[1] Harvard Univ, Brigham & Womens Hosp, Sch Med, Pulm & Crit Care Med, Boston, MA 02115 USA
[2] St Andrea Hosp, ASL VC, Anesthesia & Intens Care, Vercelli, Italy
[3] Katholieke Univ Leuven, Dept Clin & Expt Med, Lab Resp Dis, Leuven, Belgium
[4] Semmelweis Univ, Dept Pulmonol, H-1085 Budapest, Hungary
[5] Univ Bergen, Dept Clin Sci, Bergen, Norway
[6] Univ London Imperial Coll Sci Technol & Med, Natl Heart & Lung Inst, Airway Dis Infect Section, London, England
[7] Univ Heidelberg Hosp, Dept Pneumol & Crit Care Med, Thoraxklin, Heidelberg, Germany
[8] Maastricht Univ, Dept Pharmacol & Toxicol, NL-6200 MD Maastricht, Netherlands
[9] Med Univ Silesia, Sch Med Katowice, Dept Pneumol, Katowice, Poland
[10] Inst Occupat Med & Environm Hlth, Sosnowiec, Poland