182 research outputs found

    Estudio de la actividad biológica y toxicidad de extractos naturales obtenidos a partir de especies vegetales silvestres

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    El objetivo de este trabajo fue caracterizar extractos acuosos de especies vegetales silvestres en base a su capacidad antioxidante, inhibición del pardeamiento enzimático y citotoxicidad para evaluar su utilización corno aditivos en matrices alimentarias. Además se comparó el calentamiento convencional con el asistido por microonda para realizar los extractos. Se eligieron 16 especies vegetales que tienen o tuvieron alguna utilización como alimento. El material recolectado se clasificó botánicamente, se secó y se molió. Se realizaron extractos acuosos que luego se filtraron y se midieron polifenoles torales por Folin-Ciocalteu, capacidad captadora de radicales libres por DPPH, capacidad de inhibición de la polifenoloxidasa de manzana y toxicidad utilizando el test de Artemia Salina. El proceso de extracción asistido por microondas fue más eficiente en la extracción de polifenoles y sencillo de aplicar usando equipo estándar y de bajo costo. El estudio preliminar de toxicidad mostró valores muy bajos para la mayoría de las especies. Solidago chilensis. Lantana camara y Eryngium horridum mostraron alto contenido de polifenoles y alta actividad captadora de radicales libres. Urtica urens mostró efecto inhibitorio sobre la PPO de manzana junto a una LC50 muy alta. Las especies estudiadas resultaron prometedoras para la búsqueda de compuestos antioxidantes como aditivos alimentarios, el uso de especies comestibles es un buen punto de partida para la selección. Se requieren estudios más profundos sobre la composición de estos extractos para identificar los metabolismos responsables de las características observadas.EEA PergaminoFil: Micheloni, O.B. Universidad Nacional del Noroeste de la Provincia de de Buenos Aires. Departamento de Ciencias Básicas; Argentina.Fil: González, E. Universidad Nacional del Noroeste de la Provincia de de Buenos Aires. Departamento de Ciencias Básicas; Argentina.Fil: Leclerq, B. Universidad Nacional del Noroeste de la Provincia de de Buenos Aires. Departamento de Ciencias Básicas; Argentina.Fil: Rollandeli, G. Universidad Nacional del Noroeste de la Provincia de de Buenos Aires. Departamento de Ciencias Básicas; Argentina.Fil: Oackley, L. Universidad Nacional del Noroeste de la Provincia de de Buenos Aires. Departamento de Ciencias Básicas; Argentina.Fil: Farroni, A.E. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Laboratorio Calidad de Alimento, Suelo y Agua; Argentina

    Randomized, double blind study of non-excitatory, cardiac contractility modulation electrical impulses fr symptomatic heart failure

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    AIMS: We performed a randomized, double blind, crossover study of cardiac contractility modulation (CCM) signals in heart failure patients. METHODS AND RESULTS: One hundred and sixty-four subjects with ejection fraction (EF) < 35% and NYHA Class II (24%) or III (76%) symptoms received a CCM pulse generator. Patients were randomly assigned to Group 1 (n = 80, CCM treatment 3 months, sham treatment second 3 months) or Group 2 (n = 84, sham treatment 3 months, CCM treatment second 3 months). The co-primary endpoints were changes in peak oxygen consumption (VO2,peak) and Minnesota Living with Heart Failure Questionnaire (MLWHFQ). Baseline EF (29.3 +/- 6.7% vs. 29.8 +/- 7.8%), VO2,peak (14.1 +/- 3.0 vs. 13.6 +/- 2.7 mL/kg/min), and MLWHFQ (38.9 +/- 27.4 vs. 36.5 +/- 27.1) were similar between the groups. VO2,peak increased similarly in both groups during the first 3 months (0.40 +/- 3.0 vs. 0.37 +/- 3.3 mL/kg/min, placebo effect). During the next 3 months, VO2,peak decreased in the group switched to sham (-0.86 +/- 3.06 mL/kg/min) and increased in patients switched to active treatment (0.16 +/- 2.50 mL/kg/min). MLWHFQ trended better with treatment (-12.06 +/- 15.33 vs. -9.70 +/- 16.71) during the first 3 months, increased during the second 3 months in the group switched to sham (+4.70 +/- 16.57), and decreased further in patients switched to active treatment (-0.70 +/- 15.13). A comparison of values at the end of active treatment periods vs. end of sham treatment periods indicates statistically significantly improved VO2,peak and MLWHFQ (P = 0.03 for each parameter). CONCLUSION: In patients with heart failure and left ventricular dysfunction, CCM signals appear safe; exercise tolerance and quality of life (MLWHFQ) were significantly better while patients were receiving active treatment with CCM for a 3-month period

    Relationship between self-reported dietary intake and physical activity levels among adolescents: The HELENA study

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    Background Evidence suggests possible synergetic effects of multiple lifestyle behaviors on health risks like obesity and other health outcomes. Therefore it is important to investigate associations between dietary and physical activity behavior, the two most important lifestyle behaviors influencing our energy balance and body composition. The objective of the present study is to describe the relationship between energy, nutrient and food intake and the physical activity level among a large group of European adolescents. Methods The study comprised a total of 2176 adolescents (46.2% male) from ten European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. Dietary intake and physical activity were assessed using validated 24-h dietary recalls and self-reported questionnaires respectively. Analyses of covariance (ANCOVA) were used to compare the energy and nutrient intake and the food consumption between groups of adolescents with different physical activity levels (1st to 3rd tertile). Results In both sexes no differences were found in energy intake between the levels of physical activity. The most active males showed a higher intake of polysaccharides, protein, water and vitamin C and a lower intake of saccharides compared to less active males. Females with the highest physical activity level consumed more polysaccharides compared to their least active peers. Male and female adolescents with the highest physical activity levels, consumed more fruit and milk products and less cheese compared to the least active adolescents. The most active males showed higher intakes of vegetables and meat, fish, eggs, meat substitutes and vegetarian products compared to the least active ones. The least active males reported the highest consumption of grain products and potatoes. Within the female group, significantly lower intakes of bread and cereal products and spreads were found for those reporting to spend most time in moderate to vigorous physical activity. The consumption of foods from the remaining food groups, did not differ between the physical activity levels in both sexes. Conclusion It can be concluded that dietary habits diverge between adolescents with different self-reported physical activity levels. For some food groups a difference in intake could be found, which were reflected in differences in some nutrient intakes. It can also be concluded that physically active adolescents are not always inclined to eat healthier diets than their less active peers.The HELENA study took place with the financial support of the European Community Sixth RTD Framework Programme (Contract FOOD-CT: 2005-007034). This work was also partially supported by the European Union, in the framework of the Public Health Programme (ALPHA project, Ref: 2006120), the Swedish Council for Working Life and Social Research (FAS), the Spanish Ministry of Education (EX-2007-1124, and EX-2008-0641), and the Spanish Ministry of Health, Maternal, Child Health and Development Network (number RD08/0072) (JPRL, LAM)
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