Search results for "acids"
showing 10 items of 3520 documents
Structures of single, double and triple layers of lipids adsorbed on graphene: Insights from all-atom molecular dynamics simulations
2017
Abstract Non-covalent functionalization of graphene with phospholipids is a promising technique for biosensing applications and intracellular delivery of analytical probes and drugs. However, molecular details of the self-assembly of lipids on graphene surface is still poorly understood and hard to control. There is a clear lack of understanding of why various kinds of lipid aggregates can form on graphene. In the current work, we address this question by investigating equilibrium and dynamical properties of lipid layers adsorbed on graphene in water environment and in vacuum using all-atom Molecular Dynamics simulations. It is shown that a variety of lipid aggregates can form on top of gra…
Streoselective hemisynthesis of heterosubstituted aminoacidsApplication on radiofluorolabeling for peptide imaging.
2017
Stereoselective hemisynthesis of lateral chain heterosubstituted aminoacids.Applications on radiofluorolabeling for peptide imaging.This thesis work, which was carried out at the Institute of Molecular Chemistry of the University of Burgundy and in collaboration with the Institute of Cognitive and Integrative Neurosciences of Aquitaine, focuses on the development of new methods for the synthesis of side chain heterosubstituted amino acids including phosphine containing or silyl groups, as well as on their applications. In a first part, the synthesis of side chain silylated amino acids is achieved without racemization using a key Wittig reaction between a phosphonium salt, derived from L-asp…
Etude du contrôle hédonique de la prise alimentaire par l'analyse des potentiels évoqués gustatifs
2016
Hedonic control of food intake has been studied using neurophysiological investigations in animals and functional imaging in humans. Gustatory evoked potentials (GEPs), a higher time resolution technique than functional imaging, have never been used for this purpose. The first aim of this thesis was to establish a reliable recording of GEPs in humans, in response to a sapid stimulus. The second aim was to determine the GEPs modifications according to the hedonic value of food intake. GEPs recording was performed in response to an intermittent stimulation of a sapid solution in more than 100 young healthy subjects. The comparisons between cerebral recordings in response to water or paraffin …
Role of 24-S-hydroxycholesterol in membrane dynamics during retinal gliosis in glaucoma
2017
International audience; Purpose : Glaucoma is a severe and irreversible ocular disease characterized by progressive optic neuropathy with the loss of retinal ganglion cells (RGC). One of the established causes of RGC apoptosis is Müller Glial Cell (MGC) activation, called “retinal gliosis”. MGC are the most numerous glial cells in the retina and one of their roles is to maintain cholesterol homeostasis. A lack or an excess of cholesterol in neurons can cause neuro-degeneration. Cholesterol 24S-hydroxylase (CYP46A1) is present in RGC where it catalyses the formation of 24S-hydroxycholesterol (24S-OHC), and thereby participates to cholesterol elimination. CYP46A1 is overexpressed during glauc…
Evidence for interactions between aroma compounds and the CB1 receptor: a way to regulate food intake?
2012
National audience; Obesity is a major cause of morbidity and mortality worldwide, characterised by a chronic imbalance of energy homeostasis. The regulation of dietary intake appears to be an effective way to regulate this imbalance. Furthermore, it is now well established that the endocannabinoid system influences appetite via the cannabinoid receptor type 1 (CB1): CB1 agonists can promote food intake while CB1 antagonists tend to decrease appetite (1). Interestingly, recent studies showed that CB1-like receptors are expressed in the olfactory epithelium of Xenopus laevis tadpoles (2). Elsewhere, it has been demonstrated that aroma perception is implicated in the process of satiety (3). Co…
Quantitative analysis of fatty acids on choline- and ethanolamine-phospholipids in human ocular and non-ocular tissues by liquid chromatography/tande…
2011
Quantitative analysis of fatty acids on choline- and ethanolamine-phospholipids in human ocular and non-ocular tissues by liquid chromatography/tandem mass spectrometry (LC-ESI-MS/MS). annual meeting of the association-for-research-in-vision-and-ophthalmology (ARVO)
Dietary n-3 PUFAs affect the blood pressure rise and the cardiac function modulation in a hyperinsulinemia rat model in vivo
2004
National audience; This study was designed to assess in vivo the cardiovascular consequences of a dietary docosahexaenoic (DHA) or eicosapentaenoic (EPA) acid specific intake in a hyperinsulinemia (HI) model presented by fructose-induced insulin-resistant rats. Wistar rat (n=6 in each dietary group of control or HI rats) were fed for two months a diet containing 62% fructose, and supplemented (or not for control, NFD) with either DHA or EPA (240 mg per day). Modifications of the cardiovascular parameters (rise in blood pressure (BP), heart rate (HR), modulation, ECG) were continously monitored using an intra-abdominal implanted telemetry system in HI rats. The myocardial phospolipid fatty a…
Lipase linguale et détection des lipides
2016
Lipase linguale et détection des lipides. Journées francophones de nutrition (JFN)
Increased electron donor and electron acceptor characters enhance the adhesion between oil droplets and cells of Yarrowia lipolytica as evaluated by …
2003
International audience; The adhesion of methyl ricinoleate droplets to cells of the yeast Yarrowia lipolytica was investigated. A new cytometric method, relying on the double staining of fatty globules with Nile Red and of cells with Calcofluor, enabled us to quantify methyl ricinoleate droplet adhesion to cells precultured on a hydrophilic or on a hydrophobic carbon source. In this last case, droplet adsorption was enhanced and a MATS (microbial adhesion to solvents) test revealed that this increase was due to Lewis acid-base interactions and not to an increase in the hydrophobic properties of the cell surface. These preliminary results demonstrate that the developed cytometric method is p…
Influence of Temperature, Solvent and pH on the Selective Extraction of Phenolic Compounds from Tiger Nuts by-Products: Triple-TOF-LC-MS-MS Character…
2019
The aim of this study was to assess the effect of temperature, solvent (hydroethanolic mixtures) and pH on the recovery of individual phenolic compounds from &ldquo