The top pre-market NASDAQ stock market gainers are: Bucyrus International, Isilon Systems, Mediacom Communications, Telestone Technologies, Heartware International, GTSI, Amtech Systems, EDAP TMS, LJ International, and Joy Global.

Bucyrus International Inc. (BUCY) surged 29.56 percent to $90.20 in the pre-market session after the company has agreed to be acquired by Caterpillar Inc. (CAT) for about $8.6 billion, including net debt. Bucyrus shareholders will receive $92 per share, $7.6 billion in aggregate consisting of all cash.

Isilon Systems, Inc. (ISLN) soared 28.68 percent to $33.83 in the pre-market trading after it agreed to be acquired by EMC Corp. (EMC) for $33.85 a share in cash or about $2.25 billion, net of Isilon's existing cash balance.

Mediacom Communications Corp. (MCCC) improved 24.05 percent to $8.51 in the pre-market session after it agreed to be bought by founder and Chief Executive Officer Rocco Commisso for $8.75 a share in cash. The deal is expected to be completed in the first half of 2011.

Telestone Technologies Corp. (TSTC) grew 20.22 percent to $14.45 in the pre-market trading. The company's third quarter profit was $12.1 million or $1.14 a share, up from $4.2 million or 41 cents a share last year. Revenue rose to $43.1 million from $18.9 million. Analyst expects earnings of 51 cents a share on revenue of $33.57 million.

Telestone reaffirmed its guidance of $129.4 million in revenue, $22.9 million in net income and $2.17 in earnings per share for the 2010 year. Analyst expects profit of $1.79 a share on revenue of $111.11 million.

Heartware International Inc. (HTWR) gained 18.50 percent to $85.63 in the pre-market trading. The company said it achieved primary endpoint with 92 percent success in pivotal bridge to heart transplantation study, ADVANCE.

GTSI Corp. (GTSI) rose 15.74 percent to $5.22 in the pre-market session. The company's earnings for the third quarter were $5.9 million or 62 cents a share, up from $3.8 million or 39 cents a share last year. Sales rose 13.2 percent to $237.4 million.

Amtech Systems Inc. (ASYS) increased 14.24 percent to $19.74 in the pre-market trading. The company's fourth quarter earnings were $5.4 million or 58 cents a share, compared to a loss of $201,000 or 2 cents a share last year. Revenue rose to $45.4 million from $11.7 million.

Amtech expects fiscal 2011 revenues to surpass $200 million, a greater than 67 percent increase from fiscal 2010, with first quarter revenues in range of $44 million to $46 million.

EDAP TMS SA (EDAP) moved up 7.65 percent to $3.52 in the pre-market session.

LJ International Inc. (JADE) rose 7.29 percent to $5.59 in the pre-market trading.

Joy Global, Inc. (JOYG) gained 7.06 percent to $77.49 in the pre-market session.

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