Surrendering all its initial gains, the Sensex at the Bombay Stock Exchange stood 14 points, or 0.1 percent in negative territory, at 19,341 in afternoon trade, a short while ago. Earlier in the morning, however, the Sensex had opened with a gain of 66 points, or 0.3 per cent, at 19,422, on fresh buying by funds and retail investors. The 30-share Sensex has lost more than 130 points in the past four trading sessions. Key stock indices in Japan, China, Singapore, South Korea, Hong Kong and Indonesia were trading mixed, today. The US Dow Jones Industrial Average had ended flat in yesterday's trade.