鸭大肠杆菌超广谱β-内酰胺酶的检测及药物敏感性分析

分析鸭大肠杆菌的耐药性与超广谱β-内酰胺酶的关系,为临床相关感染的治疗提供理论依据。采用CLSI推荐的初步筛选试验和表型确证试验方法,检测了临床分离的12株鸭大肠杆菌产超广谱β-内酰胺酶的情况,用微量稀释法测定了环丙沙星等9种抗菌药对其的抗菌活性。临床分离的12株鸭大肠杆菌中,有4株产超广谱β-内酰胺酶,检出率为33%。产超广谱β-内酰胺酶的菌株对多种药物耐药,对氟喹诺酮类药物之间产生交叉耐药,对氟喹诺酮类、氨基糖苷类、头孢菌素类产生多重耐药性,产酶菌的耐药性明显大于非产酶菌。产超广谱β-内酰胺酶是鸭大肠杆菌对抗菌药物产生耐药性的主要机制之一。     

鸡源大肠杆菌ESBLs基因型检测及其耐药性分析

采用K-B法检测30株鸡源大肠杆菌对16种抗菌药物的耐药性,根据耐药表型和超广谱β-内酰胺酶(ESBLs)的基因型流行情况,指导临床合理用药.结果表明,24株大肠杆菌为产ESBLs株.扩增出了与预期片段大小相符的TEM型、SHV型、CTX-M型、OXA型基因.有5株同时检测出TEM和CTX-M基因.产酶大肠杆菌对氨苄西林、阿莫西林/克拉维酸、环丙沙星的耐药率100%.其多重耐药性明显比非产酶大肠杆菌严重.     

猪、鸡大肠杆菌ESBLs的基因型检测

【目的】检测致病性大肠埃希氏菌中超广谱β-内酰胺酶(Extendβ-lactamase,ESBLs)的基因型,指导兽医临床合理用药。【方法】对产生ESBL的5株致病性大肠埃希氏菌,设计并合成TEM-1和SHV-1两对引物,用PCR方法进行了ESBLs耐药质粒的DNA扩增、测序和基因型分析【结果】以产生ESBLs细菌的ESBLs耐药质粒为模板均扩增出了与预期片段大小相符的TEM型ESBL产物,但都没有扩出SHV型ESBL产物。【结论】结果提示国内畜禽产生ESBLs的致病性大肠埃希氏菌未通过质粒进行细菌间耐药基因的交换;ESBLs的产生与动物种属没有关系;为克服细菌的该类耐药性问题,应该进行头孢噻呋复方制剂的研究。     

Analysis of antibiotic resistance phenotypes and genes of Escherichia coli from healthy swine in Guizhou,China

This study was carried out to investigate the resistance phenotypes and resistance genes of Escherichia coli from swine in Guizhou, China. A total of 47 E. coli strains isolated between 2013 and 2018 were tested using the Kirby–Bauer (K–B) method to verify their resistance to 19 common clinical antimicrobials. Five classes consisting of 29 resistance genes were detected using polymerase chain reaction. The status regarding extended-spectrum β-lactamase (ESBL) and the relationship between ESBL CTX-M-type β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) genes were analysed. A total of 46 strains (97.9%) were found to be multidrug resistant. Amongst them, 27 strains (57.4%) were resistant to more than eight antimicrobials, and the maximum number of resistant antimicrobial agents was 16. Twenty antibiotic resistance genes were detected, including six β-lactamase genes blaTEM (74.5%), blaCTX-M-9G (29.8%), blaDHA (17.0%), blaCTX-M-1G (10.6%), blaSHV (8.5%), blaOXA (2.1%), five aminoglycoside-modifying enzyme genes aac(3′)-IV (93.6%), aadA1 (78.7%), aadA2 (76.6%), aac(3′)-II c (55.3%), aac(6′)-Ib (2.1%) and five amphenicol resistance genes floR (70.2%), cmlA (53.2%), cat2 (10.6%), cat1 (6.4%), cmlB (2.1%), three PMQR genes qnrS (55.3%), oqxA (53.2%), qepA (27.7%) and polypeptide resistance gene mcr-1 (40.4%). The detection rate of ESBL-positive strains was 80.9% (38/47) and ESBL TEM-type was the most abundant ESBLs. The percentage of the PMQR gene in blaCTX-M-positive strains was high, and the detection rate of blaCTX-M-9G was the highest in CTX-M type. It is clear that multiple drug resistant E. coli is common in healthy swine in this study. Extended-spectrum β-lactamase is very abundant in the E. coli strains isolated from swine and most of them are multiple compound genotypes.     

对超广谱β-内酰胺酶有抑制作用的中药的筛选

通过测定所选8种中药对产超广谱β-内酰胺酶(ESBLs)鸡大肠杆菌的最小抑菌浓度,来筛选对ESBLs大肠杆菌有抑菌活性的中药。结果表明所选中药对产ESBLs大肠杆菌都有不同程度的抑菌活性,其中以连翘和白芍的抑菌活性较高。根据本试验结果,可以选择连翘、白芍作为控制产ESBLs鸡大肠杆菌感染的有效措施。     

引起仔猪当前腹泻难治的病菌分析及药敏试验

采用实验室方法分离鉴定了引起猪腹泻的细菌,并对分离菌进行超广谱β-内酰胺酶（ESBLs）检测和对24种抗菌药、5种复方药的敏感性测定。结果显示,分离细菌为大肠杆菌、沙门氏菌、志贺氏菌、奇异变形杆菌,有的且产生ESBLs。药敏试验结果表明该菌对兽医临床中常用的β-内酰胺类抗生素、氟喹诺酮类、氯霉素类、氨基糖苷类等均产生耐药;对粘杆菌素、亚胺培南、美罗培南敏感,β-内酰胺类药物与酶抑制剂联用能使药物对细菌的最低抑菌浓度（M ICs）降低,因此复方β-内酰胺类药物是治疗猪腹泻的有效措施之一。     

产超广谱β-内酰胺酶（ESBLs）乳牛乳腺炎大肠杆菌的检测及其基因型分布

为了解采自内蒙古和上海地区的产超广谱β-内酰胺酶（ESBLs）乳牛乳腺炎大肠杆菌的流行特点、耐药性和基因型分布,采用美国临床实验室标准化委员会（CLSI）2005年推荐的初筛及纸片确认方法对内蒙古地区的58株和上海地区的22株乳牛乳腺炎大肠杆菌进行了ESBLs的检测及耐药性分析,并采用PCR扩增和PCR产物测序方法对产ESBLs菌株进行基因分型。结果显示,内蒙古地区检出6株产ESBLs菌株,阳性率为10.34%,其中,有1株菌携带TEM-1基因,有1株携带CTX-M-14型基因,而有3株同时携带TEM-1型和CTX-M-14型2种基因,只有1株菌未检出上述基因。上海地区未检出产ESBLs菌株。结果表明,产ESBLs菌株多表现为多重耐药,对各种抗菌药物的耐药率明显高于非产ESBLs菌株。     

乌鲁木齐市宠物犬、猫粪源大肠杆菌耐药性分析与ESBLs基因型检测

为分析宠物源大肠杆菌对抗菌药物的耐药情况及ESBLs耐药基因型，采集乌鲁木齐市181份宠物犬、猫肛拭子样品，分离获得120株大肠杆菌，通过Kirby-Bauer(K-B)药敏纸片法对分离株进行药物敏感性试验，采用PCR方法检测CTX-M(CTX-M-1G、CTX-M-2G和CTX-M-9G)、TEM和SHV三种超广谱β-内酰胺酶(ESBLs)基因。结果显示:120株大肠杆菌对四环素、氨苄西林、复方新诺明和哌拉西林的耐药率在35.8%~60.8%；对头孢噻肟、链霉素、庆大霉素、氯霉素、环丙沙星和多粘菌的耐药率在10.0%~29.2%；对亚胺培南、左氧氟沙星、阿米卡星、头孢他啶、氨曲南、氨苄西林-舒巴坦、阿莫西林、头孢吡肟和美罗培南的耐药率在0.8%~10.0%。58株(48.3%)大肠杆菌呈多重耐药表型(Multidrug resistance，MDR)；犬源分离株主要对3类抗生素产生耐药(16.9%，12/71)，猫源分离株主要对4类抗生素产生耐药(18.4%，9/49)；其中共检测出35株ESBLs阳性菌株，CTX-M-1G、CTX-M-9G和TEM基因的检出率分别为40.0%(14/35)、28.6%(10/35)和34.3%(12/35)，未扩增出CTX-M-2G和SHV基因。综上，从健康和患病宠物中均分离到多重耐药大肠杆菌，流行的ESBLs基因型以CTX-M和TEM为主。     

鬼针草不同溶媒提取物对耐药大肠杆菌抑菌效果初探

This paper researched antibacterial effect of different Bidens bipinnata L extracts against clinical ESBLs E.coli by means of micro-dilution assay and the present method of combining traditional Chinese herbs with western medicine in vitro. The results showed that it had good inhibitory effect under Bidens bipinnata L decoction, ethyl acetate extracts, acetone extracts and trichloromethane extracts in combination with antibiotic. And ethyl acetate extracts was the most efficient. Bidens bipinnata L decoction was the most widespread, and could reduce the MIC of different antibiotics.     

Study on the Antibacterial Effects of Queous Extract of Phryma leptostachya L.var. asiatica Hara Combined with Antibiotics in vitro against ESBLs-producing E.coli

In order to study the antibacterial effects in vitro of the aqueous extracts of Phryma leptostachya L.var.asiatica Hara combined with antibiotics against ESBLs-producing E.coli,we used broth micro-dilution method and micro-dilution checker-board technique to measure the minimal inhibitory concentrations (MIC) and the fractional inhibitory concentrations index (FICI) of Phryma leptostachya L.var.asiatica Hara and antibiotics.The results showed that the FICI of Phryma leptostachya L.var.asiatica Hara combined with ceftriaxone sodium,ceftazidime,cefotaxime sodium,ceftiofur sodium,amoxicillin,amikacin,azithromycin,fosfomycin,colistin,sulfamonomethoxine,rifampicin,ciprofloxacin,norfloxacin,levofloxacin,mequindox,lincomycin were 0.75,0.75,1.00,0.75,0.53,0.51,0.75,4.5,4.5,4.5,4.5 and 2.5,respectively.The results of the tests indicated that the aqueous extracts of Phryma leptostachya L.var.asiatica Hara combining with ceftriaxone sodium,ceftazidime,cefotaxime sodium,ceftiofur sodium,amoxicillin,amikacin,azithromycin,fosfomycin,colistin,sulfamonomethoxine and rifampicin showed additive effect;Combining with ciprofloxacin,norfloxacin,levofloxacin,mequindox and lincomycin had the antagonistic effect.