Download or read book Mathematical Modeling of the Hormonal Regulation of Food Intake and Body Weight written by Marine Jacquier and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The regulation of food intake and energy expenditure usually limits important loss or gain of body weight. Hormones (leptin, ghrelin, insulin) and nutrients (glucose, triglycerides) are among the main regulators of food intake. Leptin is also involved in leptin resistance, often associated with obesity and characterized by a reduced efficacy to regulate food intake. Mathematical models describing the dynamics of body weight have been used to assist clinical weight loss interventions or to study an experimentally inaccessible phenomenon, such as starvation experiments in humans. Modeling of the effect of hormones on body weight has however been largely ignored.In this thesis, we first consider a model of body weight regulation by hormones in rats, made of nonlinear differential equations. It describes the dynamics of food intake, body weight and energy expenditure, regulated by leptin, ghrelin and glucose. It is able to reproduce and predict the evolution of body weight and food intake in rats submitted to different patterns of caloric restriction, showing the importance of the adaptation of energy expenditure. Second, we introduce the first model of leptin resistance development, based on the regulation of food intake by leptin and leptin receptors. We show that healthy individuals may become leptin resistant and obese due to perturbations in food intake or leptin concentration. Finally, modifications of these models are presented, characterized by simplified yet realistic body weight dynamics. The models prove able to fit the previous, as well as new sets of experimental data and allow to build a complete model combining both previous models regulatory mechanisms.
Download or read book Mathematical modeling in energy homeostasis appetite control and food intake with a special attention to ghrelin written by Jorge Guerra Pires and published by Jorge Guerra Pires. This book was released on 2017-03-18 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: The elegant ‘interconnected mechanisms’ by which the gastrointestinal (GI) tract regulates food intake are a marvel of biology, but the redundancy (e.g., several hormones seem to have effects in food intake) of both GI (by means of hormones) and central nervous system (CNS, by means of satiety/satiation signals) pathways governing energy homeostasis poses formidable challenges for scientists trying to take a clear glimpse of this machinery, e.g. for designing anti-obesity and alike pharmaceuticals. In essence, notwithstanding the astonishing advancements made over the past few decades in unscrambling many of the molecular pathways involved in energy (homeostasis) regulation, a rather cloudy understanding of “how all the pieces fit together to function as an integrated system” is what can be found for the most part in the scientific community; we discuss that in part II of the work, in a single chapter divided in several sections for numerous imperative hormones, e.g. cholecystokinin. The current work is divided into three parts: part I is regarding fundamentals of physiology and mathematical modeling employed all over the work; part II is more generic and concerns several hormones (what we have called a “web of hormones”) and part III (divided into three chapters) is more specific, concerning a single hormone (i.e., ghrelin). The core of the work is part III, and to a certain extent part II, bearing mind we provide a literature review based on papers scattered/dispersed all over the medical science literature. The main objective of this work is proposing a mathematical model for ghrelin dynamics (Figure 70), a model centered on the gastrointestinal tract (stomach + small intestine, a two-compartment model), with daily-like dynamics, short-term dynamics; and, simultaneously, proposing a prototype for a systems biology like model (igure 40), a model based on numerous hormones, for understanding mathematically food intake/bodyweight control. Ghrelin is a quite powerful orexigenic hormone discovered in the late 1990s that controls appetite and energy homeostasis, alongside leptin and other hormones still to be investigated in depth by the medical sciences literature. Accordingly, we provide a (simple) mathematical model, consisting of a set of ordinary differential equations detailing ghrelin dynamics combined to gastrointestinal signals due to meals. Numerical simulations are able to replicate in silico available data from the literature; additionally, we were able to fit a reduced version of the basal model to experimental data. The model is developed as a module for a bigger potential multi-compartmental structure, detailing food and energy homeostasis within a sort of "a web of hormones" (see part II and the last chapter of part III). The present contribute is to recommend a primary mathematical model for ghrelin dynamics centered in the gastrointestinal tract, with potentiality to be applied also for postabsorptive states, left mainly as future works. We go on with the model by presenting mainly two variations, further unfolding is left as future endeavor: tastants and stochastic version. We test several optimization routines for the parameter estimation procedure, hybrid algorithms (global + local search), for parameter estimation, based on data published for humans (three meals a day). For all the routines, the best is a hybrid composed of simulating annealing as global search and pattern search as local search. In the objective function (sum of the squared errors, SSE), we apply artificial neural networks (a two-layer feedforward neural network) for generating new data from the data already published, a strategy adopted to increase the data set. In the last part of the chapter about ghrelin modeling (part III), we propose several prototypes for future works based on the basal models; the model used for parameter estimation is a “minimal/reduced” model; we also provide discussions and future works for the minimal model and parameter estimation. Key-words. Ghrelin; leptin; mathematical modelling; food intake; appetite; parameter estimation.
Download or read book Regulation of Body Weight written by Claude Bouchard and published by . This book was released on 1996-06-19 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fact that about 30-40% of the adults in the Western world are overweight or obese testifies to the frequency of the disturbances in body weight regulation. Scientists have established that caloric intake, macronutrient composition of the diet, basal and resting metabolic rate, thermic response to food, energy expenditure associated with movement and physical activity, and preferential storage of the surplus of calories as fat or lean tissues are critical determinants of energy balance and body weight. While much has been learned, the field is poised for major advances with the advent of a variety of imaging techniques, progress in quantitative and molecular genetics, use of transgenic rodent models and of breeding experiments with informative inbred strains, availability of stable isotopes for metabolic and behavioral studies, and a growing number of useful experimental animal and human models. This volume takes an integrative approach to obesity. It is structured around four major topics: (1) the animal and human models currently available for the study of body weight regulation with their strengths and limitations, (2) the molecular and genetic basis of the regulation of body weight, (3) the metabolic and physiological mechanisms involved, and (4) the behavioral and social determinants. The 13 background papers provide a critical overview of the present knowledge base while the group reports summarize the extensive deliberations of 38 international experts. Particular emphasis has been given to promising research areas and on the advances needed to ensure a better understanding of the biological and behavioral mechanisms of the regulation of body weight, with a particular emphasis on overweight and obesity.
Download or read book Research Awards Index written by and published by . This book was released on 1985 with total page 1588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Modeling in Experimental Nutrition written by Andrew J. Clifford and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrients have been recognized as essential for maximum growth, successful reproduction, and infection prevention since the 1940s; since that time, the lion's share of nutrient research has focused on defining their role in these processes. Around 1990, however, a major shift began in the way that researchers viewed some nutrients particularly the vitamins. This shift was motivated by the discovery that modest declines in vitamin nutritional status are associated with an increased risk of ill-health and disease (such as neural tube defects, heart disease, and cancer), especially in those populations or individuals who are genetically predisposed. In an effort to expand upon this new understanding of nutrient action, nutritionists are increasingly turning their focus to the mathematical modeling of nutrient kinetic data. The availability of suitably-tagged (isotope) nutrients (such as B-carotene, vitamin A, folate, among others), sensitive analytical methods to trace them in humans (mass spectrometry and accelerator mass spectrometry), and powerful software (capable of solving and manipulating differential equations efficiently and accurately), has allowed researchers to construct mathematical models aimed at characterizing the dynamic and kinetic behavior of key nutrients in vivo in humans at an unparalleled level of detail.
Download or read book Research Grants Index written by National Institutes of Health (U.S.). Division of Research Grants and published by . This book was released on 1975 with total page 1212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sport Nutrition for Health and Performance written by Melinda Manore and published by Human Kinetics. This book was released on 2009 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors sort fact from fiction to help students and practitioners of sports nutrition present sound advice to athletes on correct nutrition and dietary requirements.
Download or read book Mathematical Modelling in Animal Nutrition written by J. France and published by CABI. This book was released on 2008 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary purpose of each of the subsequent chapters of this book is to promulgate quantitative approaches concerned with elucidating mechanisms in a particular area of the nutrition of ruminants, pigs, poultry, fish or pets. Given the diverse scientific backgrounds of the contributors of each chapter (the chapters in the book are arranged according to subject area), the imposition of a rigid format for presenting mathematical material has been eschewed, though basic mathematical conventions are adhered to.
Download or read book Fat Detection written by Jean-Pierre Montmayeur and published by CRC Press. This book was released on 2009-09-14 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the State-of-the-Art in Fat Taste TransductionA bite of cheese, a few potato chips, a delectable piece of bacon - a small taste of high-fat foods often draws you back for more. But why are fatty foods so appealing? Why do we crave them? Fat Detection: Taste, Texture, and Post Ingestive Effects covers the many factors responsible for the se
Download or read book Federation Proceedings written by Federation of American Societies for Experimental Biology and published by . This book was released on 1984 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1942- include proceedings of the American Physiological Society.
Download or read book Appetite and Body Weight written by Tim Kirkham and published by Elsevier. This book was released on 2011-04-28 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is now enough basic work to sketch out the principal systems at all levels of the brain, from prefrontal cortex to lower brainstem, which are orchestrated to provide control of food selection, preference and consumption. At the same time, the complex interplay between central systems and signals generated from peripheral systems include the gut, liver and fat stores, as well as the interactions with the neuroendocrine system can be described in some detail. A continuing theme throughout the book is that the functional analysis of appetite and food intake cannot be limited to a single focus, e.g. hypothalamic neuropeptides and their interactions, but must be based on a fully integrated view of the several contributing systems. Appetite and Body Weight: Integrative Systems and the Development of Anti-Obesity Drugs provides an expert guide to the neural, neurochemical, autonomic and endocrine interrelations which underpin appetite and the controls of food intake and body weight. The book covers many of the neurochemical entities that are currently under investigation, including: neuropeptides, leptin, insulin, monoamines and endogenous cannabinoids in relation to appetite and body-weight control. In addition to the neuroscience analysis, there are also chapters that provide an expert guide to some of the key psychological concepts that the researchers believe are essential in trying to understand the phenomena under investigation. The volume will also serve as an authoritative guide to the current emphasis on the development of novel, efficacious anti-obesity medication. Provides an integrative view of the many systems involved in appetite how they interact to effect food intake (i.e. the brain, endocrine, gut, liver etc.) Considers psychological aspects such as incentive, preference, liking and palatability, and sets these concepts in their behavioural, pharmacological and neural contexts Examines the development of novel anti-obesity drugs, drawing on experience of pharmacological development work, pre-clinical tests for anti-obesity efficacy, and clinical trials of candidate anti-obesity compounds
Download or read book Nutrition in the Prevention and Treatment of Abdominal Obesity written by Ronald Ross Watson and published by Elsevier. This book was released on 2014-02-26 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrition in the Prevention and Treatment of Abdominal Obesity focuses on the important roles that exercise, dietary changes, and foods play in promoting as well as reducing visceral fat. Nutritionists, dieticians, and healthcare providers seeking to address the abdominal obesity epidemic will use this comprehensive resource as a tool in their long-term goal of preventing chronic diseases, especially heart, vascular, and diabetic diseases. Experts from a broad range of disciplines are involved in dealing with the consequences of excessive abdominal fat: cardiology, diabetes research, studies of lipids, endocrinology and metabolism, nutrition, obesity, and exercise physiology. They have contributed chapters that define a range of dietary approaches to reducing risk and associated chronic diseases. They begin by defining visceral obesity and its major outcomes; they also discuss the importance and the challenges of dietary approaches to reduce abdominal obesity, as compared to clinical approaches, with major costs and risks. Offers detailed, well-documented reviews outlining the various dietary approaches to visceral obesity with their benefits and failures Includes chapters on types of foods, exercise, and supplements in reducing obesity and its chronic clinical companions, especially diabetes and cardiovascular disease Helps nutritionists, dieticians, and healthcare providers approach patients in making decision about nutritional therapies and clinical treatments for abdominal obesity, from an evidence-based perspective
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1999 with total page 1846 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dietary Reference Intakes for Water Potassium Sodium Chloride and Sulfate written by Institute of Medicine and published by National Academies Press. This book was released on 2005-06-18 with total page 639 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate The Dietary Reference Intakes (DRIs) are quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people. This new report, the sixth in a series of reports presenting dietary reference values for the intakes of nutrients by Americans and Canadians, establishes nutrient recommendations on water, potassium, and salt for health maintenance and the reduction of chronic disease risk. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate discusses in detail the role of water, potassium, salt, chloride, and sulfate in human physiology and health. The major findings in this book include the establishment of Adequate Intakes for total water (drinking water, beverages, and food), potassium, sodium, and chloride and the establishment of Tolerable Upper Intake levels for sodium and chloride. The book makes research recommendations for information needed to advance the understanding of human requirements for water and electrolytes, as well as adverse effects associated with the intake of excessive amounts of water, sodium, chloride, potassium, and sulfate. This book will be an invaluable reference for nutritionists, nutrition researchers, and food manufacturers.
Download or read book Physical Fitness sports Medicine written by and published by . This book was released on 1984 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Consists of citations selected from those contained in the National Library of Medicine's Medical Literature Analysis and Retrieval System.
Download or read book Diet and Health written by National Research Council and published by National Academies Press. This book was released on 1989-01-01 with total page 765 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diet and Health examines the many complex issues concerning diet and its role in increasing or decreasing the risk of chronic disease. It proposes dietary recommendations for reducing the risk of the major diseases and causes of death today: atherosclerotic cardiovascular diseases (including heart attack and stroke), cancer, high blood pressure, obesity, osteoporosis, diabetes mellitus, liver disease, and dental caries.
Download or read book Cancer Prevention Fellowship Program written by and published by . This book was released on 2001 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
