吉林省小肠结肠炎耶尔森氏菌生物学特性研究

目的 了解吉林省小肠结肠炎耶尔森氏菌生物学特性。方法 利用血清学、生物化学、分子生物学技术对78株检出菌进行分析。结果 78株小肠结肠炎耶尔森氏菌分出O：3和O：9两个血清型，生物型为3型；毒力基因分布特征为ail^＋、ystA^＋、ystB^-、yadA^＋、virF^＋占60．0％，ail^＋、ystA^＋、ystB^-、yadA^-、virF^-占26．2％，其他型占13．8％；脉冲场凝胶电泳（PFGE）分出2个克隆系7个基因型。结论 利用上述方法能很好分析吉林省小肠结肠炎耶尔森氏菌生物学特性，探讨小肠结肠炎耶尔森氏菌遗传关系，追踪传染源。     

浙江省部分地区小肠结肠炎耶尔森菌(动物株)分子生物学特征初探

目的：了解浙江省部分地区小肠结肠炎耶尔森菌的血清型别、毒力基因分布等情况。方法：利用常规细菌分离方法从家禽、家畜和鼠类粪便标本中分离小肠结肠炎耶尔森菌，并进行毒力基因检测，同时对血清型O：3、O：5和O：8的菌株进行脉冲场凝胶电泳分析。结果：2004～2005年，从全省各点采集的动物标本中共分离到22株小肠结肠炎耶尔森菌，分布于11个血清型，并以O：8和O：3为主。PCR检测将分离到的22株小肠结肠炎耶尔森菌毒力携带情况分为4型：Ⅰ型（ail^＋、ystA^＋、ystB^-、yadA^＋、virF^＋），Ⅱ型（ail^＋、ystA^＋、ystB^-、yadA^-、virF^-），Ⅲ型（ail^-、ystA^-、ystB^＋、yadA^-、virF^-），Ⅳ型（ail^-、ystA^-、ystB^-、yadA^-、virF^-）。脉冲场凝胶电泳分析，O：3型菌株显示有2种带型，O：5型菌株的带型完全相同，O：8型菌株的带型则存在明显差异。结论：浙江省的从动物分离的小肠结肠炎耶尔森菌以非致病性菌株居多，且存在一定的地区差异。猪是致病性小肠结肠炎耶尔森菌的重要携带者，应警惕致病性小肠结肠炎耶尔森菌通过猪感染人和其它动物以及环境的危险。     

江苏省南通地区小肠结肠炎耶尔森菌分布特征初步研究

目的了解江苏省南通地区小肠结肠炎耶尔森菌的分布特点和毒力特征。方法用常规方法从家畜家禽粪便标本中分离小肠结肠炎耶尔森菌，PCR法检测其五种毒力相关基因，同时对国内分离到的O：8血清型菌株进行脉冲场凝胶电泳分析。结果从该地区293份家畜家禽粪便标本中分离到91株小肠结肠炎耶尔森菌，分离率为31．06％。未分离到国内主要流行血清型O：3和O：9，其中有39．57％菌株毒力基因分布特征为：ail^-、ystA^-、ystB^-、yadA^-、virF^-，有60．43％菌株为ail^-、ystA^-、ystB^＋、yadA^-、VirF^-，两株国外引进的强毒菌株具有相同的脉冲图形，与国内分离到的O：8血清型菌株存在显著的差异。结论致病性小肠结肠炎耶尔森菌的分布具有局限性，江苏省南通地区小肠结肠炎耶尔森菌的分布可能以非致病菌为主。     

O∶3和O∶9小肠结肠炎耶尔森菌主要毒力基因分布调查

目的　了解我国常见致病性血清型毒力基因的分布情况。方法　参照国外发展成熟的聚合酶链反应(PCR)技术进行毒力基因检测。结果　实验证实在我国分离到的主要流行血清型O∶3和O∶9小肠结肠炎耶尔森菌毒力基因分布特征为 :ail 、ystA 、ystB-、yadA 、virF 占 5 6.2 % ;ail 、ystA 、ystB-、yadA-、virF-占 2 5 .6% ;其他型占18.2 %。结论　通过实验证实在我国引起感染暴发和流行的血清型O∶3和O∶9小肠结肠炎耶尔森菌毒力基因的分布主要为 :ail 、ystA 、yadA 、ystB-、virF 型 ,很少部分的ail 、ystA 、ystB-、yadA-、virF-根据以前的资料被认为是毒力质粒丢失的结果 ,其他型很有可能是非致病的菌株。     

小肠结肠炎耶尔森菌O:9血清型特异性单克隆抗体筛选及其应用

目的利用杂交瘤技术筛选出能分泌小肠结肠炎耶尔森菌O：9血清型特异性单克隆抗体的细胞株,用于该型菌株的鉴定.方法采用ELISA方法筛选克隆株,并用玻片凝集法进行单克隆抗体的特异性鉴定.结果筛选到3株能分泌小肠结肠炎耶尔森菌O：9血清型特异性单克隆抗体的杂交瘤细胞株,分泌的抗体与经鉴定的18株小肠结肠炎耶尔森菌O：9血清型菌株呈阳性反应,而与其他血清型小肠结肠炎耶尔森菌及常见肠道致病菌无交叉凝集反应;应用于小肠结肠炎耶尔森菌野生株分型鉴定时,能准确鉴定出其中的24株O：9血清型菌株,与用日本进口分型血清鉴定、PCR毒力基因检测结果相同.结论筛选获得的细胞株产生的单克隆抗体,用于小肠结肠炎耶尔森菌O：9血清型鉴定,具有很好的型特异性,避免了过去免疫血清制备中繁琐的抗原交叉吸收试验.     

1997-2010年宁夏回族自治区小肠结肠炎耶尔森菌致病性的基因特征

目的 了解宁夏回族自治区小肠结肠炎耶尔森菌主要毒力基因分布情况和致病性小肠结肠炎耶尔森菌分子分型特征。方法 于1997-2010年在宁夏回族自治区共分离得到283株小肠结肠炎耶尔森菌,用PCR法分析其黏附侵袭位点基因(ail)、耐热肠毒素A基因（ystA）、ystB、黏附素基因（yadA）、毒力活化因子基因（virF）;应用限制性内切酶Not Ⅰ酶切致病性小肠结肠炎耶尔森菌染色体DNA进行脉冲场凝胶电泳(PFGE),利用BioNumerics软件进行聚类分析。结果 209株O∶3、O∶9血清型小肠结肠炎耶尔森菌中ail、ystA、yadA、virF毒力基因阳性,ystB为阴性的占97.6％( 204/209);O∶8血清型和未开展血清分型的菌株5种毒力基因全部阴性;11株O∶5血清型有9株5种毒力基因全部阴性。将致病性菌株进行PFGE分型,根据染色体DNA的Not Ⅰ酶切图谱,将29株O∶3血清型分成12个PFGE带型,包含5株以上的优势PFGE带型有2种。180株O∶9血清型菌株分成13个PFGE带型,包含10株以上的优势PFGE带型有4种,各自是从同一地区猪与家鼠、猪与犬、猪与野兔分离。结论 宁夏地区O∶3、O∶9血清型小肠结肠炎耶尔森菌具有致病性,O∶3逐步成为如今的优势血清型;O∶5、O∶8与血清未分型的菌株无致病性。     

小肠结肠炎耶尔森菌O∶9血清型特异性单克隆抗体筛选及其应用

目的利用杂交瘤技术筛选出能分泌小肠结肠炎耶尔森菌O∶9血清型特异性单克隆抗体的细胞株,用于该型菌株的鉴定。方法采用ELISA方法筛选克隆株,并用玻片凝集法进行单克隆抗体的特异性鉴定。结果筛选到3株能分泌小肠结肠炎耶尔森菌O∶9血清型特异性单克隆抗体的杂交瘤细胞株,分泌的抗体与经鉴定的18株小肠结肠炎耶尔森菌O∶9血清型菌株呈阳性反应,而与其他血清型小肠结肠炎耶尔森菌及常见肠道致病菌无交叉凝集反应;应用于小肠结肠炎耶尔森菌野生株分型鉴定时,能准确鉴定出其中的24株O∶9血清型菌株,与用日本进口分型血清鉴定、PCR毒力基因检测结果相同。结论筛选获得的细胞株产生的单克隆抗体,用于小肠结肠炎耶尔森菌O∶9血清型鉴定,具有很好的型特异性,避免了过去免疫血清制备中繁琐的抗原交叉吸收试验。     

广州地区食品中小肠结肠炎耶尔森氏菌分布特性的初步研究

目的：了解广州地区食品中小肠结肠炎耶尔森氏菌的分布特性。方法：采用随机抽样方法分别对广州十区两市日常监测的样品,共计207份,参照国标方法进行小肠结肠炎耶尔森氏菌的检测和鉴定,并对分离菌株的生物分型、血清型分型、毒力基因携带等特征作分析。结果：207份样品中14份检出小肠结肠炎耶尔森氏菌,阳性率为6.22%。分离到O：1,2、O：5、O：8三种血清型的菌株。14株菌株均为非致病的生物1A型,其中8株携带毒力基因ystB,3株携带yadA基因。冬、春季的分离率比夏、秋季的高（χ^2检验,P〈0.005）。结论：本地区食品中存在小肠结肠炎耶尔森氏菌的污染,以非流行株为主。应加强本地区食品加工、流通方面的监督管理,以减少可能引起食源性疾病的因素。     

2006-2010年高密市小肠结肠炎耶尔森菌调查

目的了解高密市食品中小肠结肠炎耶尔森菌及动物带菌情况。方法 2006-2010年采集家畜家禽粪便、冷冻食品共2 097份,4℃冷增菌后用选择性培养基进行病原菌分离培养并作生化鉴定,将可疑菌株做进一步的血清学鉴定和生物分型及毒力检测。结果 2 097份标本中分离出131株小肠结肠炎耶尔森菌,总的检出率为6.25%,其中O∶3(携带毒力基因ail+、ystA+、rbfc+)和O∶9血清型的检出率分别为0.76%和1.52%。108株仅携带ystB基因(82.44%);26株不携带任何基因(19.85%)。131株小肠结肠炎耶尔森菌分布在3个生物型,其中生物1A型占74.80%;生物3型占1.52%;生物4型占0.76%。结论本地区存在致病性小肠结肠炎耶尔森菌,有感染人和动物及引起食源性型疾病的可能,因此必须加大该菌的监测力度,以预防小肠结肠炎耶尔森菌病的感染流行。     

中国六省致病小肠结肠炎耶尔森菌的脉冲场凝胶电泳分析

目的 对中国致病小肠结肠炎耶尔森菌分离株进行脉冲场凝胶电泳分析。方法 参照美国疾病预防控制中心PulseNet实验方法对中国6省165株致病小肠结肠炎耶尔森菌进行脉冲场凝胶电泳分析，使用BioNumerics软件进行聚类分析，并按照PulseNet命名原则对带型进行命名。结果 将114株O：3血清型小肠结肠炎耶尔森菌分成25个带型；K6GNllC30012（50株）、K6GNllC30015（19株）及K6GNllC30016（10株）是其主要带型，三个主要带型之间聚类相似性很高。将51株O：9血清型小肠结肠炎耶尔森菌分为14个带型；其中K6GNllC90004（22株）与K6GNllC90010（13株）是其主要带型，K6GNllC90004与K6GNllC90010带型之间有一定的差异。O：3与O：9血清型的主要带型之间有明显的差异。结论 O：3血清型的小肠结肠炎耶尔森菌可能起源于一个克隆系，且在不同地区和年代变异很小；O：9血清型的小肠结肠炎耶尔森菌可能起源于两个不同的克隆系，且各自有一定的变异。O：3与O：9血清型的小肠结肠炎耶尔森菌亲缘关系较远。     

Antimicrobial resistance of Escherichia coli O26, O103, O111, O128, and O145 from animals and humans

Susceptibilities to fourteen antimicrobial agents important in clinical medicine and agriculture were determined for 752 Escherichia coli isolates of serotypes O26, O103, O111, O128, and O145. Strains of these serotypes may cause urinary tract and enteric infections in humans and have been implicated in infections with Shiga toxin-producing E. coli (STEC). Approximately 50% of the 137 isolates from humans were resistant to ampicillin, sulfamethoxazole, cephalothin, tetracycline, or streptomycin, and approximately 25% were resistant to chloramphenicol, trimethoprim-sulfamethoxazole, or amoxicillin-clavulanic acid. Approximately 50% of the 534 isolates from food animals were resistant to sulfamethoxazole, tetracycline, or streptomycin. Of 195 isolates with STEC-related virulence genes, approximately 40% were resistant to sulfamethoxazole, tetracycline, or streptomycin. Findings from this study suggest antimicrobial resistance is widespread among E. coli O26, O103, O111, O128, and O145 inhabiting humans and food animals.     

大肠杆菌O157:H7的分离筛选与实验诊断

O157:H7菌株是新近认识的肠出血性大肠杆菌(EHEC)的主要菌株.自1982年首次在美国发现以来,全球许多国家相继发生该菌感染及暴发流行,成为新的凶险传染病之一.国内自1987年首次分离到O157:H7以来,许多地方已发现该菌株.     

Distribution and virulence of Vibrio cholerae belonging to serogroups other than O1 and O139: a nationwide survey.

The distribution and virulence of Vibrio cholerae serogroups other than O1 and O139 in India before, during and after the advent of O139 serogroup was investigated. A total of 68 strains belonging to 31 different ''O'' serogroups were identified during the study period. With the exception of O53, there was no spatial or temporal clustering of any particular non-O1 non-O139 serogroup at any given place. Two of the 68 strains examined produced cholera toxin (CT) which could only be partially absorbed with anti-CT immunoglobulin G. Tissue culture assay revealed that some of the non-O1 non-O139 strains produced factors which evoked either a cell rounding or cell elongation response depending upon the medium used. This study indicates that serogroups other than O1 and O139 should also be continuously monitored.     

Detection of Shiga toxin-producing Escherichia coli O26, O45, O103, O111, O113, O121, O145, and O157 serogroups by multiplex polymerase chain reaction of the wzx gene of the O-antigen gene cluster

O-antigens on the surface of Escherichia coli are important virulence factors that are targets of both the innate and adaptive immune system and play a major role in pathogenicity. O-antigens that are responsible for antigenic specificity of the strain determine the O-serogroup. E. coli O26, O45, O103, O111, O113, O121, O145, and O157 have been the most commonly identified O-serogroups associated with Shiga toxin-producing E. coli (STEC) implicated in outbreaks of human illness all over the world. A multiplex polymerase chain reaction assay was developed to simultaneously detect the eight STEC O-serogroups targeting the wzx (O-antigen-flippase) genes of all O-antigen gene clusters. The sensitivity of the multiplex polymerase chain reaction was found to be 10 colony forming units for each O-group when enriched in broth and 100 colony forming units when enriched in artificially inoculated apple juice diluted with tryptic soy broth for 16?h at 37°C. The method can be used for detecting STEC O-groups simultaneously and may be exploited for improving the safety of food products.     

Detection by multiplex real-time polymerase chain reaction assays and isolation of Shiga toxin-producing Escherichia coli serogroups O26, O45, O103, O111, O121, and O145 in ground beef

Six Shiga toxin-producing Escherichia coli (STEC) serogroups, which include O26, O45, O103, O111, O121, and O145, are responsible for the majority of non-O157 STEC infections in the United States, representing a growing public health concern. Cattle and other ruminants are reservoirs for these pathogens; thus, food of bovine origin may be a vehicle for infection with non-O157 STEC. Methods for detection of these pathogens in animal reservoirs and in food are needed to determine their prevalence and to develop intervention strategies. This study describes a method for detection of non-O157 STEC in ground beef, consisting of enrichment in modified tryptic soy broth at 42°C, followed by real-time multiplex polymerase chain reaction (PCR) assays targeting stx(1), stx(2), and genes in the O-antigen gene clusters of the six serogroups, [corrected] and then immunomagnetic separation (IMS) followed by plating onto Rainbow? Agar O157 and PCR assays for confirmation of isolates. All ground beef samples artificially inoculated with 1-2 and 10-20 CFU/25?g of ground beef consistently gave positive results for all of the target genes, including the internal amplification control using the multiplex real-time PCR assays after enrichment in modified tryptic soy broth for a total of 24?h (6?h at 37°C and 18?h at 42°C). The detection limit of the real-time multiplex PCR assays was ～50 CFU per PCR. IMS for O26, O103, O111, and O145 was performed with commercially available magnetic beads, and the IMS beads for O45 and O121 were prepared using polyclonal antiserum against these serogroups. A large percentage of the presumptive colonies of each serogroup picked from Rainbow Agar O157 were confirmed as the respective serogroups; however, the percent recovery of STEC O111 was somewhat lower than that of the other serogroups. This work provides a method for detection and isolation in ground beef and potentially other foods of non-O157 STEC of major public health concern.     

Hemoglobin O Arab: about 20 cases

BACKGROUND: Hemoglobin O Arab is a rare abnormal hemoglobin. AIM: We report the Clinical and biological features of this disease METHODS: 20 patients.:16 were compound hétérozygous Hb O Arab/Béta thalassemia and 4 homozygous Hemoglobin O Arab. Patients are 7 men and 13 women. RESULTS: Most of them are originated from the North West of Tunisia with a age average of 39.7 years. Diagnosis was carried out at a relatively old age (26.9 years old). The homozygous form was not very symptomatic. The compound heterozygous form was more severe and characterized by a mild form of thalassemia with a moderate microcytic hypochromic anaemia (Hb = 8.8 g/dl). It was often complicated of thrombopenia due to hypersplenism in 40% of the cases. Treatment was based on occasionally transfusion and splenectomy on event of hypersplenism. Evolution of this disease was generally good with a long lifespan of patients. CONCLUSION: Haemoglobin O Arab is an abnormal hemoglobin well tolerated except for heterozygous category which requires iterative transfusions. Spelenectomy is indicated in case of hypersplenious. The evolution is generally good with a long survival.