| 1. |
- Sonderby, Ida E., et al.
(författare)
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Dose response of the 16p11.2 distal copy number variant on intracranial volume and basal ganglia
- 2020
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Ingår i: Molecular Psychiatry. - : Nature Publishing Group. - 1359-4184 .- 1476-5578. ; 25:3, s. 584-602
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Tidskriftsartikel (refereegranskat)abstract
- Carriers of large recurrent copy number variants (CNVs) have a higher risk of developing neurodevelopmental disorders. The 16p11.2 distal CNV predisposes carriers to e.g., autism spectrum disorder and schizophrenia. We compared subcortical brain volumes of 12 16p11.2 distal deletion and 12 duplication carriers to 6882 non-carriers from the large-scale brain Magnetic Resonance Imaging collaboration, ENIGMA-CNV. After stringent CNV calling procedures, and standardized FreeSurfer image analysis, we found negative dose-response associations with copy number on intracranial volume and on regional caudate, pallidum and putamen volumes (β = −0.71 to −1.37; P < 0.0005). In an independent sample, consistent results were obtained, with significant effects in the pallidum (β = −0.95, P = 0.0042). The two data sets combined showed significant negative dose-response for the accumbens, caudate, pallidum, putamen and ICV (P = 0.0032, 8.9 × 10−6, 1.7 × 10−9, 3.5 × 10−12 and 1.0 × 10−4, respectively). Full scale IQ was lower in both deletion and duplication carriers compared to non-carriers. This is the first brain MRI study of the impact of the 16p11.2 distal CNV, and we demonstrate a specific effect on subcortical brain structures, suggesting a neuropathological pattern underlying the neurodevelopmental syndromes.
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| 2. |
- Eussen, Simone J. P. M., et al.
(författare)
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North-south gradients in plasma concentrations of B-vitamins and other components of one-carbon metabolism in Western Europe: results from the European Prospective Investigation into Cancer and Nutrition (EPIC) Study
- 2013
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Ingår i: British Journal of Nutrition. - 1475-2662 .- 0007-1145. ; 110:2, s. 363-374
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Tidskriftsartikel (refereegranskat)abstract
- Different lifestyle patterns across Europe may influence plasma concentrations of B-vitamins and one-carbon metabolites and their relation to chronic disease. Comparison of published data on one-carbon metabolites in Western European regions is difficult due to differences in sampling procedures and analytical methods between studies. The present study aimed, to compare plasma concentrations of one-carbon metabolites in Western European regions with one laboratory performing all biochemical analyses. We performed the present study in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort among 5446 presumptively healthy individuals. Quantile regression was used to compare sex-specific median concentrations between Northern (Denmark and Sweden), Central (France, Germany, The Netherlands and United Kingdom) and Southern (Greece, Spain and Italy) European regions. The lowest folate concentrations were observed in Northern Europe (men, 10.4 nmol/l; women, 10.7 nmol/l) and highest concentrations in Central Europe. Cobalamin concentrations were slightly higher in Northern Europe (men, 330 pmol/l; women, 352 pmol/l) compared with Central and Southern Europe, but did not show a clear north-south gradient. Vitamin B-2 concentrations were highest in Northern Europe (men, 22.2 nmol/l; women, 26.0 nmol/l) and decreased towards Southern Europe (P-trend < 0.001). Vitamin B-6 concentrations were highest in Central Europe in men (77.3 nmol/l) and highest in the North among women (70.4 nmol/l), with decreasing concentrations towards Southern Europe in women (P-trend < 0.001). In men, concentrations of serine, glycine and sarcosine increased from the north to south. In women, sarcosine increased from Northern to Southern Europe. These findings may provide relevant information for the study of regional differences of chronic disease incidence in association with lifestyle.
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| 3. |
- Fanidi, Anouar, et al.
(författare)
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Is high vitamin B12 status a cause of lung cancer?
- 2019
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 145:6, s. 1499-1503
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Tidskriftsartikel (refereegranskat)abstract
- Vitamin B supplementation can have side effects for human health, including cancer risk. We aimed to elucidate the role of vitamin B12 in lung cancer etiology via direct measurements of pre‐diagnostic circulating vitamin B12 concentrations in a nested case–control study, complemented with a Mendelian randomization (MR) approach in an independent case–control sample. We used pre‐diagnostic biomarker data from 5183 case–control pairs nested within 20 prospective cohorts, and genetic data from 29,266 cases and 56,450 controls. Exposures included directly measured circulating vitamin B12 in pre‐diagnostic blood samples from the nested case–control study, and 8 single nucleotide polymorphisms associated with vitamin B12 concentrations in the MR study. Our main outcome of interest was increased risk for lung cancer, overall and by histological subtype, per increase in circulating vitamin B12 concentrations. We found circulating vitamin B12 to be positively associated with overall lung cancer risk in a dose response fashion (odds ratio for a doubling in B12 [ORlog2B12] = 1.15, 95% confidence interval (95%CI) = 1.06–1.25). The MR analysis based on 8 genetic variants also indicated that genetically determined higher vitamin B12 concentrations were positively associated with overall lung cancer risk (OR per 150 pmol/L standard deviation increase in B12 [ORSD] = 1.08, 95%CI = 1.00–1.16). Considering the consistency of these two independent and complementary analyses, these findings support the hypothesis that high vitamin B12 status increases the risk of lung cancer.
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| 4. |
- Murphy, Michelle M, et al.
(författare)
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Longitudinal study of the effect of pregnancy on maternal and fetal cobalamin status in healthy women and their offspring.
- 2007
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Ingår i: Journal of Nutrition. - 0022-3166 .- 1541-6100. ; 137:8, s. 1863-1867
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Tidskriftsartikel (refereegranskat)abstract
- Compromised cobalamin status during pregnancy may put both mother and child at risk of deficiency during lactation and subsequent development. We investigated whether changes in cobalamin status during pregnancy are associated with impaired status in the mother and the cord. Plasma cobalamin, methylmalonic acid (MMA), and holotranscobalamin (holoTC) concentrations were determined in 92 women at preconception, 8, 20, and 32 wk of pregnancy, at labor, and in the cord. All variables [geometric mean percentiles 10, 90 (P(10), P(90))] were significantly reduced from preconception [cobalamin: 293 (155, 535) pmol/L; holoTC: 63 (38,98) pmol/L; MMA: 0.12 (0.09, 0.17) micromol/L] by 20 wk of pregnancy [cobalamin: 230 (123, 432) pmol/L; holoTC: 48 (34,78) pmol/L; MMA: 0.11 (0.08, 0.15) micromol/L P < 0.001]. Plasma cobalamin and holoTC remained lower throughout the remainder of pregnancy [32 wk: 198 (107, 339); labor: 224 (117, 444); P < 0.001] and [32 wk: 45 (26,82); labor: 40 (23,79); P < 0.05], respectively. By 32 wk, MMA was greater than preconception [0.14 (0.09, 0.20) micromol/L; P < 0.01]. Plasma holoTC at 32 wk and at labor was negatively correlated with cord MMA (r = -0.51, P < 0.001 and r = -0.40, P < 0.01, respectively). Women with lower holoTC at preconception had greater increases in MMA at 32 wk and at labor. Maternal MMA at 32 wk and at labor was significantly and independently associated with cord MMA only in women with lower holoTC at preconception (regression models: R(2) = 0.707, 0.682, respectively; P < 0.01). The moderate increases observed in the cobalamin biomarker, MMA, during pregnancy may indicate a functional depletion in intracellular cobalamin status.
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| 5. |
- Clarke, Robert, et al.
(författare)
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Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin.
- 2007
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Ingår i: Clinical Chemistry. - : Oxford University Press (OUP). - 0009-9147 .- 1530-8561. ; 53:5, s. 963-970
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Impaired vitamin B(12) function and decreased vitamin B(12) status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B(12) concentration, only a small percentage of which is metabolically active. Concentrations of this active component, carried on holotranscobalamin (holoTC), may be of greater relevance than total vitamin B(12). METHODS: We compared the utility of serum holoTC with conventional vitamin B(12) for detection of vitamin B(12) deficiency in a population-based study of older people, using increased methylmalonic acid (MMA) concentrations as a marker of metabolic vitamin B(12) deficiency in the overall population (n = 2403) and in subsets with normal (n = 1651) and abnormal (n = 752) renal function. RESULTS: Among all participants, 6% had definite (MMA >0.75 micromol/L) and 16% had probable (MMA >0.45 micromol/L) metabolic vitamin B(12) deficiency. In receiver operating characteristic curves for detection of definite vitamin B(12) deficiency, holoTC had a greater area under the curve (AUC) compared with vitamin B(12) in all participants (0.85 vs 0.76; P <0.001) and in subsets with normal (AUC: 0.87 vs 0.79; P <0.001) and abnormal (AUC: 0.85 vs 0.74; P = 0.002) renal function. Similar findings were observed for detection of moderate vitamin B(12) deficiency. Whereas the positive predictive value for both holoTC and vitamin B(12) was greater for detection of probable than definite vitamin B(12) deficiency, both tests were associated with more false-positive than true-positive test results. CONCLUSIONS: HoloTC has a modestly superior diagnostic accuracy compared with conventional vitamin B(12) for the detection of vitamin B(12) deficiency, but neither test can be recommended to screen asymptomatic populations.
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| 6. |
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| 7. |
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| 8. |
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| 9. |
- Riedel, Bettina M., et al.
(författare)
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Transcobalamin polymorphism 67A-> G, but not 776C-> G, affects serum holotranscobalamin in a cohort of healthy middle-aged men and women
- 2011
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Ingår i: Journal of Nutrition. - Bethesda, Md. : Elsevier BV. - 0022-3166 .- 1541-6100. ; 141:10, s. 1784-1790
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Tidskriftsartikel (refereegranskat)abstract
- Two polymorphic variants in the gene coding for transcobalamin II (TCN2), TCN2 776C-> G and TCN2 67A-> G, may alter serum holotranscobalamin (holoTC), which in turn may affect cellular uptake of cobalamin (Cbl) and thereby Cbl status indicators. We studied the effects of TCN2 776C- > G and TCN2 67A- > G on blood concentrations of holoTC, Cbl, methylmalonic acid (MMA), and total homocysteine (tHcy) in 2411 individuals (50-64 y) that had been selected on the basis of these TCN2 genotypes from 10601 Norwegian inhabitants. The serum holoTC concentration was lower in TCN2 67AG (55 +/- 0.75 pmol/L) and 67GG (48 +/- 2.14 pmol/L) than in 67AA (62 +/- 0.67 pmol/L) (P < 0.001) but did not differ among TCN2 776C-> G genotypes. The polymorphisms interacted as serum holoTC determinants (P= 0.001) and the presence of TCN2 67AG and GG in strata of 776CC and CG, but not 776GG, increased the risk of having serum holoTC <45.6 pmol/L [tertile 1 vs. tertiles 2 and 3: OR = 2.5(95% CI 1.8-3.5) for 67AG; OR = 5.7 (95% Cl 3.5-9.1) for 67GG in 776CC; OR = 2.1 195% Cl 1.6-2.9) for 67AG; and OR = 4.5 (95% Cl 2.4-8.2) for 67GG in 776CG; all P < 0.0011. Plasma MMA, tHcy, and Cbl were not affected by either polymorphism. In summary, serum holoTC, but not plasma Cbl, MMA, or tHcy, varied according to TCN2 67A-> G genotypes. It remains to be determined whether this polymorphic effect on serum holoTC alters its diagnostic utility as Cbl status indicator.
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| 10. |
- Theofylaktopoulou, Despoina, et al.
(författare)
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Impaired functional vitamin B6 status is associated with increased risk of lung cancer
- 2018
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 142:12, s. 2425-2434
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Tidskriftsartikel (refereegranskat)abstract
- Circulating vitamin B6 levels have been found to be inversely associated with lung cancer. Most studies have focused on the B6 form pyridoxal 5'-phosphate (PLP), a direct biomarker influenced by inflammation and other factors. Using a functional B6 marker allows further investigation of the potential role of vitamin B6 status in the pathogenesis of lung cancer. We prospectively evaluated the association of the functional marker of vitamin B6 status, the 3-hydroxykynurenine:xanthurenic acid (HK:XA) ratio, with risk of lung cancer in a nested case-control study consisting of 5,364 matched case-control pairs from the Lung Cancer Cohort Consortium (LC3). We used conditional logistic regression to evaluate the association between HK:XA and lung cancer, and random effect models to combine results from different cohorts and regions. High levels of HK:XA, indicating impaired functional B6 status, were associated with an increased risk of lung cancer, the odds ratio comparing the fourth and the first quartiles (OR4th vs. 1st) was 1.25 (95% confidence interval, 1.10-1.41). Stratified analyses indicated that this association was primarily driven by cases diagnosed with squamous cell carcinoma. Notably, the risk associated with HK:XA was approximately 50% higher in groups with a high relative frequency of squamous cell carcinoma, i.e., men, former and current smokers. This risk of squamous cell carcinoma was present in both men and women regardless of smoking status.
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| 11. |
- Fanidi, Anouar, et al.
(författare)
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Circulating Folate, Vitamin B6, and Methionine in Relation to Lung Cancer Risk in the Lung Cancer Cohort Consortium (LC3)
- 2018
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 110:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Circulating concentrations of B vitamins and factors related to one-carbon metabolism have been found to be strongly inversely associated with lung cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The extent to which these associations are present in other study populations is unknown.Methods: Within 20 prospective cohorts from the National Cancer Institute Cohort Consortium, a nested case-control study was designed including 5364 incident lung cancer case patients and 5364 control subjects who were individually matched to case patients by age, sex, cohort, and smoking status. Centralized biochemical analyses were performed to measure circulating concentrations of vitamin B6, folate, and methionine, as well as cotinine as an indicator of recent tobacco exposure. The association between these biomarkers and lung cancer risk was evaluated using conditional logistic regression models.Results: Participants with higher circulating concentrations of vitamin B6 and folate had a modestly decreased risk of lung cancer risk overall, the odds ratios when comparing the top and bottom fourths (OR 4vs1 ) being 0.88 (95% confidence interval [CI] = 0.78 to 1.00) and 0.86 (95% CI = 0.74 to 0.99), respectively. We found stronger associations among men (vitamin B6: OR 4vs1 = 0.74, 95% CI = 0.62 to 0.89; folate: OR 4vs1 = 0.75, 95% CI = 0.61 to 0.93) and ever smokers (vitamin B6: OR 4vs1 = 0.78, 95% CI = 0.67 to 0.91; folate: OR 4vs1 = 0.87, 95% CI = 0.73 to 1.03). We further noted that the association of folate was restricted to Europe/Australia and Asia, whereas no clear association was observed for the United States. Circulating concentrations of methionine were not associated with lung cancer risk overall or in important subgroups.Conclusions: Although confounding by tobacco exposure or reverse causation cannot be ruled out, these study results are compatible with a small decrease in lung cancer risk in ever smokers who avoid low concentrations of circulating folate and vitamin B6.
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| 12. |
- Huang, Joyce Y., et al.
(författare)
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Circulating markers of cellular immune activation in prediagnostic blood sample and lung cancer risk in the Lung Cancer Cohort Consortium (LC3)
- 2020
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 146:9, s. 2394-2405
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Tidskriftsartikel (refereegranskat)abstract
- Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all p(trend) < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.
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| 13. |
- Johansson, Mattias, et al.
(författare)
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Serum B vitamin levels and risk of lung cancer
- 2010
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Ingår i: Journal of the American Medical Association (JAMA). - : American Medical Association. - 0098-7484 .- 1538-3598. ; 303:23, s. 2377-2385
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: B vitamins and factors related to 1-carbon metabolism help to maintain DNA integrity and regulate gene expression and may affect cancer risk. OBJECTIVE: To investigate if 1-carbon metabolism factors are associated with onset of lung cancer. DESIGN, SETTING, AND PARTICIPANTS: The European Prospective Investigation into Cancer and Nutrition (EPIC) recruited 519,978 participants from 10 countries between 1992 and 2000, of whom 385,747 donated blood. By 2006, 899 lung cancer cases were identified and 1770 control participants were individually matched by country, sex, date of birth, and date of blood collection. Serum levels were measured for 6 factors of 1-carbon metabolism and cotinine. MAIN OUTCOME MEASURE: Odds ratios (ORs) of lung cancer by serum levels of 4 B vitamins (B(2), B(6), folate [B(9)], and B(12)), methionine, and homocysteine. RESULTS: Within the entire EPIC cohort, the age-standardized incidence rates of lung cancer (standardized to the world population, aged 35-79 years) were 6.6, 44.9, and 156.1 per 100,000 person-years among never, former, and current smokers for men, respectively. The corresponding incidence rates for women were 7.1, 23.9, and 100.9 per 100,000 person-years, respectively. After accounting for smoking, a lower risk for lung cancer was seen for elevated serum levels of B(6) (fourth vs first quartile OR, 0.44; 95% confidence interval [CI], 0.33-0.60; P for trend <.000001), as well as for serum methionine (fourth vs first quartile OR, 0.52; 95% CI, 0.39-0.69; P for trend <.000001). Similar and consistent decreases in risk were observed in never, former, and current smokers, indicating that results were not due to confounding by smoking. The magnitude of risk was also constant with increasing length of follow-up, indicating that the associations were not explained by preclinical disease. A lower risk was also seen for serum folate (fourth vs first quartile OR, 0.68; 95% CI, 0.51-0.90; P for trend = .001), although this was apparent only for former and current smokers. When participants were classified by median levels of serum methionine and B(6), having above-median levels of both was associated with a lower lung cancer risk overall (OR, 0.41; 95% CI, 0.31-0.54), as well as separately among never (OR, 0.36; 95% CI, 0.18-0.72), former (OR, 0.51; 95% CI, 0.34-0.76), and current smokers (OR, 0.42; 95% CI, 0.27-0.65). CONCLUSION: Serum levels of vitamin B(6) and methionine were inversely associated with risk of lung cancer.
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| 14. |
- Midttun, Oivind, et al.
(författare)
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Circulating concentrations of biomarkers and metabolites related to vitamin status, one-carbon and the kynurenine pathways in US, Nordic, Asian, and Australian populations
- 2017
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Ingår i: American Journal of Clinical Nutrition. - : AMER SOC NUTRITION-ASN. - 0002-9165 .- 1938-3207. ; 105:6, s. 1314-1326
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Tidskriftsartikel (refereegranskat)abstract
- Background: Circulating concentrations of biomarkers that are related to vitamin status vary by factors such as diet, fortification, and supplement use. Published biomarker concentrations have also been influenced by the variation across laboratories, which complicates a comparison of results from different studies. Objective: We robustly and comprehensively assessed differences in biomarkers that are related to vitamin status across geographic regions. Design: The trial was a cross-sectional study in which we investigated 38 biomarkers that are related to vitamin status and one-carbon and tryptophan metabolism in serum and plasma from 5314 healthy control subjects representing 20 cohorts recruited from the United States, Nordic countries, Asia, and Australia, participating in the Lung Cancer Cohort Consortium. All samples were analyzed in a centralized laboratory. Results: Circulating concentrations of riboflavin, pyridoxal 5'-phosphate, folate, vitamin B-12, all-trans retinol, 25-hydroxyvitamin D, and a-tocopherol as well as combined vitamin scores that were based on these nutrients showed that the general B-vitamin concentration was highest in the United States and that the B vitamins and lipid soluble vitamins were low in Asians. Conversely, circulating concentrations of metabolites that are inversely related to B vitamins involved in the one-carbon and kynurenine pathways were high in Asians. The high B-vitamin concentration in the United States appears to be driven mainly by multivitamin-supplement users. Conclusions: The observed differences likely reflect the variation in intake of vitamins and, in particular, the widespread multivitamin-supplement use in the United States. The results provide valuable information about the differences in biomarker concentrations in populations across continents.
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| 15. |
- Nilsen, M. S., et al.
(författare)
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3-Hydroxyisobutyrate, A Strong Marker of Insulin Resistance in Type 2 Diabetes and Obesity That Modulates White and Brown Adipocyte Metabolism
- 2020
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 69:9, s. 1903-1916
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Tidskriftsartikel (refereegranskat)abstract
- Circulating branched-chain amino acids (BCAAs) associate with insulin resistance and type 2 diabetes. 3-Hydroxyisobutyrate (3-HIB) is a catabolic intermediate of the BCAA valine. In this study, we show that in a cohort of 4,942 men and women, circulating 3-HIB is elevated according to levels of hyperglycemia and established type 2 diabetes. In complementary cohorts with measures of insulin resistance, we found positive correlates for circulating 3-HIB concentrations with HOMA2 of insulin resistance, as well as a transient increase in 3-HIB followed by a marked decrease after bariatric surgery and weight loss. During differentiation, both white and brown adipocytes upregulate BCAA utilization and release increasing amounts of 3-HIB. Knockdown of the 3-HIB-forming enzyme 3-hydroxyisobutyryl-CoA hydrolase decreases release of 3-HIB and lipid accumulation in both cell types. Conversely, addition of 3-HIB to white and brown adipocyte cultures increases fatty acid uptake and modulated insulin-stimulated glucose uptake in a time-dependent manner. Finally, 3-HIB treatment decreases mitochondrial oxygen consumption and generation of reactive oxygen species in white adipocytes, while increasing these measures in brown adipocytes. Our data establish 3-HIB as a novel adipocyte-derived regulator of adipocyte subtype-specific functions strongly linked to obesity, insulin resistance, and type 2 diabetes.
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| 16. |
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| 17. |
- Ueland, Grethe Å., et al.
(författare)
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The Short Cosyntropin Test Revisited : New Normal Reference Range Using LC-MS/MS
- 2018
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Oxford University Press. - 0021-972X .- 1945-7197. ; 103:4, s. 1696-1703
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Tidskriftsartikel (refereegranskat)abstract
- Background: The cosyntropin test is used to diagnose adrenal insufficiency (AI) and nonclassical congenital adrenal hyperplasia (NCCAH). Current cutoffs for cortisol and 17-hydroxyprogesterone (17-OHP) are derived from nonstandardized immunoassays. Liquid chromatography tandem mass spectrometry (LC-MS/MS) offers direct measurement of steroids, prompting the need to re-establish normal ranges. Objective: The goal of this study was to define cutoff values for cortisol and 17-OHP in serum by LC-MS/MS 30 and 60 minutes after intravenous administration of 250 µg tetracosactide acetate to healthy volunteers and to compare the results with LC-MS/MS with routine immunoassays. Methods: Cosyntropin testing was performed in healthy subjects (n = 138) and in patients referred for evaluation of adrenocortical function (n = 94). Steroids were assayed by LC-MS/MS and compared with two immunoassays used in routine diagnostics (Immulite and Roche platforms). The cutoff level for cortisol was defined as the 2.5% percentile in healthy subjects not using oral estrogens (n = 121) and for 17-OHP as the 97.5% percentile. Results: Cortisol cutoff levels for LC-MS/MS were 412 and 485 nmol/L at 30 and 60 minutes, respectively. Applying the new cutoffs, 13 of 60 (22%) subjects who had AI according to conventional criteria now had a normal test result. For 17-OHP, the cutoff levels were 8.9 and 9.0 nmol/L at 30 and 60 minutes, respectively. Conclusions: LC-MS/MS provides cutoff levels for cortisol and 17-OHP after cosyntropin stimulation that are lower than those based on immunoassays, possibly because cross-reactivity between steroid intermediates and cortisol is eliminated. This reduces the number of false-positive tests for AI and false-negative tests for NCCAH.
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| 18. |
- Aleksandrova, Krasimira, et al.
(författare)
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A prospective study of the immune system activation biomarker neopterin and colorectal cancer risk
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 107:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Neopterin may be relevant for colorectal cancer (CRC) development, as a biomarker of cellular immune activity exerting pleiotropic effects on cellular ageing, oxidative stress, and inflammation. So far, the association between prediagnostic neopterin and colon and rectal cancer risk has not been evaluated in human populations. Methods: A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition cohort using data on plasma concentrations of total neopterin (T-N, sum of neopterin and 7,8-dihydroneopterin) in 830 incident CRC case patients (561 colon and 269 rectal) matched within risk sets to 830 control participants. A subsequent replication study used data from the Hordaland Health Study, where 173 CRC case patients have been diagnosed among 6594 healthy participants over 12 years of follow-up. Results: After multivariable adjustment for a priori chosen CRC risk factors, a "U-shaped" association of T-N with CRC was revealed. Compared with the second quintile of the T-N distribution, the relative risks for the first, third, fourth, and fifth quintiles were 2.37 (95% CI = 1.66 to 3.39), 1.24 (95% CI = 0.87 to 1.77), 1.55 (95% CI = 1.08 to 2.22), and 2.31 (95% CI = 1.63 to 3.27), respectively. Replication of these associations within the Hordaland Health Study yielded similar results. No differences have been observed when the associations were explored by colon and rectal cancer site (two-sided P-difference = .87) and after excluding case patients diagnosed within the first four follow-up years. Conclusions: These novel findings provide evidence of the role of both suppressed and activated cell-mediated immunity as reflected by prediagnostic T-N concentrations in the development of CRC.
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| 19. |
- Baltar, Valéria Troncoso, et al.
(författare)
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Smoking, secondhand smoke, and cotinine levels in a subset of EPIC cohort
- 2011
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 20:5, s. 869-875
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Tidskriftsartikel (refereegranskat)abstract
- Background: Several countries are discussing new legislation regarding the ban on smoking in public places, based on the growing evidence of the hazards of secondhand smoke (SHS) exposure. The objective of the present study is to quantitatively assess the relationship between smoking, SHS, and serum cotinine levels in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: From a study on lung cancer in the EPIC cohort, questionnaire information on smoking was collected at enrolment, and cotinine was measured in serum. Three statistical models were applied by using samples available in a cross-section design: (i) cotinine levels by categories combining smoking and SHS (n = 859); (ii) the effect of hours of passive smoking exposure in nonsmokers only (n = 107); (iii) the effect of the number of cigarettes consumed per day in current smokers only (n = 832). All models were adjusted for country, sex, age, and body mass index. Results: Among nonsmokers, passive smokers presented significant differences in cotinine compared with nonexposed, with a marked (but not significant) difference among former-smokers. A one hour per day increment of SHS gave rise to a significant 2.58 nmol/L (0.45 ng/mL) increase in mean serum cotinine (P < 0.001). In current smokers, a one cigarette per day increment gave rise to a significant 22.44 nmol/L (3.95 ng/mL) increase in cotinine mean (P < 0.001). Conclusions: There is clear evidence that not only tobacco smoking but also involuntary exposure increases cotinine levels. Impact: This study strengthens the evidence for the benefits of a smoking ban in public places.
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| 20. |
- Chandyo, Ram K., et al.
(författare)
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Nutritional Intake and Status of Cobalamin and Folate among Non-Pregnant Women of Reproductive Age in Bhaktapur, Nepal
- 2016
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643. ; 8:6
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Tidskriftsartikel (refereegranskat)abstract
- Cobalamin and folate are especially important for women of childbearing age due to their ubiquitous role in fetal growth and development. Population-based data on cobalamin and folate status are lacking from Nepal, where diets are mostly vegetarian. The objectives of the study were to investigate cobalamin and folate intake and status, and to explore associations with socio-demographics, anthropometrics, anemia, and dietary habits. Following a random selection of geographical clusters, we collected blood samples from 500 non-pregnant women and 24-h dietary recalls and food frequency questionnaires from a subsample of 379 women. Twenty percent of the women did not consume any food containing cobalamin during the days recalled, and in 72% nutritional cobalamin intake was <1 mu g/day. Eighty-four percent of the women had cobalamin intake lower than the estimated average requirement (EAR) (< 2 mu g/day). In contrast, only 12% of the women had a folate intake less than 100 mu g per day, whereas 62% had intake between 100 and 320 mu g. Low plasma cobalamin (< 150 pmol/L) was found in 42% of the women, most of whom (88%) also had elevated levels of methylmalonic acid. Our results indicated a high prevalence of nutritional cobalamin deficiency, while folate deficiency was uncommon.
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| 21. |
- Chuang, Shu-Chun, et al.
(författare)
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A U-shaped relationship between plasma folate and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition
- 2011
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Ingår i: European Journal of Cancer. - Oxford : Pergamon. - 0959-8049 .- 1879-0852. ; 47:12, s. 1808-1816
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Tidskriftsartikel (refereegranskat)abstract
- Folate intake has shown an inverse association with pancreatic cancer; nevertheless, results from plasma measurements were inconsistent. The aim of this study is to examine the association between plasma total homocysteine, methionine, folate, cobalamin, pyridoxal 5'-phosphate, riboflavin, flavin mononucleotide and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC). We conducted a nested case-control study in the EPIC cohort, which has an average of 9.6 years of follow-up (1992-2006), using 463 incident pancreatic cancer cases. Controls were matched to each case by center, sex, age (+/- 1 year), date (+/- 1 year) and time (+/- 3 h) at blood collection and fasting status. Conditional logistic regression was used to calculate the odds ratios (OR) and 95% confidence intervals (CI), adjusting for education, smoking status, plasma cotinine concentration, alcohol drinking, body mass index and diabetes status. We observed a U-shaped association between plasma folate and pancreatic cancer risk. The ORs for plasma folate <= 5, 5-10, 10-15 (reference), 15-20, and > 20 nmol/L were 1.58 (95% CI = 0.72-3.46), 1.39 (0.93-2.08), 1.0 (reference), 0.79 (0.52-1.21), and 1.34 (0.89-2.02), respectively. Methionine was associated with an increased risk in men (per quintile increment: OR = 1.17, 95% CI = 1.00-1.38) but not in women (OR = 0.91, 95% CI = 0.78-1.07; p for heterogeneity < 0.01). Our results suggest a U-shaped association between plasma folate and pancreatic cancer risk in both men and women. The positive association that we observed between methionine and pancreatic cancer may be sex dependent and may differ by time of follow-up. However, the mechanisms behind the observed associations warrant further investigation.
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| 22. |
- Chuang, Shu-Chun, et al.
(författare)
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Circulating Biomarkers of Tryptophan and the Kynurenine Pathway and Lung Cancer Risk
- 2014
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 23:3, s. 461-468
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Tidskriftsartikel (refereegranskat)abstract
- Background: Imbalances in tryptophan metabolism have been linked to cancer-related immune escape and implicated in several cancers, including lung cancer. Methods: We conducted a nested case-control study within the European Prospective Investigation into Cancer andNutrition (EPIC) that included 893 incident lung cancer cases and 1,748matched controls. Circulating levels of tryptophan and six of its metabolites were measured and evaluated in relation to lung cancer risk. Results: Tryptophan (P-trend = 2 Chi 10(-5)) and the kynurenine/ tryptophan ratio (KTR; P-trend 4 Chi 10(-5)) were associated with lung cancer risk overall after adjusting for established risk factors. The ORs comparing the fifth and first quintiles (OR5th (vs. 1st)) were 0.52 [ 95% confidence interval (CI), 0.37-0.74] for tryptophan and 1.74 (95% CI, 1.24-2.45) for KTR. After adjusting for plasma methionine (available fromprevious work, which was strongly correlated with tryptophan), the associations of tryptophan (adjusted P-trend 0.13) and KTR (P-trend = 0.009) were substantially attenuated. KTR was positively associated with squamous cell carcinoma, the OR5th vs. 1st being 2.83 (95% CI, 1.62-4.94, P-trend -3 Chi 10(-5)) that was only marginally affected by adjusting for methionine. Conclusions: This study indicates that biomarkers of tryptophan metabolism are associated with subsequent lung cancer risk. Although this result would seem consistent with the immune system having a role in lung cancer development, the overall associations were dependent on methionine, and further studies are warranted to further elucidate the importance of these metabolites in lung cancer etiology. Impact: This is the first prospective study investigating the tryptophan pathway in relation to lung cancer risk.
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| 23. |
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| 24. |
- Gylling, Björn, et al.
(författare)
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Vitamin B-6 and colorectal cancer risk : a prospective population-based study using 3 distinct plasma markers of vitamin B-6 status
- 2017
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 105:4, s. 897-904
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Tidskriftsartikel (refereegranskat)abstract
- Background: Higher plasma concentrations of the vitamin B-6 marker pyridoxal 5#-phosphate (PLP) have been associated with reduced colorectal cancer (CRC) risk. Inflammatory processes, including vitamin B-6 catabolism, could explain such findings. Objective: We investigated 3 biomarkers of vitamin B-6 status in relation to CRC risk. Design: This was a prospective case-control study of 613 CRC cases and 1190 matched controls nested within the Northern Sweden Health and Disease Study (n = 114,679). Participants were followed from 1985 to 2009, and the median follow-up from baseline to CRC diagnosis was 8.2 y. PLP, pyridoxal, pyridoxic acid (PA), 3-hydroxykynurenine, and xanthurenic acids (XAs) were measured in plasma with the use of liquid chromatography-tandem mass spectrometry. We calculated relative and absolute risks of CRC for PLP and the ratios 3-hydroxykynurenine: XA (HK: XA), an inverse marker of functional vitamin B-6 status, and PA:(PLP + pyridoxal) (PAr), a marker of inflammation and oxidative stress and an inverse marker of vitamin B-6 status. Results: Plasma PLP concentrations were associated with a reduced CRC risk for the third compared with the first quartile and for PLP sufficiency compared with deficiency [OR: 0.60 (95% CI: 0.44, 0.81) and OR: 0.55 (95% CI: 0.37, 0.81), respectively]. HK: XA and PAr were both associated with increased CRC risk [OR: 1.48 (95% CI: 1.08, 2.02) and OR: 1.50 (95% CI: 1.10, 2.04), respectively] for the fourth compared with the first quartile. For HK: XA and PAr, the findings were mainly observed in study participants with,10.5 y of follow-up between sampling and diagnosis. Conclusions: Vitamin B-6 deficiency as measured by plasma PLP is associated with a clear increase in CRC risk. Furthermore, our analyses of novel markers of functional vitamin B-6 status and vitamin B-6-associated oxidative stress and inflammation suggest a role in tumor progression rather than initiation.
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| 25. |
- Hin, Harold, et al.
(författare)
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Clinical relevance of low serum vitamin B12 concentrations in older people : the Banbury B12 study
- 2006
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Ingår i: Age and Ageing. - London : Oxford University Press. - 0002-0729 .- 1468-2834. ; 35:4, s. 416-422
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Tidskriftsartikel (refereegranskat)abstract
- Background: low vitamin B12 concentrations are common in older people, but the clinical relevance of biochemical evidence of vitamin B12 deficiency in the absence of anaemia is uncertain. Objective: to examine associations of cognitive impairment, depression and neuropathy with blood measurements of vitamin B12 and folate status in older people. Design: cross-sectional study in general practice in Banbury, England. Participants: a total of 1,000 individuals aged 75 years or older living in the community. Results: low vitamin B12 concentrations were identified in 13% of older people and were associated with memory impairment and depression. After adjustment for age, sex and smoking, individuals with vitamin B12 or holotranscobalamin (holoTC) in the bottom compared with top quartiles had a 2-fold risk (OR = 2.17; 95% CI 1.11-4.27) and a 3-fold risk (OR = 3.02; 95% CI 1.31-6.98) of cognitive impairment, respectively. Low vitamin B12 status was also associated with missing ankle tendon jerks but not with depression. Treatment with vitamin B12 for 3 months corrected the biochemical abnormalities but had no effect on any of the clinical measurements. Conclusions: low vitamin B12 concentrations are associated with cognitive impairment and missing ankle tendon jerks in older people in the absence of anaemia. Large-scale trials of vitamin B12 supplementation are required to assess the clinical significance of these associations.
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