Teses / dissertações sobre o tema "Spectrométrie de masse à faisceau moléculaire"
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Crunelle, Benoît. "Étude de flammes basse pression de méthane et d'éthane par couplage faisceau moléculaire : spectrométrie de masse avec ionisation par impact électronique ou multiphotonique et par modélisation". Lille 1, 1995. http://www.theses.fr/1995LIL10163.
Texto completo da fonteAubry, Olivier. "Étude des précurseurs gazeux de couches minces en carbone déposées à partir de phases gazeuses activées thermiquement et par plasma". Phd thesis, Université d'Orléans, 2002. http://tel.archives-ouvertes.fr/tel-00011968.
Texto completo da fonteBordel, Damien. "Développement de nouveaux substrats compliants pour l'hétérroepitaxie de semiconducteurs". Ecully, Ecole centrale de Lyon, 2007. http://www.theses.fr/2007ECDL0045.
Texto completo da fonteThis work showed how employed a viscous or elastic material in order to make a pseudosubstrate. This allowed to epitaxy new semiconductors that couldn't be obtain without defaults on the standart substrate. We explained the double bonding technic in order to obtain pseudosubstrates. A puedomorphic layer of InGasAs/InAsP/InGaAs strained in compressive was epi-grown onto substrate. This was bonded onto a thick PDMS substrate by hydrophobic-hydrphilic bonding. The PDMS thanks to its great elsticity allowed the relaxation of the epilayer strain. Like the epi-grown of III-V semiconductors was dont to incompatible temperature with the PDMS stability a second bonding on host sunstrate was used. The InGaAs epilayer photolumijnescnce spectrum showed the optoelectronic quality of the re-epitaxy. Others materials were also explored. Once used a self assembled molecular layer in place of PDMS. This layer was used both like adhesif and compliant layer. The second material was a glass, the borophosphosilicate glass (BPSG) that was compatible with III-V semiconductors epi-grown. This allowed to free from double bonding. This study showed the importance of both bonding interface, who permit to divide the strain up between the thin layer and the substrate, and the different thick between the epi-grown layer and the thick compliant layer
Abd, El Rahim Mohamad. "Déflexion électrique d'un jet moléculaire : progrès expérimentaux et théoriques". Phd thesis, Université Claude Bernard - Lyon I, 2005. http://tel.archives-ouvertes.fr/tel-00011199.
Texto completo da fonteDmitriev, Artëm. "Kinetic study of ester biofuels in flames". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0238.
Texto completo da fonteGlobal progress all over the world requires a variety of clean energy sources. Liquid ester-based biofuels seem to be very effective in this context since they are easy to use in modern vehicles, they can be produced from a variety of renewable resources, and they provide environmentally friendly combustion characteristics. In this regard, fatty acid ethyl esters (FAEEs) are considered as a promising class of biofuels. The main goal of this thesis was to develop an updated chemical kinetic mechanism of combustion of light FAEEs up to ethyl pentanoate and validate it against the new experimental data on chemical speciation in low and atmospheric pressure premixed laminar flames. The flames fueled by three FAEEs, ethyl acetate, ethyl butanoate and ethyl pentanoate, were investigated by means of molecular-beam mass-spectrometry and gas-chromatography. More than 40 stable and intermediate species including radicals were detected and quantified in the flames. A comprehensive analysis of the developed mechanism was performed. The thesis consists of 3 chapters. In the first chapter a review of literature is presented. The most important experimental and theoretic studies on FAEEs are discussed. The second chapter presents an overview of experimental and simulation methods used in the work. Details on the mechanism development are also provided in this part. The last chapter present experimental and modeling results on the esters studied in comparison with the literature kinetic mechanisms
Debois, Delphine. "Imagerie moléculaire d'échantillons biologiques par spectrométrie de masse ToF-SIMS". Thesis, Evry-Val d'Essonne, 2008. http://www.theses.fr/2008EVRY0014/document.
Texto completo da fonteMy PhD’s work has been devoted to the development of the emergent technique ToF-SIMS imaging. The first part of my work was dedicated to fondamental aspects with the use of a fullerene ion source as a primary ion beam or sputtering ion beam. We expected to realize 3D imaging. The second part of my work consisted to applications of the mass spectrometry imaging. Several application fields were studied, as archeology as with the analysis of patina of the Dogon statuary or chinese mummy hair. A third project was dedicated to the in situ biomarker research from human liver biopsies. The goal of this study was to identify a potential lipid biomarker of the non-alcoholic fatty liver disease. The last part of this manuscript is devoted to the in situ qualitative and quantitative analysis of surfactins (a family of heptacyclodepsipeptides) on a Bacillus subtilis swarming community. We combined ToF-SIMS imaging for qualitative analysis and localization of surfactins within the swarming pattern and MALDI-TOF mass spectrometry for the quantification of these species. The results ot this PhD’s work show that ToF-SIMS imaging could be applied to various fields of research as archeology, microbiology and medicine
Wolters, Cédric. "Caractérisation moléculaire d’échantillons organiques complexes par spectrométrie de masse et chromatographie en phase liquide". Thesis, Université Grenoble Alpes, 2021. http://www.theses.fr/2021GRALU009.
Texto completo da fonteHow to analyse a complex organic sample? This general question seems simple at first glance but requires a closer look at the notion of complexity to be able to understand and justify the means used to characterise it. In planetology, and more widely in astrophysics, all the observations and observables indicate that the matter that makes up extraterrestrial objects is composed of a mixture of various molecules, and this mixture is more or less diverse and dense depending on the object. Observations and models are routinely done to try to understand these objects and to constrain their evolutionary processes, or to try to investigate their origin.Characterising the molecular complexity of such objects requires state-of-the-art instruments, which are difficult to adapt to space industry constraints in order to be placed on a probe, and this requires that the object under study can be sampled. However, most objects of interest cannot be reached in a reasonable time. Therefore, another way to study these objects is needed: laboratory astrophysics. Many experiments attempt to simulate the objects and environments in which they evolve and analyse the evolution of matter subjected to these constraints. Part of the challenges of these experiments lies in the chemical characterisation of the samples, and more particularly in their molecular characterisation.As part of this thesis, we proposed to use high-resolution mass spectrometry (HRMS) and high-performance liquid chromatography (HPLC) to characterise complex organic samples. To do so, the entire analytical chain was studied, from the data acquisition to its use. Thus, we proposed an optimisation of the data acquisition in Orbitrap, as well as the systematic processing of the data resulting from the analysis done by ESI-HRMS as well as for the analysis done by LDI-ICR. Chromatography coupled with mass spectrometry is a powerful tool for accessing the molecular structure of samples and requires developing methods that are suited to the samples analysed. Therefore we offered two HPLC methods for sample analysis, which have been developed and validated for the analysis of complex samples. However, no currently available commercial software allowed for the unsupervised analysis of such samples. Software to allow the processing of this data has now been developed and allows the molecular diversity of samples to be revealed without supervision. The identification of the detected molecules is not an easy process since it then requires having all the possible isomers for each molecule detected as standards for reference. To reduce the number of possibilities, a tool for predicting retention times was proposed. This was based on knowledge of the physico-chemical properties of known compounds to predict their theoretical retention time on the methods used.Lastly, this work presents the application of all the developments carried out during these three years on a set of samples of synthetic atmospheric aerosol analogues modelling exoplanets of the super-Earth and mini-Neptunes type. From the analysis of their soluble matter to the comparison between soluble, insoluble, and total phase, analysis by mass spectrometry indicates a great diversity and important differences between samples. This indicates processes of formation and evolution related to the composition of the reactive mixture. Finally, chromatographic analysis of one of these samples indicates multiple isomers, some of which may be labelled as biological molecules, potentially involved in the process of the origin of life
Lianos, Leonardos. "Application du SIMS TOF à l'étude moléculaire et structurale de surfaces de polymères". Lyon 1, 1994. http://www.theses.fr/1994LYO10116.
Texto completo da fonteKamalou, Omar. "Faisceau d’agrégats chargés sélectionnés en taille : réalisation et premières expériences". Caen, 2007. http://www.theses.fr/2007CAEN2011.
Texto completo da fonteThe main objective of this work concerns the production of beams of mass-selected clusters of metallic and semiconductor materials. Clusters are produced in a magnetron sputtering source combined with a gas aggregation chamber, cooled by liquid nitrogen circulation. Downstream of the cluster source, a Wiley-McLaren time-of-flight setup allows to select a given cluster size or a narrow size range. The pulsed mass-selected cluster ion beam is separated from the continuous neutral one by an electrostatic 90°-quadrupole deflector. After the deflector, the density of the pulsed beam amounts to about 103 particles/cm3. Preliminary deposition experiments of mass-selected copper clusters with a deposition energy of about 0. 5 eV/atom have been performed on highly oriented pyrolytic graphite (HOPG) substrates, indicating that copper clusters are evidently mobile on the HOPG-surface until they reach cleavage steps, dislocation lines or other surface defects. In order to lower the cluster mobility on the HOPG-surface, we have first irradiated HOPG samples with slow highly charged ions (high dose) in order to create superficial defects. In a second step we have deposited mass-selected copper clusters on these pre-irradiated samples. The first analysis by AFM techniques showed that the copper clusters are trapped, on the defects produced by the highly charged ions
Madec, Edwige. "Analyse moléculaire d'une protéine-kinase, PrkC, et d'une phosphatase, PrpC, impliquées dans deux processus de développement chez Bacillus subtilis". Paris 11, 2002. http://www.theses.fr/2002PA112283.
Texto completo da fonteProtein phosphorylation on Ser/Thr/Tyr residues plays a vital role in many cellular processes. My studies in this Thesis concerned the characterization, for the first time of PrkC, a membrane linked protein kinase in Bacillus subtilis, belonging to the super-family of Hanks kinases, predominantly found in eukaryotes. PrkC was shown to be an integral membrane protein with the topology of some receptor kinases found in humans, with an external domain presumed sensor, a single transmembrane domain (TMD) and a highly conserved kinase domain. I have shown that PrkC forms dimers with both the extracellular domain and the TMD capable of promoting dimerization. In the presence of ATP, PrkC or its catalytic domain, PrkCc, autophosphorylates in vitro and phosphorylates MBP. In both cases, phosphorylation involves one or more Thr residues. In collaboration with Ole Jensen (Danemark), we were able to identify precisely eight phosphorylated residues in PrkC by mass spectrometry. These residues were localised to specific regions of a 3D structure of PrkCc modelled on known kinase structures. Four Thr were localised to the activation loop whereas three Thr are in the juxtamembrane region, and one Ser in a non conserved region. Site directed mutagenesis of these residues confirmed that autophosphorylation of Ser214 and the threonine residues in the activation loop is essential for kinase activity. In a complementary approach, PrpC, a protein phosphatase homologue of the human PP2C family was also characterized. The autophosphorylated form of PrkC was dephosphorylated by PrpC. PrkC and PrpC are encoded by adjacent genes which are co-transcribed. These results indicate that these enzymes form a functional protein kinase/phosphatase couple. Moreover, other studies showed that mutants deleted for prkC or prpC displayed reduced biofilm formation and sporulation frequencies. A better understanding of the role of PrkC and PrpC in the cell requires identification of targets/partners
Cazaubon, Bertrand. "Étude par spectrométrie de masse quadripolaire d'un jet pulsé d'oxygène atomique et de son interaction avec les matériaux". Toulouse, ENSAE, 1996. http://www.theses.fr/1996ESAE0012.
Texto completo da fonteMériaux, Céline. "Imagerie du système nerveux central par spectrométrie de masse MALDI". Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10059/document.
Texto completo da fonteIn recent years, MALDI mass spectrometric imaging has proved to be a powerful tool for biomarker research. This technology allows the analysis of a wide range of endogenous and exogenous compounds in tissue sections. Many developments need to be undertaken to improve the detection of molecules. The sample preparation, including chemical treatment and deposition of the matrix, is dependent on the tissue and molecules of interest and influences the quality of spectra and images. In addition, the bioinformatics tools such as multivariate analysis provide informations on the markers according to phenotypes. These steps are crucial for imaging applications in the field of biology. First of all, we focused on the development of new matrices suitable for MALDI imaging such as ionic matrices. Secondly, these developments have been applied to the invertebrate model, the medicinal leech, at embryonic and adult stages, to compare the biological mechanisms involved in the establishment of the central nervous system and nerve regeneration after injury of this system. Finally, studies of neurological damage have been undertaken to understand the key factors involved in the balance regeneration/degeneration. Thus, studies of human hippocampi samples have revealed the existence of proteins associated with a particular distribution corresponding to layers of neurons abnormally present in the hippocampus of epileptic patients
Fougère, Laëtitia. "Signature moléculaire de milieux complexes : Stratégie de couplage à la spectrométrie de masse et interprétation des données". Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE2014.
Texto completo da fonteThe metabolite composition of living organisms changes when they are subjected to environmental modification and differs from one species to another. The aim of this PhD thesis was to deploy different chromatographic coupling strategies with mass spectrometry and MS data processing in order to respond in the most relevant way to the various problems encountered in terms of characterization, quantification and comparison of the molecular content of complex samples.Firstly, these studies led to the development of TLC/MS dereplication methods to rapidly identify known molecules and to evaluate the composition of samples. In order to improve and standardize the comparison of different samples, image processing of TLC plates were performed and statistical studies were applied. In addition, the hyphenation TLC/MS have been developed to identify different low molecular mass families (flavonoids, steroids). In a second way, a methodology was implemented in UHPLC/HRMS to characterize the presence of C and O-glycosyl flavonoids in corn silk samples of five different varieties and help in the varietal selection to fight against pest infestation. Visual representation approaches of molecular content were used to target the molecules of interest which were they were quantified by UHPLC/MRM MS. The different chromatographic fingerprints were then compared using statistical treatments in order to highlight the differences between these five varieties and thus to identify the molecules allowing this distinction
Chevreux, Guillaume. "Etude des interactions moléculaires spécifiques par spectrométrie de masse : application à la chimie du vivant". Université Louis Pasteur (Strasbourg) (1971-2008), 2005. https://publication-theses.unistra.fr/public/theses_doctorat/2005/CHEVREUX_Guillaume_2005.pdf.
Texto completo da fonteThe development of new soft ionization methods at the early nineties provided new insight in the application range of mass spectrometry. Thus, the new ionization technique called “electrospray” showed rapidly that it was well fitted for the analysis of biological macromolecular entities such as proteins. Moreover, first studies reported that supramolecular complexes in solution could be transferred intact in the gas phase of the mass spectrometer, allowing their study by mass spectrometry. The aim of this work is to explore the potential of electrospray ionization mass spectrometry for the study of non covalent complexes in the biological field. We have first developed instrumental conditions and methodologies allowing the discovery of new drugs. In this context, mass spectrometry rapidly appeared as a fruitful technique allowing the characterization of specific protein/ligand interactions. The main application consists in the validation of hits after high throughput screening applied on a therapeutic target. In a second part, we studied biological mechanisms based on various binding partners. The protein function in vivo is modulated by host/guest mechanisms implying non covalent molecular interactions. The accurate characterization of such binding partners, using mass spectrometry, was very useful for the comprehension of complex biological mechanisms such as the cellular motility, the adhesion process or the oxidative stress. In a last part, we used real time resolved mass spectrometry to explore the dynamic of non covalent complexes (subunit exchange, ligand dissociation). With this approach, it was possible to reach kinetic data such as dissociation constant, thus providing new perspectives for the characterization and understanding of biological complexes
Hannewald, Paul. "Etude de l'interaction médicament/récepteur par spectrométrie de masse : mise en place et validation de nouveaux protocoles de criblage moléculaire". Thesis, Metz, 2008. http://www.theses.fr/2008METZ042S/document.
Texto completo da fonteDiscovering new drugs by biomolecular screening is a central task of pharmaceutical research. Mass spectrometry, as a reliable, reproducible, sensitive and specific technique, compatible with a wide range of samples and offering an excellent throughput, shows its potential in different strategies of research and development. The aim of this work was to develop and validate a new strategy, involving matrix assisted laser desorption/ionization coupled to time of flight mass spectrometry (MALDI-TOFMS) to screen the ability of different compounds, including plant extracts, to bind to two biological targets (tubulin and DHFR). The protocol is therefore divided into three main steps : an incubation of the compounds to be tested with target, an elimination of all unbound compounds and the MALDI-TOFMS detection of target-bound compounds. Our protocol was validated and the results that can be obtained were discussed. The throughput offered by this technique was evaluated as 60 samples in 1h50 to 3h30, or 18 to 32 samples per hour. Finally, we developed a new approach to perform a secondary screening of active compounds. The protocol was applied to screen crude plants extracts (colchicum autumnale, catharanthus roseus and green tea) and allowed to find 20 tubulin-binding or DHFR-binding molecules, and the relative affinity of one of these was also evaluated
Chassaigne, Hubert. "Caractérisation moléculaire des complexes des métaux et des métalloi͏̈des avec les bioligands par la spectrométrie de masse à source d'ionisation électrospray (ESI MS/MS)". Pau, 1999. http://www.theses.fr/1999PAUU3017.
Texto completo da fonteLe, Rhun Émilie. "Recherche de biomarqueurs protéiques dans le but de réaliser une classification moléculaire des gliomes : étude GLIOMIC". Thesis, Lille 2, 2017. http://www.theses.fr/2017LIL2S005/document.
Texto completo da fonteThe annual incidence of gliomas is estimated at 6.6 per 100,000. Suvival varies profoundly by type of glioma, with 5-year survival rates of 48% for World Health Organization (WHO) grade II diffuse astrocytoma, 28% for WHO grade III anaplastic astrocytomas, 80% for WHO grade II oligodendroglioma, 52% for WHO grade III anaplastic oligodendroglioma and 5% for WHO grade IV glioblastoma, the most frequent primary malignant brain tumor. A better understanding of the molecular pathogenesis and the biology of these tumors is required to design better therapies which can ultimately improve the prognosis of patients. The WHO 2016 classification of central nervous system tumors has for the first time integrated molecular data with the histopathological data, in order to improve the classification of the different subgroups of central nervous system tumors and to allow to derive more specific therapeutic strategies for each of the different subgroups.In the present work, we aimed at evaluating the value of a proteomic approach using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry coupled with microproteomic analysis in gliomas through the GLIOMIC clinical study (NCT02473484), we aimed at obtaining a molecular classification of glioblastomas by integrating clinical data to the ones obtained by such technologies. The feasibility of this approach was first demonstrated in a cohort of anaplastic gliomas. In this first analysis, we showed that although proteomic analysis confirmed the heterogeneity of brain tumors already observed with the histological analysis, the two approaches may lead to different and complementary information. Three different groups of proteins of interest were identified: one involved in neoplasia, one related to glioma with inflammation, and one involved neurogenesis. Then, analyses of glioblastomas confirmed the three proteomic patterns of interest already observed in the anaplastic gliomas, which represents new information as compared to histopathological analysis alone. These results have to be confirmed in a larger cohort of patients.We conclude that MALDI mass spectrometry coupled with microproteomic analysis may provide new diagnostic information and may aid in the identification of new biomarkers. The integration of these proteomic biomarkers into the clinical data, histopathological data and data from molecular biology may improve the knowledge on gliomas, their classification and development of new targeted therapies
Seng, Piseth. "Application de la spectrométrie de masse MALDI-TOF en microbiologie clinique". Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM5033/document.
Texto completo da fonteThe objective of this thesis is to apply the method of bacterial identification by MALDI-TOF MS in daily practice in a routine clinical microbiological laboratory. Firstly, we prospectively evaluated the performance and the cost-effective of bacterial identification by MALDI-TOF in comparison with conventional phenotypic identification methods. During a 16-week study, we compared the performance of MALDI-TOF with conventional techniques of identification including Gram staining, API ANA identification strip and automated identification using the Vitek 2. The unmatched identifications between MALDI-TOF and conventional methods were resolved by molecular identification. In this study, we showed that MALDI-TOF was an effective tool and less expensive for the rapid identification of bacterial species in clinical microbiology laboratory. MALDI-TOF can be used in first intention for identification before Gram staining or other phenotypic identification techniques based on physicochemical properties of bacteria. Secondly, we retrospectively evaluated the performance and the cost-effectiveness of the exclusive use of MALDI-TOF in bacteriological diagnosis in comparison with conventional phenotypic identification. 11-year retrospective analysis of data showed that MALDI-TOF was efficient and completely adapted for the routine identification of bacterial species. We also showed that MALDI-TOF had capacity to identify bacterial species that were rarely involved in human diseases. This technique could be an alternative to molecular methods in the clinical laboratory
Bertherat, Marc. "Étude par spectrométrie de masse à détente supersonique du dégazage des bains d'aluminium liquide". Grenoble INPG, 2000. http://www.theses.fr/2000INPG0020.
Texto completo da fonteCapron, Michael. "Étude de l'interaction entre ions multichargés et systèmes complexes d'intérêt biologique : effets de l'environnement à l'échelle moléculaire". Phd thesis, Université de Caen, 2011. http://tel.archives-ouvertes.fr/tel-00741879.
Texto completo da fonteVenisse, Nicolas. "Procédure de recherche large ("screening") de xénobiotiques dans le sérum par chromatographie liquide - électrospray - spectrométrie de masse, appliquée à la toxicologie humaine". Bordeaux 2, 1999. http://www.theses.fr/1999BOR2P071.
Texto completo da fonteDelaunay, Rudy. "Croissance moléculaire dans des agrégats d’hydrocarbures aromatiques polycycliques induite par des collisions avec des ions". Caen, 2016. https://tel.archives-ouvertes.fr/tel-01640994.
Texto completo da fonteCazier, Hélène. "Développement d’une nouvelle approche combinant la radioimagerie et l’imagerie par spectrométrie de masse pour l’analyse de nanoparticules". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS399.
Texto completo da fonteThe vectorization of drugs, which allows them to be transported to target tissues to increase their pharmacological activity while limiting their toxicity and adverse effects, is a rapidly expanding research area in which nanotechnologies are one of the key factors. One of the challenges in this thesis was therefore to develop a combined imaging method between MSI and imaging β for the study of the biodistribution of graphene-type nanoparticles. Despite the study of heterogeneous nanoparticles, the analyses determined a repeatable carbon signature of graphene oxide in LDI - MS analysis and reproducible MSI analyses with CVs below 30%. In addition, the combination of the two techniques made it possible to obtain the absolute quantification of GO in radioimaging after exposure of mice to three injection doses as well as the biodistribution at 25 µm of spatial resolution of these nanoparticles within tissues thanks to the contribution of MSI. In a second project to study polymeric micellar vectors encapsulating a drug, a MALDI - TOF method was also developed to detect these two molecules simultaneously. However, the experiments carried out have shown the need to develop tissue treatment protocols compatible with MSI and making it possible to improve the sensitivity threshold of this analytical technique
Thomas, Sébastien. "La fragmentation moléculaire : modèle statistique et réduction par plasma de l’acétone avec identification en ligne des produits". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS559.
Texto completo da fonteMolecular fragmentation is a promising technique for the treatment of polluted gaseous effluents. This work deals with the theoretical and experimental study of the reduction of VOC chemical pollutants by fragmentation. We have transformed an atomic nucleus and cluster fragmentation model, redesign at CSNSM, into a model that treats any type of molecules (SMF moldel). The efforts have been focused on accelerating the computation of the weights with multivariate incomplete Beta functions (factor 30 on speed), on the interfacing with the Gaussian ab-initio software, on the generalization of the molecular formalism as well as on molecular rearrangements. To account for the characteristics of our experimental setup (reactivity between fragmentation and detection) the results were processed by a 0-D chemical kinetics model. Predictions on acetone fragmentation were then compared to our experimental results obtained using an innovative device. Acetone degradation was carried out in a homogeneous plasma reactor, developed at LPGP, to guarantee the uniformity of the reaction conditions. To measure the large number of discharge by-products, we used a new detection method developed at LCP: compact FT-ICR mass spectrometers producing in situ real-time measurements. This new experimental device has been successfully implemented. It allowed the fine study of the acetone excitation - de-excitation - oxidation mechanisms and the validation of the theoretical predictions
Dodeller, Marc. "Analyse par spectrométrie de masse de l'oxygène moléculaire singulet et de protéines potentiellement ciblées au sein de cellules tumorales lors de la thérapie photodynamique". Metz, 2007. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2007/Dodeller.Marc.SMZ0753.pdf.
Texto completo da fontePhotodynamic therapy (PDT), uses a photosensitizing molecule such as 5,10,15,20-tetrakis(m-hydroxyphenyl) chlorin (m-THPC, Foscan®), a second generation drug which is specially targeted tumoural tissue with a good selectivity, light and oxygen, inducing cell death by necrosis or apoptosis. Firstly, our studies consist to detect by MALDI-TOF/MS, in intact HT29 cells (adenocarcinoma human colon), singlet oxygen generated by Foscan® (Biolitec Pharma Ldt, Dublin, Irlande) and the protein cells distribution after PDT treatment. A MALDI-TOF mass spectrometer was used to highlight ortho-benzoïbenzene (o-BB) resulting from the reaction between singlet oxygen generated by Foscan® during PDT treatment and 1,3-diphenylisobenzofurane (1,3-DPBF, a specific singlet oxygen quencher). This technique allows the following of the in situ behaviour of the photosensitizer and to detect the presence of singlet oxygen directly in intact HT29 cells. We have also studied the oxidative stress induced by PDT treatment on HT29 cells. After 2D gel SDS-PAGE step in order to observe the protein distribution, proteomic approach is carried out by MALDI-FTICR mass spectrometry (9,4 T, Ion Spec Varian, California). Thnaks to ImageMaster 2D platinium software, we are able to visualize under expression of some proteins. The proteinic finger printings is then characterized by MALDI-FT-ICR/MS and the first results indicate that proteins of dislfide Isomerase family should be implied in PDT processes. MALDI-TOF/MS and MALDI-FTICRMS (9,4 T) appear to be a sensitive and reliable analytical tool (add to UV/Visible anf fluorescence spectroscopy) for the mechanism of PDT understanding
Poully, Jean-Christophe. "Spectroscopie infra-rouge et spectrométrie de mobilité ionique appliquées aux structures de systèmes moléculaires chargés isolés d'intérêt pharmaceutique". Paris 13, 2009. http://www.theses.fr/2009PA132024.
Texto completo da fonteStructural properties and noncovalent interactions within biologically relevant molecular systems are crucial for their activity. They are especially important for the specific binding of drugs on receptors in living organisms. Besides, studying molecules in the gas phase allows measuring their intrinsic properties because of the absence of solvent effects. Precise information can then be extracted from the comparison between experimental data and state-of-the-art quantum chemistry calculations. Our research group aims to describe the structural changes occurring within peptides, oligonucleotides and pharmaceutically relevant complexes: we compare results from simulations and two complementary experimental techniques, IRMPD spectroscopy and ion mobility spectrometry. In this PhD thesis, I have tested for the first time the performances of a QM/MM method for the simulation of the IR spectra of isolated biomolecular systems. It allowed me to simulate the IR spectrum of amyloid β-protein strands containing more than 250 atoms. We found that the solvent in which these strands are diluted has a big influence on their gas-phase secondary structure: in the case of polar solvents, globular ones dominate, whereas a weak dielectric constant tends to favor helical structures. The structural changes upon receptor binding on vancomycin, a glycopeptide antibiotic, have also been studied. The receptor binding site in the protonated complexes is not the pocket which can be seen in X-ray scattering data, but the specific interactions responsible for the high binding constant of the complex in solution remains intact in the deprotonated species
Bierla, Katarzyna. "Approches analytiques pour la quantification par spectrométrie de masse élémentaire et moléculaire du sélénium total, des acides aminés et métabolites séléniés dans les matériaux biologiques". Pau, 2008. http://www.theses.fr/2008PAUU3003.
Texto completo da fonteThe thesis presents methodological developments and solutions to several problems concerning the analysis of biological samples for the concentration of the total selenium and its species. As a contribution to the methodology for the total Se determination, the use of Xe as a non-reactive collision gas was proposed to eliminate the polyatomic interferences in Se detection by ICP MS. This allowed anaccurate determination of Se isotope ratios without mathematical correction. The principal part of the thesis concerns the development of methods for the quantitative determination of the Se-aminoacids (selenomethionine (SeMet), selenocysteine (Secys)) in animal blood, soft tissues and milk. The methods developed are based on the quantitative carbamidomethylation of SeCys and SeMet followed by their proteolytic release from proteins. The fraction isolated by size-exclusion chromatography was submitted to ion-paring HPLC - ICP MS analysis. In terms of contribution to speciation analysis of Se-rich plants, the work proposes a sequential extraction scheme allowing the recovery of Se from garlic. Se in Se-enriched garlic was fractionated by a sequential procedure including leaching with water, lysis, proteolysis, leaching with HCI, sulfite and CS and, finally, digestion of the residue. A strategy for the standardless identification of unknown water-soluble low-molecular weight Se metabolites by molecular mass spectrometry is pursued for monkeypot nuts. The use of size-exclusion, cation-exchange and ion-paring reversed-phase HPLC allowed the purification of selenocystathionine and its y-glutamyl-derivatives to a degree allowing their formal identification by organic mass spectrometry
Delcambre, Adéline. "Une approche moléculaire de l'astringence des vins : utilisation de sondes pour l'étude des interactions entre protéines de la salive et polyphénols". Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14124/document.
Texto completo da fonteAstringency is a pucker or dry mouth sensation, typically experimented with red wine tasting, that finds its origin in the complexation of polyphenols with salivary proteins, producing a reduced lubrication of the oral cavity. Among salivary proteins, proline rich proteins (PRPs) are well known for their capacity to bind and precipitate dietary polyphenols. A better knowledge of this phenomenon at the molecular level is required in order to master it. A 14 amino acid stretch from the PRP IB7 has been synthesized and shown to be a representative mimic of PRPs. Previous work by Energy Resolved Mass Spectrometry (ERMS) allowed characterizing the keys parameters of the interactions between these polyphenols and the IB714 probe. An affinity scale in the gas phase was determined in this way. However, the ERMS approach was hardly compatible with the complexity of wine polyphenols, and a validation of the affinity scale in condensed phase was required. Thus, we designed a new strategy relying on the use of molecular probes immobilized on magnetic beads. A peptidic probe was obtained by grafting the synthetic IB714 peptide on magnetic beads bearing carboxylate functions, and used to study its interaction with model polyphenols. After magnetic precipitation of the beads, unbound polyphenols left in the supernatant were quantified by mass spectrometry using an internal standard. An affinity scale in liquid phase was established in this way. Relative positions of model polyphenols on this latter scale were similar to those determined by ERMS. A polyphenolic probe was obtained by grafting a model polyphenol on beads bearing amine functions. This probe has been used to study the interaction with IB714. To prepare further work on more complex mixtures, attempts were made to fractionate human saliva; this allowed eliminating amylase, the major salivary protein. Wine tannins were also fractionated, in order to isolate condensed polyphenols that are characterized by mass spectrometry. The peptidic probe is the molecular tool that offers the best perspectives for future work
Quiles, Anita. "Construction d'une chronologie absolue pour la 18eme dynastie de l'Egypte ancienne par la méthode du carbone 14 en Spectrométrie de Masse par Accélérateur : modélisation bayesienne et simulations de transport de faisceau". Paris 7, 2011. http://www.theses.fr/2011PA077080.
Texto completo da fonteRadiocarbon dating is a well-tried method and a fundamental tool for archaeology. In the first part of this Project, we were interested in the instrumental aspect of measurements done on the ARTEMIS facility at the LMC14 laboratory. At first, we detailed how this facility operates. Then, we used complementary tools to simulate the transport of the beam through the different elements. Using the Transport tool, we obtained the optical spectrum of the beam, ensuring that there was no loss of beam, and identified the most sensitive points of the facility. Then, we used the GEANT4 tool-kit to simulate the interactions of the incident ions in different media. From these simulations we were able to establish the tolerances of the settings on electric and magnetic fields as well as the acceptance of the beam. Finally, the detector was optimized so as to subtract molecular ions C13H and C12H2 from the measurement of 14C ions. Next we showed that Bayesian statistics were a method that was relevant to the improvement of the precision of the results. We particularly focused our experiments on objects from the 18ft dynasty in Egypt. Objects conserved in the Dept. Of Egyptian Antiquities at the Louvre Museum and archaeologically attributed to a specific reign, were dated by radiocarbon analysis. The ages we obtained were constrained by archaeological and astrophysical evidence. We deduced a realistic range of dates for the beginning of each reign of the 18* dynasty. Finally, this new absolute chronology was tested on a specific study of objects coming from Gebel el-Zeit
Lafage, Christian. "Technique d'échantillonnage par faisceau moléculaire couplée à un réacteur à écoulement rapide et à un spectromètre de masse : réalisation et application à l'étude cinétique de la réaction H + IC4H10->produits". Lille 1, 1985. http://www.theses.fr/1985LIL10043.
Texto completo da fonteBarthélemy, Nicolas. "Protéomique qualitative et quantitative, une passerelle pour relier l’expression génomique à la construction des édifices biologiques : Application à la compréhension de la structure moléculaire du cheveu humain". Strasbourg, 2011. https://publication-theses.unistra.fr/public/theses_doctorat/2011/BARTHELEMY_Nicolas_2011.pdf.
Texto completo da fonteHair fiber is a sophisticated biological material for which the details of its molecular structure failed to be well understood because of the lack of data regarding protein expression and organization. In this context, improvement on human hair cells knowledge with proteomic approaches has been performed in this PhD. This work has been structured in four parts : establishment of the knowledge on hair biology and its molecular structure obtained by literature mining. Development of a well-suited proteomic strategy for the special case of hair proteins analysis. This strategy is mainly based on the improvement of nanoLC-ESI-Q-TOF coupling for high-throughput peptide sequencing. Cell type isolation to study the proteome of cortical and cuticular hair cells. We have compared the semi quantitative expression of the identified proteins to investigate their location in those proteomes. These analyses led to protein expression evidence for 60% of keratin associated proteins predicted genes (KAP) compared to the only 20% previously evidenced (according to Uniprot). Use of complementary approaches to attempt to refine the quantification of the major proteins of cortical cells, to evidence structural properties for specific protein sequences and to propose hypotheses for the main KAP genes origin
Climen, Bruno. "Étude des mécanismes de désexcitation de C60 : inonisation retardée et émission C2". Lyon 1, 2006. http://tel.archives-ouvertes.fr/docs/00/09/28/29/PDF/These_CLIMEN.pdf.
Texto completo da fonteThis thesis is dedicated to the study of C60 fullerene cooling mechanisms after a nanosecond laser excitation. In this temporal mode, absorbed energy is redistributed to all cluster’s degrees of freedom causing a fragmentation cascade by emission of C2 molecules. A process of delayed ionisation is highlighted for each size of produced clusters. Then the formed cations can fragment by emission of C2. Our experimental device is made of a time-resolved velocity-map imaging spectrometer combined with a Wiley-McLaren time-of-flight mass spectrometer. It allows extracting the kinetic energy spectra from the photoelectrons or photoions that result from the C60 relaxation chain. These spectra are compared with a statistical model based on Weisskopf’s formalism. A Monte Carlo algorithm was developed in order to rebuild the C60 time-of-flight spectrum. The information extracted from simulations, like the internal energies or the branching ratios at each decay stage, perfectly complete the analysis of the involved processes
Descatoire, Cédric. "Conception, fabrication et caractérisation de sources d’électronébulisation micro et nanofluidiques en technologie silicium". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10156/document.
Texto completo da fonteProteomics, i.e. study of three-dimensional structure of proteins encoded by genome and their alterations under the influence of environment, diseases and drugs, is of great interest for the scientific community. Understanding of changes in proteins expression is an important challenge as they can be used as a biological indicator for illnesses and drug therapeutic effects estimation. But nowadays, only few of them have been characterized, their considerable number requiring faster analysis, with the development of devices compatible with automation and integrating numerous functions: lab on a chip (LOC). Mass spectrometry appears to be the most powerful tool for proteomics researches. It relies on ionisation of a liquid by an electrospray source emitting tiny droplets collected by a mass spectrometer which carries out proteins identification. However, usual sources suffer from numerous drawbacks: poor control of dimensions, incompatibility with automation and LOC. In this context, we have made use of micro and nanotechnologies for new low cost miniaturized silicon sources mass fabrication, integrable in LOC. Characterizations show that these sources are more sensitive and a thorough study of droplets emission is suggested in order to enhance electrospraying control with the aim of other applications as direct writing by nanolithography
Longuespée, Rémi. "Histologie moléculaire : développements et applications pour la recherche de biomarqueurs du cancer de l’ovaire". Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10045/document.
Texto completo da fonteEpithelial ovarian Cancers (EOC) are amongst the most deadly gynecological neoplastic afflictions in western countries. As this time, there is no method for the efficient screening of the disease in its early steps of development. The topics of this PhD are based on two objectives related to biomarkers research of EOC. The first one was the development of analytical methods for MALDI Mass Spectrometry for global biomarkers screenings in different types EOC. An extraction procedure for high molecular mass proteins on tissue sections has been designed in order to push back the limits of sensitivity of the method. Then, multivariate analyses allowed us to compare spectral informations contained in histological regions of different natures. All these developments conducted to the histopathological validation of a biomarker of immunosupression associated to ovarian cancer, namely the C-terminal fragment of PA28 (Reg-Alpha). Another issue, the determination of EOC origin, has also been studied. The second goal of this PhD has been the exploration of the relative implication of the different members of proproteine convertases (PCs) in EOC, which are keys enzymes involved in the maturation of many molecular actors of tumoral progression. To do so, SKOV-3 cell lines have been knocked-down for different PCs to study the functional redundancy of these enzymes. It has then been possible to determine, in cellulo and in vivo, that PACE4 is particularly influent on ovarian cancer progression
Poully, Jean Christophe. "Spectroscopie IR et spectrométrie de mobilité ionique appliquées aux structures de systèmes chargés isolés d'intérêt pharmaceutique". Phd thesis, Université Paris-Nord - Paris XIII, 2009. http://tel.archives-ouvertes.fr/tel-00465057.
Texto completo da fonteThion, Laurent. "Nouvelles approches en génomique structurale adaptées à l'étude d'interactions acides nucléiques/protéines". Toulouse 3, 2002. http://www.theses.fr/2002TOU30225.
Texto completo da fonteNucleoproteic complexes are major determinants of gene expression regulation. The analysis of the relationships between their structure, their dynamics of assembly and their function benefits from the recent and complementary developments of mass spectrometry, bioinformatics and biotechnologies. Our main objective has been to use several of these methodologies - MALDI Tof mass spectrometry, homology modeling and molecular docking - in conjunction with circular dichroism and various molecular biology techniques, to shed light on the molecular mechanisms involved in HIV replication and nervous cells tumorigenesis. We have shown that structural peptide motifs, derived from the double-stranded RNA-binding domain of the human cellular protein TRBP, are able to inhibit the binding of HIV Tat and Rev proteins on their respective TAR and RRE RNA targets. These peptides thus appear as potential mixed inhibitors of the two major regulation pathways of HIV replication. Using circular dichroism, we have shown an increase in the alpha-helical content of the DNA-binding domain of the neuronal transcription factor N-Oct3 when binding to DNA targets in neuronal promotors. MALDI-Tof mass spectrometry coupled to trypsic digestion has allowed us to locate this conformational change in a flexible loop within the domain. This structural information was used to validate the three-dimensional model of the complex between N-Oct3 and its DNA target. We suggest a mechanism which is both specific to a certain type of neuronal promotors and critical in terms of nervous cells tumorigenesis. .
Verruno, Marina. "Investigation of the enhancement of the performance of the SIMS instruments". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS400/document.
Texto completo da fonteSecondary ion mass spectrometry (SIMS) instruments need to be improved in order to satisfy the demands of trends in many fields that require analytical tools that can map samples with both excellent resolution and high-sensitivity chemical information, but also with shorter time of analysis. The objectives of this thesis are: investigate the enhancement of the mass resolution of double focusing mass spectrometers by replacing the standard spherical sector with a novel spheroid geometry which has better focusing properties, and to investigate the reduction of the time of analysis in imaging SIMS by the proof-of-concept of the SIMS multi-ion- beam system.A comparison of the main focusing properties of the spherical sector, the spheroid geometry and a hybrid spheroid geometry, was made using the SIMION software. A comparison in a Nier-Johnson configuration between the spherical sector and the spheroid, showed that the beam presents a rotation of 90° at the exit of the magnet harming the mass resolution in the spheroid configuration. By adding an electrostatic element that can rotate the beam 90° the performance of the mass spectrometer could be improved. However, a comparison of the performances between the spherical and hybrid sectors simulated in a Mattauch-Herzog configuration, showed that when the double focusing condition is properly satisfied, better mass resolution could be achieved with the spheroid geometry.A multi-ion-beam system was investigated for SIMS analysis. A simulation through the secondary optics of a Cameca IMS XF showed successful transmission of nine beams through the optics resulting in nine well focussed spots on the multi channel plate (MCP) detector. The proof-of-concept was completed experimentally in the Cameca IMS 6F, where a multi-hole aperture was mounted in the primary column generating 9 and 16 beams of sizes between 4 μm to 10 μm. Images of an AlCu grid were obtained when t the multi-ion-beam system was scanned over the sample. These results showed that the multi-ion-beam system is a feasible technique for imaging SIMS and by optimizing the design multi-nano-ion-beams will be a solution for reducing drastically the time of analysis
Lattouf, Elie. "Etude expérimentale de la formation de l’ion d’hydrogène négatif lors de collisions entre un ion positif et une cible atomique ou moléculaire". Caen, 2013. http://www.theses.fr/2013CAEN2075.
Texto completo da fonteThe formation of the negative hydrogen ion (H–) in collisions between a positive ion and a neutral atomic or molecular target is studied experimentally at impact energies of a few keV. The doubly-differential cross sections for H– formation are measured as a function of the kinetic energy and emission angle for the collision systems OH+ + Ar and O+ + H2O at 412 eV/a. M. U. These H– ions can be emitted at high energies (keV) in hard quasi-elastic two-body collisions involving a large momentum transfer to the H center. However, H– anions are preferentially emitted at low energy (eV) due to soft many-body (> 2) collisions resulting in a low momentum transfer. The formation of H– ions by electron capture follows excitation or ionization of the molecule. The molecular fragmentation dynamics is modeled to simulate the emission of H– ions. The overall good agreement between the simulation and the experiment leads to the understanding of most of the experimental observations
Fox, ramos Alexander. "Exploration de la diversité chimique des Apocynaceae par la technique des réseaux moléculaires : de la création d’une base de données vers l’annotation in silico". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS543/document.
Texto completo da fonteMonoterpene indole alkaloids (MIAs) constitute a class of natural products that has been extensively studied due to its important pharmacological and therapeutic potentials, and to its large structural diversity. Dereplication techniques based on liquid chromatography coupled to tandem mass spectrometry have recently evolved, with the implementation of molecular networking-based approaches.In this context, we have created a spectral database that encompasses the averaged tandem mass spectra of 172 reference MIAs, in collaboration with several pharmacognosy research teams around the world. This database, named MIADB (standing for Monoterpene Indole Alkaloids DataBase), was made publicly available and can be used as a reference in the application of molecular networking as a dereplication strategy. Thereafter, we used the MIADB to carry out the phytochemical investigation of two Apocynaceae species: Geissospermum laeve (Vell.) Miers and Alstonia balansae Guillaumin. As a first application, the MIADB-based annotation of an alkaloid extract of the barks of G. laeve led to the isolation and the structural elucidation of three new MIAs, two having a butyrolactone moiety. Afterwards, this approach was improved by the application of a new tool for in silico annotation called MetWork, which is based on metabolic prediction and on the generation of predicted tandem mass spectra. Following this approach, the exploration of the chemical space of an alkaloid extract of the leaves of A. balansae allowed the anticipation and further isolation of five novel MIAs of the N-oxide-sarpagine type. The stereochemistry of all the new molecules could be determined on the basis of experimental and predicted electronic circular dichroism spectra.In the introduction of this manuscript the multiple uses of molecular networking for the identification of small natural molecules are described, as well as the biosynthetic interconnections in the MIAs group. The creation and evolution of the MIADB are then presented, followed by its utilization in efficient dereplication workflows for the targeting of new natural products within complex mixtures from Apocynaceae species
Brosson, Sébastien. "Analyse protéomique de la voie endocytaire de Trypanosoma cruzi et Caractérisation de lectine de type C chez Trypanosoma cruzi et Trypanosoma brucei brucei". Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/217780.
Texto completo da fonteDoctorat en Sciences
info:eu-repo/semantics/nonPublished
Boireau-Adamezyk, Elise. "Spectroscopies vibrationnelles (MCR et ATR-FTIR) et Chromatographie Liquide couplée à la Spectrométrie de Masse Haute Résolution (LC-HR-MS) : Outils d’investigation in vivo de l’impact du vieillissement cutané sur le Stratum Corneum aux niveaux tissulaire, supra-moléculaire et moléculaire". Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112070/document.
Texto completo da fonteSkin is the external surface defining the human body in space. Its outer-most layer is a thin biological membrane, called Stratum Corneum(SC), that protects the internal organs from desiccation as well as chemical or mechanical external aggressions. The present thesis aimsin a first step, to summarize the current knowledge regarding the effects of intrinsic and extrinsic aging on SCphysiology,based on available literature. The experimental part addresses the gaps in our understanding of the effects of chronological aging and photoaging on the SC barrier function and hydration, using traditional methods (such as trans epidermal water loss and skin conductance) as well as more advanced ones (vibrational spectroscopies, liquid chromatography in normal phase tandem mass spectrometry high resolution with an APCI source and an Orbitrap detector. As these methods are non-invasive, all studies have been carried out in vivo. The evolution of the barrier function has been studied at the tissular, molecular and supramolecular levels using confocal Raman micro-spectroscopy and infrared spectroscopy. Then the link between the intrinsic aging and the ceramides of the intercorneocytary lipid matrix has been studied by liquid chromatography tandem mass spectrometry. The discriminant molecules between young and old population have been identified by a chemometric analysis. The evolution of cutaneous hydration at the tissular, molecular and supramolecular level has also been investigated. The variations in the NMF composition and the SC water content have been studied by Raman spectral descriptors. Moreover, the structural variations of water molecules impacting the supramolecular organization of the lipid structures have been evaluated. Chronological aging and chronic exposure to environmental factors mildly affect SC barrier function and hydration levels. However, the processes controlling these properties are affected by aging in a site-dependent fashion
Garenaux, Estelle. "Variabilité structurale des glycoconjugués : étude réalisée chez les Hyménoptères, les Oiseaux et les Protistes parasitaires". Lille 1, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-Garenaux.pdf.
Texto completo da fonteMoussaoui, Louardi. "Applications de la spectrométrie de masse type MALDI-TOF à la bactériologie et à la distinction de variants génétiques". Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00872251.
Texto completo da fonteLacroix, Marlène. "Optimisation d'une méthode de dosage de neurotransmetteurs par le couplage LC/Fluo/MS : études théoriques du marquage au NDA par spectrométrie de masse haute résolution, modélisation moléculaire et étude quantitative de relations structure-temps de rétention (3D-QSRR)". Toulouse 3, 2007. http://thesesups.ups-tlse.fr/47/.
Texto completo da fonteSome amino acids and peptides are neurotransmitters involved in neurological diseases. As they are very low concentration in biological samples, HPLC coupled with a fluorescence detector and a mass spectrometer is performed for the identification and the quantification of these molecules. As amino acids are not fluorescent natively, they are labelled with a fluorogenic dye: the naphthalene-2,3-dicarboxaldehyde (NDA) and a nucleophile (CN-). The labelling for the peptides (enkephalins) is slightly modified in order to facilitate the ionisation in positive mode in mass spectrometry: the nucleophile CN- is substituted by an aminothiol easily ionisable, the N,N-dimethylaminoethanethiol (MeAT). Some theoretical studies are investigated in molecular modelling, high resolution mass spectrometry and H/D exchange studies in order to explain the results obtained on each labelling
Marcoux, Julien. "Analyse structurale et fonctionnelle de la NADPH oxydase des neutrophiles : utilisation de la spectrométrie de masse pour caractériser les changements de conformations de p47(phox) lors de son activation". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENV010.
Texto completo da fonteNADPH oxidase (NOX) is a multienzymatic complex found in many cellular types, responsible for reactive oxygen species (ROS) production. The neutrophilic NOX is composed of two transmembrane proteins (gp91(phox) and p22(phox)) that make up the catalytic core and three cytosolic factors (p47(phox), p67(phox) and p40(phox)). Upon activation, p47(phox), undergoes conformational changes that this study attempts to define in order to better understand the regulation of this complex involved in many diseases. In neutrophils, ROS are responsible for phagocyted pathogen destruction. It therefore appears essential to better understand the molecular bases of the NOX activation mechanism to consider its future regulation. This study has identified a number of conformational changes on p47(phox) by limited proteolysis and Deuterium eXchange coupled to Mass Spectrometry (DXMS). The AIR release, providing better accessibility to the p22(phox) binding site was confirmed and characterized from both structural and functional points of view, on the entire protein. Furthermore, a novel surface controlling p47(phox) auto-inhibited state has been discovered. Site-directed mutagenesis within this surface confirmed this hypothesis by identifying two key residues (R162 and D166) responsible for this auto-inhibition and therefore possible future candidates for therapeutic targets. The relative binding properties of these mutants with GST-p22(phox)Cter and liposomes were investigated using Biacore™ and pull-down assays, respectively. The identification of these residues provided a better understanding of the p47(phox) activation mechanism, and in particular of how AIR unmasking leads to PX domain release. Finally, a methodological study showed that plasmespin 2 from Plasmdium falciârum was a new tool that may improve DXMS
Derappe, Christian. "Étude structurale d'oligosaccharides isolées d'urine humaine de gestation : mise en évidence de l'excrétion de glycosides inconnus phosphoryles ou dérivés du myo-inositol". Paris 6, 1986. http://www.theses.fr/1986PA066325.
Texto completo da fonteBlanc, Stéphanie. "Matériaux III-V épitaxies sur substrats GaAs(111) pour structures laser émettant au-delà du micromètre". Toulouse 3, 2002. http://www.theses.fr/2002TOU30170.
Texto completo da fonteTarisien, Mehdi. "Dynamique de la fragmentation de molécules simples induite par impact d'ion multichargé". Caen, 2003. https://tel.archives-ouvertes.fr/tel-00005217.
Texto completo da fonteRoux, Aurélie. "ANALYSE DU METABOLOME URINAIRE HUMAIN PAR CHROMATOGRAPHIE LIQUIDE COUPLEE A LA SPECTROMETRIE DE MASSE A HAUTE RESOLUTION". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2011. http://tel.archives-ouvertes.fr/tel-00641529.
Texto completo da fonteBelva, Hélène. "Les Spectres de masse en ionisation Electrospray de petites protéines basiques à multiples ponts disulfure reflètent-ils leur conformation ?" Rouen, 2000. http://www.theses.fr/2000ROUES072.
Texto completo da fonte