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Biomedical subjects

S Arai

Publications and source records attributed to S Arai.

At least 433 records · Page 24Linked to original sources
PubMed1981

Role of cell-mediated hypersensitivity in budgerigar breeder's lung.

Eight subjects who possessed precipitating antibodies against budgerigar serum and budgerigar dropping extracts were investigated for the reactivity of their lymphocytes to the antigen. Lymphocytes from the five symptomatic breeders were significantly stimulated by budgerigar serum, but lymphocytes from the three asymptomatic breeders were not stimulated by this antigen, even though both groups showed precipitating antibodies. To investigate the participation of the T-cell response against budgerigar serum, the peripheral blood lymphocytes were fractionated into T-cells, B-cells and monocytes. Only the T-cells responded to the antigen when the monocytes were present. We concluded from these studies that the T-cell-mediated immune response together with a significant contribution from the monocytes plays an important role in the pathogenesis of bird breeder's lung.

Adult↗
PubMed1981

Activation of human T and non-T lymphocytes by sepharose-bound concanavalin A and the differential effect of macrophages.

The mitogenic effect of insoluble concanavalin A (Con A) bound to Sepharose beads on human peripheral blood mononuclear cells has been investigated. Sepharose-Con A, with a maximum activity at 100-400 micrograms/ml and an optimal incubation time of 3 or 4 days, stimulated the mononuclear cells with a high mitogenic response. Sepharose-Con A also stimulated the monocyte-depleted lymphocytes and their T- and non T-enriched fractions with a definite mitogenic response, although the levels of response were much lower than those of unpurified mononuclear cells. Addition of the adherent monocytes strongly augmented the Sepharose-Con A responses of monocyte-depleted lymphocytes and their T-enriched fractions, whereas it gave no effect on those of non-T-enriched fractions. Culture fluids of adherent monocytes also augmented the Sepharose-Con A responses of monocyte-depleted lymphocytes. These results indicate that, although insoluble Sepharose-Con A activates both human T and B cells, the response of T cells but not B cells may be dependent in part on the presence of monocytes or a monocyte-derived soluble factor(s). Thus, it is concluded that Sepharose-Con A may be a useful mitogen to elucidate the role of macrophages or their soluble factors in activation of human T and B cells.

Cell Separation↗
PubMed1981

Inhibition of mouse natural killer activity by cholera toxin.

The treatment of mouse spleen cells with cholera toxin (CT) extracted from Vibrio cholerae greatly reduced natural killer (NK) activity. The inhibition of NK activity was rapidly induced by CT treatment and persisted in the absence of CT. Even a very small amount of CT, such as 0.1 ng/ml, was effective in inhibiting NK activity. The inhibitory effect of CT on NK activity was lost upon preabsorption of CT with brain tissues, but not upon preabsorption with liver or kidney tissues.

Animals↗
PubMed1980

In vitro antimicrobial activity of cefotaxime, a new cephalosporin.

Cefotaxime, a new semisynthetic cephalosporin derivative, showed a broad spectrum of antibacterial activity against clinically isolated strains of gram-positive and gram-negative bacteria. This cephalosporin was slightly less active than cefazolin against Staphylococcus aureus but 4 to 300 times as active as carbenicillin against gram-negative organisms, including Pseudomonas aeruginosa, Pseudomonas cepacia, Enterobacter cloacae, and Serratia marcescens. Cefotaxime was the most active compound against members of the Enterobacteriaceae and 20- to 100-fold more active than cefoxitin against the indole-positive Proteus group. The minimal bactericidal concentrations of the compound were identical to, or two times higher than, the minimal inhibitory concentrations against Escherichia coli and P. aeruginosa and four times higher against S. marcescens. A reduction of inoculum size decreased greatly the minimal inhibitory and bactericidal concentrations of cefotaxime against E. coli P. aeruginosa, and S. marcescens. The antibiotic was very stable to penicillinase and cephalosporinase produced by gram-negative bacteria, including Proteus vulgaris.

Anti-Bacterial Agents↗
PubMed1980

[Evaluation of stat assay of serum digoxin concentration by radioimmunoassay and its application for digoxin regimen based in pharmacokinetics (author's transl)].

Serum digoxin concentration measured by stat RIA (phadebas digoxin RIA kit) correlated well with results obtained by complete assays. The results of stat assay can be reported within 1 hour, measuring one or more samples together with 2 standard samples in duplicates. Precise measurement can be expected with serum digoxin concentration over 0.5 ng/ml. The stat assay allows to apply the theory of pharmacokinetics for the estimation of digoxin concentration at steady states measuring minimum digoxin concentration (Cn(min)) on the 3rd to 6th day after the start of digoxin therapy. The estimated serum digoxin levels were well agreed with measured values with the difference ranging from 1.6 to 8.6% in CV. The method is useful for the planning and assessment of appropriate digoxin regimen.

Aged↗