<qa>  What is the relationship between angiogenic cytokines and fibrinolytic activityAngiogenesis is a key process in the formation of exudative pleural effusions. Fluid loculation is common in parapneumonic effusion and is associated with depressed pleural fibrinolytic activity and poor clinical outcome. However, the relationship between angiogenic cytokines and fibrinolytic activity in the pleural space remains unclear. The researcherss hypothesis is that the levels of angiogenic cytokines were increased and associated with decreased fibrinolytic activity in parapneumonic effusions which may contribute to fibrin deposition and fluid loculation in the pleural space. 