Mitochondrial disease leading to neurodegeneration is likely, at least on some level, to involve all of these functions.There is strong evidence that mitochondrial dysfunction and oxidative stress play a causal role in neurodegenerative disease pathogenesis, including in four of the more well known diseases Alzheimers, Parkinsons, Huntingtons, and amyotrophic lateral sclerosis.Neurons are particularly vulnerable to oxidative damage due to their strong metabolic activity associated with high transcription levels, high oxygen consumption, and weak antioxidant defense. DNA damage
The brain metabolizes as much as a fifth of consumed oxygen, and reactive oxygen species produced by oxidative metabolism are a major source of DNA damage in the brain. Damage to a cells DNA is particularly harmful because DNA is the blueprint for protein production and unlike other molecules it cannot simply be replaced by re-synthesis. The vulnerability of post-mitotic neurons to DNA damage (such as oxidative lesions or certain types of DNA strand breaks), coupled with a gradual decline in the activities of repair mechanisms, could lead to accumulation of DNA damage with age and contribute to brain aging and neurodegeneration. DNA single-strand breaks are common and are associated with the neurodegenerative disease ataxia-oculomotor apraxia. Increased oxidative DNA damage in the brain is associated with Alzheimers disease and Parkinsons disease. Defective DNA repair has been linked to neurodegenerative disorders such as Alzheimers disease, amyotrophic lateral sclerosis, ataxia telangiectasia, Cockayne syndrome, Parkinsons disease and xeroderma pigmentosum. Axonal transport
Axonal swelling, and axonal spheroids have been observed in many different neurodegenerative diseases.
Sinusoidal hemangioma is a condition, by something of a misnomer, a term for a lesion that is a vascular malformation with various clinical presentations. This condition may present as nodules, often in the breast area or extremities, or as large firm bulging facial masses beneath normal-appearing skin; the latter have an aggressive and invasive course. See also
Sinus pericranii
List of cutaneous conditions


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