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Biomedical subjects

T Matsuda

Publications and source records attributed to T Matsuda.

At least 1,117 records · Page 62Linked to original sources
PubMed1990

Regulation of L-type pyruvate kinase gene expression by dietary fructose in normal and diabetic rats.

Previous studies have shown that dietary fructose stimulates expression of the L-type pyruvate kinase gene mainly at the post-transcriptional level in diabetic liver, and that this effect may be mediated by a metabolite common to both fructose and glycerol. In the present work, we carried out further studies on the mechanism of fructose induction of L-type isozyme mRNA in the liver, kidney and small intestine of rats. The L-type isozyme mRNA in the kidney of normal and diabetic rats was increased by dietary fructose, the time course of the increase being similar to that observed in the small intestine and liver. The mRNA was not induced in the kidney by dietary glucose or insulin. Glycerol was also a potent inducer of the mRNA in the kidney and liver, but not in the small intestine. These results show that fructose and glycerol induced increase in the mRNA only in organs in which they were metabolized, and thus support the metabolite hypothesis. No other carbohydrates tested increased the level of mRNA in these tissues, except glucose, which increased the level in the small intestine. Thus a molecule that increase the mRNA level may accumulate significantly during metabolism of only certain carbohydrates. Dietary fructose or glycerol slightly stimulated transcription of the gene for the L-type isozyme in diabetic liver, and also in normal and diabetic kidney, but the magnitudes of increase were much lower than those of the mRNA, confirming our previous findings described above. On the other hand, dietary fructose caused marked stimulation of gene transcription in normal rat liver, although the magnitude of its induction of the mRNA was similar to that in diabetic liver. Insulin treatment of fructose-fed diabetic rats also caused a marked increase in the gene transcription without any concomitant change in the mRNA level. Thus, the mechanism of fructose induction of the L-type pyruvate kinase in diabetic liver, which is similar to that found in the kidney, is different from that in normal liver, and this difference is attributable to the difference in the level of insulin.

Animals↗
PubMed1990

Purification and characterization of soluble human IL-6 receptor expressed in CHO cells.

An immunosorbent assay system to detect genetically engineered IL-6 receptor (IL-6R) was established, whereby soluble IL-6 receptor (sIL-6R) was detected in the culture medium when sIL-6R cDNA was transfected into COS1 cells. A stably transformed Chinese hamster ovary (CHO) cell line constitutively expressing sIL-6R has been established. The recombinant sIL-6R was purified to homogeneity by sequential filtration and chromatography of the culture medium. The recombinant sIL-6R augmented the sensitivity of M1 cells to IL-6 in growth inhibition assay in a dose-dependent manner. Furthermore, a radioisotope immunosorbent assay (RIA) utilizing recombinant sIL-6R was established which could detect IL-6 in a quantity as low as 10 ng/ml.

Amino Acid Sequence↗
PubMed1990

Regulation of the gene expression of glucokinase and L-type pyruvate kinase in primary cultures of rat hepatocytes by hormones and carbohydrates.

The regulation of the gene expression of two important glycolytic enzymes, glucokinase and L-type pyruvate kinase, by hormones and carbohydrates was studied, in primary cultures of adult rat hepatocytes. Insulin caused time- and dose-dependent increases in the amounts of the mRNAs of the two enzymes in hepatocytes, although glucokinase responded to this hormone faster than L-type pyruvate kinase. The induction of glucokinase mRNA by insulin did not require the presence of glucose itself, but that of the L-type isozyme was dependent on the glucose concentration. For this effect, fructose and glycerol could partially substitute for glucose, but pyruvate and 2-deoxyglucose, a nonmetabolizable glucose analog, could not. The time course of insulin induction in the presence of fructose, but not of glycerol, was similar to that in the presence of glucose. In the presence of glycerol, the mRNA increased in a diphasic manner: the first increase, which probably reflected the effects of fructose and glycerol in normal liver, reached a maximum after 3 h, whereas the second increase corresponded to the increase in the presence of glucose. These results suggested that some metabolite of glucose was required for the insulin-induced increase in L-type pyruvate kinase mRNA. Cycloheximide inhibited the effects of insulin on the two mRNAs, suggesting that ongoing protein synthesis is required in both cases. The addition of 1-(5-isoquinolinesulfonyl)-2-methylpiperazine, an inhibitor of protein kinase C, also inhibited the effects of insulin. However, phorbol 12-myristate 13-acetate alone did not induce the two mRNAs.(ABSTRACT TRUNCATED AT 250 WORDS)

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1990

Congenital bronchobiliary fistula in adults.

Congenital bronchobiliary fistula is a rare malformation. We have presented a case that was diagnosed and treated successfully in an adult. The diagnosis was made by bronchoscopy and bronchography. After excision of the fistula the patient recovered completely. For each patient in whom this anomaly is suspected, bronchoscopy and bronchography are useful for diagnosis.

Adult↗
PubMed1990

A familial factor XIII subunit B deficiency.

A 32-year-old woman with a bleeding tendency born of a consanguineous marriage, was found to have factor XIII subunit B deficiency. An abnormally low level of factor XIII activity was initially noticed and this finding led to further studies of the proband and her family. The notable features were: undetectable subunit B of factor XIII in the proband and her brother and reduced levels of subunit B, 34-52%, in her parents and children. The proband's brother had a markedly decreased level of subunit A protein. The level of factor XIII subunit A in platelets of the proband was normal. The half-life of subunit A determined from the disappearance curve of infused factor XIII subunit A concentrate was approximately 3 d and this is the shortest estimate of the half-life of factor XIII to date. From these results, it is suggested that subunit A is unstable in plasma deficient in subunit B and subunit B stabilizes the A protein. This is the first report of congenital deficiency of factor XIII subunit B and this disorder is thought to be inherited as an autosomal recessive trait.

Adult↗
PubMed1990

Inhibitory effect of aerosol WP871 on SRS-A mediated bronchoconstriction in the guinea pig in vivo.

Slow-reacting substance of anaphylaxis (SRS-A) is an important factor mediating bronchoconstriction in asthma. We developed a guinea pig model for SRS-A mediated bronchoconstriction induced by antigen inhalation. Using this model, we investigated the effect of inhaled WP871, a new anti-allergic drug, on bronchoconstriction. Aerosol WP871 (0.01 and 0.033%) to some extent inhibited the antigen-induced bronchoconstriction in a dose-dependent fashion, but high-dose WP871 (0.1%) inhalation itself produced a non-specific bronchoconstriction. However, aerosol WP871 (0.033%) showed no inhibitory effect on bronchoconstriction caused by direct inhalation of leukotriene C4, a component of SRS-A. These findings indicate that aerosol WP871 does not antagonize SRS-A, but inhibits synthesis and/or release of SRS-A and has some non-specific bronchoconstrictive effect in high concentration.

Aerosols↗
PubMed1990

Monoclonal antibody to blood group glycosyltransferases, produced by hybrids constructed with Epstein-Barr-virus-transformed B lymphocytes from a patient with ABO-incompatible bone marrow transplant and mouse myeloma cells.

A patient with chronic myeloid leukemia secreted an antibody to blood group glycosyltransferases after ABO-incompatible bone marrow transplantation (B recipient/O donor). Peripheral B lymphocytes from the recipient were transformed with Epstein-Barr virus, and then fused by polyethylene glycol with mouse myeloma cell line P3-X63/Ag8.653. After the cloning of the hybridoma cells, a cell line which produced human IgM antibody to blood group glycosyltransferases was established. The antibody completely neutralized B transferase activity at low concentration, while a larger amount of immunoglobulins was required to neutralize A transferase activity.

ABO Blood-Group System↗
PubMed1990

Evidence that pinacidil may promote the opening of ATP-sensitive K+ channels yet inhibit the opening of Ca2(+)-activated K+ channels in K(+)-contracted canine mesenteric artery.

1. The effects of cromakalim and pinacidil on contraction and 86Rb efflux were investigated in strips of canine mesenteric artery. 2. Cromakalim and pinacidil relaxed arterial strips precontracted with 20.9 mM K+ with pD2 values of 6.56 and 5.88, respectively. 3. High (above 10 microM) concentrations of pinacidil, but not cromakalim, relaxed arterial strips bathed by a medium containing 65.9 mM K+, and inhibited Ca2(+)-induced contractions in strips bathed by a medium containing 80 mM K+. These findings suggested that pinacidil may act as an inhibitor of Ca2+ influx. 4. In arterial strips preloaded with 86Rb, cromakalim and pinacidil increased the basal 86Rb efflux. 5. When the effects of cromakalim and pinacidil on 86Rb efflux were determined in arterial strips contracted with 65.9 mM K+, both drugs increased 86Rb efflux. The increase in 86Rb efflux induced by pinacidil was much smaller than that induced by cromakalim. Under the same conditions, nifedipine decreased 86Rb efflux. 6. After the addition of nifedipine to arterial strips contracted with 65.9 mM K+, pinacidil produced a greater increase in 86Rb efflux than in the absence of nifedipine, whereas the effects of cromakalim were the same for the two conditions. Therefore, the effects of pinacidil on 86Rb efflux may be the resultant of two opposing effects: an increased 86Rb efflux due to the opening of ATP-sensitive K+ channels, and a decreased efflux due to the closing of Ca2(+)-activated K+ channels. 7. In causing relaxation, cromakalim was competitively antagonized by glibenclamide with a pA2 value of 7.16. However, glibenclamide antagonism of pinacidil was not of the simple competitive type, suggesting that inhibition of Ca2 + influx may contribute to the relaxant action of pinacidil. 8. It may be concluded that although the ability of pinacidil to increase 86Rb efflux via ATP-sensitive K+ channel opening was similar to that of cromakalim, the inhibition of Ca2 + influx by pinacidil may reduce the opening of Ca2 +-activated K+ channels in K+-contracted arterial strips.

Adenosine Triphosphate↗
PubMed1990

Arthritis in a human T lymphotropic virus type I (HTLV-I) carrier.

The case is described of a 57 year old woman with polyarthritis fulfilling the 1987 revised criteria of the American Rheumatism Association for rheumatoid arthritis, accompanied by clinical carrier state infection of HTLV-I. Anti-HTLV-I IgM antibodies were detected by western blot analysis in her synovial fluid and serum. Atypical lymphocytes with nuclear convolutions were found in synovial fluid and synovial tissue obtained from the affected knee joint, suggesting in situ activation of HTLV-I infected lymphocytes in the affected synovial compartment. The HTLV-I antigens were detected (1.2%) in short term cultured synovial fluid lymphocytes, by indirect immunofluorescence. These findings supported the possibility that HTLV-I has a role in triggering or modifying inflammation in the synovial compartment.

Arthritis, Rheumatoid↗
PubMed1990

Role of D dimer in patients with elevated fibrinogen degradation products in serum: further study in chronic myelogenous leukemia.

We quantitatively assayed the levels of cross-linked fibrin degradation products (D dimer) in plasma at 73 points in time in 32 patients with elevated fibrin/fibrinogen degradation products (FDP) in serum. The assay of FDP was performed on serum samples prepared in test tubes containing 5 U/ml thrombin (final concentration) by a method based on latex agglutination using antifibrinogen antibodies, and the levels of D dimer in plasma were determined by a newly developed latex immunoassay using monoclonal antibodies which do not cross-react with fibrinogen. 5 patients with chronic myelogenous leukemia (CML) had highly elevated FDP levels with normal levels of D dimer. Plasma samples from such patients with CML were treated with various concentrations of thrombin (2-10 U/ml) and after the removal of fibrin clots the levels of FDP in supernatants were assayed by the FDP assay procedure described above. The levels of FDP were normalized when plasma were treated with 10 U/ml thrombin. In 2 patients with CML who had elevated levels of FDP in serum, it was impossible to remove fibrinogen completely by addition of 5 U/ml thrombin. However, FDP levels in the sera treated with 5 U/ml thrombin were almost normal in normal controls and patients with other diseases than CML. From these results it is concluded that residual fibrinogen reacted in the assay procedure as markedly increased FDP in supernatants and elevated FDP levels in serum reflected fibrinogen-related materials, which may not completely polymerize in the presence of lower concentrations of thrombin in some patients with CML. The assay of D dimer in plasma using monoclonal antibodies is recommended in cases of CML to rule out disseminated intravascular coagulation.

Adult↗
PubMed1990

Separation of bovine bronchial epithelial cell subpopulations by density centrifugation: a method to isolate ciliated and nonciliated cell fractions.

Bronchial epithelial cells isolated by protease digestion can be cultured in vitro for the study of proliferation and differentiation. However, these cells represent a heterogenous population, the components of which likely interact with one another. We attempted to utilize density gradient centrifugation as a method to prepare subpopulations of these bronchial epithelial cells. The suspension of the cells obtained by protease digestion of the bovine bronchi was mixed with an equal volume of colloidal silica reagent, Sepracell-MN, and centrifuged to form a continuous density gradient. Two distinct cell layers were identified in addition to a cell pellet at the bottom. Cells from fraction A (top layer) were more than 95% ciliated cells by morphologic examination. These ciliated cells were recovered intact as assessed by trypan blue dye exclusion and by watching beating of their cilia. The cells from fraction C (bottom layer) were 89.9 +/- 3.88% nonciliated, small round cells with a densely staining nucleus and scant cytoplasm. Comparison of cell morphology of these cells with basal cells in vivo and electron microscopic examinations suggested that these cells were basal cells. These basal cells showed an exponential cell proliferation until confluence in Ham's F12 with supplements, LHC9, and a 1:1 mixture of Medium-199 and modified Eagle's medium with 2% fetal calf serum. In contrast, the cells from fraction A grew minimally in all conditions tested. This difference was also shown in the study of DNA synthesis by [3H]thymidine uptake. Enzyme-linked immunosorbent assay for release of bovine fibronectin into cultured media indicated that fraction C cells secreted much more fibronectin (532 +/- 5.28 ng/10(6) cells/h) than fraction A cells (73.4 +/- 1.00). We also used Percoll as a density-gradient reagent and showed potential usefulness in the preparation of cell fractions of bronchial epithelial cells. In conclusion, it was possible to separate ciliated and nonciliated, presumably basal, cells of bovine bronchial epithelial cells. These differed in growth and fibronectin secretion. Studies of airway cell biology may be aided by the availability of more homogenous cell populations.

Animals↗
PubMed1990

Antipurified-protein-derivative antibody in tuberculous pleural effusions.

Using ELISA, we studied anti-PPD antibody values in 31 tuberculous and 39 carcinomatous pleural effusions. Mean ODI values of anti-PPD IgG, IgA and IgM antibodies in tuberculous pleural effusions were higher than those in carcinomatous pleural effusions (p less than 0.01 in IgG and IgA, p less than 0.05 in IgM antibodies). We also analyzed the detected antigens in PPD and BCG whole cell fraction recognized by IgG antibody in tuberculous pleural effusions. Among heteromolecular components, the antigen band from 25 to 40 Kd region was most frequently stained. This antigen was heat-stable, contained sugar components, and included no disulfide bonds.

Adolescent↗
PubMed1990

Effects of aerosol administration of a thromboxane synthetase inhibitor (OKY-046) on bronchial responsiveness to acetylcholine in asthmatic subjects.

Bronchial hyperresponsiveness is one of the major clinical features of bronchial asthma. We previously reported that oral administration of a selective thromboxane synthetase inhibitor, OKY-046, reduced bronchial hyperresponsiveness to acetylcholine in asthmatic subjects. In this study, the effect of aerosol administration of OKY-046 on bronchial hyperresponsiveness was evaluated in ten inpatients with intrinsic asthma. Acetylcholine inhalation tests were performed before and after four days of inhalation of OKY-046 (100 mg/day). The provocative concentration of acetylcholine producing a 20 percent fall in forced expiratory volume in 1 s (PC20-FEV1) and that causing a 35 percent fall in respiratory conductance (PC35-Grs) were measured as indexes of bronchial responsiveness. There was a significant increase in PC20-FEV1 (p less than 0.001) and PC35-Grs (p less than 0.02) after inhalation of OKY-046 from 0.79 (GSEM, 1.41) Mg/ml and 0.96 (GSEM, 1.35) mg/ml to 1.20 (GSEM, 1.41) mg/ml and 1.74 (GSEM, 1.32) mg/ml, respectively. There was no significant difference in forced vital capacity (FVC), FEV1, or respiratory resistance (Rrs) baseline values before and after inhalation of OKY-046. Platelet aggregation was not inhibited by the treatment in other five inpatients. Thus, prophylactic administration of aerosol OKY-046 may be available for treatment of asthma by reduction of bronchial hyperresponsiveness. Further studies are needed to determine the optimum dose.

Acetylcholine↗
PubMed1990

Attenuating effect of a thromboxane synthetase inhibitor (OKY-046) on bronchial responsiveness to methacholine is specific to bronchial asthma.

To determine whether the involvement of thromboxane A2 in bronchial hyperresponsiveness (BHR) is specific to asthma, we examined the effects of a selective inhibitor of thromboxane synthetase (OKY-046) and a cyclooxygenase inhibitor (indomethacin) on bronchial responsiveness to methacholine in normal subjects and patients with chronic bronchitis, diffuse bronchiectasis, and intrinsic bronchial asthma. The provocative concentration of methacholine producing a 20 percent fall in forced expiratory volume in 1 s (PC20-FEV1) was measured before and after oral administration of OKY-046 (2,600 mg over four days) and indomethacin (450 mg over three days) in ten normal, ten bronchitic, nine bronchiectatic, and eight asthmatic subjects, respectively. Baseline values of FEV1 and forced vital capacity (FVC) were not altered by OKY-046 or indomethacin. The geometric mean value of PC20-FEV1 increased significantly (p less than 0.005) from 1.78 to 4.27 mg/ml after OKY-046 in asthmatic subjects, but not in normal, bronchitic, or bronchiectatic subjects. On the other hand, PC20-FEV1 increased significantly (p less than 0.005) from 2.19 to 8.13 mg/ml after indomethacin in bronchiectatic subjects, but not in normal, bronchitic, or asthmatic subjects. We conclude that the involvement of thromboxane A2 in BHR may be specific to asthma, and bronchial responsiveness of bronchiectasis may be potentiated by inflammatory release of bronchoconstrictor prostaglandins except for thromboxane A2. Further studies using thromboxane A2 receptor antagonists are needed to confirm the conclusion.

Acrylates↗
PubMed1990

The postnatal development of the mouse pericardium; the time and mechanism of formation of pericardial pores.

The mouse pericardium is a continuous serous membrane, up to postnatal day 6 (P6), that consists of pericardial and pleural mesothelia with sparse connective tissue sandwiched in between. This study shows that on P7 the pericardium becomes fenestrated, and the pericardial and pleural cavities become continuous. We found that the number of pores per pericardium increased continuously with the advance of age and reached as many as 3000 on P21. Transmission electron microscopy of the pericardium revealed various structures of the pericardial and pleural mesothelia that may relate to the formation of the pericardial pores. The pericardial and pleural mesothelia were adjoined with cytoplasmic processes that extended toward the base of the opposing mesothelium. As a result of the adjoinment, a pair of U-shaped folds were formed. The two U-shaped folds were connected with tight junctions at their apices, and separation of these junctions may give rise to the pericardial pores.

Animals↗
PubMed1990

Mechanistic aspects of cellular interactions with artificial dialyzer membrane surfaces.

The platelet adhesion on adhesive protein-coated surfaces was significantly reduced by the addition of the synthetic tetrapeptide, RGDS (Arg-Gly-Asp-Ser), which was identified as the common amino acid sequence of adhesive site of adhesive proteins. The inhibitory effect was also observed for leukocyte(WBC) in complement-inactivated serum. No significant effect was observed for WBC in complement-activated serum. These indicate that the RGDS ligand-receptor mechanism operates on adhesive protein-adsorbed surfaces for both cellular systems and that activated complement factor (C3b)-membrane receptor (CR3) interaction operates for WBC as the complement is activated.

Amino Acid Sequence↗