The top after-market NASDAQ Stock Market gainers are: Zalicus, Pacific Biosciences of California, Optimer Pharmaceuticals, Micron Technology, and YRC Worldwide. The top after-market NASDAQ Stock Market losers are: MediciNova, Iridium Communications, Ascena Retail Group, Altra Holdings, and GSI Group.

Gainers

Zalicus Inc. (ZLCS) stock grew 5.77 percent to $2.20 in the after-market trading.

Pacific Biosciences of California, Inc. (PACB) stock gained 4.60 percent to $15 in the after-market trading.

Optimer Pharmaceuticals, Inc. (OPTR) stock increased 4.58 percent to $12.55 in the after-market trading.

Micron Technology Inc. (MU) stock gained 3.77 percent to $11.01 in the after-market trading, as its second quarter earnings and revenue topped Street view. Profit was $72 million or 7 cents a share, down from $365 million or 39 cents a share last year. Sales rose to $2.26 billion from $1.96 billion. Analysts had expected profit of 3 cents a share on revenue of $2.06 billion.

YRC Worldwide Inc. (YRCW) stock rose 1.97 percent to $2.07 in the after-market trading. YRC Inc., a unit of YRC Worldwide, said it will expand the size of its sales force with a nationwide hiring initiative in response to increased business levels and customer needs. YRC Inc. said it plans to hire as much as 100 additional salespeople nationwide.

Losers

MediciNova Inc. (MNOV) stock plunged 14.61 percent to $3.04 in the after-market trading, as it plans to offer units consisting of shares of its common stock and common stock purchase warrants in a firm-commitment underwritten public offering. There can be no assurance as to whether the offering may be completed or as to the actual size or terms of the offering.

Separately, MediciNova said it has priced a firm-commitment underwritten public offering of 2,750,000 units at a price to the public of $3.00 per unit for gross proceeds of $8.25 million. The warrants are exercisable immediately upon issuance, have a five-year term and an exercise price of $3.56 per share. Net proceeds, after estimated underwriting discount and assuming the warrants are not exercised, will be about $7.8 million. The offering is expected to close on or about March 29.

Iridium Communications Inc. (IRDM) stock slid 4.71 percent to $8.69 in the after-market trading.

Ascena Retail Group, Inc. (ASNA) stock declined 2.82 percent to $30.01 in the after-market trading.

Altra Holdings, Inc. (AIMC) stock decreased 2.40 percent to $20.76 in the after-market trading.

GSI Group Inc. (GSIG) stock moved down 2.39 percent to $10.54 in the after-market trading.