Gatifloxacin

Fluoroquinolone antibiotic. Inhibits bacterial type II topoisomerases (IC₅₀ values are 0.109 and 13.8 μg/ml for E.coli DNA gyrase and S.aureus topoisomerase IV respectively). Displays potent activity against gram-positive and

Besifloxacin Ophthalmic Suspension 0.6% Compared with Gatifloxacin Ophthalmic Solution 0.3% for the Treatment of Bacterial Conjunctivitis in Neonates.[Pubmed:28078599]

Drugs R D. 2017 Mar;17(1):167-175.

PURPOSE: The aim of this study was to evaluate the safety and efficacy of topical besifloxacin ophthalmic suspension 0.6% compared with Gatifloxacin ophthalmic solution 0.3% in the treatment of bacterial conjunctivitis in neonates. METHODS: This was a multicenter, randomized, double-masked, parallel group study. Subjects /=1 (scale 0-3) for both conjunctival discharge and conjunctival hyperemia were randomized to besifloxacin or Gatifloxacin instilled three times daily for 7 days, and completed five study visits (three clinic visits and two phone calls). Primary endpoints included clinical resolution (absence of both conjunctival discharge and conjunctival hyperemia) at visit 5 (day 8 or 9) and ocular and non-ocular treatment-emergent adverse events (AEs). Bacterial eradication was a secondary endpoint. RESULTS: Thirty-three subjects were included in the intent-to-treat (ITT) population. All were aged <28 days, with a mean (standard deviation) age of 15.5 days (6.0), and 57.6% were female. Twenty-two subjects had culture-confirmed conjunctivitis in at least one eye (modified ITT [mITT] population), most often with Gram-positive bacteria. Visit 5 clinical resolution and bacterial eradication rates were comparable among besifloxacin- and Gatifloxacin-treated study eyes (clinical resolution: 12/16 [75.0%] vs. 12/17 [70.6%] for the ITT population, and 11/13 [84.6%] vs. 7/9 [77.8%] for the mITT population; bacterial eradication: 12/13 [92.3%] vs. 8/9 [88.9%] for the mITT population, respectively). No AEs were reported in the besifloxacin treatment group, and AEs reported in the Gatifloxacin group were considered not treatment-related. CONCLUSIONS: In this small study in neonates, both besifloxacin and Gatifloxacin appeared effective and safe in the treatment of bacterial conjunctivitis. Larger studies are warranted.

Surface-modified gatifloxacin nanoparticles with potential for treating central nervous system tuberculosis.[Pubmed:28331318]

Int J Nanomedicine. 2017 Mar 13;12:1959-1968.

A new nanocarrier is developed for the passage of Gatifloxacin through the blood-brain barrier to treat central nervous system tuberculosis. Gatifloxacin nanoparticles were prepared by nanoprecipitation using poly(lactic-co-glycolic acid) (PLGA) 502 and polysorbate 80 or Labrafil as surface modifiers. The evaluation of in vivo blood-brain barrier transport was carried out in male Wistar rats using rhodamine-loaded PLGA nanoparticles prepared with and without the surface modifiers. At 30 and 60 minutes after administration, nanoparticle biodistribution into the brain (hippocampus and cortex), lungs, and liver was studied. The results obtained from the cerebral cortex and hippocampus showed that functionalization of rhodamine nanoparticles significantly increased their passage into the central nervous system. At 60 minutes, rhodamine concentrations decreased in both the lungs and the liver but were still high in the cerebral cortex. To distinguish the effect between the surfactants, Gatifloxacin-loaded PLGA nanoparticles were prepared. The best results corresponded to the formulation prepared with polysorbate 80 with regard to encapsulation efficiency (28.2%), particle size (176.5 nm), and zeta-potential (-20.1 mV), thereby resulting in a promising drug delivery system to treat cerebral tuberculosis.

Simultaneous quantification of gatifloxacin, moxifloxacin, and besifloxacin concentrations in cornea and aqueous humor by LC-QTOF/MS after topical ocular dosing.[Pubmed:27670369]

J Pharmacol Toxicol Methods. 2017 Jan - Feb;83:87-93.

The fourth-generation fluoroquinolones are widely used as ophthalmic antimicrobials. This study aimed to validate a new analytical technique for simultaneous quantification of Gatifloxacin, moxifloxacin, and besifloxacin concentrations in the cornea and aqueous humor by liquid chromatography (LC) coupled to quadrupole time-of-flight mass spectrometry (QTOF/MS) at 10min and 1h after instillation of topical ophthalmic antimicrobial suspensions. It was used twenty-two male dogs without ocular lesions verified by ophthalmic and histologic examinations. Methanol:water (4:1) was used for the extraction procedure for cornea and acetonitrile:water (4:1) was used for aqueous humor. The chromatographic separations were carried out on a C18 column with a linear gradient of water and methanol, both containing 0.1% formic acid. The total chromatographic run time was 4min. Mass spectrometry analyses were performed on a Xevo G2-S QTof tandem mass spectrometer, operated in a positive ion electrospray ionization (ESI+) mode. The retention times were approximately 1.42min for Gatifloxacin, 1.87min for moxifloxacin, and 3.01min for besifloxacin. No interference peak was detected for the three tested antimicrobials in samples obtained from both cornea and aqueous humor, ensuring that the peak response was exclusive to the analyte of interest. The limit of detection for the three antimicrobials was 0.11mug/mL and the limit of quantification was 0.42mug/mL for both cornea and aqueous humor samples. At both time points post instillation of the three antimicrobials, moxifloxacin had the highest corneal concentration and besifloxacin demonstrated the highest concentration in the aqueous humor.

High-throughput screening assay for the identification of compounds regulating self-renewal and differentiation in human embryonic stem cells.[Pubmed:18522853]

Cell Stem Cell. 2008 Jun 5;2(6):602-12.

High-throughput screening (HTS) of chemical libraries has become a critical tool in basic biology and drug discovery. However, its implementation and the adaptation of high-content assays to human embryonic stem cells (hESCs) have been hampered by multiple technical challenges. Here we present a strategy to adapt hESCs to HTS conditions, resulting in an assay suitable for the discovery of small molecules that drive hESC self-renewal or differentiation. Use of this new assay has led to the identification of several marketed drugs and natural compounds promoting short-term hESC maintenance and compounds directing early lineage choice during differentiation. Global gene expression analysis upon drug treatment defines known and novel pathways correlated to hESC self-renewal and differentiation. Our results demonstrate feasibility of hESC-based HTS and enhance the repertoire of chemical compounds for manipulating hESC fate. The availability of high-content assays should accelerate progress in basic and translational hESC biology.

Antibacterial activity of gatifloxacin (AM-1155, CG5501, BMS-206584), a newly developed fluoroquinolone, against sequentially acquired quinolone-resistant mutants and the norA transformant of Staphylococcus aureus.[Pubmed:9687384]

Antimicrob Agents Chemother. 1998 Aug;42(8):1917-22.

Alternate mutations in the grlA and gyrA genes were observed through the first- to fourth-step mutants which were obtained from four Staphylococcus aureus strains by sequential selection with several fluoroquinolones. The increases in the MICs of Gatifloxacin accompanying those mutational steps suggest that primary targets of Gatifloxacin in the wild type and the first-, second-, and third-step mutants are wild-type topoisomerase IV (topo IV), wild-type DNA gyrase, singly mutated topo IV, and singly mutated DNA gyrase, respectively. Gatifloxacin had activity equal to that of tosufloxacin and activity more potent than those of norfloxacin, ofloxacin, ciprofloxacin, and sparfloxacin against the second-step mutants (grlA gyrA; Gatifloxacin MIC range, 1.56 to 3.13 microg/ml) and had the most potent activity against the third-step mutants (grlA gyrA grlA; Gatifloxacin MIC range, 1.56 to 6.25 microg/ml), suggesting that Gatifloxacin possesses the most potent inhibitory activity against singly mutated topo IV and singly mutated DNA gyrase among the quinolones tested. Moreover, Gatifloxacin selected resistant mutants from wild-type and the second-step mutants at a low frequency. Gatifloxacin possessed potent activity (MIC, 0.39 microg/ml) against the NorA-overproducing strain S. aureus NY12, the norA transformant, which was slightly lower than that against the parent strain SA113. The increases in the MICs of the quinolones tested against NY12 were negatively correlated with the hydrophobicity of the quinolones (correlation coefficient, -0.93; P < 0.01). Therefore, this slight decrease in the activity of Gatifloxacin is attributable to its high hydrophobicity. Those properties of Gatifloxacin likely explain its good activity against quinolone-resistant clinical isolates of S. aureus harboring the grlA, gyrA, and/or norA mutations.

Inhibitory activities of gatifloxacin (AM-1155), a newly developed fluoroquinolone, against bacterial and mammalian type II topoisomerases.[Pubmed:9756776]

Antimicrob Agents Chemother. 1998 Oct;42(10):2678-81.

We determined the inhibitory activities of Gatifloxacin against Staphylococcus aureus topoisomerase IV, Escherichia coli DNA gyrase, and HeLa cell topoisomerase II and compared them with those of several quinolones. The inhibitory activities of quinolones against these type II topoisomerases significantly correlated with their antibacterial activities or cytotoxicities (correlation coefficient [r] = 0.926 for S. aureus, r = 0.972 for E. coli, and r = 0.648 for HeLa cells). Gatifloxacin possessed potent inhibitory activities against bacterial type II topoisomerases (50% inhibitory concentration [IC50] = 13.8 microg/ml for S. aureus topoisomerase IV; IC50 = 0.109 microg/ml for E. coli DNA gyrase) but the lowest activity against HeLa cell topoisomerase II (IC50 = 265 microg/ml) among the quinolones tested. There was also a significant correlation between the inhibitory activities of quinolones against S. aureus topoisomerase IV and those against E. coli DNA gyrase (r = 0.969). However, the inhibitory activity against HeLa cell topoisomerase II did not correlate with that against either bacterial enzyme. The IC50 of Gatifloxacin for HeLa cell topoisomerase II was 19 and was more than 2,400 times higher than that for S. aureus topoisomerase IV and that for E. coli DNA gyrase. These ratios were higher than those for other quinolones, indicating that Gatifloxacin possesses a higher selectivity for bacterial type II topoisomerases.

Gatifloxacin (AM-1155; BMS-206584; PD135432) is a potent fluoroquinolone antibiotic with broad-spectrum antibacterial activity. Gatifloxacin inhibits bacterial type II topoisomerases (IC50=13.8 μg/ml for S. aureus topoisomerase IV) and E. coli DNA gyrase (IC50=0.109 μg/ml). Gatifloxacin can be used to treat bacterial conjunctivitis in vivo.

Gatifloxacin,112811-59-3,AM 1155,Natural Products,Topoisomerase, buy Gatifloxacin , Gatifloxacin supplier , purchase Gatifloxacin , Gatifloxacin cost , Gatifloxacin manufacturer , order Gatifloxacin , high purity Gatifloxacin