ICR小鼠自然感染小鼠肝炎病毒后的抗原抗体变化

【摘要】 目的 了解小鼠肝炎病毒(MHV)污染的设施内,ICR小鼠自然感染后MHV抗原抗体存在情况。方法 选择50只ICR小鼠,通过更换“脏垫料”的方式进行饲养,分别在实验第2,4,8,14,21,28,35,42,56和84天各剖杀动物5只,采集血清、盲肠内容物、粪便、肝脏以及肺脏检测抗原抗体分布情况。结果 实验开始第2天,肺脏中检出小鼠肝炎病毒,检出率为20%（1/5）,第4天开始,肝脏、肺部、盲肠以及粪便中均可检出小鼠肝炎病毒; 84天后,肺脏、盲肠、粪便和肝脏阳性检出率降为0。实验第8天,血清中抗体检出阳性,阳性率为100%（5/5）,直至第84天实验结束,抗体阳性率仍维持在100%（5/5）。结论 血清学方法可作为日常监督主要诊断方法,而抗原检测方法只能应用于早期诊断。 【关键词】小鼠肝炎病毒 自然感染 抗原抗体     

Chloramphenicol-resistant Salmonella typhi in Saigon.

Chloramphenicol-resistant Salmonella typhi was detected in Saigon in September 1971. Subsequently, 163 strains of S typhi were isolated, 46 percent of which were resistant to choramphenicol by the agar-disk method. Sixty-two strains were studied by the broth-dilution method; 37 percent had minimal inhibitory concentrations for chloramphenicol greater than 250mug/ml, but all strains were susceptible to 0.4mug/ml of ampicillin and to a disk of a combination of trimethoprim and sulfamethoxazole (Bactrim). Persons infected with chloramphenicol-resistant strains of S typhi responded poorly to chloramphenicol alone, but ampicillin or the combination drug was effective.     

Mechanism of multiresistant Salmonella typhi]

From November 1988 to June 1989, 142 strains of S. typhi were isolated from patients of typhoid fever in Qingpu County, Shanghai These strains were highly sensitive to ceftazidime, ceftriaxone, ofloxacin and enoxacin, the sensitive rates to chloramphenicol, co-trimoxazole and ampicillin being from 67% to 83%. Of these 142 strains, twenty-two were multiresistant strains, being resistant to chloramphenicol, co-trimoxazole, ampicillin, cefazolin, gentamicin, piperacillin and tetracycline. Beta-lactamase production was the possible mechanism of resistance of S.typhi to beta-lactam antibiotics. Plasmid analysis by agarose gel electrophoresis showed that a plasmid band of 98Md was found in all multiresistant strains as well as the conjugates, while in sensitive strains, no plasmid band was found. The 98Md large plasmid seemed to be closely related to the multiresistance of S.typhi. Phage typing of S.typhi strains in Qingpu area revealed that M1 was the most prevalent type and A, E1, D2 etc followed in order of frequency. M1 type seemed to be closely related to the resistance to chloramphenicol, co-trimoxazole and ampicillin.     

2005-2009年贵州省伤寒和副伤寒沙门菌耐药性分析

目的分析贵州省伤寒和甲型副伤寒沙门菌的耐药状况,为临床用药及防控提供依据。方法采用改良K-B法对伤寒、甲型副伤寒沙门菌株进行药物敏感试验。结果贵州省9个市(州、地)26个县(区)的113株伤寒沙门菌和518株甲型副伤寒沙门菌对10种抗生素进行药物敏感性测定。其中伤寒沙门菌除对C IP不耐药,对其余9种抗生素均有不同程度的耐药,甲副沙门菌仅对CFT、NAL、SMZ有不同程度耐药,耐药率达0.88%~95.95%,个别地区出现了对第三代头孢类药的多重耐药株。结论贵州省伤寒、甲副沙门菌耐药情况已较为严重,尤其是多重耐药菌可能会造成伤寒和甲型副伤寒的流行或暴发。加强耐药性监测,指导临床合理用药,对预防控制伤寒和甲型副伤寒具有重要意义。     

伤寒沙门菌PFGE分子分型及耐药性研究

目的对深圳市2004-2011年伤寒沙门菌进行脉冲场凝胶电泳(PFGE)分子分型及耐药性分析,为临床用药和追踪传染源提供依据。方法采用K-B法对42株伤寒沙门菌进行20种抗菌药物敏感性测试,并用PFGE对其进行分子分型。结果 42株伤寒沙门菌株对氨苄西林、阿莫西林/克拉维酸、氨苄西林/舒巴坦、头孢噻吩、头孢他啶、头孢曲松、头孢吡肟、头孢西丁、阿米卡星、庆大霉素、卡那霉素、环丙沙星、左旋氧氟沙星、复方新诺明、甲氧苄啶、氯霉素和四环素17种药物的敏感率均超过90%,对萘啶酸耐药率最高达61.5%。42株伤寒沙门菌株可分为SZ0001-SZ0028共28个PFGE型别,其中流行优势型为SZ0023型别。结论结合药物敏感试验结果和PFGE分子分型结果可以判断伤寒疫情的优势株型。     

湖州地区伤寒杆菌耐药性监测及噬菌体分型

目的 了解湖州地区伤寒杆菌对抗菌药物的耐药状况、噬菌体型别分布及对β－内酰胺类抗生素的耐药机制。方法 对１９８７～１９９９年湖州市中心医院和湖州市防疫站分离的７６６株伤寒杆菌进行了耐药性监测，对１９８７～１９８８年（３３株）和１９９８～１９９９年（４３株）伤寒杆菌进行噬菌体分型及对１９９９年３０株伤寒杆菌进行超广谱β－内酰胺酶检测。结果 湖州地区１９９８～１９９９年与１９８７～１９８８年流行的伤寒杆菌噬菌体型别大体相同，主要为Ｍ１、Ａ、Ｅ１、Ｄ１、Ｄ７型；但Ｍ１型菌析出率明显下降（χ＾２＝５．２０，Ｐ〈０．０５），并出现两种新的型别（Ｄ９型及Ｍ４型）。伤寒杆菌对氯霉素的敏感率从１９９０年起已恢复至９０％以上，但新近发现的５株多重耐药伤寒杆蓖对包括第三代头孢菌素在内的多种抗菌药物均有不同程度的耐药，均为Ｍ１型菌株     

Salmonella typhi in a child with urinary tract infection and urolithiasis

Salmonella species are a rare cause of urinary tract infections in children. They have been associated with a higher incidence of structural abnormalities or immunosuppressive status. We report the case of an 11-year-old girl with urinary tract infection (UTI) secondary to Salmonella typhi and associated with urolithiasis. A review of the subject is then discussed.     

Brodie's abscess of the ulna caused by Salmonella typhi

Osteomyelitis caused by Salmonella typhi is rare in patients with no haemoglobinopathies or other diseases causing immunosuppression. Brodie's abscess is a special variety of subacute or chronic osteomyelitis. An otherwise healthy woman who presented with forearm swelling for 6 months was diagnosed with a Brodie's abscess of the ulna caused by Salmonella typhi. Magnetic resonance imaging and a computed tomography-guided needle biopsy were performed. She was later found to be a Salmonella carrier. The Brodie's abscess was treated by surgical debridement and a course of antibiotics. The clinical, radiological, and management aspects of the disease are discussed.     

Enrichment-ELISA for detection of Salmonella typhi from food and water samples

Objective Development of monoclonal antibody based sandwich enzyme linked immunosorbant assay （sELISA） for rapid detection of Salmonella enterica serovar typhi （S. typhi） from food and water samples and optimization of enrichment procedures for use with the developed sELISA to increase the detection sensitivity of the assay. Methods Spleen cells from BALB/c mice immunized with flagellin （H=d） antigen of S. typhi were fused with Sp2/0 myeloma cells. The hybridoma cell line specific to H=d antigen was established, characterized and ascites raised against one of these clones. The hyperimmune serum to flagellin antigen was raised in New Zealand White rabbits. An sELISA was developed using polyclonal antibody as capture and monoclonal antibody as detection antibody. To design the efficient culture strategies for use with the sELISA, different pre-enrichment and enrichment broths were evaluated. The media included buffered peptone water （BPW） and brain heart infusion broth for pre-enrichment and selenite F broth and Rappaport-Vassiliadis broth as enrichment broths. The developed sELISA with preceding enrichment step in BPW （Enrichment-ELISA） was evaluated in various food samples artificially inoculated with S. typhi bacteria. Various food （30） and water （35） samples collected from field were also tested by Enrichment-ELISA and culture method. Results Out of four specific clones to H=d antigen, one clone （# 2/56, IgG2a isotype） was used in sELISA. The sELISA had the detection limit of 10^4-10^5 cfu of S. typhi. Of the various broths used with sELISA, BPW was found to yield maximum ELISA values. Enrichment-ELISA, when tested in artificially inoculated food samples, generally, could detect 10^2 S. typhi cfu/mL within 10 h from various food rinses （meat, vegetable） and milk samples. After overnight enrichment in BPW, as less as 2 bacteria per 10 mL of milk, meat rinse, and chicken rinse could be detected. Only one of the field samples （water） gave false positive result by Enrichment-     

16例婴幼儿伤寒生化结果分析

目的分析16例婴幼儿伤寒生化结果,为临床诊疗提供参考依据。方法对16例伤寒婴幼患儿的生化结果,包括肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBD)、门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT),γ-L-谷氨转肽酶(GGT)、尿素氮(BUN)、肌酐(Cr)、尿酸(UA)、钾(K )、钠(Na )、氯(CL-)、钙(Ca )进行回顾性分析。结果肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBD)、门冬氨酸氨基转移酶(AST)、钾(K )与正常值比较,有明显的差异,其它生化结果均无显著意义。结论婴幼儿伤寒常缺乏典型的临床表现和特征,容易造成误诊和漏诊。本资料显示心肌酶学改变明显,因此心肌酶学应作为婴幼儿伤寒诊疗检验的重要指标。     

多重聚合酶链反应检测食品中致病性小肠结肠炎耶尔森菌和伤寒沙门氏菌

[目的 ]快速准确地检测致病性小肠结肠炎耶尔森菌和伤寒沙门氏菌 .[方法 ]根据小肠结肠炎耶尔森菌的ail基因和ST的H1 d基因顺序设计二对引物 ,通过聚合酶链反应检测食品中的小肠结肠炎耶尔森菌和伤寒沙门氏菌 ,扩增产物经电泳 ,分别出现与已知阳性对照细菌条带大小一致的 170和 4 5 8bp的ail和H1 d基因片断的条带时即判定该样品为阳性 .[结果和结论 ]本法特异性强、灵敏度高 ,能在60h内出结果 ,适用于食品中小肠结肠炎耶尔森菌和伤寒沙门氏菌的快速检验 .     

伤寒沙门菌bcfD基因的克隆表达

目的构建伤寒沙门菌BcfD基因的原核表达质粒,表达BcfD蛋白。方法PCR法从伤寒沙门菌Ty2菌株基因组中扩增bcfD目的基因,经克隆和亚克隆构建原核表达载体pET-30a-bcf,将该重组质粒转化E.coliBL21(DE3)并进行原核表达,用SDS-PAGE和免疫印迹分析表达蛋白。结果扩增到与bcfD基因预期大小相符的片段,测序证明与bcfD基因序列完全一致,SDS-PAGE显示该蛋白主要以包涵体的形式表达,相对分子质量为42×103,免疫印迹分析表明,表达产物与经用大肠杆菌吸附处理后的伤寒患者血清能进行免疫反应。结论成功构建了bcfD基因原核表达载体并在大肠杆菌中表达了目的蛋白。