K de Meer

Summary

Publications

  1. ncbi request reprint [6S]5-methyltetrahydrofolate or folic acid supplementation and absorption and initial elimination of folate in young and middle-aged adults
    K de Meer
    Department of Clinical Chemistry, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
    Eur J Clin Nutr 59:1409-16. 2005
  2. ncbi request reprint [Karl Landsteiner (1868-1943) and the specificity of serological reactions, one hundred years ago and now]
    K de Meer
    VU Medisch Centrum, afd Kindergeneeskunde, Postbus 7075, 1007 MB Amsterdam
    Ned Tijdschr Geneeskd 146:575-9. 2002
  3. ncbi request reprint Oral estradiol decreases plasma homocysteine, vitamin B6, and albumin in postmenopausal women but does not change the whole-body homocysteine remethylation and transmethylation flux
    R G V Smolders
    Project Aging Women, Vrije Universiteit University Medical Center, Department of Obstetrics and Gynecology, P O Box 7057, 1007 MB Amsterdam, The Netherlands
    J Clin Endocrinol Metab 90:2218-24. 2005
  4. ncbi request reprint Homocysteine and methionine metabolism in ESRD: A stable isotope study
    C van Guldener
    Department of Internal Medicine, Vrije Universiteit, Amsterdam, The Netherlands
    Kidney Int 56:1064-71. 1999
  5. ncbi request reprint Determination of isotopic enrichments of [1-13C]homocysteine, [1-13C]methionine and [2H3-methyl-1-13C]methionine in human plasma by gas chromatography-negative chemical ionization mass spectrometry
    W Kulik
    Department of Clinical Chemistry, University Hospital Vrije Universiteit, Amsterdam, The Netherlands
    J Chromatogr B Biomed Sci Appl 738:99-105. 2000
  6. ncbi request reprint 5-Methyltetrahydrofolic acid and folic acid measured in plasma with liquid chromatography tandem mass spectrometry: applications to folate absorption and metabolism
    R M Kok
    Department of Clinical Chemistry, VU University Medical Center, 1007 MB Amsterdam, The Netherlands
    Anal Biochem 326:129-38. 2004
  7. ncbi request reprint No net renal extraction of homocysteine in fasting humans
    C van Guldener
    Department of Nephrology, Vrije Universiteit, Amsterdam, The Netherlands
    Kidney Int 54:166-9. 1998
  8. ncbi request reprint Hormone replacement influences homocysteine levels in the methionine-loading test: a randomized placebo controlled trial in postmenopausal women
    R G V Smolders
    Project Aging Women, Department of Obstetrics and Gynaecology, Institute for Cardiovascular Research Vrije Universiteit, VU University Medical Center, PO Box 7057, Amsterdam 1007 MB, The Netherlands
    Eur J Obstet Gynecol Reprod Biol 117:55-9. 2004
  9. ncbi request reprint Determination of extracellular and intracellular enrichments of [1-(13)C]-alpha-ketoisovalerate using enzymatically converted [1-(13)C]-valine standardization curves and gas chromatography-mass spectrometry
    W Kulik
    Department of Clinical Chemistry, University Hospital Vrije Universiteit, Amsterdam, The Netherlands
    J Chromatogr B Biomed Sci Appl 729:211-6. 1999
  10. ncbi request reprint S-adenosylhomocysteine and the ratio of S-adenosylmethionine to S-adenosylhomocysteine are not related to folate, cobalamin and vitamin B6 concentrations
    A Becker
    Department of Internal Medicine, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
    Eur J Clin Invest 33:17-25. 2003

Collaborators

Detail Information

Publications11

  1. ncbi request reprint [6S]5-methyltetrahydrofolate or folic acid supplementation and absorption and initial elimination of folate in young and middle-aged adults
    K de Meer
    Department of Clinical Chemistry, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
    Eur J Clin Nutr 59:1409-16. 2005
    ..To assess the effects of supplementation with the diastereoisomer of 5-methyltetrahydrofolate ([6S]5-methylTHF), as an alternative supplement for folic acid, on folate absorption and elimination, in two age groups...
  2. ncbi request reprint [Karl Landsteiner (1868-1943) and the specificity of serological reactions, one hundred years ago and now]
    K de Meer
    VU Medisch Centrum, afd Kindergeneeskunde, Postbus 7075, 1007 MB Amsterdam
    Ned Tijdschr Geneeskd 146:575-9. 2002
    ..Nowadays, his work is celebrated for its numerous excellent contributions to the fields of transfusion and transplantation medicine, population genetics, immunology, and infectiology...
  3. ncbi request reprint Oral estradiol decreases plasma homocysteine, vitamin B6, and albumin in postmenopausal women but does not change the whole-body homocysteine remethylation and transmethylation flux
    R G V Smolders
    Project Aging Women, Vrije Universiteit University Medical Center, Department of Obstetrics and Gynecology, P O Box 7057, 1007 MB Amsterdam, The Netherlands
    J Clin Endocrinol Metab 90:2218-24. 2005
    ....
  4. ncbi request reprint Homocysteine and methionine metabolism in ESRD: A stable isotope study
    C van Guldener
    Department of Internal Medicine, Vrije Universiteit, Amsterdam, The Netherlands
    Kidney Int 56:1064-71. 1999
    ..The cause of hyperhomocysteinemia in renal failure is unknown, and therapies have not been able to normalize plasma homocysteine levels. Insight into methionine-homocysteine metabolism in ESRD is therefore necessary...
  5. ncbi request reprint Determination of isotopic enrichments of [1-13C]homocysteine, [1-13C]methionine and [2H3-methyl-1-13C]methionine in human plasma by gas chromatography-negative chemical ionization mass spectrometry
    W Kulik
    Department of Clinical Chemistry, University Hospital Vrije Universiteit, Amsterdam, The Netherlands
    J Chromatogr B Biomed Sci Appl 738:99-105. 2000
    ..The method was applied in a [2H3-methyl-1-13C]methionine tracer infusion study in a biological model...
  6. ncbi request reprint 5-Methyltetrahydrofolic acid and folic acid measured in plasma with liquid chromatography tandem mass spectrometry: applications to folate absorption and metabolism
    R M Kok
    Department of Clinical Chemistry, VU University Medical Center, 1007 MB Amsterdam, The Netherlands
    Anal Biochem 326:129-38. 2004
    ..We conclude that LC-MS-MS offers increased sensitivity for quantification of plasma concentrations and enrichments of 5-methylTHF and folic acid and is applicable to stable-isotope studies in humans...
  7. ncbi request reprint No net renal extraction of homocysteine in fasting humans
    C van Guldener
    Department of Nephrology, Vrije Universiteit, Amsterdam, The Netherlands
    Kidney Int 54:166-9. 1998
    ..We studied homocysteine extraction in the normal human kidney...
  8. ncbi request reprint Hormone replacement influences homocysteine levels in the methionine-loading test: a randomized placebo controlled trial in postmenopausal women
    R G V Smolders
    Project Aging Women, Department of Obstetrics and Gynaecology, Institute for Cardiovascular Research Vrije Universiteit, VU University Medical Center, PO Box 7057, Amsterdam 1007 MB, The Netherlands
    Eur J Obstet Gynecol Reprod Biol 117:55-9. 2004
    ..To investigate the mechanism by which exogenous oestrogen influences the homocysteine metabolism in postmenopausal women...
  9. ncbi request reprint Determination of extracellular and intracellular enrichments of [1-(13)C]-alpha-ketoisovalerate using enzymatically converted [1-(13)C]-valine standardization curves and gas chromatography-mass spectrometry
    W Kulik
    Department of Clinical Chemistry, University Hospital Vrije Universiteit, Amsterdam, The Netherlands
    J Chromatogr B Biomed Sci Appl 729:211-6. 1999
    ..1-(13)C]-KIV enrichment could be determined+/-0.1 MPE (C.V. 1%), and extracellular [1-(13)C]-KIV enrichment was a reliable estimate of intracellular (skeletal muscle, bone growth plate) [1-(13)C]-KIV enrichment...
  10. ncbi request reprint S-adenosylhomocysteine and the ratio of S-adenosylmethionine to S-adenosylhomocysteine are not related to folate, cobalamin and vitamin B6 concentrations
    A Becker
    Department of Internal Medicine, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
    Eur J Clin Invest 33:17-25. 2003
    ..Therefore, it is relevant to know how these moieties are interrelated, and whether, as is the case for homocysteine, they are influenced by blood levels of folate, cobalamin or vitamin B6...
  11. ncbi request reprint Determination of 13C and 15N enrichments of urea in plasma by gas chromatography-combustion isotope ratio mass spectrometry and gas chromatography-mass spectrometry using the 2-methoxypyrimidine derivative
    W Kulik
    VU University Medical Center, Department of Clinical Chemistry, Metabolic Laboratory, Amsterdam, The Netherlands
    J Chromatogr B Analyt Technol Biomed Life Sci 791:399-405. 2003
    ..15% MPE (95% confidence interval). Application of the method in a combined 13C-urea bolus and 15N(2)-urea primed constant infusion experiment in piglet was demonstrated...