PubMed Health⌕ Search

Biomedical subjects

M Kasuya

Publications and source records attributed to M Kasuya.

At least 55 records · Page 3Linked to original sources

DIDS, an anion transport blocker, modulates ivermectin-induced enhancement of benzodiazepine receptor binding in rat brain.

Ivermectin enhancement of [3H]diazepam binding was abolished by pretreatment of membranes with 0.05% Triton X-100, whereas GABA-induced enhancement was not changed after this treatment. Ivermectin enhancement was neither affected by picrotoxinin nor dependent on the chloride ion. 4,4'-Diisothiocyano-2,2'-disulfonic acid stilbene (DIDS) dose-dependently reduced [3H]diazepam binding enhanced by 10(-6) M ivermectin, without affecting the basal specific binding. The effects of DIDS were derived from reduction of increased binding affinity of benzodiazepine receptors by ivermectin, but were not dependent on chloride ion in the assay medium. DIDS inhibited GABA- and pentobarbital- but not chloride ion-induced enhancement of [3H]diazepam binding.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

Urinary trehalase activity and renal brush-border damage in inhabitants of a cadmium-polluted area (Jinzu River basin).

Elevated urinary trehalase activity was observed in the inhabitants of the Jinzu River basin. Urinary trehalase activity was correlated with other urinalysis components, such as beta 2-microglobulin, glucose, amino nitrogen, and cadmium, of which a high level was observed in cadmium-polluted areas as compared with the reference area. Renal trehalase is specifically localized in tubular brush borders [M. Nakano, J. Histochem. Cytochem., 30 (1982) 1243-1248]. From these results it is inferred that tubular brush-border damage occurs in inhabitants of the Jinzu River basin.

Aged↗

The changing prevalence of respiratory symptoms in atopic children in response to air pollution.

Following the promotion of anti-air pollution measures in steam power stations using crude oil, atmospheric concentrations of sulphur dioxide, nitrogen dioxide and suspended particulates have declined. These changes in atmospheric concentrations were accompanied by a decline in the prevalence of respiratory symptoms among schoolchildren living near the power stations. In analysing the correlation between air pollutant concentrations and the prevalence of respiratory symptoms, those with positive skin reactions to house dust extract (the positive group) showed a more significant correlation coefficient compared to those who had never had a positive skin reaction (the negative group). In addition, schoolchildren more heavily exposed to air pollutants showed the higher prevalence of respiratory symptoms than the others. With regard to the kind of air pollutants, both sulphur dioxide and nitrogen dioxide were more closely associated with the prevalence of respiratory symptoms than suspended particulates. This study has therefore demonstrated that the positive group is a useful population for monitoring the health effects associated with low-degree air pollution of gaseous agents.

Adolescent↗

Effect of cadmium chloride and Cd-metallothionein on the nervous tissue culture.

Influence of metallothionein (MT) isolated from rat liver on rat cerebellum in culture was investigated by comparison with that of CdCl2. Cd-MT at 0.2 X 10(-5) M as Cd significantly depressed the outgrowth of nerve fibers, fibroblasts and glial cells as compared to the control culture. In the range from 0.2 X 10(-5) M to 2.7 X 10(-5) M Cd, the toxicity of Cd-MT was the same as that of CdCl2. Above 5 X 10(-5) M Cd, however, the toxicity of Cd-MT was less than that of CdCl2. Cadmium added as CdCl2 was perfectly recovered at a region of higher Mr than MT on the Sephadex G-75 column. Cadmium added as Cd-MT was detected in part at the higher Mr region and in part at the MT region, depending on incubation time and Cd concentration in the medium. The toxic action of Cd-MT was proportional to the recovery level of Cd at the higher Mr region.

Animals↗

Demonstration of vitamin D-binding protein (Gc-globulin) in the urine of Itai-itai disease patients.

Vitamin D-binding protein (VDBP, known as Gc-globulin) was discovered by an immunochemical method in the urine of patients with Itai-itai disease. The urine and sera of Itai-itai disease patients produced specific precipitin lines with anti-human VDBP antisera. The electrophoretic mobility of the protein in the urine is the same as that in the serum. A significant correlation was found between VDBP and beta 2-microglobulin in the urine. Based on this result, it was concluded that Itai-itai disease is associated with disturbances of vitamin D transport and/or metabolism.

Aged↗

The effect of methylcobalamin on the toxicity of methylmercury and mercuric chloride on nervous tissue in culture.

Methylcobalamin (methyl-B12, vitamin B12 analog) at a concentration of 0.2 x 10(-5) M tended to inhibit the toxic effect of 1 and 1.5 x 10(-5) M methylmercuric chloride (MMC) on the development of nerve fibers, glial cells and fibroblasts from newborn rat cerebellum explants. Methyl-B12 at greater than 1 x 10(-5) M significantly inhibited the toxic effect of 1 and 1.5 x 10(-5) M MMC. However, the protective effect of methyl-B12 against the toxicity of mercuric chloride (MC) was not significant. These results are in accord with an interaction of alkyl mercurials with membranes of nervous tissue, producing the degenerative changes in the cells, since vitamin B12 increases the lipid synthesis in nervous tissue. The results also indicate that the mechanism of toxic action of organic mercury is different from that of inorganic mercury.

Animals↗

The effects of phthalate esters on fibroblasts in primary culture.

The toxicity of butylbenzyl phthalate(BLP), di-n-heptyl phthalate (DNHP) and n-butyl lauryl phthalate (BLP) to fibroblasts from newborn rat cerebellum in primary culture was significant at concentrations of 7.0, 2.7, and 5.0 x 10(-4) M, respectively. The toxicity of di-methoxyethyl phthalate(DMEP), butyl phthalyl butyl glycolate(BPBG), di-n-octyl phthalate(DNOP), and di-(2-ethylhexyl) phthalate(DEHP) was not significant. Phthalic acid and potassium hydrogen phthalate (K-phthalate) were the least toxic to fibroblasts. Comparison of the toxicity to fibroblasts of five phthalate esters of normal series showed that dimethyl phthalate(DMP) < diethyl phthalate(DEP) < di-n-butyl phthalate(DNBP) > DNHP > DNOP.

Animals↗

Toxicity of butylbenzyl phthalate (BBP) and other phthalate esters to nervous tissue in culture.

Butylbenzyl phthalate (BBP) and n-butyl lauryl phthalate (BLP) markedly inhibited the outgrowth of nerve fibers and glial cells from cerebellar explants of newborn rat in primary culture at concentrations of 7.0 and 12.5 x 10(-4) M, respectively. The toxicity of butyl phthalyl butyl glycolate (BPBG) was not significant. From these results the order of toxicity of these three phthalate esters was determined as BBP > BLP > BPBG.

Animals↗

Interactions between mercuric chloride and sodium selenite on cultured rat cerebrum.

Explants of rat cerebrum in culture were treated with toxic concentration of HgCl2 of 1 x 10(-4) M and with varying concentrations of sodium selenite. Treatment with sodium selenite resulted in a reduced neurotoxicity of HgCl2, a maximal effect being attained at a selenite concentration of 1 x 10(-5) M. However, 1 x 10(-5) M sodium selenite was itself toxic. In in vitro cell systems, the toxicity of either mercury or selenium is decreased in the presence of the other element.

Animals↗