[1] Pulm Res Inst Southeast Michigan, Farmington Hills, MI USA
[2] Univ Ferrara, Dept Med Sci, Res Ctr Asthma & COPD, Ferrara, Italy
[3] Univ Texas San Antonio, Hlth Sci Ctr, Pulm Med & Crit Care, San Antonio, TX USA
[4] South Texas Vet Hlth Care Syst, San Antonio, TX USA
[5] Clin Res Inst Southern Oregon, Medford, MA USA
[6] Pearl, Durham, NC USA
[7] Pearl, Morristown, NJ USA