At least four top executives at Marvel Entertainment Group, including president and chief executive officer David Schreff, have been pinkslipped as part of the company’s ongoing efforts to cut costs and emerge from Chapter 11 bankruptcy.In addition to Schreff, other senior managers who got the ax Aug. 15 were Ken Lewis, executive VP of strategic alliances, and Sandra Padnos, exec VP of communications. On Tuesday, Marvel reported a second-quarter loss of $41.9 million, compared with a loss of $11 million in the same period last year. “The dismissals are part of a continuing effort to streamline the operation and reduce significant overhead costs,” a company spokesman said Tuesday. The Marvel management team sent packing last week was assembled just about a year ago, when Marvel was controlled by billionaire financier Ronald Perelman. In June, Perelman lost control of the company when a bankruptcy judge ruled against him in a prolonged legal battle with Marvel bondholders led by investor Carl Icahn. Icahn has since taken over and is rumored to be shopping for a buyer for the comic book giant. A bankruptcy court hearing scheduled for today in Delaware is expected to shed more light on Marvel’s uncertain future.