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2. Clinical presentation and long-term follow-up of dopamine beta hydroxylase deficiency

Author

Wassenberg, Tessa, Deinum, Jaap, van Ittersum, Frans J., Kamsteeg, Erik Jan, Pennings, Maartje, Verbeek, Marcel M., Wevers, Ron A., van Albada, Mirjam E., Kema, Ido P., Versmissen, Jorie, van den Meiracker, Ton, Lenders, Jacques W.M., Monnens, Leo, Willemsen, Michèl A., Wassenberg, Tessa, Deinum, Jaap, van Ittersum, Frans J., Kamsteeg, Erik Jan, Pennings, Maartje, Verbeek, Marcel M., Wevers, Ron A., van Albada, Mirjam E., Kema, Ido P., Versmissen, Jorie, van den Meiracker, Ton, Lenders, Jacques W.M., Monnens, Leo, and Willemsen, Michèl A.

Abstract

Dopamine beta hydroxylase (DBH) deficiency is an extremely rare autosomal recessive disorder with severe orthostatic hypotension, that can be treated with L-threo-3,4-dihydroxyphenylserine (L-DOPS). We aimed to summarize clinical, biochemical, and genetic data of all world-wide reported patients with DBH-deficiency, and to present detailed new data on long-term follow-up of a relatively large Dutch cohort. We retrospectively describe 10 patients from a Dutch cohort and 15 additional patients from the literature. We identified 25 patients (15 females) from 20 families. Ten patients were diagnosed in the Netherlands. Duration of follow-up of Dutch patients ranged from 1 to 21 years (median 13 years). All patients had severe orthostatic hypotension. Severely decreased or absent (nor)epinephrine, and increased dopamine plasma concentrations were found in 24/25 patients. Impaired kidney function and anemia were present in all Dutch patients, hypomagnesaemia in 5 out of 10. Clinically, all patients responded very well to L-DOPS, with marked reduction of orthostatic complaints. However, orthostatic hypotension remained present, and kidney function, anemia, and hypomagnesaemia only partially improved. Plasma norepinephrine increased and became detectable, while epinephrine remained undetectable in most patients. We confirm the core clinical characteristics of DBH-deficiency and the pathognomonic profile of catecholamines in body fluids. Impaired renal function, anemia, and hypomagnesaemia can be part of the clinical presentation. The subjective response to L-DOPS treatment is excellent and sustained, although the neurotransmitter profile in plasma does not normalize completely. Furthermore, orthostatic hypotension as well as renal function, anemia, and hypomagnesaemia improve only partially.

Published
2021

7. Hereditary isolate renal magnesium loss maps to chromosome 11q23

Author

Meij, Iwan C., Saar, Kathrin, Heuvel, Lambert P.W.J. van den, Nuernberg, Gudrun, Vollmer, Martin, Hindebrandt, Friedhelm, Reis, Andre, Monnens, Leo A.H., and Knoers, Nine V.A.M.

Subjects
Chromosome mapping -- Usage, Genetic disorders -- Research, Magnesium in the body -- Genetic aspects, Kidneys -- Abnormalities, Biological sciences
Abstract

Hypomagnesemia resulting from isolated renal magnesium loss has been seen in two apparently unrelated Dutch families with autosomal dominant inheritance. A possible candidate region on chromosome 9q was excluded in a genomewide linkage study. It took in the gene for intestinal hypomagnesemia with secondary hypoglycemia. Linkage to markers on chromosome 11q23 was found. A common haplotype segregating in the families was identified. That suggested existence of a common ancestor and of one hypomagnesemia-causing mutation in the families. The 11q23 region takes in a gene different from the one involved in intestinal magnesium handling that is related to renal magnesium handling and mutated in the patients studied.

Published
1999

21. Requirement of human renal water channel aquaporin-2 for vasopressin-dependent concentration of urine

Author

Deen, Peter M.T., Verdijk, Marian A.J., Knoers, Nine V.A.M., Wieringa, Be, Monnens, Leo A.H., van Os, Carel H., and van Oost, Bernard A.

Subjects
Vasopressin -- Research, Urine -- Research, Science and technology, Research
Abstract

Concentration of urine in mammals is regulated by the antidiuretic hormone vasopressin. Binding of vasopressin to its V2 receptor leads to the insertion of water channels in apical membranes of principal cells in collecting ducts. In nephrogenic diabetes insipidus (NDI), the kidney fails to concentrate urine in response to vasopressin. A male patient with an autosomal recessive form of NDI was found to be a compound heterozygote for two mutations in the gene encoding aquaporin-2, a water channel. Functional expression studies in Xenopus oocytes revealed that each mutation resulted in nonfunctional water channel proteins. Thus, aquaporin-2 is essential for vasopressin-dependent concentration of urine., The cloning of water-selective channels has begun to reveal the molecular basis of renal water transport. The water-selective channel, aquaporin-1 or CHIP28, is responsible for the constitutively high water permeability [...]

Published
1994

31. The Effect of Shiga Toxin on Weibel-Palade Bodies in Primary Human Endothelial Cells

Author

Geelen, Joyce, van den Biggelaar, Maartje, Linssen, Peter, van der Velden, Thea, Mertens, Koenraad, Monnens, Leo, Pharmaceutics, Sub Pharmaceutical proteins, Pharmaceutics, and Sub Pharmaceutical proteins

Subjects
Original Paper, biology, Endothelial cells, Other Research Radboud Institute for Molecular Life Sciences [Radboudumc 0], Stimulation, Shiga toxin, von Willebrand factor, lcsh:Diseases of the genitourinary system. Urology, lcsh:RC870-923, Exocytosis, Microbiology, Cell biology, Pathogenesis, fluids and secretions, Thrombin, Von Willebrand factor, Nephrology, cardiovascular system, biology.protein, medicine, Weibel–Palade body, Weibel-Palade bodies, Intracellular, medicine.drug
Abstract

Background/Aims: Diarrhea-associated hemolytic uremic syndrome is associated with the presence of Shiga toxin (Stx1, Stx2 and several variants) in the circulation. The aim of this study is to examine the possible triggering effect of Stx1 on the exocytosis of Weibel-Palade bodies (WPbs). Methods: Cultured human umbilical venous endothelial cells (HUVECs) and glomerular microvascular endothelial cells (GMVECs) were stimulated by thrombin and Stx1 in both static and flowing conditions. The amount of secreted von Willebrand factor (VWF) in the supernatant as well as the remaining intracellular fraction was determined. Results: In HUVECs and in 2 out of 4 GMVECs, the stimulation of Stx1 in flow at 1 dyne/cm2 resulted in a decrease of intracellular VWF. This is contrary to the results of Stx1 applied in static conditions. At a higher flow rate of 5 dyne/cm2, no effect in GMVECs was observed. Conclusion: Stx1 can contribute, via an effect on WPbs, to the exocytosis of WPbs in flow conditions in HUVECs and probably in GMVECs. This results in the release of VWF, suggesting an initiating role of the coagulation system in the pathogenesis.

Published
2014

33. Switch in FGFR 3 and 4 expression profile during human renal development may account for transient hypercalcemia in patients with Sotos syndrome due to 5q35 microdeletions.: Ontogeny of FGFR 3 and 4 in human kidney

Author

Mutsaers, Henricus, Levtchenko, Elena, Martinerie, Laetitia, Pertijs, Jeanne, Allegaert, Karel, Devriendt, Koenraad, Masereeuw, Rosalinde, Monnens, Leo, Lombes, Marc, Récepteurs stéroïdiens : physiopathologie endocrinienne et métabolique, Université Paris-Sud - Paris 11 (UP11)-IFR93-Institut National de la Santé et de la Recherche Médicale (INSERM), Department of Pharmacology and Toxicology, Radboud University Medical Center [Nijmegen], Department of Pediatrics & Department of Growth and Regeneration, Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven)-University Hospitals Leuven [Leuven], departement of Pharmacology, Radboud University, Radboud University Medical Center [Nijmegen]-Radboud University Medical Center [Nijmegen], Centre for Human Genetics, Department of Physiology, PremUp Foundation, Institut de Recherche pour le Développement (IRD)-Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-CHI Créteil-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), European Renal Association - European Dialysis and Transplant Association (ERA-EDTA, Fellowship no. ERA STF 132-2013, Grant Agreement 1801110N and 1800214N, respectively)., and Lombes, Marc

Subjects
musculoskeletal diseases, [SDV.MHEP.EM] Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism, [SDV.MHEP.EM]Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism
Abstract

International audience; : Context: Sotos syndrome is a rare genetic disorder with a distinct phenotypic spectrum including overgrowth and learning difficulties. Here we describe a new case of Sotos syndrome with a 5q35 microdeletion, affecting the fibroblast growth factor receptor 4 (FGFR4) gene, presenting with infantile hypercalcemia. Objective: We strived to elucidate the evanescent nature of the observed hypercalcemia by studying the ontogenesis of FGFR3 and FGFR4 - which are both associated with FGF23-mediated mineral homeostasis - in the developing human kidney. Design: RT-qPCR and immunohistochemical analyses were used on archival human kidney samples to investigate expression of the FGFR signaling pathway during renal development. Results: We demonstrated that renal gene and protein expression of both FGFRs increased during fetal development between the gestational ages (GA) of 14-40 weeks. Yet, FGFR4 expression increased more rapidly as compared to FGFR3 (slope: 0.047 vs. 0.0075, p = 0.0018). Moreover, gene and protein expression of the essential FGFR co-receptor, Klotho, also increased with a significant positive correlation between FGFR and Klotho mRNA expression during renal development. Interestingly, we found that perinatal FGFR4 expression (GA 38-40 weeks) was 7-fold higher as compared to FGFR3 (p=0.0035), while in adult kidney tissues, FGFR4 gene expression level was more than 2-fold lower compared to FGFR3 (p=0.0029), thus identifying a molecular developmental switch of FGFR isoforms. Conclusion: We propose that the heterozygous FGFR4 deletion, as observed in the Sotos syndrome patient, leads to a compromised FGF23 signaling during infancy accounting for transient hypercalcemia. These findings represent a novel and intriguing view on FGF23-mediated calcium homeostasis.

Published
2014

35. Switch in FGFR3 and -4 expression profile during human renal development may account for transient hypercalcemia in patients with Sotos syndrome due to 5q35 microdeletions

Author

Sub General Pharmacology, Pharmacology, Mutsaers, Henricus A M, Levtchenko, Elena N, Martinerie, Laetitia, Pertijs, Jeanne C L M, Allegaert, Karel, Devriendt, Koenraad, Masereeuw, Roos|info:eu-repo/dai/nl/155644033, Monnens, Leo A H, Lombès, Marc, Sub General Pharmacology, Pharmacology, Mutsaers, Henricus A M, Levtchenko, Elena N, Martinerie, Laetitia, Pertijs, Jeanne C L M, Allegaert, Karel, Devriendt, Koenraad, Masereeuw, Roos|info:eu-repo/dai/nl/155644033, Monnens, Leo A H, and Lombès, Marc

Published
2014

36. The effect of shiga toxin on weibel-palade bodies in primary human endothelial cells

Author

Pharmaceutics, Sub Pharmaceutical proteins, Geelen, Joyce, van den Biggelaar, Maartje, Linssen, Peter, van der Velden, Thea, Mertens, Koenraad, Monnens, Leo, Pharmaceutics, Sub Pharmaceutical proteins, Geelen, Joyce, van den Biggelaar, Maartje, Linssen, Peter, van der Velden, Thea, Mertens, Koenraad, and Monnens, Leo

Published
2014

39. Mutation analysis and clinical implications of von Willebrand factor-cleaving protease deficiency.

Author

UCL - MD/GYPE - Département de gynécologie, d'obstétrique et de pédiatrie, Assink, Karin, Schiphorst, Rikke, Allford, Sarah, Karpman, Diana, Etzioni, Amos, Brichard, Bénédicte, van de Kar, Nicole, Monnens, Leo, van den Heuvel, Lambertus, UCL - MD/GYPE - Département de gynécologie, d'obstétrique et de pédiatrie, Assink, Karin, Schiphorst, Rikke, Allford, Sarah, Karpman, Diana, Etzioni, Amos, Brichard, Bénédicte, van de Kar, Nicole, Monnens, Leo, and van den Heuvel, Lambertus

Abstract

BACKGROUND: The pentad of thrombocytopenia, hemolytic anemia, mild renal dysfunction, neurologic signs, and fever, classically characterizes the syndrome of thrombotic thrombocytopenic purpura (TTP). TTP usually occurs in adults as an acquired form but a congenital form in children has also been described. In the latter case, the initial presentation is often with neonatal jaundice and thrombocytopenia. The disorder may subsequently take a relapsing course. Deficiency of a recently identified novel metalloprotease, the von Willebrand factor (vWF)-cleaving protease, originating from mutations in the ADAMTS13 gene plays a major role in the development of TTP. METHODS: Blood for DNA analysis was collected from six unrelated TTP families, consisting of nine patients from four different countries, and was screened for mutations in the ADAMTS13 gene. This gene spans 29 exons encompassing approximately 37 kb. Conventional techniques of DNA extraction, polymerase chain reaction (PCR), and direct cycle sequencing were used. RESULTS: Eight novel ADAMTS13 mutations are presented. Half of the total number of mutant ADAMTS13 alleles are amino acid substitutions. The disease-causing mutations are spread over the gene. The pathogenicity of the individual mutations is based upon their predicted effect on the ADAMTS13 protein and segregation in family members. Although most of the patients (seven out of nine) had symptoms during the neonatal period, they were in a remarkably good condition. Only one of the nine patients had a decreased glomerular filtration rate (GFR) with proteinuria and hematuria. Another patient had epileptic seizures. CONCLUSION: We confirm that deficiency of ADAMTS13 is a molecular mechanism responsible for familial TTP. An early diagnosis allows prophylactic treatment with fresh plasma infusions.

Published
2003

40. Immunosuppression and Renal Outcome in Congenital and Pediatric Steroid-Resistant Nephrotic Syndrome

Author

Büscher, Anja K., primary, Kranz, Birgitta, additional, Büscher, Rainer, additional, Hildebrandt, Friedhelm, additional, Dworniczak, Bernd, additional, Pennekamp, Petra, additional, Kuwertz-Bröking, Eberhard, additional, Wingen, Anne-Margret, additional, John, Ulrike, additional, Kemper, Markus, additional, Monnens, Leo, additional, Hoyer, Peter F., additional, Weber, Stefanie, additional, and Konrad, Martin, additional

Published
2010
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43. Cystine Dimethylester Model of Cystinosis: Still Reliable?

Author

Wilmer, Martijn J, primary, Willems, Peter H, additional, Verkaart, Sjoerd, additional, Visch, Henk-Jan, additional, de Graaf-Hess, Adriana, additional, Blom, Henk J, additional, Monnens, Leo A, additional, van den Heuvel, Lambertus P, additional, and Levtchenko, Elena N, additional

Published
2007
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44. Segmental transport of Ca2+ and Mg2+ along the gastrointestinal tract.

Author

Lameris, Anke L., Nevalainen, Pasi I., Reijnen, Daphne, Simons, Ellen, Eygensteyn, Jelle, Monnens, Leo, Bindels, René J. M., and Hoenderop, Joost G. J.

Subjects
GASTROINTESTINAL system physiology, CALCIUM channels, MAGNESIUM ions, INTESTINAL absorption, HOMEOSTASIS, TRP channels
Abstract

Calcium (Ca2+) and magnesium (Mg2+) ions are involved in many vital physiological functions. Since dietary intake is the only source of minerals for the body, intestinal absorption is essential for normal homeostatic levels. The aim of this study was to characterize the absorption of Ca2+ as well as Mg2+ along the gastrointestinal tract at a molecular and functional level. In both humans and mice the Ca2+ channel transient receptor potential vanilloid subtype 6 (TRPV6) is expressed in the proximal intestinal segments, whereas Mg2+ channel transient receptor potential melastatin subtype 6 (TRPM6) is expressed in the distal parts of the intestine. A method was established to measure the rate of Mg2+ absorption from the intestine in a time-dependent manner by use of 25Mg2+. In addition, local absorption of Ca2+ and Mg2+ in different segments of the intestine of mice was determined by using surgically implanted intestinal cannulas. By these methods, it was demonstrated that intestinal absorption of Mg2+ is regulated by dietary needs in a vitamin D-independent manner. Also, it was shown that at low luminal concentrations, favoring transcellular absorption, Ca2+ transport mainly takes place in the proximal segments of the intestine, whereas Mg2+ absorption predominantly occurs in the distal part of the gastrointestinal tract. Vitamin D treatment of mice increased serum Mg2+ levels and 24-h urinary Mg2+ excretion, but not intestinal absorption of 25Mg2+. Segmental cannulation of the intestine and time-dependent absorption studies using 25Mg2+ provide new ways to study intestinal Mg2+ absorption. [ABSTRACT FROM AUTHOR]

Published
2015
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