Mineralization of calcium phosphate crystals was examined on porous silicon (PSi) scaffolds with respect to the dependence of crystal formation on the average pore size of PSi. PSi multilayer wafers fabricated by electrochemical etching were moni- tored via their reflectivity spectra over time in a biologically relevant osteogenic solution. The evolution of the mean refractive index of the PSi scaffold is the signature of the in situ crystals nucleation within the pores. Crystals were then characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman micro-spectroscopy. The results in- dicate that the average pore size of PSi highly influences nucleation and crystal formation.

In this work, a combination of optical and electrochemical studies are performed in order to elaborate a suitable porous silicon (PSi) substrate for biosensing and biomaterial applications. We report on the electrochemical behavior of PSi multilayer stabilized by thermal oxidation, applying electrochemical impedance spectroscopy and cyclic voltammetry measurements. The strength of the method is evidenced when adsorption of small (12-mer) peptides is monitored. Our aim is to combine the advantages offered by the large sensing area of the PSi multilayers and the high sensitivity of the electrochemical technique for improved biosensing.

Heat and photochemical reactions with human hemoglobin and photosensitizer were monitored by holography interference method in gelatin phantom. The method has successfully facilitated monitoring the reactions as a high- resolution refraction index mapping in real time video regime. Methylene Blue was exploited as a photosensitizer. Keywords: Holographic Interferometry, imaging, photodynamic therapy, photochemical reactions

Spinal cord injuries (SCI) lead to major disabilities affecting > 2.5 million people worldwide. Major shortcomings in clinical translation result from multiple factors, including species differences, development of moderately predictive animal models, and differences in methodologies between preclinical and clinical studies. To overcome these obstacles, we first conducted a comparative neuroanatomical analysis of the spinal cord between mice, Microcebus murinus (a nonhuman primate), and humans. Next, we developed and characterized a new model of lateral spinal cord hemisection in M. murinus. Over a 3-month period after SCI, we carried out a detailed, longitudinal, behavioral follow-up associated with in vivo magnetic resonance imaging (1H-MRI) monitoring. Then, we compared lesion extension and tissue alteration using 3 methods: in vivo 1H-MRI, ex vivo 1H-MRI, and classical histology. The general organization and glial cell distribution/morphology in the spinal cord of M. murinus closely resembles that of humans. Animals assessed at different stages following lateral hemisection of the spinal cord presented specific motor deficits and spinal cord tissue alterations. We also found a close correlation between 1H-MRI signal and microglia reactivity and/or associated post-trauma phenomena. Spinal cord hemisection in M. murinus provides a reliable new nonhuman primate model that can be used to promote translational research on SCI and represents a novel and more affordable alternative to larger primates.