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Biomedical subjects

T Kaneda

Publications and source records attributed to T Kaneda.

At least 181 records · Page 10Linked to original sources
PubMed1990

The fine structure of the fibrous zone of articular cartilage in the rat mandibular condyle.

The ultrastructure of the articular fibrous zone of the rat mandibular condyle was observed at 3 and 6 weeks of age in order to investigate the histological changes that occur during the establishment of mastication after suckling. We divided the articular fibrous zone into two layers (F1 layer and F2 layer). The F1 layer was composed of fibroblast-like cells, macrophage-like cells, and the matrix which consisted of granular or fibrillar material, loosely arranged small bundles of collagen fibrils with uniform thickness of 30-50 nm, and independent microfibrils. The F1 layer was continuous with the synovial membrane without any distinct boundary in its peripheral area. Mitotic figures could infrequently be observed in the fibroblast-like cells. The cells in the F2 layer closely resembled fibroblasts. The matrix in the F2 layer mostly consisted of densely arranged bundles of collagen fibrils which are not of uniform diameter ranging 40-100 nm. Elastic fibers occurred among the collagen fibrils. The F1 layer which was observed clearly at 3 weeks almost disappeared at 6 weeks of age. It is confirmed that the F1 layer resembling the synovial membrane exists over the condyle up to the weaning period about 3 weeks of age but it degenerates before 6 weeks of age when the masticatory function is established.

Animals↗
PubMed1990

[Oral aging and loss of teeth].

The human oral mucosa atrophies with aging, and at the same time, loss of teeth occurs and the muscles involved in mastication weaken, leading to masticatory hypofunction. The loss of teeth in animal is serious in that it leads to death. For humans, however, dental prosthesis may aim at functional recovery. From the viewpoint of oral functional recovery, it is important to have a firm grasp of the change in the oral environment with aging. Elderly patients who complain of dry mouth may often have glossodynia, stomatitis, dysgeusia, prosthetic disorder, etc. Although atrophy of the salivary gland is mainly responsible for these disturbances, influences of complications and/or medications cannot be ignored. Secretory immunoglobulin A (sIgA) secretion in the saliva of elderly cases showed a concentration comparable to that of young subjects in their twenties and was considered to be satisfactory from the view-point of oral infection control. On the other hand, plate prosthetic wearers may have high incidence of oral candidiasis, so that in case of loss of teeth, prostheses with so-called implant dentures using artificial dental implants are regarded as physiologically preferable to conventional plate denture.

Adolescent↗
PubMed1990

[Plasma catecholamine response to tracheal intubation after midazolam and vecuronium in elderly patients with hypertension].

This study was undertaken to determine whether midazolam alleviates sympathoadrenal response evoked by tracheal intubation in elderly patients with hypertension. Anesthesia was induced with midazolam in a sleep dose followed by vecuronium 0.1 mg.kg-1. Heart rate and blood pressure were recorded before, 1 and 3 minutes after induction with intubation. Free and total catecholamine (CA) in plasma were measured at each time. Dopamine, norepinephrine and epinephrine (EN) were determined using fluorescence derivatization with diphenylethylenediamine by HPLC. Although heart rate and diastolic pressure rose in some degree 1 min after intubation, free and total CA concentrations did not increase during study period. Free and total EN levels decreased significantly 3 min after intubation. The absence of elevation in plasma CA concentrations, especially in free CA, which is physiologically active, would contribute to produce circulatory stability on laryngoscopy and tracheal intubation. However, the mystery of why hyperdynamic state was produced without the increase in CA concentrations remains to be solved, even though it occurred for a short period of time.

Aged↗
PubMed1990

[Development of ELISPOT assay for thyroid autoantibody-producing cells].

A new assay system for detection of thyroid-autoantibody-producing cells was developed. This assay is based on the ELISPOT method with antigen-coated nitrocellulose membranes in 96-well microfilter plates. This was more sensitive than conventional methods such as a radioimmunoassay and a passive agglutination method for detection of thyroid-autoantibody production. The coefficients of inter- and intra-assay variations for antibody-producing cells were less than 6.5%. Thus, this assay system can be used to analyse the thyroid-specific immunological abnormalities as a routine test.

Agglutination Tests↗
PubMed1989

The effect of dietary autoxidized oils on immunocompetent cells in mice.

Effects of dietary autoxidized oil on immunocompetent cells, such as splenocytes and thymocytes, were studied in mice. When the autoxidized methyl linoleate was administered orally to male C57BL/6 mice in a single dose, the DNA synthesis of thymocytes was remarkably depressed 1 day after the treatment, and then the mitogenic response to concanavalin A of splenocytes was increased 3 days after the dose. With long-term (90 days) feeding of slightly autoxidized soybean oil (with a peroxide value of 150 mequiv/kg) in mice, the DNA synthesis of thymocytes was depressed and the mitogenic response to concanavalin A of splenocytes was increased. No effect was observed on plasma glutamic acid-oxaloacetic acid transaminase and glutamic acid-pyruvic acid transaminase levels, nor on liver thiobarbituric acid reactants due to the dose of autoxidized soybean oil. These findings indicate that oral intake of autoxidized oil affects immunocompetent cells and causes depression of the DNA synthesis of thymocytes in mice.

Animals↗
PubMed1989

Treatment of fetal bovine serum with activated charcoal enhances spontaneous differentiation of murine erythroleukemia cells.

We established a spontaneous differentiation system for murine erythroleukemia cells, MELC-DS19, with high inducibility (80%). The spontaneous differentiation reflected the cells' loss of proliferative capacity. However, this phenomenon was only observed using a subclone, i.e. DS19-sc4, with an inducer-mediated commitment to terminal cell differentiation that was not suppressed by dexamethasone. Essential aspects of the system are the low initial cell density (less than 10(4)/ml) and the use of fetal bovine serum (FBS) treated with activated charcoal instead of ordinary FBS. This system is useful for studying the molecular basis of the spontaneous differentiation of MELC as well as the erythropoiesis regulating factor of sera.

Animals↗
PubMed1989

Peripheral large granular lymphocytes in normal pregnant and postpartum women: decrease in late pregnancy and dynamic change in the puerperium.

Large granular lymphocytes (LGLs) have a variety of cytotoxic activities of NK, K and cytotoxic T lymphocytes, suggesting that their morphology is indicative of lytic function. In non-pregnant normal control women (n = 48), the number of LGLs was 0.30 +/- 0.14 x 10(9)/l and the proportion of LGLs in their peripheral lymphocyte fraction was 14.0 +/- 5.4%. The number and proportion of LGLs were significantly decreased in the third trimester of pregnancy (n = 32; 0.19 +/- 0.08 x 10(9)/l, P less than 0.01, and 11.7 +/- 3.8%, P less than 0.05), although an unexpected increase in the proportion of LGLs was observed in the first trimester of pregnancy (n = 24; 17.5 +/- 6.5%, P less than 0.05). After delivery, the number and proportion of LGLs increased rapidly to restore the non-pregnant levels and showed a marked increase in LGL count 4 months postpartum. These data suggest that lymphocyte-mediated cytotoxicity decreases in late pregnancy and increase dynamically after delivery to restore the non-pregnant state.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1989

Expression of DNA polymerase alpha and Leu3a molecules in growing and saturated cultures of human leukemic cells: phenotype analysis of proliferative cells by flow cytometry.

A flow cytometric method to analyze phenotypes of proliferative cells was developed using human leukemic cell line MOLT 4. A nuclear protein, DNA polymerase alpha (pol alpha), was selected as a marker for proliferative cells, and Leu3a molecule as a cell-surface antigen phenotype marker of the cells. The procedure involved the simultaneous use of fluorescein-conjugated anti-pol alpha antibody, developed by us, and commercially available phycoerythrin-conjugated anti-Leu3a antibody. The optimal fixative for both proteins was phosphate-buffered 2% paraformaldehyde. The pol alpha-positive population in logarythmically growing MOLT 4 cells was estimated, by flow cytometry, to be ca. 95%. A sharp flow cytometry histogram with a strong pol alpha-linked fluorescence was observed. On the other hand, the pol alpha-positive population in the saturated culture was ca. 70%, with weaker pol alpha-linked fluorescence. Thus, the population of pol alpha-positive cells and the amount of pol alpha in cells was dependent on the cell density of the culture. In contrast, ca. 90% Leu3a-positive populations with similar flow cytometry histograms were seen in either growing or saturated states, suggesting that expression of Leu3a was independent of cell density. The flow cytometric method using fluorescein isothiocyanate-conjugated anti-pol alpha antibody is useful for detecting proliferative fractions of free tumor cells, such as leukemic cells. Furthermore, analysis of the phenotype of the proliferative or non-proliferative cells became easier by simultaneous labeling with antibodies against pol alpha and phenotype-specific proteins.

CD4 Antigens↗
PubMed1989

Proliferative cell index in endometrial adenocarcinoma of different nuclear grades.

Proliferative cell indices (PCI) in 20 cases of endometrial adenocarcinoma were obtained by staining DNA polymerase alpha. The PCI ranged from 11.1 to 42.1, averaging 24.7 +/- 8.7. Four cases of stage III all exhibited fairly large PCI (30.4-32.9). In contrast, in 16 cases of stage I the values were spread over a wide range. In 13 cases with histological grade (HG) 1 of stage I, larger PCI were obtained in the nuclear grade (NG) 2 group; the mean PCI values of HG 1-NG 1 and HG 1-NG 2 were 16.5 +/- 4.6 and 25.6 +/- 5.2, respectively. Because of the good correlation between PCI and HG or NG, PCI may be useful as an additional prognostic factor in endometrial adenocarcinoma, especially in stage I cases.

Adenocarcinoma↗
PubMed1989

Gene expression of terminal deoxynucleotidyl transferase in neoplastic cells of leukemia and lymphoma.

Expression levels of terminal deoxynucleotidyl transferase (TdT) mRNA in fresh leukemia and lymphoma cells were measured by northern blotting analysis. Bands of 2.1 kb mRNA were detected in all of eight cases of TdT activity-positive leukemias: two cases of null-cell acute lymphoblastic leukemia (null-ALL), two of common ALL, one of pre-B ALL, one of T-ALL, and two of chronic myelogenous leukemia in blastic crisis. One of the null-ALL and one of the common ALL cases also showed large TdT mRNA (3.3 kb). Since all TdT activity-positive samples exhibited TdT mRNA, the TdT gene might be mainly regulated at the transcription level in leukemic cells. An elevated level of 2.1 kb TdT mRNA was also detected in one lymphoma case, where neither TdT activity nor immunoreactive TdT was detected. The extensive chromosomal abnormality demonstrated in this case might be associated with the translational anomaly of TdT.

Blotting, Northern↗
PubMed1989

A clinicoradiological study of maxillary osteomyelitis.

Eleven cases of maxillary osteomyelitis were studied clinically and radiologically. Clinically, the molar area was most affected. The average age of the patients was 47 years and there was no sex difference. Radiologically, the spotty type of osteolytic change was the most frequent, and osteosclerosis was rare. Sequestrum was not a clear feature radiologically. The features of maxillary and mandibular osteomyelitis were compared and the findings discussed.

Adult↗
PubMed1989

Spontaneous and luminol-dependent chemiluminescences from tissue preparations of benzo[a]pyrene-injected mice.

Chemiluminescence (CL) from tissue preparations of mice i.p. injected with and without the chemical carcinogen benzo[a]pyrene (BP) was detected by a single photon counting apparatus. The spontaneously emitted CL (spontaneous CL) and the CL after luminol addition (luminol-CL) were measured for mice with and without previous induction of their liver mixed-function oxidases (MFO) by phenobarbital. In MFO-non-induced mice, although the spontaneous CL was not notably modified by BP injection, the kidneys presented three times greater luminol-CL after BP injection. On the other hand, MFO-induced mice had higher spontaneous CL of plasma, liver, kidneys, and lungs, as well as higher luminol-CL of liver after BP injection, when compared with the respective MFO-induced but BP-non-injected mice. The luminol-CL of liver was suppressed by scavengers of active oxygen and free-radicals such as TIRON, butylhydroxytoluene and in a less extent by superoxide dismutase. The CL detected from tissue preparations of mice after BP treatment is thought to reflect the formation of oxygen radicals and electronically excited-species during BP metabolism.

1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium ↗
PubMed1989

Marked increase of CD5 + B cells in hyperthyroid Graves' disease.

We examined the proportions of B lymphocytes bearing CD5 cell surface antigen (CD5+ B cells), which are capable of making autoantibodies, in peripheral blood from patients with various thyroid diseases. The level of CD5+ B cells was markedly increased (>9.0%) above the normal range (0.5-7.7%) in untreated, hyperthyroid patients with Graves' disease, although about 10% of the patients had no detectable serum thyroid-stimulating hormone (TSH) receptor antibody (TRAb). However, the levels of CD5+ B cells were normal in untreated patients with destructive thyrotoxicosis due to aggravation of Hashimoto's thyroiditis or subacute thyroiditis. In patients with stimulated hyperthyroid Graves' disease the levels of CD5+ B cells were correlated with those of thyroid hormones and TRAb, all significantly increased. However, once hyperthyroidism was controlled by anti-thyroid drugs, CD5+ B cells were decreased, followed in turn by reduction of TRAb. We conclude that the proportion of CD5+ B cells is useful as a therapeutic index and for diagnosis of Graves' disease and its differentiation from destruction-induced thyrotoxicosis.

Adult↗
PubMed1989

[Clinical studies on TMJ arthrosis in young people. A study of dental axis of lower molar teeth].

The subjects were 37 female patients with juvenile TMJ arthrosis (T group) and 27 healthy females (N group) who visited the Dept. of Oral Surgery, Nagoya University Hospital or the Dept. of Dent-Oral Surgery, Nagoya University Branch Hospital. Following evaluations were made: 1) L6 to L7 angle 2) L6 to occlusal plane 3) L7 to occlusal plane 4) L6 to mandibular plane 5) L7 to mandibular plane 6) occlusal plane angle 7) mandibular plane angle Following results were obtained: 1. Significant differences between T group and N group were not seen in the occlusal plane angle. 2. A majority in the T group showed a mesial inclination of the lower second molar. 3. Mandibular plane angle in the T group was larger than that in the N group.

Adolescent↗
PubMed1988

Biosynthesis of branched-chain fatty acids in Bacillus subtilis. A decarboxylase is essential for branched-chain fatty acid synthetase.

Branched long-chain fatty acids of the iso and anteiso series are synthesized in many bacteria from the branched-chain alpha-keto acids of valine, leucine, and isoleucine after their decarboxylation followed by chain elongation. Two distinct branched-chain alpha-keto acid (BCKA) and pyruvate decarboxylases, which are considered to be responsible for primer synthesis, were detected in, and purified in homogenous form from Bacillus subtilis 168 strain by procedures including ammonium sulfate fractionation and chromatography on ion exchange, reversed-phase, and gel absorption columns. The chemical and catalytic properties of the two decarboxylases were studied in detail. The removal of BCKA decarboxylase, using chromatographic fractionation, from the fatty acid synthetase significantly reduced its activity. The synthetase activity was completely lost upon immunoprecipitation of the decarboxylase. The removal of pyruvate decarboxylase by the above two methods, however, did not affect any activity of the fatty acid synthetase. Thus, BCKA decarboxylase, but not pyruvate decarboxylase, is essential for the synthesis of branched-chain fatty acids. The very high affinity of BCKA decarboxylase toward branched-chain alpha-keto acids is responsible for its function in fatty acid synthesis.

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

Characterization of fluorescent products from reaction of methyl linoleate hydroperoxides with adenine in the presence of Fe2+ and ascorbic acid.

The structures of fluorescent products formed in the reaction of methyl linoleate hydroperoxides with adenine, FeSO4 and ascorbic acid were investigated to elucidate the mechanism of interaction. The fluorescent products consisted of at least four major components (I-IV), which could be separated by thin-layer chromatography and high-performance liquid chromatography. Both 2-octenal and 2,4-decadienal, degradation products of methyl linoleate hydroperoxides, reacted with adenine to produce a fluorescent product similar to one of the major compounds (II) formed in the reaction of methyl linoleate hydroperoxides. Spectroscopic data suggest that I and III are the same type of compounds, which have closed ring structures with alpha, beta-unsaturated carbonyl groups between the amino group at the 6-position and the nitrogen at the 1-position of adenine. Component II has a closed ring structure at the same site as I and III, and the presence of an ether linkage was suggested. On the basis of these structures, the involvement of 3-nonenal, methyl 12-oxo-9-dodecenoate and 2-octenal was suggested in the interaction of the methyl linoleate hydroperoxides decomposition products and adenine or DNA in the presence of FeSO4 and ascorbic acid.

Adenine↗
PubMed1988

Purification and properties of 4-hydroxycyclohexanecarboxylate dehydrogenase from Corynebacterium cyclohexanicum.

4-Hydroxycyclohexanecarboxylate dehydrogenase, which requires NAD as a cofactor, was detected in crude soluble extracts of Corynebacterium cyclohexanicum grown on cyclohexanecarboxylic acid as the sole carbon source. The dehydrogenase was purified from extracts to an electrophoretically homogenous state by ammonium sulfate precipitation and chromatography on DEAE-650s, agarose-NAD and hydroxyapatite. The enzyme consisted of two identical subunits and had a native relative molecular mass of 53,600. There were two residues each of cysteine and tryptophan in the enzyme molecule. Oxo acid rather than hydroxy acid was routinely used as substrate for assay of the enzyme. The enzyme is highly specific for 4-oxocyclohexanecarboxylic acid: the carboxyl group is essential and the position of carbonyl group is important; neither the 2-oxo nor the 3-oxo homologue was used as substrate. A methyl substitution on the ring of 4-oxocyclohexanecarboxylate resulted in an almost complete loss of its activity. The reduction product was identified as trans-4-hydroxycyclohexanecarboxylic acid by gas-liquid chromatography and mass spectrometry. It was used as a substrate for the reverse reaction in the presence of NAD but not its cis-isomer. The enzyme was specific for the B-side (pro-S) hydrogen of NADH in the hydrogen transfer from NADH to 4-oxocyclohexanecarboxylate. The Km values for 4-oxocyclohexanecarboxylate and NADH in the reduction reaction at pH 6.8 were 0.50 mM and 0.28 mM, respectively, whereas those for trans-4-hydroxycyclohexanecarboxylate and NAD in the oxidation reaction at pH 8.8 were 0.51 mM and 0.23 mM, respectively. The equilibrium constant of the reaction was 1.79 x 10(-10) M. The enzyme was strongly inhibited by N-bromosuccinimide.

Alcohol Oxidoreductases↗