[Effects of the combination of a pesticide, lindane, and a sulfur depleted diet on pregnancy in the rat]. / Effects de l'association d'un pesticide, le lindane, à un régime pauvre en soufre sur le déroulement de la gestation chez la ratte.

Effects of assocation of lindane ingestion and sulfur depletion on pregnancy in the rat. Sulfoconjugation stands as one of the main processes of foreign compound detoxication in mammals. When feeding conditions are adequate, sulfate ions necessary to form sulfoconjugates are provided by the sulfur aminoacids of the diet. The feeding to pregnant rats of a diet containing lindane, when sulfur aminoacids are limiting factors, should lead to competition between their utilisation for anabolic or detoxifying processes. The balance between stimulation of glucuroconjugation and sulfoconjugation seems to depend on which of the 2 compounds necessary for detoxification is the most limiting factor. Glucuroconjugation spares sulfur aminoacids for foetal growth; sulfoconjugation spares glucose for foetal utilisation. The foetal needs appear to modulate the orientation of the maternal detoxication processes; foetal anabolism is predominent over detoxication.

Blood levels of water-soluble vitamins in pediatric patients on total parenteral nutrition using a multiple vitamin preparation.

Although guidelines for the parenteral use of vitamin preparations in pediatric patients have been published, there are very limited data on the efficiency of these preparations and on the exact needs of infants and children on total parenteral nutrition (TPN). We report here an open, prospective, study of the blood levels of water-soluble vitamins in infants and children on TPN before and during supplementation with a new water-soluble multivitamin formula containing per vial unit: B1, 3 mg; B2, 3.6 mg; B6, 4 mg; niacin, 40 mg; pantothenate, 15 mg; ascorbate, 100 mg; biotin, 60 micrograms; folic acid, 400 micrograms; B12, 5 micrograms. Thirteen children, 9 months to 15 yr old, on home TPN for 1.5 months to 7 yr, and 17 hospitalized infants and children, 1 week to 15 yr old, receiving TPN were studied for 2 weeks to 4 months. Daily doses were given according to age: 1/2 vial if less than 18 months; 1 vial if greater than 18 months and less than 10 years; 1.5 vials if greater than 10 years. Assays for B1, B2, biotin, niacin, plasma and red blood cell (RBC) folates were performed by microbiologic methods, B12 was measured by radioimmunoassay. During the study, B1 levels were consistently above the upper limit of the normal range, B2 and B12 remained in the normal range although there was a slight decrease in B12 values. Almost half of the patients had initially low levels of biotin, niacin, and folates. Biotin, after a significant sharp rise during the first month of supplementation returned to normal range. Niacin levels were initially low in infants and rose toward normal values during treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between maternal folate status and foetal hypotrophy in a population with a good socio-economical level.

A longitudinal study was conducted on 2 groups of pregnant women according to the presence (n = 8) or absence (n = 13) of IUGR through echography at the 3rd trimester of pregnancy. Mothers answered a general questionnaire, including some alimentary data. Anthropometric measures from the newborns were recorded. Haematological parameters and folate status of the women at 32 weeks of pregnancy and of the mother and child at delivery were assessed. Although a significant cross correlation (p < 0.02) between the newborns' folate status and the mother's one, including folate intake, was obtained, no relationship was found between birthweight and folate status at delivery. In contrast, the study evidences significant correlations between birthweight and both folate status of the mother at the third trimester of pregnancy (p < 0.02) and the decrease of her erythrocyte folate level before delivery (p < 0.01). In our sample, folate status of the pregnant woman at the third trimester offers a predictive value of the newborn weight, but this result remains to be confirmed in a larger study.

A polymorphism (80G->A) in the reduced folate carrier gene and its associations with folate status and homocysteinemia.

5-methyltetrahydrofolate is the predominant form of folate in plasma. It may be the preferred substrate for transport via the reduced-folate carrier (RFC). We isolated a cDNA for the reduced folate carrier (RFC-1) from human skin fibroblasts. A common polymorphism at position 80 in exon 2 of RFC-1 was identified. This polymorphism changes a guanine (G) to an adenine (A), abolishing a CfoI restriction site. Using genomic DNA samples from 169 healthy subjects, we identified 27.1% GG homozygotes, 21.9% AA homozygotes, and 50.9% GA heterozygotes. We explored the impact of this polymorphism, separately and in combination with the 677C->T polymorphism in the methylenetetrahydrofolate reductase gene, on folate status and total homocysteine levels. We found a moderate, but significant, increase in total homocysteine levels in doubly homozygous 80GG/677TT subjects as compared to 80GG/677CC (P = 0.01) or 80GG/677CT (P = 0.04) subjects. In addition, individuals who were 80AA/677CT had higher plasma folate levels than those who were 80GG/677CT (P = 0.02).