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T Harada

Publications and source records attributed to T Harada.

At least 901 records · Page 50Linked to original sources
PubMed1987

[Measurements of monoamine neurotransmitter metabolism by in vivo voltammetry].

In vivo voltammetry is an electrical detection method by which dopamine and serotonin metabolism can be estimated in the brain of animals. In the present report preliminary and basic experiment were performed before its application to ischemic brain. Firstly, using voltammetry DPV-5 system in vitro, concentration/amplitude curve was obtained with various concentration of 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) diluted in phosphate buffer (pH 7.4). DOPAC appeared at +150 mV (peak 2) while 5-HIAA appeared at +300 mV (peak 3). A linear relation was obtained in the concentrations ranging 5 x 10(-6)-10(-4) M for DOPAC and 10(-6)-10(-4) M for 5-HIAA. While a delay in oxidation potential was noticed for both peaks 2 and 3 by about 30 mV when the pH of solution was decreased by 1. Secondly the DPV-5 system was applied in vivo to the rat striatum. Peak 2 was observed at +150 mV which was increased by intraperitoneal injection of haloperidol, a dopamine receptor blocker and decreased by pargyline, a monoamine oxidase inhibitor. While peak 3 was observed at +300 mV and increased after probenecid and decreased by pargyline, which suggest that peak 2 and 3 correspond to DOPAC and 5-HIAA respectively. Thirdly DPV-5 system was applied to the rat striatum and rat's heart was arrested by KCl injection as a model of extreme brain ischemia. Shortly after cardiac arrest the heights of peak 2 was significantly increased to 600-900% while the increase of peak 3 was not significant, both of which subsided gradually toward 30 minutes after arrest.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗
PubMed1987

Papillary carcinoma of the thyroid. A histochemical, immunohistochemical and ultrastructural study with special reference to the follicular variant.

Twenty-one papillary thyroid carcinomas (PTCs), grouped into predominantly papillary (14 cases), predominantly follicular (5 cases), and extremely follicular, i.e., follicular variant (2 cases) types, were studied in comparison with three cases each of follicular lesions including follicular carcinoma, follicular adenoma, adenomatous goiter and Graves' disease. Histochemical, immunoperoxidase, and electron microscopic analyses demonstrated no remarkable differences between the predominantly papillary and predominantly follicular PTCs, but the presence of common characteristics distinct from those of the follicular lesions. These two types of PTCs showed less glycogen, more mucoid material, more epidermal keratin, less thyroid hormone with relative predominance of T3 over T4, and more interdigitating reticulum cells (IDCs) than most of the follicular lesions. Ultrastructurally, the tumor cells of these PTCs had markedly irregular nuclei, a vesicular chromatin pattern, and small basally located lysosomes, in contrast with the cells in the follicular lesions which had smooth round nuclei, more heterochromatin, and apical or dispersed lysosomes of various sizes. The follicular variant PTCs showed some mixed features, such as glycogen in the follicular portion and mucoid material in metastatic papillary foci, positive keratin and IDCs but greater amounts of thyroid hormone, and a rather intermediate type of ultrastructure with only mildly irregular but vesicular nuclei and large apical as well as small basal lysosomes. These findings cytologically support the WHO definition of papillary carcinoma that includes tumors with variable mixtures of papillary and follicular patterns. However, separate consideration may be necessary with regard to the follicular variant.

Adenocarcinoma↗
PubMed1987

[T-lymphocyte subsets in 20 cases of uveitis of various type].

Lymphocyte T subsets are determined by system OKT in 20 patients with various types of uveitis (Behçet disease 8, Vogt-Koyanagi-Harada disease 5, anterior uveitis 4, Kirisawa type uveitis 1, uveitis associated with Psoriasis vulgaris 1, undetermined type uveitis 1). Augmentation of OKT 8+ (p less than 0.05) associated with reduction of OKT 4+/OKT 8+ was found as compared with normal individuals. Diminution of OKT 4+/OKT 8+ (p less than 0.05) was noted in 5 patients with Behçet disease in association with augmentation of OKT 8+ (p less than 0.005). In Vogt-Koyanagi-Harada disease there is augmentation of OKT 8+ (p less than 0.05) which is, however, not so marked as in Behçet disease. On the contrary anterior uveitis was characterized by a remarkable rise in OKT 4+/OKT 8+.

Antibodies, Monoclonal↗
PubMed1987

Cadmium-induced osteopathy: clinical and autopsy findings of four patients.

Clinical and autopsy findings of 4 patients with chronic cadmium toxication by peroral uptake of cadmium are reported. Cadmium toxication was liable to occur in multiparous postmenopausal women, and it began with proteinuria, glycosuria, lumbago and bone pain. Then, renal function gradually decreased being accompanied with renal tubulopathy. Autopsy disclosed renal tubulopathy, which consisted of the flattening of the epithelium of proximal convoluted tubules at the peripheral portion and the mild thickening of the tubular basement membrane. There was no primary change in the glomerulus and renal interstitium. Osteomalacia was observed in the vertebrae and several other bones. The degree of osteomalacia was in good agreement with chronic renal tubular dysfunction. A decrease of the estrogen content, in addition to renal tubulopathy due to biological saturation of cadmium, seems to play an important role in the pathogenesis of cadmium-induced osteomalacia.

Acidosis, Renal Tubular↗
PubMed1987

Long-term prognosis and prognostic indices of IgA nephropathy in juvenile and in adult Japanese.

For a comparative study of IgA nephropathy occurring in Japanese adolescents and adults, the clinical and histological findings and prognosis (follow-up period; 12 +/- 6 years for children and 10 +/- 5 years for adults) were compared. The subjects studied included 98 children and 86 adults. Development into renal failure occurred in 9 children (9.2%) and in 20 adults (23.3%), (p less than 0.01). The actuarial renal survival rate at year 10 after the onset of glomerulonephritis in children and adults was 95% and 80%, respectively, and at year 20, 82% and 50%, respectively. The prognosis was definitely better in the children and this was attributable to the observation that (1) the glomerular injury at the initial biopsy in children was less extensive than in adults; (2) the frequency of complication with hypertension was lower in children (27.6%) than in adults (41.9%), (p less than 0.05); (3) hypertension was one prognostic indice, even in children, after age 30; (4) after age 40, aging and arteriosclerosis were more contributory than hypertension to the progress of IgA nephropathy; and (5) the quantity of intraglomerular immune deposits and the period of deposition were not related of prognostic indices. Thus, in the long-term prognosis of IgA nephropathy in both children and adults, immunological disorders seem to have little influence while factors such as hypertension, arteriosclerosis and aging play important roles.

Adolescent↗