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H Nishihara

Publications and source records attributed to H Nishihara.

At least 91 records · Page 5Linked to original sources
PubMed1979

Malignant melanoma producing serotonin.

A case of malignant melanoma, the tumor of which seems to produce serotonin, is presented. Neither hyperserotoninemia nor carcinoid syndrome was observed in the clinical course. An autopsied sample of the metastatic lung tumor contained a significantly higher concentration (1.35 microgram/g wet weight tissue) of serotonin than that of normal lung (below 0.5 microgram wet wt.). Tryptophan hydroxylase activity, the key enzyme of the biosynthesis of serotonin, was substantial in the same tumor sample when assayed by a sensitive radioisotopic method, supporting the productivity of the amine of the tumor. The ability of melanoma to produce serotonin could be attributed to its neural crest origin.

Adult↗
PubMed1977

Effect of chemical modification of cell surface components of a brewer's yeast on the floc-forming ability.

Effects of treatments with proteolytic enzymes and protein-modifying reagents on flocculation of brewer's yeast IFO 2018 were investigated. The floc-forming ability of the yeast cells was irreversibly eliminated by treatment with papain, trypsin, chymotrypsin or pepsin, indicating that certain proteins on the cell surface participate in the yeast flocculation. Chemical modification with reagents, known to act on disulfide bridges, carboxyl and/or phosphate groups, phenolic groups, amino groups, and imidazole groups, also destroyed the ability to flocculate, although in some cases a high concentration (8 M) of urea was necessary in addition to protein-modifying reagents. Thus, it is suggested strongly that these functional groups of amino acid residues of the proteins are essential for the floc-forming ability of brewer's yeast cells.

Cell Wall↗