Anti-Inflammatory Effect of Fluvastatin on IL-8 Production Induced by Pseudomonas aeruginosa and Aspergillus fumigatus Antigens in Cystic Fibrosis

International audienceBACKGROUND: Early in life, patients with cystic fibrosis (CF) are infected with microorganisms including bacteria and fungi, particularly Pseudomonas aeruginosa and Aspergillus fumigatus. Since recent research has identified the anti-inflammatory properties of statins (besides their lipid-lowering effects), we investigated the effect of fluvastatin on the production of the potent neutrophil chemoattractant chemokine, IL-8, in whole blood from CF patients, stimulated by Pseudomonas aeruginosa (LPS) and Aspergillus fumigatus (AFA) antigens. RESULTS: Whole blood from adult patients with CF and from healthy volunteers was collected at the Rennes University Hospital (France). Blood was pretreated for 1 h with fluvastatin (0-300 µM) and incubated for 24 h with LPS (10 µg/mL) and/or AFA (diluted 1/200). IL-8 protein levels, quantified by ELISA, were increased in a concentration-dependent manner when cells were stimulated by LPS or AFA. Fluvastatin strongly decreased the levels of IL-8, in a concentration-dependent manner, in whole blood from CF patients. However, its inhibitory effect was decreased or absent in whole blood from healthy subjects. Furthermore, the inhibition induced by fluvastatin in CF whole blood was reversed in the presence of intermediates within the cholesterol biosynthesis pathway, mevalonate, farnesyl pyprophosphate or geranylgeranyl pyrophosphate that activate small GTPases by isoprenylation. CONCLUSIONS: For the first time, the inhibitory effects of fluvastatin on CF systemic inflammation may reveal the important therapeutic potential of statins in pathological conditions associated with the over-production of pro-inflammatory cytokines and chemokines as observed during the manifestation of CF. The anti-inflammatory effect could be related to the modulation of the prenylation of signalling proteins

Contribution à l’étude des aspects mécaniques et thermiques des générateurs de forte puissance pour les EMR

The development of high power generators for the marine renewable energies requires substantial research and development, focusing particularly on the mechanical and thermal aspects. Generally, accurate modelling of electrical machines requires the use of finite-element (fe) method. However, fe analysis is highly time consuming, especially at first design stages. The aim of this phd thesis is to propose a design approach of the permanent magnet synchronous generators for marine renewable energies applications offering a good computation time to precision ratio. Two design models are proposed in this work : lumped parameter approach and a hybrid approach based on the direct coupling of an analytical model and lumped parameter model. This modelling approach is used for the modelling of the three main physics to be considered in an electrical generator (magnetic model, thermal model and mechanical model). The lumped parameters approach consists, in this thesis, in the development of a generic magnetica and thermic lumped parameter network linked to the machine geometry. The models developed will regroup the ongoing developments of thermal and mechanical models at the GREAH lab in order to reach the completion of a mutliphysics lumped parameters computational code.Le développement des générateurs de forte puissance pour les énergies marines renouvelables nécessite un effort important de recherche et de développement plus particulièrement centre sur les aspects mécaniques et thermiques. Généralement, la modélisation précise des machines électriques nécessite l'utilisation de la méthode des éléments finis. Cependant, cette méthode est gourmande en temps de calcul en particulier lors des premières étapes de conception. Le but de cette thèse est de fournir des modèles permettant l’analyse des générateurs synchrones à aimants permanents pour les énergies marines renouvelables avec un rapport temps / précision réduit. Deux approches de modélisation sont proposées dans ce travail: une approche à constantes localisées et une approche hybride basée sur le couplage direct entre un modèle analytique et un modèle à constantes localisées. Ces modèles sont utilisés pour l'étude des différents phénomènes physiques inhérents au fonctionnement des dispositifs électromagnétiques (magnétiques, thermiques et mécaniques). Les modèles magnétiques et thermiques à constantes localisées sont construits à partir d'une démarche dite générique, consistant en un maillage du domaine d'étude. Les modèles développés enrichiront les travaux en cours sur les modèles thermiques et mécaniques au GREAH afin d'aboutir à un code de calcul multi-physique par constantes localisées

Contribution to the study of the mechanical and thermal aspects of hight power generators for the marine renewable energies

Le développement des générateurs de forte puissance pour les énergies marines renouvelables nécessite un effort important de recherche et de développement plus particulièrement centre sur les aspects mécaniques et thermiques. Généralement, la modélisation précise des machines électriques nécessite l'utilisation de la méthode des éléments finis. Cependant, cette méthode est gourmande en temps de calcul en particulier lors des premières étapes de conception. Le but de cette thèse est de fournir des modèles permettant l’analyse des générateurs synchrones à aimants permanents pour les énergies marines renouvelables avec un rapport temps / précision réduit. Deux approches de modélisation sont proposées dans ce travail: une approche à constantes localisées et une approche hybride basée sur le couplage direct entre un modèle analytique et un modèle à constantes localisées. Ces modèles sont utilisés pour l'étude des différents phénomènes physiques inhérents au fonctionnement des dispositifs électromagnétiques (magnétiques, thermiques et mécaniques). Les modèles magnétiques et thermiques à constantes localisées sont construits à partir d'une démarche dite générique, consistant en un maillage du domaine d'étude. Les modèles développés enrichiront les travaux en cours sur les modèles thermiques et mécaniques au GREAH afin d'aboutir à un code de calcul multi-physique par constantes localisées.The development of high power generators for the marine renewable energies requires substantial research and development, focusing particularly on the mechanical and thermal aspects. Generally, accurate modelling of electrical machines requires the use of finite-element (fe) method. However, fe analysis is highly time consuming, especially at first design stages. The aim of this phd thesis is to propose a design approach of the permanent magnet synchronous generators for marine renewable energies applications offering a good computation time to precision ratio. Two design models are proposed in this work : lumped parameter approach and a hybrid approach based on the direct coupling of an analytical model and lumped parameter model. This modelling approach is used for the modelling of the three main physics to be considered in an electrical generator (magnetic model, thermal model and mechanical model). The lumped parameters approach consists, in this thesis, in the development of a generic magnetica and thermic lumped parameter network linked to the machine geometry. The models developed will regroup the ongoing developments of thermal and mechanical models at the GREAH lab in order to reach the completion of a mutliphysics lumped parameters computational code

Comparative effects of some carbohydrates on serum sugars, triglycerides and digestive hydrolases

International audienc

Capacity building strategies and policy for desalination using renewable energies in Algeria

The integration of renewable resources in desalination and water purification is becoming increasingly attractive. This is justified by the fact that areas of fresh water shortages have plenty of solar energy and these technologies have low operating and maintenance costs. In this paper, an overview of capacity building strategy and policy for desalination in Algeria is presented. Importance of training and education on renewable energies is also outlined. The contribution of the Middle East Desalination Research Center in capacity building and research and development in desalination in Algeria is also presented.Capacity building Renewable energy Desalination Education Research

Thermal modelling of tubular linear machines using a hybrid analytical method

The aim of this paper is to apply a hybrid analytical method (HAM) for the thermal modelling of tubular linear machines. This technique has been successfully applied for the electromagnetic modelling of electrical machines and it gives relatively good results as compared to finite element method (FEM). The HAM is based on the coupling of a macro-element, based on the analytical solution of heat equation, for the mechanical air-gap with a mesh based generated lumped parameter thermal model for the rest of the studied structure. In order to validate the proposed modelling approach, results issued for the HAM are compared to corresponding results obtained from a FE analysis. This modelling approach should constitute a useful tool for the pre-design of electrical machines

Etude experimentale des capteurs solaires a air: le sechage de la figue

No Abstract. Technologies Avancees Vol. 17 2005: pp. 15-2

Thermal modelling of tubular linear machines using a hybrid analytical method

The aim of this paper is to apply a hybrid analytical method (HAM) for the thermal modelling of tubular linear machines. This technique has been successfully applied for the electromagnetic modelling of electrical machines and it gives relatively good results as compared to finite element method (FEM). The HAM is based on the coupling of a macro-element, based on the analytical solution of heat equation, for the mechanical air-gap with a mesh based generated lumped parameter thermal model for the rest of the studied structure. In order to validate the proposed modelling approach, results issued for the HAM are compared to corresponding results obtained from a FE analysis. This modelling approach should constitute a useful tool for the pre-design of electrical machines