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Biomedical subjects

B Herbeth

Publications and source records attributed to B Herbeth.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Updating of relative data on tocopherols in clinical biochemistry].

The working group on lipophilic vitamins of the FSBC has reviewed current knowledge in the field of tocopherols and tried to summarize the most important and recent aspects that may be useful to clinical practitioners. The molecular structure of tocopherols and tocotrienols, their biogenesis, their analysis in foods, their metabolism in humans, their measurement in biological fluids, and the organism's needs and dietary requirements are reviewed. Their main functions as antioxidants and free radical scavengers are described at the molecular, ultra-structural, cellular and organ levels. The interest of these vitamins in three pathologies in which oxidative-stress has been implicated (atherosclerosis, cancer, kidney failure) is discussed.

Arteriosclerosis↗
PubMed1993

Malondialdehyde adducts to, and fragmentation of, apolipoprotein B from human plasma.

Many recent in vitro experiments support the hypothesis that oxidatively modified low density lipoproteins (LDLs) could participate in atherogenesis. Oxidation of LDLs, especially derivatization by aldehydes originating from peroxidation of fatty acids and fragmentation of apolipoprotein (apo) B-100 which is their major apolipoprotein, probably occurs extravascularly and the presence of oxidized LDLs in the circulation is not well documented. Using electrophoresis and immunodetection techniques, we studied the structure of apo B and the presence of adducts of malondialdehyde (MDA) to this protein in LDLs from plasma of a limited population of five healthy subjects and nine patients with severe atherosclerosis. In the patient-derived LDLs, apo B appeared extensively fragmented, much more so than in those from the healthy subjects, although LDLs were isolated in all cases in the presence of antioxidants, protease inhibitors and antibiotics. Additionally, in all healthy subjects, we found a minor fragment of apo B-100, apo B-74, whereas the complementary peptide, apo B-26, was not detected; thus the presence of this minor form cannot be related to cleavage of apo B-100, either by proteolysis or by oxidation. We also present evidence that MDA adducts are present in circulating apo B and most of its fragments not only in atheromatous patients, but also in healthy subjects. Our results are consistent with the existence of oxidized LDLs in the human circulation. However, the role of non-oxidative phenomena in the structural modifications affecting apo B which are reported here cannot be excluded.

Adult↗
PubMed1993

Blood activities of antioxidant enzymes in alcoholics before and after withdrawal.

Since free radicals and peroxides seem to be involved in the toxicity of alcohol, several authors have examined the variations of blood activities of antioxidant enzymes in alcoholics, but published results are somewhat conflicting. In this study, erythrocyte (E) activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT), and plasma (P) activities of SOD and GPX were measured in 58 male alcoholics without evidence of severe liver disease before and after a 21-day weaning period, and in a control group of 78 healthy men. Before abstinence, E-SOD and E-GPX activities were, respectively, 6.8% and 13.0% lower in alcoholics than in controls (p < or = .05 and p < or = .01, respectively), whereas the slight increases of E-CAT, P-SOD and P-GPX were not statistically significant. After 21 days of abstinence, no change in activities of the erythrocyte enzymes was noticed; conversely, P-SOD activity was reduced by 8.3% (p < or = .01) and P-GPX by 23.3% (p < or = .001). Variations of blood antioxidant enzymes observed in patients were of limited amplitude and do not allow the use of either of them as markers of alcohol abuse.

Adult↗
PubMed1993

Does multivitamin supplementation prevent infections in healthy elderly subjects? A controlled trial.

We performed a double blind randomized study in order to assess the efficacy of a multivitamin supplement for the prevention of common infections in healthy elderly subjects. Non-institutionalized, independent subjects over 60 years of age, living in the Nevers area (central France) were recruited by announcements and randomly assigned to a treatment or a placebo group. The treatment or placebo tablets were to be taken daily for 4 months. The principal criterion of response was the incidence of infections, as recorded from a detailed questionnaire presented at entrance, in the middle (2 months) and at the end (4 months) of the study. Blood samples were taken at the entrance in the study and after two and four months in order to monitor vitamin status. No significant difference was found between the two groups for the incidence of infections. In fact the observed incidences during the two two-month periods were higher in the treatment (0.38 and 0.21) than in the placebo group (0.29 and 0.13). After two months and after four months of supplementation, blood vitamin indicators of the subjects were significantly higher in the treatment than in the placebo group for vitamins B1, B2, B6, E and folates (p < 0.001). The improvement of the vitamin C status was slightly higher in the treatment than in the placebo group. For vitamin A status, the evolution was similar in the two groups. In conclusion, short-term supplementation of healthy elderly subjects with the investigated supplement is not likely to afford a meaningful protection against common infections.

Aged↗
PubMed1993

The role of genetics in defining reference values and health status.

Since its establishment, the Center for Preventive Medicine in Vandoeuvre-les-Nancy, France, performed specific studies on healthy humans, and its approach was very useful for defining reference values. Prevention should extend its interest to chronic diseases. The majority of important adult disorders are partially genetically determined. Genetic markers are also useful as exclusion or as partition criteria in the production of reference values. Results are presented that were obtained for apolipoproteins E, B and AIV, frequencies of these polymorphisms in the Lorraine population, and relationships between these polymorphisms and lipid metabolism-related parameters. Health checkup centers, in particular those involved in family screening, are well suited for resembling many data concerning environmental factors: tobacco consumption, alimentation habits, or alcohol and drug consumption. Simultaneous determination of genetic markers could allow the determination of an individual's susceptibility or resistance to developing a disease and to prepare a preventive action.

Environmental Exposure↗
PubMed1992

Segregation analysis of height-adjusted weight with generation- and age-dependent effects: the Nancy Family Study.

A segregation analysis using a regressive model with generation- and age-dependent effects was applied to familial data of height-adjusted weight to investigate the major gene hypothesis. The sample included 629 nuclear families with 2,534 members volunteering for a free health check-up in the Preventive Medicine Center of Vandoeuvre-lès-Nancy, France. The familial correlations were 0.094 +/- 0.040 between spouses, 0.198 +/- 0.023 between parent and offspring, and 0.327 +/- 0.034 between siblings. The variability of the trait was higher in parents than in offspring. The most parsimonious genetic model indicated a codominant major effect increasing with age in childhood, then stabilizing in adulthood. The same data were analyzed using the classical mixed model, assuming equality of variances between parents and offspring, no resemblance between spouses, similar parent-offspring and sib-sib correlations, and identical effects in parents and offspring. This analysis indicated a recessive solution. In both analyses, mendelian transmission was rejected. However, the mixture of two distributions in the recessive model, instead of three in the codominant one, was less constraining with respect to the test of transmission probabilities, and the rejection of mendelian transmission was due to a single family in the recessive case, instead of several families in the codominant one. This could possibly explain why previous studies, all using the mixed model, found evidence for a recessive major gene. Although the major gene hypothesis cannot be definitely ruled out from our results, the mechanism appears more complex than the effect of one single gene.

Adolescent↗
PubMed1992

Age-related variations of enzymatic defenses against free radicals and peroxides.

Superoxide dismutase, glutathione peroxidase and catalase are the three main enzymatic systems of defense of the organism against free radicals and peroxides. A survey of the literature shows that no general tendency of evolution of these systems in aging emerges, even if some recent studies in humans demonstrate the existence of a concomitant decrease in most of the antioxidant enzymes in blood of the elderly. The study of the antioxidant systems and their interrelations in the elderly represents a large field of future investigations.

Adult↗
PubMed1991

Determinants of plasma retinol, beta-carotene, and alpha-tocopherol during adolescence.

The relationships of plasma retinol, retinol-binding protein (RBP), beta-carotene, and alpha-tocopherol with their potential determinants, plasma cholesterol and triglyceride, body fat, dietary intake, stages of pubertal development, and drugs, were examined in a French sample of 263 boys and 246 girls aged 10-15 y. By use of multiple-regression analysis, plasma retinol concentration was positively related to plasma cholesterol and triglyceride, sexual-maturation index, body fat, and being male. For plasma RBP the same predictors were identified. Plasma beta-carotene was positively related to plasma cholesterol and beta-carotene nutrient density and negatively related to body fat and plasma triglyceride. Three predictors of plasma alpha-tocopherol were identified: plasma cholesterol and vitamin E nutrient density, which were positively related to its concentration, and sexual-maturation index, which was negatively related. These results confirm that physiological developmental age should be considered in epidemiologic studies of plasma fat-soluble vitamins in adolescents.

Adipose Tissue↗
PubMed1991

Delayed-type hypersensitivity and circulating basophils. A population study.

The factors related to delayed-type hypersensitivity (DTH) have been investigated in two samples of elderly non-hospitalized (n = 375) and hospitalized subjects (n = 409). Percent basophils was found to be consistently related to the number of positive responses to seven common antigens in the different samples or subsamples considered. The mean number of responses, after adjustment for age, sex and sample was 1.55 below 0.5% basophils, 1.87 between 0.5 and 1.5% and 1.96 over 1.5% (P less than 0.01). No relation was observed between percent basophils and the mean diameter of the positive responses, suggesting that basophils might be related to the early phase of DTH reactions. As previously reported, the number of positive responses was found to be lower in women than in men and to be inversely related to age.

Age Factors↗
PubMed1991

Biological variability of superoxide dismutase, glutathione peroxidase, and catalase in blood.

We studied the biological variability of blood superoxide dismutase (SOD; EC 1.15.1.1), glutathione peroxidase (GPX; EC 1.11.1.9), and catalase (CAT; EC 1.11.1.6) in a sample of 1836 apparently health subjects, ages 4-97 years. SOD and GPX activities were assayed in plasma (P) and erythrocytes (E) by automated methods, and CAT was measured in erythrocytes by a manual technique. No statistically significant variation of these antioxidant enzyme activities according to gender was demonstrated, except for E-GPX, which was slightly but significantly higher in women than in men (P less than 0.001). Activities appear rather stable in adults less than 65 years old, but decrease for most enzymes in the elderly. There is no evidence that weight, blood pressure, or menopause influences the antioxidant enzymes' activities. In girls ages 10-14 years, E-SOD activity is reduced by 16% (P less than 0.05) after menarche. Variations related to smoking and alcohol consumption are slight and concern only P-SOD and P-GPX, respectively. Conversely, intake of some drugs (e.g., anti-inflammatory agents, antidepressants, and thyroid hormones) modifies activity of some of the three enzymes. E-SOD positively correlates with P-SOD (r = 0.216, P less than 0.001) and E-CAT (r = 0.123, P less than 0.001), and E-GPX with P-GPX (r = 0.218, P less than 0.001). Finally, we propose reference intervals for activities of the three antioxidant enzymes in blood in individuals less than 65 years old.

Adolescent↗
PubMed1990

Familial resemblance of plasma apolipoprotein B: the Nancy study.

The familial resemblance of plasma apolipoprotein B (apo B) was investigated in a sample of 102 families including 419 members who volunteered for a free health checkup in the Preventive Center of Vandoeuvre-lès-Nancy, France. The mean levels (+/- SD) of apo B were 141.0 (+/- 32.6), 121.8 (+/- 27.7), and 98.6 (+/- 22.6) mg/dl in fathers, mothers, and offspring, respectively. The familial correlations were 0.04, 0.13, 0.21 (P less than .01), and 0.47 (P less than .001) between spouses, father-offspring, mother-offspring, and siblings, respectively, after adjustment on age, body mass index, and sex. A genetic analysis was performed using the approach proposed by Bonney, which indicated that a recessive and a dominant major-locus model appeared nearly equally supported by the data. Under the recessive model, the frequency q of the most common allele was estimated as 0.825, with a mean difference of 60.4 mg/dl between high and low homozygotes. Under the dominant model, q was estimated as 0.875, with a mean increase of 34.2 mg/dl in heterozygotes and high homozygotes. However, the hypothesis of Mendelian transmission and the environmental hypothesis could not be formally tested because of great numeric difficulties encountered in the estimation of the three transmission probabilities. Given these analytical restrictions, we cannot conclude in favor of a major locus influencing apo B level in our population, even though the evidence is suggestive. The genetic heterogeneity underlying the familial aggregation of apo B level, suggested by several recent publications, might explain the difficulty in discerning a single major locus in a population sample of small nuclear families, not ascertained through patients enriching the sample in high values of apo B. These findings call into question the relevance of the approach through "healthy" populations in the search for major loci influencing biological traits.

Adult↗
PubMed1989

Vitamin status, immunity and infections in an elderly population.

The relations between vitamin status and immunological parameters or number of infections have been investigated in self-sufficient healthy individuals aged 60 and over. A total of 411 subjects agreed to participate, but 202 were discarded from the main statistical analysis since they could have had their immune or nutritional status modified by a recent infection, vaccination or drug consumption. Plasma concentrations of retinol, alpha-tocopherol, ascorbic acid and vitamin B6 were determined. Three indices of cellular immunity were measured: percentages of T-cell subsets, lymphoproliferative response to phytohaemaglutinin and delayed-type hypersensitivity to 7 ubiquitous antigens. A questionnaire about past infections was presented. Two results, supported by previous experimental observations, should be underlined. Vitamin B6 status was positively related to percentages of T-cell subsets: the lowest percentages of CD5 and CD4 cells were observed in the low B6 status group (50.6 and 32.6 per cent) and the highest percentages in the high B6 status group (62.0 and 41.0 per cent), with intermediate values in the medium group (57.6 and 39.5 per cent). Vitamin E status was negatively related to the number of past infections: subjects with a high alpha-tocopherol plasma concentration had fewer infections during the last 3 years (1.0) than those with a medium (2.2) or a low (2.3) concentration. In spite of these two observations, cellular immunity did not seem to be strongly related to vitamin status in the supposedly healthy population studied.

Aged↗
PubMed1989

Dietary intake and other determinants of blood vitamins in an elderly population.

The relationships of diet, plasma lipids, age, gender, ponderal index, cigarette and alcohol consumption, drug use and infections to blood concentrations of retinol, beta-carotene, alpha-tocopherol, ascorbic acid and vitamins B1, B2, B6 status were studied among 291 men and women aged 60-82 years. Statistically significant correlations between dietary intake and blood indicator levels were found respectively for beta-carotene, alpha-tocopherol, ascorbic acid, vitamins B2 and B6, but not for retinol and thiamin, when the effects of other parameters were controlled. The main other determinants were cigarette consumption which had a negative effect on status for retinol, beta-carotene, alpha-tocopherol, ascorbic acid and vitamin B2; alcohol consumption for retinol, vitamin B6 (positive effect on status) and beta-carotene (decrease of plasma level); plasma lipids and use of hypolipaemic drugs for fat-soluble vitamins; ponderal index for beta-carotene and vitamin B6; gender and use of antibiotics for ascorbic acid. The apparent relation between gender and level of retinol, beta-carotene, alpha-tocopherol and vitamin B6 status was not any more significant after adjustment for alcohol or cigarette consumption. Tobacco and alcohol appear to be associated factors which should be controlled for in studies investigating relations between these vitamins and diseases influenced by smoking and drinking habits.

Age Factors↗
PubMed1988

[Plasma retinol, carotenoids and tocopherols: biological variations between 18 and 45 years of age].

Variation factors of plasma retinol, carotenoids and vitamin E, and particularly sex and alcohol consumption, were studied on a sample of 271 males and females aged between 18 and 45 years. For analysis needs two subsamples were constituted: I (males and females with alcohol consumption less than or equal to 43 g/day) and II (males only). Sex and level of alcohol intake were two independent variation factors of plasma retinol and carotenoids. Associated with triglyceride and cholesterol for I and with triglyceride and ponderal index for II, they explained 40% of the total variance of plasma retinol. For carotenoids, the other associated independent variables were cholesterol, vitamin A and energy intake (r2 = 23% of explained variance). And for plasma vitamin E, neither sex nor alcohol consumption was a significant predictor of the model, the only variation factors being plasma lipids and age for I (r2 = 37%) and the same parameters associated with ponderal index for II (r2 = 55%).

Adult↗
PubMed1988

Seasonal patterns of circulating basophils.

The seasonal patterns of circulating basophils were investigated in a sample of 33,000 French subjects, aged 20-60 years. Circannual variations (minimum in October, maximum in July) which might be related to pollens were observed. Periods with cold weather (temperature below 0 degrees C) correlated to a temporary rise in basophils.

Adult↗