Matsuzaki S.,Estaing University Hospital Center |
Matsuzaki S.,Clermont University |
Matsuzaki S.,French National Center for Scientific Research
Human Reproduction | Year: 2014
study question: Is epigallocatechin-3-gallate (EGCG) treatment effective in the treatment of fibrosis in endometriosis? summary answer: EGCG appears to have antifibrotic properties in endometriosis. what is known already: Histologically, endometriosis is characterized by dense fibrous tissue surrounding the endometrial glands and stroma. However, only a few studies to date have evaluated candidate new therapies for endometriosis-associated fibrosis. study design, size, duration: For this laboratory study, samples from 55 patients (45 with and 10 without endometriosis) of reproductive age with normal menstrual cycles were analyzed.Atotal of 40 nude mice received single injection proliferative endometrial fragments from a total of 10 samples. participants/materials, setting,methods: The in vitro effects of EGC Gand N-acetyl-L-cysteine on fibrotic markers (alphasmooth muscle actin, type I collagen, connective tissue growth factor and fibronectin) with and without transforming growth factor (TGF)-b1 stimulation, as well as on cell proliferation, migration and invasion and collagen gel contraction of endometrial and endometriotic stromal cells were evaluated by real-time PCR, immunocytochemistry, cell proliferation assays, in vitro migration and invasion assays and/or collagen gel contraction assays. The in vitro effects of EGCG on mitogen-activated protein kinase (MAPK) and Smad signaling pathways in endometrial and endometriotic stromal cellswere evaluated bywestern blotting. Additionally, the effects ofEGCGtreatment on endometriotic implants were evaluated in a xenograft model of endometriosis in immunodeficient nude mice. mainresults andthe role of chance: Treatment with EGCG significantly inhibited cell proliferation, migration and invasion of endometrial and endometriotic stromal cells frompatients with endometriosis. In addition,EGCGtreatment significantly decreased the TGF-b1-dependent increase in the mRNA expression of fibrotic markers in both endometriotic and endometrial stromal cells. Both endometriotic and endometrial stromal cell-mediated contraction of collagen gels were significantly attenuated at 8, 12 and 24 h after treatment with EGCG. Epigallocatechin-3-gallate also significantly inhibited TGF-b1-stimulated activation of MAPK and Smad signaling pathways in endometrial and endometriotic stromal cells. Animal experiments showed that EGCG prevented the progression of fibrosis in endometriosis. limitations, reasons for caution: The attractiveness of epigallocatechin-3-gallate as a drug candidate has been diminished by its relatively low bioavailability. However, numerous alterations to the EGCG molecule have been patented, either to improve the integrity of the native compound or to generate a more stable yet similarly efficacious molecule. Therefore,EGCGand its derivatives, analogs and prodrugs could potentially be developed into agents for the future treatment and/or prevention of endometriosis. wider implications of thefindings: Epigallocatechin-3-gallate is a potential drug candidate for the treatment and/or prevention of endometriosis. © The Author 2014.
Peyretaillade E.,Clermont University
Heredity | Year: 2014
Fungal species play extremely important roles in ecosystems. Clustered at the base of the fungal kingdom are Microsporidia, a group of obligate intracellular eukaryotes infecting multiple animal lineages. Because of their large host spectrum and their implications in host population regulation, they influence food webs, and accordingly, ecosystem structure and function. Unfortunately, their ecological role is not well understood. Present also as highly resistant spores in the environment, their characterisation requires special attention. Different techniques based on direct isolation and/or molecular approaches can be considered to elucidate their role in the ecosystems, but integrating environmental and genomic data (for example, genome architecture, core genome, transcriptional and translational signals) is crucial to better understand the diversity and adaptive capacities of Microsporidia. Here, we review the current status of Microsporidia in trophic networks; the various genomics tools that could be used to ensure identification and evaluate diversity and abundance of these organisms; and how these tools could be used to explore the microsporidian life cycle in different environments. Our understanding of the evolution of these widespread parasites is currently impaired by limited sampling, and we have no doubt witnessed but a small subset of their diversity.Heredity advance online publication, 3 September 2014; doi:10.1038/hdy.2014.78.
Karmanov V.A.,RAS Lebedev Physical Institute |
Mathiot J.-F.,Clermont University |
Smirnov A.V.,RAS Lebedev Physical Institute
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012
We present a coherent and operational strategy to calculate in a nonperturbative way, physical observables in light-front dynamics. This strategy is based on the decomposition of the state vector of any compound system in Fock components, and on the covariant formulation of light-front dynamics, together with the so-called Fock sector dependent renormalization scheme. We apply our approach to the calculation of the electromagnetic form factors of a fermion in the Yukawa model, in the nontrivial three-body Fock space truncation, for rather large values of the coupling constant. We find that once the renormalization conditions are properly taken into account, the form factors do not depend-within our numerical accuracy-on the regularization scale when the latter is much larger than the physical masses. We then extend the Fock space by including antifermion degrees of freedom. © 2012 American Physical Society.
Pizarro D.,University of Alcala |
Bartoli A.,Clermont University
International Journal of Computer Vision | Year: 2012
This paper presents a method for detecting a textured deformed surface in an image. It uses (wide-baseline) point matches between a template and the input image. The main contribution of the paper is twofold. First, we propose a robust method based on local surface smoothness capable of discarding outliers from the set of point matches. Our method handles large proportions of outliers (beyond 70% with less than 15% of false positives) even when the surface self-occludes. Second, we propose a method to estimate a self-occlusion resistant warp from point matches. Our method allows us to realistically retexture the input image. A pixel-based (direct) registration approach is also proposed. Bootstrapped by our robust point-based method, it finely tunes the warp parameters using the value (intensity or color) of all the visible surface pixels. The proposed framework was tested with simulated and real data. Convincing results are shown for the detection and retexturing of deformed surfaces in challenging images. © 2011 Springer Science+Business Media, LLC.
Marchand S.,Clermont University
Ecological Economics | Year: 2012
This paper analyzes the impact of agricultural technical efficiency on the propensity of farmers to convert natural land into agricultural plots, i.e., to deforest, in the Brazilian Legal Amazon (BLA). A two-step econometric approach is adopted. A bootstrapped translog stochastic frontier that is a posteriori checked for functional consistency is used to assess technical efficiency and these estimates are put into a land-use model to assess the impact of productivity on deforestation. Analysis of agricultural census tract data suggests that technical efficiency has a U-shaped effect: both less and more efficient farms use more land for their agricultural activities and so have a positive effect on deforestation. However, the majority of farms in the BLA are on the ascendant slope, so that efficiency implies more deforestation in the BLA. The poor environmental valuation of the Brazilian forest, the uneven land distribution, and the problem of the de facto openly accessed forested and "unproductive" lands in the BLA could explain the U-shaped effect of technical efficiency on the conversion of forested land into agricultural land. © 2012 Elsevier B.V..