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F Mainard

Publications and source records attributed to F Mainard.

At least 19 recordsLinked to original sources
PubMed1998

Demographic and cardiovascular risk factors in relation to antioxidant status: the EVA Study.

The aim of the study was to examine the determinants of blood antioxidant indicators on a large sample. Levels of plasma selenium and carotenoids, vitamin E in red blood cells, and thiobarbituric acid reactive substances (TBARS) were determined. The cross-sectional relationships between these markers and demographic and cardiovascular risk factors were examined in participants of the EVA study, a cohort of 1389 men and women, aged 59-71 years. Multivariable regression models including demographic (age, sex, socio-economic level), lifestyle (alcohol, tobacco), clinical and metabolic (lipids, glycemia) factors were used. Women had higher levels of plasma carotenoids, TBARS and red blood cell vitamin E. Cholesterol levels were positively associated to lipid-soluble vitamins, selenium and TBARS. Use of lipid-lowering drugs was positively associated with selenium and vitamin E and negatively with carotenoids. Body mass index was the strongest determinant of plasma carotenoids. Education and income levels were positively associated with selenium and total carotenoids. Tobacco consumption was negatively associated with red blood cell vitamin E, whereas alcohol consumption was positively associated with TBARS. This study emphasizes the respective place of the various determinants of antioxidant status. When considering tissue antioxidant indicators, analyses should take into account not only the metabolic parameters but also socio-economic factors and the subject's life style.

Aged↗
PubMed1997

Lipoprotein (a) phenotype distribution in a population of bypass patients and its influence on lipoprotein (a) concentration.

A case control study was undertaken to compare the distribution of apolipoprotein (a) phenotypes in patients suffering from atherosclerosis and undergoing coronary bypass surgery with the distribution observed in adequately selected controls. Cases differed from controls for triglycerides (1.90 +/- 0.88 mmol l-1 and 1.16 +/- 0.79 mmol l-1, P < 0.0001, respectively), HDL cholesterol (1.15 +/- 0.34 mmol l-1 and 1.69 +/- 0.42 mmol l-1, P < 0.0001, respectively), apolipoprotein AI (1.31 +/- 0.24 g l-1 and 1.70 +/- 0.29 g l-1, P < 0.0001, respectively) and lipoprotein a (Lp(a)) (0.32 +/- 0.30 g l-1 and 0.19 +/- 0.20 g l-1, P < 0.0001, respectively). The apolipoprotein (a) phenotypes were distributed differently in cases and controls (chi 2 = 25.26, P < 0.0001) with a lower percentage of isoforms of larger size and a higher percentage of isoforms of smaller size in patients. The Lp(a) concentration remained significantly higher in patients than in controls for most of the phenotypes, suggesting that both a high Lp(a) concentration and a different apolipoprotein (a) size distribution could be involved in the development of atherosclerosis in this population. In addition, patients exhibiting the highest Lp(a) concentrations had higher levels of LDL cholesterol and apolipoprotein B than patients exhibiting the lowest Lp(a) concentrations. This feature was not observed in controls. By contrast, controls with the highest Lp(a) concentration had significantly higher triglyceride levels than controls with the lowest Lp(a) concentration. This feature was not observed in patients. Our results indicate that patients undergoing bypass surgery have higher Lp(a) concentrations than controls, this increase being not completely explained by the difference in apolipoprotein (a) phenotype distribution. The high Lp(a) concentration seems to be associated with different lipid profiles in patients than in controls.

Adult↗
PubMed1997

Lipid peroxidation level and antioxidant micronutrient status in a pre-aging population; correlation with chronic disease prevalence in a French epidemiological study (Nantes, France).

OBJECTIVE: The general objective of the Etude du Viellissement Arterial (EVA) program is to follow vascular aging and the decline in cognitive functions at the cerebrovascular level longitudinally over a 4-year period. One of the specific objectives of this EVA study is to examine epidemiologically the relationship between the markers of oxidative stress (lipid peroxidation), the antioxidant micronutrient status (particularly of selenium, vitamin E, and the carotenoids) and the prevalence of chronic disorders occurring during the pre-aging period. METHODS: 1389 subjects aged from 59 to 71 years were studied. RESULTS: The concentration of plasma lipid peroxides was higher than in young adults (2.91 +/- 0.38, men; 2.97 +/- 0.40, women (mumol/l). On the other hand, plasma Se (1.09 +/- 0.21, men; 1.10 +/- 0.19, women (mumol/l)), erythrocyte vitamin E (5.32 +/- 1.29, men; 5.52 +/- 1.28, women (mumol/l)), and total plasma carotenoids (2.19 +/- 0.98, men; 3.07 +/- 1.33, women (mumol/l)) were comparable to values in young adults. In our cohort, 40% of subjects had unremarkable medical histories. The disorders most often encountered were lipemia (29.8% of men, 36.1% of women), and hypertension (28.9% of men, 30.4% of women). CONCLUSION: Se and vitamin E levels were raised in cases of lipemia, especially in those treated with fibrates. The mechanism of the increase is unknown. In hypertensives and diabetics, there was a decrease in total carotenoids associated with increased peroxidative risk.

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PubMed1996

Relation of intima-media thickness to atherosclerotic plaques in carotid arteries. The Vascular Aging (EVA) Study.

This study examined the relation between arterial wall thickness and local atherosclerosis in the carotid arteries (CAs) and their specific risk factors. B-mode ultrasonography of the CAs was performed in a cohort of 516 men and 756 women aged 59 to 71 years who had been recruited for the European Vascular Aging Study. Ultrasound examination included measurement of intima-media thickness of the common CA (CCA) and the sites of plaque in the internal CA and bifurcations. Significant associations between increases in CCA intima-media thickness and both the presence and severity of atherosclerotic plaque were found in men and women. Examination of specific risk factors for increases in CCA intima-media thickness in the presence of plaque showed that, after adjustment for sex, both ultrasound measurements were independently related to age, body mass index, hypertension, and ever smoking (versus never smoking). Diabetes and current smoking were associated with intima-media thickness only, whereas hypercholesterolemia was related to plaque only. However, when subjects who were taking lipid-lowering drugs were excluded, lipoproteins and apolipoproteins were more consistently related to intima-media thickness than to plaque. In subjects free from any antihypertensive treatment, both intima-media thickness and plaques were independently associated with systolic blood pressure. After adjustment for sex and other risk factors, the odds ratio for having at least one plaque associated with a 0.10-mm increase in CCA intima-media thickness was 1.18 (95% confidence interval, 1.05 to 1.32). In this relatively aged population, increases in intima-media thickness as measured in the CCAs were clearly related to locally detected atherosclerosis and known risk factors for atherosclerosis. Longitudinal studies are needed to clarify the role of arterial wall thickening in the atherosclerotic process.

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PubMed1996

[HDL-cholesterol or apolipoprotein AI: which parameter to choose?].

The French Consensus for cholesterol, established by ARCOL in 1989, recommends the use of HDL-cholesterol and apolipoprotein AI as additional parameters. The present study was undertaken to establish the correlation between these two parameters and to determine the limit value for apolipoprotein AI, based on the recommended limit of 0.90 mmol/L for HDL-cholesterol established by ARCOL. The correlation between HDL-cholesterol analysed by precipitation, and apolipoprotein AI analysed by immunonephelemetry on the day of blood drawing, determined on 1980 samples, raised a r value of 0.89. Using the regression line equation (y = 0.602 x + 0.629), the apolipoprotein AI value corresponding to the recommended HDL-cholesterol limit (0.90 mmol/L) was found to be 1.17 g/L, while the limit value established by ARCOL was 1.20 g/L. Using the HDL-cholesterol value of 0.90 mmol/L, the population was divided into a high risk group and a low risk group. With the limit value of 1.20 g/L for apolipoprotein AI, 89.2% of the subjects would be correctly classified. This percentage would be raised to 90.65% using the value (1.17 g/L) established in our study. Our conclusion is that apolipoprotein AI as well as HDL-cholesterol represent good markers for atherosclerosis in the clinical practice. The advantage of HDL-cholesterol is that the determination of this parameter allows the calculation of LDL-cholesterol which is used in all consensus, while the advantage of apolipoprotein AI is that it may be analysed automatically.

Apolipoprotein A-I↗
PubMed1994

Comparative study of risk factors in patients undergoing coronary or femoropopliteal artery bypass grafting.

OBJECTIVE: To compare risk factors in two populations of patients with advanced atheroma requiring coronary or femoropopliteal artery bypass grafting to try to account for the different localisations of vascular disease. DESIGN: Cross sectional epidemiological study. SETTING: Cardiovascular surgery department of a university hospital. SUBJECTS: 464 men (mean age 59.25 (SD 8.57) years) undergoing coronary artery bypass grafting; 74 men (mean age 56.28 (13.3) years) undergoing femoropopliteal artery bypass grafting; and 204 control men (mean age 45.07 (6.59) years) who had been recruited in a preventive medicine department. INTERVENTIONS: Blood samples were drawn 24 hours before surgery. METHODS: Lipid and lipoprotein concentrations were measured for each patient and with adjustment for age were compared by analysis of covariance. The main risk factors (smoking, arterial hypertension, obesity, and diabetes) were determined by a standardised history, and the chi 2 test was used to compare the results in the two patient groups. Pairwise comparisons between the three populations were performed by logistic discriminant analysis. RESULTS: Both patient groups showed a significant rise in triglyceride concentration and in the ratio of total cholesterol to high density lipoprotein cholesterol (R1) and a drop in apolipoprotein AI and high density lipoprotein cholesterol concentrations. Disturbances were greater in patients undergoing coronary artery bypass grafting than in those undergoing femoropopliteal artery bypass grafting for the R1 ratio, apolipoprotein B concentration, and the ratio of apolipoprotein AI to apolipoprotein B (R2). A higher proportion of smokers was found in the femoropopliteal bypass group than in the coronary bypass group, whereas were often obese. Logistic discriminant analysis with adjustment for age and with the coronary bypass as the reference group selected three factors: smoking, the R2 ratio, and obesity. CONCLUSION: Disturbances in lipid and apoprotein concentrations varied with respect to bypass site. Other risk factors played a part in accelerating the atherogenic process, especially smoking in patients undergoing femoropopliteal artery bypass grafting and, to a lesser degree, obesity in patients undergoing coronary artery bypass grafting.

Adult↗
PubMed1992

[Serum myoglobin: evaluation of two immunolatex methods. Comparison with a radioimmunoassay method].

Latex immunoturbidimetric (ITA) and immunonephelemetric (INA) assays, were evaluated and compared to a radioimmunological assay (RIA) for the determination of serum myoglobin. Within-run and between-run assays and accuracy and linearity studies gave satisfactory results, very similar to those of RIA. Results were closely correlated with those of RIA for 100 samples of up to 2,000 micrograms/l (correlation coefficients respectively 0.96 and 0.97 for ITA and INA). Reference values (150 men and 150 women; range 20-65 years) were determined and expressed in percentiles. It is concluded that the two latex immunologic assays facilitate laboratory myoglobin evaluation (no radioactive material, short performance time). ITA is more suitable for emergency analysis and INA is more convenient for serial analysis and particular samples (presence of hemoglobin or chylomicrons).

Adult↗
PubMed1990

Logistic discriminant analysis of lipids and apolipoproteins in a population of coronary bypass patients and the significance of apolipoproteins C-III and E.

The lipid and apolipoprotein states of 74 men (mean age 49.96 +/- 5.9 years) were studied 24 h before coronary bypass surgery and their results were compared with those of a control group of 78 men (mean age 48.88 +/- 5.41 years). Apolipoproteins C-III (apo C-III) and E (apo E) were determined in particles with (LpB) and without (nonLpB) apo B separated using a concanavalin A reagent. Apo C-III was significantly increased in LpB particles (P less than 0.001), and apo E in LpB (P less than 0.001) and nonLpB (P less than 0.001) particles. The significant variables selected in logistic discriminant stepwise analysis were total cholesterol/HDL-cholesterol, apo E-nonLpB and apo C-III-LpB. This last parameter, which is more discriminant than triglycerides, provides a more specific indication of dyslipoproteinemia in coronary bypass patients; in association with the other two variables, it significantly improved the percentage of correctly classified individuals.

Adult↗
PubMed1990

[Use of 6 serum pools in standardization of the determination of apolipoproteins AI and B in the human serum].

The proliferation of commercial immunoassays for the determination of apolipoproteins AI and B as parameters of risk for coronary heart disease and the discordance between the values obtained with the systems have made more urgent than ever the need for standardization of these assays. The authors report here the results of a collaborative study on the standardization of the values between the "Comité Française de Coordination des Recherches sur l'Athérosclérose et le Cholestérol (ARCOL)" and 13 Companies providing 15 different analytical systems. The results show that standardized measurements are not possible using a "consensus international standard" and that the major problem is related to the enormous variability of the analytical systems. In contrast, the present study demonstrates that six different serum pools containing increasing amounts of apolipoproteins AI and B can be used to generate a common reference curve which permits calibration of all immunoassays and standardization of results.

Apolipoprotein A-I↗
PubMed1990

Study of lipoprotein particles LpAI and LpAI:AII in patients before coronary bypass surgery.

Lipids, apolipoproteins, and LpAI and LpAI:AII particles were studied in 43 men (mean age 51, SD 7, years) 24 h before their coronary bypass surgery and in 54 control men (mean age 46 SD 9, years). LpAI and LpAI:AII were analyzed by electroimmunodiffusion and by a noncompetitive enzyme-linked immunoassay, respectively. Concentrations of LpAI and LpAI:AII in the bypass patients were significantly lower (P less than 0.001) than those in the controls. Apolipoprotein AI was significantly correlated with LpAI (P less than 0.001) and LpAI:AII (P less than 0.01) in controls, but only with LpAI:AII (P less than 0.001) in bypass patients. Discriminant analysis between controls and patients showed apolipoprotein AI to be the most powerful discriminant factor; the addition of LpAI and LpAI:AII did not improve discriminant power. We conclude that the determination of LpAI and LpAI:AII particles reflects metabolic disorders in patients but does not significantly influence the discrimination of such patients into risk groups.

Apolipoproteins A↗
PubMed1988

[Lipid evaluation in cerebral infarction in its early phase and in the 4th month. Practical consequences].

Plasma lipid values studied in 30 subjects with stroke at days 1, 2 and 4 of the early phase indicated a significant decrease in total cholesterol, HDL-cholesterol and apolipoprotein A1 from day 1 to 4. However, there was no significant difference between values at day 1 and during the 4th month of convalescence. Since some patients admitted to hospital are never followed up later in a hospital environment, it would seem advisable, for practical purposes, to perform plasma lipid analysis on the first day of admission.

Adult↗
PubMed1988

Variations in lipoproteins, hormones and blood glucose during the early acute phase of myocardial infarction.

This study reports on 22 patients (18 men, 4 women), 45-83-year-old admitted to hospital less than 24 h after the first clinical signs of myocardial infarction. Lipids, lipoproteins, serum insulin and growth hormone, urinary cortisol and vanillylmandelic acid and blood glucose were analysed on the day of admission (day 1) and on days 2, 4 and 8 of the acute phase. Results for lipoproteins generally confirm those of earlier studies: lowered total cholesterol (day 1-8), LDL-cholesterol (day 1-2), HDL-cholesterol (day 2-8), LDL apo B (day 1-2) and apo A-1 (day 1-8). There was no significant correlation between stress hormone and plasma lipoprotein alterations. Blood glucose decreased progressively (P less than 0.05) between day 1 and day 8. Glucose value at day 1 correlated significantly with nonesterified fatty acids, total cholesterol and LDL constituents, but not with HDL-cholesterol and apo A-1. Metabolic disturbances modifying blood glucose thus might be involved in LDL changes, whereas other processes govern HDL changes.

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