Chapter 27: muscles Flashcards
muscle cells
- ______, terminally differentiated cells that cannot divide
- specialized cells that are rich in ______ (actin and myosin)
- primary function: ______
- high ratio of ______ to ______
- ______ and extensible cells
- nuclei located ______ the cell membrane
postmitotic contractile proteins contractibility cytoplasm nuclei long beneath
- the site of contact between the axon and the muscle fiber
- ______- neurotransmitter
- enzyme ______
neuromuscular junction (NMJ)
acetylcholine
cholinesterase
normal muscle and muscle diseases
- many ______ and ______ may affect the muscle
- muscle is often affected by ______ disorders
- destruction of ______ is characterized by a release of ______
- muscle cells are relatively resistant to ______
toxin drugs autoimmune muscle fibers creatine kinase (CK) infections
inflammatory disorder of the skin and skeletal muscle. idiopathic cause. rash of the ______ (heliotrope rash). red papules on the elbows, knuckles, and knees (______ lesion)
- lab findings: increased ______ ______ and ______ antibody.
- treatment: ______
dermatomyositis upper eyelids grotton creatine kinase anti-jo-1 corticosteroid
inflammatory disorder of skeletal muscle. similar to dermatomyositis clinically, but ______ is not involved; proximal muscle weakness, ______ inflammation (CD8+ T cells) with ______ muscle fibers is seen on biopsy
-treatment: ______
polmysositis skin endomysial necrotic corticosteroids
- form of muscle cell atrophy caused by injury of the nerves
- upper motor neuron ______
- lower motor neuron- ______
neurogenic atrophy
central cortex
spinal cord
soft tissue injuries
- muscles
- beneath skin layers
- ______: thick, fibrous inflexible membrane surrounding muscle that aids in binding muscle groups together
soft-tissue injuries
fascia
- ______: natural patterns in the surface of the skin revealing tension within
- ______: topographical region of body surface innervated by one nerve root
tension lines
dermatones
- it is the dissolution of skeletal muscle fibers and release of ______ into the circulation, which may result in myoglobin in the ______ and acute ______ failure. may be acute, sub acute, or chronic. during acute, muscles are ______, ______ and profoundly weak
- causative factors: influenza, ______ etc. pain to rhabdomyolysis, is also well known during treatment with cholesterol-lowering agents (______)
- pathological features: ______ of muscle fibers and varying degrees of ______. clusters of ______ are seen in and around muscle fibers, but these are not accompanied by ______ or ______ cells
rhabdomyolysis myoglobin urine renal swollen tender statins necrosis degeneration macrophages lymphocytes inflammatory
myasthenia gravis: pathogenesis and treatment
- autoantibodies against ______
- hypersensitivity-______
- antibodies will block the ______ due to its binding to the receptor and resulting in no muscle movement
- antibodies are mostly synthesized by the ______ gland
treatment: - long lasting ______ to prevent the breakdown of acetylcholine @ ______
- ______ to remove auto antibodies
- ______ drugs like cyclosporine-A
- surgery of the ______ in young patients
- diagnosis: ______ test and presence of ______ in blood
acetylcholine receptors II neuron transmission thymus anti-cholinesterase neuromuscular junction (NMJ) blood transfusion immunosuppressive thymus gland tensilon autoantibodies
______ and ______ are recognized in myasthenic patients
thymic hyperplasia
thymomas
myasthenia gravis: clinical symptoms
- ______ weakness and small ______ muscles and facial muscles most often involved
- ______, easy fatiguability on reading, facial muscle weakness, inability to ______, all muscles may become affected
muscular
extraocular
ptosis
chew
- antibodies against presynaptic calcium channels of the neuromuscular junction. known as ______ syndrome due to small cell carcinoma of the ______. leads to impaired ______ release
- firing of ______ calcium channels is required for acetylcholine release. may be ______. clinical features include proximal uscle weakness (______ and ______)
- treatment: treating the ______
lambert-eaton syndrome para-neoplastic lung acetylcholine presynaptic autoimmune limbs trunk cancer
- genetic defects inherited as mendelian traits. inherited as autosomal (dominant or recessive) or sex-linked traits
- a progressive course and symptoms related to muscle ______
- clinically, muscular dystrophies are a ______ group of diseases
- they differ from one another with regard to: mode of inheritance, age of onset, muscle groups that are initially affected and severity of the disease
- limited diagnostic value of histologic examination of muscle biopsy
- elevated ______ in the ______
muscular dystrophies wasting heterogenous CK blood
-most common muscular dystrophy
-caused by deficiency of dystrophin
-______ holds together other structural proteins, linking them to the cell ______
-degeneration of ______ cells with ensuing muscle ______
-______ recessive disease
-occurs only in ______
milder form-______: due to the mutated ______. better prognosis. death around ______
-clinical symptoms
-the abnormal muscle cells have an ______ shape, ______ of cytoplasm, and ______ located nuclei. calf ______ (replacement of muscle with fibrous and fatty tissue), presence of ______ (use of arms to rise from crouching position). difficulty getting up from a squatting position.
-appearance of symptoms in preschool children
-weakness of the weight-carrying muscles of the ______ girdle and ______ extremities. deformed legs, inability to keep legs ______, ______ and deformities of the extremities
-______ infections, ______ failure
-______ death- usually in the late teens or early 20s
duchenne-type muscular dystrophy dystrophin membrane skeletal muscle weakness sex-linked boys becker's dystrophy dystrophin 40 abnormal granularity centrally pseudohypertrophy gowers maneuver pelvic lower straight contractures pulmonary heart early
