Search PubMed⌕ Search

Biomedical subjects

T Kikuchi

Publications and source records attributed to T Kikuchi.

At least 775 records · Page 43Linked to original sources
PubMed1975

Studies on fungal polysaccharide. XVII. A new glucuronan "protuberic acid" produced by a fungus Kobayashia nipponica.

A water-soluble glucuronan "protuberic acid", [alpha] 22-D minus 83.6 degrees, was isolated and purified from Kobayashia Nipponica, and its physicochemical properties were investigated. The purified protuberic acid was homogeneous as shown by zone electrophoresis, gel filtration over Sepharose 4B, and ultracentrifugation. The sedimentation coefficient was 1.8 S and its intrinsic viscosity was 1.1 dl/g. By gel filtration the molecular weight was estimated to be about 170 000. The results of periodate oxidation, methylation analysis, and partial acid hydrolysis indicated that this acidic polysaccharide has a linear structure of mainly 1, 4-linkages and containing an acid-labile linkage. Reduced protuberic acid, [alpha] 22-D minus 44 degrees, is also described.

Basidiomycota↗
PubMed1975

[A low response of pituitary growth hormone secretion in the patient with diabetes mellitus after intravenous administration of L-dopa (author's transl)].

Recently, L-dopa has been known as one of drugs to stimulate the secretion of growth hormone from the pituitary gland through dopamine, which is a metabolic of L-dopa, without any changes of serum insulin levels, blood sugar values, fatty acids and amino acids concentrations in the serum of human being. The present study was thus designed to assess the effect of L-dopa on the pituitary gland to secrete the growth hormone in the normal subject and the study was further extended to compare the response of the pituitary secretion of the growth hormone following the administration of L-dopa between in the patient with diabetes mellitus and in the normal subject. In the present experiment, 5 normal subjects and 11 diabetes mellitus without obesity were employed and they received a 30 min infusion of 200 mg L-dopa dissolved in 200 ml physiological saline. In normal subjects, serum growth hormone concentration measured by radio-immunoassay was started to increase within 10 min after L-dopa administration and maximum value of serum growth hormone was obtained 60 min after the drug, mean values of it, 30 ng/ml of serum. Then it was declined sharply upto the values of 2-3 ng/ml. In the patients with diabetes mellitus, on the other hand, maximum value of serum concentration of the growth hormone was only approximately 5 ng/ml of serum obtained between 45 and 75 min after the administration of L-dopa. No changes in the serum concentration of IRI (Immunoreactive insulin) and of blood sugar values were observed by the infusion of L-dopa in both normal subjects and diabetes mellitus. From the above mentioned facts, it was concluded that the ability of pituitary gland to secrete the growth hormone was considerably impaired in diabetics when it was compared with normal subjects.

Adult↗
PubMed1975

Correlation of moth sex pheromone activities with molecular characteristics involved in conformers of bombykol and its derivatives.

Molecular characteristics of bombykol and its 11 derivatives, which reveal significant correlations with biological activities for single sex pheromone receptor cells of four moth species, Bombyx mori, Aglia tau, Endromis versicolora, and Deilephila euphorbiae, were examined on the assumption of the "bifunctional unit model." Probabilities of bifunctional unit formations of those 12 compounds were assessed with frequency distribution patterns of distances between the proton acceptor, the proton donor, and the methyl group involved in a total of 1,200 conformers. A highly significant correlation exists between biological activity for each species and the probability of a particular bifunctional unit formation: a proton acceptor (A)--a methyl group (Me) unit (A--Me distances: about 6 A) for Deilephila (r = 0.94); a proton acceptor (A)--a proton donor (D)(A--D: about 11 A) for Aglia (r = 0.83); two antagonistic proton donor--methyl units (D--Me: about 14 and 5 A for favorable and adverse unit, respectively) for Bombyx (r = 0.94) and Endromis (r = 0.92).

Animals↗