was a French surgeon born in Russia who gained fame for his technique of grafting monkey testicle tissue on to the testicles of men while working in France in the 1920s and 1930s. This was one of the first medically accepted rejuvenation therapies (before he was proved to be wrong around 1930–1940). The technique brought him a great deal of money, although he was already independently wealthy. As his work fell out of favor, he went from being a highly respected surgeon to a subject of ridicule. By the early 1930s, over 500 men had been treated in France by his rejuvenation technique, and thousands more around the world, such as in a special clinic set up in Algiers. Noteworthy people who had the surgery included Harold McCormick, chairman of the board of International Harvester Company, and the aging premier of Turkey. Swiss doctor Paul Niehans, who was one of the fathers of cellular therapy, developed in 1931–1949 years the so-called Fresh cell therapy. Fresh cell therapy is mainly the use of live animal embryo organs cells which are injected into the patient with the purpose of achieving a revitalizing effect. These cells are generally extracted from sheep’s fetuses because in comparison to other animals, like pigs, rabbits and cows, sheep are clean animals and rarely contract diseases. Of course animal cells are not able to be included in human tissue, but they can secrete factors for rejuvenating. That's why this rejuvenation technology, despite the harsh criticism is practiced to this day. Rejuvenation technology and its effects on individuals and society have long been a subject of science fiction. The Misspent Youth and Commonwealth Saga by Peter F. Hamilton are among the most well known examples of this, dealing with the short- and long-term effects of a near perfect 80-year-old to 20-year-old body change with mind intact. The less perfect rejuvenation featured in the Mars trilogy by Kim Stanley Robinson results in long-term memory loss and sheer boredom that comes with extreme age. The post-mortal characters in the Revelation Space series have long-term or essentially infinite lifespans, and sheer boredom induces them to undertake activities of extreme risk. Modern developments Aging is the accumulation of damage to macromolecules, cells, tissues and organs in and on the body which, when it can no longer be tolerated by an organism, ultimately leads to its death. If any of that damage can be