The Nikkei stock index on Thursday briefly topped the 60,000 line for the first time, lifted by some heavyweight technology shares, but ended lower on concerns over overheating.The 225-issue Nikkei Stock Average ended down 445.63 points, or 0.75 percent, from Wednesday at 59,140.23. The broader Topix index finished 28.61 points, or 0.76 percent, lower at 3,716.38.On the top-tier Prime Market, the main decliners were nonferrous metal, air transportation and service issues.The U.S. dollar strengthened to the upper 159 yen range in Tokyo, as investors fled to safety following a surge in crude …READ FULL ARTICLE