From the European aristocrats in ancient times to the American rich in modern society, there have been many people who regard blood plasma as the “fountain of youth”. Blood obsessives believe that by continually ingesting the blood of young people, the dying old can be rejuvenated. 　　It’s a real-life “Vampire Diaries” story that’s been in the news recently. On May 23, local time in the United States, in order to prove the existence of “rejuvenation”, Brian Johnson, a super rich man in Silicon Valley and a technology entrepreneur, used his own body, the body of his 17-year-old son Tallmadge and his 70-year-old father Richard De’s body, together with three generations…