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S Yasuno

Publications and source records attributed to S Yasuno.

5 recordsLinked to original sources
PubMed1999

New method for determining the sugar composition of glycoproteins, glycolipids, and oligosaccharides by high-performance liquid chromatography.

A new method is reported that can be performed within a single vessel to analyze the composition of aldose, hexosamine, and sialic acid residues of glycoproteins, glycolipids, and oligosaccharides. Glycoconjugates are treated with sialidase or subjected to mild acid hydrolysis, before being treated with N-acetylneuraminic acid aldolase to convert the free sialic acid residues to their corresponding N-acylmannosamines. The reaction mixture is then successively subjected to acid hydrolysis (in order to produce monosaccharides), N-acetylation, and conversion with p-aminobenzoic acid ethyl ester (ABEE). The ABEE-converted monosaccharides are simultaneously determined by reverse-phase high-performance liquid chromatography. Determination of the sugar compositions of bovine fetuin, II3NeuGc alpha-LacCer, and 3'-sialyllactose with this method was found to be highly accurate. Linearity of the peak area vs. the amount of bovine fetuin ranged from 1 to 50 micrograms in all ABEE-converted monosaccharides. With a slight modification to this method, sialic acid residues can be separately determined as NeuAc and NeuGc. This novel method and its modified version are used to demonstrate the sugar compositions of alpha 1-acid glycoproteins from several sources.

Acetylation↗
PubMed1997

A new method for studying the binding of human IgE to CD23 and the inhibition of this binding.

CD23, a low-affinity receptor for IgE (Fc epsilonRII), is a type II membrane-bound glycoprotein expressed on many hematopoietic cells, particularly activated B-cells. CD23 binds to IgE at a domain homologous to Ca2+-dependent (C-type) animal lectin. This paper describes a binding assay by which only the specific binding of IgE to CD23 expressed on Epstein-Barr virus (EBV)-transformed B-cell line, L-KT9 cells, can be detected. This assay is useful in the search for CD23 ligands among many chemical compounds, because it is easily carried out and does not require the use of any radiolabeled reagents. Using the assay, we investigated the inhibition of IgE binding to CD23 by fucose-1-phosphate which has been reported to inhibit the binding of sCD23 to IgE [Delespesse, G., Sarfati, M., Wu, C.Y., Fournier, S., Letellier, M., 1992. The low affinity receptor for IgE. Immunol. Rev. 125, 77.] and the binding of CD23 to CD21 [Pochon, S., Graber, P., Yeager, M., Jansen, K., Bernard, A.R., Aubry, T.-P., Bonnefoy, J.-Y., 1992. Demonstration of second ligand for the low affinity receptor for immunoglobulin E (CD23) using recombinant CD23 reconstituted into flourescent liposomes. J. Exp. Med. 176, 389.]. Although both alpha- and beta-L-fucose-l-phosphate/di(cyclohexylammonium) salt decreased the extent of IgE binding to CD23, the inhibitory effects were not due to alpha- or beta-L-fucose-1-phosphate but to cyclohexylamine. The inhibitory effect of cyclohexylamine was dose dependent and the effect was decreased when inhibition tests were carried out in the presence of a 10-fold excess of IgE. These results suggest that cyclohexylamine specifically interacts with the binding of CD23 and IgE.

B-Lymphocytes↗
PubMed1966

[Diabetic coma].

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Diabetic Coma↗