Shinya Kataoka

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The methanolic extract from the rhizomes of Paris polyphylla SM. var. yunnanensis (FR.) H-M. was found to potently inhibit ethanol-induced gastric lesions in rats. Through bioassay-guided separation, four known spirostanol-type steroid saponins, pennogenin 3-O-alpha-L-rhamnopyranosyl(1-->2)-[alpha-L-arabinofuranosyl(1-->4)]-beta-D-glucopyranoside (1),(More)
The 80% aqueous acetone extract from the rhizomes of Alpinia galanga showed nitric oxide (NO) production inhibitory activities in mouse peritoneal macrophages. From the aqueous acetone extract, three new 8-9' linked neolignans, galanganal, galanganols A and B, and a sesquineolignan, galanganol C, were isolated together with nine known phenylpropanoids and(More)
The proliferation of vascular smooth muscle cells has been implicated as a causative factor in atherogenesis. Calcium channel blockers have been shown to retard the progression of atherosclerosis. To elucidate the mechanism by which these drugs mediate such actions, we studied the effects of a new calcium antagonist, clentiazem, on the in vitro(More)
1'S-1'-Acetoxychavicol acetate from the rhizomes of Alpinia galanga inhibited nitric oxide (NO) production in lipopolysaccharide-activated mouse peritoneal macrophages with an IC(50) value of 2.3 microM. To clarify the structure-activity relationship of 1'S-1'-acetoxychavicol acetate, various natural and synthetic phenylpropanoids and synthetic(More)
BACKGROUND AND PURPOSE The mechanism by which calcium antagonists (CAs) inhibit proliferation in vascular smooth muscle cells (VSMCs) is not yet fully understood. We investigated the effects of four CAs (clentiazem, verapamil, diltiazem, and nifedipine) on signal transduction pathways activated by platelet-derived growth factor (PDGF). To determine these(More)