The antimicrobial activities of two investigational fluoroquinolones (CI-960 and E4695) were compared with those of five similar compounds and four comparison drugs against 103 strains of Legionella pneumophila and five other Legionella species type strains. When concentrations inhibiting 90% of strains tested (MIC90s) for L. pneumophila were determined, CI-960 and temafloxacin emerged as the m...

Antibiotics resistance poses catastrophic threat to global public health. Novel insights into the underlying mechanisms of action will inspire better measures to control drug resistance. Fluoroquinolones are potent and widely prescribed broad-spectrum antibiotics. Bacterial protein degradation pathways represent novel druggable target for the development of new classes of antibiotics. Mycobacte...

We calculated the magnitude of various serum pharmacodynamic parameters for fluoroquinolones in models of experimental endocarditis (EE) described in the literature. Nineteen publications contained data that allowed calculation of these parameters. Data were available for eight fluoroquinolones against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, methicillin-r...

Simian virus 40 large T-antigen (SV40 LT-Ag) is a 708 amino acid nuclear phosphoprotein. Among many functions of LT-Ag is its ability to perform as an ATPase-helicase, catalyzing the unwinding of viral genome during replication. The LT-Ag has been employed in the studies of helicase structure and function, and has served as a model helicase for the screening of antiviral drugs that target viral...

AIM To study the relationship between quantitative structure and pharmacokinetics (QSPkR) of fluoroquinolone antibacterials. METHODS The pharmacokinetic (PK) parameters of oral fluoroquinolones were collected from the literature. These pharmacokinetic data were averaged, 19 compounds were used as the training set, and 3 served as the test set. Genetic function approximation (GFA) module of Ce...

Newer fluoroquinolones such as ciprofloxacin, pefloxacin, ofloxacin, enoxacin, and fleroxacin are potent antimicrobial agents against many gram-negative bacteria, including Pseudomonas aeruginosa species and staphylococci-sensitive or resistant to methicillin. They are almost completely absorbed when given orally, reaching therapeutic plasma and dialysate concentrations, and their long half liv...

The selection of antibiotic-resistant mutant bacteria is proposed to occur in a drug concentration range (the mutant selection window) that extends from the minimum inhibitory concentration (MIC) of susceptible cells to the MIC of the least susceptible, single-step bacterial mutants (the mutant prevention concentration [MPC]). MPCs were estimated for tobramycin, chloramphenicol, rifampicin, pen...

The in vitro activity of trovafloxacin against 125 strains of Mycoplasma species and Ureaplasma urealyticum, including fluoroquinolone-susceptible and fluoroquinolone-resistant species, was compared to those of other fluoroquinolones, doxycycline, and erythromycin. The MIC at which 90% of isolates are inhibited for all fluoroquinolone-susceptible strains was 0.25 microg/ml. Whatever the associa...

The antibacterial spectrum of besifloxacin, a novel fluoroquinolone recently approved for treatment of ocular infections, was studied using 2,690 clinical isolates representing 40 species. Overall, besifloxacin was the most potent agent tested against gram-positive pathogens and anaerobes and was generally equivalent to comparator fluoroquinolones in activity against most gram-negative pathogen...

We determined the microbicidal activities of antibacterials against nonreplicating Mycobacterium smegmatis grown in a starvation-based Loebel model for persistence. Whereas most drugs lost their activity, fluoroquinolones retained lethal potency. Dose-response characterizations showed a paradoxical more-drug-kills-less Eagle effect. Pretreatment of cultures with chloramphenicol blocked the leth...