[1] Royal Brompton Hosp, Natl Heart & Lung Inst, London SW3 6LY, England
[2] Univ Ferrara, I-44100 Ferrara, Italy
[3] Univ Paris Sud, Fac Med, F-94276 Le Kremlin Bicetre, France
[4] Hop Antoine Beclere, AP HP, Ctr Natl Reference Hypertens Pulm Severe, Serv Pneumol & Reanimat Resp, F-92140 Paris, France
[5] Univ London Imperial Coll Sci Technol & Med, Royal Brompton Hosp, Lung Pathol Unit, London, England
[6] Univ London Imperial Coll Sci Technol & Med, Fac Med, Natl Heart & Lung Inst, Dept Cell & Mol Biol,Airways Dis Sect, London, England