A company that operates 13 Ruby Tuesday franchised restaurants across the Midwest filed for bankruptcy with affiliates that struggled under $135.7 million worth of combined debt, Dow Jones DBR Small Cap reported yesterday. Four companies tied to RT Midwest Holdings LLC filed for chapter 11 protection Wednesday in the U.S. Bankruptcy Court in Minneapolis, listing only $15.4 million worth of assets related to the chain of casual dining restaurants it operates. The company, which is based in the southwest Minneapolis suburb of Chaska, saw its year-end revenue total fall 9 percent to $35.2 million last year, according to court papers. Bankruptcy Judge Gregory F. Kishel has been assigned the case for RT Midwest Holdings, which was given the number 12-43626.