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Dive into the research topics where Tatsuya Sekiyama is active.

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Featured researches published by Tatsuya Sekiyama.


Journal of Hepatology | 1992

Long-term haemodynamic effects of a 4-week regimen of nipradilol, a new β-blocker with nitrovasodilating properties, in patients with portal hypertension due to cirrhosis: A comparative study with propranolol

Takumi Aramaki; Tatsuya Sekiyama; Yasumi Katsuta; Hiroshi Kurokawa; Hirokazu Komeichi; Hitoshi Tsutsui; Hideto Terada; Masaru Ohsuga; Katsuaki Satomura; Hidemasa Okumura

To study the long-term effects of pharmacological combination therapy, a comparison was made of the haemodynamic changes in patients with cirrhosis and portal hypertension following a 4-week treatment of propranolol or nipradilol, a new nonselective beta-blocker with nitrovasodilating effect. Nipradilol (12 mg/dag, n = 12) significantly diminished wedged hepatic venous pressure (WHVP, 25 +/- 16%), the hepatic venous pressure gradient (HVPG, 20 +/- 12%), and estimated hepatic blood flow (EHBF, 18 +/- 16%). Propranolol (30 mg/day, n = 11) also caused a significant reduction in WHVP (22 +/- 21%) and HVPG (24 +/- 21%), but not in EHBF. The percentage of portal pressure reduction and the frequency of nonresponders did not differ between the nipradilol and propranolol groups. Both agents reduced heart rate by approx. 20%. Nipradilol, however, did not cause a significant reduction in cardiac index (CI) versus a 14% reduction by propranolol. Pulmonary capillary wedge pressure and central venous pressure, an index of preload, were decreased slightly in the nipradilol group. When nonresponders were excluded, there was a significant correlation of the percentage of reduction between WHVP and CI or systemic vascular resistance, in the nipradilol group. These results indicate that nipradilol may have potent hypotensive effects on portal hypertension, similar but not superior to propranolol. Nipradilol, at the dosage used in the present study, did not appear to exert a nitrovasodilating effect to enhance the portal pressure reduction induced by beta-blocking action.


Journal of Hepatology | 1993

Plasma volume contraction in portal hypertension

Yasumi Katsuta; Takumi Aramaki; Tatsuya Sekiyama; Katsuaki Satomura; Kidemasa Okumura

The effect of blood volume contraction induced by a 4-week regimen of spironolactone (100 mg/day) or furosemide (40 mg/day) on the hepatic venous pressure gradient (HVPG), an indicator of portal hypertension, was evaluated in patients with cirrhosis and no ascites. In the spironolactone group (n = 15), HVPG decreased significantly from 16.5 +/- 0.9 mmHg (mean +/- S.E.M.) to 12.9 +/- 1.0 mmHg (P < 0.005) and total blood volume contracted significantly from 4338 +/- 231 ml to 4006 +/- 203 ml (n = 14, P < 0.01). Although the HVPG changes did not correlate significantly with changes in measured total blood volume or in simultaneously determined systemic haemodynamics, a significant inverse correlation (r = -0.74, P < 0.01, n = 12) was found between the HVPG change and posttreatment plasma aldosterone levels, attesting to the effectiveness of spironolactone therapy in lowering HVPG. In the furosemide group (n = 10), neither HVPG (13.7 +/- 0.3 mmHg vs. 13.6 +/- 0.9 mmHg) nor total blood volume (4961 +/- 153 ml vs. 4964 +/- 162 ml) declined significantly. These results show that long-term administration of spironolactone to patients with cirrhosis and no ascites produced a significant reduction in HVPG that may have been due to gradual, sustained volume contraction. Thus, spironolactone may prove to be an effective treatment for portal hypertension in cirrhosis without ascites.


Scandinavian Journal of Gastroenterology | 1990

Regional Differences in Peripheral Circulation between Upper and Lower Extremity in Patients with Cirrhosis

Hidemasa Okumura; Takumi Aramaki; Yasumi Katsuta; Hideto Terada; Katsuaki Satomura; Masahiro Akaike; Tatsuya Sekiyama

In 42 patients with compensated cirrhosis and 31 control subjects, blood flow (BF) and vascular resistance (VR) were measured at the forearm and calf, using a pneumoplethysmograph. In some of the subjects deep-body temperature (DBT) was also measured by the zero heat flow method. In cirrhosis, BF and DBT were significantly higher and VR was significantly lower in the forearm than in the calf. Corresponding differences were not observed in control subjects. When these indices of the forearm were compared between cirrhosis and controls, BF and DBT were significantly higher and VR was significantly lower in cirrhosis than in controls. In cirrhotics in whom the gradient between forearm BF and calf BF was 1 ml.dl-1.min-1 or more (forearm greater than calf), the vascular response of the forearm to cold stimulation was reduced, whereas in the remaining patients and in controls the forearm BF and VR responded significantly. These results suggest that there is a regional difference in peripheral circulation in cirrhotics, partly with participation of impaired sympathetic nervous activity, which may account for the selective distribution observed in the clinical manifestations of vascular spider, palmar erythema, and warm hand, inclined toward the upper extremities or the upper part of the body.


Clinical Drug Investigation | 1998

Effects of Aging and Liver Disease upon the Pharmacokinetics of Nipradilol

Takumi Aramaki; Yasumi Katsuta; Tatsuya Sekiyama; Hitoshi Tsutsui; Hirokazu Komeichi; Masaru Ohsuga; Katsuaki Satomura; Mitsuo Yoshimura

AbstractObjective: The effects of aging and liver disease on the pharmacokinetics of nipradilol were studied after a single oral dose of 6mg. Study Participants: Nipradilol was administered to three groups of subjects: younger healthy volunteers with a mean age of 33.2 years (group I, n = 6), older subjects without hepatic dysfunction with a mean age of 55.5 years (group II, n = 6), and patients with histologically confirmed cirrhosis of the liver with a mean age of 55.4 years (group III, n = 8). Results: When compared with younger subjects (group I), the older subjects (group II) had a significantly longer time to maximum concentration, a greater area under the plasma concentration-time curve (AUC), a greater bioavailability (F), and a greater 24-hour urinary excretion of nipradilol. There was also a tendency towards a longer half-life in group II compared with group I. Cirrhotic subjects (group III) showed the same differences relative to group I. In addition, F was significantly larger and the plasma clearance was significantly decreased in group III compared with group II. Nearly identical results were demonstrated for the pharmacokinetics of denitrated nipradilol, one of the major metabolites of the test drug. A significant correlation was demonstrated between the AUC of nipradilol and age when groups I and II were combined. Conclusion: It was concluded that the pharmacokinetics of nipradilol may be altered with aging and hepatic dysfunction, and that changes in metabolism are likely to be a major factor.


Kanzo | 1985

Case report of primary biliary cirrhosis, followed over a period of 19 years.

Hidemasa Okumura; Tatsuya Sekiyama; Takumi Aramaki; Katsuaki Satomura; Yasumi Katsuta; Masahiro Akaike; Hideto Terada; Naomi Inokuchi

我々は19年間follow upされた59歳の原発性胆汁性肝硬変の女性を報告する.患者は1965年,高血圧の検査の為に入院し,肝機能異常を発見され,第1回の肝生検が行われ,軽度の細胞浸潤を伴った線維化の診断であった.第1回の入院14年後に,胆のう腫瘍の疑いで胆のう摘出術が行われ,肝組織もとられた.1980年血清ビリルビンとIgMの増加と抗ミトコンドリア抗体陽性となり,第3回目の肝生検が行われ,chronic nonsuppurative destructive cholangitisの組織像がえられた.1984年肝性脳症の治療で入院中,肺炎を合併して死亡,剖検された.5回えられた肝の組織変化,19年間follow upされた肝機能検査と抗ミトコンドリア抗体の変化について記載した.


Journal of Nippon Medical School | 1995

Portal and systemic hemodynamic responses to a very low dose of nitroglycerin in cirrhotic patients with portal hypertension

Hiroshi Kurokawa; Tatsuya Sekiyama; Yasumi Katsuta; Takumi Aramaki


Kanzo | 1984

Effect of propranolol on portal venous pressure in patients with chronic liver disease: comparison with vasopressin.

Hidemasa Okumura; Tatsuya Sekiyama; Yasumi Katsuta; Takumi Aramaki; Katsuaki Satomura; Masahiro Akaike; Hideto Terada; Mitsuya Sekino


Journal of Nippon Medical School | 2000

Effects of SSM (Specific Substance Maruyama) on HBe Antigen-Positive Chronic Hepatitis B

Katsuaki Satomura; Mingshi Yin; Tatsuya Sekiyama; Shigeko Fujisaki; Takumi Aramaki; Hidemasa Okumura; Yasukazu Ohmoto


Journal of Nippon Medical School | 2000

Effects of SSM(Specific Substance Maruyama)on HBe Antigen‑Positive Chronic Hepatitis B Clinical Efficacy and Modulation of Cytokines

Katsuaki Satomura; Mingshi Yin; Tatsuya Sekiyama; Shigeko Fujisaki; Takumi Aramaki; Hidemasa Okumura; Yasukazu Ohmoto


Journal of Nippon Medical School | 1984

Immunomodulatory treatment of HBsAg positive chronic hepatitis with specific substance Maruyama (SSM).

Hidemasa Okumura; Katsuaki Satomura; Takumi Aramaki; Yasumi Katsuta; Hideto Terada; Tatsuya Sekiyama; Masahiro Akaike; Minoru Otake; Keishiro Fujita; Chisato Maruyama

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