Дисертації з теми "Matrices biologiques"
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Thibert, Valérie. "Développement d'outils miniaturisés pour l'analyse de traces dans les matrices biologiques." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2011. http://pastel.archives-ouvertes.fr/pastel-00650138.
Повний текст джерелаChafai, Djalil. "Contributions à l'étude de modèles biologiques, d'inégalités fonctionnelles, et de matrices aléatoires." Habilitation à diriger des recherches, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00346998.
Повний текст джерела(1) Modèles biologiques et statistique : modèles compartimentaux, pharmacocinétique et pharmacodynamie de population, estimateurs pour problèmes inverses stochastiques, modèles non-linéaires à effets mixtes, modèles de mélanges, algorithmes de type EM et ICF, modèles graphiques de covariance, modélisation en cancérologie, processus ponctuels, particules, files d'attentes, renormalisation de processus markoviens inhomogènes et formules de Feynman-Kac
(2) Inégalités fonctionnelles : inégalités de type Sobolev, concentration de la mesure, isopérimétrie rôle de la convexité dans les inégalités entropiques, tensorisation, noyau de la chaleur, groupe d'Heisenberg et dynamiques hypoelliptiques, files d'attentes, mélanges de lois
(3) Matrices aléatoires : spectre des matrices markoviennes aléatoires, graphes à poids aléatoires, théorèmes de type Wigner, Marchenko-Pastur, et Girko-Bai, convergence des valeurs propres extrémales, déformations de rang un.
Le concept le plus récurrent ici est celui de dynamique markovienne. Dans la première partie, ce sont les modèles à compartiments de la pharmacologie qui sont liés à de telles dynamiques. La seconde partie traite d'inégalités fonctionnelles associées à la vitesse et à la géométrie de dynamiques markoviennes. Enfin, la troisième partie traite de dynamiques markoviennes aléatoires. Ces trois parties ne se réduisent pas à l'étude de facettes de problèmes markoviens. Leur contenu balaye un spectre à la fois théorique et appliqué, et met en oeuvre des techniques et des concepts variés issus de l'analyse, des probabilités, et de la statistique.
Hassen, Imed Eddine. "Analyse de traces et ultratraces (organiques et inorganiques) dans les matrices biologiques." Lyon 1, 2004. http://www.theses.fr/2004LYO10126.
Повний текст джерелаBichon, Emmanuelle. "Challenge de l’analyse de dangers chimiques à l’état d’ultra-traces en matrices biologiques complexes." Thesis, Nantes, Ecole nationale vétérinaire, 2016. http://www.theses.fr/2016ONIR089F/document.
Повний текст джерелаThe study of the link between Human exposure tochemical substances (notably via his food the intake) and Health, is a major concern in our society and poses many challenges. We endeavoured to address one of them by producing reliable analytical data on foodstuffs and human biological fluids contamination. The development of analytical methods based on breakthrough technologies, capable of challenging theemerging (e.g. brominated flame retardants) or historical compounds measurement but through the prism of sensitivity and high throughput (e.g. steroids,organochlorine pesticides, dioxins andpolychlorobiphenyls), was at the heart of our work.Using a GC/APCI/MS with a triple quadripole systememerged as a favorable choice as our evaluations progressed. The association of gas chromatography and atmospheric pressure chemical ionisation brought in a remarkable gain in terms of selectivity, compared to the approaches traditionally selected in this field, andauthorized ultra-trace exploration in complex biologicalmatrices. This geometry allowed us to innovate by performing fast separations on an ultra-short 2.5 mcolumn. Besides, the mass analyser scan speed and high sensitivity gave us access to a reliable and multiparameters quantitative analysis. This work opens up excellent perspectives for the production of expanded external and internal exposure data to meet the future challenges surrounding Human exposome characterisation
Kontrimavičiūtė, Violeta. "Quantification de l'Ibogaïne et de la Noribogaïne dans différentes matrices biologiques : Étude pharmacocinétique chez l'homme." Montpellier 1, 2007. http://www.theses.fr/2007MON13503.
Повний текст джерелаGillery, Philippe. "Cultures de fibrolastes en matrices tridimensionnelles de collagene et de fibrine : etudes biologiques et metaboliques." Reims, 1989. http://www.theses.fr/1989REIMS005.
Повний текст джерелаCassoulet, Raphaël. "Développement et validation de méthode d'analyse multirésiduelle de contaminants organiques et inorganiques dans des matrices biologiques." Mémoire, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/11508.
Повний текст джерелаBertrand, Isabelle. "Détection et génotypage des kystes de Giardia lamblia à partir de matrices environnementales et d'échantillons biologiques." Nancy 1, 2005. http://docnum.univ-lorraine.fr/public/SCD_T_2005_0210_BERTRAND.pdf.
Повний текст джерелаJeudy, Jérémy. "Quantification de biomarqueurs protéiques dans des matrices biologiques complexes par spectrométrie de masse : développements et applications." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10242/document.
Повний текст джерелаOver the past decade, interest in the use of biomarkers in clinical studies has greatly increased. Quantification of a candidate protein biomarker in complex samples (eg. plasma) requires targeted and multiplexed assays. Immunoassays are the gold standard for their quantification. However, with the need for targeted and multiplexed methods, recent developments in mass spectrometry (MS) make a viable alternative to ELISA. The present work has addressed the problems encountered in this type of proteomic studies, and solutions that can be explored to improve the workflow of candidate biomarker’s evaluation. Methionine peptides are generally avoided due to their susceptibility to oxidation. However, it seemed interesting to study how their endogenous modifications could affect biological processes. In a first time, apolipoproteins were dismissed as a potential biomarker of Alzheimer’s disease due to oxidation impact. In the same time, problems associated with biological sample collection and storage were highlighted. DBS (Dried Blood Spot) and Vivid device evaluation from a panel of 32 blood proteins has provided a first possible solution to overcome these troubles. Thereafter, a new peptide quantification method called MRM3 was used to overcome biological matrix complexity. Reliable level determinations of 2 plasma proteins (C-Reactive protein and TIMP-1) and 2 urinary proteins (aquaporin-2 and podocin) were obtained. To improve sensitivity and reduce analysis solvent costs, performances of a micro chromatography platform were compared to a narrow-bore platform. This study highlighted the significant impact of the matrix effect on the analytical process, requiring new strategie development. Finally, to reduce sample complexity, evaluation of wide pore solid-phase extraction cartridges has been achieved. A protocol was successfully developed to analyze enzymes contained in commercial laundry samples. Finally to optimize biological sample preparation time, heated-assisted digestion and online desalting step were successfully associated. Only few hours were then required for quantitative analysis
Bertrand, Isabelle Schwartzbrod Janine. "Détection et génotypage des kystes de Giardia lamblia à partir de matrices environnementales et d'échantillons biologiques." [s.l.] ([s.n.]), 2005. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2005_0210_BERTRAND.pdf.
Повний текст джерелаHUTEAU, BERTRAND, and M. F. BONNORD. "Identification et dosage de traces d'organohalogenes par des methodes separatives et spectrometrie de masse. Application aux matrices biologiques." Paris 6, 1991. http://www.theses.fr/1991PA066164.
Повний текст джерелаRichard, Damien. "Gamma Hydroxy Butyrate : analyse par CPG/SM dans différentes matrices biologiques et interprétation pharmaco-toxicologiques d'études pré-cliniques et cliniques." Clermont-Ferrand 1, 2010. http://www.theses.fr/2010CLF1MM01.
Повний текст джерелаThis work presents development and validation of an original chromatography method of the GHB and its precursors (GABA, 1. 4 BD and GBL) in various biological matrices, by gas chromatography coupled with mass spectrometry detector. A study of stability of the blood samples shows variations of in vivo and in vitro concentrations of endogenous GHB. Then, a clinical protocol seeks the incorporation of the GHB in hair matrix after therapeutic administration of γOH®, to estimate the capacity of this biological matrix to detect an exogenous administration of GHB in particular during a chemical submission (such as drug sexual assault). Finally, an experimental protocol, made at the same time on human and animal samples, allows quantifying the GHB and its precursors and presents the various kinetics of post-mortem increase, to establish a correlation between concentrations and the post-mortem interval (PMI). This work shows at first that only conservation of biological samples in -20°C allows guaranteeing the validity of the biological results. In spite of an administration of important doses of γOH®, no variation of concentrations of GHB was able to be observed on the different segmental analyses of hair. Finally, a synthesis post-mortem of the GHB allows correlating the concentrations to the PMI but she cannot be still considered as a reliable biochemical marker in forensic science
Beaufils, Sylvie. "Synthèse électrochimique et caractérisation de nanoparticules d'hydroxypatite, mise en charge de matrices extracellulaires d'hydrogel et leurs caractérisations mécaniques et biologiques." Thesis, Reims, 2018. http://www.theses.fr/2018REIMS031/document.
Повний текст джерелаIn order to reduce morbidity and hospital stay, regenerative medicine is nowadays moving towards the development of less invasive surgical techniques. This search for a minimally invasive surgery has motivated the development of injectable matrices for bone tissue engineering. These matrices must also be able to harden in situ once injected, acquire the desired shape and mechanical properties compatible with the host tissue it intends to repair. Many hydrogels are already used for this application but none fully meets the required properties. The objective of this thesis is to develop new bone graft substitutes: hydrogels based on biopolymers associated with bone cells to achieve half synthetic and half biological grafts. Nanoparticles of calcium phosphates are added to improve the biological and mechanical properties of hydrogels. Hydroxyapatite, calcium phosphate chosen, has attracted much attention because of its chemical and structural similarity to the mineral constituent of human bone. The aim of this work is to synthesize firstly hydroxyapatite nanowires by the template method and secondly size controlled hydroxyapatite nanopowders by out-of-phase pulsed sonoelectrochemistry. Thirdly to improve the intrinsic properties of these three-dimensional structures, those nanoparticles of calcium phosphates will be added in the matrices of hydrogel synthesized by the LIOAD. Measurements of diffusion coefficient will be followed by testing cytotoxicity and biocompatibility of those materials. A subcutaneous study and bone model study will follow
Kiss, Agneta Kristina. "Mise en place d'outils analytiques et chimiométriques pour les études métabonomiques de matrices biologiques complexes par Spectrométrie de Masse Haute-Résolution." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10125.
Повний текст джерелаMy research work highlights the development of a metabonomic strategy through two topical issues: the doping in sport (Part A) and the Exposome (Part B). The first part includes two studies and aims to assess the contribution of metabonomics to the development of new screening tools. During these studies, I focused on the non-targeted analysis of clean and doped urine samples provided by the French Anti-Doping Agency and by volunteers. The originality of this approach lies in its non-targeted nature and, particularly, in its ability to highlight metabolic disruptions by (i) high-resolution (ToF) and very high-resolution (FT ICR) mass spectrometry and (ii) the analysis of multivariate data. The implemented strategy revealed several potential biomarkers for the use of tetrahydrocannabinol, budesonide and salbutamol. The second part of this thesis aims to evaluate the impact of vinclozolin on the hormonal system of rats and thus meets the requirements of the new regulations. For this study, I focused on testes extracts coming from rats treated with vinclozolin. Due to its comprehensive nature, the metabonomic study provided additional information to the previous targeted approach. All these results highlight the contributions and the limitations of metabonomics with regard to: (1) the choice and the preparation of biological samples, (2) the advantages and disadvantages of different analytical techniques, (3) the opportunities in terms of data processing, (4) the statistical requirements and (5) the biological value of the results
Lemaire, Rémi. "Nouveaux développements pour l'imagerie par spectrométrie de masse MALDI : applications aux problèmes biologiques et à la recherche de biomarqueurs dans le cancer de l'ovaire." Paris 6, 2006. http://www.theses.fr/2006PA066288.
Повний текст джерелаAraujo, Arthur Luiz Alves de. "Conception et réalisation d'un biocapteur à matrice d’électrodes pour la caractérisation de milieux biologiques par spectroscopie d’impédance." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0005.
Повний текст джерелаKnowledge of the electromagnetic properties of cells can provide early signals of disease or abnormal conditions in the human body for medical applications. In combination with microfluidic devices, impedance spectroscopy can be a powerful tool for sorting, analyzing, counting and discriminating cells. The main objective of this thesis is the characterization of isolated biological cells by measurement of unit-scale impedance spectroscopy and thus to be able to characterize them, in this thesis project we have done. The design and development of a coplanar electrode matrix biosensor are the second objective of this work, the idea being ultimately to be able to perform simultaneous measurements on several unit cells. The electrode matrix-shaped structure makes it possible to increase the number of cells measured as the number of electrodes increases. However, the electrode lead tracks can reduce the normalized impedance variation and thereby increase the difficulty in measuring cells between the electrodes. To analyze the effects of the connection tracks, propose improvements and observe the feasibility, we first used a simple 2x2 matrix. With this structure, we analyze analytically, by simulations and by experimental measurements, the influence of the connection tracks on the frequency band and on the standardized impedance variation. To reduce the effects of connection tracks, we have reduced their dimensions as well and we have used shown the advantage of using an insulator layer on the connection tracks
Fourier, Anthony. "Vers un marqueur biochimique des dégénérescences lobaires fronto-temporales : variations quantitatives et profils protéiques de la protéine TDP43 dans différentes matrices biologiques." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1269/document.
Повний текст джерелаFrontotemporal lobar degeneration (FTLD) syndrome is the second most common of presenile dementia. FTLD is a clinically heterogeneous syndrome and comprises many hereditary cases. Common neuropathological features rely on a degeneration of the frontal and/or anterior temporal lobes, associated to specific inclusions of aggregated proteins including TAR DNA binding protein 43 (TDP43). Unfortunately, no practical protein marker is currently validated to improve FTLD diagnosis in living patients.A cohort of FTLD patients with definite TDP43 pathology was defined with the development of specific genetic testing. An analysis of TDP43 concentrations in cerebrospinal fluid (CSF) was performed in this cohort and then compared to other cohorts well-characterized on clinical and neuropathological features. Finally, qualitative patterns of TDP43 were studied in compartments accessible from the patient’s living: profiles of soluble TDP43 protein (in CSF or in plasma) and intracellular TDP43 protein (in the formed elements of blood) were compared to protein patterns observed in brain tissues with TDP43 protein inclusions. Platelet samples exhibit similar characteristics to brain tissue and could become a candidate biomarker for FTLD probabilistic diagnosis
Stricot, Marlène. "Bioréacteurs à membranes à configuration externe : influence de la configuration du procédé sur la structuration des matrices biologiques et le colmatage des membranes." Toulouse, INSA, 2008. http://eprint.insa-toulouse.fr/archive/00000222/.
Повний текст джерелаThis study describes and analyses the impact of two side-stream membrane bioreactors on (1) the structure and the morphology of the biological aggregates, (2) fouling mechanisms and (3) global performances of the two processes. Two side-stream membrane bioreactors which generate very different shear stresses were compared. The first one was operated in an inside/out crossflow filtration mode with a high liquid velocity (5 m. S-1). The second reactor was working in an outside/in hollow fibre filtration mode with a low liquid velocity (< 0,1 m. S-1). Firstly, the effect of the configuration, in terms of filtration mode and hydrodynamics, on the sludge properties has been characterised for the two reactors. The investigation of the structuration mechanisms and supernatant quality reveals clear differences as well on bioflocs morphology/structure as on supernatant composition (COD, proteins, polysaccharides). The role of soluble /colloidal organics and more specifically of proteins and polysaccharides on (a) fouling ability of the sludge and (b) in situ short term fouling was underlined. The effect of toxic compounds on biological activity and membrane fouling was specifically characterised. At least, global performances of the two bioreactors in long term operation time were studied. The water treatment efficiency, in terms of organics and toxics removal, as well as sludge production of the two processes, was compared
Mentré, Pascale. "Localisation des cations par precipitation en microscopie electronique, reexaminee a la lumiere des acquisitions recentes sur l'etat de l'eau dans les matrices biologiques." Paris 6, 1991. http://www.theses.fr/1991PA066577.
Повний текст джерелаBéraud, Eric. "Etude des effets génotoxiques et de l'induction des phytochélatines chez Vicia faba (Fabaceae) exposée au cadmium : application du test Vicia micronoyaux à des matrices complexes." Metz, 2007. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2007/Beraud.Eric.SMZ0700.pdf.
Повний текст джерелаHigher plants demonstrate defence mechanisms whereby they are able to respond to both nutrient deficiencies and toxicants. In this work, cadmium genotoxicity and quantitative relationshps between different hierarchical endpoints in Vicia faba (broad bean) cultivated in both contaminated environment (i. E. Hydroponical and soils) were studied. Increases of miaonucleus (MN) frequencies (genotoxicity endpoint), phytochelatins induction and antioxidative enzyme activities (i. E. Superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, catalase, glutahone reductase) and manodialdehyde (MDA), indicator of lipid peroxidation, were analysed. To study the process of stress 1 adaptation in Vicia faba plants, different realistic CdCl2, concentrations were employed. F In hydroponic culture, the increase of micronucleus frequency was the first cadmium i , exposure effect that appeared (LOEC: 7,5 10-8 M CdCl2). Then decreases of antioxidative enzymes activities were observed (APX, SOD, CAT at 10-'M; MDA for 10-5M). Phytochelatins induction was detected from IO-~Mb, ut it was more effective from 10-'M. A tirne-concentration dependent response of cadmium was observed, for these cadmium exposure indicators. A tissue dependent response of cadmium was observed for enzymes activities and phytochelatins induction too. The micronuclei bioassay was also tested with V. Faba plants directly exposed in cadmium polluted soils and on leachates from multi contaminated soils. Our results suggest that the synthesis of phytochelatins, observed in higher degrees of stress, was related to the inactivation of other tolerance mechanisms and that it was associated with the metabolic cost of these mechanisms. The results also show that V. Faba micronuclei bioassay would be efficient for in situ studies of contaminated soils
Phuong, Ngoc Nam. "Développements analytiques pour la caractérisation et la quantification de la contamination en microplastiques de matrices sédimentaires et biologiques : application aux zones conchylicoles des Pays de la Loire." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4017/document.
Повний текст джерелаThe contamination by microplastics (particle inferior of 5 mm) was evaluated in all environmental compartments around the world with widely varying concentrations. This variability is due to spatial and temporal differences in contamination but also results from the lack of standardization of sampling, sample preparation and analysis methods. In this context, this thesis aimed to develop and validate fast analytical procedures of characterization and quantification of microplastics for sedimentary and biological matrices. The application of the validated protocols allowed to characterize the microplastic contamination of two bivalve species (the blue mussel Mytilus edulis and the pacific oyster Crassostrea gigas), wild and cultivated, and the sediments from three mudflats of the Atlantic coast (Pen-Bé, Coupelasse and Aiguillon Bay), at two seasons. The mean contamination was evaluated at 0.61 ± 0.56 and 2.1 ± 1.7 microplastic per mussel (N=120) and per oyster (N=60) respectively. In sediments, a mean of 67 ± 76 microplastic per kg dry weight (N=60) was measured. A large proportion of polyethylene and polypropylene fragments were observed in both matrices with a notable difference in the size range of detected microplastic: <100 μm for bivalves and between 100 and 250 μm for sediments. No significant effect of site, season or lifestyle for bivalves has been highlighted on microplastic contamination. In parallel, the sorption of six organic contaminants of marine waters has been studied on model microplastics made of polyethylene and polypropylene
Chapuis, Florence. "Immunoadsorbants et polymères à empreintes moléculaires pour l'extraction sélective de composés de matrices environnementales et biologiques : synthèse et caractérisation en vue de leur intégration au système total d'analyse." Paris 6, 2004. http://www.theses.fr/2004PA066049.
Повний текст джерелаCruz, Thomas. "Applications de la métabolomique par RMN du proton à l'étude de différentes matrices biologiques dans le cadre du mélanome, du glioblastome, de la maladie d'Alzheimer et de l'hypophosphatasie." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30098/document.
Повний текст джерелаMetabolomics consists in the general analysis of the metabolome of a biological system which is achieved by the use of one or more analytical techniques combined with chemometric tools. It allows an overall measurement of the metabolic response through the characterization and quantification of metabolites in a given sample. Herein, proton NMR was chosen as the analytical technique. This work allowed us to apply metabolomic study to four diseases. Our research focused on a specific aspect of each disease. A wide range of samples has been studied here, from cell lines to human samples through biopsies mouse brain. The first chapter is dedicated to the study of melanoma and deals with a human melanoma cell line in which the HIF-1a protein was restrained. Melanoma tumors of xenograft mice were studied with and without vemurafenib treatment. Thanks to these results, we were able to start a preliminary study concerning the tumors of human patients. These three studies show melanoma disorders within the bioenergetic metabolism. The second part of this work is related to the metabolomic study of Alzheimer's disease. Cerebrospinal fluids of healthy and diseased patients were compared to highlight any metabolic modification. In the third part, we present the first metabolomic study of a rare disease: hypophosphatasia. Furthermore, unlike the previous work concerning this disease, we chose to use murine model to detect any metabolic modification within mice brain. In the last part, a study of glioblastoma was performed to show metabolic differences due to changes in IRE1 protein in a glioblastoma cell line
Bamogo, William. "Capteurs chimiques à base de matrices nanoporeuses pour la détection de métabolites volatils de la tuberculose." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112010/document.
Повний текст джерелаTuberculosis kills nearly 2 million people each year, mainly because of late or inefficient diagnostic or late cures. The most efficient methods are often too expensive and too complex to implement in developing countries, areas of greater incidence of the disease. The aim of this project is the design of luminescent sensors for the detection of a very specific tuberculosis metabolite, nicotinic acid, detected in concentration ranging from around ten to hundred ppq, present in sick people’s breath, and to discriminate it from other metabolites.A terbium nitrate complex is used as its luminescence can be sensitized by organic ligands, as nicotinic acid. A first step was the optimization of the pH of aqueous solution to enhance the complexation between Tb3+ ion and nicotinic acid. A solution buffered at pH 6,4 using hexamine allows optimization of the complex formation and energy transfer from nicotinic acid to terbium. Sampling of nicotinic acid can be done in the range 400 nM-100 μM, or from 7,2 to 1,8 ppm.The second step was to design nanoporous matrices from silicon alcoxydes to obtain matrix with an intraporous pH of 6,4. We studied the changes of the matrix intraporous pH while trapping water vapor or carbon dioxide, present in high concentration in breath, using bromothymol blue as pH indicator. The matrices were produced from 2 silicon precursors, one of them containing an aminopropyle carbon chain, conferring an alkaline nature. Changes of the matrix pH between 6,5 and 6 were observed following the exposure of a silica matrix containing 3 % of the aminated precursor to water vapor to saturation. This range of pH value is optimized to favor Tb3+-nicotinic acid complex formation.In the last step, silica matrix containing 3% of the aminated precursor, doped with terbium and buffered at pH 6,4 with hexamine were designed. Luminescence measurements made on matrix exposed to vapors from pure nicotinic acid or saturated aqueous solution, showed an increase of the matrix luminescence, proof of the trapping of nicotinic acid in the nanoporous matrix and of the complexation between nicotinic acid and Tb3+. Trapping of nicotinic acid and subsequent complexation with Tb3+ are lowered by the presence of water vapor, which can partially deactivate the luminescent excited state of Tb3+. Interference studies showed that secondary metabolites as methyl nicotinate can only affect the luminescence of Tb3+/AN complex by competitive absorption of the excitation radiation. Detection methods free of interferences from the secondary metabolites are studied
Lesueur, Teddy. "Développement d’un nouveau bio-essai survie croissance copépodes "BASIC" : application et validation sur différentes matrices environnementales." Thesis, Le Havre, 2014. http://www.theses.fr/2014LEHA0019/document.
Повний текст джерелаSeine estuary is one of the most polluted in the northern hemisphere largely due to its urban and agricultural activities of its watershed. Despite this the copepod E. affinis represents 90% of zooplankton biomass in the Seine estuary. The aim of the thesis was to develop a new bioassay Survival Growth copepod with the copepod E. affinis on various environmental matrices. Initially, the bioassay was developed using sediments spiked with molecules representative models of estuarine contamination (APs, PAHS and PCBs) before being validated on natural sediments of the Seine estuary. The bioassay was applied in solution 4-NP and PCB 126 and Vibrio anguillarum from the Seine estuary. A multi-generational exposure protocol was applied under the same conditions for three generations. The results showed an effect on larval development after 6 days of exposure to sediments. In solution, similar results were obtained, including, retarded growth after two days of exposure to 4-NP and PCB 126 correlated with chitobiase activity levels. However, at the end of the experiment the result is not observed. At exposition with Vibrio anguillarum, increased activity was recorded chitobiase the first days, involving an increase in growth in the sixth day. As part of the multi-generational experimenting, the copepod appears to be stabilizing at the third generation
McSheehy, Shona. "Identification des espèces organiques d'arsenic et de sélénium dans les matrices biologiques par chromatographie en phase liquide couplée à la spectrométrie de masse. : ICP MS et électrospray MS/MS." Pau, 2001. http://www.theses.fr/2001PAUU3032.
Повний текст джерелаBousoumah, Radia. "Le challenge de l’analyse multi-résidus de perturbateurs endocriniens à activité estrogénique dans les fluides et tissus biologiques humains : Choix de stratégies de préparation des échantillons et de mesure par spectrométrie de masse." Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0028.
Повний текст джерелаFor over twenty years, the issue of endocrine disruptors (EDs) mobilizes the scientific community and public authorities because of the negative effects, actual or suspected, of these compounds on human health. In particular, the generation of internal exposure data (impregnation) in some subpopulations, which are recognized or assumed as being sensitive (pregnant women, fetuses, infants), is both a priority and a demanding field associated with a certain rarity. Considering their structural diversity and with regards to their physicochemical properties, the simultaneous analysis of a large panel of EDs remains a real analytical challenge. In this context, the objective of this work was to develop a multi-residue method for the simultaneous isolation and measurement of estrogenic endocrine disruptors (13 EDs in total). Firstly, an analysis method using liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) after chemical derivatisation by dansyl chloride was developed. Secondly, a molecularly imprinted polymer (MIP with phenolic imprint) was implemented for the simultaneous extraction of the targeted EDs from aqueous medium and biological matrices of increasing complexity (urine, serum, breast milk). The strategy developed on MIP was applied, after validation, to a set of samples (maternal serum, cord serum and urine of newborns). Finally, a column support grafted with estrogen receptor α (ERα column) was applied for the simultaneous isolation of the targeted compounds from an aqueous medium
Pirog, Antoine. "An embedded system for the multiparametric analysis of biological signals : application to the pancreatic biosensor of insulin demand." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0836/document.
Повний текст джерелаExtracellular recording of electrical activity is a widespread technique in neurosciences, but only recently has it been applied to pancreatic islets and beta cells. The ease of use of Microelectrode Arrays (MEAs) has opened new perspectives for the electrophysiology of pancreatic cells, including screening methods for clinics and biosensor approaches for the artificial pancreas. This thesis is a contribution to the design and characterization of a hybrid biosensor composed of pancreatic cells cultured on an MEA and dedicated processing electronics. This device is the product of multi-disciplinary projects conducted at IMS (Bioelectronics group), partnered with CBMN (Cell biology and Biosensors team), both at the University of Bordeaux. Projects also involved the endocrinology service of university hospitals in Bordeaux, Montpellier, Grenoble, and Geneva.The covered projects include:- ISLET-CHIP (French ANR 2013-PRTS-0017), investigating a method of evaluating the quality of a preparation prior to its transplantation in type-I diabetic patients.- BIODIA (EU FEDER), characterizing islet electrical response to glucose, hormone, and drug stimuli for screening, cell differentiation, and closed-loop approaches.- DIAGLYC (French regional grant 2017 1R30 226), investigating the use of the hybrid biosensor as an artificial pancreas front-end sensor.The thesis tackles the biosensor in both its electronic and biological aspects, its integration in applicative experimental setups, and experimental results. It also addresses the modeling of a closed regulation loop for type-I diabetic patients.First, the electronic processing platform is described. It is a custom board performing multichannel acquisition and digital signal processing. It is built around an FPGA (Field Programmable Gate Array) that makes its processing architecture versatile and evolutive. It is capable of measuring, displaying and storing multichannel data. Computation was optimized for low-processing latencies compatible with closed-loop configurations. Both its processing algorithms and architecture are detailed.Then, experimental results using this system and its algorithms are shown to illustrate islet response to glucose, drug, and hormone stimuli. Islet activity is quantified by analyzing Action Potentials (APs), and more importantly Slow Potentials (SPs), a novel electrical signature exclusively measured on pancreatic islets. These measurements in both steady state and dynamic regime help characterize the biosensor response, but also shed light on the endogenous algorithms of islets of Langerhans.Finally, approaches for integrating the biosensor in an artificial pancreas are investigated. The measured glucose and hormone responses are modeled and simulated in a full-body glucose-insulin system. This concept is novel in that the sensor in charge of measuring insulin demand in the body is not only sensitive to glucose, but also to blood hormones
Mériaux, Céline. "Imagerie du système nerveux central par spectrométrie de masse MALDI." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10059/document.
Повний текст джерелаIn 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
Planchenault, Thierry. "Activité protéolytique potentielle de la fibronectine : caractérisation et rôle biologique." Paris 12, 1998. http://www.theses.fr/1998PA120002.
Повний текст джерелаAbdallah, Maya. "Développer des hydrogels et étudier les effets des propriétés mécaniques sur les activités biologiques des podocytes." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS065.
Повний текст джерелаExtracellular matrix (ECM), non-cellular component, regulates and maintains the main biological activities of cells such as cellular survival, proliferation and differentiation. Recently, hydrogels scaffolds have shown a remarkable advancement as candidates for tissue engineering and regenerative medicine. Hydrogels are defined as hydrophilic polymer network having the ability to hold a large amount of water and biological fluid. Various natural and synthetic hydrogels have been studied and developed in many tissue regeneration purposes. They provide an appropriate mechanical support, chemical and biological cues mimicking the native extracellular matrix (ECM). These artificial matrices characteristics contribute to induce the cellular functions as adhesion, proliferation and differentiation. The thesis aim was to develop polymers based hydrogels and to study the effect of their physical properties on podocyte kidney cells. Synthetic hydrolyzed polyacrylamide based hydrogel (PAAm) was the choice of study where the physical properties can be tailored and tuned over a wide range. These scaffolds have provided elasticity similar to the in vivo glomerular basement membrane (GBM) and have shown a suitable candidate for the regulation of podocyte functions. Moreover, the development of synthetic and biologic hybrid hydrogels was able to mimic the biological and mechanical properties of native ECM. The combination of gelatin methacrylate and acrylamide (GelMA-AAm) based hydrogels have been investigated and has shown tunable mechanical properties mimicking the native kidney GBM elasticity and a significant attachment of podocytes without any surface functionalization with adhesion proteins. This work permits to investigate the cellular physiology and to develop kidney-on-chip in order to study the functions of kidney on both healthy and diseased states
Gilbert, Amélie. "Sélection et développement d'un réseau de refuges biologiques dans une matrice forestière intensivement aménagée." Thèse, [Rimouski, Québec] : Université du Québec à Rimouski, 2007.
Знайти повний текст джерелаTitre de l'écran-titre (visionné le 15 janvier 2008). Mémoire présenté à l'Université du Québec à Rimouski comme exigence partielle du programme de maîtrise en gestion de la faune et de ses habitats. Comprend un résumé. CaQRU CaQRU CaQRU Bibliogr.: f. 29-35. Webographie f. 35. Publié aussi en version papier. CaQRU
Luc, Guillaume. "Ingénierie tissulaire : Mise en oeuvre d’un procédé de fabrication d’une matrice oesophagienne biologique." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0423/document.
Повний текст джерелаDecellularized matrixes (DM) are commonly used to facilitate a constructive remodeling response in several types of tissue, including the esophagus. Surgical procedure of the esophagus is often complicated by stricture, but preclinical studies have shown that the use of a DM can mitigate stricture and promote a constructive outcome. Recognizing the potential benefits of DM derived from homologous tissue (i.e., site-specific ECM), the objective of the present study was to prepare, characterize, and assess the in-vivo remodeling properties of DM from porcine esophagus. The developed protocol for esophageal DM preparation is compliant with previously established criteria of decellularization and results in a scaffold that maintains important biologic components and an ultrastructure consistent with a good mechanical behavior. Stem cells remained viable when seeded upon the esophageal DM in vitro, and the in-vivo host response showed a pattern of constructive remodeling when implanted in soft tissue
Bourven, Isabelle. "Caractérisation de la fraction organique et minérale de la matrice extracellulaire issue de boues biologiques." Limoges, 2012. https://aurore.unilim.fr/theses/nxfile/default/bc875cd9-74ff-4bee-b5a5-2f0c156d5865/blobholder:0/2012LIMO4034.pdf.
Повний текст джерелаBioreactors allow making a wastewater biological treatment with biological sludge. Sludges are aggregates formed with microorganisms embbeded in an extracellular matrix (ECM). ECM which contains an organic and mineral fraction, is considered as the "house" of the biofilm. The study of ECM requires its extraction from sludge. We analyzed the impact of the extraction method on the PEC (extracellular polymers) from various biological sludge by steric exclusion chromatography (HPSEC) coupled with an UV detection. The impact of the extraction method on the mineral fraction of ECM from activated sludges was showed too. The scanning electronic microscopy showed the presence of a solid mineral fraction. We then characterized the protein fraction and the humic-like substances of the PEC by HPSEC coupled with fluorimetry. This method decides between proteins-like (wide range of molecular mass (MM)) and substances humiques-like (MM< 6kDa). We characterized specifically the protein fraction of the PEC with electrophoresis (SDS-PAGE) coupled with various stains. The PAS stain (periodic acid and Schiff reagent) allowed to show the presence of glycoproteins (MM : 100kDa). For the PEC from anaerobic granular sludge, the alcian blue staining at pH 2. 5 and pH 1 showed the presence of proteoglycan and sulphated proeoglycane respectively. The presence of these heteroprotein was confirmed by an immunodetection test on the glucidic motives (using lectins)
Boedec, Arthur. "Traitement d'effluents polysiloxaniques dans des matrices aqueuses salines : potentiel de la nanofiltration et de l'oxydation biologique." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30040/document.
Повний текст джерелаIndustrial production of silicones generates liquid streams containing siloxanes with high salinity. In a perspective of sustainable development and to consider the growing concern about the environmental impact of industrial residues, we are looking for treatment processes to remove siloxanes in wastewater. This study aims to evaluate the performance of two processes for the treatment of effluents containing siloxanes: nanofiltration and biological oxidation, Frontal nanofiltration experiments were carried out. Firstly, experiments with synthetic solutions (mix of water and siloxanes) have shown almost total siloxane retention in all conditions investigated. Then, experiments were performed with effluents of different compositions representative of industrial ones in order to evaluate the process robustness. It was concluded that nanofiltration is efficient to reduce the total organic content of the effluent and significantly reduces siloxanes concentration. Dilution of the effluent causes a decrease in TOC reduction and siloxanes retention, but the permeate quality is improved. Increasing salinity reduces the filtrate quality. Micro and ultrafiltration of identical effluents confirmed that only NF can reach a high level of siloxane retention. Tangential nanofiltration experiences were performed in order to prepare a more complete study which is necessary to anticipate industrialization of the process. Siloxanes biodegradability was explored by Oxitop method. No biological activity induced by siloxanes was recorded in Oxitop tests with activated sludge from wastewater treatment plant, but no toxic or inhibitory effects were observed. A pilot membrane bioreactor was fed in the laboratory for 6 months with a solution containing siloxanes to try to acclimate activated sludge to siloxane. Oxitop tests performed with sludge taken from the pilot did not show acclimation of microorganisms to siloxanes
Bechaux, Julia. "Identification de peptides à activité biologique issus de matrices carnées porcines ayant subi un traitement enzymatique." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC043.
Повний текст джерелаThe poorly valorized animal biomass from the pig sector requires the implementation of new recovery processes. The identification of bioactive peptides (BPs) is a promising way to valorize this biomass. From an environmental point of view, it is possible to reduce the consumption of natural resources (surface of culture, water, energy) having used for the feeding of the pigs, by providing an economically interesting outlet to these by-products. On the other hand, the generation of bioactive peptides that can be used in the fields of pharmacology, cosmetics or food is part of the growing consumer demand for the development of more natural molecules. The objective of this project is to identify optimal hydrolysis conditions allowing generating, from porcine by-products, new bioactive molecules for nutritional or medical purposes. An in silico potency study is conducted on four porcine products (heart, liver, lung and muscle) to evaluate their ability to generate PBs, based on the use of different enzymes. In addition, the stability of the generated peptides is evaluated in the gastrointestinal tract using an in vitro static model. Finally, the method for the generation of BPs is developed at a pilot scale. In silico studies allowed to select the papain / subtilisin pair of enzymes for the generation of the highest number of peptides with antioxidant, antidiabetic (DPP4i) and antihypertensive (ACEi) activities. In vitro validation confirmed the presence of antioxidant and DPP4i activities in the four hydrolysates generated with papain and subtilisin. The biological activity of heart, liver and lung hydrolysates increases during gastrointestinal digestion. Experiments on the digestion of a pork patty supplemented with heart hydrolysate have shown that i) the cooking temperature (70°C or 90°C) slightly modulates iDPP4 and antioxidant activities during digestion, ii) supplementation significantly increases iDPP4 activity compared to a control sample. A moderate effect of this supplementation on the antioxidant activity was observed and iii) the antioxidant activity of the supplemented pork patty increases significantly (+ 40%) between the gastric and intestinal compartment. In addition, the methodology for the generation of bioactive peptides is possible on a pilot scale with commercial enzymes and adapted hydrolysis parameters. Peptide fractions with significant bioactivity can be valued as aromatic ingredients and to supplement a food product for obtaining health claims
Martelet, Armelle. "Détection et identification de bactéries dans des matrices complexes par amplification phagique et spectrométrie de masse." Paris 6, 2013. http://www.theses.fr/2013PA066577.
Повний текст джерелаMONZAT, VERONIQUE. "Regulation de l'expression d'elements de la matrice extracellulaire dans des cellules transfectees par le fgf-2." Paris 7, 1995. http://www.theses.fr/1995PA077233.
Повний текст джерелаBesse, Marie. "Caractérisation des interactions des nanoparticules de dyoxyde de titane avec les interfaces biologiques." Compiègne, 2012. http://www.theses.fr/2012COMP2039.
Повний текст джерелаNanoparticles (NPs) have unique properties due to their small size (less than 100 nm). Titanium dioxide NPs (TiO2 NPs) are widely used by the industrial sector for the manufacture of products such as sunscreens, paints, chocolates and air filters. Nowadays, it is known that Human are daily exposed to TiO2 NPs but their impact on health and potential toxicity mechanisms still unclear. Therefore, we studied the TiO2 NPs interaction with the biological interfaces and their components, i. E. Proteins and lipids. Biological membranes were studied using model membranes mimicking the lipid composition of the pulmonary surfactant and the cell membrane. Our results showed that TiO2 NPs deeply disturb the lipid distribution and increase the membrane order which lead to a modification of the physical state of the membrane. This could seriously disturb the membrane dynamic and function. Our work on TiO2 NPs interaction with proteins adsorbed on a surface revealed that proteins from the extracellular matrix (ECM) catch a lot more TiO2 NPs than serum proteins. Then, cell experiments showed that the presence of TiO2 NPs on a fibronectine layer (a major ECM protein) inhibits the adhesion of preosteoblastic cells. The adhesion step is required for various cell processes such as differentiation and proliferation. These conclusions are very important to consider since TiO2 NPs could be released from titanium bone implants into the surrounding tissue
Doillon, Charles. "Etudes des interactions entre les cellules et des molécules de la matrice extracellulaire pour une application aux biomatériaux biologiques." Lyon 1, 1993. http://www.theses.fr/1993LYO10156.
Повний текст джерелаFloquet, Nicolas. "Etudes structurales de peptides d'élastine et de collagene : structure, assemblage, propriétés mécaniques et biologiques de la matrice extracellulaire." Paris 7, 2004. http://www.theses.fr/2004PA077072.
Повний текст джерелаDombre-Hérard, Anne-Laure. "Reparation de lesions de l'epithelium respiratoire : migration cellulaire et interactions cellules-matrice extracellulaire (doctorat : genie biologique)." Reims, 1997. http://www.theses.fr/1997REIMM204.
Повний текст джерелаLE, BOULAIRE STEPHANIE. "Surveillance des residus de produits veterinaires dans la viande. Methodes d'analyse multi-residus par dispersion de la matrice en phase solide (mspd)." Nantes, 1996. http://www.theses.fr/1996NANT2056.
Повний текст джерелаCurtil, Alain. "Contribution au développement d'un nouveau type de substitut valvulaire biologique : recolonisation de matrices porcines lyophilisées par des cellules humaines autologues." Lyon 1, 1997. http://www.theses.fr/1997LYO1T309.
Повний текст джерелаMagnan, Laure. "Développement, par ingénierie tissulaire, d’un substitut vasculaire entièrement biologique et humain grâce à l’utilisation d’une approche textile." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0284.
Повний текст джерелаWhen autologous blood vessels are not available for bypass surgery, synthetic grafts are used but display high failure rates. Indeed, despite their good mechanical properties, their synthetic surface lead to thrombosis and intimal hyperplasia, which cause poor long-term patency in many applications. Using tissue engineering, completely biological and human vascular grafts have been produced by rolling sheets of extracellular matrix synthesized by dermal human fibroblasts in vitro. Using a new assembly technique based on a textile approach, grafts were produced three-time faster. To do so, sheets were cut into yarns to construct vascular substitute by weaving. This manuscript includes three articles. The first one aimed at showing the rich composition of the matrix, describing the organization of its complex network of collagens and demonstrating that the devitalization by drying the matrix did not significantly affect this organization. The second one described the mechanical properties of the yarns depending on the twisting, matrix age or different treatments useful for the manufacturing process. It also demonstrated some of the assembly techniques possible with this human yarn, as well as its possible use as a suture or to build a vascular graft. The third article showed the survival of the yarns subcutaneously implanted for 6 month in nude rats. The implants created little inflammatory response, were mildly remodeled and kept a significant mechanical strength. Decellularization did not show results improvement compared to the simple devitalization, demonstrating that the remaining cellular fragments were not a meaningful activator of the innate immune system. To conclude, this thesis is the first demonstration of the production of human textiles, without using any exogenous material and that are mechanically very strong. Both the devitalization and the textile approach have allowed to create a simpler allogeneic model, faster and cheaper but with an intact potential of integration in vivo, that will be studied very soon with a long-term implantation of the textile in the bloodstream
Legrand, Claire. "Implication de la mmp-9 et du systeme upa/plasmine dans la migration des cellules epitheliales bronchiques humaines (doctorat : genie biologique)." Reims, 2000. http://www.theses.fr/2000REIMM210.
Повний текст джерелаMercier, Isabelle. "Rôle de la matrice extracellulaire dans l'arrangement du cytosquelette des fibroblastes humains." Lyon 1, 1996. http://www.theses.fr/1996LYO10165.
Повний текст джерелаIraqi, wafae. "Validation de biomarqueurs du remodelage de la matrice extracellulaire chez des patients ayant une insuffisance cardiaque : Données des études EPHESUS et CARE-HF." Thesis, Nancy 1, 2009. http://www.theses.fr/2009NAN10083/document.
Повний текст джерелаBackground—Left ventricular (LV) remodeling is one of the determinants of heart failure (HF).Circulating biomarkers of collagen turnover provide a useful tool for the assessment of cardiac extracellular matrix (ECM) remodeling. This process has not been investigated in patients with congestive HF and LV systolic dysfunction after acute myocardial infarction (AMI) neither the influence of cardiac resynchronisation therapy (CRT) on such biomarkers was. The aim of this work was to evaluate collagen circulating biomarkers as assessment tools of ECM remodeling, in relation with cardiovascular prognosis: • In patients from the Eplerenone Post–Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS). This trial evaluated the effects of the selective aldosterone receptor antagonist eplerenone versus placebo in decreasing all cause deaths rate, cardiovascular mortality or cardiovascular hospitalisations, in patients with HF after AMI complicated by LVSD and treated by standard pharmacologic therapy including angiotensin converting-enzyme inhibitors, beta-blockers and diuretics. and • In patients with moderate to severe HF with LV dysfunction and cardiac dyssynchrony, already receiving standard pharmacologic therapy including angiotensin converting-enzyme inhibitors, beta-blockers and diuretics. Patients were randomly assigned to treatment with pharmacological therapy alone or with the addition of CRT in the Cardiac Resynchronization in Heart Failure (CARE-HF) trial. Methods? Serum levels of collagen biomarkers: synthesis biomarkers PIIINP and PINP, degradation marker type I collagen telopeptide (ICTP) and metalloproteinase (MMP) inhibitors (TIMP-1), were measured in 476 patients from the EPHESUS study at baseline, 6 and 9 months. Serial measurements of serum levels of PIIINP, PINP, ICTP and MMP-1 were measured in 260 patients enrolled in the CARE-HF trial at baseline, 3 and 18 months. Results? In the EPHESUS study the combination of ICTP and brain natriuretic peptide (BNP) levels above median at baseline was associated with all-cause mortality and the composite end point of cardiovascular death or heart failure hospitalization. During follow-up, levels of PINP and PIIINP were found to be consistently lower in the eplerenone group and significantly lower after 6 months. In the CARE-HF study, baseline serum concentrations of PIIINP were strongly associated with long-term mortality independently from NT-ProBNP. Serum PIIINP concentrations were similar in patients assigned to CRT or control during follow-up. Neither NT-ProBNP nor any of the tested collagen biomarkers predicted the response to CRT. Conclusion : Changes in biomarkers of collagen synthesis and degradation suggest that extracellular matrix remodeling is an active process in patients in the acute phase of HF after AMI. Eplerenone suppresses post–acute myocardial infarction collagen turnover changes and acts through ECM remodeling. Collagen biomarkers are associated with cardiovascular outcomes in acute and chronic HF settings. Fibrosis degree, as assessed by collagen biomarker circulating levels is not associated with dyssynchrony degree and with beneficial effects of CRT, which is recommended in HF patients with dyssynchrony
Brauge, Thomas. "Étude des exopolysaccharides de la matrice extracellulaire des biofilms de Listeria monocytogenes." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10151/document.
Повний текст джерелаThe aim of this work was to study the role of exopolysaccharides in the formation of Listeria monocytogenes biofilm and their resistance to cleaning procedure in industry. We showed that the major exopolysaccharide present in the extracellular matrix of L. monocytogenes biofilm was teichoic acid, which was identical at the structure to the parietal teichoic acid. We identified that 50% of 93 strains of 1/2a serotype studied had a mutation in the lmo2550 gene that could lead to non-branching of the teichoic acid with the N-Acetylglucosamine residue (GlcNAc). We therefore examined mutants of EGD-e reference strain which had inactivated lmo2549 or lmo2550 or lmo2537 or tagO1tagO2 genes allowing highlighting the absence of the GlcNAc residue on teichoic acids. The mutation of these genes had changed the L. monocytogenes surface properties, decreased the adhesion to stainless steel and modified the architecture of 48h-biofilms. Furthermore, they were more susceptible to a circuit cleaning procedure with an important detachment, a change in the architecture of the biofilm and the presence of non-cultivable but viable cells and dead cells after passage of the caustic soda flow versus the wild-type EGD-e strain. The aim of this work was to better understand the role of the extracellular matrix in the formation of L. monocytogenes biofilm and then find the procedure to eradicate it in the industrial environment
Loïc, Martin. "Analyse et interprétations expérimentales en polarimétrie de Mueller. Applications biomédicales." Phd thesis, Université de Bretagne occidentale - Brest, 2011. http://tel.archives-ouvertes.fr/tel-00664642.
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