Behavior tests and immunohistochemical retinal response analyses in RCS rats with subretinal implantation of Okayama-University-type retinal prosthesis

We have developed a photoelectric dye-coupled polyethylene film as a prototype of retinal prosthesis, which we named Okayama University-type retinal prosthesis. The purposes of this study are to conduct behavior tests to assess vision in Royal College of Surgeons (RCS) rats that underwent subretinal implantation of the dye-coupled film and to reveal retinal response to the dye-coupled film by immunohistochemistry. Polyethylene films were made of polyethylene powder at refined purity, and photoelectric dyes were coupled to the film surface at higher density compared with the prototype. Either dye-coupled film or dye-uncoupled plain film used as a control was implanted subretinally from a scleral incision in both eyes of an RCS rat at 6 weeks of the age. Behavior tests 2, 4, 6, and 8 weeks after implantation were conducted by observing head turning or body turning in the direction consistent with clockwise or counterclockwise rotation of a black-and-white-striped drum around a transparent cage housed with the rat. After the behavior tests at 8 weeks, rats' eyes were enucleated to confirm subretinal implantation of the films and processed for immunohistochemistry. In the behavior tests, the number of head turnings consistent with the direction of the drum rotation was significantly larger in RCS rats with dye-coupled- compared with plain-film implantation [P < 0.05, repeated-measure analysis of variance (ANOVA), n = 7]. The number of apoptotic neurons was significantly smaller in eyes with dye-coupled- compared with plain-film implantation (P < 0.05, Mann-Whitney U test, n = 6). In conclusion, subretinal implantation of photoelectric dye-coupled films restored vision in RCS rats and prevented the remaining retinal neurons from apoptosis

Processing of nanostructured polymers and advanced polymeric based nanocomposites

The control of the nanostructure and the addition of nanoparticles to polymers have led to structural and functional property enhancements in a number of polymeric systems as a material answer to continuous requirements from advanced industrial sectors. The availability of new nanoparticles with extraordinary properties (i.e. carbon nanotubes, graphenes, but also nanoclays, nanocellulose, metals and ceramics) have determined new and exciting possibilities for a continuous enlargement of polymer markets. However, the potentialities of these new materials are still strongly dependent on the development and scaling-up of reliable processing routes. Therefore, the purpose of this report is to review the main processing approaches for nanostructured polymers and nanocomposites starting with a brief review of available nanoparticles and on their functionalization to promote a better polymer-particle interaction. Regarding processing, the review firstly addresses the bottom-up approaches typically adopted for nanostructured polymers, blends and copolymers. Then, the different technologies required by the top-down processing of thermoplastic and thermosetting polymer matrix systems are reviewed. Finally, the report addresses the recent applications of nanostructured polymers and nanocomposites as matrices of advanced composite materials. In all cases, the main processing approaches and the main structural and functional properties characterizing these materials and their potential and current industrial applications are specifically addressed.We are indebted to the Spanish Ministry of Economy and Competitiveness (MINECO) for their economic support of this research (MAT2013-48059-C2-1-R). LP acknowledges the support of a JAEDoc grant from CSIC cofinanced by FSE. JMK acknowledges the support of the Russian Ministry of Education and Science within State Contract No. 14.Z50.31.0002.Peer Reviewe