Write 6 page essay on the topic ALS.Physiology of ALS The central nervous system of the human body comprises of the brain and the spinal cord, while the nerves present all throughout the body e.g. in

Write 6 page essay on the topic ALS.

Physiology of ALS The central nervous system of the human body comprises of the brain and the spinal cord, while the nerves present all throughout the body e.g. in the arms, legs etc are known as the peripheral nervous system. Neurons are the basic components of a nervous system and those neurons that control voluntary muscles owing to chemical signals are known as motor neurons. In this disease the motor neurons of the body are targeted and degenerated gradually. Both upper body neurons and the lower body neurons are targeted. Since, the motor neuron control voluntary muscles, the muscles of the body are also affected. Pathogenesis of ALS It is believed that ALS is genetic in nature and occurs as a result of genetic mutations. The familial form of ALS is caused when the gene coding for the enzyme ALS1/SOD1 mutates while the sporadic form is caused when the gene coding for ALS2 mutates. “Mutations in SOD1 and its protein product initiate motor neuron disease through one or more toxic properties” (Pasinelli & Brown, 712-719). Several pathogenesis hypotheses have been proposed for this disease which includes oxidative stress, excitotoxicity, autoimmunity etc. The oxidative stress pathogenesis hypothesis is the key hypothesis which states that the mutant ASL1 enzyme catalyzes and enhances the production of hydroxyl radical, superoxide anions and other reactive oxygen species which damage the motor cells. Excitotoxicity is yet another valuable hypothesis which involves excitotoxicity of glutamate. Glutamate toxicity causes misbalance of calcium homeostasis inside the cells and increases the production of free radicals too leading to death of neurons. The hypothesis of autoimmunity phenomena on the other hand, is based upon the presence of autoimmunity present in sporadic ALS patients at the neuromuscular junctions of the brain as well as the spinal cord. Population Involved “ALS&nbsp.is&nbsp.found&nbsp.in&nbsp.people&nbsp.all&nbsp.over&nbsp.the&nbsp.world&nbsp.and&nbsp.has&nbsp.an&nbsp.incidence&nbsp.of&nbsp.about&nbsp.one&nbsp.per&nbsp.100,000&nbsp.of the&nbsp.population.&nbsp.At&nbsp.any&nbsp.given&nbsp.time,&nbsp.it&nbsp.is&nbsp.likely&nbsp.that&nbsp.about&nbsp.five&nbsp.people&nbsp.in&nbsp.100,000&nbsp.will&nbsp.be suffering&nbsp.from&nbsp.ALS” (Jacoby & Youngson,1257-1262) According to reports produced by the National institute of Neurological disorders and stroke almost 30,000 U.S. citizens have been diagnosed with ALS and the number increases each other by another 5000 new cases. People between the age brackets of 40-60 are more likely to develop the disease than others. Men are more vulnerable to disease than women. (National Institute of Neurological disorders & Stroke) Clinical presentation: Clinical features The symptoms of ALS appear in due course of time but are often mistaken for other neural diseases. The very first noticeable symptoms of the disease is the experience of weakness in certain areas especially in the bulbar, cervical, thoracic and lumbosacral regions of the body, which them slowly progresses to other parts.. The involvement of the bulbar region is crucial in proving the adverse effect on cranial nerves number IX, X, XI and XII which indirectly affects the muscles that these nerves innervate (tongue, larynx, pharynx and palate). Therefore with the onset of the symptoms in the bulbar region, the patient experience slurry speech, voice hoarseness and may choke during meals. The upper limb onset of the disease causes frequent cramping, stiffness and reduced working ability of the fingers. These