Suchergebnisse

First published: 1 September 2013 ; The inefficacy of the currently used therapies in achieving the regeneration ad integrum of the periodontium stimulates the search for alternative approaches, such as tissue-engineering strategies. Therefore, the core objective of this study was to develop a biodegradable double-layer scaffold for periodontal tissue engineering. The design philosophy was based on a double-layered construct obtained from a blend of starch and poly-ε-caprolactone (30:70 wt%; SPCL). A SPCL fibre mesh functionalized with silanol groups to promote osteogenesis was combined with a SPCL solvent casting membrane aiming at acting as a barrier against the migration of gingival epithelium into the periodontal defect. Each layer of the double-layer scaffolds was characterized in terms of morphology, surface chemical composition, degradation behaviour and mechanical properties. Moreover, the behaviour of seeded/cultured canine adipose-derived stem cells (cASCs) was assessed. In general, the developed double-layered scaffolds demonstrated adequate degradation and mechanical behaviour for the target application. Furthermore, the biological assays revealed that both layers of the scaffold allow adhesion and proliferation of the seeded undifferentiated cASCs, and the incorporation of silanol groups into the fibre-mesh layer enhance the expression of a typical osteogenic marker. This study allowed an innovative construct to be developed, combining a three-dimensional (3D) scaffold with osteoconductive properties and with potential to assist periodontal regeneration, carrying new possible solutions to current clinical needs . ; The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013; under Grant Agreement No. REGPOT-CT2012-316331-POLARIS) and from the Portuguese Foundation for Science and Technology (FCT; Grant No, MIT/ECE/0047/2009). Joao Requicha acknowledges the FCT for his PhD scholarship ( Grant No. ...

Poster abstract publicado em: Mycoses. 2017;60(Suppl. S2):130-1. Disponível em:http://onlinelibrary.wiley.com/doi/10.1111/myc.12674/epdf ; Although exposure to fungi and their metabolites, by inhalation, contact and ingestion has often been addressed, it rarely made way into safety regulation. The EU drinking water directive 98/83/EC and the national legislation in the European countries - with very few exceptions - fails to address fungi explicitly. The same is valid also for European regulatory Directive 2006/7/EC, currently undergoing its second revision with no plan to introduce fungi, yet again. Both Directives address microbiological safety of drinking and bathing / recreational waters by monitoring of bacterial parameters indicating faecal contamination, and correlating with gastro-intestinal illness but leaving behind other microbes and several emerging pathogens and other pathologies. This study assesses the European drinking and bathing water regulations and sand; it evaluates background information, and underpinning missing fungal parameters that (may) affect human health. ; The work of Wieland Meyer was supported by the National Health and Medical Research Council of Australia (NH&MRC) grants APP1031952 and APP1121936. ; info:eu-repo/semantics/publishedVersion

First published online: 2012 ; Gellan gum (GG)-based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine-tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG-MA) and high-acyl gellan gums (HA-GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA-GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA-GG content induced greater weight loss in the GG-MA/HA-GG formulation compared to GG-MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein-AM and ATP assays. Results showed that tunable GG-MA/HA-GG hydrogels were non-cytotoxic and supported viability of rabbit NP cells. ; The authors thank the Portuguese Foundation for Science and Technology (FCT) for financial support through POCTI and FEDER programmes. This work was also conducted with the support of the European Union funded Collaborative Project Disc Regeneration (NMP3-LA-2008-213904), MBC(A04003) and the World Class University project ...