Search results for "cellules M"
showing 10 items of 11 documents
Involvement of Kv3.1 potassium chanels in 7-ketocholesterol, 24S-hydroxycholesterol and C24 : 0-induced lipotoxicity on 158N and BV-2 cells : relatio…
2017
Potassium (K+) is involved in the regulation of cellular excitability, cell cycle regulation, cell viability, neuroprotection and maintenance of microglial and oligodendrocytic functions. Potassium dysfunction, described in several neurodegenerative diseases such as Alzheimer's Disease (AD), multiple sclerosis (MS), Parkinson's disease and Huntington's disease, may be a potential therapeutic target. The underlying toxic mechanisms of these neurodegenerative pathologies involve oxysterols, which are oxidized cholesterol derivatives, and fatty acids including those associated with peroxisomal metabolism. 7-ketocholesterol (7KC), 24S-hydroxycholesterol (24S-OHC) and tetracosanoic acid (C24:0),…
Etude des effets cohérents dans la vapeur de rubidium atomique sous irradiation laser bi-chromatique
2013
The effect of electromagnetically induced transparency is observed, using nanocelland microcell. The EIT-resonance with good parameters (high contrast and small FWHM) is obtained in thick cells. The EIT-resonance splitting in magnetic field is observed for the cases of D1-line of 85Rb and 85Rb. The theoretical model, explaining the EIT-resonance components frequency shift dependence on magnetic field strength is presented. The theoretical and experimental results are compared and good agreement is shown. Also the EIT-resonance behavior in hyperfine Paschen-Back regime is presented and explained. For the first time the N-type resonance in microcell is observed. Good parameters of theN-type r…
Study of optical and magneto processes in Rb atomic vapor layer of nanometric thickness
2012
Using a narrow-band resonant fluorescence spectra from a nano-cell with a thickness of L= [lambda]/2, and VSOP resonances formed at a thickness L =[lambda] ([lambda] is the wavelength of the resonant radiation), for the first time it was experimentally investigated the behaviour of the frequency and intensity (transition probabilities) of the atomic hyperfine structure transitions between the 85Rb, 87Rb, D1 and D2 lines Zeeman sublevels in external magnetic fields in range 5 - 7000G. The behaviour of tens of previously unstudied atomic transitions was analyzed and it is demonstrated that the intensities of these lines can both greatly increase, and decrease (tenfold). For the first time it …
Study of the natural cactus extracts protective effects on oxidative stress and inflammation related to peroxisomal β-oxidation deficiencies
2023
The objective of my thesis work was to better understand the role of microglial cells in neuroinflammation initiated in several neurovegetative peroxisomal leukodystrophies and to explore the protective effects of substances from the cactus Opuntia ficus indica. To this end, we used as an in vitro model microglial cells deficient in ATP Binding Cassette D transporters (ABCD 1 and ABCD 2) or acyl-CoA oxidase 1 (ACOX1). These are two BV-2 murine cell lines, deficient in Abcd1/Abcd2-/- or deficient in Acox1-/-, obtained elsewhere by gene editing using the CRISPR/Cas9 methodology. Our results made it possible to: (i) characterize, by differential centrifugation and isopycnic ultracentrifugation…
Etude de l'influence de la leptine sur les mécanismes cellulaires de la mise en route du travail dans un modèle d'accouchement prématuré : approches …
2015
Maternal obesity is associated with a wide spectrum of adverse pregnancy outcomes leading to higher rates of postdate pregnancies or preterm deliveries. Finding new strategies for the management of the Threat of Preterm Labor (TPL) is an important Public Health issue. Indeed, the only available strategy (tocolytic drugs) inhibiting uterine contractions, does not allow delaying parturition for more than 48 hours. The physio-pathological mechanisms leading to TPL remain poorly understood, but it has been shown that labor onset is associated with a phenotypic switch of myometrial smooth muscle cell from a proliferative to a contractile phenotype. In this work, we investigated the effect of lep…
Mitophagy in myeloid cells : role in infection with gram-negative bacteria
2017
Sepsis and related organ dysfunctions remain a leading cause of mortality in intensive care units. Increasing evidences have shed light on an unexpected link between mitochondria and immune cell functions. Alterations in mitochondrial functions have been reported in peripheral blood cells in sepsis. We hypothesize here that mitophagy might impact on phagocyte functions in the context of bacterial infection. Mitophagy is a mitochondria-dedicated autophagy that governs the elimination of dysfunctional mitochondria. We demonstrated here in vivo and in vitro that macrophages exposed to Gram-negative bacteria or their cell wall component LPS display a marked inhibition of mitophagy that constitu…
Rôle de Tif1gamma dans les différenciations granulo-monocytaire et macrophagique
2015
Chronic myelomonocytic leukemia (CMML) is a hematologic stem cell disease whose characteristics correspond to myelodysplastic/myeloproliferative syndroms (MDS/MPS). Hematopoietic conditional deletion of Tif1γ in mice leads to the development of a MDS/MPS, mimiking human CMML, when age is comprised between 6 to 10 months, defining Tif1γ as a tumour suppressor gene. Moreover, peritoneal macrophage population in these mice is decreased despite a monocytosis.The aims of my work were first to characterize in sick mice the myeloid population, and second to study macrophage differentiation. The myeloid population in Tif1γΔ/Δ mice is morphologically immature, with granulocytic and monocytic feature…
Bleomycin induced pulmonary toxicity and its subpleural onset
2016
Idiopathic Pulmonary Fibrosis (PF) is a rare and devastating disease without efficient treatment at this time. Idiopathic FP is characterized by accumulation of myofibroblasts and has a typical sub-pleural onset suggesting a role of the pleura in the disease. Transforming Growth Factor (TGF)-ß1 induces transformation of pleural mesothelial cells (PMC) into active cells exhibiting myofibroblast phenotype. Heat shock proteins can act as regulator of the TGF-ß1 signaling. A role for caspase-1/IL-1ß axis has already been described in animal models of PF.The heat shock protein AlphaB-crystallin has been studied in PF at the PMC level and the importance of caspase-1/IL-1ß axis has been investigat…
Aspects fonctionnels et pronostiques des cellules myéloïdes suppressives et de Foxp3 dans le cancer
2011
Evasion of immune surveillance by certain tumour cells seems to be a basic requirement for tumour development in preclinical models and in humans. The mechanisms by which the tumour mediates its immune evasion are manifold, and involve the majority of immune system cells. Among these, immunoregulatory cells such as myeloid-derived suppressor cells (MDSCs) or regulatory T lymphocytes (T-regs, which express the transcription factor Foxp3) appear to play a predominant role. The results presented in this work aim to improve our understanding of the functional and prognostic roles of myeloid suppressor cells and T-regs in cancer, focussing particularly on how these cells are modulated by chemoth…