Ob Peds
Autor: Jennygtrujillo • September 15, 2015 • Coursework • 341 Words (2 Pages) • 775 Views
​Muscular dystrophies are genetic disorders that produce progressive degeneration and necrosis of skeletal muscle fibers and eventual replace areas with connective tissues and fat. This results in necrosis of the muscle and causes muscle weakness. Two commons types of muscular dystrophies ( Duchene muscular dystrophy (DMD) and Becker muscular dystrophy (BMD)) are inherited as a X-linked recessive trait, missing segment of DNA (McCance, Huether, Brashers, & Rote, 2010), or can be caused by mutations in the dystrophin gene, which is located on the short arm of the X chromosome (Twee T Do, 2014). DMD is more rapid with onset around 3 years of age and muscle anchors tear apart, while BMD is milder with onset around 5 to 15 years of age. In DMD, BMD, and FMD weakness and muscle wasting occur in neck and shoulders and continue down to the pelvic girdle area (McCance, Huether, Brashers, & Rote, 2010). Dystrophin is a bulky protein that is in a variation of tissue and it is found in muscle cells. It attaches portions of the sarcomere to the cell membrane to maintain the structural integrity of the skeletal and cardiac muscles (Twee T Do, 2014). Defects or changes in dystrophin show muscle cell degeneration and muscle biopsies in patients of DMD show little or no dystrophin, although patients with BMD have mutations in the dystrophin gene. Muscle chemistry of muscular dystrophy occurs in the neuromuscular junction. Acetylcholine (ACh) is released from the motor neurons in the myoneural junction then crosses the synaptic space to reach receptors that are concentrated in the folds of the endplate of the muscle fiber. Once released, ACh is rapidly broken down by the enzyme acetylcholinesterase (AChesterase). Facioscapulohumeral muscular dystrophy (FMD) is an autosomal dominant trait with defect in the 4q35 locus (Twee T Do, 2014) which onset occurs in childhood to adulthood and with a moderate rate of progression (McCance, Huether, Brashers, & Rote, 2010). Limb
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