Publications by authors named "Kouhei Ohya"

Gonorrhea has become a serious problem because the number of infected people is increasing and the multi-drug resistance of the causative bacteria, Neisseria gonorrhoeae, is progressing. To develop novel drugs against resistant N. gonorrhoeae, we focused on the antibiotic novobiocin (1).

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The present study aimed to clarify the mechanism underlying the high distribution of lascufloxacin in epithelial lining fluid (ELF). Involvement of transporters was examined by transcellular transport across Calu-3 and transporter-overexpressing cells; the binding of lascufloxacin to ELF components was examined by an organic solvent-water partitioning system that employed pulmonary surfactant and phospholipids. Transcellular transport across the transporter-overexpressing cells indicated lascufloxacin to be a substrate of both P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP); therefore, its transport across Calu-3 cells was inhibited by P-gp and BCRP inhibitors.

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Background: Serum urate (SUA) level is affected by alteration in urinary reabsorption caused by clinically important drugs; however, there are no experimental models suitable to assess their effect on renal reabsorption. We, therefore, aimed to establish an experimental system co-expressing the urate transporters URAT1 (SLC22A12) and URATv1 (SLC2A9) (designated UUv cells) at the apical and basolateral membranes, respectively.

Methods: Apical uptake and vectorial transport of [(14)C]urate in the apical-to-basolateral direction in UUv cells were measured in the presence or absence of uricosuric benzbromarone or anti-uricosuric trans-stimulators.

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