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Biomedical subjects

H Murakami

Publications and source records attributed to H Murakami.

At least 739 records · Page 41Linked to original sources
PubMed1983

Formation of mutagens by amino-carbonyl reactions.

The formation of mutagens by amino-carbonyl reactions of 20 kinds of amino acid and sugars after heating at 100 degrees C for 10 h was examined by the Ames test. The browned solutions of Gly, Ala, Val, Leu, Ile, Ser, Thr, Gln, Lys X HCl, Arg, Phe, Cys, Met and Pro with Glc caused mutation of Salmonella typhimurium TA100 and/or TA98 with or without S9 mix. The presence of S9 mix increased the mutagenic activity of the browned solutions of Cys and Phe with Glc on TA100 and of those of Gly, Ala, Val, Ile and Cys on TA98, but decreased the activity of other solutions. No revertants of Salmonella were induced by the browned solutions of Trp, Tyr, Asp, Asn, Glu and (Cys)2 with Glc. Among positive browned solutions, Cys, Lys, Arg and Phe had the stronger activity, but their activity was weak compared with that of pyrolysates or chemical mutagens such as Trp-P-1, Trp-P-2 and 4-nitroquinoline-N-oxide. The mutagenic activity of the browned solutions increased with prolongation of heating time and varied with the pH of the reaction mixture. Fru, Gal, Ara, Xyl, Man, Lac and Suc also had the ability to form mutagens in the browning reactions with amino acids.

Amino Acids↗
PubMed1983

Congenital coronary arterial aneurysm without arteriovenous fistula resulting in myocardial infarction--case report and review of the literature.

A 38-year-old woman with coronary arterial aneurysm, which resulted in myocardial infarction, was reported. By coronary arteriography, an aneurysm of the left anterior descending branch was found, but no arteriovenous shunt could be revealed. The patient has neither clinical history of severe febrile inflammatory disease nor any coronary risk factors. The etiology of her coronary arterial aneurysm was considered to be congenital. The patient underwent aorto-coronary saphenous vein bypass graft surgery successfully. We believe that this is the first case report in Japan on congenital aneurysm of the coronary artery without arteriovenous fistula, which was diagnosed during life by coronary arteriography.

Adult↗
PubMed1983

Studies on concurrent alpha- and beta-adrenoceptor blocking action of S-596 (arotinolol).

The effects of a therapeutic dose of oral S-596 upon the cardiovascular response to intravenous isoproterenol and noradrenaline were studied in 2 hypertensive and 4 normotensive subjects in order to evaluate the drug's mode of action. After oral administration of S-596, mean blood pressure rose slightly and the heart rate decreased. In addition, cardiac output decreased considerably and total peripheral resistance increased. However pulmonary arterial end-diastolic pressure and right atrial pressure were not affected by S-596 administration. Before S-596, intravenous isoproterenol increased both heart rate and pulse pressure in a dose-dependent manner. Similarly, intravenous noradrenaline increased both systolic and diastolic pressures. Following 15 mg of S-596, the effects of isoproterenol were antagonized such that the cumulative log-dose-response curves of the mean isoproterenol-induced increases in heart rate and reductions in diastolic pressure were shifted in parallel to the right. At the same time, the mean noradrenaline-induced increases in blood pressure were also antagonized in a competitive manner. The mean ratio of alpha- and beta-components was calculated as: (formula: see text) From this result it can be suggested that the alpha-adrenoceptor blockade potency of this drug is approximately one-eight of its beta-adrenoceptor blockade potency.

Adrenergic alpha-Antagonists↗
PubMed1983

Electrophoretic study on the DNA-breaking actions of ascorbic acid and triose reductone in the presence of Cu2+.

The mode of DNA-breaking actions of ascorbic acid (AsA) and triose reductone (TR) in the presence of Cu2+ was studied by use of 0.8% agarose slab gel electrophoretic analysis. The DNA-breaking actions of the mixture of AsA or TR and Cu2+ were inhibited by N2 gas, hydroxyl radical scavengers and catalase, indicating that the oxidation of AsA or TR by Cu2+ and the hydrogen peroxide and hydroxyl radicals resulting from the oxidation are essential for the fragmentation of DNA by the mixture of AsA or TR and Cu2+. However, the DNA-breaking activity of these reductones varied with pH, while their oxidation rates were proportional to the increase in pH. The marked fragmentation of DNA occurred at pH 4, 7 or 8. The breakages of DNA by AsA or TR in the presence of Cu2+ were concluded not to be associated with the oxidation rates of reductones.

Animals↗
PubMed1983

Function of Cu2+ on the DNA-breaking actions of ascorbic acid and triose reductone.

The role of Cu2+ on the DNA-breaking action of ascorbic acid (AsA) and triose reductone (TR) was studied with an agarose slab gel electrophoretic analysis. AsA and TR decomposed calf thymus DNA which had been pretreated with Cu2+, and their decomposing activity was proportional to the concentration of Cu2+ bound to the DNA. The DNA-Cu2+ complex had the ability to oxidize reductones. AsA and TR also decomposed the pretreated DNA with Cu2+ more markedly than that pretreated with Cu2+ and successively with EDTA. The DNA-breaking activity of AsA and TR showed no Cu2+-concentration dependency. The maximal fragmentation of DNA occurred at the concentration ratio of DNA and Cu2+ of 4:1. Excess concentration of Cu2+ decreased the activity of reductones. The present results indicate that the binding of Cu2+ to DNA molecules is also essential for the DNA-breaking action of AsA and TR in the presence of Cu2+ and that Cu2+ bound to DNA molecules has more effective promoting activity than free Cu2+.

Animals↗
PubMed1983

lambda DNA-fragmenting actions of ascorbic acid and triose reductone in the presence of Cu2+.

Lambda DNA-fragmenting actions of ascorbic acid (AsA) and triose reductone (TR) in the presence of Cu2+ were studied. The mixture of AsA or TR and Cu2+ caused a marked fragmentation of lambda DNA (3.2 X 10(7) daltons) within the first 1 min of reaction. Further incubation resulted in accumulation of the most abundant species of fragmented lambda DNA having a molecular weight of 1.3 X 10(5) daltons. The mixture of AsA or TR and Cu2+ fragmented calf thymus DNA to produce the fragmented DNA of which 5'-OH terminal groups have a mixture of free OH groups and phosphodiester linkage. The mixture of AsA or TR and Cu2+ was also found to fragment lambda DNA to produce dCMP predominantly as 5'-OH terminal nucleotides.

Adenosine Triphosphate↗
PubMed1983

Experimental autoimmune hepatitis in mice after immunization with syngeneic liver proteins together with the polysaccharide of Klebsiella pneumoniae.

Experimental autoimmune hepatitis could be produced in SMA mice by monthly injections of syngeneic liver homogenate or liver-specific lipoprotein together with the polysaccharide of Klebsiella pneumoniae 03:K1 as a powerful adjuvant. Using a gel-diffusion technique, antibodies reacting with liver-specific lipoprotein and liver-specific membrane lipoprotein were detected in approximately 50% of sera from the immunized mice after an 8-mo period. After a full immunization schedule, 60%-80% of the livers of the sensitized mice developed infiltration of mono-nuclear cells consisting mainly of lymphocytes and plasma cells in portal areas, frequently associated with focal necrosis of hepatocytes. Moderate-to-severe piecemeal necrosis of hepatocytes appeared in 10 of 59 animals. However, a gradual decrease in the morphologic severity was observed 3-6 mo after cessation of injections. The transfer of splenic cells from animals with the damaged liver led to a hepatitis in recipients that was characterized by portal infiltration with mononuclear cells and by necrosis of liver parenchymal cells seen on day 14 after cell transfer. The suppressor cell activity determined by the ability of concanavalin A-activated cells to suppress blast transformation of splenic cells of normal SMA mice was significantly decreased (p less than 0.05) in mice immunized with a mixture of liver-specific lipoprotein and the polysaccaride of Klebsiella pneumoniae compared with mice immunized with the polysaccaride of Klebsiella pneumoniae alone or the polysaccaride of Klebsiella pneumoniae plus kidney lipoprotein.

Animals↗
PubMed1983

Activation of suppressor function of human peripheral blood T cells by (+)cyanidanol-3: its application to chronic active liver diseases.

(+)Cyanidanol-3, a substance belonging to the flavonoids group, has been used in acute viral hepatitis (AVH) and chronic active liver disease (CALD). Studies were undertaken to determine if (+)cyanidanol-3 could affect a function of mitogen stimulated peripheral blood lymphocytes (PBL) in humans. First, (+)cyanidanol-3 was added directly to pokeweed mitogen (PWM) stimulated PBL or co-culture of B and T cells resulting in severe suppression of immunoglobulin (Ig) production. This suppression was mediated by radiosensitive T cells. Secondly, when normal T cells pre-incubated with 25 micrograms/ml of (+)cyanidanol-3 for 48 h were cultured with freshly prepared autologous or allogeneic normal PBL in the presence of PWM, Ig production was markedly suppressed. Similarly, there was a consistent suppression of blast transformation of concanavalin A (Con A) stimulated autologous or allogeneic responding PBL by (+)cyanidanol-3 pre-treated normal T cells. On the other hand, (+)cyanidanol-3-induced suppressor cell activity of T cells from patients with CALD was significantly decreased (P less than 0.001) when compared with that of normal individuals. These studies may explain the therapeutic effect of (+)cyanidanol-3 on certain types of liver disease.

Benzopyrans↗
PubMed1983

B lymphocyte function stimulated by staphylococcus aureus Cowan I in chronic liver disease.

Peripheral blood B cell response to staphylococcus aureus (SpA) Cowan I was evaluated in 8 healthy subjects, 8 patients with liver cirrhosis (LC), and 2 patients with chronic active hepatitis (CAH) with hypergammaglobulinemia (greater than 2 g/dl). In control studies it was shown that stimulation by SpA Cowan I was much less T cell-dependent than that induced by pokeweed mitogen (PWM) or con-canavalin A (ConA) when the amounts of immunoglobulins (Ig) secreted into culture supernatants were measured by radioimmunoassay (RIA) and the blastogenic response was measured by incorporation of tritiated thymidine. B cells from only 2 patients revealed increased Ig synthesis by SpA Cowan I stimulation. In the study of blastogenic response, increased DNA synthesis of B cells by SpA Cowan I stimulation was observed in 2 patients and decreased DNA synthesis in 3 patients. The remaining patients demonstrated normal range response. There was no correlation between B cell response to SpA Cowan I and clinical data such as gammaglobulin level in the patients studied. These studies indicate that B cell function remains intact in many patients with chronic liver disease with hypergammaglobulinemia.

Adult↗
PubMed1983

[Central pontine myelinolysis--pathogenesis and review of the literature].

A 77-year-old, nonalcoholic man was admitted to the Omiya Red Cross Hospital with the complaint of fever and delirium state of two days' duration. Two months prior to admission he had had cough and sputum. Chest X-ray revealed honey comb lungs. Cultures of sputum revealed mycobacterium tuberculosis after eight weeks incubation. He had no liver disease in his past history. The patient appeared cachetic. His vital signs were as follows; temperature 38 degrees C, blood pressure 132/68 mmHg, with a pulse rate of 84/min. He was delirium and excited. Findings of the cranial, motor and sensory nerve examination were normal. Initial laboratory studies showed a serum sodium value of 133 mEq/l, potassium 4.5 mEq/l, chloride 98 mEq/l; a serum GOT value of 51 units, GPT 36 units; a total protein content of 7.8 g/dl and ESR rate of 87 mm/hr. Six days after admission, the patients' consciousness level began to stupor and nuchal rigidity was appeared. Spinal fluid examination revealed opening pressure 270 mm H2O, cell counts 720 (N 712, L 8)/cumm, sugar 57 mg/dl and protein 170 mg/dl. Spinal fluid cultures were positive in mycobacterium tuberculosis after eight weeks incubation. Laboratory studies showed a serum sodium value of 114 mEq/l, potassium 4.4 mEq/l, chloride 86 mEq/l, a serum osmorality (SeOs) 225 mOsm/l and urine osmorality (UOs) 958 mOsm/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗