Frederick Banting in the blood which was then excreted in urine. Attempts to extract insulin from ground-up pancreas cells were unsuccessful, likely because of the destruction of the insulin by the proteolysis enzyme of the pancreas. The challenge was to find a way to extract insulin from the pancreas prior to its being destroyed. Moses Barron published an article in 1920 which described experimental closure of the pancreatic duct by ligature; this further influenced Banting's thinking. The procedure caused deterioration of the cells of the pancreas that secrete trypsin which breaks down insulin, but it left the islets of Langerhans intact. Banting
Frederick Banting eyesight. Banting successfully joined the army in 1915 and spent the summer training before returning to school. His class was fast-tracked to get more doctors into the war and so he graduated in December 1916 and reported for military duty the next day. He was wounded at the Battle of Cambrai in 1918. Despite his injuries, he helped other wounded men for sixteen hours, until another doctor told him to stop. He was awarded the Military Cross in 1919, for heroism. Banting returned to Canada after the war and went to Toronto to complete his surgical training. He studied orthopedic