Directly after fighting (and losing to) Auntie Biotic, I started a conversation, but no entries were available. Since it was not possible to exit the conversation or load a game, I had to forcibly quit the game, and restart from my last save game. It may have been caused by skipping through the last dialog by right clicking after losing (I'm not sure wether or not I did that).
I haven't tried reproducing it; after loading I took care not to go to fast, and everything worked fine. I attached a screen shot of the situation.