Tokyo stocks were slightly lower Tuesday morning on renewed fears that additional financial sanctions against Russia may spur commodity prices to rise further, although investors refrained from making large moves as they awaited the results of the U.S. Federal Reserve minutes later in the week. The 225-issue Nikkei Stock Average fell 28.17 points, or 0.10 percent, from Monday to 27,708.30. The broader Topix index was down 6.83 points, or 0.35 percent, at 1,946.80. The Tokyo bourse on Monday introduced the Prime, Standard and Growth markets to replace the four former trading segments — First S…