Japanese stocks opened higher Wednesday, as reports that Italian Prime Minister Silvio Berlusconi would resign eased concerns of the country\'s debt problems. In the first 15 minutes of trading, the benchmark 225-issue Nikkei Stock Average rose 81.63 points, or 0.94 percent, from Tuesday to 8,737.14. The broader Topix index of all First Section issues on the Tokyo Stock Exchange gained 7.26 points, or 0.98 percent, to 745. 29.