The Sensex at the Bombay Stock Exchange lost 52 points, or 0.3 per cent, to 17,487 in opening trade, this morning, as funds and retail investors resorted to mild profit-booking, amid subdued regional bourses. Later, the Sensex remained weak, and stood 45 points, or 0.3 percent in the red, at 17,493 in afternoon deals, a short while ago.Other Asian markets in Japan, Hong Kong, Indonesia, Singapore, South Korea and Taiwan were down by between 0.1 percent and 0.9 percent, today, after rate cuts by central banks in China and Europe failed to enthuse investors. Over in the US, the Dow Jones Industrial Average had slipped 0.4 per cent in yesterday's trade.