• Arrowhead Research (Pasadena, California) reported the addition of three executives to its management team: Thomas Haag, PhD, chief patent officer; Mark Tilley, PhD, VP of advanced materials; and James Hamilton, MD, VP of medical technologies. Tilley previously was senior investment manager at DSM. Haag was with the Washington offices of Kenyon & Kenyon and McDermott Will & Emery. Hamilton is a cofounder of NanoValent Pharmaceuticals. Arrowhead Research is a nanotechnology company.

• Robert Gontarek was named COO of Diagnostic Health (DHC; Birmingham, Alabama), effective Monday, May 19, 2008. Gontarek most recently was executive VP of operations for CBIZ Medical Management Professionals. DHC is an independent provider of diagnostic imaging services.

• Bernie O'Rourke was named executive VP/COO of InSight Health Services Holdings Corp. (Lake Forest, California). O'Rourke has been senior VP/GM, Eastern Division of InSight since March 2006. InSight is a provider of diagnostic imaging services.

• Leerink Swann (Boston) has named Stephen Weiss as senior managing director, head of institutional equities, and promoted John Sullivan to the role of director of research. Weiss was previously co-head of institutional sales and a senior managing director for Leerink Swann. Sullivan joined Leerink Swann in 2004 as an equity research analyst in the life sciences tools and consumables sector. Leerink Swann is a healthcare-focused investment banking firm.