重症监护病房中革兰氏阴性杆菌的耐药性分析

目的：调查我院重症监护病房革兰氏阴性杆菌耐药状况，了解超广谱β－内酰胺酶（ESBLs)菌株的发生率。方法：用E试验法测定100株革兰氏阴性杆菌对12种抗生素的最低抑菌浓度（MIC）。结果：亚胺培南、ertapenem(MK-0826)和阿米卡星对所有受试菌保持较高抗菌活性，细菌耐药率分别为4％、15％和17％；头孢他啶、头孢吡肟、头孢哌酮／舒巴坦耐药率分别为33％、25％和26％，其他抗生素耐药率在44％－51％。与2001年我院调查水平相比，头孢哌酮／舒巴坦耐药率增加15％，其他抗生素耐药率变化不大。用头孢噻肟／头孢噻肟＋克拉维酸和头孢他啶／头孢他啶＋克拉维酸分别筛选出ESBLs产生菌13株和11株，其中大肠埃希氏菌产酶率最高，分别为21．7％（5／23）和34．8％（8／23），肺炎克雷伯氏菌其次，分别为23．8％（5／21）和9．5％（2／21）。抗菌活性最强的是亚胺培南，对所有大肠埃希氏菌和肺炎克雷伯氏菌ESBLs菌株都敏感。而临床常用的头孢哌酮／舒巴坦和替卡西林／克拉维酸并未体现酶抑制剂优越性，耐药菌株多。结论：亚胺培南抑菌率最高，对ESBLs产生菌有较强的抗菌活性，而加酶抑制剂抗生素的滥用，已造成细菌对其耐药率升高，且对付产酶耐药株感染逐渐失去优势。     

我院铜绿假单胞菌和鲍曼不动杆菌的耐药性分析

目的探讨临床铜绿假单胞菌、鲍曼不动杆菌的分布特点及耐药情况,以指导临床合理使用抗生素。方法回顾性分析医院2008年1月至12月分离的铜绿假单胞菌、鲍曼不动杆菌的药物敏感性试验结果 ,剔除重复菌株,药物敏感性试验采用纸片扩散（K-B）法。结果分离出的238株铜绿假单胞菌和127株鲍曼不动杆菌主要来源于呼吸道标本;238株铜绿假单胞菌对常用抗菌药物均有不同程度的耐药,其中对阿米卡星、美洛培南、亚胺培南、哌拉西林他唑巴坦的敏感率分别为87.54%,86.17%,87.69%和86.41%,对头孢曲松和复方磺胺甲唑的敏感率仅为0.97%和3.40%;127株鲍曼不动杆菌对阿米卡星的敏感率最高,达95.27%,对头孢曲松的敏感率仅为4.05%。结论铜绿假单胞菌、鲍曼不动杆菌呈多重耐药现象,必须加强耐药监测,根据药物敏感性试验结果合理选择抗生素。     

多重耐药铜绿假单胞菌产酶状况及药物敏感性研究

目的了解本地区多重耐药铜绿假单胞菌产酶情况及耐药性,为临床治疗及感染控制提供依据。方法采用手工法及法国生物梅里埃鉴定系统对菌种进行鉴定,采用K-B琼脂扩散法进行药敏实验检测,改良三维试验、协同法分别对细菌ESBLs酶、AmpC酶、金属酶进行检测,根据CLSI标准进行判读。结果临床标本主要以痰标本为主,分离率为71.1%,其次是伤口分泌物和脓汁,97株铜绿假单胞菌中产AmpC酶47株(48.5%),单产ESBLs酶菌株21株(21.6%),同时产ESBLs酶和AmpC酶菌株16株(16.4%),产金属酶的菌株9株(9.28%),产AmpC酶菌株检出率最高。讨论多重耐药铜绿假单胞菌以产AmpC酶为主,对亚胺培南、阿米卡星、环丙沙星敏感率较高,临床应根据药敏试验结果,合理选用抗生素,减少耐药菌株产生和控制医院感染。     

铜绿假单胞菌对碳青酶烯类抗菌药物的耐药性分析

目的通过分析铜绿假单胞菌感染患者的临床资料及细菌培养结果等,分析铜绿假单胞菌对碳青酶烯类抗菌药物的耐药性。方法选择160例铜绿假单胞菌感染患者为研究对象,首先对对菌株进行耐药性实验检查。抗菌药卡包括美洛培南（MEM）、亚胺培南（IMI）、头孢他啶（CAZ）、庆大霉素（GEN）、阿米卡星（AK）、环丙沙星（CIP）、氨曲南（ATM）、左氧氟沙星（LEV）、美洛西林（MEZ）、氯霉素（CMP）、哌拉西彬他唑巴坦（TZP）和头孢哌酮／舒巴坦（SCF）。以亚胺培南（IMI）和头孢他啶（CAZ）为底物,对金属β-内酰胺酶表型进行筛选。结果铜绿假单胞菌对CMP耐药率最高,为93．75％。对MEM耐药率最低,为18．13％。铜绿假单胞菌对美洛培南敏感率为81．88％,显著高于亚胺培南的敏感率61．88％,差异有统计学意义（X2=4．34、4．34,均P〈0．05）。美洛培南敏感铜绿假单胞杆菌MIC值≤1μg／mL菌株比例为76．9％,显著高于亚胺培南,MIC值2～4μg／mL菌株比例为23．1％,显著低于亚胺培南,差异具有统计学意义（X。=5．43、5．43,均P〈0．05）。32株铜绿假单胞杆菌金属β-内酰胺酶阳性率为19．4％。以CAZ为底物阳性11例,以IMI为底物阳性21例。结论铜绿假单胞杆菌对多种抗生素耐药,而对美洛培南敏感性较高,耐药菌株金属β-内酰胺酶表达率高。     

老年患者下呼吸道铜绿假单胞菌感染临床分布与耐药性分析

目的:分析老年患者下呼吸道铜绿假单胞菌感染临床分布与耐药性。方法:搜集2011年6月至2013年6月我院老年下呼吸道感染住院患者,分离培养出铜绿假单胞菌菌株痰标本156份,用VITEK2-Compact全自动细菌鉴定及药敏分析系统对临床标本中分离的156株铜绿假单胞菌进行鉴定,并采用琼脂扩散法进行体外药敏试验,依据美国临床实验室标准化协会(CLSI)最新折点判读结果。结果:非多重耐药(MDR)铜绿假单胞菌临床分离株对头孢噻肟、磺胺甲噁唑/甲氧苄啶耐药性最高,耐药率达70%以上;对亚胺培南、美罗培南、氨曲南和头孢哌酮/舒巴坦、头孢他啶、哌拉西林/舒巴坦、阿米卡星的耐药率均在20%以内,其中亚胺培南、美罗培南敏感性均达到100%。而MDR菌株对哌拉西林、头孢噻肟、庆大霉素、环丙沙星、妥布霉素、磺胺甲噁唑/甲氧苄啶高度耐药,耐药率达100%,对哌拉西林/他唑巴坦、头孢吡肟、阿米卡星耐药率高达60%以上,对亚胺培南、美罗培南、氨曲南依旧敏感性较好,耐药率均低于20%。结论:亚胺培南、美罗培南对铜绿假单胞菌有较好的敏感性,可作为老年患者重症下呼吸道铜绿假单胞菌感染治疗的首选药物,如MDR铜绿假单胞菌感染,可联合用药。在联合用药的同时应当加强医院的抗生素合理使用,规范临床用药。     

2018—2020年郑州市第七人民医院血流感染分离菌的分布及耐药性分析

目的 了解血流感染分离菌的分布及耐药特征,为临床防治血流感染提供指导和依据。方法 收集2018年1月—2020年12月郑州市第七人民医院血培养分离的非重复菌株,采用WHONET5.6软件统计菌株的分布及耐药特征。结果 共分离546株菌株,革兰阴性菌302株（55.31%）,革兰阳性菌220株（40.29%）,真菌24株（4.40%）。前6位分离菌依次为凝固酶阴性葡萄球菌（CNS,23.44%）、大肠埃希菌（18.68%）、肺炎克雷伯菌（14.84%）、金黄色葡萄球菌（6.04%）、鲍曼不动杆菌（4.21%）和铜绿假单胞菌（3.85%）。大肠埃希菌对碳青霉烯类最敏感,肺炎克雷菌碳对美罗培南和亚胺培南的耐药率分别为30.86%和35.80%,鲍曼不动杆菌耐药较严重,耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）和耐甲氧西林金黄色葡萄球菌（MRSA）的检出率分别为72.66%、42.42%,未发现利奈唑胺和万古霉素耐药的葡萄球菌。结论 革兰阴性菌是医院血流感染的主要致病菌,细菌耐药情况复杂,临床要根据药敏结果合理选择抗菌药物。     

老年患者下呼吸道感染革兰阴性杆菌分布及耐药性分析

目的:观察老年患者下呼吸道革兰阴性杆菌感染常见病原菌的分布及耐药状况.方法:对我院老年患者痰液中分离出的186株革兰阴性杆菌选用15种常用抗生索进行药敏试验.结果:分离出的186株革兰阴性杆菌,主要为:铜绿假单胞菌37株,占19.89%,肺炎克雷伯菌55株,占29.57%,鲍曼不动杆菌18株,占19.9%,阴沟肠杆菌16株,占8.60%,大肠埃希菌34株,占18.28%,嗜麦芽寡养单胞菌9株,占4.84%,其他革兰阴性杆菌17株,占9.14%;耐药性分析显示,革兰阴性杆菌对临床常用抗生素的耐药率最低为亚胺培南,最高为氨苄西林,大部分细菌呈多重耐药.结论:老年患者下呼吸道革兰阴性菌耐药谱广,多重耐药严重.     

氮离子注入法选育春雷霉素高产菌株和生产发酵

目的以氮离子束注入法对春雷霉素产生菌进行诱变育种,获得高产菌株。方法以小金色链霉菌(Streptomyces microaureus)US17为出发菌株,采用不同剂量的氮离子注入法处理该菌株,经过摇瓶初筛、复筛和上罐发酵,确定生产性状优良的菌种。结果经过诱变处理和筛选后,获得4株高产菌株。其中K1999.2010S247菌株摇瓶效价达到27 546mg·L-1。经25吨罐生产验证,平均发酵效价比原工业生产菌株提高了5.44%,组分含量质量分数提高了4.5%。结论采用离子束注入法对春雷霉素产生菌诱变育种效果显著,所获得高产菌株发酵效价高、组分含量高,产生巨大的经济效益,适合工业生产发酵使用。     

昆明地区耐碳青霉烯类抗生素铜绿假单胞菌的分子流行病学特点及耐药特征分析

目的 研究耐碳青霉烯类抗生素铜绿假单胞菌分子流行病学规律及耐药机制,为临床预防和治疗铜绿假单胞菌的感染提供理论依据。方法 对多中心收集的耐碳青霉烯类抗生素铜绿假单胞菌(carbapenems-resistant Pseudomonas aeruginosa,CRPA)开展多位点序列分型(multilocus sequence typing,MLST)和遗传信息研究,并对碳青霉烯酶基因与外膜孔蛋白OprD编码基因进行序列分析。结果 多位点序列分型方法将81株CRPA分为36个ST型,总体以ST3390(41.98%,34/81)为主,其中有5种为新发现的ST型别;CRPA菌株中碳青霉烯酶基因的检出率较高(65.43%,53/81),尿液标本检出率最高(80.00%,28/35),其中IMP、VIM和NDM型碳青霉烯酶基因检出率分别为37.04%、27.16%和1.23%,未检测到KPC、GES、SPM和OXA-40型碳青霉烯酶基因;oprD基因的序列比对分析发现,高达96.29%(78/81)CRPA临床分离株发生了各种类型的突变,以单个或者多个碱基的插入或缺失为主(76.54%,62/...     

2005～2006年华西院内感染革兰阴性杆菌耐药性比较

比较2005～2006年华西医院病房送检标本中分离的革兰阴性杆菌各100株的耐药情况变化,采用E-test法测定对10种抗生素的最低抑菌浓度(MIC值).2005年分离率较高的细菌分别是大肠埃希菌(39%),不动杆菌属细菌(17%)、肠杆菌属细菌(17%)、铜绿假单胞菌(15%)和克雷伯菌属细菌(12%),2006年分离率较高的细菌分别是大肠埃希菌(34%)、铜绿假单胞菌(24%)、不动杆菌属细菌(17%)、克雷伯菌属细菌(13%)和肠杆菌属细菌(10%);铜绿假单胞菌的分离率较2005年有较显著的增加.     

田菁及其与硫酸铵混合施用时水稻对肥料氮和土壤...

应用标记15_M的田菁和硫铵进行一季水稻盆栽试验的结果表明,1.田菁和硫铵单独施用,田菁氨素的17.6％和41.8％分别为稻秆和谷粒利用,硫铵氨素的分别为15.1％和29.0％。这两种肥料氮在谷粒中分布的比例较大,稻杆和谷粒对田菁氨的利用率都高于硫铵氮.2.施用硫铵有促进水稻吸收土壤氨素的作用,比不施氨对照增加71.8％;相反,施用田菁减弱了水稻对土壤氨的吸收,比对照减少37.1％。3.田菁和硫铵混合施用,除了可使水稻对田菁氨的吸收增加(5.2％)。对硫铵氨的吸收减少(5.3％)外,亦有促进水稻增加吸收土壤氨素的作用,4.与硫铵单独施用的结果相比,这两种肥料混合施用,可以在消耗较少量土壤氨素的基础上,更好地维持水稻生长所需的氨营养供应。     

Antimicrobial susceptibility of Pseudomonas aeruginosa isolated in Fukushima Prefecture

We investigated the susceptibility of Pseudomonas aeruginosa (isolated from the sputum of patients with respiratory infection in 4 medical institutions in Fukushima Prefecture) to 8 beta-lactam antibiotics including three carbapenems and relationships among MICs of antibiotics tested. The MIC90 values for a total of 216 strains were 6.25 micrograms/ml for meropenem, 12.5 micrograms/ml for imipenem and ceftazidime, 25 micrograms/ml for panipenem and cefsulodin, 50 micrograms/ml for cefpirome and over than 200 micrograms/ml for cefoperazone and piperacillin. The frequency of resistance of these strains to each antibiotic was as follows: The resistant strains were 19 (8.8%) for meropenem, 34 (15.7%) for imipenem and ceftazidime, 50 (23.1%) for cefsulodin, 72 (33.3%) for panipenem, 76 (35.2%) for piperacillin and 90 (41.7%) for cefpirome. Eighteen strains (18.3%) of 19 meropenem resitant straisn were resistant to imipenem and panipenem, but 16 strains of the 34 imipenem-resistant strains and 54 strains of the 72 panipenem-resistant strains were susceptible to meropenem. In investigation of isolation of multi-resistant Pseudomonas aeruginosa, the susceptibility of strains tested to 7 antibiotics except cefoperazone was as follows: The strains susceptible to all the 7 antibiotics were 92 strains (42.6%), and 33 strains (15.2%) were resistant to 2 antibiotics, 31 strains (14.4%) were resistant to 1 antibiotic, 21 strains (9.7%) were resistant to 3 antibiotics, 13 strains (6.0%) were resistant to 5 antibiotics, 9 (4.2%) were resistant to 4 and 7 antibiotics, and 8 strains (3.7%) were reistant to 6 antibiotics. Since the emergence of these multi-resistant strains is closely related to frequent use of antibiotics for nosocomial infections, special attention should be paid to the antimicrobial susceptibility of Pseudomonas aeruginosa and the situation of antibiotic resistant strains.     

OXA-50型碳青霉烯酶基因在铜绿假单胞菌中分布的初步研究

目的研究铜绿假单胞菌(Pseudomonas aeruginosa,PA)对碳青霉烯类抗生素耐药的分子机制。方法收集非重复34株铜绿假单胞菌临床株,PCR扩增blaOXA-50基因、测序、在GenBank上比对、提取质粒DNA、对该基因进行PCR扩增。结果PCR检测出34株铜绿假单胞菌中有15株含OXA-50型基因,其中30株耐亚胺培南的铜绿假单胞菌中有12株阳性,4株敏感菌中亦有3株阳性;随机选取1株阳性菌PCR产物送测序,测序结果在GenBank上进行blast比对,显示有两个突变点;blaOXA-50基因扩增阳性的15株铜绿假单胞菌,提取质粒DNA扩增该基因,结果为阴性。结论本次实验检测了34株铜绿假单胞菌临床株,OXA-50型基因的检出率为44.10%,其中1株发现有两个位点突变;检测到的blaOXA-50编码基因位于染色体上。     

不常见非发酵菌对常见抗菌药物敏感性分析

目的了解临床分离的伯克霍尔德菌属、金色杆菌属、产碱杆菌属等不常见非发酵菌的耐药性。方法从2004年~2006年临床各种标本中分离到的不常见革兰阴性杆菌用V ITEK-2全自动微生物分析仪进行检测鉴定,药物敏感性试验采用纸片扩散法。数据分析采用WHONET 5.4软件进行处理、统计和分析。结果两年中中山大学第一附属医院共收集患者首次分离株118株,其中伯克霍尔德菌属47株(其中洋葱伯克霍尔德菌41株,皮氏伯克霍尔德菌6株),金色杆菌属44株(其中脑膜脓毒性金黄杆菌17株,产吲哚金黄杆菌23株),产碱杆菌属27株(其中粪产碱杆菌13株,木糖氧化无色杆菌12株)。96.6%的菌株来源于痰标本。对伯克霍尔德菌属有较强体外抗菌活性的依次为:复方磺胺甲口恶唑(87.2%)、哌拉西林/三唑巴坦(87.0%)、左氧氟沙星(85.3%)、头孢吡肟(83.0%)、头孢他啶(78.6%)和头孢哌酮/舒巴坦(78.3%)。对金色杆菌属有较强体外抗菌活性以复方磺胺甲口恶唑(87.5%)最高。对产碱杆菌属敏感性较高的药物分别为头孢哌酮/舒巴坦(84.6%)和美罗培南(77.8%)。结论头孢哌酮/舒巴坦对三种非发酵菌都有较高体外抗菌活性。常规实验室鉴定方法易将三种菌相互混淆,甚至与氧化酶阴性的非发酵菌混淆,这可能是造成各地报道药敏结果差异的原因之一。     

Comparative in vitro activity of ciprofloxacin against aerobic and anaerobic bacteria from clinical isolates

1-Cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-piperazin-1- ylquinoline-3-carboxylic acid (ciprofloxacin, Bay o 9867, Ciprobay) is a broad spectrum antibiotic of the 4-quinolone group. It possesses a bactericidal effect attributable to the property of DNA-gyrase inhibition. The antimicrobial action comprises all grampositive strains (including Streptococcus faecalis) and gramnegative strains (including Pseudomonas aeruginosa and Serratia spp.), as well as Bacteroides fragilis and other Bacteroides species. In this comparative study the antimicrobial effect of ciprofloxacin was tested against 665 gramnegative, 412 grampositive and 274 anaerobic strains from fresh clinical isolates and compared with that of other frequently used antibiotics. The minimum inhibitory concentrations (MIC) were determined by means of a serial dilution test with micro standard plates. Within the group of gramnegative strains, ciprofloxacin was the most active antibiotic with an MIC90 of 0.12 mg/l to 0.5 mg/l for most isolates. Ciprofloxacin shows a broad spectrum of activity against gramnegative pathogenic bacteria including Escherichia coli, Klebsiella spp., Citrobacter spp., Enterobacter spp., Serratia spp. and Acinetobacter spp., and also covers resistant strains of Pseudomonas aeruginosa and Alcaligenes faecalis. Ciprofloxacin also shows a high inhibiting activity against grampositive strains (Staphylococci, Enterococci) and anaerobic pathogens.     

Identity and antibiotic susceptibility of enterobacterial flora of salad vegetables.

The enterobacterial flora from carrots (organic and non-organic) and salad vegetables has been identified and antibiotic susceptibilities determined. Pseudomonas fluorescens and Pantoea (formerly Enterobacter) agglomerans were the species most commonly found; the former was usually resistant to at least six of the antibiotics under test. Rahnella aquatilis (often producing beta-lactamase) was also found in carrots. There were no clear differences in flora from organic and non-organic carrots. Thus, uncooked vegetables are a potential source of highly resistant opportunistic pathogens.     

Differential sensitivity of five cyanobacterial strains to ammonium toxicity and its inhibitory mechanism on the photosynthesis of rice-field cyanobacterium Ge-Xian-Mi (Nostoc)

Effects of two fertilizers, NH(4)Cl and KCl, on the growth of the edible cyanobacterium Ge-Xian-Mi (Nostoc) and four other cyanobacterial strains were compared at pH 8.3+/-0.2 and 25 degrees C. Their growth was decreased by at least 65% at 10mmolL(-1) NH(4)Cl but no inhibitory effect was observed at the same level of KCl. Meanwhile, the strains exhibited a great variation of sensitivity to NH(4)(+) toxicity in the order: Ge-Xian-Mi>Anabaena azotica FACHB 118>Microcystis aeruginosa FACHB 905>M. aeruginosa FACHB 315>Synechococcus FACHB 805. The 96-h EC(50) value for relative growth rate with regard to NH(4)(+) for Ge-Xian-Mi was 1.105mmolL(-1), which was much less than the NH(4)(+) concentration in many agricultural soils (2-20mmolL(-1)). This indicated that the use of ammonium as nitrogen fertilizer was responsible for the reduced resource of Ge-Xian-Mi in the paddy field. After 96h exposure to 1mmolL(-1) NH(4)Cl, the photosynthetic rate, F(v)/F(m) value, saturating irradiance for photosynthesis and PSII activity of Ge-Xian-Mi colonies were remarkably decreased. The chlorophyll synthesis of Ge-Xian-Mi was more sensitive to NH(4)(+) toxicity than phycobiliproteins. Thus, the functional absorption cross section of Ge-Xian-Mi PSII was increased markedly at NH(4)Cl levels >/=1mmolL(-1) and the electron transport on the acceptor side of PSII was significantly accelerated by NH(4)Cl addition >/=3mmolL(-1). Dark respiration of Ge-Xian-Mi was significantly increased by 246% and 384% at 5 and 10mmolL(-1) NH(4)Cl, respectively. The rapid fluorescence rise kinetics indicated that the oxygen-evolving complex of PSII was the inhibitory site of NH(4)(+).     

Adrenal cortex adenylate cyclase

Summary Speci fic binding sites for 5-guanylyl-imidodiphosphate [Gpp(NH)p] have been identified in a partially purified plasma membrane fraction from bovine adrenal cortex. The apparent affinity of Gpp(NH)p at 30° C was 12 M^–1 and the concentration of binding sites was 100 pmoles per mg of protein. Binding of Gpp (NH)p is inhibited by Mn²⁺ > Mg²⁺ Ca²⁺ and enhanced by low concentrations of the chelators ethylenediamino-tetraacetic acid (EDTA) and ethylene glycolbis-(-aminoethylether)-N,N'-tetraacetic acid (EGTA). High concentrations of EDTA are inhibitory and at 2.5 mM EDTA binding of Gpp(NH)p is only 10% of that observed in the absence of the chelator. The bound labeled GTP analogue exchanged only slowly with the unlabeled nucleotide after a steady state has been reached. EDTA also releases the bound labeled Gpp(NH)p from its binding sites. The slow dissociation of Gpp(NH)p can explain the persistent activation of adenylate cyclase observed after pretreatment of bovine adrenal cortex plasma membranes with Gpp(NH)p and subsequent washing.It is suggested that at least parts of these binding sites are identical to the sites identified earlier as regulatory sites for angiotensin high-affinity receptors (Glossmann et al., 1974a) and for ACTH-stimulated cyclase (Glossmann and Gips, 1974).     

Antibacterial activity of norfloxacin against 1700 relatively resistant clinical isolates

A total of 1724 clinical isolates from patients with different infections were tested in vitro to determine their susceptibility to norfloxacin. Antibacterial activity of norfloxacin was compared with other drugs that were commonly used in the hospital. Of the 919 strains of Enterobacteriaceae tested, all except four isolates of Enterobacter, two of Serratia and one of Proteus were susceptible to norfloxacin. Ninety-five percent of the 199 strains of Pseudomonas aeruginosa were also inhibited by this quinolone. Brucella melitensis (81 strains) was completely susceptible to norfloxacin. All the 250 isolates of Staphylococcus aureus and coagulase-negative staphylococci were also sensitive to norfloxacin. Pseudomonads other than P.aeruginosa, Acinetobacter/Alcaligenes and group D streptococci were less sensitive to norfloxacin, with 56%, 57% and 20% respectively being inhibited by this antimicrobial agent.