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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 153: 428-35, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26361214

RESUMO

Ag2W(1-x)MoxO4 (x=0.0 and 0.50) powders were synthesized by the co-precipitation (drop-by-drop) method and processed using a microwave-assisted hydrothermal method. We report the real-time in situ formation and growth of Ag filaments on the Ag2W(1-x)MoxO4 crystals using an accelerated electron beam under high vacuum. Various techniques were used to evaluate the influence of the network-former substitution on the structural and optical properties, including photoluminescence (PL) emission, of these materials. X-ray diffraction results confirmed the phases obtained by the synthesis methods. Raman spectroscopy revealed significant changes in local order-disorder as a function of the network-former substitution. Field-emission scanning electron microscopy was used to determine the shape as well as dimensions of the Ag2W(1-x)MoxO4 heterostructures. The PL spectra showed that the PL-emission intensities of Ag2W(1-x)MoxO4 were greater than those of pure Ag2WO4, probably because of the increase of intermediary energy levels within the band gap of the Ag2W(1-x)MoxO4 heterostructures, as evidenced by the decrease in the band-gap values measured by ultraviolet-visible spectroscopy.

2.
Rev. bras. plantas med ; 17(4,supl.2): 881-890, 2015. tab, graf
Artigo em Português | LILACS | ID: lil-771161

RESUMO

RESUMO Objetivou-se neste trabalho reconhecer e sistematizar o conhecimento tradicional sobre as espécies medicinais, as indicações terapêuticas, as formas de uso e as técnicas de produção e comercialização de plantas medicinais no agreste nordestino, no município de Solânea, Paraíba. Visitas, entrevistas e amostragem foram realizadas a agricultores familiares da região por meio de entrevistas semiestruturadas utilizando a técnica de turnê guiada. Após as visitas foi identificada uma atriz - informante. Foi feito um herbário com as plantas medicinais encontradas, nas quais foram identificadas e categorizadas quanto às indicações terapêuticas de acordo com a Classificação Estatística Internacional de Doenças e Problemas Relacionados à Saúde. Foram verificadas 59 espécies com propriedades medicinais distribuídas em 36 famílias botânicas, com o predomínio da família Lamiaceae. Enfermidades de afecções digestivas foram as mais indicadas. O chá foi o preparado de maior frequência.


ABSTRACT The aim of this work was to recognize and to order the traditional knowledge about the medicinal species, the therapeutic indications, the application forms, and the productions and marketing techniques of medicinal plants in the dry area of the northeast, in the city of Solanea, Paraíba. Visits, interviews and sampling were conducted to family farmers in the region through semi-structured interviews using the guided tour technique. A herbarium was built with the medicinal plants found and they were identified and classified regarding their therapeutic indications according to the Diseases International Statistical Classification and the Health Related Problems. 59 species with medicinal properties were identified and distributed in 36 different botanical families, with the Lamiaceae family predominance. The tea preparation was the more frequent one.


Assuntos
Humanos , Plantas Medicinais/classificação , Coleta de Dados/métodos , Etnobotânica/instrumentação , Lamiaceae/classificação , Usos Terapêuticos
3.
Int J Sports Med ; 34(4): 293-301, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23059557

RESUMO

The purpose of this study was to test the hypothesis that skeletal muscle adaptations induced by long-term resistance training (RT) are associated with increased myogenic regulatory factors (MRF) and insulin-like growth factor-I (IGF-I) mRNA expression in rats skeletal muscle. Male Wistar rats were divided into 4 groups: 8-week control (C8), 8-week trained (T8), 12-week control (C12) and 12-week trained (T12). Trained rats were submitted to a progressive RT program (4 sets of 10-12 repetitions at 65-75% of the 1RM, 3 day/week), using a squat-training apparatus with electric stimulation. Muscle hypertrophy was determined by measurement of muscle fiber cross-sectional area (CSA) of the muscle fibers, and myogenin, MyoD and IGF-I mRNA expression were measured by RT-qPCR. A hypertrophic stabilization occurred between 8 and 12 weeks of RT (control-relative % area increase, T8: 29% vs. T12: 35%; p>0.05) and was accompanied by the stabilization of myogenin (control-relative % increase, T8: 44.8% vs. T12: 37.7%, p>0.05) and MyoD (control-relative % increase, T8: 22.9% vs. T12: 22.3%, p>0.05) mRNA expression and the return of IGF-I mRNA levels to the baseline (control-relative % increase, T8: 30.1% vs. T12: 1.5%, p<0.05). Moreover, there were significant positive correlations between the muscle fiber CSA and mRNA expression for MyoD (r=0.85, p=0.0001), myogenin (r=0.87, p=0.0001), and IGF-I (r=0.88, p=0.0001). The significant (p<0.05) increase in myogenin, MyoD and IGF-I mRNA expression after 8 weeks was not associated with changes in the fiber-type frequency. In addition, there was a type IIX/D-to-IIA fiber conversion at 12 weeks, even with the stabilization of MyoD and myogenin expression and the return of IGF-I levels to baseline. These results indicate a possible interaction between MRFs and IGF-I in the control of muscle hypertrophy during long-term RT and suggest that these factors are involved more in the regulation of muscle mass than in fiber-type conversion.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/metabolismo , Proteína MyoD/metabolismo , Miogenina/metabolismo , Condicionamento Físico Animal/métodos , Adaptação Fisiológica , Animais , Hipertrofia , Fator de Crescimento Insulin-Like I/genética , Masculino , Músculo Esquelético/patologia , Proteína MyoD/genética , Miogenina/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
4.
Braz J Med Biol Res ; 39(2): 305-12, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16470320

RESUMO

Diets rich in saturated fatty acids are one of the most important causes of atherosclerosis in men, and have been replaced with diets rich in unsaturated fatty acids (UFA) for the prevention of this disorder. However, the effect of UFA on myocardial performance, metabolism and morphology has not been completely characterized. The objective of the present investigation was to evaluate the effects of a UFA-rich diet on cardiac muscle function, oxidative stress, and morphology. Sixty-day-old male Wistar rats were fed a control (N = 8) or a UFA-rich diet (N = 8) for 60 days. Myocardial performance was studied in isolated papillary muscle by isometric and isotonic contractions under basal conditions after calcium chloride (5.2 mM) and ss-adrenergic stimulation with 1.0 microM isoproterenol. Fragments of the left ventricle free wall were used to study oxidative stress and were analyzed by light microscopy, and the myocardial ultrastructure was examined in left ventricle papillary muscle. After 60 days the UFA-rich diet did not change myocardial function. However, it caused high lipid hydroperoxide (176 +/- 5 vs 158 +/- 5, P < 0.0005) and low catalase (7 +/- 1 vs 9 +/- 1, P < 0.005) and superoxide-dismutase (18 +/- 2 vs 27 +/- 5, P < 0.005) levels, and discrete morphological changes in UFA-rich diet hearts such as lipid deposits and mitochondrial membrane alterations compared to control rats. These data show that a UFA-rich diet caused myocardial oxidative stress and mild structural alterations, but did not change mechanical function.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Insaturados/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Ácidos Graxos Insaturados/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Lipídeos/sangue , Masculino , Microscopia Eletrônica , Contração Miocárdica/fisiologia , Miocárdio/química , Miocárdio/patologia , Tamanho do Órgão , Ratos , Ratos Wistar
5.
Braz. j. med. biol. res ; 39(2): 305-312, Feb. 2006.
Artigo em Inglês | LILACS | ID: lil-420284

RESUMO

Diets rich in saturated fatty acids are one of the most important causes of atherosclerosis in men, and have been replaced with diets rich in unsaturated fatty acids (UFA) for the prevention of this disorder. However, the effect of UFA on myocardial performance, metabolism and morphology has not been completely characterized. The objective of the present investigation was to evaluate the effects of a UFA-rich diet on cardiac muscle function, oxidative stress, and morphology. Sixty-day-old male Wistar rats were fed a control (N = 8) or a UFA-rich diet (N = 8) for 60 days. Myocardial performance was studied in isolated papillary muscle by isometric and isotonic contractions under basal conditions after calcium chloride (5.2 mM) and ß-adrenergic stimulation with 1.0 æM isoproterenol. Fragments of the left ventricle free wall were used to study oxidative stress and were analyzed by light microscopy, and the myocardial ultrastructure was examined in left ventricle papillary muscle. After 60 days the UFA-rich diet did not change myocardial function. However, it caused high lipid hydroperoxide (176 ± 5 vs 158 ± 5, P < 0.0005) and low catalase (7 ± 1 vs 9 ± 1, P < 0.005) and superoxide-dismutase (18 ± 2 vs 27 ± 5, P < 0.005) levels, and discrete morphological changes in UFA-rich diet hearts such as lipid deposits and mitochondrial membrane alterations compared to control rats. These data show that a UFA-rich diet caused myocardial oxidative stress and mild structural alterations, but did not change mechanical function.


Assuntos
Animais , Masculino , Ratos , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Insaturados/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácidos Graxos Insaturados/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Lipídeos/sangue , Microscopia Eletrônica , Contração Miocárdica/fisiologia , Miocárdio/química , Miocárdio/patologia , Tamanho do Órgão , Ratos Wistar
6.
Food Chem Toxicol ; 40(12): 1893-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12419704

RESUMO

The present study examines the effects of caloric restriction in cardiac tissue evaluation markers of oxidative stress. High-fat dietary restrictions can have a long-term impact on cardiac health. Dietary restriction of control diet increased myocardial superoxide dismutase (SOD) and catalase activities. Dietary restriction of fatty acid-enriched diets increased myocardial lipoperoxide concentrations, while SOD activity was decreased in cardiac tissue of rats with dietary restriction of fatty acid-enriched diets. Dietary restriction of unsaturated fatty acid-enriched diet induced the highest lipoperoxide concentration and the lowest myocardial SOD activity. Dietary restriction of unsaturated fatty acid decreased myocardial glycogen, and increased the lactate dehydrogenase/citrate synthase ratio. Dietary restriction of fatty acid-enriched diets were more deleterious to cardiac tissue than normal ad lib.-fed diet. In conclusion, the effects of caloric restriction on myocardial oxidative stress is dependent on which nutrient is restricted. Dietary restriction of fatty acid-enriched diets is deleterious relative to ad lib.-fed chow diet.


Assuntos
Catalase/metabolismo , Dieta com Restrição de Gorduras , Gorduras na Dieta/administração & dosagem , Miocárdio/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Animais , Biomarcadores , Dieta com Restrição de Gorduras/efeitos adversos , Dieta Redutora/efeitos adversos , Gorduras na Dieta/efeitos adversos , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/efeitos adversos , Ingestão de Energia , Masculino , Miocárdio/patologia , Ratos , Ratos Wistar
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