The BSE Sensex which gained 138 points in early trade was trading 104 points up at 17, 463 a short while ago.The wide-based National Stock Exchange index Nifty moved up by 38 points to 5,329. Brokers said sentiment buoyed after RBI slashed short-term lending rate by 0.50 per cent to 8 per cent yesterday and a firming trend on other Asian bourses, following overnight gains on the US market on easing concerns over Europe's debt crisis.In the Asian region, the Hong Kong's Hang Seng Index rose by 0.94 per cent and Japan's Nikkei Index was up by 1.67 per cent in morning trade today. The US Dow Jones Industrial Average ended 1.50 per cent higher in yesterday's trade.