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Alberth H. Van Gennip - One of the best experts on this subject based on the ideXlab platform.
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the application of hplc esi tandem mass spectrometry on urine soaked filter paper strips for the screening of disorders of purine and Pyrimidine Metabolism
Journal of Inherited Metabolic Disease, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Inherited disorders of purine and Pyrimidine Metabolism have a wide variety of clinical presentations that are often non-specific, and severity of individual cases ranges from fatal to asymptomatic. Because of this broad clinical spectrum, a simple, rapid and specific screening method is desired for the diagnosis of these disorders. Several high-performance liquid chromatography (HPLC) methods for screening for these disorders have been reported (Duran et al 1997; Sumi et al 1995), but so far these methods are time-consuming and non-specific. Connection of HPLC with tandem mass spectrometry (MS/MS) has the advantage of rapidity and specificity. We describe an analytical method for routinely screening disorders of purine and Pyrimidine Metabolism on urine-soaked filter-paper strips using reversed-phase HPLC coupled with electrospray ionization (ESI) MS/MS. This method enables easy sample collection, even from the patient's home, mailing and storage (Blau et al 1998; McCann et al 1995).
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rapid screening of high risk patients for disorders of purine and Pyrimidine Metabolism using hplc electrospray tandem mass spectrometry of liquid urine or urine soaked filter paper strips
Clinical Chemistry, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Background: A rapid and specific screening method for patients at risk of inherited disorders of purine and Pyrimidine Metabolism is desirable because symptoms are varied and nonspecific. The aim of this study was to develop a rapid and specific method for screening with use of liquid urine samples or urine-soaked filter paper strips. Methods: Reverse-phase HPLC was combined with electrospray ionization (ESI), tandem mass spectrometry (MS/MS), and detection performed by multiple reaction monitoring. Transitions and instrument settings were established for 17 purines or Pyrimidines. Stable-isotope-labeled reference compounds were used as internal standards when available. Results: Total analysis time of this method was 15 min, approximately one-third that of conventional HPLC with ultraviolet detection. Recoveries were 96–107% in urine with added analyte, with two exceptions (hypoxanthine, 64%; xanthine, 79%), and 89–110% in urine-soaked filter paper strips, with three exceptions (hypoxanthine, 65%; xanthine, 77%; 5-hydroxymethyluracil, 80%). The expected abnormalities were easily found in samples from patients with purine nucleoside phosphorylase deficiency, ornithine transcarbamylase deficiency, molybdenum cofactor deficiency, adenylosuccinase deficiency, or dihydroPyrimidine dehydrogenase deficiency. Conclusions: HPLC-ESI MS/MS of urine allows rapid screening for disorders of purine and Pyrimidine Metabolism. The filter paper strips offer the advantage of easy collection, transport, and storage of the urine samples.
R. A. De Abreu - One of the best experts on this subject based on the ideXlab platform.
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purine and Pyrimidine Metabolism and electrocortical brain activity during hypotension in near term lambs
Neonatology, 2006Co-Authors: Sandra Van Os, R. A. De Abreu, J C W Hopman, Karina Wethly, Margot Van De BorAbstract:Background: Insufficient cerebral O2 supply leads to cellular energy failure and loss of brain cell function. The relationship between the severity of cellular energy failure due to hemorrhagic hypotension and the loss of electrocortical brain activity (ECBA), as a measure of brain cell function, is not yet fully elucidated in near-term born lambs. Objectives: To study the relationship between cerebral purine and Pyrimidine Metabolism, as a measure of brain cell energy failure, and brain cell function after hemorrhagic hypotension in near-term born lambs. Methods: Eight near-term lambs (term 147 days) were delivered at 131 days of gestation. After a stabilization period, mean arterial blood pressure was reduced till 30% of baseline by withdrawal of blood. Cerebrospinal fluid (CSF) was obtained at the end of the hypotensive period (2.5 h). CSF from 8 siblings was used for comparison. HPLC was used to determine purine and Pyrimidine metabolites in CSF, as a measure of cellular energy failure. ECBA was calculated as the root mean square value of a band-filtered (2–16 Hz) one-channel EEG. Results: Values of guanosine, inosine, hypoxanthine, xanthine and uridine were significantly higher, while ECBA was significantly lower after hemorrhagic hypotension than control values. The concentrations of inosine, hypoxanthine, xanthine and uridine were significantly negatively linearly related to ECBA. Conclusions: Brain cell function is negatively related to concentrations of inosine, hypoxanthine, xanthine and uridine in the CSF after hemorrhagic hypotension in near-term born lambs.
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1H-NMR Spectroscopy of Body Fluids: Inborn Errors of Purine and Pyrimidine Metabolism
Clinical Chemistry, 1999Co-Authors: Sytske H. Moolenaar, J.g.n. De Jong, Christa Bräutigam, Ries Duran, R. A. De AbreuAbstract:Background: The diagnosis of inborn errors of purine and Pyrimidine Metabolism is often difficult. We examined the potential of 1H-NMR as a tool in evaluation of patients with these disorders. Methods: We performed 1H-NMR spectroscopy on 500 and 600 MHz instruments with a standardized sample volume of 500 μL. We studied body fluids from 25 patients with nine inborn errors of purine and Pyrimidine Metabolism. Results: Characteristic abnormalities could be demonstrated in the 1H-NMR spectra of urine samples of all patients with diseases in the Pyrimidine Metabolism. In most urine samples from patients with defects in the purine Metabolism, the 1H-NMR spectrum pointed to the specific diagnosis in a straightforward manner. The only exception was a urine from a case of adenine phosphoribosyl transferase deficiency in which the accumulating metabolite, 2,8-dihydroxyadenine, was not seen under the operating conditions used. Similarly, uric acid was not measured. We provide the 1H-NMR spectral characteristics of many intermediates in purine and Pyrimidine Metabolism that may be relevant for future studies in this field. Conclusion: The overview of Metabolism that is provided by 1H-NMR spectroscopy makes the technique a valuable screening tool in the detection of inborn errors of purine and Pyrimidine Metabolism.
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1H NMR spectroscopy of body fluids in patients with inborn errors of purine and Pyrimidine Metabolism
Journal of Inherited Metabolic Disease, 1997Co-Authors: Ron A Wevers, Arend Heerschap, Udo F H Engelke, Jan J. Rotteveel, J.g.n. De Jong, R. A. De AbreuAbstract:1H NMR spectroscopy of body fluids has been used in the diagnosis of many inborn errors of Metabolism (Lehnert and Hunkler 1986; Iles and Chalmers 1988). To our knowledge there is no systematic study available of body fluids from patients with inborn errors in the purine or Pyrimidine Metabolism. The main advantage of the technique over others that are used diagnostically in the screening for inborn errors of Metabolism is the minimal sample pretreatment required for NMR spectroscopy. Fractionation, extraction or derivatization of metabolites is not required. A further advantage is the overall view of proton-containing metabolites. Quantification of metabolites is possible. An obvious disadvantage is the substantial cost of high-field NMR spectrometers that are required for this work. This paper demonstrates that NMR spectroscopy can be used in diagnosing inborn errors in purine and Pyrimidine Metabolism. Examples are given of NMR spectra of body fluids from patients with dihydroPyrimidine dehydrogenase deficiency (McKusick 274270) and with dihydropyrimidinase deficiency (McKusick 222748).
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molecular genetics biochemistry and clinical aspects of inherited disorders of purine and Pyrimidine Metabolism
1993Co-Authors: Ursula Gresser, R. A. De AbreuAbstract:I Purine Salvage Enzymes.- IA Hypoxanthine Guanine Phosphoribosyltransferase (HGPRT) Deficiency 3.- 1 Introductory Remarks.- 2 The Clinical Aspects of HGPRT Deficiency.- 3 The Biochemical Basis of HGPRT Deficiency.- 4 Prenatal Diagnosis of Lesch-Nyhan Syndrome.- 5 The Genetic Basis of HGPRT Deficiency.- IB Adenine Phosphoribosyltransferase (APRT) Deficiency 41.- 1 The Clinical Aspects of APRT Deficiency.- 2 The Biochemical Basis of APRT Deficiency.- 3 The Genetic Basis of APRT Deficiency.- II Hyperuricemia and Gout Caused by a Defect in Renal Transport.- 1 The Clinical Aspects of Hyperuricemia and Gout.- 2 The Biochemical Basis of Hyperuricemia and Gout.- 3 The Genetic Basis of Hyperuricemia and Gout.- III Immunodeficiency Disease: Adenosine Deaminase (ADA) and Purine-Nucleoside Phosphorylase (PNP) Deficiencies.- 1 Introductory Remarks.- 2 The Clinical Aspects of ADA and PNP Deficiencies.- 3 The Biochemical Basis and Pathophysiology of ADA and PNP Deficiencies.- 4 The Genetic and Metabolic Basis of ADA Deficiency.- IV The Purine Nucleotide Cycle.- IVA Myoadenylate (Muscle AMP) Deaminase Deficiency 115.- 1 Clinical Aspects and Biochemical Basis of AMP Deaminase Deficiency: A Clinician's Point of View.- 2 The AMP Deaminase Multigene Family in Rats and Humans.- 3 The Genetic Basis of Myoadenylate Deaminase Deficiency in Man.- IVB Adenylosuccinate Lyase (ASase) Deficiency 140.- 1 The Clinical Aspects of ASase Deficiency.- 2 The Biochemical Aspects of ASase Deficiency.- 3 The Genetic Basis of ASase Deficiency.- V Pyrimidine Metabolism.- 1 Dihydropyrimidinuria Presenting in Childhood with Severe Developmental Retardation.- 2 The Clinical Aspects of Inherited Defects in Pyrimidine Degradation.- 3 DihydroPyrimidine Dehydrogenase Deficiency: Biochemical and Genetic Basis.
Andre B P Van Kuilenburg - One of the best experts on this subject based on the ideXlab platform.
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the application of hplc esi tandem mass spectrometry on urine soaked filter paper strips for the screening of disorders of purine and Pyrimidine Metabolism
Journal of Inherited Metabolic Disease, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Inherited disorders of purine and Pyrimidine Metabolism have a wide variety of clinical presentations that are often non-specific, and severity of individual cases ranges from fatal to asymptomatic. Because of this broad clinical spectrum, a simple, rapid and specific screening method is desired for the diagnosis of these disorders. Several high-performance liquid chromatography (HPLC) methods for screening for these disorders have been reported (Duran et al 1997; Sumi et al 1995), but so far these methods are time-consuming and non-specific. Connection of HPLC with tandem mass spectrometry (MS/MS) has the advantage of rapidity and specificity. We describe an analytical method for routinely screening disorders of purine and Pyrimidine Metabolism on urine-soaked filter-paper strips using reversed-phase HPLC coupled with electrospray ionization (ESI) MS/MS. This method enables easy sample collection, even from the patient's home, mailing and storage (Blau et al 1998; McCann et al 1995).
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rapid screening of high risk patients for disorders of purine and Pyrimidine Metabolism using hplc electrospray tandem mass spectrometry of liquid urine or urine soaked filter paper strips
Clinical Chemistry, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Background: A rapid and specific screening method for patients at risk of inherited disorders of purine and Pyrimidine Metabolism is desirable because symptoms are varied and nonspecific. The aim of this study was to develop a rapid and specific method for screening with use of liquid urine samples or urine-soaked filter paper strips. Methods: Reverse-phase HPLC was combined with electrospray ionization (ESI), tandem mass spectrometry (MS/MS), and detection performed by multiple reaction monitoring. Transitions and instrument settings were established for 17 purines or Pyrimidines. Stable-isotope-labeled reference compounds were used as internal standards when available. Results: Total analysis time of this method was 15 min, approximately one-third that of conventional HPLC with ultraviolet detection. Recoveries were 96–107% in urine with added analyte, with two exceptions (hypoxanthine, 64%; xanthine, 79%), and 89–110% in urine-soaked filter paper strips, with three exceptions (hypoxanthine, 65%; xanthine, 77%; 5-hydroxymethyluracil, 80%). The expected abnormalities were easily found in samples from patients with purine nucleoside phosphorylase deficiency, ornithine transcarbamylase deficiency, molybdenum cofactor deficiency, adenylosuccinase deficiency, or dihydroPyrimidine dehydrogenase deficiency. Conclusions: HPLC-ESI MS/MS of urine allows rapid screening for disorders of purine and Pyrimidine Metabolism. The filter paper strips offer the advantage of easy collection, transport, and storage of the urine samples.
Arno Van Cruchten - One of the best experts on this subject based on the ideXlab platform.
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the application of hplc esi tandem mass spectrometry on urine soaked filter paper strips for the screening of disorders of purine and Pyrimidine Metabolism
Journal of Inherited Metabolic Disease, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Inherited disorders of purine and Pyrimidine Metabolism have a wide variety of clinical presentations that are often non-specific, and severity of individual cases ranges from fatal to asymptomatic. Because of this broad clinical spectrum, a simple, rapid and specific screening method is desired for the diagnosis of these disorders. Several high-performance liquid chromatography (HPLC) methods for screening for these disorders have been reported (Duran et al 1997; Sumi et al 1995), but so far these methods are time-consuming and non-specific. Connection of HPLC with tandem mass spectrometry (MS/MS) has the advantage of rapidity and specificity. We describe an analytical method for routinely screening disorders of purine and Pyrimidine Metabolism on urine-soaked filter-paper strips using reversed-phase HPLC coupled with electrospray ionization (ESI) MS/MS. This method enables easy sample collection, even from the patient's home, mailing and storage (Blau et al 1998; McCann et al 1995).
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rapid screening of high risk patients for disorders of purine and Pyrimidine Metabolism using hplc electrospray tandem mass spectrometry of liquid urine or urine soaked filter paper strips
Clinical Chemistry, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Background: A rapid and specific screening method for patients at risk of inherited disorders of purine and Pyrimidine Metabolism is desirable because symptoms are varied and nonspecific. The aim of this study was to develop a rapid and specific method for screening with use of liquid urine samples or urine-soaked filter paper strips. Methods: Reverse-phase HPLC was combined with electrospray ionization (ESI), tandem mass spectrometry (MS/MS), and detection performed by multiple reaction monitoring. Transitions and instrument settings were established for 17 purines or Pyrimidines. Stable-isotope-labeled reference compounds were used as internal standards when available. Results: Total analysis time of this method was 15 min, approximately one-third that of conventional HPLC with ultraviolet detection. Recoveries were 96–107% in urine with added analyte, with two exceptions (hypoxanthine, 64%; xanthine, 79%), and 89–110% in urine-soaked filter paper strips, with three exceptions (hypoxanthine, 65%; xanthine, 77%; 5-hydroxymethyluracil, 80%). The expected abnormalities were easily found in samples from patients with purine nucleoside phosphorylase deficiency, ornithine transcarbamylase deficiency, molybdenum cofactor deficiency, adenylosuccinase deficiency, or dihydroPyrimidine dehydrogenase deficiency. Conclusions: HPLC-ESI MS/MS of urine allows rapid screening for disorders of purine and Pyrimidine Metabolism. The filter paper strips offer the advantage of easy collection, transport, and storage of the urine samples.
Albert H Bootsma - One of the best experts on this subject based on the ideXlab platform.
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the application of hplc esi tandem mass spectrometry on urine soaked filter paper strips for the screening of disorders of purine and Pyrimidine Metabolism
Journal of Inherited Metabolic Disease, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Inherited disorders of purine and Pyrimidine Metabolism have a wide variety of clinical presentations that are often non-specific, and severity of individual cases ranges from fatal to asymptomatic. Because of this broad clinical spectrum, a simple, rapid and specific screening method is desired for the diagnosis of these disorders. Several high-performance liquid chromatography (HPLC) methods for screening for these disorders have been reported (Duran et al 1997; Sumi et al 1995), but so far these methods are time-consuming and non-specific. Connection of HPLC with tandem mass spectrometry (MS/MS) has the advantage of rapidity and specificity. We describe an analytical method for routinely screening disorders of purine and Pyrimidine Metabolism on urine-soaked filter-paper strips using reversed-phase HPLC coupled with electrospray ionization (ESI) MS/MS. This method enables easy sample collection, even from the patient's home, mailing and storage (Blau et al 1998; McCann et al 1995).
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rapid screening of high risk patients for disorders of purine and Pyrimidine Metabolism using hplc electrospray tandem mass spectrometry of liquid urine or urine soaked filter paper strips
Clinical Chemistry, 2000Co-Authors: Andre B P Van Kuilenburg, Albert H Bootsma, Anja J Haasnoot, Arno Van Cruchten, Yoshiro Wada, Alberth H. Van GennipAbstract:Background: A rapid and specific screening method for patients at risk of inherited disorders of purine and Pyrimidine Metabolism is desirable because symptoms are varied and nonspecific. The aim of this study was to develop a rapid and specific method for screening with use of liquid urine samples or urine-soaked filter paper strips. Methods: Reverse-phase HPLC was combined with electrospray ionization (ESI), tandem mass spectrometry (MS/MS), and detection performed by multiple reaction monitoring. Transitions and instrument settings were established for 17 purines or Pyrimidines. Stable-isotope-labeled reference compounds were used as internal standards when available. Results: Total analysis time of this method was 15 min, approximately one-third that of conventional HPLC with ultraviolet detection. Recoveries were 96–107% in urine with added analyte, with two exceptions (hypoxanthine, 64%; xanthine, 79%), and 89–110% in urine-soaked filter paper strips, with three exceptions (hypoxanthine, 65%; xanthine, 77%; 5-hydroxymethyluracil, 80%). The expected abnormalities were easily found in samples from patients with purine nucleoside phosphorylase deficiency, ornithine transcarbamylase deficiency, molybdenum cofactor deficiency, adenylosuccinase deficiency, or dihydroPyrimidine dehydrogenase deficiency. Conclusions: HPLC-ESI MS/MS of urine allows rapid screening for disorders of purine and Pyrimidine Metabolism. The filter paper strips offer the advantage of easy collection, transport, and storage of the urine samples.
