background: acinetobacter baumannii, is an opportunistic pathogen and is responsible for numerous nosocomial infections. in recent years, this microorganism has been resistant to a wide range of antibiotics. one of the most important mechanisms of resistance in this microorganism is production of metallo-beta-lactamases (mbls). objectives: the aim of this study was to detect vim- and imp-type m...

background: ctx-m-type β-lactamases are increasingly becoming the predominant esbls globally in recent years. integrons are genetic elements which can integrate gene cassettes, usually antibiotic resistance genes. objectives: the aims were to determine antibiotic susceptibility and to detect genes encoding ctx-m-1 group enzymes and class 1, 2, and 3 integrons among the klebsiella pneumoniae iso...

conclusions the results of this study show that the rate of p. aeruginosa-caused burn wound infections was very high, and many of the isolates were resistant to three or more classes of antimicrobials. such extensive resistance to antimicrobial classes is important because few treatment options remain for patients with burn wound infections. blaimp-producing p. aeruginosa isolates are a rising ...

background pseudomonas aeruginosa is a leading cause of infections especially in patients with weakened immune systems. this pathogen is intrinsically resistant to many antibacterial agents. objectives the aim of this study was to survey the antibiotic resistance pattern and frequency of bla oxa10 gene in carbapenemase producing p. aeruginosa isolated from patients in isfahan hospitals. materia...

conclusion although all esbl producer gram-negative bacteria were sensitive to imipenem, piperacillin-tazobactam, and colistin, non-esbl isolates showed resistant pattern. interestingly, notable percent of mentioned resistant isolates were sensitive to nitrofurantoin. background resistance in enteric gram-negative bacteria is of a great concern and concise local data are lacking. objectives to ...

OBJECTIVES The hypothesis that BRO-1 selectively replaced the BRO-2 isoform of the Moraxella catarrhalis BRO beta-lactamase was tested by examining the temporal distribution, antibiotic resistance and epidemiological characteristics of isolates from a long-term collection at a single locale. METHODS A rapid, one-step PCR assay conducted on 354 isolates spanning 1984-1994 distinguished bro all...

Two clinical isolates of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae were noted to be less susceptible than expected to imipenem. Both were missing outer membrane proteins that serve as channels for antibiotic entry. The role of beta-lactamase in resistance was investigated by eliminating the original ESBL and introducing plasmids encoding various ESBLs and AmpC beta...

Production of staphylococcal beta-lactamase was shown to be correlated with penicillin G minimum inhibitory concentrations (MICs) of greater than 0.05 microgram/ml for 97% of the Staphylococcus aureus and 99% of the Staphylococcus epidermidis strains tested. However, it is important to note that of the isolates for which MICs were equal to or less than 0.05 micro/ml, a significant percentage (1...

The Met69-->Ile mutant of the OHIO-1 beta-lactamase, an SHV-family enzyme, is resistant to inactivation by beta-lactamase inhibitors. Analysis of purified Met69-->Ile enzyme reveals that its isoelectric point (pI 7.0) and CD spectrum are identical with those of the OHIO-1 enzyme. Levels of beta-lactamase expression in Escherichia coli as determined by immunoblotting are similar for OHIO-1 and M...

In Pseudomonas aeruginosa, resistance to cefclidin is usually associated with resistance to another third-generation cephalosporin, ceftazidime. In this study we analysed 22 isolates of P. aeruginosa, collected at Showa University Fujigaoka Hospital between 1992 and 1993, which were resistant to cefclidin but susceptible to ceftazidime. All polymerase chain reaction (PCR) products amplified by ...