At the left, an H&E stain demonstrates a rounded pink cytoplasmic Lewy body in a neuron of the cerebral cortex from a patient with diffuse Lewy body disease, which can be a cause for dementia. Lewy bodies can also be seen in substantia nigra with Parkinson's disease. An immunohistochemical stain for ubiquitin, seen at the right, helps demonstrate the Lewy bodies more readily by the brown reaction product within them.