The rating on Merrill Lynch Puttable FLOATs/RITES Trust puttable floating option tax-exempt receipts PT-577, relating to New Jersey Health Care Facilities Financing Authority revenue bonds medical center issue series 2001, has been affirmed following an amendment to the trust documents. The long-term component of the rating is based on the Ambac-insured underlying bond. The short-term component of the rating is based on a liquidity facility from Svenska Handelsbanken. The expiration date of the liquidity facility is July 15, 2006. The stable outlook is based on the outlook of the bond insurer.