By Matt Audilet Russian 400-meter hurdler Natalya Antyukh is being stripped of her gold medal from the 2012 London Olympic Games. The Athletics Integrity Unit found Antyukh guilty of doping between July 2012 and June 2013. Antyukh did not appeal the AIU decision that saw all results from that time period wiped away. The AIU said the IOC could now “proceed with the reallocation of medals and the update of the IOC database,” per CBS News. This penalty puts former American track and field athlete Lashinda Demus in position to take the gold medal from that 2012 event. Zuzana Hejnová of the Czech R…