Blood-gas exchange devices.
Explore the source record for details and available documents.
Biocompatible Materials↗
Biomedical subjects
B F Brian
Publications and source records attributed to B F Brian.
Metabolic adjustments to dynamic hypoxic hypoxemia in feline brain tissue.
Three different metabolic models were incorporated in a compartmental simulation of brain tissue pO2 response to rapid changes in arterial pO2. The first was the frequently utilized constant metabolism assumption. The second model was a 4-step kinetic simplification of glucose conversion to CO2 with an intermediate reversible reaction of pyrovate to lactate. The most sophisticated model was a new 11-step reaction scheme with the same start and end points accounting for glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation. A unique representation was derived for the oxygen consumption depending on reduced cytochrome a3+(3) consistent with diverse observations in the literature. The theoretical predictions were compared to previously published cortical tissue pO2 recordings from detailed experiments with pentobarbital anesthetized cats. The 11-step metabolic model invariably provided the best match between the theoretical calculations and the observed responses. These results indicate that cellular metabolism rapidly adjusts to changes in O2 in a manner which reduces the tissue pO2 fluctuation. In concert with the large compensatory arterial blood flow response there was extensive damping of intracellular pO2 compared to arterial O2 changes.
Animals↗
Augmented hemoperfusion for hyperbilirubinemia.
Exchange transfusions and phototherapy are used to treat hyperbilirubinemia, each method having its own disadvantages. Hemoperfusion with coated activated charcoal (CAC) produces low removal rates due to the strong binding of bilirubin to albumin. Biocompatible chemical agents were investigated to selectively unbind the bilirubin into solution just prior to CAC exposure. In batch mock solution tests, the addition of sodium benzoate resulted in a 69% equilibrium bilirubin removal at 50 mM and 96% removal at 100 mM. During flow tests, adsorptive removal of sodium benzoate was so rapid that the CAC had to be pretreated with sodium benzoate solutions. In the absence of sodium benzoate, the outlet bilirubin was 50% of the inlet concentration at the passage of one void volume, with a rapid increase to 70% (30% removal). With sodium benzoate at 100 mM, the same 50% outlet/inlet percent was observed at one void volume throughput, but the outlet concentration fell to 6% of the inlet at 12 column void volumes (94% removal). Similar experiments with bovine plasma/blood and human plasma resulted in an average increase in bilirubin removal of 25% for the bovine and human plasma and 35% for the bovine blood at 100 mM benzoate. A significant decrease in platelet aggregation was measured with the addition of sodium benzoate, which makes this augmented hemoperfusion removal of bilirubin clinically attractive.
Benzoates↗