Shigeko Sakai

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This study was carried out to evaluate the potential of aminated gelatin as a nasal absorption enhancer for peptide drugs. The absorption-enhancing effect was investigated in rats using insulin and fluorescein isothiocyanate-dextran with a molecular weight of 4.4 kDa (FD-4) as model drugs. The absorption of insulin was estimated by measuring the changes in(More)
The objective of this study was to compare protonation equilibrium and lipophilicity of two quinolone antibacterials, grepafloxacin (GPFX) and ciprofloxacin (CPFX), in order to give an insight into effects on the physicochemical properties by slight structural motifs. The protonation equilibrium was investigated by a spectrophotometry. Macro- and(More)
The purpose of this study was to investigate the distribution of Grepafloxacin (GPFX), a new quinolone antimicrobial agent, in the lung epithelial lining fluid (ELF) and the alveolar macrophage (AM) in rats, which are potential infection sites in respiratory tract infections. We also aimed to clarify the mechanism governing the transferability of GPFX into(More)
This study was performed to characterize the protonation equilibrium at the molecular level and pH-dependent lipophilicity of olamufloxacin. The deprotonation fraction of the carboxyl group as a function of pH was specifically calculated at the critical wavelength 294 nm, where UV pH-dependent absorbance of olamufloxacin was independent of the ionized state(More)
A cytokinin-binding protein (CBP) was purified from a crude extract of etiolated mung bean seedlings by a protocol involving affinity chromatography on benzyladenine-linked Sepharose 4B, ion exchange chromatography on DEAE-Sephadex A50, and gel filtration on Sphacryl S-400. The molecular weight was estimatd to be about 200,000 by gel filtration. CBP(More)
The aminopropyl-silicate-titanate hybrid membrane was successfully synthesized onto a Ca-alginate gel bead by the sol-gel method, from two kinds of organometallic compound precursors, tetraethyl orthotitanate (TEOTi) [Ti(OC2H5)4] and 3-aminopropyltrimethyl orthosilicate (APTrMOS) [(CH3O)3Si(CH2)3NH2]. APTrMOS acted as a binding agent between inorganic(More)
A diterpenoid, totarol (1), fromPodocarpus nagi was evaluated as an antioxidant. This diterpenoid inhibited autoxidation of linoleic acid. Mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH were also inhibited. Nagilactone E (2), a norditerpene lactone isolated from the same source, had no antioxidative(More)
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