(Tuesday’s/9.30H/CEB anfitheatre)
Eva Pinho, Development of new antimicrobial textile for wound dressing
Normally, the skin is capable of restore the tissue integrity, after wound injury. However, the deposition of bacteria on the wound site results on infection causing pain and healing delay. To control bacteria proliferation, antimicrobial textiles have been developed, although, the continuous use of such textiles can give rise to adverse side-effects, including sensitization, skin ecology disturbances and cytotoxic effects. Therefore, an appropriate balance should be maintained between the benefits and potential risks of such technologically-driven materials. Therefore, we propose to develop a new antimicrobial textile for wound dressing using natural plant extracts with bioactive proprieties besides the antimicrobial activity. It is expected that this material will be friendlier to the skin when compared to the ones already commercialized. The assessment of the antimicrobial activity of these textiles is a required step. Although, several standard methods were published to assess textiles antimicrobial activity, they are very time and material consuming and have some shortcomings with regard to the real conditions of use. Therefore, the first task of this work was to adapt and optimize the method described on JIS L 1902:2008-Testing for antibacterial activity and efficacy on textile products, the most commonly used standard.
Alexandre Leitão, Bacterial cellulose/polyvinyl alcohol nanocomposite as a biomaterial for small caliber vascular grafts
According to the American Heart Association, in 2006, one of every six deaths in the USA was due to coronary heart disease. They report that for the same year 448000 coronary bypass surgeries were performed on 253000 patients (American Heart Association, 2010). Atherosclerosis consists of a narrowing of blood vessels due to the accumulation of fatty materials, such as cholesterol, on the walls of arterial blood vessels associated with an inadequate removal of the built up material. Severe occlusions require vascular graft surgeries, a surgical procedure that creates an alternative channel for blood flow, in order to bypass the occluded portion of the vessel. Autologous grafts are the first choice as graft material; however, due to either pre-existing conditions or previous bypass surgery availability commonly poses a problem. Alternatively, synthetic materials can, and have, been used such as Dacron or ePTFE. The currently available synthetic graft materials perform well as large-caliber vessels (>6mm) however tend to fail at low calibers due to thrombosis and general mismatch of mechanical properties. Endothelial coverage of these synthetic grafts, which would minimize thrombosis, is somewhat limited to the tissue adjacent regions of the synthetic graft. Attempts have been made towards seeding the luminal side of these grafts with endothelial cells prior to their use. Herein lies a need for the development of a viable biomaterial with appropriate mechanical and biochemical properties and that can serve as a small caliber prosthetic material for vascular surgery with potential towards serving as a tissue engineering scaffold and towards that objective we propose a bacterial cellulose/polyvinyl alcohol nanocomposite.
