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Biomedical subjects

A Yashiro

Publications and source records attributed to A Yashiro.

8 recordsLinked to original sources

Heparin-releasable platelet factor 4 in patients with coronary artery disease.

Recently, platelet factor 4 (PF4) release by heparin (heparin-releasable PF4) has been examined as a useful marker of the interaction between the substances liberated from circulating platelets and the vascular endothelium. We compared the plasma levels of PF4 and beta-thromboglobulin (beta-TG) after intravenous heparin injection in patients with coronary artery disease (CAD) and normal control subjects. We also studied the effects of low-dose aspirin (81 mg/day) on the plasma level of heparin-releasable PF4 in the CAD patients. Blood samples were obtained before and 5 min after the intravenous injection of heparin (1,000 IU) from 23 patients with CAD and 15 normal control subjects. Although the plasma beta-TG level remained unchanged after heparin injection, the plasma PF4 level markedly increased in both groups. There was a significant difference in plasma PF4 levels at 5 min after heparin injection between the CAD group (100.1 +/- 38.1) and the control group (61.0 +/- 24.0) (p less than 0.01). The PF4/beta-TG ratio after heparin injection was also higher in the CAD group than in the control group (p less than 0.01). There was a correlation between the PF4/beta-TG ratio after heparin and the Gensini CAD score, which defines the severity of coronary atherosclerosis (r = 0.489, n = 23, p less than 0.01). Low-dose aspirin was administered to 11 CAD patients for 246.0 +/- 28.8 days. Blood samples for the assay of PF4 and beta-TG were obtained as stated above, and platelet aggregation, thromboxane B2 (TxB2), and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) levels were also measured before and during aspirin administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Sustained-release nifedipine (nifedipine-L) suppresses plasma thromboxane B2 and 6-keto prostaglandin F1 alpha in both young male smokers and nonsmokers.

Sustained-release nifedipine (nifedipine-L) (40 mg twice a day) was administered orally to healthy young adult male smokers and nonsmokers for 10 days, and its effects on platelet aggregation, beta-thromboglobulin and platelet factor 4 levels, and plasma thromboxane B2 (TxB2) and 6-ketoprostaglandin F1 alpha (6-Keto-PGF1 alpha) concentrations were studied. The plasma nifedipine-L concentration in smokers (46.0 +/- 7.4 ng/ml) was significantly lower than that in nonsmokers (88.2 +/- 1.2 ng/ml). Nifedipine-L did not affect platelet aggregation induced by adenosine diphosphate, collagen, or epinephrine in either smokers or nonsmokers. The plasma beta-thromboglobulin level on the tenth day of nifedipine-L administration in nonsmokers was lower than that in smokers, but there were no significant differences either with or without nifedipine-L or between nonsmokers and smokers. Nifedipine-L had no effect on the concentration of platelet factor 4 in either smokers or nonsmokers. On the other hand, nifedipine-L significantly decreased the plasma TxB2 and 6-keto-PGF1 alpha concentrations in both smokers and nonsmokers. Thus we concluded that nifedipine-L suppressed the production of plasma TxB2 from platelets and also subsequently suppressed the production of 6-keto-PGF1 alpha and that this action was not affected by cigarette smoking.

6-Ketoprostaglandin F1 alpha

Factors predictive of marked decrease in HDL-C by probucol treatment.

Probucol markedly reduces the LDL-C level in hyperlipidemic patients. However, it also reduces HDL-C which is believed to result in an anti-atherosclerotic effect. Many hyperlipidemic patients treated with Probucol show a marked reduction in the HDL-C level, and administration of the agent to these patients requires proper caution. In this study, factors useful for predicting the reduction in HDL-C were examined in order to be able to predict the problem before actual administration. Probucol (250-750 mg/day) was administered to 30 patients with type II hypercholesterolemia. Among them, 23 patients showed a decrease greater than 20% in the HDL-C level after administration. To evaluate the factors which permit identification of this group, linear descriminant function analysis was performed using 12 pre-administration lipid levels. The analysis indicated that the Apo A-I/HDL-C ratio before Probucol has the greatest predictive value (F = 17.8, P less than 0.01) of all the parameters, and that the HDL-C level is reduced by 20% or more by Probucol administration when this ratio is 5.3 or less.

Aged

Effects of polysulfated glycosaminoglycans obtained from bovine lung tissue on hypercholesterolemic rabbits.

Sixteen rabbits were fed a 1% cholesterol diet with an intraperitoneal injection of saline (n = 8) (cholesterol-diet group), or 50 mg glycosaminoglycans-polysulfate (GAG-PS) (n = 8) (GAG-PS group). After 10 weeks all rabbits were sacrificed and studied. Eight rabbits on a standard diet with an intraperitoneal injection of saline (n = 8) (standard-diet group) were processed in the same manner. After 10-weeks of feeding, the plasma total cholesterol of the GAG-PS group was significantly lower than that of lower than that of the control group (P less than 0.02). The VLDL cholesterol of the GAG-PS group was also significantly lower than that of the cholesterol-diet group. There were no differences in LDL-cholesterol, HDL-cholesterol or plasma triglycerides between the groups. Total lipoprotein lipase activity (T-LPL) (LPL + HTGL) of the GAG-PS group at 10 weeks was higher than that of the cholesterol-diet group. These elevated T-LPL levels were mainly due to an increase in the LPL from peripheral tissues. ADP-induced platelet aggregability of the GAG-PS group significantly decreased at 10 weeks when compared to the cholesterol-diet group, and antithrombin-III activity of the GAG-PS group was inversely increased when compared to the cholesterol-diet group. Although there were no differences in aortic levels of total cholesterol and uronic acid between the GAG-PS group and the cholesterol-diet group, the surface involvement of the aorta in the GAG-PS group was significantly lower than that in the cholesterol-diet group. The aortic levels of free cholesterol, hydroxyproline and calcium of the GAG-PS group were significantly decreased when compared to the cholesterol-diet group. These findings suggest that GAG-PS has antiatherosclerotic effects.

Animals

Comparison of serum lipid values in variant angina pectoris and fixed coronary artery disease with normal subjects.

Lipid and apolipoprotein (apo) levels in patients with variant angina were examined and compared with patients with coronary artery disease (CAD) and normal subjects (control). Cholesterol and triglyceride levels in plasma, lipoprotein fractions and several apolipoproteins were measured in 108 men (90 of whom had undergone coronary angiography): 22 had variant angina, 56 had fixed CAD (effort angina and old myocardial infarction) and 30 were normal subjects. Patients with variant angina showed more severe atherosclerotic lesions than the control group, but less severe lesions than the patients with fixed CAD. In comparison with lipid and apolipoprotein, high density lipoprotein cholesterol, apo AI and apo AII decreased significantly in control, variant angina and fixed CAD groups, respectively. Additionally, stepwise discriminant analysis revealed that apo AI was the best discriminator among the 3 groups or between variant angina or fixed CAD and the control group. Variant angina and fixed CAD patients could be discriminated from the control subjects by an apo AI level of 135 and 126 mg/dl, with 71% (p less than 0.025) and 73% (p less than 0.005) accuracy, respectively. By these criteria 77% of the patients with variant angina and 73% of the patients with fixed CAD were precisely discriminated. Discrimination between variant angina and fixed CAD patients, however, was not practical, even if the best discriminator was used. Thus, the apo AI level is useful in discriminating patients with variant angina and fixed CAD from normal subjects. Therefore, symptomatic patients with low apo AI levels should be aggressively examined.

Adult

Effects of a new alpha 1-blocker, bunazosin hydrochloride, on plasma lipid components in hypertensive patients with hypercholesterolemia.

Oral bunazosin hydrochloride, a new alpha 1-blocker, for 12 weeks was given to ten outpatients diagnosed as having essential hypertension associated with hypercholesterolemia. High-density lipoprotein (HDL) triglyceride, HDL3 cholesterol, and apolipoprotein E levels were significantly decreased by bunazosin treatment. The decrease in HDL triglycerides was a result of the decrease in HDL3 triglyceride levels. There were no significant changes in the other components. The ratio of cholesterol to triglycerides in the low-density lipoprotein (LDL) and HDL fractions was increased significantly after bunazosin treatment. Furthermore, the ratio of HDL2 cholesterol to HDL3 cholesterol after bunazosin treatment was significantly higher than before treatment. The results suggest that the catabolism of triglycerides in lipoprotein and the reduction in tissue cholesterol increase, and that bunazosin hydrochloride does not adversely affect the lipid component in hypertensive patients with hypercholesterolemia.

Adrenergic alpha-Antagonists

[The analysis of the result of the medical examination of inhabitants in the Honjoh area--the relationship between the abnormality in the electrocardiogram and blood pressure, age].

Blood pressure and electrocardiographic findings obtained from the medical screening of citizen (total 834) in Honjyo area, which was done in University of Occupational and Environmental Health Hospital from 1979 to 1983, were analysed. The findings of electrocardiograms (ECG) were classified according to Minnesota code. In this study, the prevalence of Hypertension, classified by the criteria of WHO, showed 12.2% in total, which was lesser than that of Japanese (23.1%). On the electrocardiographic findings, left ventricular hypertrophy and myocardial abnormalities in hypertensive group were significantly higher when compared to those of normotensive group. The ratio of abnormal ECG group was slightly higher than that of Japanese. Especially, the prevalences of arrhythmia and ST elevation were significantly higher than those of Japanese. And there were significant correlations between LVH and blood pressure, and between the abnormalities of conduction system and age. However, it is very difficult to conclude whether these findings are characteristic feature in Honjyo area or not. In order to clarify the characteristic features of cardiovascular systemic abnormalities in Honjyo area, the analysis of more cases would be needed.

Adult

Hypocholesterolemic effect of soybean protein in rats and mice after peptic digestion.

Analyses of gastrointestinal contents of rats fed soybean protein isolate and casein showed that soybean protein was readily digested in the stomach but migrated slowly in the small intestine. The soluble fraction of the stomach contents of rats fed soybean protein was separated by gel-filtration on Sephadex G25 into large and small molecular fractions, the latter was not found in rats fed casein. The formation of low-molecular-weight peptides was pH dependent, and analogous peptides were produced by pepsin in vitro not only from soybean protein but also from casein. In rats the peptic digest of soybean protein was found to be as hypocholesterolemic as intact soybean protein. Meanwhile, the cholesterol-lowering action of the large molecular fraction of the peptic digest tended to be greater than that of the small molecular fraction in mice. These observations suggest a significant role of peptic digestion in the cholesterol-lowering action of soybean protein.

Amino Acids