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Biomedical subjects

S Katayama

Publications and source records attributed to S Katayama.

At least 397 records · Page 22Linked to original sources
PubMed1987

Increased thromboxane B2 excretion in diabetes mellitus.

Thromboxane (TX) A2 is a potent vasoconstrictor as well as a proaggregator of platelets. Augmented TXB2 platelet synthesis and attenuated vascular prostacyclin formation have been demonstrated in diabetes mellitus. We undertook to establish a simple method of extracting urinary TXB2 (UTXB2) and to elucidate the pathophysiologic role of renal TXA2 in diabetes mellitus. One-step extraction of UTXB2 with an octadecylsilyl-silica column was sufficient as pretreatment for TXB2 radioimmunoassay because recovery of UTXB2 was good, the eluate was parallel with the dose-response curve, and the value coincided with that obtained by the conventional method. When platelet TXA2 synthesis was completely suppressed by administration of 100 mg aspirin, urinary TXB2 excretion (UTXB2V) declined to 41% of the initial levels, suggesting that renal TXA2 formation contributes significantly to UTXB2V. UTXB2V was 94.5 +/- 14.0 ng/day or 108.8 +/- 17.3 ng/gm creatinine in controls. Approximately half of the patients with diabetes demonstrated a UTXB2 level higher than the mean + 2 SD level of controls. Although UTXB2V did not show a significant correlation with protein excretion, UTXB2V in patients with diabetes with proteinuria greater than 100 mg/day was augmented (224.4 +/- 30.5 ng/day) compared with that in patients with diabetes without proteinuria greater than 100 mg/day. Furthermore, UTXB2V correlated negatively with the p-aminohippuric acid clearance rate, but not with the creatinine clearance rate. The results suggest that renal TXA2 synthesis may be augmented in diabetic nephropathy and may play a pathophysiologic role in renal hemodynamics as well as in protein excretion.

Adult↗
PubMed1986

Occurrence of Gal beta (1----3) GalNAc-Ser/Thr in the linkage region of polygalactosamine containing fungal glycoprotein from Cordyceps ophioglossoides.

The nitrous acid deamination liberated the N-acetyl galactosamine containing glycoproteins from galactosminoglycan (CO-N) which has been isolated from Cordyceps ophioglossoides culture. Mild alkaline borohydride degradation of the purified glycoprotein released oligosaccharide alditols. The smallest oligosaccharide alditol was characterized to be Gal beta (1----3)-GalNAcol. This result indicated that polygalactosamine part attached to protein part via Gal beta (1----3) GalNAc-Ser/Thr as the linkage region. To our knowledge, this is the first report of Gal-GalNAc-Ser/Thr linkage from fungal glycoprotein.

Fungal Proteins↗
PubMed1986

Intermediate lymphocytic lymphoma of the thyroid. An immunologic and immunohistologic study.

Four cases of thyroid lymphomas are presented showing curious histologic difficult to distinguish from severe lymphocytic thyroiditis by routine histologic study alone. The age of the patients ranged from 39 to 63 years. Three female patients suffered from autoimmune (lymphocytic) thyroiditis for 2 to 20 years until the present illness. A male patient had no history of thyroiditis. Rapid growth of struma in these patients suggested an evolution of malignant lymphomas. Histologic study results showed that small atypical lymphoid cells with slightly irregular and indented nuclear contour surrounded randomly distributed secondary follicles as a wide mantle. Immunohistologic staining showed that these atypical small lymphoid cells expressed surface properties intermediate between mantle-zone lymphocytes and germinal center cells with a restricted expression of kappa chain in three cases. Stages of tumors were stage I in three cases and stage II in one case. The findings demonstrated were intermediate lymphocytic lymphomas of the thyroid.

Antibodies, Monoclonal↗
PubMed1986

Radiation-associated thyrotoxicosis.

We studied 154 consecutive patients with a diagnosis of thyrotoxicosis seen at Roswell Park Memorial Institute from 1963 to 1982. The retrospective review of the clinical materials revealed that 23 (15%) had a previous history of therapeutic radiation for various diseases. The radiation dose ranged from several to 3600 rads to the thyroid with a mean latency of 14.2 +/- 3.0 years. In 11 out of 16 patients who were tested for antithyroglobulin and antimicrosomal showed positive titers of either or both antibodies (69%). In a small number of patients, thyroid stimulating immunoglobulins were studied; long-acting thyroid stimulators (LATS) were positive in one of six tested and thyrotrophin binding inhibitory immunoglobulins (TBII) in five of eight. The radiation-associated thyroidal dysfunction appears to be associated with the organ-specific autoimmune processes and could manifest as either hypo- or hyperfunction of the gland.

Acne Vulgaris↗
PubMed1986

Metastasizing atrial myxoma: a case with multiple subcutaneous tumours.

We report a case with rapidly growing subcutaneous and intra-muscular tumours that were identical histopathologically to a pre-existing left atrial myxoma. No invasion of visceral organs or skeleton was found. This is a very rare case of metastasizing myxoma with wide dissemination and rapid metastastic growth, despite the benign appearance of the original tumour.

Adult↗
PubMed1986

Plasmacytoma and follicular lymphoma in a case of Hashimoto's thyroiditis.

Monoclonal gammopathy (IgG, lambda) in a 37-year-old man with Hashimoto's thyroiditis, was markedly decreased after thyroidectomy. Histological examination of the thyroid showed large lymphoid follicles surrounded by a massive proliferation of plasma cells. Immunological studies revealed that interfollicular plasma cells stained monotypically for lambda chain, findings in keeping with a diagnosis of plasmacytoma of the thyroid. In addition, there was kappa monotypic staining of the lymphoid follicles and absence of tangible body macrophages, indicating the presence of a follicular lymphoma derived from a separate cell line from the plasmacytoma.

Adult↗
PubMed1986

Lincomycin stimulates synthesis of TEM-2 beta-lactamase by Escherichia coli.

Lincomycin increased the TEM-2 beta-lactamase activity of Escherichia coli K-12 cells carrying plasmid RP4 at a concentration which slightly inhibited cell growth. In a control culture beta-lactamase activity reached its maximal level in late log phase, whereas when lincomycin was present beta-lactamase activity continued to increase into the stationary phase. Lincomycin (100 micrograms/ml) inhibited both cell growth and protein synthesis by about 35% but stimulated beta-lactamase activity 2.5-fold per ml of culture and about 4-fold per cell after 20 h of growth. The amount of beta-lactamase produced in each culture was also compared by densitophotometry of a stained sodium dodecyl sulfate-polyacrylamide gel. The relative values were in good agreement with the relative enzyme activities, indicating that the stimulatory effect of lincomycin was due to an increase in the amount of beta-lactamase protein. Inactivation of beta-lactamase appeared to be faster when lincomycin was present. This was determined by measuring the decrease in beta-lactamase activity when phenethyl alcohol was present to prevent maturation of the enzyme. There was no significant difference in plasmid copy number between the cells grown in the presence or absence of lincomycin. These results indicate that lincomycin stimulates transcription, translation, or translocation of beta-lactamase.

Electrophoresis, Polyacrylamide Gel↗
PubMed1986

[General pharmacological action of tritoqualine (TRQ; (+/-)-(R*)-7-amino-4, 5, 6-triethoxy-3-[(R*)-5, 6, 7, 8-tetrahydro-4-methoxy-6-methyl-1, 3-dioxolo [4, 5-g] isoquinolin-5-yl] phthalide].

The general pharmacological action of TRQ was investigated, and the following results were obtained: With regard to its influence on the central nervous system, TRQ moderately potentiated the actions of hexobarbital (sleeping time) and methamphetamine (stereotyped behavior) at doses above 100 mg/kg, p.o. TRQ, however, had little influence on behavioral changes, EEG and motor function. TRQ only had slight influence on the respiratory and cardiovascular system at doses ranging from 0.1 to 3 mg/kg, i.v. Significant decrease in SBP and increases of HR, FAF and respiratory rate were observed after high doses (10-30 mg/kg, i.v.) of TRQ. TRQ also had little influence on contractility and pacemaker in isolated hearts, but moderately increased the coronary flow. The inhibitory effect of TRQ on the isolated smooth muscle was observed at high concentration and was non-specific. Furthermore, TRQ exhibited little influence on the autonomic nervous system. Among the effects of TRQ on the gastrointestinal system, it was shown that TRQ moderately increased the outflow of bile after doses above 1 mg/kg, i.v. TRQ also showed no remarkable actions on other aspects of the gastrointestinal system and blood coagulation system. Considering the present results, it may be suggested that there should be no serious problems in the application of TRQ as a hepatoprotective agent.

Animals↗
PubMed1986

Spontaneous autoimmune thyroiditis in Bio Breeding/Worcester (BB/W) rat.

We investigated the serial changes in the plasma levels of anti-thyroglobulin antibody (ATA) by solid-phase enzyme immunoassay, thyroid hormones and blood glucose, since spontaneous occurring lymphocytic thyroiditis (LT) has been found in spontaneously diabetic Bio Breeding/Worcester (BB/W) rat. We also observed the correlation between these levels and histological findings in the thyroid gland. The incidence of diabetes was 0% in 5 week old rats (group A), 70% in 11 week old rats (group B), and 86% in 20 week old rats (group C), while LT was observed in 0% in group A, 20% in group B and 48% in group C. Although the incidence of both increased with age, there was no link between LT and diabetes. Plasma ATA levels were 91.4 +/- 28.5 (OD492 X 1,000, mean +/- SEM) in the control (14 week old Wistar Furth) rats. 49.5 +/- 15.4 in group A, 197.8 +/- 41.5 in group B, and 376.7 +/- 48.7 in group C, again showing a clear increase with age. In group C, the plasma levels of ATA in rats with LT were significantly higher than those without LT. In addition, 6 out of 11 rats without LT had abnormaly high ATA levels. In group C, the plasma levels of free 3,5,3'-triiodothyronine (FT3) and total thyroxine (TT4), and also the FT3/TT4 ratio were significantly lower and the plasma levels of blood glucose were higher than in the other groups. There was no difference between the plasma thyroid hormone levels in rats with LT and those without LT. These studies suggest that LT may occur independently of insulitis, namely diabetes, ATA levels and the incidence of LT increase with age, the site of ATA production may not be confined to the thyroid gland, and the derangement of glucose metabolism may be one of the factors in the decrease in plasma thyroid hormone. The BB/W rat is not only a useful animal model to use in exploring the pathogenesis of human insulin-dependent diabetes mellitus, but also spontaneous autoimmune thyroiditis.

Age Factors↗
PubMed1986

Comparative study of various H1-blockers on neuropharmacological and behavioral effects including 1-(2-ethoxyethyl)-2-(4-methyl-1-homopiperazinyl)benzimidazole difumarate (KB-2413), a new antiallergic agent.

In a conditioned avoidance response tested in rats, all of the H1-blockers employed caused a dose-related inhibition at doses 5-20 mg/kg (i.v.) except for ketotifen that elicited significant suppression even at a dose of 1 mg/kg. No inhibition was seen after administration of 1-(2-ethoxyethyl)-2-(4-methyl-1-homopiperazinyl)benzimidazole difumarate (KB-2413). ED50s were ranged from 4.1 to 7.4 mg/kg in diphenhydramine, pyrilamine and promethazine. In laminectomized rats, diphenhydramine, pyrilamine, promethazine and ketotifen suppressed the amplitudes of monosynaptic reflex potentials at doses higher than 2 mg/kg (i.v.). In the case of chlorpheniramine, significant inhibition was observed at a dose of 20 mg/kg. In a polysynaptic reflex, similar but less prominent inhibitions were affected by those drugs. However, KB-2413 did not influence spinal reflexes even at a dose of 20 mg/kg. In the rat phrenic nerve-diaphragm preparation, perfusion of H1-blockers at a concentration of 10(-5) M decreased the amplitudes of end-plate potentials except for chlorpheniramine and KB-2413. At 10(-4) M, all the test drugs caused significant inhibition. When the action potential of superior cervical ganglion was measured by the sucrose gap method, promethazine inhibited the action potential significantly at 10(-6) M, but the rest of the test drugs depressed the potentials at 10(-5) M. In spontaneous EEG, all H1-blockers caused a marked drowsy pattern at lower doses (2-5 mg/kg) except for chlorpheniramine, while in higher doses (10-20 mg/kg) epileptic signs in EEG with or without convulsive behavior were noticed. However, after KB-2413 (5-20 mg/kg) neither drowsy nor seizure pattern was observed, in EEG or behavior.

Action Potentials↗
PubMed1986

[Operated case of cerebral venous angioma with early venous filling on cerebral angiography--case report].

A 34-year-old woman had a generalized convulsion of sudden onset on April 30, 1985. The next day, she suffered a reattack of generalized convulsion. She was admitted to Kokura Memorial Hospital on May 13, 1985, and was found to have intracerebral hemorrhage on CT-scan then, underwent surgical procedure. Based on cerebral angiographic findings and histological examination, the diagnosis of cerebral venous angioma was done. Cerebral venous angioma is a relatively rare vascular malformation. Its characteristic angiographic findings are a normal arterial phase and a local network of small vein that converged centrally into a single large vein. However, this present case of venous angioma in the left frontal lobe with hematoma showed not only characteristically enlarged medurally vein, but also early venous filling. The literature of operated venous angioma with early venous filling of the brain are reviewed and discussed.

Adult↗
PubMed1985

Morphological and biochemical studies on minocycline-induced black thyroid in rats.

The thyroid glands of the rats treated with 100 mg/kg/day of minocycline for 35 days showed black discoloration. In these thyroids, brown pigment granules were seen in the follicle epithelial cells, and they histochemically stained in the same manner as melanin. By electron microscopy, the deposition of the electron-dense material first occurred in lysosome-like granules and, with further administration, was observed also in the rough endoplasmic reticulum in some cells. Thin-layer chromatography showed that the Rf value of the extract from minocycline-treated rat thyroid was the same as that of the black substance obtained by mixing minocycline and 3% hydrogen peroxide but different from that of melanin. In minocycline-treated rats, the release of thyroxine (T4) from perifused thyroids was significantly less than that from control, and the analysis of iodoamino acids showed an increased monoiodotyrosine fraction. Thus, the pigment of thyroid in minocycline-treated rats was demonstrated to be a metabolic derivative of minocycline itself and minocycline may interfere with thyroid function in high-dose, long-term treatment.

Administration, Oral↗