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Biomedical subjects

T Furuya

Publications and source records attributed to T Furuya.

At least 235 records · Page 13Linked to original sources
PubMed1988

NAD(P)H-dependent 6'-deoxychalcone synthase activity in Glycyrrhiza echinata cells induced by yeast extract.

The crude extract prepared from Glycyrrhiza echinata cells treated with yeast extract catalyzed the formation of liquiritigenin (5-deoxyflavanone) and isoliquiritigenin (6'-deoxychalcone) in addition to naringenin (5-hydroxyflavanone) when incubated with 4-coumaroyl-CoA and malonyl-CoA in the presence of high concentrations (0.1 mM or higher) of NADPH. Incubation without NADPH, or with low concentrations (0.01 mM or lower), gave only naringenin as a reaction product. With NADH (1 mM), the major product was naringenin accompanied by a small quantity of liquiritigenin. The initial product of the assay with 1 mM NADPH was isoliquiritigenin, indicating a reaction catalyzed by 6'-deoxychalcone synthase (DOCS). Subsequent formation of liquiritigenin was attributed to the presence of chalcone isomerase in the crude extract. The results constitute the first demonstration in vitro of DOCS activity which, in G. echinata cells and other leguminous plants, is involved in the biosynthesis of retrochalcone and 5-deoxyisoflavonoid-derived phytoalexins.

Acyltransferases↗
PubMed1988

Chromosome fragility of lymphocytes from breast cancer patients in relation to epidemiologic data.

The chromosomal fragility of peripheral blood lymphocytes from 50 women, undergoing operations for breast tumors (47 carcinomas, 2 intraductal papillomatoses and 1 malignant lymphoma) was studied to ascertain the association between chromosome fragility and epidemiologic data, such as a family or personal history of cancer, hormonal status, etc. Under conditions of folic acid and thymidine depletion, the average number of gaps and breaks on the patients' lymphocyte chromosome was 6.02 +/- 5.28 and that in the control medium was 2.0 +/- 2.0 while those of healthy controls were 5.8 +/- 5.5 and 1.36 +/- 1.22. These gaps and breaks were mostly seen in group A chromosomes (4.1 +/- 2.6) in 24 patients, including the 2 with benign tumors and the 1 with the lymphoma as well as 11 healthy controls. They were frequent in group B (3.0 +/- 0) in 3 patients, in group C (4.3 +/- 2.9) in 11 patients, and in groups D (2.0 +/- 1.0) and E (3.0 +/- 1.0) in 3 patients from each. This different distribution of gaps and breaks correlated neither with the patients' age nor with their tumor's histology, but patients having a late menarche were distributed in non-A groups. There was low inducibility of breaks in patients with a family history of breast cancer and/or relatively rare cancers. The availability of common fragile sites for studying an individual's susceptibility to cancer is discussed. One patient showed a bromodeoxyuridine-requiring heritable 10q25 fragile site. Another, with triple primary cancers, showed a constitutional translocation of t(5;19)(q15;q13).

Adult↗
PubMed1988

Importance of fatty acid substituents of chemically synthesized lipid A-subunit analogs in the expression of immunopharmacological activity.

The immunopharmacological activities of chemically synthesized lipid A-subunit analogs, 4-O-phosphono-D-glucosamine derivatives carrying different N- and 3-O-linked acyl groups, were investigated. None of the synthetic compounds tested exhibited any detectable pyrogenicity at a dose of 10 micrograms/kg. Weaker lethal toxicity in galactosamine-sensitized mice was detected at 1 microgram per mouse for all the synthetic compounds except GLA-58. Among (RS) stereoisomers of 4-O-phosphono-D-glucosamine derivatives carrying a 3-O-tetradecanoyl (C14) group with different N-linked acyloxyacyl groups, i.e., 3-dodecanoyloxytetradecanoyl [C14-O-(C12)], 3-tetradecanoyloxytetradecanoyl [C14-O-(C14)], and 3-hexadecanoyloxytetradecanoyl [C14-O-(C16)] groups (termed GLA-57, GLA-27, and GLA-58, respectively), GLA-27 exhibited significant colony-stimulating factor-inducing and tumor necrosis factor-inducing activities, mitogenicity, polyclonal B-cell activation activity, macrophage activation, and adjuvanticity. The activities of GLA-57, which had an N-linked C14-O-(C12) group, were equivalent to or somewhat weaker than those of GLA-27 with a C14-O-(C14) group. Significant immunopharmacological activities were not observed for GLA-58, carrying a C14-O-(C16) group bound to the amino group. GLA-59, carrying 3-O-linked 3-hydroxytetradecanoyl (C14OH) and N-linked C14-O-(C14) groups, showed much higher activities than GLA-27, GLA-60, a compound which possesses the same fatty acid substituents as GLA-59 but with reversed binding sites, showed the strongest B-cell activation and adjuvant activities among the synthetic compounds. Among stereoisomers of GLA-59 and GLA-60 composed of fatty acid substituents with the (RR) and (SS) configuration, compounds with the (RR) configuration elicited stronger activities than the (SS) stereoisomers. The importance of fatty acid substituents, including stereospecificity for the expression of immunopharmacological activities of 4-O-phosphono-D-glucosamine derivatives, was demonstrated.

Adjuvants, Immunologic↗
PubMed1986

Stereoselectivity of a potent calcium antagonist, 1-benzyl-3-pyrrolidinyl methyl 2,6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Four enantiomers (3a-d) of the title compound, YM-09730 (3), were synthesized by the reaction of (-)- or (+)-5-(methoxycarbonyl)-2, 6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid (1a or 1b) with (S)- or (R)-1-benzyl-3-pyrrolidinol (2a or 2b). [3H]Nitrendipine binding affinity and coronary vasodilating activity of these compounds were evaluated. The absolute configuration of the most potent enantiomer (3a) with the longest duration was unequivocally determined to be (S)-1,4-dihydropyridine-C4 and (S)-pyrrolidine-C3 (S,S) by X-ray crystallographic study on 3a X HBr as well as 3a X HCl. The configuration of 1a corresponds to R, and the other enantiomers of 3 were respectively determined by chemical correlation. The potency order of the four enantiomers was (S,S)-3a greater than (S,R)-3b greater than (R,R)-3d greater than (R,S)-3c. Latent chiral characters of nifedipine derivatives with the identical ester groups were assigned by comparison of their puckering modes of 1,4-dihydropyridine (DHP) rings with those found in 3a X HCl or 3a X HBr. On the basis of the assignment, it has been revealed that the (S)-DHP nifedipine derivatives possess the synperiplanar carbonyl group at C5. The conformational restriction may be a factor causing stereoselectivity of antagonism.

Animals↗
PubMed1986

Acid beta-galactosidase from human fibroblasts. A microscale purification method monitored by a highly sensitive enzyme assay.

A highly sensitive microassay method and a microscale purification system were developed to isolate the residual acid beta-galactosidase in GM1-gangliosidosis fibroblasts. The sensitivity of the microassay system, composed of a 96-well microplate and a microplate fluorometer, was 100-fold higher than that of the conventional system and the response was linear in the pmole range. Acid beta-galactosidase was characterized as a thiol enzyme which was inactivated by a mercuric compound. This enzyme was completely adsorbed on an Hg-agarose column and was easily eluted from the column by 10 mM 2-mercaptoethanol. The microscale purification system using Con A-Sepharose, PAT-Sepharose, and Hg-agarose column chromatography achieved 565- and 7,970-fold purifications of acid beta-galactosidase with an overall yields of 44% and 45% from normal and GM1-gangliosidosis fibroblasts, respectively. The purified enzyme fractions did not contain any other lysosomal enzyme activities except for a small amount of beta-N-acetylhexosaminidase activity.

Chromatography, Agarose↗
PubMed1986

Short-term toxicity study of 4-dimethylaminoazobenzene in marmosets.

The marmoset, a small non-human primate, has rarely been used in toxicological studies. A short-term toxicity study was performed on common marmosets (BW = 330 +/- 32 g). Fifteen male marmosets received oral administration of DAB at a dose level of 56 mg/kg/day and 4 control animals received corn oil alone for a period of 15 days. Hematological, biochemical, histopathological and bone marrow examinations were carried out on the 5th, 10th and 15th day of treatment. Body weight decreased continuously and two animals died on day 10. Decreases in RBC, Hb and Ht and increases in MCV and WBC were observed. Uric acid and glucose were increased and AlP and LAP were decreased. Aldolase, GOT and GPT were increased by day 10, and thereafter recovery of aldolase to the control level and decreases of GOT and GPT were observed. Relative organ weights of the liver, kidney, spleen and adrenal were increased. Histologically, C-cell hyperplasia of the thyroid and slight changes of the liver were noted. Marrow total cell counts were not changed, but the G/E ratio was reduced. Thus, macrocytic anemia, an increase of marrow erythroblasts due to anemia and changes of biochemical parameters indicating liver injury were observed in marmosets; these findings were similar to those in rats in the previous experiments.

Administration, Oral↗