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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Nutrients
December 2024
Laboratory of Genetics of Aging and Longevity, Kazan State Medical University, 420012 Kazan, Russia.
Background: The monocarboxylate transporter 1 (MCT1) plays a crucial role in regulating lactate and pyruvate transport across cell membranes, which is essential for energy metabolism during exercise. The A1470T (rs1049434) polymorphism has been suggested to influence lactate transport, with the T (major) allele associated with greater transport efficiency. This study aimed to investigate the effect of the polymorphism on lactate and potassium (K) concentrations in response to resistance exercise (RE) following caffeine (CAF) ingestion.
View Article and Find Full Text PDFNutrients
December 2024
Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
Intestinal aging is characterized by declining protein homeostasis via reduced proteasome activity, which are hallmarks of age-related diseases. Our previous study showed that caffeine intake improved intestinal integrity with age by reducing vitellogenin (VIT, yolk protein) in . In this study, we investigated the regulatory mechanisms by which caffeine intake improves intestinal integrity and reduces vitellogenin (VIT) production in aged .
View Article and Find Full Text PDFNutrients
December 2024
Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 07804, Republic of Korea.
: Sleep, a process physiologically vital for mental health, faces disruptions in various sleep disorders linked to metabolic and neurodegenerative risks. seed (Zizy) has long been recognized for its diverse pharmacological attributes, including analgesic, sedative, insomnia, and anxiety alleviation. : In this study, the sleep-prolonging effects of Zizy extract (100, 200 mg/kg), along with their characterizing compounds jujuboside A (JuA) (5, 10 mg/kg), were evaluated in a mouse model under a pentobarbital-induced sleep.
View Article and Find Full Text PDFMedicina (Kaunas)
December 2024
División de Medicina Molecular, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), Guadalajara 44340, Jalisco, Mexico.
: Uric acid (UA) and the markers of mineral bone metabolism and inflammation are commonly altered in patients with chronic kidney disease (CKD) and are associated with the risk of cardiovascular complications and death. Studies point to a link between high serum UA and mineral bone homeostasis and inflammation, but controversy remains. The aim of this study was to evaluate the relationship between UA levels and mineral bone metabolism and inflammation biomarkers in a sample of Mexican patients with CKD 3a-5.
View Article and Find Full Text PDFBiomolecules
November 2024
Ludwig Boltzmann Institute for Arthritis and Rehabilitation, 5760 Saalfelden, Austria.
Introduction: Type 2 diabetes mellitus (T2DM) comprises heterogeneous disorders, which have an increase in blood glucose concentrations in common. Metabolic syndrome (MetS) describes the simultaneous occurrence of several clinical symptoms that increase the risk of cardiovascular disease and T2DM, although T2DM itself is also considered a risk factor for developing MetS.
Objective: This study aimed to identify parameters related to rehabilitation success and relevant to MetS in T2DM patients.
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