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981.

Purpose

Folate, vitamins B12 and B6, riboflavin, and methionine are critical nutrients for the one-carbon metabolism cycle involved in DNA synthesis and epigenetic processes. We examined the association between maternal intake of these nutrients before pregnancy and risk of childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) in a matched case–control study.

Methods

Maternal dietary intake and vitamin supplement use in the year before pregnancy was assessed by food frequency questionnaire for 681 ALL cases, 103 AML cases, and 1076 controls. Principal component analysis was used to construct a variable representing combined nutrient intake, and conditional logistic regression estimated the odds ratio (OR) and 95% confidence interval (CI) for the association of ALL and AML with the principal component and each nutrient.

Results

Higher maternal intake of one-carbon metabolism nutrients from food and supplements combined was associated with reduced risk of ALL (OR for one-unit change in the principal component = 0.91, CI 0.84–0.99) and possibly AML (OR for the principal component = 0.83, CI 0.66–1.04). When analyzed separately, intake of supplements high in these nutrients was associated with a reduced risk of ALL in children of Hispanic women only.

Conclusions

In conclusion, these data suggest that higher maternal intake of one-carbon metabolism nutrients may reduce risk of childhood leukemia.
  相似文献   
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An infection trial and a production trial over 35 days were conducted in parallel to study the influence of feeding crimped kernel maize silage (CKMS) on the intestinal Campylobacter jejuni colonization and broiler performance, respectively. The CKMS was used at dietary inclusion levels of 15% and 30% in maize-based diets. Broilers were orally inoculated with 2?×?105?log?cfu/ml C. jejuni on day 14. Four birds from each pen were randomly selected and killed by cervical dislocation on days 3, 6, 9, 14 and 21 post infection and intestinal contents from ileum, caeca and rectum as well as liver samples were taken. Body weight and feed consumption of broilers were registered on days 13, 22 and 35. On day 35, litter dry matter (DM) was measured and the condition of the foot pads was evaluated. There was no significant effect of CKMS on the colonization of C. jejuni. Body weight of the broilers supplemented with 15% CKMS was comparable with the control maize-based feed, whereas addition of 30% CKMS reduced broiler body weight (P?Campylobacter colonization, but improved the foot pad health of broilers.  相似文献   
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There are no reports about the association of interleukin (IL)-17A and IL-17F gene polymorphism and susceptibility to pediatric systemic lupus erythematosus (pSLE). Objective: To examine the possible role of IL-17A rs2275913, IL-17F rs763780 and rs2397084 polymorphisms as risk factors for pSLE in a cohort of Egyptian children and to investigate their association with the clinico-pathological features including lupus nephritis (LN). Methods: Typing of IL-17A and IL-17F polymorphisms was done using restriction fragment length polymorphism for 115 children with SLE and 259 age- and sex-matched healthy controls. Results: No significant differences were found between pSLE patients and healthy controls for the allele and genotype frequencies of IL-17A rs2275913, IL-17F rs763780 and rs2397084 (p?>?0.05). However, the combined genotype GGAGAA and the haplotype GGA had significant association with pSLE (pc?=?0.042 and <0.001, respectively). The AA genotype of IL-17F rs763780 is more frequent in female patients (p?=?0.002) and the AA genotype of IL-17F rs2397084 is more associated with positivity of ds-DNA (p?=?0.007). No more associations were found for the demographic and clinical data of pSLE patients including risk of LN development, risk of non-remission, overall survival, activity and chronicity indices. Conclusion: The GGAGAA combined genotype and the GGA haplotype of IL-17A rs2275913, IL-17F rs763780 and rs2397084 can be considered risk factors for the development of SLE in Egyptian children. IL-17A rs2275913, IL-17F rs763780 and rs2397084 are not related to the LN development, SLE disease activity or overall survival.  相似文献   
990.
Phytochemical investigation of Ficus pandurata Hance (Moraceae) fruits has led to the isolation of two new triterpenoids, ficupanduratin A [1β-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (11) and ficupanduratin B [21α-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (17), along with 20 known compounds: α-amyrin acetate (1), α-amyrin (2), 3β-acetoxy-20-taraxasten-22-one (3), 3β-acetoxy-11α-methoxy-olean-12-ene (4), 3β-acetoxy-11α-methoxy-12-ursene (5), 11-oxo-α-amyrin acetate (6), 11-oxo-β-amyrin acetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione (9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), β-sitosterol (13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3β,21β-dihydroxy-11α-methoxy-olean-12-ene (16), 3β-hydroxy-11α-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11α,21α-dihydroxy-3β-acetoxy-urs-12-ene (21), and β-sitosterol-3-O-β-d-glucopyranoside (22). Compound 21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on the basis of IR, 1D (1H and 13C), 2D (1H–1H COSY, HSQC, HMBC and NOESY) NMR and MS spectroscopic data, in addition to comparison with literature data. The isolated compounds were evaluated for their anti-microbial, anti-malarial, anti-leishmanial, and cytotoxic activities. In addition, their radioligand displacement affinity on opioid and cannabinoid receptors was assessed. Compounds 4, 11, and 15 exhibited good affinity towards the CB2 receptor, with displacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds in the active site of the CB2 cannabinoid receptors was investigated through molecular modelling.  相似文献   
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