洋葱伯克霍尔德菌临床分离和耐药性监测

/他唑巴坦和复方新诺明敏感.来自ICU的洋葱伯克霍尔德菌耐药更强.结论 洋葱伯克霍尔德菌耐药及多药耐药性严重,应引起广泛关注,尤其是中心ICU,治疗上可选用哌拉西林/他唑巴坦.     

进口化妆品检出洋葱伯克霍尔德菌及其意义

从进口化妆品中检出洋葱伯克霍尔德菌,为化妆品标准中微生物检验项目的制定提供参考,为临床医学和流行病学提供感染源依据。     

土壤中产脂肪酶洋葱伯克霍尔德菌的分离与鉴定

洋葱伯克霍尔德菌(Burkholderia cepacia)在生物防治、生物降解等农业领域有着广泛的应用,它产生的脂肪酶则在有机合成、精细化工等领域潜力巨大。采用改良的TB-T平板筛选法从土壤中初步筛选出300株洋葱伯克霍尔德菌,然后用脂肪酶活性检测平板对300株菌进行筛选,最终获得6株脂肪酶产量高的菌,通过发酵发现6株菌均有较好的产脂肪酶能力。随后通过16S rDNA比对的方法将6株全部鉴定为B.cepacia。在此基础上,采用HaeⅢ-recA RFLP和基因种特异性PCR对6株菌进行了基因种鉴定,结果表明JWT16、G63YL、WJ158和JWT137属于Burkholderia cenocepacia菌,JWP9属于Burkhold-eria vietnamiensis,JWT267则属于Burkholderia multivorans。     

重症监护病房洋葱伯克霍尔德菌医院感染的特征及耐药性分析

目的了解重症监护病房（ICU）洋葱伯克霍尔德菌引起医院感染的特征及耐药情况,为临床治疗及控制该菌的暴发流行提供实验依据。方法常规方法对我院2003年1月至2007年10月ICU的病人的各种临床标本进行分离培养,细菌鉴定及药敏试验采用全自动微生物鉴定仪VITEK-2进行。结果引起ICU医院感染的洋葱伯克霍尔德菌共有99例,感染以肺部感染为主,对临床常用的多种抗菌药物表现交叉耐药,对头孢匹肟、亚胺培南、哌拉西林、阿米卡星、庆大霉素的敏感率较差在50．0％以下;对环丙沙星、左氧氟沙星、头孢他啶、氨曲南、哌拉西林／他唑巴坦、美诺培南和复方新诺明的敏感率较高,分别为82．8％、87．9％、91．9％、72．7％、55．6％、62．6％和100．0％。结论引起ICU医院感染的洋葱伯克霍尔德菌具有多重耐药性,临床治疗时应根据药敏结果选用抗菌药物。     

洋葱伯克霍尔德菌外膜蛋白双向电泳的建立与优化

目的:洋葱伯克霍尔德菌外膜蛋门的分离及双向电泳图谱的建立和优化.方法:用月桂酰基氯酸钠法提取外膜蛋白,以同相pH梯度为第一向和SDS-PAGE为第二向进行双向电泳,对裂解液成分,IPG胶条的pH和凝胶染色方法等进行优化.结果:获得外膜蛋白浓度为2.87μg/μl;最佳裂解液成分为:7mol/L尿素,2mol/L硫脲,4%Chaps,2%pharmalyte,65 mmol/L DTT,0.5%Triton X-100,10mmol/L Tris.结论:提取的外膜蛋白满足双向电泳条件;获得理想的外膜蛋白双向电泳图谱用于后续实验中.     

儿童医院感染洋葱伯克霍尔德菌三年临床分布特征调查

目的调查三年来儿童医院感染洋葱伯克霍尔德菌的临床分布特点及耐药情况,指导临床合理用药。方法2010年1月-2012年12月住院患儿送检标本采用VITEK-32全自动细菌鉴定仪进行细菌鉴定,药敏试验采用Kirby—Bauer法。结果三年分离到洋葱伯克霍尔德菌分别为28株、36株和51株,共¨5株,呈逐年上升趋势;其来源主要分布在儿童ICU和新生儿病房,以引起儿童呼吸道感染为主要症状;药敏结果显示替卡西林／克拉维酸、庆大霉素、氨苄西林／舒巴坦等耐药率均逐年升高;对哌拉西林／他唑巴坦、头孢他啶和复方新诺明敏感性高。结论儿童医院感染洋葱伯克霍尔德菌呈逐年上升趋势,因其是一种多重耐药菌,天然耐多种抗菌药物,临床监测其分布状况和耐药性具有重要意义。     

洋葱伯克霍尔德菌致恶性肿瘤患者医院获得性感染的耐药性分析

目的分析我院恶性肿瘤患者医院获得性感染洋葱伯克霍尔德菌的临床特点及对常用抗菌药物的耐药性,为临床合理治疗提供依据。方法回顾性分析2011年1月至2013年12月,从我院恶性肿瘤感染患者送检的细菌培养标本;细菌鉴定用美国BD公司phoenix-100全自动细菌鉴定药敏系统,药敏试验采用纸片法,同时使用WHONET 5.6软件对相关资料进行统计。结果从检测部位分析主要分布在下呼吸道（74.1%）,其次为血液（9.4%）;药敏试验表明139株洋葱伯克霍尔德菌对米诺环素、氯霉素、美罗培南、头孢他啶和头孢哌酮/舒巴坦仍较敏感,可作为临床治疗洋葱伯克霍尔德菌感染的首选药物,其余15种抗菌药物的耐药率高达30.0%~100%。结论洋葱伯克霍尔德菌在恶性肿瘤患者中的耐药现象非常严重,临床应引起高度关注,及早进行微生物学检测,并根据药敏试验结果合理选用抗菌药物。     

2004～2008年洋葱伯克霍尔德菌临床分布和耐药性分析

目的 了解2004年至2008年我院临床分离的洋葱伯克霍尔德菌的标本来源、临床分布和耐药性.方法 采用API staph 鉴定系统和K-B琼脂扩散法,对分离到的55株洋葱伯克霍尔德菌进行鉴定和药敏试验.结果 2004年至2008年共分离出55株洋葱伯克霍尔德菌, 标本来源以痰标本最多(90.91%,50/55),科室分布以ICU最多(60%,33/55),其次为呼吸内科(18.18%,10/55).药敏结果 显示,对多数抗菌药物的耐药率较高,只对美罗培南、哌拉西林/他唑巴坦和亚胺培南的耐药率最低,分别为29.17%、33.33%和39.62%.结论 药敏结果 显示,洋葱伯克霍尔德菌具有高度和多重耐药性,临床抗感染治疗应根据药敏试验结果 选用敏感药物.     

重症监护病房洋葱伯克霍尔德菌肺部感染及耐药性监测

目的 探讨重症监护病房(ICU)洋葱伯克霍尔德菌肺部感染的临床特点及其耐药情况,为临床合理用药提供参考.方法 对2010年10月至2011年10月在ICU住院期间,患者肺部感染洋葱伯克霍尔德菌耐药情况进行回顾性分析.结果 肺部感染患者共检出34株洋葱伯克霍尔德菌,占全部病原菌的1.85％.19种抗菌药物药敏试验结果显示除美罗培南、复方磺胺甲基异噁唑、米诺环素的抑菌活性较高外,其余16种抗菌药物的耐药率高达73.5％～100.0％.结论 洋葱伯克霍尔德菌具有多重耐药性,治疗难度大,应引起足够重视,临床应根据药敏试验结果合理选用抗菌药物.     

1997～2002年洋葱伯克霍尔德菌的临床分离与耐药性变迁

目的了解本地区洋葱伯克霍尔德菌在临床的分离与耐药性变迁情况,以利于临床抗感染的预防与治疗.方法用WHONET5软件统计分析浙江省人民医院1997～2002年洋葱伯克霍尔德菌临床分离菌株在各病区、样本中的分布及耐药性的变迁情况.结果分离率从1977年的0.11%上升到2002年的0.37%;6年中以监护病区分离菌株最高占总分离菌株的48.4%,其次为呼吸科病区占10.9%;在送检样本中以呼吸道标本分离菌株数最高占总分离数的66.1%(痰液 咽拭子),其次为血液占10.4%.对26种抗生素的耐药性分析示,多数抗菌药物其耐药性均大于50%;小于50%只有6种,哌拉西林或他唑巴坦(40.5%～42.9%),头孢哌酮或舒巴坦(33.%～49.1%),头孢吡肟(40.1%～46.%);环丙沙星(28.6%～46.2%);左氟沙星(33.3%～46.4%),复方新诺明(28.6%～42.9%).结论洋葱伯克霍尔德菌在临床的分离率在增加,已成为医院内感染的主要病原菌之一,该菌对多数抗菌药物具有较高耐药性,且有不断增加趋势,临床抗感染治疗应以分离菌株的体外抗菌药物敏感性为依据.     

洋葱伯克氏菌基因型的鉴定及其在苜蓿模型上的毒力分析

[目的]证实来自我国农业和医院环境中部分洋葱伯克氏菌的基因型并通过苜蓿植物模型探测不同基因型对人体的可能毒力.[方法]采用洋葱伯克氏菌基因型的PCR特异性扩增技术对来源于根围、土壤和医院中的57株洋葱伯克氏菌进行了基因型的鉴定,并利用苜蓿植物模型对这些基因型菌株进行了毒力探测.[结果]获得4种不同的基因型,包括基因型Ⅰ、ⅢA、ⅢB、Ⅴ和Ⅸ.来源于医院的基因型Ⅰ和ⅢA菌株以及根围的基因型ⅢB菌株均对苜蓿幼苗有较强的毒力,其对苜蓿幼苗的平均发病率分别达到69%、68%和55%,与农田环境中基因型Ⅴ和Ⅸ对苜蓿幼苗的发病率相比,表现出显著的差异性.[结论]农田环境中洋葱伯克菌的基因型在苜蓿模型上的毒力差异大,根围的基因型ⅢB菌株对苜蓿幼苗具有强毒力,其毒力程度接近于医院致病基因型ⅢA菌.     

Defining potential targets for immunotherapy in Burkholderia cepacia infection

Abstract Burkholderia cepacia has become a serious source of infection in patients with cystic fibrosis. Antibiotic therapy is difficult as the bacteria are intrinsically resistant to most antibiotics. The present study compared the antibody response by immunoblot of 50 negative control sera, 22 patients with cystic fibrosis and no evidence of B. cepacia , 9 clinically well patients with cystic fibrosis colonised by B. cepacia and 5 patients with cystic fibrosis and deteriorating or fatal B. cepacia infection. Nineteen antigenic bands varying in apparent molecular weights from 19 to 170 kDa were identified. Two bands at 19 and 21 kDa were only present when the organism was grown in an iron-deficient medium. The band at 30 kDa was identified as a porin and the possession of IgG antibody carried a statistically significant ( P = 0.00003) better prognosis. This antigen was thus a potential target for immunotherapy.     

Immobilization of Burkholderia cepacia in polyurethane-based foams: embedding efficiency and effect on bacterial activity

Immobilization of the trichloroethylene-degrading bacterium Burkholderia cepacia was evaluated using hydrophilic polyurethane foam. The influence of several foam formulation parameters upon cell retention was examined. Surfactant type was a major determinant of retention; a lecithin-based compound retained more cells than pluronic- or silicone-based surfactants. Excessive amounts of surfactant led to increased washout of bacteria. Increasing the biomass concentration in the foam from 4.8 to 10.5% dry weight per wet weight of foam resulted in fewer cells being washed out. Embedding at reduced temperature did not significantly affect retention, while the use of a silane binding agent gave inconsistent results. The optimal formulation retained all but 0.2% of total embedded cells during passage of 2 L of water through columns containing 2 g of foam. All foam formulations tested reduced the culturability of embedded cells by several orders of magnitude, but O₂ consumption and CO₂ evolution rates of embedded cells were never less than 50% of those of free cells. Nutrient amendments stimulated an increase in cell volume and ribosomal activity in immobilized cells as indicated by hybridization studies using fluorescently labeled ribosomal probes. These results indicate that, although immobilized cells were mostly nonculturable, they were metabolically active and thus could be used for biodegradation of toxic compounds. Received 23 December 1996/ Accepted in revised form 13 March 1997     

Serum sensitivity of Burkholderia (Pseudomonas) cepacia isolates from patients with cystic fibrosis

Abstract Bacterial strains which are sensitive to the bactericidal activity of serum are generally considered to be less virulent than serum-resistant strains and are seldom associated with bacteraemia. Burkholderia ( Pseudomonas ) cepacia is an important pathogen in cystic fibrosis and is associated with rapid fatal pulmonary decline and bacteraemia in 20% of colonised patients. In this study 19 isolates of B. cepacia expressing either rough or smooth LPS were investigated to determine the degree of serum sensitivity. Strains expressing rough-LPS were serum-sensitive: these included a highly transmissible strain of B. cepacia isolated from approximately 50 cystic fibrosis patients attending various U.K. regional centres and associated with cases of bacteraemia.     

Exopolysaccharide production by mucoid and non-mucoid strains of Burkholderia cepacia

Thirteen strains of Burkholderia cepacia from various origins with mucoid and non-mucoid phenotypes were assayed for exopolysaccharide (EPS) production. The EPS were characterized by glycosyl composition analysis and examination of the products resulting from lithium-ethylenediamine and Smith degradations. The results showed that all strains, including the non-mucoid strains, were able to produce EPS exhibiting the same structural features, i.e. presence of one rhamnosyl, three galactosyl, one mannosyl, one glucosyl and one glucuronosyl residues, suggesting that this EPS is representative of the B. cepacia species.     

Isolation and characterization of a cyanide-utilizing Burkholderia cepacia strain

A bacterium that utilizes cyanide as a nitrogen source was isolated from soil after enrichment in a liquid medium containing potassium cyanide (10mM) and glucose (1.0%, w/v). The strain could tolerate and grow in potassium cyanide at concentrations of up to 25mM. It could also utilize potassium cyanate, potassium thiocyanate, linamarin and a range of aliphatic and aromatic nitriles. The isolate was tentatively identified as Burkholderia cepacia strain C-3. Ammonia and formic acid were found in the culture supernatant of the strain grown on fructose and potassium cyanide, no formamide was detected, suggesting a hydrolytic pathway for the degradation of cyanide. The cyanide-degrading activity was higher in early and the stationary phase cells. Crude cell extracts of strain C-3 grown on nutrient broth exhibited cyanide-degrading activity. The characteristics of strain C-3 suggest that it would be useful in the bioremediation of cyanide-containing waste.     

Diverse pathogenicity of Burkholderia cepacia complex strains in the Caenorhabditis elegans host model

A fast screening method was developed to assess the pathogenicity of a diverse collection of environmental and clinical Burkholderia cepacia complex isolates in the nematode Caenorhabditis elegans. The method was validated by comparison with the standard slow-killing assay. We observed that the pathogenicity of B. cepacia complex isolates in C. elegans was strain-dependent but species-independent. The wide range of observed pathogenic phenotypes agrees with the high degree of phenotypic variation among species of the B. cepacia complex and suggests that the taxonomic classification of a given strain within the complex cannot predict pathogenicity.