Abstract Background Quinolones and cephalosporins are antibiotic agents with activity against Gram-positive Gram-negative bacteria. They contain chromophores amine groups which electron-rich centres capable of donating electrons to electron-deficient compounds. A survey the literature revealed that 2, 4-dinitro-1-naphthol, a nitroaromatic useful in chemical synthesis, can accept charge transfer...

The quinolones differ in their mechanisms of bacterial killing. The rate of bacterial killing by quinolones can be influenced by the addition of bacterial protein or RNA synthesis inhibitors, and the growth phase of the bacterium. In this study, we compared the killing activities of gatifloxacin, trovafloxacin, ciprofloxacin and norfloxacin against staphylococci, pneumococci and Escherichia col...

The bactericidal activity of levofloxacin was compared with that of four other quinolones and one cephalosporin against four strains of Streptococcus pneumoniae with varying degrees of penicillin G susceptibility. Levofloxacin was found to be the most bactericidal quinolone at its optimum bactericidal concentration, followed by ofloxacin, ciprofloxacin, sparfloxacin and D-ofloxacin, in that ord...

PURPOSE Reports evaluating diagnosis and cross reactivity of quinolone hypersensitivity have revealed contradictory results. Furthermore, there are no reports investigating the cross-reactivity between gemifloxacin (GFX) and the others. We aimed to detect the usefulness of diagnostic tests of hypersensitivity reactions to quinolones and to evaluate the cross reactivity between different quinolo...

The importance of oxidase-positive, nonfermentative, Gram-negative bacilli in a variety of pathological processes is becoming increasingly important. Oligella urethralis is an organism which is normally isolated as a commensal from the genitourinary tract. We have described one case of urinary tract infection caused by this organism. This isolated organism is found to be resistant to quinolones...

Mycobacterium leprae, the causative agent of leprosy, is noncultivable in vitro; therefore, evaluation of antibiotic activity against M. leprae relies mainly upon the mouse footpad system, which requires at least 12 months before the results become available. We have developed an in vitro assay for studying the activities of quinolones against the DNA gyrase of M. leprae. We overexpressed in Es...

Recently, a number of novel quinolones with potent activity against topoisomerase II and eukaryotic cells have been described. Many of these compounds contain aromatic substituents in their C-7 ring positions. To determine whether pyrimido[1,6-a]benzimidazoles, a class of drugs modeled on quinolones, also display activity toward eukaryotic systems, the effects of Ro 46-7864 and Ro 47-3359 on Dr...

Introduction Campylobacter, especially C. jejuni, is one of the most common bacterial causes of diarrhoeal illness in humans (1). Feierl et al. (2) reported 3,771 cases of illness caused by C. jejuni in Austria in 2003, corresponding to an incidence of 46.5 per 100,000 inhabitants. The resistance of Campylobacter to quinolones is increasingly limiting their therapeutic use. The rise in human in...

The bactericidal activity of two new 4-quinolones, DU-6859a and DV-7751a, was investigated against strains of Escherichia coli, Staphylococcus aureus, S. epidermidis, Streptococcus pneumoniae and Enterococcus faecalis. DU-6859a and DV-7751a were more bactericidal than any 4-quinolone tested previously. Furthermore, DU-6859a was unique among 4-quinolones in being able to kill Ent. faecalis after...