Blood insulin level biosensor for athletes / Biossensor para nível de insulina sanguíneo em atletas / Biosensor para el nivel de insulina en sangre de deportistas

ABSTRACT Introduction: The pancreas releases insulin to assist the human body in utilizing blood glucose. It regulates metabolism by promoting the absorption of glucose into the blood. Objective: This work aimed to create an electrochemical biosensor based on magnetic graphene nanomaterial to measure insulin levels in athletes' blood. Method: A magnetic graphene nanocomposite created by graphene oxide (GO) and Fe-Ni bimetallic oxides on a glassy carbon electrode was synthesized using the electrochemical deposition method (GCE). Results: The immediate electrical deposition of Fe-Ni bimetallic oxide nanoparticles with the spherical shape on the GO nanosheet without aggregations was validated by structural characterizations of Fe-Ni/GO/GCE using XRD and SEM. The electrochemical results for insulin determination showed good sensitivity and anti-interference capability. The applicability and accuracy of the proposed electrochemical sensor to detect insulin were explored by blood serum samples from sportsmen. Conclusion: The results assigned acceptable RSD values (3.31% to 4.30%) and confirmed the feasibility of the proposed sensor for detecting athletes' blood insulin. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: A insulina é liberada pelo pâncreas para auxiliar o corpo humano na utilização da glicose sanguínea. Ela regula o metabolismo, promovendo a absorção da glicose pelo sangue. Objetivo: O objetivo deste trabalho foi criar um biossensor eletroquímico baseado em nanomaterial de grafeno magnético para medir os níveis de insulina no sangue dos atletas. Método: Em um eletrodo de carbono vítreo, um nanocomposto magnético de grafeno criado por óxido de grafeno (GO) e óxidos bimetálicos de Fe-Ni foi sintetizado usando o método de deposição eletroquímica (GCE). Resultados: A deposição elétrica imediata de nanopartículas de óxido bimetal Fe-Ni com a forma esférica na nano folha GO sem agregações foi validada por caracterizações estruturais de Fe-Ni/GO/GCE utilizando XRD e SEM. Os resultados eletroquímicos para determinação da insulina demonstraram boa sensibilidade e capacidade anti-interferência. A aplicabilidade e precisão do sensor eletroquímico proposto para detectar insulina foram exploradas por amostras de soro sanguíneo dos esportistas. Conclusão: Os resultados designados para os valores aceitáveis de RSD (3,31% a 4,30%) confirmaram a viabilidade do sensor proposto para detecção de insulina sanguínea de atletas. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: El páncreas libera insulina para ayudar al cuerpo humano a utilizar la glucosa en sangre. Regula el metabolismo, favoreciendo la absorción de la glucosa por la sangre. Objetivo: El objetivo de este trabajo fue crear un biosensor electroquímico basado en un nanomaterial de grafeno magnético para medir los niveles de insulina en la sangre de los deportistas. Método: Sobre un electrodo de carbono vítreo, se sintetizó un nanocompuesto de grafeno magnético creado por óxido de grafeno (GO) y óxidos bimetálicos de Fe-Ni mediante el método de deposición electroquímica (GCE). Resultados: La deposición eléctrica inmediata de las nanopartículas de óxido bimetálico Fe-Ni con forma esférica sobre la nano plancha de GO sin agregaciones fue validada por las caracterizaciones estructurales de Fe-Ni/GO/GCE mediante XRD y SEM. Los resultados electroquímicos para la determinación de la insulina mostraron una buena sensibilidad y capacidad anti-interferencia. La aplicabilidad y la precisión del sensor electroquímico propuesto para detectar la insulina se exploraron con muestras de suero sanguíneo de deportistas. Conclusión: Los resultados asignados a valores aceptables de RSD (3,31% a 4,30%) confirmaron la viabilidad del sensor propuesto para detectar la insulina en sangre de los atletas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

The diagnostic value of circulating microRNAs for middle-aged (40-60-year-old) coronary artery disease patients.

OBJECTIVE: Circulating microRNAs have been recognized as promising biomarkers for various diseases. The present study aimed to explore the potential roles of circulating miR-149, miR-424 and miR-765 as non-invasive biomarkers for the diagnosis of coronary artery disease in middle-aged (40-60-year-old) patients. METHODS: Sixty-five stable coronary artery disease patients (49-57 years old), 30 unstable coronary artery disease patients (49-58 years old), and 32 non-coronary artery disease patients (49--57 years old) who were matched for age, sex, smoking habits, hypertension and diabetes were enrolled in this study. Total RNA was isolated from plasma with TRIzol reagent. Circulating miRNA levels were measured by quantitative real-time polymerase chain reaction. RESULTS: Circulating miR-149 levels were decreased 4.49-fold in stable coronary artery disease patients (1.18 ± 0.84) and 5.09-fold in unstable coronary artery disease patients (1.04 ± 0.65) compared with non-coronary artery disease patients (5.30 ± 2.57) (p<0.001). Circulating miR-424 levels were reduced 3.6-fold in stable coronary artery disease patients (1.18 ± 0.60) and 5-fold in unstable coronary artery disease patients (0.86 ± 0.54) compared with non-coronary artery disease patients (4.35 ± 2.20) (p<0.001). In contrast, circulating miR-765 levels were elevated 3.98-fold in stable coronary artery disease patients (6.09 ± 2.27) and 5.33-fold in unstable coronary artery disease patients (8.17 ± 2.77) compared with non-coronary artery disease patients (1.53 ± 0.99) (p<0.001). Receiver operating characteristic curve analysis revealed that the respective areas under the curve for circulating miR-149, miR-424 and miR-765 were 0.938, 0.919 and 0.968 in stable CAD patients and 0.951, 0.960 and 0.977 in unstable coronary artery disease patients compared with non-coronary artery disease patients. CONCLUSION: Our results suggest that circulating miR-149, miR-424 and miR-765 might be novel, non-invasive biomarkers for the diagnosis of coronary artery disease in middle-aged patients. However, future prospective trials in large patient cohorts are necessary before reaching a solid conclusion.

The diagnostic value of circulating microRNAs for middle-aged (40–60-year-old) coronary artery disease patients

OBJECTIVE: Circulating microRNAs have been recognized as promising biomarkers for various diseases. The present study aimed to explore the potential roles of circulating miR-149, miR-424 and miR-765 as non-invasive biomarkers for the diagnosis of coronary artery disease in middle-aged (40–60-year-old) patients. METHODS: Sixty-five stable coronary artery disease patients (49–57 years old), 30 unstable coronary artery disease patients (49–58 years old), and 32 non-coronary artery disease patients (49–-57 years old) who were matched for age, sex, smoking habits, hypertension and diabetes were enrolled in this study. Total RNA was isolated from plasma with TRIzol reagent. Circulating miRNA levels were measured by quantitative real-time polymerase chain reaction. RESULTS: Circulating miR-149 levels were decreased 4.49-fold in stable coronary artery disease patients (1.18 ± 0.84) and 5.09-fold in unstable coronary artery disease patients (1.04 ± 0.65) compared with non-coronary artery disease patients (5.30 ± 2.57) (p<0.001). Circulating miR-424 levels were reduced 3.6-fold in stable coronary artery disease patients (1.18 ± 0.60) and 5-fold in unstable coronary artery disease patients (0.86 ± 0.54) compared with non-coronary artery disease patients (4.35 ± 2.20) (p<0.001). In contrast, circulating miR-765 levels were elevated 3.98-fold in stable coronary artery disease patients (6.09 ± 2.27) and 5.33-fold in unstable coronary artery disease patients (8.17 ± 2.77) compared with non-coronary artery disease patients (1.53 ± 0.99) (p<0.001). Receiver operating characteristic curve analysis revealed that the respective areas under the curve for circulating miR-149, miR-424 and miR-765 were 0.938, 0.919 and 0.968 in stable CAD patients and 0.951, 0.960 and 0.977 in unstable coronary artery disease patients compared with non-coronary artery disease patients. CONCLUSION: Our results suggest that circulating miR-149, ...