The formalin-infused lungs were embedded in paraffin wax
blocks and sliced into 6 lm-thick sections. The slides were
examined under a light microscope after staining with haematoxylin
and eosin. The scoring of the airway inflammation was
blindly investigated by two separate investigators. A standard
scale (0–3) was used to evaluate the severity of perivascular
and peribronchial inflammation (Park et al., 2001) and to
assign value: 0 for no evident inflammation, 1+ for foci or
infrequent cuffing with inflammatory cells, 2+ if most bronchi
or vessels were surrounded by a thin layer, and 3+ for the
most severe inflammation (more than five cells deep) of inflammatory
cells. The average of the peribronchial and perivascular
inflammation scores was used to define total lung
inflammation.
2.9. Statistical analysis
Statistical Package for the Social Sciences