No abstract

No abstract

We report the adaptation of a simple, precise chemical assay for vicinal hydroxyl groups to the determination of phosphatidylglycerol transbilayer distribution in small, unilamellar vesicles. Conditions are described under which the chemical procedure reveals only phosphatidylglycerol molecules exposed on the surface of intact phospholipid vesicles. Other assay conditions reveal all the phosphatidylglycerol in the vesicle. Vesicle size distributions have been determined by gel permeation chromatography. These and the phosphatidylglycerol distribution data have been used to estimate the lipid asymmetry in dipentadecanoylphosphatidylglycerol-dimyristoylphosphatidylcholine vesicles. The result obtained for 50 mol % phosphatidylglycerol is similar to earlier nuclear magnetic resonance estimates of the asymmetry in egg phosphatidylglycerol-egg phosphatidylcholine vesicles [Michaelson, D.

No abstract

Although antithrombin-3 (AT-3), a naturally-occurring inhibitor of thrombin, has been associated with a variety of thrombotic disorders, it has been studied in surgery and trauma. Three groups of patients were studied: Group I (20 patients) who underwent elective surgery; Group II (ten patients) who sustained moderate trauma: Group III (ten patients) who sustained severe trauma. Hypercoagulability panels were run preoperatively, intraoperatively, and postoperatively. Nine units of banked blood were also tested. The coagulation pattern changed during the stress, becoming hypercoagulable in proportion to the stress endured by the patient. In the severe trauma group, AT-3 fell significantly (p less than or equal to 0.002) in all patients, indicating extreme hypercoagulability. Three of these patients sustained thrombosis and loss of the involved extremity. The banked blood was found to be hypercoagulable. It appears that patients who sustain severe trauma, have multiple transfusions, and major operative procedures are at increased risk of developing postoperative thrombotic complications, including loss of limb.