jason sedakis joining a long line of cast members leaving. he is famous for playing joe biden, howard dean, and, of course, wolf, who by the way tweeted, with sedakis leaving, who should play me next? got to watch, "situation room," 5:00 eastern to hear wolf's thoughts. it is a miracle l that an infantry sergeant came home from vietnam alive, and he has started a program designed to help other vets. dr. sanjay gupta has his story in this week's "human factor." >> reporter: it was 1968. infantry platoon sergeant irvin ramirez was on patrol in vietnam. >> as we were going out, going by the rice paddies in the delta, i hear mortar shells going off and machine guns going off. next thing i know i found myself falling face first into a rice paddy. that's it. two days later, i woke up in a saigon military hospital. they told me i was lucky.