Study on the specificity of complement C5 for the postmortem diagnosis of myocardial infarction / 法医学杂志

In order to explore the specificity of complement C5 in the postmortem diagnosis of myocardial infarction, changes of C5 staining in normal, infarcted and other non-infarcted myocardia with direct or indirect myocardial injuries (myocarditis, mechanical asphyxia, electrocution, hemorrhagic shock, cardiac contusion and organophosphate poisoning) were studied with immunohistochemistry and image analysis. The results showed that positive C5 staining could be observed in groups of myocardial infarction and myocarditis, but not in groups of mechanical asphyxia, electrocution, hemorrhagic shock, cardiac contusion, and organophosphate poisoning. It is indicated that positive reaction of C5 could only be affected by myocarditis, which means that it was more specific for the diagnosis of myocardial infarction.

Complement and dengue haemorrhagic fever/shock syndrome.

The complement system is activated in DHF/DSS. The peak of activation and the presence of C3a and C5a anaphylatoxins coincided with the onset of shock and leakage. The levels of C3a correlated well with disease severity. This indicated an important role of the complement system in the pathogenesis of shock. Circulating immune complexes as assayed by two standard techniques were not detected in the majority of patients, and if detected were found in small amount. The role of circulating immune complexes in the activation of complement in DHF/DSS needs to be reinvestigated, and other possible mechanisms leading to complement activation should be sought.