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Puusepp S, Reinson K, Pajusalu S, van Kuilenburg ABP, Dobritzsch D, Roelofsen J, Stenzel W, Õunap K. Atypical presentation of Arts syndrome due to a novel hemizygous loss-of-function variant in the PRPS1 gene. Mol Genet Metab Rep 2020; 25:100677. [PMID: 33294372 PMCID: PMC7689168 DOI: 10.1016/j.ymgmr.2020.100677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/06/2020] [Accepted: 11/07/2020] [Indexed: 11/30/2022] Open
Abstract
The PRPS1 gene, located on Xq22.3, encodes phosphoribosyl-pyrophosphate synthetase (PRPS), a key enzyme in de novo purine synthesis. Three clinical phenotypes are associated with loss-of-function PRPS1 variants and decreased PRPS activity: Arts syndrome (OMIM: 301835), Charcot–Marie–Tooth disease type 5 (CMTX5, OMIM: 311070), and nonsyndromic X-linked deafness (DFN2, OMIM: 304500). Hearing loss is present in all cases. CMTX5 patients also show peripheral neuropathy and optic atrophy. Arts syndrome includes developmental delay, intellectual disability, ataxia, and susceptibility to infections, in addition to the above three features. Gain-of-function PRPS1 variants result in PRPS superactivity (OMIM: 300661) with hyperuricemia and gout. We report a 6-year-old boy who presented with marked generalized muscular hypotonia, global developmental delay, lack of speech, trunk instability, exercise intolerance, hypomimic face with open mouth, oropharyngeal dysphagia, dysarthria, and frequent upper respiratory tract infections. However, his nerve conduction velocity, audiologic, and funduscopic investigations were normal. A novel hemizygous variant, c.130A > G p.(Ile44Val), was found in the PRPS1 gene by panel sequencing. PRPS activity in erythrocytes was markedly reduced, confirming the pathogenicity of the variant. Serum uric acid and urinary purine and pyrimidine metabolite levels were normal. In conclusion, we present a novel PRPS1 loss-of-function variant in a patient with some clinical features of Arts syndrome, but lacking a major attribute, hearing loss, which is congenital/early-onset in all other reported Arts syndrome patients. In addition, it is important to acknowledge that normal levels of serum and urinary purine and pyrimidine metabolites do not exclude PRPS1-related disorders. We describe a male patient with atypical presentation of Arts syndrome. Our patient harbors a novel loss-of-function variant in the PRPS1 gene. The purine and pyrimidine levels can be normal in patients with decreased PRPS activity.
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Affiliation(s)
- Sanna Puusepp
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Karit Reinson
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia.,Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - André B P van Kuilenburg
- Department of Clinical Chemistry, Cancer Center Amsterdam, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Jeroen Roelofsen
- Department of Clinical Chemistry, Cancer Center Amsterdam, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Werner Stenzel
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Leibniz Science Campus Chronic Inflammation, Berlin, Germany
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
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Pseudouridylation defect due to DKC1 and NOP10 mutations causes nephrotic syndrome with cataracts, hearing impairment, and enterocolitis. Proc Natl Acad Sci U S A 2020; 117:15137-15147. [PMID: 32554502 DOI: 10.1073/pnas.2002328117] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
RNA modifications play a fundamental role in cellular function. Pseudouridylation, the most abundant RNA modification, is catalyzed by the H/ACA small ribonucleoprotein (snoRNP) complex that shares four core proteins, dyskerin (DKC1), NOP10, NHP2, and GAR1. Mutations in DKC1, NOP10, or NHP2 cause dyskeratosis congenita (DC), a disorder characterized by telomere attrition. Here, we report a phenotype comprising nephrotic syndrome, cataracts, sensorineural deafness, enterocolitis, and early lethality in two pedigrees: males with DKC1 p.Glu206Lys and two children with homozygous NOP10 p.Thr16Met. Females with heterozygous DKC1 p.Glu206Lys developed cataracts and sensorineural deafness, but nephrotic syndrome in only one case of skewed X-inactivation. We found telomere attrition in both pedigrees, but no mucocutaneous abnormalities suggestive of DC. Both mutations fall at the dyskerin-NOP10 binding interface in a region distinct from those implicated in DC, impair the dyskerin-NOP10 interaction, and disrupt the catalytic pseudouridylation site. Accordingly, we found reduced pseudouridine levels in the ribosomal RNA (rRNA) of the patients. Zebrafish dkc1 mutants recapitulate the human phenotype and show reduced 18S pseudouridylation, ribosomal dysregulation, and a cell-cycle defect in the absence of telomere attrition. We therefore propose that this human disorder is the consequence of defective snoRNP pseudouridylation and ribosomal dysfunction.
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Monostori P, Klinke G, Hauke J, Richter S, Bierau J, Garbade SF, Hoffmann GF, Langhans CD, Haas D, Okun JG. Extended diagnosis of purine and pyrimidine disorders from urine: LC MS/MS assay development and clinical validation. PLoS One 2019; 14:e0212458. [PMID: 30817767 PMCID: PMC6394934 DOI: 10.1371/journal.pone.0212458] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/01/2019] [Indexed: 12/31/2022] Open
Abstract
Background and aims Inborn errors of purine and pyrimidine metabolism are a diverse group of disorders with possible serious or life-threatening symptoms. They may be associated with neurological symptoms, renal stone disease or immunodeficiency. However, the clinical presentation can be nonspecific and mild so that a number of cases may be missed. Previously published assays lacked detection of certain diagnostically important biomarkers, including SAICAr, AICAr, beta-ureidoisobutyric acid, 2,8-dihydroxyadenine and orotidine, necessitating the use of separate assays for their detection. Moreover, the limited sensitivity for some analytes in earlier assays may have hampered the reliable detection of mild cases. Therefore, we aimed to develop a liquid chromatography–tandem mass spectrometry (LC-MS/MS) assay that allows the simultaneous and sensitive detection of an extended range of purine and pyrimidine biomarkers in urine. Methods The assay was developed and validated using LC-MS/MS and clinically tested by analyzing ERNDIM Diagnostic Proficiency Testing (DPT) samples and further specimens from patients with various purine and pyrimidine disorders. Results Reliable determination of 27 analytes including SAICAr, AICAr, beta-ureidoisobutyric acid, 2,8-dihydroxyadenine and orotidine was achieved in urine following a simple sample preparation. The method clearly distinguished pathological and normal samples and differentiated between purine and pyrimidine defects in all clinical specimens. Conclusions A LC-MS/MS assay allowing the simultaneous, sensitive and reliable diagnosis of an extended range of purine and pyrimidine disorders has been developed. The validated method has successfully been tested using ERNDIM Diagnostic Proficiency Testing (DPT) samples and further clinical specimens from patients with various purine and pyrimidine disorders. Sample preparation is simple and assay duration is short, facilitating an easier inclusion of the assay into the diagnostic procedures.
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Affiliation(s)
- Péter Monostori
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
- * E-mail:
| | - Glynis Klinke
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Jana Hauke
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Sylvia Richter
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Jörgen Bierau
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Sven F. Garbade
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Georg F. Hoffmann
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Claus-Dieter Langhans
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Dorothea Haas
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Jürgen G. Okun
- Department of General Pediatrics, Division of Neuropediatrics and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
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Porosk R, Terasmaa A, Mahlapuu R, Soomets U, Kilk K. Metabolomics of the Wolfram Syndrome 1 Gene (Wfs1) Deficient Mice. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2018; 21:721-732. [PMID: 29257731 DOI: 10.1089/omi.2017.0143] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Wolfram syndrome 1 is a rare autosomal recessive neurodegenerative disease characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness. Mutations in the WFS1 gene encoding the wolframin glycoprotein can lead to endoplasmic reticulum stress and unfolded protein responses in cells, but the pathophysiology at whole organism level is poorly understood. In this study, several organs (heart, liver, kidneys, and pancreas) and bodily fluids (trunk blood and urine) of 2- and 6-month old Wfs1 knockout (KO), heterozygote (HZ), and wild-type (WT) mice were analyzed by untargeted and targeted metabolomics using liquid chromatography-mass spectrometry. The key findings were significant perturbations in the metabolism of pancreas and heart before the onset of related clinical signs such as glycosuria that precedes hyperglycemia and thus implies a kidney dysfunction before the onset of classical diabetic nephropathy. The glucose use and gluconeogenesis in KO mice are intensified in early stages, but later the energetic needs are mainly covered by lipolysis. Furthermore, in young mice liver and trunk blood hypouricemia, which in time turns to hyperuricemia, was detected. In summary, we show that the metabolism in Wfs1-deficient mice markedly differs from the metabolism of WT mice in many aspects and discuss the future biological and clinical relevance of these observations.
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Affiliation(s)
- Rando Porosk
- 1 Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu , Tartu, Estonia
| | - Anton Terasmaa
- 2 Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu , Tartu, Estonia
| | - Riina Mahlapuu
- 1 Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu , Tartu, Estonia
| | - Ursel Soomets
- 1 Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu , Tartu, Estonia
| | - Kalle Kilk
- 1 Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu , Tartu, Estonia
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Rajasekeran H, Lytvyn Y, Bozovic A, Lovshin JA, Diamandis E, Cattran D, Husain M, Perkins BA, Advani A, Reich HN, Kulasingam V, Cherney DZI. Urinary adenosine excretion in type 1 diabetes. Am J Physiol Renal Physiol 2017; 313:F184-F191. [DOI: 10.1152/ajprenal.00043.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/30/2017] [Accepted: 04/03/2017] [Indexed: 11/22/2022] Open
Abstract
In experimental models of diabetes, augmented sodium-glucose cotransport-2 (SGLT2) activity diminishes sodium (Na+) delivery at the macula densa. As a result, less vasoconstrictive adenosine is generated, leading to afferent arteriolar vasodilatation and hyperfiltration. The measurement and significance of urinary adenosine in humans has not been examined extensively in states of renal hemodynamic impairment like that of diabetes. Our aim was to validate a method for urine adenosine quantification in humans and perform an exploratory post hoc analysis to determine whether urinary adenosine levels change dynamically in response to natriuresis in patients with type 1 diabetes (T1D) before and after treatment with the SGLT2 inhibitor (SGLT2i) empagliflozin. We hypothesized that SGLT2i, which reduces renal hyperfiltration through increased Na+delivery to the macula densa, would increase urinary adenosine excretion. Urine adenosine corrected for creatinine was measured using our validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method in 40 healthy participants and 40 patients with T1D. In the T1D cohort, measurements were performed during clamped euglycemic and hyperglycemic conditions before and following 8 wk of SGLT2i therapy. Urinary adenosine was detectable in healthy subjects (0.32 ± 0.11 µmol/mmol Cr) and patients with T1D. In response to SGLT2i, urine adenosine increased during clamped hyperglycemia (0.40 ± 0.11 vs. 0.45 ± 0.12 µmol/mmol Cr, P = 0.005). Similar trends were observed during clamped euglycemia ( P = 0.08). In conclusion, SGLT2i increases urinary adenosine excretion under clamped hyperglycemic conditions in patients with T1D. The potentially protective role of SGLT2i against glomerular hyperfiltration and its mediation by adenosine in diabetes merits further study.
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Affiliation(s)
- Harindra Rajasekeran
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Onatario, Canada
| | - Yuliya Lytvyn
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Andrea Bozovic
- Departments of Clinical Biochemistry and Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Julie A. Lovshin
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Eleftherios Diamandis
- Departments of Clinical Biochemistry and Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Daniel Cattran
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Mansoor Husain
- Division of Cardiology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada; and
| | - Bruce A. Perkins
- Division of Endocrinology and Metabolism, Department of Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Andrew Advani
- Division of Endocrinology, Department of Medicine, Saint Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Heather N. Reich
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Vathany Kulasingam
- Departments of Clinical Biochemistry and Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - David Z. I. Cherney
- Division of Nephrology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Onatario, Canada
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Highly specific colorimetric detection of DNA oxidation biomarker using gold nanoparticle/triplex DNA conjugates. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2016; 12:2101-2105. [DOI: 10.1016/j.nano.2016.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 05/15/2016] [Accepted: 05/18/2016] [Indexed: 01/18/2023]
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Zikanova M, Krijt J, Skopova V, Krijt M, Baresova V, Kmoch S. Screening for adenylosuccinate lyase deficiency using tandem mass spectrometry analysis of succinylpurines in neonatal dried blood spots. Clin Biochem 2014; 48:2-7. [PMID: 25445730 DOI: 10.1016/j.clinbiochem.2014.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/14/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVES Stable isotope dilution coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the sensitive method for screening for various inherited metabolic disorders using dried blood spots (DBSs). We present a method for LC-MS/MS determination of succinyladenosine (SAdo) and succinylaminoimidazole carboxamide riboside (SAICAr), biomarkers for adenylosuccinate lyase deficiency (dADSL), in DBS. DESIGN AND METHODS SAICAr and SAdo were separated on a Symmetry-C18 column and detected using positive electrospray ionisation in selected reaction monitoring mode. The quantification was performed using the isotopically labelled internal standards SAdo-(13)C4 and SAICAr-(13)C4, which were prepared via ADSL-catalysed reactions of fumarate-(13)C4 with adenosine monophosphate and aminoimidazole carboxamide ribotide, respectively, and subsequent alkaline phosphatase-catalysed dephosphorylation of the resulting products. RESULTS The detection of SAICAr and SAdo in DBS was linear over the range of 0-25μmol/L. The respective intra-assay and inter-assay imprecision values were less than 10.7% and 15.2% for SAICAr and 4.7% and 5.7% for SAdo. The recoveries from DBS spiked with different concentrations of SAICAr and SAdo were between 94% and 117%. The concentrations of SAICAr and SAdo were higher in the archived DBS from dADSL patients (SAICAr, 0.03-4.7μmol/L; SAdo, 1.5-21.3μmol/L; n=5) compared to those of the control subjects (SAICAr, 0-0.026μmol/L; SAdo, 0.06-0.14μmol/L; n=31), even after DBSs from dADSL patients were stored for 2-23years. CONCLUSIONS We developed and validated a method of succinylpurine analysis in DBS that improves selective screening for dADSL in the paediatric population and may be used for retrospective diagnosis to aid the genetic counselling of affected families.
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Affiliation(s)
- Marie Zikanova
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
| | - Jakub Krijt
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
| | - Vaclava Skopova
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
| | - Matyas Krijt
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
| | - Veronika Baresova
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
| | - Stanislav Kmoch
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 2, 128 08 Praha 2, Czech Republic.
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Szterk A, Roszko M. SIMULTANEOUS DETERMINATION OF FREE AMINO ACIDS, L-CARNOSINE, PURINE, PYRIMIDINE, AND NUCLEOSIDES IN MEAT BY LIQUID CHROMATOGRAPHY/SINGLE QUADRUPOLE MASS SPECTROMETRY. J LIQ CHROMATOGR R T 2014. [DOI: 10.1080/10826076.2012.758136] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Arkadiusz Szterk
- a Department of Functional Food and Commodities Faculty of Human Nutrition and Consumer Sciences , Warsaw University of Life Sciences , Warsaw , Poland
| | - Marek Roszko
- b Department of Food Analysis , Institute of Agricultural and Food Biotechnology , Warsaw , Poland
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The inclusion of ADA-SCID in expanded newborn screening by tandem mass spectrometry. J Pharm Biomed Anal 2014; 88:201-6. [DOI: 10.1016/j.jpba.2013.08.044] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 08/30/2013] [Accepted: 08/31/2013] [Indexed: 11/20/2022]
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Dragusha S, Shibata T, Yin S, Fujita JY, Kabashima T, Kai M. Selective, sensitive and fluorometric determination of urinary cytosine with 4-trifluoromethylbenzamidoxime and N,N-dimethylformamide. Clin Chim Acta 2013; 429:123-8. [PMID: 24296265 DOI: 10.1016/j.cca.2013.11.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 11/22/2013] [Accepted: 11/23/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND Cytosine in urine is one of the biomarkers for the diagnosis of metabolic immunodeficiency. It has been mentioned that a high level of cytosine is found in urine of children having immunodeficiency. In this study, we have developed a fluorescence (fluorescence) derivatization reaction of cytosine using 4-trifluoromethylbenzamidoxime (4-TFMBAO) as a fluorogenic reagent. METHODS In this reaction, cytosine was mixed with 4-TFMBAO, K3[Fe(CN)6], N,N-dimethylformamide (DMF) and KOH in an aqueous solution. The mixture was heated at 100°C for 20 min. The fluorescence intensity of the mixture was measured with a spectrofluorometer. RESULTS Under the optimized reaction conditions, a strong fluorescence was produced only from cytosine amongst 62 compounds including structurally related bio-substances. The selectivity and sensitivity of this method were compared with a conventional fluorescence one using 2-bromoacetophenone that reacts with cytosine, adenine and their related substances. The present method was sufficiently selective toward cytosine, and approximately 50 times more sensitive than the conventional one. CONCLUSIONS Our method permitted the quantitative determination of cytosine in human urines without any pretreatment for a primary screening test of inborn disorder in pyrimidine metabolism with immunodeficiency, and indicated the lower detection limit of 0.1 μmol/l cytosine which gave 3 times greater fluorescence intensity than that observed for the reagent blank.
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Affiliation(s)
- Shpend Dragusha
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan
| | - Takayuki Shibata
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan
| | - Sheng Yin
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan
| | - Jun-ya Fujita
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan
| | - Tsutomu Kabashima
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan
| | - Masaaki Kai
- Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan.
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la Marca G, Canessa C, Giocaliere E, Romano F, Duse M, Malvagia S, Lippi F, Funghini S, Bianchi L, Della Bona ML, Valleriani C, Ombrone D, Moriondo M, Villanelli F, Speckmann C, Adams S, Gaspar BH, Hershfield M, Santisteban I, Fairbanks L, Ragusa G, Resti M, de Martino M, Guerrini R, Azzari C. Tandem mass spectrometry, but not T-cell receptor excision circle analysis, identifies newborns with late-onset adenosine deaminase deficiency. J Allergy Clin Immunol 2013; 131:1604-10. [DOI: 10.1016/j.jaci.2012.08.054] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 01/01/2023]
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13
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Ni M, Duley J, George R, Charles B, Shannon C, McGeary R, Norris R. Simultaneous determination of thymine and its sequential catabolites dihydrothymine and β-ureidoisobutyrate in human plasma and urine using liquid chromatography–tandem mass spectrometry with pharmacokinetic application. J Pharm Biomed Anal 2013; 78-79:129-35. [DOI: 10.1016/j.jpba.2013.01.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 01/18/2013] [Accepted: 01/19/2013] [Indexed: 11/16/2022]
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Zhang Q, Wang Y, Meng X, Dhar R, Huang H. Triple-stranded DNA containing 8-oxo-7,8-dihydro-2'-deoxyguanosine: implication in the design of selective aptamer sensors for 8-oxo-7,8-dihydroguanine. Anal Chem 2012; 85:201-7. [PMID: 23237478 DOI: 10.1021/ac3033323] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
8-Oxo-7,8-dihydroguanine (8-oxoG, or OG) as a free base has been widely considered as a biomarker for DNA oxidative damage. Currently no fluorescence sensor has been developed to directly detect 8-oxoG less than 100 nM. In this study, two triple-stranded DNAs were selected as the scaffolds to rationally design DNA aptamer sensors for 8-oxoG. The cavity was created by deleting the 8-oxodG nucleoside in a triplex containing an A·OG-C triad or a C·OG-A triad. The results showed that the fluorescence of both sensors were completely quenched by 8-oxoG. The detection ranges of the two sensors were different, while the combined range was comparable to the detection range of an antibody-based method. This result is expected to enable a fast, low-cost, and reusable method to measure 8-oxoG concentration.
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Affiliation(s)
- Qian Zhang
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, 07102, United States
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Neubauer S, Rugova A, Chu DB, Drexler H, Ganner A, Sauer M, Mattanovich D, Hann S, Koellensperger G. Mass spectrometry based analysis of nucleotides, nucleosides, and nucleobases--application to feed supplements. Anal Bioanal Chem 2012; 404:799-808. [PMID: 22752403 DOI: 10.1007/s00216-012-6170-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 05/09/2012] [Accepted: 05/30/2012] [Indexed: 01/07/2023]
Abstract
In this work, accurate MS-based methods for quantitative profiling of nucleotides, nucleosides, and nucleobases in yeast extracts used as additives in animal feedstuff are presented. Reversed-phase chromatography utilizing a stationary phase compatible with 100% aqueous mobile phases resulted in superior analytical figures of merit than HILIC or ion-pair reversed-phase separation. The novel separation method was combined with both molecular and elemental mass spectrometry. By use of RP-LC-MS-MS, excellent limits of detection <1 μmol L(-1) could be obtained for all the compounds investigated. The elemental speciation analysis approach enabled determination of nucleotides by phosphorus detection. Sensitivity of LC-ICP-MS was 1-2 orders of magnitude lower than that of LC-MS-MS. Quantitative analysis of yeast products using complementary MS detection furnished values in good agreement.
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Affiliation(s)
- Stefan Neubauer
- Department of Chemistry, Division of Analytical Chemistry, University of Natural Resources and Life Sciences-BOKU, Vienna, Austria
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Neonatal screening for severe combined immunodeficiency caused by an adenosine deaminase defect: a reliable and inexpensive method using tandem mass spectrometry. J Allergy Clin Immunol 2011; 127:1394-9. [PMID: 21624616 DOI: 10.1016/j.jaci.2011.03.040] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 02/18/2011] [Accepted: 03/24/2011] [Indexed: 12/19/2022]
Abstract
BACKGROUND Adenosine deaminase (ADA)-severe combined immunodeficiency (SCID) is an SCID caused by a defect in the enzyme adenosine deaminase. It is usually fatal in infancy because of severe recurrent infections. When diagnosis is made, permanent damage caused by infections or by metabolites is often present. Gene therapy, bone marrow transplantation, or enzyme therapy might be effective if performed early. ADA-SCID complies with all the criteria for inclusion in a newborn screening program. However, screening methods are still expensive or provide a non-negligible number of indeterminate results. OBJECTIVE The aim of the present study was to develop a simple, reliable, and inexpensive method for diagnosis of ADA-SCID by using dried blood spot (DBS) samples taken at birth. Cost per test was calculated, including the cost for reagents, equipment, and operators. METHODS DBS samples from 4 patients with genetically confirmed ADA-SCID and 12,020 DBS samples from healthy newborns were examined. Adenosine and 2'-deoxyadenosine were tested by using tandem mass spectrometry (PCT EP2010/070517). RESULTS The mean levels of adenosine and 2'-deoxyadenosine were 7.8 ± 3.1 and 8.5 ± 6.0 μmol/L, respectively, in affected children; adenosine was found at 0.23 ± 0.09 μmol/L, whereas 2'-deoxyadenosine was never detected in healthy control subjects (adenosine: P < 10(-6) [95% confidence limit, 7.59-7.78] and 2'-deoxyadenosine: P < 10(-6) [95% confidence limit, 8.65-8.82] for control subjects vs patients with ADA-SCID). No indeterminate or false-positive results were found. Cost per test was €0.01 ($0.013). A pilot population-based newborn screening for ADA-SCID has started in Tuscany, Italy. CONCLUSION Tandem mass spectrometry can be used for diagnosis of one of the most frequent form of SCID at a negligible cost.
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Shi J, Liu HF, Wong JM, Huang RN, Jones E, Carlson TJ. Development of a robust and sensitive LC-MS/MS method for the determination of adenine in plasma of different species and its application to in vivo studies. J Pharm Biomed Anal 2011; 56:778-84. [PMID: 21840665 DOI: 10.1016/j.jpba.2011.07.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/19/2011] [Accepted: 07/20/2011] [Indexed: 11/19/2022]
Abstract
A simple, robust, and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the measurement of endogenous adenine in mouse, rat, cynomolgus monkey, and human plasma. A "surrogate analyte" strategy was adopted by employing [(13)C(U)]-adenine as the surrogate analyte. The plasma samples were processed by protein precipitation, and the extracted supernatant samples were subjected directly to LC-MS/MS analysis. The analysis was carried out in the negative ion detection mode using selected-reaction monitoring (SRM). The method achieved a lower limit of quantification (LLOQ) of 5.0nM with a signal-to-noise ratio of 10. The intra- and inter-day assay coefficients of variation (CV) were ≤6.67% in rat plasma, and the mean recoveries and matrix effects across species and at various concentrations ranged from 88.8% to 104.2% and 86.0% to 110.8%, respectively. Using this methodology, the endogenous concentration of adenine in plasma of four species was found to range from 8.7nM in human to 93.1nM in cynomolgus monkey plasma. The assay was further applied to both an adenine pharmacokinetic study and a pivotal pharmacodynamic study evaluating the plasma concentration of adenine after a dose of 5'-deoxy-5'-methylthioadenosine (MTA).
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Affiliation(s)
- Jianxia Shi
- Department of Pharmacokinetics and Drug Metabolism, Amgen Inc., 1120 Veterans Blvd., South San Francisco, CA 94080, United States.
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Simultaneous LC–UV–MS–MS Analysis of Nine Pivotal Metabolites in Human Serum: Application to Studies of Impaired Glucose Tolerance. Chromatographia 2011. [DOI: 10.1007/s10337-010-1833-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Lazzarino G, Amorini AM, Di Pietro V, Tavazzi B. HPLC analysis for the clinical-biochemical diagnosis of inborn errors of metabolism of purines and pyrimidines. Methods Mol Biol 2011; 708:99-117. [PMID: 21207285 DOI: 10.1007/978-1-61737-985-7_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The determination of purines and pyrimidines in biofluids is useful for the clinical-biochemical characterization of acute and chronic pathological states that induce transient or permanent alterations of metabolism. In particular, the diagnosis of several inborn errors of metabolism (IEMs) is accomplished by the analysis of circulating and excreted purines and pyrimidines. It is certainly advantageous to simultaneously determine the full purine and pyrimidine profile, as well as to quantify other compounds of relevance (e.g., organic acids, amino acids, sugars) in various metabolic hereditary diseases, in order to screen for a large number of IEMs using a reliable and sensitive analytical method characterized by mild to moderate costs. Toward this end, we have developed an ion-pairing HPLC method with diode array detection for the synchronous separation of several purines and pyrimidines. This method also allows the quantification of additional compounds such as N-acetylated amino acids and dicarboxylic acids, the concentrations of which are profoundly altered in different IEMs. The application of the method in the analysis of biological samples from patients with suspected purine and pyrimidine disorders is presented to illustrate its applicability for the clinical-biochemical diagnosis of IEM.
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Affiliation(s)
- Giuseppe Lazzarino
- Division of Biochemistry and Molecular Biology, Department of Chemical Sciences, University of Catania, Catania, Italy.
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Analysis of seven purines and pyrimidines in pork meat products by ultra high performance liquid chromatography–tandem mass spectrometry. J Chromatogr A 2010; 1217:4294-9. [DOI: 10.1016/j.chroma.2010.04.033] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 03/23/2010] [Accepted: 04/12/2010] [Indexed: 11/30/2022]
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Dudley E, Yousef M, Wang Y, Griffiths WJ. Targeted metabolomics and mass spectrometry. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2010; 80:45-83. [PMID: 21109217 DOI: 10.1016/b978-0-12-381264-3.00002-3] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
While a great emphasis has been placed on global metabolomic analysis in recent years, the application of metabolomic style analyses to specific subsets of compounds (targeted metabolomics) also has merits in addressing biological questions in a more hypothesis-driven manner. These analyses are designed to selectively extract information regarding a group of related metabolites from the complex mixture of biomolecules present in most metabolomic samples. Furthermore, targeted metabolomics can also be applied to metabolism within macromolecules, hence furthering the systems biology impact of the analysis. This chapter describes the difference between the global metabolomics approach and the undertaking of metabolomics in a targeted manner and describes the application of this type of analysis in a number of biologically and medically relevant fields.
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Affiliation(s)
- E Dudley
- Institute of Mass Spectrometry, Swansea University, United Kingdom
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Abstract
This chapter is intended to familiarize readers with the field of metabolomics and some of the algorithms, data analysis strategies, and computer programs used to analyze or interpret metabolomic data. Specifically, this chapter provides a brief overview of the experimental approaches and applications of metabolomics followed by a description of the spectral and statistical analysis tools for metabolomics. The chapter concludes with a discussion of the resources that can be used to interpret and analyze metabolomic data at a biological or clinical level. Emerging needs, challenges, and recent progress being made in these areas are also discussed.
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Affiliation(s)
- David S Wishart
- Departments of Computing Science and Biological Sciences, University of Alberta, Alberta, Canada
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Mautjana NA, Looi DW, Eyler JR, Brajter-Toth A. Sensitivity of positive ion mode electrospray ionization mass spectrometry (ESI MS) in the analysis of purine bases in ESI MS and on-line electrochemistry ESI MS (EC/ESI MS). Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2009.07.083] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kilk K, Mahlapuu R, Soomets U, Langel Ü. Analysis of in vitro toxicity of five cell-penetrating peptides by metabolic profiling. Toxicology 2009; 265:87-95. [DOI: 10.1016/j.tox.2009.09.016] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 09/21/2009] [Accepted: 09/22/2009] [Indexed: 01/27/2023]
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25
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Xia JF, Liang QL, Liang XP, Wang YM, Hu P, Li P, Luo GA. Ultraviolet and tandem mass spectrometry for simultaneous quantification of 21 pivotal metabolites in plasma from patients with diabetic nephropathy. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:1930-6. [DOI: 10.1016/j.jchromb.2009.05.047] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 05/14/2009] [Accepted: 05/20/2009] [Indexed: 11/26/2022]
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Amorini AM, Petzold A, Tavazzi B, Eikelenboom J, Keir G, Belli A, Giovannoni G, Di Pietro V, Polman C, D'Urso S, Vagnozzi R, Uitdehaag B, Lazzarino G. Increase of uric acid and purine compounds in biological fluids of multiple sclerosis patients. Clin Biochem 2009; 42:1001-6. [PMID: 19341721 DOI: 10.1016/j.clinbiochem.2009.03.020] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 03/12/2009] [Accepted: 03/19/2009] [Indexed: 01/01/2023]
Abstract
OBJECTIVES In this study, the concentrations of uric acid, purine profile and creatinine in samples of cerebrospinal fluid and serum of multiple sclerosis (MS) patients were measured by HPLC and compared with corresponding values recorded in patients without MS (cerebrospinal fluid) and healthy subjects (serum). DESIGN AND METHODS All samples were deproteinized with ultrafiltration (which ensures minimal sample manipulation and efficient protein removal) and then assayed for the synchronous HPLC separation of uric acid, hypoxanthine, xanthine, inosine, adenosine, guanosine and creatinine. RESULTS The values of all compounds assayed were significantly higher in both biological fluids of MS patients with respect to values measured in controls. In particular, serum hypoxanthine, xanthine, uric acid and sum of oxypurines were, respectively, 3.17, 3.11, 1.23 and 1.27-fold higher in these patients than corresponding values recorded in controls (p<0.001). CONCLUSIONS Differently from what previously reported, we here demonstrate that all purine compounds, including uric acid, are elevated in biological fluids of MS patients. Reinforced by the trend observed for creatinine, this corroborates the notion of sustained purine catabolism, possibly due to imbalance in ATP homeostasis, under these pathological conditions. These results cast doubt on the hypothesis that uric acid is depleted in MS because of increased oxidative stress, rather suggesting that this disease causes a generalized increase in purine catabolism. As observed in other pathological states, uric acid, purine compounds and creatinine, can be considered markers of metabolic energy imbalance rather than of reactive oxygen species, even in MS.
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Affiliation(s)
- Angela M Amorini
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome Sacro Cuore, Rome, Italy
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Mautjana N, Estes J, Eyler J, Brajter-Toth A. One-Electron Oxidation and Sensitivity of Uric Acid in On-Line Electrochemistry and in Electrospray Ionization Mass Spectrometry. ELECTROANAL 2008. [DOI: 10.1002/elan.200804346] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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28
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Kathiwala M, Affum AO, Perry J, Brajter-Toth A. Direct measurements of xanthine in 2000-fold diluted xanthinuric urine with a nanoporous carbon fiber sensor. Analyst 2008; 133:810-6. [PMID: 18493684 DOI: 10.1039/b718125f] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High selectivity and sensitivity is reported in the measurements of xanthine in urine by fast scan cyclic voltammetry (FSV) with a nanostructured carbon fiber sensor of 3.5 +/- 0.4 mum radius. Fabrication of the sensors for the measurements is described. Fabrication of the nanostructure at the carbon fiber sensor surface exposes surface pores. SEM images confirm the formation of the nanostructure. The results indicate that the nanostructure improves the sensitivity and limit of detection (LOD) in the measurements of xanthine and uric acid. The sensors allow rapid direct measurements of xanthine in 2000-fold diluted xanthinuric urine and of uric acid in 2000-fold diluted normal urine. The sensitivity and the LOD of xanthine is 0.40 +/- 0.02 nA microM(-1) (0.995) and 1 microM, respectively, and 0.99 +/- 0.01 nA microM(-1) (0.998) and 500 nM for uric acid. The concentration of xanthine in 2000-fold diluted xanthinuric urine is 1.6 +/- 0.2 muM from FSV and from HPLC. The concentration of xanthine and uric acid in urine can be determined by pre- or post-calibration of the sensor in buffer or by the method of standard addition.
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Affiliation(s)
- Mehjabin Kathiwala
- University of Florida, Department of Chemistry, Gainesville, FL 32611-7200, USA
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:127-38. [PMID: 17199253 PMCID: PMC7166443 DOI: 10.1002/jms.1070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In order to keep subscribers up‐to‐date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of mass spectrometry. Each bibliography is divided into 11 sections: 1 Books, Reviews & Symposia; 2 Instrumental Techniques & Methods; 3 Gas Phase Ion Chemistry; 4 Biology/Biochemistry: Amino Acids, Peptides & Proteins; Carbohydrates; Lipids; Nucleic Acids; 5 Pharmacology/Toxicology; 6 Natural Products; 7 Analysis of Organic Compounds; 8 Analysis of Inorganics/Organometallics; 9 Surface Analysis; 10 Environmental Analysis; 11 Elemental Analysis. Within each section, articles are listed in alphabetical order with respect to author (6 Weeks journals ‐ Search completed at 4th. Oct. 2006)
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