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Flashcards in Helicobacter Deck (44):
1

Helicobacter disease is gram _____

negative

2

Helicobacter is ____ shape

Helical shaped

3

Helicobacter disease is found where?

found in the stomach

4

Helicobacter disease is what type of bacterium?

gram negative miicro-aerophilic bacterium

5

How many people are infected by Helicobacter?

significant portion (possibly 50%) of population is infected

6

Helicobacteria is present in patients with what?

-chronic gastritis and
-gastric ulcers

7

What are the symptoms of Helicobacter disease?

-Dyspepsia (indigestion)
-stomach pains
-nausea
-bloating
-belching
-sometimes vomiting
-sometimes black stool

8

Helicobacter can be possible causes of what?

-Gastric ulcers
-duodenal ulcers
-gastric cancer (carcinoma)

9

Helicobacter pylori is originally classified as ____

C. pyloridis

10

Helicobacter pylori infects how much of the population?

significant portion (possibly 50%) of the population infected

11

How do the flagella of H. pylori help adhesion?

the flagella help burrow in the mucus layer and to reach epithelial layer.

12

What does BabA stand for?

blood-group antigen binding adhesion

13

What does SabA stand for?

Sialic acid binding adhesion

14

What do the antigens SabA and BabA in H. pylori do?

they trigger inflammation and help Helicobacter with adhesion

15

What does urease from H. pylori help colonization?

It produces ammonia and buffers acid pH; triggers apoptosis (death of cells)

16

H. pylor can modifiy what? how is this a virulence factor?

by modifying its peptidoglycan which helps immune evasion

17

How does H. pylori's LPS play a role in virulence?

It binds to toll like receptors which can activate B cells and reduce pathology.

18

What are people with TLR (toll like receptor) at higher risk for when infected with H, pylori as well?

more prone to tissue damage and cancer

19

What toxin of H. pylori that causes tissue damage?

CagA (cytoxin associated gene A)

20

What type of secretion in H. pylori is involved in injecting CagA into gastric cells?

Type 4

21

cagA is a virulence of H. pylori located where?

on a pathogenicity island

22

CagA is a virulence of H. pylori that is associated with what?

gastric carcinoma

23

What does cagA do with several host genes?

Interacts

24

What is Tip-alpha

Tumor Necrosis factor alpha inducing protein; virulence of H. pylori

25

What is Tip-alpha associated with?

carcinogensis; hy. pylori virulence

26

Vaculoating cytotoxin A (vacA) is a virulence factor if H. pylori that causes what?

vacuole formation (large vesicles in host cells)

27

VacA targets what?

the mitochondria

28

VacA can induce what

apotosis

29

what is apotosis?

the death of cells

30

The vac A virulence is a major contributor to what? Why?

Gastric cancer; because of the increased occurences of mutation due to direct damage of DNA (free radicals primarliy ROS, NOS) and a deficient repair of mutations

31

How is H. pylori diagnosed

-based on symptoms of chronic gastritis, GERD (gastroesophageal reflex disease)
-blood antigen
-13C urea breath teast (urease test)
-antigen in stool
-Endoscopy, tissue staining with immunostain

32

How is H. pylori r treated?

triple/ quadruple therapy

33

What is triple/quadruple therapy in regards to H. pylori ?

Treatment in which Mentronidazole + tetracycline + Bismuth sulphate is used and sometimes also a proton pump inhibito (omeprazole) to allow healing

34

what are toll like recpetors?

a class of proteins that play a key role in innate immune system

35

H. pylori adhesin has what type of binding?

apical binding; apical colonization and signaling to known and unknown receptors on gastric epithelium

36

H. pylori directs what?

signal transduction

37

Upregulation of H. pylori transcription factors such as _____ leads to production of what?

upregulation of transcription factors such as NF-kB leads to the production of pro-inflammatory cytokines and chemokines

38

Secretion of mediators at the basolateral surfaces does what?

attracts immune cells to the site of infection

39

Upon host cell contact, H. pylori assembles what? Resulting in what?

T4SS (type 4 secretion) pili at the surface enabling (allowing) delivery of molecules from bacterial cytoplasm into host cells

40

What molecules at the surface of host cells are enabled into the host via T4SS?

Cag A and peptidoglycan

41

cag PAI proteins include

-CagA
-CagI
-CagL
-CagY

42

Cag PAI proteins interact with _____

integrin receptors

43

Interactions with phosphatidyserine (PS) and cholesterol in lipid rafts are inolved in ____ processing

T4SS

44

T4SS and CagA are involved in _____

numerous cellular effects including:

- disruption of cell-to-cell junctions (tight junctions and adherence junctions)

-Cytoskeletal rearrangement

-nuclear signaling