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Biomedical subjects

S Shima

Publications and source records attributed to S Shima.

At least 109 records · Page 6Linked to original sources
PubMed1987

Selective enlargement of the third ventricle found in chronic schizophrenia.

Selective enlargement of the third ventricle was observed when the area and the VBR (ventricle-brain ratio) were measured in 37 chronic schizophrenics (DSM-III criteria) as compared with 37 controls. However, the width or the width to IS (maximum inner skull width) ratio was not significantly different between the two groups. There was no correlation between any measure of the third ventricle and any of the clinical variables. Five patients had VBRs of the third ventricle that were larger than the mean + 2 SD of the control, but there was no significant difference between these five schizophrenics and the others in any of the clinical variables.

Adult↗
PubMed1987

Effect of thiamine on the excretion of subcutaneously injected lead in rats.

The effect of thiamine on the excretion of lead in feces was investigated using rats injected subcutaneously with lead acetate and thiamine pyrophosphate. The amount of lead excreted increased with the amounts of thiamine administered, while lead concentrations in blood, liver and femur also increased. The amount of lead excreted in feces decreased, however, with administration of oxythiamine and vanadium. These results suggest that excretion of lead in feces is enhanced by thiamine and that it promotes evacuation of lead from the body.

Animals↗
PubMed1987

Effect of food intake on blood lead concentration in workers occupationally exposed to lead.

Results from a cross-sectional study showed the concentration of lead in the blood of male workers, aged 20-55 years, occupationally exposed to lead in a steel factory, to be negatively correlated with the daily nutritional content of dietary fiber, iron and vitamin B1 (thiamine) intake. Furthermore, in experiments with rats injected subcutaneously with lead acetate, lead levels in blood and femur of animals on a vitamin-rich laboratory chow were lower than those fed a general laboratory chow. Moreover, in the group fed the vitamin-rich chow, lead excretion in feces increased, while excretion in urine did not. These results suggest that lead excretion from the body may be increased by a high intake of nutrients such as thiamine, iron and fiber, that lead excretion in feces via bile may be enhanced by a large intake of vitamins such as thiamine and that accordingly the lead concentration in the blood of the workers is reduced.

Adult↗
PubMed1987

IgM antibody production in mice intraperitoneally injected with zirconium oxychloride.

The effect of zirconium (Zr) on the humoral immune response was studied by measuring the level of IgM-plaque forming cells (IgM-PFC) against sheep red blood cells (SRBC) in the spleen of C57 BL mice intraperitoneally injected with zirconium oxychloride. Two experiments, a single injection of zirconium oxychloride of 1/5, 1/10, 1/50, and 1/100 of the LD50 for intraperitoneal injection and continuous injection of 1/20, 1/40, and 1/80 of the LD50 every other day for two or four weeks in mice, were carried out. In the case of a single injection zirconium oxychloride was intraperitoneally injected on days -1, 0, +1, +2, and +3 in relation to SRBC immunisation. The following conclusions may be drawn from this study: (1) Zr was shown to have an adjuvant like activity in relation to the humoral immune response, at least to IgM antibody production; (2) this effect was recognised not only with a single injection with Zr but also after continuous injection; (3) a single injection of Zr was more effective when the mice were treated with Zr 24 hours before or after SRBC immunisation; and (4) with regard to an injected dose of Zr, it was shown that a lower dose (1/50, 1/100 of the LD50 for a single injection and 1/40, 1/80 of the LD50 for continuous injection) led to a more enhanced level of IgM-PFC than a higher dose (1/5, 1/10 of the LD50 for a single injection, and 1/20 of the LD50 for continuous injection).

Animals↗
PubMed1987

[Aplastic anemia and occupational factors in Japanese industries].

Four mail questionnaire surveys were conducted on the incidence of aplastic anemia among industrial workers throughout Japan in collaboration with industrial doctors during a period from 1970 to 1983. The following major results were obtained. 1. Response rates were 55.5% (874/1,574 enterprises) in the first mail questionnaire survey in 1970-1972, 65.3% (294/450) in the second survey in 1973, 49.1% (170/346) in the third survey in 1976-1980, and 76.6% (242/316) in the fourth survey in 1981-1983. There was no significant difference in industrial types among the four surveys. 2. The numbers of aplastic anemia patients newly diagnosed were 145 (112 males/33 females) in the first survey, 21 (16/5) in the second survey, 51 (41/10) in the third survey and 30(24/6) in the fourth survey. Incidence rates per million were 14.7 (14.4 males/15.5 females) in the first and second survey, 14.2 (13.5/18.3) in the third survey and 9.1 (8.6/11.9) in the fourth survey. The rates were almost constant from 1970 through 1980, but the rates decreased thereafter. The rate was higher in females than in males, but the difference was not significant. 3. Incidence rates were high in rubber industry (26.8 per million), paper industry (24.8), and petroleum industry (22.5), but there was no industrial type demonstrating a constantly higher incidence in every survey. Manufacturing industries showed a higher incidence (14.6) than nonmanufacturing industries (11.7). 4. By type of work, non-productive work (67.2%), i.e., clerical (30.8%), administrative (8.9%), technical (7.7%), were the main jobs of 247 registered aplastic anemia patients (193 males and 54 females). 5. Thirty patients had been exposed to noxious agents such as organic solvents (21 cases including 3 exposed to benzene), metals (6), and radiation (1). However, in these cases no causal relationship between exposure and disease onset could be demonstrated. 6. Thirty-nine cases had a drug-intake history before onset of the disease. Drugs given included chloramphenicol (4 cases), other antibiotics (4), antituberculosis agents (8), analgesics (6), and tranquillers (4). The results obtained revealed no positive evidence that occupational factors peculiar to Japanese industries were involved in triggering aplastic anemia.

Adult↗
PubMed1987

[A study on the immunologic effects in workers exposed to low levels of toluene-diisocyanate (TDI)].

Forty-three workers exposed to low levels of toluene diisocyanate (TDI) during the process of producing polyurethane forms were examined immunologically for IgG, A, M, and E and serum enzyme activities such as serum angiotensin converting enzyme (SACE), serum lysozyme (SLZM) and glycylproline dipeptidyl aminopeptidase (GP-DAP). Air concentration of TDI was annually measured in various places of work during the past five years from 1979 to 1983. The results obtained in the present study were as follows. 1. The air concentration of TDI at all places of work was below the permissible concentration level of 0.02 ppm throughout the study period. 2. Subjective symptoms and abnormal findings on chest X-ray considered directly related to TDI exposure were not observed. 3. No remarkable abnormal findings in blood cell counts and in serum biochemical studies could be seen in any of the workers. 4. The serum IgG levels in workers directly exposed to TDI were significantly higher (p less than 0.05) than those in workers indirectly exposed to TDI and in non-exposed workers. 5. In the study of serum enzymatic activity, SLZM activity in workers exposed directly to TDI was significantly higher (p less than 0.01) than those in workers indirectly exposed to TDI and in non-exposed workers.

Adult↗
PubMed1987

Effects of chronic propranolol treatment on hepatic adenylate cyclase system in the rat.

The biochemical aspects of hepatic beta-adrenergic receptors and adenylate cyclase activity in male adult rats were examined during chronic treatment of a beta-adrenergic antagonist, propranolol. The blockade of beta-adrenergic nervous systems for 7 to 10 days produced a considerable elevation of basal, glucagon, sodium fluoride, and 5'-guanylylimidodiphosphate, Gpp (NH)p-stimulated enzyme activity with a negligible response to a beta-adrenergic agonist, isoproterenol. There was no alteration in the density or the affinity of beta-adrenergic receptors for the agonist during the treatment. Guanine nucleotides have failed to induce a transformation of the higher affinity to the lower affinity state of beta-adrenergic receptors of the hepatic membrane derived either from control or the propranolol-treated animals. The activity of stimulatory guanine nucleotide regulatory proteins (Ns) in the enzyme, assessed by ADP-ribosylation was also not altered by the antagonist. These results suggest that the mechanism of the observed sensitization of adenylate cyclase induced by chronic beta-adrenergic blockade involves facilitation of Ns interaction with the catalytic subunit of the enzyme with no change in the beta-adrenergic receptor functions.

Adenosine Diphosphate↗
PubMed1987

Liquid chromatography and radioimmunoassay compared for determination of cortisol and corticosterone in plasma after a dexamethasone suppression test.

We developed sensitive, specific "high-performance" liquid chromatography (HPLC) for determining suppressed cortisol and corticosterone in human plasma and compared its efficacy with that of conventional radioimmunoassay (RIA) at concentrations in the nanogram per liter range. Steroids from a 0.5-mL aliquot of plasma were extracted by rapid-flow fractionation, with diethyl ether as mobile-phase solvent, diatomaceous earth granules as stationary-support material. Analytical recovery of the steroids approached 100%. Concentrations in plasma were determined from peak-height ratio calibration (dexamethasone internal standard). The analytical column contained silica gel and the solvent system was water/methanol/dichloromethane/n-hexane (0.1/3/30/66.9 by vol). We could measure the steroids before and 20 h after oral administration of 0.5 mg of dexamethasone. The detection limit was 300 ng per liter of plasma for corticosterone, 500 ng/L for cortisol, with CVs of less than 4%. Determining corticosterone after administration of dexamethasone, in four of 20 such samples we could determine concentrations greater than 300 ng/L; the others contained corticosterone between 100 and 300 ng/L, but these values could not be certified analytically. Mean concentrations of these hormones as determined by RIA substantially exceeded those by HPLC. Some cross reactions in RIA could not be considered negligible in spite of pre-column treatment of the extracts.

Adult↗
PubMed1986

Inhibition by adenosine of ACTH-stimulated adenylate cyclase and steroidogenesis in the adrenal cortex.

Effects of adenosine analogs on ACTH-stimulated adenylate cyclase activity and steroidogenesis in rat adrenocortical glands have been studied. Adenosine analogs inhibited ACTH-stimulated adenylate cyclase activity by a GTP-dependent process. Methylxanthines reversed the inhibitory effect of N6-phenyl-isopropyl-adenosine (PIA), but not of 2',5'-dideoxy-adenosine. These results suggest that adenosine negatively regulates the stimulation of adenylate cyclase by ACTH at the external and the internal site of the membrane. The inhibitory effect of PIA on ACTH-stimulated steroidogenesis by isolated cells was antagonized by methylxanthines. PIA also inhibited steroidogenesis induced by dibutyryl cAMP, suggesting an inhibitory action of the nucleoside distal to the cAMP system. These results suggest the presence of a common site located in the external membrane for adenosine which subsequently mediates two independent processes, one is negatively coupled to the adenylate cyclase and the other to steroidogenesis for negative feedback controls of the adrenal cortex.

1-Methyl-3-isobutylxanthine↗
PubMed1986

[Behavior of urinary hydroxyproline and the effect of cigarette smoking in silicosis].

This study was conducted through regular pneumonoconiosis examination according to the law on 1,096 employees of medium and small-sized ceramic enterprises in Tokai district in 1981-82. Interview examination with BMRC questionnaire, X-ray examination and measurement of urinary hydroxyproline to creatinine ratio (HOP ratio) were carried out in order to elucidate the relationship between silicosis and urinary HOP ratio and to demonstrate the effect of smoking on pneumofibrosis. Grade of silicosis was classified into five types (0 to 4) based on the Japanese Classification of Radiographs of Pneumoconioses. In evaluating the behavior of urinary HOP ratio, when smoking factor is added in the early grade of pneumofibrosis (type 1 and type 2), collagen decomposition rate is rapidly repressed and fibroplastic conditions develop to the final grade as type 3 and 4, although smoking itself does not seem to induce pneumofibrosis. To exclude the effects of smoking, nonsmoking group was used for measurement of HOP ratio by grade. The HOP ratio in type 0 was lowest and HOP ratio increased in the order of type 1 and type 2. The turning point was found in type 2 and their HOP ratio decreased one after another. The turning point shifted from type 2 to type 3 in the case of non-smokers without any index symptoms by BMRC questionnaire and also shifted to type 1, in the case of non-smokers with them. Shifting of turning point suggests that index symptoms also promote fibroplastic activities.

Adult↗
PubMed1986

[Systemic hyperdynamic circulation and serum hormone concentrations in portal hypertension].

In order to evaluate the pathogenesis of the systemic hyperdynamic circulation in portal hypertension, serum concentration of eight kinds of hormones including glucagon (Glu), aldosterone (Ald), renin (Ren), and epinephrine (Adr), and the hemodynamic parameters were measured in a series of 30 patients, of whom 23 were patients with liver cirrhosis, 3 were with Banti's disease, 2 with chronic active hepatitis, and 2 with pre-cirrhotic change. The average cardiac index was 4.6l/min, m2, with normal PCWP of 6.7 mmHg. CI. and SVR. showed significant inverse correlation of r = -0.767 (p less than 0.01), however, PCWP and CI did not have any significant correlation. Average serum concentrations of Glu, Ald, and Ren were 160 pg/ml, 139 pg/ml, and 5.4 ng/ml, respectively, all of which were increased up to 2.5 times above the normal values. Adr, norepinephrine, cortisol, estrone and estradiol were within normal limits. Of the eight hormones being measured, only Glu had significant correlation with both liver function tests and the cardiac index (r = 0.479, p less than 0.05). Neither Ald nor Adr had significant correlation with hemodynamic parameters.

Adult↗