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T Kaneda

Publications and source records attributed to T Kaneda.

At least 199 records · Page 11Linked to original sources
PubMed1988

The effect of dietary lipid hydroperoxide on lymphoid tissues in mice.

Effects of dietary lipid hydroperoxides on lymphoid tissue were studied in mice. When graded amounts (190, 270 and 310 mg) of methyl linoleate hydroperoxide (MLHPO) were orally administered to male C57BL/6 mice (6 weeks old), necrosis was observed in lymphocytes located among the reticular network in the thymus, and thymus weight was significantly decreased 24 h after the treatment. The spleen weight of mice given MLHPO tended to decrease. Spontaneous chemiluminescence of the thymus was remarkably increased after the dose. Thiobarbituric acid reactants in the liver, thymus and blood were also increased after the dose of MLHPO. At intervals of 3, 6, 12 and 24 h after a dose of 14C-labeled MLHPO, 14C was detected in the blood and liver. Fatty infiltration of the liver was found after the treatment with MLHPO. These findings indicate that oral intake of lipid hydroperoxides causes significant damage to lymphoid tissues of mice.

Administration, Oral↗
PubMed1988

Stereoselectivity in the 2-methylbutyrate incorporation into anteiso fatty acids in Bacillus subtilis mutants.

Two Bacillus subtilis mutants defective in branched-chain alpha-ketoacid dehydrogenase can grow when 2-methylbutyrate is provided in trypticase soy medium. Both enantiomers of the acid supported growth of the mutants but the (S)-(+)-isomer (natural) was more active than the (R)-(-)-isomer (unnatural). The mutants utilized these isomers as primer to specifically synthesize either enantiomer of anteiso fatty acids. No racemization of the isomer primers was observed during the synthesis. Thus, cells grown with (-)-isomer possessed anteiso fatty acids (over 80%) of the total fatty acids, being entirely the unnatural enantiomer. The stereospecific synthesis was found to be controlled at the step of 2-methylbutyryl-CoA synthesis. In a wild strain, only (+)-specific acyl-CoA synthetase was detected. In the mutants, either enantiomer of 2-methylbutyrate could simultaneously induce both types, (+)-specific and (-)-specific, of acyl-CoA synthetase. (+)-Specific synthetase had a higher activity and affinity towards substrate than (-)-specific synthetase. The detailed preparative procedures for (R)-(-)- and 2-[3,4-3H]methylbutyric acid are described.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed1988

Detection of proliferative cells in dysplasia, carcinoma in situ, and invasive carcinoma of the uterine cervix by monoclonal antibody against DNA polymerase alpha.

The distribution of DNA polymerase alpha-positive cells in neoplasia of the uterine cervix and in normal cervical epithelium was studied using a monoclonal antibody against DNA polymerase alpha. The positive cells were found only in the parabasal layer of normal cervical epithelium and only in the nonkeratinized areas of the cancer nests of invasive keratinizing carcinoma. Most cells in cancer nests of an invasive nonkeratinizing carcinoma were found to be DNA polymerase alpha-positive. In cases of mild or moderate dysplasia DNA polymerase alpha-positive cells were found only in the lower half of the epithelium. DNA polymerase alpha-positive cells in severe dysplasia to carcinoma in situ were distributed throughout the full thickness of the epithelium. The percentages of DNA polymerase alpha-positive cells in mild or moderate dysplasia, severe dysplasia to carcinoma in situ, and invasive carcinoma were 32.2%, 45.7%, and 53.7%, respectively. The authors previously developed immunohistochemical methods for detecting DNA polymerase alpha by monoclonal antibody that allowed the proliferative activity of cells in normal and neoplastic tissues to be estimated.

Antibodies, Monoclonal↗
PubMed1988

Presence of phosphatidylcholine hydroperoxide in human plasma.

A chemiluminescence-high performance liquid chromatography (CL-HPLC) system was newly developed and used for the hydroperoxide-specific determination of phosphatidylcholine hydroperoxide (PCOOH) in human plasma. The method involves separation of phosphatidylcholine derivatives from plasma lipids by normal phase HPLC and subsequent detection of hydroperoxide-dependent chemiluminescence (CL) of PCOOH. CL was produced through luminol oxidation during the reaction of the hydroperoxide and cytochrome c-heme. The high specificity for the hydroperoxide allows the sensitive assaying of a large PCOOH range over a concentration range of 50-2,000 pmol of hydroperoxide-O2. Using this method, the occurrence of PCOOH in normal human plasma was strongly suggested and was confirmed quantitatively.

Calibration↗
PubMed1988

Chronotropic effect of nizofenone fumarate in rabbit sino-atrial node in vitro.

1. The effects of nizofenone fumarate were studied on the membrane potentials and currents of rabbit sino-atrial node preparations by means of the double-microelectrode voltage clamp method. 2. In spontaneously firing pacemaker cells, nizofenone (above 1 microM) decreased the heart rate. Above 3 microM, nizofenone reduced the maximum upstroke velocity, the amplitude of the action potential and the slope of the phase 4 depolarization, and prolonged the action potential duration at 50% repolarization. 3. Under voltage clamp conditions, nizofenone decreased the slow inward current and the time-dependent potassium outward current in a dose-dependent manner. 4. These findings suggest that nizofenone exerts an inhibitory action on the automaticity of sinoatrial node preparations via effects on both inward and outward currents.

Action Potentials↗
PubMed1988

Transplantation of mucosal tissue model composed of rabbit oral mucosal cells.

Since skin grafted into the oral cavity does not differentiate into mucosa, its original characteristics remain unchanged. This may cause discomfort to patients treated with such grafted skin, due to the skin's hair follicles and keratinization. This phenomenon is controlled by subepithelial connective tissues, and is thus referred to as the Epithelio-Mesenchymal Interaction. The grafting of mucosa itself would be preferable, but this procedure is severely limited due to the scarcity of suitable tissue. Accordingly, we have recently prepared artificial mucosa in vitro, using fibroblasts and epithelial cells derived from rabbit oral mucosa and collagen gel, and transplanted it into a donor animal. This paper is the first report of a method using artificial mucosa for the reconstruction of mucosal defects.

Animals↗
PubMed1988

Immunohistochemical analysis of cells in mucosal lesions of oral lichen planus.

We immunohistochemically analyzed the immunological background of the pathogenesis of oral lichen planus (OLP). Abundant lymphocytes infiltrated OLP mucosal lesions, particularly in satellite cell necrosis (SCN) regions, and cytotoxic/suppressor T lymphocytes were predominant in seven of 10 OLP cases. Some carried IL-2 receptors, particularly in SCN. Keratinocytes of the mucosal lesions expressed both HLA-ABC and HLA-DR antigens. This suggests that activated cytotoxic/suppressor T lymphocytes may play a major role in cytotoxicity to keratinocytes as effector cells in OLP. OKM1-, OKM5+, HLA-DR+ and IL-1+ cells, vascular endothelial cells and clusters of spindle-shaped or oval cells, which had the same surface characteristics as a monocyte macrophage subset, were abundant and, together with migrating lymphocytes, might play a role in the immune response in mucosal lesions of OLP.

Adult↗
PubMed1988

Immunoelectron microscopical localization of immunoglobulins, secretory component and J chain in the human minor salivary glands.

Localization of IgA, secretory component (SC) and J chain was investigated immunocytochemically in minor salivary glands of the lip and palate to define the mechanism involved in the transport of immunoglobulin A (sIgA) into the saliva from the minor salivary glands. SC synthesis was detected in mucous acinar cells and ductal epithelial cells. Free SC is secreted into the saliva through secretory granules in the mucous acinar cells. Dimeric IgA containing J chain is translocated through these cells as sIgA by a SC-mediated transport mechanism involving cytoplasmic vesicles.

Cell Membrane↗
PubMed1988

Activated charcoal diminishes the lot difference of fetal bovine sera in erythroid colony formation of human bone marrow cells.

Using normal bone marrow as target cells, we assayed the colony-forming efficiency of early and late erythroid progenitor cells and granulocyte-macrophage progenitor cells using several different lots of fetal bovine serum (FBS). There was a marked difference in the ability of these sera to support colony formation, particularly in erythroid colony assays. When adsorbed by activated charcoal, all these sera supported erythroid colony formation more efficiently than before adsorption. There was no significant effect of charcoal adsorption of FBS on granulocyte-macrophage colony formation. Gel-filtration study showed that charcoal adsorption diminished low-molecular-weight fractions by less than 5000 Da. The inhibitory activity of this fraction was heat labile and Pronase sensitive. Concentrated samples obtained from these fractions inhibited erythroid colony formation in a dose-dependent manner. These results suggest that low-molecular-weight inhibitors that are relatively specific to erythropoiesis play a critical role in the lot differences of FBS for erythroid colony formation.

Adsorption↗
PubMed1988

DDAVP and epinephrine-induced changes in the localization of von Willebrand factor antigen in endothelial cells of human oral mucosa.

A peroxidase-labeled antibody technique revealed von Willebrand factor antigen (vWF:Ag) in rough endoplasmic reticulum (rER), the perinuclear region, and the cytoplasmic vesicles of capillary endothelial cells in oral mucosa. After administration of epinephrine or 1-deamino-8-D-arginine vasopressin (DDAVP), the localization of vWF:Ag was shown to have changed to the basement membrane and the surrounding interstitium. This change of vWF:Ag localization induced by epinephrine and DDAVP may play a role in the adhesion of platelets to subendothelium following endothelial injury during surgery and may be an unknown hemostatic effect of these drugs.

Adult↗
PubMed1987

Analysis of human terminal deoxynucleotidyl transferase cDNA expressible in mammalian cells.

Human Molt3 cDNA library was constructed using pcD vector system which permits the expression of cDNA inserts in mammalian cells. Nearly full-length human terminal deoxynucleotidyltransferase (TdT) cDNA was cloned using a fragment of bovine TdT cDNA as a probe. The human TdT cDNA contains an open reading frame of 1,557 bp coding for 519 amino acids, including 31 bp and 341 bp from 5' and 3' untranslated regions, respectively. The TdT cDNA was transfected into COS7 monkey fibroblasts directed the synthesis of enzymatically active protein of Mr 59,495. The cloned TdT cDNA hybridized with poly A+ RNAs of 2,100 b and 3,300 b from stable T-cell leukemia Molt3 and Molt4 cells.

Animals↗