Littérature scientifique sur le sujet « Metabolic circuitsk »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Sommaire
Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « Metabolic circuitsk ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Articles de revues sur le sujet "Metabolic circuitsk"
1
STERLING, PETER, et MICHAEL FREED. « How robust is a neural circuit ? » Visual Neuroscience 24, no 4 (juillet 2007) : 563–71. http://dx.doi.org/10.1017/s0952523807070526.
Texte intégralRésumé :
Design in engineering begins with the problem of robustness—by what factor should intrinsic capacity exceed normal demand? Here we consider robustness for a neural circuit that crosses the retina from cones to ganglion cells. The circuit's task is to represent the visual scene at many successive stages, each time by modulating a stream of stochastic events: photoisomerizations, then transmitter quanta, then spikes. At early stages, the event rates are high to achieve some critical signal-to-noise ratio and temporal bandwidth, which together set the information rate. Then neural circuits concentrate the information and repackage it, so that nearly the same total information can be represented by modulating far lower event rates. This is important for spiking because of its high metabolic cost. Considering various measurements at the outer and inner retina, we conclude that the “safety factors” are about 2–10, similar to other tissues.
2
Sun, Zhi, Weijia Wei, Mingyue Zhang, Wenjia Shi, Yeqing Zong, Yihua Chen, Xiaojing Yang, Bo Yu, Chao Tang et Chunbo Lou. « Synthetic robust perfect adaptation achieved by negative feedback coupling with linear weak positive feedback ». Nucleic Acids Research 50, no 4 (15 février 2022) : 2377–86. http://dx.doi.org/10.1093/nar/gkac066.
Texte intégralRésumé :
Abstract Unlike their natural counterparts, synthetic genetic circuits are usually fragile in the face of environmental perturbations and genetic mutations. Several theoretical robust genetic circuits have been designed, but their performance under real-world conditions has not yet been carefully evaluated. Here, we designed and synthesized a new robust perfect adaptation circuit composed of two-node negative feedback coupling with linear positive feedback on the buffer node. As a key feature, the linear positive feedback was fine-tuned to evaluate its necessity. We found that the desired function was robustly achieved when genetic parameters were varied by systematically perturbing all interacting parts within the topology, and the necessity of the completeness of the topological structures was evaluated by destroying key circuit features. Furthermore, different environmental perturbances were imposed onto the circuit by changing growth rates, carbon metabolic strategies and even chassis cells, and the designed perfect adaptation function was still achieved under all conditions. The successful design of a robust perfect adaptation circuit indicated that the top-down design strategy is capable of predictably guiding bottom-up engineering for robust genetic circuits. This robust adaptation circuit could be integrated as a motif into more complex circuits to robustly implement more sophisticated and critical biological functions.
3
Ni, Cynthia, Christina V. Dinh et Kristala L. J. Prather. « Dynamic Control of Metabolism ». Annual Review of Chemical and Biomolecular Engineering 12, no 1 (7 juin 2021) : 519–41. http://dx.doi.org/10.1146/annurev-chembioeng-091720-125738.
Texte intégralRésumé :
Metabolic engineering reprograms cells to synthesize value-added products. In doing so, endogenous genes are altered and heterologous genes can be introduced to achieve the necessary enzymatic reactions. Dynamic regulation of metabolic flux is a powerful control scheme to alleviate and overcome the competing cellular objectives that arise from the introduction of these production pathways. This review explores dynamic regulation strategies that have demonstrated significant production benefits by targeting the metabolic node corresponding to a specific challenge. We summarize the stimulus-responsive control circuits employed in these strategies that determine the criterion for actuating a dynamic response and then examine the points of control that couple the stimulus-responsive circuit to a shift in metabolic flux.
4
Oyarzún, Diego A., et Madalena Chaves. « Design of a bistable switch to control cellular uptake ». Journal of The Royal Society Interface 12, no 113 (décembre 2015) : 20150618. http://dx.doi.org/10.1098/rsif.2015.0618.
Texte intégralRésumé :
Bistable switches are widely used in synthetic biology to trigger cellular functions in response to environmental signals. All bistable switches developed so far, however, control the expression of target genes without access to other layers of the cellular machinery. Here, we propose a bistable switch to control the rate at which cells take up a metabolite from the environment. An uptake switch provides a new interface to command metabolic activity from the extracellular space and has great potential as a building block in more complex circuits that coordinate pathway activity across cell cultures, allocate metabolic tasks among different strains or require cell-to-cell communication with metabolic signals. Inspired by uptake systems found in nature, we propose to couple metabolite import and utilization with a genetic circuit under feedback regulation. Using mathematical models and analysis, we determined the circuit architectures that produce bistability and obtained their design space for bistability in terms of experimentally tuneable parameters. We found an activation–repression architecture to be the most robust switch because it displays bistability for the largest range of design parameters and requires little fine-tuning of the promoters' response curves. Our analytic results are based on on–off approximations of promoter activity and are in excellent qualitative agreement with simulations of more realistic models. With further analysis and simulation, we established conditions to maximize the parameter design space and to produce bimodal phenotypes via hysteresis and cell-to-cell variability. Our results highlight how mathematical analysis can drive the discovery of new circuits for synthetic biology, as the proposed circuit has all the hallmarks of a toggle switch and stands as a promising design to control metabolic phenotypes across cell cultures.
5
Sen, A. K. « Application of electrical analogues for control analysis of simple metabolic pathways ». Biochemical Journal 272, no 1 (15 novembre 1990) : 65–70. http://dx.doi.org/10.1042/bj2720065.
Texte intégralRésumé :
I have used electrical analogues for calculating the Flux Control Coefficients of metabolic pathways. An analogue circuit consists of resistances that are connected in series (or parallel) with a voltage (or current) source. In constructing the analogues, each of the enzymes in the pathway is associated with a resistance whose magnitude depends on the Elasticity Coefficients of the enzymes. These circuits can be designed in a heuristic fashion directly from the configuration of the pathway, without the necessity of writing down the governing equations with the use of Summation and Connectivity Theorems. The Flux Control Coefficients of the enzymes are represented by voltages across (or currents through) the resistances and are determined by an application of Ohm's Law. Results are given for (a) a simple linear pathway without feedback or feedforward regulation, and (b) a linear pathway with feedback inhibition. The analogue circuits are also convenient for assessing the relative importance of the various enzymes in flux control, and for simplifying the structure of a given pathway.
6
Oyarzún, Diego A., et Guy-Bart V. Stan. « Synthetic gene circuits for metabolic control : design trade-offs and constraints ». Journal of The Royal Society Interface 10, no 78 (6 janvier 2013) : 20120671. http://dx.doi.org/10.1098/rsif.2012.0671.
Texte intégralRésumé :
A grand challenge in synthetic biology is to push the design of biomolecular circuits from purely genetic constructs towards systems that interface different levels of the cellular machinery, including signalling networks and metabolic pathways. In this paper, we focus on a genetic circuit for feedback regulation of unbranched metabolic pathways. The objective of this feedback system is to dampen the effect of flux perturbations caused by changes in cellular demands or by engineered pathways consuming metabolic intermediates. We consider a mathematical model for a control circuit with an operon architecture, whereby the expression of all pathway enzymes is transcriptionally repressed by the metabolic product. We address the existence and stability of the steady state, the dynamic response of the network under perturbations, and their dependence on common tuneable knobs such as the promoter characteristic and ribosome binding site (RBS) strengths. Our analysis reveals trade-offs between the steady state of the enzymes and the intermediates, together with a separation principle between promoter and RBS design. We show that enzymatic saturation imposes limits on the parameter design space, which must be satisfied to prevent metabolite accumulation and guarantee the stability of the network. The use of promoters with a broad dynamic range and a small leaky expression enlarges the design space. Simulation results with realistic parameter values also suggest that the control circuit can effectively upregulate enzyme production to compensate flux perturbations.
7
Gao, Fei, Lijun Qi, Zhongzhen Yang, Tao Yang, Yan Zhang, Hui Xu et Huan Zhao. « Impaired GABA Neural Circuits Are Critical for Fragile X Syndrome ». Neural Plasticity 2018 (3 octobre 2018) : 1–7. http://dx.doi.org/10.1155/2018/8423420.
Texte intégralRésumé :
Fragile X syndrome (FXS) is an inheritable neuropsychological disease caused by silence of the fmr1 gene and the deficiency of Fragile X mental retardation protein (FMRP). Patients present neuronal alterations that lead to severe intellectual disability and altered sleep rhythms. However, the neural circuit mechanisms underlying FXS remain unclear. Previous studies have suggested that metabolic glutamate and gamma-aminobutyric acid (GABA) receptors/circuits are two counter-balanced factors involved in FXS pathophysiology. More and more studies demonstrated that attenuated GABAergic circuits in the absence of FMRP are critical for abnormal progression of FXS. Here, we reviewed the changes of GABA neural circuits that were attributed to intellectual-deficient FXS, from several aspects including deregulated GABA metabolism, decreased expressions of GABA receptor subunits, and impaired GABAergic neural circuits. Furthermore, the activities of GABA neural circuits are modulated by circadian rhythm of FMRP metabolism and reviewed the abnormal condition of FXS mice or patients.
8
Heath, Vicky. « Altered neuronal circuits control metabolic fate ». Nature Reviews Endocrinology 10, no 4 (11 février 2014) : 190. http://dx.doi.org/10.1038/nrendo.2014.14.
Texte intégral
9
Narayanan, Nandakumar S., Douglas J. Guarnieri et Ralph J. DiLeone. « Metabolic hormones, dopamine circuits, and feeding ». Frontiers in Neuroendocrinology 31, no 1 (janvier 2010) : 104–12. http://dx.doi.org/10.1016/j.yfrne.2009.10.004.
Texte intégral
10
Kim, Do-Yeon, Inmoo Rhee et Jihye Paik. « Metabolic circuits in neural stem cells ». Cellular and Molecular Life Sciences 71, no 21 (19 juillet 2014) : 4221–41. http://dx.doi.org/10.1007/s00018-014-1686-0.
Texte intégralThèses sur le sujet "Metabolic circuitsk"
1
Pandi, Amir. « Synthetic Metabolic Circuits for Bioproduction, Biosensing and Biocomputation ». Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS331.
Texte intégralRésumé :
La biologie synthétique est le domaine de la bioingénierie permettant de concevoir, de construire et de tester de nouveaux systèmes biologiques en réécrire le code génétique. Les circuits biologiques synthétiques sont des outils sophistiqués permettant de construire des réseaux biologiques pour des applications médicales, industrielles et environnementales. Cette thèse de doctorat porte sur le développement de voies métaboliques synthétiques conçues à l'aide d'outils informatiques. Ces voies métaboliques sont intégrées à la couche de régulation transcriptionnelle pour développer des biocircuits pour la bioproduction, la biodétection et la biocalcul dans des systèmes cellulaires et acellulaires. Les résultats obtenus durant cette thèse de doctorat révèlent le nouveau potentiel des voies métaboliques dans l'établissement de biocircuits synthétiques. Le volet bioproduction-biodétection de la thèse vise à développer un nouveau biocapteur pour un sucre rare utilisé pour améliorer l'activité catalytique d’enzyme dans la cellule (in vivo). Ce biocapteur a ensuite été implémenté dans un système acellulaire (in vitro) pour découvrir et optimiser le comportement de biocapteurs à base de répresseurs. Une fois optimisé en système acellulaire, notre biocapteur a été utilisé pour surveiller la production enzymatique de sucre rare. Le développement de biocapteurs procaryotes acellulaires, qui reposent principalement sur des répresseurs, permet d'accélérer et de rendre plus efficace le cycle “design-build-test” dans le prototypage des voies métaboliques dans les systèmes acellulaires. L'application de la biodétection des circuits métaboliques pour le diagnostic est la mise en œuvre et l'optimisation des transducteurs métaboliques dans le système acellulaire. Les transducteurs sont des voies métaboliques composées d'au moins une enzyme catalysant un métabolite indétectable en un inducteur transcriptionnel, augmentant ainsi le nombre de petites molécules biologiquement détectables. En tant que nouvelle approche pour effectuer des biocalculs, des circuits métaboliques ont été appliqués pour construire des additionneurs métaboliques et des perceptrons métaboliques. Dans la cellule, trois transducteurs métaboliques et un additionneur métabolique ont été construits et caractérisés. Les systèmes acellulaires permettent d’accélérer la caractérisation de circuits biologiques, de finement régler le niveau d’expression d’un ou plusieurs gènes et facilite l’expression de plusieurs plasmides simultanément. Ceci a permis de construire de multiples transducteurs pondérés et des additionneurs métaboliques. Le modèle basé sur des données expérimentales a permis de concevoir un perceptron métabolique pour construire des classificateurs binaires à quatre entrées. Les additionneurs, perceptrons et classificateurs peuvent être utilisés dans des applications avancées telles que la détection de précision et dans le développement de souches pour le génie métabolique ou la thérapeutique intelligenteSynthetic biology is the field of engineerable life science and technology to design-build-test novel biological systems through reprogramming the code of DNA. Synthetic biocircuits are sophisticated tools to reconstruct biological networks for medical, industrial, and environmental applications. This doctoral thesis focuses on the development of synthetic metabolic pathways designed by computer-aided tools integrated with the transcriptional regulatory layer enabling bioproduction, biosensing, and biocomputation in whole-cell and cell-free systems. The achievements of this doctoral thesis bring attention to new potentials of metabolic pathways in the development of synthetic biocircuits. The bioproduction-biosensing section of the thesis is to build a novel sensor for a rare sugar used to improve the catalytic activity of its producing enzyme in the whole-cell system (in vivo). This sensor was then implemented in a TX-TL cell-free system (in vitro) as a proof of concept of a repressor based biosensor to discover and optimize the behavior of repressor based biosensors in the cell-free system that suffer from low fold repression. The optimized cell-free biosensor was then used to monitor the enzymatic production of the rare sugar. The development of cell-free prokaryotic biosensors which are mostly relying on repressors enables faster and more efficient design-build-test cycle in metabolic pathways prototyping in cell-free systems. The biosensing application of the metabolic circuits for diagnosis is the implementation and optimization of cell-free metabolic transducers. The transducers are metabolic pathways composed of at least one enzyme catalyzing an undetectable metabolite to a transcriptional inducer, hence expanding the number of biologically detectable small molecules in cell-free systems. Finally, as a radical approach to perform biocomputation, metabolic circuits were applied to build metabolic adders and metabolic perceptrons. In whole-cell system, three metabolic transducers and a metabolic adder (multiple transducers receiving multiple input metabolites and transform them into a common metabolite) were built and characterized. By taking advantage of cell-free systems in rapid characterization, high tunability, and the possibility of using tightly controlled multiple DNA parts, multiple weighted transducers and metabolic adders were implemented. The integrated model trained on the experimental data enabled the designing of a metabolic perceptron for building four-input binary classifiers. The adders, perceptrons and classifiers can be applied in advanced applications such as multiplex detection/precision medicine and in the development of designer strains for metabolic engineering or smart therapeutics
2
Koch, Mathilde. « Computational modeling to design and analyze synthetic metabolic circuits ». Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS467/document.
Texte intégralRésumé :
Les buts de cette thèse sont doubles, et concernent les circuits métaboliques synthétiques, qui permettent de détecter des composants chimiques par transmission de signal et de faire du calcul en utilisant des enzymes. La première partie a consisté à développer des outils d’apprentissage actif et par renforcement pour améliorer la conception de circuits métaboliques et optimiser la biodétection et la bioproduction. Pour atteindre cet objectif, un nouvel algorithme (RetroPath3.0) fondé sur une recherche arborescente de Monte Carlo guidée par similarité est présenté. Cet algorithme, combiné à des règles de réaction apprises sur des données et des niveaux différents de promiscuité enzymatique, permet de focaliser l’exploration sur les composés et les chemins les plus prometteurs en bio-rétrosynthèse. Les chemins obtenus par rétrosynthèse peuvent être implémentés dans des cellules ou des systèmes acellulaires. Afin de concevoir le meilleur milieu pour optimiser la productivité du système, une méthode d’apprentissage actif qui explore efficacement l’espace combinatoire des composants du milieu a été développée.La deuxième partie a consisté à développer des méthodes d’analyse, pour générer des connaissances à partir de données biologiques, et modéliser les réponses de biocapteurs. Dans un premier temps, l’effet du nombre de copies de plasmides sur la sensibilité d’un biocapteur utilisant un facteur de transcription a été modélisé. Ensuite, en utilisant des systèmes acellulaires qui permettent un meilleur contrôle des variables expérimentales comme la concentration d’ADN, l’utilisation des ressources a été modélisée pour assurer que notre compréhension actuelle des phénomènes sous-jacents est suffisante pour rendre compte du comportement du circuit, en utilisant des modèles empiriques ou mécanistiques. Couplés aux outils de conception de circuits métaboliques, ces modèles ont ensuite permis de développer une nouvelle approche de calcul biologique, appelée perceptrons métaboliques.Dans l’ensemble, cette thèse présente des outils de conception et d’analyse pour les circuits métaboliques synthétiques. Ces outils ont été utilisés pour développer une nouvelle méthode permettant d’effectuer des calculs en biologie synthétiqueThe aims of this thesis are two-fold, and centered on synthetic metabolic circuits, which perform sensing and computation using enzymes.The first part consisted in developing reinforcement and active learning tools to improve the design of metabolic circuits and optimize biosensing and bioproduction. In order to do this, a novel algorithm (RetroPath3.0) based on similarity-guided Monte Carlo Tree Search to improve the exploration of the search space is presented. This algorithm, combined with data-derived reaction rules and varying levels of enzyme promiscuity, allows to focus exploration on the most promising compounds and pathways for bio-retrosynthesis. As retrosynthesis-based pathways can be implemented in whole cell or cell-free systems, an active learning method to efficiently explore the combinatorial space of components for rational media optimization was also developed, to design the best media maximizing cell-free productivity.The second part consisted in developing analysis tools, to generate knowledge from biological data and model biosensor response. First, the effect of plasmid copy number on sensitivity of a transcription-factor based biosensor was modeled. Then, using cell-free systems allowing for broader control over the experimental factors such as DNA concentration, resource usage was modeled to ensure our current knowledge of underlying phenomenons is sufficient to account for circuit behavior, using either empirical models or mechanistic models. Coupled with metabolic circuit design, those models allowed us to develop a new biocomputation approach, called metabolic perceptrons.Overall, this thesis presents tools to design and analyse synthetic metabolic circuits, which are a novel way to perform computation in synthetic biology
3
Audet, Diane. « Metabolic cost of aerobic dance circuit training ». Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56816.
Texte intégralRésumé :
This study was undertaken to characterize the oxygen consumption and heart rate responses of subjects during laboratory simulated aerobic dance circuit training sessions. Sixteen female subjects performed six randomly assigned 30-minute aerobic dance circuit training protocols. Oxygen consumption and heart rate responses were monitored in response to changes in three independent variables which were: interval duration, leg involvement and fitness level. Results revealed that the different interval durations generated significantly different oxygen costs. Also, it was found that in relative terms (% of max VO$ sb2$), the low fitness group (max VO$ sb2 $ 45 ml/kg.min). Furthermore, it was found that the involvement of deep knee bends during the resistance training segment of the circuit significantly increased the oxygen cost when the resistance training segments were compared. Finally, the results showed that exercise intensity was overestimated when using percentage of max HR.
4
Prudente, Paulo Adriano Naves. « Efeito do exercício combinado de intensidade moderada nos fatores de risco cardiometabólicos em mulheres com e sem síndrome metabólica ». Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6529.
Texte intégralRésumé :
Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2016-11-24T18:31:56Z
No. of bitstreams: 2
Dissertação - Paulo Adriano Naves Prudente - 2016.pdf: 2846301 bytes, checksum: dea8ae82bfe257d4d064620864e2d047 (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-11-28T17:48:09Z (GMT) No. of bitstreams: 2 Dissertação - Paulo Adriano Naves Prudente - 2016.pdf: 2846301 bytes, checksum: dea8ae82bfe257d4d064620864e2d047 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2016-11-28T17:48:09Z (GMT). No. of bitstreams: 2 Dissertação - Paulo Adriano Naves Prudente - 2016.pdf: 2846301 bytes, checksum: dea8ae82bfe257d4d064620864e2d047 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-11-03
Introduction: The phenomenon of metabolic syndrome (MS) is associated with a set of factors that constitute cardiometabolic risk, among them are the increase in abdominal fat, dyslipidemia, hyperglycemia and hypertension. Exercise can contribute to change the picture of the metabolic syndrome, however the type of exercise, the volume and intensity ideals are not yet fully established. Objective: Analyze the effects of 24 weeks of combined exercise on cardiometabolic risk factors in women with no metabolic syndrome. Methods: The study is not a randomized experimental trial and not controlled with the participation of 36 sedentary women, divided into two groups, one with metabolic syndrome (CSM, n = 22) and one without (SSM, n = 14). Sociodemographic data were collected at the beginning. Anthropometric and cardiometabolic risk factors evaluations were performed before and after the exercises. The diagnosis of metabolic syndrome was based on IDF parameters. For the assessment of cardiometabolic risk were considered the following factors: waist circumference (WC), ratio waist / height (WHtR), systolic blood pressure (SBP) and diastolic (DBP), HDL-C, triglycerides (TGL), blood glucose fasting, fasting insulin and HOMA-IR. The participants underwent 24 weeks of combined exercise (resistance circuit + aerobic) of moderate intensity, verified by the perceived exertion, and performed with the use of low-cost equipment. Statistical analyzes were performed to compare the difference of the average values of cardiometabolic risk factors before and after exercise. Results: Comparing the groups, the CSM showed a significant reduction of the values of body mass (p = 0.02), BMI (p = 0.02), SBP (p = 0.01), DBP (p <0.001), WHtR (p <0.001). The SSM group showed no statistically significant changes in any of the cardiometabolic risk factors after the practice of combined exercises. Conclusion: We conclude that the combined exercises resulted in significant reductions and clinically positive for SBP and DBP in the CSM group
Introdução: O fenômeno da síndrome metabólica (SM) está associado a um conjunto de fatores que constituem riscos cardiometabólicos, dentre eles estão o aumento de gordura abdominal, a dislipidemia, a hiperglicemia e a hipertensão arterial sistêmica. O exercício físico pode contribuir para alterar o quadro da síndrome metabólica, entretanto o tipo de exercício, o volume e a intensidade ideais ainda não estão claramente estabelecidos. Objetivo: Analisar os efeitos de 24 semanas de exercícios físicos combinados nos fatores de risco cardiometabólicos em mulheres com e sem síndrome metabólica. Métodos: O estudo é um estudo experimental não randomizado e não controlado com participação de 36 mulheres sedentárias, alocadas em dois grupos, um com síndrome metabólica (CSM, n=22) e outro sem (SSM, n=14). Dados sóciodemográficos foram coletados no início. As avaliações antropométricas e dos fatores de riscos cardiometabólicos foram realizadas antes e após a prática dos exercícios. O diagnóstico da síndrome metabólica foi realizado com base nos parâmetros da IDF. Para a avaliação do riscos cardiometabólicos consideraram-se os seguintes fatores: circunferência da cintura (CC), relação cintura/estatura (RCE), pressão arterial sistólica (PAS) e diastólica (PAD), HDL-c, triglicerídeos (TGL), glicemia de jejum, insulina em jejum e o HOMA-IR. As participantes foram submetidas à 24 semanas de exercício combinado (resistido em circuito + aeróbio) de intensidade moderada, verificada por meio da percepção subjetiva de esforço, e realizados com a utilização de equipamentos de baixo custo. Foram realizadas análises estatísticas para comparar a diferença dos valores médios dos fatores de riscos cardiometabólicos antes e após os exercícios. Resultados: Na comparação entre os grupos, o CSM apresentou redução significativa para os valores da massa corporal (p=0,02), IMC (p=0,02), PAS (p=0,01), PAD (p<0,001), RCE (p<0,001). O grupo SSM não apresentou alterações estatisticamente significativas em nenhum dos fatores de riscos cardiometabólicos após a prática de exercícios combinados. Conclusão: Concluímos que os exercícios combinados resultaram em reduções significativas e clinicamente positivas para a PAS e PAD no grupo CSM.
5
Farris, Gregory D. Kreider Richard B. « Analysis of exercise intensity and energy expenditure of women participating in the Curves exercise program ». Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4198.
Texte intégral
6
LÓPEZ, LUJÁN MARÍA DEL CARMEN. « Development of a mobile open-circuit system based on indirect calorimetry for energetic metabolism studies in small ruminants ». Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/50430.
Texte intégralRésumé :
[EN] For many years energy needs of ruminants have tried to be known to formulate rations adjusted, but it has been found that there are a variety of factors that affect them. Therefore, lots of studies are needed for evaluating the effect of these factors.
Consequently, the main objective of this Thesis was to design and validate a respirometry system based on indirect calorimetry, which would allow assessing energy needs of small ruminants accurately. It was intended from the beginning it was a mobile system and of relatively low cost. Furthermore, a methane gas analyzer was incorporated to this system, which allowed the measurement of emissions of this greenhouse gas and quantification of energy losses in the form of methane.
Initially the system had connected a mask, which was placed on the animal's face. A sample of exhaled gas was stored in a gas collection bag which was connected to the analyzer, and it measured the concentration of O2, CO2 and CH4 from the air. The proper functioning of the system was checked by a pilot experiment with dry Murciano-Granadina breed goats fed at maintenance level. Later this system was improved. Some of the most important changes were the replacement of the mask by a head hood in which the animal introduced the whole head, and the development of software that recorded and kept automatically concentrations of O2, CO2 and CH4 in exhaled air. This improvement allowed gas measurements during longer periods of time and recording more data. These changes were also validated through a pilot test with dry Manchega breed sheep.
Subsequently, three experiments were performed. One of them with dry Guirra ewes and the other two with Murciano-Granadina goats during mid lactation. Diets were mixed rations that differed in the inclusion of cereal or fibrous by-products. In these experiments the effect of diet was studied on digestibility, energy balance and carbon-nitrogen, oxidation of nutrients, rumen parameters and methane production; in the case of lactating goats, also on milk performance.
The determination of the calibration factor for O2 (1.005 ± 0.0101) confirmed the proper functioning of equipment. Moreover, small differences between the heat production obtained by indirect calorimetry and the carbon-nitrogen balance (2% in sheep and 1% in goats) demonstrated that this system allows determining the heat production of the animals reliably and accurately.
In the experiments of this Thesis have been estimated maintenance energy needs of two Spanish native sheep breeds, such as the sheep from the Guirra and Manchega breeds; net maintenance requirements were 270 kJ/kg BW0.75, on average. In the case of Murciano-Granadina breed goats, in the middle of lactation, the average utilization efficiency of metabolizable energy for lactation was 0.61.[ES] Desde hace años se ha tratado de conocer las necesidades energéticas de los rumiantes con el fin de formular raciones ajustadas, pero se ha comprobado que hay una gran variedad de factores que les afectan; por ello son necesarios estudios que evalúen el efecto de estos factores. Como consecuencia, el principal objetivo de esta tesis fue diseñar y validar un equipo de respirometría, basado en calorimetría indirecta, que permitiese evaluar las necesidades en energía de pequeños rumiantes de forma precisa. Se pretendió desde el inicio que fuese un sistema móvil y de relativo bajo coste. Además, a este sistema también se le incorporó un analizador de gas metano, que permitía la medición de las emisiones de este gas de efecto invernadero y la cuantificación de las pérdidas energéticas en forma de metano. Inicialmente el equipo tenía conectada una máscara que se colocaba en la cara del animal. Una muestra del gas espirado era almacenada en una bolsa de recogida de gases que era conectada al analizador, el cual medía la concentración de O2, CO2 y CH4 del aire. Se comprobó el correcto funcionamiento del sistema mediante una prueba piloto con cabras de raza Murciano-Granadina secas, alimentadas a nivel de mantenimiento. Posteriormente este sistema fue mejorado. Algunos de los cambios más importantes fueron la sustitución de la máscara por una urna en la que el animal introducía la cabeza entera, y el desarrollo de un software que registraba y guardaba de forma automática las concentraciones de O2, CO2 y CH4 del aire espirado. Esta mejora permitía medidas de gases durante periodos de tiempo más largos y el registro de muchos más datos. Estas modificaciones también fueron validadas mediante una prueba piloto con ovejas de raza Manchega secas. Posteriormente se realizaron tres experimentos. Uno de ellos con ovejas de raza Guirra secas y los otros dos con cabras Murciano-Granadinas en mitad de lactación. Las dietas fueron raciones mixtas que diferían en la inclusión de cereal o subproductos fibrosos. En estos experimentos se estudió el efecto de la dieta sobre la digestibilidad, balances de energía y carbono-nitrógeno, oxidación de los nutrientes, parámetros del rumen y producción de metano; en el caso de las cabras en lactación, también sobre los rendimientos productivos. La determinación del factor de calibrado para el O2 (1,005 ± 0,0101) confirmó el buen funcionamiento del equipo. Por otro lado, las pequeñas diferencias entre la producción de calor obtenida mediante calorimetría indirecta y el balance de carbono-nitrógeno (2% en ovejas y 1% en cabras) demostraron que este sistema permite determinar la producción de calor de los animales de forma fiable y precisa. En los trabajos de esta Tesis se han estimado las necesidades energéticas de mantenimiento en dos razas de ovejas autóctonas españolas, como son las razas Guirra y Manchega; las necesidades netas de mantenimiento fueron 270 kJ/kg PV0,75, de media. En el caso del ganado caprino de raza Murciano-Granadina, en mitad de lactación, la eficacia media de utilización de la energía metabolizable para la lactación fue de 0,61.
[CAT] Des de fa anys s'ha tractat de conèixer les necessitats energètiques dels remugants a fi de formular racions ajustades, però s'ha comprovat que hi ha una gran varietat de factors que els afecten; per això són necessaris estudis que avaluen l'efecte d'estos factors. Com a conseqüència, el principal objectiu d'aquesta Tesi va ser dissenyar i validar un equip de respirometría, basat en calorimetria indirecta, que permetera avaluar les necessitats en energia de menuts remugants de forma precisa. Es va pretendre des de l'inici que fóra un sistema mòbil i de relatiu baix cost. A més, a este sistema també se li va incorporar un analitzador de gas metà, que permetia el mesurament de les emissions d'este gas d'efecte hivernacle i la quantificació de les pèrdues energètiques en forma de metà. Inicialment l'equip tenia connectada una màscara que es col·locava en la cara de l'animal. Una mostra del gas expirat era emmagatzemada en una bossa d'arreplega de gasos que era connectada a l'analitzador, el qual mesurava la concentració d'O2, CO2 i CH4 de l'aire. Es va comprovar el funcionament correcte del sistema per mitjà d'una prova pilot amb cabres de raça Murciano-Granadina seques, alimentades a nivell de manteniment. Posteriorment este sistema va ser millorat. Alguns dels canvis més importants van ser la substitució de la màscara per una urna en què l'animal introduïa el cap sencera, i el desenrotllament d'un programari que registrava i guardava de forma automàtica les concentracions d'O2, CO2 i CH4 de l'aire expirat. Esta millora permetia mesures de gasos durant períodes de temps més llargs i el registre de moltes més dades. Estes modificacions també van ser validades per mitjà d'una prova pilot amb ovelles de raça Manxega seques. Després es van realitzar tres experiments. Un d'ells amb ovelles de raça Guirra seques i els altres dos amb cabres Murciano-Granadinas en mitat de lactació. Les dietes van ser racions mixtes que diferien en la inclusió de cereal o subproductes fibrosos. En estos experiments es va estudiar l'efecte de la dieta sobre la digestibilitat, balanços d'energia i carboni-nitrogen, oxidació dels nutrients, paràmetres del rumen i producció de metà; en el cas de les cabres en lactació, també sobre els rendiments productius. La determinació del factor de calibrat per a l'O2 (1,005 ± 0,0101) va confirmar el bon funcionament de l'equip. D'altra banda, les xicotetes diferències entre la producció de calor obtinguda per mitjà de calorimetria indirecta i el balanç de carboni-nitrogen (2% en ovelles i 1% en cabres) van demostrar que este sistema permet determinar la producció de calor dels animals de forma fiable i precisa. En els treballs d'esta Tesi s'han estimat les necessitats energètiques de manteniment en dos races d'ovelles autòctones espanyoles, com són les races Guirra i Manxega; les necessitats netes de manteniment van ser 270 kJ/kg PV0,75, de mitja. En el cas del bestiar caprí de raça Murciano-Granadina, en mitat de lactació, l'eficàcia mitjana d'utilització de l'energia metabolitzable per a la lactació va ser de 0,61.
López Luján, MDC. (2015). Development of a mobile open-circuit system based on indirect calorimetry for energetic metabolism studies in small ruminants [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/50430
TESIS
7
Fett, Carlos Alexandre. « "Avaliação metabólica nutricional de obesas no basal e após tratamento com dieta hipocalórica e treinamento em circuito ou caminhada" ». Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/17/17138/tde-20052005-093115/.
Texte intégralRésumé :
Propósito: Observar obesas pré e pós-dieta hipocalórica moderada, mais treinamento em circuito ou caminhada. quanto a variáveis nutricionais. Métodos: Grupos: treinamento em circuito, CIRC, n = 26, índice de massa corporal (IMC, kg/m2) = 33,2 ± 7,9 (Média±desvio padrão); idade = 32,6 ± 9,7 anos; e treinamento em caminhada, CAM, n = 24, IMC = 29,2±3,4; idade = 38,8 ± 10,5 anos. Avaliações: a composição corporal, coleta de urina e sangue, calorimetria indireta e testes físicos eram obtidos no inicio (M1) e final (M2) do estudo. Treinamento: mês 1 = 1 h x 3 d/semana; e mês 2 = 1 h x 4 d/semana. Dieta: foi adaptada do registro alimentar de uma semana, ajustado ao gasto energético de repouso (GER) e balanceada, com a seguinte proporção: 20% de proteínas; 20% de gorduras; e 60% de carbohidratos. Resultados: Pré-intervenção: 76% tinham algum familiar obeso; havia sintomatologia indicativa de: 60% ansiosas, 12% depressivas, 34% compulsivas e 32% distúrbio do sono, avaliadas por questionário no exame clínico. Foram encontrados níveis alterados de colesterol total (CT, mg/dL), e ou frações em 22% das sujeitas. O peso, IMC, o índice abdômem/quadril (IAQ), a soma de oito pregas cutâneas (SP8) se correlacionaram significativamente a quatro variáveis bioquímicas, e a circunferência do abdômen (CAb), e o percentual de gordura por antropometria (%GAntro) a cinco. Intervenção: O peso, IMC, %GAntro, endomorfia, massa gorda por bioimpedância (MGBia) e percentual de gordura por bioimpedância (%GBia), foram reduzidos significativamente nos dois grupos. O CIRC melhorou significativamente em todos (seis) e o CAM em três testes físicos. O CIRC teve significância para: ¯glicose (Gli), ¯AU, ¯CT, ¯Tg (todos em mg/dL), glóbulos vermelhos (GV) (mm3) e hematócrito (Ht) (%); e o CAM para: ¯Gli, ¯AU, ¯HDL, CT/HDL, GV, Ht. O GER não teve diferença em ambos os grupos. Conclusões: Pré-intervenção: Os dados antropometricos indicam boa correlação com os fatores bioquímicos de risco, mas não tem uma tendência constante. A taxa CT/HDL apresentou correlação com todas as medidas antropométircas e a Gli com nenhuma. A obesidade destas mulheres parece ter múltiplos fatores e o estilo de vida papel determinante. Intervenção: A atividade física per se foi importante para causar modificações nutricionais e da composição corporal nestas obesas. O CIRC teve melhor associação com o incremento da performance física e dados bioquímicos sanguineos e ambos os grupos preservaram o GER.Purpose: To observe obese women before and after a low-calorie diet plus circuit training or jogging regarding nutritional parameters. Methods: Groups: circuit training, CIRC, n = 26, body mass index (BMI, kg/m2) = 33.2 ± 7.9 (Mean±SD), age = 32.6 ± 9.7 years; and jogging training, JOGG, n = 24, BMI = 29.2 ± 3.4; age = 38.8 ± 10.5 years. Evaluations: body composition, collection of urine and blood samples, indirect calorimetry and physical tests were performed at the beginning (M1) and at the end (M2) of the study. Training: month one: 1 h x 3 d/week; month two: 1 h x 4 d/week. Diet: was adapted on the basis of a one week feeding record feed and adjusted to the resting metabolic rate (RMR) measured by indirect calorimetry, with the following proportion: 20% protein, 20% fat; and 60% carbohydrate. Results: Pre-intervention: 76% had one or more obese family members; there were symptoms indicating that 60% were anxious, 12% depressive, 34% compulsive, and 32% had sleep disorders, evaluated by a questionnaire during clinical examination. Altered levels of total cholesterol (TC) and/or fractions were found in 22% of the subjects. Weight (W), BMI, waist/hip ratio (WHR), and the sum of eight skin folds (8SF), were significantly correlated with four biochemistry variables, and abdominal circumference (AbC), and anthropometric fat percentage (%FAnthro) were correlated with five. Intervention: Weight, BMI, %FAnthro, endomorphy, body fat mass by bioimpedance (BFMBia) and percent body fat by bioimpedance (%FBia) were reduced in both groups. CIRC significantly increased performance in all (six) tests and the JOGG in three physical tests. CIRC showed significant differences for: ¯glucose (Glu), ¯UA, ¯TC (TC), ¯Tg (all in mg/dL), red blood cells (RBC) (mm3) and hematocrit (Ht) (%); and JOGG for: ¯Glu, ¯UA, ¯HDL, CT/HDL, RBC, Ht. The RMR was not significantly reduced in both groups. Conclusions: Pre-intervention: Anthropometric data indicated a good correlation with biochemical factors, but did not show a constant tendency. CT/HDL showed correlation with all anthropometric measurements and Glu with none. The obesity of these women appears to have multiple factors, with life style playing a determinant role. Intervention: Physical activities were determined to favor body composition, reduced weight and blood markers. CIRC were better in terms of physical performance and blood markers. Both types of training were sufficient to prevent a fall of RMR.
8
Lhomme, Tori. « La navette lactate tanycyte-neurone à POMC : un nouveau mécanisme de contrôle des circuits neuronaux de la prise alimentaire ». Thesis, Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUS056.
Texte intégralRésumé :
Les tanycytes du noyau arqué de l’hypothalamus (ARH) sont des cellules épendymogliales spécialisées se trouvant le long des parois du troisième ventricule (3V). Ils sont constitués d’un corps cellulaire polarisé dont la partie apicale entre en contact avec le liquide céphalo-rachidien (LCR) et dont la partie basale envoie un prolongement cytoplasmique vers les neurones du parenchyme nerveux. Leur localisation stratégique à l’interface entre le LCR contenant le glucose, et les neurones à pro-opiomélanocortine (POMC) répondant à des variations de glucose, renforce la possibilité que les tanycytes jouent un rôle important dans les mécanismes de détection hypothalamique du glucose, ainsi que dans le contrôle de la balance énergétique. Le but de ma thèse a été de tester l’hypothèse que les tanycytes de l’ARH formeraient un réseau métabolique de cellules interconnectées, au sein duquel le lactate, produit à partir du glucose circulant dans le LCR, diffuserait vers les neurones à POMC pour les alimenter en énergie, et les informer sur le statut glycémique de l’organisme afin de contrôler la balance énergétique. Les enregistrements électrophysiologiques ont indiqué qu’une majorité de neurones à POMC n’utilise pas le glucose, mais le lactate comme substrat énergétique pour soutenir leur activité électrique, via son métabolisme en pyruvate. Il a été montré que l’apport du lactate à ces neurones implique une navette fonctionnelle avec les tanycytes de l’ARH, dans laquelle ces derniers produisent le lactate à partir du glucose et le libèrent aux neurones à POMC via les transporteurs aux monocarboxylates (MCTs). De plus, les études ont démontré que la perturbation du réseau tanycytaire, formé par les connexines (Cxs) 43, conduit à une inhibition de l’activité électrique des neurones à POMC qui résulte d’un déficit de lactate dans l’ARH. De manière intéressante, il a été montré que le réseau tanycytaire contrôle la biodisponibilité du lactate dans cette région en réponse à des changements de taux circulants de glucose et régule le comportement alimentaire et le métabolisme énergétique chez les souris. Ces découvertes mettent en évidence un mécanisme utilisé par l’hypothalamus pour détecter les variations des taux circulants de glucose et pour maintenir la balance énergétiqueTanycytes of the arcuate nucleus of the hypothalamus (ARH) are specialized ependymoglial cells distributed along the lateral walls of the third ventricle (3V); their cell bodies contact the cerebrospinal fluid (CSF) while their processes arching in the tissue contact arcuate neurons. Their strategic location at the interface between the glucose-containing CSF and glucose-responsive proopiomelanocortin (POMC) neurons raises the possibility that tanycytes play a role in hypothalamic glucose detection mechanisms controlling energy balance. The aim of my thesis was to test the hypothesis that tanycytes convert glucose-containing CSF into lactate and distribute it to POMC neurons via a connexin 43 (Cx43)-mediated tanycytic metabolic networks, to control the energy balance. Electrophysiological recordings intriguingly indicated that most of the POMC neurons do not use glucose but lactate as energy substrate to sustain their electrical activity via its metabolism into pyruvate. The endogenous lactate required to sustain POMC neuronal activity is provided by ARH tanycytes via the conversion of glucose and shuttled to neurons via monocarboxylate transporters (MCTs). Furthermore, our study demonstrated that disruption of the Cx43-mediated tanycytic metabolic network leads to inhibition of POMC neuronal activity due to lactate deficiency into the ARH. These results thus show the importance of this network in the supply of lactate to POMC neurons. Finally, the tanycytic network was also shown to control the bioavailability of lactate in the ARH in response to changes in circulating glucose and to regulate feeding behavior and the energy metabolism in mice. Overall, our findings shed new lights on the mechanism used by the hypothalamus to monitor circulating levels of glucose and maintain of energy balance
9
Bouffard, Marc. « Conception, modélisation et simulation in silico d'un nanosystème biologique artificiel pour le diagnostic médical ». Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS302/document.
Texte intégralRésumé :
Le diagnostic médical, se fait traditionnellement, par l'examen des symptômes cliniques, puis en cherchant sur des prélèvements (sang, urine, biopsies, etc.) la présence (ou l'absence) simultanée des bio-marqueurs des diverses pathologies envisagées par le médecin. La recherche des bio-marqueurs se fait a l'aide d'équipements importants, dans un laboratoire d'analyse; les résultats étant communiqués au médecin, qui va les interpréter en appliquant un algorithme de diagnostic médical.Nous avons voulu regrouper dans un seul dispositif, pour une pathologie donnée, la détection des bio-marqueurs et une implémentation de l'algorithme de diagnostic approprié. La présence ou l'absence d'un bio-marqueur peut être représentée par une variable booléenne, et l'algorithme de diagnostic par une fonction booléenne complexe dont la valeur indiquera la présence de la pathologie ciblée.Notre dispositif de diagnostic sera un nano-calculateur biochimique artificiel dans lequel les informations logiques seront représentées par des métabolites et les calculs effectués par un réseau enzymatique synthétique. Pour réaliser ce calculateur, il a été nécessaire d'établir un fondement théorique des réseaux logiques enzymatiques. Nous avons ensuite utilisé cette théorie pour définir ce qu'est un circuit logique enzymatique et comment il calcule correctement la fonction booléenne associée. Pour des raisons de modularité et de réutilisabilité, nous avons décidé de concevoir des bibliothèques de portes logiques enzymatiques implémentant les opérateurs booléens de base, puis d'assembler ces briques de base pour obtenir le réseau enzymatique complet. J'ai donc conçu et développé deux outils logiciels, NetGate et NetBuild, qui vont réaliser automatiquement ces opérations.NetGate, qui va créer des bibliothèques contenant des centaines de portes logiques enzymatiques obtenues à partir de réseaux métaboliques d'organismes existants. Auparavant, il était nécessaire d'analyser manuellement ces réseaux métaboliques pour extraire chaque porte.NetBuild, qui va utiliser une bibliothèque de portes (par exemple créée par NetGate) et les assembler pour construire des circuits qui calculent une fonction booléenne donnée. Ces circuits utilisent comme entrées des métabolites spécifiques (par exemple: bio-marqueurs d'une pathologie) et produisent en sortie une espèce moléculaire facilement détectable (par colorimétrie par exemple)The medical diagnosis is traditionally done by examining the clinical symptoms and by searching in samples (blood, urine, biopsies, etc.) for the simultaneous presence (or absence) of biomarkers of the various pathologies considered by the doctor. The search for biomarkers is conducted using large equipments in a specialised laboratory; The results being communicated to the doctor, who will then interpret them by applying a medical diagnostic algorithm.We wanted to combine in a single device, for a given disease, the detection of its biomarkers and an implementation of the appropriate diagnostic algorithm. The presence or absence of a biomarker can be represented by a boolean variable, and the diagnostic algorithm by a complex boolean function whose value indicates the presence of the targeted disease. Our diagnostic device is an artificial biochemical nano-computer in which logical information is represented by metabolites and the computations performed by a synthetic enzymatic network. To build this computer, it has been necessary to establish a theoretical basis of enzymatic logical networks. We then used this theory to define what an enzymatic logic network is, and how it computes correctly the associated boolean function. For modularity and reusability reasons, we decided to design libraries of enzymatic logic gates that implement basic boolean operators, and then to assemble these building blocks to get the complete logic enzymatic network. So, I have designed and developed two software tools, NetGate and NetBuild, which will automatically perform these operations.NetGate creates libraries containing hundreds of enzymatic logic gates obtained from the metabolic networks of living organisms. Before that, it was necessary to manually analyse these metabolic networks in order to extract each logic gate.NetBuild uses a library of logic gates (for example created using NetGate) and assembles them to build circuits that compute a given boolean function. These circuits use specific metabolites for its inputs (for example the biomarkers of a pathology) and produce a readily detectable molecular species (using colorimetry for example)
10
Saucisse, Nicolas. « Dissection du rôle de la voie intracellulaire de mTORC1 dans les circuits hypothalamiques à la mélanocortine régulant la prise alimentaire ». Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0151/document.
Texte intégralRésumé :
L’hypothalamus est une structure cérébrale ayant un rôle clé dans la régulation de la prise alimentaire. Parmi les différentes populations neuronales qui le composent, les neurones produisant la pro-opiomélanocortine (POMC) sont classiquement connus pour diminuer la prise alimentaire et le poids corporel via la libération de neuropeptides produits par le clivage de POMC. Notre étude, grâce à l’utilisation d’approches génétiques, pharmacologiques, électrophysiologiques et moléculaires, remet en question les notions classiques sur la fonction des neurones à POMC dans la balance énergétique, en démontrant qu’il existe deux sous-populations fonctionnellement distinctes de neurones à POMC, qui augmentent ou diminuent la prise alimentaire en fonction du neurotransmetteur qu’elles libèrent, l’acide γ-aminobutyrique (GABA) ou le glutamate. Une troisième population capable de produire aussi bien du GABA que du glutamate a également été identifiée. La régulation des neurones à POMC GABAergiques et glutamatergiques dépend de la voie de la cible de la rapamycine chez les mammifères (mTORC1), qui fonctionne comme un détecteur d’énergie cellulaire, et du système endocannabinoïde (ECS), qui régule la libération de neurotransmetteurs. De plus, nous avons également démontré, via l’utilisation de souris mutantes conditionnelles, l’importance de la protéine p62 ou séquestrome 1 (p62/SQSTM1), qui régule l’activité de mTORC1 et l’autophagie, dans les neurones à POMC dans la régulation de l’homéostasie énergétique. Nos données offrent un nouvel aperçu sur les mécanismes moléculaires impliqués dans la régulation de la balance énergétiqueThe hypothalamus is a brain structure with a key role in the regulation of food intake. Among the different neuronal populations of which it is composed, pro-opiomelanocortin (POMC) neurons are classically known to decrease food intake and body weight through the release of neuropeptides produced by the cleavage of POMC. Our study, through the use of genetic, pharmacological, electrophysiological and molecular approaches, challenges conventional notions about POMC neuron function in energy balance by showing that there are two functionally distinct POMC neuronal sub-populations, which increase or decrease food intake depending on which neurotransmitter they release, γ-aminobutyric acid (GABA) or glutamate. A third population capable of producing both GABA and glutamate has also been identified. The regulation of POMC GABAergic and glutamatergic neurons depends on the mechanistic target of rapamycin complex 1 (mTORC1) pathway, which functions as a cellular energy sensor, and the endocannabinoid system (ECS), which regulates neurotransmitters release. In addition, we have also demonstrated through the use of a conditional knockout mice, the importance of the protein p62 or sequestrome 1 (p62/SQSTM1), which regulates mTORC1 activity and autophagy, in POMC neurons for the regulation of energy homeostasis. Our data provide new insights on the molecular mechanisms involved in the regulation of energy balance
Livres sur le sujet "Metabolic circuitsk"
1
Takao, Kumazawa, Kruger Lawrence et Mizumura Kazue, dir. The polymodal receptor : A gateway to pathological pain. Amsterdam : Elsevier, 1996.
Trouver le texte intégral
2
Rizza, Salvatore, Andrea Rasola, Danyelle M. Townsend et Giuseppe Filomeni, dir. Redox and Metabolic Circuits in Cancer. Frontiers Media SA, 2018. http://dx.doi.org/10.3389/978-2-88945-635-2.
Texte intégral
3
Nutt, David J., et Liam J. Nestor. Drug pharmacokinetics and abuse liability. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198797746.003.0005.
Texte intégralRésumé :
Pharmacokinetics refers to the effect of the body on drugs. Pharmacokinetics is divided into several areas including the extent and rate of absorption, distribution, metabolism, and excretion of substances. The rapid delivery of drugs like cocaine and nicotine, for example, enhances their effects in reward brain circuitry, and the rate at which the body can metabolize a substance may also make it more reinforcing. Pharmacokinetics, therefore, plays an important role in substance abuse and addiction and its treatment.
4
Reliability of cardiovascular and metabolic response to hydraulic resistive exercise. 1985.
Trouver le texte intégral
5
Reliability of cardiovascular and metabolic response to hydraulic resistive exercise. 1985.
Trouver le texte intégral
6
Reliability of cardiovascular and metabolic response to hydraulic resistive exercise. 1985.
Trouver le texte intégral
7
Goldstein, Jill M., L. Holsen, S. Cherkerzian, M. Misra et R. J. Handra. Neuroendocrine Mechanisms of Depression. Sous la direction de Dennis S. Charney, Eric J. Nestler, Pamela Sklar et Joseph D. Buxbaum. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190681425.003.0029.
Texte intégralRésumé :
Studies have demonstrated that major depressive disorder (MDD) is intimately tied to neuroendocrine dysregulation. This arises, in part, from the fact that brain regions that regulate mood also regulate primary neuroendocrine axes and metabolic functions. We and others demonstrated that the origin of MDD-neuroendocrine deficits begins in fetal development, is sex-dependent, emerges just post-puberty, and can be catalyzed by pregnancy (postpartum) and menopause. Here, we critically review clinical and preclinical studies to argue that higher MDD risk in women may arise, in part, from hormone-dependent pathogenic processes initiated during fetal development that drive sex-dependent developmental alterations of HPA circuitry emerging post-puberty with lifelong consequences.
8
Prescott, Tony J., Nathan Lepora et Paul F. M. J. Verschure, dir. Living machines. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199674923.001.0001.
Texte intégralRésumé :
Biomimetics is the development of novel technologies through the distillation of ideas from the study of biological systems. Biohybrids are formed through the combination of at least one biological component—an existing living system—and at least one artificial, newly engineered component. These two fields are united under the theme of Living Machines—the idea that we can construct artifacts that not only mimic life but also build on the same fundamental principles. The research described in this volume seeks to understand and emulate life’s ability to self-organize, metabolize, grow, and reproduce; to match the functions of living tissues and organs such as muscles, skin, eyes, ears, and neural circuits; to replicate cognitive and physical capacities such as perception, attention, locomotion, grasp, emotion, and consciousness; and to assemble all of these elements into integrated systems that can hold a technological mirror to life or that have the capacity to merge with it. We conclude with contributions from philosophers, ethicists, and futurists on the potential impacts of this remarkable research on society and on how we see ourselves.
9
Benarroch, Eduardo E. Neuroscience for Clinicians. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780190948894.001.0001.
Texte intégralRésumé :
The aim of this book is to provide the clinician with a comprehensive and clinical relevant survey of emerging concepts on the organization and function of the nervous system and neurologic disease mechanisms, at the molecular, cellular, and system levels. The content of is based on the review of information obtained from recent advances in genetic, molecular, and cell biology techniques; electrophysiological recordings; brain mapping; and mouse models, emphasizing the clinical and possible therapeutic implications. Many chapters of this book contain information that will be relevant not only to clinical neurologists but also to psychiatrists and physical therapists. The scope includes the mechanisms and abnormalities of DNA/RNA metabolism, proteostasis, vesicular biogenesis, and axonal transport and mechanisms of neurodegeneration; the role of the mitochondria in cell function and death mechanisms; ion channels, neurotransmission and mechanisms of channelopathies and synaptopathies; the functions of astrocytes, oligodendrocytes, and microglia and their involvement in disease; the local circuits and synaptic interactions at the level of the cerebral cortex, thalamus, basal ganglia, cerebellum, brainstem, and spinal cord transmission regulating sensory processing, behavioral state, and motor functions; the peripheral and central mechanisms of pain and homeostasis; and networks involved in emotion, memory, language, and executive function.
10
(Editor), T. Kumazawa, L. Kruger (Editor) et K. Mizumura (Editor), dir. The Polymodal Receptor - A Gateway to Pathological Pain (Progress in Brain Research). Elsevier Science, 1996.
Trouver le texte intégralChapitres de livres sur le sujet "Metabolic circuitsk"
1
Liao, James C. « Design of Synthetic Gene-Metabolic Circuits ». Dans Biologically Inspired Approaches to Advanced Information Technology, 1. Berlin, Heidelberg : Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11613022_1.
Texte intégral
2
Nasrallah, Carole M., et Tamas L. Horvath. « Mitochondria in Control of Hypothalamic Metabolic Circuits ». Dans The Functions, Disease-Related Dysfunctions, and Therapeutic Targeting of Neuronal Mitochondria, 186–202. Hoboken, NJ : John Wiley & Sons, Inc, 2015. http://dx.doi.org/10.1002/9781119017127.ch8.
Texte intégral
3
Yeo, Giles S. H. « Food Intake, Circuitry, and Energy Metabolism ». Dans Molecular Neuroendocrinology, 355–73. Chichester, UK : John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118760369.ch16.
Texte intégral
4
Patané, Andrea, Piero Conca, Giovanni Carapezza, Andrea Santoro, Jole Costanza et Giuseppe Nicosia. « Metabolic Circuit Design Automation by Multi-objective BioCAD ». Dans Lecture Notes in Computer Science, 30–44. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-51469-7_3.
Texte intégral
5
Friedman, M. J. « Leptin and the Neural Circuit Regulating body Weight and Metabolism ». Dans Research and Perspectives in Endocrine Interactions, 15–35. Berlin, Heidelberg : Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-642-18999-9_2.
Texte intégral
6
Wu, Qi, Yong Han et Qingchun Tong. « Current Genetic Techniques in Neural Circuit Control of Feeding and Energy Metabolism ». Dans Advances in Experimental Medicine and Biology, 211–33. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1286-1_12.
Texte intégral
7
Mohamad, Nur Ikhwan, Raiza Sham Hamezah et Ali Md Nadzalan. « Metabolic Cost of Continuous Body Weight Circuit Training with Aerobic-Based Exercise Interval for Muscle Strength and Endurance on Young Healthy Adults ». Dans Proceedings of the Second International Conference on the Future of ASEAN (ICoFA) 2017 – Volume 2, 737–46. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-8471-3_72.
Texte intégral
8
Rigillo, Marina. « Hybridizing Artifice and Nature : Designing New Soils Through the Eco-Systemic Approach ». Dans Regenerative Territories, 281–95. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-78536-9_18.
Texte intégralRésumé :
AbstractThe chapter outlines the cultural background for applying design strategies consistent with the challenge of circularity. The contribution focuses on ecological thinking as an effective design approach to produce and implement eco-innovative strategies able at facing environmental and societal challenges of our global age. Then the chapter depicts the Repair research experience in promoting a systemic design approach for recycling and reusing C&D waste as new, anthropogenic soils in peri-urban areas. According to the EEA Report n.6/2017, the chapter posits that the major environmental challenges of the present are not about single issues, such as waste reduction or soil-loss, rather they involve systemic change and design processes, linking together economy, social habits and technological responses. Therefore, the transition towards more sustainable urban metabolism deeply depends from creative visions by which breaking the circuit “take-make-dispose” and promote new—and somehow tentative—visions for implementing circularity at local and global scale. Further postulation in the paper is about assuming the concept of Anthropocene as theoretical ground for such eco-innovative design approach. The scientific evidence of living in human-dominated ecosystems makes designers towards a paradigm shift concerning the overcoming of the typical artificial/natural dichotomy by exploring the augmented opportunities in designing sustainable and resilient habitats thanks to a more collaborative, plural and innovative design approach: “What is important and significant here is how ecology and landscape architectural design might invent alternative forms of relationships between people, places and cosmos” (Corner, ‘Ecology and Landscape as agents of Creativity’, 1997, reprint in Reed &Lister (2018), Op. Cit., pp. 40–65, p. 42). Starting from these assumptions, the paper deepens the experience of collaborative design for implementing recycle and reuse of C&D waste for producing new technical soils, according to both the regulatory constraints (and potentials) and the site-specific features. The research goal is to provide new vegetated soils by waste thanks to an innovative design process based on both circular economy principles and collaborative knowledge production. Notably, the capacity of producing creative hybridization between biotic and abiotic component seems to be the new frontier in the field of technological design and material engineering. The term hypernatural, proposed by Blaine Brownell and Marc Swackhamer in 2015, introduces the idea of a co-evolutionary process between nature and science, looking at humans’ technological capacity as an effective opportunity for creating the conditions for making biotic ad abiotic systems working together: “The ultimate aim of technology is not antinatural: it is hypernatural” (Brownell & Swackhamer in Hyper-natural. Architecture’s new relationship with nature. Princeton Architectural Press, New York, p. 18, 2015). The chapter deals with the methodology applied for promoting a sort of protocological architecture (Burke, 2007), by which facilitating the C&D waste recycle and reuse within the construction sector, and notably into the landscape project. The research starts working under the H2020-Repair project, and it has developed within further research programs about C&D waste management in urban regeneration programs developed by the Department of Architecture of University of Naples Federico II.
9
Masgras, Ionica, et Andrea Rasola. « Metabolic Features of Neurofibromatosis Type 1-Associated Tumors ». Dans Neurofibromatosis [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98661.
Texte intégralRésumé :
Rewiring cellular metabolism is a key hallmark of cancer. Multiple evidences show that alterations in various metabolic circuits directly contribute to the tumorigenic process at different levels (e.g. cancer initiation, metastasis, resistance). However, the characterization of the metabolic profile of Neurofibromatosis type 1 (NF1)-related neoplastic cells has been only partially elucidated both in benign neurofibromas and in malignant peripheral nerve sheath tumors (MPNSTs). Here, we illustrate the state of the art on the knowledge of the metabolic features of tumors related to NF1 and discuss their potential implications for the development of novel therapeutic perspectives.
10
Chhabra, Seema, Smrity Sahu, Keshav Sharma, Maryada Sharma, Lekha Rani, Ranjana Minz et Sunil Dogra. « Th17/IL-17, Immunometabolism and Psoriatic Disease : A Pathological Trifecta ». Dans Psoriasis [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102633.
Texte intégralRésumé :
The burgeoning arena of immunometabolism provides evidence of how cellular, as well as local (tissue)/systemic metabolic pathways, are playing an important role in controlling immunity and inflammation. An intricate and elaborate network of various metabolic circuits specifically glycolysis, fatty acid oxidation and synthesis and amino acid metabolism precisely generate metabolites that rewire the immune response. Psoriasis is a chronic progressive self-perpetuated “IL-17-centric” inflammatory disease characterized by the co-existence of autoimmune and autoinflammatory pathways. Metabolic responses, governed by oxygen levels, nutrient availability, growth factors, cytokines, AMP/ATP ratios and amino acids, play a pivotal role in programming Th17 cell fate determination. Understanding the intricate interactions and complex interplay of molecular mechanisms responsible for Th17 cell metabolic rewiring, an important determinant of Th17 cell plasticity and heterogeneity, holds the potential to reshape psoriatic therapeutics in ways currently unimagined. This chapter entails with most recent updates on major cellular and systemic metabolic pathways regulating differentiation of Th17 cells as well their cross-talk with intracellular signaling mediators and also sheds light on how dysregulation of these pathways can be responsible for immune impairment and development of psoriatic disease. A better understanding of these metabolic processes could unveil an intriguing leverage point for therapeutic interventions to modulate metabolic programming and Th17 cell responses in this multi-systemic inflammatory disease.
Actes de conférences sur le sujet "Metabolic circuitsk"
1
Akella, Sridevi, et Chanchal K. Mitra. « Metabolic pathways as electronic circuits ». Dans 2011 6th International Symposium on Health Informatics and Bioinformatics (HIBIT). IEEE, 2011. http://dx.doi.org/10.1109/hibit.2011.6450815.
Texte intégral
2
Oyarzun, D. A. « Gene circuits for self-tuning metabolic pathways ». Dans IET/SynbiCITE Engineering Biology Conference. Institution of Engineering and Technology, 2016. http://dx.doi.org/10.1049/cp.2016.1220.
Texte intégral
3
Oyarzun, D. A., et G.-B. Stan. « Design tradeoffs in a synthetic gene control circuit for metabolic networks ». Dans 2012 American Control Conference - ACC 2012. IEEE, 2012. http://dx.doi.org/10.1109/acc.2012.6314705.
Texte intégral
4
Oyarzun, Diego A., et Guy-Bart Stan. « Design constraints in an operon circuit for engineered control of metabolic networks ». Dans 2012 IEEE 51st Annual Conference on Decision and Control (CDC). IEEE, 2012. http://dx.doi.org/10.1109/cdc.2012.6427048.
Texte intégral
5
Bian, Chao. « Engineering a Regulatory Circuit for Improved Nitrogen Metabolism. » Dans ASPB PLANT BIOLOGY 2020. USA : ASPB, 2020. http://dx.doi.org/10.46678/pb.20.1052935.
Texte intégral
6
Nelson, Nicole, David Sander, Marc Dandin, Anshu Sarje, Somashekar Prakash, Honghao Ji et Pamela Abshire. « A handheld fluorometer for measuring cellular metabolism ». Dans 2008 IEEE International Symposium on Circuits and Systems - ISCAS 2008. IEEE, 2008. http://dx.doi.org/10.1109/iscas.2008.4541609.
Texte intégral
7
Liang, Jingtong, et Zhe Wu. « Gene Circuit Construction and Simulation in Probiotics to Metabolize Alcohol ». Dans ICBBS 2022 : 2022 11th International Conference on Bioinformatics and Biomedical Science. New York, NY, USA : ACM, 2022. http://dx.doi.org/10.1145/3571532.3571544.
Texte intégral
8
Tsukahara, Mio, Shintaro Izumi, MotofUmi Nakanishi, Hiroshi Kawaguchi, Masahiko Yoshimoto, Hiromitsu Kimura, Kyoji Marumoto, Takaaki Fuchikami et Yoshikazu Fujimori. « A 15-μA metabolic equivalents monitoring system using adaptive acceleration sampling and normally off computing ». Dans 2016 IEEE International Conference on Electronics, Circuits and Systems (ICECS). IEEE, 2016. http://dx.doi.org/10.1109/icecs.2016.7841132.
Texte intégral
9
MacKay, Scott, Ryan Corpuz, Calvin Chong, Jie Chen et David Wishart. « Live demonstration : Portable impedance-based biosensor system for metabolomic sensing ». Dans 2016 IEEE Biomedical Circuits and Systems Conference (BioCAS). IEEE, 2016. http://dx.doi.org/10.1109/biocas.2016.7833743.
Texte intégral
10
May, Elebeoba E., et Richard L. Schiek. « Simulating metabolism in Escherichia coli K-12 — ; A circuit-based approach ». Dans 2006 IEEE Biomedical Circuits and Systems Conference - Healthcare Technology (BioCas). IEEE, 2006. http://dx.doi.org/10.1109/biocas.2006.4600314.
Texte intégralRapports d'organisations sur le sujet "Metabolic circuitsk"
1
Ron, Eliora, et Eugene Eugene Nester. Global functional genomics of plant cell transformation by agrobacterium. United States Department of Agriculture, mars 2009. http://dx.doi.org/10.32747/2009.7695860.bard.
Texte intégralRésumé :
The aim of this study was to carry out a global functional genomics analysis of plant cell transformation by Agrobacterium in order to define and characterize the physiology of Agrobacterium in the acidic environment of a wounded plant. We planed to study the proteome and transcriptome of Agrobacterium in response to a change in pH, from 7.2 to 5.5 and identify genes and circuits directly involved in this change. Bacteria-plant interactions involve a large number of global regulatory systems, which are essential for protection against new stressful conditions. The interaction of bacteria with their hosts has been previously studied by genetic-physiological methods. We wanted to make use of the new capabilities to study these interactions on a global scale, using transcription analysis (transcriptomics, microarrays) and proteomics (2D gel electrophoresis and mass spectrometry). The results provided extensive data on the functional genomics under conditions that partially mimic plant infection and – in addition - revealed some surprising and significant data. Thus, we identified the genes whose expression is modulated when Agrobacterium is grown under the acidic conditions found in the rhizosphere (pH 5.5), an essential environmental factor in Agrobacterium – plant interactions essential for induction of the virulence program by plant signal molecules. Among the 45 genes whose expression was significantly elevated, of special interest is the two-component chromosomally encoded system, ChvG/I which is involved in regulating acid inducible genes. A second exciting system under acid and ChvG/Icontrol is a secretion system for proteins, T6SS, encoded by 14 genes which appears to be important for Rhizobium leguminosarum nodule formation and nitrogen fixation and for virulence of Agrobacterium. The proteome analysis revealed that gamma aminobutyric acid (GABA), a metabolite secreted by wounded plants, induces the synthesis of an Agrobacterium lactonase which degrades the quorum sensing signal, N-acyl homoserine lactone (AHL), resulting in attenuation of virulence. In addition, through a transcriptomic analysis of Agrobacterium growing at the pH of the rhizosphere (pH=5.5), we demonstrated that salicylic acid (SA) a well-studied plant signal molecule important in plant defense, attenuates Agrobacterium virulence in two distinct ways - by down regulating the synthesis of the virulence (vir) genes required for the processing and transfer of the T-DNA and by inducing the same lactonase, which in turn degrades the AHL. Thus, GABA and SA with different molecular structures, induce the expression of these same genes. The identification of genes whose expression is modulated by conditions that mimic plant infection, as well as the identification of regulatory molecules that help control the early stages of infection, advance our understanding of this complex bacterial-plant interaction and has immediate potential applications to modify it. We expect that the data generated by our research will be used to develop novel strategies for the control of crown gall disease. Moreover, these results will also provide the basis for future biotechnological approaches that will use genetic manipulations to improve bacterial-plant interactions, leading to more efficient DNA transfer to recalcitrant plants and robust symbiosis. These advances will, in turn, contribute to plant protection by introducing genes for resistance against other bacteria, pests and environmental stress.