The microalga Volvox carteri as a cell supportive building block for tissue engineering

Background: V. carteri f. nagariensis constitutes, in its most simplified form, a cellularized spheroid built around and stabilised by a form of primitive extracellular matrix (ECM). Methods: We developed a modular approach to soft tissue engineering, by compact stacking V. carteri-based building blocks. This approach is made possible by the structure and cell adhesive properties of these building blocks, which results from the composition of their algal ECM. Results: A primary biocompatibility assessment demonstrated the cytocompatibility of the algal suspension, its histogenesis-promoting properties, and that it did not induce an inflammatory response in vitro. These results allowed us to consider the use of this algal suspension for soft tissue augmentation, and to initiate an in vivo biocompatibility study. V. carteri exhibited cellular fate-directing properties, causing (i) fibroblasts to take on an alkaline phosphatase+ stem-cell-like phenotype and (ii) both human adipose-derived stem cells and mouse embryonic stem cells to differentiate into preadipocytes to adipocytes. The ability of V. carteri to support histogenesis and adipogenesis was also observed in vivo by subcutaneous tissue augmentation of athymic mice, highlighting the potential of V. carteri to support or influence tissue regeneration. Conclusions: We present for the first time V. carteri as an innovative and inspiring biomaterial for tissue engineering and soft tissue regeneration. Its strategies in terms of shape, structure and composition can be central in the design of a new generation of bio-inspired heterogeneous biomaterials recapitulating more appropriately the complexity of body tissues when guiding their regeneration

16S rDNA analysis of bacterial communities associated with the hyper accumulator Arabidopsis halleri grown on a Zn and Cd polluted soil

International audienceHaving a glimpse of the relationships between the zinc and cadmium hyper accumulator Arabidopsis halleri and its rhizospheric bacteria may represent an interesting step towards the implementation of a rhizoremediation strategy based on this plant. Until now, these relationships remained unraveled. This work aimed to give some insights into the composition of the bacterial communities surrounding A. halleri when it grows on a soil harboring elevated amounts of zinc and cadmium, as well as into the influence that plant roots may exert on them. Industrial highly polluted soils containing different amounts of zinc and cadmium and surrounding A. halleri plants were sampled and their bacterial contents were harvested at various distances from A. halleri root system. Genetic diversity was assessed through DNA extraction, PCR amplification, 16S rDNA libraries construction, RFLP analysis and partial sequencing. Nine mini-libraries of hundred clones each were established and analyzed. Up to 481 independent clones were sequenced and identified at genus level. Twelve genera among 48 were found particularly well represented in the different sub-fractions analyzed. At class level, ten different classes were identified. Alpha-proteobacteria, Gamma-proteobacteria, Flavobacteria and Sphingobacteria were the main contributors to flora diversity. In the less polluted soil, roots proximity seems to affect negatively Alpha-proteobacteria and Flavobacteria and positively Gamma-proteobacteria. A rhizospheric selection limited to some specific genera was also observed when pollution raised

cDNA sequence of Aldgh, the mouse homolog of the X-linked adrenoleukodystrophy gene

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A New Human Gene (DXS1357E) with Ubiquitous Expression, Located in Xq28 Adjacent to the Adrenoleukodystrophy Gene

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Identification of mutations in the putative ATP-binding domain of the adrenoleukodystrophy gene.

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Genomic Organization of the Adrenoleukodystrophy Gene

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Partial deletions of putative adrenoleukodystrophy (ALD) gene in Japanese ALD patients

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Mutational analysis of patients with X-linked adrenoleukodystrophy

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