Haemoptysis is a potentially life-threatening symptom, which require immediate management. Haemoptysis is a challenging situation because the potential numerous causes lead to strongly different therapeutic options (medical, surgical, systematic embolization). When haemoptysis occurred at the acute phase of pulmonary embolism, anticoagulation should be stopped and inferior vena cava filter is justified. Based on a case report of massive haemoptysis related to pulmonary infarction (i.e., no other causes) in a patient with a unprovoked intermediate high-risk pulmonary embolism, we describe the dilemma set in the paradox between the need for stopping anticoagulation and the need to treat the cause of haemoptysis which is also anticoagulation. If anticoagulation should be stopped, however, the optimal management regarding the use of specific reversal agents or prothrombotic plasma concentrates remains uncertain and weakly documented. After haemoptysis has been resolved, there is also uncertainty on restarting anticoagulation modalities. Regarding long-term management, the decision to stop at three months or to prolong indefinitely based on international recommendation is also challenging in the case of unprovoked severe pulmonary embolism. In this particularly high risk situation, multidisciplinary expertise is essential.

The structural and dynamical properties of PPARγ receptor in a complex with either partial or full agonists have been intensively studied but little is known about the receptor antagonistic conformation. A composition of microsecond accelerated molecular dynamics (aMD) simulation show that like partial agonists a non-covalent PPARγ full antagonist can bind in different modes of similar population size and free energies of binding. Four different and periodically exchanging ligand conformations are detected and described. The studied antagonist interacts with different receptor substructures and affects both the co-activator and the Cdk5 phosphorylation sites and, presumably, the natural complex with the DNA. However, no significant changes in the conformational states of the activation helix 12, and in particular an antagonist orientation, have been recorded. Finally, our results show also that the aMD approach can be successfully used in recovering the possible binding modes, considering fully the receptor flexibility, and is not dependent on the starting conformation.