病绵羊体内分离的拟似绵羊附睾种布氏菌的首次系统鉴定与分类

我们对新疆地方病防治研究所近年来从患附睾炎的公绵羊精液中分离出１５株拟似布氏菌，除按常规检定外，还采用了Ｓ群及Ｒ群噬菌体裂解试验、绵羊附睾种血清的试管凝集反应，并对有的菌株做了ＤＮＡ Ｇ＋Ｃｍｏｌ％含量测定，最后判定：在这十五株菌中有７株为绵羊附睾种布氏菌。     

子宫及配种攻毒布鲁氏菌后S2苗对怀孕母猪的保护力试验

本文报道了用临床学、细菌学、血清学及病理组织学方法研究了通过子宫及配种途径攻毒布氏苗后S_2苗对孕猪的保护力,结果表明当用10~6强毒攻毒后,其实际综合保护力可达70.24％。本研究为用菌苗防制猪布病打下了基础。     

Epidemiology and management of a bovine brucellosis cluster in Northern Ireland

An epidemiological investigation was undertaken of 41 bovine brucellosis outbreaks that occurred within a 10-month period, in a region where eradication measures appeared to be succeeding. The primary outbreak comprised three herds with significant within-herd spread and a high probability of multiple abortions. Direct contact between cattle at pasture was the most likely means of between-herd transmission for most (71%) outbreaks, with an attack rate of 28.1% in herds immediately neighbouring the primary outbreak herds and 11.3% in the next concentric ring of farms. Resolution of the incident was attributed to a rapid response by the veterinary authorities, detailed epidemiological investigations, repeated, prolonged testing of contact herds and employment of parallel testing.     

Brucella canis in a HIV-infected patient

The true incidence of Brucella canis in humans is unknown, but immunocompromised patients in direct contact with dogs are thought to be at a higher risk for infection. In this case report, we present a human case of B. canis in a patient infected with human immunodeficiency virus.     

Comparison of agar gel immunodiffusion test, rapid slide agglutination test, microbiological culture and PCR for the diagnosis of canine brucellosis

The performance of the rapid slide agglutination test, with and without 2-mercaptoethanol (RSAT and 2ME-RSAT) and agar gel immunodiffusion test (AGID) was evaluated for the diagnosis of brucellosis in naturally infected dogs. The microbiological culture, PCR and clinical parameters were used as reference. A total of 167 dogs were clinically examined and tested by blood culture, culture of semen/vaginal swab and PCR in blood and semen/vaginal swab. According to the results observed the 167 dogs were divided into three groups: Brucella canis infected dogs (Group 1), B. canis non-infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The dogs were then tested by RSAT, 2ME-RSAT and AGID. Groups 1 and 2 were used to calculate the diagnostic sensitivity and specificity of the serological tests and the results observed in Group 3 were also discussed. The diagnostic sensitivity of RSAT, 2ME-RSAT and AGID was respectively 70.58%, 31.76%, and 52.94%. The diagnostic specificity of RSAT, 2ME-RSAT and AGID was respectively 83.34%, 100%, and 100%. In dogs with suspected brucellosis 15% were RSAT positive, none was 2ME-RSAT positive and 5% were AGID positive. Although the serological tests are the most commonly used methods for brucellosis diagnosis, a significant proportion of false-negative results were observed highlighting the importance of the direct methods of diagnosis, like blood culture and PCR to improve the diagnosis of canine brucellosis.     

羊种布鲁氏菌wzt基因的原核表达及间接ELISA方法的建立

为建立检测血清中布鲁氏菌抗体的间接ELISA方法,本试验采用PCR技术从羊种布鲁氏菌QY1菌株中扩增得到wzt基因片段,连接到pET-30a载体上,构建质粒pET-30a-wzt,将鉴定正确的质粒转化E.coli BL21（DE3）感受态细胞,经原核表达系统对其进行表达,表达产物用SDS-PAGE和Western blotting进行分析后,用亲和层析镍柱纯化wzt重组蛋白备用。以wzt重组蛋白为检测抗原,逐步优化条件后建立布鲁氏菌间接ELISA检测方法。结果显示,试验成功构建了pET-30a-wzt原核表达载体,并在BL21（DE3）宿主菌中表达;SDS-PAGE和Western blotting结果表明,重组蛋白约为35 ku,表达形式为上清,条带单一、无杂带,有很好的反应原性和特异性。ELISA优化试验确定了最佳包被浓度为15 μg/mL,血清最佳稀释度为1：80,酶标抗体的最佳稀释度为1：5 000;通过检测24份阴性样品确定临界值,当样品D_{450 nm}值≥ 0.30为阳性,样品D_{450 nm}值<0.30时为阴性;特异性试验表明,该方法不与小肠耶尔森菌、大肠杆菌发生交叉反应;批内及批间变异系数均<10%;用该方法对120份血清样本进行检测,并与虎红凝集试验进行相符性验证,符合率为96%。本试验建立的间接ELISA方法为布鲁氏菌病的检测提供了可靠的技术手段。     

一种检测奶样中布鲁氏菌抗体免疫层析方法的建立

通过制备脂多糖(LPS)并将其作为检测抗原,建立了一种检测奶样中布鲁氏菌抗体的酶联免疫层析方法。通过对处理方法和反应条件的优化,制备出敏感性高、特异性强的布鲁氏菌抗体检测试纸条。该试纸条敏感性为98.0%,抗体滴度为1:2~1:8,特异性为96.0%,且与其他常见病原无交叉反应,批内、批间重复性良好。保存期加速试验显示,该试纸条在2~30℃下可保存12个月;符合率验证显示,该方法与标准奶样的符合率达94.9%。上述结果表明,该检测方法具有敏感性高、特异性强以及方便、快捷等优点,适用于现场大批量检测,因而可应用于奶牛场布鲁氏菌病的快速诊断。     

布鲁菌Ⅳ型分泌系统效应蛋白DK63-887基因缺失株的构建及鉴定

为了构建羊布鲁菌16M(简称16M)的DK63-887基因缺失株(16MΔDK63-887),探讨该基因与16M介导自噬的关系。利用同源重组和抗性替换的方法,以卡那基因替换DK63-887基因,获得突变株16MΔDK63-887。将亲本株16M、疫苗株M5-90、突变株16MΔDK63-887在相同条件下振荡培养,观察其生长趋势变化;将各菌株置于不同外界环境中,观察其生存率;将各菌株侵染小鼠巨噬细胞,比较它们在宿主细胞内的生存能力及RT-qPCR检测自噬相关基因的表达。成功获得了布鲁菌DK63-887基因缺失株且在20代内未发生回复性突变现象。与亲本株相比,16MΔDK63-887在体外培养生长趋势与亲本株相似,只是细菌的浓度存在一定差异;突变株在外界应激条件下生存能力低于亲本株;侵染4h后缺失株胞内细菌数量明显下降;RT-qPCR检测到突变株的ULKI、Beclin1表达量均显著降低(P0.01),结果表明,布鲁菌Ⅳ型分泌系统效应蛋白与16M介导的细胞自噬密切相关,为16M胞内寄生机制的研究奠定了基础。     

Risk factors for brucellosis seroprevalence of sheep and goat flocks in Spain

Risk factors for ovine and caprine brucellosis in the Ávila region (center of Spain) were evaluated using data from a cross-sectional study of the most important diseases of small ruminants in this Spanish region between 1996 and 1997. Questionnaire data from 56 herds (35 ovine and 21 caprine) were used. Sixteen (29%) flocks (3 caprine and 13 ovine) were brucellosis-seropositive. Overall, 0.7% of sheep and 0.1% of goats were seropositive. Eleven risk factors were studied at the group level by logistic regression using flock brucellosis-status as outcome, and by linear regression using percentage of brucellosis-seropositivity as outcome. Both final models contained the same variables: contact with sheep and grazing in communal pastures as risk factors, and frequency of disinfecting practices as a protective factor.     

左旋咪唑对鸡细胞免疫和体液免疫功能的作用

系统研究了左旋咪唑对鸡细胞免疫和体液免疫功能的作用。结果表明左旋咪唑可影响正常鸡的免疫功能 :左旋咪唑可显著促进鸡外周血T淋巴细胞增殖 ,但对B淋巴细胞无明显影响 :2 5～ 1 0mg/kg左旋咪唑可使CD+4/CD+8淋巴细胞比值明显升高 ;左旋咪唑可使鸡体内抗颗粒性、胸腺依赖性抗原SRBC抗体滴度 ,抗可溶性、胸腺依赖性抗原BSA抗体滴度和抗非胸腺依赖性抗原BA抗体滴度均明显升高 ;2 5～ 1 0mg/kg左旋咪唑可使鸡血清总补体活性明显升高。左旋咪唑影响正常鸡回忆性免疫应答反应 :左旋咪唑 ( 1 0mg/kg)可使二次免疫鸡抗SRBC抗体滴度和抗BA抗体滴度回忆性免疫应答反应明显升高 ;但使鸡对抗BSA抗体滴度回忆性免疫应答反应明显降低。