( ( ( A ( new ( protozoan pathogen ) ) ) ( of humans ) ) . )
(ROOT (NP (NP (DT A) (JJ new) (NN protozoan) (NN pathogen)) (PP (IN of) (NP (NNS humans))) (. .)))
A new protozoan pathogen of humans.
(ROOT (S (NP (NNS Trichomoniasis)) (VP (VBZ is) (VP (VB cause) (PP (IN by) (NP (DT a) (NN protozoa))))) (. .)))