Studies on the biocompatibility of bacterial cellulose

Bacterial cellulose was functionalized with a chimeric protein containing a cellulose-binding module and the adhesion peptide Arg-Gly-Asp. Small-diameter bacterial cellulose membranes were produced and subcutaneously implanted in sheep for 1–32 weeks. The implants triggered a biological response similar to other high surface-to-volume implants. There were no significant differences in the inflammation degree between the bacterial cellulose coated with the recombinant protein Arg-Gly-Asp–cellulose-binding module and the native bacterial cellulose. The implants were considered to be mildly irritating to the tissue compared to the negative control sample (expanded polytetrafluoroethylene). The analysis of the fluorescence microscopy revealed that, apart from increasing cell adhesion, the presence of Arg-Gly-Asp stimulated an even cell distribution, while the cells on the untreated bacterial cellulose seemed to form aggregates. Furthermore, the cells on the Arg-Gly-Asp–treated bacterial cellulose presented a more elongated morphology. Mechanical tests indicated that the small-diameter bacterial cellulose tubes were more elastic than the human arteries and veins.This work is funded by FEDER Funds through the Operational Programme for Competitiveness Factors COMPETE and National Funds through FCT - Foundation for Science and Technology under the Strategic Project PEst-C/AGR/UI0115/2011, the project PTDC/EBB-EBI/112170/2009 and under the PhD grant reference SFRH/BD/64838/2009. This work was also supported by Fundacao para a Ciencia e Tecnologia (FCT), Ministerio da Educacao e da Ciencia, Portugal, through the research Project PTDC/DES/104036/2008 and by QREN No. 1372 para Criacao de um Nucleo I&DT para Desenvolvimento de Produtos nas Areas de Medicina Regenerativa e de Terapias Celulares - Nucleo Biomat & Cell.Fabia K. Andrade is the recipient of a fellowship from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, Brazil). Fabia K Andrade and Nuno Alexandre contributed equally to this work

Multi-Dimensional Prioritization of Dental Caries Candidate Genes and Its Enriched Dense Network Modules

A number of genetic studies have suggested numerous susceptibility genes for dental caries over the past decade with few definite conclusions. The rapid accumulation of relevant information, along with the complex architecture of the disease, provides a challenging but also unique opportunity to review and integrate the heterogeneous data for follow-up validation and exploration. In this study, we collected and curated candidate genes from four major categories: association studies, linkage scans, gene expression analyses, and literature mining. Candidate genes were prioritized according to the magnitude of evidence related to dental caries. We then searched for dense modules enriched with the prioritized candidate genes through their protein-protein interactions (PPIs). We identified 23 modules comprising of 53 genes. Functional analyses of these 53 genes revealed three major clusters: cytokine network relevant genes, matrix metalloproteinases (MMPs) family, and transforming growth factor-beta (TGF-β) family, all of which have been previously implicated to play important roles in tooth development and carious lesions. Through our extensive data collection and an integrative application of gene prioritization and PPI network analyses, we built a dental caries-specific sub-network for the first time. Our study provided insights into the molecular mechanisms underlying dental caries. The framework we proposed in this work can be applied to other complex diseases