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
Highest and best use a series of tests. The exact definition of highest and best use varies, but generally the use must be the following: Only those uses that are, or may be, legally permitted are potential highest and best uses. This may exclude uses that are not, and unlikely to become, permitted by zoning, land use planning, uses forbidden by government regulations, and uses prohibited by deed restrictions or covenants. Properties with a use that predates existing zoning or other property regulations may be "legally nonconforming". Such "grandfathered uses" are generally legal even though they do not meet current zoning or other regulations.