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OBJECTIVES: To test the hypothesis that maternal plasma alpha-tocopherol levels are associated with protection from childhood wheeze and that this protection is modified by gamma-tocopherol. STUDY DESIGN: We conducted a prospective nested study in the Infant Susceptibility to Pulmonary Infections and Asthma Following Respiratory Syncytial Virus Exposure birth cohort of 652 children with postpartum maternal plasma vitamin E isoforms used as a surrogate for pregnancy concentrations. Our outcomes were wheezing and recurrent wheezing over a 2-year period, ascertained using validated questionnaires. We assessed the association of alpha- and gamma-tocopherol with wheezing outcomes using multivariable adjusted logistic regression, and tested for interaction between the isoforms with respect to the risk for wheezing outcomes. RESULTS: Children with wheezing (n = 547, n = 167; 31%) and recurrent wheezing (n = 545, n = 55; 10.1%) over a 2-year period were born to mothers with significantly lower postpartum maternal plasma concentrations of alpha-tocopherol, P = .016 and P = .007, respectively. In analyses of IQR increases, alpha-tocopherol was associated with decreased risk of wheezing (aOR 0.70 [95% CI 0.53,0.92]) and recurrent wheezing (aOR 0.63 [95% CI 0.42,0.95]). For gamma-tocopherol, the aOR for wheezing was 0.79 (95% CI 0.56-1.10) and the aOR for recurrent wheezing was 0.56 (95% CI 0.33-0.94, with nonmonotonic association). The association of alpha-tocopherol with wheezing was modified by gamma-tocopherol (P interaction = .05). CONCLUSIONS: Increases in postpartum maternal plasma alpha-tocopherol isoform concentrations were associated with decreased likelihood of wheezing over a 2-year period. Gamma-tocopherol modified this association.

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Fiber microparticles (MPCs) separately obtained from peel and pulp of Japanese plum residues contained co-extracted ß-carotene, lutein, and α- and γ-tocopherols, as well as polyphenols (cyanidins, quercetin derivatives, pentameric proanthocyanidins). Peel and pulp MPCs were then separately evaluated as natural antioxidant additives (2.0% w/w level) in raw breast chicken patty, susceptible to oxidation. Their effect on technological properties was also analyzed. MPCs reduced in 50% the formation of thiobarbituric acid reactive substances (TBARS) in raw patties during 10-days storage at 4.0°C. Ferric reducing power (FRAP) was 77-157% higher in MPCs-added patties, especially with peel MPCs, being then attributed to the antioxidants supplied by these MPCs. It can be also associated to the highest α- and γ-tocopherol levels found in the peel MPCs-added patties, which remained high after cooking as well. Also, higher pectin and low lignin contents of pulp MPCs determined greater hydration, stabilized the cyanidins and, hence, the red color transferred to raw patties, and increased springiness of cooked patties. Plum peel and pulp MPCs are efficient additives for chicken meat products.

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We examined the effect of maternal smoking on plasma and urinary levels of vitamin E isoforms in preterm infants. Maternal smoking during pregnancy decreased infant plasma alpha- and gamma-tocopherol concentrations at 1 week and 4 weeks, with 45% of infants of smokers deficient in alpha-tocopherol at 1 month after birth.

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O alfa- e o gama-tocoferol estão entre os homólogos da vitamina E, que possui importante papel como antioxidante. As fontes dietéticas mais ricas em vitamina E são os óleos vegetais. Este trabalho avaliou os níveis de alfa- e gama-tocoferol nos óleos de canola, girassol, milho e soja, e averiguou sua variação com o tempo de armazenamento. Os óleos vegetais foram adquiridos nos supermercados da cidade de Natal/RN, e mantidos sob temperatura ambiente e ao abrigo da luz. As análises foram realizadas em diferentes momentos durante o armazenamento (tempo 0 e após 30, 60 e 90 dias). Cromatografia líquida de alta eficiência (CLAE) foi usada para determinar as concentrações dos analitos. A análise estatística foi realizada utilizando-se o teste de variância (ANOVA) e as diferenças foram consideradas estatisticamente significativas quando p < 0,05. Ao final do tempo de armazenamento (90 dias) foi verificada diminuição significativa nos níveis de alfa- e gama-tocoferolde 38,7 % e 36,0 %, no óleo de canola; 42,2 % e 22,2 %, no óleo de soja; 28,3 % e 29,2 %, no óleo de girassol;39,0 % e 17,9 %, no óleo de milho, respectivamente. As concentrações de alfa- e gama-tocoferol nos óleos vegetais reduziram significativamente após armazenamento, sob as condições empregadas no estudo.

The alpha- and gamma-tocopherol are among the homologues of vitamin E which plays a key role as anantioxidant. The richest dietary sources of vitamin E are vegetable oils. This study aimed at evaluating thealpha- and gamma-tocopherol contents in oils from canola, sunflower, corn and soybeans, and to verify their variations after storage time. The vegetable oils were purchased at supermarkets in Natal / RN, and they were keptat room temperature and protected from light. The tests was made at different times during storage (time 0 and after 30, 60 and 90 days). The high performance liquid chromatography (HPLC) was used to determinetheir concentrations. The statistical analysis was performed using analysis of variance (ANOVA) test and thedifferences were considered statistically significant when p < 0.05. By the end of the storage time (90 days), thealpha- and gamma-tocopherol contents showed a significant decrease of 38.7 % and 36.0 % for canola oil; 42.2 %and 22.2 % in soybean oil; 28.3 % and 29.2 % in sunflower oil; 39.0 % and 17.9 % in corn oil, respectively.The concentrations of alpha- and gamma-tocopherol in vegetable oils significantly decreased after the storageperiod under the conditions used in this study.

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The alpha- and gamma-tocopherol are among the homologues of vitamin E which plays a key role as an antioxidant. The richest dietary sources of vitamin E are vegetable oils. This study aimed at evaluating the alpha- and gamma-tocopherol contents in oils from canola, sunflower, corn and soybeans, and to verify their variations after storage time. The vegetable oils were purchased at supermarkets in Natal / RN, and they were kept at room temperature and protected from light. The tests was made at different times during storage (time 0 and after 30, 60 and 90 days). The high performance liquid chromatography (HPLC) was used to determine their concentrations. The statistical analysis was performed using analysis of variance (ANOVA) test; and the differences were considered statistically significant when p 0.05. By the end of the storage time (90 days), the alpha- and gamma-tocopherol contents showed a significant decrease of 38.7 % and 36.0 % for canola oil; 42.2 % and 22.2 % in soybean oil; 28.3 % and 29.2 % in sunflower oil; 39.0 % and 17.9 % in corn oil, respectively. The concentrations of alpha- and gamma-tocopherol in vegetable oils significantly decreased after the storage period under the conditions used in this study.(AU)

O alfa- e o gama-tocoferol estão entre os homólogos da vitamina E, que possui importante papel como antioxidante. As fontes dietéticas mais ricas em vitamina E são os óleos vegetais. Este trabalho avaliou os níveis de alfa- e gama-tocoferol nos óleos de canola, girassol, milho e soja, e averiguou sua variação com o tempo de armazenamento. Os óleos vegetais foram adquiridas nos supermercados da cidade de Natal/RN, e mantidos sob temperatura ambiente e ao abrigo da luz. As análises foram realizadas em diferentes momentos durante o armazenamento (tempo 0 e após 30, 60 e 90 dias). Cromatografia líquida de alta eficiência (CLAE) foi usada para determinar as concentrações dos analitos. A análise estatística foi realizada utilizando-se o teste de variância (ANOVA); as diferenças foram consideradas estatisticamente significativas quando p 0,05. Ao final do tempo de armazenamento (90 dias) foi verificada diminuição significativa nos níveis de alfa- e gama-tocoferol de 38,7 % e 36,0 %, no óleo de canola; 42,2 % e 22,2 %, no óleo de soja; 28,3 % e 29,2 %, no óleo de girassol; 39,0 % e 17,9 %, no óleo de milho, respectivamente. As concentrações de alfa- e gama-tocoferol nos óleos vegetais reduziram significativamente após armazenamento, sob as condições empregadas no estudo.(AU)

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Estudios epidemiologicos han demostrado el efecto del estado nutricional de los tocoferoles y el desarrollo de enfermedades cardiovasculares, las cuales son cada vez mas frecuentes en edades tempranas de la vida. Este trabajo relaciona el colesterol total con las concentraciones sericas de tocoferoles en una poblacion de ninos mexicanos, evaluando ademas su estado antioxidante y oxidante. De octubre a diciembre de 2003, se cuantifico en suero a-tocoferol, γ-tocoferol y colesterol total en 1155 niños (12-59 meses) residentes de localidades urbanas y rurales; se evaluo la capacidad antioxidante y el estado oxidante con la produccion de TBARS. Los ninos con cifras de colesterol > 240 mg/dL fue de 577.3 ± 200.8 μg/dL. Sin embargo, cuando se expresaron los tocoferoles en relacion con el colesterol total (μmol/mmol), se observo que los niños con + 1.19), lo que los ubicaba en un adecuado estado nutricional de a-tocoferol, a diferencia del grupo con > 240 mg/dL de colesterol en quienes la relacion fue baja (1.93 ± 0.69). No se observaron diferencias en la capacidad antioxidante del suero, pero si en la produccion de TBARS para los niños con > 200 mg/dL de colesterol. En preescolares los incrementos en el colesterol total limitan la disponibilidad de tocoferoles sericos para los lipidos circulantes, esta condicion a traves del tiempo puede condicionar el desarrollo prematuro de lesiones vasculares mediadas por estres oxidativo.

Epidemiological studies have shown the effect of nutritional status of tocopherols and development of cardiovascular diseases that now are more frequent during early years of life. In this work we evaluated the association between the total cholesterol and serum levels of tocopherols in a population of Mexican children in whom we measured the oxidant status and antioxidant capacity (December 2003). In 1155 children (12-59 months) residents of urban and rural locations we quantified in serum a-tocopherol, γ-tocopherol and total cholesterol; the antioxidant capacity and oxidative status were evaluated with the production of TBARS. Children with serum cholesterol > 240 mg/dL cholesterol recorded an average of 577.3 ± 200.8 μg/dL. However, when tocopherols were expressed in relation to total cholesterol (μmol/mmol) found that children with > 240 mg/dL of cholesterol in whom the relationship was low (1.93 ± 0.69). There were no differences in serum antioxidant capacity, but if in the production of TBARS for children with > 200 mg/dL cholesterol. In preschools the increases in total cholesterol limits the availability of serum tocopherol for circulating lipids, this condition over time could determine the early development of vascular injury mediated by oxidative stress.

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