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Flashcards in Bacterial Neurotoxins Deck (27)
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0
Q

What causes botulism, tetanus, and gas gangrene?

A

Clostridia

1
Q

Clostridia- catalase, anaerobes, gram

+or -?

A

Gram +
Catalase -
Strict Anaerobic

2
Q

Why can’t Clostridia break down h2o2?

A

They are catalase -

3
Q

What happens when Clostridia is in presence of 02?

A

Toxic superoxide anions accumulate– they lack the enzyme superoxide dismutase
And are strict anaerobes

4
Q

Can clostridium use oxygen as final e acceptor?

A

NO

5
Q

Paralytic illness die to neurotoxins made by c botulinum

A

Botulism

Food
Wound
Infant floppy baby syndrome

6
Q

Which type of botulism has preformed toxin and which is the toxin made in vivo?

A

Infant made in vivo and food poisoning is preformed toxin

7
Q

Most common botulinum toxin forms

A

A b and e

8
Q

Can c botulinum be killed w heat?

A

Spores are heat resistant

9
Q

Mode of action for c botulinum?

A

Interferes w release of ach at neuromuscular junction results in flaccid paralysis

10
Q

BoNT

A

C botulinum

11
Q

C botulinum is what kind of enzyme?

A

BoNT is a endoprotease

12
Q

How does c botulinum interrupt nmj?

A

The neurotoxin cleaves a price of neuro secretory apparatus like a membrane protein (snare proteins) so seiches can’t release ach

13
Q

How does good poisoning develop?

A

C botulinum spores contaminate canned or packed food and germinate in the alkaline pH!
Anaerobic conditions allow vegetative form and toxin is produced
Absorbed by body and toxin is NOT killed by digestive enzymes

14
Q

Clinical manifestations of food botulism?

A

Dry mouth, hard to swallow, visual disturbances, speech issues, descending paralysis
But NO FEVER
recovered people don’t have antitoxin in blood

15
Q

Floppy baby syndrome

A

Gi Tract colonized from env source (honey?) and toxin produced in vivo
Treatment is BIG-iv - intravenous botulism immune globin –human derived antitoxin antibodies

16
Q

Deadliest toxin with no known antidote

A

Botulinum toxin type H

17
Q

Good uses of Botox

A
Muscle spasms
Migraines
Over active bladders
Strabismus
Cosmetic use
18
Q

Neurotoxin of tetanus

A

Tetanospasmin

19
Q

What makes Tetanospasmin?

A

Clostridium tetani

20
Q

Spores of c tetani is found in

A

Feces and soil

21
Q

Clinical symptoms of tetanus

A
Trismus (lockjaw)
Risus sardonicus(sustained grin)
Stiff neck 
Hard to swallow, rigid abdominals
Voluntary muscle spasm
22
Q

C tetani mode of action

A
Cleaves VAMP(synaptobrevin)
And prevents release of neurotransmitter glycine from inhibitory intereurons in spinal cord
Leads to stimulation of muscle contractions
23
Q

How does tetanus get in body?

A

Puncture wounds or burns

24
Q

Inside body what happens with c tetani

A

Spores get in through wound and reverts to vegetative form w help from organisms and necrotic tissue
Toxin spreads in blood and lymph associated w nerves
Toxin combines with gangliosides

25
Q

Treatment for tetanus?

A

Antitoxin- doesn’t neutralize toxin already bound to nerve tissue

Immunization
Prevention - TETANUS IMMUNE GLOBIN(tig)

26
Q

What does metronidazole do

A

Inhibits c tetani growth