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Biomedical subjects

R Matsuura

Publications and source records attributed to R Matsuura.

At least 19 recordsLinked to original sources
PubMed1995

Spontaneous disappearance of an aneurysmal malformation of the vein of Galen.

We describe spontaneous disappearance of an aneurysmal malformation of the vein of Galen (AMG), an anomaly that occurs most often in children, with a high mortality due to the accompanying severe cardiac failure. Spontaneous thrombosis of an AMG is rare. In this case, the AMG has been closed for about 5 years, without radiological evidence of thrombosis, and no active treatment. Proposed mechanisms of spontaneous thrombosis include slow flow shunts and severe obstruction of the venous outflow. However, in this case, the disappearance of the AMG without evidence of thrombosis indicates a different mechanisms, namely, obstruction of the feeding artery.

Cerebral Angiography↗
PubMed1994

[A patient with adult T cell leukemia in smoldering stage expressing an aberrant phenotype of CD3- and CD4+].

This report is of a patient with adult T cell leukemia (ATL) in the smoldering stage showing expression an aberrant phenotype of CD3-, CD4+ and CD8-. A 71-year-old woman was admitted to our hospital in December 1992, because of skin eruption and persistent low grade fever. Laboratory examination showed a leukocyte count of 7,000/microliter with 29% abnormal lymphocytes. The diagnosis of ATL was made by the detection of serum anti-HTLV-I antibody and the monoclonal integration of HTLV-I proviral DNA in abnormal lymphocytes. ATL cells at diagnosis were CD3+, CD4+ and CD8+. However, one month later ATL cells lacked CD3 and CD8. Three color analysis showed that most of the CD25+ cells were CD3- and CD4+.

Aged↗
PubMed1991

Organic Ca(2+)-antagonist-resistant response to FMRF-NH2 on the molluscan smooth muscle.

1. FMRF-amide (10(-7)-10(-5) M) contracted molluscan anterior byssus retractor muscle in a concentration-dependent fashion. 2. The concentration-response curve of FMRF-amide was shifted rightward by an analogue of FMRF-amide, FMRf-amide ([D-Phe4]FMRF-amide, putative FMRF-amide receptor antagonist) in a parallel manner (pA2 = 4.87 +/- 0.04). 3. Although a contractile response to KCl was reduced by the organic Ca2+ antagonists (verapamil, diltiazem and high concentration of nifedipine and nicardipine). FMRF-amide-induced contraction was not markedly reduced by them. 4. In the Ca(2+)-free medium, FMRF-amide-induced contraction was diminished. The response was also reduced by TMB-8 (10(-4) M), suggesting that FMRF-amide-induced contraction might be partly dependent on intracellular Ca2+. 5. An inorganic Ca(2+)-antagonist, MnCl2, markedly reduced the FMRF-amide- and KCl-induced contraction. The results show that FMRF-amide-induced contraction might be dependent on extracellular Ca2+. 6. These findings suggest that FMRF-amide-induced contraction might be mediated through an action on FMRF-amide receptors and not through the activation of organic Ca2+ antagonist-sensitive Ca2+ channels.

Animals↗
PubMed1990

Duodenal obstruction caused by acute appendicitis with intestinal malrotation in an adult. A case report.

A 55 year old man with a short history of continuous vomiting and recent episodes of midabdominal pain and high fever was discovered to have a complete duodenal obstruction caused by acute appendicitis and intestinal malrotation. A fibrous adhesion caused by the inflamed appendix in the high caecum involved the duodeno-jejunal junction. This case is unique in that the onset of acute appendicitis triggered duodenal obstruction in the presence of an asymptomatic malrotation.

Acute Disease↗
PubMed1988

Preferential ADP-ribosylation of arginine-3 in synthetic heptapeptide Leu-Arg-Arg-Ala-Ser-Leu-Gly.

Hen liver nuclear ADP-ribosyltransferase modified the synthetic heptapeptide Kemptide (Leu-Arg-Arg-Ala-Ser-Leu-Gly) at arginine-2 and/or arginine-3. Trypsin treatment of ADP-ribosyl-Kemptide revealed that the ADP-ribosylation of arginine-3 was constantly more abundant than that of arginine-2. ADP-ribosylation of Kemptide suppressed the subsequent phosphorylation by cyclic AMP-dependent protein kinase.

Adenosine Diphosphate↗
PubMed1988

ADP-ribosylation suppresses phosphorylation of the L-type pyruvate kinase.

L-type pyruvate kinase (EC 2.7.1.40) purified from pig liver was ADP-ribosylated by incubation with NAD and ADP-ribosyltransferase purified from hen liver nuclei. Maximal incorporation of the ADP-ribose moiety from NAD into the L-type pyruvate kinase was 0.98 mol/mol of subunit. The Km values for NAD and L-type pyruvate kinase were 0.17 mM and 9.7 microM, respectively. ADP-ribosylation of the L-type pyruvate kinase resulted in suppression of the subsequent phosphorylation catalyzed by cAMP-dependent protein kinase. The ADP-ribosylation-induced suppression of phosphorylation of the L-type pyruvate kinase also resulted in suppression of the phosphorylation-induced inactivation. Amino acid analysis, after exhaustive sequential digestion of ADP-ribosyl-L-type pyruvate kinase with pepsin, aminopeptidase M and carboxy-peptidase B showed arginine to be the ADP-ribose-accepting amino acid. These results together with finding of the ADP-ribosyltransferase activity in mammalian liver cytosol (Moss, J. and Stanley, S.J. (1981) J. Biol. Chem. 256, 7830-7833) suggest that ADP-ribosylation may participate in the regulation of the L-type pyruvate kinase activity through changes in the rate of phosphorylation.

Adenosine Diphosphate Ribose↗
PubMed1987

Hemodynamic changes during dental extraction and post-extraction bleeding in patients with prosthetic heart valves.

Hemodynamic changes during dental extraction and postextraction bleeding were retrospectively evaluated in patients with prosthetic heart valves. It was found that the rate pressure product had a higher value in the period of anesthesia and during dental extraction. There was a tendency for a high RPP difference corresponding to an increased incidence of ECG changes, such as ST-T, QRS, P, and tachycardia. ECG changes were frequently observed high in procedures which required high doses of local anesthetic at one time or when multiple dental extractions were undertaken, whereas they seemed to have no positive relation to the number of heart valves replaced. Approximately 87% of the extractions were carried out under continuous anticoagulant therapy with a pretreatment coagulability level, of which 32% had bleeding during the first 24 h.

Adult↗
PubMed1985

Amino acid sequence of histone H1 at the ADP-ribose-accepting site and ADP-ribose X histone-H1 adduct as an inhibitor of cyclic-AMP-dependent phosphorylation.

The ADP-ribosylation site of histone H1 from calf thymus by purified hen liver nuclear ADP-ribosyltransferase was determined and effects of the ADP-ribose X histone-H1 adduct on cAMP-dependent phosphorylation of the histone H1 were investigated. ADP-ribosylated histone H1 was prepared by incubation of histone H1, 1 mM [adenylate-32P]NAD and the purified ADP-ribosyltransferase. N-Bromosuccinimide-directed bisection of ADP-ribosylated histone H1 showed that the NH2-terminal fragment (Mr = 6000) was modified and contained serine residue 38, the site of phosphorylation by cAMP-dependent protein kinase. Digestion of the NH2-terminal fragment with cathepsin D and trypsin, and purification of this fragment, using high-performance liquid chromatography, yielded a radiolabelled single peptide corresponding to residues 29-34 of histone H1, containing the arginine residue as the ADP-ribosylation site. These results indicate that ADP-ribosylation of histone H1 occurs at the arginine residue 34, sequenced at the NH2-terminal side of the phosphate-accepting serine residue 38. Phosphorylation of histone H1 from calf thymus by cAMP-dependent protein kinase was markedly reduced when histone H1 was ADP-ribosylated. Kinetic studies of phosphorylation revealed that ADP-ribosylated histone H1 was a linear competitive inhibitor of histone H1 and a linear non-competitive inhibitor of ATP.

Adenosine Diphosphate Ribose↗
PubMed1985

ADP-ribosylation of phosphorylase kinase and block of phosphate incorporation into the enzyme.

Phosphorylase kinase purified from rabbit skeletal muscle was ADP-ribosylated by hen liver nuclear ADP-ribosyltransferase. This modification, as was seen in cAMP-dependent phosphorylation, was observed only in alpha and beta subunits of the phosphorylase kinase and the latter was more rapidly modified. Analysis of the ADP-ribosylated amino acid residue sequenced in alpha and beta subunits showed that both subunits were modified at the area of the arginine residue. The Km for NAD was 0.10 mM and the pH optimum was 9.0. When the ADP-ribosylated phosphorylase kinase was phosphorylated by cAMP-dependent protein kinase, a reduction in phosphate incorporation occurred with increase in the ADP-ribosylation. ADP-ribosylation also suppressed autophosphorylation, to a lesser degree than observed with cAMP-dependent phosphorylation. The ADP-ribosylation-dependent reduction of phosphorylation resulted in a suppression of the phosphorylation-dependent activation of the phosphorylase kinase. These results together with findings of ADP-ribosyltransferase activity in the rabbit skeletal muscle [Soman, G. et al. (1984) Biochem. Biophys. Res. Commun. 120, 973-980] suggest that ADP-ribosylation participates in the regulation of the phosphorylase kinase activity through changes in the rate of phosphorylation.

Adenosine Diphosphate Ribose↗
PubMed1984

Complete deficiency of adenine phosphoribosyltransferase: a report of three cases and immunologic and phagocytic investigations.

The levels of adenine phosphoribosyltransferase (APRT:EC 2.4.2.7) were determined in red blood cells (RBCs), peripheral mononuclear cells (MNCs), and polymorphonuclear leukocytes (PMNLs) from normal controls and from two families with APRT deficiency. No APRT activity was demonstrated in MNCs and PMNLs of patients with complete deficiency of RBC-APRT. APRT deficiency occurs not only in RBCs but also in MNCs and PMNLs. Immunologic and phagocytic examinations showed normal hemogram and serum immunoglobulin levels, and normal E-rosette forming cells and surface immunoglobulin-bearing cells. Lymphocyte blastogenesis in response to phytohemagglutinin and lymphocyte differentiation to cytoplasmic immunoglobulin-producing cells induced by pokeweed mitogen were normal. No major defects were apparent in natural killer activity. Phagocytic functions were normal as tested by bactericidal activity, O2-consumption, chemotaxis, and chemiluminescence response.

Adenine Phosphoribosyltransferase↗
PubMed1983

Uptake of iron and nitrilotriacetate (NTA) in rat liver and the toxic effect of Fe-NTA.

A previous study has shown that a single injection of ferric nitrilotriacetate (Fe-NTA) produces hepatic parenchymal iron loading in rats. The present paper reports on iron uptake by rat liver and iron toxicity in the liver after a single injection of Fe-NTA (7.5 mg Fe/kg B.W.). Iron uptake was examined with 59Fe-NTA and Fe-[14C]-NTA. Thirty percent of the injected 59Fe was incorporated in the liver non-heme iron fraction at 3 h and retained for 240 h. Only 1% of the 14C injected as Fe-[14C]-NTA was taken up by the liver at 3 h. Gel filtration with a Sephadex G-25 column of the supernatant fraction of the liver obtained 3 h after the injection showed two peaks of 14C activity. One was eluted in the void volume, and the other corresponded to [14C]-NTA. The former had a molecular weight of 5,000-10,000 as determined with a Sephacryl S-300 column and also had 59Fe activity. The electron spin resonance spectra showed that the generation of a free radical in the liver was initiated within 1 h of the iron administration. The free radical generated in the serum by Fe-NTA was revealed to be superoxide by the spin trapping method. These results suggest that Fe-NTA transfers iron to transferrin in the serum and induces hepatic iron loading. Small amounts of the injected iron were taken up by the liver as Fe-NTA and generated superoxide which may have induced lipid peroxidation of the cellular membranes.

Acetates↗