采用PCR方法对我国蜱伯氏疏螺旋体感染的流行病学调查

通过调查我国已有的4种蜱伯氏疏螺旋体的感染情况,以进一步阐明莱姆病在中国的分布与流行状况。本研究通过筛选扩增伯氏疏螺旋体外膜蛋白A(OspA)基因片段的通用引物,获得1对特异性引物,优化反应条件后建立用于检测蜱体内伯氏疏螺旋体的PCR方法,其扩增片段大小为307 bp。该方法可检测出10 pg的阿氏疏螺旋体(Ba)、1 pg的伽氏疏螺旋体(Bg)和0.01 pg的狭义伯氏疏螺旋体(Bb)的3种不同基因型的伯氏疏螺旋体的OspA基因组DNA,表明其敏感性较好,适用于蜱感染伯氏疏螺旋体状况的调查。本研究从我国7个省采集到的667只蜱,进行伯氏疏螺旋体感染的流行病学调查,分类鉴定表明这些蜱分属革蜱属、血蜱属、牛蜱属和扇头蜱属。PCR检测所获数据表明它们的感染率分别为4%(10/264)、6%(11/137)、31.4%(59/185)和31%     

新的人畜共患病——莱姆病及其新种病原体——波氏疏螺旋体

<正> 瑞典医生Arvid Afzelius报告了慢性游走性红斑(Erythema chronicum migrans)病(Acta Derm.Venereol.,1921,2:120～125),病在蜱叮咬之后发生。以后,欧洲续有此病报导,证明蓖子硬蜱是疾     

含伯氏疏螺旋体OspA、OspC蛋白VLPs的构建及鉴定

莱姆病是一种经蜱传播的人兽共患病,随着人们经济的发展,伴侣动物的不断出现增加了人与动物经蜱传播莱姆病的风险,而当前并未有治疗莱姆病的有效方法,因此研制莱姆病疫苗成为一大热点。为了更好地预防莱姆病的发生,本研究通过替换新城疫病毒血凝素-神经氨酸酶蛋白(haemagglutinin-neuraminidase protein,HN)胞外域的方式,利用昆虫杆状病毒表达系统分别构建了含伯氏疏螺旋体候选抗原表位外膜蛋白A(outer surface protein A,OspA)、外膜蛋白C(outer surface protein C,OspC)的新城疫病毒样颗粒(virus-like particles,VLPs),形成了含有伯氏疏螺旋体抗原表位的新城疫病毒样颗粒,为之后研制莱姆病疫苗提供了新思路、新想法。     

蜱传性疾病--莱姆病螺旋体研究进展

莱姆病是一种蜱传性人兽共患病,在我国北方各省广泛流行,其病原体为伯氏疏螺旋体。莱姆病可使皮肤、心脏、关节和神经系统等多种组织器官受损。本文综述了莱姆病螺旋体的形态、种下分类、生化特征、传播媒介和贮存宿主等方面的研究进展"     

吉林省四平市周边地区莱姆病流行情况调查及优势菌株外膜蛋白C的表达

为了解吉林省四平市周边地区伯氏疏螺旋体流行情况,本试验于2017年5-7月分别采集四平市周边地区蜱虫样品共25份。通过筛选扩增伯氏疏螺旋体外膜蛋白C(OspC)基因片段的通用引物、优化反应条件后建立用于检测蜱体内伯氏疏螺旋体的PCR方法。从25份样品中分离到8份阳性样品(阳性率约为32%),经过测序比对发现其基因型均为Borrelia burgdorferi;并以分离到的Borrelia burgdorferi DNA为模板,PCR扩增OspC基因,构建重组质粒pET-30a-OspC,以IPTG诱导蛋白表达,为建立伯氏疏螺旋体ELISA检测方法奠定了基础。     

伯氏疏螺旋体鞭毛基因的克隆及序列分析

根据已有的伯氏疏螺旋体鞭毛基因序列,设计两条特异性引物,PCR扩增该基因,并获得基因全长序列,大小为1 008 bp。采用生物信息学技术,对所获得的伯氏疏螺旋体鞭毛基因序列和拟编码的蛋白序列进行分析,发现其编码336个氨基酸,编码蛋白的理论分子量为35.7 ku,等电点为5.53,具有多个抗原表位序列,其中编码主要抗原位点的片段位于中央区段,该中央区段还具有伯氏疏螺旋体种的保守性。伯氏疏螺旋体鞭毛基因中央区段编码蛋白既是主要的抗原位点又具有保守性,理论上可作为莱姆病的诊断抗原。本文为莱姆病的实验室诊断奠定基础。     

荧光定量PCR检测硬蜱体内莱姆病螺旋体的研究

为建立一个荧光定量PCR检测硬蜱体内莱姆病螺旋体的方法,根据GenBank登录的莱姆病螺旋体鞭毛蛋白FlaB序列,应用生物学软件进行序列比对,在保守的C段区设计与筛选特异引物和TaqMan探针。对荧光定量PCR反应体系与条件进行优化,验证方法的特异性、敏感性,并通过对感染螺旋体的蜱样本的检测,评价该方法的实用价值。结果显示,自然感染莱姆病螺旋体的35份蜱标本检测阳性符合率100%,正常蜱20份标本的检测结果均为阴性。该方法对牛巴贝斯原虫、泰勒原虫、边缘无浆体、金龟子绿僵菌、大肠杆菌等蜱体常见病原微生物所抽提的DNA的检测均呈阴性。荧光定量PCR方法检测质粒的灵敏度可达1×102拷贝/μL。TaqMan荧光定量PCR方法检测硬蜱体内莱姆病螺旋体具有较好的敏感性和特异性,可适于莱姆病的流行病学调查和监控。     

莱姆病螺旋体感染对蜱的4个功能基因的转录影响

为探索蜱及蜱传病的防控新策略,了解病原与媒介硬蜱相互作用的分子机制,本研究以莱姆病病原伯氏疏螺旋体感染后对长角血蜱4个功能基因的转录影响进行了研究。将不同浓度梯度的伯氏疏螺旋体显微注射到长角血蜱体内,分不同的时间段提取蜱的总RNA,反转录成cDNA后,用实时荧光定量PCR检测蜱基因的表达水平。结果显示:伯氏疏螺旋体感染对蜱半胱氨酸蛋白酶抑制剂1(HLcyst-1)、半胱氨酸蛋白酶抑制剂3(HLcyst-3)、卵泡抑素(FRP)、凝血酶抑制剂(Hemalin)4个功能基因的转录均产生了显著影响,但存在时间和剂量相关性,感染后第4天显著诱导了长角血蜱HLcyst-1基因的表达,抑制了Hemalin基因表达。     

新疆部分地区梅迪维斯纳病毒感染的血清学调查

旨在了解新疆地区梅迪维斯纳病的流行现状和特点，本研究于2017—2019年从新疆阿克苏、阿勒泰、巴州、昌吉、哈密、石河子和伊宁收集2 647份羊血清样品，采用酶联免疫吸附试验（ELISA）进行梅迪维斯纳病抗体检测，对不同地区、品种、性别来源绵羊的梅迪维斯纳病抗体阳性率进行统计分析。结果显示，阿克苏、阿勒泰、巴州、昌吉、哈密、石河子和伊宁梅迪维斯纳病抗体阳性率分别为28.95%（121/418）、0.67%（5/751）、2.50%（2/80）、4.91%（8/163）、1.14%（3/264）、1.22%（1/82）和17.10%（152/889）；其中，阿勒泰羊、和田羊、哈萨克羊、美利奴羊、萨福克羊、小尾寒羊的梅迪维斯纳病抗体阳性率分别为0.35%（1/288）、1.14%（3/264）、22.87%（231/1 010）、13.86%（42/303）、1.85%（13/702）和2.50%（2/80）；新疆本土品种羊与引进品种羊血清梅迪维斯纳病抗体阳性率分别为0.79%（8/1 015）、1.58%（15/947）；公羊与母羊梅迪维斯纳病抗体阳性率分别为3.59%（34/946）、15.17%（258/1 701）。本研究结果分析表明，需要对梅迪维斯纳病进行早期检疫，及时发现并淘汰病羊，改善饲养管理条件，这对促进羊产业健康发展具有重要意义。     

新疆部分地区马疱疹病毒1型感染的血清学调查

旨在了解新疆地区马疱疹病毒1型感染的流行现状和特点,本研究于2019-2020年从新疆乌鲁木齐、昌吉州、伊犁州、巴州16处规模化马场收集1 657份马血清样品,采用酶联免疫吸附试验(ELISA)进行抗体检测,对不同地区、品种、性别及年龄马匹的马疱疹病毒1型抗体阳性率进行统计分析.结果显示,乌鲁木齐、伊犁州、昌吉州、巴州...     

Arthritis caused by Borrelia burgdorferi in dogs

From October 1982 to May 1984, we studied 34 dogs from the Lyme, Conn area that had a history of tick exposure and lameness associated with pain, warmth, and/or swelling in one or more joints. Large numbers of polymorphonuclear leukocytes were seen in Giemsa-stained smears of synovial fluid from 9 dogs, and spirochetes (Borrelia burgdorferi) were found in 1 sample by darkfield microscopy and immunoperoxidase techniques. The geometric mean antibody titer to B burgdorferi in the 34 dogs was 1:2,700, compared with 1:285 in 43 clinically normal dogs from the same area (P less than 0.0001) and 1:50 in 29 dogs from an area in New Jersey that is not endemic for human Lyme disease (P less than 0.00001). We concluded that B burgdorferi in dogs may cause arthritis similar to that in human Lyme disease.     

Borrelia burgdorferi infection in cats in the UK

Using an enzyme-linked immunosorbent assay (ELISA) and Western blotting techniques, cats from the north west of England and North Wales were tested for antibodies to Borrelia burgdorferi. Seropositivity to B burgdorferi in these cats was similar (4.8 per cent) to that found in dogs and horses in the UK from non-endemic areas. Cross-reactive antibodies to Leptospira interrogans serovars did not affect the cat B burgdorferi ELISA data. Clinical signs of Lyme disease were generally absent; lameness was rarely reported. As in other species, it must be considered that high levels of serum anti-borrelia antibodies are not diagnostic for clinical Lyme disease.     

我国部分地区Sicinivirus流行病学调查

Sicinivirus是一种禽类新发病毒,可引起家禽发育迟缓综合症、腹泻、吸收不良综合征等.目前,仅部分国家开展了该病毒的流行病学调查,研究数据极为有限.为明确该病毒在我国的流行情况,以及该病毒感染率与地域、宿主、养殖方式之间的关系,2019年下半年在江苏、广西、河北、安徽、广东、上海、湖北和江西8个省(自治区、直辖市...     

Serologic cross-reactivity of antibodies against Borrelia theileri, Borrelia burgdorferi, and Borrelia coriaceae in cattle.

OBJECTIVE: To evaluate the immune response induced by Borrelia theileri infection and to determine whether B theileri induces cross-reacting antibodies to other bovine borreliae. ANIMALS: Two 3-month-old calves, 1 of which was splenectomized. PROCEDURE: Calves were exposed to Boophilus microplus infected with B theileri. Rectal temperature, PCV, bacteremia, and clinical signs of infection were monitored. Serum was obtained weekly and used to evaluate the humoral response to homologous antigen and B burgdorferi and B coriaceae, using an indirect fluorescent antibody (IFA) test, and to B burgdorferi, using a commercially available ELISA. The identity of cross-reacting antigens was explored, using monoclonal antibodies to genus- and species-specific antigens in an IFA test. RESULTS: B theileri-infected calves produced antibodies that cross-reacted with B burgdorferi and B coriaceae whole-cell antigens. Borrelia theileri whole-cell antigen was recognized by genus-specific monoclonal antibody H9724 but not by species-specific antibody H5332. False-positive reactions were not observed when serum from B theileri-infected calves was tested by use of the ELISA for B burgdorferi. CONCLUSIONS: B theileri induces humoral responses in infected cattle that can be confused with those of other borrelial infections. Care must be taken to definitively distinguish between the various borreliae that may cause disease in cattle. CLINICAL RELEVANCE: Serologic cross-reactivity must be taken into account when making a serodiagnosis of Lyme borreliosis or epizootic abortion in epidemiologic studies involving cattle.     

Antibodies to Borrelia burgdorferi in dogs in North Carolina

An indirect immunofluorescence assay was used to detect antibodies against Borrelia burgdorferi in sera from 600 dogs in 1983 and 402 dogs in 1985. In 1983, the overall prevalence rate of dogs with B burgdorferi titers greater than or equal to 1:64 was 3.6%, whereas in 1985, the prevalence rate was 2.7%. An unexplainable higher seroprevalence was detected in 1 group of dogs tested in 1983. These dogs were from the southern coastal plains of North Carolina. In the dogs tested in 1985, this regional difference in sero-prevalence was not noticed. Statistical differences were not noticed (P greater than 0.05) between dogs from 2 sources or when gender was considered. Seemingly, the prevalence of anti-B burgdorferi antibodies in dogs in North Carolina was low.     

Behavioural Studies on Some Rhodesian Rodents

Field studies (Lake Kariba shoreline and Salisbury) and experiments with a captive colony of 12 species of Rhodesian rodents were undertaken for a period of three years. Comparative behavioural data are presented here with special reference to den and nest behaviour, group and territorial behaviour, reproductive and juvenile behaviour, and activity pattern. No species was found to be truly gregarious except Dendromus mesomelas, but Praomys (Mastomys) natalensis, Lemniscomys griselda, Tatera leucogaster, and Aethomys chrysophilus were found to tolerate crowded conditions in captivity. Nipple dragging of young was found in both species of Aethomys and in Acomys, with the remainder observed to utilise mouth carrying behaviour. It was noted that especially in Rhabdomys and Praomys (Mastomysj, and also in Lemniscomys, young have a strong tendency to scatter in all directions from a disturbed nest, even before their eyes open. The significance of nipple dragging, scattering and crowding behaviour and correlation to survival and tendency to irrupt are discussed. All species were found to be nocturnal (usually with irregular sub cycles of activity) except Rhabdomys (largely diurnal), Lemniscomys (diurnal/crepuscular) and Otomys (nocturnal/crepuscular).     

2020年北疆部分地区猪伪狂犬病毒gE蛋白抗体ELISA检测与分析

为了解2020年1—12月北疆部分地区猪伪狂犬病野毒株(PRV-gE)感染情况,采用间接酶联免疫吸附试验(ELISA)法对从北疆4个地区采集的657份猪血样进行PRV-gE蛋白抗体水平检测.结果显示,4个地区PRV-gE抗体阳性率为29.83％(196/657),乌苏地区与其他地区的抗体水平存在一定差异(P<0.05)...