The veterinary cephalosporin drug ceftiofur is rapidly degraded in the bovine intestinal tract. A cylinder-plate assay was used to detect microbiologically active ceftiofur, and high-performance liquid chromatography-mass spectrometry analysis was used to quantify the amount of ceftiofur remaining after incubation with bovine intestinal anaerobic bacteria, which were isolated from colon content...

Objective: In addition to assessing the phenotypic development of biofilms and beta-lactamases, in current study, Pseudomonas aeruginosa isolates from intensive care units (ICU) patients with prevalent drug resistance are being evaluated. Methods: Standard CLSI recommended protocols were utilized detect beta-lactamases such as extended-spectrum β-lactamases (ESBL), metallo beta-lactamase (MBL),...

M et al. Rapid detection of the O25b-ST131 clone of Escherichia coli encompassing the CTX-M-15-producing strains. 2 Clermont O, Lavollay M, Vimont S et al. The CTX-M-15-producing Escherichia coli diffusing clone belongs to a highly virulent B2 phylogenetic subgroup. 3 Karisik E, Ellington MJ, Livermore DM et al. Virulence factors in Escherichia coli with CTX-M-15 and other extended-spectrum b-l...

Plasmid-encoded resistance to broad-spectrum cephalosporins and aztreonam is becoming a widespread phenomenon in clinical medicine. These antibiotics are inactivated by an array of different extended-spectrum beta-lactamases (ESBLs) which have evolved by point mutations of parental TEM or SHV beta-lactamases. In a previous study conducted during 1994-1995, SHV-2, SHV-2a and SHV-5 beta-lactamase...

An extended-spectrum B-lactamase (ESBL)-producing Providencia stuartii isolate was studied. A qnrA1 gene co-expressing blaVEB-1 gene was detected. Both genes were transferred to the recipient strain. The ciprofloxacin MIC of recipient strain increased tenfold. The blaVEB-1 gene persisted in microorganisms in Turkey but it also spread with PMQR genes to other species. The combination of PMQR wit...

1. Mammeri H, Eb F, Berkani A et al. Molecular characterization of AmpC-producing Escherichia coli clinical isolates recovered in a French hospital. J Antimicrob Chemother 2008; 61: 498–503. 2. Nordmann P, Mammeri H. Extended-spectrum cephalosporinases: structure, detection, and epidemiology. Future Microbiol 2007; 2: 297–307. 3. Mammeri H, Poirel L, Nordmann P. Extension of the hydrolysis spec...

Introduction: Salmonella sp infections have been reported over recent years in hospitals in Argentina and other countries due to multiresistant strains. The aim of this study was to characterize the extended-spectrum β-lactamases in third-generation cephalosporin-resistant strains of Salmonella enterica serovar Oranienburg. Methods: We studied 60 strains isolated from children with gastroenteri...

In the past 3 decades, classical extended-spectrum beta-lactamases (ESBLs) have probably been the main contributors to gram-negative antimicrobial resistance in Singapore. These appear to be being replaced by the newer CTX-M ESBLs. Metallo-beta-lactamases are found in Pseudomonas aeruginosa but do not seem to have spread widely in Acinetobacter spp. and Enterobacteriaceae. Carbapenem-hydrolysin...