The use of acellular fish skin grafts (FSG) for the treatment of burn wounds is becoming more common due to its beneficial wound healing properties. In our previous study we demonstarted that FSG... Show moreThe use of acellular fish skin grafts (FSG) for the treatment of burn wounds is becoming more common due to its beneficial wound healing properties. In our previous study we demonstarted that FSG is a scaffold biomaterial that is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) conjugated to phosphatidylcholines. Here we investigated whether EPA and DHA derived lipid mediators are influenced during the healing of burn wounds treated with FSG. Deep partial and full thickness burn wounds (DPT and FT, respectively) were created on Yorkshire pigs (n = 4). DPT were treated with either FSG or fetal bovine dermis while FT were treated either with FSG or cadaver skin initially and followed by a split thickness skin graft. Punch biopsies were collected on days 7, 14, 21, 28 and 60 and analyzed in respect of changes to approximately 45 derivatives of EPA, DHA, arachidonic acid (AA), and linoleic acid (LA) employing UPLC-MS/MS methodology. Nine EPA and DHA lipid mediators, principally mono-hydroxylated derivatives such as 18-HEPE and 17-HDHA, were significantly higher on day 7 in the DPT when treated with FSG. A similar but non-significant trend was observed for the FT. The results suggest that the use of FSG in burn wound treatment can alter the formation of EPA and DHA mono hydroxylated lipid mediators in comparison to other grafts of mammalian origin. The differences observed during the first seven days after treatment indicates that FSG affects the early stages of wound healing. Show less
This thesis explores cognitive vulnerability to depression and the interplay between genetic and environmental influences. Cognitive vulnerability to depression is characterized by negative... Show moreThis thesis explores cognitive vulnerability to depression and the interplay between genetic and environmental influences. Cognitive vulnerability to depression is characterized by negative patterns of information processing. One aspect is cognitive reactivity - the tendency to respond with maladaptive thoughts when mood is challenged. Vulnerable individuals also show negative cognitive biases in emotion perception and attention, and impaired decision-making. How one processes personal and socially relevant information plays an important role in the development and maintenance of depression. The first part of the thesis reports how the interplay between genes and environment affects cognitive reactivity and emotional information processing. We observed that genes and environmental stressors interact to determine a person’s vulnerability to depression or resilience. Cognitive reactivity was also found to be a residual vulnerability factor in individuals with history of suicidal tendencies. The second part of the thesis is comprised of two experimental manipulations on emotional cognition. Effects of omega-3 fatty acid supplementation were examined on mood and cognition of healthy participants and recovered depressed individuals. Omega-3 fatty acids can have selective effects on mood and cognition of individuals, but the pathways through which this happens remain to be investigated. Show less
