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T Sakurada

Publications and source records attributed to T Sakurada.

At least 343 records · Page 19Linked to original sources
PubMed1977

Simple micro-assay methods for enzymes of purine metabolism.

Xanthine oxidase, guanase, 5'-nucleotidase, and adenosine deaminase in human epidermis were demonstrated and accurately assayed with about 20 microng. of tissue by the new micro-assay methods which rely on the isolation of isotopically labeled end products from the substrates by electrophoresis on cellulose acetate membranes. These assay methods are rapid, reliable, and sensitive and are highly suitable for studies of small amount of human tissue. Theses methods for the separation of purine derivatives with cellulose acetate membrane will also permit the assays of purine nucleoside phosphorylase and nucleoside kinase.

Acetates↗
PubMed1976

Purification and properties of cholesterol ester hydrolase from human aortic intima and media.

1. Cholesterol ester hydrolase of human aortic intima and media was isolated and purified about 650-fold with 10-15% recovery of the original activity by sequential precipitation with 35% acetone, gel filtration on Sephadex G-75 and DEAE-cellulose column chromatography. 2. Two pH optima of 4.5-5.0 and 7.0-7.5 were consistently observed for the partially purified cholesterol ester hydrolase of human aortic intima and media. 3. In the system used in the present study, the increasing concentration of emulsifiers, sodium taurocholate and phosphatidylcholine, inhibited the activity of the neutral enzymes but not on the acid enzymes. On the contrary, reaction products, cholesterol and oleic acid, were much more inhibitory on the acid enzymes than on the neutral ones. 4. Results of studies on the effect of presentation of substrate on the enzyme activity and on the difference between acid and neutral enzymes are also discussed.

Adult↗
PubMed1976

Increased peroxidase activity in Pendred's syndrome with hypothyroidism.

An 8-year-old boy with goiter and bilateral nerve deafness had a 46% discharge of radioiodine after thiocyanate administration. He was clinically euthyroid. Although the serum total T4 was low (2.4 mug/100 ml) and TSH was significantly high (181 muU/ml), the serum total T3 was normal (152 ng/100ml). It was considered that the increased release of TSH by the feedback mechanism in response to the low T4 resulted in a quite normal level of serum T3. The thyroid gland demonstrated a low stable iodine content, an increase in MIT/DIT ration and a decrease in iodothyronine. The thyroglobulin behaved normally in Sephadex G-200 chromatography and immunoreaction. Thyroid tissue exhibited increased peroxidase activity as measured by I3 formation. Increased peroxidase activity may be related to the observed increase in serum level of TSH.

Child↗
PubMed1976

Radioimmunoassay for serum thyroxine.

A new procedure for radioimmunoassay (RIA) was applied to determine the serum concentration of thyroxine (T4). Mixtures of T4-methylester hydrochloride-bovine serum albumin complex and complete Freund's adjuvant were injected to rabbits to get them immunized. Specific anti-T4 rabbit serum, high in titer, could be obtained 18 months after the start of immunization. RIA for T4 extracted by ethanol from serum was performed by an application of dextran-coated charcoal to separate bound and free 125-i-t4. on the other hand, RIA for T4 performed directly in the serum containing 100 mg/100 ml of 8-anilino-1-naphthalene-sulfonic acid (ANS) gave a similar standard curve for T4 obtained by the ethanol-extraction method. Serum T4 values obtained by the methanol-extraction method were 9.7 +/- 3.3 mug/100 ml for patients with hyperthyroidism and 0.6 +/- 0.3 mug/100 ml for those with hypothyroidism. The corresponding figures obtained by RIA in the serum containing ANS were 11.1 +/- 2.1, 19.1 +/- 3.3 and 0.7 +/- 0.7 mug/100 ml, respectively. The figures positively correlated respectively to the serum T4 values obtained by the competitive protein-binding analysis method (Tetrasrob-125).

Humans↗
PubMed1976

Increase in alkaline phosphatase activity in the liver of mice bearing Ehrlich ascites tumor.

In mice bearing Ehrilich ascites tumors, alkaline phosphatase activity was increased fivefold in the liver and by 50% in the kidney. In mice bearing solid tumors caused by inoculation of tumor cells into the axillary region, the activity of this enzyme in the liver was increased 11-fold, whereas the activity in the kidney did not change. Alkaline phosphatase activities in the liver and kidney were not altered by administration of adrenal steroids. Adrenalectomy, fasting, and pregnancy did not affect the activity of alkaline phosphatase in the liver and kidney. Treatment with tumor extracts or ascites fluid of normal mice increased liver alkaline phosphatase activity. These findings suggested that the elevation of liver alkaline phosphatase activity was cuased primarily by the tumor itself, and not by hormonal imbalance provoked secondarily by the presence of the tumor.

Adrenal Glands↗
PubMed1975

[Effect of MMI on the serum T3 and T4 levels in hyperthyroid patients (author's transl)].

Effect of 1-methyl-2-mercaptoimidazole (MMI) on the serum triiodothyronine (T3) and thyroxine (T4) was studied in six patients with hyperthyroidism. From 30 to 60 mg of MMI per day were administered to the patients orally. Serum T3 was measured by radioimmunoassay and T4 by radioimmunoassay of Tetrasorb Kit (Abbott Lab.). Serum T4/T3 ratios in these patients were low initially, but increased to normal range in two cases immediately after the administration of MMI. But they were unchanged at first in the other four cases. When high serum T3 values decreased abruptly to normal at a later course of medication, the serum T4/T3 ratios increased to normal range in almost all cases. Even though the serum T4/T3 ratio became normal, serum T3 and T4 values remained high in some cases. Elevated serum T4 values in all cases decreased to normal faster than serum T3 with the administration of MMI. When MMI was administered to the patents concinuously, the T4/T3 ratios, once increased to normal, then decreased again gradually in five cases. And serum T3 which decreased to normal sometimes gave high values. After the discontinuation of MMI, serum T3 increased over the normal range more rapidly than did T4.

Adult↗
PubMed1975

Effects of polyamines on the central nervous system.

Effects of polyamines on the central nervous system were studied in mice. Intraperitoneal administration of Spermidine (SPD) and Spermine (SPM) decreased spontaneous motor activity as measured by either the photo-cell counters method or the open-field test and lowered rectal temperature. A significant prolongation of sleeping time after pentobarbital was confirmed in small doses of SPD and SPM which had slight influence on spontaneous motor activity. The time to convulsion and death induced by strychnine was elongated by SPD and SPM. SPM in small doses inhibited writhing responses induced by 0.7% acetic acid. In addition, methamphetamine-induced hyperactivity and conditioned avoidance response were blocked by SPM in doses which decreased spontaneous motor activity. In all experiments, SPM appeared to have a powerful pharmacological activity compared with SPD. LD50 for SPD and SPM was 620 (500-769) mg/kg i.p. and 310 (200-480) mg/kg i.p., respectively.

Animals↗
PubMed1975

Exophthalmus-myxoedema circumscriptum praetibiale-osteoarthropathia hypertrophicans (E.M.O.) syndrome in Graves' disease: a review of eight cases reported in Japan.

Case 1 showed recurrence of hyperthyroidism accompanied by pretibial myxedema and digital clubbing 14 years after thyroidectomy for Graves' disease. Case 2 had had pretibial myxedema for the past 20 years and myxedema tuberosum at the right shoulder for the past 10 years, and on admission showed exophthalmos and digital clubbing with thyroid gland demonstrating histological picture of chronic thyroiditis. This case was in slight hypothyroidism and serum LATS was highly positive. Eight cases of E.M.O. syndrome have so far been reported in Japan, including our own. Six cases of these were males. Two cases did not show any sign of hyperthyroidism throughout their entire courses, including our Case 2 described here. Three cases had never received treatment for Graves' disease prior to the occurrence of this syndrome. The serum LATS was positive in all 5 cases thus far reported.

Biopsy↗