, xxx is a blast of adrenalin , 
(ROOT (S (, ,) (NP (NN xxx)) (VP (VBZ is) (NP (NP (DT a) (NN blast)) (PP (IN of) (NP (NN adrenalin))))) (, ,)))
(ROOT (S (, ) (NP (NN )) (VP (VBZ ) (NP (NP (DT ) (NN )) (PP (IN ) (NP (NN ))))) (, )))