Quinolones are currently used as empirical therapy for treatment of community-acquired lower respiratory infections as they are effective against a broad range of conventional bacterial and 'atypical' pathogens, including Chlamydia pneumoniae. C. pneumoniae is estimated to be associated with 10-20% of community-acquired pneumonia in adults, and has recently been suggested to play a role in seve...

This review focuses on the most recent research findings on adverse reactions caused by quinolone antibiotics. Reactions of the gastrointestinal tract, the central nervous system (CNS) and the skin are the most often observed adverse effects. Occasionally major events such as phototoxicity, cardiotoxicity, arthropathy and tendinitis occur, leading to significant tolerability problems. Over the ...

Mycobacterium tuberculosis (MTB) is capable of invading not only macrophages (Mphis) but also type II pneumocytes. In this study, we compared the antimicrobial activities of fluoroquinolones, including gatifloxacin, sitafloxacin and levofloxacin, against the MTB replication in the Mono Mac 6 human Mphi cell line (MM6-Mphis) and the A-549 human type II alveolar epithelial cell line (A-549 cells)...

PURPOSE To assess the in vitro susceptibility of Streptococcus pneumoniae, Staphylococcus aureus and coagulase-negative staphylococci (CoNS) ocular isolates to antibiotics, and identify changing trends in resistance over a 10-year period. METHODS All isolates from ocular infections collected between 2000 and 2009 were prospectively tested against several antibiotics in vitro. S. pneumoniae is...

This study investigated the presence and distribution of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides, in the water, sediments, and biota samples from Baiyangdian Lake, China. A total of 132 samples were collected in 2008 and 2010, and laboratory analyses revealed that antibiotics were widely distributed in the lake. Sulfonamides were the dominant antibiotic...

Quinolones (nalidixic acid--NAL, norfloxacin--NOR, ciprofloxacin--CIP and gatifloxacin--GAT) were tested against Escherichia coli isolated from urine (385 patient samples) by disk diffusion (DD) and agar dilution (AD) methods. Fifty-three samples (13.8%) were classified as resistant to at least one of the quinolones tested. CIP and NOR susceptibilities were the same (91.4%) and they were simila...

Sixty recent Streptococcus pneumoniae isolates with different susceptibilities to ciprofloxacin (14 with MIC 0.5 mg/L, 10 with MIC 1 mg/L, eight with MIC 2 mg/L, 11 with MIC 4 mg/L and 17 with MIC > or =8 mg/L) were tested against five new quinolones using Todd-Hewitt broth with and without 80% serum. The final inoculum was 5 x 10(5) cfu/mL. Gemifloxacin and clinafloxacin exhibited the lowest M...

Currently, a standard third-line therapy for Helicobacter pylori (H. pylori) eradication remains to be established. Quinolones show good oral absorption, no major side effects, and marked activity against H. pylori. Several authors have studied quinolone-based third-line therapy and reported encouraging results, with the reported H. pylori cure rates ranging from 60% to 84%. Resistance to quino...

Quinolones were examined for rapid lethal activity against Mycobacterium smegmatis in the presence and absence of chloramphenicol, an inhibitor of protein synthesis. C-8 methoxy, C-6 fluorine, and particular C-7 ring substituents enhanced rapid killing. With the surprising exception of moxifloxacin, higher quinolone concentrations were required for lethal activity in the presence of chloramphen...

Abstract: A series of N-[2-(8-metoxy-2H-chromen-2-one)ethyl] piperazinyl quinolones containing a carbonyl related functional groups (oxo or oxyimino) on the ethyl spacer of coumarin and piperazin rings was synthesized and studied for their antibacterial and antifungal activities . The synthesis of compounds (6a-6l) was achieved through the versatile and efficient synthetic route that involved r...