Search PubMed⌕ Search

Biomedical subjects

S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 1,423 records · Page 79Linked to original sources
PubMed1979

Inhibition of factor VIII-associated platelet aggregation by heparin and dextran sulfate, and its mechanism.

Both ristocetin-induced aggregation in the presence of human factor VIII and bovine factor VIII-induced aggregation of washed normal human platelets were inhibited or reversed by the addition of heparin or dextran sulfate. These actions of dextran sulfate were stronger than those of heparin, and dependent on the sulfur content of dextran sulfate. In order to study the mechanism of actions of dextran sulfate and heparin, the affinity chromatographic experiment of factor VIII in human and bovine plasma, respectively, was carried out by using a dextran sulfate- and a heparin-Agarose column. Both human and bovine factor VIII have a strong affinity for dextran sulfate with high sulfur content and a weak affinity for heparin, but no affinity for dextran sulfate with low sulfur content. From these results, it is suggested that dextran sulfate or heparin binds directly the human and bovine factor VIII, which is an essential factor for the maintenance of the weak interplatelet bonds, and either inhibits or reverses the platelet aggregation.

Chromatography, Affinity↗
PubMed1979

Stimulation of cholesterol esterification in hepatic microsomes by lipoproteins from normal and hypercholesterolemic rabbit serum.

Incubation of plasma lipoproteins with rabbit hepatic microsomes enriched the microsomes with free cholesterol and stimulated cholesterol esterification. The rate of cholesterol esterification correlated well (r = 0.96) with the concentration of microsomal free cholesterol. Lipoproteins from normal and hypercholesterolemic serum varied in their propensity to stimulate cholesterol esterification. Among the normal lipoproteins, low density lipoproteins was more stimulatory than either high density lipoproteins or intermediate density lipoproteins. However, the intermediate density lipoproteins fraction from hypercholesterolemic serum was consistently more stimulatory than any of the normal lipoproteins. The augmentation of cholesterol content, when microsomes were exposed to mixed hyperlipidemic lipoproteins, was proportionately much greater than augementation of phospholipid or protein concentration.

Animals↗
PubMed1979

Projection of the cerebellar dentate nucleus onto the frontal association cortex in monkeys.

Stimulation of the cerebellar dentate nucleus in monkeys elicited responses in the frontal association cortex (area 9) on the contralateral side to the stimulation, in addition to those in the motor (area 4) and premotor (area 6) cortices which were reported previously. The responses in the frontal association cortex were characterized by surface positive-deep negative field potentials in the cortex. They contrasted with surface negative-deep positive potentials in the motor and premotor cortices on the same dentate nucleus stimulation. In the rostral part of the premotor cortex (area 6) on the border of area 9, both types of responses were induced and admixed. The relay nucleus of the thalamus was suggested for the dentate-induced responses in the frontal association cortex.

Animals↗
PubMed1979

Influences of cerebellar hemispherectomy on slow potentials in the motor cortex preceding self-paced hand movements in the monkey.

With chronically implanted electrodes, surface negative and deep positive, slowly increasing potentials were recorded in the forelimb area of the motor cortex prior to self-paced movements of the contralateral hand in monkeys. The slow premovement potentials were markedly reduced in size after ablation of the cerebellar hemisphere on the contralateral side to the motor cortex under recording. It was suggested that the cerebellar hemisphere (neocerebellum) participates in preparing the activity of the motor cortex prior to voluntary movements.

Animals↗
PubMed1979

Slow potentials preceding self-paced hand movements in the parietal cortex of monkeys.

In our previous paper, surface negative-deep positive slow potentials were reported to appear prior to self-paced hand movements in the premotor and the forelimb motor cortices of unanesthetized, freely moving monkeys, as recorded with the elctrodes implanted chronically in the cortices. The present study revealed that similar slow potentials were recorded also in the somatosensory cortex in most cases, but infrequently and unmarkedly in area 7, never in area 19.

Animals↗
PubMed1979

The surgical management of the unusual forms of biliary atresia.

Of 50 infants undergoing laparotomy for biliary atresia during the last 9 yr at the Kobe Children's Hospital, 9 had variant forms, including (A) a gallbladder with a demonstrable connection with the intrahepatic biliary system, (B) a gallbladder with a connection with the extrahepatic biliary system and duodenum, and (C) a grossly visible subhepatic cyst. Three patients with form A underwent cholecystoduodenostomy. All these patients died of cholangitis and hepatic failure within 2 mo after operation. Two patients with form B were successfully treated by hepatic portocholecystostomy without any episodes of cholangitis. Two of the patients with form C, occurring in 1970, underwent an anastomosis between the subhepatic cyst and the duodenum. There was no bile excretion in these patients. The other two patients were treated subsequently by hepatic portoenterostomy with complete excision of the subhepatic cyst and excellent bile excretion was obtained. Infants with forms A and C should be treated by hepatic portoenterostomy instead of a direct anastomosis between the dilated portion of the extrahepatic biliary system and the alimentary tract. For patients with form B, hepatic portocholecystostomy seems to be the most suitable procedure relative to the prevention of postoperative cholangitis, which is the most serious complications in infants obtaining successful bile excretion.

Bile Ducts↗
PubMed1979

Brilliant Lake Red R as a cause of pigmented contact dermatitis.

Twenty-three patients suffering from pigmented contact dermatitis caused by cosmetics containing Brilliant Lake Red R were observed. Commercial samples of Brilliant Lake Red R proved to contain many ethyl acetate extractable impurities; 1-phenylazo-2-naphthol and azobenzene were isolated and identified. To determine the responsible allergens, five patients were examined by patch tests with purified samples of azo-dyes and the unidentified fractions of ethyl acetate extractable impurities. Three out of five showed weaker reactions to purified samples of Brilliant Lake Red R and the other two showed equal reactions compared to the commercial product. 1-Phenylazo-2-naphthol was found to be a strong allergen in all cases but none showed a positive reaction to azobenzene. Some unidentified fractions also gave positive results. Patch tests were performed with 4-phenylazo-1-naphthol, 4-phenylazo-1-naphthol-2-carboxylic acid, and 2,4-bis(phenylazo)-1-naphthol, as structurally related compounds derived from 1-naphthol. All gave negative and they were not detected in the ethyl acetate extractable impurities by thin-layer chromatography.

Adult↗
PubMed1979

Effect of dextran sulphates on thrombin activity.

To clarify the action of dextran sulphate, a heparin analogue, in the clotting of fibrinogen by thrombin, determinations were carried out on the clotting activity, the release of fibrinopeptides from fibrinogen, and the hydrolytic activity of thrombin against a peptide chromogenic substrate in the absence or presence of antithrombin III (heparin cofactor). It was shown that dextran sulphate itself inhibited thrombin activity, and its inhibition was dependent on the molecular weight and the sulphur content of the dextran sulphate. Although heparin markedly enhanced the antithrombin activity of antithrombin III, dextran sulphate did not activate antithrombin III.

Antithrombin III↗
PubMed1979

67Ga scanning in the evaluation of esophageal carcinoma.

Eighty-nine patients with histologically proved esophageal carcinoma were scanned with 67Ga to screen for extramural tumor extension and lymph-node involvement. Radiation dose and reduction of uptake were correlated. 67Ga accumulation indicated extramural extension with a sensitivity of 67% and a specificity of 93%. Marked uptake in an extraprimary site in the mediastinum or upper abdomen indicated lymph-node involvement with a sensitivity of 27% and a specificity of 100%. Irradiation with more than 20 Gy (2,000 rad) reduced uptake (P less than 0.05). 67Ga scanning appears to be useful in the evaluation of esophageal carcinoma.

Carcinoma, Squamous Cell↗