We report here some pre-clinical testing of new scaffolds. To compare these second generation ceramic scaffolds more suitable for a tissue engineering approach we had to first establish animal models and analysis procedures including the use of X-ray-computed microtomography associated with X-rays synchroton radiation.

The stability and quality of regenerated bone and vessel network was assessed 3 years after grafting intervention, with conventional procedures and in‐line holotomography. The regenerated tissue from the graft sites was found to be composed of a fully compact bone with a higher matrix density than control human alveolar spongy bone from the same patient. Although the bone regenerated at the graft sites is not of the proper type found in the mandible, it creates steadier mandibles, may well increase implant stability, and, additionally, may improve resistance to mechanical, physical, chemical, and pharmacological agents.

No abstract

The surface of polyhydroxybutyrate (PHB) storage granules in bacteria is covered mainly by proteins referred to as phasins. The layer of phasins stabilizes the granules and prevents coalescence of separated granules in the cytoplasm and nonspecific binding of other proteins to the hydrophobic surfaces of the granules. Phasin PhaP1 Reu is the major surface protein of PHB granules in Ralstonia eutropha H16 and occurs along with three homologues (PhaP2, PhaP3, and PhaP4) that have the capacity to bind to PHB granules but are present at minor levels. All four phasins lack a highly conserved domain but share homologous hydrophobic regions. To identify the region of PhaP1 Reu which is responsible for the binding of the protein to the granules, N-terminal and C-terminal fusions of enhanced green fluorescent protein with PhaP1 Reu or various regions of PhaP1 Reu were generated by recombinant techniques. The fusions were localized in the cells of various recombinant strains by fluorescence microscopy, and their presence in different subcellular protein fractions was determined by immunodetection of blotted proteins. The fusions were also analyzed to determine their capacities to bind to isolated PHB granules in vitro. The results of these studies indicated that unlike the phasin of Rhodococcus ruber, there is no discrete binding motif; instead, several regions of PhaP1 Reu contribute to the binding of this protein to the surface of the granules. The conclusions are supported by the results of a small-angle X-ray scattering analysis of purified PhaP1 Reu , which revealed that PhaP1 Reu is a planar, triangular protein that occurs as trimer. This study provides new insights into the structure of the PHB granule surface, and the results should also have an impact on potential biotechnological applications of phasin fusion proteins and PHB granules in nanobiotechnology.