RESUMEN
Adenine phosphoribosyltransferase (APRT) deficiency is a rare , hereditary disorder characterized by renal excretion of 2,8-dihydroxyadenine (DHA), leading to kidney stone formation and chronic kidney disease (CKD). Treatment with a xanthine oxidoreductase inhibitor, allopurinol or febuxostat, reduces urinary DHA excretion and slows the progression of CKD. The method currently used for therapeutic monitoring of APRT deficiency lacks specificity and thus, a more reliable measurement technique is needed. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry method for simultaneous quantification of DHA, adenine, allopurinol, oxypurinol and febuxostat in human plasma was optimized and validated. Plasma samples were prepared with protein precipitation using acetonitrile followed by evaporation. The chemometric approach design of experiments was implemented to optimize gradient steepness, amount of organic solvent, flow rate, column temperature, cone voltage, desolvation temperature and desolvation flow rate. Experimental screening was conducted using fractional factorial design with addition of complementary experiments at the axial points for optimization of peak area, peak resolution and peak width. The assay was validated according to the US Food and Drug Administration guidelines for bioanalytical method validation over the concentration range of 50 to 5000 ng/mL for DHA, allopurinol and febuxostat, 100 to 5000 ng/mL for adenine and 50 to 12,000 ng/mL for oxypurinol, with r2 ≥ 0.99. The analytical assay achieved acceptable performance of accuracy (-10.8 to 8.3 %) and precision (CV < 15 %). DHA, adenine, allopurinol, oxypurinol and febuxostat were stable in plasma samples after five freeze-thaw cycles at -80 °C and after storage at -80 °C for 12 months. The assay was evaluated for quantification of the five analytes in clinical plasma samples from six APRT deficiency patients and proved to be both efficient and accurate. The proposed assay will be valuable for guiding pharmacotherapy and thereby contribute to improved and more personalized care for patients with APRT deficiency.
Asunto(s)
Adenina Fosforribosiltransferasa/deficiencia , Adenina/análogos & derivados , Alopurinol , Errores Innatos del Metabolismo , Insuficiencia Renal Crónica , Urolitiasis , Humanos , Alopurinol/uso terapéutico , Oxipurinol , Febuxostat , Cromatografía Liquida , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida con Espectrometría de Masas , Adenina/metabolismo , Adenina Fosforribosiltransferasa/metabolismo , Insuficiencia Renal Crónica/tratamiento farmacológicoRESUMEN
Adenine phosphoribosyltransferase enzyme deficiency is a rare, autosomal recessive disorder. It is a disease limited to the renal system and usually presents with urolithiasis. Herein, we report a young female with dihydroxyadenine (DHA) crystal-induced nephropathy presenting with rapidly progressive renal failure. DHA crystals can be easily diagnosed by their pathognomic color and shape in urine and biopsy specimens. A high index of clinical suspicion helps in the early diagnosis of this potentially treatable renal disease.
Asunto(s)
Femenino , Humanos , Adenina Fosforribosiltransferasa , Biopsia , Diagnóstico Precoz , Insuficiencia Renal , UrolitiasisRESUMEN
<p><b>OBJECTIVE</b>To identify adenine phosphoribosyltransferases in Schistosoma japonicum and analyze their structural features.</p><p><b>METHODS</b>Based on the accessible transcriptome and proteomic data, the S. japonicum adenine phosphoribosyl transferases were identified using bioinformatics approaches including bi-directional homology comparison, domain search and phylogenetic analysis. Homology modeling was also performed to describe the structural features of the proteins.</p><p><b>RESULTS AND CONCLUSION</b>Two homologue sequences of adenine phosphoribosyltransferase were obtained from S. japonicum, and the EST abundance, physico-chemical properties and three-dimensional structures of them were also acquired.</p>
Asunto(s)
Animales , Adenina Fosforribosiltransferasa , Química , Genética , Biología Computacional , Métodos , Proteínas del Helminto , Química , Genética , Isoenzimas , Química , Genética , Modelos Moleculares , Filogenia , Conformación Proteica , Schistosoma japonicumRESUMEN
No disponible
Asunto(s)
Humanos , Medicina Tropical , Mundo Occidental , Virosis , Regulación Enzimológica de la Expresión Génica , Xantina Deshidrogenasa , Fenotipo , Enfermedades Parasitarias , Litiasis , Infecciones Bacterianas , Adenina Fosforribosiltransferasa , GenotipoRESUMEN
No disponible
Asunto(s)
Humanos , Medicina Tropical , Mundo Occidental , Virosis , Regulación Enzimológica de la Expresión Génica , Xantina Deshidrogenasa , Enfermedades Parasitarias , Fenotipo , Litiasis , Infecciones Bacterianas , Adenina Fosforribosiltransferasa , GenotipoRESUMEN
A cardiomiopatia hipertrófica é doença genética autossômica dominante em mais da metade dos casos. Foram descritas, até o momento, mais de 270 mutações em dez genes que codificam proteínas do sarcômero cardíaco. Para cada gene existem diversas mutações, cada qual com particularidades quanto a hipertrofia miocárdica, penetrância e prognóstico, principalmente em relação a morte súbita. Há evidência de que outro fatores genéticos têm papel na hipertrofia da cardiomiopatia hpertrófica, como o polimorfismo no gene da enzima conversora da angiotensina e em outros genes modificadores, ambos podendo influenciar o grau de hipertrofia e, eventualmente, a ocorrência de morte súbita. Neste artigo são descritas as mutações relatadas na literatura, assim como nossa experiência no Instituto do Coração, que é a primeira no Brasil nessa moléstia