Proteínas desacopladoras (UCPs) estão presentes na membrana mitocondrial interna e por meio do transporte de prótons do espaço intermembranas para a matriz mitocondrial desacoplam a oxidação dos substratos da síntese de ATP, dissipando a energia do potencial de membrana e, conseqüentemente, diminuindo a produção de ATP pela cadeia respiratória mitocondrial. O aumento na expressão de UCP2 está relacionado com um risco diminuído de obesidade e risco aumentado de desenvolvimento de diabetes melito. O polimorfismo - 866G/A na região promotora do gene da UCP2 está associado a um aumento da expressão do RNAm desta proteína. O objetivo do presente estudo foi avaliar o envolvimento do polimorfismo -866G/A no gene UCP2 nas respostas metabólicas ao exercício e na taxa metabólica basal em jovens saudáveis. Foram recrutados 27 homens com idades entre 20 e 35 anos, sem histórico de doenças e sem uso de medicamentos, eutróficos e que não estivessem envolvidos em nenhum tipo de treinamento físico. Os indivíduos foram alocados intencionalmente em três diferentes grupos, de acordo com o genótipo para o polimorfismo em questão: A/A(n=9), A/G (n=10) e G/G (n=8). Todos os indivíduos foram submetidos a uma análise de taxa metabólica basal e após uma refeição padrão realizavam 30 minutos de corrida em esteira em intensidade equivalente a 10% abaixo do 2º limiar ventilatório. Em jejum, antes do exercício, logo após realização do exercício, uma hora após e duas horas após o exercício foram realizadas coletas de sangue para a verificação do comportamento das concentrações de glicose, insulina e perfil lipídico. Não foram encontradas diferenças entre as respostas dos três grupos. Este estudo concluiu que isoladamente o polimorfismo -866G/A não exerce influência sobre a TMB e respostas de glicose, insulina e perfil lipídico ao exercício em jovens saudáveis. / Uncoupling proteins (UCPs) are present in the inner mitochondrial membrane and through the transport of protons from the intermembrane space to the mitochondrial matrix to uncouple oxidation of substrates for ATP synthesis, dissipating the energy of the membrane potential and, consequently, decreasing the production of ATP by the mitochondrial respiratory chain. The increased expression of UCP2 is associated with a decreased risk of obesity and increased risk of developing diabetes mellitus. The polymorphism -866G/A in the promoter region of the UCP2 gene is associated with an increased mRNA expression of this protein. The aim of this study was to evaluate the involvement of the polymorphism -866G/A UCP2 gene in the metabolic responses to exercise and basal metabolic rate (BMR) in healthy young adults. We recruited 27 men aged between 20 and 35 years without history of disease and drug treatment, eutrophic and that were not involved in any type of physical training. The individuals were placed intentionally in three different groups according to genotype for the polymorphism related above: A/A (n=9), A/G (n=10) and G/G (n=8). All subjects underwent an analysis of BMR and after a standard meal performed 30 minutes of treadmill running at an intensity equivalent to 10% below the 2nd ventilatory threshold. Fasting, before exercise, immediately after exercise, after one hour and two hours after exercise, blood samples were collected to verify the behavior of glucose, insulin and lipid profile. No differences were found between the responses of the three groups. This study concluded that the polymorphism -866G/A in an isolated way does not influence BMR and responses of glucose, insulin and lipid profile over exercise in young healthy men.

Title: Basal metabolism and nutritional intervention for people with spinal cord injuries Objectives: The main objective of this work was empirical research of case evaluation studies (n = 3), where we analyzed: the relationship between energy expenditure (basal metabolism) and energy intake for people diagnosed with spinal cord injury (SCI). The secondary objective was to determine whether the changes in macronutrient distribution and daily energy intake would result in a decrease in body weight and body fat for individual probands. The pilot study in our work was focused on the overview of variable basal metabolism (BM) values for people with SCI. Methods: In our work, we used the method of indirect calorimetry to measure BM and together with the value of working metabolism we determined in the nutritional intervention (n. i.) the ideal energy intake for our probands. We observed primarily measurable changes in the amount of fat and muscle tissue. Results: We have found that, in keeping with the prescribed n. i. rules, all probands achieved to reduce their body weight. The average body weight loss for probands was 0.29 ± 0.02 kg per week. BM values in our pilot study were 15 to 61% lower for our probands (n = 15) and did not correlate with the height of SCI. Key words: spinal cord injury (SCI),...

Title: Basal metabolism and nutritional intervention for people with spinal cord injuries Objectives: The main objective of this work was empirical research of case evaluation studies (n = 3), where we analyzed: the relationship between energy expenditure (basal metabolism) and energy intake for people diagnosed with spinal cord injury (SCI). The secondary objective was to determine whether the changes in macronutrient distribution and daily energy intake would result in a decrease in body weight and body fat for individual probands. The pilot study in our work was focused on the overview of variable basal metabolism (BM) values for people with SCI. Methods: In our work, we used the method of indirect calorimetry to measure BM and together with the value of working metabolism we determined in the nutritional intervention (n. i.) the ideal energy intake for our probands. We observed primarily measurable changes in the amount of fat and muscle tissue. Results: We have found that, in keeping with the prescribed n. i. rules, all probands achieved to reduce their body weight. The average body weight loss for probands was 0.29 ± 0.02 kg per week. BM values in our pilot study were 15 to 61% lower for our probands (n = 15) and did not correlate with the height of SCI. Key words: spinal cord injury (SCI),...

High altitude is one of the most extreme environments experienced by terrestrial mammals due to both low ambient temperatures and oxygen availability. Deer mice native to high altitude have a greater thermogenic capacity in hypoxia compared to a lowland population, likely as a consequence of both genetic adaptations and phenotypic plasticity. To understand the adaptive variation in phenotypic plasticity, F1 generation lab-reared mice were acclimated to chronic warm-hypoxia, cold-normoxia, and cold-hypoxia. Acclimation led to equal increases in thermogenic capacity in hypoxia for all stressors in high altitude deer mice. Low altitude mice also increased their thermogenic capacity after acclimation, with a distinct increase after acclimation to cold-hypoxia. The thermogenic capabilities of the high and low altitude mice tested in hypoxia were equal, suggesting that both populations of mice had reached a “metabolic ceiling”. Basal metabolic rate increased after acclimation to cold and cold-hypoxia. Nonshivering thermogenesis was not affected by acclimation or altitude ancestry. Shivering thermogenesis contributed 70 to 80 % of total heat produced during VO2summit across all acclimations, and in both populations. VO2summit in hypoxia was supported by lipids in deer mice even though carbohydrates would provide an oxygen saving advantage. Also, rates of lipid oxidation increased after acclimation to cold, and cold combined with hypoxia in the high altitude population. Together these findings suggest that the increased thermogenic capacity of the high altitude wild mice is based both on differences in phenotypic plasticity, and on differences in genotype from the low altitude mice. Adult phenotypic plasticity is pivotal in the thermogenic capabilities of both populations, and it is likely that developmental plasticity also plays an important role. / Thesis / Master of Science (MSc)

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System dynamics can be a very useful tool to expand the boundaries of one's mental models to better understand the underlying behavior of systems. But despite its utility, there remains challenges associated with system dynamics modeling that the current research addresses by expanding the system dynamics modeling toolbox. The first challenge relates to imprecision or vagueness, for example, with respect to human perception and linguistic variables. The most common approach is to use table or graph functions to capture the inherent vagueness in these linguistic (qualitative) variables. Yet, combining two or more table functions may lead to further complexity and, moreover, increased difficulty when analyzing the resulting behavior. As part of this research, we extend the system dynamics toolbox by applying fuzzy logic. Then, we select a problem of congestion pricing in mitigating traffic congestion to verify the effectiveness of our integration of fuzzy logic into system dynamics modeling. Another challenge, in system dynamics modeling, is defining proper equations to predict variables based on numerous studies. In particular, we focus on published equations in models for energy balance and weight change of individuals. For these models there is a need to define a single robust prediction equation for Basal Metabolic Rate (BMR), which is an element of the energy expenditure of the body. In our approach, we perform an extensive literature review to explore the relationship between BMR and different factors including age, body composition, gender, and ethnicity. We find that there are many equations used to estimate BMR, especially for different demographic groups. Further, we find that these equations use different independent variables and, in a few cases, generate inconsistent conclusions. It follows then that selecting a single equation for BMI can be quite difficult for purposes of modeling in a systems dynamics context. Our approach involves conducting a meta-regression to summarize the available prediction equations and identifying the most appropriate model for predicting BMR for different sub-populations. The results of this research potentially could lead to more precise predictions of body weight and enhanced policy interventions to help mitigate serious health issues such as obesity. / Ph. D.

Objective: The aim of this study was to compare equations used to calculate BMR to values of BMR obtained from measurements in order to determine the most suitable equation to be used on children and adolescents with CF. Design: The participants where children and adolescents with CF. Data was collected from the division of Clinical Nutrition at Uppsala Akademiska Sjukhus. Age, weight, height, BMI, BMR, FFM and FM was recorded from 27 measurements. BMR from the participants collected from the indirect respiratory calorimetry was compared to the results obtained from five equations used to obtain a calculated value of BMR. Results: Tverskayas equation was best correlated with the measured BMR for the whole group. The equation underestimated BMR for the participants with a measured BMR over 1400 kcal/24h and overestimated BMR for participants with a measured BMR under 1400 kcal/24h. Similar results could be seen in the subgroups boys, girls and adolescents. Maffeis equation can be applied on the subgroup children. However, larger studies are needed to guarantee the results. Conclusion: It is desirable that an equation for calculating BMR would be developed that is specifically developed for children and adolescents with a low to normal BMI that takes into consideration a heightened metabolism and is therefore suitable for children and adolescents with CF. / Syfte: Att utifrån uppmätt BMR jämföra olika ekvationer för att hitta den mest lämpliga ekvationen för beräknandet av ett förutsätt värde av basalmetabolism hos en grupp barn och ungdomar med cystisk fibros. Metod: Deltagarna var barn och ungdomar med CF. Data till arbetet hämtades från enheten för klinisk nutrition vid Uppsala Akademiska sjukhus. Ålder, vikt, längd, BMI, BMR, FFM och FM samlades in från totalt 27 mättillfällen. Deltagarnas BMR, som uppmätts genom indirekta respiratorisk kalorimetri, jämfördes med fem ekvationer som räknar ut BMR utifrån olika antropometriska mått. Resultat: Tverskayas ekvation överensstämde bäst med uppmätt BMR i gruppen som helhet. Ekvationen underskattade dock BMR hos deltagare med ett BMR-behov över 1400 kcal/dygn och överskattade BMR hos deltagare med ett BMR-behov lägre än 1400 kcal/dygn. Liknande resultat sågs i undergrupperna pojkar, flickor och ungdomar. Maffeis ekvation skulle möjligen kunna tillämpas på gruppen barn, dock behöver större studier utföras för att kunna dra säkra slutsatser. Slutsats: Det vore önskvärt att det utvecklas en ekvation för BMR, särskilt utvecklad för barn och ungdomar med lågt till normalt BMI, som tar hänsyn till förhöjt BMR och som därmed lämpar sig särskilt för barn och ungdomar med CF.

Obesity is a growing problem globally. Currently 2.3 billion adults are overweight, and this number is rising. The most common method for weight loss is calorie counting, in which to lose weight a person should be in a calorie deficit. Basal Metabolic Rate accounts for the majority of calories a person burns in a day and it is therefore a major contributor to accurate calorie counting. This paper uses a Dynamic Bayesian Network to estimate Basal Metabolic Rate (BMR) for a sample of 219 individuals from all Body Mass Index (BMI) categories. The data was collected through the Lifesum app. A comparison of the estimated BMR values was made with the commonly used Harris Benedict equation, finding that food journaling is a sufficient method to estimate BMR. Next day weight prediction was also computed based on the estimated BMR. The results stated that the Harris Benedict equation produced more accurate predictions than the metabolic model proposed, therefore more work is necessary to find a model that accurately estimates BMR.

Background: Cerebral Palsy is usually divided into three subgroups: ataxic, spastic and dyskinetic, where children and adolescents can, because of misestimation in nutrition and energy intake, suffer from weight problems. Aim: To compare calculations with equations with the individual's measured RMR in the subgroups, to see if any equation is more suitable. This could be used as a tool to calculate the resting metabolism at times when it is not possible to perform clinical measurements. Method: The RMR has been measured in 37 children and adolescents aged 3-15 years through indirect respiratory calorimetry. Those values have been compared with calculations from five equations. The results were then analyzed in order to find if any equation is better to apply for calculating resting metabolism for each subgroup. Results: The ataxic group was overestimated by 56.5% of the calculated values. WHO/FAO/UNU’s equation indicates a significantly strong correlation between the measured and calculated values (r=0.85, p<0.05). The spastic group was underestimated by 53.3%. There is significance for all equations, however it is a relatively low correlation (r=0.63–0.66, p=0.02–0.03). The dyskinetic group was underestimated by 95%. There was no significant association between clinically measured values and the calculated resting metabolism (r=0.21–0.45, p=0.26–0.61). Conclusion: The equations are not reliable for calculation of energy need for all subgroups. There is a substantial risk of over- and underestimation, therefore awareness of the equations insufficiency is needed. Studies should be performed with additional basic data, and with more equations. Especially equations including further variables that involves the body composition. / Bakgrund: Cerebral Pares brukar delas in i undergrupper: ataktisk, spastisk och dyskinetisk, där barn och ungdomar kan, beroende på felskattningar av näringsintag och energiberäkning, lida av över- eller undervikt. Syfte: Att jämföra uträkningar med ekvationer med individernas uppmätta vilometabolism i de tre undergrupperna, för att se om någon ekvation lämpar sig bättre. Detta skulle kunna ge ett verktyg för att kunna räkna ut vilometabolismen vid de tillfällen då det inte är möjligt att utföra kliniska mätningar. Metod: Mätningar av vilometabolismen har utförts på 37 barn och ungdomar i åldern 3-15 år genom indirekt respiratorisk kalorimetri. Värdena har jämförts med uträkningar från fem ekvationer. Resultatet har sedan analyserats, för att hitta någon ekvation som är bättre lämpad för att räkna ut vilometabolismen, för respektive undergrupp. Resultat: Den ataktiska gruppen överskattades i 56,5% av uträkningarna av vilometabolism. WHO/FAO/UNUs ekvation påvisar ett signifikant starkt samband mellan det uppmätta och uträknade värdena (r=0,85, p<0,05). Den spastiska gruppen underskattades 53,3% av de uträknade värdena. Det föreligger signifikans för alla ekvationer, dock ett relativt lågt samband (r=0,63–0,66, p=0,02–0,03). Den dyskinetiska gruppen underskattades i 95 %. Det förelåg inget signifikant samband mellan kliniskt uppmätt och uträknad vilometabolism (r=0,21–0,45, p=0,26–0,61). Slutsats: Ekvationerna är inte tillförlitliga för uträkning av energibehov för alla undergrupper. Risk för över- och underskattning är överhängande, och en ökad medvetenhet om ekvationernas ofullständighet måste belysas. Studier bör göras med större underlag och med fler ekvationer. Framförallt ekvationer med fler variabler som tar hänsyn till kroppssammansättning.

Made available in DSpace on 2015-07-22T20:49:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-24 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Associação Fundo de Incentivo à Psicofarmacologia (AFIP) / Centros de Pesquisa, Inovação e Difusão (CEPID) / Durante o processo de envelhecimento ocorrem alterações neuroquímicas, morfológicas e funcionais, como a redução de algumas das características do sono, da quantidade da massa livre de gordura e da taxa metabólica basal. Estes fatores podem estar relacionados uma vez que a diminuição da taxa metabólica basal ocorre em conseqüência da diminuição da massa livre de gordura. O treinamento físico provavelmente pode minimizar tais efeitos e/ou trazer resultados positivos ao padrão do sono, assim como aos parâmetros da composição corporal e ao metabólico. O objetivo deste estudo foi avaliar os efeitos do treinamento resistido na taxa metabólica basal (TMB), na composição corporal e nos parâmetros do sono, verificando as suas possíveis relações em homens idosos. A amostra foi composta por 37 homens idosos com uma idade entre os 65 e os 75 anos, distribuídos aleatoriamente em dois grupos: o controle (GC) e o resistido (GR). O protocolo incluiu 72 sessões de treinamento resistido progressivo realizado três vezes semanais; e avaliações do metabolismo basal, da composição corporal, do sono (objetiva e subjetiva) e do consumo alimentar. Os resultados demonstraram que a força muscular aumentou em todos os grupos musculares no GR. Nas variáveis morfológicas, somente o GC aumentou a massa gorda e diminuiu a livre de gordura na avaliação final, enquanto que o GR manteve todas as variáveis da composição corporal. A TMB e o consumo energético diário não sofreram alterações em ambos os grupos ao longo das avaliações. Nas variáveis do sono, o GC aumentou o tempo total de sono, os microdespertares e o valor da escala de Pittsburgh, enquanto que o GR reduziu significativamente o percentual do estágio 1 do sono NREM. Houve associação de causa e efeito da massa livre de gordura (kg) e do estágio 1 sobre a TMB com o modelo final de regressão (TMB= 539,81 + 21,99 massa livre de gordura – 26,01 estágio 1), o que explica os 34% da variação da TMB. Em conclusão, os resultados sugeriram que o treinamento resistido, apesar de não alterar as relações entre a TMB, o sono e a composição corporal, foi efetivo para aumentar a força muscular, manter a massa livre de gordura e a TMB, e ainda melhorar a qualidade do sono em idosos saudáveis, refletindo numa qualidade de vida mais ativa para uma longevidade saudável. / During the process of aging, neurochemical, morphological and functional changes occur such as the decline of some characteristics of sleep, the amount of fat free mass and basal metabolic rate. These factors may possibly be related because the decrease in basal metabolic rate is due to the decrease in fat free mass. Physical training can possibly minimize such effects and / or bring positive results to sleep pattern, body composition and metabolism. The objective of this study was to evaluate the effects of resistance training on basal metabolic rate (BMR), body composition and parameters of sleep and to verify their possible relationship in elderly men. The sample consisted of 37 elderly men age 65 to 75 years randomly assigned into two groups: control (CG) and resisted (RG). The protocol included 72 sessions of progressive resistance training performed three times weekly, the evaluation of basal metabolism, body composition, sleep (objective and subjective) and food consumption. The results showed that muscle strength increased in all muscle groups in the RG. In the morphological variables, only the CG had the fat mass increased and decreased fat free mass in the final evaluation, in the other hand the RG remained with the same variables of body composition. The BMR and daily energy consumption remained unchanged in both groups during the evaluations. As far as sleep variables are concerned, the CG increased total sleep time, arousals and score of the scale of Pittsburgh, while the RG significantly reduced the percentage of stage 1 of NREM sleep. There was a chance association of the fat free mass (kg) and stage 1 for the BMR with the final model of regression (BMR = 539.81 + 21.99 mass free of fat - 26.01 stage 1), explaining 34% change in BMR. In conclusion, the results suggest that resistance training, although not altering the relationships between BMR, the sleep and body composition was effective in increasing muscle strength, keep free of fat mass and BMR and to improve the quality of sleep in healthy elderly, reflecting a quality of life more active for a healthy longevity. / FAPESP: 06/05210-0 / CEPID: 98/14303-3 / TEDE / BV UNIFESP: Teses e dissertações