fluoroquinolones
Mechanisms of Action: Physiological EffectsA Roadblock-and-Kill Mechanism of Action Model for the DNA-Targeting Antibiotic CiprofloxacinFluoroquinolones, antibiotics that cause DNA damage by inhibiting DNA topoisomerases, are clinically important, but their mechanism of action is not yet fully understood. In particular, the dynamical response of bacterial cells to fluoroquinolone exposure has hardly been investigated, although the SOS response, triggered by DNA damage, is often thought to play a key role. Here, we investigated the growth inhibition of the bacterium...
Mechanisms of ResistancePathogenicity Genomic Island-Associated CrpP-Like Fluoroquinolone-Modifying Enzymes among Pseudomonas aeruginosa Clinical Isolates in EuropeMany transferable quinolone resistance mechanisms have been identified in Gram-negative bacteria. The plasmid-encoded 65-amino-acid-long ciprofloxacin-modifying enzyme CrpP was recently identified in Pseudomonas aeruginosa isolates. We analyzed a collection of 100 clonally unrelated and multidrug-resistant...
Experimental TherapeuticsNitroxide Functionalized Antibiotics Are Promising Eradication Agents against Staphylococcus aureus BiofilmsTreatment of biofilm-related Staphylococcus aureus infections represents an important medical challenge worldwide, as biofilms, even those involving drug-susceptible S. aureus strains, are highly refractory to conventional antibiotic therapy. Nitroxides were recently shown to induce the dispersal of...
Mechanisms of Action: Physiological EffectsDAV131A Protects Hamsters from Lethal Clostridioides difficile Infection Induced by FluoroquinolonesFluoroquinolone treatments induce dysbiosis of the intestinal microbiota, resulting in loss of resistance to colonization by exogenous bacteria such as Clostridioides difficile that may cause severe diarrhea in humans and lethal infection in hamsters. We show here that DAV131A, a charcoal-based adsorbent, decreases the intestinal levels of the fluoroquinolone...
Mechanisms of ResistanceReactive Oxygen Species Production Is a Major Factor Directing the Postantibiotic Effect of Fluoroquinolones in Streptococcus pneumoniaeWe studied the molecular mechanisms involved in the postantibiotic effect of the fluoroquinolones levofloxacin and moxifloxacin in Streptococcus pneumoniae. Wild-type strain R6 had postantibiotic effects of 2.05 ± 0.10 h (mean ± standard deviation [SD]) and 3.23 ± 0.45 h at 2.5× and 10× MIC of levofloxacin, respectively. Moxifloxacin exhibited lower effects of 0.87 ±...
Clinical TherapeuticsFluoroquinolones in Drug-Resistant Tuberculosis: Culture Conversion and Pharmacokinetic/Pharmacodynamic Target Attainment To Guide Dose SelectionFluoroquinolones are group A drugs in tuberculosis guidelines. We aim to compare the culture conversion between new-generation (levofloxacin and moxifloxacin) and old-generation (ciprofloxacin and ofloxacin) fluoroquinolones, develop pharmacokinetic models, and calculate target attainment for levofloxacin and moxifloxacin. We included three U.S. tuberculosis centers.
Clinical TherapeuticsPharmacokinetics of Levofloxacin in Children Treated for Exposure to Drug-Resistant TuberculosisLevofloxacin is used to treat and prevent drug-resistant tuberculosis in children. We assessed levofloxacin serum drug concentrations in 24 children aged 2 to 10 years who received levofloxacin-based tuberculosis preventive therapy in Karachi, Pakistan.
Mechanisms of ResistanceResistance and Virulence Mechanisms of Escherichia coli Selected by Enrofloxacin in ChickenThis study aimed to investigate the genetic characteristics, antibiotic resistance patterns, and novel mechanisms involved in fluoroquinolone (FQ) resistance in commensal Escherichia coli isolates. The E. coli isolates were recovered from a previous clinical study and subjected to antimicrobial...
