The Variable Influence of Orthotic Management on Hip and Pelvic Rotation in Children with Unilateral Neurogenic Equinus Deformity

BACKGROUND Equinus deformity with or without concomitant drop foot is a common finding in children with unilateral spastic cerebral palsy and spastic hemiplegia of other causes. Hypothetically, these deformities may lead to pelvic retraction and hip internal rotation during gait. Orthoses are used to reduce pes equinus during gait and to restore hindfoot first contact. OBJECTIVE We aimed to investigate whether the use of orthotic equinus correction reduces rotational hip and pelvic asymmetries. METHODS In a retrospective study, 34 children with unilateral spastic cerebral palsy or spastic hemiplegia of other causes underwent standardized instrumented 3D gait analysis with and without orthotic equinus management. We analyzed the differences in the torsional profile during barefoot walking and while wearing orthoses, as well as investigated the influence of ankle dorsiflexion and femoral anteversion on pelvic and hip kinematics and hip kinetics. RESULTS Wearing orthoses corrected pes equinus and pelvic internal rotation at the end of the stance phase and in the swing phase compared to barefoot walking. Hip rotation and the rotational moment did not significantly change with orthoses. Orthotic management or femoral anteversion did not correlate to pelvic and hip asymmetry. CONCLUSION The findings indicate that the correction of the equinus by using orthoses had a variable effect on the asymmetry of the hip and pelvis and internal rotation; both appear to have a multifactorial cause that is not primarily driven by the equinus component

Fusion-dependent formation of lipid nanoparticles containing macromolecular payloads

The success of Onpattro™ (patisiran) clearly demonstrates the utility of lipid nanoparticle (LNP) systems for enabling gene therapies. These systems are composed of ionizable cationic lipids, phospholipid, cholesterol, and polyethylene glycol (PEG)-lipids, and are produced through rapid-mixing of an ethanolic-lipid solution with an acidic aqueous solution followed by dialysis into neutralizing buffer. A detailed understanding of the mechanism of LNP formation is crucial to improving LNP design. Here we use cryogenic transmission electron microscopy and fluorescence techniques to further demonstrate that LNP are formed through the fusion of precursor, pH-sensitive liposomes into large electron-dense core structures as the pH is neutralized. Next, we show that the fusion process is limited by the accumulation of PEG-lipid on the emerging particle. Finally, we show that the fusion-dependent mechanism of formation also applies to LNP containing macromolecular payloads including mRNA, DNA vectors, and gold nanoparticles

Delivery of non-viral naked DNA vectors to liver in small weaned pigs by hydrodynamic retrograde intrabiliary injection

Hepatic gene therapy by delivering non-integrating therapeutic vectors in newborns remains challenging due to the risk of dilution and loss of efficacy in the growing liver. Previously we reported on hepatocyte transfection in piglets by intraportal injection of naked DNA vectors. Here, we established delivery of naked DNA vectors to target periportal hepatocytes in weaned pigs by hydrodynamic retrograde intrabiliary injection (HRII). The surgical procedure involved laparotomy and transient isolation of the liver. For vector delivery, a catheter was placed within the common bile duct by enterotomy. Under optimal conditions, no histological abnormalities were observed in liver tissue upon pressurized injections. The transfection of hepatocytes in all tested liver samples was observed with vectors expressing luciferase from a liver-specific promoter. However, vector copy number and luciferase expression were low compared to hydrodynamic intraportal injection. A 10-fold higher number of vector genomes and luciferase expression was observed in pigs using a non-integrating naked DNA vector with the potential for replication. In summary, the HRII application was less efficient (i.e., lower luciferase activity and vector copy numbers) than the intraportal delivery method but was significantly less distressful for the piglets and has the potential for injection (or re-injection) of vector DNA by endoscopic retrograde cholangiopancreatography

CORIA Aeronautical Combustion Facilities and Associated Optical Diagnostics

International audienceThe scientific activities presented in this article are within the field of the design of new concepts of combustion chambers and the exploration of their benefits to increase the combustion and environmental efficiencies of advanced air-breathing propulsion systems. These scientific activities are performed in the "Complexe de Recherche Interprofessionnel en Aérothermochimie" (CORIA) research laboratory, a joint research institute organized between the CNRS, the University of Rouen and the INSA-Rouen Engineering School. CORIA contributes through its recognized expertise in numerical simulation, optical diagnostic measurements and experiments in large-scale combustors to improving the understanding of multi-scale multi-physics physical mechanisms governing the lean combustion of future combustion chambers. In this context, the " Centre de Combustion Avancée pour l'Aéronautique du Futur " (C-CAAF) recently created at CORIA is aimed at providing:• An instrumentation and optical diagnostic platform gathering various laser/opti-cal diagnostic techniques (PIV, LDV for the characterization of the aerodynamic field, PDPA, GRT for the characterization of the distribution of fuel droplets, CARS for measuring the thermal field and main species concentration, OH-PLIF and Schlieren for analyzing the flame structure, LII, NO-PLIF, CO-PLIF for measuring pollutants in the flame, etc.). These laser/optical diagnostic techniques are used to provide unique laboratory tools to perform time-resolved, simultaneous, multidimensional measurements of scalar parameters governing turbulent and multi-phase combustion. Furthermore, these diagnostic tools can be combined to obtain detailed correlations on these scalar parameters.• Multiple setups , from academic burners to complex combustors operating at high pressures. Through the perfect control of their operating conditions, academic burners are designed to assist in the development and validation of innovative optical diagnostic tools. They also provide a precise determination of the relevant chemical and physical parameters, enabling conclusions to be drawn about the underlying partly-coupled combustion processes. Technical combustion chambers are developed to provide a high-fidelity experimental database, in order to improve the innovative architectures of ultra-low NOx aeronautical injectors operating with real multi-component liquid fuels (kerosene, alternative fuels, biofuels, etc.), to identify the interaction mechanisms between several fuel injection systems and to validate the predictive capability of gas turbine combustion models

Rotational and Vibrational Temperature and Density Measurements by Planar Laser Induced NO-Fluorescence Spectroscopy in a Nonequilibrium High Enthalpy Flow

LIF experiments were performed in the flow field of the high enthalpy facility L2K. This arc heated facility, which is mainly used for testing thermal protection materials, offers a wide choice of flow conditions to simulate the stagnation conditions during shuttle re-entry. The flow conditions are dominated by nonequilibrium effects. For the operation conditions of L2K translational and rotational temperatures are assumed to be in equilibrium, but large differences between rotational, vibrational and electronic temperatures occur. Laser induced fluorescence is used to determine rotational and vibrational temperatures and the density of NO in the free stream and behind a bow shock upstream of a blunt body. The flow is modelled numerically using a quasi 1D-code. Good agreement is achieved between the experimental and numerical data in the free stream. The data are also compared with the CARS measurements performed at the same flow conditions in the same facility. Differences in the free stream vibrational temperature of N2 and NO are due to the faster vibrational relaxation of NO-molecules

Coherent Anti-Stokes Raman Scattering Measurements and Computational Modeling of Nonequilibrium Flow

An experimental study is conducted in a high-enthalpy continuous facility to investigate the nonequilibrium shock-layer airflow induced by a two-dimensional body. The rotational and vibrational temperatures of nitrogen as well as the number density are measured by recording the rovibrational spectra of molecular nitrogen using coherent anti-Stokes Raman scattering spectroscopy. Measurements are performed in the freestream and within the shock layer induced by a disk model. Difficulties specific to the application of an optical technique to a high enthalpy flow are discussed, and flows parameters are given. The nozzle and shock-layer flows are modeled numerically using a nonequilibrium Navier-Stokes solver. Good agreement is achieved between the experimental and calculated results

Imagerie quantitative de fluorescence induite par laser : methode et applications

Communication to : ASTELAB 2001 - 6eme salon international des laboratoires d'essai, Paris (France), 13-15 mars 2001SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.2001 n.52 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Imagerie de fluorescence induite par laser de OH et thermometrie DRASC dans une couche de melange supersonique reactive

Communication to : 37eme colloque d'aerodynamique appliquee 'Aerodynamique et propulsion des vehicules a grande vitesse', Arcachon (France), 28-30 mars 2001SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.2001 n.63 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc