According to the Associated Press, GlaxoSmithKline is restructuring its U.S. operations, starting with reducing its U.S. sales force by 1,000. A spokeswoman says the company also will switch from having dual U.S. headquarters, in Philadelphia and in Research Triangle Park, N.C., to operating just the North Carolina headquarters. GlaxoSmithKline has about 8,500 U.S. sales representatives. It plans to cut about 1,800 of those, but at the same time beef up its vaccine sales force to end up with a total of about 7,500 U.S. sales representatives. Workers losing jobs are being told this week and will be out of work by year''s end.