RGTA® or ReGeneraTing Agents mimic heparan sulfate in regenerative medicine: from concept to curing patients

The importance of extracellular matrix (ECM) integrity in maintaining normal tissue function is highlighted by numerous pathologies and situations of acute and chronic injury associated with dysregulation or destruction of ECM components. Heparan sulfate (HS) is a key component of the ECM, where it fulfils important functions associated with tissue homeostasis. Its degradation following tissue injury disrupts this delicate equilibrium and may impair the wound healing process. ReGeneraTing Agents (RGTA®s) are polysaccharides specifically designed to replace degraded HS in injured tissues. The unique properties of RGTA® (resistance to degradation, binding and protection of ECM structural and signaling proteins, like HS) permit the reconstruction of the ECM, restoring both structural and biochemical functions to this essential substrate, and facilitating the processes of tissue repair and regeneration. Here, we review 25 years of research surrounding this HS mimic, supporting the mode of action, pre-clinical studies and therapeutic efficacy of RGTA® in the clinic, and discuss the potential of RGTA® in new branches of regenerative medicine

Early Energy Deficit in Huntington Disease: Identification of a Plasma Biomarker Traceable during Disease Progression

Huntington disease (HD) is a fatal neurodegenerative disorder, with no effective treatment. The pathogenic mechanisms underlying HD have not been elucidated, but weight loss, associated with chorea and cognitive decline, is a characteristic feature of the disease that is accessible to investigation. We, therefore, performed a multiparametric study exploring body weight and the mechanisms of its loss in 32 presymptomatic carriers and HD patients in the early stages of the disease, compared to 21 controls. We combined this study with a multivariate statistical analysis of plasma components quantified by proton nuclear magnetic resonance (1H NMR) spectroscopy. We report evidence of an early hypermetabolic state in HD. Weight loss was observed in the HD group even in presymptomatic carriers, although their caloric intake was higher than that of controls. Inflammatory processes and primary hormonal dysfunction were excluded. 1H NMR spectroscopy on plasma did, however, distinguish HD patients at different stages of the disease and presymptomatic carriers from controls. This distinction was attributable to low levels of the branched chain amino acids (BCAA), valine, leucine and isoleucine. BCAA levels were correlated with weight loss and, importantly, with disease progression and abnormal triplet repeat expansion size in the HD1 gene. Levels of IGF1, which is regulated by BCAA, were also significantly lower in the HD group. Therefore, early weight loss in HD is associated with a systemic metabolic defect, and BCAA levels may be used as a biomarker, indicative of disease onset and early progression. The decreased plasma levels of BCAA may correspond to a critical need for Krebs cycle energy substrates in the brain that increased metabolism in the periphery is trying to provide

Mid-infrared characterization of refractive indices and propagation losses in GaSb/Al X Ga 1−X AsSb waveguides

International audienceWe report experimental results on M-lines characterization of GaSb refractive index as a function of doping level and lattice mismatch in the range of 2.15–7.35 μm with an accuracy of 10−3. We apply the same procedure to quaternary AlxGa1−xAsSb alloys lattice-matched to GaSb to study the refractive index evolution with aluminum fraction and with wavelength. We compare our measurements to theory, and we establish new parameter values for the dispersion law of GaSb. These parameters are confirmed by the excellent agreement between the calculated curves and experimental measurements performed on quaternary alloys. Using these values of optical indices, we design a GaSb/AlGaAsSb ridge waveguide and characterize the losses using the Fabry-Perot method at 2 μm. Very low losses are demonstrated in the range of 1 dB/cm and below in a single mode waveguide structure

DNA chip microstructured on silicon

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An architecture for genomics analysis in a clinical setting using Galaxy and Docker

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Activité protectrice d'un mimétique de l'héparane dans la mucite radio-induite chez la souris

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