Publications by authors named "Shiro Nagai"

Innate immunity is a universal prophylactic system which all multi-cellular animals possess. Macrophages are the cells that play the central role in the innate immune system. In 1991, we discovered a substance in a water extract of wheat flour that activated macrophages after oral or intradermal administration.

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Background: Lipopolysaccharide (LPS), a major component of the cell walls of Gram-negative bacteria, was one of the main components of Coley's vaccine and is known to have strong adjuvanticity. Though it is known that LPS exists in the digestive tract of organisms, the biological significance for the organism has not been clarified. In this study, the correlation between the structure and function of LPS was determined using acetic acid bacteria.

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Citrinin produced by Aspergillus, Penicillium, and Monascus species is a polyketide compound that has nephrotoxic activity in mammals and is bactericidal toward gram-positive bacteria. To avoid the risk of citrinin contamination in other fermentation products produced by Monascus purpureus, knowledge of the citrinin biosynthetic genes is needed so that citrinin-nonproducing strains can be generated. We cloned a polyketide synthase (PKS) gene from M.

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A micellar electrokinetic chromatography (MEKC) method was developed for estimating the angiotensin-I converting enzyme (ACE) inhibitory activity by separating the hippuric acid liberated in the ACE reaction mixture in the presence of an inhibitor, captopril. The hippuric acid was successfully separated and detected by MEKC with a 25 mM sodium dodecyl sulfate solution in a 25 mM phosphate-50 mM borate buffer at pH 7.0; the total analysis took about 5 min.

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