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1.
Br J Radiol ; 94(1121): 20200493, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33861155

RESUMO

OBJECTIVE: This study aimed to investigate the diagnostic performance of minimally invasive arthroscopy for knee gout when comparing with joint ultrasonography and dual-energy computed tomography (DECT). METHODS: From January 2016 to December 2018, 121 inpatients with knee joint swelling and pain were prospectively enrolled, including 63 gout patients and 58 non-gout patients. All patients underwent pre-operative ultrasonography and DECT to evaluate knee joint monosodium urate (MSU) deposits, followed by minimally invasive arthroscopy. The gold-standard for gout diagnosis was defined as the detection of MSU crystals in the synovial fluid under polarizing microscopic or pathological analysis. RESULTS: The diagnostic results of ultrasonic double contour sign, hyperechogenic foci, MSU deposition (detected by DECT), MSU deposition (detected by arthroscopy) and MSU deposition in cartilage (detected by arthroscopy) were significantly associated with that of the gold-standard. Except for hyperechogenic foci, the other four indexes had high sensitivity and specificity (approximately or over 80%) and a large odds ratio (OR) (14.73 to 36.56), indicating good diagnostic performance. Detection of MSU deposition in cartilage by arthroscopy had a good diagnostic agreement with the ultrasonic double contour sign (κ = 0.711, p < 0.001). CONCLUSION: Joint ultrasonography, DECT, and minimally invasive arthroscopy had high sensitivity and specificity for the diagnosis of knee gouty arthritis. Minimally invasive arthroscopy was superior to joint ultrasonography and DECT, which can be a useful supplement for the diagnosis of gout. ADVANCES IN KNOWLEDGE: This is the first study comparing the diagnostic performance for knee gout among the joint ultrasonography, DECT, and minimally invasive arthroscopy.


Assuntos
Artrite Gotosa/diagnóstico por imagem , Artroscopia/métodos , Articulação do Joelho/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Ácido Úrico/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Sensibilidade e Especificidade , Líquido Sinovial/química
2.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668211

RESUMO

The electrochemical-based detection of uric acid (UA) is widely used for diagnostic purposes. However, various interfering species such as ascorbic acid, dopamine, and glucose can affect electrochemical signals, and hence there is an outstanding need to develop improved sensing platforms to detect UA with high selectivity. Herein, we report a pentagonal mediator-based non-enzymatic electrochemical biosensing platform to selectively measure UA in the presence of interfering species. The working electrode was fabricated by electrodepositing polymerized 1-vinylimidazole (PVI), which has an imidazole ligand, onto indium tin oxide (ITO), and then conjugating nickel ions to the PVI-coated ITO electrode. Electrode performance was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements and integrated together with pentacyanoammineferrate, which can bind to the amine groups of UA and function as an electron transferring mediator. The experimental results showed a wide linear range of UA concentration-dependent responses and the multi-potential step (MPS) technique facilitated selective detection of UA in the presence of physiologically relevant interfering species. Altogether, these findings support that pentacyanoammineferrate-based non-enzymatic electrodes are suitable biosensing platforms for the selective measurement of UA, and such approaches could potentially be extended to other bioanalytes as well.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Ferrocianetos/química , Ácido Úrico/análise , Eletrodos
3.
ACS Appl Mater Interfaces ; 13(3): 3576-3590, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33449630

RESUMO

The plasmonic properties of gold nanoparticles (AuNPs) are a promising tool to develop sensing alternatives to traditional, enzyme-catalyzed reactions. The need for sensing alternatives, especially in underdeveloped areas of the world, has given rise to the application of nonenzymatic sensing approaches paired with cellulosic substrates to biochemical analysis. Herein, we present three individual, low-step, wet-chemistry, colorimetric assays for three target biomarkers, namely, glucose, uric acid, and free cholesterol, relevant in diabetes control and their translation into paper-based assays and microfluidic platforms for multiplexed analysis. For glucose determination, an in situ AuNPs synthesis approach was applied into the developed µPAD, giving semiquantitative measures in the physiologically relevant range. For uric acid and cholesterol determination, modified AuNPs were used to functionalize paper with a gold-on-paper approach with the optical properties changing based on different aggregation degrees and hydrophobic properties of particles dependent on analyte concentration. These paper-based assays show sensitivity ranges and limits of detection compatible for target analyte level determination and detection limits comparable to those of similar enzymatic, colorimetric systems, relying only on plasmonic transduction without the need for enzymatic activity or other chromogenic substrates. The resulting paper-based assays were integrated into a single 3D, multiplex paper-based device using paper microfluidics, showing the capability for performing different colorimetric assays with distinct requirements in terms of sample flow and sample uptake in test zones using a combination of both horizontal and vertical flows inside the same device. The presented device allows for multiparametric, colorimetric measures of different metabolite levels from a single complex sample matrix drop using digital color analysis, showing the potential for development of low-cost, low-complexity tools for diagnostics toward the point-of-care.


Assuntos
Colorimetria/instrumentação , Ouro/química , Dispositivos Lab-On-A-Chip , Nanopartículas Metálicas/química , Papel , Animais , Biomarcadores/sangue , Glicemia/análise , Colesterol/sangue , Desenho de Equipamento , Cabras , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Ácido Úrico/análise
4.
Nutr. hosp ; 37(6): 1130-1134, nov.-dic. 2020. tab
Artigo em Inglês | IBECS | ID: ibc-198303

RESUMO

INTRODUCTION: obese patients present an inflammatory and metabolic profile that leads to oxidative stress and cellular damage. Phase angle is an indicator of cellular integrity and has been proposed as a prognostic parameter for changes in the metabolic profile. OBJECTIVE: to investigate the possible association between phase angle and metabolic parameters in obese patients. MATERIAL AND METHOD: this was a cross-sectional study of adult obese patients who attended a specialized clinic between 2014 and 2016. All patients were ≥ 18 years of age, with a body mass index ≥ 35 kg/m2. All data were obtained from medical records and made part of the clinical protocol. Patients were divided into two groups using a cutoff point for phase angle, and the groups were compared using the Kruskal-Wallis or Chi-squared test for quantitative and categorical variables, respectively. Correlations were identified by Spearman's and Pearson's correlation analyses. All between-group differences were considered statistically significant at p ≤ 0.05. RESULTS: a low phase angle was present in 30.5 % of the 141 patients enrolled in the study. We found an association between low phase angle and presence of hyperuricemia (p = 0.018) when adjusted for waist circumference, dysglycemia, arterial hypertension, and hyperuricemia. There was no correlation between phase angle and the components of body composition. CONCLUSIONS: there is an association of phase angle with uric acid levels, but not with other metabolic parameters


INTRODUCCIÓN: los pacientes obesos presentan un perfil inflamatorio y metabólico que provoca estrés oxidativo y daño celular. El ángulo de fase es un indicador de integridad celular que se ha propuesto como parámetro pronóstico de los cambios del perfil metabólico. OBJETIVO: investigar la posible asociación entre el ángulo de fase y los parámetros metabólicos en pacientes obesos. MATERIAL Y MÉTODO: estudio transversal de pacientes obesos adultos que asistieron a una clínica especializada entre 2014 y 2016. Todos los pacientes tenían ≥ 18 años de edad y un índice de masa corporal ≥ 35 kg/m2. Todos los datos se obtuvieron de los registros médicos y formaron parte del protocolo clínico. Los pacientes se dividieron en dos grupos usando un punto de corte para el ángulo de fase, y los grupos se compararon usando la prueba de Kruskal-Wallis o del chi cuadrado para las variables cuantitativas y categóricas, respectivamente. Las correlaciones se identificaron mediante el análisis de correlación de Spearman y el de Pearson. Todas las diferencias entre grupos se consideraron estadísticamente significativas si p ≤ 0.05. RESULTADOS: se observó un ángulo de fase bajo en el 30,5 % de los 141 pacientes incluidos en el estudio. Encontramos una asociación entre el ángulo de fase bajo y la presencia de hiperuricemia (p = 0.018) cuando se ajustó para la circunferencia de la cintura, la disglucemia, la hipertensión arterial y la hiperuricemia. No hubo correlación entre el ángulo de fase y los componentes de la composición corporal. CONCLUSIONES: el ángulo de fase presenta asociación con los niveles plasmáticos de ácido úrico pero no con otros parámetros metabólicos


Assuntos
Humanos , Feminino , Adulto , Obesidade/diagnóstico , Síndrome Metabólica/complicações , Síndrome Metabólica/fisiopatologia , Índice de Gravidade de Doença , Relação Cintura-Quadril/métodos , Composição Corporal , Estudos Transversais , Índice de Massa Corporal , Estatísticas não Paramétricas , Hiperuricemia/complicações , Ácido Úrico/análise
5.
Rev. cuba. invest. bioméd ; 39(4): e528, oct.-dic. 2020. graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1156460

RESUMO

Introducción: Las enfermedades cardiovasculares constituyen la principal causa de mortalidad y morbilidad a nivel mundial. Reconocidas como problemas de salud de impacto social, han motivado a muchos científicos a tratar de explicar su patogénesis. Actualmente se plantea de la existencia de otros factores de riesgo, independientemente de los clásicos. Entre estos factores se describen el papel de las altas concentraciones de ácido úrico y la actividad de la enzima gamma-glutamiltransferasa en sangre, biomarcadores de estrés oxidativo. Estos elementos que de manera individual pudieran contribuir a las enfermedades cardiovasculares, parecen tener un efecto sinérgico. Objetivo: Revisar las evidencias que sostienen que altas concentraciones de ácido úrico y la actividad de la enzima gamma-glutamiltransferasa en sangre pueden constituir factores de riesgo que desde el estrés oxidativo contribuyan a las enfermedades cardiovasculares. Métodos: Se recopiló la información a partir de las bases de datos de diferentes buscadores (Medline-Pubmed, Cochrane, Scopus y SciELO) entre el 1 de marzo del 2019 y el 23 de mayo 2020. Conclusiones: Se encontró que, tanto el ácido úrico como la gamma-glutamiltransferasa son productos horméticos que a bajas concentraciones tienen efecto antioxidante en el organismo, pero al elevarse involucran la ocurrencia de procesos oxidativos que conducen a la disfunción endotelial y las enfermedades cardiovasculares(AU)


Introduction: Cardiovascular diseases are the leading cause of mortality and morbidity worldwide. Recognized as a health problem of social impact; they have prompted many scientists to try to explain their pathogenesis. New risk factors are currently acknowledged alongside the classic ones. These factors include the role of high uric acid concentrations and the activity of the enzyme gamma-glutamyltransferase in blood, both of which are biomarkers of oxidative stress. These elements may individually contribute to the development of cardiovascular diseases, and seem to have a synergistic effect. Objective: Review the evidence supporting the idea that high uric acid concentrations and the activity of the enzyme gamma-glutamyltransferase in blood may be risk factors contributing to the development of cardiovascular diseases via oxidative stress. Methods: Data were collected from the databases of various search engines (Medline-Pubmed, Cochrane, Scopus and SciELO) from 1 March 2019 to 23 May 2020. Conclusions: It was found that uric acid and gamma-glutamyltransferase are hormetic products causing an antioxidant effect on the organism at low concentrations. However, when concentrations rise, they are involved in the occurrence of oxidative processes leading to endothelial dysfunction and cardiovascular diseases(AU)


Assuntos
Humanos , Ácido Úrico/análise , Biomarcadores/metabolismo , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/etiologia , Estresse Oxidativo/fisiologia , gama-Glutamiltransferase/análise
6.
Life Sci ; 260: 118307, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841665

RESUMO

AIM: Liver plays a crucial role in innate immunity reactions. This role predisposes the liver to innate-mediated liver injury when uncontrolled inflammation occurs. In this study, the effect of febuxostat administration on acute liver injury induced by concanavalin A (Con A) injection into mouse eye orbital sinus was studied. MATERIALS AND METHODS: Two doses of febuxostat (10 and 20 mg/kg, orally) were administered either 1 h before or 30 min after the administration of Con A. Febuxostat at a low dose (10 mg/kg) before and after Con A modulated the elevation of serum ALT, liver uric acid, liver myeloperoxidase (MPO), and interleukin-1ß (IL-1ß) induced by Con A. The same dose of febuxostat before Con A also decreased serum total bilirubin and neutrophil infiltration, as evidenced by flow cytometry and histopathological analysis. KEY FINDINGS: Febuxostat at a high dose (20 mg/kg) significantly improved serum ALT, AST, albumin, total bilirubin, liver uric acid, MPO, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), interleukin-4 (IL-4), IL-1ß, and neutrophil infiltration induced by Con A administration. The results of histopathological examination of liver cells paralleled the observed biochemical improvements. Hepatocyte apoptosis as evidenced by immunohistochemical examination of cleaved caspase-3 was markedly decreased in the febuxostat protection and treatment groups, in a dose-dependent manner SIGNIFICANCE: These results indicate that febuxostat, especially at the higher dose, may be an effective inhibitor of immune reactions evoked by Con A administration.


Assuntos
Quimiocina CCL2/análise , Concanavalina A/farmacocinética , Febuxostat/administração & dosagem , Hepatite/prevenção & controle , Interleucina-1beta/análise , Fator de Necrose Tumoral alfa/análise , Animais , Apoptose/efeitos dos fármacos , Caspase 3/análise , Febuxostat/farmacologia , Hepatite/imunologia , Hepatite/fisiopatologia , Fígado/química , Fígado/patologia , Fígado/fisiopatologia , Masculino , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Peroxidase/análise , Ácido Úrico/análise
7.
Ecotoxicol Environ Saf ; 201: 110872, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32559693

RESUMO

Based on a hybrid carbon nanotube composite, a novel electrochemical sensor with high sensitivity and selectivity was designed for the simultaneous determination of dopamine (DA) and uric acid (UA). The hybrid carbon nanotube composite was prepared by ultrasonic assembly of carboxylated multi-walled carbon nanotube (MWCNT-COOH) and hydroxylated single-walled carbon nanotube (SWCNT-OH). And the hybrid (MWCNT-COOH/SWCNT-OH) composite was characterized by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FT-IR) spectroscopy. The electrochemical performances of MWCNT-COOH/SWCNT-OH composite modified glassy carbon electrode (MWCNT-COOH/SWCNT-OH/GCE) were analyzed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Under the optimum experimental conditions, the as-prepared sensor showed high sensitivity and selectivity for DA and UA. The calibration curves obtained were linear for the currents versus DA and UA concentrations in the range 2-150 µM, and limits of detection (LODs) were calculated to be 0.37 µM and 0.61 µM (signal-to-noise ratio of 3, S/N = 3), respectively. The recoveries of DA and UA in bovine serum samples at MWCNT-COOH/SWCNT-OH/GCE were in the range 96.18-105.02%, and relative standard deviations (RSDs) were 3.34-7.27%. The proposed electrochemical sensor showed good anti-interference ability, excellent reproducibility and stability, as well as high selectivity, which might provide a promising platform for determination of DA and UA.


Assuntos
Dopamina/análise , Técnicas Eletroquímicas/métodos , Nanotubos de Carbono/química , Ácido Úrico/análise , Animais , Carbono , Bovinos , Dopamina/sangue , Eletrodos , Limite de Detecção , Nanotubos de Carbono/ultraestrutura , Reprodutibilidade dos Testes , Ácido Úrico/sangue
8.
Nat Rev Rheumatol ; 16(7): 380-390, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32541923

RESUMO

Gout is the most common inflammatory arthritis and occurs when hyperuricaemia, sustained elevation of serum urate levels resulting in supersaturation of body tissues with urate, leads to the formation and deposition of monosodium urate crystals in and around the joints. Recent reports of the prevalence and incidence of gout vary widely according to the population studied and methods employed but range from a prevalence of <1% to 6.8% and an incidence of 0.58-2.89 per 1,000 person-years. Gout is more prevalent in men than in women, with increasing age, and in some ethnic groups. Despite rising prevalence and incidence, suboptimal management of gout continues in many countries. Typically, only a third to half of patients with gout receive urate-lowering therapy, which is a definitive, curative treatment, and fewer than a half of patients adhere to treatment. Many gout risk factors exist, including obesity, dietary factors and comorbid conditions. As well as a firmly established increased risk of cardiovascular disease and chronic kidney disease in those with gout, novel associations of gout with other comorbidities have been reported, including erectile dysfunction, atrial fibrillation, obstructive sleep apnoea, osteoporosis and venous thromboembolism. Discrete patterns of comorbidity clustering in individuals with gout have been described. Increasing prevalence and incidence of obesity and comorbidities are likely to contribute substantially to the rising burden of gout.


Assuntos
Supressores da Gota/uso terapêutico , Gota/tratamento farmacológico , Hiperuricemia/complicações , Obesidade/complicações , Adulto , Idoso , Estudos de Casos e Controles , Comorbidade , Grupos Étnicos , Feminino , Gota/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Ácido Úrico/análise
9.
PLoS One ; 15(6): e0234363, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502184

RESUMO

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous disease, with oxidative stress and inflammation implicated in its development. Uric acid (UA) could exert anti-oxidative, pro-oxidative or pro-inflammatory effects, depending on the specific context. It was recently shown that soluble UA, and not just its crystals, could activate the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, leading to interleukin (IL)-1ß secretion. We aimed to assess the differences in blood levels of UA and its ratio with creatinine (UCR) between COPD patients and healthy subjects, as well as their association with disease severity, smoking status, common COPD comorbidities and therapy regimes. The diagnostic characteristics of UA and UCR were also explored. This study included 109 stable COPD patients and 95 controls and measured white blood cells (WBC), C-reactive protein (CRP), fibrinogen (Fbg), IL-1ß, creatinine (CREAT) and UA. All of the parameters were increased in COPD patients, except for CREAT. UA and UCR were positively associated with WBC, CRP and IL-1ß. COPD smokers had lower UA and UCR values. Common COPD therapy did not affect UA or UCR, while patients with cardiovascular diseases (CVD) had higher UA, but not UCR, levels. Patients with higher UCR values showed worse disease-related outcomes (lung function, symptoms, quality of life, history of exacerbations, BODCAT and BODEx). Also, UCR differentiated patients with different severity of airflow limitation as well as symptoms and exacerbations. The great individual predictive potential of UCR and IL-1ß was observed with their odds ratios (OR) being 2.09 and 5.53, respectively. Multiparameter models of UA and UCR that included IL-1ß were able to correctly classify 86% and 90% of cases, respectively. We suggest that UA might be a useful biomarker when combined with IL-1ß, while UCR might be even more informative and useful in overall COPD assessments.


Assuntos
Creatinina/análise , Doença Pulmonar Obstrutiva Crônica/classificação , Doença Pulmonar Obstrutiva Crônica/metabolismo , Ácido Úrico/análise , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Creatinina/sangue , Citocinas/metabolismo , Feminino , Fibrinogênio/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação , Interleucina-1beta/análise , Interleucina-1beta/sangue , Interleucina-1beta/metabolismo , Contagem de Leucócitos/métodos , Masculino , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Índice de Gravidade de Doença , Ácido Úrico/sangue
10.
Tunis Med ; 98(2): 144-149, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32395804

RESUMO

BACKGROUND: Glaucoma is an optic neuropathy induced by many factors. Vascular dysfunction is involved in the mechanism underlying glaucoma. AIM: To determine the involvement of nitric oxide (NO), which is implicated in the regulation of ocular blood flow, in primary open angle glaucoma (POAG). Furthermore, lactate and uric acid (UA) levels were investigated. METHODS: Concentrations of NO, UA and lactate in plasma and aqueous humor (AH) were measured in 214 Tunisian patients (100 patients with POAG and 114 subjects with cataract as control group). NO metabolites, nitrate and nitrite (NOx) production were determined using the Griess reaction. UA and lactate concentrations were measured using enzymatic- colorimetric methods. RESULTS: NOx concentrations in patients with POAG were significantly lower compared to cataract group in plasma (5.23±1.55 µmol/L vs 18.35±6.87 µmol/L, p=0.01) and AH (20.54±7.41 µmol/L vs 45.25±10.92 µmol/L, p=0.02). Plasma and AH levels of lactate and UA were significantly higher in glaucoma patients than in control subjects. CONCLUSIONS: In the present study, decreased NO and increased UA and lactate levels were found in the AH and plasma of POAG patients compared to control subjects. These data suggest a possible involvement of these factors in glaucoma.


Assuntos
Glaucoma de Ângulo Aberto/metabolismo , Óxido Nítrico/metabolismo , Humor Aquoso/química , Humor Aquoso/metabolismo , Análise Química do Sangue , Estudos de Casos e Controles , Catarata/sangue , Catarata/metabolismo , Catarata/patologia , Feminino , Glaucoma de Ângulo Aberto/sangue , Glaucoma de Ângulo Aberto/patologia , Humanos , Ácido Láctico/análise , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Masculino , Óxido Nítrico/análise , Óxido Nítrico/sangue , Tunísia , Ácido Úrico/análise , Ácido Úrico/sangue , Ácido Úrico/metabolismo
11.
Medicine (Baltimore) ; 99(17): e19959, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32332681

RESUMO

This study aimed to investigate the association between Serum Uric Acid (UA) to Creatinine (Cr) Ratio (UA/Cr) and metabolic syndrome (MetS) in postmenopausal women.A total of 455 patients with MetS and 457 age- and gender- matched controls were included in the present retrospective study. Serum levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), Cr, and UA were measured. We employed logistic regression analysis to investigate the association between serum UA/Cr and MetS in postmenopausal women.Serum UA/Cr levels were significantly higher in patients with MetS than that in control subjects (P < .05). In the correlation analysis, serum UA/Cr showed a significantly positive correlation with age, hypertension, systolic pressure (SBP), diastolic pressure (DBP), Waist, body mass index (BMI), TG, UA and negative correlation with type 2 diabetes mellitus (T2DM) and Cr (P all < .001). Moreover, multivariate analysis revealed that serum UA/Cr was still an independent risk factor for MetS (OR = 2.928, 95% CI = 2.385-3.596, P < .001) after adjustments for other confounders.Serum UA/Cr are strongly associated with the risk of MetS in postmenopausal Chinese women.


Assuntos
Creatinina/análise , Síndrome Metabólica/sangue , Ácido Úrico/análise , Idoso , Índice de Massa Corporal , China , Creatinina/sangue , Feminino , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Estudos Retrospectivos , Fatores de Risco , Ácido Úrico/sangue , Circunferência da Cintura
12.
Medicine (Baltimore) ; 99(9): e19418, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32118796

RESUMO

Few studies on the individual and combined analysis between serum uric acid (SUA) and body mass index (BMI) and blood pressure (BP) were conducted in individuals aged ≥45 years. We aimed to assess the extent to which BMI and SUA and their interaction affect BP in Chinese middle-aged and older adults.Data were selected from the China Health and Retirement Longitudinal Study (CHARLS). A total of 5888 individuals aged 45 to 96 was included. Differences between BMI, or between categories of blood pressure were evaluated by t test or chi-square test. The trend of related variables according to four BMI categories was also tested using contrast analysis. The adjusted associations between various characteristics and BP status were first compared using linear regression models, as appropriate. Then, general linear models adjusting for related potential confounders were used to examine the synergistic effect of SUA and BMI level on BP for middle-aged and elderly individuals in China.Age-adjusted partial Pearson correlation coefficient showed that BMI was significantly and positively correlated with BP both in male and female, SUA positively correlated with both systolic blood pressure (SBP) and diastolic blood pressure (DBP) in males with BMI <24.0 kg/m and females with BMI <24.0 kg/m. However, SUA level significantly and positively correlated with DBP, but not with SBP, in females with BMI ≥24.0 kg/m. Multiple linear regression analysis showed that BMI was independently associated with BP both in male and female, SUA significantly and positively associated with SBP in both males and females with BMI <24.0 kg/m, However, SUA level positively correlated with DBP in females with BMI <24.0 kg/m, but not with males with BMI <24.0 kg/m, independent of other confounding factors. A general linear model analysis adjusted for confounding factors did not reveal interaction between BMI, SUA levels and SBP (ß=-1.404, P = .686 in males; ß=-2.583, P = .575 in females) and DBP (ß=-2.544, P = .263 in males; ß=-2.619, P = .622 in females).No interaction between BMI, SUA levels, and BP was observed in either males or females; However, BMI was independently associated with BP both in male and female, SUA independently associated with SBP both in males and females with BMI <24.0 kg/m, and SUA independently associated with DBP in females with BMI ≥24.0 kg/m.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Ácido Úrico/análise , Adulto , Idoso , Determinação da Pressão Arterial/métodos , China , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
13.
Dalton Trans ; 49(14): 4343-4351, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32163086

RESUMO

A facile optical sensor for uric acid (UA), an early pathological signature for the metabolic function of humans, was developed based on water-stable coordination polymers (CPs). Herein, three new isostructural fluorescent CPs, [Ln(TCPB)(DMF)3]n (Ln = La, CP 1; Ce, CP 2 and Pr, CP 3; H3TCPB = 1,3,5-tris(1-(2-carboxyphenyl)-1H-pyrazol-3-yl)benzene), with various metal ions were solvothermally synthesized. Significantly, by regulating the metal-organic coordination interactions, the fabricated CP 3 can quantitatively recognize UA with higher sensitivity compared with CP 1 and CP 2. The mechanism for the sensing properties further demonstrates the best performance of CP 3 and the excellent selectivity for UA monitoring. This work represents the strategy of designing fluorescent CP sensors to determine UA and provides a convenient approach for developing analysis platforms for the assessment of related disease progress and human health monitoring.


Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Elementos da Série dos Lantanídeos/química , Polímeros/química , Ácido Úrico/análise , Técnicas Biossensoriais , Complexos de Coordenação/síntese química , Corantes Fluorescentes/síntese química , Humanos , Modelos Moleculares , Estrutura Molecular , Espectrometria de Fluorescência , Ácido Úrico/metabolismo
14.
Biosensors (Basel) ; 10(3)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204548

RESUMO

We demonstrate a facile methodology for the mass production of graphene oxide (GO) bulk-modified screen-printed electrodes (GO-SPEs) that are economical, highly reproducible and provide analytically useful outputs. Through fabricating GO-SPEs with varying percentage mass incorporations (2.5%, 5%, 7.5% and 10%) of GO, an electrocatalytic effect towards the chosen electroanalytical probes is observed, which increases with greater GO incorporated compared to bare/graphite SPEs. The optimum mass ratio of 10% GO to 90% carbon ink produces an electroanalytical signal towards dopamine (DA) and uric acid (UA) which is ca. ×10 greater in magnitude than that achievable at a bare/unmodified graphite SPE. Furthermore, 10% GO-SPEs exhibit a competitively low limit of detection (3σ) towards DA at ca. 81 nM, which is superior to that of a bare/unmodified graphite SPE at ca. 780 nM. The improved analytical response is attributed to the large number of oxygenated species inhabiting the edge and defect sites of the GO nanosheets, which are able to exhibit electrocatalytic responses towards inner-sphere electrochemical analytes. Our reported methodology is simple, scalable, and cost effective for the fabrication of GO-SPEs that display highly competitive LODs and are of significant interest for use in commercial and medicinal applications.


Assuntos
Dopamina/análise , Grafite/química , Ácido Úrico/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Desenho de Equipamento , Limite de Detecção
15.
Sensors (Basel) ; 20(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32053932

RESUMO

Gout is a condition that affects over 8 million Americans. This condition is characterized by severe pain, and in more advanced cases, bone erosion and joint destruction. This study explores the fabrication and characterization of an optical, enzymatic urate biosensor for gout management, and the optimization of the biosensor response through the tuning of hydrogel matrix properties. Sensors were fabricated through the co-immobilization of oxygen-quenched phosphorescent probes with an oxidoreductase within a biocompatible copolymer hydrogel matrix. Characterization of the spectral properties and hydrogel swelling was conducted, as well as evaluation of the response sensitivity and long-term stability of the urate biosensor. The findings indicate that increased acrylamide concentration improved the biosensor response by yielding an increased sensitivity and reduced lower limit of detection. However, the repeatability and stability tests highlighted some possible areas of improvement, with a consistent response drift observed during repeatability testing and a reduction in response seen after long-term storage tests. Overall, this study demonstrates the potential of an on-demand, patient-friendly gout management tool, while paving the way for a future multi-analyte biosensor based on this sensing platform.


Assuntos
Técnicas Biossensoriais/métodos , Metaloporfirinas/química , Urato Oxidase/metabolismo , Ácido Úrico/análise , Técnicas Biossensoriais/instrumentação , Enzimas Imobilizadas , Humanos , Hidrogéis/química , Luz , Limite de Detecção , Oxigênio/química , Oxigênio/metabolismo , Urato Oxidase/química , Ácido Úrico/metabolismo
16.
BJU Int ; 125(6): 920-924, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32045113

RESUMO

OBJECTIVES: To assess the recall of a deep learning (DL) method to automatically detect kidney stones composition from digital photographs of stones. MATERIALS AND METHODS: A total of 63 human kidney stones of varied compositions were obtained from a stone laboratory including calcium oxalate monohydrate (COM), uric acid (UA), magnesium ammonium phosphate hexahydrate (MAPH/struvite), calcium hydrogen phosphate dihydrate (CHPD/brushite), and cystine stones. At least two images of the stones, both surface and inner core, were captured on a digital camera for all stones. A deep convolutional neural network (CNN), ResNet-101 (ResNet, Microsoft), was applied as a multi-class classification model, to each image. This model was assessed using leave-one-out cross-validation with the primary outcome being network prediction recall. RESULTS: The composition prediction recall for each composition was as follows: UA 94% (n = 17), COM 90% (n = 21), MAPH/struvite 86% (n = 7), cystine 75% (n = 4), CHPD/brushite 71% (n = 14). The overall weighted recall of the CNNs composition analysis was 85% for the entire cohort. Specificity and precision for each stone type were as follows: UA (97.83%, 94.12%), COM (97.62%, 95%), struvite (91.84%, 71.43%), cystine (98.31%, 75%), and brushite (96.43%, 75%). CONCLUSION: Deep CNNs can be used to identify kidney stone composition from digital photographs with good recall. Future work is needed to see if DL can be used for detecting stone composition during digital endoscopy. This technology may enable integrated endoscopic and laser systems that automatically provide laser settings based on stone composition recognition with the goal to improve surgical efficiency.


Assuntos
Algoritmos , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Cálculos Renais/química , Cálculos Renais/diagnóstico por imagem , Oxalato de Cálcio/análise , Fosfatos de Cálcio/análise , Cistina/análise , Humanos , Fotografação , Curva ROC , Estruvita/análise , Ácido Úrico/análise
17.
Mikrochim Acta ; 187(1): 94, 2020 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902014

RESUMO

Poly(3,4-ethylenedioxythiophene) (PEDOT) films were electrodeposited by cyclic voltammetry on a glassy carbon electrode (GCE) in aqueous solution. Three kinds of supporting electrolytes were used, viz. graphene oxide (GO), phosphate buffered saline (PBS), and GO in PBS, respectively. The surface morphology of the modified electrodes was characterized by scanning electron microscopy. The electrochemical performance of the modified electrodes was investigated by cyclic voltammetry and electrochemical impedance spectroscopy by using the hexacyanoferrate redox system. The results demonstrate that the PEDOT-GO/GCE, which was electropolymerized in aqueous solutions containing EDOT and GO, shows the best electrochemical activities compared with other modified electrodes. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) were investigated by cyclic voltammetry. The PEDOT-GO/GCE exhibits enhanced electrocatalytic activities towards these important biomolecules. Under physiological pH conditions and in the mixed system of AA, DA and UA, the modified GCE exhibits the following figures of merit: (a) a linear voltammetric response in the concentration ranges of 100-1000 µM for AA, 6.0-200 µM for DA, and 40-240 µM for UA; (b) well separated oxidation peaks near 31, 213 and 342 mV (vs. saturated Ag/AgCl) for AA, DA and UA, respectively; and (c) detection of limits (at S/N = 3) of 20, 2.0 and 10 µM. The results demonstrate that GO, based on its relatively large number of anionic sites, can be used as the sole weak electrolyte and charge balance dopant for the preparation of functionally doped conducting polymers by electrodeposition. Graphical abstractSchematic representation of a nanostructure composed of hybrid conducting polymer PEDOT-GO nanocomposites, and its application to simultaneous determination of ascorbic acid, dopamine and uric acid.


Assuntos
Ácido Ascórbico/análise , Dopamina/análise , Técnicas Eletroquímicas/métodos , Ácido Úrico/análise , Compostos Bicíclicos Heterocíclicos com Pontes , Técnicas Eletroquímicas/normas , Eletrodos , Galvanoplastia/métodos , Ferrocianetos/química , Grafite , Oxirredução , Polímeros
18.
Mikrochim Acta ; 187(1): 82, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897862

RESUMO

An electrochemical sensor is described for the simultaneous voltammetric determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA). An indium-tin oxide (ITO) electrode was modified with a hierarchical core-shell metal-organic framework and Ag-doped mesoporous metal-oxide based hybrid nanocomposites on g-C3N4 nanosheets. The morphology, structural and chemical composition of the hybrid nanocomposite was characterized using different analytical methods. The modified ITO showed superior electrocatalytic performance towards the oxidation of AA, DA and UA due to the enhanced surface area, synergistic effects and well-organized porous assembly. Figures of merit, include (a) linear responses from 0.1 to 200 µM, 2.5 to 100 µM and 2.5 to 625 µM; (b) detection limits (at S/N = 3) of 0.02, 0.01 and 0.06 µM, and (c) well separated oxidation peaks near -50, 186 and 390 mV (vs. Ag/AgCl) for simultaneous sensing AA, DA and UA, respectively. The sensor was evaluated by analysing spiked serum samples and gave data with precision, with recoveries of >98%. Graphical abstractSchematic Representation of a Mesoporous Silver-doped TiO2-SnO2 Nanocomposite (h-ATS) on g-C3N4 Nanosheets and Decorated with a Hierarchical Core-Shell Metal-Organic Framework (NC@GC) Based Electrochemical Sensor for Simultaneous Voltammetric Detection of Ascorbic acid, Dopamine and Uric acid.


Assuntos
Ácido Ascórbico/análise , Dopamina/análise , Eletroquímica/métodos , Estruturas Metalorgânicas/química , Nanocompostos/química , Nanoestruturas/química , Ácido Úrico/análise , Ácido Ascórbico/sangue , Dopamina/sangue , Eletroquímica/normas , Eletrodos , Grafite/química , Compostos de Nitrogênio/química , Prata , Compostos de Estanho , Titânio , Ácido Úrico/sangue
19.
Analyst ; 145(5): 1903-1909, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31984381

RESUMO

Voltammetric analysis is often dependent on pH and on the addition of buffer reagents to optimise the analytical procedure. This approach is not always possible for in situ analytical measurements, for example when studying biological fluids or ingredients in food. Therefore, a method is proposed herein, which employs a working electrode to do both, that is, to locally modulate the pH value and to measure the analytical response. As a model system, thiamine (vitamin B1) is detected in aqueous KCl with a pH modulation brought about with negative potentials applied to the working electrode. Interferences from ascorbic acid and uric acid are considered. Exploratory data are presented and methods for improving the detection limit are suggested. Their potential for applications in electroanalysis (and in a broader range of processes) is discussed and the detection of thiamine in rice is demonstrated.


Assuntos
Carbono/química , Eletroquímica/métodos , Eletrodos , Oryza/metabolismo , Tiamina/análise , Ácido Ascórbico/análise , Concentração de Íons de Hidrogênio , Ácido Úrico/análise
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