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Biomedical subjects

M Katayama

Publications and source records attributed to M Katayama.

At least 127 records · Page 7Linked to original sources
PubMed1995

ABO blood group genotype and plasma von Willebrand factor in normal individuals.

von Willebrand factor (vWF) is a multimeric plasma protein with ABO (H) blood group sugar chains. We investigated a total of 330 plasmas from normal individuals having various ABO genotypes, with special reference to vWF antigen and its platelet glycoprotein-Ib-related biological activities, termed ristocetin cofactor (RCof) and botrocetin cofactor (BCof). RCof reflects the biological activity of higher vWF multimers, while BCof reflects that of vWF of multimers of all sizes. Plasmas from normal individuals carrying one O gene (genotypes AO and BO) had slightly, but proportionally lower levels of vWF antigen, RCof, and BCof than those carrying no O gene (genotypes AA, AB, and BB). Normal plasmas from individuals carrying two O genes (genotype OO) showed much lower values for these parameters than the other plasmas, as previously reported. However, multimeric analysis of plasma vWF antigen revealed no differences among the different genotypes.

ABO Blood-Group System↗
PubMed1995

Molecular cloning of the cyanobacterial adenylate cyclase gene from the filamentous cyanobacterium Anabaena cylindrica.

Molecular cloning of the structural gene for adenylate cyclase (cya) of the cyanobacterium Anabaena cylindrica was carried out by complementation of an Escherichia coli strain defective in the cya gene. The cya-defective strain produced significant amounts of cyclic AMP when it was transformed with the cya gene isolated from A. cylindrica. This gene encodes a polypeptide consisting of 502 amino acid residues (molecular weight, 55,300). The deduced primary protein structure showed that the carboxyl-terminal region of the adenylate cyclase of A. cylindrica shows strong structural similarity to the conserved regions of the adenylate cyclases of various eukaryotes. No similarity was found between the amino acid sequences of the cya gene of A. cylindrica and that of E. coli. A hydropathy plot suggests that this protein has two hydrophobic regions, a transmembrane span and a signal peptide. An antiserum specific to this adenylate cyclase was prepared by immunizing a rabbit with a glutathione S-transferase-adenylate cyclase fusion protein expressed in E. coli. This antiserum recognized a 55-kDa protein in Anabaena cell lysates. Subcellular fractionation analysis showed that A. cylindrica adenylate cyclase localized in the thylakoid membrane.

Adenylyl Cyclases↗
PubMed1995

Effect of indomethacin on lung development in postnatal rats: possible role of prostaglandin in alveolar formation.

We administered 1.3 mg ip of indomethacin, a prostaglandin synthetase inhibitor, per 100 g body wt to male rat pups daily on postnatal days 4-13 and examined their lungs on day 14. Indomethacin administration produced abnormal lung structure with diminished alveolar air, increased alveolar duct air, increased mean linear intercept (gas-exchanging wall distance), diminished gas-exchanging surface area and surface-to-volume ratio, increased septal wall thickness, diminished the number of alveolar crests, and increased the number of lamellar bodies in alveolar type II cells. However, this procedure did not alter quantitative lung growth (normal lung weights, volumes, and DNA and protein contents). Tissue prostaglandin content was decreased. The total amount of lung collagen or elastin was unchanged, but when collagen was analyzed into soluble and insoluble components, soluble collagen was increased. Supplementation with 1.0 g of prostaglandin E2 per 100 g body wt to animals treated with indomethacin reduced the abnormalities in pulmonary architecture. We conclude that indomethacin affects lung structure in growing rats and that it is an unusual model in that lung growth is normal, but lung development is abnormal. We also suggest that prostaglandins may play a significant role in alveolar formation in postnatal lung development in rats.

Animals↗
PubMed1995

Effect of hypoxia on intracellular pH of glomus cells cultured from cat and rat carotid bodies.

To test the hypothesis that hypoxia may induce cellular acidification during chemotransduction in the carotid body, we compared the effects of hypoxia and of extracellular acidosis on intracellular pH (pHi) of glomus cells cultured from rat and cat carotid bodies. The cells were prepared and cultured for 2-7 days. The plated cells were loaded with a pH-sensitive fluorescent probe, SNARF-1-acetoxymethyl ester, and were placed in a closed chamber and superfused. The effects of lowering PO2 and pH in the superfusion medium containing CO2-HCO3- buffer on the glomus cell pHi were measured at 37 degrees C. The pHi was measured in a single or a few isolated cells with single excitation at 540 nm and dual emission at 590 and 640 nm, after the exposure to different PO2 levels from 132 to 43, 14, and 1-2 Torr for 10-12 min in the closed chamber. The resting pHi values were 7.263 +/- 0.008 for rat and 7.175 +/- 0.004 for cat carotid body glomus cells. For a decrease of PO2 from 132 Torr to 14 Torr, the change in pHi values, on average, for cat and rat glomus cells was 0.034 lower, and with PO2 decrease to 1-2 Torr for the cat glomus cells, the change in pHi values was 0.051 lower. On the other hand, when the perfusate pH values were decreased from 7.4 to 6.9 during normoxia, the reduction of change in pHi values were 0.327 for the rat and 0.397 for the cat. Thus glomus cell pHi change due to low PO2 exposure was not significant and was not commensurate with the large increases in the chemosensory activity.

Acidosis, Lactic↗
PubMed1995

Inhibition of endothelial nitric oxide synthase activity by protein kinase C.

Nitric oxide (NO) is an important molecular messenger accounting for endothelium-derived relaxing factor. Recently, NO synthase (NOS) from cultured endothelial cells has been purified and molecularly cloned. To evaluate the effect of phosphorylation by protein kinase C (PKC) and cyclic AMP-dependent protein kinase (PKA) on endothelial constitutive NOS catalytic activity, we incubated purified endothelial NOS with PKC or PKA. Endothelial NOS was stoichiometrically phosphorylated by PKC and PKA. In intact bovine aortic endothelial cells (BAECs), NOS was phosphorylated by stimulation with 12-O-tetradecanoylphorbol-13-acetate (TPA). NOS activity measured by the conversion of [3H]arginine to [3H]citrulline in homogenates of BAECs treated with TPA or phorbol 12,13-dibutyrate was reduced by 30%, whereas dibutylyl cyclic AMP did not affect NOS activity. Moreover, we measured NO release from cultured BAECs by a chemiluminescence method to examine the effect of PKC and PKA on endothelial NOS activity. In cultured BAECs, ATP gamma S and A23187 induced NO release in time- and dose-dependent manners. Phorbol esters such as TPA and phorbol 12,13-dibutyrate dose dependently inhibited NO release stimulated by A23187 as well as ATP gamma S. Reduction of NO release by TPA was almost completely prevented by pretreatment with staurosporine, an inhibitor of PKC. NO release by A23187 was increased in PKC-downregulated BAECs. In contrast, dibutylyl cyclic AMP or 8-bromo cyclic GMP had no effect on NO release from BAECs induced by A23187 or ATP gamma S. These results indicate that phosphorylation of NOS by PKC is associated with a reduction of its catalytic activity in vascular endothelial cells.

Amino Acid Oxidoreductases↗
PubMed1995

Soluble form of P-selectin in plasma is elevated in acute lung injury.

A number of adhesion molecules on neutrophils and the pulmonary capillary endothelium mediate the neutrophil accumulation in the lungs at the onset of adult respiratory distress syndrome or acute lung injury (ALI). P-selectin, located on both vascular endothelial cells and platelets, has been shown to be one of these neutrophil-endothelial cell adhesion molecules. In this study, we measured the soluble form of P-selectin in plasma (PPS) from 19 patients (surviving, 11; deceased, 8) with ALI due to various causes and assessed the clinical significance of this measurement. Twelve healthy subjects and 29 patients with other pulmonary diseases, including idiopathic pulmonary fibrosis (IPF) (n = 8), sarcoidosis (n = 5), pneumonia (n = 8), and sepsis without ALI (n = 8) were also studied for comparison. PPS in patients with ALI (474.5 +/- 366.8 ng/ml, mean +/- SD) were significantly higher than those in control subjects (98.8 +/- 39.7, p < 0.01) and in patients with IPF (210.4 +/- 76.6, p < 0.05), sarcoidosis (135.2 +/- 71.5, p < 0.05), pneumonia (225.3 +/- 81.0, p < 0.05), and sepsis without ALI (271.8 +/- 46.5, p < 0.05). There was no significant difference in PPS levels between seven patients with and 12 patients without multiple organ failure. Lung injury scores correlated significantly with the PPS level (r = 0.605, p < 0.05). PPS levels of deceased patients with ALI (841.0 +/- 252.4) were significantly higher than those of surviving patients with ALI (208.0 +/- 109.2, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Comparison of therapeutic efficacies of type A and F botulinum toxins for blepharospasm: a double-blind, controlled study.

Type F botulinum toxin can be used for treating patients with dystonia who become refractory to type A toxin injection due to antibody development. We compared the therapeutic efficacy of type F botulinum toxin to that of type A toxin in a self-controlled, double-blind clinical trial. In nine patients with blepharospasm, we injected type A toxin on one side and the same units of type F toxin on the other side. Although the onset of clinical effect, maximal benefit, and adverse reactions were similar between type A and F toxins, the duration of the clinical effect was significantly shorter on the side injected with type F toxin. Although type F toxin proved its promise as an alternative to type A toxin, its usefulness is limited by the shorter duration of action.

Aged↗
PubMed1995

Optical resolution of 1-arylethanols with a condensed aromatic ring by lipase from Pseudomonas aeruginosa.

Enantioselective syntheses of both enantiomers of 1-arylethanols with a condensed aromatic ring have been done through acetylation of the racemic alcohols with vinyl acetate in the presence of a lipase from Pseudomonas aeruginosa (Toyobo, LIP). The lipase LIP showed high enantioselectivity and reactivity for the title compounds, reacted acetates, and remaining alcohols were obtained with high optical purity.

Acetylation↗
PubMed1995

[The differences between individualists and cooperators: interpersonal cognition of resource allocation].

The purpose of this article is to study interpersonal cognition of resource allocation and individual differences in the cognition. Sixty subjects participated in an experimental game, and 18 individualists and 16 cooperators were selected according to their tendency in resource allocation, which is called social values. Then, they rated resource allocating behavior. Major findings were as follows: (1) Both groups rated "allocating more resource to the partner" as more socially desirable and friendly. (2) Individualists rated "allocating more resource to self," which was consistent with their social values, as more socially desirable. They also rated "equal allocation with own resource adjusted" as more socially desirable but less dynamic. (3) Cooperators rated "equal allocation with own resource adjusted," which was consistent with their social values, as more socially desirable and friendly. (4) Both groups rated "more resource to self" and "less resource to the partner" as dynamic (active and assertive). The relation between interpersonal cognition and social values is discussed.

Adult↗
PubMed1995

Characterization of neurotrophic factors produced by immortalized mouse brain glial cells (VR-2g).

We analyzed the neurotrophic factors secreted by immortalized fetal mouse brain glial cells (VR-2g). Concentrated conditioned medium of VR-2g cells were applied to a gel filtration column and the trophic activities of the fractions were determined by the bioassay method with primary fetal rat striatal neurons. Several peaks of neurotrophic activity were detected, the most prominent of which was found in a fraction of molecular weight 5-7 kDa. In peak fractions of molecular weight 13-26 kDa, molecules reactive to anti-NGF antibodies were detected by Western blotting only in non-reduced condition of SDS-PAGE. Anti-NGF antibodies absorbed 40% of the neurotrophic activities in the conditioned medium of VR-2g cells.

Animals↗
PubMed1995

[A case of mixed connective tissue disease associated with gastric cancer and cancer of the uterine cervix].

We report here a very rare case of MCTD complicating double cancer. A 43-year-old woman with suspected MCTD was admitted because of high fever and lymphadenopathy. The laboratory findings indicated high titers of speckled ANA, anti-RNP, DNA and Scl-70, but anti-Sm. SS-A and SS-B was not detected. Chest CT and Spirogram revealed lung fibrosis, restrictive ventilatory impairment, and decreased diffusion capacity. Biopsy specimen by gastric fiberscope s screening indicated II c advanced type of poorly differentiated adenocarcinoma. After subtotal gastrectomy, she had high fever, pleuritis, leukopenia, butterfly erythema and hypoxemia, which were improved by 30 mg/day of oral prednisolone. One year after from the last operation, she had contact bleeding, and squamous cell carcinoma of the uterine cervix was diagnosed. She had Raynaud's phenomenon 6 months after from hysterectomy.

Adenocarcinoma↗
PubMed1995

[Muscle afferent block for the treatment of writer's cramp].

A 29-year-old man suffered from dystonic writer's cramp for over three years. When he wrote, typed and did other tasks using right hand, dystonic involuntary movement triggered medial rotation of the arm, wrist extension and shoulder elevation. Medication, biofeedback, and botulinum injection were performed without much success. We tried to block the sensory input from muscles by using lidocaine and ethanol. We made injections of 0.5% lidocaine 50ml and 99% ethanol 5ml into muscles with abnormal activity at the frequency of twice a week for about six months. After the treatment, dystonic movement was remarkably improved and he was then able to write, type and perform other tasks with the right hand. Side effects included pain of the injection site, nausea and dizziness, which lasted for a few hours. This "muscle afferent block" did not cause muscle weakness. We speculate that muscle afferent plays a pivotal role in dystonia so that its blocking may be of clinical use.

Adult↗
PubMed1995

Effects of bifemelane hydrochloride on plasma neuropeptide Y, 3-methoxy-4-hydroxyphenylethylene glycol and 5-hydroxy-indole acetic acid concentrations in patients with cerebral infarction.

Bifemelane hydrochloride (BH) is widely employed in Japan in the treatment of cerebral infarction patients with depressive symptoms and its antidepressant action is considered to be caused by the normalizing effects of neurotransmitters. The relationship between the normalizing effects of neurotransmitters of BH and the depressive state of patients with cerebral infarction was examined. BH 150 mg/day was administered for three months to 13 cerebral infarction patients with depressive state. We measured the plasma neuropeptide Y (NPY), 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) and 5-hydroxy-indole acetic acid (5-HIAA), and assessed the depressive symptoms using the 21-item Hamilton's Rating Scale for Depression (HRSD) before and after administration of BH. After treatment, the plasma NPY concentration was significantly increased, the plasma MHPG concentration and total score of HRSD were significantly decreased, and the plasma 5-HIAA concentration showed no changes. These findings suggest that the antidepressant effect of BH is caused by the normalizing effects of NPY and noradrenalinergic neurons.

Aged↗
PubMed1994

Immunoenzymometric analysis for expression and shedding of intercellular adhesion molecule-1 on human endothelial cells stimulated with cytokines or lipopolysaccharide.

Unstimulated endothelial cell (EC) cultures express low levels of intercellular adhesion molecule-1 (ICAM-1) and their expression can be enhanced by inflammatory cytokines such as tumor necrosis factor alpha (TNF). Three monoclonal antibodies (MoAbs) highly reactive with TNF-stimulated human ECs were established and defined to recognize a 95 kDa cell surface protein specifically expressed on cytokine-activated ECs, which was immunochemically identified as ICAM-1. The quantitative immunoassay of soluble and insoluble ICAM-1 could be performed with two different MoAbs. Secretion of fibronectin or the von Willebrand factor, was not significantly enhanced with TNF stimulation. Cellular expression of ICAM-1 was drastically induced by TNF or interleukin-1 stimulation, and the moderate expression with delayed-action was observed only by lipopolysaccharide stimulation. A maximal amount of soluble ICAM-1 was released from ECs stimulated only by TNF, apparently in a dose dependent manner, but no significant release of ICAM-1 was induced by thrombin interleukin-2, or lipopolysaccharides. Released levels of soluble ICAM-1 from interleukin-1-stimulated ECs were apparently diminished as compared with those from TNF-stimulated cells. These results suggest that release of soluble ICAM-1 from EC surfaces can be most significantly enhanced by TNF-specific signaling, and prospectively, should be a sensitive indicator of intravascular inflammation in acute endothelium injury.

Antibodies, Monoclonal↗
PubMed1994

Alternatively spliced isoform of P-selectin is present in vivo as a soluble molecule.

To demonstrate the presence of a soluble isoform of P-selectin predicted from cDNA sequencing (Johnston, G.I., Bliss, G.A., Newman, P.J., and McEver, R.P. (1990) J. Biol. Chem. 265, 21381-21385), we immunoisolated and compared structurally P-selectin from fresh frozen human plasma with that from washed intact platelets. Plasma P-selectin was reactive with rabbit antiserum to a synthesized peptide (residues 762-774 of mature P-selectin) but was significantly less reactive with antibody to a peptide (residues 747-760). In contrast, platelet P-selectin reacted with both antibodies. S-Pyridylethylated plasma P-selectin was fractionated by reversed phase-high performance liquid chromatography into two major species. From platelets, two virtually identical species were separated. Sequential digestion with Achromobacter protease I and then Staphylococcus V8 protease produced peptides assigned to the tail region of the protein including the putative spliced site. From the more hydrophilic species in both plasma and platelets, a peptide completely lacking the sequence of the putative spliced site was identified. In contrast, the more hydrophobic species yielded a peptide with an intact transmembrane sequence. Hence, these results provide direct evidence that the previously predicted soluble isoform of P-selectin is actually synthesized in vivo and is present as a circulating molecule.

Alternative Splicing↗