diseases of the week Flashcards
in cystic fibrosis, a mutation in a gene changes a protein that regulates the movement of ___ in and out of the cell
salt
cystic fibrosis is caused by a mutation to a gene that changes a protein…what does the gene code for
the gene codes for Cl- ion channel, so normal Cl transport across cell membranes does not occur
in CF, the mutated Cl- channel may also affect what?
can have an influence on neighboring Na+ channels, disrupting normal sodium transport
- b/c water movement follows ion movement via osmosis, if ion movement is disrupted, normal water transport across membranes will also not occur (water movement necessary to keep mucus thin & flowing)
in CF, the Cl- channel is called ___
CFTR (cystic fibrosis transmembrane regulator)
normal CFTR channel: moves chloride ions to the outside of the cell
mutant CFTR channel: does not move Cl- ions, causing sticky mucus to build up on outside of cell
most common organs affected by CF
lungs and pancreas
multiple sclerosis aka ___
quantitative demyelination
what is MS?
autoimmune disease, immune system attacks and begins to destroy the myelin that wraps nerve axons in the CNS –> nerves can become damaged with resultant accumulation of scar tissue, as myelin is lost, AP conduction becomes less efficient, AP velocity much slowed and maybe blocked
disease progresses in waves, as it advances, brain has more difficulty sending signals correctly through NS
advanced stages- nerves damaged/destroyed
why do AP’s slow down in MS?
voltage gated Na+ channels in nodes of ranvier in myelinated axons, fewer channels in membrane that are insulated by myelin
AP velocity in naked axons of humans will be slow because small diameter
symptoms of MS
fatigue
difficult to concentrate and walk
muscle weakness/pain
blurred vision
depression
correlation between what diseases and MS (cause and effect)
measles, herpes, Epstein-Barr
what is known to reduce symptoms of MS
vitamin D
what drug helps fight MS
teriflunomide (Aubagio), immunosuppressant drug works by inhibiting main enzyme and blocking pyrimidine synthesis
- also gilenya- delays accumulation of physical disability
