Kazuo Ryoyama

Learn More
Based on the observation that spleen cells from Adriamycin-treated mice could develop augmented levels of cytotoxic T-lymphocyte activity in response to heat-treated and/or X-irradiated alloantigens, it was postulated that modulations in soluble mediators could be involved in this phenomenon. In fact, in this study Adriamycin-induced increases in the levels(More)
The cellular basis for the augmented cell-mediated cytotoxic (CMC) response seen when spleen cells from Adriamycin (ADM)-treated mice were stimulated in culture was investigated. Under conditions where mature macrophages were reduced (adherent or silica-sensitive cells removed) at time of alloantigen challenge, the cells from ADM-treated mice developed(More)
C57B1/6 mice were injected i.v. with Adriamycin (5 mg/kg) and various days later, spleen cells were tested for Fc dependent phagocytic activity by measuring protection of 51Cr-labelled, antibody coated SRBC from hyptonic shock. No difference in phagocytic activity was observed with spleen cells from untreated mice or mice treated with Adriamycin 1-7 days(More)
There is increasing demand for novel anti-inflammatory drugs with different mechanisms of action. We synthesized a series of isothiocyanates 2b-h based on 6-(methylsulfinyl)hexyl isothiocyanate (6-MITC) found in the pungent spice Wasabia japonica. Inhibitory activities against in-vitro growth of tumor cells and production of nitric oxide (NO) using the(More)
Serum-free mouse embryo (SFME) cells, the astrocyte progenitor cells in the central nervous system, generated a self-sustaining feedback loop for glial fibrillary acidic protein (GFAP) expression after a period of cell passages. The period required was about 150 days (30 passages). SFME and high-GFAP-expressing SFME (G-SFME) cells were exposed to 10 ng/ml(More)
Oral administration of an enzymatically synthesized alpha-1,4:1,6-glycogen (ESG) at a dose of 50 mug/ml significantly prolonged the survival time of Meth A tumor-bearing mice. ESG also significantly stimulated macrophage-like cells (J774.1), leading to augmented production of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha). The weight-average(More)
AIM Effect of oral administration of 6-(methylsulfinyl)hexyl isothiocyanate (6-MITC) or a 6-MITC-containing T-wasabi fraction from wasabi root (Wasabia japonica Matsum) to inhibit the macroscopic pulmonary metastasis was studied with a murine B16-BL6 melanoma model. METHOD Two administration routes, subcutaneous or intravenous, and two administration(More)
Ras/myc-transformed serum-free mouse embryo (ras/myc SFME) cells were treated with interferon-gamma (IFN-gamma, 100 units/ml) and/or lipopolysaccharide (LPS, 0.5 microg/ml) for 24 h to investigate the effects of these ligands on the expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1). Aminoguanidine (AG,(More)
To induce peptide-specific antibodies in mice, as a model for vaccination against human immunodeficiency virus (HIV), lipopeptide analogs conjugated with three repeating units (KAB-112; designated as gp120-peptide) of a part (Gly-Pro-Gly-Arg-Ala-Phe) of the amino acid sequences of the V3 loop region in gp120 of HIV were synthesized. The mitogenicity,(More)
The present study was designed to determine whether antitumor activity of macrophages induced with OK-432 and cyclophosphamide was mainly dependent on their ability to produce a soluble factor, that is,l-arginine-dependent nitric oxide as measured by nitrite concentration. Nitrite production by peritoneal macrophages from NIH Swiss mice pretreated with(More)