Interstate Distribution Centers Inc. (formerly Interstate Dress Carriers), whose main address is listed as Secaucus, N.J., has discontinued its trucking operations from its sprawling Mahoning Township terminal. Officials of Teamster Union Local 773 said that layoffs have resulted from the move. They did not know how many employees are affected by layoffs. The loading and unloading aspect of the business was transferred to terminals in Myerstown, Lebanon County, and Wilkes-Barre.