Leaders at Carney Hospital in Boston are seeking up to $30 million in funding to keep the facility running as an acute-care hospital. Caritas Christi Health Care chief executive Ralph de la Torre has pitched a plan to invest in the run-down hospital, bring new doctors to the facility, and revitalize Laboure College, the nursing school that is part of the Carney campus. He is seeking $20 million to $30 million from outside sources, including funds from the city, state, foundations, and individuals.