For the pulmonary fibrosis evaluation, the fibrosis index calculated based on MT staining, collagen deposition and active TGF-β1 expression detected by ELISA, and the expression of TGF-β1, α-smooth muscle actin (SMA), fibronectin, MMP-9, and TIMP-1 by western blotting. This evidence concerns the gene SMN1 and pulmonary fibrosis.