Document Detail


Semimechanistic pharmacokinetic-pharmacodynamic model with adaptation development for time-kill experiments of ciprofloxacin against Pseudomonas aeruginosa.
MedLine Citation:
PMID:  20368392     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The objective of this study was to implement a semimechanistic pharmacokinetic-pharmacodynamic (PK-PD) model to describe the effects of ciprofloxacin against Pseudomonas aeruginosa in vitro. Time-kill curves were generated with an initial inoculum close to 5 x 10(6)CFU/ml of P. aeruginosa PAO1 and constant ciprofloxacin concentrations between 0.12 and 4.0 microg/ml (corresponding to 0.5x and 16x MIC). To support the model, phenotypic experiments were conducted with the PAO7H mutant strain, which overexpresses the MexEF OprN efflux pump and phenyl arginine beta-naphthylamide (PAbetaN), a known efflux inhibitor of main Mex multidrug efflux systems. A population approach was used for parameter estimation. At subinhibitory ciprofloxacin concentrations (0.12 and 0.25 microg/ml), an initial CFU decay followed by regrowth was observed, attesting to rapid emergence of bacteria with increased but moderate resistance (8-fold increase of MIC). This phenomenon was mainly due to an overexpression of the Mex protein efflux pumps, as shown by a 16-fold diminution of the MIC in the presence of PAbetaN in these strains with low-level resistance. A PK-PD model with adaptation development was successfully used to describe these data. However, additional experiments are required to validate the robustness of this model after longer exposure periods and multiple dosing regimens, as well as in vivo.
Authors:
Nicolas Grégoire; Sophie Raherison; Claire Grignon; Emmanuelle Comets; Manuella Marliat; Marie-Cécile Ploy; William Couet
Publication Detail:
Type:  In Vitro; Journal Article     Date:  2010-04-05
Journal Detail:
Title:  Antimicrobial agents and chemotherapy     Volume:  54     ISSN:  1098-6596     ISO Abbreviation:  Antimicrob. Agents Chemother.     Publication Date:  2010 Jun 
Date Detail:
Created Date:  2010-05-18     Completed Date:  2010-09-14     Revised Date:  2011-03-03    
Medline Journal Info:
Nlm Unique ID:  0315061     Medline TA:  Antimicrob Agents Chemother     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2379-84     Citation Subset:  IM    
Affiliation:
Université de Poitiers, CHU Poitiers, INSERM Eri-23, Poitiers, France2 France.
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MeSH Terms
Descriptor/Qualifier:
Anti-Bacterial Agents / administration & dosage,  pharmacokinetics*,  pharmacology*
Bacterial Outer Membrane Proteins / genetics,  metabolism
Ciprofloxacin / administration & dosage,  pharmacokinetics*,  pharmacology*
Colony Count, Microbial
Cross Infection / drug therapy,  microbiology
Dipeptides / metabolism
Drug Resistance, Bacterial / genetics
Genes, Bacterial
Humans
Microbial Sensitivity Tests
Models, Biological
Mutation
Pseudomonas Infections / drug therapy,  microbiology
Pseudomonas aeruginosa / drug effects*,  genetics,  metabolism
Chemical
Reg. No./Substance:
0/Anti-Bacterial Agents; 0/Bacterial Outer Membrane Proteins; 0/Dipeptides; 0/OprN protein, Pseudomonas aeruginosa; 0/phenylalanine arginine beta-naphthylamide; 85721-33-1/Ciprofloxacin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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