noroxin medication guide
Bacteriostatic and bactericidal effects of three fluoroquinolones, norfloxacin, ofloxacin and pefloxacin, against 320 strains of Gram-negative bacilli were studied in vitro. For nalidixic acid-susceptible Enterobacteriaceae, susceptibility or resistance to second or third generation cephalosporins has no significant bearing on the MIC 90 of each of the three antibiotics. This is not so of nalidixic acid-resistant strains. All E. coli and K. pneumoniae strains are susceptible to the three quinolones (MIC 90 less than 3 mg/1); MICs 90 are higher for E. cloacae and S. marcescens; Serratia strains in particular have an MIC 90 greater than 6 mg/1. Nalidixic acid-susceptible Acinetobacter strains can be eliminated by ofloxacin or pefloxacin, whereas norfloxacin has the greatest activity against P. aeruginosa. We conclude that when multiresistant bacteria emerge, testing of susceptibility to the three quinolones studied may be useful.
A rapid, accurate and sensitive method has been developed for the quantitative determination of four fluoroquinolone antimicrobial agents, enoxacin, norfloxacin, ofloxacin and ciprofloxacin, with high in-vitro activity against a wide range of Gram-negative and Gram-positive organisms.A Kromasil 100 C(8) 250 mm x 4 mm, 5 microm analytical column was used with an eluting system consisting of a mixture of CH(3)CN-CH(3)OH-citric acid 0.4 mol L(-1) (7:15:78 %, v/v). Detection was performed with a variable wavelength UV-visible detector at 275 nm resulting in limits of detection: 0.02 ng per 20 microL injection for enoxacin and 0.01 ng for ofloxacin, norfloxacin and ciprofloxacin. Hydrochlorothiazide (HCT) was used as internal standard at a concentration of 2 ng microL(-1). A rectilinear relationship was observed up to 2 ng microL(-1) for enoxacin, 12 ng microL(-1) for ofloxacin, 3 ng microL(-1) for norfloxacin, and 5 ng microL(-1) for ciprofloxacin. Separation was achieved within 10 min. The statistical evaluation of the method was examined by performing intra-day (n=8) and inter-day precision assays (n=8) and was found to be satisfactory with high accuracy and precision. The method was applied to the direct determination of the four fluoroquinolones in human blood serum. Sample pretreatment involved only protein precipitation with acetonitrile. Recovery of analytes in spiked samples was 97+/-6% over the range 0.1-0.5 ng microL(-1).
Thirty-four isolates of Pseudomonas pseudomallei were tested by a broth microdilution technique for susceptibility to amifloxacin, ciprofloxacin, enoxacin, norfloxacin, and ofloxacin. Ciprofloxacin was the most active agent tested, with an MIC for 90% of the strains tested of 8 micrograms/ml. These in vitro results suggest that the fluoroquinolones tested would not be optimal for therapy of melioidosis.
noroxin generic name
Recent observations have suggested that classic antibiotics kill bacteria by stimulating the formation of reactive oxygen species (ROS). If true, this notion might guide new strategies to improve antibiotic efficacy. In this study, the model was directly tested. Contrary to the hypothesis, antibiotic treatment did not accelerate the formation of hydrogen peroxide in Escherichia coli and did not elevate intracellular free iron, an essential reactant for the production of lethal damage. Lethality persisted in the absence of oxygen, and DNA repair mutants were not hypersensitive, undermining the idea that toxicity arose from oxidative DNA lesions. We conclude that these antibiotic exposures did not produce ROS and that lethality more likely resulted from the direct inhibition of cell-wall assembly, protein synthesis, and DNA replication.
noroxin 500 mg
The pharmacokinetics of the new fluoroquinolone derivatives have been extensively studied in patients with various degrees of chronic renal insufficiency during the last few years. Their kinetic profiles depend on the elimination pathways and on the degree of metabolic transformation. Renal insufficiency does not significantly modify pefloxacin kinetics. For the other new quinolones, a decrease in glomerular filtration rate below 20-30 ml/min induces an increase in terminal half-life and a decrease in plasma and renal clearance, related to the degree of renal impairment. These drugs are poorly removed by haemodialysis. Dosage adjustments are required, particularly in severe renal failure and for the drugs almost exclusively excreted, in unchanged form, via the renal route.
In the present paper, p-octacarboxyphenylazocalixarene (CPAC) was used as supramolecular probe according to a reported method. The interaction of CPAC with drug norfloxacin (NFLX) was studied by fluorescence spectrometry. The results show that CPAC can strongly quench the fluorescence of NFLX because of the complex interaction between host and guest molecules in exo-inclusion complex. The spectral changes indicated that the quenching can be considered as static quenching mode. The hydrophobic interaction between the cavity of CPAC and the quinoline ring was the main force to consolidate the exo-inclusive complex CPAC-NFLX stability. The complex constant (K) and binding ratio (n) were determined to be 6. 38 X 10(5) L x mol(-1) and 1, respectively. Further experiment found that the calf thymus DNA and CPAC can combine, leading to the release of NFLX and the enhancement of fluorescence of the reaction system. It is expected that CPAC will be used as drug carrier and releaser.
noroxin brand name
We administered norfloxacin (NFLX) to 16 children aged 3 to 14 year-old at the dose of 5.2 to 17.2 mg/kg/day. We evaluated the efficacy and safety of NFLX in 6 children with respiratory tract infections, 8 urinary tract infections, and 2 gastrointestinal tract infections. Efficacy rate of NFLX was 93.8% and eradicated rate was 92.9%. Any adverse effects were not observed. These results suggested that NFLX could be used safely to the children.
To characterize mechanisms of resistance to fluoroquinolones by Mycobacterium tuberculosis, mutants of strain H37Ra were selected in vitro with ofloxacin. Their quinolone resistance-determining regions for gyrA and gyrB were amplified and sequenced to identify mutations in gyrase A or B. Three types of mutants were obtained: (i) one mutant (TKp1) had no mutations in gyrA or gyrB; (ii) mutants that had single missense mutations in gyrA, and (iii) mutants that had two missense mutations resulting in either two altered gyrase A residues or an altered residue in both gyrases A and B. The TKp1 mutant had slightly reduced levels of uptake of [14C]norfloxacin, which was associated with two- to fourfold increases in the MICs of ofloxacin, ciprofloxacin, and sparfloxacin. Gyrase mutations caused a much greater increase in the MICs of fluoroquinolones. For mutants with single gyrA mutations, the increases in the MICs were 4- to 16-fold, and for mutants with double gyrase mutations, the MICs were increased 32-fold or more compared with those for the parent. A gyrA mutation in TKp1 secondary mutants was associated with 32- to 128-fold increases in the MICs of ofloxacin and ciprofloxacin compared with the MICs for H37Ra and an eight-fold increase in the MIC of sparfloxacin. Sparfloxacin was the most active fluoroquinolone tested. No sparfloxacin-resistant single-step mutants were selected at concentrations of > 2.5 micrograms/ml, and high-level resistance (i.e., MIC, > and = 5 micrograms/ml) was associated with two gyrase mutations. Mutations in gyrB and possibly altered levels of intracellular accumulation of drug are two additional mechanisms that may be used by M. tuberculosis in the development of fluoroquinolone resistance. Because sparfloxacin is more active in vitro and selection of resistance appears to be less likely to occur, it may have important advantage over ofloxacin or ciprofloxacin for the treatment of tuberculosis.
noroxin norfloxacin generic
Various kinds of antibiotics, especially fluoroquinolone antibiotics (FQs) have been widely used for the therapy of infectious diseases in human and livestock. For their poorly absorbed by living organisms, large-scale misuse or abuse of FQs will foster drug resistance among pathogenic bacteria, as well as a variety of environmental problems when they were released in the environment. In this work, the adsorption properties of two FQs, namely norfloxacin (NOR) and ciprofloxacin (CIP), by nano-hydroxyapatite (n-HAP) were studied by batch adsorption experiments. The adsorption curves of FQs by n-HAP were simulated by Langmuir and Freundlich isotherms. The results shown that NOR and CIP can be adsorbed effectively by the adsorbent of n-HAP, and the adsorption capacity of FQs increase with increasing dosage of n-HAP. The optimum dosage of n-HAP for FQs removal was 20 g · L(-1), in which the removal efficiencies is 51.6% and 47.3%, and an adsorption equilibrium time is 20 min. The maximum removal efficiency occurred when pH is 6 for both FQs. The adsorption isotherm of FQs fits well for both Langmuir and Freundlich equations. The adsorption of both FQs by n-HAP follows second-order kinetics.