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T Taki

Publications and source records attributed to T Taki.

At least 271 records · Page 15Linked to original sources
PubMed1981

Further characterization of the structure of GM1b ganglioside from rat ascites hepatoma.

A ganglioside named GM1b (Hirabayashi, Y., Taki, T., and Matsumoto, M. (1979) FEBS Let. 100, 253-257) with a sugar composition identical with that of GM1, II3 alpha NeuAc-GgOse4Cer (Gal beta 1 leads to 3GalNAc beta 1 leads to 4Gal(3 leads from 2 alpha NeuAc) beta 1 leads to 4G1c beta 1 leads to 1'ceramide), isolated from rat ascites hepatoma was further characterized. In contrast to GM1, the sialic acid in this ganglioside was susceptible to clostridial sialidase in the absence of bile salts. Based on the sequential enzymic hydrolysis, permethylation analysis and direct probe mass spectrometric analysis, the structure of this ganglioside is determined to be: NeuAc alpha 2 leads to 3Gal beta 1 leads to 3GalNAc beta 1 leads to 4Gal beta 1 leads to 4Glc leads to ceramide. The structure of this ganglioside is identical with that biosynthesized in vitro (Stoffyn, A., Stoffyn, P., and Yip, M. C. M. (1975) Biochim. Biophys. Acta 409, 97-103).

Animals↗
PubMed1981

Purification of anti-glycosphingolipid antibody and topological localization of glycosphingolipid on the cell surface of rat ascites hepatomas.

A simple method for the preparation of oligosaccharide-linked aminohexyl-Sepharose 4B (AH-Sepharose 4B) and its application to the purification of anti-glycosphingolipid antibody which is specific for the oligosaccharide moiety are described. The oligosaccharide, which was obtained from galactosyl(beta 1 leads to 3) N-acetylgalactosaminyl(beta 1 leads to 4)galactosyl(beta 1 leads to 4)glucosylceramide (asialo-GM1) by ozonolysis and subsequent alkali treatment, was covalently linked to the AH-Sepharose 4B by reductamination in the presence of NaBCNH3. Anti-asialo-GM1 antibody was purified by means of an affinity technique with the oligosaccharide-linked AH-Sepharose 4B. The antibody bound to the affinity adsorbent was eluted with 0.5 M NaSCN and 3.0 M NaSCN. Antibody with higher specific activity was recovered in the 3.0 M NaSCN fraction with 50% recovery of the activity of the starting material. The purified antibody was found to be quite specific for asialo-GM1. The presence of asialo-GM1 on the cell surface of free-type rat ascites hepatomas was confirmed by the immunofluorescence technique. The cell aggregates induced by the purified antibody were observed under a scanning electron microscope. The cell connection was found to occur at the tips of microvilli of the surface membrane. The localization of asialo-GM1 on the tips of the surface membrane was confirmed by means of the ferritin-conjugated antibody technique.

Animals↗
PubMed1981

Study of asialogangliosides on surface membranes of rat bone marrow cells and macrophages.

The presence of asialogangliosides on membrane surfaces of rat bone marrow cells and macrophages was studied by an immunological method using anti-glycolipid antibodies with high specificity. The antibodies against N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (GA2), galactosyl(beta 1-3)N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (GA1) and fucosyl(alpha 1-2)galactosyl(beta 1-3)N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (Fuco-GA1) were prepared, and used for cytotoxicity testing and indirect staining by the immunofluorescence technique. In the cytotoxicity test, approximately 40-50% of rat intraperitoneal macrophages were killed by each of the anti-glycolipid antisera. This finding was confirmed by the indirect immunofluorescence staining method with the purified anti-GA2, anti-GA1, and also anti-Fuco-GA1 IgG. When a rat was preimmunized with bovine serum albumin, all macrophages induced in ascites fluid were found to possess GA1 by the staining method. Immature granulocytes were stained specifically with the anti-GA2 antibody. Granulocytes, myelocytes, and megakaryocytes were stained with the anti-GA1 antibody. Blastic myelocytes were stained with the anti-Fuco-GA1 IgG, but lymphocytes were not stained with any of these anti-asialoganglioside antibodies. From these observations, free-type cells such as macrophages and bone marrow cells were found to possess asialogangliosides as membrane components.

Animals↗
PubMed1980

Morphology and histochemistry of large intestinal polyps.

In order to assess the progress of the growth of large intestinal polyps into cancer, the epithelial height and the size of the epithelial nuclei were measured. Mucin histochemistry was also carried out. The increase of the histologic grade was based on the extent of epithelial pseudostratification; epithelial height became greater and epithelial nuclei increased in size. The histochemical mucin values were as follows: the total amount of murin in a given area increased in grade I epithelia in comparison with its behaviour in normal ones, and then decreased gradually with the increase in histologic grade. Neutral mucin became more conspicuous with the increase of epithelial pseudostratification. The amount of sulphated mucin decreased with the increase in histologic grade. In normal epithelia, sialomucin was rarely seen, but in grade I and II epithelia which did not show nuclear stratification the amount of sialomucin increased strikingly. It then decreased in amount with the increase in histologic grade. The noticeable increase of the amount of sialomucin in grade I and II epithelia can be thought of as a temporary pheomenon which appears in an early stage of carcinogenic process. The large intestinal polyps go through several stages before turning into cancer.

Adenocarcinoma↗
PubMed1980

Erythremia with special reference to sideroblastic anemia.

An autopsy case of erythremia with sideroblastic tumor cell proliferation is described. A 60-year-old man was admitted to the hospital due to general fatigue and anorexia. Bone marrow aspiration revealed abnormalities in erythropoiesis (megaloblasts, 4%; sideroblasts, 84%; ring-formed, 39%, and PAS-positive, 5%). Therapy was directed to pulmonary tuberculosis. Anemia was not improved despite repeated whole blood and platelet transfusions. Serum iron and percentage saturation of the total iron-binding capacity rose during the course. Administration of vitamin B12, B6 or folic acid was inefffective. INAH was replaced by its derivative, IHMS, during the course, but the population of sideroblasts especially of ring-sideroblasts was invariably large (78%-100% and 39%-65% for total sideroblasts and ring-sideroblasts, respectively). He died with increasing abdominal pain and jaundice after three months' hospitalization. Main autopsy findings were: diffuse proliferation of atypical erythroblasts in the bone marrow, systemic lymph nodes, liver, spleen and kidneys. Most of the cells positively stained with iron. Tuberculosis of lungs with cavity formation. Discussion is focussed on the relationship between erythremia and sideroblastic anemia.

Anemia, Sideroblastic↗
PubMed1980

Phosphatidylglycerol formation via transphosphatidylation by rat brain extracts.

Phosphatidylglycerol formation by a transfer of the phosphatidyl moiety of phosphatidylcholine to free glycerol was demonstrated in rat brain preparations. Identification of the product as phosphatidylglycerol was accomplished by chromatography, chemical derivatization, and enzymatic hydrolysis. The optimum pH for the reaction was 6.0 with an apparent Km for glycerol of 0.2 M and for phosphatidylcholine of 3.5 mM. Divalent ions were not required and when added caused some inhibition. Phosphatidylcholine was the most effective phosphatidyl donor tested. Similarities to certain properties of phospholipase D also present suggests that these two activities may reside in the same enzyme.

Animals↗
PubMed1980

Surgical treatment of the spontaneous pneumothoraces and its pathological findings.

Open thoracotomies were performed in 124 out of 198 spontaneous pneumothorax episodes from Jan. 1967 to Dec. 1976. By reviewing histological findings of resected specimens, elastofibrosis was remarkable in particular and bullae seem to arise from this elastofibrosis. This change could be irreversible and causes frequent recurrence. So only conservative treatment is not enough and is needed surgical treatment. Regarding operation we prefer bullectomy and/or partial parietal pleurectomy. The latter is useful to reserve pulmonary function and can gain necessary adhesion of the place where frequent bullae formation are observed. And after performing parietal pleurectomy, there is no recurrence.

Adolescent↗
PubMed1979

Partial purification and properties of a rat brain phospholipase.

At least 90% of a membrane-bound phospholipase D was solubilized by extraction of freeze-dried rat brain with 0.8% Miranol H2M and 0.5% cholate. The bulk of base exchange reaction enzymes remained firmly bound to the particulate fraction under these conditions. The phospholipase D specific activity was enriched 240-fold by a purification protocol employing ammonium sulfate precipitation, and both Sepharose 4B and DEAE-cellulose column chromatography. The approximate molecular weight of the partially purified enzyme was calculated to be 200,000 based upon the elution profile from Sepharose 4B and Sephadex G-200 columns. The optimum pH was 6.0, and Km values for phosphatidylcholine and phosphatidylethanolamine were 0.75 mM and 0.91 mM, respectively. The enzyme activity was not dependent on the presence of divalent cation although Ca2+ and Fe2+ showed stimulatory effects.

Animals↗
PubMed1979

Enzymic synthesis of a new type of fucose-containing glycolipid with fucosyltransferase of rat ascites hepatoma cell, AH 7974F.

An alpha-fucosyltransferase activity has been demonstrated in rat ascites hepatoma AH 7974F cells catalyzing the transfer of L-fucose to asialo-GM1 prepared from bovine brain GM1 ganglioside to form a fucolipid in the presence of Triton X-100. The radioactive fucolipid was shown to be Fuc-(alpha1 leads to 2)-Gal-(beta1 leads to 3)-GalNAc-(beta1 leads to 4)-Gal-(beta1 leads to 4)-Glc-ceramide from the following results. The radioactive product coincided with authentic blood group H-active fucolipid from AH 7974F cell on thin-layer chromatography. The product formed a precipitation line not only with Ulex europeus lectin but also with eel anti-H serum on agarose gel plates. The terminal 14C-labeled fucose was released by Bacillus fulminans alpha(1 leads to 2)fucosidase as well as Charonia lampas alpha-fucosidase. The optimum pH value for the incorporation of L-fucose into asialo-GM1 was 5.8 in cacodylate/HCl buffer. The fucosyltransferase was highly specific for asialo-GM1.

Animals↗
PubMed1979

Relation of pancreatic duct hyperplasia to carcinoma.

In order to find a relationship between ductal hyperplasia and carcinoma of the pancreas, histological and histochemical examinations were made on pancreatic specimens of 1,174 autopsy patients with special attention to the age incidence of the former. Ductal hyperplasia was divided into 3 types; nonpapillary, papillary, and atypical hyperplasia. All three types of hyperplasia and ductal carcinoma showed a similar tinctorial property in mucous histochemistry. In general, atypical hyperplasia was seen in the pancreas having papillary hyperplasia which was found in the pancreas associated with nonpapillary hyperplasia. All three types of hyperplasia were apparently more frequent in cancerous pancreases than in non-cancerous ones. They were also more common in the head of the pancreas than in the body and tail. Age incidence also suggests a sequential change from nonpapillary hyperplasia through papillary and atypical ones to carcinoma.

Adolescent↗