Artificial heart was named after its manager. Graduate student Robert Jarvik was the project manager for the artificial heart, which was subsequently renamed the Jarvik 7. In 1981, William DeVries submitted a request to the FDA for permission to implant the Jarvik 7 into a human being. On December 2, 1982, Kolff implanted the Jarvik 7 artificial heart into Barney Clark, a dentist from Seattle who was suffering from severe congestive heart failure. Clark lived for 112 days tethered to an external pneumatic compressor, a device weighing some , but during that time he suffered prolonged periods of confusion and a number
Human artificial chromosome by these vectors not only leads to different expression levels, but the inserts also disrupt the original genome. HACs differ in this regard, as they are entirely separate chromosomes. This separation from existing genetic material assumes that no insertional mutants would arise. This stability and accuracy makes HACs preferable to other methods such as viral vectors, YACs and BACs. HACs allow for delivery of more DNA (including promoters and copy-number variation) than is possible with viral vectors. Yeast artificial chromosomes and bacterial artificial chromosomes were created before human artificial chromosomes, which first appeared in 1997. HACs are useful in expression