More than 750 plaintiffs sued the Johns Hopkins Hospital System on Wednesday over medical experiments in Guatemala in the 1940s and 1950s during which subjects were infected with venereal diseases. The lawsuit in Baltimore seeks $1 billion for individuals, spouses and children of people infected with syphilis, gonorrhea and other sexually transmitted diseases through a United States government program. The suit claims Johns Hopkins officials had "substantial influence" over the studies, controlling some advisory panels, and were involved in planning and authorizing experiments. A Hopkins lawyer called the suit, the latest over the studies, baseless. A federal judge in 2012 dismissed a lawsuit against the government over the same study.