Tokyo stocks opened lower Wednesday, the first trading day of 2023, weighed down by overnight losses on Wall Street and concern that the Bank of Japan could move further toward monetary tightening. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 421.32 points, or 1.61 percent, from Friday to 25,673.18. The broader Topix index was down 26.92 points, or 1.42 percent, at 1,864.79. Japanese financial markets were closed Monday and Tuesday due to the New Year holidays. On the top-tier Prime Market, decliners were led by mining, marine transportation, and rubber product i…