Sen. Charles E. Grassley of Iowa, the ranking Republican on the Senate Finance Committee, is seeking information from the nonprofit University of Chicago Medical Center about jobs held by Sen. Barack Obama's wife and one of the senator's best friends. Grassley sent the center a letter saying he was "troubled" by recent news reports about the hospital's efforts to steer patients with non-urgent complaints away from the center's emergency room to local clinics. Michelle Obama was a key figure behind the initiative. The medical center said in a statement that it was working on a response to the letter.