Cerebral blood flow and the secondary growth of brain tissue necrosis after trauma.

A local brain tissue necrosis from trauma progresses during the following 24 hours or longer. A decrease in cerebral blood flow has been observed both in the necrotic as well as adjacent cortical region, which may influence expansion of the lesion into the perifocal brain tissue. Currently the regional cortical blood flow (rCBF) was assessed by using scanning laser Doppler fluxmetry. Brain tissue necrosis was induced by a highly standardised cold lesion. We attempted to inhibit the development of posttraumatic ischemia in and around the focal lesion by infusion of a hypertonic/hyperoncotic saline/starch solution. The infusion therapy resulted in a temporary improvement of posttraumatic blood flow in both necrotic and distant cortical regions. However, the expansion of the focal necrosis was not reduced. Additional investigations are in progress to determine whether further amelioration with a longer duration of rCBF increase is effective in combination with methods of neuroprotection to inhibit the secondary lesion growth after a traumatic insult.

Size and composition of liver vitamin A reserves of human beings who died of various causes.

Postmortem livers from 77 "normal" persons, 37 patients with neoplastic disease, 10 subjects with liver insufficiency, and 7 infants were analysed for free and esterified retinol. The average concentrations of total vitamin A for the members of each group were 597, 551, 289, and 162 micrograms/g wet liver, respectively. Compared with corresponding control values, both cancer victims and patients with liver disease had significantly lower hepatic vitamin A levels. With regard to the composition of the liver vitamin A reserves, our results show that approximately 97% of this vitamin was present as retinyl ester. Additionally, minute amounts of retinol were also found in most of the liver specimens analysed. In "normal" subjects the major ester fraction recovered was palmitate/oleate followed by stearate and myristate/linoleate. By contrast, the second most abundant fatty acid in the retinyl ester fraction of cancer victims was myristic/linoleic acid together with significantly smaller quantities of stearic acid. In tissue samples obtained from patients with liver disorders, however, the myristate/linoleate fraction was increased and therefore nearly equal amounts of both retinyl stearate and myristate/linoleate were present.