基于化学发光肠道病毒71型IgM抗体检测试剂的研制及初步应用

目的在肠道病毒71型(EV71)重组外壳蛋白VP1的基础上建立以化学发光为基础的IgM抗体检测技术,并与普通TMB显色酶联免疫吸附法比较,评价其临床应用前景。方法采用抗IgM单克隆抗体及辣根酶标记的重组VP1抗原,在此基础上建立EV71-IgM捕获法化学发光检测技术,并对比化学发光检测技术与普通酶联检测技术在45份EV71抗体阳性和30份阴性血清中的反应情况。结果化学发光法、普通酶联免疫吸附法、市售EV71-IgM检测试剂分别能与38份、19份、26份EV71抗体阳性血清发生阳性反应,灵敏度分别为84.4%、42.2%和57.8%;化学发光法灵敏度显著高于其他两种,差异有统计学意义(P<0.05);3种检测方法与阴性血清均无阳性反应。结论在EV71-VP1重组抗原的基础上建立的EV71-IgM捕获法化学发光检测技术具有很高的灵敏度,并有很好的临床应用前景。     

Epitope mapping of the White Spot Syndrome Virus (WSSV) VP28 monoclonal antibody through combined in silico and in vitro analysis reveals the potential antibody binding site

White Spot Syndrome Virus (WSSV) infecting shrimp is an enveloped double-stranded DNA virus. The WSSV is a member of the genus Whispovirus. The envelope protein VP28 is the most investigated protein of WSSV. In the present study, the epitope mapping of the monoclonal antibody (MAb) C-33 was carried out. Based on the epitope mapping results, an antigen-antibody interaction model was derived. Peptide scanning and confirmation of epitopes of MAb C-33 were carried out using the sequence data. The MAb was reactive to the epitope of both recombinant VP28 and the whole virus. The results of the study indicated the presence of an epitope region. The epitope region is found positioned within two peptides, covering 13 amino acids. Framework and CDR (complementarity determining regions) of heavy and light chain (VH & VL) sequences showed identity to germline immunoglobulin sequences. The Web Antibody Modelling (WAM) selected for further evaluation based on a comparative analysis of WAM and Rosetta server-generated models of the Fv region. The docking study using WAM generated model revealed that the residues from LEU98 to GLY105 are active in antibody binding. The findings of this study could form a structural basis for further research in VP28 based diagnostics and therapeutics or vaccine discovery.     

人细小病毒B19IgM抗体间接ELISA检测方法的初步建立

目的：利用原核表达并纯化的人细小病毒B19（HPV B19）结构蛋白VP1初步建立HPV B19 IgM酶联免疫吸附试验（ELISA）的检测方法。方法以纯化的重组蛋白包被酶标板,建立IgM 间接ELISA检测方法,确定Cut-off值,并进行初步的应用。结果建立间接 ELISA方法Cut-off值为0．25,灵敏度为84．60％,特异性为99．70％,与对照试剂盒检测结果符合率为99．47％;用自产试剂盒检测115份孕妇和1700份健康献血志愿者血清中B19 IgM抗体,阳性率分别为12．17％和1．59％。结论通过包被 HPV B19-VP1蛋白建立的间接ELISA检测方法可用于 HPV B19早期感染或急性感染的辅助诊断。     

传染性法氏囊病病毒B87株VP2基因克隆及序列分析

目的获得传染性法氏囊病病毒（IBDV）B87株VP2基因,并对其序列进行分析。方法采用RT-PCR方法扩增传染性法氏囊病病毒B87株VP2基因,扩增产物提纯后克隆入pMD18-T载体,通过酶切、PCR和测序验证克隆,测序结果与GenBank下载的21株参考毒株VP2基因编码区全核苷酸序列进行比较。结果克隆的VP2基因序列长度为1536bp。所测B87株与Ⅰ型参考毒株的核苷酸同源性介于95.1%～99.2%之间,与Ⅱ型毒株的同源性仅为54.1%～54.7%。结论大多数IBDV强毒株、变异株、超强毒株与B87株的亲缘关系较远;诱导产生保护性中和抗体的VP2抗原决定簇的两个亲水区氨基酸变异较大,是逃避B87疫苗株的免疫保护、导致免疫失败而发生免疫鸡群传染性法氏囊病（IBD）流行的分子基础。     

Improved outcomes and complications of atrial fibrillation catheter ablation over time: learning curve, techniques, and methodology

Introduction and objectives

The outcomes of atrial fibrillation ablation procedures vary widely between different centers. Our objective was to analyze the results and complications of this procedure in our center and identify factors predicting the efficacy and safety of atrial fibrillation ablation.

Methods

In total, 726 atrial fibrillation ablation procedures were performed in our center between 2002 and 2009. Beginning in January 2008, a protocol for anticoagulation and conscious sedation was systematically applied. Outcomes and complications could therefore be compared in 2 well-differentiated groups: group A included 419 procedures performed prior to 2008 and group B included 307 procedures completed after 2008 using the new protocol.

Results

During an average follow-up of 8.7 months, 60.9% of patients were arrhythmia-free after one or repeat procedures. After only 1 procedure, the success rate was 41% and significantly higher in group B (51.6% vs 35.2% in group A; P=.001). There were 31 major complications (4.2%), 26 in group A (6.2%) and 5 in group B (1.6%) (P=.002). The implementation of the new protocol was an independent predictor of the absence of complications (odds ratio=0.406; 95% confidence interval, 0.214-0.769; P<.006).

Conclusions

Systematic application of an anticoagulation and conscious sedation protocol is associated with improved results and fewer complications of atrial fibrillation ablation. Factors not evaluated in the present study, such as operator experience and ongoing improvements in atrial fibrillation ablation technology, could have influenced these findings.Full English text available from:www.revespcardiol.org     

家养野猪源EMCV VP1基因的原核表达及其间接ELISA方法的建立和应用

目的以原核表达的脑心肌炎病毒(EMCV)VP1蛋白作为检测抗原,建立间接ELISA方法用来检测EMCV抗体。方法应用原核表达载体pET-28a构建家养野猪源EMCV VP1基因的重组表达质粒,并在感受态细胞BL21中表达,将该重组蛋白纯化后作为包被抗原,建立间接ELISA标准化检测程序,并应用于临床检测。结果经双酶切、PCR和测序鉴定,重组质粒pET-28a-VP1构建成功,转化后诱导表达,经SDS-PAGE电泳分析得到高效表达的VP1蛋白,该重组蛋白可被EMCV阳性血清特异性识别,具有良好的反应原性;通过优化反应条件,确定抗原浓度为1.25 ug/mL、待检血清以1∶80倍稀释为最佳抗原包被浓度和待检血清最佳稀释度,5%脱脂乳作为封闭液,待检血清的最佳作用时间为37 ℃作用60 min,酶标抗体稀释度的最佳工作浓度和最佳作用时间分别为1∶8 000和37 ℃ 30 min,底物最佳显色时间为20 min,特异性强,敏感性较高,重复性良好;应用该间接ELISA方法分别检测河南省126个猪场送检的1 618份血清和527份PCV-2抗体阳性血清,发现阳性场检出率为65.87%,血清总阳性率为45.30%,不同规模和不同阶段猪群均存在EMCV感染,中小型猪场的阳性率显著高于规模化猪场,EMCV与猪圆环病毒2型的混合感染率高达75.14%。结论应用原核表达的重组VP1蛋白作为包被抗原建立的间接ELISA方法可用于检测EMCV抗体水平,临床检测结果填补了河南省EMCV血清流行病学监测的空白。     

Meningitis caused by Enterococcus gallinarum in patients with ventriculoperitoneal shunts

Vancomycin-resistant enterococci have recently emerged as significant nosocomial pathogens. Here we describe two Japanese patients, a 57-year-old man and a 12-year-old boy, with ventriculoperitoneal shunts for hydrocephalus who developed meningitis caused by vancomycin-resistant Enterococcus gallinarum. The infection of the central nervous system in these two patients may have been associated with E. gallinarum derived from the gut. Removal of the shunts and antimicrobial treatment promoted apparent improvement in these patients. The risk factors and management of vancomycin-resistant enterococcal infections in the central nervous system are discussed.     

The VP1 structural protein of enterovirus 71 interacts with human ornithine decarboxylase and gene trap ankyrin repeat

Enterovirus 71 (EV71) is a major etiological agent of hand, foot and mouth disease (HFMD). Several outbreaks in East Asia were associated with neurological complications and numerous deaths. EV71 possesses four structural proteins VP1-VP4 that are necessary in the formation of the pentameric icosahedral capsid. The viral capsid contributes to virulence, and VP1 is a prime target for EV71 vaccine development. Using yeast two-hybrid analysis, we demonstrated binding affinity between VP1 and three human proteins, i.e. ornithine decarboxylase (ODC1), gene trap ankyrin repeat (GTAR), and KIAA0697 expressed in brain tissue. These interactions were authenticated by co-immunoprecipitation experiments, and by indirect immunofluorescent confocal microscopy of transfected and EV71-infected Vero cells. The significant interaction between VP1 and ODC1 may compromise the latter's activity, and interfere with polyamine biosynthesis, growth and proliferation of EV71-infected cells. The interaction between VP1 and GTAR is noteworthy, since ankyrin proteins are associated with certain neural cell adhesion molecules and with the CRASH neurological syndrome. Given that VP1 is synthesized in large amounts during productive infection, these viral-host protein interactions may provide insights into the role of VP1 in the pathogenesis of EV71 disease and its neurological complications such as acute flaccid paralysis and encephalitis.     

Sequence analysis of a canine parvovirus isolated from a red panda (<Emphasis Type="Italic">Ailurus fulgens</Emphasis>) in China

Canine parvovirus (CPV) was first recognized in the late 1970 s in dogs and has mutated and spread throughout the world in canid and felid species since then. In this study, a novel CPV was isolated from the endangered red panda (Ailurus fulgens) in China. Nucleotide and phylogenetic analysis of the capsid protein VP2 gene classified the red panda parvovirus (RPPV) as a CPV-2a type. Substitution of Val for Gly at the conserved 300 residue in RPPV presents an unusual variation in the CPV-2a amino acid sequence and is further evidence for the continuing evolution of the virus. The 300 residue is important in distinguishing the antigenicity and host range of CPVs. The clinical significance and population impact of RPPV infection in captive red pandas in China is unknown and is an important topic for future research.     

2D-DIGE蛋白质组技术的探讨及其在微生物研究中的应用

目的:探讨双向差异凝胶电泳(two dimension difference gel electrophoresis,2D-DIGE)的实验方法,分析比较其优缺点,概述其在微生物研究中的应用。方法:以两株不同血清型的副溶血性弧菌为样本,通过2D-DIGE实验,得到两组蛋白质荧光染色分布图,与银染的效果比较。结果:直观的看到两株细菌的蛋白质差异,且可分析样品丰度变化。结论:该方法有一定的局限性,但却是研究蛋白质组丰度变化的强有力工具。