Histological analysis
The colons tissue specimens were fixed in 10% formalin for 24 h, dehydrated, and paraffin-embedded. Hematoxylin and eosin (H&E) staining was performed to observe the colon tissue pathology under an optical microscope. The scoring criteria consisted of the following: 0, no evidence of inflammation; 1, low-level inflammation with scattered mononuclear cells (1-2 foci); 2, moderate inflammation with multiple foci of mononuclear cells; 3, high-level inflammation with increased vascular density and significant wall thickening; and 4, maximal inflammation with transmural leukocyte infiltration and loss of goblet cells. Additionally, periodic acid-Schiff stain (PAS) and Alcian blue staining techniques were used to examine the epithelial goblet cells, characterizing neutral mucin and acidic mucins, respectively. The Leica DM6B laser microdissection system was utilized to obtain images.