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Biomedical subjects

F Suzuki

Publications and source records attributed to F Suzuki.

At least 595 records · Page 33Linked to original sources
PubMed1979

Induction by parathyroid hormone of ornithine decarboxylase in rabbit costal chondrocytes in culture.

The activity of ornithine decarboxylase (ODC) in rabbit costal chondrocytes in culture markedly increased after addition of parathyroid hormone (PTH), reaching a maximum 4 to 5 h after PTH addition. The effect of PTH was dose-dependent both in the presence and absence of fetal calf serum. Addition of cycloheximide or actinomycin D prevented the induction of ODC by PTH. Calcitonin, 1,25-dihydroxyvitamin D3, and vitamin A had no stimulatory effect on the activity of ODC, and did not inhibit the induction of ODC by PTH, when added with PTH.

Animals↗
PubMed1979

Antiviral and interferon-inducing activities of a new peptidomannan, KS-2, extracted from culture mycelia of Lentinus edodes.

Oral (PO) administration of KS-2 to adult DDI mice resulted in a peak serum interferon (IF) titer of 800 units (U)/ml 20 hours after administration with detectable levels persisting until 30 hours. After intraperitoneal (IP) injection, a peak serum IF titer of 1,600 U/ml was detected and it followed the same time course as that of oral administration. The IF induced by KS-2 shared certain physico-chemical properties with the standard preparation of immune IF and was not neutralized by an antiserum against type I IF. In mice infected intranasally (IN) with influenza A2 (H2N2) virus, KS-2 was found to possess significant protective activities. Efficacy of the agent was evidenced by an increase in survivor number, a prolongation of mean survival time, an inhibition of the development of lung consolidation induced by the viral infection and a decrease in virus titer in lung tissues. Both PO and IP administrations of KS-2 protected mice against infection and significant antiviral activities were achieved not only by prophylactic but also chemotherapeutic administration. The protective activities of KS-2 against influenza virus infection in mice are discussed in view of the immunopotentiation of the host animals.

Agaricales↗
PubMed1979

Evaluation of a solid-phase enzyme immunoassay for insulin in human serum.

We describe a "sandwich-type" enzyme immunoassay for insulin in serum, in which antibody Fab'-beta-D-galactosidase conjugate and an antibody-immobilized silicone rubber solid-phase are used. The interference by serum factors with the solid-phase enzyme immunoassay can now be removed by using a buffer containing gelatin. Serum samples of 50 microL can be analyzed by the enzyme immunoassay, which is as sensitive as radioimmunoassay for human insulin. Our results correlate well with those for radioimmunoassay (r = 0.97, slope = 0.92, y-intercept = 4.6 milli-int. units /L for 181 samples). Between-assay and within-assay coefficients of variation are less than 15% over the useful ranges of the assay (5--160 milli-int. units/L).

Evaluation Studies as Topic↗
PubMed1978

Cell to cell relationships in the seminiferous epithelium in the mouse embryo.

Germ cells and Sertoli cells in embryonic mouse testes (day 14 to 20 of gestation) were examined by sectioning and freeze-fracture. Intercellular cytoplasmic bridges between the germ cells are observed in day 14 and older embryos. Membrane specializations with dense fuzzy material similar to the so-called "desmosome-like structures" are found between Sertoli cells and germ cells. A cell contact area with dense opposed membranes is also found between adjacent germ cells. Asymmetrical dense fuzzy lining of both Sertoli and germ cell membranes is noted. Pinocytotic pits or caveolae are frequently found in the Sertoli cell membrane. Between adjacent Sertoli cells, gap junctions of various sizes and focal meshworks of the occluding junctions are found. Most of the occluding junctional particles are located in the center of the grooves in the E face, and are similar to those in postnatal and adult Sertoli cell junctions. In addition, on both fractured faces there are ridges and grooves devoid of particles which are continuous with occluding junctions with particles, suggesting an initial stage in the formation of occluding junctions of the Sertoli cells. Particles gathered at the site of desmosome-like structures are present on the P face of the Sertoli cell.

Animals↗
PubMed1978

Demonstration of somatomedin activity of "multiplication-stimulating activity" in rabbit costal chondrocytes in culture.

Multiplication-stimulating activity (MSA), a substance obtained from conditioned medium of Buffalo rat liver cells, stimulated replication of rabbit costal chondrocytes in culture and their DNA synthesis, sulfation of glycosaminoglycans, protein synthesis, and collagen synthesis. These stimulatory effects of MSA were dose-dependent in serum-free medium, indicating that MSA has intrinsic somatomedin activity. Even after several successive passages, cultured chondrocytes were more responsive to MSA than other organ- and cell-culture systems reported. Therefore, cultured rabbit costal chondrocytes proved a good in vitro system for analysis of somatomedin actions.

Animals↗
PubMed1978

Effect of an interferon inducer, 9-methylstreptimidone, on Candida albicans infection in mice.

The protective effect of an interferon inducer with a low molecular weight, 9-methylstreptimidone (9-MS), against Candida albicans infection in mice was investigated. The antibiotic was effective only when given prophylactically. When administered in such a manner, the growth of C. albicans in the kidneys and brain was inhibited at the initial stage of infection. The growth of C. albicans was not inhibited by the antibiotic in vitro, and no antifungal effect was obtained in a preparation containing induced interferon. These results suggest that the antifungal action of 9-methylstreptimidone in mice might be manifested not by direct antifungal activity but rather by a host-mediated activity that excludes interferon-inducing capability.

Animals↗