Associated Press, May 21, 2010 Chicago - Nurses at University of Chicago Medical Center have voted to join a new union and hope to reopen talks with the hospital on staffing issues. The hospital's registered nurses voted Thursday to switch to National Nurses United, a national union. They had been represented by the Illinois Nurses Association. The vote was conducted by the National Labor Relations Board. Union leaders say they'll push for changes in minimum staffing ratios. The union also wants an end to rotations in which nurses shift between working days and nights. The hospital and nurses recently agreed on a contract, which nurses approved in April. Hospital officials say current nurse-to-patient staffing levels are in line with other academic medical centers locally and nationwide. Copyright 2010 Associated Press. All rights reserved.