目的:了解内蒙古自治区鼠疫自然疫源地鼠疫耶尔森菌(鼠疫菌)对11种抗生素的耐药情况,为科学有效地选择抗生素治疗鼠疫提供理论依据。方法:收集137株分离自内蒙古自治区鼠疫自然疫源地不同时间、不同地区、不同宿主和媒介的鼠疫菌,采用...目的:了解内蒙古自治区鼠疫自然疫源地鼠疫耶尔森菌(鼠疫菌)对11种抗生素的耐药情况,为科学有效地选择抗生素治疗鼠疫提供理论依据。方法:收集137株分离自内蒙古自治区鼠疫自然疫源地不同时间、不同地区、不同宿主和媒介的鼠疫菌,采用美国临床和实验室标准协会(Clinical and Laboratory Standard Institute,CLSI)药敏试验方法中的琼脂稀释法,分别测定氧氟沙星、环丙沙星、硫酸卡那霉素、硫酸链霉素、头孢曲松钠、氨苄青霉素钠、氯霉素、盐酸壮观霉素、头孢呋辛钠、盐酸四环素、磺胺甲恶唑-甲氧苄啶共11种抗生素对137株鼠疫菌的最低抑菌浓度(MIC),计算MIC 50、MIC 90(能抑制50%、90%细菌生长的最低药物浓度);并根据CLSI标准判定其敏感性。结果:检测的137株鼠疫菌未发现对氧氟沙星、环丙沙星、硫酸卡那霉素、硫酸链霉素、头孢曲松钠、氨苄青霉素钠、氯霉素、盐酸壮观霉素、头孢呋辛钠、盐酸四环素和磺胺甲恶唑-甲氧苄啶具有单独或多重耐药性。根据CLSI标准,137株鼠疫菌对11种抗生素均敏感;其中,氧氟沙星、环丙沙星、头孢曲松钠及磺胺甲恶唑-甲氧苄啶的抗菌活性较高,MIC 90均<0.250μg/ml;盐酸壮观霉素的抗菌活性最低,MIC 90为16.000μg/ml。结论:内蒙古自治区鼠疫自然疫源地内分离的鼠疫菌未发现对11种抗生素具有单独或多重耐药性,应对鼠疫菌进行持续的耐药监测,为临床用药提供依据。展开更多
AIM: To investigate the distribution of 12 high-pathogenicity island (HPI) genes and the relation between HPI genes and expression of yersiniabactin (Ybt) in enteroaggregative E.coli(EAggEC) isolated from Chinese diar...AIM: To investigate the distribution of 12 high-pathogenicity island (HPI) genes and the relation between HPI genes and expression of yersiniabactin (Ybt) in enteroaggregative E.coli(EAggEC) isolated from Chinese diarrhea patients.METHODS: The distribution of 12 HPI genes was investigated by PCR and DNA hybridization in two prototype strains of EAggEC, EAggEC 17-2, EAggEC O42, and 6 clinical EAggEC isolates from China. The production of siderophore Ybt in HPI-positive strains was detected by reporter gene bioassay to determine the relation between HPI genes and expression of Ybt. Flow cytometry was used to detect fluorescent signal of the reporter strain that could designate production of Ybt.RESULTS: Seven strains were HPI-positive and one strain was HPI-negative. Six of the seven HPI-positive strains were inserted into asnT-tRNA site. Moreover, seven EAggEC HPI-positive strains revealed enhanced fluorescence signal but the EAggEC HPI-negative strain did not. However, there was a difference in Ybt expression condition and level among these seven EAggEC HPI-positive strains. Although UFT073 strain, the prototype strain of uropathogenic E.coli(UPEC), carried the complete HPI core part, we did not detect the expression of Ybt in it.CONCLUSION: EAggEC HPI-positive strains can express the Ybt system, but the presence of HPI core part does not mean the functional expression of Ybt.展开更多
文摘目的:了解内蒙古自治区鼠疫自然疫源地鼠疫耶尔森菌(鼠疫菌)对11种抗生素的耐药情况,为科学有效地选择抗生素治疗鼠疫提供理论依据。方法:收集137株分离自内蒙古自治区鼠疫自然疫源地不同时间、不同地区、不同宿主和媒介的鼠疫菌,采用美国临床和实验室标准协会(Clinical and Laboratory Standard Institute,CLSI)药敏试验方法中的琼脂稀释法,分别测定氧氟沙星、环丙沙星、硫酸卡那霉素、硫酸链霉素、头孢曲松钠、氨苄青霉素钠、氯霉素、盐酸壮观霉素、头孢呋辛钠、盐酸四环素、磺胺甲恶唑-甲氧苄啶共11种抗生素对137株鼠疫菌的最低抑菌浓度(MIC),计算MIC 50、MIC 90(能抑制50%、90%细菌生长的最低药物浓度);并根据CLSI标准判定其敏感性。结果:检测的137株鼠疫菌未发现对氧氟沙星、环丙沙星、硫酸卡那霉素、硫酸链霉素、头孢曲松钠、氨苄青霉素钠、氯霉素、盐酸壮观霉素、头孢呋辛钠、盐酸四环素和磺胺甲恶唑-甲氧苄啶具有单独或多重耐药性。根据CLSI标准,137株鼠疫菌对11种抗生素均敏感;其中,氧氟沙星、环丙沙星、头孢曲松钠及磺胺甲恶唑-甲氧苄啶的抗菌活性较高,MIC 90均<0.250μg/ml;盐酸壮观霉素的抗菌活性最低,MIC 90为16.000μg/ml。结论:内蒙古自治区鼠疫自然疫源地内分离的鼠疫菌未发现对11种抗生素具有单独或多重耐药性,应对鼠疫菌进行持续的耐药监测,为临床用药提供依据。
基金Supported by the National Basic Research Program of Ministry of Science and Technology of China, No. G1999054101
文摘AIM: To investigate the distribution of 12 high-pathogenicity island (HPI) genes and the relation between HPI genes and expression of yersiniabactin (Ybt) in enteroaggregative E.coli(EAggEC) isolated from Chinese diarrhea patients.METHODS: The distribution of 12 HPI genes was investigated by PCR and DNA hybridization in two prototype strains of EAggEC, EAggEC 17-2, EAggEC O42, and 6 clinical EAggEC isolates from China. The production of siderophore Ybt in HPI-positive strains was detected by reporter gene bioassay to determine the relation between HPI genes and expression of Ybt. Flow cytometry was used to detect fluorescent signal of the reporter strain that could designate production of Ybt.RESULTS: Seven strains were HPI-positive and one strain was HPI-negative. Six of the seven HPI-positive strains were inserted into asnT-tRNA site. Moreover, seven EAggEC HPI-positive strains revealed enhanced fluorescence signal but the EAggEC HPI-negative strain did not. However, there was a difference in Ybt expression condition and level among these seven EAggEC HPI-positive strains. Although UFT073 strain, the prototype strain of uropathogenic E.coli(UPEC), carried the complete HPI core part, we did not detect the expression of Ybt in it.CONCLUSION: EAggEC HPI-positive strains can express the Ybt system, but the presence of HPI core part does not mean the functional expression of Ybt.
