3种霍乱弧菌检测方法在外环境标本中的应用研究

目的：通过改进霍乱弧菌检测的技术手段，提高外环境标本中霍乱弧菌的检出率。方法：将常规分离鉴定法、PCR检测法和胶体金免疫层析试验法同时用于检测霍乱流行期间的外环境标本，并对其现场应用结果进行比较分析。结果：3种方法检测80份外环境标本霍乱弧菌的结果显示：它们均未出现假阳性，3种方法各有优势，且结果相互符合性好，但也存在各自弱点。结论：只用单一种方法来检测外环境标本霍乱弧菌存在明显不足。建议在外环境霍乱监测中选用胶体金法进行初筛，再用常规法和PCR法检测。最大限度减少漏检的可能性。     

El Tor型霍乱弧菌L型的某些生物学性状

本研究主要对El Tor型霍乱弧菌(Vibrio cholerae biotvpe eltor,EVC)L型的某些生物学特性如生化反应、抗生素敏感性及超微结构等进行了探讨.研究发现EVC不稳定L型的生化性状与EVC流行株的非常相似,而稳定L型则变化很大.抗生素敏感性试验显示EVC稳定L型对某些作用于细胞壁的抗生素的敏感性减弱,而对大多数作用于蛋白质合成的抗生素的敏感性增强.与流行株相比,EVC稳定L型和不稳定L型的超微结构的改变很明显.此外,本文还讨论了产生这些改变的可能机制.     

Purification and partial characterization of fimbriae of Vibrio cholerae O1

Fimbriae of Vibrio cholerae O1 were purified from a strain of the classical biotype, Inaba serotype (Bgd 17), and a strain of the El Tor biotype, Ogawa serotype (K23), grown on TCG agar medium by the following procedure; homogenization of the cell suspension to detach fimbriae, ultracentrifugation to remove remaining cells and their debris, concentration of the supernatant containing fimbriae with ultrafiltration, and 20 to 40% sucrose linear gradient centrifugation of the concentrated material. The fimbriae in both preparations were flexible, long fibres readily distinguishable under the electron microscope from those of CFA/I, CFA/II seen in ETEC strains. Their structural subunit was a protein of 16 kdaltons. Fimbriae isolated from both serotypes and biotypes shared antigenic determinants.     

衡阳市城区市售甲鱼中检测霍乱弧菌的采样调查

目的了解衡阳市城区市售甲鱼中有无霍乱弧菌的感染。方法共采样55份，其中甲鱼肛门涂抹样36份，甲鱼表面粘液涂抹样19份。采用霍乱弧菌食物中毒的国家标准的检验方法进行检测。结果衡阳市市售甲鱼55份样本中有1份检测出O139血清型霍乱弧菌的感染。结论需采取相应的预防措施以防止霍乱弧菌引起的疫情。     

副溶血弧菌染色体DNA指纹图及其质粒图谱研究

对不同来源、不同血清型的７１株副溶血弧菌染色体ＤＮＡ指纹图及其质粒图谱进行了分析研究。结果表明：不同血清型、不同来源菌株的ＤＮＡ指纹图有显著的不同，相同血清型而来源不同的菌株其ＤＮＡ指纹图亦有区别，来自同一起暴发的同一克隆菌株的ＤＮＡ指纹图则极为相似，而且该ＤＮＡ指纹图具有极好的稳定性和精确性。质粒分析显示，其检出率为８７．３２％，且图谱呈多样性，但未发现质粒分布与血清型及来源的相关性。     

肠道革兰氏阴性杆菌及孤菌快速鉴定的研究

目的：为寻求肠道G杆菌及弧菌快速鉴定的方法。方法：菌种经增菌及分离培养后，取菌落接种于综合生化培养基，并在综合生化培养基管口悬挂硫化氢和靛基质试纸条。同时以克氏双糖铁培养基作对照，置37℃培养18-24h。取综合生化管培养基，外加测试氧化酶，共获取11项生化指标。结果：对689株不同菌种与综合生化管培养基和常规双糖铁培养的测试结果，符合率为99．97％，(7577/7579)和99．79％(7563/7579)。结论：综合生化管是适合医疗卫生单位微生物实验室的一种快速检验方法。     

Comparative proteomic analysis of Vibrio cholerae O139, O22, O155 and El Tor biotype epidemic strains

Cholera ,as one of the most severe epidemic dis-eases inthe world,can occurin a short time ,andspread quicklyto a wide region.Until 1992 ,onlyV.choleraeserogroup O1 was recognized as thecause of epidemic cholera . However in October1992 ,a major outbreak of a cholera-like illnesscaused by a newserogroupstrain ofV.choleraee-mergedinIndia and Bangladesh.In contrast to allpreviously reported non-O1 strains , which induceonly sporadic cases of human diarrhea without epi-demic potential ,the new…     

Proteomic analysis of salt-sensitive outer membrane proteins of Vibrio parahaemolyticus

Vibrio parahaemolyticus, a universal marine pathogen with available genome sequences, could be used as a bacterial model to clarify the various physiological phenomena of its native and host environments. In the present study, proteomic methodologies were applied to investigate the expression pattern of outer membrane proteins (OMPs) of V. parahaemolyticus at different NaCl concentrations. OmpW, OmpV, elongation factor TU and polar flagellin were determined to be osmoregulation-sensitive OMPs, among which OmpW and OmpV were reported to vary with changed NaCl concentrations in the pattern of osmolarity regulation. Therefore, our results not only expand our knowledge on osmoregulation-related proteins, but also provide a valuable strategy for the screening of salt-sensitive proteins.     

双重实时PCR快速同时检测霍乱弧菌和副溶血弧菌

目的建立改良分子信标双重实时PCR同时检测霍乱弧菌和副溶血弧菌的快速方法,应用于霍乱监测、副溶血弧菌食物中毒的快速诊断和海产品检验。方法根据GenBank公布的霍乱弧菌肠毒素基因A亚单位(ctxA)和副溶血弧菌的耐热直接溶血毒素基因(TDH)的保守序列,分别设计引物和改良分子信标探针,以10种细菌作对照,建立双重实时PCR改良分子信标检测体系,应用于副溶血弧菌食物中毒快速诊断和霍乱监测。结果改良分子信标双重实时PCR反应体系DNA灵敏度为102.4～166.6fgμl,菌液灵敏度为32～64CFUml或3～6CFUPCR反应体系,无交叉反应。此反应体系同时检测40株副溶血弧菌和50株霍乱弧菌,均出现特异的荧光信号,两种细菌检测互不干扰。对3起细菌性食物中毒共48份样品和100份海产品进行检测,9份副溶血弧菌实时PCR阳性,其中7份副溶血弧菌细菌培养阳性,其余样品都为阴性。从样品处理到检测结果仅需1天时间。结论改良分子信标双重实时PCR检测体系快速、灵敏度高、特异性强,可用于霍乱和副溶血弧菌食物中毒的快速诊断,为食源性疾病的分子流行病学调查提供新的检测手段。     

Contribution of the tdh 1 gene of Kanagawa phenomenon-positive Vibrio parahaemolyticus to production of extracellular thermostable direct hemolysin

Kanagawa phenomenon-positive strains of Vibrio parahaemolyticus contain two copies of the tdh gene (tdh1 and tdh2) encoding thermostable direct hemolysin (TDH). Previous studies suggested that the tdh2 gene, but not the tdh1 gene, was responsible for production of extracellular TDH. In this study, a tdh2-deficient isogenic mutant of Kanagawa phenomenon-positive strain AQ3815 was constructed by a suicide vector-mediated in vivo recombination method. The intact tdh1 gene in the mutant contributed little to Kanagawa phenomenon on Wagatsuma agar but produced TDH in broth media, accounting for 0.5–9.4% of total extracellular TDH of AQ3815.