Immunomodulatory and neuroprotective effect of cryopreserved allogeneic mesenchymal stem cells on spinal cord injury in rats

This study aimed to evaluate the immunomodulatory and neuroprotective effects of allogeneic and cryopreserved mesenchymal stem cells (MSCs) on spinal cord injury. A total of 120 rats were distributed into the following groups: negative control (NC) - without injury, positive control (PC) - with injury without treatment, and group treated with MSC (GMSC) - with injury and treated. Motor function was evaluated by the BBB test at 24, 48, and 72 h and at 8 and 21 postoperative days. Spinal cords were evaluated by histopathology and immunohistochemistry to determine the expression of CD68, NeuN, and GFAP. IL-10, TNF-alpha, IL-1 beta, TGF-beta, BDNF, GDNF, and VEGF expression was quantified by RT-PCR. The GMSC presented higher scores for motor function at 72 h and 8 and 21 days after injury, lower expression of CD68 at 8 days, and lower expression of GFAP at 21 days compared to the PC. In addition, higher expression of NeuN and lower degeneration of the white matter occurred at 21 days. The GMSC also showed higher expression of IL-10 24 h after injury, GDNF at 48 h and 8 days, and VEGF at 21 days. Moreover, lower expression of TNF-alpha was observed at 8 and 21 days and TGF-beta at 24 h and 21 days. There were no differences in the expression of IL-1 beta and BDNF between the GMSC and PC. Thus, cryopreserved MSCs promote immunomodulatory and neuroprotective effects in rats with spinal cord injury by increasing IL-10, GDNF, and VEGF expression and reducing TNF-alpha and TGF-beta expression.Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG)CAPESVeterinary SchoolLaboratory of Molecular Biology of the Department of Immunology and Biochemistry of the Institute of Biological SciencesUniv Uberaba, Dept Med Ver, Uberaba, MG, BrazilUniv Fed Minas Gerais, Escola Med Vet, Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, MG, BrazilUniv Estadual Santa Cruz, Dept Ciencias Biol, Ilheus, BA, BrazilUniv Estadual Santa Cruz, Dept Ciencias Agr & Ambientais, Ilheus, BA, BrazilUniv Fed Sao Paulo, Dept Biociencias, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Biociencias, Santos, SP, BrazilWeb of Scienc

AC ignition of HID lamps –statistical and formative lag times

Noble gas discharges are typically used in lighting applications, under a very large range of conditions. A lot of modelling and experimental work has already been done in order to describe the starting behaviour of lamps. Focusing on high-pressure systems, high voltages needed for the ignition of lamps pose a problem. The purpose of this work is to examine the mechanisms of AC lamp ignition, which was already proven to be efficient in lowering HID lamp ignition voltage. More specifically, we use electrical measurements and observe the discharge by means of iCCD imaging to determine the lag times associated with AC lamp ignition. We use sine voltage with frequencies ranging from 60 kHz to 1 MHz, with various rise rates of the voltage amplitudes. Lamps we use are standard 70 W Philips burners, filled with 0.3 or 0.7 bar Argon or Xenon. We find that the statistical lag times in the system can be as long as 0.15 s and that they are at least two orders of magnitude longer than formative lag times

Psychological building blocks for dynamic road lighting: Understanding light's role in feelings of safety at night

Road lighting serves a host of functions at night, yet puts a substantial burden on our total energy consumption. Without exception, technical solutions to reduce the use of energy (e.g., new light sources, interactive road lighting) impact user perceptions and acceptance in ways that are not yet understood. In an experimental field study, conducted in our interactive road lighting testbed, we investigated pedestrians’ preferences for various static road lighting scenarios, in particular as they relate to feelings of safety, and the psychological mechanisms behind them. The testbed enabled us to manipulate the light, keeping other factors constant, thus offering experimental rigor and control. Following a paired-comparison paradigm, fifty female participants rated three light distributions on two street segments according to perceived safety. They then assessed each light distribution for each street segment on psychological and perceptual attributes. Research is ongoing; results will be reported at the conference

Support-Induced Effects of LaFeO3Perovskite on the Catalytic Performances of Supported Pt Catalysts in DeNOxApplications

International audienceA comparative investigation of the catalytic performance in the simultaneous conversion of NOx and N2O has been achieved on supported nanosized Pt particles interacting with conventional alumina and perovskite based materials. Particular attention has been paid to successive thermal treatments under reductive and oxidative atmospheres which induce bulk and surface reconstructions. Those modifications considerably alter the catalytic behavior of Pt in interaction with LaFeO3 or γ-Al2O3 in terms of activity and selectivity toward the selective transformation of NOx to nitrogen at low temperature. Changes in physicochemical properties have been examined using appropriate techniques, such as H2-temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) of CO adsorption. It has been found that oxidic Pt4+ species initially stabilized on LaFeO3 lead after subsequent H2 reduction to the formation of metallic nano-Pt particles in stronger interaction than on γ-Al2O3 support and then become more resistant to sintering during thermal aging in 1000 ppm NO, 1000 ppm N2O, 3 vol % O2, 0.5 vol % H2O, and 0.5 vol % H2 at 500 °C. Correlatively, significant improvements have been observed in the selective reduction of NOx to nitrogen. This study opens new prospects in the development of supported catalysts containing low Pt loadings because of the existence of stronger interactions with perovskite supports

Study of TiO2 anatase nano and microstructures with dominant {001} facets for NO oxidation

Introduction: TiO2 anatase nanoplates and hollow microspheres were fabricated by a solvothermal-hydrothermal method using titanium isopropoxide as a titanium precursor and hydrofluoric acid as a capping agent in order to enhance the formation of the {001} crystal facets of the anatase nanocrystals. Methods: These different morphological structures of TiO2 anatase can be achieved by only changing the solvent, keeping the amount of the precursor and of the capping agent identical during the solvothermal-hydrothermal process. Results and discussion: After calcination of the samples, the adsorbed fluoride atoms on the {001} crystal facets of the TiO2 anatase nanocrystals were completely removed from their surface according to XPS analysis. The calcined TiO2 anatase structures were higher crystallized and the specific surface area of the catalysts increased, enhancing their photocatalytic activity in comparison to the non-calcined TiO2 anatase structures. All TiO2 anatase samples with adsorbed as well as non-adsorbed fluoride atoms on their {001} crystal facets, exhibited a higher photonic efficiency than Degussa P25, which was used as a reference. Conclusion: The fluoride free TiO2 anatase nanoplates exhibited the best photocatalytic activity in oxidizing the NO gas to NO2 and NO3-. © 2012 Springer-Verlag