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1.
Anal Bioanal Chem ; 416(11): 2859-2870, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38459967

RESUMEN

Microwave-induced combustion (MIC) was proposed in this study for honey decomposition aiming for As, Cd, Hg, and Pb determination by inductively coupled plasma mass spectrometry (ICP-MS). Sample mass (up to 1.0 g), absorbing solution (0.5 to 14.4 mol L-1 HNO3, and H2O), heating program, and combustion aids were evaluated. The Eurachem guidelines were used for method validation. The proposed method enabled combustion of a high sample mass (0.8 g of honey, with 0.4 g of microcrystalline cellulose and 100 µL of 6 mol L-1 NH4NO3) using 6 mL of an absorbing solution consisting of 1 mol L-1 HNO3, which resulted in low residual carbon in solution (< 25 mg L-1). Honey samples from different geographical origins were analyzed. Results showed no significant difference in comparison to other two microwave decomposition methods, based on microwave-assisted wet digestion with single reaction chamber (MAWD-SRC) and microwave-assisted wet digestion (MAWD). Standard addition experiments resulted in recoveries higher than 98%. The limits of detection ranged from 1.10 (As) to 4.60 ng g-1 (Pb). In addition to using only diluted reagents and resulting in digests virtually free of interferences, the proposed method was faster (< 30 min) than most of those presented in the literature.


Asunto(s)
Miel , Microondas , Espectrometría de Masas/métodos , Plomo , Análisis Espectral
2.
J Agric Food Chem ; 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36972393

RESUMEN

A strategy for determining the bioaccessibility of bromine and iodine from edible seaweeds was proposed for the first time using microwave-induced combustion (MIC) and ion chromatography coupled to mass spectrometry (IC-MS) after in vitro digestion. The concentrations of bromine and iodine in edible seaweeds using the proposed methods (MIC and IC-MS) were not statistically different from those using MIC and inductively coupled plasma mass spectrometry (p > 0.05). Trueness was assessed by recovery experiments (101-110%, relative standard deviation <10%). Following an in vitro digestion protocol, MIC was proposed as sample preparation for bioaccessible and residual fractions. Using this strategy, the mass balance totaled from 97 to 111%. No statistical difference (p > 0.05) was observed between the total concentration of bromine or iodine and their concentration in bioaccessible and residual fractions for three edible seaweed species, indicating full analyte quantification in the fractions.

3.
Pediatr Exerc Sci ; 35(3): 186-194, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36538934

RESUMEN

PURPOSE: To assess the quality of the available evidence on the effect of exercise for the improvement of lung function in healthy children and adolescents. METHOD: We performed a systematic review and meta-analysis of intervention studies examining the effects of regular exercise on spirometric parameters of healthy children and adolescents aged ≤18 years. RESULTS: Within the exercise groups, there were significant improvements in forced vital capacity (mean difference: 0.17 L; 95% confidence interval, 0.07 to 0.26; P < .05) and forced expiratory volume in the first second (mean difference: 0.14 L; 95% confidence interval, 0.06 to 0.22; P < .05). Results were consistent across different age groups and duration of interventions. In the between-group analysis, forced vital capacity, forced expiratory volume in the first second, and peak expiratory flow were higher in the exercise group compared with the nonexercise group, but the differences did not reach statistical relevance. There was significant statistical heterogeneity between studies. CONCLUSION: Regular exercise has the potential to improve lung function parameters in healthy children and adolescents; however, the small number of studies and the heterogeneity between them raise concern about the quality of the currently available evidence. These findings bring to attention the need for well-designed trials addressing this important public health issue.


Asunto(s)
Ejercicio Físico , Pulmón , Humanos , Niño , Adolescente , Capacidad Vital , Volumen Espiratorio Forzado , Espirometría
4.
Ultrason Sonochem ; 72: 105453, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33412386

RESUMEN

Nitrocellulose is a nitrated cellulose polymer with a broad application in industry. Depending on the nitrogen content, this polymer can be used for manufacturing explosives, varnishes, clothes, and films, being considered a product of high value-added. In this work, the use of ultrasound was investigated for the intensification of nitrocellulose synthesis from microcrystalline cellulose. The ultrasound-assisted nitrocellulose synthesis (UANS) was carried out using several ultrasound systems, such as baths and cup horns, allowing the evaluation of the frequency (from 20 to 130 kHz) and delivered power (from 23 to 134 W dm-3) to the reaction medium. The following parameters were evaluated: acid mixture (H2SO4, H3PO4, CH2O2 or CH3COOH with HNO3, 2 to 14.4 mol L-1), ultrasound amplitude (10 to 70%) and reaction time (5 to 50 min). Better nitrocellulose yield (nitrogen content of 12.5% was obtained from 1 g of microcrystalline cellulose employing a cup horn system operating at 20 kHz, 750 W of nominal power with 60% of amplitude, 25 mL of acid solution (13.6 mL of 18.4 mol L-1 H2SO4 + 9.2 mL of 14.4 mol L-1 HNO3 + 2.2 mL H2O), at 30 °C for 30 min. At silent conditions (mechanical stirring ranging from 100 to 500 rpm), the nitrogen content was lower than 11.8% which demonstrate the ultrasound effects for nitrocellulose synthesis.

5.
Anal Bioanal Chem ; 412(24): 6475-6484, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32394040

RESUMEN

The halogen determination is important in view of their biological and environmental roles, but their determination has still been considered a challenge, especially at low concentrations. Therefore, a method for honey decomposition using microwave-induced combustion (MIC) combined with ion chromatography and conductimetric detection (for Cl, F, and S determination) or mass detection (for Br and I determination) (IC-CD-MS) is proposed. Trueness was evaluated by adding reference materials (RMs) or a standard solution in the sample. By using 50 mmol L-1 NH4OH as the absorbing solution, recoveries for all analytes were between 94 and 103%, in both tests. Moreover, no statistical difference (t test, confidence level of 95%) was observed for the results obtained by IC in comparison with those obtained by inductively coupled plasma optical emission spectroscopy (Cl and S) and by inductively coupled plasma mass spectrometry (Br and I). Finally, the proposed method was applied to 19 honey samples from different origins. The concentrations ranged from < 0.45 to 2.39 mg kg-1 (Br), 21.8 to 671 mg kg-1 (Cl), and 11 to 154 mg kg-1 (S), while the F and I concentrations were below that their quantification limits (LOQs) in all analyzed samples. The LOQs for Br, Cl, F, I, and S were 0.45, 21, 3.7, 0.077, and 8.7 mg kg-1, respectively. The MIC method provided a compatible solution to IC for the halogen and S determination in honey by a single analysis. Graphical abstract.


Asunto(s)
Análisis de los Alimentos/métodos , Halógenos/análisis , Miel/análisis , Azufre/análisis , Límite de Detección , Espectrometría de Masas/métodos , Microondas
6.
Lung ; 196(6): 633-642, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30302536

RESUMEN

Quantitative imaging in lung cancer is a rapidly evolving modality in radiology that is changing clinical practice from a qualitative analysis of imaging features to a more dynamic, spatial, and phenotypical characterization of suspected lesions. Some quantitative parameters, such as the use of 18F-FDG PET/CT-derived standard uptake values (SUV), have already been incorporated into current practice as it provides important information for diagnosis, staging, and treatment response of patients with lung cancer. A growing body of evidence is emerging to support the use of quantitative parameters from other modalities. CT-derived volumetric assessment, CT and MRI lung perfusion scans, and diffusion-weighted MRI are some of the examples. Software-assisted technologies are the future of quantitative analyses in order to decrease intra- and inter-observer variability. In the era of "big data", widespread incorporation of radiomics (extracting quantitative information from medical images by converting them into minable high-dimensional data) will allow medical imaging to surpass its current status quo and provide more accurate histological correlations and prognostic value in lung cancer. This is a comprehensive review of some of the quantitative image methods and computer-aided systems to the diagnosis and follow-up of patients with lung cancer.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Neoplasias Pulmonares/diagnóstico por imagen , Imagen de Perfusión/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Nódulo Pulmonar Solitario/diagnóstico por imagen , Inteligencia Artificial , Macrodatos , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética/métodos , Estadificación de Neoplasias , Radiofármacos , Tomografía Computarizada por Rayos X
7.
Lung ; 194(6): 871-879, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27663257

RESUMEN

Histological examination has always been the gold standard for the detection and quantification of lung remodeling. However, this method has some limitations regarding the invasiveness of tissue acquisition. Quantitative imaging methods enable the acquisition of valuable information on lung structure and function without the removal of tissue from the body; thus, they are useful for disease identification and follow-up. This article reviews the various quantitative imaging modalities used currently for the non-invasive study of chronic obstructive pulmonary disease, asthma, and interstitial lung diseases. Some promising computer-aided diagnosis methods are also described.


Asunto(s)
Asma/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Imagen por Resonancia Magnética , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Humanos , Imagenología Tridimensional
8.
Respir Med ; 112: 10-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26860219

RESUMEN

Lymphadenopathy is a common radiological finding in many thoracic diseases and may be caused by a variety of infectious, inflammatory, and neoplastic conditions. This review aims to describe the patterns of mediastinal and hilar lymphadenopathy found in benign diseases in immunocompetent patients. Computed tomography is the method of choice for the evaluation of lymphadenopathy, as it is able to demonstrate increased size of individual nodes, abnormalities of the interface between the mediastinum and lung, invasion of surrounding fat, coalescence of adjacent nodes, obliteration of the mediastinal fat, and hypo- and hyperdensity in lymph nodes. Intravenous contrast enhancement may be needed to help distinguish nodes from vessels. The most frequent infections resulting in this finding are tuberculosis and fungal disease (particularly histoplasmosis and coccidioidomycosis). Sarcoidosis is a relatively frequent cause of lymphadenopathy in young adults, and can be distinguished from other diseases - especially when enlarged lymph nodes are found to be multiple and symmetrical. Other conditions discussed in this review are silicosis, drug reactions, amyloidosis, heart failure, Castleman's disease, viral infections, and chronic obstructive pulmonary disease.


Asunto(s)
Ganglios Linfáticos/diagnóstico por imagen , Enfermedades Linfáticas/diagnóstico por imagen , Amiloidosis/complicaciones , Amiloidosis/diagnóstico , Amiloidosis/diagnóstico por imagen , Beriliosis/complicaciones , Beriliosis/diagnóstico , Beriliosis/diagnóstico por imagen , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/diagnóstico , Enfermedad de Castleman/diagnóstico por imagen , Coccidioidomicosis/complicaciones , Coccidioidomicosis/diagnóstico , Coccidioidomicosis/diagnóstico por imagen , Diagnóstico Diferencial , Hipersensibilidad a las Drogas/complicaciones , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/diagnóstico por imagen , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/diagnóstico por imagen , Histoplasmosis/complicaciones , Histoplasmosis/diagnóstico , Histoplasmosis/diagnóstico por imagen , Humanos , Fibrosis Pulmonar Idiopática/complicaciones , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Enfermedades Pulmonares Fúngicas/complicaciones , Enfermedades Pulmonares Fúngicas/diagnóstico , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Linfadenitis/diagnóstico , Linfadenitis/diagnóstico por imagen , Enfermedades Linfáticas/diagnóstico , Enfermedades Linfáticas/etiología , Mediastino , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/diagnóstico por imagen , Sarcoidosis/complicaciones , Sarcoidosis/diagnóstico , Sarcoidosis/diagnóstico por imagen , Silicosis/complicaciones , Silicosis/diagnóstico , Silicosis/diagnóstico por imagen , Tórax , Tomografía Computarizada por Rayos X , Tuberculosis Ganglionar/complicaciones , Tuberculosis Ganglionar/diagnóstico
9.
Environ Toxicol Pharmacol ; 37(1): 195-201, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24361697

RESUMEN

We evaluated the effects green and mate teas on oxidative and DNA damages in rats exposed to ultraviolet radiation. Were utilized 70 adult male Wistar rats that received daily oral or topic green or mate tea treatment during exposed to radiation by seven days. After, animals were killed by decapitation. Thiobarbituric acid-reactive species levels, protein oxidative damage were evaluated in skin and DNA damage in blood. Our results show that the rats exposed to ultraviolet radiation presented DNA damage in blood and increased protein carbonylation and lipid peroxidation in skin. Oral and topic treatment with green tea and mate tea prevented lipid peroxidation, both treatments with mate tea also prevented DNA damage. However, only topic treatment with green tea and mate tea prevented increases in protein carbonylation. Our findings contribute to elucidate the beneficial effects of green tea and mate tea, here in demonstrated by the antioxidant and antigenotoxic properties presented by these teas.


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Camellia sinensis , Ilex paraguariensis , Extractos Vegetales/farmacología , Rayos Ultravioleta/efectos adversos , Animales , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Carbonilación Proteica/efectos de los fármacos , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
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