Ketchum BSC Flashcards
Define synesthesia
Condition where one type of simulation evokes the sensation of another (i.e. sound produces color visualization)
Define paresthesia
Skin sensation such as burning, prickling…
What is kinesthesia?
What consequence with be suffered sensation wise dues to severing the ulnar nerve at the elbow?
Anesthesia
What effect does loss of innervation have on muscle cells?
Denervation Atrophy
What do you see with denervation? What do you not see?
See loss of size and angulation in myofibers, with loss of 80-90% of mass in weeks to months. In extreme atrophy, nearly all sarcoplasm is lost, with myofiber is reduced to a cluster of nuclei.
Do not see myonecrosis
What is the primary cause of myofilament degradation in denervation atrophy?
Increased proteosome activity, degredation of intracellular proteins. Loss of trophic factors lead to unmasking of degredation sequences.
What are the two steps of the ubiquitin-proteosome process?
If EMG is abnormal and NCS is normal what is the classification? what conditions can be ruled out?
Myopathy
Rule out: ALS, MS, WNV polio like syndrome
What happens in Myasthenia Gravis?
Anti-AChR is produced, blocking binding of ACh to AChR.
This also stimulates degredation of AChR on the muscle cell.
What are the two major clinical forms of MG?
Ocular MG - strictly ocular symptoms
General MG - Patient has generalized weakness
(85% of ocular MG patients progress to general within 2 years)
How is contraction connected to surrounding ECM?
Costamere
-Constitutive cytoplasmic/transmembrane protein complex
What is dystrophin?
Constitutive…
How does mutated dystrophin cause disease?
Cells expressing mutated dystrophin show increased Ca2+ flux leading to increased intracellular Ca2+ and increased oxidative stress.
Results in myofiber necrosis, myofibers replaced by CT and adipocytes.
