932 resultados para energy and protein restriction


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Although a variety of nanoparticles (NPs) functionalized with amphotericin B, an antifungal agent widely used in the clinic, have been studied in the last years their cytotoxicity profile remains elusive. Here we show that human endothelial cells take up high amounts of silica nanoparticles (SNPs) conjugated with amphotericin B (AmB) (SNP-AmB) (65.4 12.4 pg of Si per cell) through macropinocytosis while human fibroblasts internalize relatively low amounts (2.3 0.4 pg of Si per cell) because of their low capacity for macropinocytosis. We further show that concentrations of SNP-AmB and SNP up to 400 mg/mL do not substantially affect fibroblasts. In contrast, endothelial cells are sensitive to low concentrations of NPs (above 10 mg/mL), in particular to SNP-AmB. This is because of their capacity to internalize high concentration of NPs and high sensitivity of their membrane to the effects of AmB. Low-moderate concentrations of SNP-AmB (up to 100 mg/mL) induce the production of reactive oxygen species (ROS), LDH release, high expression of pro-inflammatory cytokines and chemokines (IL-8, IL-6, G-CSF, CCL4, IL-1b and CSF2) and high expression of heat shock proteins (HSPs) at gene and protein levels. High concentrations of SNP-AmB (above 100 ug/mL) disturb membrane integrity and kill rapidly human cells(60% after 5 h). This effect is higher in SNP-AmB than in SNP.

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Nowadays it is known that the human body is continuous source of many types of energy and the devices used for collecting energy taken from the environment also have the required capabilities for the collection of the energy produced by the Human body (HB), but very limited and with very low efficiency. Low power and high yield converters are particularly needed in these cases of collecting energy from human activity and its movements due to the small amount of energy generated this way. But this situation can be improved. Enhancing or focusing the human movements by using mechanical amplifiers applied to the piezoelectric element. By doing so the input of energy in the element increases. As such increasing its output, therefore producing more energy.

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The reduction of greenhouse gas emissions is one of the big global challenges for the next decades due to its severe impact on the atmosphere that leads to a change in the climate and other environmental factors. One of the main sources of greenhouse gas is energy consumption, therefore a number of initiatives and calls for awareness and sustainability in energy use are issued among different types of institutional and organizations. The European Council adopted in 2007 energy and climate change objectives for 20% improvement until 2020. All European countries are required to use energy with more efficiency. Several steps could be conducted for energy reduction: understanding the buildings behavior through time, revealing the factors that influence the consumption, applying the right measurement for reduction and sustainability, visualizing the hidden connection between our daily habits impacts on the natural world and promoting to more sustainable life. Researchers have suggested that feedback visualization can effectively encourage conservation with energy reduction rate of 18%. Furthermore, researchers have contributed to the identification process of a set of factors which are very likely to influence consumption. Such as occupancy level, occupants behavior, environmental conditions, building thermal envelope, climate zones, etc. Nowadays, the amount of energy consumption at the university campuses are huge and it needs great effort to meet the reduction requested by European Council as well as the cost reduction. Thus, the present study was performed on the university buildings as a use case to: a. Investigate the most dynamic influence factors on energy consumption in campus; b. Implement prediction model for electricity consumption using different techniques, such as the traditional regression way and the alternative machine learning techniques; and c. Assist energy management by providing a real time energy feedback and visualization in campus for more awareness and better decision making. This methodology is implemented to the use case of University Jaume I (UJI), located in Castellon, Spain.

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This work project takes the format of a problem-solving approach suggested by “Impulse Partners”, a French consulting firm. It recommends a way to measure the success of ten startups in the incubators “Starburst” and “Incubator Construction & Energyand give them strategic guidance. A Balanced Scorecard is elaborated to help incubated startups building up and implementing their strategy. The Scorecard suggests possible initiatives for the startups that are ideally realized with the help of the consulting firm that is steering the incubator. Special attention is drawn to what the startups need to succeed, which typically concerns financing, networking and managing skills.

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Prolonged total food deprivation in non-obese adults is rare, and few studies have documented body composition changes in this setting. In a group of eight hunger strikers who refused alimentation for 43 days, water and energy compartments were estimated, aiming to assess the impact of progressive starvation. Measurements included body mass index (BMI), triceps skinfold (TSF), arm muscle circumference (AMC), and bioimpedance (BIA) determinations of water, fat, lean body mass (LBM), and total resistance. Indirect calorimetry was also performed in one occasion. The age of the group was 43.3±6.2 years (seven males, one female). Only water, intermittent vitamins and electrolytes were ingested, and average weight loss reached 17.9%. On the last two days of the fast (43rd-44th day) rapid intravenous fluid, electrolyte, and vitamin replenishment were provided before proceeding with realimentation. Body fat decreased approximately 60% (BIA and TSF), whereas BMI reduced only 18%. Initial fat was estimated by BIA as 52.2±5.4% of body weight, and even on the 43rd day it was still measured as 19.7±3.8% of weight. TSF findings were much lower and commensurate with other anthropometric results. Water was comparatively low with high total resistance, and these findings rapidly reversed upon the intravenous rapid hydration. At the end of the starvation period, BMI (21.5±2.6 kg/m²) and most anthropometric determinations were still acceptable, suggesting efficient energy and muscle conservation. Conclusions: 1) All compartments diminished during fasting, but body fat was by far the most affected; 2) Total water was low and total body resistance comparatively elevated, but these findings rapidly reversed upon rehydration; 3) Exaggerated fat percentage estimates from BIA tests and simultaneous increase in lean body mass estimates suggested that this method was inappropriate for assessing energy compartments in the studied population; 4) Patients were not morphologically malnourished after 43 days of fasting; however, the prognostic impact of other impairments was not considered in this analysis.

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RESUMO: Na sociedade contemporânea a diabetes tipo 2 e a obesidade estão a aumentar exponencialmente, representando um grave problema de saúde pública. De acordo com a IDF “A diabetes e a obesidade são o principal problema de saúde pública do século XXI’. Para além destas duas patologias, a prevalência de esteatose hepática não-alcoólica (NAFLD), entre a população obesa e diabética, é de cerca de 90%. O aumento da obesidade, diabetes e NAFLD tem uma forte correlação com o aumento do consumo de gorduras e açúcares, acompanhado de um decréscimo acentuado da actividade física. A obesidade, diabetes e NAFLD tem sido escrupolosamente investigada mas as terapêuticas disponíveis continuam a ser muito limitadas. Tendo em conta o número crescente e alarmante de obesos e diabéticos o conhecimento detalhado da patofisiologia da obesidade, diabetes e NAFLD, tendo em vista a necessidade extrema de desenvolvimento de novas estratégias terapêuticas, é da mais elevada urgência. O fígado é reconhecido como um orgão primordial no controlo da homeostase. No estado pós-prandial, o fígado converte a glucose em glicogénio e lípidos. Em contraste, no estado de jejum, o fígado promove a produção de glucose. Sistemas neuronais e hormonais, bem como o estado metabólico do fígado, controlam de forma muito precisa a alternância entre os diferentes substratos metabólicos, dependente do estado prandial. A insulina tem um papel central no controlo do metabolismo energético no fígado; se, por um lado, inibe a produção hepática de glucose e corpos cetónicos, por outro, promove a glicólise e a lipogénese. O metabolismo energético no fígado é também regulado por vários factores de transcrição e co-reguladores que, por sua vez, são regulados pela insulina, glucagina e outras hormonas metabólicas. Em conjunto, todos estes factores e reguladores vão controlar de forma muito estreita a gluconeogénese, a β-oxidação e a lipogénese, no fígado. Para além dos já conhecidos reguladores do metabolismo hepático, novas moléculas têm sido estudadas como tendo um papel fundamental na regulação do metabolismo energético no fígado. Qualquer desequilíbrio no metabolismo hepático vai contribuir para a insulino-resistência, NAFLD e diabetes tipo 2. O principal objectivo do trabalho de investigação aqui apresentado é o contributo para o estudo detalhado da patogénese da diabetes e obesidade, num contexto de dietas ricas em açúcares e gorduras, e com a perspectiva de explorar novas estratégias terapêuticas. Os objectivos específicos deste trabalho eram: primeiro, determinar se o tratamento com glutationo (GSH) e óxido nítrico (NO) era suficiente para melhorar a insulino-resistência associada ao elevado consumo de sacarose; segundo, determinar o papel da Rho-kinase 1 (ROCK1) na regulação do metabolismo hepático da glucose e dos lípidos; e terceiro, estudar o efeito do metilsulfonilmetano (MSM) em doenças metabólicas associadas à obesidade. Na primeira parte deste trabalho de investigação foram utilizados ratos Wistar machos sujeitos a uma dieta rica em sacarose (HS). Tal como esperado, estes animais apresentavam insulino-resistência e hiperinsulinémia. A dieta HS levou ao aumento dos níveis hepáticos de NO e ao decréscimo dos níveis de GSH no fígado. Em jejum, a administração intraportal de GSH e NO, a animais saudáveis promoveu um aumento significativo da sensibilidade à insulina. Também nestes animais, a administração intravenosa de S-nitrosotióis, compostos orgânicos que contém um grupo nitroso acoplado a um átomo de enxofre de um tiol, promoveu o aumento significativo da sensibilidade à insulina. Pelo contrário, em animais sujeitos à dieta HS, as doses padrão de GSH + NO e de S-nitrosotióis não conseguiram promover o aumento da sensibilidade à insulina. No entanto, ao aumentar a dose de S-nitrosotióis administrados por via intravenosa, foi possível observar o aumento da sensibilidade à insulina dependente da dose, indicando um possível papel dos S-nitrosotióis como sensibilizadores de insulina. O estudo detalhado do papel dos S-nitrosotióis na via de sinalização da insulina revelou que há um aumento da fosforilação do receptor da insulina (IR) e da proteína cinase B (Akt), sugerindo um efeito dos S-nitrosotióis nesta via de sinalização. Os resultados apresentados nesta primeira parte sugerem que os S-nitrosotióis promovem a correcta acção da insulina, podendo vir a ser importantes alvos terapêuticos. Na segunda parte deste trabalho de investigação utilizámos murganhos, com uma delecção específica da ROCK1 no fígado, e sujeitos a uma dieta rica em lípidos (HFD). Foi possível concluir que a ausência da ROCK1 no fígado previne a obesidade, melhora a sensibilidade à insulina e protege contra a esteatose hepática. A ausência de ROCK1 no fígado levou a um decréscimo significativo da expressão génica de genes associados à lipogénese, com uma diminuição acentuada do fluxo metabólico associado a esta via. Pelo contrário, a sobreexpressão de ROCK1, exclusivamente no fígado, promove a insulino-resistência e a esteatose hepática no contexto de obesidade induzida pela dieta. Para além disto, a delecção da ROCK1 no fígado de animais obesos e diabéticos, os murganhos deficientes em leptina, corroborou os dados obtidos no primeiro modelo animal, com a franca melhoria da hiperglicémia, hiperinsulinémia e esteatose hepática. Os dados que compõem esta parte do trabalho de investigação sugerem que a ROCK1 tem um papel crucial na regulação do metabolismo lipídico. Na terceira e última parte deste trabalho de investigação foi investigado o efeito do composto metilsulfunilmetano (MSM), um composto organosulfúrico naturalmente presente em plantas e utilizado também como suplemento dietético, em murganhos obesos e insulino-resistentes, por exposição a uma dieta rica em lípidos (DIO). O tratamento com MSM melhorou a insulino-resistência e protegeu contra a esteatose hepática. O conteúdo hepático em triglicéridos e colesterol também diminuíu de forma significativa nos animais DIO sujeitos ao tratamento com MSM, bem como a expressão génica associada à lipogénese. Para além disto, o tratamento com MSM levou a uma diminuição da expressão génica associada à inflamação. De realçar que o tratamento com MSM levou a uma melhoria do perfil hematopoiético destes animais, tanto na medula óssea como no sangue. Para comprovar o efeito benéfico do MSM na obesidade e insulino-resistência utilizámos murganhos deficientes no receptor da leptina, e por isso obesos e diabéticos, tendo observado um perfil semelhante ao obtido para murganhos sujeitos a uma dieta rica em lípidos e tratados com MSM. Concluímos, através dos dados recolhidos, que o MSM como suplemento pode ter efeitos benéficos na hiperinsulinémia, insulino-resistência e inflamação que caracterizam a diabetes tipo 2. Em resumo, os dados obtidos neste trabalho de investigação mostram que os S-nitrosotióis podem ter um papel importante como sensibilizadores da insulina, promovendo um aumento da sensibilidade à insulina num contexto de dietas ricas em sacarose. Para além disto, estudos in vitro, sugerem que os S-nitrosotióis regulam, especificamente, a via de sinalização da insulina. Este trabalho teve também como objectivo o estudo da ROCK1 como regulador do metabolismo da glucose e dos lípidos no fígado. Através do estudo de animais com uma delecção ou uma sobreexpressão da ROCK1 no fígado mostrou-se que esta tem um papel crucial na patogénese da obesidade e diabetes tipo 2, especificamente através do controlo da lipogénese de novo. Finalmente, foi também objectivo deste trabalho, explorar o efeito do MSM em animais DIO e deficientes em leptina. O tratamento com MSM protege de forma evidente contra a obesidade e insulino-resistência, com especial enfâse para a capacidade que esta molécula demonstrou ter na protecção contra a inflamação. Em conjunto os vários estudos aqui apresentados mostram que tanto os S-nitrosotióis como a ROCK1 têm um papel na patogénese da obesidade e diabetes tipo 2 e que a utilização de MSM como suplemento às terapêuticas convencionais pode ter um papel no tratamentos de doenças metabólicas.-------------------------------ABSTRACT: In modern western societies type 2 diabetes and obesity are increasing exponentially, representing a somber public concern. According to the International Diabetes Federation (IDF) ‘Diabetes and Obesity are the biggest public health challenges of the 21st century’. Aside from these the prevalence of nonalcoholic fatty liver disease (NAFLD), among the diabetic and obese population, is as high as 90%. It is now well established that the increase in obesity, diabetes and NAFLD strongly correlates with an increase in fat and sugar intake in our diet, alongside physical inactivity. The pathogenesis of obesity, diabetes and NAFLD has been thoroughly studied but the treatment options available are still narrow. Considering the alarming number in the obese and diabetic population the complete understanding of the pathogenesis, keeping in mind that new therapeutic strategies need to be attained, is of the highest urgency. The liver has been well established as a fundamental organ in regulating whole-body homeostasis. In the fed state the liver converts the glucose into glycogen and lipids. Conversely, in the fasted state, glucose will be produced in the liver. Neuronal and hormonal systems, as well as the hepatic metabolic states, tightly control the fast to fed switch in metabolic fuels. Insulin has a central role in controlling hepatic energy metabolism, by suppressing glucose production and ketogenesis, while stimulating glycolysis and lipogenesis. Liver energy metabolism is also regulated by various transcription factors and coregulators that are, in turn, regulated by insulin, glucagon and other metabolic hormones. Together, these regulators will act to control gluconeogenesis, β-oxidation and lipogenesis in the liver. Aside from the well-established regulators of liver energy metabolism new molecules are being studied has having a role in regulating hepatic metabolism. Any imbalance in the liver energy metabolism is a major contributor to insulin resistance, NAFLD and type 2 diabetes. The overall goal of this research work was to contribute to the understanding of the pathogenesis of diabetes and obesity, on a setting of high-sucrose and high-fat diets, and to explore potential therapeutic options. The specific aims were: first, to determine if treatment with glutathione (GSH) and nitric oxide (NO) was sufficient to ameliorate insulin resistance induced by high-sucrose feeding; second, to determine the physiological role of rho-kinase 1 (ROCK1) in regulating hepatic and lipid metabolism; and third, to study the effect of methylsulfonylmethane (MSM) on obesity-linked metabolic disorders. In the first part of this research work we used male Wistar rats fed a high-sucrose (HS) diet. As expected, rats fed a HS diet were insulin resistant and hyperinsulinemic. HS feeding increased hepatic levels of NO, while decreasing GSH. In fasted healthy animals administration of both GSH and NO, to the liver, was able to increase insulin sensitivity. Intravenous administration of S-nitrosothiols, organic compounds containing a nitroso group attached to the sulfur atom of a thiol, in fasted control animals also increased insulin sensitivity. Under HS feeding the standard doses of GSH + NO and S-nitrosothiols were unable to promote an increase in insulin sensitivity. However, the intravenous administration of increasing concentrations of S-nitrosothiols was able to restore insulin sensitivity, suggesting that S-nitrosothiols have an insulin sensitizing effect. Investigation of the effect of S-nitrosothiols on the insulin signaling pathway showed increased phosphorylation of the insulin receptor (IR) and protein kinase B (Akt), suggesting that S-nitrosothiols may have an effect on the insulin signaling pathway. Together, these data showed that S-nitrosothiols promote normal insulin action, suggesting that they may act as potential pharmacological tools. In the second part of this research work we used liver-specific ROCK1 knockout mice fed a high-fat (HF) diet. Liver-specific deletion of ROCK1 prevented obesity, improved insulin sensitivity and protected against hepatic steatosis. Deficiency of ROCK1 in the liver caused a significant decrease in the gene expression of lipogenesis associated gene, ultimately leading to decreased lipogenesis. Contrariwise, ROCK1 overexpression in the liver promoted insulin resistance and hepatic steatosis in diet-induced obesity. Furthermore, liver-specific deletion of ROCK1 in obese and diabetic mice, the leptin-deficient mice, improved the typical hyperglycemia, hyperinsulinemia and liver steatosis. Together, these data identify ROCK1 as a crucial regulator of lipid metabolism. In the third and final part of this research work we investigated the effect of MSM, an organosulfur compound naturally found in plants and used as a dietary supplement, on diet-induced obese (DIO) and insulin resistant mice. MSM treatment ameliorated insulin resistance and protected against hepatosteatosis. Hepatic content in triglycerides and cholesterol was significantly decreased by MSM treatment, as well as lipogenesis associated gene expression. Furthermore, MSM treated mice had decreased inflammation associated gene expression in the liver. Importantly, FACS analysis showed that MSM treatment rescued the inflammatory hematopoietic phenotype of DIO mice in the bone marrow and the peripheral blood. Moreover, MSM treatment of the obese and diabetic mice, the leptin-deficient mice, resulted in similar effects as the ones observed for DIO mice. Collectively, these data suggest that MSM supplementation has a beneficial effect on hyperinsulinemia, insulin resistance and inflammation, which are often found in type 2 diabetes. In conclusion, this research work showed that S-nitrosothiols may play a role as insulin sensitizers, restoring insulin sensitivity in a setting of high-sucrose induced insulin resistance. Furthermore, in vitro studies suggest that S-nitrosothiols specifically regulate the insulin signaling pathway. This research work also investigated the role of hepatic ROCK1 in regulation of glucose and lipid metabolism. Using liver-specific ROCK 1 knockout and ROCK1 overexpressing mice it was shown that ROCK1 plays a role in the pathogenesis of obesity and type 2 diabetes, specifically through regulation of the de novo lipogenesis pathway. Finally, this research work aimed to explore the effect of MSM in DIO and leptin receptor-deficient mice. MSM strongly protects against obesity and insulin resistance, moreover showed a robust ability to decrease inflammation. Together, the individual studies that compose this dissertation showed that S-nitrosothiols and ROCK1 play a role in the pathogenesis of obesity and type 2 diabetes and that MSM supplementation may have a role in the treatment of metabolic disorders.

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The building sector is one of the Europeâ s main energy consumer, making buildings an important target for a wiser energy use, improving indoor comfort conditions and reducing the energy consumption. To achieve the European Union targets for energy consumption and carbon reductions it is crucial to act in new, but also in existing buildings, which constitute the majority of the building stock. In existing buildings, the significant improvement of their efficiency requires important investments. Therefore, costs are a major concern in the decision making process and the analysis of the cost effectiveness of the interventions is an important path in the guidance for the selection of the different renovation scenarios. The Portuguese thermal legislation considers the simple payback method for the calculations of the time for the return of the investment. However, this method does not take into consideration inflation, cash flows and cost of capital, as well as the future costs of energy and the building elements lifetime as it happens in a life cycle cost analysis. In order to understand the impact of the economic analysis method used in the choice of the renovation measures, a case study has been analysed using simple payback calculations and life cycle costs analysis. Overall results show that less far-reaching renovation measures are indicated when using the simple payback calculations which may be leading to solutions less cost-effective in a long run perspective.

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This paper describes the trigger and offline reconstruction, identification and energy calibration algorithms for hadronic decays of tau leptons employed for the data collected from pp collisions in 2012 with the ATLAS detector at the LHC center-of-mass energy s√ = 8 TeV. The performance of these algorithms is measured in most cases with Z decays to tau leptons using the full 2012 dataset, corresponding to an integrated luminosity of 20.3 fb−1. An uncertainty on the offline reconstructed tau energy scale of 2% to 4%, depending on transverse energy and pseudorapidity, is achieved using two independent methods. The offline tau identification efficiency is measured with a precision of 2.5% for hadronically decaying tau leptons with one associated track, and of 4% for the case of three associated tracks, inclusive in pseudorapidity and for a visible transverse energy greater than 20 GeV. For hadronic tau lepton decays selected by offline algorithms, the tau trigger identification efficiency is measured with a precision of 2% to 8%, depending on the transverse energy. The performance of the tau algorithms, both offline and at the trigger level, is found to be stable with respect to the number of concurrent proton--proton interactions and has supported a variety of physics results using hadronically decaying tau leptons at ATLAS.

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Tese de Doutoramento em Biologia Molecular e Ambiental (área de especialização em Biologia Celular e Saúde).

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Energy from waste (E/W) technologies in the form o f biogas plants, CHP plants and other municipal solid waste (MSW) conversion technologies, have been gaining steady ground in the provision o f energy throughout Europe and the UK. Urban Waste Water Treatment Plants (UWWTP) are utilising much o f the same biochemical processes common to these E/W plants. Previous studies on Centralised Anaerobic Digestion (CAD) within Ireland found that the legislative and economic conditions were not conducive to such an operation on the grounds o f low energy price for electric and heat energy, and due to the restrictive nature o f the allowable feedstocks. Recent changes to the Irish REFIT tariff on energy produced from Anaerobic digestion; alterations to the regulation o f the allowable use o f animal by products(ABP); the recent enactment o f the Renewable Energy D irective (09/28/EC) and a subsequent review o f the draft Biowaste Directive (2001) required that the issue o f decentralised energy production in Ireland be reassessed. In this instance the feasibility study is based on a extant rural community, centred around the village o f Woodford Co Galway. The review found that the prevailing conditions were now such that it was technically and economically feasible for this biochemical process to provide energy and waste treatment facilities at the above location. The review also outlines the last item which is preventing this process from becoming achievable, specifically the lack o f a digestate regulation on land spreading which deals specifically with biowaste. The study finds that the implementation o f the draft EU biowaste regulations, with amendments for Cr and Hg levels to match the proposed Irish regulation for compost, would ensure that Ireland has some o f the most restrictive regulations in Europe for this application. The delay in completing this piece o f legislation is preventing national energy and waste issues from being resolved in a planned and stepwise fashion. A proposed lay out for the new Integrated Waste from Energy Plant (IW/EP) is presented. Budget economic projections and alternative revenue streams are outlined. Finally a review o f the national policies regarding the Rural Development Plan (RDP), the Rural Planning Guidelines (RPG) and the National Renewable Energy Action Plan (NREAP) are examined against the relevant EU directives.

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HYPOTHESIS: Liver transplantation results in hepatic denervation. This may produce alterations of liver energy and substrate metabolism, which may contribute to weight gain after liver transplantation. DESIGN: Prospective clinical study. SETTING: Liver transplantation clinics in a university hospital. PATIENTS: Seven nondiabetic patients with cirrhosis were recruited while on a waiting list for liver transplantation. Seven healthy subjects were recruited as controls. INTERVENTION: Orthotopic liver transplantation. MAIN OUTCOME MEASURES: Evaluation of energy and substrate metabolism after ingestion of a glucose load with indirect calorimetry was performed before, 2 to 6 weeks after, and 5 to 19 months after transplantation. Whole-body glucose oxidation and storage and glucose-induced thermogenesis were calculated. RESULTS: Patients with cirrhosis had modestly elevated resting energy expenditure and normal glucose-induced thermogenesis and postprandial glucose oxidation and storage. These measures remained unchanged after liver transplantation despite a significant increase in postprandial glycemia. Patients, however, gained an average of 3 kg of body weight after 5 to 19 months compared with their weight before transplantation. CONCLUSION: Liver denervation secondary to transplantation does not lead to alterations of energy metabolism after ingestion of a glucose load.

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In northeast Brazil, nutritional deficiency diseases and schistosomiasis mansoni overlap. An experimental model, wich reproduces the marasmatic clinical form of protein-energy malnutrition, was developed in this laboratory to study these interactions. Albino Swiss mice were fed with a food association ingested usually by human populations in northeast Brazil. This diet (Regional Basic Diet - RBD) has negative effects on the growth, food intake and protein utilization in infected mice (acute phase of murine schistosomiasis). Nitrogen balance studies have also shown that infection with Schistosoma mansoni has apparently no effect on protein intestinal absorption in well nourished mice. However, the lowest absorption ratios have been detected among RBD - fed infected animals, suggesting that suprerimposed schistosome infection aggravated the nutritional status of the undernourished host. The serum proteins electrophoretic pattern, as far as albumins are concerned, is quite similar for non-infected undernourished and infected well-fed animals. So, the significance of albumins as a biochemical indicator of the nutritional status of human populations residing in endemic foci of Manson's schistosomiasis, is discussable.

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SUMMARY: EBBP is a poorly characterized member of the RBCC/TRIM family (RING finger B-box coiled-coilltripartite motif). It is ubiquitously expressed, but particularly high levels are found in keratinocytes. There is evidence that EBBP is involved in inflammatory processes, since it can interact with pro-interleukin-1 ß (prolL-1 ß) in human macrophages and keratinocytes, and its downregulation results in reduced secretion of IL-1 ß. IL-1ß activation and secretion requires the proteolytic cleavage of prolL-1ß by caspase-1, which in turn is actìvated by a protein complex called the inflammasome. As it has been demonstrated that EBBP can bind two different proteins of the inflammasome (NALP-1 and caspase 1), we assumed that EBBP plays a role in the regulation of inflammation and that the inflammasome, which has as yet only been described in ínflammatory cells, may also exist in keratinocytes. Indeed, I could show in my thesis that the inflammasome components are expressed in human keratinócytes at the RNA and protein level and also in vivo in human epidermis. After irradiation with a physiological dose of UVB, keratinocytes activated prolL-1ß and secreted prolL-1 a, IL-1 ß, prolL-18 and inflammasome proteins, although all these proteins lack a classical signal peptide. The secretion was dependent on caspase-1 activity, but not on de novo protein synthesis. Knock-down of NALP1 and -3, caspase-1 and -5, EBBP and Asc strongly reduced the secretion of IL-1 ß, demonstrating that also in keratinocytes inflammasome proteins are directly involved in maturation of this cytokine. These results demonstrate for the first time the presence of an active inflammasome in non-professional immune cells. Moreover, they show that UV irradiation is a stimulus for inflammasome activation in keratinocytes. For the analysis of the ín vivo functions of EBBP, transgenic mice overexpressing EBBP in the epidermis were generated. To examine the influence of EBBP overexpression on inflammatory processes, we subjected the mice to different challenges, which induce inflammation. Wound-healing, UVB irradiation and delayed hypersensitivity were tested, but we did not observe any phenotype in the K14-EBBP mice. Besides, a conditional ebbp knockout mouse has been obtained, which will allow to determine the effects of EBBP gene deletion in different tissues and organs. RESUME: EBBP est un membre encore mal connu de la famille des RBCC/TRIM (RING finger B-box coiled-coil/tripartite motif). Il est exprimé de manière ubiquitaire, et en particulier dans les kératinocytes. EBBP étant capable d'interagir avec la prointerleukine-1 ß (prolL-1 ß) dans les macrophages et les kératinocytes humains et de réguler la sécrétion de l'IL-1 ß, il est très probable que cette protéine est impliquée dans l'inflammation. L'activation et la sécrétion de l'IL-1 ß requièrent le clivage protéolytique de son précurseur prolL-1ß par la caspase-1, qui est elle-même activée par un complexe protéique appelé l'inflammasome. Comme il a été démontré qu'EBBP peut lier deux protéines de l'inflammasome (NALP-1 et caspase-1), nous avons émis l'hypothèse qu'EBBP joue un rôle dans la régulation de l'inflammation et que l'inflammasome, jusqu'ici décrit exclusivement dans des cellules inflammatoires, existe dans les kératinocytes. En effet, j'ai pu montrer dans ma thèse que les composants de l'inflammasome sont exprimés dans les kératinocytes humains ainsi que in vivo dans l'épiderme humain. Après irradiation avec une dose, physiologique d'UVB, les kératinocytes activent la prolL-1 ß et sécrètent la prolL-1a, l'IL-1 ß, la prolL-18 et des protéines de l'inflammasome, bien que toutes ces protéines soient dépourvues de peptide signal. La sécrétion dépend de la caspase-1 mais pas de la synthèse protéique de novo. Le knock-down de NALP-1 et -3, des caspase-1 et -5, d'EBBP et d'Asc réduit de manière marquée la sécrétion d'IL-1 ß, démontrant que dans les kératinocytes également, les protéines de l'inflammasome sont impliquées directement dans la maturation de cette cytokine. Ces résultats démontrent pour la première fois la présence d'un inflammasome actif dans des cellules immunitaires non professionnelles. De plus, ils montrent que l'irradiation aux UV est un stimulus pour l'activation de l'inflammasome dans les kératinocytes. Pour l'analyse des fonctions d'EBBP in vivo, nous avons généré des souris transgéniques qui surexpriment EBBP dans l'épiderme. En vue d'examiner l'influence de la surexpression d'EBBP sur le processus inflammatoire, nous avons soumis ces souris à differents modèles d'inflammation. Nous avons testé cicatrisation, UVB et hypersensibilité retardée, mais n'avons pas observé de phénotype chez les souris transgéniques. En parallèle, nous avons également généré des souris knock-out pour ebbp qui devraient nous permettre de déterminer les effets de la suppression d'EBBP dans différents tissus et organes.

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OBJECTIVES: Increasing evidence suggests that left ventricular remodeling is associated with a shift from fatty acid to glucose metabolism for energy production. The aim of this study was to determine whether left ventricular remodeling with and without late-onset heart failure after myocardial infarction is associated with regional changes in the expression of regulatory proteins of glucose or fatty acid metabolism. METHODS: Myocardial infarction was induced in rats by ligation of the left anterior descending coronary artery (LAD). In infarcted and sham-operated hearts the peri-infarction region (5-mm zone surrounding the region at risk), the interventricular septum and the right ventricular free wall were separated for analysis. RESULTS: At 8 and 20 weeks after LAD ligation, the peri-infarction region and the septum exhibited marked re-expression of atrial natriuretic factor [+252+/-37 and +1093+/-279%, respectively, in the septum (P<0.05)] and of alpha-smooth muscle actin [+34+/-10 and +43+/-14%, respectively, in the septum (P<0.05)]. At 8 weeks, when left ventricular hypertrophy was present without signs of heart failure, myocardial mRNA expression of glucose transporters (GLUT-1 and GLUT-4) was not altered, whereas mRNA expression of medium-chain acyl-CoA dehydrogenase (MCAD) was significantly reduced in the peri-infarction region (-25+/-7%; P<0.05). In hearts exhibiting heart failure 20 weeks after infarct-induction there was a change in all three ventricular regions of both mRNA and protein content of GLUT-1 [+72+/-28 and +121+/-15%, respectively, in the peri-infarction region (P<0.05)] and MCAD [-29+/-9 and -56+/-4%, respectively, in the peri-infarction region (P<0.05)]. CONCLUSION: In rats with large myocardial infarction, progression from compensated remodeling to overt heart failure is associated with upregulation of GLUT-1 and downregulation of MCAD in both the peri-infarction region and the septum.