Giving up all its initial gains, the Sensex at the Bombay Stock Exchange stood 11 points, or 0.1 percent in negative territory, at 18,215 in volatile afternoon trade, a short while ago. Earlier in the morning, however, the Sensex had opened with a gain of 93 points, or 0.5 per cent, at 18,320, on fresh buying by funds and retail investors. The Sensex had lost over 810 points in the previous five trading sessions.Other Asian markets in Japan, China, South Korea, Hong Kong, Indonesia and Singapore were trading mixed, today. But the US Dow Jones Industrial Average had climbed 0.4 per cent, to close at a fresh record high in yesterday's trade.