志贺菌毒力相关基因的PCR检测分析

目的：利用PCR方法对武汉地区近年来收集的17株志贺菌进行毒力相关基因检测并分析其分布情况。方法：采用8对引物set1A、set1B、shet2A、shet2B、ial、ipaH、stx1与virA分别对志贺菌中毒力相关基因进行检测,结合常规鉴定方法对PCR扩增结果进行分析。结果：SHET1仅在福氏志贺菌（福氏Ⅱ型、福氏Ⅳ型）分离株（包括其标准株）中存在;SH-ET2存在于各型志贺菌（包括其标准株）;ipaH基因存在于各种类型志贺菌（包括其标准株）;17株志贺菌中,引物shet2A和引物shet2B用于检测sen基因分别检出16株和13株;ial、virA在反复复苏的菌株中检出率有所下降,stx1基因只在痢疾志贺菌中检出。结论：志贺菌快速诊断方法（PCR）中应首选检测志贺菌相关毒力基因ipaH基因。     

山东省分离的霍乱弧菌毒力基因的研究

目的：了解山东省不同年代、不同地区收集的霍乱菌株携带的毒力基因情况、分布特点和变迁。方法：应用分子杂交、PCR技术对霍乱弧菌的CTX基因元件中的ctxA、zot基因，VPI毒力岛中的tcpA、tcpH、aldA、toxT、acfB基因，TLC因子中的cri、orf2—3基因，RTX基因簇中的rtxA、rtxC，以及toxR基因进行了检测。结果：用原位杂交检测，180株霍乱弧菌中有168株携带CTX遗传单元中的ctxA、zot、RS1基因，阳性率均为93．33％，表现出高度的一致性。用打点杂交检测不同时期的28株01群霍乱弧菌，所有被检菌都具有ToxR、RTX相关基因，在1980～1987年间分离的O1群霍乱弧菌流行株中，有92．86％携带编码TLC因子的基因，而1994～2000年间分离的流行株菌株中编码TLC因子的基因携带率仅有7．14％。Southern杂交结果显示，48株O1群霍乱弧菌可产生大小为9．4kb和6．5kb左右的两条ctxA杂交带，用zot基因探针进行杂交，11株O1群霍乱弧菌可产生与ctxA杂交带同样大小的条带。1株O139霍乱弧菌具有检测的所有毒力基因，但其ctxA（zot）杂交带与O1群霍乱弧菌有差异。结论：目前已知的霍乱弧菌毒力基因在山东省分离到的菌株中有广泛的分布，并且随时间的推移而发生变迁。     

中山市12株人源2型猪链球菌生物学特性研究及PFGE分型分析

目的 研究2016—2019年中山市人感染2型猪链球菌临床分离株的生物学特性及脉冲场凝胶电泳技术(pulsed field gel electrophoresis,PFGE)的分型,以期为临床防治猪链球病提供科学依据.方法 收集2016-2019年人感染2型猪链球菌12株,采用全自动细菌鉴定仪对其进行鉴定,应用核酸蛋白...     

鲍曼不动杆菌感染及治疗的研究进展

摘要：鲍曼不动杆菌是一种常见的医院感染病原体,因其高度耐药性而成为世界范围内感染治疗的首要难题之一。本文总结了鲍曼不动杆菌的分布特点、毒力因子、抗生素治疗、耐药性及新型治疗方法的最新研究成果,为临床了解鲍曼不动杆菌感染和治疗的现状提供参考。     

Molecular epidemiology of uropathogenic <Emphasis Type="Italic">Escherichia coli</Emphasis>

Escherichia coli is the most common cause of complicated as well as uncomplicated urinary tract infections (UTIs). Most of these uropathogenic E. coli (UPEC) strains exhibit certain virulence factors (VFs), including adhesins, iron uptake systems, synthesis of cytotoxins, and specific O:K:H serotypes. Molecular epidemiological studies of UPEC have contributed to the discovery of uropathogenic VFs, to an understanding of the pathogenesis of UTIs as ascending infections, and to the clarification of genetic linkages between different virulence genes such as pathogenicity islands (PAIs), which are one of the mechanisms for horizontal VF gene transfers between the same or related species. Uropathogenic VFs not only play an important role individually but also work cooperatively in a fine-tuned manner with coordinated regulation and expression.     

高致龋变形链球菌探针检测与龋病现状的关系

目的探讨唾液中gtfB基因片段检出率与龋病的关系,为寡核苷酸探针作为一种筛检方法用于临床奠定基础。方法以龋失补牙数（decayed missing of filled teeth,DMFT）记录439名不同龋敏感者口腔龋患现状,将其唾液样本中的菌体DNA抽提后行PCR扩增,其产物与gtfB探针行斑点杂交,记录阳性结果。使用SPSS 11.0统计软件计算DMFT和PCR扩增后探针杂交阳性结果之间的spearman等级相关系数。结果DMFT和PCR扩增后探针杂交阳性结果之间有密切相关性,r=0.914,P〈0.01。结论变形链球菌毒力因子gtfB寡脱氧核苷酸探针敏感性高而且特异性好,且PCR扩增后探针杂交阳性结果与受试个体龋病现状密切相关,可以进一步考察该探针检测结果与受试人群未来患龋风险的相关性。     

Endogenous endophthalmitis complicating<Emphasis Type="Italic"> Klebsiella pneumoniae</Emphasis> liver abscess in Europe: case report

Purpose: To report the first European case of endogenous endophthalmitis secondary to a liver abscess due to Klebsiella pneumoniae expressing MagA gene. Methods: A 33-year-old diabetic patient was admitted for fever and right upper quadrant abdominal pain. Abdominal computed tomography and laboratory studies were performed. On day 4 after admission, patient complained of a painful and red right eye with decreased vision. A complete ophthalmological examination, including visual acuity assessment, slit lamp examination and fundus ophthalmoscopy was started. Results: Klebsiella pneumoniae liver abscess was diagnosed and antibiotherapy initiated. Polymerase chain reaction revealed that the isolated Klebsiella pneumoniae was serotype K1 and positive for Mag A. Ophthalmological examination disclosed cells in the anterior chamber and an important vitritis. Fundus was barely visible. A diagnosis of Klebsiella pneumoniae endogenous endophthalmitis complicating liver abscess was made. Intravitreal injection of antibiotics resulted in a preservation of visual acuity. Conclusion: This report suggests that rather than being confined to Taiwan, endogenous endophthalmitis secondary to a liver abscess due to Klebsiella pneumoniae expressing MagA gene, is becoming a global problem.     

白念珠菌双组分信号转导系统及其致病性

白念珠菌和致病性真菌都具有双组分信号转导系统,主要对环境刺激作出反应.白念珠菌双组分信号转导系统由杂合组氨酸激酶或感受器激酶,磷酸组氨酸中间体和反应调节蛋白组成.这些双组分信号转导蛋白除参与细胞适应高渗透压刺激外,还在氧化刺激适应、白/灰色念珠菌转换、形态形成、细胞壁生物合成及毒力等方面发挥作用.哺乳动物细胞尚未发现双组分信号系统,因此,针对这些信号分子作为研发抗真菌药的新型药靶,能够有效地抗致病性真菌而不对宿主细胞造成损伤.