Tillett discovered streptokinase, later used for the acute treatment of myocardial infarction, at Bellevue in 1933. Nina Starr Braunwald performed the first mitral valve replacement in 1960 at the hospital. In 1967, Bellevue physicians perform the first cadaver kidney transplant. In 1971, the first active immunization for hepatitis B was developed by Bellevue physicians. Bellevue played a key role in the development of the "Triple Drug Cocktail" or HAART, a breakthrough in the treatment of AIDS, in 1996. In October 2014, Bellevue took in an Ebola patient, Craig Spencer, an individual who worked with Médecins Sans Frontières (Doctors Without Borders) in Guinea a month prior during the 2014 Ebola virus epidemic in West Africa. Facilities One of the largest hospitals in the United States by number of beds, it handles nearly 460,000 non-ER outpatient clinic visits, nearly 106,000 emergency visits and some 30,000 inpatients each year. More than 80 percent of Bellevue's patients come from the city's medically underserved populations. Bellevue is a safety net hospital, in that it will provide healthcare for individuals regardless of their insurance status or ability to pay. The hospital occupies a 25-story patient care facility with an ICU, digital radiology communication and an outpatient facility. The hospital has an attending physician staff of 1,200 and an in-house staff of about 5,500. Bellevue features separate pediatric (0-25) and adult (25+) emergency departments. In popular culture Bellevue has entered popular consciousness through its status as a major hospital in the largest city in the United States. The hospital notably treated the author Norman Mailer, who was taken to Bellevue after he stabbed his wife; and Mark David Chapman, who shuttled between Bellevue and the jail complex on Rikers Island after he shot and killed musician John Lennon. The poet Allen Ginsberg, also a former patient, mentioned the hospital by name in his famous poem "Howl" (1955). The hospital was mentioned or featured in the end of the music video of the Van Halen song "Hot for Teacher" in which lead guitarist Eddie Van Halen becomes a psychiatric hospital patient after he (fictionally) graduated from school. Bellevue is referenced by the character Amy in the 1970 Broadway musical Company by Stephen Sondheim. The character, experiencing cold feet on her wedding day, threatens to move into the "hopeless cases" section at the hospital. In 2000, rapper Wyclef Jean referenced Bellevue in the song "Where Fugees At?" on his