Tokyo, Tokyo stocks lost ground Wednesday morning as investors opted to take profits following the Nikkei’s rise over the past two days, while a huge explosion in Beirut caused some concern.The 225-issue Nikkei Stock Average dropped 142.52 points, or 0.63 percent, from Tuesday to 22,431.14.The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, lost 8.97 points, or 0.58 percent, at 1,546.29.Land transportation, air transportation, and electric power and gas issues comprised those that declined the most by the morning break.