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Three groups of weanling female mice were fed one of two iron-deficient diets (5 and 12 mg Fe/kg diet) or a normal diet (30 mg Fe/kg diet) for 6 wk. A control pair-fed group was included. Seven mice received the 5 mg Fe/kg diet for 6 wk, then were rehabilitated using the 30 mg Fe/kg diet for 10 d. Mice fed the 5 mg Fe/kg diet were moderately iron-deficient, as shown by indices of iron status. No significant differences were observed in thymus weight or in the proportion and number of thymocyte subsets in thymuses of anemic, moderately iron-deficient and control mice. Thymus weight was decreased in pair-fed mice. No significant difference was found in lymph node subsets. In the spleen of anemic mice, the proportions and total number of Thy-1+ splenocytes, CD4-8+ and CD4+8- cells were very low compared with control (P less than 0.01) and iron-deficient (P less than 0.02) mice. The decrease was not only observed for the percentage of subsets but also for the absolute number of cell subtypes per spleen. Thy-1+ splenocyte subpopulations were normalized after rehabilitation. These quantitative modifications could explain alterations in the blastogenic response of splenic lymphocytes described by other authors.  相似文献   
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The 677cytosine mutation identified in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been frequently associated with an elevated plasma homocysteine concentration. The aim of the present study was to determine the impact of this MTHFR common mutation on plasma and erythrocyte folate (RCF) and plasma total homocysteine (tHcy) concentrations in healthy French adults. A cohort of 291 subjects living in the Paris area and participating in the Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) study were analysed to assess the impact of MTHFR polymorphism 677C-->T on folate status and plasma tHcy concentration. The frequency of the mutant homozygote for 677C-->T polymorphism (677TT genotype) in the present cohort was 16.8%. There were significant differences in plasma tHcy between 677CC, 677CT and 677TT genotype groups. The RCF concentrations were significantly different between each genotype, the lowest levels being associated with the 677TT genotype. When segregated by gender, no differences in tHcy between homozygous 677TT, heterozygous 677CT and wild-type 677CC genotype groups in women were observed. The fasting tHcy in women was unrelated to the 677C-->T mutation. However, tHcy was significantly increased in men with the homozygous 677TT genotype. We also analysed the possible implication of a second new MTHFR polymorphism (1298A-->C) in subjects with mild hyperhomocysteinaemia (4th quartile of homocysteinaemia; tHcy >11.1 micromol/l). The polymorphism 1298A-->C did not have a notable effect on tHcy or on the RCF levels. Our observations confirm a relatively high frequency of the 677TT genotype in the French population. Women with this genotype did not show the same increase in tHcy observed in men. In the present study dietary folate intake was not measured. Thus, the interaction of dietary folate with the MTHFR genotype in the French population needs further study.  相似文献   
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Postdiagnosis diet and alcohol consumption may be associated with cancer prognosis, recurrence and mortality. Our aim was to investigate food, nutrient and alcohol intake variations between before and after cancer diagnosis and their determinants in a prospective cohort. Subjects (n = 696) were incident cancer cases diagnosed in the NutriNet‐Santé cohort between 2009 and 2016. Food, nutrient and alcohol intakes were prospectively collected using repeated nonconsecutive 24‐hr dietary records since subjects' inclusion (i.e. an average of 2 y before diagnosis). Mean number of dietary records per subject was 5.9 before and 8.1 after diagnosis. All dietary data before and after diagnosis were compared by mixed models. Factors associated with the main dietary changes observed were also investigated using multivariable logistic regressions. We observed a decrease in intakes of vegetables (mean decrease in intake in patients who decreased their intake=‐102.4 ± 79.8 g/d), dairy products (–93.9 ± 82.8 g/d), meat/offal (–35.5 ± 27.8/d), soy products (–85.8 ± 104.1 g/d), sweetened soft drinks (–77.9 ± 95.4 g/d), and alcoholic drinks (–92.9 ± 119.9 g/d), and an increase in broths (42.1 ± 34.9 g/d) and fats/sauces (18.0 ± 13.4 g/d). We observed a decrease in energy intake (–377.2 ± 243.5 kcal/d) and in intakes of alcohol (–7.6 ± 9.4 g/d) proteins (–17.4 ± 12.5 g/d), and several vitamins (p < 0.05) and micronutrients (p < 0.05). Conversely, lipid (19.4 ± 14.6 g/d), SFA (9.3 ± 7.0 g/d), MUFA (8.3 ± 6.3 g/d) and vitamin E (3.9 ± 3.3 mg/d) intakes increased after diagnosis. This large prospective study suggests that cancer diagnosis is a key period for nutritional changes. It highlights some healthy behaviors such as a decrease in alcohol and sweetened drink consumption, but also less favorable trends, such as a decrease in vegetable consumption and in many vitamin and mineral intakes. These results provide insights to identify and target recommendations to put forward for better nutritional care of cancer survivors.  相似文献   
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In May 2020, the European Commission announced a proposal for a mandatory front-of-pack label (FoPL) for all European Union (EU) countries. Indeed, FoPLs have been recognized by several public institutions as a cost-effective measure to guide consumers toward nutritionally favorable food products. The aim of this study was to compare the performance and consumer preference of two FoPLs currently proposed or implemented in EU countries, the interpretive format Nutri-Score and the non-interpretive format NutrInform Battery, among Italian consumers. The experimental study was conducted in 2021 on a representative sample of 1064 Italian adults (mean age = 46.5 ± 14.1 years; 48% men). Participants were randomized to either Nutri-Score or NutrInform and had to fill out an online questionnaire testing their objective understanding of the FoPL on three food categories (breakfast products, breakfast cereals and added fats) as well as purchase intention, subjective understanding and perception. Multivariable logistic regressions and t-tests were used to analyze the answers. In terms of the capacity of participants to identify the most nutritionally favorable products, Nutri-Score outperformed NutrInform in all food categories, with the highest odds ratio being observed for added fats (OR = 21.7 [15.3–31.1], p < 0.0001). Overall, with Nutri-Score, Italian participants were more likely to intend to purchase nutritionally favorable products than with NutrInform (OR = 5.29 [4.02–6.97], p < 0.0001). Focusing on olive oil, participants of the Nutri-Score group had higher purchase intention of olive oil compared to those in the NutrInform group (OR = 1.92 [1.42–2.60], p < 0.0001) after manipulating the label. The interpretive format Nutri-Score appears to be a more efficient tool than NutrInform for orienting Italian consumers towards more nutritionally favorable food choices.  相似文献   
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