Selection of Streptococcus pneumoniae mutants having reduced susceptibility to moxifloxacin and levofloxacin.
نویسندگان
چکیده
With Streptococcus pneumoniae, moxifloxacin was 4- and 10-fold more effective than levofloxacin at restricting selection of resistant mutants and at killing resistant mutants, respectively. The selection frequency for first-step topoisomerase mutants was 1,000 times lower for moxifloxacin than for levofloxacin; this difference was lost when second-step mutants were selected.
منابع مشابه
Pharmacodynamic assessment based on mutant prevention concentrations of fluoroquinolones to prevent the emergence of resistant mutants of Streptococcus pneumoniae.
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متن کاملPharmacodynamics of moxifloxacin, levofloxacin and sparfloxacin against Streptococcus pneumoniae.
An in vitro pharmacokinetic model (IVPM) was used to simulate the human serum pharmacokinetics of moxifloxacin, levofloxacin and sparfloxacin, and to compare their pharmacodynamics against Streptococcus pneumoniae exhibiting a wide range of susceptibilities to fluoroquinolones. Logarithmic-phase cultures were exposed to peak concentrations achieved in human serum of moxifloxacin, levofloxacin o...
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متن کاملSelection of quinolone resistance in Streptococcus pneumoniae exposed in vitro to subinhibitory drug concentrations.
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عنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 46 2 شماره
صفحات -
تاریخ انتشار 2002