Gains extended at midday

The markets extended its gains during the midday with the Dow leaping 190 points to 18,149. Nasdaq soared 41 points to 5,033.

On the upside

Envivio (Nasdaq: ENVI) narrowed losses for the fourth quarter.

Viggle (Nasdaq: VGGL) founder and chief executive Robert F.X. Sillerman offered to acquire 25% of the company's Wetpaint business for $10 million in cash.

Bargain hunters lifted shares of National Bank of Greece (NYSE: NBG).

On the downside

Profit taking weighed down shares of Arotech (Nasdaq: ARTX).

Youku Tudou (NYSE: YOKU) widened losses significantly for the fourth quarter.

Investors locked in profits on Coronado Biosciences (Nasdaq: CNDO).

In the broad market, advancing issues outpaced decliners by a margin of more than 4 to 1 on the NYSE and by a margin of nearly 2 to 1 on Nasdaq. The broader S&P 500 climbed 19 points to 2109. Bitcoin eased a fraction to $259.