Henk J Blom

Summary

Affiliation: Radboud University Nijmegen Medical Centre
Country: The Netherlands

Publications

  1. pmc Neural tube defects and folate: case far from closed
    Henk J Blom
    Laboratory of Pediatrics and Neurology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Post Office Box 9101, 6500 HB Nijmegen, The Netherlands
    Nat Rev Neurosci 7:724-31. 2006
  2. ncbi request reprint Catechol-O-methyltransferase genotype is associated with plasma total homocysteine levels and may increase venous thrombosis risk
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Thromb Haemost 98:1226-31. 2007
  3. ncbi request reprint MTRR 66A>G polymorphism in relation to congenital heart defects
    Ingrid M van Beynum
    Children s Heart Centre, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Clin Chem Lab Med 44:1317-23. 2006
  4. ncbi request reprint Low vitamin B6, and not plasma homocysteine concentration, as risk factor for abdominal aortic aneurysm: a retrospective case-control study
    Anita C Peeters
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    J Vasc Surg 45:701-5. 2007
  5. ncbi request reprint Marfanoid features in a child with combined methylmalonic aciduria and homocystinuria (CblC type)
    Sandra G Heil
    Department of Pediatrics, Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, P O Box 9101, 6500 HB, Nijmegen, The Netherlands
    J Inherit Metab Dis 30:811. 2007
  6. ncbi request reprint No interaction between factor V Leiden and hyperhomocysteinemia or MTHFR 677TT genotype in venous thrombosis. Results of a meta-analysis of published studies and a large case-only study
    Miranda B A J Keijzer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Geert Grooteplein 8, 6525 GA Nijmegen, P O Box 9101, 6500 HB Nijmegen, The Netherlands
    Thromb Haemost 97:32-7. 2007
  7. ncbi request reprint Low fasting methionine concentration as a novel risk factor for recurrent venous thrombosis
    Miranda B A J Keijzer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Thromb Haemost 96:492-7. 2006
  8. ncbi request reprint Homocysteine lowering by B vitamins and the secondary prevention of deep vein thrombosis and pulmonary embolism: A randomized, placebo-controlled, double-blind trial
    Martin den Heijer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    Blood 109:139-44. 2007
  9. ncbi request reprint Gene-gene interaction between the cystathionine beta-synthase 31 base pair variable number of tandem repeats and the methylenetetrahydrofolate reductase 677C > T polymorphism on homocysteine levels and risk for neural tube defects
    Lydia A Afman
    University Medical Center Nijmegen, Department of Pediatrics, Laboratory of Pediatrics and Neurology, PO Box 9101, 6500 HB Nijmegen, Netherlands
    Mol Genet Metab 78:211-5. 2003
  10. ncbi request reprint Cystathionine beta-synthase polymorphisms and hyperhomocysteinaemia: an association study
    Karin J A Lievers
    Laboratory of Pediatrics and Neurology, University Medical Center Nijmegen, The Netherlands
    Eur J Hum Genet 11:23-9. 2003

Detail Information

Publications72

  1. pmc Neural tube defects and folate: case far from closed
    Henk J Blom
    Laboratory of Pediatrics and Neurology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Post Office Box 9101, 6500 HB Nijmegen, The Netherlands
    Nat Rev Neurosci 7:724-31. 2006
    ..Exploring the methylation hypothesis could direct us towards additional strategies to prevent neural tube defects...
  2. ncbi request reprint Catechol-O-methyltransferase genotype is associated with plasma total homocysteine levels and may increase venous thrombosis risk
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Thromb Haemost 98:1226-31. 2007
    ..61 [95% CI 0.97 to 2.65], p = 0.06) compared to control subjects. We show that the COMT rs4680 variant modulates tHcy, and might be associated with venous thrombosis risk as well...
  3. ncbi request reprint MTRR 66A>G polymorphism in relation to congenital heart defects
    Ingrid M van Beynum
    Children s Heart Centre, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Clin Chem Lab Med 44:1317-23. 2006
    ..In addition, possible interaction between this variant and plasma methylmalonic acid (MMA) concentrations, as an indicator of intracellular vitamin B(12) status, was investigated...
  4. ncbi request reprint Low vitamin B6, and not plasma homocysteine concentration, as risk factor for abdominal aortic aneurysm: a retrospective case-control study
    Anita C Peeters
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    J Vasc Surg 45:701-5. 2007
    ....
  5. ncbi request reprint Marfanoid features in a child with combined methylmalonic aciduria and homocystinuria (CblC type)
    Sandra G Heil
    Department of Pediatrics, Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, P O Box 9101, 6500 HB, Nijmegen, The Netherlands
    J Inherit Metab Dis 30:811. 2007
    ....
  6. ncbi request reprint No interaction between factor V Leiden and hyperhomocysteinemia or MTHFR 677TT genotype in venous thrombosis. Results of a meta-analysis of published studies and a large case-only study
    Miranda B A J Keijzer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Geert Grooteplein 8, 6525 GA Nijmegen, P O Box 9101, 6500 HB Nijmegen, The Netherlands
    Thromb Haemost 97:32-7. 2007
    ..23 (95%CI 0.72 to 2.11). Both the meta-analyses of published studies and a large case-only study did not show evidence for interaction between factor V Leiden and hyperhomocysteinemia for risk of venous thrombosis...
  7. ncbi request reprint Low fasting methionine concentration as a novel risk factor for recurrent venous thrombosis
    Miranda B A J Keijzer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Thromb Haemost 96:492-7. 2006
    ..This risk association was stronger for methionine than for homocysteine or cysteine. This supports the hypothesis that impaired methylation may be involved in the pathogenesis of venous thrombosis...
  8. ncbi request reprint Homocysteine lowering by B vitamins and the secondary prevention of deep vein thrombosis and pulmonary embolism: A randomized, placebo-controlled, double-blind trial
    Martin den Heijer
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    Blood 109:139-44. 2007
    ..65-1.98) in the hyperhomocysteinemic group and 0.58 (95% CI, 0.31-1.07) in the normohomocysteinemic group. The results of our study do not show that homocysteine lowering by B vitamin supplementation prevents recurrent venous thrombosis...
  9. ncbi request reprint Gene-gene interaction between the cystathionine beta-synthase 31 base pair variable number of tandem repeats and the methylenetetrahydrofolate reductase 677C > T polymorphism on homocysteine levels and risk for neural tube defects
    Lydia A Afman
    University Medical Center Nijmegen, Department of Pediatrics, Laboratory of Pediatrics and Neurology, PO Box 9101, 6500 HB Nijmegen, Netherlands
    Mol Genet Metab 78:211-5. 2003
    ..Recently, our group showed that a 31 bp VNTR in the CBS gene was associated with decreased CBS activity and increased tHcy levels after methionine loading in a CVD population...
  10. ncbi request reprint Cystathionine beta-synthase polymorphisms and hyperhomocysteinaemia: an association study
    Karin J A Lievers
    Laboratory of Pediatrics and Neurology, University Medical Center Nijmegen, The Netherlands
    Eur J Hum Genet 11:23-9. 2003
    ..In conclusion, we did not find any indication that genetic variation in the CBS gene is associated with increased homocysteine concentrations...
  11. ncbi request reprint Association of a 31 bp VNTR in the CBS gene with postload homocysteine concentrations in the Framingham Offspring Study
    Karin J A Lievers
    Department of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Eur J Hum Genet 14:1125-9. 2006
    ..Since also post-methionine load tHcy concentrations are found to be associated with an increased risk for cardiovascular disease (CVD), this 31 bp VNTR may be considered a risk factor for CVD...
  12. ncbi request reprint Enhanced cellular adenosine uptake limits adenosine receptor stimulation in patients with hyperhomocysteinemia
    Niels P Riksen
    Department of Pharmacology Toxicology 233, University Medical Centre Nijmegen, Geert Grooteplein 21, 6525 EZ Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    Arterioscler Thromb Vasc Biol 25:109-14. 2005
    ..We tested this hypothesis in patients with classical homocystinuria (n=9, plasma homocysteine 93.1+/-24.7 micromol/L) and matched controls (n=8, homocysteine 9.1+/-1.0)...
  13. ncbi request reprint DNA methylation status is not impaired in treated cystathionine beta-synthase (CBS) deficient patients
    Sandra G Heil
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands
    Mol Genet Metab 91:55-60. 2007
    ..In this study we aimed to investigate whether DNA methylation is disturbed in patients with hyperhomocysteinemia due to CBS-deficiency...
  14. ncbi request reprint Reduced adenosine receptor stimulation as a pathogenic factor in hyperhomocysteinemia
    Niels P Riksen
    Department of Pharmacology Toxicology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Clin Chem Lab Med 43:1001-6. 2005
    ..These observations provide us with additional pharmacological targets, such as adenosine uptake inhibition, to reduce cardiovascular risk in patients with hyperhomocysteinemia...
  15. ncbi request reprint Variation and expression of dihydrofolate reductase (DHFR) in relation to spina bifida
    Ivon J M van der Linden
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    Mol Genet Metab 91:98-103. 2007
    ..73, p=0.09). We did not find evidence for an effect of the DHFR 19-bp deletion or 9-bp repeat on spina bifida risk in mothers and children. An effect of the 6/6 repeat genotype on DHFR expression cannot be ruled out...
  16. pmc The 894G>T variant in the endothelial nitric oxide synthase gene and spina bifida risk
    Ivon J M van der Linden
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    J Hum Genet 52:516-20. 2007
    ..55-13.22 and OR 3.38, 95%CI 1.46-7.84, respectively). In our study population, the NOS3 894GT/TT genotype might be a risk factor for having a spina bifida affected child in mothers who already have an impaired homocysteine metabolism...
  17. ncbi request reprint No added value of the methionine loading task in assessment for venous thrombosis and cardiovascular disease risk
    Miranda B A Keijzer
    Dept of Endocrinology, Radboud University Nijmegen Medical Centre, Geert Grooteplein 8, 6525 GA Nijmegen, The Netherlands
    Thromb Haemost 95:380-5. 2006
    ..The methionine loading test has no added value next to measuring fasting homocysteine levels for identifying subjects at risk for venous thrombosis or cardiovascular disease and for that reason should not be used in clinical practice...
  18. doi request reprint An association study of 45 folate-related genes in spina bifida: Involvement of cubilin (CUBN) and tRNA aspartic acid methyltransferase 1 (TRDMT1)
    Barbara Franke
    Department of Human Genetics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Birth Defects Res A Clin Mol Teratol 85:216-26. 2009
    ..5 to 12 per 1000 births globally. In this article we attempt to identify genes related to folate and its metabolic pathways that are involved in the etiology of spina bifida...
  19. ncbi request reprint Associations of common polymorphisms in the thymidylate synthase, reduced folate carrier and 5-aminoimidazole-4-carboxamide ribonucleotide transformylase/inosine monophosphate cyclohydrolase genes with folate and homocysteine levels and venous thrombosis
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    Clin Chem Lab Med 45:471-6. 2007
    ..Genetic variation in folate-metabolizing genes may affect folate availability and hence confer a greater risk of venous thrombosis...
  20. ncbi request reprint Genetics of hyperhomocysteinaemia in cardiovascular disease
    Karin J A Lievers
    Laboratory of Paediatrics and Neurology, University Medical Centre Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    Ann Clin Biochem 40:46-59. 2003
    ..We report on both environmental and genetic determinants of hyperhomocysteinaemia and give a detailed overview of all the genetic determinants that have been reported to date...
  21. ncbi request reprint Molecular genetic analysis of the human dihydrofolate reductase gene: relation with plasma total homocysteine, serum and red blood cell folate levels
    Henkjan Gellekink
    Laboratory of Paediatrics and Neurology, Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Eur J Hum Genet 15:103-9. 2007
    ..The 19-bp del/del genotype was associated with a lower plasma tHcy (-14.4% [95% confidence interval: -23.5 to -4.5], P=0.006) compared with the wild-type genotype. This may suggest that intracellular folate levels are affected...
  22. ncbi request reprint Genetic variation in genes of folate metabolism and neural-tube defect risk
    Ivon J M van der Linden
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    Proc Nutr Soc 65:204-15. 2006
    ..In the present review relevant SNP in genes that code for enzymes involved in folate transport and uptake, the folate cycles and homocysteine metabolism are summarised and the importance of these SNP discussed in relation to NTD risk...
  23. ncbi request reprint The effect of homocysteine reduction by B-vitamin supplementation on inflammatory markers
    Anita C T M Peeters
    Department of Endocrinology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Clin Chem Lab Med 45:54-8. 2007
    ....
  24. ncbi request reprint Maternal MTHFR 677C>T is a risk factor for congenital heart defects: effect modification by periconceptional folate supplementation
    Ingrid M van Beynum
    Children s Heart Centre, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands
    Eur Heart J 27:981-7. 2006
    ..We studied the association between MTHFR 677C > T variants and CHD risk. The interaction with periconceptional folate supplementation was also investigated...
  25. doi request reprint Protective effect of periconceptional folic acid supplements on the risk of congenital heart defects: a registry-based case-control study in the northern Netherlands
    Ingrid M van Beynum
    Children s Heart Centre, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
    Eur Heart J 31:464-71. 2010
    ..To investigate the potentially protective of periconceptional folic acid use on the risk of congenital heart defects (CHDs) relative to other non-folate related malformations...
  26. ncbi request reprint The H475Y polymorphism in the glutamate carboxypeptidase II gene increases plasma folate without affecting the risk for neural tube defects in humans
    Lydia A Afman
    University Medical Center Nijmegen, Department of Pediatrics, Laboratory of Pediatrics and Neurology, The Netherlands
    J Nutr 133:75-7. 2003
    ....
  27. ncbi request reprint Role for mitochondrial uncoupling protein-2 (UCP2) in hyperhomocysteinemia and venous thrombosis risk?
    Sandra G Heil
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    Clin Chem Lab Med 46:655-9. 2008
    ....
  28. ncbi request reprint Effect of genetic variation in the human S-adenosylhomocysteine hydrolase gene on total homocysteine concentrations and risk of recurrent venous thrombosis
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology, University Medical Center Nijmegen, The Netherlands
    Eur J Hum Genet 12:942-8. 2004
    ..27 (95% CI 0.55-2.94), whereas the -34CT genotype confers a risk of 1.25 (95% CI 0.44-3.52) compared with the wild-type genotype at this locus. However, the wide confidence intervals do not allow firm conclusions to be drawn...
  29. ncbi request reprint Single nucleotide polymorphisms in the transcobalamin gene: relationship with transcobalamin concentrations and risk for neural tube defects
    Lydia A Afman
    University Medical Center Nijmegen, Department of Pediatrics, Laboratory of Pediatrics and Neurology, P O Box 9101, 6500 HB Nijmegen, The Netherlands
    Eur J Hum Genet 10:433-8. 2002
    ....
  30. pmc S-adenosylmethionine and S-adenosylhomocysteine levels in the aging brain of APP/PS1 Alzheimer mice
    Carlijn R Hooijmans
    Department of Anatomy and Department of Cognitive Neuroscience, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, 6500 HB, Nijmegen, The Netherlands
    Neurol Sci 30:439-45. 2009
    ..No effect of the omega-3 fatty acid docosahexaenoic acid (DHA) or cholesterol-enriched diets on AdoMet or AdoHcy levels were found...
  31. ncbi request reprint A simple high-throughput method for the determination of plasma methylmalonic acid by liquid chromatography-tandem mass spectrometry
    Henk J Blom
    Laboratory of Pediatrics and Neurology, University Medical Center St Radboud, Nijmegen, The Netherlands
    Clin Chem Lab Med 45:645-50. 2007
    ..Methylmalonic acid (MMA) is the most sensitive and specific marker of intracellular Cbl status, but its application is hindered by limited methods available for accurate and high-throughput MMA determination...
  32. ncbi request reprint Potential role for adenosine in the pathogenesis of the vascular complications of hyperhomocysteinemia
    Niels P Riksen
    Department of Pharmacology Toxicology, University Medical Centre Nijmegen, P O Box 9101, 6500 HB Nijmegen, The Netherlands
    Cardiovasc Res 59:271-6. 2003
    ..In this respect, a decrease in the adenosine concentration could contribute significantly to the cardiovascular effects of hyperhomocysteinemia...
  33. ncbi request reprint Total homocysteine and its predictors in Dutch children
    Ingrid M van Beynum
    Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands
    Am J Clin Nutr 81:1110-6. 2005
    ..Limited data are available about the influence of these factors on tHcy in children...
  34. ncbi request reprint Improved cardiovascular risk profile and renal function in renal transplant patients after randomized conversion from cyclosporine to tacrolimus
    Marika A Artz
    Department of Nephrology, University Medical Center of Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands
    J Am Soc Nephrol 14:1880-8. 2003
    ..In conclusion, conversion from cyclosporine to tacrolimus in stable renal transplant patients has a beneficial effect on renal function, BP, serum concentration and atherogenic properties of serum lipids, and fibrinogen...
  35. doi request reprint Common 894G>T single nucleotide polymorphism in the gene coding for endothelial nitric oxide synthase (eNOS) and risk of congenital heart defects
    Ingrid M van Beynum
    Children s Heart Center, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    Clin Chem Lab Med 46:1369-75. 2008
    ..eNOS-deficient mice have impaired cardiac development resulting in congenital heart defects (CHDs). In humans, a single nucleotide polymorphism in the gene coding for eNOS (894G>T) is associated with birth defects...
  36. ncbi request reprint Decreased intracellular ATP content and intact mitochondrial energy generating capacity in human cystinotic fibroblasts
    Elena N Levtchenko
    Department of Pediatrics, Radboud University Nijmegen Medical Center, The Netherlands
    Pediatr Res 59:287-92. 2006
    ....
  37. ncbi request reprint Thioredoxin interacting protein in Dutch families with familial combined hyperlipidemia
    Gerly M van der Vleuten
    Department of Medicine, Division of General Internal Medicine, University Medical Center Nijmegen, Nijmegen, The Netherlands
    Am J Med Genet A 130:73-5. 2004
    ..This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299/suppmat/index.html...
  38. ncbi request reprint Strict cysteamine dose regimen is required to prevent nocturnal cystine accumulation in cystinosis
    Elena N Levtchenko
    Department of Paediatric Nephrology, Radboud University Nijmegen Medical Centre, P O 9101, 6500 HB, Nijmegen, The Netherlands
    Pediatr Nephrol 21:110-3. 2006
    ..We provide evidence that cysteamine has to be administered every 6 h, including the night, as it has much better effect for maintaining low PMN cystine levels...
  39. doi request reprint N-acetyl resonances in in vivo and in vitro NMR spectroscopy of cystic ovarian tumors
    Eva Kolwijck
    Department of Obstetrics and Gynecology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    NMR Biomed 22:1093-9. 2009
    ..0-2.1 ppm resonance complex in ovarian cyst fluid. This spectral region seems to contain resonances from biomarkers that provide relevant clinical information on the type of ovarian tumor...
  40. ncbi request reprint Cystine dimethylester model of cystinosis: still reliable?
    Martijn J Wilmer
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, 6500 HB, Nijmegen, The Netherlands
    Pediatr Res 62:151-5. 2007
    ..These effects are not observed in cystinotic cells, indicating that a more appropriate model is required for studying the pathogenesis of cystinosis...
  41. ncbi request reprint Stable-isotope dilution liquid chromatography-electrospray injection tandem mass spectrometry method for fast, selective measurement of S-adenosylmethionine and S-adenosylhomocysteine in plasma
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
    Clin Chem 51:1487-92. 2005
    ..We aimed to develop a rapid and sensitive method to measure AdoHcy and its precursor S-adenosylmethionine (AdoMet)...
  42. ncbi request reprint Homocysteine determinants and the evidence to what extent homocysteine determines the risk of coronary heart disease
    Angelika de Bree
    Laboratory of Pediatrics and Neurology, University Medical Center, Nijmegen, The Netherlands
    Pharmacol Rev 54:599-618. 2002
    ..Ongoing intervention trials will indicate whether homocysteine-lowering through vitamin supplementation, prevents CHD in the treatment groups...
  43. ncbi request reprint Cytochrome P450-2C11 mRNA is not expressed in endothelial cells dissected from rat renal arterioles
    Sandra G Heil
    Laboratory of Pediatrics and Neurology, University Medical Center Nijmegen, Nijmegen, The Netherlands
    Nephron Physiol 99:p43-9. 2005
    ..We hypothesized that if CYP2C11 is involved in the EDHF-mediated responses, its mRNA should be expressed in endothelial cells. We, therefore, examined the mRNA expression of CYP2C11 in endothelial cells of renal arterioles...
  44. ncbi request reprint Elevated oxidized glutathione in cystinotic proximal tubular epithelial cells
    Martijn J G Wilmer
    Laboratory of Pediatrics and Neurology, Radboud University Nijmegen Medical Centre, The Netherlands
    Biochem Biophys Res Commun 337:610-4. 2005
    ..In conclusion, elevated oxidized glutathione in cystinotic proximal tubular epithelial cell lines suggests increased oxidative stress, which may contribute to tubular dysfunction in cystinosis...
  45. ncbi request reprint Interaction between hyperhomocysteinemia, mutated methylenetetrahydrofolatereductase (MTHFR) and inherited thrombophilic factors in recurrent venous thrombosis
    Miranda B A J Keijzer
    Department of Endocrinology, University Medical Center Nijmegen, 6500 HB Nijmegen, The Netherlands
    Thromb Haemost 88:723-8. 2002
    ..7 (95% CI: 3.3 to 108). We conclude that hyperhomocysteinemia and factor V Leiden are risk factors for recurrent venous thrombosis. The risk of thrombosis appeared high for individuals who had both risk factors...
  46. ncbi request reprint Polymorphisms in the transcobalamin gene: association with plasma homocysteine in healthy individuals and vascular disease patients
    Karin J A Lievers
    Departments of Pediatrics, Division of Endocrinology, University Medical Center Nijmegen, 6500 HB Nijmegen, The Netherlands
    Clin Chem 48:1383-9. 2002
    ....
  47. doi request reprint Prospective study of homocysteine and MTHFR 677TT genotype and risk for venous thrombosis in a general population--results from the HUNT 2 study
    Inger Anne Naess
    Department of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology NTNU, Trondheim, Norway
    Br J Haematol 141:529-35. 2008
    ..The MTHFR 677TT genotype was not related to risk for VT. In conclusion, elevated homocysteine levels in the general population predicted subsequent first VT in men but not in women...
  48. ncbi request reprint The association of betaine, homocysteine and related metabolites with cognitive function in Dutch elderly people
    Simone J P M Eussen
    Division of Human Nutrition, Wageningen University, P O Box 8129 6700 EV Wageningen, The Netherlands
    Br J Nutr 98:960-8. 2007
    ..There was a tendency of participants with the largest increases in betaine concentrations to show the greatest improvement in memory function...
  49. ncbi request reprint Why are homocysteine levels increased in kidney failure? A metabolic approach
    Henk J Blom
    Department of Pediatrics, University Hospital Nijmegen, The Netherlands
    J Lab Clin Med 139:262-8. 2002
  50. doi request reprint Sedoheptulokinase deficiency due to a 57-kb deletion in cystinosis patients causes urinary accumulation of sedoheptulose: elucidation of the CARKL gene
    Mirjam M C Wamelink
    Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands
    Hum Mutat 29:532-6. 2008
    ....
  51. ncbi request reprint No evidence for a preferential transmission of the methylenetetrahydrofolate reductase 677T allele in families with schizophrenia offspring
    Jan Willem Muntjewerff
    GGz Nijmegen, Mental Health Institute, 6503 GM Nijmegen, The Netherlands
    Am J Med Genet B Neuropsychiatr Genet 144:891-4. 2007
    ..In addition, we found no evidence that the maternal genotype influences the risk of having schizophrenia offspring substantially...
  52. ncbi request reprint Polymorphisms in catechol-O-methyltransferase and methylenetetrahydrofolate reductase in relation to the risk of schizophrenia
    Jan Willem Muntjewerff
    GGz Nijmegen, Mental Health Institute, PO Box 7049, 6503 GM Nijmegen, The Netherlands
    Eur Neuropsychopharmacol 18:99-106. 2008
    ..Evidence is emerging for the association of aberrant homocysteine-methylation cycle and increased risk of schizophrenia...
  53. ncbi request reprint The methionine synthase reductase 66A>G polymorphism is a maternal risk factor for spina bifida
    Ivon J M van der Linden
    Laboratory of Pediatrics and Neurology 830, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    J Mol Med (Berl) 84:1047-54. 2006
    ..96, 95% CI 0.46-2.01). These data show that the MTRR 66GG genotype is a maternal risk factor for spina bifida especially when intracellular vitamin B12 status is low...
  54. ncbi request reprint Endothelium-derived hyperpolarizing factor-mediated renal vasodilatory response is impaired during acute and chronic hyperhomocysteinemia
    An S De Vriese
    Renal Unit, University Hospital, Gent, Belgium
    Circulation 109:2331-6. 2004
    ..The influence of hyperhomocysteinemia on EDHF is unknown. The present in vivo study evaluates the integrity of the EDHF pathway in the renal microcirculation of rats with acute and chronic hyperhomocysteinemia...
  55. ncbi request reprint Vitamin and homocysteine status of mothers and infants and the risk of nonsyndromic orofacial clefts
    Iris A L M van Rooij
    Department of Epidemiology and Biostatistics, University Medical Center Nijmegen, The Netherlands
    Am J Obstet Gynecol 189:1155-60. 2003
    ..This study was undertaken to investigate the involvement of maternal and infant B vitamins and homocysteine as risk factors for orofacial clefting...
  56. ncbi request reprint The 2756A>G variant in the gene encoding methionine synthase: its relation with plasma homocysteine levels and risk of coronary heart disease in a Dutch case-control study
    Mariska Klerk
    Division of Human Nutrition and Epidemiology, Wageningen University, Wageningen, The Netherlands
    Thromb Res 110:87-91. 2003
    ..A 2756A>G polymorphism has been found in the gene (MTR) coding for methionine synthase, an enzyme catalyzing remethylation of homocysteine to methionine...
  57. ncbi request reprint Effect of the methylenetetrahydrofolate reductase 677C-->T mutation on the relations among folate intake and plasma folate and homocysteine concentrations in a general population sample
    Angelika de Bree
    Department of Chronic Disease Epidemiology, National Institute of Public Health and the Environment, Bilthoven, Netherlands
    Am J Clin Nutr 77:687-93. 2003
    ..Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate and homocysteine metabolism. The common MTHFR 677C-->T polymorphism decreases the enzyme's activity...
  58. ncbi request reprint Coronary heart disease mortality, plasma homocysteine, and B-vitamins: a prospective study
    Angelika de Bree
    Department of Chronic Disease Epidemiology pb 101, National Institute of Public Health and the Environment RIVM, PO Box 1, NL 3720 BA Bilthoven, The Netherlands
    Atherosclerosis 166:369-77. 2003
    ..Higher folate concentrations may be protective of CHD, but this needs confirmation...
  59. ncbi request reprint MTHFR 677C-->T polymorphism and risk of coronary heart disease: a meta-analysis
    Mariska Klerk
    Division of Human Nutrition and Epidemiology, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
    JAMA 288:2023-31. 2002
    ..The MTHFR 677C-->T polymorphism is a genetic alteration in an enzyme involved in folate metabolism that causes elevated homocysteine concentrations, but its relevance to risk of CHD is uncertain...
  60. ncbi request reprint Influence of a glutamate carboxypeptidase II (GCPII) polymorphism (1561C-->T) on plasma homocysteine, folate and vitamin B(12) levels and its relationship to cardiovascular disease risk
    Karin J A Lievers
    Department of Pediatrics, PO Box 9101, University Medical Center Nijmegen, 6500 HB, Nijmegen, The Netherlands
    Atherosclerosis 164:269-73. 2002
    ....
  61. ncbi request reprint Coronary endothelial function in hyperhomocysteinemia: improvement after treatment with folic acid and cobalamin in patients with coronary artery disease
    Frank F Willems
    Department of Cardiology, Rijnstate Hospital, Arnhem, The Netherlands
    J Am Coll Cardiol 40:766-72. 2002
    ..We evaluated the effect of therapy with folic acid and cobalamin on coronary endothelial function, expressed as a change in volumetric coronary blood flow (CBF), in hyperhomocysteinemic patients with coronary artery disease (CAD)...
  62. ncbi request reprint Bioavailability of polyglutamyl folic acid relative to that of monoglutamyl folic acid in subjects with different genotypes of the glutamate carboxypeptidase II gene
    Alida Melse-Boonstra
    Wageningen Centre for Food Sciences and the Division of Human Nutrition, Wageningen University, 6700 EV Wageningen, Netherlands
    Am J Clin Nutr 80:700-4. 2004
    ..The 1561T allele of the glutamate carboxypeptidase II gene (GCPII), which codes for folylpoly-gamma-glutamyl carboxypeptidase, may impair intestinal absorption of dietary folates...
  63. ncbi request reprint The effect of homocysteine reduction by B-vitamin supplementation on markers of endothelial dysfunction
    Anita C T M Peeters
    Department of Endocrinology, University Medical Centre Nijmegen, The Netherlands
    Thromb Haemost 92:1086-91. 2004
    ..In conclusion, the results of our study show that homocysteine reduction by B-vitamin supplementation has no effect on markers of endothelial dysfunction in healthy volunteers...
  64. ncbi request reprint Hyperhomocysteinemia, methylenetetrahydrofolate reductase 677TT genotype, and the risk for schizophrenia: a Dutch population based case-control study
    Jan Willem Muntjewerff
    GGz Nijmegen, Mental Health Institute, Nijmegen, The Netherlands
    Am J Med Genet B Neuropsychiatr Genet 135:69-72. 2005
    ..91-1.8]. Elevated homocysteine levels and the MTHFR 677TT genotype are associated with an increased risk for schizophrenia. These observations support a causal relation between disturbed homocysteine metabolism and schizophrenia...
  65. ncbi request reprint Effect of oral vitamin B-12 with or without folic acid on cognitive function in older people with mild vitamin B-12 deficiency: a randomized, placebo-controlled trial
    Simone J Eussen
    Division of Human Nutrition, Wageningen University, Wageningen, Netherlands
    Am J Clin Nutr 84:361-70. 2006
    ..Vitamin B-12 deficiency is associated with cognitive impairment in older people. However, evidence from randomized trials of the effects of vitamin B-12 supplementation on cognitive function is limited and inconclusive...
  66. ncbi request reprint Can we exclude the TXNIP gene as a candidate gene for familial combined hyperlipidemia?
    Gerly M van der Vleuten
    Am J Med Genet A 140:1010-2. 2006
  67. ncbi request reprint Migraine and MTHFR C677T genotype in a population-based sample
    Ann I Scher
    Department of Preventive Medicine and Biometrics, Uniformed Services University, Bethesda, MD 20814 4799, USA
    Ann Neurol 59:372-5. 2006
    ..We assessed the association of the MTHFR C677T variant with migraine and the mediating effect of cardiovascular risk factors and metabolic markers of genotype status...
  68. ncbi request reprint Effect of supplementation with cobalamin carried either by a milk product or a capsule in mildly cobalamin-deficient elderly Dutch persons
    Rosalie A M Dhonukshe-Rutten
    Department of Human Nutrition, Wageningen University, Wageningen, The Netherlands
    Am J Clin Nutr 82:568-74. 2005
    ..A high prevalence of cobalamin deficiency occurs in the elderly population, which may be treated orally or with injections. Little is known about the relative bioavailability of crystalline cobalamin added to food products...
  69. ncbi request reprint Genetic determinants of plasma total homocysteine
    Henkjan Gellekink
    Laboratory of Pediatrics and Neurology 424, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
    Semin Vasc Med 5:98-109. 2005
    ..In the last section, we summarize the polymorphisms, for which the obtained data provides evidence for their involvement in Hhcy at the population level, and discuss how to continue our search for genetic determinants of tHcy...
  70. ncbi request reprint Inhibition of transmethylation disturbs neurulation in chick embryos
    Lydia A Afman
    Department of Anatomy and Embryology, Maastricht University, P O Box 616, 6200 MD, The Netherlands
    Brain Res Dev Brain Res 158:59-65. 2005
    ..This study, therefore, indicates that the Hcy-induced delay of the neural tube closure is caused by the inhibition of transmethylation via elevation of AdoHcy levels and a reduction of the AdoMet/AdoHcy ratio...
  71. ncbi request reprint Betaine and folate status as cooperative determinants of plasma homocysteine in humans
    Pal I Holm
    LOCUS for Homocysteine and Related Vitamins, University of Bergen, Norway
    Arterioscler Thromb Vasc Biol 25:379-85. 2005
    ..Two published studies have demonstrated that betaine in the circulation is a determinant of plasma total homocysteine, but none had sufficient power to investigate the possible effect modification by folate status...
  72. ncbi request reprint Effect of homocysteine reduction by B-vitamin supplementation on markers of clotting activation
    Mariska Klerk
    Division of Human Nutrition and Epidemiology, Wageningen University, Wageningen Centre for Food Sciences, Wageningen
    Thromb Haemost 88:230-5. 2002
    ..A 10.4% reduction was observed for D-dimer (p = 0.08). In conclusion, it appears that in healthy subjects homocysteine reduction by B-vitamin supplementation has a modest beneficial effect on clotting activation...