The top after-market NYSE gainers Wednesday were Western Asset Mortgage, SunTrust Banks, Best Buy Co, Trinity Industries and Krispy Kreme Doughnuts. The top after-market NYSE losers were Guess?, Inc, International Rectifier, Hewlett-Packard, Big Lots and Whitestone REIT.

Gainers:

Western Asset Mortgage Capital Corp. (WMC) shares surged 3.68 percent to $21.71 in the post-market trading. National Securities initiated coverage on shares of WMC with a “buy” rating.

SunTrust Banks Inc. (STI) shares surged 3.29 percent to $26.03 in the ost-market trading. The company announced Wednesday that the Federal Reserve has not objected to the Company's capital plan, which STI submitted in June in connection with the Comprehensive Capital Analysis and Review (CCAR).

Best Buy Co. Inc. (BBY) shares rose 2.71 percent to $18.20 in the post-market trading. The company announced Wednesday that its board of directors has authorized payment of a regular quarterly cash dividend of $0.17 per common share.

Trinity Industries Inc. (TRN) shares gained 2.15 percent to $29.95 in the post-market trading. The stock has a 52-week low of $19.10, a 52-week high of $36.09 and $2.32 billion in market capitalization.

Krispy Kreme Doughnuts (KKD) shares advanced 1.87 percent to $7.08 in the post-market trading. The company reported second quarter adjusted net profit of $8.2 million or $0.12 per share, up from $4.2 million or $0.06 per share and also topped Reuters' estimate of $0.05 per share.

Losers:

Guess? Inc. (GES) shares slumped 16.25 percent to $28.09 in the post-market trading after lowering its full year earnings guidance. The company currently expects full year earnings to be in a range of $2.15 to $2.30 per share on revenues of $2.62 to $2.65 billion, down from its prior estimate of $2.50 to $2.65 per share on revenues of $2.70 to $2.74 billion and also fell short of the analysts’ estimate of $2.59 per share.

International Rectifier Corp. (IRF) shares slumped 8.01 percent to $17.00 in the post-market trading. The company swung to a fourth quarter net loss of $68.19 million or $0.99 per share compared to the net profit of $39.63 million or $0.55 per share in the same period last year and also widely missed the analysts’ estimate of a loss of $0.15 per share.

Hewlett-Packard Co. (HPQ) shares plunged 4.79 percent to $18.28 in the post-market trading. The company swung to a third quarter net loss of $8.9 billion or $4.49 per share compared to a net profit of $1.9 billion or $0.93 per share in the same period last year. The adjusted net income was $2.0 billion or $1.00 per share, down from $2.3 billion or $1.10 per share last year. The revenue declined 5 percent to $29.67 and also missed the analysts’ estimate of $30.10 billion.

Big Lots Inc. (BIG) shares plunged 4.53 percent to $37.08 in the post-market trading. The stock has a 52-week low of $30.79, a 52-week high of $47.22 and $2.47 billion in market capitalization.

Whitestone REIT (WSR) shares fell 3.67 percent to $12.85 in the post-market trading. The company announced Wednesday that it intends to sell 4,000,000 of its common shares in an underwritten public offering.