Shares of United Natural Foods ( UNFI - Get Report) were among the Nasdaq's losers Wednesday, falling 6% after the organic food distributor posted mixed fourth-quarter results and gave a lower-than-expected sales forecast for fiscal 2007.

For the period ended July 31, the company earned $12.7 million, or 30 cents a share, on sales of $619.8 million. Analysts polled by Thomson First Call expected earnings of 30 cents a share and sales of $630.5 million. During the year-earlier period, the company earned $11.8 million, or 28 cents a share, on sales of $543 million.

Looking ahead, United Natural Foods forecast 2007 earnings of $1.25 to $1.30 a share and sales of $2.7 billion to $2.8 billion. Analysts project earnings of $1.29 a share, with sales of $2.82 billion. Shares were trading down $1.88 to $29.53.

DSW ( DSW) rose 2% after the shoe-store operator posted second-quarter earnings that topped forecasts, though sales were below expectations. For the quarter ended July 29, the company earned $15.3 million, or 35 cents a share, up from $9.3 million, or 28 cents a share, a year earlier. Sales rose to $301.3 million from $276.2 million, while same-store sales increased 2.2%. Analysts anticipated earnings of 30 cents a share, with sales of $308 million.

DSW continues to project 2006 earnings of $1.24 to $1.27 a share. Analysts predict earnings of $1.25 a share. The stock was up 66 cents to $28.76.

Shares of Layne Christensen ( LAYN) rose 4% after the water and wastewater services company posted better-than-expected second-quarter results. The company earned $7.2 million, 47 cents a share, on revenue of $187.1 million. Wall Street expected earnings of 38 cents a share on revenue of $168.3 million. A year earlier, Layne Christensen earned $4.5 million, or 35 cents a share, on revenue of $106.1 million.

"The second quarter will likely be our peak this year as it was last year, but all our business units continue to be extremely busy," the company said. "The housing market, rising interest rates and the leveling off of precious and base metal pricing will eventually have some impact on activity, but at this stage the effect is not discernable." Shares were trading up $1.27 to $33.03.

Costco ( COST - Get Report) fell 4% after the warehouse club operator warned that fourth-quarter and full-year earnings will miss Wall Street's expectation. For the fourth quarter ending Sept. 3, the company expects earnings of 68 cents to 71 cents a share. Analysts project earnings of 77 cents a share. For the full year, the company projects earnings of $2.23 to $2.26 a share, below expectations of $2.33 a share. Costco's estimates include a one-time income tax charge of about 3 cents a share.

"The principal factor leading to our revised fourth-quarter earnings outlook is lower-than-planned gross margins," the company said. In May, Costco said that analysts' estimates of 77 cents a share for the fourth quarter and $2.33 a share for the full year were at the high end of the company's forecast. Shares were down $1.80 to $47.45.

Shares of Public Service Enterprise Group ( PEG - Get Report) fell 4% after the company said that its merger deal with Exelon ( EXC - Get Report) is in jeopardy. "Although Exelon remains committed to its ongoing efforts to complete the merger, Exelon management determined that the probability of completion of the merger is no longer 'more likely than not' based on the status of settlement discussions in the proceedings before the New Jersey Board of Public Utilities," Public Service Enterprise said in a Securities and Exchange Commission filing. Exelon offered to buy Public Service in December 2004 for about $18 billion. Shares of Public Service Enterprise were trading down $3.15 to $67.75, while shares of Exelon fell 12 cents to $60.18.

NYSE volume leaders included Ford ( F - Get Report), unchanged at $8.26; Lucent Technologies up 7 cents to $2.37; Pfizer ( PFE), up 19 cents to $27.79; Sprint Nextel ( S), up 14 cents to $16.86; Exxon Mobil ( XOM), down 64 cents to $68.77; Advanced Micro Devices ( AMD), up 10 cents to $24.50; Motorola , up 30 cents to $23.74; and General Electric ( GE), up 6 cents to $34.25.

Nasdaq volume leaders included Intel ( INTC), down 4 cents to $19.64; Sun Microsystems ( SUNW), up 4 cents to $5.03; Apple Computer ( AAPL), up $1.18 to $67.66; Cisco Systems ( CSCO), down 9 cents to $21.59; Novell , down 9 cents to $6.69; and Microsoft ( MSFT), down 7 cents to $25.77.