Acetylsalicylic Acid Produces Different Effects on the Production of Active Oxygen Species by Activated Platelets in Different Inflammatory Diseases.

We studied the effect of acetylsalicylic acid on ROS generation by platelets in patients after surgical interventions and in patients with bronchial asthma was studied. Platelets stimulated with platelet-activating factor are characterized by weak luminol-enhanced chemiluminescence in healthy people and patients after operations with laparoscopic incisions. Addition of platelet activation factor to platelet samples from patients after open abdominal surgery caused intensive chemiluminescence that was suppressed after platelet incubation with acetylsalicylic acid. At the same time, platelets of patients with aspirin-sensitive asthma did not respond to addition of platelet activating factor, but after incubation with acetylsalicylic acid, an intensive burst of chemiluminescence was detected with a maximum in 5-10 sec after the addition of a platelet-activating factor. In patients with bronchial asthma tolerant to aspirin, platelet activation factor did not induce chemiluminescence irrespective of incubation with acetylsalicylic acid.

Visualization of reversible macromolecular reactions in an analytical ultracentrifuge.

It has been shown that the saw-like disturbances of sedimentation observed in an analytical ultracentrifuge are not caused by convective disturbances of the solution but result from a special type of intermolecular reaction of reversible association/dissociation. A qualitative theory of saw-like anomalies has been suggested and the sedimentation and kinetic conditions of their origin have been indicated. Such reactions are a frequent occurrence in the serum of patients affected with rheumatic diseases and acute myocardial infarction. Experimental data indicate the involvement of immunoglobulins (viz., low-affinity antibodies) which form reversible immune complexes. Saw-like sedimentation patterns, especially those of the schlieren type, are a direct testimony to reversible association/dissociation reactions in macromolecular solutions, whereas other experimental methods provide only oblique evidence.