Skeletal system (Rubins) Flashcards
DMD
Severe prog X-linked , progressive degeneration of muscles
Most common death of DMD patients
Resp insufficiency due to cardiac arrhythmia and muscular weakness
DMD cause
Mutation of Dystrophin short arm of X xsome (Xp21)
Dystrophin function
Links sarcolemma the ECM
Dermatomyositis
Heliotropic rash on eyelids, elevated CK, inflammation of perimysium
MG
Serum antibodies directed against ACh receptors
MG Rx
Thymectomy
Polymyositis
Inflammation of endomysium, CD8+ T cells, anti Jo-1 antibodies, interstitial liver disease, nonerosive arthritis, Raynaud phenomenon
Lambert-Eaton myasthenic syndrome
Serum IgG bodies against calcium channels
Myotonic dystrophy
Fixed muscular movements, ptosis, fixed facial expression, slowing muscle relaxation, progressive muscle weakness and wasting
Carnityl palmityl transferase deficiency
Inability to transport long-chain fatty acids into the mitochondria
Carnityl palmityl transferase deficiency symptoms
Muscular pain after prolonged exercise+ Myoglobinuria
Pompe disease
3-month-old boy presents with severe hypotonia and areflexia. His tongue and heart are enlarged. A muscle biopsy displays massive accumulation of membrane-bound glycogen and disappearance of the myofilaments and other sarcoplas- mic organelles. The patient dies after 1 year.
Hurler syndrome
Mucopolysaccharide metabolism defect
Inclusion body myositis
The pathologic features of inclusion body myositis resemble those of poly- myositis and consist of single-fiber necrosis and regeneration with predominantly endomysial cytotoxic T cells. The inclusions are stained by Congo red and represent a form of intracellular amyloid that can be demonstrated by electron microscopy. The fibers in the electron micrograph shown here represent amyloid filaments. These filaments are immunoreactive for b-amyloid protein—same type of amyloid present in the senile plaques of Alzheimer disease. The pathogenic significance of these inclusions is not understood.
Rhabdomyolyssi
Degeneration of the skeletal muscle and release of myoglobin
Rhabdomyolysis complications
Acute renal failure and myoglobinuria
What are type II muscle fibers suitable for?
Rapid contractions of brief duration and react to strength training with hypertrophy.
Type II hypertrophy
Type II muscle fibers are suitable for rapid contractions of brief duration and react to strength training with hypertrophy. Androgenic steroids also induce hypertrophy of type II fibers, and disuse of the mus- cle results in their selective atrophy. Skeletal muscle does not respond to an increased workload by increasing the number of fibers (hyperplasia).
Achondroplasia
Fibroblast Growth Factor
Blue sclerae
Osteogenesis Imperfecta
Osteogenesis Imperfecta
Mutations of COL1A1 and COL1A2 genes, which encode the a1 and a2 chains of type I procollagen, the major structural protein of bone.
Lysyl hydroxylase
Ehlers Danlos
Fibrillin gene mutation
Marfan’s syndrome
High androgen levels lead to
Premature closure of epiphyseal plates and stunted growth
