perazinyl)-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid] (Fig. 1) is a broad spectrum fluoroquinolone antibacterial, which is effective against a wide range of Gram-positive and Gram-negative bacteria (1). Fluoroquinolones are sensitive to light (2) and studies have been carried out on the photodegradation of quinolones (3), fluoroquinolones (4), ciprofloxacin (5, 6), sparfloxaci...

The quinolones trap DNA gyrase and DNA topoisomerase IV on DNA as complexes in which the DNA is broken but constrained by protein. Early studies suggested that drug binding occurs largely along helix-4 of the GyrA (gyrase) and ParC (topoisomerase IV) proteins. However, recent X-ray crystallography shows drug intercalating between the -1 and +1 nucleotides of cut DNA, with only one end of the dr...

enoxacin and norfloxacin on inclusion development and infectivity. The MICs and MLCs of these drugs are compared in Table 1. There was considerable variation in the sensitivity of C. trachomatis to these quinolones, which may reflect their varying ability to penetrate eukaryotic cells. However, at effective concentrations, the action of each drug was lethal, i.e. infectivity was not affected by...

The increased use of fluoroquinolones has led to increasing resistance to these antimicrobials, with rates of resistance that vary by both organism and geographic region. Resistance to fluoroquinolones typically arises as a result of alterations in the target enzymes (DNA gyrase and topoisomerase IV) and of changes in drug entry and efflux. Mutations are selected first in the more susceptible t...

Trovafloxacin was found to be a typical quinolone producing a biphasic dose response against Escherichia coli, Staphylococcus aureus or Streptococcus pneumoniae. A reduced rate of kill was seen against Enterococcus faecalis, which is also typical of the quinolones. However, the bactericidal activity of trovafloxacin against S. aureus and S. pneumoniae was greater than most other quinolones prev...

ABSTRACT Background and Objectives: One major source of antibiotic contamination in the sea is from aquaculture. We monitored concentration commonly used classes resistance genes ( tet (M), sul1, sul2 sul3 ) aquaculture farms Peninsular Malaysia. Methods: Antibiotic residues were quantified using high-performance liquid chromatography real-time PCR respectively. Risk quotients European technica...

Quinolones are potent antibacterial agents that specifically target bacterial DNA gyrase and topoisomerase IV. Widespread use of these agents has contributed to the rise of bacterial quinolone resistance. Previous studies have shown that quinolone resistance arises by mutations in chromosomal genes. Recently, a multiresistance plasmid was discovered that encodes transferable resistance to quino...

INTRODUCTION Diabetes mellitus and the postmenopausal period are associated with increased risk of urinary tract infections (UTIs) in women. However, data on UTIs in postmenopausal diabetic women are scarce. OBJECTIVES The aim of this study was to determine the prevalence of UTIs in postmenopausal women with type 2 diabetes mellitus, identify the potential risk factors, describe the causative p...