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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

IoMT-Based Accurate Stress Monitoring for Smart Healthcare

Rachakonda, Laavanya 05 1900 (has links)
This research proposes Stress-Lysis, iLog and SaYoPillow to automatically detect and monitor the stress levels of a person. To self manage psychological stress in the framework of smart healthcare, a deep learning based novel system (Stress-Lysis) is proposed in this dissertation. The learning system is trained such that it monitors stress levels in a person through human body temperature, rate of motion and sweat during physical activity. The proposed deep learning system has been trained with a total of 26,000 samples per dataset and demonstrates accuracy as high as 99.7%. The collected data are transmitted and stored in the cloud, which can help in real time monitoring of a person's stress levels, thereby reducing the risk of death and expensive treatments. The proposed system has the ability to produce results with an overall accuracy of 98.3% to 99.7%, is simple to implement and its cost is moderate. Chronic stress, uncontrolled or unmonitored food consumption, and obesity are intricately connected, even involving certain neurological adaptations. In iLog we propose a system which can not only monitor but also create awareness for the user of how much food is too much. iLog provides information on the emotional state of a person along with the classification of eating behaviors to Normal-Eating or Stress-Eating. This research proposes a deep learning model for edge computing platforms which can automatically detect, classify and quantify the objects in the plate of the user. Three different paradigms where the idea of iLog can be performed are explored in this research. Two different edge platforms have been implemented in iLog. The platforms include mobile, as it is widely used, and a single board computer which can easily be a part of network for executing experiments, with iLog Glasses being the main wearable. The iLog model has produced an overall accuracy of 98% with an average precision of 85.8%. Smart-Yoga Pillow (SaYoPillow) is envisioned as a device that may help in recognizing the importance of a good quality sleep to alleviate stress while establishing a measurable relationship between stress and sleeping habits. A system that analyzes the sleeping habits by continuously monitoring the physiological changes that occur during rapid eye movement (REM) and non-rapid eye movement (NREM) stages of sleep is proposed in the current work. In addition to the physiological parameter changes, factors such as sleep duration, snoring range, eye movement, and limb movements are also monitored. The SaYoPillow system is processed at the edge level with the storage being at the cloud. SaYoPillow has 96% accuracy which is close to other existing research works. This research can not only help in keeping an individual self-aware by providing immediate feedback to change the lifestyle of the person in order to lead a healthier life, but can also play a significant role in the state-of-the-art by allowing computing on the edge devices.
312

Etude du contrôle hédonique de la prise alimentaire par l'analyse des potentiels évoqués gustatifs / Study of hedonic control of food intake using gustatory evoked potentials

Jacquin-Piques, Agnès 13 October 2016 (has links)
Les techniques d’électrophysiologie chez les animaux et d’imagerie fonctionnelle chez l’Homme ont permis d’étudier le contrôle hédonique de la prise alimentaire. Ce contrôle hédonique n’a cependant jamais été exploré chez l’Homme par l’étude des potentiels évoqués gustatifs (PEG), de meilleure résolution temporelle que l’imagerie fonctionnelle. Le premier objectif de la thèse a été de mettre au point une technique fiable et reproductible de recueil des PEG, en regard des aires cérébrales gustatives, en réponse à une stimulation sapide. Le deuxième objectif a été d’étudier les variations des PEG en fonction de la valeur hédonique de la prise alimentaire. Le travail de thèse a permis de mettre au point l’enregistrement des PEG, réalisés chez plus de 100 jeunes sujets sains. Les comparaisons effectuées entre les enregistrements cérébraux obtenus en réponse à l’eau seule ou à l’huile de paraffine, solutions non palatables, et après stimulation par une solution sapide ont permis d’apporter des arguments forts en faveur de l’origine gustative des potentiels évoqués enregistrés. L’analyse des PEG a permis de mettre en évidence des modifications de l’activation cérébrale en fonction du plaisir alimentaire, traduites par des changements de latence ou d’amplitude des PEG. Plusieurs situations connues pour faire varier le plaisir alimentaire ont été étudiées : avant/après repas ; stimulation par des solutions sucrées d’intensités différentes ou de valeurs énergétiques différentes ; stimulation par des acides gras. Des PEG en réponse aux acides gras à longue chaine (acides linoléiques) ont été enregistrés par ce biais, renforçant l’hypothèse du «gras» en tant que sixième saveur primaire. / Hedonic control of food intake has been studied using neurophysiological investigations in animals and functional imaging in humans. Gustatory evoked potentials (GEPs), a higher time resolution technique than functional imaging, have never been used for this purpose. The first aim of this thesis was to establish a reliable recording of GEPs in humans, in response to a sapid stimulus. The second aim was to determine the GEPs modifications according to the hedonic value of food intake. GEPs recording was performed in response to an intermittent stimulation of a sapid solution in more than 100 young healthy subjects. The comparisons between cerebral recordings in response to water or paraffin oil, non palatable solutions, and in response to sapid solutions (sucrose, sodium chlorure and fatty acids) allow us to advance strong arguments for the gustative nature of the recorded evoked potentials. GEPs analysis underlined changes in cerebral activation according to the hedonic value of the stimulus. These changes in cerebral activation were highlighted by modifications of GEPs latency or amplitude. Several physiological situations, marked by different pleasantness of food stimulation, were studied: before/after food intake, stimulation by sweet solutions with different concentrations or different caloric contents, stimulation by fatty acids. Moreover, GEPs in response to long chain fatty acids (linoleic acids) were recorded, reinforcing the hypothesis that fatty acids could be the sixth primary flavor.
313

The short-and long-term impact of an incentives program on healthier eating: a quasi-experiment in school cafeterias in Brazil

Ferreira, Claudio Meilman 06 December 2016 (has links)
Submitted by Claudio Meilman Ferreira (claudio.meilman@gmail.com) on 2017-01-05T15:53:53Z No. of bitstreams: 1 Claudio_Ferreira - Dissertação_Final.pdf: 1435979 bytes, checksum: f28673c2b369335f45c63beb6e43c635 (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2017-01-06T13:51:55Z (GMT) No. of bitstreams: 1 Claudio_Ferreira - Dissertação_Final.pdf: 1435979 bytes, checksum: f28673c2b369335f45c63beb6e43c635 (MD5) / Made available in DSpace on 2017-01-17T12:18:01Z (GMT). No. of bitstreams: 1 Claudio_Ferreira - Dissertação_Final.pdf: 1435979 bytes, checksum: f28673c2b369335f45c63beb6e43c635 (MD5) Previous issue date: 2016-12-06 / The impact of economic incentives on healthier eating is unclear, particularly in the long-term (i.e., after the intervention period). This research assessed the short- and long-term effectiveness of a private nutrition company’s promotion initiative in school cafeterias in Belo Horizonte, Brazil. Two hundred and eight children and adolescents from 3 schools participated in a short-lived, lottery-based incentives program contingent on the purchase of locally promoted healthy products. One hundred and forty-four children and adolescents from a fourth comparable school served as controls. A multilevel model compared the average number of promoted healthy products purchased daily per participant before (26 weekdays), during (9 weekdays), and after (28 weekdays) the intervention period. The results indicate a clear short-term effect. The incentives program significantly increased the purchase of promoted healthy products during (vs. before) the intervention period in the treated schools, specially among girls and younger children. On average, no long-term effect was observed. The purchase of the promoted healthy products returned to pre-intervention levels immediately after the removal of the incentives program. Interestingly, a detailed analysis revealed a rather heterogeneous long-term effect based on past consumption behavior. The incentive promoted a positive long-term effect on the children who had never consumed the incentivized healthier products prior to the intervention, whereas a negative long-term effect was noted for the already habitual consumers of the targeted healthier products. Past consumption behavior must be taken into consideration for a complete understanding of the long-term effects of incentives on healthier eating. / O impacto de incentivos econômicos sobre a alimentação saudável não é claro, particularmente no longo prazo (ou seja, após o período da intervenção). Esta pesquisa avaliou a eficácia de curto e longo prazo de uma iniciativa de promoção de uma empresa de nutrição privada em cantinas escolares em Belo Horizonte, Brasil. Duzentas e oito crianças e adolescentes de três escolas participaram de um programa de incentivos de curta duração baseado em um sorteio, condicionado à compra de produtos saudáveis promovidos localmente. Cento e quarenta e quatro crianças e adolescentes de uma quarta escola comparável serviram como controles. Um modelo multinível comparou o número médio de produtos saudáveis promovidos adquiridos diariamente por participante antes (26 dias úteis), durante (9 dias úteis) e após (28 dias úteis) o período da intervenção. Os resultados indicam um efeito claro de curto prazo. O programa de incentivos aumentou significativamente a compra de produtos saudáveis promovidos durante o período da intervenção (vs. antes) nas escolas tratadas, especialmente entre as meninas e crianças mais novas. Em média, nenhum efeito de longo prazo foi observado. A compra dos produtos saudáveis promovidos retornou aos níveis pré-intervenção imediatamente após a remoção do programa de incentivos. Curiosamente, uma análise detalhada revelou um efeito bastante heterogêneo de longo prazo baseado no comportamento prévio de consumo dos indivíduos. O incentivo promoveu um efeito positivo de longo prazo sobre as crianças que nunca haviam consumido os produtos promovidos e saudáveis antes da intervenção, ao passo que um efeito negativo de longo prazo foi observado para os consumidores já habituais dos produtos mais saudáveis visados. O comportamento do consumo passado deve ser levado em consideração para uma melhor compreensão dos efeitos de longo prazo de incentivos sobre uma alimentação mais saudável.
314

Caracteriza??o da neofobia alimentar em crian?as de tr?s a seis anos

Medeiros, Rodrigo Tavares Pinheiro de 23 January 2008 (has links)
Made available in DSpace on 2014-12-17T15:36:52Z (GMT). No. of bitstreams: 1 RodrigoTPM.pdf: 546581 bytes, checksum: cb4f6e4119e4c8484b61656898e881ae (MD5) Previous issue date: 2008-01-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Alimentation is essential in life. Concerning omnivores, characterized by the necessity of a varied diet to satisfy their metabolic needs, it is extremely advantageous the assumption of new foods. However, the assumption of new unknown foods is, potentially dangerous, because of possible intoxications. In this sense, one of the most important behaviors related to reducing risks is the so called food neophobia, characterized by the rejection of new foods and/or an ingestion of very little amounts. The aim of the present study was to investigate if age, sex and socio-economical status were able to influence food neophobia. The neophobia has been described in a range of 3-6 years old children taken both from public and private schools within the city of Natal-RN. Four different type of ice-creams, each one characterized by a different flavor, have been utilized. Two flavors were known to the young and the remaining two flavor were new. We didn't find significant differences between the investigated variables. However, the exploitation of data from the survey conducted showed that the ease or not to accept new foods obtained, was correlated with the variables under the same guidelines observed in literature. Aspects related to the stimulus used probably eased the neophobic answer. Then, it is suggested that the food neophobia can be influenced by sex, age and socioeconomic factors of individuaIs. Neophobia tends to be more common in girls, with ages between three to four years old and with a low leveI socioeconomic. In this sense, given the importance of kid neophobic reaction to the development of dietary patterns of other life's stages, it is necessary to make further studies to better explain this phenomenon. Given the pivotal role of food neophobia to the development of alimentary habits within all ages of life, other studies will be necessary for a better comprehension of such phenomena. Key-words: food neophobia; Evolutionary Psychology;children food intake; diet restriction; children's diet development / A alimenta??o ? essencial para a vida. Para os on?voros, que necessitam de uma dieta variada para conseguir suprir suas necessidades nutricionais, ? extremamente vantajoso incluir novos itens ? dieta. Contudo, ingerir alimentos desconhecidos pode ser perigoso, em raz?o da possibilidade de intoxica??o. Neste sentido, um dos comportamentos que auxiliam na redu??o dos riscos decorrentes da ingest?o de itens alimentares desconhecidos ? a neofobia alimentar, caracterizada pelo ato de recusar ou ingerir pequenas quantidades de um alimento novo. Este trabalho teve por objetivo investigar a influ?ncia da idade, do sexo e das caracter?sticas socioecon?micas dos indiv?duos na neofobia alimentar. Para isto, buscamos caracterizar o fen?meno neof?bico em crian?as de tr?s a seis anos de idade, oriundas de escolas p?blicas e particulares de Natal-RN. O alimento escolhido para o experimento foi sorvete, em quatro sabores distintos, sendo dois sabores conhecidos pelas crian?as e dois novos. Os resultados demonstraram n?o haver diferen?as em fun??o das vari?veis de sexo, idade e fatores socioecon?micos, quando avaliamos a escolha dos sabores do sorvete. Entretanto, a explora??o dos dados do question?rio realizado com os pais demonstrou que a facilidade ou n?o em aceitar novos alimentos obtida, se correlacionava com as vari?veis nas mesmas orienta??es observadas na literatura. Aspectos ligados ao alimento-est?mulo utilizado provavelmente atenuaram a resposta neof?bica. Com base neste ?ltimo dado, sugere-se que a neofobia alimentar pode ser prevista em fun??o de caracter?sticas de sexo, idade e fatores socioecon?micos dos indiv?duos, tendendo o fen?meno neof?bico a ser mais freq?ente em meninas, de tr?s a quatro anos e com um n?vel socioecon?mico mais baixo. Neste sentido, dada a import?ncia da rea??o neof?bica infantil para o desenvolvimento do padr?o alimentar das demais fases da vida, faz-se necess?ria a realiza??o de novos estudos para que possam a esclarecer melhor este fen?meno. Palavras-chave: neofobia alimentar, Psicologia Evolucionista; alimenta??o infantil; restri??o da dieta; forma??o da dieta infantil
315

Dietas hospitalares versus estado nutricional de pacientes internados em um hospital universitário

Melo, Fernanda Godoi 27 September 2013 (has links)
The high prevalence of hospital protein-energy malnutrition is associated with several factors, including implemented dietary conducts. Most hospitalized patients receive oral diets as their only source of nutrition. Study objectives were to evaluate the consumption of oral diets, the presence of reasons for not ingesting or incomplete food intake, and the evolution of the nutritional status of adult patients admitted to the Hospital de Clínicas, Universidade Federal de Uberlândia (HC-UFU). It was also objective of the study, analyze the general oral diet (GOD) served to inpatients in HC-UFU. The study was prospective, observational and descriptive for the inpatients, and prospective, descriptive, with semi-quantitative/qualitative approach for the food of the hospital GOD. Patients were included in the first 48 hours of hospitalization and maintained in follow-up throughout the period of hospital stay in the internal medicine ward. The supply, intake, minimum and adjusted energy needs (MEN; AEN) and minimum and adjusted protein needs (MPN; APN), and the reasons for not ingesting or incomplete food intake were assessed daily using the 24h Food Record form. The nutritional status of patients was assessed by anthropometric measurements (weight, height, body mass index) and Subjective Global Assessment (SGA). GOD was evaluated during 28 consecutive days, it was performed the weighing of each food served in the styrofoam lunch boxes of the lunch (n=3/day) and dinner (n=3/day) of the four implemented menus. The food options served in snacks (breakfast, afternoon snack and dinner) were not heavy because the portions are standard and known. Tables of nutritional composition were used to calculate the total energy value (TEV) and the energy distribution of macronutrients (percentage) of the food meals served daily, as well as to quantify the portions of foods from different food groups. Twenty-three patients who did not have a classification of malnutrition in the first 48 hours of hospitalization (SGA A) were included in the study, it corresponded to 204 days of follow-up. The supplied oral diets were sufficient to meet the AEN in 148 days (72.5%) and the APN in 80 days (39.2%). Dietary intake was insufficient to meet the AEN in 100 days (49%) and the APN in 156 days (76%). The mean intake of energy and/or protein was lower than the MEN and MPN for 7 patients (30.4%) and smaller than the AEN and APN for 21 patients (91.3%). A large number of reasons for not ingesting or incomplete food intake (n=1193) were reported, of which 1119 (93.8%) was present in food records of days in which food intake was below that adjusted need. The most common reasons were \"fasting\" (27.1%), \"lack of appetite\" (18.1%), \"satiety\" (13.4%) and \"sensory characteristics of food\" (9.1%). At the end of the follow-up period, one patient changed the classification of nutritional status of AGS A to AGS B, and 16 patients (69.6%) showed loss of body weight (-1.4±1.2kg). Negative associations were observed for \"difference between total energy intake and AEN\" and the number of \"reasons for not ingesting or incomplete food intake\" ( &#61554; =-0.7268; p-value<0.0000), and \"difference between the total amount of protein intake and APN\" and the number of \"reasons for not ingesting or incomplete food intake\" ( &#61554; =-0.8381; pvalue< 0.0000). And positive associations for \"difference between total energy intake and AEN\" and \"weight difference\" ( &#61554; =0.5034; p-value=0.0143), and \"difference between the total amount of protein intake and NPA\" and the number of \"weight difference\" ( &#61554; =0.6441; p-value=0.0009). In assessing the GOD, which presented TEV of the average offer of 2396.53±152.55 kcal/day, the mean energy distribution was adequate for protein (13.47%), carbohydrates (65.08%) and lipids (22%). Variable energy supply (percentage of TEV) was identified at breakfast (15.57%-20.61%), lunch (26.19%-36.59%), dinner (22.21%-31.06%), afternoon snack and supper (8.41%-15.50%). The period of overnight fasting was up to 13h. Regarding food groups, the supply was excessive for beans, meat/eggs, oils/fats/oilseed and sugar/sweets, and deficient for fruit/juices, legumes/vegetables, milk/derivatives. The supply of oral diets and the food intake of energy and protein were insufficient to meet the needs adjusted of considerable proportion of patients. The reasons that interfere the adequate food intake should be investigated and implemented measures to reduce them. It is essential to characterize the quantitative/qualitative aspects of GOD served to inpatients. Reducing the period of overnight fasting, as well as adjustments in the supply of food groups and in the food fractionation can contribute to better meet the nutritional needs and preventing the onset/worsening of nutritional deficiencies. / A alta prevalência da desnutrição proteico-energética hospitalar está associada a diversos fatores, incluindo condutas dietéticas implementadas. A maioria dos pacientes hospitalizados recebe dietas orais como única fonte de nutrição. Os objetivos do estudo foram avaliar o consumo de dietas orais, a presença de motivos para não ingestão ou ingestão incompleta de alimentos, e a evolução do estado nutricional de pacientes adultos internados no Hospital de Clínicas da Universidade Federal de Uberlândia (HC-UFU). Também foi objetivo do estudo, analisar a dieta geral oral (DGO) servida aos pacientes internados no HC-UFU. O estudo foi desenvolvido de forma prospectiva, observacional e descritiva em relação aos pacientes internados, e de forma prospectiva, descritiva, com abordagem semiquantitativa/ qualitativa para alimentos da DGO hospitalar. Os pacientes foram incluídos no estudo nas primeiras 48h de internação e mantidos em seguimento durante todo período de internação na enfermaria de Clínica Médica. A oferta, ingestão, necessidades mínimas e ajustadas de energia (NEM; NEA) e proteínas (NPM; NPA), e os motivos para não ingestão ou ingestão incompleta de alimentos, foram avaliados diariamente, utilizando formulário de Registro Alimentar de 24h. O estado nutricional dos pacientes foi avaliado por medidas antropométricas (peso, altura, índice de massa corporal) e Avaliação Global Subjetiva (AGS). A DGO foi avaliada durante 28 dias consecutivos, em que foi realizada pesagem de cada alimento servido nas marmitas do almoço (n=3/dia) e jantar (n=3/dia) dos quatro cardápios implementados. As opções alimentares servidas nos lanches (desjejum, lanche da tarde e ceia) não foram pesadas porque as porções são padronizadas e conhecidas. Tabelas de composição foram utilizadas para o cálculo do valor energético total (VET) e da distribuição energética percentual dos macronutrientes dos alimentos das refeições servidas diariamente, assim como, para quantificar as porções de alimentos dos diferentes grupos alimentares. Foram incluídos 23 pacientes que não apresentaram a classificação de desnutrição nas primeiras 48h de internação (AGS A), correspondendo a 204 dias de seguimento. As dietas orais ofertadas foram suficientes para suprir a NEA em 148 dias (72,5%) e a NPA em 80 dias (39,2%). A ingestão alimentar foi insuficiente para suprir a NEA em 100 dias (49%) e a NPA em 156 dias (76%). A ingestão média de energia e/ou proteína foi menor do que as NEM e NPM para 7 pacientes (30,4%) e menores do que as NEA e NPA para 21 pacientes (91,3%). Foram relatados 1193 motivos para não ingestão ou ingestão incompleta de alimentos, sendo 1119 (93,8%) presentes em registros alimentares de dias em que a ingestão alimentar foi inferior à necessidade ajustada. Os motivos mais frequentes foram jejum (27,1%), inapetência (18,1%), saciedade (13,4%) e características sensoriais dos alimentos (9,1%). Ao final do período de seguimento, um paciente mudou a classificação do estado nutricional de AGS A para AGS B, e 16 pacientes (69,6%) apresentaram perda de peso corporal (- 1,4±1,2kg). Foram observadas associações negativas para diferença entre quantidade total de energia ingerida e a NEA e o número de motivos para não ingestão ou ingestão incompleta de alimentos ( &#61554; =-0,7268; p-valor<0,0000), e para diferença entre quantidade total de proteína ingerida e a NPA e o número de motivos para não ingestão ou ingestão incompleta de alimentos ( &#61554; =-0,8381; pvalor< 0,0000). E associações positivas para diferença entre quantidade total de energia ingerida e a NEA e diferença de peso ( &#61554; =0,5034; p-valor=0,0143), e para diferença entre quantidade total de proteína ingerida e a NPA e o número de diferença de peso ( &#61554; =-0,6441; p-valor=0,0009). Na avaliação da DGO, que apresentou VET da oferta média de 2396,53±152,55 kcal/dia, a distribuição energética média foi adequada para proteínas (13,47%), carboidratos (65,08%) e lipídios (22%). Oferta energética variável (porcentagem do VET) foi identificada no desjejum (15,57%-20,61%), almoço (26,19%-36,59%), jantar (22,21%-31,06%), lanche da tarde e ceia (8,41%-15,50%). O período de jejum noturno foi de até 13h. Em relação aos grupos alimentares, a oferta foi excessiva para feijões, carnes/ovos, óleos/gorduras/oleaginosas e açúcares/doces e deficiente para frutas/sucos, legumes/verduras, leite/derivados. A oferta de dietas orais e ingestão alimentar de energia e proteínas foram insuficientes para atender as necessidades ajustadas de proporção considerável de pacientes. Os motivos que interferem a ingestão alimentar adequada devem ser investigados e implementadas medidas para reduzílos. É essencial realizar a caracterização quantitativa/qualitativa da DGO servida a pacientes hospitalizados. Redução do período de jejum noturno, assim como, adequações na oferta de grupos alimentares e no fracionamento alimentar podem contribuir para melhor atendimento das necessidades nutricionais e prevenção da instalação/agravamento de deficiências nutricionais. / Mestre em Ciências da Saúde
316

Relação de polimorfismos nos genes da perilipina 1, visfatina, resistina e grelina com a resposta a um programa de orientação nutricional para a redução de peso corporal / Relationship of polymorphisms in the perilipine 1, visfatin, resistin and ghrelin genes with the response to the nutritional orientation program for the reduction of body weight

Marina Aparecida dos Santos 01 September 2017 (has links)
A obesidade é causada pelo desequilíbrio entre a ingestão alimentar e o gasto energético corporal, com o armazenamento de energia na forma de gordura, no tecido adiposo. A obesidade causa alterações metabólicas, como resistência à insulina e dislipidemia, além de aumento de adipocinas e citocinas pró-inflamatórias. Este trabalho investigou a influência de polimorfismos nos genes da perilipina 1 (PLINl), visfatina (NAMPT) , resistina (RETN) e grelina (GHRL) na adiposidade e no perfil metabólico e inflamatório, antes e após um programa de orientação nutricional. Foram selecionados indivíduos obesos (OB, n=214), sobrepeso (SOB, n=71) e não obesos (NOB, n=69), com idade de 30 a 70 anos. Foram obtidos dados clínicos, antropométricos e de composição corporal. O recordatório de 24h foi aplicado a 87 indivíduos obesos para avaliação de consumo alimentar, antes e após o programa de orientação nutricional. Foi obtido sangue para extração de DNA e para analisar parâmetros laboratoriais (perfil lipídico e glicêmico, marcadores inflamatórios e adipocinas). Polimorfismos dos genes PLINl, NAMPT, RETN e GHRL foram analisados por PCR em tempo real. O grupo OB teve perfil antropométrico alterado e risco aumentado de hipertensão, diabetes tipo 2 e dislipidemia em comparação com os grupos SOB e NOB (p<0,05). As concentrações de glicose, colesterol total, LDL colesterol, VLDL colesterol, triglicérides, apolipoproteína B (ApoB), interleucina 1&#946; (IL-l &#946;) e fator de necrose tumoral alfa (TNF&#945;) foram maiores e as concentrações de HDL colesterol e apolipoproteina AI (apoAI) foram menores, no grupo OB que nos outros grupos (p<0,05). As frequências dos polimorfismos genéticos do grupo total foram similares as de outras populações. Os polimorfismos NAMPT rs1319501 C>T e rs10763861 C>T foram associados com obesidade (p<0,05). Os polimorfismos genéticos não influenciaram o perfil antropométrico do grupo total (p>0,05), mas no grupo de obesos, o polimorfismo GHRL rs4684677 T>A foi relacionado com maior porcentagem de gordura corporal (p=0,043). Após a orientação nutricional, observou-se diminuição da ingestão de calorias e do consumo de carboidratos, gorduras totais, sódio, magnésio e betacaroteno (p<0,05). Os polimorfismos genéticos não influenciaram o perfil antropométrico e o consumo alimentar de obesos, após a orientação nutricional. Em conclusão, polimorfismos dos genes NAMPT e GHRL contribuem para a adiposidade, mas não influenciam o comportamento alimentar e o perfil antropométrico, após orientação nutricional. / Obesity is caused by the imbalance between food intake and body energy expenditure, with the storage of energy in the form of fat, in adipose tissue. Obesity causes metabolic changes, such as insulin resistance and dyslipidemia, and an increase in adipokines and pro-inflammatory cytokines. This work investigated the influence of polymorphisms in the perilipine 1 (PLINI) , visfatin (NAMPT) , resistin (RETN) and ghrelin (GHRL) genes on adiposity and metabolic and inflammatory profile, before and after a nutritional orientation programo Obese (OB, n=214), overweight (SOB, n=71) and nonobese subjects (NOB, n=69), aged 30 to 70 years, were selected. ClinicaI, anthropometric and body composition data were obtained. The 24-hour dietary recall was applied to 87 obese subjects to eva1uate food intake before and after the nutritiona1 orientation programo Blood was obtained for DNA extraction and to analyze 1aboratory parameters (lipid and glycemic profile, inflammatory markers and adipokines). Po1ymorphisms of the PLINI, NAMPT, RETN and GHRL genes were analyzed by real-time PCR. The OB group had altered anthropometric profile and increased risk for hypertension, type 2 diabetes and dyslipidemia in comparison with SOB and NOB groups (p <0.05). Concentrations of glucose, total cholesterol, LDL cholesterol, VLDL cholesterol, triglycerides, apolipoprotein B (ApoB), interleukin 1&#946; (IL-1&#946;) and tumor necrosis factor alpha (TNF&#945;) were higher and the concentrations ofHDL cholesterol and apolipoprotein AI (apoAI) were lower in the OB than in the other groups (p <0.05). The frequencies of the genetic polymorphisms of the total group were similar to those of other populations. NAMPT rs1319501 C> T and rs10763861 C> T polymorphisms were associated with obesity (p <0.05). Genetic polymorphisms did not influence the anthropometric profile ofthe total group (p> 0.05), but in the obese group, the GHRL rs4684677 T> A polymorphism was related to a higher body fat percentage (p = 0.043). After nutritional orientation, a decrease in calorie intake and in the consumption of carbohydrates, total fats, sodium, magnesium and beta-carotene CP <0.05) were observed. Genetic polymorphisms did not influence the anthropometric profile and the dietary intake of obese individuaIs after nutritional orientation. In conclusion, NAMPT and GHRL gene polymorphisms contribute to adiposity but do not influence dietary behavior and anthropometric profile after nutritional orientation.
317

Ciclos de atividade/repouso e alimentação/jejum associados ao uso de equipamentos eletrônicos: aspectos comportamentais e padrões temporais / Not informed by the author

Tatiana Harumi Seito 27 January 2017 (has links)
A energia elétrica de uso doméstico no cenário mundial é um fenômeno recente que incorporou modulações temporais na expressão dos ritmos biológicos, como os hábitos alimentares e de sono. Após sua popularização, tecnologias eletrônicas foram criadas e incorporadas às nossas rotinas diárias. O acesso à iluminação elétrica promove uma maior flexibilidade na organização temporal das nossas atividades por facilitar o controle de extensão da fase de atividade para horas mais tardias da noite. Assim, essa situação pode constituir um desafio temporal ao organismo, gerado pelas oscilações das pistas temporais, adiantando ou atrasando a ocorrência de eventos rítmicos como a alimentação/jejum, atividade/repouso e metabolismo. O estudo foi realizado com 27 universitários entre 18 a 30 anos (17 mulheres; 10 homens) nos quais o comportamento alimentar e de sono foi registrado por meio do uso de diários e os ciclos de atividade/repouso e claro/escuro por meio de actímetros. Observada uma associação indireta entre o uso de equipamentos eletrônicos e o aumento no consumo alimentar. A associação observada em relação ao uso dos equipamentos com a ingesta está mais amparada no atraso do início do sono que propicia o aumento observado da ingesta média na fase noturna. No longo prazo o atraso da fase do sono e a diminuição da sua duração pode gerar um desalinhamento na regulação da expressão dos padrões temporais de atividade/repouso e alimentação/jejum que pode alterar o padrão do comportamento alimentar / Electric energy used widely in domestic context is a recent phenomenon that incorporates temporal modulations on the expression of biological rhythms and behaviour, like food ingestion and sleep patterns. After popularization of electric energy, electronic technologies have been created and incorporated to our routines. Access to electric light can promote more flexibility on temporal organization of our activities which allow for an extension of the wake phase to later portions of the night. Thus, that situation could promote temporal challenges to the organisms, generated by oscillations of temporal signals, which may cause phase advances or delays in rhythmic events like feeding/fasting, rest/activity and metabolic functions. This study involved 27 university students between 18 to 30 years old (17 women; 10 men) where feeding and sleep behavior data were collected with feeding and sleep diaries; the rest/activity rhythm and the light/dark cycle data were collected with actimeters. The association observed in relation to the use of the electronic equipments with the food intake is supported by the delay of the beginning of rest that propitiates the increase of the average intake in the nocturnal phase. In the long term, the delay of the rest phase and the decrease of its duration can generate a misalignment in the regulation of the expression of the temporal patterns of rest/activity and feeding/fasting and thus change the temporal pattern of the feeding behavior
318

Avaliação da saúde bucal, dores orofaciais, disfunções mandibulares e saliva em pacientes com diagnóstico de transtornos alimentares / Evaluation of oral health, orofacial pain, mandibular dysfunction and saliva in patients with eating disorders

Samanta Pereira de Souza 15 September 2016 (has links)
INTRODUÇÃO: A Anorexia Nervosa (AN) e a Bulimia Nervosa (BN) destacam-se como os principais Transtornos Alimentares (TA). A presença de dor orofacial e de disfunção temporomandibular poderia desenvolver quadros de dores crônicas da face, podendo interferir no estado emocional, além de dificultar a ingesta alimentar - comprometendo ainda mais o estado nutricional desses pacientes. MÉTODOS: Foram avaliados 64 pacientes distribuídos nos grupos: Grupo A (AN Restritiva): 07; Grupo B (AN Purgativa): 19; Grupo C (BN): 16; Grupo D (Grupo-controle): 22 pacientes. A avaliação foi realizada por meio da avaliação pela ficha clínica odontológica, questionário de xerostomia, índice de higiene oral, aplicação do Protocolo de Pesquisa para Dor Orofacial (Ficha EDOF-HC e questionário RDC/TMD - Versão em Português) e avaliação de diversos parâmetros salivares (fluxo salivar, pH, capacidade tampão, amilase, peroxidase, ácido siálico, proteína total, eletrólitos), da saliva estimulada e não estimulada, no Laboratório de Biologia Oral da Faculdade de Odontologia da USP. RESULTADOS: Pacientes com TA apresentaram diferenças significativas quanto ao CPOD (p=0,000) em relação ao grupo-controle, principalmente comparando-se os grupos purgativos com o controle (p < 0,05). Queixas como \"sangramento gengival\" (p=0,043) e sinais como erosão e perimólise (p < 0,001) e sensação de boca seca (p=0,000) foram mais prevalentes em pacientes com TA. A queixa de \"ardor bucal\" (p=0,005) foi relatada somente entre os pacientes que praticavam a autoindução de vômitos. A condição periodontal (p=0,02), e o índice de higiene oral (p < 0,001) mostraram-se mais satisfatórios nos indivíduos do grupo-controle. As queixas de dor na face foram mais prevalentes em pacientes com TA (p=0,004) em relação ao controle, porém, sem diferenças entre os grupos restritivos e purgativos (p=0,442). Os transtornos musculares (p=0,010) e alterações articulares patológicas (p=0,051) estão entre as principais alterações encontradas com a aplicação do questionário RDC/TMD. A higiene oral, os parâmetros salivares e o CPOD não têm relação com a presença de dor miofascial. As LCNC são mais prevalentes nos grupos A, B e C em relação ao grupo D (p=0,03). O fluxo salivar mostrou-se reduzido nos pacientes dos grupos A, B e C em relação ao grupo-controle, tanto na saliva não estimulada (p=0,000) quanto na estimulada (p=0,001). Em relação ao pH, não houve diferenças significativas na saliva não estimulada (p=0,374) e na estimulada (p=0,121). Os valores da capacidade tampão também foram diferentes na saliva não estimulada (p=0,002) e estimulada (p=0,000), sendo os valores superiores no grupo-controle. Na saliva não estimulada, a amilase estava aumentada no grupo C (p=0,000), o ácido siálico estava aumentado no grupo D (p=0,000) e o Na estava reduzido no grupo D (p=0,05). Na saliva estimulada, a amilase e o ácido siálico também estavam aumentados no grupo C (p=0,008 e p=0,006, respectivamente), porém, o Na estava aumentado no grupo D (p=0,010). CONCLUSÕES: Pacientes com TA apresentam condição bucal (dentária e periodontal) pior em relação a indivíduos saudáveis, maior prevalência de sinais de erosão, de perimólise e de LCNC, bem como, maior número de queixas de sensação de boca seca, ardor bucal e de sangramento gengival, e pior índice de higiene oral e maior prevalência de queixas de dor orofacial em relação aos indivíduos saudáveis. O fluxo salivar é reduzido e há alterações na capacidade tampão, amilase, ácido siálico e sódio presentes na saliva. A queixa de \"ausência dentária\" é mais prevalente em pacientes com TA e com dor orofacial. A autoindução de vômitos, o índice CPOD e os parâmetros salivares não têm relação com a presença de dor miofascial / BACKGROUND: Anorexia Nervosa (AN) and Bulimia Nervosa (BN) stand out as the main eating disorders (ED). The presence of orofacial pain and temporomandibular dysfunction could develop frameworks of chronic pain of the face, which may interfere with emotional state, and hinder food intake - further compromising the nutritional status of these patients. METHODS: We evaluated 64 patients divided into two groups: Group A (AN Restrictive): 07; Group B (AN Purgative): 19; Group C (BN): 16; Group D (control group): 22 patients. The evaluation was conducted by evaluating the dental clinic record, xerostomia questionnaire, oral hygiene index, applying the research protocol for Orofacial Pain (EDOF-HC form and questionnaire RDC / TMD - Portuguese version) and evaluation of several salivary parameters (salivary flow, pH, buffering capacity, amylase, peroxidase, sialic acid, total protein, electrolytes), of the stimulated saliva and unstimulated in the Oral Biology Laboratory (School of Dentistry - USP) . RESULTS: Patients with ED showed significant differences in DMFT (p = 0.000) compared to the control group, especially comparing the purgative groups with the control (p < 0.05). Complaints such as \"gingival bleeding\" (p = 0.043) and signs such as erosion and perimólise (p < 0.001) and dry mouth (p = 0.000) were more prevalent in patients with ED. The complaint of \"burning mouth\" (p = 0.005) was reported only in patients who practiced self-inflicted vomiting. Periodontal status (p = 0.02) and the oral hygiene index (p < 0.001) were more satisfactory in the control group of individuals. Complaints of pain in the face were more prevalent in patients with ED (p = 0.004) compared to control, however, no differences between the restrictive and purgative groups (p = 0.442). Muscle disorders (p = 0.010) and pathological articular changes (p = 0.051) are among the major changes found with the application of the RDC / TMD questionnaire. The oral hygiene, salivary parameters and the DMF is not related to the presence of myofascial pain. The LCNC are more prevalent in groups A, B and C compared to group D, (p = 0.03). Salivary flow was shown to be reduced in patients in groups A, B and C in the control group, both in unstimulated saliva (p = 0.000) and the stimulated (p = 0.001). Regarding pH, no significant differences in the unstimulated saliva (p = 0.374) and stimulated (p = 0.121). The values of buffer capacity were also different in unstimulated saliva (p = 0.002) and stimulated (p = 0.000), with higher values in the control group. In unstimulated saliva amylase was increased in group C (p = 0.000), sialic acid was increased in D group (p = 0.000) and was reduced in the D group (p = 0.05). The stimulated saliva amylase and sialic acid were also increased in group C (p = 0.008 and p = 0.006, respectively), however, it was increased in group D (p = 0.010). CONCLUSIONS: Patients with ED present oral health (dental and periodontal) worse compared to healthy subjects, higher prevalence of signs of erosion of perimólise and LCNC as well as higher number of dry mouth complaints, oral burning and bleeding gingival, and worse index of oral hygiene and greater prevalence of orofacial pain complaints compared to healthy individuals. Salivary flow is reduced and there are changes in buffering capacity, amylase, sialic acid and sodium present in saliva. The complaint of \"dental absence\" is more prevalent in patients with ED and orofacial pain. The self-induction of vomiting, the DMFT index and salivary parameters unrelated to the presence of myofascial pain
319

Dieta habitual de adolescentes de uma escola estadual do município de São Paulo / The eating habits of adolescents in a state school in São Paulo

Graziela Mantoanelli 30 June 2003 (has links)
Introdução: O padrão alimentar, com alto teor de gordura, colesterol, açúcar refinado e o baixo teor de ácido graxos poliinsaturados e fibras presente na dieta dos adolescentes, é considerado o principal responsável pelo aumento da morbidade e mortalidade em adultos, pois resulta em aumento da prevalência de obesidade e conseqüentemente de doenças crônicas não transmissíveis. Objetivo: Avaliar a dieta habitual qualitativa e quantitativamente de adolescentes de ambos os sexos de uma Escola Estadual do Município de São Paulo - SP. Casuística e Métodos: Foram avaliados adolescentes de ambos os gêneros entre 14 e 18 anos e 11 meses de idade, em quatro momentos diferentes durante seis meses. Utilizou-se o Recordatório 24 horas para avaliar o consumo alimentar e os dados foram processados pelo software Virtual Nutri. As análises estatísticas (Kolmogorov-Smirnov, teste T Student bicaudal para amostras repetidas, Wilcoxon Signed Rank Test e McNemar) foram realizadas pelo SPSS 11.0. Resultados: O consumo de gordura total foi superior a 30% em todos os dias de análise; o consumo de fibras obteve uma tendência de melhora nos dias úteis, assim como a gordura insaturada; o alimento com consumo mais freqüente foi o arroz e o consumo dos salgados (pão de queijo, coxinha, esfiha, etc.) aumentou durante os dias da semana. O café da manhã teve um declínio de consumo durante o feriado. Conclusões: O conhecimento do da dieta habitual dos adolescentes possibilita o planejamento de políticas públicas de saúde voltadas à nutrição, orientações dietéticas específicas ao grupo e possíveis intervenções. / Introduction: High amounts of fat, cholesterol, refined sugar, and low amounts of fat acid and fibers present in the diets of adolescents is results in high rates of obesity, chronic non-communicable diseases, and death in adults. Objective: Evaluate qualitatively and quantitatively the daily eating habits of adolescent males and females from a São Paulo city state school. Methods: Students between the ages of 14 years and 18 years 11 months old in four different times in a six month period were evaluated. The students logged their food intake over a 24 hour period and the data was processed by the Virtual Nutri software. The statistical analysis (Kolmogorov-Smirnow, T Student test for two repeated samples, Wilcoxon Signed Tank Test, and McNemar) was made by SPSS 11.0. Results: For every day of the test, fat accounted for more than 30% of the caloric intake. The fiber intake showed a tendency to improve on week days when compared with weekends, as did the intake of unsaturated fats. The food most frequently consumed was rice. Snacks were consumed mostly on the holiday, and during holidays the students frequently skipped breakfast. Conclusions: This study of the eating habits of adolescents can help shape the public policies of health, nutrition, and diet for specific groups and interventions.
320

Rôle du récepteur cannabinoïde de type 1 sur des populations neuronales spécifiques dans la régulation de l'équilibre énergétique / Cell type-specific role of the type 1 Cannabinoid receptor in the regulation of energy balance

Bellocchio, Luigi 26 October 2010 (has links)
Le système endocannabinoïde (SEC) a récemment émergé comme un important modulateurde la prise alimentaire et de la balance énergétique. Les récepteurs cannabinoïdes de type 1(récepteurs CB1) et ses ligands endogènes, le 2-arachidonoyl-glycérol (2-AG) et l’anandamide(AEA), sont largement présents au sein du cerveau ainsi qu’au niveau des organespériphériques impliqués dans la régulation du métabolisme énergétique, tels que le foie, letissu adipeux, les muscles squelettiques, le pancréas et le tractus gastro-intestinal. Lastimulation pharmacologique des récepteurs CB1 conduit généralement à une augmentation dela prise et du stockage énergétique, tandis que les antagonistes CB1 exercent les effets opposéschez l’animal ainsi que chez l’homme. De surcroît, des corrélations ont été établies entre unesur régulation pathologique du SEC et les troubles métaboliques.Pourtant, plusieurs preuves indiquent que la relation entre le SEC et le métabolismeénergétique pourrait être plus complexe, probablement à cause de la multiplicité des sites oùle SEC peut agir à travers l’organisme. L’objectif général de ce travail de thèse fut dedisséquer les différents mécanismes par lesquels le SEC régule la prise alimentaire etl’équilibre énergétique. Le premier Chapitre de cette thèse détaille les mécanismes neuronauxmodulant l’équilibre énergétique chez les mammifères. Dans le Chapitre II, nous analysonsles différents types neuronaux cérébraux responsables de l’impact de la signalisation desrécepteurs CB1 sur la prise alimentaire stimulée. Dans le Chapitre III, nous proposons que leblocage pharmacologique des récepteurs CB1 exerce un effet anorexigène en agissant sur lesneurones périphériques sympathiques. Enfin, au cours du Chapitre IV nous disséquons le rôlepossible des récepteurs CB1 sur la balance énergétique.Les antagonistes CB1 ont été montrés comme n’exerçant que des effets anorexigènestransitoires, ceux-ci disparaissant après quelques semaines de traitement chez l’animal etquelques mois chez des patients obèses. De plus, les agonistes CB1 résultent en des effets biphasiques typiques. En effet, des doses faibles à modérées augmentent la prise alimentairechez l’animal tandis que de fortes doses diminuent les comportements d’ingestion. Lesrécepteurs CB1 sont exprimés sur différentes populations neuronales, dont les neuronesGABAergiques et glutamatergiques corticaux. Puisque l’activation des récepteurs CB1 induitgénéralement une réduction de la libération des neurotransmetteurs, il est probable que leseffets manifestement contradictoires des manipulations pharmacologiques soient dus à cetteexpression différentielle des récepteurs CB1. En combinant les approches pharmacologiqueset génétiques, nous avons montré que les récepteurs CB1 localisés au niveau du striatumventral sont associés à une action hypophagique via une inhibition de la transmissionGABAergique. Au contraire, les récepteurs CB1 cérébraux modulant les transmissionsexcitatrices sous-tendent l’effet orexigène bien connu des cannabinoïdes (Chapitre II).L’injection aiguë de l’antagoniste CB1, le SR141716 (Rimonabant) a un puissant effetanorexigène dans des conditions de prise alimentaire stimulée, telles que l’hyperphagieinduite par le jeûne. Néanmoins, la nature de cet effet (centrale versus périphérique) ainsi queles circuits neuronaux impliqués sont encore objets d’investigations. Dans le Chapitre III,nous mettons en évidence que l’hypophagie induite par le Rimonabant est indépendante d’unemodulation des transmissions GABAergique, glutamatergique corticale ou sérotoninergiquepar les récepteurs CB1 dans le cerveau, aussi bien que d’actions intrinsèques des récepteursCB1 au niveau de différents noyaux hypothalamiques. En fait, le Rimonabant inhibe la prisealimentaire stimulée en potentialisant directement l’activité du système périphériquesympathique.En ce qui concerne les fonctions métaboliques du SEC, il n’est actuellement pas encoreclairement établi si ce sont les récepteurs CB1 exprimés sur les neurones ou ceux localisés surles organes métaboliques périphériques qui jouent un rôle majeur dans le contrôle du stockageet de la consommation énergétique dans des conditions physiologiques ou pathologiques.Dans ce scenario, au Chapitre IV, nous montrons que les récepteurs CB1 neuronaux jouent unrôle clé dans le développement de l’obésité induite par la diète. Les souris mutantesconditionnelles caractérisées par une délétion des récepteurs CB1 au niveau des neurones duprosencéphale et des neurones périphériques sympathiques (connus pour contrôler la prisealimentaire et le poids corporel) mais pas au niveau des organes périphériques, exhibent unphénotype de type mince ainsi qu’une résistance à l’obésité induite par la diète. Ce phénotyperésulte d’une augmentation de l’oxydation des lipides et de la thermogenèse associée à unediminution de l’absorption énergétique due à une potentialisation de l’activité sympathique.Dans le Chapitre V, nous discutons de la signalisation neuronale des récepteurs CB1 commeune clé déterminante de l’action du SEC sur l’équilibre énergétique. Nous proposons que lesrécepteurs CB1 exercent un contrôle bimodal sur le comportement alimentaire et régulent lesdépenses énergétiques ainsi que l’activité du système nerveux sympathique. Les différencesentre le rôle des agonistes endogènes versus exogènes des récepteurs CB1, mais aussi entre lesagonistes versus antagonistes suggèrent que ces récepteurs pourraient bénéficier de propriétéspharmacologiques particulières à la signalisation du type cellulaire impliqué. / The endocannabinoid system (ECS) has recently emerged as an important modulator of foodintake and energy balance. Cannabinoid type-1 (CB1) receptor and endogenous ligands, 2-arachidonoyl-glycerol (2-AG) and anandamide (AEA), are largely present in the brain and inperipheral organs involved in the regulation of energy metabolism, such as liver, adiposetissue, skeletal muscle, pancreas and GI tract. Pharmacological CB1 stimulation generallyleads to an increase in energy intake and storage, whereas CB1 antagonists exert the oppositeeffects in both animals and humans. Furthermore, there is evidence of correlations betweenpathological ECS up-regulation and metabolic diseases.However, several pieces of evidence indicate that the relationship between the ECS andenergy intake and metabolism might be more complex than previously believed, likely due tothe different sites where the ECS could act in the body. The general aim of this Thesis workwas to dissect the different mechanisms through which the ECS regulates food intake andenergy balance. The first Chapter of this Thesis is an overview of the neuronal mechanismsregulating energy balance in mammals. In Chapter II, we analysed the brain neuronal typesresponsible of the impact of CB1 signalling on stimulated food intake. Chapter III, reveals thatthe pharmacological blockade of CB1 exerts anorectic effect acting at peripheral sympatheticneurons. Then (chapter IV) we dissected the possible impact of neuronal CB1 onto energybalance.CB1 antagonists were shown to exert only transient anorectic effects, which disappear afterfew weeks of treatment in animals and few months in obese patients. Furthermore, CB1agonists show typical biphasic effects, with low-to-moderate doses increasing food intake inanimals, and high doses decreasing ingestive behaviour. CB1 is expressed in many differentneuronal populations, including GABAergic and cortical glutamatergic neurons. As thegeneral effect of CB1 activation is a reduction of neurotransmitter release, it is possible thatthese apparently discrepant effects of pharmacological manipulations are due to thedifferential expression of the receptor. By using combined pharmacological and geneticapproaches we found that ventral striatal CB1 receptors are endowed with a hypophagicimpact through inhibition of GABAergic transmission. Conversely, brain CB1 receptorsmodulating excitatory transmission mediate the well-known orexigenic effects ofcannabinoids (Chapter II).The acute injection of CB1 antagonist SR141716 (Rimonabant) has an important anorecticeffect in condition of stimulated food intake, such as fasting-induced hyperphagia. However,the nature of this effect (central versus peripheral) as well as the neuronal circuits involved isstill matter of investigation. In Chapter III we show that rimonabant-induced hypophagia isindependent from CB1 modulation of GABAergic, cortical glutamatergic and serotoninergictransmission in the brain, as well as intrinsic actions of CB1 in different hypothalamic nuclei.In fact, rimonabant inhibits stimulated food intake by directly enhancing peripheralsympathetic actions.In relationship to metabolic functions of the ECS, it is not yet clear whether CB1 receptorsexpressed on neurons or on peripheral metabolic organs play a major role in the control ofenergy storage and consumption in both physiological and pathological conditions. In thisscenario, in Chapter IV, we show that neuronal CB1 receptors play a key role in thedevelopment of diet-induced obesity. Conditional mutant mice lacking CB1 expression inforebrain neurons and sympathetic peripheral neurons, known to control food intake and bodyweight, but not in peripheral organs, displayed a lean phenotype and resistance to diet-inducedobesity. This phenotype results from an increase in lipids oxidation and thermogenesis and adecrease in energy absorption due to an increase of the sympathetic tone.As discussed in the Chapter V, neuronal CB1 signalling is a key determinant of the ECSaction on energy balance, by exerting a bimodal control of feeding behaviour and byregulating energy expenditure and sympathetic nervous system activity. The differencesbetween the role of endogenous versus exogenous CB1 agonists, as well as between agonistsversus antagonists suggest that this receptor may have different pharmacological propertiesaccording to the cell type-specific signalling involved.

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