The Sensex at the Bombay Stock Exchange rose a slim 18 points, or 0.1 per cent, to 17,169 in early trade, today, on selective buying by funds, ahead of the Reserve Bank's monetary policy announcement. Later, after a surprise 50 basis points rate cut by the apex bank, the Sensex jumped 222 points in late morning trade. Afterwards, the Sensex partially pared those gains, to stand 160 points, or 0.9 per cent in the green, at 17,311 in very volatile afternoon trade, a short while ago. But other Asian markets in Japan, China, Hong Kong, Singapore, South Korea, and Taiwan were down by between 0.1 percent and 1.7 percent, today, as soaring Spanish borrowing costs reignited investor nervousness over euro zone debt. The US Dow Jones Industrial Average had gained 0.6 per cent, overnight.