Twenty μL of reaction mixture containing 0.4 μg of kinetoplast DNA with 1 U of topoisomerase II and serial dilutions of each antibacterial agent (including Flumequine) are incubated for 5 min at 37°C in buffer containing 20 mM Tris-HCl (pH 7.5), 120 mM KCl, 10 mM MgCl₂, 1 mM ATP, 0.5 mM dithiothreitol, and 30 μg/mL of bovine serum albumin. After stopping the reaction by adding sarcosyl with gel-loading buffer, catenated and decatenated kDNAs are separated by agarose gel electrophoresis. The gels are stained with ethidium bromide and photographed using UV light (302 nm) with a Gel Print 200i/VGA, and the brightness of bands is traced with an Image Analyzer. Each band is quantified and the amount of DNA treated with each concentration of quinolone is measured to determine the 50% inhibitory concentration against DNA gyrase and topoisomerase II^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

The Chinese hamster lung cell line CHL/IU is routinely maintained in monolayer culture in Dulbecco's modified MEM medium supplemented with 10% fetal bovine serum at 37°C under a 5% CO₂ atmosphere. Exponentially growing cells are treated with Flumequine dissolved in DMSO for 1 h. The dose range is chosen in order to obtain both damaged and highly damaged cells. Following Flumequine treatment, cells are embedded in GP42 agarose dissolved in saline at 1%. Cell number and cell viability are determined for each dose^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Infant and young-adult male ddY mice at 4 and 7 weeks of age, respectively, are used after 1 week of acclimatization. Groups are treated once orally with Flumequine at <500 mg/kg. Adult mice are sacrificed at 3 and 24 h after treatment, and 8 organs, the stomach, colon, liver, kidney, urinary bladder, lung, brain, and bone marrow, are removed. Infant mice are sacrificed 3 and 24 h after treatment, and the livers are excised. In another study, the genotoxicity of Flumequine is studied in the regenerating liver of adult mice. For this purpose, male mice at 8 weeks-of-age are anesthetized with ether and 3 major lobes of the liver, left lateral lobe, left medial lobe, and right lateral lobe, are removed. Four days after the hepatectomy, mice are subjected to oral administration of Flumequine once. They are sacrificed 3 h after FL-treatment and regenerated livers are sampled. Slides for the comet assay are prepared at each set time^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Kashida Y, et al. Mechanistic study on flumequine hepatocarcinogenicity focusing on DNA damage in mice. Toxicol Sci. 2002 Oct;69(2):317-21.

  [2]. Aller-Morán LM, et al. Evaluation of the in vitro activity of flumequine against field isolates of Brachyspira hyodysenteriae. Res Vet Sci. 2015 Dec;103:51-3.

  [3]. Giraud E, et al. Mechanisms of quinolone resistance and clonal relationship among Aeromonas salmonicida strains isolated from reared fish with furunculosis. J Med Microbiol. 2004 Sep;53(Pt 9):895-901.

261.25

C₁₄H₁₂FNO₃

42835-25-6

O=C(C1=CN2C(C)CCC3=C2C(C1=O)=CC(F)=C3)O

Room temperature in continental US; may vary elsewhere