objective(s) methicillin-resistant staphylococcus aureus (mrsa) is an important cause of nosocomial and community infections. biofilm formation, mediated by a polysaccharide intercellular adhesin (pia) and encoded by the ica operon, is considered to be an important virulence factor in both s. epidermidis and s. aureus. however, the clinical impact of the ica locus and pia production is less wel...

OBJECTIVES We investigated the antimicrobial susceptibilities and resistance mechanisms of cattle-adapted Salmonella enterica serovar Dublin isolated in Japan in the past 30 years. This study is an example of evaluation of the impact of introduction of antimicrobials in veterinary medical practice on the selection of resistance in S. enterica. METHODS The antimicrobial susceptibilities and pr...

Background & Aims: Type 1 fimbriae is the most common adhesion factor in urine tract infection. In this Study, presence of virulence genes in isolated strains of uropathogenic E.Coli, O serotyping and molecular detection of phase variation of type 1 fimbriae were assessed during solid surfaces exposure. Methods: Isolated E.coli from urine samples of patients were serotyped by using serologic me...

Seven Klebsiella pneumoniae and four Klebsiella oxytoca clinical isolates with different levels of resistance to ciprofloxacin were studied. Mutations in the topoisomerase genes were found in almost all strains, but the contribution of a multidrug efflux system homologous to AcrAB in Escherichia coli was also observed. Overexpression of this efflux system was demonstrated by immunoblotting with...

Transposon mutagenesis of a clinical isolate of Morganella morganii, G1492 (tigecycline MIC of 4 microg/ml), yielded two insertion knockout mutants for which tigecycline MICs were 0.03 microg/ml. Transposon insertions mapped to acrA, which is constitutively overexpressed in G1492, suggesting a role of the AcrAB efflux pump in decreased susceptibility to tigecycline in M. morganii.

OBJECTIVE To investigate the contribution of gyrA mutation and efflux pumps to fluoroquinolone resistance and multidrug resistance among Escherichia coli isolates from dogs and cats. SAMPLE POPULATION 536 clinical isolates of E coli. PROCEDURES Minimum inhibitory concentrations (MICs) were determined for enrofloxacin and 6 other drug classes by use of broth microdilution techniques. Real-ti...