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Occurrence of K1 and K2 serotypes and genotypic characteristics of extended spectrumβ-lactamases-producing Klebsiella pneumoniae isolated from selected hospitals in Malaysia
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作者 Nurul Syazrah Anuar Hazmin Hazman +5 位作者 Sharven Raj Jeyakumar Mohd Nasir Mohd Desa Hasni Idayu Saidi Siti Norbaya Masri Nur Afiza Aziz Nurshahira Sulaiman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期30-38,共9页
Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selecte... Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selected hospitals in Malaysia.Methods:A total of 192 K.pneumoniae isolates were collected and subjected to antibiotic susceptibility,hypermucoviscosity test and multiplex PCR to detect the presence of K1-and K2-serotype associated genes.Multilocus sequence typing(MLST)was performed on ESBL-producing K.pneumoniae isolates presented with K1 and K2 serotypes,followed by phylogenetic analysis.Results:A total of 87 out of 192(45.3%)of the K.pneumoniae isolates collected were ESBL producers.However,only 8.3%(16/192)and 10.9%(21/192)of the total isolates were detected to carry K1-and K2-serotype associated genes,respectively.Statistical analysis showed that K1 and K2 capsular serotypes were not significantly associated with ESBL phenotype(P=0.196).However,they were significantly associated with hypervirulent,as demonstrated by the positive string test(P<0.001).MLST analysis revealed that ST23 as the predominant sequence type(ST)in the K1 serotype,while the ST in the K2 serotype is more diverse.Conclusions:Although the occurrence of ESBL-producing isolates among the hypervirulent strains was low,their coexistence warrants the need for continuous surveillance.MLST showed that these isolates were genetically heterogeneous. 展开更多
关键词 Extended spectrumβ-lactamases Klebsiella pneumoniae Capsular serotypes GENOTYPIC
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Evaluation of Disk Potentiation Test (DPT) and Double Disk Synergy Test (DDST) for The Detection of Metallo-β-Lactamases (MBLs) in Clinical Isolates of Bangladesh
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作者 Sumon Kumar Das Afzal Sheikh +4 位作者 Nikhat Ara Suma Mita Biswas Abhinandan Chowdhury Fatimah Az Zahra Chaman Ara Keya 《Advances in Infectious Diseases》 2023年第4期609-626,共18页
Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determin... Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determine a suitable method to promptly detect MBL-producing gram-negative bacteria. Methods: A total of 103 gram-negative bacteria were identified from various clinical samples at a tertiary care hospital in Dhaka city. MBL producers were detected by two phenotypic methods, the Disk Potentiation Test (DPT) and the Double Disk Synergy Test (DDST) based on β-lactam chelator combinations where EDTA/SMA has been used as an inhibitor and Imipenem, Ceftazidime as substrates. Results: 103 isolates which were identified as Escherichia coli spp, Klebsiella spp, Pseudomonas spp, Acinetobacter spp, Proteus spp, Providencia spp were found to be multidrug-resistant in antibiogram test. Isolates showed complete resistance (100%) to Imipenem, Meropenem, and Amoxiclav. The highest carbapenem-resistant etiological agents were Acinetobacter spp 40 (38.8%) followed by Pseudomonas spp 27 (26.2%), Klebsiella spp 26 (25.2%), Escherichia coli 8 (7.8%), Proteus spp 1 (1%) and Providencia spp 1 (1%). DPT method detected significantly (p = 0.000009) a higher number of MBL-producers (Imipenem with 0.5 M EDTA n = 61, 59.2% & Ceftazidime with 0.5 M EDTA n = 56, 54.4%) compared to the DDST method (Imipenem -0.5 M EDTA n = 43, 41.7%, Imipenem – SMA n = 38, 36.9% & Ceftazidime -0.5 M EDTA n = 15, 14.6%). Conclusion: Pieces of evidence suggest that DPT is a more sensitive method than DDST and could be recommended for identifying MBL-producing bacteria in Bangladeshi hospitals for the proper management of patients, to reduce time constraints and treatment costs. 展开更多
关键词 Disk Potentiation Test (DPT) Double Disk Synergy Test (DDST) Metallo-β-lactamase (MBL) Sodium Mercaptoacetate (SMA) and Ethylenediaminetetraacetic Acid (EDTA)
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Characteristics of β-Lactamase Synthesis in E. coli and K. pneumanie Strains in Nosocomial Infections
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作者 Saddraddin A. Atakishizadeh Sayyaddin A. Atakishizadeh Mahammad M. Davudov 《Advances in Microbiology》 CAS 2024年第1期25-30,共6页
Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomi... Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomial urinary tract infections, surgical site infections and pneumonia in surgical clinic were studied. ESBL synthesis were observed 38.9% of E. coli strains obtained from urine, 92.3% of strains obtained from surgical site infections, and 50% of strains obtained from sputum. ESBL synthesis were observed 37.5% of K. pneumoniae strains obtained from urine, 85.7% of strains obtained from surgical site infections, and 60% of strains obtained from sputum. Different levels of ESBL synthesize of E. coli and K. pneumoniae strains isolated from different pattern is discussed. Conclusion. ESBL synthesis is common in E. coli and K. pneumoniae strains, which cause nosocomial infections. The frequency of occurrence of ESBL s synthesis among of these strains depends on clinical forms of nosocomial infections. 展开更多
关键词 Nosocomial Infectious Agents β-lactamase Synthesis E. coli and K. pneumoniae
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Metallo-β-Lactamases:A Major Threat to Human Health 被引量:1
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作者 Emer K.Phelan Manfredi Miraula +3 位作者 Christopher Selleck David L.Ollis Gerhard Schenk Natasa Mitic 《American Journal of Molecular Biology》 2014年第3期89-104,共16页
Antibiotic resistance is one of the most significant challenges facing global healthcare. Since the 1940s, antibiotics have been used to fight infections, initially with penicillin and subsequently with various deriva... Antibiotic resistance is one of the most significant challenges facing global healthcare. Since the 1940s, antibiotics have been used to fight infections, initially with penicillin and subsequently with various derivatives including cephalosporins, carbapenams and monobactams. A common characteristic of these antibiotics is the four-memberedβ-lactam ring. Alarmingly, in recent years an increasing number of bacteria have become resistant to these antibiotics. A major strategy employed by these pathogens is to use Zn(II)-dependent enzymes, the metallo-β-lactamases (MBLs), which hydrolyse theβ-lactam ring. Clinically useful MBL inhibitors are not yet available. Consequently, MBLs remain a major threat to human health. In this review biochemical properties of MBLs are discussed, focusing in particular on the interactions between the enzymes and the functionally essential metal ions. The precise role(s) of these metal ions is still debated and may differ between different MBLs. However, since they are required for catalysis, their binding site may present an alternative target for inhibitor design. 展开更多
关键词 Antibiotic Resistance β-Lactam Antibiotics Metallo-β-lactamases Reaction Mechanism Metal Ion Binding
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Microbiologic and Clinical Comparison of Patients Harboring <i>Escherichia coli</i>Blood Isolates with and without Extended-Spectrum <i>β</i>-Lactamases
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作者 Anna Nussbaum Noriel Mariano +5 位作者 Rita Colon-Urban Rachelle A. Modeste Sadia Zahid Wehbeh Wehbeh Sorana Segal-Maurer Carl Urban 《Advances in Infectious Diseases》 2013年第1期50-54,共5页
The clinical and microbiologic characteristics of 34 patients with extended-spectrum β-lactamase (ESBL) positive E. coli isolated from blood were compared to 66 bacteremic patients with ESBL negative E. coli, from Ja... The clinical and microbiologic characteristics of 34 patients with extended-spectrum β-lactamase (ESBL) positive E. coli isolated from blood were compared to 66 bacteremic patients with ESBL negative E. coli, from January 2007 through December 2009. Of the 21 ESBL positive isolates available for PCR analysis, 13 were positive for CTX-M, 8 for TEM, 4 for SHV β-lactamases, with 6 possessing multiple enzymes. Twenty of 34 (59%) ESBL-positive and 41 of 66 (62%) ESBL-negative blood isolates were considered community-associated. All but one isolate in both groups had MICs of ≤1.0 μg/ml to meropenem. However, when compared to ESBL-negative isolates, ESBL-positive isolates were more frequently resistant to levofloxacin, trimethoprim/sulfamethoxazole and had higher MICs to gentamicin, tobramycin and piperacillin/tazobactam. The use of intravenous and urinary catheters was strongly associated with the isolation of E. coli bloodstream isolates in both groups of patients. Although hospital stay was similar in both groups, appropriate therapy was given in 87% of patients with ESBL positive vs. 98% of patients with ESBL negative isolates and mortality was greater for patients with ESBL positive isolates (26% vs. 17%). Since a large proportion of E. coli blood isolates were ESBL-positive and community-associated, carbapenems should be considered as initial empiric therapy for such infections in our locale. 展开更多
关键词 Escherichia coli Bacteremia Extended-Spectrum β-lactamases
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Unusual metallo-β-lactamases may constitute a new subgroup in this family of enzymes
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作者 Chun-Feng D.Hou Emer K.Phelan +3 位作者 Manfredi Miraula David L.Ollis Gerhard Schenk Natasa Mitic 《American Journal of Molecular Biology》 2014年第1期11-15,共5页
Metallo-β-lactamases (MBLs) are a family of Zn2+-dependent enzymes that have contributed strongly to the emergence and spread of antibiotic resistance. Novel members as well as variants of existing members of this fa... Metallo-β-lactamases (MBLs) are a family of Zn2+-dependent enzymes that have contributed strongly to the emergence and spread of antibiotic resistance. Novel members as well as variants of existing members of this family are discovered continuously, compounding their threat to global health care. MBLs are divided into three subgroups, i.e. B1, B2 and B3. The recent discovery of an unusual MBL from Serratia proteamaculans (SPR-1) suggests the presence of an additional subgroup, i.e. B4. A database search reveals that SPR-1 has only one homologue from Cronobacter sakazakii, CSA-1.These two MBLs have a unique active site and may employ a mechanism distinct from other MBLs, but reminiscent of some organophosphate-degrading hydrolases. 展开更多
关键词 Antibiotic Resistance β-Lactam Antibiotics Metallo-β-lactamases Sequence Homology Serratia proteamaculans Cronobacter sakazakii
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Identification and preliminary characterization of novel B3-type metallo-β-lactamases
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作者 Manfredi Miraula Conor SBrunton +1 位作者 Gerhard Schenk Natasa Mitić 《American Journal of Molecular Biology》 2013年第4期198-203,共6页
Antibiotic resistance has emerged as a major global threat to human health. Among the strategies employed by pathogens to acquire resistance the use of metallo-β-lactamases (MBLs), a family of dinuclear metalloenzyme... Antibiotic resistance has emerged as a major global threat to human health. Among the strategies employed by pathogens to acquire resistance the use of metallo-β-lactamases (MBLs), a family of dinuclear metalloenzymes, is among the most potent. MBLs are subdivided into three groups (i.e. B1, B2 and B3) with most of the virulence factors belonging to the B1 group. The recent discovery of AIM-1, a B3-type MBL, however, has illustrated the potential health threat of this group of MBLs. Here, we employed a bioinformatics approach to identify and characterize novel B3-type MBLs from Novosphingobium pentaromativorans and Simiduia agarivorans. These enzymes may not yet pose a direct risk to human health, but their structures and function may provide important insight into the design and synthesis of a still elusive universal MBL inhibitor. 展开更多
关键词 Antibiotic Resistance β-Lactam Antibiotics Metallo-β-lactamases Sequence Homology Novosphingobium Pentaromativorans Simiduia Agarivorans
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Prevalence and Risk Factors of Penicillinase-Type β-Lactamase Producing Neisseria gonorrhoeae Isolated from Patients Attending Health-Facilities in Yaounde, Cameroon
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作者 Cécile Ingrid Djuikoue Laurene Nzangem Doumene +10 位作者 Cedric Seugnou Nana Joviale Magne Talla Herman Koyouo Tagne Blondelle Kitio Messeu Farid Wega Tobie Vianney Kamany Kamdem Willy Yamdeu Djonkouh Ghandhi Fossouo Ndieffouo Carole Tayimetha Benjamin D. Thumamo Pokam Nicolas Antoine-Moussiaux 《Open Journal of Medical Microbiology》 2023年第3期220-233,共14页
Background and Objectives: Mitigation of antibiotic resistant Neisseria gonorrhoeae has become a priority due to considerable health and economical disabilities it generates. In order to tackle the emergence of resist... Background and Objectives: Mitigation of antibiotic resistant Neisseria gonorrhoeae has become a priority due to considerable health and economical disabilities it generates. In order to tackle the emergence of resistant Neisseria gonorrhoeae, this study aimed to determine the prevalence and risk factors of penicillinase type β-lactamase-producing Neisseria gonorrheae among patients consulting for genital infectious disorders in two health-facilities in Yaounde, Cameroon. Materials and Method: A cross-sectional descriptive and analytical study was conducted over a 3-month period, from July 2<sup>nd</sup> to October 2<sup>nd</sup>, 2022. Vaginal and urethral secretions were collected. Biochemical identification tests were performed on colonies grown on chocolate agar + polyvitex using the Api NH gallery. The detection of penicillinases was equally performed using the API NH gallery and confirmed using the antimicrobial susceptibility testing. The Minimum Inhibitory Concentrations of some antibiotics were determined using the E-Test. Results: The results showed that out of the 198 patients sampled, 16 (8.08%) were positive for Neisseria gonorrhoeae, among which 13/16 (81.25%) were penicillinase-type β-lactamase producers. Antimicrobial susceptibility testing results showed high co-resistances to antibiotics, mainly ciprofloxacin (100%), nalidixic acid (92.31%) and azithromycin (84.62%). Moreover, high Minimum Inhibitory Concentrations of ceftriaxone (ranging from 6 to 24 mg/L) was observed toward Neisseria gonorrhoeae isolates. The risk factors of the carriage of penicillinase-type β-lactamase producing Neisseria gonorrhoeae identified were: a history of Sexually Transmitted infections (p = 0.01) and unprotected sexual intercourse (p = 0.01). Conclusion: The emergence of penicillinase-type β-lactamase producing Neisseria gonorrhoeae is increasing and the situation is becoming worrisome. The identified risk factors can constitute a basic outlook to tackle resistant Neisseria gonorrhoeae, and therefore sustain antibiotic stewardship. 展开更多
关键词 Neisseria gonorrhoeae Antimicrobial Resistance Β-lactamasE PENICILLINASE Cameroon
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L1 β-Lactamase催化反应机理研究 被引量:1
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作者 徐定国 鄢国森 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2008年第12期2453-2456,共4页
用混合量子力学和分子力学(QM/MM)方法和密度泛函理论讨论了L1β-Lactamase催化Nitrocefin水解的过程,研究结果表明,反应为多步反应:第一步亲核进攻反应为反应的决速步骤,并且伴随着酰胺键的断裂,第二步反应为质子迁移反应.同时讨论了... 用混合量子力学和分子力学(QM/MM)方法和密度泛函理论讨论了L1β-Lactamase催化Nitrocefin水解的过程,研究结果表明,反应为多步反应:第一步亲核进攻反应为反应的决速步骤,并且伴随着酰胺键的断裂,第二步反应为质子迁移反应.同时讨论了金属锌在反应中的作用. 展开更多
关键词 混合量子力学和分子力学(QM/MM) 密度泛函理论 Β-lactamasE 水解反应
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Prevalence and characteristics of extended spectrum β-lactamase-producing Escherichia coli from bovine mastitis cases in China 被引量:2
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作者 YANG Feng ZHANG Shi-dong +4 位作者 SHANG Xiao-fei WANG Xu-rong WANG Ling YAN Zuo-ting LI Hong-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1246-1251,共6页
The aim of the study was to investigate the prevalence and characterization of extended-spectrum β-lactamase (ESBL)- producing Escherichia coli isolated from bovine mastitis cases in China. ChromID ESBL agar was us... The aim of the study was to investigate the prevalence and characterization of extended-spectrum β-lactamase (ESBL)- producing Escherichia coli isolated from bovine mastitis cases in China. ChromID ESBL agar was used to confirm ESBL-producing E. coli. PCR and DNA sequencing were employed to characterize the genotype of ESBL-producers. Antimicrobial susceptibility was measured by disc diffusion. Overall, 73 of 318 E. coli isolates (22.96%) were identified as ESBL-producers. Of these ESBL-producing E. coli, the prevalence of blaCTX-M and blaTEM-1 was 97.26 and 71.23%, respectively. The predominant CTX-M-type ESBL was CTX-M-15 (65.75%), followed by CTX-M-14 (10.96%), CTX-M-55 (9.59%), CTX-M-64 (5.48%), CTX-M-65 (4.11%) and CTX-M-3 (1.37%). This study is the first report of CTX-M-64 and CTX-M-65 in E. coli isolated from bovine mastitis. Furthermore, 72 ESBL-producing E. coli isolates (98.63%) were found to be multidrug-resistance. This study noted high prevalence and rates of antimicrobial resistance of ESBL-producing E. coli isolates from bovine mastitis cases in China. 展开更多
关键词 extended spectrum β-lactamase Escherichia coli MULTIDRUG-RESISTANCE bovine mastitis
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Analysis of AmpC β-lactamase Gene in Pseudomonas aeruginosa 被引量:1
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作者 倪明 张东绅 齐俊英 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第1期17-19,23,共4页
The gene and the amino acid sequence of the structural and regulatory region of the Pseudomonas aeruginosa with different resistance patterns were analyzed. Six strains with different resistance patterns were selected... The gene and the amino acid sequence of the structural and regulatory region of the Pseudomonas aeruginosa with different resistance patterns were analyzed. Six strains with different resistance patterns were selected and the AmpC β-lactamase was identified. The objective gene fragment was amplified by colonies PCR. The sequences of the PCR-products were analyzed. The DNA sequence of the structural gene ampC and the regulatory genes ampR, ampD and ampE was detected. The 6 strains and the wild-type Pseudomonas aeruginosa are highly homogeneous in structural and regulatory region. Some new mutant points were found. 展开更多
关键词 Pseudomonas aeruginosa Β-lactamasE AmpC β-lactamase
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Antimicrobial Resistance and Genotype Analysis of Extended-Spectrum-β-Lactamase-Producing Proteus Mirabilis 被引量:1
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作者 Ying Huang Yuanhong Xu +1 位作者 Zhongxin Wang Xianghong Lin 《Open Journal of Clinical Diagnostics》 2014年第1期57-62,共6页
To analyse the genotypes of clinical isolates of Extended-Spectrum-β-Lactamase-Producing (ESBL-producing) Proteus mirabilis (P. mirabilis) and the mechanisms of antimicrobial resistance, to guide reasonable use of an... To analyse the genotypes of clinical isolates of Extended-Spectrum-β-Lactamase-Producing (ESBL-producing) Proteus mirabilis (P. mirabilis) and the mechanisms of antimicrobial resistance, to guide reasonable use of antibiotics and to avoid nosocomial outbreak infections by ESBL-producing P. mirabilis. 125 clinical isolates of P. mirabilis were collected from the Drug-Resistant Bacteria Surveillance Center of Anhui Province (from Jan 2009 to May 2010). Searching for the genotypes of ESBLs was perfomed by PCR amplification and DNA sequencing, and performed conjugation test simultaneously. Among ESBL-producing strains, CTX-M was the major genotype (3 CTX-M-13 and 1 CTX-M-3). TEM-1b spectrum β-lactamase was also prevalence in P. mirabilis. The diversity of β-lactamases in P. mirabilis and the emergency of multi-drug-resistance clinical strains will present serious threat to clinical therapy and even will lead to outbreak of nosocomial infections. Our study emphasizes the need for enhanced supervision of ESBL-producing P. mirabilis. Timely and reasonable drug-resistance data are indispensable to clinical therapy. 展开更多
关键词 GENOTYPE Extended-Spectrum-β-lactamase ANTIMICROBIAL Resistance PROTEUS Mirabilis
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Multidrug resistance extended spectrum β-lactamase and AmpC producing Escherichia coli isolated from the environment of Bogor Slaughterhouse,Indonesia
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作者 Mirnawati Bachrum Sudarwanto Denny Widaya Lukman +3 位作者 Trioso Purnawarman Hadri Latif Herwin Pisestyani Eddy Sukmawinata 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第8期708-711,共4页
Objective: To determine the multidrug resistance extended spectrum p-lactamase and AmpC(ESBL/AmpC producing) Escherichia coli(E. coli) isolated from the environment of Bogor slaughterhouse, Indonesia.Methods: A total ... Objective: To determine the multidrug resistance extended spectrum p-lactamase and AmpC(ESBL/AmpC producing) Escherichia coli(E. coli) isolated from the environment of Bogor slaughterhouse, Indonesia.Methods: A total of 35 samples from 7 locations in slaughterhouse i.e., source of water,slaughtering floor, swab of carcass area floor, swab of evisceration area floor, untreated waste water, treated waste water, drinking water for cattle were collected from March to April 2016. Presence of ESBL/AmpC producing E. coli and susceptibility testing against8 antimicrobial agents(penicillin G, streptomycin, gentamycin,ciprofloxacin, enrofloxacin, tetracycline, trimethoprim-sulfamethoxazole, and polymyxin B) were detected by disk diffusion test according to Clinical and Laboratory Standards Institute.Results: ESBL/AmpC producing E. coli were identified in 14.3%(5/35) of the collected samples from the environment of Bogor slaughterhouse. ESBL/AmpC-producing E. coli isolates were detected in untreated waste water(n=3), slaughtering floor(n=1), and carcass area floor(n=1). Most of ESBL/AmpC-producing E. coli isolates(80%) showed multidrug resistance phenotypes against at least three classes of antibiotics. The highest incidence of antibiotics resistance was against penicillin G(100.0%) and streptomycin(100.0%), followed by gentamicin(60.0%), trimethoprim-sulfamethoxazole(60.0%),tetracycline(40.0%), ciprofloxacin(40.0%), enrofloxacin(20.0%), and polymyxin B(0.0%).Conclusions: The transmission of antimicrobial resistant bacteria into the environment may be a potential risk for human health. 展开更多
关键词 Escherichia coli 环境 扩大光谱 -lactamase 屠场
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EXTRACELLULAR RELEASE OF β-LACTAMASE BY OSMOTIC SHOCK IN SYNECHOCOCCUS TRANSFORMANT
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作者 Shin-ichi Yano Yoshikazu Kawata Hiroyuki Kojima(Osaka National Research Institute, Agency of Industrial Science and Technology, Ikeda, Osaka 563, Japan ) 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1998年第S1期105-108,共4页
A unicellular cyanobacterium Synechococcus sp. strain PCC 7002 was transformedwith plasmid pQL1, on which β-lactamase gene (bla) and β-galactosidase gene (lacZ) were encoded.The transformant cells released β-lactam... A unicellular cyanobacterium Synechococcus sp. strain PCC 7002 was transformedwith plasmid pQL1, on which β-lactamase gene (bla) and β-galactosidase gene (lacZ) were encoded.The transformant cells released β-lactamase into medium by an abrupt drop of osmotic pressure. This re-sult indicates that this cyanobacterium recognizes and processes the signal sequence of β-lactamase, andaccumulates the enzyme in periplasm. Repeated release of β-lactamase was possible by repeated osmoticshocks without impairing cell viability. On the other hand, most of the β-galactosidase remained in cyto-plasm under the osmotic shock. 展开更多
关键词 SYNECHOCOCCUS perienzyme Β-lactamasE OSMOTIC shock
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Metallo-β-lactamase producing nonfermentative gram-negative bacteria:An increasing clinical threat among hospitalized patients
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作者 Varsha Gupta Shailpreet Sidhu Jagdish Chander 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第9期718-721,共4页
Objective:To detect and evaluate the various methods for metallo-β-lactamases(MBL) production in Pseudomonas aeruginosa(P.aeruginosa) and Acinetobacter species.Methods:A total of 109 P.aeruginosa and 85 Acinetobacter... Objective:To detect and evaluate the various methods for metallo-β-lactamases(MBL) production in Pseudomonas aeruginosa(P.aeruginosa) and Acinetobacter species.Methods:A total of 109 P.aeruginosa and 85 Acinetobacter species were screened for imipenem resistance by Kirby- Bauer disc diffusion methods.Detection of MBL production was(lone by imipenem-EDTA combined disc test,double disc synerygy test(DDST) and imipenem-EDTA MBL E test.Results: A total of 63(57.8%) strains of P.aeruginosa and 46(54.1%) strains of Acinetobacter spp.were found to be resistant to imipenem.Of the 63 imipenem resistant P.aeruginosa tested for MBL production.44(69.89;) were found to be positive and among 46 imipenem resistant Acinetobacter. 19(41.3%) were shown to be the MBL producers.Conclusions:Imipenem-EDTA combined disc test and MBL E test are equally effective for MBL detection in both P.aeruginosa and Acinetobacter spp.,but given the cost-constraints,combined disc can be used as a convenient screening method in the clinical microbiology laboratory. 展开更多
关键词 Carbapenem-imipenem Metallo-β-lactamases Non fermentative GRAM-NEGATIVE BACILLI
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Intestinal carriage of methicillin resistant Staphylococcus aureus and extended-spectrum β-Lactamase-producing Enterobacteriacae in hospitalized and nonhospitalized patients and their clinical implications
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作者 Hanan Ahmed Habib Babay Ali Mohammed Somily 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2009年第3期41-45,共5页
Objective:To determine the clinical implication of and intestinal carriage with methicillin resistant Staphylococcus aureus(MRSA) and extended spectrumβ-lactamase(ESBL)-producing Enterobacteriacae.Methods: A total of... Objective:To determine the clinical implication of and intestinal carriage with methicillin resistant Staphylococcus aureus(MRSA) and extended spectrumβ-lactamase(ESBL)-producing Enterobacteriacae.Methods: A total of 180 stool specimens were screened for MRSA and ESBL-producing enterobacteria.Identification of ESBL- producing Enterobacteriacae was done by MicroScan Walk Away 96 system(Dade Behring Inc.,West Sacramento,CA 95691,USA ) and confirmation by double-disc synergy test.MRSA was identified by disc diffusion using 30μg cefoxitin disc and the MicroScan.Results:The rate of fecal MRSA carriage was 7.8% (14/180),35.7%(5 /14) were recovered from surgical wards.Three patients(21,4%) had MRSA recovered from other body sites,and 2(14.2%) had in addition ESBL -producing Escherichia coli(E.coli) and Klebsiella pneumoniae(K.pneumoniae) respectively.Four(28.5%) patients with MRSA fical carriage died. MRSA fecal carriage was recovered from both inpatients and outpatients.Four(2.2%) cases carried ESBL-producing Enterobacteriacae in feces.Three(75%) were from intensive care unit(ICU).One patient had both ESBL-producing E.coli and K.pneumoniae from stool as well as E.coli from tracheal aspirate.Two ICU patients with fecal ESBL died.Conclusion:Fecal screening for MRSA and ESBL of all patients at high risk admitted to different hospital wards and ICUs and implementing infection control measures were recommended. 展开更多
关键词 INTESTINAL CARRIAGE METHICILLIN resistant Staphylococcus aureus EXTENDED spectrumβ-lactamase Enterobacteriacae
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Studies of β-lactamase production in ampicillin resistant Haemophilus influenzae
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作者 方正 陈海兵 +3 位作者 束学安 修清玉 罗文侗 戴旭明 《Journal of Medical Colleges of PLA(China)》 CAS 2000年第4期244-246,共3页
Objective:To study the molecular mechanisms of β-lactamase production in ampicillin resistant(AmP ) Hae- mophilus influenzae(HI). Methods: Identified the β-lactamases production strain from AmP HI was isolated from ... Objective:To study the molecular mechanisms of β-lactamase production in ampicillin resistant(AmP ) Hae- mophilus influenzae(HI). Methods: Identified the β-lactamases production strain from AmP HI was isolated from clinical cases with K-B method. β-lactamase encoding gene in enzyme production strains were detected by PCR with lactamase gene specific primers, and both plasmid and chromosomal DNA samples. Results: Thirty-two out of 36 (88 .9% ) were found to be β-lactamase production. Twenty-nine out of 32 enzyme production stain were PCR positive (the ratio of PCR positives 90.6% ). There were 25 stains amplified with plasmid DNA positively, and 4 with chromosomal DNA. Conclusion: (l ) Most of the AmPr HI strain produce lactamase is mediated by plasmid. (2) Detection of lactamase encoding gene in HI is a simple and efficient approach to study the molecular basis of ampicillin resistance. 展开更多
关键词 HAEMOPHILUS influenzae Β-lactamasE DRUG resistant MICROBIAL
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Prevalence and Potential Risk Factors of Hospital Acquired Extended-Spectrum Beta-Lactamase—Producing <i>Proteus</i>Species
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作者 Nagi A. Alhaj Muaath S. Alsafani Saleh S. Bahaj 《Open Journal of Medical Microbiology》 2019年第4期139-150,共12页
Background: Multidrug resistance and production of extended spectrum β-lactamases (ESBLs) by a large group of bacterial agents in hospitals are to be a matter of scientific concern. Objective: This cross-sectional st... Background: Multidrug resistance and production of extended spectrum β-lactamases (ESBLs) by a large group of bacterial agents in hospitals are to be a matter of scientific concern. Objective: This cross-sectional study was aimed to investigate the prevalence of ESBL producing Proteus species and risk factors associated with hospital acquired infection in addition to study the antibiotics susceptibility patterns of all bacterial isolates from inpatients of four Yemeni general hospitals. Methods: A total of 740 consecutive non-repeat culture isolates were obtained from admitted patients of Al-Kuwait University Hospital, Al-Thowra General Hospital, Al-Jumhori Teaching Hospital, and Military General Hospitals Sana’a city. We used Kirby-Bauer disk diffusion method to detect antimicrobial susceptibility and establish the presence of ESBLs-producing bacteria according to the Clinical and Laboratory Standards Institute guidelines. Results: Out of 740 isolate, 233 (31.5%) were Escherichia coli followed by Staphylococcus aureus 188 (25.4%), Pseudomonas aeruginosa 149 (20.1%), Klebsiella sp. 107 (14.5%), Enterococcus faecalis 25 (3.4%) and Proteus spp. 38 (5.1%). The highest frequencies of ESBLs producing among Proteus sp. were Proteus mirabilis 26 out 38 (68.4%) and Proteus vulgaris 12 out 38 (31.6%). The most effective of antimicrobial susceptibility pattern among Proteus spp. were Imipenem (100%) followed by Pipracillin-Tazobactam (92.3%) for P. mirabilis and (83.3%) for P. vulgaris, while the Amikacin (80.8%) for P. mirabilis and P. vulgaris with (91.7%). Amoxicillin and Cefotaxime were the highest for both species (100%). Conclusion: The prevalence of ESBL-producing Proteus spp. detected in this study is of great concern for public health authorities and a strict adherence of infection control policies and procedures with continuous antibiotics resistance surveillance including antimicrobial management and routine detection of ESBL-producing isolates are very important to prevent nosocomial infections. 展开更多
关键词 Extended Spectrum Β-lactamases HOSPITAL ACQUIRED Infection PROTEUS SPECIES Yemen
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Prevalence and Antimicrobial Susceptibility Profile of Metallo-<i>β</i>-Lactamase Producing <i>Pseudomonas aeruginosa</i>Isolates at Kenyatta National Hospital
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作者 Jane Njeri Karuitha Odera Susan Akinyi +1 位作者 Maina Anne Njeri Mureithi Marianne 《Advances in Microbiology》 2018年第11期885-893,共9页
Pseudomonas aeruginosa is a major cause of nosocomial infections with high mortality rates. The organism is highly resistant to most classes of drugs used and can develop resistance during treatment. One of the resist... Pseudomonas aeruginosa is a major cause of nosocomial infections with high mortality rates. The organism is highly resistant to most classes of drugs used and can develop resistance during treatment. One of the resistance mechanisms of P. aeruginosais is Metallo-β-Lactamase (MBL) production. MBL producing P. aeruginosa is a major health concern given it’s resistance to almost all available drugs. The prevalence of this resistant strain is unknown since there is no standardized method for testing MBL production. This was a laboratory based cross-sectional prospective study that was carried out from September 2015 to March 2016 at Kenyatta National Hospital. Ninety-nine isolates of P. aeruginosa were collected during the period and tested for antimicrobial susceptibility and isolates found to be resistant to imipenem tested for MBL production. The results indicated high resistance of P. aeruginosa to commonly used drugs. Of the isolates tested 69.7% were resistant to piperacillin, 63.6% were resistant to aztreonam, 58.6% were resistant to levofloxacin, 55.6% were resistant to cefipime, 65.7% were resistant to ceftazidime, 68.7% were resistant to ticarcillin-clavulanate, 72.2% were resistant to meropenem, 64.9% were resistance to imipenem while 86.4% of urine isolates were resistant to ofloxacin. Of the isolates resistant to imipenem 87.3% were found to be MBL producers. In conclusion, P. aeruginosais highly resistant to the drugs currently is used for treatment and resistance to carbapenems is largely due to MBL production. 展开更多
关键词 Pseudomonas aeruginosa METALLO-Β-lactamasE Antimicrobial Resistance Kenyatta NATIONAL HOSPITAL
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Phenotypic and Genotypic Characterization of Extended Spectrum β-Lactamase Klebsiella pneumoniae and Fluorescent Pseudomonas spp. Strains from Market Garden Products and Their Watering Water in Benin (West Africa)
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作者 Wassiyath Moussé Pacôme A. Noumavo +4 位作者 Nicodème W. Chabi Haziz Sina Majoie G. Tohoyessou Théodora A. Ahoyo Lamine Baba-Moussa 《Food and Nutrition Sciences》 2016年第3期192-204,共13页
Market garden products can carry several types of microorganisms, and their consumption is the source of many cases of food poisoning. This work aimed to improve food safety in Benin. In characterizing strains of K. p... Market garden products can carry several types of microorganisms, and their consumption is the source of many cases of food poisoning. This work aimed to improve food safety in Benin. In characterizing strains of K. pneumoniae and fluorescent Pseudomonas spp. at the biochemical and molecular level, the target was to identify contaminated watering water and garden products sold during Cotonou in both the dry and rainy seasons. A total of 164 samples of market garden products and 22 samples of watering water were investigated. The results showed that 5.91% of market garden products and watering water were contaminated by K. pneumoniae and 20.43% by fluorescent Pseudomonas spp. During the dry season, cabbage was most contaminated by fluorescent Pseudomonas spp. (50%). Pool water was more contaminated with K. pneumoniae (17%). All isolated strains were resistant to both amoxicillin and penicillin. All strains of K. pneumoniae and fluorescent Pseudomonas spp. were not resistant to imipenem, and 22% of them produced penicillinase. Among the 49 strains producing penicillinase isolated, 64.29% and 21.43% carried bla<sub>TEM</sub> and bla<sub>SHV</sub> respectively while 14.28% carried bla<sub>CTX-M</sub> genes. In light of the previously-developed results and considering the importance of horticultural products in Beninese food habits, we must improve national awareness of the risk for foodborne illness. 展开更多
关键词 Vegetables Klebsiella pneumoniae Fluorescent Pseudomonas spp. Β-lactamases Food Safety
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