Selection of quinolone resistance in Streptococcus pneumoniae exposed in vitro to subinhibitory drug concentrations
نویسندگان
چکیده
منابع مشابه
Selection of quinolone resistance in Streptococcus pneumoniae exposed in vitro to subinhibitory drug concentrations.
OBJECTIVES Does exposure to subinhibitory concentrations of quinolones favour overexpression of efflux pumps or selection of target site mutations? METHODS ATCC 49,619 (fully susceptible) and SP32 (clinical isolate with PmrA-mediated efflux and mutation in ParE) were exposed for 24 h in broth to ciprofloxacin, levofloxacin, moxifloxacin or garenoxacin at concentrations of 0.5x the MIC, with d...
متن کاملSubinhibitory concentrations of penicillin increase the mutation rate to optochin resistance in Streptococcus pneumoniae.
OBJECTIVES The aim of this work was to study the effect of subinhibitory concentrations of penicillin, chloramphenicol and erythromycin on the mutation rate of Streptococcus pneumoniae. METHODS The mutation rate to rifampicin and optochin resistance was estimated using fluctuation analysis in three capsulated S. pneumoniae strains, cultured both with and without different subinhibitory antibi...
متن کاملResistance among Streptococcus pneumoniae: Implications for drug selection.
Streptococcus pneumoniae is an important pathogen in many community-acquired respiratory infections in the United States and a leading cause of morbidity and mortality worldwide. Unfortunately, S. pneumoniae is becoming increasingly resistant to a variety of antibiotics. Results of recent surveillance studies in the United States show that the prevalence of penicillin-nonsusceptible S. pneumoni...
متن کاملThe molecular epidemiology of Streptococcus pneumoniae with quinolone resistance mutations.
BACKGROUND The purpose of this study was to determine the prevalence of fluoroquinolone resistance and quinolone resistance-determining region (QRDR) mutations among Streptococcus pneumoniae isolates in the United States during the period of 2001-2002. A second objective was to examine the genetic relatedness of pneumococcal isolates with parC and/or gyrA mutations during the period of 1994-200...
متن کاملIn vitro selection of resistance to clinafloxacin, ciprofloxacin, and trovafloxacin in Streptococcus pneumoniae.
Ability of daily sequential subcultures in subinhibitory concentrations of clinafloxacin, ciprofloxacin, and trovafloxacin to select resistant mutants was studied in 10 pneumococci (ciprofloxacin MICs, 1 to 4 microg/ml, and clinafloxacin and trovafloxacin MICs, 0.06 to 0.125 microg/ml [n = 9]; ciprofloxacin, clinafloxacin, and trovafloxacin MICs, 32, 0.5, and 2 microg/ml, respectively [n = 1])....
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ژورنال
عنوان ژورنال: Journal of Antimicrobial Chemotherapy
سال: 2007
ISSN: 0305-7453,1460-2091
DOI: 10.1093/jac/dkm292