[Time-killing curves of Pseudomonas aeruginosa strains exposed to polymyxin B].
The time-killing curves of three strains of Pseudomonas aeruginosa (PA01, ATCC10145 and ATCC27853) exposed to five concentrations of polymyxin B comprised: a latency phases, one or two decreasing phases and for the low polymyxin B concentrations a growth phasis. The five antibiotic concentrations were chosen to have a weak bactericidal effect such that decreasing exponential or biexponential models can be fitted to the data. In our experimental conditions, increasing Ca++ and Mg++ concentrations in the medium (Mueller-Hinton) reduced the bactericidal effect and increased the growth phases. Increasing inoculum (10(5) to 10(7) CFU/ml) decreased the bactericidal effect observed with polymyxin B.
Peyret
M
M
Laboratoire de Bactériologie, Centre Hospitalier Lyon-Sud, Pierre-Bénite.
Flandrois
J P
JP
Fardel
G
G
D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D011112:Polymyxin B / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013997:Time Factors
D011112:Polymyxin B
Etude de la courbe de mortalité de souches de Pseudomonas aeruginosa exposées à la polymyxine B.