The Sensex at the Bombay Stock Exchange opened 105 points, or 0.6 per cent higher, at 18,724, this morning, with IT stocks leading the gains, after TCS posted an impressive quarterly net profit. But the Sensex soon surrendered all its initial gains, and stood 53 points, or 0.3 percent in negative territory, at 18,565, in volatile trade, a short while ago.Other markets in Japan, China, Indonesia, Taiwan, and South Korea were up by between 0.1 percent and 1 percent, today.