Thermogenesis induced by a high-carbohydrate meal in fasted lean and overweight young men: insulin, body fat, and sympathetic nervous system involvement

Objective This dietary trial was designed to evaluate the effect of an experimental short-term fasting period followed by a high-carbohydrate meal on energy expenditure, thermogenesis, and sympathetic nervous system activity in normal (body mass index 27 kg/m2) men who were healthy, non-diabetic or with no other endocrine disease, non-smokers, not taking oral prescription medications, and with a stable body weight for the previous 3 mo. Methods Fasting and fed energy expenditures and diet-induced thermogenesis were measured after a high-carbohydrate meal in seven overweight and six lean young male subjects by indirect calorimetry. Heart rate, urinary excretion of catecholamines, serum glucose, and insulin were also measured over the experimental fasting (7.5 h) and postprandial (4 h) periods. Results After carbohydrate intake, overweight men showed a significantly higher energy production (kJ/kg of fat-free mass) than did lean individuals, and the diet-induced thermogenesis (percentage of energy intake) was positively correlated with body fat (kg), percentage of body fat, fat-free mass (kg), and fasting pre-meal serum insulin levels. Postprandial cumulative energy expenditure was directly associated with postprandial insulin response and with mean postprandial heart rate values. No significant differences in urinary catecholamines were found between lean and overweight men at basal conditions or during the study period. Conclusions Overweight individuals showed similar short-term sympathetic nervous system responses induced by an experimental fasting period. Although diet-induced thermogenesis after carbohydrate intake was not statistically different between lean and overweight men, the postprandial insulin response and body fat content seemed to be involved in sympathetic nervous system activity

Effect of different extraction conditions on the antioxidant potential of baru almonds (Dipteryx alata Vog.): comparison to common nuts from Brazil

The antioxidant properties and total phenols content of baru almonds (Dipteryx alata Vog.) were investigated using different solvents and extraction temperatures, and were compared with other types of nuts commonly consumed in Brazil. Although baru almonds are popular and widely consumed, few studies report on their biological properties and there are no data on optimum extraction conditions. For this reason, we tested five different extraction methodologies (water and methanol at boiling and room temperature, and water : methanol (1 : 1) at room temperature) on baru almonds, and evaluated the antioxidant properties based on scavenging activity, reducing power and total phenols content. The methanolic extraction at room temperature was the best extraction methodology providing the highest general antioxidant potential. The extraction method selected was applied to several dry fruits: baru almonds (three different samples), peanut, cashew nut, crude cashew nut, macadamia and Brazil nut. Among these nut fruits, baru had the highest antioxidant activity and total phenols content. The results obtained revealed that baru almonds are a good source of bioactive compounds, and have a higher bioactivity than many nut fruits widely distributed, consumed and more popular.info:eu-repo/semantics/publishedVersio

Effects of leptin resistance on acute fuel metabolism after a high carbohydrate load in lean and overweight young men

Objective: Six lean (BMI = 20.8 ± 0.7) and seven overweight (BMI = 30.8 ± 1.7) young men (18–27 years old) were studied to investigate the acute effect of a high-carbohydrate meal on leptin levels and its relation to energy expenditure as well as to protein, carbohydrate and fat oxidation. Methods: Study participants were given a high-carbohydrate meal (17% as protein, 80% as carbohydrates and 3% as lipids) covering 40% of their estimated daily energy requirements. Serum leptin, insulin, glucose, free fatty acids and triglycerides levels were measured before meal intake and during the four postprandial hours. Furthermore, energy expenditure (EE), protein, carbohydrate and lipid oxidation were measured in fasted and fed conditions. Results: Fasting leptin was found to be positively correlated with circulating insulin concentrations (r = .748; p = 0.011) and body fat in kg (r = .827; p = 0.001). During the measured postprandial period no statistically significant changes were found in leptin levels as compared with pre-meal values in either lean or overweight men, nor differences in leptin changes between both groups. After load intake, carbohydrate oxidation was lower in overweight individuals (p < 0.05), while no significant differences were observed in protein oxidation. Cumulative lipid oxidation was found to be negatively associated with post-meal leptin values, being significantly lower in the overweight as compared with lean men (p < 0.05). This study demonstrates that the acute postprandial fuel substrate utilization is altered in overweight men with a lower carbohydrate oxidation and a strong inhibition of lipid oxidation, which could be attributed to some leptin resistance. Conclusion: These data also suggest that short-term meal-related metabolic responses may explain the long-term body adiposity if they are sustained over long intervals

Optimizing the choice of microsatellite markers for fingerprinting eucalyptus

In this study we have analyzed the information provided by 17 publicly available Eucalyptus microsatellite (SSR) markers (Brondani et al. 1998, 2002; Jones et al. 2002; Steane et al. 2001) in the context of genetic identification within a sample of 140 individuals from an elite collection (denoted hereafter base) of RAIZ genetic improvement population

A divulgação de informação contabilistica e financeira: Um caso de estudo

Esta investigação discutirá a divulgação de informação, publicada e disponibilizada, pelas Entidades da Comissão do Mercado de Valores Mobiliários (CMVM) e constantes do Sistema de Difusão de Informação (SDI). A metodologia de investigação propõe para a análise teórica, uma revisão de literatura através de uma pesquisa bibliográfica, de modo a contextualizar a divulgação de informação no Relatório de Gestão e Contas (RGC) anual publicados pelas referidas entidades. A análise empírica, de carácter longitudinal exploratório, suportou-se num tratamento, como fonte primária, das referidas entidades. Este procedimento foi depurado por um processo de confirmação da fiabilidade da mesma, recorrendo a outras fontes de verificação dos relatórios anuais. Os resultados evidenciam uma grande dispersão da divulgação da informação o que torna, particularmente, difícil a identificação de variáveis e entidades emitentes do SDI da CMVM, bem como o nível de transparência e cumprimento do dever de divulgação por parte dessas entidades

Molecular estimates of similarity in Eucalyptus globulus

The base populations used in most forest tree genetic improvement programs usually lack detailed pedigree information. Molecular markers, such as microsatellites (SSR), can be used to estimate individuals’ pairwise relatedness, which is based on the probabilities’ ratios of the identity in state between the individuals compared and the reference unrelated population These estimates can be very useful to infer the level of relationship among sub-populations of elite material and/or for the design of controlled crosses between putatively unrelated parents. Using 113 putatively unrelated individuals - genotyped with 18 SSR - self, full-sib, half-sib and unrelated were simulated, and four pairwise similarity coefficients were tested: Queller & Goodnight 1989; Li et al. 1993; Ritland 1996, and Lynch & Ritland 1999. The Lynch & Ritland (1999) coefficient was selected (Figure 1), for it displayed a better adjustment with the expected level of relatedness and narrower standard errors (SE). SE were calculated through Monte- Carlo techniques, to avoid unequal sample size bias, by using 105 simulations for each relatedness group. To illustrate the usefulness of molecular estimates of similarity in genetic improvement programs, a clustering (UPGMA) based on the pairwise Lynch & Ritland (1999) coefficient (LR) values was performed to infer about the putative relationship among individuals of the subgroups of E. globulus elite individuals. From that analysis at least two pairs might be related and a PCA analysis confirmed the clustering results

High-Linearity Self-Biased CMOS Current Buffer

A highly linear fully self-biased class AB current buffer designed in a standard 0.18 mu m CMOS process with 1.8 V power supply is presented in this paper. It is a simple structure that, with a static power consumption of 48 mu W, features an input resistance as low as 89 Omega, high accuracy in the input-output current ratio and total harmonic distortion (THD) figures lower than -60 dB at 30 mu A amplitude signal and 1 kHz frequency. Robustness was proved through Monte Carlo and corner simulations, and finally validated through experimental measurements, showing that the proposed configuration is a suitable choice for high performance low voltage low power applications

Variabilidad espacial y temporal del vigor vegetativo en viñedo sin restricciones hídricas en la demanda evapotranspirativa

Aunque generalmente se asume que la respuesta de un cultivo a la dosis de riego seleccionada es homogénea en la totalidad del área cultivada, en la mayoría de los casos esto no se corresponde con la realidad. En este trabajo se presenta un estudio de la variabilidad espacial y temporal del vigor vegetativo en el cultivo del viñedo, mediante el uso de índices de vegetación (NDVI) y la elaboración de los correspondientes mapas estadísticos. El ensayo ha sido realizado en un viñedo experimental de cultivar Tempranillo (Vitis vinífera L.), donde se compararon cuatro bloques aleatorios con un tratamiento de riego al 100% de la demanda evapotranspirativa (ETc) del cultivo. Durante la fase de maduración, se realizaron semanalmente mapas de índices de vegetación mediante el uso de sensores multiespectrales cercanos, montados sobre vehículos terrestres. Se observó que la respuesta en el desarrollo vegetativo no mantuvo una homogeneidad espacio – temporal en las cuatro zonas de estudio, a pesar de haber recibido las mismas prácticas culturales. La utilización de este tipo de herramientas, sensores de vegetación y estadística inferencial, permite detectar zonas diferenciadas en el desarrollo vegetativo, pudiendo ser utilizado para la toma de decisiones sobre el manejo del cultivo, tales como el escalonamiento de la cosecha o la aplicación tanto de abonos como de fitosanitarios, en función del factor que produce dicho descenso de vegetación

Micro-Terroir

El concepto de terroir en el vino está basado en la observación de que diferentes regiones, viñedos o secciones dentro del mismo viñedo, pueden producir vinos con identidades propias y muy diferentes entre sí. Este concepto se cristalizó con el fin de describir los aspectos únicos de un lugar particular (suelo, topografía y clima) que influyen y forman el vino que nace a partir de él. Para una misma posición geográfica, podemos pensar que factores tales como el suelo y la topografía son fijos, en el espacio y en el tiempo, sin embargo las plantas del cultivo de viñedo presentan microvariaciones locales con diversas respuestas adaptativas. En efecto, dentro de un mismo viñedo, aéreas aparentemente uniformes desde un punto de vista pedológico y topográfico presentan plantas con vigores vegetativos totalmente distintos, considerando todos los factores fijos. Estos micro – terroirs vegetativos proporcionan una diferenciación en la maduración de la uva, creando así una variación espacial y temporal en la calidad de la misma. Considerando los demás factores fijos y, partiendo del principio de que la variación espacial y temporal en el vigor vegetativo de una planta es un indicativo de su capacidad productiva, así como del potencial cualitativo del fruto, fueron controladas 80 hectáreas de viñedo mediante un sensor de vegetación. La base de datos, espacial y temporal, obtenida y posteriormente analizada por componentes principales, permitió elaborar zonas homogéneas de tratamiento que denominamos micro – terroirs. Como resultado, se encontró que existe una variabilidad espacial y temporal en las regiones aparentemente uniformes en términos pedológicos y topográficos, lo que sugiere una capacidad de adaptación genética que no siempre es fácil de tener en cuenta. La capacidad de monitorizar la variación espacial y temporal del vigor vegetativo de la vid, permitirá gestionar diferenciadamente las unidades geográficas distintas, desde el punto de vista de la calidad del vino