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BACKGROUND Investigations of folate-mediated one-carbon metabolism (FOCM) genes and gene-nutrient interactions with respect to colorectal cancer (CRC) risk are limited to candidate polymorphisms and dietary folate. This study comprehensively investigated associations between genetic variants in FOCM and CRC risk and whether the FOCM nutrient status modified these associations. METHODS Two hundred eighty-eight candidate and tagging single-nucleotide polymorphisms (SNPs) in 30 FOCM genes were genotyped for 821 incident CRC case-control matched pairs in the Women's Health Initiative Observational Study cohort. FOCM biomarkers (red blood cell [RBC] folate, plasma folate, pyridoxal-5′-phosphate [PLP], vitamin B12, and homocysteine) and self-reported alcohol consumption were measured at the baseline. Conditional logistic regression was implemented; effect modification was examined on the basis of known enzyme-nutrient relations. RESULTS Statistically significant associations were observed between CRC risk and functionally defined candidate SNPs of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1; K134R), 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR; P450R), and PR domain containing 2 with ZNF domain (PRDM2; S450N) and a literature candidate SNP of thymidylate synthase (TYMS; g.676789A>T; nominal P

Folate-mediated one-carbon metabolism is essential for DNA synthesis, repair, and methylation. Perturbations in one-carbon metabolism have been implicated in increased risk of some cancers and may also affect inflammatory processes. We investigated these interrelated pathways to understand their relation. The objective was to explore associations between inflammation and biomarkers of nutritional status and one-carbon metabolism. In a cross-sectional study in 1976 women selected from the Women's Health Initiative Observational Study, plasma vitamin B-6 [pyridoxal-5'-phosphate (PLP)], plasma vitamin B-12, plasma folate, and RBC folate were measured as nutritional biomarkers; serum C-reactive protein (CRP) and serum amyloid A (SAA) were measured as biomarkers of inflammation; and homocysteine and cysteine were measured as integrated biomarkers of one-carbon metabolism. Student's t, chi-square, and Spearman rank correlations, along with multiple linear regressions, were used to explore relations between biomarkers; additionally, we tested stratification by folic acid fortification period and multivitamin use. With the use of univariate analysis, plasma PLP was the only nutritional biomarker that was modestly significantly correlated with serum CRP and SAA (ρ = -0.22 and -0.12, respectively; P < 0.0001). Homocysteine (μmol/L) showed significant inverse correlations with all nutritional biomarkers (ranging from ρ = -0.30 to ρ = -0.46; all P < 0.0001). With the use of multiple linear regression, plasma PLP, RBC folate, homocysteine, and cysteine were identified as independent predictors of CRP; and PLP, vitamin B-12, RBC folate, and homocysteine were identified as predictors of SAA. When stratified by folic acid fortification period, nutrition-homocysteine correlations were generally weaker in the postfortification period, whereas associations between plasma PLP and serum CRP increased. Biomarkers of inflammation are associated with PLP, RBC folate, and homocysteine in women. The connection between the pathways needs to be further investigated and causality established. The trial is registered at clinicaltrials.gov as NCT00000611.

DNA methylation is an epigenetic mechanism that regulates gene expression and can be modified by one-carbon nutrients. The objective of this study was to investigate the impact of folic acid (FA) fortification of the US food supply on leukocyte global DNA methylation and the relationship between DNA methylation, red blood cell (RBC) folate, and other one-carbon biomarkers among postmenopausal women enrolled in the Women's Health Initiative Observational Study. We selected 408 women from the highest and lowest tertiles of RBC folate distribution matching on age and timing of the baseline blood draw, which spanned the pre- (1994–1995), peri- (1996–1997), or post-fortification (1998) periods. Global DNA methylation was assessed by liquid chromatography-tandem mass spectrometry and expressed as a percentage of total cytosine. We observed an interaction (P = 0.02) between fortification period and RBC folate in relation to DNA methylation. Women with higher (vs. lower) RBC folate had higher mean DNA methylation (5.12 vs. 4.99%; P = 0.05) in the pre-fortification period, but lower (4.95 vs. 5.16%; P = 0.03) DNA methylation in the post-fortification period. We also observed significant correlations between one-carbon biomarkers and DNA methylation in the pre-fortification period, but not in the peri- or post-fortification period. The correlation between plasma homocysteine and DNA methylation was reversed from an inverse relationship during the pre-fortification period to a positive relationship during the post-fortification period. Our data suggest that (1) during FA fortification, higher RBC folate status is associated with a reduction in leukocyte global DNA methylation among postmenopausal women and; (2) the relationship between one-carbon biomarkers and global DNA methylation is dependent on folate availability.

Background: The role of one-carbon metabolism nutrients in colorectal carcinogenesis is not fully understood. Associations might be modified by mandated folic acid (FA) fortification or alcohol intake. Objective: We investigated associations between intakes of folate, riboflavin, vitamin B-6, and vitamin B-12 and colorectal cancer (CRC) in the Women's Health Initiative Observational Study, stratified by time exposed to FA fortification and alcohol intake. Design: A total of 88,045 postmenopausal women were recruited during 1993–1998; 1003 incident CRC cases were ascertained as of 2009. Quartiles of dietary intakes were compared; HRs and 95% CIs were estimated by Cox proportional hazards models. Results: Dietary and total intakes of vitamin B-6 in quartile 4 compared with quartile 1 (HR: 0.80; 95% CI: 0.66, 0.97 and HR: 0.80; 95% CI: 0.66, 0.99, respectively) and total intakes of riboflavin (HR: 0.81; 95% CI: 0.66, 0.99) were associated with reduced risk of CRC overall and of regionally spread disease. In current drinkers who consumed

Previous research suggests 20% of omnivores and 40% of vegetarians do not consume enough vitamin B12. The contribution of seafood to dietary B12 intake stratified by frequency of seafood consumption and B12 status of young adults was assessed. Seafood was the greatest contributor to B12 intake (31%) among nonvegetarians, and intake comparisons based on frequency of seafood consumption revealed that frequent seafood consumers had higher (p < 0.001) B12 intakes. None of the frequent seafood consumers had suboptimal status, which occurred mainly in subjects consuming seafood < 1 time/month and vegetarians. Our findings suggest that modest seafood intake contributes to maintaining normal B12 status.

Background: It has been hypothesized that the response of holo-transcobalamin (holo-TC) to oral vitamin B -12 may be used to assess absorption. To develop a reliable clinical absorption test that uses holo-TC, it is necessary to determine the optimal timeline for vitamin B-12 administration and postdose assessment. Objective: The objective of this study was to assess the magnitude and patterns of change in the postabsorption response of holo-TC to oral vitamin B-12. Design: Adult (18 -49 y) male and female participants (n = 21) with normal vitamin B-12 status were given three 9-μg doses of vitamin B-12 at 6-h intervals beginning early morning (baseline) on day 1. Blood was drawn at 17 timed intervals over the course of 3 d for the analysis of holo-TC and other indicators of vitamin B-12 status. Results: Mean holo-TC increased significantly (P < 0.001) from baseline at 6 h (11%) and 24 h (50%). TC saturation increased significantly (P < 0.001) from baseline at 12.5 h (33%) and 24 h (50%). The mean cobalamin concentration changed significantly (P

Whether folate status and the methylenetetrahydrofolate reductase (MTHFR) 677C-->T polymorphism interact to affect methionine-cycle metabolite concentrations is uncertain. We evaluated the effects of dietary folate restriction on relations among folate status indices and plasma concentrations of methionine cycle metabolites in women with the MTHFR 677 C/C and T/T genotypes. Healthy, normohomocysteinemic women (n = 18; 20-30 y old) of adequate B vitamin status, and equally divided according to MTHFR 677C-->T genotype (9 C/C and 9 T/T) were recruited. Folate status indices and methionine cycle metabolites were measured in blood samples collected at baseline and after 7 wk of dietary folate restriction (115 microg dietary folate equivalents/d). Significant negative correlations between plasma total homocysteine concentrations and total or 5-methyl folate concentrations (P = 0.041 and 0.023, respectively) in RBCs were found only in T/T subjects. Formylated folates were detected in RBCs of T/T subjects only, and their abundance was predictive of plasma total homocysteine concentration despite no significant alteration by folate restriction. Plasma concentrations of S-adenosylmethionine and S-adenosylhomocysteine were not significantly affected by dietary folate restriction and the MTHFR 677 T/T genotype. In conclusion, plasma total homocysteine concentrations in subjects with the MTHFR 677 T/T genotype were inversely related to 5-methyl folate concentrations and directly related to formylated folate concentrations in RBCs, even though the latter were not significantly affected by moderate folate restriction.

Investigations of folate-mediated one-carbon metabolism (FOCM) genes and gene-nutrient interactions with respect to colorectal cancer (CRC) risk are limited to candidate polymorphisms and dietary folate. This study comprehensively investigated associations between genetic variants in FOCM and CRC risk and whether the FOCM nutrient status modified these associations.Two hundred eighty-eight candidate and tagging single-nucleotide polymorphisms (SNPs) in 30 FOCM genes were genotyped for 821 incident CRC case-control matched pairs in the Women's Health Initiative Observational Study cohort. FOCM biomarkers (red blood cell [RBC] folate, plasma folate, pyridoxal-5'-phosphate [PLP], vitamin B12, and homocysteine) and self-reported alcohol consumption were measured at the baseline. Conditional logistic regression was implemented; effect modification was examined on the basis of known enzyme-nutrient relations.Statistically significant associations were observed between CRC risk and functionally defined candidate SNPs of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1; K134R), 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR; P450R), and PR domain containing 2 with ZNF domain (PRDM2; S450N) and a literature candidate SNP of thymidylate synthase (TYMS; g.676789AT; nominal P .05). In addition, suggestive associations were noted for tagging SNPs in cystathionine-β-synthase (CBS), dihydrofolate reductase (DHFR), DNA (cytosine-5-)-methyltransferase 3β (DNMT3B), methionine adenosyltransferase I α (MAT1A), MTHFD1, and MTRR (nominal P .05; adjusted P, not significant). Significant interactions between nutrient biomarkers and candidate polymorphisms were observed for 1) plasma/RBC folate and folate hydrolase 1 (FOLH1), paraoxonase 1 (PON1), transcobalamin II (TCN2), DNMT1, and DNMT3B; 2) plasma PLP and TYMS TS3; 3) plasma B12 and betaine-homocysteine S-methyltransferase 2 (BHMT2); and 4) homocysteine and methylenetetrahydrofolate reductase (MTHFR) and alanyl-transfer RNA synthetase (AARS).Genetic variants in FOCM genes are associated with CRC risk among postmenopausal women. FOCM nutrients continue to emerge as effect modifiers of genetic influences on CRC risk.

Enterotoxigenic Escherichia coli (ETEC) is the most commonly isolated pathogen responsible for travelers' diarrhea and the cause of up to 650 million cases of pediatric diarrhea per year in the developing world. As a safe alternative to the prophylactic use of antibiotics, a hyperimmune bovine milk antibody product with specific activity against purified colonization factor antigens (CFAs) was developed and evaluated in a human challenge study. Twenty-five healthy adult volunteers were challenged orally with 10(9) cfu of a virulent CFA/I-bearing ETEC. In the randomized double-blind trial, 7 of 10 volunteers receiving a lactose-free placebo developed clinical diarrhea after challenge, compared with only 1 of 15 cases in volunteers receiving active product (Fisher's exact test, P < .0017). It is concluded that antibodies against CFAs alone are sufficient for protection and that prophylaxis with milk-derived immunoglobulin is a feasible alternative to existing drug interventions.

Vitamin B12, a co-factor in methyl-group transfer, is important in maintaining DNA (deoxycytidine) methylation. Using two independent assays we examined the effect of vitamin B12-deficiency (plasma vitamin B12

The incidence of diarrhea due to six categories of diarrheogenic Escherichia coli was determined in two pediatric cohorts in a low socioeconomic level community in Santiago, Chile, with access to chlorinated water. An age cross-sectional cohort of 340 children aged birth to 47 months was assembled. A newborn cohort was assembled by enrolling 10-12 newborns monthly for 12 months. Episodes of diarrhea were detected by twice weekly household visits. E. coli from stool cultures of cases and matched controls were hybridized with DNA probes specific for enterotoxigenic, enteroinvasive, enteropathogenic, enterohemorrhagic, enteroaggregative, and diffuse adherence E. coli. Overall, the incidence of diarrhea was low (2.1 episodes/infant/year). Nevertheless, a putative E. coli enteropathogen was found in a large proportion of diarrheal episodes, particularly during the summer. In both cohorts, enterotoxigenic E. coli were important pathogens. Enteropathogenic E. coli were incriminated during the first year of life in the newborn cohort, where they were found significantly more often in cases (p = 0.021) than in controls; beyond this age, isolation rates were similar. In contrast, the relative risk of isolation of diffuse adherence E. coli increased with age in the age cross-sectional cohort, where, overall, the difference in rate of isolation between cases and controls was significant (p = 0.0024). Enteroinvasive and enterohemorrhagic E. coli were isolated infrequently. Enteroaggregative E. coli were encountered equally in cases and controls. Facile transmission of E. coli enteropathogens is occurring in this community despite the availability of potable water.Researchers conducted an age cross sectional cohort analysis of 340 0-47 month old children and newborn cohort analysis of 144 newborns to determine the diarrheogenic Escherichia coli incidence in Santa Julia, a low socioeconomic community in Santiago, Chile. Children in the age cross sectional cohort had age, sex, and sector matched controls. The newborns had sex matched controls. A public health nurse or nurse auxiliary visited the household of each subject 2 times a week to detect diarrhea episodes. Between December 1986 and February 1990, the age cross sectional cohort had 1178 episodes of diarrhea and the newborn cohort had 674 episodes. The overall diarrhea incidence was only 2.1 episodes/child/year. An E. coli enteropathogen was isolated in many of these episodes, especially during the summer (e.g. enterotoxigenic E. coli [ETEC], 2.2 cases/month in summer vs. 0.4 cases/month in winter; p = .00001). Diffuse adherence E. coli (DAEC) and enteropathogenic E. coli (EPEC) infections also peaked in the summer. ETEC contributed greatly to diarrheal episodes in both cohorts. Among newborns, EPEC was isolated significantly more often in cases than controls during the 1st 12 months of life (6.7% vs. 2.5%; p = .021). After 1 year, however, E. coli isolation rates were essentially the same. On the other hand, in the age cross sectional cohort, the relative risk of isolation of DAEC rose with age (e.g., 1.1 for 0.11 months, 1.4 for 36-47 months, and 2.1 for = or 48 months). In the same cohort, DAEC infections were much more common in cases than controls (16.6% vs. 11.9%; p = .0024). Enteroinvasive and enterohemorrhagic E. coli were the most rarely isolated E. coli types. No difference in the isolation rate of enteroaggregative E. coli existed between cases and controls. Since most households in Santa Julia have access to potable water (68%) and an indoor toilet (64%), food contamination were likely the vehicles of E. coli transmission because more than 50% of households do not have a refrigerator.

Thirty-six consecutive patients with invasive Haemophilus influenzae type b (Hib) infections at Roberto del Rio Children's Hospital, Santiago, Chile, were enrolled in a prospective study. Throat cultures were obtained from household contacts of each index case, adjacent neighbors, and matched community control households. Colonization rates for H. influenzae were comparable among groups; however, among household contacts 18% of colonizing isolates were Hib, compared with 2% and 3% among neighbor and community controls. When selected isolates were evaluated further by outer membrane protein (OMP) profiles and multilocus enzyme electrophoresis, only one of the four Hib isolates from household members matched the corresponding index case isolate. One serologically nontypeable isolate from a household contact had an OMP profile and electrophoretic type identical to that of the corresponding Hib index case isolate; hybridization studies with a 9-kb capsular gene probe showed a profile consistent with a capsule-deficient mutant. Hib strains were isolated more frequently from household contacts than from control persons living in Santiago, but colonizing Hib strains were often unrelated to the index case strain.

Background: A common genetic polymorphism [transcobalamin (TC) 776C→G] may affect the function of transcobalamin, the protein required for vitamin B-12 cellular uptake and metabolism. Remethylation of homocysteine is dependent on the production of 5-methyltetrahydrofolate and adequate vitamin B-12 for the methionine synthase reaction. Objectives: The objectives were to assess the influence of the TC 776C→G polymorphism on concentrations of the transcobalamin-vitamin B-12 complex (holo-TC) and to determine the combined effects of the TC 776C→G and methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphisms and vitamin B-12 status on homocysteine concentrations. Design: Healthy, nonpregnant women (n = 359; aged 20-30 y) were screened to determine plasma vitamin B-12, serum holo-TC, and plasma homocysteine concentrations and TC 776C→G and MTHFR 677C→T genotypes. Results: The serum holo-TC concentration for women with the variant TC 776 GG genotype was significantly different (P = 0.0213) from that for subjects with the CC genotype (74 ± 37 and 87 ± 33 pmol/L, respectively). An inverse relation was observed between plasma homocysteine concentrations and both serum holo-TC (P ≤ 0.0001) and plasma vitamin B-12 (P ≤ 0.0001) concentrations, regardless of genotype. Conclusions: These data suggest that the TC 776C→G polymorphism negatively affects the serum holo-TC concentration and provide additional evidence that vitamin B-12 status modulates the homocysteine concentration in this population.

Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) are important for homocysteine remethylation. This study was designed to determine the influence of genetic variants (MTHFR 677C--T, MTHFR 1298A--C, and MTRR 66A--G), folate, and vitamin B-12 status on plasma homocysteine in women (20-30 y; n = 362). Plasma homocysteine was inversely (P0.0001) associated with serum folate and plasma vitamin B-12 regardless of genotype. Plasma homocysteine was higher (P0.05) for women with the MTHFR 677 TT/1298 AA genotype combination compared with the CC/AA, CC/AC, and CT/AA genotypes. Women with the MTHFR 677 TT/MTRR 66 AG genotype had higher (P0.05) plasma homocysteine than all other genotype combinations except the TT/AA and TT/GG genotypes. There were 5.4-, 4.3-, and 3.8-fold increases (P0.001) in risk for plasma homocysteine in the top 5, 10, and 20%, respectively, of the homocysteine distribution for subjects with the MTHFR 677 TT compared with the CC and CT genotypes. Predicted plasma homocysteine was inversely associated with serum folate (P = 0.003) and plasma vitamin B-12 (P = 0.002), with the degree of correlation dependent on MTHFR 677C--T genotype. These data suggest that coexistence of the MTHFR 677 TT genotype with the MTRR 66A--G polymorphism may exacerbate the effect of the MTHFR variant alone. The potential negative effect of combined polymorphisms of the MTHFR and MTRR genes on plasma homocysteine in at-risk population groups with low folate and/or vitamin B-12 status, such as women of reproductive potential, deserves further investigation.

DNA methylation is critical for normal genomic structure and function and is dependent on adequate folate status. A polymorphism (677C-->T) in a key folate enzyme, methylenetetrahydrofolate reductase (MTHFR), may impair DNA methylation when folate intake is inadequate and may increase the risk of reproductive abnormalities. The present study was designed to evaluate the effect of the MTHFR 677C-->T polymorphism on changes in global DNA methylation in young women consuming a low folate diet followed by repletion with the current Recommended Dietary Allowance (RDA). Women (age 20-30 years) with the TT (variant; n = 19) or CC (n = 22) genotype for the MTHFR 677C-->T polymorphism participated in a folate depletion-repletion study (7 weeks, 115 microg DFE/day; 7 weeks, 400 microg DFE/day). DNA methylation was measured at baseline, week 7, and week 14 using a [3H]methyl acceptance assay and a novel liquid chromatography tandem mass spectrometry assay of the DNA bases methylcytosine and cytosine. [3H]Methyl group acceptance tended to increase (P = 0.08) during depletion in all subjects, indicative of a decrease in global DNA methylation. During repletion, the raw change and the percent change in the methylcytosine/total cytosine ratio increased (P = 0.03 and P = 0.04, respectively) only in the subjects with the TT genotype. Moderate folate depletion in young women may cause a decrease in overall DNA methylation. The response to folate repletion suggests that following folate depletion women with the MTHFR 677 TT genotype have a greater increase in DNA methylation with folate repletion than women with the CC genotype.

This study was designed to evaluate the effect of the methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphism on folate and homocysteine response in nonHispanic women consuming a low folate diet followed by a diet providing the Recommended Dietary Allowance (RDA) for folate. Women (aged 20-30 y old) with either the TT (n = 19) or CC (n = 22) MTHFR 677C→T genotype participated in a folate depletion-repletion study (7 wk, 115 μg dietary folate equivalents (DFE)/d; 7 wk, 400 μg DFE/d). Overall serum folate decreased (P < 0.0001) during depletion and increased (P < 0.0001) during repletion with lower (P = 0.03) postdepletion serum folate in women with the TT versus CC genotype. Folate status was low (serum folate < 13.6 nmol/L) in more women with the TT (59%) compared with the CC genotype (15%) postdepletion. Red blood cell folate for all subjects decreased during depletion (P < 0.0001) and repletion (P = 0.02) with lower (P = 0.04) red blood cell folate in women with the TT compared with the CC genotype postrepletion. Homocysteine increased (P < 0.0001) for both genotype groups postdepletion and decreased (P = 0.02) postrepletion for the CC genotype group only. Homocysteine concentrations tended to be higher (P = 0.09) in the TT versus CC genotype group postdepletion and postrepletion. These data suggest that the MTHFR 677C→T polymorphism negatively affects the folate and homocysteine response in women consuming low folate diets followed by repletion with the RDA. These results may be important when evaluating the impact of the MTHFR 677C→T polymorphism in countries in which low folate diets are chronically consumed.

Methylenetetrahydrofolate reductase (MTHFR) polymorphisms may negatively influence one-carbon metabolism and increase health risks in women of reproductive age. The effect of MTHFR single nucleotide polymorphisms at bp 677 and/or 1298 and differences in folate and vitamin B-12 status on plasma homocysteine concentration in women of reproductive age (20-30 y; n = 186) were investigated. From the multivariate regression model, homozygotes (n = 23) for the C677T MTHFR variant had plasma homocysteine concentrations that were higher (P < 0.05) than those observed in the other 5 genotype groups, including those who were heterozygous for both variants (677CT/1298AC; n = 32). Plasma homocysteine was negatively associated with plasma vitamin B-12 concentration (P = 0.015) and serum folate (P = 0.049), with the degree of correlation between plasma vitamin B-12 and homocysteine concentrations dependent on MTHFR genotype. The C677T and A1298C MTHFR polymorphisms were significant predictors (P < 0.05) of plasma homocysteine when regression analysis was used to model plasma homocysteine concentration as a function of genotype, supplement use, serum folate and plasma vitamin B-12 concentration. Plasma homocysteine decreased as vitamin B-12 concentration increased (P = 0.0005) in individuals who were heterozygous for both the C677T and A1298C variants with nonsignificant trends (P = 0.114-0.128) in individuals homozygous for either the C677T or A1298C variants. In contrast, within the group of individuals with the wild-type genotype for both the C677T and A1298C MTHFR variants, homocysteine was not associated with changes in plasma vitamin B-12 concentrations. These data suggest that enhancing vitamin B-12 status may significantly decrease homocysteine in young women with C677T and/or A1298C MTHFR polymorphisms, even when vitamin B-12 concentrations are within the normal range.

Background: Folate-mediated one-carbon metabolism is essential for DNA synthesis, repair, and methylation. Perturbations in associated biomarkers have been implicated in increased risk of colorectal cancer. Inflammation, especially related to inflammatory bowel disease, is also implicated as a risk factor for colorectal cancer, and one-carbon nutrients, particularly vitamins B6 and B12, may directly affect inflammatory processes. A concurrent investigation of these two interrelated pathways could yield new information regarding relationships between inflammatory processes and one-carbon metabolism. Objective: To investigate correlations between nutritional, inflammatory, and one-carbon metabolism biomarkers. Methods: A cross-sectional study design was used to explore correlations between biomarkers of nutrition, inflammation and one-carbon metabolism in 1,976 women selected from the 93,676 participants in the Women's Health Initiative Observational Study. Nutritional biomarkers included vitamin B6 (pyridoxal-5'-phosphate [PLP]), vitamin B12, plasma folate, and red blood cell (RBC) folate. C-reactive protein (CRP) and serum amyloid A (SAA) were used as biomarkers of inflammation. Homocysteine and cysteine levels were measured as integrated biomarkers of one-carbon metabolism. All biomarkers were measured using established methods from samples obtained at baseline. SAS 9.2 was used to perform Student's t, Chi-squared, and Spearman rank correlation tests, along with multivariate linear regressions adjusted for age and body mass index (BMI), to explore the relationships between the biomarkers, with statistical significance at p Results: Plasma PLP was the only nutritional one-carbon metabolism biomarker to show significant inverse correlations with both CRP and SAA (r=-0.22, -0.12 respectively; p Conclusions: Biomarkers of inflammation are associated with concentrations of PLP, cysteine and homocysteine. While these associations between the biomarkers of inflammation, diet, and one-carbon metabolism are promising, determining causality is an important next step. Citation Format: Michael J. Paskow, Clare Abbenhardt, Joshua W. Miller, Xiaoling Song, Elissa C. Brown, Ting-Yuan David Cheng, Mark H. Wener, Yingye Zheng, Adetunji T. Toriola, Marian L. Neuhouser, Shirley A. A. Beresford, Karen Makar, Lynn B. Bailey, David R. Maneval, Ralph Green, JoAnn Manson, Linda Van Horn, Cornelia Ulrich. Relationships between biomarkers of diet, one-carbon metabolism, and inflammation within the Women's Health Initiative observational study. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr 34.

Folate is a source of one-carbons necessary for DNA methylation, a critical epigenetic modification necessary for genomic structure and function. The use of supplemental folic acid is widespread however; the potential influence on DNA methylation is unclear. We measured global DNA methylation using DNA extracted from samples from a population-based, double-blind randomized trial of folic acid supplementation (100, 400, 4000 µg per day) taken for 6 months; including a 3 month post-supplementation sample. We observed no changes in global DNA methylation in response to up to 4,000 µg/day for 6 months supplementation in DNA extracted from uncoagulated blood (approximates circulating blood). However, when DNA methylation was determined in coagulated samples from the same individuals at the same time, significant time, dose, and MTHFR genotype-dependent changes were observed. The baseline level of DNA methylation was the same for uncoagulated and coagulated samples; marked differences between sample types were observed only after intervention. In DNA from coagulated blood, DNA methylation decreased (−14%; P

Introduction: There is strong evidence that chronic inflammation plays a role in colorectal carcinogenesis. Despite this, epidemiological studies that have investigated this association using C-reactive protein (CRP) as an inflammatory biomarker have reported conflicting results, especially among women. Limitations of previous studies include the small number of cases and the fact that CRP measurements were performed at only one point in time. Likewise, no previous study has investigated the association of serum amyloid A (SAA), a related marker of inflammation, and colorectal cancer (CRC) risk. We investigated the associations of CRP and SAA with CRC risk, using repeat assessments, in a case-control study nested within the Women's Health Initiative Observational Study cohort (WHI-OS). We also explored the impact of changes in the two biomarkers (from baseline to 3rd year of follow-up) on CRC risk. Methods: The WHI-OS is a prospective cohort study that enrolled 93,676 post-menopausal women between 1993 and 1998 at 40 U.S. clinical institutions. We identified 988 women with CRC and matched 988 cancer-free control women based on age (±3 years), clinical center, race/ethnicity, and time of blood draw (±6 months). CRP and SAA measurements were performed at baseline and during the 3rd year of follow-up. Conditional logistic regression models were used to estimate the multivariate-adjusted odds ratios and 95% confidence intervals (OR, 95% CI) of CRC (adjusted for age, body mass index, post-menopausal hormone use (HRT) and previous history of colonoscopy). Results: Elevated CRP, but not SAA concentrations were positively associated with CRC risk. Women in the highest quintiles of CRP and SAA concentrations had an odds ratios of 1.28 (95% CI 0.94–1.76, p-trend=0.03) and 1.19 (95% CI 0.88–1.62, p-trend=0.17) respectively, compared to women in the lowest quintiles. Women who had high levels of both biomarkers had increased risk of colorectal cancer (OR=1.35, 95% CI 1.06–1.73, p-value=0.02), particularly colon cancer (OR=1.49, 95% CI 1.13–1.97, p-value=0.005) compared to those with low concentrations. Neither CRP nor SAA was positively associated with rectal cancer risk in any of the analyses. There was a non-significant increased risk of CRC (OR 1.31, 95% CI 0.91–1.89, p-trend=0.14) among women who had the largest increase in CRP concentration (from baseline to 3rd year of follow-up), while the risk associated with changes in SAA concentration was close to unity (OR 1.05 95% CI 0.73–1.49, p-trend 0.94). The associations between CRP and CRC risk were not modified by HRT use. Conclusions: Our study supports the hypothesis that inflammation is associated with colorectal carcinogenesis and that CRP and SAA used together may better predict CRC risk than either used alone. Citation Information: Cancer Prev Res 2011;4(10 Suppl):PR-05.

Introduction: The role of one-carbon metabolism related nutrients (folate, riboflavin (B2), B6, and B12) in colorectal carcinogenesis is still not fully understood. Folate and other B vitamins are essential for DNA methylation and repair and higher levels have been associated with a decreased risk for colorectal cancer (CRC) in some studies; however, non-linear relationships have been observed. We investigated the dietary intake of one-carbon nutrients and CRC risk in the WHI Observational Study, a large cohort of postmenopausal women. Methods: Dietary intake of folate and other B vitamins was determined via a Food Frequency Questionnaire and supplement inventory in 88,045 healthy women (aged 50 – 79 years, recruited between 1994 – 1998). Multivariate Cox proportional hazards regression models was used to estimate associations between nutrient intake and CRC risk and to evaluate differences in the associations by tumor site and stage. Hazard ratios (HR) for the 4th vs. 1st quartile were estimated. Results: In age-adjusted analyses significantly reduced risks for CRC were observed for the total (supplemental plus dietary) intake of folate (HR=0.82, 95%CI=0.68-0.97), vitamin B12 (HR=0.82, 0.69-0.99), vitamin B6 (HR=0.77, 0.65-0.92), and riboflavin (HR=0.75, 0.63-0.90). After multivariate adjustment (age, BMI, race, prior colonoscopy, smoking, physical activity, postmenopausal HT use) only the total intake of riboflavin (HR=0.80, 0.66-0.96) remained associated with a reduced risk for CRC. For the intake of vitamin B6 a borderline significance was observed (p=0.06, HR=0.85, 0.70-1.02). A site-specific observation was notable for supplemental and total riboflavin intake with a reduced risk for cancer of the distal colon (HRsupp=0.56, 0.33-0.96; HRtotal=0.69, 0.46-1.04) but not in proximal and rectal cancer. In regards to tumor stage, no significant difference was detected for localized and distant disease; the inverse association between the supplemental and total intake of riboflavin and vitamin B6 was limited to regionally spread disease (HRB2;supp=0.66, 0.45-0.96; HRB2;total=0.73, 0.54-0.99; HRB6;supp=0.69, 0.49-0.98; HRB6;total=0.72, 0.53-0.97). Conclusion: Higher riboflavin and vitamin B6 intake was linked to decreased risk for colorectal cancer in a large cohort of postmenopausal women, with some suggestion for stage- and site-specific associations. Our study provides limited support for an association of other B vitamins with CRC risk. (NIH R01 CA120523, N01WH22110) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1904. doi:10.1158/1538-7445.AM2011-1904

processes is still unresolved problem of economical sludge disposal. Pennsylvania, in one of its steps in seeking to find solutions to the minedrainage problem, has tackled the combined problem of mine-drainage abatement and water supply. Several projects supported by the state have been aimed at the regeneration of mine drainage for reuse. The various techniques that may be applied to mine-drainage demineralization include: evaporative processes, distillation processes, and membrane and ion-exchange processes. Flash distillation. On Feb. 1, 1965, the Coal Research Board, using coal-industry funds exclusively, issued a grant to the Westinghouse Electric Corp. to perform a feasibility study on the use of flash distillation for the processing of mine drainage. The results of this study indicate that there is every reason to believe that mine drainage can successfully be processed in a flash distillation unit. A second project was undertaken by the same corporation for the Coal Research Board. Under the terms of this grant, a pilot plant was constructed at Lester, Pa. At first, synthetic mine drainage was run through this plant; later, natural drainage was run. The plant processed up to 10,000 gal with a high degree of success. Concurrently with the study by Westinghouse of the engineering principles in designing a mobile stage flash-distillation unit, corrosion studies were conducted* These material studies indicated that titanium would hold up satisfactorily in the tube walls. The pilot-plant tubes therefore were constructed of this ma

Escherichia coli that exhibit the aggregative pattern of adherence to HEp-2 cells (enteroadherent-aggregative E. coli [EA-AggEC]) have been epidemiologically incriminated as a cause of diarrhea. We undertook a preliminary microbiological and pathogenetic characterization of 42 isolates of this putative pathogen. The strains were negative by tests with DNA probes for enteropathogenic, enterotoxigenic, enteroinvasive, and enterohemorrhagic E. coli and, by serotype, did not fit these categories. Thirty-nine of 42 strains had a 55-65-megadalton plasmid; many shared DNA homology. With one representative strain, plasmid transfer was accompanied by transfer of smooth lipopolysaccharide, fimbriae expression, and the aggregative property. EA-AggEC caused characteristic lesions in rabbit and rat ileal loops. The intestinal lesions and (Shiga-like) limb paralysis and death in rabbits inoculated with live organisms suggest toxin involvement; assays for Shiga-like toxins were negative. These preliminary results support the contention that EA-AggEC may represent a distinct category of diarrheagenic E. coli.