TNF and ulcerative colitis: As the severity of ulcerative colitis is positively correlated with the levels of certain inflammatory mediators and the production of proinflammatory cytokines in the inflamed colon, we mainly focused on the abnormal expression of TNF-α, INF-γ, IL-1β, IL-8, IL-12, NOS, and TLR-4, which are well-known inflammatory markers that play important roles in the pathogenesis of ulcerative colitis.