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Biomedical subjects

T Taniyama

Publications and source records attributed to T Taniyama.

At least 55 records · Page 3Linked to original sources
PubMed1991

Studies on absorption, distribution, excretion and metabolism of ginseng saponins. VII. Comparison of the decomposition modes of ginsenoside-Rb1 and -Rb2 in the digestive tract of rats.

In order to clarify some similarities and differences of decomposition modes between 20(S)-protopanaxadiol (20(S)-ppd) saponins, represented by ginsenoside Rb1 (Rb1) and ginsenoside Rb2 (Rb2), the decompositions of Rb1 and Rb2 in the rat gastrointestinal tract, 0.1 N HCl and crude hesperidinase were investigated in detail. As in the case of Rb2 reported previously, Rb1 was hydrolyzed to 20(R,S)-ginsenoside Rg3 in 0.1 N HCl. On the other hand, hydroperoxidation of Rb1 occurred in rat stomach; the major hydroperoxide was separated and identified as the 25-hydroperoxy-23-ene derivative of Rb1 (VIII) by 1H- and 13C-nuclear magnetic resonance and fast atom bombardment mass spectrometry. The decomposition modes of 20(S)-ppd saponins (Rb1 and Rb2) differed from that of 20(S)-protopanaxatriol saponin (Rg1) in rat stomach. In rat large intestine, five decomposition products of Rb1 were observed by thin-layer chromatography, and these were identified as gypenoside XVII (G-XVII), ginsenoside Rd (Rd), ginsenoside F2 (F2), compound K (C-K) and VIII. The decomposition modes of Rb1 and Rb2, both 20(S)-ppd saponins, are considered to be different because of the hydrolysis rate in the terminal sugar moiety at the C-20 hydroxyl group in the rat large intestine. Using crude hesperidinase, Rb1 was decomposed to G-XVII, F2 and C-K, and Rb2 was decomposed to 3-O-beta-D-glucopyranosyl-20-O-[alpha-L-arabinopyranosyl(1----6)-b eta-D- glucopyranosyl]-20-(S)-ppd, F2 and C-K. Consequently, it appears that hydrolysis by beta-glucosidase, which is present in the rat large intestine, is distinct from that by crude hesperidinase.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Studies on absorption, distribution, excretion and metabolism of ginseng saponins. VI. The decomposition products of ginsenoside Rb2 in the stomach of rats.

The decomposition of ginsenoside Rb2 (Rb2) in rat stomach (in vivo) and in 0.1 N HCl solution (in vitro) was investigated in detail. By treating with 0.1 N HCl, the acidity of which is similar to that of gastric juice, a part of Rb2 was hydrolyzed to 20(R,S)-ginsenoside Rg3. On the other hand, Rb2 was little decomposed in rat stomach and a small quantity of an unidentified metabolite, which was different from the hydrolyzed products in 0.1 N HCl, was observed. The metabolite was separated into four compounds, which were identified by 1H- and 13C-nuclear magnetic resonance and fast atom bombardment mass spectrometry. These compounds were determined to be 25-hydroxy-23-ene (IV), 24-hydroxy-25-ene (V), 25-hydroperoxy-23-ene (VI) and 24-hydroperoxy-25-ene (VII) derivative of Rb2, respectively. In this study, it is suggested that 20(S)-protopanaxatriol saponins undergo hydrolysis of the C-20 glycosyl moiety and hydration of the side chain, on the other hand, 20(S)-protopanaxadiol saponins undergo oxygenation of the side chain.

Absorption↗
PubMed1990

Production of antitumor mononuclear blood cells in tumor-bearing mice by interferon-alpha A/D therapy.

Administration of human interferon-alpha A/D (IFN-alpha A/D) to Meth A fibrosarcoma-bearing mice produced mononuclear blood cells with antiproliferation activity that were able to suppress Meth A growth in vitro. Their production depended on IFN doses and administration intervals. They were short-lived since antiproliferation activity was not detectable in mononuclear cells 2 days after cessation of IFN administration, although it was detectable as long as IFN administration continued. A similar production of antiproliferative mononuclear blood cells by IFN was achieved in tumor-free as well as in tumor-bearing mice, indicating no deleterious effect of the growing tumor on the production of these cells. IFN-induced antiproliferation activity was not tumor-specific since mononuclear blood cells of IFN-administered mice bearing either Meth A and Meth 1, another antigenically distinct fibrosarcoma, suppressed the in vitro growth of both Meth A and Meth 1 cells. T cells were not involved in the in vivo production of antiproliferative mononuclear blood cells by IFN therapy because the cells with this activity were produced in vivo in Meth A-bearing athymic mice and also in Meth A-bearing mice with reduced T-cell populations by the treatment with alpha mouse thymocyte globulin. T cells were not involved in their antiproliferation activity either, since the in vitro T-cell depletion of mononuclear cells did not diminish this antiproliferation activity. Because mononuclear cells surviving the in vitro T cell depletion were positive for AcM.1 (an epitope of activated macrophage) and also because the alpha Mac-1 antibody completely abolished their in vitro antiproliferation activity, this led us to conclude that it was activated monocytes in blood that were produced by IFN in a T-cell-independent fashion and that these monocytes were the cells responsible for the observed in vitro antiproliferation activity.

Animals↗
PubMed1990

Studies on absorption, distribution, excretion and metabolism of ginseng saponins. V. The decomposition products of ginsenoside Rb2 in the large intestine of rats.

The decomposition of ginsenoside Rb2 (Rb2) in the rat large intestine after oral administration was investigated in detail. A part of Rb2 was decomposed and six decomposition products (I-VI) were observed on thin-layer chromatogram. Among them, five products (I-V) were isolated, and identification of these compounds was done by carbon-13 nuclear magnetic resonance (13C-NMR). On the basis of 13C-NMR analysis, these compounds were identified as ginsenoside Rd (I), 3-O-beta-D-glucopyranosyl-20-O- [alpha-L-arabinopyranosyl(1----6)-beta-D-glucopyranosyl]-20(S)- proto-panaxadiol (II), ginsenoside F2 (III), 20-O-[alpha-L-arabinopyranosyl(1----6)-beta-D-glucopyranosyl]-20(S )- protopanaxadiol (IV), and compound K (V), respectively.

Animals↗
PubMed1990

Constitutive production of novel macrophage-activating factor(s) by human T cell hybridomas.

Human T cell hybridomas were constructed by somatic cell fusion in order to dissect molecular heterogeneity of human macrophage activating-factors (MAF). Two stable human hybridoma supernatants contained MAF activity capable of inducing human monocytes tumoricidal without the help of bacterial lipopolysaccharide (LPS). These supernatants in the presence of LPS could also render mouse macrophages tumoricidal. In contrast, recombinant and natural human interferon-gamma (Hu-IFN-gamma) activated human monocytes, but not mouse peritoneal macrophages. The supernatants from the two clones could neither support the growth of human-granulocyte-macrophage colony stimulating factor/human-interleukin-4-dependent (Hu-GM-CSF/Hu-IL-4) cell lines, such as AML 193 and TALL-101, nor stimulate the proliferation of human-interleukin-2-dependent human cell line and lectin-stimulated lymphoblast, which are responsive to human-interleukin-2 and human-interleukin-4. Rabbit or murine antibodies against human-interferon-gamma (Hu-IFN), human-granulocyte-macrophage colony stimulating factor, human interleukin-1 alpha, human-interleukin-1 beta, human-interleukin-6, human-tumour necrosis factor (Hu-TNF), human-lymphotoxin and human-macrophage migration inhibitory factor (Hu-MIF) could not absorb MAF activity. MAF activity in the hybridoma supernatants is associated with the two polypeptides of molecular weights of 70,000-80,000 and 20,000-30,000 daltons, as determined by gel filtration. These results indicate decisively that novel MAF molecule(s) is secreted by human T cell hybridomas.

Animals↗
PubMed1990

[Abrupt onset and rapid deterioration in the course of congenital ornithine transcarbamylase deficiency: a case report].

We report a 17-year-old female case of ornithine transcarbamylase (OTC) deficiency who died of brain edema due to hyperammonemic attack. The patient had a brother with OTC deficiency who had died of hyperammonemia at 17 years of age. She firstly had a symptom of headache, nausea, vomiting and myalgia at 14 years old and twice thereafter. On admission she had a severe disorientation and vomiting. The plasma ammonia level was 89 micrograms/dl, then increased to 400 micrograms/dl in five hours. In addition to plasma exchange, hemodialysis and then peritoneal dialysis for next 5 days, parenteral sodium benzoate and arginine were administered. Although the plasma ammonia level improved gradually, her consciousness never returned and she died of severe brain edema with uncontrollable hypotension on day 8. Histology of a necropsy liver sample showed fatty metamorphosis of hepatocytes mainly with fine lipid droplets. Electron micrograph of hepatocytes showed crystalloid inclusions in mitochondria. Significance of the clinical course and the treatment during hyperammonemic crisis was discussed.

Acute Disease↗
PubMed1989

Contribution of IL-6 to the antiproliferative effect of IL-1 and tumor necrosis factor on tumor cell lines.

The role of IL-6 in the antiproliferative effect of IL-1 for tumor cell lines was investigated using IL-1-sensitive cell lines. Human recombinant IL-1 alpha and IL-6 both inhibited the growth of an IL-1-sensitive cloned human melanoma cell line (A375-C6). However, IL-1 has greater maximum growth inhibitory activity than IL-6. Conditioned medium of the tumor cells that were treated with IL-1 contained IL-6 as determined by ELISA. Northern blot analysis revealed that IL-6 mRNA expression increased in IL-1-treated cells. In addition, antibody against human IL-6 neutralized about 50% of the antiproliferative effect of IL-1. The growth of an IL-1-resistant clone of A375 cells (A375-C5), which cannot be shown to express any detectable IL-1R, was inhibited by IL-6 to the same degree as A375-C6 cells. The A375-C5 cell line did not produce IL-6 or increase IL-6 mRNA after stimulation with IL-1. These results indicate that IL-6 mediates in part the antiproliferative effect of IL-1 on A375-C6 cells by acting as an autocrine antiproliferative factor. IL-1 also inhibited the growth of a malignant human mammary cell line (MDA-MB-415). IL-6 exhibited only slight growth inhibition in this cell line. Neither IL-6 production nor IL-6 mRNA expression was induced in this cell line by IL-1. Antibody against IL-6 did not neutralize the antiproliferative effect of IL-1. Therefore, for MDA-MB-415 cells IL-6 appeared not to be involved in the antiproliferative effect of IL-1. These results indicate that the antiproliferative effect of IL-1 involves at least two pathways, one IL-6 dependent and another IL-6 independent. The contribution of IL-6 to the antiproliferative effect of TNF was also examined. IL-6 appeared not to play a role in the antiproliferative effect of TNF in these cell lines.

Animals↗
PubMed1989

Synergistic regulatory effects of interleukin 6 and interleukin 1 on the growth and differentiation of human and mouse myeloid leukemic cell lines.

We analyzed the effect of recombinant human interleukin 6 (IL-6), in combination with human recombinant interleukin 1 alpha (IL-1 alpha), on the growth and differentiation of several human and mouse myeloid leukemic cell lines, specifically U937, HL-60, M1, and its subclone M1-3b-N, into macrophage-like cells. IL-6 and IL-1 inhibited the growth of U937, M1, and M1-3b-N in a dose-dependent manner. Treatment of these cells with both IL-6 and IL-1 resulted in either an additive or a synergistic growth inhibition. IL-6 alone induced moderate differentiation of U937 and M1-3b-N, but the combination of IL-6 and IL-1 synergistically augmented this differentiation. In M1, only the combination of IL-1 and IL-6 resulted in differentiation. These two cytokines, whether alone or in combination, did not influence the growth and differentiation of HL-60. Therefore IL-6 in conjunction with IL-1 can induce differentiation in several human and mouse myeloid leukemic cell lines, although this effect varies with cell type. IL-6 did not stimulate the expression of IL-1 mRNA or IL-1 activity in U937 cells. IL-1 also failed to stimulate IL-6 production. Furthermore, the differentiation of U937 cells induced by IL-6 was not neutralized by antibody against either IL-1 alpha or IL-1 beta. The minimal differentiative effect of IL-1 was not affected by anti-IL-6 antibody. Therefore IL-6 and IL-1 appear to provide distinct signals for differentiation.

Animals↗
PubMed1989

Dose-dependent regulation of macrophage differentiation by mos mRNA in a human monocytic cell line.

The proto-oncogene c-mos was expressed during differentiation of the human monocytic cell line U937 into macrophages. To investigate a possible role of the mos oncogene, we introduced the v-mos gene under an inducible promoter, MT-I, into U937 cells. The v-mos transformed cells expressed mos mRNA at an amount proportional to the concentration of Zn2+ ions. The induction of the v-mos gene caused growth inhibition and macrophage differentiation in these cells. The differentiation of v-mos transformed monocytes into macrophages required continuous expression of the v-mos gene. The extent of expression of phenotypic characteristics of macrophages, such as phagocytosis, cell surface antigens and typical morphology, depends on the amount of mos mRNA present. We were therefore able to demonstrate that the expression of only one oncogene, mos, determines monocyte differentiation into macrophages.

Antigens, Surface↗
PubMed1989

Exogenous expression of mouse interferon gamma cDNA in mouse neuroblastoma C1300 cells results in reduced tumorigenicity by augmented anti-tumor immunity.

To examine the influence of interferon gamma (IFN-gamma) on tumorigenicity, we established constitutively IFN-gamma-producing cell lines from a malignant mouse neuroblastoma, C1300, by retroviral transfer of a mouse IFN-gamma cDNA. The gene-transferred cells generally showed an enhanced high-level expression of the major histocompatibility complex class I antigens at the cell surface and the transcription levels, irrespective of their IFN-gamma-producing potential. Although in vitro cell growth of these cells was unaffected by the IFN-gamma production, their s.c. tumor growth in syngeneic A/J mice was dependent upon levels of IFN-gamma production; tumors induced by a low-producer line grew well at a rate similar to those induced by the parental one, but tumor growth of a high-producer line was strongly suppressed. This apparent tumor suppression was abolished by simultaneous i.p. injection of anti-Lyt2.2 and/or anti-IFN-gamma monoclonal antibodies, and subsequently large tumors of the high producer were generated. Anti-asialoganglioside GM1 antibodies allowed the high-producer line to induce a substantial but only transient tumor growth, whereas other antibodies, such as anti-Lyt2.1, anti-IFN-beta, and anti-activated macrophage, had no such effect. The mice immunized with the high-producer line were resistant to tumor growth of the parental cells but permitted another kind of A/J tumor line, Sa-1, to induce remarkable tumors. These results indicate that the reduced tumorigenicity of the IFN-gamma high-producer line was due to the augmented specific anti-tumor immunity, in which cytotoxic T lymphocytes seemed to play a decisive role, probably as a result of the immunomodulatory effects of the IFN-gamma derived from the tumor.

Animals↗
PubMed1989

Monoclonal antibodies that specifically inhibit GM-CSF- and IL-3-dependent growth of human monocytic leukemia cells.

We describe monoclonal antibodies (mAbs: anti-MaG-1, TGI-1, TGI-5, and TGI-6) that block the proliferation of AML-193 cells in response to GM-CSF or IL-3 and do not affect the proliferation of AML-193 cells in response to G-CSF and IL-2-driven proliferation of Kit 225 cells. However, none of the mAbs tested had any stimulative effect on the proliferation of AML-193 cells. The mAbs (anti-MaG-1, TGI-1, -5, and -6) could inhibit the binding of [125I]GM-CSF to AML-193 cells. We were able to purify MaG-1 Ag by anti-MaG-1 affinity chromatography. Thus, the MaG-1 Ag and the Ags recognised by mAbs (TGI-1, -5, and -6) may be associated with the receptor for GM-CSF or IL-3 or a structure close to the receptor for GM-CSF or IL-3.

Animals↗
PubMed1989

Separation of rosette formation-inducing polypeptides from the supernatant of cultures of rat thymic epithelial cell line.

Four polypeptide fractions were isolated by high-pressure liquid chromatography (HPLC) from culture supernatant of rat thymic epithelial cell line (IT-45R1). Biological activity of these fractions was examined according to the capacity inducing rosette-formation between rat thymocytes and guinea pig erythrocytes. A relatively rich population of non-rosette-forming cells (non-RFC), one of targets for thymic hormones, was separated from rat thymocytes by combining rosette-formation method with differential centrifugation. Non-RFC consists of outer-cortical and medullary thymocytes. Medullary thymocytes treated with the polypeptide fraction did not differentiate into RFC. Therefore, the cells, which rosette-forming capacity was induced, seem to derive from outer-cortical area. One of the polypeptide fractions (estimated molecular weight: 3 K) possessed the activity endowing non-RFC with rosette-forming capacity. Since its molecular weight was similar to that of thymosin alpha 1, the fraction was pretreated with anti-thymosin alpha 1 antiserum. The pretreatment suppressed the activity of the fraction. Thus, the fraction must contain thymosin alpha 1 or a polypeptide possessing an antigenic determinant similar to that of thymosin alpha 1. Moreover, two of four subfractions, which were divided from the active fractions by reversed-phase HPLC, showed the biological activity.

Animals↗
PubMed1988

Demonstration of a novel tumor-killing factor secreted from human macrophage-monocyte hybridomas.

We constructed human macrophage-monocyte hybridomas between a thymidine kinase-deficient human macrophage-like cell line, designated as TAM-2, and human peripheral blood monocytes in order for the study of cytokines from human monocytes. The hybrid and macrophage-monocyte nature of the growing cells was confirmed by the following facts: 1) All of the hybridomas established possess TK activity, whereas the TAM-2 cells are TK negative. 2) Most but not all of the hybridomas express the MaG-1 Ag which was shown to be a human macrophage-granulocyte specific Ag, but not T- and B-specific Ag. In the assay for cytokine, a few of the hybridomas produced a novel tumor-killing factor (TKF) after stimulation with PMA, polypeptone, and retinoic acid. Chemical nature of the TKF from the 3-63 hybrid clone was characterized and compared to those of well-known TNF and lymphotoxin. The TKF from a hybridoma was basic protein and had binding capacity to Con A-Sepharose, whereas TNF had an opposite nature. Moreover, TKF activity was not neutralized by both a murine monoclonal antibody against human TNF and rabbit antisera against human lymphotoxin. Thus, these results strongly indicate that the TKF is a novel TKF produced by human monocytic cells.

Cell Fusion↗
PubMed1988

Recombinant human interleukin 6 (B-cell stimulatory factor 2) is a potent inducer of differentiation of mouse myeloid leukemia cells (M1).

Recombinant human interleukin 6 (IL-6), a lymphokine involved in the final differentiation of activated B-cells into antibody-forming cells, greatly suppressed proliferation and induced differentiation of murine myeloid leukemia cells (M1) into mature macrophage-like cells. When M1 cells were treated with IL-6, their growth was completely arrested as early as on day 2, and they were induced to differentiate morphologically into macrophage-like cells. Differentiation-associated properties such as phagocytic activity, adherence to the dish surface, Fc and C3 receptors, were also induced within 24 h by IL-6, and they reached their respective maximal levels on day 2 or 3. The potency of IL-6 in suppressing proliferation and inducing differentiation was much greater than that of 1 alpha,25-dihydroxyvitamin D3 one of the most potent inducers of M1 cells. The present report indicates that IL-6 is involved in the differentiation of not only B-cells but also myeloid leukemia cells.

Animals↗