Endotoxins and Endotoxins (4star!!)

Question 1

what produces endotoxins

Answer 1

gram (–) bacteria–> are a part of outer membrans and are released when the bacteria lyse

Question 2

what three things in body do endotoxins activate

Answer 2

1. macrophages
2. complement
3. tissue factor

Question 3

what three cytokines do activated macrophages produce and their effect

Answer 3

1. IL-1 = fever
2. TNF = fever, hypotension
3. NO = hypotension

Question 4

What two complements are activated by endotoxin and effects

Answer 4

1. C3a = hypotension, edema

2. C5b = neutrophil chemotaxis

Question 5

What does activated tissue factor do and what complication can ensue

Answer 5

activates coagulation cascade –> can result in DIC

Question 6

what kind of bacteria make exotoxin

Answer 6

gram + –> is a preformed toxin

Question 7

how do superantigens work

Answer 7

bind simultaneously to MHC II and TCRs to stimulate many T-cells = MASSIVE cytokine release

Question 8

3 symptoms of toxic shock syndrome

Answer 8

1. high fever
2. hypotension
3. diffuse rash

Question 9

what 8 toxins are secreted by Staph aureus

Answer 9

1. α toxin–> hemolysis
2. β toxin–> sphingomyelinase
3. γ toxin–> A+B sub = hemolysin; B+C= leukocidin
4. hemolysin
5. Leukocidin
6. Enterotoxins A-E–> vomiting and diarrhea
7. TSST-1–> toxic shock syndrome
8. Epidermolytic/ exfoliative toxin –> scalded skin syndrome

Question 10

what two bacteria can cause toxic shock syndrome

Answer 10

1. Staph aureus

2. group A strep (s. pyogenes)

Question 11

What three toxins does S. pyogenes secrete?

Answer 11

1. Streptolysin O–> hemolysis
2. Streptolysin S–> hemolysis
3. Erythrogenic/ pyrogenic toxins

Question 12

which strep pyogenes toxin is used to test for strep and the one responsible for hemolysis on blod agar plate

Answer 12

Streptolysin O –> is oxygen labile

Question 13

which strep toxin is responsible for scarlet fever

Answer 13

pyrogenic/ erythrogenic toxins

Question 14

toxin inactivates EF-2 , causes pseudomembranes (how does it inactivate?)

Answer 14

Diptheria toxin–> via ADP ribosylation

Question 15

toxin other than diptheria that acts at EF-2

Answer 15

exotoxin A of pseudomonas

Question 16

cleaves host cell rRNA in 60s subunit at adenosine (2 toxins)

Answer 16

1. Shiga toxin

2. veracytotoxin (Shiga-like toxin)–> made by 0157:H7 E.coli

Question 17

what complication can 0157:H7 E. coli cause

Answer 17

hemolytic uremic syndrome (HUS)

Question 18

symptoms of HUS

Answer 18

1. hemolytic anemia
2. thrombocytopenia
3. acute renal failure

Question 19

2 toxins produced by ETEC, what do they do

Answer 19

1. heat labile toxin–> ↑ cAMP = Cl- and H20 secretion

2. heat stabile toxin–> ↑ cGMP = less Na and water reabsorption

Question 20

ETEC causes

Answer 20

travelers diarrhea

Question 21

organism causing pseudoappendicitis

Answer 21

Yersinia enterocolitis

Question 22

Yersinia toxin MOA

Answer 22

increases cGMP

Question 23

edema factor, lethal factor, protective antigen; how does edema factor work

Answer 23

Bacillus anthracis–> increases cAMP

Question 24

cholera toxin MOA

Answer 24

binds irreversibly to Gs subunit–> cAMP increases

Question 25

pertussis toxin MOA

Answer 25

binds to and inactivates Gi–> cAMP increases, no way to turn it off

Question 26

blocks release of GABA and glycine

Answer 26

tetanospasmin (tetanus toxin)–> spastic paralysis

Question 27

flaccid paralysis–> how and what organism

Answer 27

botulism toxin (exotoxins A-G)–> inhibit release of ACh

*babies get from honey; people from canned foods w/ preformed toxin

Question 28

what two toxins does C. perfringens have; how they work

Answer 28

1. α-toxin –> is a phospholipase, causes gas gangrene and myonecrosis
2. enterotoxin–> food poisoning, produced in food that is left out after cooking (spores grow that have survived cooking process)