Prions Flashcards
______ _______ are rare, fatal, rapidly progressive neurodegenerative diseases that occur in humans and other animal species.
possess small vacuoles within the neuropil, which produces a spongiform appearance
Prion Diseases
The complex net of axonal, dendritic, and glial branchings that forms the bulk of the central nervous system gray matter of the brain and in which the nerve cell bodies are embedded
Neuropil
Bovine spongiform encephalopathy affects ______.
Scrapie affects ____ ___ _____
cattle
sheep and goats
Kuru
Creutzfeldt-Jakob disease (CJD)
Variant Creutzfeldt-Jakob disease (Variant CJD)
Gerstmann-Sträussler-Scheinker syndrome (GSS)
Fatal familial insomnia (FFI)
Human Prion Diseases
fatal neurodegenerative disease of sheep
demonstrated to be a transmissible disorder
Scrapie
fatal neurodegenerative disease of humans recognized since the 1920s
demonstrated to be transmissible in the 1960s (humans to chimpanzees)
Early symptoms: memory problems, behavioral changes, poor coordination, and visual
disturbances
Later symptoms: dementia, involuntary movements, blindness, weakness, and coma 70% of people die within 1 year of diagnosis
Creutzfeldt-Jakob disease (CJD)
A prion is a ______ and ______ particles
Proteinaceous
infectious
PRNP gene on chromosome 20 encodes ___ _______.
PrP protein
Met or Val at codon 129 of PRNP gene
60% Met codon; 40% Val codon homozygote for either = increased risk of disease
a PrP polymorphism
t/f: PrPSc is resistant to degradation and accumulates in amyloid fibrils
true
t/f: PrPC is strongly expressed in both neurons and glial cells of the CNS and appears to regulate ion channels and neurotransmitter receptors at the pre- and postsynaptic levels.
true
Median Age of Death: 68 years
Median duration of illness: 4-5 months
Clinical signs and symptoms: dementia, early neurologic signs
CJD
Median Age of Death: 28 years
Median duration of illness: 13-14months
Clinical signs and symptoms: prominent psychiatric/behavioral symptoms; painful dysthesias; delayed neurologic signs
Variant CJD
t/f: Prions may not be inactivated by means of routine surgical instrument sterilization procedures.
true
t/f The World health Organization and the US Centers for Disease Control and Prevention recommend that instrumentation used in such cases be immediately destroyed after use.
true
