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Sjaastad O, Blau N, Rydning SL, Peters V, Rødningen O, Stray-Pedersen A, Krossnes B, Tallaksen C, Koht J. Homocarnosinosis: A historical update and findings in the SPG11 gene. Acta Neurol Scand 2018; 138:245-250. [PMID: 29732542 DOI: 10.1111/ane.12949] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2018] [Indexed: 11/28/2022]
Abstract
OBJECTIVES A family with homocarnosinosis was reported in the literature in 1976. Three affected siblings had spastic paraplegia, retinitis pigmentosa, mental retardation, and cerebrospinal fluid (CSF) homocarnosine concentrations 20 times higher than in controls. Based on the clinical findings and new genetic techniques, we have been able to establish a precise genetic diagnosis. METHOD The medical records were re-evaluated, and genetic analyses were performed post-mortem in this original family. SNP array-based whole genome homozygosity mapping and Sanger sequencing of the SPG11 gene were performed. Seven additional Norwegian SPG11 patients and their disease-causing variants and clinical findings were evaluated. Homocarnosine levels in CSF were measured in four of these seven patients. RESULTS A homozygous pathogenic splice-site variant in the SPG11 gene, c.2316 + 1G>A, was found. The clinical findings in the original family correlate with the heterogeneous SPG11 phenotype. The same variant was found in seven other Norwegian SPG11 patients, unrelated to the original family, either as homozygous or compound heterozygous constellation. Normal homocarnosine levels were found in the CSF of all unrelated SPG11 patients. CONCLUSIONS A re-evaluation of the clinical symptoms and findings in the original family correlates with the SPG11 phenotype. The increased levels of homocarnosine do not seem to be a biomarker for SPG11 in our patients. Homocarnosinosis is still a biochemical aberration with unknown clinical significance.
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Affiliation(s)
- O. Sjaastad
- Department of Neurology; St.Olavs Hospital; Trondheim University Hospital; Trondheim Norway
| | - N. Blau
- Centre for Pediatric and Adolescence Medicine; University of Heidelberg; Heidelberg Germany
| | - S. L. Rydning
- Department of Neurology; Oslo University Hospital; Oslo Norway
- Institute of Clinical Medicine; University of Oslo; Oslo Norway
| | - V. Peters
- Centre for Pediatric and Adolescence Medicine; University of Heidelberg; Heidelberg Germany
| | - O. Rødningen
- Department of Medical Genetics; Oslo University Hospital; Oslo Norway
| | - A. Stray-Pedersen
- Norwegian National Unit for Newborn Screening at Division of Pediatric and Adolescent Medicine; Oslo University Hospital; Oslo Norway
- Institute of Clinical Medicine; University of Oslo; Oslo Norway
| | - B. Krossnes
- Department of Pathology; Oslo University Hospital; Oslo Norway
| | - C. Tallaksen
- Department of Neurology; Oslo University Hospital; Oslo Norway
- Institute of Clinical Medicine; University of Oslo; Oslo Norway
| | - J. Koht
- Department of Neurology; Drammen Hospital; Vestre Viken Hospital Trust; Drammen Norway
- Institute of Clinical Medicine; University of Oslo; Oslo Norway
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van Wegberg AMJ, MacDonald A, Ahring K, Bélanger-Quintana A, Blau N, Bosch AM, Burlina A, Campistol J, Feillet F, Giżewska M, Huijbregts SC, Kearney S, Leuzzi V, Maillot F, Muntau AC, van Rijn M, Trefz F, Walter JH, van Spronsen FJ. The complete European guidelines on phenylketonuria: diagnosis and treatment. Orphanet J Rare Dis 2017; 12:162. [PMID: 29025426 PMCID: PMC5639803 DOI: 10.1186/s13023-017-0685-2] [Citation(s) in RCA: 381] [Impact Index Per Article: 54.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 07/11/2017] [Indexed: 12/22/2022] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive inborn error of phenylalanine metabolism caused by deficiency in the enzyme phenylalanine hydroxylase that converts phenylalanine into tyrosine. If left untreated, PKU results in increased phenylalanine concentrations in blood and brain, which cause severe intellectual disability, epilepsy and behavioural problems. PKU management differs widely across Europe and therefore these guidelines have been developed aiming to optimize and standardize PKU care. Professionals from 10 different European countries developed the guidelines according to the AGREE (Appraisal of Guidelines for Research and Evaluation) method. Literature search, critical appraisal and evidence grading were conducted according to the SIGN (Scottish Intercollegiate Guidelines Network) method. The Delphi-method was used when there was no or little evidence available. External consultants reviewed the guidelines. Using these methods 70 statements were formulated based on the highest quality evidence available. The level of evidence of most recommendations is C or D. Although study designs and patient numbers are sub-optimal, many statements are convincing, important and relevant. In addition, knowledge gaps are identified which require further research in order to direct better care for the future.
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Affiliation(s)
- A. M. J. van Wegberg
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - A. MacDonald
- Dietetic Department, Birmingham Children’s Hospital, Birmingham, UK
| | - K. Ahring
- Department of PKU, Kennedy Centre, Glostrup, Denmark
| | - A. Bélanger-Quintana
- Metabolic Diseases Unit, Department of Paediatrics, Hospital Ramon y Cajal Madrid, Madrid, Spain
| | - N. Blau
- University Children’s Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany
- University Children’s Hospital Zürich, Zürich, Switzerland
| | - A. M. Bosch
- Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, The Netherlands
| | - A. Burlina
- Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy
| | - J. Campistol
- Neuropaediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain
| | - F. Feillet
- Department of Paediatrics, Hôpital d’Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France
| | - M. Giżewska
- Department of Paediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology of the Developmental Age, Pomeranian Medical University, Szczecin, Poland
| | - S. C. Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, The Netherlands
| | - S. Kearney
- Clinical Psychology Department, Birmingham Children’s Hospital, Birmingham, UK
| | - V. Leuzzi
- Department of Paediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Via dei Sabelli 108, 00185 Rome, Italy
| | - F. Maillot
- CHRU de Tours, Université François Rabelais, INSERM U1069, Tours, France
| | - A. C. Muntau
- University Children’s Hospital, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - M. van Rijn
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - F. Trefz
- Department of Paediatrics, University of Heidelberg, Heidelberg, Germany
| | - J. H. Walter
- Medicine, Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - F. J. van Spronsen
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
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3
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MacDonald A, Ahring K, Almeida MF, Belanger-Quintana A, Blau N, Burlina A, Cleary M, Coskum T, Dokoupil K, Evans S, Feillet F, Giżewska M, Gokmen Ozel H, Lotz-Havla AS, Kamieńska E, Maillot F, Lammardo AM, Muntau AC, Puchwein-Schwepcke A, Robert M, Rocha JC, Santra S, Skeath R, Strączek K, Trefz FK, van Dam E, van Rijn M, van Spronsen F, Vijay S. The challenges of managing coexistent disorders with phenylketonuria: 30 cases. Mol Genet Metab 2015; 116:242-51. [PMID: 26498184 DOI: 10.1016/j.ymgme.2015.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 10/06/2015] [Accepted: 10/07/2015] [Indexed: 11/16/2022]
Abstract
INTRODUCTION The few published case reports of co-existent disease with phenylketonuria (PKU) are mainly genetic and familial conditions from consanguineous marriages. The clinical and demographic features of 30 subjects with PKU and co-existent conditions were described in this multi-centre, retrospective cohort study. METHODS Diagnostic age of PKU and co-existent condition, treatment regimen, and impact of co-existent condition on blood phenylalanine (Phe) control and PKU management were reported. RESULTS 30 patients (11 males and 19 females), with PKU and a co-existent condition, current median age of 14 years (range 0.4 to 40 years) from 13 treatment centres from Europe and Turkey were described. There were 21 co-existent conditions with PKU; 9 were autoimmune; 6 gastrointestinal, 3 chromosomal abnormalities, and 3 inherited conditions. There were only 5 cases of parental consanguinity. Some patients required conflicting diet therapy (n=5), nutritional support (n=7) and 5 children had feeding problems. There was delayed diagnosis of co-existent conditions (n=3); delayed treatment of PKU (n=1) and amenorrhea associated with Grave's disease that masked a PKU pregnancy for 12 weeks. Co-existent conditions adversely affected blood Phe control in 47% (n=14) of patients. Some co-existent conditions increased the complexity of disease management and increased management burden for patients and caregivers. CONCLUSIONS Occurrence of co-existent disease is not uncommon in patients with PKU and so investigation for co-existent disorders when the clinical history is not completely consistent with PKU is essential. Integrating care of a second condition with PKU management is challenging.
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Affiliation(s)
| | - K Ahring
- Center for PKU, The Kennedy Centre, University Hospital, Glostrup, Copenhagen, Denmark
| | - M F Almeida
- Centro de Genética Médica Doutor Jacinto de Magalhães, CHP EPE, Porto, Portugal; Unit for Multidisciplinary Research in Biomedicine, Abel Salazar Institute of Biomedical Sciences, University of Porto-UMIB/ICBAS/UP, Porto, Portugal
| | | | - N Blau
- Dietmar-Hopp Metabolic Center, University Children's Hospital, Heidelberg, Germany
| | - A Burlina
- Division of Inherited Metabolic Diseases, University Hospital, Padua, Italy
| | - M Cleary
- Hospital for Sick Children, Great Ormond Street, London, UK
| | - T Coskum
- Department of Inherited Metabolic Disorders, Hacettepe University, Ankara, Turkey
| | - K Dokoupil
- Department of Metabolism and Nutrition, Dr. von Hauner Children's Hospital, University of Munich, Munich, Germany
| | - S Evans
- The Children's Hospital, Birmingham, UK
| | - F Feillet
- Hôpital d'enfants Brabois, Vandoeuvre les Nancy, France
| | - M Giżewska
- Department of Pediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology, Pomeranian Medical University, Szczecin, Poland
| | - H Gokmen Ozel
- Department of Nutrition and Dietetics, Hacettepe University, Ankara, Turkey
| | - A S Lotz-Havla
- Dr. von Hauner Children's Hospital, University of Munich, Munich, Germany
| | - E Kamieńska
- Department of Paediatrics and Haematology, Pomeranian Medical University, Szczecin, Poland
| | - F Maillot
- CHRU de Tours, service de medicine interne, Université François Rabelais, Tours, France
| | - A M Lammardo
- Depart Ped, San Paolo Hosp Univ Milan, Milan, Italy
| | - A C Muntau
- University Children's Hospital, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | | | - M Robert
- Hôpital Universitaire des Enfants Reine Fabiola, Brussels, Belgium
| | - J C Rocha
- Centro de Genética Médica Doutor Jacinto de Magalhães, CHP EPE, Porto, Portugal; Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Portugal
| | - S Santra
- The Children's Hospital, Birmingham, UK
| | - R Skeath
- Hospital for Sick Children, Great Ormond Street, London, UK
| | - K Strączek
- Department of Pediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology, Pomeranian Medical University, Szczecin, Poland
| | - F K Trefz
- Division of Inborn Metabolic Diseases, University Children's Hospital, Heidelberg, Germany
| | - E van Dam
- Section of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - M van Rijn
- Section of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - F van Spronsen
- Section of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - S Vijay
- The Children's Hospital, Birmingham, UK
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Koht J, Rengmark A, Opladen T, Bjørnarå KA, Selberg T, Tallaksen CME, Blau N, Toft M. Clinical and genetic studies in a family with a novel mutation in the sepiapterin reductase gene. Acta Neurol Scand 2014:7-12. [PMID: 24588500 DOI: 10.1111/ane.12230] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Sepiapterin reductase deficiency is a rare, but treatable inherited disorder of tetrahydrobiopterin and neurotransmitter metabolism. This disorder is most probably underdiagnosed. To date, only 44 cases have been described in the literature. We present the clinical and genetic investigations in a family with a complex movement disorder. MATERIALS AND METHODS We examined two affected sisters and three healthy family members. The cerebrospinal fluid was analyzed for neurotransmitter and pterins, and the sepiapterin reductase gene (SPR) was sequenced. RESULTS The sisters had a complex movement disorders with dystonia and diurnal fluctuations. Both had oculogyric crises, and the older sister also hypersomnia. Both sisters had raised prolactin levels twice above the reference level. One sister had a dramatic response to levodopa, the other responded, but developed dyskinesia despite low doses. Both patients improved dramatically over time with levodopa (2.3 and 1.5 mg/kg/day). Very low levels of homovanillic acid and 5-hydroxyindoleacetic acid and increased levels of sepiapterin and dihydrobiopterin were measured in the cerebrospinal fluid before treatment. DNA analyses revealed a novel homozygous mutation in exon 2 in the SPR gene, c.364A>G/p.(Tyr123Cys), located in a highly conserved region in the gene. Both parents and the healthy sister were carriers for the same mutation. CONCLUSIONS A new homozygous mutation in the SPR gene was found in two sisters with dopa-responsive dystonia. This important and treatable neurotransmitter disorder must be considered in patients with a complex movement disorder with diurnal fluctuations with or without intellectual impairment. Patients with these symptoms should undergo levodopa trial, cerebrospinal fluid investigations, and genetic analyses.
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Affiliation(s)
- J. Koht
- Department of Neurology; Drammen Hospital; Vestre Viken Health Trust; Drammen Norway
| | - A. Rengmark
- Department of Neurology; Oslo University Hospital; Rikshospitalet; Oslo Norway
| | - T. Opladen
- Department of General Pediatrics; University of Heidelberg; Heidelberg Germany
| | - K. A. Bjørnarå
- Department of Neurology; Drammen Hospital; Vestre Viken Health Trust; Drammen Norway
| | - T. Selberg
- Department of Habilitation; Drammen Hospital; Vestre Viken Health Trust; Drammen Norway
| | - C. M. E. Tallaksen
- Faculty of Medicine; University of Oslo; Oslo Norway
- Department of Neurology; Oslo University Hospital; Ullevål Norway
| | - N. Blau
- Department of General Pediatrics; University of Heidelberg; Heidelberg Germany
| | - M. Toft
- Department of Neurology; Oslo University Hospital; Rikshospitalet; Oslo Norway
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Affiliation(s)
- M. E. Blaskovics
- Kaiser Permanente Medicai Center, 9985 Sierra Avenue, Fontana, California 92335, U. S. A
| | - T. A. Giudici
- Childrens Hospital, Division of Medical Genetics, Los Angeles, California, USA
| | - N. Blau
- University Children's Hospital, Zurich, Switzerland
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6
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Affiliation(s)
- M. Spada
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - T. Parrella
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - R. Ponzone
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - S. Ferraris
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - O. Guardamagna
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - A. Ponzone
- Istituto di Clinica Pediatrica, Piazza Polonia 94, 10126 Torino, Italy
| | - N. Blau
- Department of Pediatrics, University of Zürich, CH-8032 Zürich, Switzerland
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7
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Guardamagna O, Spada M, Ponzone A, Viora E, Ponzone R, Binkert F, Matasovic A, Kierat L, Blau N. Prenatal Diagnosis of Dihydropteridine Reductase Deficiency in a Twin Pregnancy. Pteridines 2013. [DOI: 10.1515/pteridines.1991.3.12.19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- O. Guardamagna
- Department of Pediatrics Piazza Polonia, 94, 10126 Torino Italy
| | - M. Spada
- of Pediatrics Piazza Polonia, 94, 10126 Torino Italy
| | - A. Ponzone
- Department of Pediatrics Piazza Polonia, 94, 10126 Torino Italy
| | - E. Viora
- Department of Obstetrics and Gynecology, Piazza Polonia, 94, 10126 Torino Italy
| | - R. Ponzone
- Department of Obstetrics and Gynecology, Piazza Polonia, 94, 10126 Torino Italy
| | - F. Binkert
- Institute of Medical Genetics University of Zürich, Switzerland
| | - A. Matasovic
- Department of Pediatrics, University of Zürich, Switzerland
| | - L. Kierat
- Department of Pediatrics, University of Zürich, Switzerland
| | - N. Blau
- Department of Pediatrics, University of Zürich, Switzerland
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8
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Affiliation(s)
- J. Guzman
- Division of Clinical Chemistry, Department of Pediatrics, University of Zürich, CH-8032 Zürich, Switzerland
| | - N. Blau
- Division of Clinical Chemistry, Department of Pediatrics, University of Zürich, CH-8032 Zürich, Switzerland
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9
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Artner-Dworzak E, Blau N, Fuchs D, Reibnegger G. Abstracts. Eighteenth International Winter-Workshop on Chemical, Biochemical and Clinical Aspects of Pteridines. Pteridines 2013. [DOI: 10.1515/pteridines.1999.10.2.47] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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10
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Zimmermann M, Jacobs P, Fingerhut R, Torresani T, Thöny B, Blau N, Baumgartner MR, Rohrbach M. Positive effect of a simplified diet on blood phenylalanine control in different phenylketonuria variants, characterized by newborn BH4 loading test and PAH analysis. Mol Genet Metab 2012; 106:264-8. [PMID: 22607939 DOI: 10.1016/j.ymgme.2012.04.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 04/18/2012] [Indexed: 11/15/2022]
Abstract
Until today, the mainstay of phenylketonuria (PKU) treatment is a phenylalanine (Phe)-restricted diet. Strict dietary treatment decreases flexibility and autonomy and still has a major impact on patients and their families. Compliance is often poor, particularly in adolescence. The aim of this study was to investigate the effect of the intake of fruits and vegetables containing Phe less than 100 mg/100g ('simplified diet'), as recommended by WHO for all individuals, instead of classical totally restricted diet on the course and treatment control of the disease in a well-characterized PKU cohort (n=80). All individual blood Phe measurements of each patient (1992-2009) were statistically analyzed before and after diet switch. Epidemiological data, age at diagnosis, PAH mutations, BH(4) responsiveness, as well as Phe control measurements and detailed diet information were tabulated in a local database. 62.5% had BH4 loading test and 40% had PAH analysis; 50/80 switched from classical to simplified diet, including 26 classical PKU, 13 moderate PKU, 7 mild PKU and 4 mild hyperphenylalaninemia (HPA). Median Phe levels on a simplified diet did not differ significantly to the median Phe levels on classical diet in all disease groups. Our results indicate that a simplified diet has no negative effect on blood Phe control in patients with hyperphenylalaninemia, independent of severity of the phenotype or the age at diet switch, over the period of 3 years. Thus, a simpler approach to dietary treatment of PKU available to all HPA patients is more likely to be accepted and adhered by patients and might also increase quality of life.
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Affiliation(s)
- M Zimmermann
- Division of Metabolism, University Children's Hospital and Children's Research Center, Zurich, Switzerland
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11
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Vanderver A, Tonduti D, Lebon P, Blau N, Loewenstein J, Gahl W, Toro C, Hyland K. Neurotransmitter Abnormalities and Response to L-Dopa in SPG11 (P05.133). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p05.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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12
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Dill P, Wagner M, Somerville A, Thöny B, Blau N, Weber P. Child neurology: paroxysmal stiffening, upward gaze, and hypotonia: hallmarks of sepiapterin reductase deficiency. Neurology 2012; 78:e29-32. [PMID: 22291068 DOI: 10.1212/wnl.0b013e3182452849] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- P Dill
- Division of Pediatric Neurology and Developmental Medicine, University Children's Hospital, Basel, Switzerland.
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13
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Brun L, Ngu LH, Keng WT, Ch'ng GS, Choy YS, Hwu WL, Lee WT, Willemsen MAAP, Verbeek MM, Wassenberg T, Régal L, Orcesi S, Tonduti D, Accorsi P, Testard H, Abdenur JE, Tay S, Allen GF, Heales S, Kern I, Kato M, Burlina A, Manegold C, Hoffmann GF, Blau N. Clinical and biochemical features of aromatic L-amino acid decarboxylase deficiency. Neurology 2010; 75:64-71. [PMID: 20505134 DOI: 10.1212/wnl.0b013e3181e620ae] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe the current treatment; clinical, biochemical, and molecular findings; and clinical follow-up of patients with aromatic l-amino acid decarboxylase (AADC) deficiency. METHOD Clinical and biochemical data of 78 patients with AADC deficiency were tabulated in a database of pediatric neurotransmitter disorders (JAKE). A total of 46 patients have been previously reported; 32 patients are described for the first time. RESULTS In 96% of AADC-deficient patients, symptoms (hypotonia 95%, oculogyric crises 86%, and developmental retardation 63%) became clinically evident during infancy or childhood. Laboratory diagnosis is based on typical CSF markers (low homovanillic acid, 5-hydroxyindoleacidic acid, and 3-methoxy-4-hydroxyphenolglycole, and elevated 3-O-methyl-l-dopa, l-dopa, and 5-hydroxytryptophan), absent plasma AADC activity, or elevated urinary vanillactic acid. A total of 24 mutations in the DDC gene were detected in 49 patients (8 reported for the first time: p.L38P, p.Y79C, p.A110Q, p.G123R, p.I42fs, c.876G>A, p.R412W, p.I433fs) with IVS6+ 4A>T being the most common one (allele frequency 45%). CONCLUSION Based on clinical symptoms, CSF neurotransmitters profile is highly indicative for the diagnosis of aromatic l-amino acid decarboxylase deficiency. Treatment options are limited, in many cases not beneficial, and prognosis is uncertain. Only 15 patients with a relatively mild form clearly improved on a combined therapy with pyridoxine (B6)/pyridoxal phosphate, dopamine agonists, and monoamine oxidase B inhibitors.
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Affiliation(s)
- L Brun
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zürich, Switzerland.
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14
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Willemsen MA, Verbeek MM, Kamsteeg EJ, de Rijk-van Andel JF, Aeby A, Blau N, Burlina A, Donati MA, Geurtz B, Grattan-Smith PJ, Haeussler M, Hoffmann GF, Jung H, de Klerk JB, van der Knaap MS, Kok F, Leuzzi V, de Lonlay P, Megarbane A, Monaghan H, Renier WO, Rondot P, Ryan MM, Seeger J, Smeitink JA, Steenbergen-Spanjers GC, Wassmer E, Weschke B, Wijburg FA, Wilcken B, Zafeiriou DI, Wevers RA. Tyrosine hydroxylase deficiency: a treatable disorder of brain catecholamine biosynthesis. Brain 2010; 133:1810-22. [DOI: 10.1093/brain/awq087] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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15
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de Groot MJ, Hoeksma M, Blau N, Reijngoud DJ, van Spronsen FJ. Pathogenesis of cognitive dysfunction in phenylketonuria: review of hypotheses. Mol Genet Metab 2010; 99 Suppl 1:S86-9. [PMID: 20123477 DOI: 10.1016/j.ymgme.2009.10.016] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Revised: 10/15/2009] [Accepted: 10/19/2009] [Indexed: 11/23/2022]
Abstract
In untreated phenylketonuria (PKU), deficiency of phenylalanine hydroxylase (PAH) results in elevated blood phenylalanine (Phe) concentrations and severe mental retardation. Current dietary treatment prevents mental retardation, but cognitive outcome remains suboptimal. The mechanisms by which elevated blood Phe concentrations disturb cerebral metabolism and cognitive function have not been fully elucidated. In this review, we discuss different hypotheses on the pathogenesis of PKU, focusing on the effects of disturbed large neutral amino acid (LNAA) transport from blood to brain on cerebral neurotransmitter and protein synthesis. Although the definitive roles of these processes in PKU pathogenesis are not fully understood yet, both substantially influence clinical outcome.
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Affiliation(s)
- M J de Groot
- Beatrix Children's Hospital, University Medical Center Groningen, Groningen, The Netherlands
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Kusmierska K, Jansen EEW, Jakobs C, Szymanska K, Malunowicz E, Meilei D, Thony B, Blau N, Tryfon J, Rokicki D, Pronicka E, Sykut-Cegielska J. Sepiapterin reductase deficiency in a 2-year-old girl with incomplete response to treatment during short-term follow-up. J Inherit Metab Dis 2009; 32 Suppl 1:S5-10. [PMID: 19130291 DOI: 10.1007/s10545-008-1009-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Revised: 10/11/2008] [Accepted: 10/15/2008] [Indexed: 11/25/2022]
Abstract
Sepiapterin reductase (SR) catalyses the last step in the tetrahydrobiopterin biosynthesis pathway; it converts 6-pyruvoyl-tetrahydropterin (6-PTP) to BH(4) in an NADPH-dependent reaction. SR deficiency is a very rare autosomal recessive disorder with normal phenylalanine (Phe) concentration in blood and diagnostic abnormalities are detected in CSF. We present a 16-month-old girl with SR deficiency. From the newborn period she presented with an adaptation regulatory disorder. At the age of 3 months, abnormal eye movements with dystonic signs and at 4.5 months psychomotor retardation were noticed. Since that time axial hypotonia with limb spasticity (or rather delayed reflex development), gastro-oesophageal reflux and fatigue at the end of the day has been observed. Brain MRI was normal; EEG was without epileptiform discharges. Analysis of biogenic amine metabolites in CSF at the age of 16 months showed very low HVA and 5-HIAA concentrations. Analysis of CSF pterins revealed strongly elevated dihydrobiopterin (BH(2)), slightly elevated neopterin and elevated sepiapterin levels. Plasma and CSF amino acids concentrations were normal. A phenylalanine loading test showed increased Phe after 1 h, 2 h and 4 h and very high Phe/Tyr ratios. SR deficiency was confirmed in fibroblasts and a novel homozygous g.1330C>G (p.N127K) SPR mutation was identified. On L-dopa and then additionally 5-hydroxytryptophan, the girl showed slow but remarkable progress in motor and intellectual ability. Now, at the age of 3 years, she is able to sit; expressive speech is delayed (to 1 1/2 years), passive speech is well developed. Her visual-motor skills, eye-hand coordination and social development correspond to the age of 2 1/2 years.
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Affiliation(s)
- K Kusmierska
- Department of Biochemistry and Experimental Medicine, The Children's Memorial Health Institute, Al. Dzieci Polskich 20, 04-830, Warsaw, Poland.
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17
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Vatanavicharn N, Kuptanon C, Liammongkolkul S, Liu TT, Hsiao KJ, Ratanarak P, Blau N, Wasant P. Novel mutation affecting the pterin-binding site of PTS gene and review of PTS mutations in Thai patients with 6-pyruvoyltetrahydropterin synthase deficiency. J Inherit Metab Dis 2009; 32 Suppl 1:S279-82. [PMID: 19830588 DOI: 10.1007/s10545-009-1221-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 07/30/2009] [Accepted: 08/25/2009] [Indexed: 10/20/2022]
Abstract
Tetrahydrobiopterin (BH(4)) deficiency comprises heterogeneous disorders resulting in hyperphenylalaninaemia (HPA) and lack of monoamine neurotransmitters. Among these, 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is the most common disorder. We report a female Thai patient with PTPS deficiency who was initially detected by newborn screening for HPA, and later treated by supplements of BH(4), L-dopa/carbidopa, and 5-hydroxytryptophan. Monitoring of serum prolactin representing dopamine sufficiency is used for optimizing the dosage of L-dopa. She showed a remarkable progress of development despite delayed treatment at 5 months of age. Mutation analysis revealed two heterozygous missense mutations of the PTS gene: c.259C>T (p.P87S) inherited from the father; and c.147T>G (p.H49Q) inherited from the mother. The latter is a novel mutation that affects the pterin-binding site of the PTPS enzyme. This novel mutation expands the mutation spectrum of PTPS deficiency. Notably, some PTS mutations have been reported in both Thai and Chinese patients. Whether these common mutations are the result of a founder effect with common ancestors of Thai and Chinese people or intermarriage between Thai and Chinese descents in Thailand remain unclear. In conclusion, severe neurological impairment from BH(4) deficiency could be prevented by newborn screening for HPA and proper metabolic management. However, pterin analysis for early diagnosis of BH(4) deficiency is still not available in most developing countries.
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Affiliation(s)
- N Vatanavicharn
- Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, 2 Prannok Road, Bangkoknoi, Bangkok, Thailand.
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18
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Gramer G, Garbade SF, Blau N, Lindner M. Pharmacokinetics of tetrahydrobiopterin following oral loadings with three single dosages in patients with phenylketonuria. J Inherit Metab Dis 2009; 32:52-7. [PMID: 19016342 DOI: 10.1007/s10545-008-0955-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Revised: 08/20/2008] [Accepted: 09/11/2008] [Indexed: 11/25/2022]
Abstract
BACKGROUND Tetrahydrobiopterin (BH(4)) loading has been performed for many years in patients detected by newborn screening for hyperphenylalaninaemia (HPA) to distinguish BH(4) cofactor synthesis or recycling defects from phenylalanine hydroxylase (PAH)-deficient HPA. Previous studies have shown that the pharmacokinetics of BH(4) shows high intra-individual and inter-individual variability. METHODS Seventeen adult patients with PAH-deficient HPA were classified in one of three phenotypic groups (mild, moderate, classical PKU) according to their response to a standardized protein loading test. Genotype information was available for all participants. In a randomized controlled double-blind design, BH(4) loadings in single oral dosages of 10, 20 and 30 mg BH(4)/kg body weight (bw) were performed to assess BH(4) responsiveness. As part of this study, levels of BH(4) metabolites in dried blood spots were studied to provide information on the pharmacokinetics of BH(4) following oral administration. RESULTS Levels of biopterin and pterin (B + P) increased significantly with increasing BH(4) dose (p < 0.0001). Maximum B + P levels were reached 4 hours after application of BH(4). There was no significant difference in BH(4) pharmacokinetics between the three phenotypic groups of PKU. Male and female patients showed different levels of BH(4) metabolites following 10 mg BH(4)/kg bw, but not following 20 and 30 mg BH(4)/kg bw. There was no relationship between age of patients and BH(4) pharmacokinetics. There was no correlation between B + P levels and decrease in Phe level (p = 0.69). CONCLUSION BH(4) pharmacokinetics are variable between patients regarding absolute levels of BH(4) metabolites reached after BH(4) loading, but are similar regarding the interval to individual maximum B + P levels. Levels of B + P increase significantly with increasing BH(4) doses. There is no correlation between B + P levels and decrease in Phe level.
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Affiliation(s)
- G Gramer
- Centre for Paediatric and Adolescent Medicine, Department of General Paediatrics, Division of Metabolic Disorders, Heidelberg, Germany.
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19
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Abstract
BACKGROUND Tetrahydrobiopterin (BH(4)) is a potential new orphan drug for the treatment of some patients with phenylketonuria (PKU), mostly mild forms. Numerous studies have confirmed this finding and BH(4)-responsiveness may be predicted to some extent from the corresponding genotype. AIM To investigate the response to BH(4) loading test, the phenylalanine hydroxylase (PAH) mutations and the long-term therapeutic efficacy of BH(4) in patients with PKU, and to better define BH(4)-responsive patients according to phenylalanine (Phe) levels and dietary phenylalanine tolerance. METHODS 30 Italian PKU patients (age range: 6 months-24 years; 12 female, 18 male) were included in this retrospective study. Eleven out of 30 patients presented with Phe levels below 450 micromol/L and 19 patients with Phe levels between 450 and 900 micromol/L. In the second group, we investigated the effect of long-term (6 months-7 years) oral administration of BH(4) on blood Phe levels and daily Phe tolerance. RESULTS In all patients with initial blood Phe levels <450 micromol/L (n = 11), BH(4) loading test was positive, but no treatment was introduced. In 12 out of 19 patients with blood Phe levels >450 micromol/L and positive at BH(4) loading, the treatment with BH(4) (10 mg/kg per day) was initiated. Before BH(4) treatment, Phe tolerance was less than 700 mg/day in all patients except for one (patient no. 9), increasing to 2-3-fold (from 498 +/- 49 to 1475 +/- 155 mg/day) on BH(4) treatment. In these patients the amino acid mixture supplementation was stopped and the diet was a combination of low-protein foods and natural proteins, mostly from animal sources. CONCLUSION Long-term BH(4) substitution (up to 7 years) in a group of moderate PKU patients allowed a substantial relaxation of the dietary restrictions or even replacement of the diet with BH(4) without any adverse effects.
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Affiliation(s)
- A Burlina
- Metabolic Unit, Division of Metabolic Diseases, Department of Pediatrics, University Hospital, Padua, Italy.
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20
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Leuzzi V, Carducci CA, Carducci CL, Pozzessere S, Burlina A, Cerone R, Concolino D, Donati MA, Fiori L, Meli C, Ponzone A, Porta F, Strisciuglio P, Antonozzi I, Blau N. Phenotypic variability, neurological outcome and genetics background of 6-pyruvoyl-tetrahydropterin synthase deficiency. Clin Genet 2009; 77:249-57. [PMID: 20059486 DOI: 10.1111/j.1399-0004.2009.01306.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study aimed to investigate the clinical variability and factors implied in the outcome of 6-pyruvoyl-tetrahydropterin synthase deficiency (PTPSd). Biochemical and clinical phenotype, treatment variables, and 6-pyruvoyl-tetrahydropterin synthase (PTS) genotype, were explored retrospectively in 19 Italian patients (12 males and 7 females, aged 4 months to 33 years). According to the level of biogenic amines in cerebrospinal fluid (CSF) at the diagnosis, the patients were classified as mild (6) (normal level) or severe (13) (abnormal low level) form (MF and SF, respectively). Blood Phe ranged from 151 to 1053 micromol/l in MF (mean +/- SD: 698 +/- 403) and 342-2120 micromol/l in SF (mean +/- SD: 1175 +/- 517) (p = 0.063). Patients with MF showed a normal neurological development (a transient dystonia was detected in one), while all SF patients except one presented with severe neurological impairment and only four had a normal neurological development. The outcome of the SF was influenced by the precocity of the treatment. Serial CSF examinations revealed a decline of 5-hydroxyindolacetic acid in MFs and an incomplete restoration of neurotransmitters in SFs: neither obviously affected the prognosis. PTS gene analysis detected 17 different mutations (seven so far unreported) (only one affected allele was identified in three subjects). A good correlation was found between genotype and clinical and biochemical phenotype. The occurrence of brain neurotransmitter deficiency and its early correction (by the therapy) are the main prognostic factors in PTPSd.
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Affiliation(s)
- V Leuzzi
- Department of Child Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy.
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21
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Garcia-Cazorla A, Quadros EV, Nascimento A, Garcia-Silva MT, Briones P, Montoya J, Ormazábal A, Artuch R, Sequeira JM, Blau N, Arenas J, Pineda M, Ramaekers VT. Mitochondrial diseases associated with cerebral folate deficiency. Neurology 2008; 70:1360-2. [PMID: 18413591 DOI: 10.1212/01.wnl.0000309223.98616.e4] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- A Garcia-Cazorla
- Neurology Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Passeig Sant Joan de Déu, 2, 08950 Esplugues, Barcelona, Spain.
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22
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Cosentino F, Hürlimann D, Delli Gatti C, Chenevard R, Blau N, Alp NJ, Channon KM, Eto M, Lerch P, Enseleit F, Ruschitzka F, Volpe M, Lüscher TF, Noll G. Chronic treatment with tetrahydrobiopterin reverses endothelial dysfunction and oxidative stress in hypercholesterolaemia. Heart 2008; 94:487-92. [PMID: 17916662 DOI: 10.1136/hrt.2007.122184] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Reduced availability of tetrahydrobiopterin (BH(4)), an essential cofactor of nitric oxide (NO) synthase (NOS), decreases NO production and increases reactive oxygen species. Both mechanisms contribute to atherosclerotic vascular disease. Although acute supplementation of BH(4) improves endothelial dysfunction, the effect of chronic BH(4) in humans is unknown. OBJECTIVE To investigate the effect of chronic BH(4) supplementation on endothelial function and oxidative stress in hypercholesterolaemia. DESIGN Randomised double-blind, placebo-controlled trial. SETTING University Hospital. PATIENTS 22 hypercholesterolaemic patients (low-density lipoprotein (LDL) >4.5 mmol/l) were randomised to 4 weeks of oral BH(4) (400 mg twice daily) or placebo. Age-matched healthy volunteers served as controls. MAIN OUTCOME MEASURES Endothelium-dependent and -independent vasodilatation was assessed by venous occlusion plethysmography. To elucidate the mechanisms of BH(4) effect, NO release and superoxide anion (O(2)(-)) production were measured in human aortic endothelial cells exposed to native LDL (2.6 mmol cholesterol/l). RESULTS BH(4) plasma levels were significantly increased by oral supplementation. NO-mediated vasodilatation to acetylcholine was reduced in patients compared with controls and restored by BH(4). No effect of BH(4) on endothelium-independent vasodilatation was seen. Furthermore, 8-F(2 )isoprostane plasma levels, a marker of vascular oxidative stress, were reduced by BH(4). In LDL-treated endothelial cells, BH(4) levels and NO release were reduced and O(2)(-) production increased compared with control cells. Exogenous BH(4) normalised NO and O(2)(-) production. CONCLUSIONS In hypercholesterolaemia, endothelial dysfunction and oxidative stress can be reversed by chronic oral treatment with BH(4). Thus, BH(4) availability is essential for maintaining NO synthesis and low O(2)(-) production by endothelial NOS in vivo, and may provide a rational therapeutic approach to prevent cardiovascular disease.
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Affiliation(s)
- F Cosentino
- Cardiovascular Centre, University Hospital, Rämistrasse 100, CH-8091 Zurich, Switzerland
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23
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Ramaekers VT, Blau N, Sequeira JM, Nassogne MC, Quadros EV. Folate receptor autoimmunity and cerebral folate deficiency in low-functioning autism with neurological deficits. Neuropediatrics 2007; 38:276-81. [PMID: 18461502 DOI: 10.1055/s-2008-1065354] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Reduced folate transport to the CNS was identified in two autism spectrum disorders, i.e., Rett syndrome and infantile low-functioning autism with neurological abnormalities. Twenty-five patients with early-onset low-functioning autism with or without neurological deficits, were evaluated for serum folate, cerebrospinal fluid (CSF) 5-methyltetrahydrofolate (5MTHF), and serum FR autoantibodies of the blocking type to determine the significance of folate receptor (FR) autoantibodies with respect to folate transport across the blood-CSF barrier. In spite of normal serum folate, CSF 5MTHF was low in 23 of 25 patients. The reduced CSF folate in 19 of these 23 patients could be explained by serum FR autoantibodies blocking the folate binding site of the membrane-attached FR on the choroid epithelial cells. Oral folinic acid supplements led to normal CSF 5MTHF and partial or complete clinical recovery after 12 months. Serum FR autoimmunity appears to represent an important factor in the pathogenesis of reduced folate transport to the nervous system among children with early-onset low-functioning autism associated with or without neurological deficits. Early detection of FR autoantibodies may be a key factor in the prevention and therapeutic intervention among this subgroup of patients with autism.
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Affiliation(s)
- V T Ramaekers
- Division of Child Neurology, University Hospital Liège, Belgium.
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24
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Ramaekers VT, Sequeira JM, Artuch R, Blau N, Temudo T, Ormazabal A, Pineda M, Aracil A, Roelens F, Laccone F, Quadros EV. Folate receptor autoantibodies and spinal fluid 5-methyltetrahydrofolate deficiency in Rett syndrome. Neuropediatrics 2007; 38:179-83. [PMID: 18058624 DOI: 10.1055/s-2007-991148] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Rett syndrome was associated with low cerebrospinal fluid (CSF) 5-methyltetrahydrofolate (5MTHF) in 42-50% of European patients whereas approximately 93% of the patients from North-America had a normal CSF 5MTHF status. We determined the CSF folate status in Rett patients living in North- and South-Western Europe and measured serum folate receptor (FR) autoantibodies of the blocking type to explain the reduced folate transport across the choroid plexus. Irrespective of their MECP2 genotype and despite normal plasma folate values, 14 of 33 Rett patients (42%) had low CSF folate levels. Blocking FR autoantibodies were found in 8 of the Rett patients (24%), 6 of whom had low CSF folate levels. FR autoimmunity was primarily found within the group of Rett patients with low CSF folate status with a higher incidence in North-Western Europe. In Rett patients from North-America 74 of 76 girls had higher folate values in both serum and CSF than European patients. The food folate fortification in North-America may account for the higher folate levels and may prevent CFD in these Rett patients. FR autoimmunity occurred predominantly in Rett patients from North-Western Europe and may contribute to cerebral folate deficiency (CFD).
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Affiliation(s)
- V T Ramaekers
- Division of Pediatric Neurology, University Hospital Aachen, Germany.
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25
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Abstract
Folate transport to the brain depends on ATP-driven folate receptor-mediated transport across choroid plexus epithelial cells. Failure of ATP production in Kearns-Sayre syndrome syndrome provides one explanation for the finding of low spinal fluid (CSF) 5-methyltetrahydrofolate (5MTHF) levels in this condition. Therefore, we suspect the presence of reduced folate transport across the blood-spinal fluid barrier in other mitochondrial encephalopathies. In the present patient with mitochondrial complex I encephalomyopathy a low 5-methyltetrahydrofolate level was found in the CSF. Serum folate receptor autoantibodies were negative and could not explain the low spinal fluid folate levels. The epileptic seizures did not respond to primidone monotherapy, but addition of ubiquinone-10 and radical scavengers reduced seizure frequency. Add-on treatment with folinic acid led to partial clinical improvement including full control of epilepsy, followed by marked recovery from demyelination of the brainstem, thalamus, basal ganglia and white matter. Cerebral folate deficiency is not only present in Kearns-Sayre syndrome but may also be secondary to the failure of mitochondrial ATP production in other mitochondrial encephalopathies. Treatment with folinic acid in addition to supplementation with radical scavengers and cofactors of deficient respiratory enzymes can result in partial clinical improvement and reversal of abnormal myelination patterns on neuro-imaging.
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Affiliation(s)
- V T Ramaekers
- Division of Pediatric Neurology, University Hospital, RWTH Aachen, Germany.
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26
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Abstract
We report an adult patient lacking endogenous synthesis of monoamines (dopamine, serotonin, and catecholamines) due to a severe dihydropteridine reductase (DHPR) deficiency. With levodopa and 5-hydroxytryptophan (5HTP) supplementation, the patient exhibited moderate mental retardation, acute episodes of parkinsonism, and episodes of depression. Despite the use of levodopa from age 3 months, he exhibited no dyskinesia or dopaminergic cell loss as suggested by normal PET imaging of the dopamine transporter.
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Affiliation(s)
- F Sedel
- Fédération des maladies du système nerveux, Groupe Hospitalier Pitié-Salpêtrière, 47 Boulevard de l'Hôpital, 75651 Paris cedex 13, France.
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27
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Zurflüh MR, Fiori L, Fiege B, Ozen I, Demirkol M, Gärtner KH, Thöny B, Giovannini M, Blau N. Pharmacokinetics of orally administered tetrahydrobiopterin in patients with phenylalanine hydroxylase deficiency. J Inherit Metab Dis 2006; 29:725-31. [PMID: 17091341 DOI: 10.1007/s10545-006-0425-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 09/27/2006] [Accepted: 09/28/2006] [Indexed: 10/23/2022]
Abstract
The oral loading test with tetrahydrobiopterin (BH(4)) is used to discriminate between variants of hyperphenylalaninaemia and to detect BH(4)-responsive patients. The outcome of the loading test depends on the genotype, dosage of BH(4), and BH(4) pharmacokinetics. A total of 71 patients with hyperphenylalaninaemia (mild to classic) were challenged with BH(4) (20 mg/kg) according to different protocols (1 x 20 mg or 2 x 20 mg) and blood BH(4) concentrations were measured in dried blood spots at different time points (T(0), T(2), T(4), T(8), T(12), T(24), T(32) and T(48 h)). Maximal BH(4) concentrations (median 22.69 nmol/g Hb) were measured 4 h after BH(4) administration in 63 out of 71 patients. Eight patients presented with maximal BH(4) concentrations approximately 44% higher at 8 h than at 4 h. After 24 h, BH(4) blood concentrations dropped to 11% of maximal values. This profile was similar using different protocols. The following pharmacokinetic parameters were calculated for BH(4) in blood: t (max) = 4 h, AUC (T(0-32)) = 370 nmol x h/g Hb, and t (1/2) for absorption (1.1 h), distribution (2.5 h), and elimination (46.0 h) phases. Maximal BH(4) blood concentrations were not significantly lower in non-responders and there was no correlation between blood concentrations and responsiveness. Of mild PKU patients, 97% responded to BH(4) administration, while one was found to be a non-responder. Only 10/19 patients (53%) with Phe concentrations of 600-1200 mumol/L responded to BH(4) administration, and of the patients with the severe classical phenotype (blood Phe > 1200 mumol/L) only 4 out of 17 patient responded. An additional 36 patients with mild hyperphenylalaninaemia (HPA) who underwent the combined loading test with Phe+BH(4) were all responders. Slow responders and non-responders were found in all groups of HPA.
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Affiliation(s)
- M R Zurflüh
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Zurich, Switzerland
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28
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Moretti P, Sahoo T, Hyland K, Bottiglieri T, Peters S, del Gaudio D, Roa B, Curry S, Zhu H, Finnell RH, Neul JL, Ramaekers VT, Blau N, Bacino CA, Miller G, Scaglia F. Cerebral folate deficiency with developmental delay, autism, and response to folinic acid. Neurology 2006; 64:1088-90. [PMID: 15781839 DOI: 10.1212/01.wnl.0000154641.08211.b7] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors describe a 6-year-old girl with developmental delay, psychomotor regression, seizures, mental retardation, and autistic features associated with low CSF levels of 5-methyltetrahydrofolate, the biologically active form of folates in CSF and blood. Folate and B12 levels were normal in peripheral tissues, suggesting cerebral folate deficiency. Treatment with folinic acid corrected CSF abnormalities and improved motor skills.
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Affiliation(s)
- P Moretti
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
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29
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Van Hove JLK, Steyaert J, Matthijs G, Legius E, Theys P, Wevers R, Romstad A, Møller LB, Hedrich K, Goriounov D, Blau N, Klein C, Casaer P. Expanded motor and psychiatric phenotype in autosomal dominant Segawa syndrome due to GTP cyclohydrolase deficiency. J Neurol Neurosurg Psychiatry 2006; 77:18-23. [PMID: 16361586 PMCID: PMC2117403 DOI: 10.1136/jnnp.2004.051664] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Revised: 03/14/2005] [Accepted: 04/14/2005] [Indexed: 11/04/2022]
Abstract
BACKGROUND Segawa syndrome due to GTP cyclohydrolase deficiency is an autosomal dominant disorder with variable expression, that is clinically characterised by l-dopa responsive, diurnally fluctuating dystonia and parkinsonian symptoms. OBJECTIVE To delineate the neurological and psychiatric phenotype in all affected individuals of three extended families. METHODS GTP cyclohydrolase deficiency was documented by biochemical analyses, enzymatic measurements in fibroblasts, and molecular investigations. All affected individuals were examined neurologically, and psychiatric data were systematically reviewed. RESULTS Eighteen affected patients from three families with proven GTP cyclohydrolase deficiency were identified. Eight patients presenting at less than 20 years of age had typical motor symptoms of dystonia with diurnal variation. Five family members had late-presenting mild dopa-responsive symptoms of rigidity, frequent falls, and tendonitis. Among mutation carriers older than 20 years of age, major depressive disorder, often recurrent, and obsessive-compulsive disorder were strikingly more frequent than observed in the general population. Patients responded well to medication increasing serotonergic neurotransmission and to l-dopa substitution. Sleep disorders including difficulty in sleep onset and maintenance, excessive sleepiness, and frequent disturbing nightmares were present in 55% of patients. CONCLUSION Physicians should be aware of this expanded phenotype in affected members of families with GTP cyclohydrolase deficiency.
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Affiliation(s)
- J L K Van Hove
- Department of Pediatrics, University of Colorado Health Sciences Center, Denver, CO, USA.
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30
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Hjermind LE, Johannsen LG, Blau N, Wevers RA, Lucking CB, Hertz JM, Friberg L, Regeur L, Nielsen JE, Sørensen SA. Hereditary dystonia or parkinson – a patient with both – and problems concerning diagnostic, treatment and genetic counselling. Akt Neurol 2005. [DOI: 10.1055/s-2005-916298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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31
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Saunders-Pullman R, Blau N, Hyland K, Zschocke J, Nygaard T, Raymond D, Shanker V, Mohrmann K, Arnold L, Tabbal S, deLeon D, Ford B, Brin M, Chouinard S, Ozelius L, Klein C, Bressman SB. Phenylalanine loading as a diagnostic test for DRD: interpreting the utility of the test. Mol Genet Metab 2004; 83:207-12. [PMID: 15542391 DOI: 10.1016/j.ymgme.2004.07.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Revised: 07/15/2004] [Accepted: 07/19/2004] [Indexed: 11/28/2022]
Abstract
Phenylalanine loading has been proposed as a diagnostic test for autosomal dominant DRD (dopa-responsive dystonia), and recently, a phenylalanine/tyrosine (phe/tyr) ratio of 7.5 after 4 h was reported as diagnostic of DRD. To test the utility of this test in another sample with DRD, we administered an oral challenge of phenylalanine (100 mg/kg) to 11 individuals with DRD and one non-manifesting gene carrier. Only 6/12 had a 4 h phe/tyr ratio of greater than 7.5, suggesting that additional parameters must be set to avoid missing the diagnosis of DRD, including the need for the plasma phenylalanine to reach a minimum level 600 in order for the test to be valid. We propose that in cases where this minimum plasma phenylalanine level is not reached, plasma tetrahydrobiopterin should be measured or alternatively other symptomatic family members should be screened.
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Abstract
The authors report the long-term course of two siblings with L-dopa responsive dystonia (DRD) associated with a compound heterozygous mutation in the tyrosine hydroxylase (TH) gene. Both siblings manifested with lower-limb onset generalized DRD and had a sustained response to low-dose L-dopa therapy for over 35 years. Although the l-dopa therapy was delayed up to 20 years after disease onset, there were no cognitive or neurologic sequelae of the long-term catecholamine deficit.
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Affiliation(s)
- A Schiller
- Department of Neurology, University Hospital Zürich, Zürich, Switzerland
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Abstract
We report on the long-term follow-up of the first Italian patient with the tetrahydrobiopterin (BH4)-responsive type of phenylalanine hydroxylase deficiency (R243X/Y414C genotype). The patient was diagnosed by the newborn screening for phenylketonuria (PKU) and with a positive BH4 loading test. Introduction of BH4 (initially 10 and later 20 mg/kg/day) in addition to reduced low-phenylalanine diet resulted in therapeutic plasma phenylalanine concentrations (<340 micromol/L). Very good compliance and no side effects in this patient demonstrate the great potential of BH4 in the treatment of some patients with mild PKU.
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Affiliation(s)
- R Cerone
- Department of Pediatrics, G. Gaslini Institute, University of Genoa, Genoa, Italy.
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Blau N, Bonafé L, Krägeloh-Mann I, Thöny B, Kierat L, Häusler M, Ramaekers V. Cerebrospinal fluid pterins and folates in Aicardi-Goutières syndrome: a new phenotype. Neurology 2003; 61:642-7. [PMID: 12963755 DOI: 10.1212/01.wnl.0000082726.08631.e7] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe three unrelated children with a distinctive variant of Aicardi-Goutières syndrome (AGS) characterized by microcephaly, severe mental and motor retardation, dyskinesia or spasticity, and occasional seizures. RESULTS Neuroimaging showed bilateral calcification of basal ganglia and white matter. CSF glucose, protein, cell count, and interferon alpha were normal. Abnormal CSF findings included extremely high neopterin (293 to 814 nmol/L; normal 12 to 30 nmol/L) and biopterin (226 to 416 nmol/L; normal 15 to 40 nmol/L) combined with lowered 5-methyltetrahydrofolate (23 to 48 nmol/L; normal 64 to 182 nmol/L) concentrations in two patients. The absence of pleocytosis and normal CSF interferon alpha was a characteristic finding compared to the classic AGS syndrome. Genetic and enzymatic tests excluded disorders of tetrahydrobiopterin metabolism, including mutation analysis of GTP cyclohydrolase feed-back regulatory protein. CSF investigations in three patients with classic AGS also showed increased pterins and partially lowered folate levels. CONCLUSIONS Intrathecal overproduction of pterins is the first biochemical abnormality identified in patients with AGS variants. Long-term substitution with folinic acid (2-4 mg/kg/day) resulted in substantial clinical recovery with normalization of CSF folates and pterins in one patient and clinical improvement in another. The underlying defect remains unknown.
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Affiliation(s)
- N Blau
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Zurich, Switzerland.
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35
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Ramaekers VT, Hansen SI, Holm J, Opladen T, Senderek J, Häusler M, Heimann G, Fowler B, Maiwald R, Blau N. Reduced folate transport to the CNS in female Rett patients. Neurology 2003; 61:506-15. [PMID: 12939425 DOI: 10.1212/01.wnl.0000078939.64774.1b] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Previous CSF studies in Rett syndrome suggest reduced turnover of the biogenic monoamines serotonin and dopamine. Because diminished turnover may result from CNS folate depletion, the authors studied transport of folate across the blood-brain barrier. METHODS In four patients with Rett syndrome, the authors measured CSF values of 5-methyltetrahydrofolate (5MTHF), biogenic monoamine end-metabolites, and pterins together with serum and red blood cell folate. In CSF, the overall folate binding capacity by the two soluble folate-binding proteins FBP1 and FBP2 (sFBP) was measured using a radioligand binding method for H3-labeled folate. A specific immunoreactive test (ELISA) detected sFBP1, which normally contributes to 30 to 35% of the total folate binding capacity. Genetic analysis included DNA sequencing of the MECP2, FBP1, and FBP2 genes. Empirical treatment with oral folinic acid was evaluated. RESULTS Two patients without and two with mutations of the MECP2 gene had normal values for red blood cell folate, serum folate, homocysteine, and methionine. In CSF, all patients had low values for 5MTHF, neopterin, and the serotonin end-metabolite 5-hydroxyindoleacetic acid (5-HIAA). Genetic analysis of FBP1 and FBP2 genes had normal results. Compared to controls, patients with Rett syndrome had normal immunoreactive sFBP1 in CSF, whereas the total folate binding capacity was disproportionately lowered. Empirical treatment with oral folinic acid normalized 5-MHTF and 5-HIAA levels in CSF, and led to partial clinical improvement. CONCLUSION Irrespective of the MECP2 genotype, 5MTHF transfer to the CNS is reduced in Rett syndrome. Folinic acid supplementation restores 5MTHF levels and serotoninergic turnover. The lowered folate binding capacity of FBP is not explained by a defect of the FBP1 or FBP2 gene, but most likely occurs as a secondary phenomenon in Rett syndrome.
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Affiliation(s)
- V T Ramaekers
- Division of Pediatric Neurology, Department of Pediatrics, University Hospital Aachen, Germany.
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37
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Blau N, Stuckwisch C. Additions and Corrections - The Conjugative Effect of the Dimethylsulfonio Group in an Aliphatic System. J Org Chem 2003. [DOI: 10.1021/jo01363a650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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38
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Nardocci N, Zorzi G, Blau N, Fernandez Alvarez E, Sesta M, Angelini L, Pannacci M, Invernizzi F, Garavaglia B. Neonatal dopa-responsive extrapyramidal syndrome in twins with recessive GTPCH deficiency. Neurology 2003; 60:335-7. [PMID: 12552057 DOI: 10.1212/01.wnl.0000044049.99690.ad] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors report two twin sisters, age 15 years, with recessive GTP cyclohydrolase deficiency, who presented with neonatal onset of rigidity, tremor, and dystonia but with no other symptoms suggestive of a diffuse CNS involvement. The plasma phenylalanine levels were normal. Treatment with L-dopa/carbidopa, started at age 1 year, was associated with sustained recovery from all neurologic signs. The patients were homozygous for a new recessive mutation in the GHI gene.
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MESH Headings
- Adolescent
- Antiparkinson Agents/therapeutic use
- Basal Ganglia Diseases/complications
- Basal Ganglia Diseases/diagnosis
- Basal Ganglia Diseases/drug therapy
- Basal Ganglia Diseases/enzymology
- Carbidopa/therapeutic use
- Dopamine Agents/therapeutic use
- Dystonia/etiology
- Female
- Follow-Up Studies
- GTP Cyclohydrolase/deficiency
- GTP Cyclohydrolase/genetics
- Genes, Recessive
- Homozygote
- Humans
- Infant, Newborn
- Infant, Newborn, Diseases/diagnosis
- Infant, Newborn, Diseases/drug therapy
- Infant, Newborn, Diseases/genetics
- Levodopa/therapeutic use
- Metabolism, Inborn Errors/diagnosis
- Metabolism, Inborn Errors/drug therapy
- Muscle Rigidity/etiology
- Mutation
- Reflex, Abnormal/genetics
- Remission Induction
- Treatment Outcome
- Tremor/etiology
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Affiliation(s)
- N Nardocci
- Department of Child Neurology, Istituto Nazionale Neurologico "Carlo Besta," Milan, Italy.
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39
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Ramaekers VT, Häusler M, Opladen T, Heimann G, Blau N. Psychomotor retardation, spastic paraplegia, cerebellar ataxia and dyskinesia associated with low 5-methyltetrahydrofolate in cerebrospinal fluid: a novel neurometabolic condition responding to folinic acid substitution. Neuropediatrics 2002; 33:301-8. [PMID: 12571785 DOI: 10.1055/s-2002-37082] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Normal brain development and function depend on the active transport of folates across the blood-brain barrier. The folate receptor-1 (FR 1) protein is localized at the basolateral surface of the choroid plexus, which is characterized by a high binding affinity for circulating 5-methyltetrahydrofolate (5-MTHF). PATIENTS AND METHODS We report on the clinical and metabolic findings among five children with normal neurodevelopmental progress during the first four to six months followed by the acquisition of a neurological condition which includes marked irritability, decelerating head growth, psychomotor retardation, cerebellar ataxia, dyskinesias (choreoathetosis, ballism), pyramidal signs in the lower limbs and occasional seizures. After the age of six years the two oldest patients also manifested a central visual disorder. Known disorders have been ruled out by extensive investigations. Cerebrospinal fluid (CSF) analysis included determination of biogenic monoamines, pterins and 5-MTHF. RESULTS Despite normal folate levels in serum and red blood cells with normal homocysteine, analysis of CSF revealed a decline towards very low values for 5-methyltetrahydrofolate (5-MTHF), which suggested disturbed transport of folates across the blood-brain barrier. Genetic analysis of the FR 1 gene revealed normal coding sequences. Oral treatment with doses of the stable compound folinic acid (0.5-1 mg/kg/day Leucovorin(R)) resulted in clinical amelioration and normalization of 5-MTHF values in CSF. CONCLUSION Our findings identified a new condition manifesting after the age of 6 months which was accompanied by low 5-MTHF in cerebrospinal fluid and responded to oral supplements with folinic acid. However, the cause of disturbed folate transfer across the blood-brain barrier remains unknown.
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Affiliation(s)
- V T Ramaekers
- Division of Paediatric Neurology, Department of Paediatrics, University Hospital Aachen, Aachen, Germany.
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40
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Bardelli T, Donati MA, Gasperini S, Ciani F, Belli F, Blau N, Morrone A, Zammarchi E. Two novel genetic lesions and a common BH4-responsive mutation of the PAH gene in Italian patients with hyperphenylalaninemia. Mol Genet Metab 2002; 77:260-6. [PMID: 12409276 DOI: 10.1016/s1096-7192(02)00166-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Hyperphenylalaninemia (HPA), due to a deficiency of phenylalanine hydroxylase (PAH) enzyme, is caused by mutations in the PAH gene. Molecular analysis in 23 Italian patients with PAH deficiency identified two novel (P281R, L287V) and 20 previously described genetic lesions in the PAH gene. The detection of the A403V amino acid substitution in combination with null mutations in patients with BH4-responsive PAH deficiency leads us to correlate it with BH4 responsiveness.
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Affiliation(s)
- T Bardelli
- Metabolic and Neuromuscular Unit, Department of Pediatrics, University of Florence, Florence, Italy
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41
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Abstract
We report two new patients with tetrahydrobiopterin (BH4)-responsive phenylketonuria and compare their phenylalanine hydroxylase (PAH) genotypes (A395P/ IVS12+g>a and R261Q/165T, respectively) to those of previous cases from the literature. These case observations confirm earlier reports stating that BH4-responsive patients are frequently carriers of a missense mutation within the DNA region coding for the catalytic domain of the enzyme. Interestingly, many of the PAH gene mutations detected in BH4-responsive patients have been associated with an inconsistent phenotype in the past. Our case reports confirm that it is necessary to thoroughly examine individuals with increased phenylalanine levels, not only to detect BH4 deficiency, but also to identify patients with PAH deficiency who may benefit from BH4 treatment. In both of our patients, however, an effect of BH4 (7.5 mg/kg) on plasma phenylalanine levels was not seen in the newborn period. We therefore conclude that a normal neonatal BH4 test does not necessarily exclude BH4 responsiveness in all such patients.
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Affiliation(s)
- U Lässker
- Department of General Paediatrics, University of Kiel, Germany.
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42
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Milardović S, Grabarić Z, Rumenjak V, Blau N, Milosević D. Use of a ruthenium(III), iron(II), and nickel(II) hexacyanometallate-modified graphite electrode with immobilized oxalate oxidase for the determination of urinary oxalate. J AOAC Int 2001; 84:1927-33. [PMID: 11767164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
This paper describes the performance of a biosensor with an Ru(III), Ni(II), and Fe(II) hexacyanometallate-modified graphite electrode and immobilized oxalate oxidase for the determination of urinary oxalate. The addition of ruthenium enhances the electrochemical reversibility and chemical stability of the electrocrystallized layer and improves the sensitivity of the biosensor. Hydrogen peroxide, produced by the enzyme-catalyzed oxidation of oxalate, was measured at -50 mV vs an Hg Hg2CI2 3M KCl electrode in a solution of pH 3.6 succinic buffer, 0.1 M KCl, and 5.4mM ethylenediaminetetraacetic acid. The linear concentration range for the determination of oxalate was 0.18-280 microM. The recoveries of added oxalate (10-35 microM) from aqueous solution ranged from 99.5 to 101.7%, whereas from urine samples without oxalate (or with a concentration of oxalate below the detection limit) the recoveries of added oxalate ranged from 91.4 to 106.6%. The oxalate in 24 h urine samples, taken during their daily routine from 35 infants and children, was measured and found to range from 0.6 to 121.7 mg/L. There were no interferences from uric acid, acetylsalicylic acid, and urea in the concentration range investigated, but paracetamol and ascorbic acid did interfere. A good correlation (R2 = 0.9242) was found between values obtained for oxalate in real urine samples by 2 laboratories, with the proposed biosensor and ion chromatography, respectively.
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Affiliation(s)
- S Milardović
- University of Zagreb, Faculty of Chemical Engineering and Technology, Croatia
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43
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Abstract
The authors describe a case of neurologic involvement in mild hyperphenylalaninemia (HPA), not due to tetrahydrobiopterin (BH(4)) deficiency, with low levels of monoamine neurotransmitter metabolites in CSF. The combined BH(4)-Phe loading test suggested a BH(4) response, confirmed by clinical improvement after BH(4) therapy. Molecular study revealed a compound heterozygosity of the phenylalanine hydroxylase alleles: a mild HPA-associated mutation (T380M) and the new mutation D151E. This case demonstrates that even mild HPA, generally considered a benign disorder, may present neurologic impairment.
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Affiliation(s)
- L Bonafé
- Division of Clinical Chemistry, Department of Pediatrics, University Children's Hospital, Zürich, Switzerland
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44
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Blau N, Bonafé L, Thöny B. Tetrahydrobiopterin deficiencies without hyperphenylalaninemia: diagnosis and genetics of dopa-responsive dystonia and sepiapterin reductase deficiency. Mol Genet Metab 2001; 74:172-85. [PMID: 11592814 DOI: 10.1006/mgme.2001.3213] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
DOPA responsive dystonia (DRD) and sepiapterin reductase (SR) deficiency are inherited disorders of tetrahydrobiopterin (BH4) metabolism characterized by the signs and symptoms related to monoamine neurotransmitter deficiency. In contrast to classical forms of BH4 deficiency DRD and SR deficiency present without hyperphenylalaninemia and thus cannot be detected by the neonatal screening for phenylketonuria (PKU). While DRD is mostly caused by autosomal dominant mutations in the GTP cyclohydrolase I gene (GCH1), SR deficiency is an autosomal recessive disease. The most important biochemical investigations for the diagnosis of these neurological diseases includes CSF investigations for neurotransmitter metabolites and pterins as well as neopterin and biopterin production in cytokine-stimulated fibroblasts. Discovery of SR deficiency opened new insights into alternative pathways of the cofactor BH4 via carbonyl, aldose, and dihydrofolate reductases. As a consequence of the low dihydrofolate reductase activity in the brain, dihydrobiopterin intermediate accumulates and inhibits tyrosine and tryptophan hydroxylases and uncouples nitric oxide synthase (nNOS), leading to neurotransmitter deficiency and possibly also to neuronal cell death.
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Affiliation(s)
- N Blau
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Steinwiesstrasse 75, Zurich, 8032, Switzerland.
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Sarkissian A, Babloyan A, Arikyants N, Hesse A, Blau N, Leumann E. Pediatric urolithiasis in Armenia: a study of 198 patients observed from 1991 to 1999. Pediatr Nephrol 2001; 16:728-32. [PMID: 11511987 DOI: 10.1007/s004670100647] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2001] [Accepted: 04/24/2001] [Indexed: 10/27/2022]
Abstract
To study prospectively the risk factors and etiology of urolithiasis in all stone patients aged <15 years admitted from 1991 to 1999 to the Arabkir hospital in Yerevan. Stones were obtained by surgery (64%), extracorporeal shockwave lithotripsy (ESWL) (7%) or cystoscopic extraction (4%); 25% passed spontaneously. All were examined by infrared spectroscopy, and spot urines were analyzed chemically. 198 patients, 180 (68% males) with renal stones and 18 (83% males) with primary bladder stones, were studied. Calcium oxalate (CaOx) was the predominant constituent in 62% of the kidney stones, followed by struvite (17%), calcium phosphate (7%), uric acid (7%), ammonium acid urate (5%), and cystine (2%). Bladder stones contained CaOx in 72%, uric acid in 22% and ammonium acid urate in 6% of patients. Etiology was obviously metabolic in 5% and possibly metabolic in 26%. Twenty percent of stones were infectious, and 19% were endemic (9% bladder and 10% kidney stones); 4% were secondary to urinary stasis with malformation but no infection. Etiology in 26% remained unknown. Stone composition and metabolic etiology are similar to that in central Europe and North America. In contrast, infectious calculi and particularly endemic stones are still common, although becoming less so now. Urolithiasis in Armenia thus reflects the transition from a rural to an urban society.
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Spaapen LJ, Bakker JA, Velter C, Loots W, Rubio-Gozalbo ME, Forget PP, Dorland L, De Koning TJ, Poll-The BT, Ploos van Amstel HK, Bekhof J, Blau N, Duran M, Rubio-Gonzalbo ME. Tetrahydrobiopterin-responsive phenylalanine hydroxylase deficiency in Dutch neonates. J Inherit Metab Dis 2001; 24:352-8. [PMID: 11486900 DOI: 10.1023/a:1010596317296] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Four neonates with a positive phenylalanine screening test (Phe concentrations between 258 and 1250 micromol/L) were investigated further to differentiate between phenylalanine hydroxylase (PAH) deficiency and variant hyperphenylalaninaemia (HPA) forms. In patients 1 and 2 a tetrahydrobiopterin (BH4) load caused a significant decrease of the plasma Phe levels. A combined phenylalanine/BH4 loading test was performed in patients 2, 3 and 4. In the latter two patients, plasma Phe concentrations completely normalized within 8 h after the BH4 load (20 mg/kg). Basal urinary pterins were normal in all four patients. The activity of dihydropteridine reductase (DHPR) was normal in patients 1, 2 and 3 and 50% of control values in patient 4 (not in the range of DHPR-deficient patients). In patient 3 a subsequent phenylalanine loading test with concomitant analysis of plasma biopterins revealed a normal increase of biopterin, excluding a BH4 biosynthesis defect. Pterins and neurotransmitter metabolites in CSF of patients 1, 3 and 4 were normal. DNA mutations detected in the PAH gene of patients 1-4 were A313T, and L367fsinsC; V190A and R243X; A300S and A403V; R241C and A403V. The results are suggestive for mutant PAH enzymes with decreased affinity for the cofactor BH4.
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Affiliation(s)
- L J Spaapen
- Department of Biochemical Genetics, Stichting Klinische Genetica Zuid-Oost Nederland, Maastricht.
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47
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Ramaekers VT, Senderek J, Häusler M, Häring M, Abeling N, Zerres K, Bergmann C, Heimann G, Blau N. A novel neurodevelopmental syndrome responsive to 5-hydroxytryptophan and carbidopa. Mol Genet Metab 2001; 73:179-87. [PMID: 11386854 DOI: 10.1006/mgme.2001.3187] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tryptophan hydroxylase (TPH; EC 1.14.16.4) catalyzes the first rate-limiting step of serotonin biosynthesis by converting l-tryptophan to 5-hydroxytryptophan. Serotonin controls multiple vegetative functions and modulates sensory and alpha-motor neurons at the spinal level. We report on five boys with floppiness in infancy followed by motor delay, development of a hypotonic-ataxic syndrome, learning disability, and short attention span. Cerebrospinal fluid (CSF) analysis showed a 51 to 65% reduction of the serotonin end-metabolite 5-hydroxyindoleacetic acid (5HIAA) compared to age-matched median values. In one out of five patients a low CSF 5-methyltetrahydrofolate (MTHF) was present probably due to the common C677T heterozygous mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. Baseline 24-h urinary excretion showed diminished 5HIAA values, not changing after a single oral load with l-tryptophan (50-70 mg/kg), but normalizing after 5-hydroxytryptophan administration (1 mg/kg). Treatment with 5-hydroxytryptophan (4-6 mg/kg) and carbidopa (0.5-1.0 mg/kg) resulted in clinical amelioration and normalization of 5HIAA levels in CSF and urine. In the patient with additional MTHFR heterozygosity, a heterozygous missense mutation within exon 6 (G529A) of the TPH gene caused an exchange of valine by isoleucine at codon 177 (V177I). This has been interpreted as a rare DNA variant because the pedigree analysis did not provide any genotype-phenotype correlation. In the other four patients the TPH gene analysis was normal. In conclusion, this new neurodevelopmental syndrome responsive to treatment with 5-hydroxytryptophan and carbidopa might result from an overall reduced capacity of serotonin production due to a TPH gene regulatory defect, unknown factors inactivating the TPH enzyme, or selective loss of serotonergic neurons.
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Affiliation(s)
- V T Ramaekers
- Division of Paediatric Neurology, Department of Pediatrics, University Hospital Aachen, 52074 Aachen, Germany.
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48
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Skrygan M, Bartholomé B, Bonafé L, Blau N, Bartholomé K. A splice mutation in the GTP cyclohydrolase I gene causes dopa-responsive dystonia by exon skipping. J Inherit Metab Dis 2001; 24:345-51. [PMID: 11486899 DOI: 10.1023/a:1010544316387] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Four different mutations in the GTP cyclohydrolase I gene were found (P199L, M211V, IVS5+1G>A, G203R) in 6 out of 33 families with dopa-responsive dystonia. A splice mutation (IVS5+1G>A) located at the border of exon 5 to intron 5 was found in one of these families. Three members of the family carry the IVS5+1G>A mutation on one allele, inherited from the father to the daughter and son. Examination of the mRNA showed an exon 5 skipping that results in a reduction of enzyme activity in cultured fibroblasts to 4-17% compared to controls. The father and daughter never had clinical symptoms of dopa-responsive dystonia. The son was symptomatic at the age of 3 years and was treated successfully with L-dopa/carbidopa. After 20 years this therapy was terminated and for the next 6 years he was free of symptoms. With increased motoric activity, symptoms reappeared and the therapy was reintroduced.
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Affiliation(s)
- M Skrygan
- University Children's Hospital, Bochum, Germany
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49
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Ehlermann P, Redweik U, Blau N, Heizmann CW, Katus HA, Remppis A. Separation of low molecular weight proteins with SDS-PAGE using taurine as a new trailing ion. Gen Physiol Biophys 2001; 20:203-7. [PMID: 11519691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Taurine as an alternative trailing ion for tricine yields an identical resolution but reduces the running time by 15% and the power consumption by 15% compared to tricine. Therefore cooling of gels is more effective in SDS PAGE with taurine and artefacts due to oxidation of proteins can thus be reduced.
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Affiliation(s)
- P Ehlermann
- Department of Medicine II, Medical University of Lübeck, Germany
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Dudesek A, Röschinger W, Muntau AC, Seidel J, Leupold D, Thöny B, Blau N. Molecular analysis and long-term follow-up of patients with different forms of 6-pyruvoyl-tetrahydropterin synthase deficiency. Eur J Pediatr 2001; 160:267-76. [PMID: 11388593 DOI: 10.1007/s004310000722] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
UNLABELLED The outcome of 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency, the most common form of tetrahydrobiopterin (BH4) deficiency, depends on factors such as severity of the disease, type of mutation, time of diagnosis, and mode of treatment. We investigated five patients from four different families, four of them presenting with the severe form of PTPS deficiency and one with the mild peripheral form. In this study, missense (L26F, T67M, P87L, V124L, D136G, D136V) and nonsense (R15-16ins) mutations were detected by reverse transcriptase polymerase chain reaction and sequence analysis. Two patients with the severe form were compound heterozygotes (T67M/P87L and D136G/R15-16ins), two siblings were homozygous for the D136V mutation, and in the patient with the mild form, heterozygous L26F/V124L mutations were present. Two patients are on combined therapy with L-dopa/carbidopa/5-hydroxytryptophan plus BH4, the siblings are on monotherapy with BH4, and the patient with the mild form is now off treatment, presenting with normal plasma phenylalanine levels. CONCLUSION Long-term follow-up shows that the outcome of 6-pyruvoyl-tetrahydropterin synthase deficiency benefits from treatment started in the first months of life and that the phenotype may change with age. Additionally, depending on the type of mutations, prenatal damage to the fetus may multiply the clinical abnormalities and thus worsen the prognosis of the disease. In patients initially diagnosed with the mild peripheral form of the disease, therapy with tetrahydrobiopterin should be stopped after some time to test whether hyperphenylalaninaemia was only a transient condition.
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Affiliation(s)
- A Dudesek
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Zurich, Switzerland
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