“increasing intracellular concentrations of either tyrosine or L-DOPA both result in an increase in melanogenesis” or formation of the black pigment melanin. Thus there appears to be an association between reduced L-DOPA production and white skin. As suggested by the Figure and information in this section, reduced L-DOPA, resulting in white skin, appears to be associated with an increased risk of macular degeneration for white individuals over the age of 80. Environment and lifestyle
Smoking: Smoking tobacco increases the risk of AMD by two to three times that of someone who has never smoked, and may be the most important modifiable factor in its prevention. A review of previous studies found "a strong association between current smoking and AMD. ... Cigarette smoking is likely to have toxic effects on the retina." Hypertension (high blood pressure): In the ALIENOR study 2013, early and late AMD were not significantly associated with systolic or diastolic blood pressure (BP), hypertension, or use of antihypertensive medications, but elevated pulse pressure [(PP) systolic BP minus diastolic BP] was significantly associated with an increased risk of late AMD. Atherosclerosis
High cholesterol: Elevated cholesterol may increase the risk of AMD
Obesity: Abdominal obesity is a risk factor, especially among men
Fat intake: Consuming high amounts of certain fats, including saturated fats, trans fats, and omega-6 fatty acids, likely contributes to AMD, while monounsaturated fats are potentially protective. In particular, omega-3 fatty acids may decrease the risk of AMD.
Cervical spinal nerve C7 controls triceps and wrist extension. Cervical spinal nerve C8 helps control the hand. The cervicocranial syndrome occurs when symptoms arise due to cervical vertebrae damage (misalignment, collapse, shift or disease, such as tumor) resulting in the improper functioning of the cervical spinal nerves. Examples of Cervicocranial Syndrome Pathophysiology
Chordoma
The craniocervical junction region comprises C1 (Atlas), C2 (Axis) and the lower part of the skull: occipital bone. In case of tumor: chordoma, in the craniocervical junction region, this leads to pressure on the cervical spinal nerves, which results in their improper functioning of the cervical spinal nerves. Hence, leading to symptoms of cervicocranial syndrome. To decompress the pressure on the nerves, the tumor is removed and the foramen through which the spinal nerve roots travel through is enlarged to allow the nerves to pass through so that symptoms of cervicocranial syndrome can be reduced and the nerves are sending signals. Atlanto-Occipital Assimilation
When the occipital bone and the atlas (C1) are fused together in a condition called atlanto-occipital assimilation, it causes improper functioning of the cervical spinal nerves due to the vascular compression. Surgical procedure can decompress the nerves and reduce symptoms. Trauma
Traumatic injuries are caused when external forces damage the cervical spine, giving rise to various symptoms. In a car accident, the vehicle jerks the neck forward and backward resulting in cervical spine damage resulting in a whiplash.