HMGB1 and pneumonia: Nicotine has also been demonstrated to have deleterious effects on oxidative stress as well as significantly increase production of inflammatory markers, such as C-reactive protein, soluble intercellular adhesion molecule, and the danger signal machinery high-mobility group box 1 (HMGB1).3,5,9 This augmented state of inflammation may play a role in increased rates of perioperative infection and pneumonia.10