Tokyo stocks opened higher Wednesday, supported by overnight gains on Wall Street and better-than-expected earnings from some Japanese companies. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average rose 313.80 points, or 1.16 percent, from Tuesday to 27,392.28. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was up 22.67 points, or 1.20 percent, at 1,918.73. Gainers were led by air transportation, securities house and rubber product issues. At 9 a.m., the dollar fetched 114.73-74 yen compared with 114.63-73 yen in New York and 114.93-95 yen in…