Motor control infections

Question 0

Botulism

Answer 0

-anaerobic, endospore forming, gr+ bacilli
-endospores are ubuiquitous, found in soil and marine sediments
-8 serotypes; humans affected by A, B, & E
-food-borne, or transmitted through wounds
Path
-botulinum toxin- blocks release of Ach at presynaptic membrane=flaccid paralysis
Risk
-home canning
-infants (honey!)
Disease
-foodborne botulism
-wound bot
-infant bot
-adult intestinal toxemia bot
-Iatrogenic bot
Tx
-supportive
-botulinum antitoxin (horse)

Question 1

Poliomyelitis

Answer 1

-small, non-enveloped, +sense ssRNA
-3 serotypes
-replicates in cytoplasm
-humans only reservoir
-transmitted fecal-orally
Risk factors
-old, pregnant, strenuous excercise, tonsillectomy, IM injections
Path
-infects and destroys anterior horn cells
Diagnostic
-viral isolation and serologic testing
-nuc acid testing for wild or vaccine strain
Prevention
-IPV (us) or OVP vaccine
-improve sanitary conditions
Disease
-abortive poliomyelitis
-aseptic meningitis
-paralytic poliomyelitis
-post-polio syndrome
-most infections asymptomatic

Question 2

Tetanus

Answer 2

-anaerobic, endospore forming, gr+ bacilli
-endospores ubiquitous, found in soil w/ crap
-heat labile
-destroyed by intestinal proteases
-transmitted through wounds
Path
-tetanospasmin toxin- prevents release of GABA & glycine=spastic paralysis
Disease
-generalized tetanus (most common)
-neonatal tetanus
-local tetanus
-cephalic tetanus
Tx
-wound cleaning
-antibiotics
-TIG
-tetanus toxoid vaccination

Question 3

HIV

Answer 3

-retrovirus, enveloped, +sense ssRNA
-replicates in nuc
-transmitted through sex, congenital, transfusions, needles
-“window period”-lag time btw infection and detectable antibodies
Genes
-p24gag-codes capsid
-p17gag-codes matrix proteins
-gp41env & gp120env-codes envelope glycoproteins
-pol- codes for viral enzymes
-CCR5delta32 gene- mutation that provides immunity to HIV (r5 type?)
Virulence
-highly glycosylated envelope proteins
-proviral latency in microglial cells and resting T cells
-removes MC class I to avoid CTL killing
-decreases expression of HLA-A/B to avoid NK killing
-destroys CTLs and T helper cells
Path
-destruction of CD4+T cells
Disease
-acute infection
-chronic HIV
-AIDS
-long-term non-progressor
Tx
-antiretroviral therapy (HAART/ART)
Prevention
-safe sex
-screen donated blood
-treat STDs
-pre-exposure prophylaxis