underestimated by Routine Prediction Rules. Results from a Prospective,Population-Based Study

Background

Characteristics of patients with community-acquired pneumonia (CAP) due to pandemic influenza A 2009 (H1N1) have been inadequately compared to CAP caused by other respiratory pathogens. The performance of prediction rules for CAP during an epidemic with a new infectious agent are unknown.

Methods

Prospective, population-based study from November 2008–November 2009, in centers representing 70% of hospital beds in Iceland. Patients admitted with CAP underwent evaluation and etiologic testing, including polymerase chain reaction (PCR) for influenza. Data on influenza-like illness in the community and overall hospital admissions were collected. Clinical and laboratory data, including pneumonia severity index (PSI) and CURB-65 of patients with CAP due to H1N1 were compared to those caused by other agents.

Results

Of 338 consecutive and eligible patients 313 (93%) were enrolled. During the pandemic peak, influenza A 2009 (H1N1) patients constituted 38% of admissions due to CAP. These patients were younger, more dyspnoeic and more frequently reported hemoptysis. They had significantly lower severity scores than other patients with CAP (1.23 vs. 1.61, P = .02 for CURB-65, 2.05 vs. 2.87 for PSI, P<.001) and were more likely to require intensive care admission (41% vs. 5%, P<.001) and receive mechanical ventilation (14% vs. 2%, P = .01). Bacterial co-infection was detected in 23% of influenza A 2009 (H1N1) patients with CAP.

Conclusions

Clinical characteristics of CAP caused by influenza A 2009 (H1N1) differ markedly from CAP caused by other etiologic agents. Commonly used CAP prediction rules often failed to predict admissions to intensive care or need for assisted ventilation in CAP caused by the influenza A 2009 (H1N1) virus, underscoring the importance of clinical acumen under these circumstances.     

Heligmosomoides polygyrus Venom Allergen-like Protein-4 (HpVAL-4) is a sterol binding protein

Heligmosomoides polygyrus bakeri is a model parasitic hookworm used to study animal and human helminth diseases. During infection, the parasite releases excretory/secretory products that modulate the immune system of the host. The most abundant protein family in excretory/secretory products comprises the venom allergen-like proteins (VALs), which are members of the SCP/TAPS (sperm-coating protein/Tpx/antigen 5/pathogenesis related-1/Sc7) superfamily. There are >30 secreted Heligmosomoides polygyrus VAL proteins (HpVALs) and these proteins are characterised by having either one or two 15?kDa CAP (cysteine-rich secretory protein (CRISP)/antigen 5/pathogenesis related-1) domains. The first known HpVAL structure, HpVAL-4, refined to 1.9?Å is reported. HpVAL-4 was produced as a homogeneously glycosylated protein in leaves of Nicotiana benthamiana infiltrated with recombinant plasmids, making this plant expression platform amenable for the production of biological products. The overall topology of HpVAL-4 is a three layered αβα sandwich between a short N-terminal loop and a C-terminal cysteine rich extension. The C-terminal cysteine rich extension has two strands stabilized by two disulfide bonds and superposes well with the previously reported extension from the human hookworm Necator americanus Ancylostoma secreted protein-2 (Na-ASP-2). The N-terminal loop is connected to alpha helix 2 via a disulfide bond previously observed in Na-ASP-2. HpVAL-4 has a central cavity that is more similar to the N-terminal CAP domain of the two CAP Na-ASP-1 from Necator americanus. Unlike Na-ASP-2, mammalian CRISP, and the C-terminal CAP domain of Na-ASP-1, the large central cavity of HpVAL-4 lacks the two histidines required to coordinate divalent cations. HpVAL-4 has both palmitate-binding and sterol-binding cavities and is able to complement the in vivo sterol export phenotype of yeast mutants lacking their endogenous CAP proteins. More studies are required to determine endogenous binding partners of HpVAL-4 and unravel the possible impact of sterol binding on immune-modulatory functions.