Lars Jensen

ANIONIC GLYCEROPHOSPHOLIPIDS IN PLATELETS FROM ALCOHOLICS

Studies on ethanol-exposed animals have revealed changes in anionic phospholipids in brain membranes. The intention of this study was to investigate whether there was a similar effect on man. Assuming platelets to be an adequate model for CNS synaptosomes, concentration and fatty acid composition of anionic phospholipids, phosphatidylserine (PS) and phosphatidylositol (PI) in the platelet membrane from alcoholics after a debauche period were examined and compared to controls. Ethanol effects on neutral lipids were also analysed in order to obtain a comprehensive view. No quantitative difference was found in anionic phospholipids between alcoholics and controls. Fatty acid composition of individual phospholipids revealed significant changes which were more obvious in neutral phospholipids than in anionic. Oleic acid was increased and linoleic and arachidonic acids were decreased. After 1 week of detoxification, the abnormalities did not decrease, on the contrary they increased and total phospholipid concentration per platelet was significantly higher than in controls. It is concluded that the ethanol toxicity on bone marrow hampers the use of platelets as a model for synaptosomes but that the observed lipid abnormalities might play a major role in the impairment of platelet function in alcoholics.

Stairwell Flow Pressurization – A New Method

Pressurization is used to prevent smoke spread into a stairwell. The stairwell height is limited by the pressure to open doors, about 80 Pa, the pressure to prevent smoke spread, about 20 Pa and the outdoor-indoor temperature-induced pressure gradient, about 2 Pa/m. This limits the height to 30m ((80 20)/2). However, this limit can be increased by balancing the temperature-induced pressure gradient with an equal and opposite flow pressure gradient created by a flow passing through the whole stairwell.