The Medical Research Network is expanding its presence in North America, with a raft of new hires and a move to new Chicago offices. MRN is expanding into Chicago after making a succession of senior appointments across the board. Following the appointment of Brent Barnett as senior director business development, the company is also bringing Roxann Becco as project manager and Emily Langley as project support manager. Brian Tresser, Senior Business Development Executive, will continue to be based in Atlanta.