目的探讨临床分离携带psm-mec基因耐甲氧西林表皮葡萄球菌(MRSE)的SCCmec型别。方法收集临床分离并经全自动微生物鉴定系统准确鉴定的表皮葡萄球菌165株,通过PCR扩增esp和mecA基因准确鉴定MRSE,扩增psm-mec、fudoh和p221片段鉴定携带psm...目的探讨临床分离携带psm-mec基因耐甲氧西林表皮葡萄球菌(MRSE)的SCCmec型别。方法收集临床分离并经全自动微生物鉴定系统准确鉴定的表皮葡萄球菌165株,通过PCR扩增esp和mecA基因准确鉴定MRSE,扩增psm-mec、fudoh和p221片段鉴定携带psm-mec菌株。采用多重PCR对携带psm-mec基因的MRSE的mec、ccr和SCCmec进行分型。结果 138株MRSE菌株中,29株携带psm-mec基因,携带率为17.58%。多重PCR对mec和ccr分型结果显示,携带psm-mec基因MRSE均为Class A mec,但ccr型别存在明显的多样性。多重PCR对SCCmec分型结果显示,所有菌株均可扩增出Ⅱ型和/或Ⅲ型SCCmec条带,且为混合型别。结论临床分离携带psm-mec基因的MRSE的SCCmec具有同源性,以含Class A mec的携带Ⅱ型和/或Ⅲ型SCCmec为主。展开更多
目的研究血液来源携带psm-mec基因人葡萄球菌SCCmec型别和psm-mec基因与生物被膜的相关性,为其临床感染的防治提供依据。方法收集临床血液来源经全自动微生物鉴定仪确认的人葡萄球菌。通过PCR扩增mecA基因区分耐甲氧西林人葡萄球菌(meth...目的研究血液来源携带psm-mec基因人葡萄球菌SCCmec型别和psm-mec基因与生物被膜的相关性,为其临床感染的防治提供依据。方法收集临床血液来源经全自动微生物鉴定仪确认的人葡萄球菌。通过PCR扩增mecA基因区分耐甲氧西林人葡萄球菌(methicillin-resistant Staphylococcus hominis,MRSHo)和甲氧西林敏感人葡萄球菌(methicillin-susceptive Staphylococcus hominis,MSSHo)。体外粘附实验(Microtite Plate Assay,TCP)检测生物被膜。PCR扩增psm-mec基因并测序,分析其与生物被膜的相关性。PCR扩增psm-mec与mecR1及xylR基因的间隔序列和对psm-mec基因阳性菌株做SCCmec、mec和ccr型别检测,探究其在SCCmec上的定位与分布特征。结果共收集菌株55株,其中46株检出mecA基因为MRSHo,18株携带psm-mec基因,35株产生物被膜。携带与未携带psm-mec基因的菌株形成生物被膜的比率分别为83.33%和54.1%,二者差异显著(P=0.03)。DNA测序显示,3株psm-mec阳性生物被膜阴性的菌株中,2株于psm-mec编码区上游-12处发现G>A的点突变。所有psm-mec与mecR1及xylR的基因间隔序列阳性。携带psm-mec基因菌株分为,2株SCCmecⅢ型,7株Ⅲ型的变异型,9株SCCmec新型别;所有菌株均为Class A类mec;6株为ccr type 1,1株为ccr type 1+2,2株为ccr type 1+3,2株为ccr type 3,7株未扩增出ccr。结论在血液来源人葡萄球菌中,psm-mec基因与生物被膜存在相关性,其定位于mecR1与xylR两个基因之间,主要分布于SCCmecⅢ型、Ⅲ型变异型和新型别中,ccr基因存在高度变异,是造成SCCmec多态性的原因。展开更多
MRSA is able to generate a modified variety of penicillin binding protein named as PBP2a instead of PBP which makes it resistant against penicillin and methicillin. Production of PBP2a is due to the presence of a gene...MRSA is able to generate a modified variety of penicillin binding protein named as PBP2a instead of PBP which makes it resistant against penicillin and methicillin. Production of PBP2a is due to the presence of a gene on Staphylococcal cassette chromosome or SCC termed as “mec-A gene”. SCC is a mobile genetic element carrying many resistance genes. It is because of current antibiotic selection pressure that by now there are eight types (I - VIII) of SCCmec. This research has been designed to determine frequency of SCCmec type IV and V in clinical isolates of MRSA. A total of 70 presumptive MRSA isolates collected from a tertiary care hospital of Lahore were cultured on blood agar, incubated overnight at 37°C aerobically. Next day, they were examined for cultural characteristics, colonial morphology, gram stain, and biochemical profile. Confirmation of MRSA was done by phenotypic disk diffusion method according to (CLSI) 2013 guidelines. mecA gene was also detected at molecular level. Molecular identification of SCCmec type IV and V was done by Nested PCR strategy. A total of 50 isolates were confirmed to be MRSA Molecular detection of SCCmec type IV and V revealed that 11 isolates (22%) possess SCCmec type IV and only 2 isolate (4%) carries SCCmec type V. It is obvious from results that SCCmec type IV and V are present in our population too. Larger study (with larger sample size) might be undertaken to find out actual emergence of SCCmec type IV and V in our population.展开更多
Data from a prospective, randomized, open-label, active-controlled, multicenter, Phase 4 study comparing oral or intravenous linezolid with intravenous vancomycin for treatment of complicated skin and soft-tissue infe...Data from a prospective, randomized, open-label, active-controlled, multicenter, Phase 4 study comparing oral or intravenous linezolid with intravenous vancomycin for treatment of complicated skin and soft-tissue infections caused by methicillin resistant Staphylococcus aureus was used to determine the association between staphylococcal cassette chromosome mec (SCCmec) type and patient’s clinical presentation, infection severity, intravenous therapy duration and length of stay (LOS). Compared to SCCmec types I, II, and III, SCCmec type IV, PVL+ was associated with more frequent presentation of abscesses, lower severity scores, and shorter intravenous therapy duration and LOS in both treatment groups.展开更多
文摘目的探讨临床分离携带psm-mec基因耐甲氧西林表皮葡萄球菌(MRSE)的SCCmec型别。方法收集临床分离并经全自动微生物鉴定系统准确鉴定的表皮葡萄球菌165株,通过PCR扩增esp和mecA基因准确鉴定MRSE,扩增psm-mec、fudoh和p221片段鉴定携带psm-mec菌株。采用多重PCR对携带psm-mec基因的MRSE的mec、ccr和SCCmec进行分型。结果 138株MRSE菌株中,29株携带psm-mec基因,携带率为17.58%。多重PCR对mec和ccr分型结果显示,携带psm-mec基因MRSE均为Class A mec,但ccr型别存在明显的多样性。多重PCR对SCCmec分型结果显示,所有菌株均可扩增出Ⅱ型和/或Ⅲ型SCCmec条带,且为混合型别。结论临床分离携带psm-mec基因的MRSE的SCCmec具有同源性,以含Class A mec的携带Ⅱ型和/或Ⅲ型SCCmec为主。
文摘目的研究血液来源携带psm-mec基因人葡萄球菌SCCmec型别和psm-mec基因与生物被膜的相关性,为其临床感染的防治提供依据。方法收集临床血液来源经全自动微生物鉴定仪确认的人葡萄球菌。通过PCR扩增mecA基因区分耐甲氧西林人葡萄球菌(methicillin-resistant Staphylococcus hominis,MRSHo)和甲氧西林敏感人葡萄球菌(methicillin-susceptive Staphylococcus hominis,MSSHo)。体外粘附实验(Microtite Plate Assay,TCP)检测生物被膜。PCR扩增psm-mec基因并测序,分析其与生物被膜的相关性。PCR扩增psm-mec与mecR1及xylR基因的间隔序列和对psm-mec基因阳性菌株做SCCmec、mec和ccr型别检测,探究其在SCCmec上的定位与分布特征。结果共收集菌株55株,其中46株检出mecA基因为MRSHo,18株携带psm-mec基因,35株产生物被膜。携带与未携带psm-mec基因的菌株形成生物被膜的比率分别为83.33%和54.1%,二者差异显著(P=0.03)。DNA测序显示,3株psm-mec阳性生物被膜阴性的菌株中,2株于psm-mec编码区上游-12处发现G>A的点突变。所有psm-mec与mecR1及xylR的基因间隔序列阳性。携带psm-mec基因菌株分为,2株SCCmecⅢ型,7株Ⅲ型的变异型,9株SCCmec新型别;所有菌株均为Class A类mec;6株为ccr type 1,1株为ccr type 1+2,2株为ccr type 1+3,2株为ccr type 3,7株未扩增出ccr。结论在血液来源人葡萄球菌中,psm-mec基因与生物被膜存在相关性,其定位于mecR1与xylR两个基因之间,主要分布于SCCmecⅢ型、Ⅲ型变异型和新型别中,ccr基因存在高度变异,是造成SCCmec多态性的原因。
文摘MRSA is able to generate a modified variety of penicillin binding protein named as PBP2a instead of PBP which makes it resistant against penicillin and methicillin. Production of PBP2a is due to the presence of a gene on Staphylococcal cassette chromosome or SCC termed as “mec-A gene”. SCC is a mobile genetic element carrying many resistance genes. It is because of current antibiotic selection pressure that by now there are eight types (I - VIII) of SCCmec. This research has been designed to determine frequency of SCCmec type IV and V in clinical isolates of MRSA. A total of 70 presumptive MRSA isolates collected from a tertiary care hospital of Lahore were cultured on blood agar, incubated overnight at 37°C aerobically. Next day, they were examined for cultural characteristics, colonial morphology, gram stain, and biochemical profile. Confirmation of MRSA was done by phenotypic disk diffusion method according to (CLSI) 2013 guidelines. mecA gene was also detected at molecular level. Molecular identification of SCCmec type IV and V was done by Nested PCR strategy. A total of 50 isolates were confirmed to be MRSA Molecular detection of SCCmec type IV and V revealed that 11 isolates (22%) possess SCCmec type IV and only 2 isolate (4%) carries SCCmec type V. It is obvious from results that SCCmec type IV and V are present in our population too. Larger study (with larger sample size) might be undertaken to find out actual emergence of SCCmec type IV and V in our population.
文摘Data from a prospective, randomized, open-label, active-controlled, multicenter, Phase 4 study comparing oral or intravenous linezolid with intravenous vancomycin for treatment of complicated skin and soft-tissue infections caused by methicillin resistant Staphylococcus aureus was used to determine the association between staphylococcal cassette chromosome mec (SCCmec) type and patient’s clinical presentation, infection severity, intravenous therapy duration and length of stay (LOS). Compared to SCCmec types I, II, and III, SCCmec type IV, PVL+ was associated with more frequent presentation of abscesses, lower severity scores, and shorter intravenous therapy duration and LOS in both treatment groups.
