Helicobacter

Question 1

Helicobacter disease is gram _____

Answer 1

negative

Question 2

Helicobacter is ____ shape

Answer 2

Helical shaped

Question 3

Helicobacter disease is found where?

Answer 3

found in the stomach

Question 4

Helicobacter disease is what type of bacterium?

Answer 4

gram negative miicro-aerophilic bacterium

Question 5

How many people are infected by Helicobacter?

Answer 5

significant portion (possibly 50%) of population is infected

Question 6

Helicobacteria is present in patients with what?

Answer 6

• chronic gastritis and

- gastric ulcers

Question 7

What are the symptoms of Helicobacter disease?

Answer 7

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

Question 8

Helicobacter can be possible causes of what?

Answer 8

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

Question 9

Helicobacter pylori is originally classified as ____

Answer 9

C. pyloridis

Question 10

Helicobacter pylori infects how much of the population?

Answer 10

significant portion (possibly 50%) of the population infected

Question 11

How do the flagella of H. pylori help adhesion?

Answer 11

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

Question 12

What does BabA stand for?

Answer 12

blood-group antigen binding adhesion

Question 13

What does SabA stand for?

Answer 13

Sialic acid binding adhesion

Question 14

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

Answer 14

they trigger inflammation and help Helicobacter with adhesion

Question 15

What does urease from H. pylori help colonization?

Answer 15

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

Question 16

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

Answer 16

by modifying its peptidoglycan which helps immune evasion

Question 17

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

Answer 17

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

Question 18

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

Answer 18

more prone to tissue damage and cancer

Question 19

What toxin of H. pylori that causes tissue damage?

Answer 19

CagA (cytoxin associated gene A)

Question 20

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

Answer 20

Type 4

Question 21

cagA is a virulence of H. pylori located where?

Answer 21

on a pathogenicity island

Question 22

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

Answer 22

gastric carcinoma

Question 23

What does cagA do with several host genes?

Answer 23

Interacts

Question 24

What is Tip-alpha

Answer 24

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

Question 25

What is Tip-alpha associated with?

Answer 25

carcinogensis; hy. pylori virulence

Question 26

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

Answer 26

vacuole formation (large vesicles in host cells)

Question 27

VacA targets what?

Answer 27

the mitochondria

Question 28

VacA can induce what

Answer 28

apotosis

Question 29

what is apotosis?

Answer 29

the death of cells

Question 30

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

Answer 30

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

Question 31

How is H. pylori diagnosed

Answer 31

- 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

Question 32

How is H. pylori r treated?

Answer 32

triple/ quadruple therapy

Question 33

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

Answer 33

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

Question 34

what are toll like recpetors?

Answer 34

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

Question 35

H. pylori adhesin has what type of binding?

Answer 35

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

Question 36

H. pylori directs what?

Answer 36

signal transduction

Question 37

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

Answer 37

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

Question 38

Secretion of mediators at the basolateral surfaces does what?

Answer 38

attracts immune cells to the site of infection

Question 39

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

Answer 39

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

Question 40

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

Answer 40

Cag A and peptidoglycan

Question 41

cag PAI proteins include

Answer 41

- CagA - CagI - CagL - CagY

Question 42

Cag PAI proteins interact with _____

Answer 42

integrin receptors

Question 43

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

Answer 43

T4SS

Question 44

T4SS and CagA are involved in _____

Answer 44

numerous cellular effects including: - disruption of cell-to-cell junctions (tight junctions and adherence junctions) - Cytoskeletal rearrangement - nuclear signaling