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Biomedical subjects

Y Ohta

Publications and source records attributed to Y Ohta.

At least 973 records · Page 54Linked to original sources
PubMed1985

Paradoxical antagonism of neuromuscular block by vecuronium metabolites.

Vecuronium is hydrolyzed in the body to 3-deacetyl (ORG 7268), 17-deacetyl (ORG NC58), and 3, 17-bis-deacetyl (ORG 7402) derivatives. Interactions of vecuronium and these metabolites were studied in phrenic nerve-hemidiaphragm preparations of rats. As already reported, ORG 7268 had a potent neuromuscular blocking action, and ORG NC58 and ORG 7402 had a weak neuromuscular blocking action. As expected, ORG 7268 increased the degree of neuromuscular block by vecuronium. However, a low concentration (10 microM) of ORG NC58 and ORG 7402 reversed the block by vecuronium. At a high concentration (50 microM), ORG NC58 and ORG 7402 increased the degree of block by vecuronium. Although we do not have enough data to explain these paradoxical reversal of neuromuscular block at this moment, we postulate that these results reflect the interaction between "slow" and "fast" competitive antagonists. Regardless of the mechanism, it should be emphasized that the concentrations of ORG NC58 and ORG 7402 which are necessary to reverse the block are much lower than those which facilitate the block. It is conceivable that this paradoxical reversal of the block occurs in experimental and clinical situations. Therefore, in determining the neuromuscular blocking action of a compound, the "antagonistic" effect of its metabolites should also be considered.

Animals↗
PubMed1985

[Study on toxicity of halopredone acetate. (III). Chronic toxicity study in rats].

Chronic toxicity study of halopredone acetate (THS-201), a synthetic corticosteroid, was carried out using Jcl: Wistar rats. THS-201 was subcutaneously administered to the rat in doses of 0.02, 0.1, 0.5 and 2.5 mg/kg/day, with the periods for administration and recovery being 12 and 2 months, respectively. In the group of THS-201 2.5 mg/kg, the below findings were observed: thinning of lumbar hair, suppression in body weight gain, decrease of food consumption in both sexes and decrease of water consumption in male. The lesions to lymphatic system were indicated by the examinations of hemogram, organ weight and histopathology. A few changes in urinary and biochemical values were seen, and foreign body granuloma was observed in the injected subcutis. After 2 month-recovery period, above-mentioned findings almost disappeared. In the group of THS-201 0.5 mg/kg, some of the changes were noted slightly and disappeared after the recovery period. In the groups of THS-201 0.1 and 0.02 mg/kg, any toxic changes attributable to THS-201 were not observed. It was concluded that the non-toxic dose and the defined toxic dose of THS-201 in this study were 0.1 and 0.5 mg/kg/day, respectively.

Animals↗
PubMed1985

Hemoglobin A2 Honai (alpha 2 delta 2(90)(F6)Glu----Val): a new delta chain variant.

A new slow-moving variant of hemoglobin(Hb) A2, designated as Hb A2 Honai, was found to have an amino acid substitution of valine for glutamic acid at position 90(F6) in the delta chain. Hb A2 Honai comprised 0.84% of total hemoglobin. Hb A2 and Hb A were estimated to be 1.30% and 97.85%, respectively. Hb A2 Honai was observed in 4 members of a family in 3 generations. No hematologic abnormalities were associated with Hb A2 Honai.

Aged↗
PubMed1985

Increased asialo-alpha-fetoprotein in patients with alpha-fetoprotein-producing tumors: demonstration by affinity electrophoresis with erythroagglutinating phytohemagglutinin of Phaseolus vulgaris lectin.

Affinity electrophoresis of human alpha-fetoprotein (AFP) with the erythroagglutinating phytohemagglutinin of Phaseolus vulgaris (E-PHA) gave up to five resolved bands (y, h, i, l and a; given in the order of decreasing affinity for E-PHA); band a having no affinity and bands y and h representing asialo-AFP's. The proportion of band y increased in extrahepatic tumors producing AFP, including yolk sac tumor, and of band h, in addition, in hepatocellular carcinoma. The proportion of either band y or h (or y + h) increased, over the means plus 2 standard deviations of the respective bands of cord serum AFP, in 20 out of 25 cases (80%) of hepatocellular carcinoma, including cell lines, and in all the patients with extrahepatic malignancy. Band i was detected in more than half the cases with malignancy, although the extent of its increases was much less. Band a appeared only in limited cases. None of the hepatitis and cirrhotic patients showed increased proportions of band y or h (or y + h), indicating the usefulness of the determination of asialo-AFP for the discrimination between benign and malignant liver diseases.

Adenocarcinoma↗
PubMed1985

Hepatic triglyceride lipase and lipoprotein lipase activities in post-heparin plasma of patients with various cancers.

The total post-heparin lipolytic activity (PHLA) and hepatic triglyceride lipase (HTGL) and lipoprotein lipase (LPL) activities in post-heparin plasma of patients with various cancers were measured. In patients with cancers, PHLA was similar to that of controls, but the HTGL activity was decreased and the LPL activity was increased. Thus, in cancer patients the ratios of HTGL to PHLA were lower, and the ratios of LPL to PHLA were higher than in controls. No correlation was found between the plasma lipid level and HTGL or LPL activity.

Aged↗
PubMed1985

11;14 translocation in childhood T-cell acute lymphoblastic leukemia.

No consistent chromosome abnormalities have been reported so far in T-cell lymphoma-leukemia. We report here two children suffering from T-cell acute lymphoblastic leukemia (ALL) with t(11;14)(q13;p11). Even though the breakpoints we claim are different from those in a recent report, we believe that their cases and ours have the same abnormality and that patients with this abnormality constitute a distinct subgroup of T-cell ALL positive for sheep erythrocyte receptor (E+) in children.

Child↗
PubMed1985

[Suture material in vaginal hysterectomy].

In order to find the best suture material to use for vaginal hysterectomies, we examined the tensile strength, stretchability and contractibilty of suture materials such as silk, chromic and plain catgut, and dexon under both wet and dry conditions. We also observed the incidence of postoperative hemorrhage, granulation and healing of the vaginal stump. Under dry conditions, the tensile strength, stretchability and contractibility was greatest in No. 3 plain catgut. (plain catgut greater than chromic catgut greater than dexon or silk) Under wet conditions, the tensile strength was not so changed, but the stretchability of catgut and silk was increased and that of dexon was low and unchanged. The contractibility of all types of suture material was increased. Silk had low tensile strength, was not absorbable and became an infectious foreign body. Dexon had low stretchability and tended to result in postoperative hemorrhage. Chromic catgut was frequently found to cause infectious granulation and postoperative hemorrhage in the vaginal stump. Plain catgut was easily absorbed and had the greatest tensile strength and stretchability. Plain catgut was considered to be the most suitable suture material for vaginal hysterectomy.

Biomechanical Phenomena↗