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1.
Antioxidants are crucial components of fruit/vegetable rich diets preventing cardiovascular disease (CVD) and cancer: plasma vitamins C, E, carotenoids from diet correlate prevalence of CVD and cancer inversely, low levels predict an increased risk of individuals which is potentiated by combined inadequacy (e.g., vitamins C + E, C + carotene, A + carotene); self-prescribed rectification of vitamins C and E at adequacy of other micronutrients reduce forthcoming CVD, of vitamins A, C, E, carotene and conutrients also cancer; randomized exclusive supplementation of beta-carotene +/- vitamin A or E lack benefits except prostate cancer reduction by vitamin E, and overall cancer reduction by selenium; randomized intervention with synchronous rectification of vitamins A + C + E + B + minerals reduces CVD and counteracts precancerous lesions; high vitamin E supplements reveal potentials in secondary CVD prevention. Plasma values desirable for primary prevention: > or = 30 mumol/l lipid-standardized vitamin E (alpha-tocopherol/cholesterol > or = 5.0 mumol/mmol); > or = 50 mumol/l vitamin C aiming at vitamin C/vitamin E ratio > 1.3-1.5; > or = 0.4 mumol/l beta- (> or = 0.5 mumol/l alpha+ beta-) carotene. CONCLUSIONS: In CVD vitamin E acts as first risk discriminator, vitamin C as second one; optimal health requires synchronously optimized vitamins C + E, A, carotenoids and vegetable conutrients.  相似文献   

2.
BACKGROUND: Oxidized low-density lipoprotein is involved in the pathogenesis of atherosclerosis. In epidemiological studies antioxidants have been inversely related with coronary heart disease. Findings from controlled trials are inconclusive. METHODS: We studied the primary preventive effect of vitamin E (alpha tocopherol) and beta carotene supplementation on major coronary events in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, a controlled trial undertaken primarily to examine the effects of these agents on cancer. A total of 27 271 Finnish male smokers aged 50 to 69 years with no history of myocardial infarction were randomly assigned to receive vitamin E (50 mg), beta carotene (20 mg), both agents, or placebo daily for 5 to 8 years (median, 6.1 years). The end point was the first major coronary event, either nonfatal myocardial infarction (surviving at least 28 days; n = 1204) or fatal coronary heart disease (n = 907). RESULTS: The incidence of primary major coronary events decreased 4% (95% confidence interval, -12% to 4%) among recipients of vitamin E and increased 1% (95% confidence interval, -7% to 10%) among recipients of beta carotene compared with the respective nonrecipients. Neither agent affected the incidence of nonfatal myocardial infarction. Supplementation with vitamin E decreased the incidence of fatal coronary heart disease by 8% (95% confidence interval, -19% to 5%), but beta carotene had no effect on this end point. CONCLUSIONS: Supplementation with a small dose of vitamin E has only marginal effect on the incidence of fatal coronary heart disease in male smokers with no history of myocardial infarction, but no influence on nonfatal myocardial infarction. Supplementation with beta carotene has no primary preventive effect on major coronary events.  相似文献   

3.
This study describes the design, methodologic features, and baseline characteristics of an open-label randomized trial to determine whether aggressive lipid-lowering therapy with atorvastatin is an alternative to angioplasty or other catheter-based revascularization procedures in patients with significant coronary artery disease. Three-hundred forty-one patients with low-density lipoprotein (LDL) cholesterol > or = 115 mg/dl and > or = 1 defined narrowing of a major coronary artery were randomized to atorvastatin or the indicated catheter-based revascularization and conventional care (including lipid-lowering therapy if prescribed). Ischemic events are tracked for 18 months. The primary efficacy parameter is the incidence of an ischemic event, defined as 1 of the following: cardiovascular death, cardiac arrest, nonfatal myocardial infarction, the need for coronary bypass grafting or angioplasty, cerebrovascular accident, and worsening angina verified by objective evidence requiring hospitalization (including unstable angina).  相似文献   

4.
The Heart and Estrogen/progestin Replacement Study (HERS) is a randomized, double-blind, placebo-controlled trial designed to test the efficacy and safety of estrogen plus progestin therapy for prevention of recurrent coronary heart disease (CHD) events in women. The participants are postmenopausal women with a uterus and with CHD as evidenced by prior myocardial infarction, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, or other mechanical revascularization or at least 50% occlusion of a major coronary artery. Between February 1993 and September 1994, 20 HERS centers recruited and randomized 2763 women. Participants ranged in age from 44 to 79 years, with a mean age of 66.7 (SD 6.7) years. Most participants were white (89%), married (57%), and had completed high school or some college (80%). As expected, the prevalence of coronary risk factors was high: 62% were past or current smokers, 59% had hypertension, 90% had serum LDL-cholesterol of 100 mg/dL or higher, and 23% had diabetes. Each woman was randomly assigned to receive one tablet containing 0.625 mg conjugated estrogens plus 2.5 mg medroxyprogesterone acetate daily or an identical placebo. Participants will be evaluated every 4 months for an average of 4.2 years for the occurrence of CHD events (CHD death and nonfatal myocardial infarction). We will also assess other major CHD endpoints, including revascularization and hospitalization for unstable angina. The primary analysis will compare the rate of CHD events in women assigned to active treatment with the rate in those assigned to placebo. The trial was designed to have power greater than 90% to detect a 35% reduction in the incidence of CHD events, assuming a 50% lag in effect for 2 years and a 5% annual event rate in the placebo group. The design, analysis, and conduct of the study are controlled by the Steering Committee of Principal Investigators and coordinated at the University of California, San Francisco. HERS is the largest trial of any intervention to reduce the risk of recurrent CHD events in women with heart disease and is the first controlled trial to seek evidence of the efficacy and safety of postmenopausal hormone therapy to prevent recurrent CHD events.  相似文献   

5.
BACKGROUND: Epidemiological data suggest that the intake of antioxidants such as alpha-tocopherol (vitamin E) and beta-carotene has an inverse correlation with the incidence of coronary heart disease. The results from clinical trials of antioxidant supplementation in people with known coronary heart disease are inconclusive. METHODS: We studied the frequency of major coronary events in 1862 men enrolled in the alpha-tocopherol beta-carotene Cancer Prevention Study (smokers aged between 50 and 69 years) who had a previous myocardial infarction. In this randomised, double-blind. placebo-controlled study, men had received dietary supplements of alpha-tocopherol (50 mg/day), beta-carotene (20 mg/day), both, or placebo. The median follow-up was 5.3 years. The endpoint of this substudy was the first major coronary event after randomisation. Analyses were by intention to treat. FINDINGS: 424 major coronary events (non-fatal myocardial infarction and fatal coronary heart disease) occurred during follow-up. There were no significant differences in the number of major coronary events between any supplementation group and the placebo group (alpha-tocopherol 94/466; beta-carotene 113/461; alpha-tocopherol and beta-carotene 123/497; placebo 94/438 [log-rank test, p = 0.25]). There were significantly more deaths from fatal coronary heart disease in the beta-carotene (74/461, multivariate-adjusted relative risk 1.75 [95% CI 1.16-2.64], p = 0.007) and combined alpha-tocopherol and beta-carotene groups (67/497, relative risk 1.58 [1.05-2.40], p = 0.03) than in the placebo group (39/438), but there was no significant increase in the alpha-tocopherol supplementation group (54/466, relative risk 1.33 [0.86-2.05], p = 0.20). INTERPRETATION: The proportion of major coronary events in men with a previous myocardial infarction who smoke was not decreased with either alpha-tocopherol or beta-carotene supplements. In fact, the risk of fatal coronary heart disease increased in the groups that received either beta-carotene or the combination of alpha-tocopherol and beta-carotene; there was a non-significant trend of increased deaths in the alpha-tocopherol group. We do not recommend the use of alpha-tocopherol or beta-carotene supplements in this group of patients.  相似文献   

6.
An increasing body of evidence suggests that beside hypercholesterolemia peroxidative processes and natural antioxidant defence system play important role in the development of atherosclerosis. Our earlier investigation showed the increased intensity of the peroxidative processes in the course of the acute myocardial infarction and unsatisfactory tocopherol, ascorbic acid and retinol status. The purpose of the present study was the evaluation of the effect of antioxidant vitamins supplementation by the period of 21 days on the peroxidative processes in patients after heart attack or after "bypass" admitted to the cardiological rehabilitation centre. Daily oral supplementation with vitamin C, E and beta-carotene decreased significantly plasma lipid peroxide concentration (TBARS). The highest drop in TBARS activity was found in the group after bypass. No significant effect of vitamin supplementation was observed on antioxidant enzymes activity.  相似文献   

7.
The SUpplementation en VItamines et Minéraux AntioXydants (SU.VI.MAX) Study is a randomized, double-blind, placebo-controlled, primary-prevention trial designed to test the efficacy of daily supplementation with antioxidant vitamins (vitamin C, 120 mg; vitamin E, 30 mg; and beta-carotene, 6 mg) and minerals (selenium, 100 microg; and zinc, 20 mg) at nutrition-level doses (one to three times the daily recommended dietary allowances) in reducing several major health problems in industrialized countries, especially the main causes of premature death, cancers and cardiovascular diseases. The present report describes the design, implementation, and baseline characteristics of participants in this 8-year cohort study, which started in 1994 in France; 12,735 eligible subjects (women aged 35-60, and men aged 45-60) were included in 1994 and will be followed for 8 years. Participants undergo a yearly visit consisting, every other year, of either biological sampling or clinical examination. They also regularly provide information on health events and dietary intake by filling out computerized questionnaires using the Minitel Telematic Network. Data on baseline characteristics of the participants suggest that the present sample is close to the national population in terms of geographic density, socioeconomic status, and the distribution of various major risk factors for the diseases under study. The choice of the study population should allow the results of this trial to apply to adult populations of both sexes in France and other industrialized countries.  相似文献   

8.
A randomized double-blind trial was performed in order to assess the efficacity of differing combinations of antioxidant nutrients on biochemical parameters of vitamin and trace element status, immunological parameters and free radical metabolism in elderly long term hospitalized subjects. A total of 756 institutionalized elderly subjects were recruited in 26 nursing homes in different areas of France. Four groups were constituted, receiving daily, for 1 year, either vitamins (beta-carotene, 6 mg; vitamin C, 120 mg; and vitamin E, 15 mg), trace elements (zinc, 20 mg and selenium, 100 micrograms), trace elements associated with vitamins, or a placebo. Biochemical indicators of trace elements and vitamin status and free radical parameters were measured before and after 6 months and 1 year of supplementation. Some immunological markers were investigated initially and after 6 months of supplementation on a subsample of 134 subjects. Mean plasma levels of alpha-tocopherol, gamma-tocopherol, vitamin C, alpha-carotene, beta-carotene and copper increased significantly after 6 months of supplementation in groups receiving vitamins alone or associated with trace elements. Serum selenium concentrations were significantly increased at 6 months of supplementation, and serum zinc only after one year in the trace element groups. Serum lycopene levels were significantly decreased by trace element supplementation. A significant increase in Se-glutathione peroxidase (GPx) levels was observed in groups receiving trace elements alone or associated with vitamins. No effect was noted on superoxide dismutase (SOD) activity or TBARs production. No effect of supplementation was found for in vitro lymphocyte proliferative responses or most lymphocyte subsets, except for a significantly lower percentage of CD2 subsets observed in groups receiving mineral supplementation either alone or associated with vitamins. A significant difference in CD19 subsets was found in groups receiving trace elements. Mean IL-1 production was significantly higher after 6 months of supplementation in the vitamin groups.  相似文献   

9.
This cross-sectional survey was conducted in 20 randomly selected streets in Moradbad city in North India to determine the association of magnesium and antioxidant vitamins with risk of ageing. There were 595 subjects (314 males, 281 females) between 50-84 years of age inclusive. The overall prevalence of hypo-magnesemia was 11.8 per cent (n = 60) with a prevalence of 13.2 per cent (n = 33) in males and 10.6 per cent (n = 27) in females. The prevalence of hypomagnesemia showed significant declining trend in the concentration of serum magnesium, vitamin C, vitamin E and beta-carotene and a rising trend in lipid peroxides and diene conjugates with increase in age from 50-59 years to 70-84 years in both men and women. Multivariate logistic regression analysis showed that serum magnesium, vitamin C, vitamin E and beta-carotene were significant risk factors of ageing in both men and women. The findings suggest that some urban populations of India can benefit by consuming higher dietary magnesium, potassium and antioxidant vitamins for prevention of ageing.  相似文献   

10.
BACKGROUND: Epidemiologic studies have shown dietary antioxidants to be inversely correlated with ischemic heart disease. OBJECTIVE: We investigated whether dietary beta-carotene, vitamin C, and vitamin E were related to the risk of myocardial infarction (MI) in an elderly population. DESIGN: The study sample consisted of 4802 participants of the Rotterdam Study aged 55-95 y who were free of MI at baseline and for whom dietary data assessed by a semiquantitative food frequency questionnaire were available. During a 4-y follow-up period, 124 subjects had an MI. The association between energy-adjusted beta-carotene, vitamin C, and vitamin E intakes and risk of MI was examined by multivariate logistic regression. RESULTS: Risk of MI for the highest compared with the lowest tertile of beta-carotene intake was 0.55 (95% CI: 0.34, 0.83; P for trend = 0.013), adjusted for age, sex, body mass index, pack-years, income, education, alcohol intake, energy-adjusted intakes of vitamin C and E, and use of antioxidative vitamin supplements. When beta-carotene intakes from supplements were considered, the inverse relation with risk of MI was slightly more pronounced. Stratification by smoking status indicated that the association was most evident in current and former smokers. No association with risk of MI was observed for dietary vitamin C and vitamin E. CONCLUSION: The results of this observational study in the elderly population of the Rotterdam Study support the hypothesis that high dietary beta-carotene intakes may protect against cardiovascular disease. We did not observe an association between vitamin C or vitamin E and MI.  相似文献   

11.
This review summarizes the scientific evidence for a possible role of antioxidants in the prevention of coronary heart disease (CHD). Dietary antioxidants include vitamin E, vitamin C and beta-carotene, whereas selenium is an integral part of the antioxidant enzyme glutathione peroxidase. Experimental studies suggest that the oxidation of low-density lipoproteins (LDL) in the vessel wall plays an important role in the development of atherosclerotic lesions. The resistance of LDL to oxidation is increased by antioxidant supplementation, at least in vitro. Epidemiological studies have not demonstrated unequivocally that a high intake of antioxidants leads to a decreased risk of CHD. Studies on dietary intake and serum levels of antioxidants do point in the direction of a preventive effect of antioxidants, whereas the results of intervention studies are less conclusive. Beta-carotene supplementation is not associated with any decrease in CHD; high doses of vitamin E may be beneficial, but results from large trials are to be awaited. General preventive measures based on antioxidant supplementation are not yet justifiable.  相似文献   

12.
BACKGROUND: Although most previous studies have attempted to correlate plasma concentrations of vitamins with specific cardiovascular end points, metabolic considerations suggest that changes in myocardial tissue and storage organs may be better indicators of myocardial oxidative stress. METHODS AND RESULTS: Rats fed commercial chow or a diet enriched with vitamin E for 2 weeks were subjected to either a surgical myocardial infarction (MI) or a sham procedure. Rats were hemodynamically assessed 16 weeks after surgery, and their heart, liver, kidney, and plasma were analyzed for antioxidant vitamins E (tocopherol) and A (retinol and total retinyl esters). At 16 weeks, MI rats on a control diet showed depressed peak systolic and elevated diastolic pressures in both right and left ventricles compared with their sham controls. Plasma concentrations of vitamins E and A in MI rats were not different from sham controls fed the same diet. However, concentrations of vitamin E in left ventricle and liver and of vitamin A in liver (retinol) and kidney (retinyl esters) were decreased in rats with MI compared with the sham controls. Vitamin E supplementation improved hemodynamic function in rats with MI and increased plasma, myocardial, liver, and kidney concentrations of vitamin E. The vitamin E diet also prevented the loss of total retinyl esters from the kidney but not of retinol from the liver in MI rats. CONCLUSIONS: Dietary supplements of vitamin E can sustain better cardiac function subsequent to MI. Antioxidant vitamin levels in the myocardium or in storage organs and not in plasma may be better indicators of myocardial oxidative stress.  相似文献   

13.
BACKGROUND: Since the 1980s, clinical trial evidence has supported aspirin use in the secondary prevention of cardiovascular disease (CVD). AIM: To explore aspirin use among British men with known CVD in a population-based study. METHOD: Longitudinal study (British Regional Heart Study), in which subjects have been followed up for cardiovascular morbidity and mortality since 1978-1980. Aspirin use was assessed by questionnaires to study participants in November 1992 (Q92); cardiovascular diagnoses are based on general practice notifications to October 1992. A total of 5751 men aged 52-73 years (87% of survivors) completed questions on aspirin use. RESULTS: Overall, 547 men (9.5%) were taking aspirin daily, of whom 321 (59%) had documented CVD. Among men with pre-existing disease, 153 out of 345 (44%) men with myocardial infarction, 42 out of 109 (39%) with stroke, and 75 out of 247 (29%) with angina were taking aspirin daily. Among men with angina (54% versus 26%) or myocardial infarction (59% versus 42%), those who had undergone coronary artery bypass surgery (CABG) or angioplasty were more likely to be receiving aspirin. Higher rates of aspirin use were also found in those whose last major event occurred after January 1990 (47% versus 34%). There was no association between aspirin use and social class or region of residence. CONCLUSION: Despite strong evidence of its effectiveness, many patients with established CVD were not receiving aspirin. Daily aspirin treatment was less likely in men with less recent major CVD events and in those who had not received invasive treatment.  相似文献   

14.
The "SUpplementation en VItamines et MinérauxAntioXydants" (SU.VI.MAX) study is a randomized double-blind, placebo-controlled, primary prevention trial designed to test the efficacy of daily supplementation with antioxidant vitamins (vitamin C, 120 mg; vitamin E, 30 mg; and beta-carotene, 6 mg) and minerals (selenium, 100 micrograms; and zinc, 20 mg), at nutritional doses (one to three times the daily recommended dietary allowances), in reducing the frequency of major health problems in industrialized countries, and especially the main causes of premature death (cancers and cardiovascular diseases). The study involves 12,735 eligible subjects (women aged 35 to 60 years; men aged 45 to 60 years) included in 1994 in France. They will be followed up for 8 years. The objectives and the specific design of this intervention study are linked to its public health aim. The targeted population is the general population (not simply high-risk subjects) and the antioxidant agents tested are being administered at a level which is not pharmacologic and which may be attained by dietary intake of natural sources of these micronutrients and/or enriched foods. The amounts we are testing in the SU.VI.MAX study are those which, in observational studies have been associated with the lowest risk of diseases. This report presents the rationale and discusses the justification of the design, doses and combination of antioxidant micronutrients chosen in the SU.VI.MAX study.  相似文献   

15.
OBJECTIVE: To explore the association of supplementary and dietary vitamin E and C intake with the progression of coronary artery disease. DESIGN: A subgroup analysis of the on-trial antioxidant vitamin intake database acquired in the Cholesterol Lowering Atherosclerosis Study, a randomized, placebo-controlled, serial angiographic clinical trial evaluating the risk and benefit of colestipol-niacin on coronary artery disease progression. SETTING: Community- and university-based cardiac catheterization laboratories. SUBJECTS: A total of 156 men aged 40 to 59 years with previous coronary artery bypass graft surgery. INTERVENTION: Supplementary and dietary vitamin E and C intake (nonrandomized) in association with cholesterol-lowering diet and either colestipol-niacin or placebo (randomized). OUTCOME: Change per subject in the percentage of vessel diameter obstructed because of stenosis (%S) determined by quantitative coronary angiography after 2 years of randomized therapy on all lesions, mild/moderate lesions (< 50%S), and severe lesions (> or = 50%S). RESULTS: Overall, subjects with supplementary vitamin E intake of 100 IU per day or greater demonstrated less coronary artery lesion progression than did subjects with supplementary vitamin E intake less than 100 IU per day for all lesions (P = .04) and for mild/moderate lesions (P = .01). Within the drug group, benefit of supplementary vitamin E intake was found for all lesions (P = .02) and mild/moderate lesions (P = .01). Within the placebo group, benefit of supplementary vitamin E intake was not found. No benefit was found for use of supplementary vitamin C exclusively or in conjunction with supplementary vitamin E, use of multivitamins, or increased dietary intake of vitamin E or vitamin C. CONCLUSIONS: These results indicate an association between supplementary vitamin E intake and angiographically demonstrated reduction in coronary artery lesion progression. Verification from carefully designed, randomized, serial arterial imaging end point trials is needed.  相似文献   

16.
Oxidation of low-density lipoprotein (LDL) probably plays an important part in atherosclerosis. Vitamin E (alpha-tocopherol) is a potent antioxidant carried in LDL. It increases the resistance of LDL to oxidation, thereby, among other things, inhibiting foam cell formation and proliferation of smooth muscle cells. Some animal experiments have indicated that vitamin E retards the development of atherosclerotic lesions. Observational studies (case-control and cohort) have shown that long-term treatment with vitamin E is associated with lower incidence of coronary heart disease in men and women alike. Randomisation to vitamin E in a large placebo controlled trial gave a nonsignificant reduction in mortality from ischemic heart disease. Although vitamin E seems to reduce the risk of coronary heart disease, randomised trials of adequate size are necessary in both secondary and primary prevention in order to test this. Such trials are in progress.  相似文献   

17.
BACKGROUND: Restenosis remains the major limitation of coronary angioplasty. Coronary stents have reduced the incidence of restenosis in selected patients with relatively large vessels. No strategies to date have demonstrated a beneficial effect in vessels < 3.0 mm in diameter. We have shown in the MultiVitamins and Probucol (MVP) Trial that probucol, a potent antioxidant, reduces restenosis after balloon angioplasty. The purpose of this study was to determine whether the benefit of probucol therapy is maintained in the subgroup of patients with smaller coronary vessels. METHODS AND RESULTS: We studied a subgroup of 189 patients included in the MVP trial who underwent successful balloon angioplasty of at least one coronary segment with a reference diameter < 3.0 mm. One month before angioplasty, patients were randomly assigned to one of four treatments: placebo, probucol (500 mg), multivitamins (beta-carotene 30000 IU, vitamin C 500 mg, and vitamin E 700 IU), or probucol plus multivitamins twice daily. The treatment was maintained until follow-up angiography was performed at 6 months. The mean reference diameter of this study population was 2.49+/-0.34 mm. Lumen loss was 0.12+/-0.34 mm for probucol, 0.25+/-0.43 mm for the combined treatment, 0.35+/-0.56 mm for vitamins, and 0.38+/-0.51 mm for placebo (P=.005 for probucol). Restenosis rates per segment were 20.0% for probucol, 28.6% for the combined treatment, 45.1% for vitamins, and 37.3% for placebo (P=.006 for probucol). CONCLUSIONS: Probucol reduces lumen loss and restenosis rate after balloon angioplasty in small coronary arteries.  相似文献   

18.
BACKGROUND: Although the short-term and long-term beneficial effects of early coronary revascularization by primary PTCA or thrombolytic therapy have been established for acute myocardial infarction, thrombolytic therapy >24 hours after the onset of acute myocardial infarction has not been shown to improve clinical outcome. The purpose of this study was to assess the effect of late revascularization by primary PTCA over a 5-year period. METHODS AND RESULTS: Eighty-three patients with initial Q-wave anterior myocardial infarction >24 hours after onset were randomized into a PTCA group (n=44) and a no-PTCA group (n=39). Long-term follow-up was conducted with regard to end points, which included cardiac death, nonfatal recurrence of myocardial infarction, and development of congestive heart failure. Left ventricular ejection fraction and regional wall motion at 6 months after myocardial infarction were similar in the 2 groups. Left ventricular end-diastolic and end-systolic volume indexes were significantly smaller in the PTCA group than in the no-PTCA group (P<0.0001). With cardiac events as end points, a 5-year Kaplan-Meier event-free survival analysis revealed that the no-PTCA group had a worse prognosis than the PTCA group (P<0.0001). Patency of the infarct-related artery, left ventricular ejection fraction, end-diastolic volume index, and end-systolic volume index were significantly associated with cardiac events by a Cox proportional hazards analysis (hazard ratios 0.120, 0.845, 1.065, and 1.164, respectively). CONCLUSIONS: In initial Q-wave anterior myocardial infarction, we conclude that even with late reperfusion, PTCA had beneficial effects on cardiac events over the 5-year period after myocardial infarction, with the prevention of left ventricular dilation after myocardial infarction being a possible mechanism.  相似文献   

19.
Augmentation of antioxidant defenses may help protect tissues against ischemia-reperfusion injury associated with operations involving cardiopulmonary bypass. In this study we examined the effect of pretreating patients with alpha-tocopherol (vitamin E) and ascorbic acid (vitamin C) or placebo on injury to the myocardium. Seventy-six subjects undergoing elective coronary artery bypass grafting participated in a prospective, double-blind, placebo-controlled randomized trial, receiving either placebo or both 750 IU dl-alpha-tocopherol per day for 7 to 10 days and 1 gm ascorbic acid 12 hours before the operation. Plasma alpha-tocopherol concentrations, raised fourfold by supplementation, fell by 70% after the operation in the supplemented group and to negligible levels in the placebo group. There were no significant differences between the groups with respect to release of creatine kinase MB isoenzyme over 72 hours, nor in the reduction of the myocardial perfusion defect determined by thallium 201 uptake. Electrocardiography provided no evidence of a benefit from antioxidant supplementation. Thus the supplementation regimen prevented the depletion of the primary lipid soluble antioxidant in plasma, but provided no measurable reduction in myocardial injury after the operation.  相似文献   

20.
OBJECTIVE: To examine the relation between nut consumption and risk of coronary heart disease in a cohort of women from the Nurses' Health Study. DESIGN: Prospective cohort study. SETTING: Nurses' Health Study. SUBJECTS: 86 016 women from 34 to 59 years of age without previously diagnosed coronary heart disease, stroke, or cancer at baseline in 1980. MAIN OUTCOME MEASURES: Major coronary heart disease including non-fatal myocardial infarction and fatal coronary heart disease. RESULTS: 1255 major coronary disease events (861 cases of non-fatal myocardial infarction and 394 cases of fatal coronary heart disease) occurred during 14 years of follow up. After adjusting for age, smoking, and other known risk factors for coronary heart disease, women who ate more than five units of nuts (one unit equivalent to 1 oz of nuts) a week (frequent consumption) had a significantly lower risk of total coronary heart disease (relative risk 0.65, 95% confidence interval 0.47 to 0.89, P for trend=0.0009) than women who never ate nuts or who ate less than one unit a month (rare consumption). The magnitude of risk reduction was similar for both fatal coronary heart disease (0.61, 0.35 to 1.05, P for trend=0.007) and non-fatal myocardial infarction (0.68, 0.47 to 1.00, P for trend=0.04). Further adjustment for intakes of dietary fats, fibre, vegetables, and fruits did not alter these results. The inverse association persisted in subgroups stratified by levels of smoking,use of alcohol, use of multivitamin and vitamin E supplements, body mass index, exercise, and intake of vegetables or fruits. CONCLUSIONS: Frequent nut consumption was associated with a reduced risk of both fatal coronary heart disease and non-fatal myocardial infarction. These data, and those from other epidemiological and clinical studies, support a role for nuts in reducing the risk of coronary heart disease.  相似文献   

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