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S Hercberg

Publications and source records attributed to S Hercberg.

At least 127 records · Page 7Linked to original sources

[Dietary intake of a representative sample of the population of Val-de-Marne; III. Mineral and vitamin intake].

Mineral and vitamin intakes were assessed among 1108 subjects, aged 6 months to 97 years in 12 of 47 towns and cities in the district of Val-de-Marne (Paris area), using the telephone directory as random sampling base. Micronutrients intake was evaluated by individual interviews at home by specialized dietitians (dietary history method). Mineral and vitamin intake was found to vary widely with age. In absolute value, overall mineral and vitamin dietary intakes was higher in men than in women (except for vitamin C). Conversely, the dietary density for mineral and vitamins was higher in females. For a large part of the studied population, it would appear difficult to satisfy recommended dietary allowances for many micronutrients (iron, zinc, vit. B1, B6, C, A et E). These results bring to light possible difficulties in covering certain mineral and vitamin requirements in the French population.

Adolescent↗

Is basic red cell ferritin a more specific indicator than serum ferritin in the assessment of iron stores in the elderly?

Iron status was evaluated in 103 elderly institutionalized individuals using haemoglobin concentration, red cell indices, serum iron, serum transferrin, serum ferritin and basic red cell ferritin. Inflammatory processes were identified by measuring concentrations of orosomucoid and C-reactive protein in serum and leukocyte counts. Anaemia was present in 16.5% of the individuals. No serum ferritin values were in the range of depleted iron stores; however 6% of the elderly individuals presented basic red cell ferritin less than 3 attog/cell (3 x 10(-18) g/cell). Serum ferritin was positively correlated with markers of inflammation. Basic red cell ferritin measurement was not influenced by inflammation and may provide a reliable indicator of iron status in the elderly.

Aged↗

Relationship between selenium, immunity and resistance against infection.

1. Food selenium content, selenium supply and selenium needs are presented, along with methods of evaluation of selenium status. Glutathione peroxidase, a selenium-containing enzyme, is ubiquitous in the organism. 2. Some experimental studies on animal models reported a positive relationship between selenium status and resistance against infections. 3. Only one study in humans concerned the mechanisms of immune functions in selenium deficiency. Several experimental works suggest that severe selenium deficiency compromises T-cell dependent immune functions such as the blastogenic response to mitogens, but selenium deficiency was concomitant with vitamin E deficiency in most of them. Delayed hypersensitivity response is controversial in selenium-supplemented rats and guinea-pigs. 4. Selenium deficiency in animals decreases the antibody response, especially if associated with vitamin E deficiency. Low dietary selenium supplementation of healthy animals has a positive effect upon humoral responses. 5. Despite some controversies, most experimental studies on selenium-deficient animals report normal phagocytosis and an altered bactericidal capacity of neutrophils. The decrease in glutathione peroxidase activity of polymorphonuclear cells following selenium deficiency could explain some of these alterations. 6. Splenic Natural Killer cells activity is enhanced in selenium-supplemented, healthy animals.

Animals↗

Effects of iron deficiency upon the antibody response to influenza virus in rats.

The effects of severe and moderate iron deficiency upon the antibody response to influenza virus were investigated in rats. Three groups of weanling male Wistar rats were fed one of two iron-deficient diets (5 mg and 15 mg iron/kg diet) or a normal iron-containing diet (35 mg iron/kg diet). A group of individually pair-fed rats was introduced with the low iron-consuming rats. The effects of the diets upon various iron status parameters were followed during the 4th, 5th, 6th, and 7th week of diet. After 4 weeks of feeding different diets, an intraperitoneal injection of inactivated influenza virus A/New Jersey/76 was performed and a recall injection was done at 5 weeks. Primary and secondary antibody responses were assayed. Rats were sacrificed at 7 weeks of diet. After 4 weeks of feeding different diets, the rats fed the 5 mg iron/kg diet were severely anemic and rats fed 15 mg iron/kg diet were moderately iron-deficient, as shown by their iron status parameters. Growth was delayed in anemic and matched pair-fed rats. A primary antibody response was almost nonexistent in all groups. Secondary antibody titers were significantly weaker in anemic rats than in ad libitum controls, but were not different from those of pair-fed rats. This response was similar in moderately iron-deficient, ad libitum, and pair-fed rats. These results show that antibody synthesis in response to the influenza virus vaccine is preserved in moderate iron deficiency but is reduced in severe anemia. The reduction in energy consumption associated with severe iron deficiency in the rat could play a part in the altered humoral response.

Journal Article↗

Iron absorption from typical West African meals containing contaminating Fe.

Iron absorption from three typical West African meals was measured in fourteen subjects using the extrinsic-tag technique with 59Fe and 55Fe. All meals consisted of maize as the staple food. Meals were prepared in Benin under realistic conditions from locally grown foods. Of the non-haem-Fe in the meals 39-73% did not exchange with the added inorganic radio-Fe tracer, depending on the degree of Fe contamination of meals. Non-haem-Fe absorption was low in each maize meal, but was even lower for those eaten with a vegetable sauce than for those eaten with a fish sauce. When haem-Fe absorption was included, 70.0-160 micrograms Fe was absorbed. Expressed on an energy basis, the bioavailable nutrient density was 3.2-7.0 micrograms/100 kJ (13.4-29.5 micrograms/100 kcal). These findings suggest that total Fe available in the typical diets of West African countries does not meet the physiological requirements of large proportions of the population.

Adult↗

Effect of decreased food consumption during iron deficiency upon growth rate and iron status indicators in the rat.

Weanling Wistar rats were given a low-iron diet (4-5 mg Fe/kg), a medium-iron diet (20 mg Fe/kg) or a control diet (40 mg Fe/kg) for 7 weeks. Pair-fed rats received the control diet in amounts equivalent to that consumed by animals on a low-Fe diet. Blood samples from the tail vein were taken after 4 weeks of diet and weekly during the following 3 weeks for determination of iron status parameters. Animals were weighed weekly. After 4 weeks of diet, the rats fed the 5 mg iron/kg diet were severely anemic and rats fed 20 mg iron/kg diet were moderately iron-deficient. Ad libitum and pair-fed controls had normal iron status. Total liver iron stores were lowest in anemic rats (p less than 0.001) and were also low in moderately iron-deficient animals (p less than 0.05). Growth rates decreased early in anemic and pair-fed rats. Both groups were smaller than controls and moderately iron-deficient rats after 2 weeks (p less than 0.05) and this continued until the end of the experiment (p less than 0.001). Body weights of pair-fed rats were lower than those of anemic rats from the 1st to the 3rd week of diet; thereafter, differences between the two groups were no longer significant.

Anemia, Hypochromic↗

Bioavailable iron density in French and Spanish meals.

Iron absorption from two typical French meals and three typical Spanish meals was measured, using the extrinsic tag technique (with 55Fe and 59Fe) on French and Spanish volunteers. The total iron absorption coefficient varied up to three-fold (between 3.4 and 11.4 per cent) according to the contents of haem and non-haem iron and the presence of non-haem iron absorption enhancers and inhibitors. Expressed for iron absorption of 40 per cent of the reference dose (corresponding to subjects with theoretical depleted iron stores), those coefficients varied up to four-fold (between 4.9 and 18.9 per cent). The bioavailable nutrient density ranged from 0.30 to 0.77 mg/1000 kcal in subjects with good iron stores and from 0.50 to 1.12 mg/1000 kcal for subjects with theoretical depleted iron stores. This low bioavailable iron density enabled understanding of why iron balance is especially critical in women of childbearing age in industrialized countries, where iron enrichment of food is not practised.

Adult↗

[Iron deficiency in pregnancy].

From the evaluation of losses and savings, the authors specify, according to the reserves before pregnancy and the true diet intake, the indications for therapeutic supplement during pregnancy.

Anemia, Hypochromic↗

Iron status, immune capacity and resistance to infections.

1. The importance of iron on immune functions is reviewed. 2. The consequences of iron deficiency upon resistance to infection in men (adults and children) and animals are controversial. 3. Cellular immunity is often altered in iron-deficient humans and in murine species. 4. Humoral immune responses seem far less affected in iron-deficient humans than is cellular immunity, but is impaired in iron-deficient animals. Results on complement are scarce and controversial. 5. There is almost no perturbation of phagocytosis but bactericidal activity is decreased in most studies on iron-deficient subjects. 6. Natural Killer activity is decreased in iron-deficient mice. Iron deficiency also affects lymphokine production in mice and rats.

Animals↗

Effects of different degrees of iron deficiency on cytochrome P450 complex and pentose phosphate pathway dehydrogenases in the rat.

Four groups of weanling male rats were fed one of three iron-deficient diets (6, 18 and 23 mg iron/kg diet) or a normal iron-containing diet (41 mg iron/kg diet) for 30 d. The effects of the diets on various iron status parameters were determined and four enzymes were assayed: cytochrome P450 (P450) and NADPH cytochrome P450 reductase (P450-RED) in liver and intestine microsomes, and glucose-6-phosphate dehydrogenase (G6P-DH) and 6-phosphogluconate dehydrogenase (6PG-DH) in liver, intestine and erythrocyte cytosol. Rats fed 6 mg iron/kg diet were severely anemic, whereas rats fed 18 or 23 mg iron/kg diet were moderately or mildly iron-deficient, as shown by their hemoglobin levels, hematocrit, red blood cell parameters, erythrocyte protoporphyrin and liver iron stores. P450 concentration and P450-RED activity in liver were unaffected by iron deficiency, but P450 concentration was markedly lower in the intestine of the three iron-deficient groups than in the controls. Activities of G6P-DH and 6PG-DH were not impaired in liver or intestine, except that liver 6PG-DH activity of severely anemic rats was less than that of control rats. However, severe and moderate iron deprivation resulted in a stimulation of G6P-DH and 6PG-DH activities per million erythrocytes. These results demonstrate that even moderate iron deficiency may alter fundamental enzymatic systems intervening in drug metabolism and in the pentose phosphate pathway.

Anemia, Hypochromic↗

Biochemical effects of iron deprivation.

The consequences of iron deprivation on iron-containing enzymes of different tissues in rat and/or human is reviewed. Iron participates in a wide variety of biochemical processes, including mitochondrial electron transport, catecholamine metabolism and DNA synthesis. Recently, a broad spectrum of biochemical abnormalities resulting from iron deficiency have been described. Effects on skeletal muscle, cardiac muscle, brain tissue, liver tissue gastrointestinal tractus, body temperature regulation, DNA synthesis are successively discussed. The key liabilities of tissue iron deficiency, even at a mild degree relate to decrease in intellectual performance, and in physical capacity during exercise, alteration of temperature regulation, immune function.

Animals↗

[Comparison of 2 methods for evaluating the prevalence of anemia in young children].

Prevalence of anemia was estimated by two methods in 1235 healthy children 10 months old undergoing a free-of-charge medical checkup in a Parisian Child Health Examination Center. According to the classical method, the frequency of anemia, defined as the percentage of children with hemoglobin concentration below the WHO cut-off point (11 g/dl), amounts to 16.8% of 797 French children, 24.0% of 289 North African children and 43.6% of 149 sub-saharan children. The second method defines the frequency of anemia as the percentage of children whose hemoglobin values are shifted downwards relative to a gaussian hemoglobin distribution in non-anemic children. According to this method, anemia was present in 0.8%, 5.4% and 12.6% of children, respectively. The conventional cut-off point probably tends to overestimate the true frequency of anemia in this age group.

Africa, Northern↗

[Prevention of iron-deficiency anemia in pregnancy using early iron supplementation: a controlled trial].

An iron supplementation trial versus placebo was performed in double blind on 191 attending at 3 month the antenatal clinic of Poissy maternity. Iron status of mothers and newborns was assessed at 3, 5, 7 month, during the delivery and 2 months after the delivery, using biochemical indicators (hemoglobin level, serum ferritin). The compliance was good in 165 pregnant women (86% of the initial sample): 81 in the iron group, 84 in the placebo group. Among the placebo group, anemia (Hb less than 11 g/dl) was observed at the end of the pregnancy in 30% of women. Depletion of iron stores started at 5 month. In the iron group, hemoglobin level increased significantly during the pregnancy and anemia was observed only in 3% of women at the delivery. Iron status of newborns and two months after delivery was related to mothers iron status at delivery and particularly at the 7th month of pregnancy.

Adult↗

Relationship between serum ferritin, erythrocyte protoporphyrin and transferrin saturation in Mauritanian free living children.

Serum ferritin, serum iron, total iron-binding capacity (TIBC) and erythrocyte protoporphyrin were measured in a group of 69 children (6.4 +/- 3.6 years) living in a rural area of Mauritania. The predictive value of low serum ferritin was calculated for each iron parameter. A serum ferritin value above 12 micrograms/l was present in 50.2% of children with abnormal serum iron, in 59.0% of those with abnormal TIBC, in 60.3% of those with abnormal transferrin saturation and in 60.0% of those with abnormal erythrocyte protoporphyrin. The percentages varied from 88.0 to 94.8% for a predictive value of serum ferritin of less than 50 micrograms/l. Nearly 35% of children had biochemical evidence of iron deficiency, i.e. 2 abnormal independent iron parameters or more, including serum ferritin of less than 12 micrograms/l. Nearly 32% had probable iron deficiency, i.e. 2 abnormal independent iron parameters, with a serum ferritin value between 13 and 50 micrograms/l.

Anemia, Hypochromic↗