PubMed Health⌕ Search

Biomedical subjects

A Sawamura

Publications and source records attributed to A Sawamura.

At least 19 recordsLinked to original sources
PubMed1992

Usefulness of taurine in chronic congestive heart failure and its prospective application.

We compared the effect of oral administration of taurine (3 g/day) and coenzyme Q10 (CoQ10) (30 mg/day) in 17 patients with congestive heart failure secondary to ischemic or idiopathic dilated cardiomyopathy, whose ejection fraction assessed by echocardiography was less than 50%. The changes in echocardiographic parameters produced by 6 weeks of treatment were evaluated in a double-blind fashion. In the taurine-treated group significant treatment effect was observed on systolic left ventricular function after 6 weeks. Such an effect was not observed in the CoQ10-treated group.

Administration, Oral↗
PubMed1991

Plasma endothelin levels during myocardial ischemia and reperfusion.

Endothelin, an endothelium-derived vasoconstrictive peptide, has a strong potency of coronary artery constriction. However, the role of endogeneous endothelin under pathophysiological conditions has not yet been known. In this study, we examined plasma endothelin concentration in dogs with myocardial ischemia and reperfusion. Anesthetized open-chest dogs underwent either 45 minutes occlusion of the left anterior descending coronary artery followed by 3 hours reperfusion, or 4-10 hours of continuous occlusion. Plasma concentration of endothelin from the central vein was measured by the highly sensitive enzyme-immunoassay. Plasma endothelin concentration increased 2.2-fold with the peak level at 60 minutes after release of the ligated artery, but occlusion per se caused no remarkable change. These data suggest that reperfusion of the occluded artery might be needed to increase the plasma concentration of endothelin in case of myocardial infarction.

Animals↗
PubMed1991

[Study on the intra-tumor tissue concentration of zinostatin stimalamer in the liver following intra-arterial injection of zinostatin stimalamer (YM881) suspension].

A suspension of zinostatin stimalamer (YM881), an antitumor protein antibiotic in iodized poppy oil-fatty acid ester, was injected into the hepatic artery of 2 patients who received surgical treatment of hepatic tumors. Single doses of 4 mg of zinostatin stimalamer were injected into the hepatic artery by Seldinger's method. Two and 4 weeks after the dose, tissue samples were collected from the tumor and non-tumor regions close to and distant (normal tissues) from the tumor, and zinostatin stimalamer concentrations in these tissues were assayed by RIA. In one of the two patients, plasma concentrations of the drug were also assayed. Concentrations of zinostatin stimalamer in the tumor tissues (381.8 ng/g) were about 55 times greater than those in the normal tissue (6.9 ng/g) in patient No. 1 (week 4), and about 17 times in patients No. 2 (13.9 ng/g in the normal tissue and 229.8 ng/g in the tumor tissues in week 2). Plasma concentrations were assayed in patient No. 2, and were 510.3 ng/ml after one hr., 385.3 ng/ml after 3 hrs., 184.4 ng/ml after 6 hrs., and 45.4 ng/ml after 24 hrs., with a half life of 7.1 hrs. These results indicate that zinostatin stimalamer suspended in iodized poppy oil fatty acid ester persisted in the hepatic tumor tissues at the high concentrations, when injected into the hepatic artery, but was eliminated fairly rapidly from the plasma.

Aged↗
PubMed1991

[Loco-regional cancer therapy for hepatic metastasis].

UNLABELLED: We undertook a clinical evaluation of chemotherapy for hepatic metastasis of gastric, colorectal and breast cancer. Between 1980 and 1989, chemotherapy for hepatic metastasis of gastric cancer was performed in 96 cases. Between 1973 and 1989, chemotherapy for hepatic metastasis of colorectal cancer and breast cancer was performed in 40 and 14 cases. RESULTS: (1) In hepatic metastasis of gastric cancer, the 50% survival period was 149 days in local injection therapy, 132 days in arterial infusion therapy and 117 days with no chemotherapy. There was no significant difference in the survival period in gastric cancer. (2) In hepatic metastasis of colorectal cancer, the 50% survival period was 445 days in arterial infusion therapy, 206 days in local injection therapy and 96 days with no chemotherapy. The survival period with hepatic metastasis of colorectal cancer that had undergone chemotherapy was longer than for no chemotherapy. (3) In hepatic metastasis of breast cancer, arterial infusion therapy was more effective, and the survival period was prolonged significantly.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[Case report: a foreign body (gauze) in the bladder].

A case of bladder tamponade caused by a foreign body (gauze) in the bladder of a 24-year-old man is reported. He had been treated with the Lambotte wire and screw to repair his pubic bone fracture caused by a traffic accident. About one year later, the wire and screw were removed from the patient. However, he suffered from gross hematuria and bladder tamponade on the 11th day after the 2nd operation, and he was transferred to our outpatient department on emergency. Further urological examinations were done for this case. The patient was diagnosed as having bladder tamponade caused by a foreign body, a gauze, in the bladder. Among these examinations NMR-CT gave us the most interesting and useful findings. NMR-CT showed that the gauze penetrated the bladder wall.

Adult↗
PubMed1990

Taurine modulates ion influx through cardiac Ca2+ channels.

The effects of taurine on the inward Ca2+ current (ICa) were investigated by means of the whole-cell voltage-clamp technique in isolated single guinea pig ventricular myocytes. ICa were elicited by 200-ms test pulses from a conditioning holding potential of -45 mV to various test potentials at a rate of 0.5 Hz. Taurine (10-20 mM) had different effects on ICa, depending on the extracellular Ca2+ concentration [( Ca]o). A small stimulatory effect of taurine was found in low [Ca]o (0.8 mM), and a small inhibitory effect was found in high [Ca]o (3.6 mM). Taurine had no significant effect on ICa in normal [Ca]o (1.8 mM). Such dual effects on ICa may explain the various effects reported for taurine especially its dual inotropic actions on cardiac muscle depending upon [Ca]o. Thus, taurine acts in a manner to keep ICa relatively constant. Taurine increased the resting potential irrespective of [Ca]o, suggesting that, in addition, taurine increased K+ conductance and/or ion exchange systems such as the Na/Ca and Na/K exchange.

Action Potentials↗
PubMed1989

Isolation of a new form of cytochrome P-450 with prostaglandin A and fatty acid omega-hydroxylase activities from rabbit kidney cortex microsomes.

Two different forms of cytochrome P-450, highly active in the omega-hydroxylation of prostaglandin A, and the omega- and (omega-1)-hydroxylation of fatty acids (P-450ka-1 and P-450ka-2), have been purified from kidney cortex microsomes of rabbits treated with di(2-ethylhexyl)-phthalate. On the basis of the peptide map patterns and NH2-terminal amino acid sequence, P-450ka-1 was determined to be a new form of omega-hydroxylase cytochrome P-450, whereas P-450ka-2 is identical to P-450ka reported earlier. The first 20 NH2-terminal amino acid sequence (ALNPTRLPGSLSGLLQVAGL) and (ALSPTRLPGSFSGFLQAAGL) of P-450ka-1 and P-450ka-2 showed 90 and 80% homology with that of the lung prostaglandin omega-hydroxylase, respectively, suggesting that these three cytochromes P-450 are members of the same omega-hydroxylase cytochrome P-450 gene family.

Amino Acid Sequence↗
PubMed1988

The regulation of natural killer cell activity by splenic nonspecific suppressor cells and its modification in cancer patients.

Spleen cells (SC), splenic venous blood lymphocytes (SVL) and peripheral blood lymphocytes (PBL) from gastric and esophageal cancer patients were simultaneously tested for natural killer (NK) and nonspecific suppressor (Ts) cell activities. Furthermore, the influence of Ts activity on the augmentation of NK activity by a biological response modifier (BRM) was also investigated. Positive Ts activities were frequently detected in the SC, SVL and PBL of advanced cancer patients. The NK activities of SC and SVL were maintained even in advanced cancer patients, though significantly depressed NK activities were observed in the PBL of advanced cases. Cancer patient SC, SVL and PBL with positive Ts activity showed low NK activities. Moreover, the NK activities of SVL and PBL were low in the patients with positive Ts activity in SC. The NK activity of normal control PBL was strongly augmented by interleukin 2, interferon and OK-432. These BRMs exhibited comparable capacities to augment the NK activities of SC, SVL and PBL with negative Ts activity in cancer patients, however, the effects of these agents seemed to be low in cells with a positive Ts activity. These results suggested that NK activity might be regulated by nonspecific suppressor cells and the presence of suppressor cells might affect the augmentation of NK activity through BRM in circulating blood lymphocytes and also in spleen cells.

Adult↗
PubMed1988

Cellular oncogene expression in the idiopathic cardiomyopathic hamster heart during the growing process.

The expression of various proto-oncogenes was evaluated in the Syrian hamster with hereditary idiopathic cardiomyopathy. mRNA from the heart and aorta of controls (BIO-RB) and cardiomyopathic hamsters (UM-X7.1 strain, BIO 14.6 line) was tested using RNA hybridization techniques. Of the 19 different v-oncogene probes used in the study, only the v-myc probe revealed a substantially greater expression of oncogene in the 30th day of cardiomyopathic hamster heart than in control hamster heart. The amplified expression of c-myc was also observed in the heart of 1-year-old, but not of 7-day-old cardiomyopathic hamster. Overexpression of c-myc, otherwise associated with the regulation of cell differentiation or rapid growth, may relate to the pathological state or pathogenesis of the hereditary cardiomyopathy.

Age Factors↗
PubMed1988

Protective effect of taurine on the irregular beating pattern of cultured myocardial cells induced by high and low extracellular calcium ion.

Abnormal beating patterns were induced in spontaneously contracting cultured embryonic mouse myocardial cells either by elevating or by lowering extracellular calcium. At low calcium (0.4 mM), the number of beating cells and beating rate decreased while the number of arrhythmic cells increased. By contrast, at high calcium (20 mM), the number of beating cells decreased while beating rate and the number of arrhythmic cells increased. Addition of taurine (20 mM) to the medium attenuated the response to varying calcium; the taurine effect appeared to be specific since neither taurine analog tested (beta-alanine nor glycine) provided much protection against these abnormalities. The protective effect of taurine also appeared to differ from that of verapamil, which was effective only in decreasing beating rate in the high calcium condition. Uptake of 14C-taurine by the cells was higher at both low and high extracellular calcium when compared to the normal calcium (2 mM) concentration. The results raise the possibility that the protective effect of taurine on beating abnormalities caused by low or high calcium is related to taurine uptake.

Animals↗
PubMed1988

Mechanism of the protective action of taurine against isoprenaline induced myocardial damage.

The effect of the sulphur amino acid, taurine, on the biochemical changes induced by a toxic dose of isoprenaline was examined in chick hearts. Isoprenaline treatment (80 and 240 mg.kg-1 subcutaneously twice a day for four days) caused a dose dependent increase in heart to body weight ratio. Isoprenaline administration induced a substantial accumulation of calcium and caused a profound decrease of adenosine triphosphate content and creatine phosphokinase activity in the myocardium. A pronounced increase in lipoperoxide and decrease in phospholipid and reduced glutathione concentrations were also seen. Oral administration of taurine (200 mg.kg-1 for seven days) partially protected against these changes induced by isoprenaline. It is suggested that the beneficial effect of taurine may be due in part to inhibition of lipoperoxide formation and calcium accumulation and to protection against the deterioration of membrane phospholipids.

Adenosine Triphosphate↗