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Yasuhiro Nakamura

Publications and source records attributed to Yasuhiro Nakamura.

56 records · Page 4Linked to original sources

Nipradilol can prevent left ventricular systolic and diastolic dysfunction after myocardial infarction in rats.

The purpose of this study was to examine the effects of nipradilol on the cardiac function and mRNA expression in Wistar rats with a myocardial infarction (MI) that was created by ligation of the anterior descending coronary. Ten mg x kg(-1) x day(-1) of nipradilol were administrated to the rats in random order, and hemodynamic and Doppler-echocardiographic findings and myocardial mRNA expression were analyzed at 4 weeks after MI. Although left ventricular end-diastolic pressure (LVEDP) and central venous pressure (CVP) were increased in the MI rats, nipradilol significantly reduced the degree of the increase in both parameters. MI also significantly increased the weight of the left and right ventricles, and increased the left ventricular end-diastolic dimension (LVDd), effects that were attenuated by nipradilol. The MI rats showed decreased fractional shortening as systolic dysfunction and decreased E wave deceleration rate as diastolic dysfunction, and nipradilol significantly prevented these. Nipradilol significantly suppressed the increase in the non-infarcted myocardial mRNA expression of atrial natriuretic peptide, brain natriuretic peptide and collagen I and III. In conclusions, nipradilol prevents the cardiac remodeling that is accompanied by systolic and diastolic dysfunction, and inhibits abnormal myocardial gene expression after MI.

Adrenergic beta-Antagonists↗

In situ androgen production in human gastric carcinoma--androgen synthesizing and metabolizing enzymes.

BACKGROUND: It is well known that the incidence of gastric carcinoma is lower in females than in males. Therefore, androgens have been proposed to play an important role in modifying the development of gastric carcinoma. 5Alpha-reductase (5alpha-reductase) types 1 and 2 and 17beta-hydroxysteroid dehydrogenase type 5 (17beta-HSD type 5) are considered important local regulators of androgen production in human androgen-responsive tissues and cancer. MATERIALS AND METHODS: The immunoreactivities of these steroidogenic enzymes, as well as of the androgen receptor (AR), were evaluated in human gastric carcinoma obtained from endoscopic mucosal resection (EMR) (n = 117). RESULTS: 17beta-HSD type 5 immunoreactivity was detected in 99 cases (85%), 5alpha-reductase type 1 in 69 cases (59%), 5alpha-reductase type 2 in 57 cases (49%) and AR in 46 cases (39%). CONCLUSION: These androgen-producing enzymes are expressed in human gastric carcinomas and are involved in the in situ production and possible regulation of androgenic activity in human gastric carcinoma.

17-Hydroxysteroid Dehydrogenases↗