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1.
目的分析一株同时产KPC-2和NDM-5碳青霉烯酶的肺炎克雷伯菌耐药基因特征。方法肺炎克雷伯菌KPN-hnqyy分离自我院血液科一位患者的粪便标本, 使用仪器BD Phenix-M50鉴定菌株并测定最小抑菌浓度;酶联免疫层析试验和PCR方法检测碳青霉烯酶基因型;接合试验检测相关质粒的转移性;PacBio和Illumina平台对菌株全基因组测序, 并在BacWGSTdb数据库中检索菌株MLST分型、耐药基因和质粒类型, 使用软件Easyfig2.2.3比对基因组和开放读码框序列, BRIG v0.95生成可视化质粒圈图。结果肺炎克雷伯菌KPN-hnqyy对碳青霉烯类抗生素耐药, MLST分型为ST11型, blaKPC-2和blaNDM-5碳青霉烯酶基因阳性;接合子blaKPC-2基因阳性, blaNDM-5阴性;全基因组测序显示菌株含有1个染色体和3个质粒;肺炎克雷伯菌KP69和KP19-2029等与本研究菌株染色体基因组相似性大于99.9%, 且其各自携带的不同种类的质粒上含有相似的IncR和IncFⅠ耐药基因融合区, blaKPC-2基因位于此融合区中一个由T...  相似文献   

2.
目的 调查我院产ESBL肺炎克雷伯菌临床分离株16S rRNA甲基化酶基因的分布以及与耐药谱的关系,并初步探讨其在分子流行病学分析中的作用.方法 收集我院临床2010年3月至9月分离出69株非重复产ESBL肺炎克雷伯菌,采用PCR法检测16S rRNA 甲基化酶基因,并对阳性菌株进行ESBL基因及整合子基因分析,通过DNA直接测序确定.质粒接合试验和质粒消除试验确定16S rRNA甲基化酶基因的传播途径,利用ERIC-PCR技术进行基因分型.结果 69株产ESBL肺炎克雷伯菌中有rmtB阳性菌株20株(28.9%),其中2株同时携带有rmtB和armA.在20株产16SrRNA甲基化酶菌株中,均携带有CTX-M基因,测序显示14株CTX-M-14基因,6株CTX-M-15基因;14株携带有TEM-1基因;8株携带有SHV基因,测序显示5株SHV-12基因,3株SHV-11基因;3株携带有OXA-10基因;3株携带有VBE-1基因.另有12株携带有int1阳性,含有5种不同的耐药基因盒,分别携带drfA25、drfA1、drfA12、aadA1、aadA2、sat和blaVEB-1基因.ERIC-PCR法显示20株16SrRNA甲基化酶基因阳性的肺炎克雷伯菌主要分为5型,A型为优势流行克隆株.质粒接合和消除试验发现A型克隆株KP5和KP16 rmtB均位于一质粒上并通过接合传播.结论 本院产ESBL肺炎克雷伯菌临床分离株中存在16S rRNA甲基化酶基因rmtB的普遍流行,导致对多种氨基糖苷类抗生素高水平耐药.rmtB可通过水平基因传播和克隆传播的两种方式进行播散,并且存在同时产ESBLs、16S rRNA甲基化酶和Ⅰ类整合子的肺炎克雷伯菌的传播.  相似文献   

3.
目的研究大肠埃希菌和肺炎克雷伯菌同时产超广谱β内酰胺酶(ESBL)及质粒型Ampc酶菌株的比率及其基因型。方法收集北京两家教学医院2001--2002年产ESBL且对头孢西叮耐药的59株大肠埃希菌和21株肺炎克雷伯菌,采用等电聚焦电泳测定β内酰胺酶的等电点;接合试验证实酶基因有无可转移性,并用碱裂解法提取质粒;采用多重聚合酶链式反应(multiplex polymerase chain reaction,MPCR)及序列分析确定质粒AmpC酶的基因型。脉冲场凝胶电泳(pulsed field gelel ectrophoresis,PFGE)确定耐药菌株的亲缘关系。结果北京两家医院ESBL中质粒型AmCZ酶的发生率,大肠埃希菌分别为0和2%,肺炎克雷伯菌则分别为9.7%和17.1%。1株大肠埃希菌及9株肺炎克雷伯菌产生DHA-1型质粒AmpC酶,同时也产CTX-3型(6株)或CTX—M-14(1株)或SHV-12(3株)型ESBL。10株中,3株肺炎克雷伯菌可将头孢西叮耐药性传给受体菌。这10株菌均至少携带1个约33—36kb的大质粒,未发现质粒的传播。PFGE发现这10株菌来自不同的克隆株。结论北京地区发现同时产DHA-1质粒AmpC型及CTX—M型ESBL的肺炎克雷伯菌,它们来自不同的克隆。  相似文献   

4.
目的 对临床分离的碳青霉烯类抗生素耐药的肠杆菌科细菌进行耐药机制研究及流行病学调查.方法 收集2010年1月至2010年8月,对碳青霉烯类抗生素敏感性下降的肠杆菌科细菌18株,全自动微生物鉴定仪检测细菌对常见抗生素最低抑菌浓度(MIC),纸片法检测细菌产超广谱β-内酰胺酶、头孢菌素酶、碳青霉烯酶的情况,并用PCR扩增、DNA测序确定所产碳青霉烯酶基因型.脉冲场凝胶电泳对耐药菌进行同源性分析.结果 8株耐药菌全部检出ESBLs酶、AmpC酶,17株检出KPC-2酶,3株EDTA纸片法阳性提示产其他金属碳青霉烯酶,其中两株合并产KPC-2.脉冲场凝胶电泳结果显示15株肺炎克雷伯菌分为6种带型.结论 KPC-2碳青霉烯酶是造成肠杆菌科细菌对碳青霉烯类抗生素敏感性下降的主要原因,并在我院局部短暂流行,携带KPC-2基因的临床菌株同时携带多种耐药基因.  相似文献   

5.
目的 研究我院普外科重症监护病房(ICU)出现的对碳青霉烯类抗菌药物耐药的大肠埃希菌分子流行病学特征和碳青霉烯耐药机制.方法 采用琼脂稀释法检测分离株的抗菌药物敏感性,采用脉冲场琼脂糖凝胶电泳(PFGE)研究碳青霉烯类耐药的大肠埃希菌分子流行病学机制,采用特异性PCR、DNA测序分析、接合试验、质粒提取和质粒转化试验、外膜蛋白分析等技术研究碳青霉烯耐药的分子机制.结果 我院分离的14株碳青霉烯耐药菌分别属于10个流行克隆型,均表现对包括亚胺培南和美罗培南在内多种抗菌药物耐药,碳青霉烯类耐药基因扩增显示均携带KPC-2型碳青霉烯酶基因,质粒提取与转化试验显示KPC-2定位于约56 kb大小的质粒上,SDS-PAGE分析发现耐药株多出现外膜蛋白的改变.结论 我院出现多个流行克隆型的碳青霉烯类耐药的大肠埃希菌,质粒型碳青霉烯酶KPC-2是我院泛耐型大肠埃希菌介导对碳青霉烯类耐药的主要原因,外膜孔蛋白改变参与介导大肠埃希菌对碳青霉烯类高度耐药.  相似文献   

6.
目的 探讨耐碳青霉烯类药物肺炎克雷伯菌的耐药机制.方法 对南京地区两家三甲综合性医院的耐碳青霉烯抗菌药物肺炎克雷伯菌临床分离株,采用PCR方法对其40种β-内酰胺酶基因、膜孔蛋白编码基因及KPC-ISKpn6连锁进行检测,PCR阳性产物进行测序,测序结果BLAST对比分析.结果 24株耐碳青霉烯类药物肺炎克雷伯菌的A类β-内酰胺酶编码基因TEM-1及SHV的阳性检出率为100% (24/24)、KPC-2的阳性检出率为95.8% (23/24)、LAP-2的阳性检出率为45.8% (11/24),C类β-内酰胺酶编码基因DHA的阳性检出率为4.2% (1/24),KPC-ISKpn6连锁检测阳性率为95.8% (23/24),膜孔蛋白编码基因ompK35与ompK36的突变率分别为95.8% (23/24)及100%(24/24).结论 本组肺炎克雷伯菌β-内酰胺酶TEM-1、SHV、KPC-2、LAP-2的携带率较高,其中KPC-2的高携带率及膜孔蛋白编码基因ompK35、ompK36的高突变率是本组肺炎克雷伯菌对碳青霉烯类抗菌药物耐药的主要机制;插入序列ISKpn6可能参与了KPC-2基因的介导.  相似文献   

7.
目的 研究碳青霉烯耐药摩根摩根菌的分子流行病学及其耐药机制.方法 2010年10月-2011年2月从杭州市中医院分离到7株碳青霉烯不敏感的摩根摩根菌.脉冲场凝胶电泳(PFGE)分析菌株之间的同源性;琼脂稀释法测定抗生素对细菌的最低抑菌浓度(MIC);接合试验、质粒图谱分析、特异性PCR扩增和序列分析等研究细菌对碳青霉烯耐药的分子机制.结果 分离自急诊监护病房的6株摩根摩根菌PFGE条带完全相同或相差1~3个条带;分离自重症监护病房的1株摩根摩根菌与其他6株PFGE条带差异明显.7株摩根摩根菌的耐药模式基本相同.亚胺培南、美罗培南和厄他培南的MIC值差异较大,分别为8μg/ml(耐药)、1μg/ml(敏感)和0.25~0.50μg/ml(敏感或中介耐药).7株摩根摩根菌对青霉素类、氨曲南和环丙沙星耐药,对头孢菌素类耐药或敏感,对阿米卡星敏感.接合试验使大肠埃希菌EC600对碳青霉烯类抗生素由敏感变为耐药,对其他β-内酰胺类抗生素也均耐药.摩根摩根菌及转移接合子均含有一个约为60kb的质粒.PCR扩增及测序表明摩根摩根菌及转移接合子均产KPC-2型碳青霉烯酶,且携带qnrS1基因.结论 首次在摩根摩根菌中检测到KPC-2型碳青霉烯酶,KPC-2是引起摩根摩根菌对碳青霉烯类不敏感的主要原因.  相似文献   

8.
目的 对从同一标本中分离的碳青霉烯类药物耐药的肺炎克雷伯菌和摩根摩根菌进行耐药机制相关性分析.方法 琼脂稀释法进行药物敏感试验;特异性PCR扩增和序列分析检测介导耐碳青霉烯类药物的相关基因;接合试验、质粒提取和耐药基因周围序列分析耐药的可传递性、耐药质粒的同源性及耐药基因的遗传背景;提取外膜蛋白分析菌株外膜蛋白的改变.结果 2株分离菌均产碳青霉烯酶并扩增出介导碳青霉烯类耐药的KPC-2型基因;质粒接合试验成功传递了对碳青霉烯类药物的耐药性,耐药基因被携带在2个大小不同但耐药基因周围序列完全相同的质粒上;其中摩根摩根菌耐药株缺失了相对分子质量约为38×103的外膜蛋白同时出现36×103的外膜蛋白而肺炎克雷伯菌则缺失了外膜蛋白OMPK36.结论 2株分离菌均携带KPC-2基因.该基因由2个大小不同的质粒携带,同一复合转座子介导了KPC-2基因在2株细菌的不同质粒上转移.同时外膜蛋白缺失参与了对碳青霉烯类抗生素耐药.
Abstract:
Objective To investigate the relationship of resistance mechanisms of a Klebsiella pneumoniae strain and a Morganella morganii strain resistance to carbapenems isolated from a single specimen. Methods Sensibility of antimicrobial agents was detected by agar dilution method. Specific PCR and DNA sequence analysis were performed to detect resistance genes. Plasmid feature was detected by plasmid conjugation and electrophoresis analysis. Genetic environment around blaKPC was analyzed with sequencing. The changes of outer membrane permeability were analyzed with electrophoresis of outer membrane proteins. Results blaKPC-2 was detected in 2 original isolates strains and their transconjugants. Carbapenem-resistance was successfully transfered by conjugation experiments. blaKPC-2 was located on dissimilar plasmids, but genetic environment around blaKPC-2 was the same sequence. The Morganella morganii isolate showed a loss of 38 ×103 OMPs and an additional 36 ×103 OMPs appearance, while the Klebsiella pneumoniae isolate showed a loss of OMPK36. Conclusion blaKPC-2 was detected in 2 isolates. This gene encoded by two plasmids with different sizes was located on the same composite transposon. The lack of outer membrane proteins could also play an important role causing isolates to exhibite resistance to carbapenems.  相似文献   

9.
目的重症医学科染KPC-2肺炎克雷伯菌的耐药及同源性情况。方法从2018年4月至2019年2月于我院重症医学科室治疗的患者中提取40例耐碳青霉烯类肺炎克雷伯菌(CRKPN)菌株,对待测菌株进行药敏性试验、mCIM(改良碳青霉烯灭活试验)和eCIM(EDTA改良碳青霉烯灭活试验)联合试验,采用PCR扩增法检测待测菌的耐药基因并进行基因序列检测,采用PFGE对待测菌进行同源性分析。结果在16种抗菌药中,待测菌仅对阿米卡星(27.50%)、庆大霉素(17.50%)、妥布霉素(25.00%)、替加环素(100.00%)以及复方新诺明(55.00%)有敏感性;mCIM和eCIM试验结果显示40株CRKPN均产丝氨酸碳青霉烯酶;PCR试验结果显示待测菌株携带KPC基因阳性率为100%;选择ICU分离的17株CRKPN做PFGE,同源性结果分析显示该病区存在耐碳青霉烯肺炎克雷伯的克隆传播。结论我院重症医学科分离的CRKPN细菌的耐药机制是产丝氨酸碳青霉烯酶,酶基因为KPC-2型,PFGE结果分析显示我院重症医学科存在耐碳青霉烯肺炎克雷伯的克隆传播,需要加强院感监控工作。  相似文献   

10.
目的 探讨上海交通大学医学院附属瑞金医院分离的5株泛耐药阴沟肠杆菌产碳青霉烯酶及16S rRNA甲基化酶的情况及两者之间的相关性.方法 用E test法检测5株泛耐药阴沟肠杆菌对10种抗菌药物的MIC值.PCR扩增16S rRNA甲基化酶基因armA、mtA、rmtB、rmtC、rmtD、npmA,β-内酰胺酶基因TEM、SHV、CTX-M-1、CTX-M-2、CTX-M-8、CTX-M-9、CTX-M-25、PER-1、VEB-1.鸟枪克隆法克隆碳青霉烯酶基因,并对克隆片段进行测序.质粒接合试验验证碳青霉烯酶基因及16S rRNA甲基化酶基因是否具有转移性.脉冲场凝胶电泳(PFGE)法对5株菌进行分子分型.等电聚焦电泳法检测β-内酰胺酶等电点.Southern杂交法对耐药决定因子进行定位.结果 5株阴沟肠杆菌对10种抗菌药物的MIC值均>32 mg/L.克隆的碳青霉稀酶基因为blaKPC-2,酶编码基因上游为一转座酶基因,两侧为复制靶位,下游为ISKpn6的插入序列,该序列包括一个重复序列和tnpA转座子,酶编码基因位于54.2 kb的一个非接合性大质粒上.等电聚焦电泳显示5株菌均产4种β-内酰胺酶(TEM-1,pI5.4;KPC-2,pI6.7;SHV-12,pI8.2;CTX-M-14,pI8.4).16S rRNA甲基化酶基因位于接合性质粒上,而blaKPC-2基因则位于非接合性质粒上,5株菌PFGE型别一致.结论 5株泛耐药阴沟肠杆菌对碳青霉烯类耐药由产碳青霉烯酶KPC-2所介导.blaKPC-2与armA型16S rRNA甲基化酶基因由两条不同的质粒编码,不存在相关性.临床医院应加强监控,以防止交叉感染.  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

15.
16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

19.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

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