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Biomedical subjects

M Taniguchi

Publications and source records attributed to M Taniguchi.

At least 685 records · Page 38Linked to original sources
PubMed1987

Possible involvement of Ly-1 B cells in the effector phase of IgG suppression mediated by suppressor T cell factor.

The effector phase of IgG suppression mediated by an antigen-specific suppressor T cell factor (TsF) was studied. The monoclonal TsF of an inducer type derived from a KLH-specific suppressor T cell hybridoma (34S-704) suppressed IgG response mounted by DNP-primed B cells (anti-Thy-1 treated spleen cells) and KLH-specific cloned helper T cells only in the presence of unprimed Thy-1-, Ly-1+, I-J+, Ig+ cells. The addition of naive Ly-1+ cells to the culture of DNP-primed Ly-1/Thy-1 depleted B cells and KLH-Th clones augments anti-DNP IgG responses, and KLH-TsF suppressed the enhanced parts of IgG responses. The Ly-1+ cell seems to be a target of TsF, because naive spleen cells treated either with anti-Ly-1 or with anti-MIg failed to absorb TsF, whereas TsF activity was absorbed with whole spleen cells and anti-Thy-1 treated spleen cells. The functional role of Ly-1 B cells and possible mechanisms in the effector phase of TsF-mediated IgG suppression will be discussed.

Animals↗
PubMed1987

Occurrence of tumor-associated ganglioside antigens with Hanganutziu-Deicher antigenic activity on human melanomas.

The specificity of antibody to NeuGc alpha 2-3Gal beta 1-4Glc-cer (GM3(NeuGc] was carefully reexamined by the method of enzyme-immunostaining on a thin layer plate. The affinity-purified antibody was found to react with NeuGc alpha 2-8NeuGc alpha 2-3Gal beta 1-4Glc-cer (GD3(NeuGc-NeuGc] and NeuGc alpha 2-8NeuAc alpha 2-3Gal beta 1-4Glc-cer (GD3(NeuGc-NeuAc], but not with NeuAc alpha 2-8NeuGc alpha 2-3Gal beta 1-4Glc-cer (GD3(NeuAc-NeuGc)) or NeuAc alpha 2-8NeuAc alpha 2-3Gal beta 1-4Glc-cer (GD3(NeuAc-NeuAc]. From this result together with the previous results, it (GD3(NeuAc-NeuAc], From this result together with the previous results, it could be concluded that the antibody recognizes the outer portion of molecular species of sialic acids in the gangliosides. By using this antibody, the expression of Hanganutziu-Deicher (HD) gangliosides could be demonstrated in human malignant melanoma. The molecular species were different among individuals examined. Among HD-antigenic gangliosides, GM3(NeuGc) was commonly found in melanoma tissues. One of the patients examined expressed GD3(NeuGc-NeuGc) and GD 3(NeuGc-NeuAc), which may be characteristic gangliosides in human melanomas, since these gangliosides could not be detected in human colon cancer or human fetal tissues.

Antigens, Heterophile↗
PubMed1987

Enhancement of host defence by Y-19995 (2,4'-bis(1-methyl-2-dimethyl-aminoethoxyl)-3-benzoylpyridine dimaleate), a novel synthetic compound. I. Accelerated restoration from the leukocytopenia and augmented protection against microbial infections in immunocompromised mice.

Effects of a novel synthetic compound, Y-19995, on the host defence in immunocompromised mice were investigated in terms of the restoration of leukocytopenia and the protection against several microbial infections. Oral or intravenous administration of Y-19995 into mice after X-irradiation, treatment with cyclophosphamide or mitomycin C prevented the leukocytopenia to some extent and promoted the restoration in cell numbers of both the peripheral blood leukocytes and bone marrow. Intravenous administration of Y-19995 increased significantly the survival rates of X-ray irradiated mice against acute systemic infections with Escherichia coli, Pseudomonas aeruginosa and Candida albicans, and intramuscular infection with Escherichia coli. The clearance of Escherichia coli from the blood of X-ray irradiated mice was also promoted by the treatment with Y-19995. The augmented protection against microbial infections in immunocompromised hosts by Y-19995 may be attributed mainly to the prevention of leukocytopenia or the enhanced restoration from leukocytopenia.

Animals↗
PubMed1987

[Surgical indication for extracranial-intracranial arterial bypass determined by cerebral blood flow study and neurological function--a retrospective study].

In order to establish more strict and objective indication for EC-IC bypass, a retrospective study on the surgical effect on cerebral blood flow (CBF) and neurological function was carried out in 37 cases. STA-MCA bypass was carried out on 20 cases with IC occlusion and 17 cases with MCA occlusion. Twenty-two cases with completed stroke, 9 cases with TIA and 6 cases with RIND. All patients were able to ambulate before surgery, and none of them were hemiplegic. CBF study by 133Xe inhalation method was carried out before and 2 to 4 weeks after surgery. Bypass was patent in all cases. Thirty percent of all cases showed more than 16% increase in CBF (++ group) on the side of bypass surgery and another 30% demonstrated 6 to 15% increase (+). On the other hand 30% of cases appeared to be unchanged (+/-), and 10% showed more than 6% decrease (-). The less the pre-operative CBF value was, the more the post-operative CBF was expected to be increased. Patients with pre-operative CBF less than 60% of normal value (ISI = 63 +/- 4) showed remarkable increase (++), and those with 60 to 70% showed moderate increase (+). Contrarily, cases with more than 70% of normal value showed either no change or decrease. Neurological change was evaluated as to disappearance of TIA attack and improvement of hemiparesis or mental dysfunction. Seventy-seven percent of patients in groups with (++) and (+) effect on CBF showed improvement in neurological function, whereas only 27% of patients in groups with (+/-) and (-) effect demonstrated improvement, which was statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain↗
PubMed1987

Enhancement of host defence by Y-19995 (2,4'-bis(1-methyl-2-dimethyl-aminoethoxyl)-3-benzoylpyridine dimaleate), a novel synthetic compound. II. Activation of phagocytic cell functions.

A novel synthetic compound, Y-19995 potentiated phagocytic activity of rat or mouse peritoneal polymorphonuclear leukocytes in vitro or in vivo, respectively. The agent enhanced NBT reducing capacities of rat and guinea pig polymorphonuclear leukocytes in the peripheral blood ex vivo. Y-19995 restored from phagocytic activity of mouse peritoneal macrophages suppressed by the treatment with prednisolone ex vivo. In addition, IL-1 production by mouse macrophages was augmented by culturing with the agent in vitro. Furthermore, Y-19995 potentiated both phagocytic activity and NBT reducing capacity of human peripheral polymorphonuclear leukocytes in vitro. These results suggested that the activation of phagocytic cell functions by Y-19995 contributed to the enhancement of host defence in immunocompromised hosts.

Adjuvants, Immunologic↗
PubMed1987

Differing resistance to polymorphonuclear cells of halophilic- and hypotonic-types of Vibrio vulnificus.

Bacterial growth and lethality of 4 strains of Vibrio vulnificus infection of mice were enhanced by gamma-irradiation but not by treatment with carrageenan. Therefore, protection against V. vulnificus, at least in the early phases, probably depends mainly on polymorphonuclear cells (PMN), since carrageenan depletes macrophages but not PMN. PMN dependent protection against infection differs for 2 types of V. vulnificus strains. Halophilic- and hypotonic-type were distinguished from the corresponding parent strain. The hypotonic-type of the strains had capsular materials, as clarified by electron microscopic observation of the organisms stained with ruthenium red. On the other hand, halophilic-types either had no observable capsular materials, or incomplete materials, in contrast to the corresponding hypotonic-type. The corresponding halophilic- and hypotonic-types of the strains were compared for virulence in mice. The strains with capsular materials acquired resistance to phagocytic activity and were highly lethal. Capsular materials of V. vulnificus are no doubt important for the expression of virulence.

Animals↗
PubMed1986

Phospholipid metabolism in bile duct-ligated rat plasma and erythrocytes.

Incorporation of [32P]orthophosphate into phosphatidylcholine, lysophosphatidylcholine and molecular species of phosphatidylcholine in vivo was observed in liver, plasma and erythrocytes of bile duct-ligated or sham-operated rats. Both the amount and radioactivity of dienoic species of phosphatidylcholine in all tissues examined increased in bile duct-ligated rats as compared to sham-operated rats. The experiments in vivo and in vitro showed that the ratio of lysophosphatidylcholine to phosphatidylcholine transferred to erythrocytes from plasma in sham-operated rats was much higher than that in bile duct-ligated rats. It is suggested that one of the mechanisms by which abnormal erythrocytes appear might be explained by the facilitated and direct transfer of phosphatidylcholine, which is caused by the interaction of erythrocytes with bile acid in bile duct-ligated rat plasma.

Animals↗
PubMed1986

Depression of protective mechanism during the early phase of a viral infection in tumor-bearing mice and prevention by PSK.

Effector mechanisms responsible for resistance against ectromelia virus including antiviral activity of non-immune macrophages, antiviral antibody, delayed footpad reaction to viral antigen, and interferon induction after viral infection were depressed in BALB/c mice bearing syngeneic Meth A tumor. The degree of viral growth correlated well with the depression of delayed footpad reaction, antibody production, and interferon induction. Therefore, modification of macrophage functions by a tumor-bearing state and treatment with PSK may contribute to this modification of antiviral resistance, at an early phase of infection. Cytotoxic activity may not be the principal effector, since the cytotoxicity was induced in normal and tumor-bearing mice to almost the same extent yet an extensive viral growth occurred only in the latter.

Animals↗
PubMed1986

Sequence and expression of transcripts of the T-cell antigen receptor alpha-chain gene in a functional, antigen-specific suppressor-T-cell hybridoma.

We have detected rearrangement and expression of a gene encoding a T-cell antigen receptor alpha chain in the keyhole limpet hemocyanin (KLH)-specific, inducible suppressor-T-cell (Ts) hybridoma 34S-281 (BW5147 lymphoma-C57BL/6Ts) by using alpha-chain cDNA clones isolated from this Ts hybridoma. The cDNA clones have a restriction length polymorphism in the constant region that identifies them as being of C57BL/6 origin. The cDNA sequence has an ATG start codon for an open reading frame including variable, joining, and constant gene segments. Furthermore, the Ts alpha-chain gene transcripts were detected on membrane-bound polysomes by RNA blot analysis using a variable-region fragment from one of the alpha-chain cDNA clones as probe, suggesting that they are actively translated in the Ts hybridoma. As the beta-chain gene is deleted in all Ts hybridomas analyzed, and since a disulfide-linked dimer is detectable by two-dimensional NaDodSO4/PAGE of lysates of surface-radioiodinated Ts, we suggest that Ts antigen receptors are either alpha-chain homodimers or heterodimers composed of the alpha chain in association with an undefined chain.

Animals↗
PubMed1986

Ontogenic changes in metabolism and transport of glutathione in the rat.

Changes in the level of glutathione (GSH), the turnover rate, and gamma-glutamyltransferase (GGT) activity were examined in newborn, weanling, and adult male Wistar rats, the objective being to elucidate the mechanisms which control the hepatic GSH level during maturation as well as under conditions of different degrees of protein ingestion. The hepatic GGT activity in the newborn rats was high at birth, decreased within a few days to 1 to 2% of the initial level, and remained unchanged thereafter, when these rats were fed a normal diet after 3 weeks of age. In contrast, the hepatic GSH level increased 3-4-fold while total GGT activity in the kidney increased 6-8-fold. When weanling rats were fed a low protein diet (containing 10% soy protein) for 3 weeks, the hepatic GSH level decreased markedly while the GGT activity increased 5-6-fold. The turnover rate of hepatic GSH also increased, as determined by the use of buthionine sulfoximine, a specific inhibitor of GSH synthesis; a value of 2.1 h was obtained in comparison with 3.5 h for that of rats fed the normal laboratory chow (CRF-1). On the other hand, feeding adult rats on the low protein diet resulted in a marked decrease in hepatic GSH level with no effect on either hepatic or renal GGT activity. These results together with other observations may suggest that GSH translocated out of liver cells in the newborn rats is degraded mainly by these cells, while the tripeptide secreted by hepatocytes of adult rats is metabolized predominantly in extrahepatic tissues, such as the kidney.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1986

Functional mapping of ventricular contraction and phase using single-photon emission computed tomography (SPECT).

A method for functional mapping of ventricular contraction and phase was developed using gated blood-pool SPECT. Parameters of contraction and phase were calculated using length-based and count-based Fourier analyses. In length-based Fourier analysis (LFA), percentage-shortening and length-based phase were calculated based on the changes of lengths from a ventricular centre to edges. In count-based Fourier analysis (CFA), phase and amplitude were also calculated using serial tomographic phase images. Two-dimensional polar display format was employed to summarize the SPECT data of whole cardiac surface. This program was applied to evaluate coronary artery disease and conduction anomalies. The polar functional map using gated blood-pool SPECT can be an effective method to integrate three-dimensional cardiac information in conjunction with myocardial SPECT studies.

Erythrocytes↗