Adult, Aged, Azathioprine, Caco-2 Cells, Colitis, Ulcerative, Colon, Crohn Disease, DNA Primers, Female, Gastrointestinal Agents, Gene Expression Profiling, Genetic Markers, Humans, Male, Mesalamine, Middle Aged, Oligonucleotide Array Sequence Analysis, RNA, Messenger, Reverse Transcriptase Polymerase Chain Reaction