Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Winter course I > Gut > Flashcards

Gut Flashcards

1
Q

name the 4 components of the small intestine and their function

A
  1. stomach; stir and mix food with gastric juices
  2. duodenum
  3. jejunum; majority of nutrient uptake
  4. ileum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

name the 8 components of the colon and their function

A
  1. cecum; receive food particles from ileum
  2. vermiform appendix; site of appendicitis
  3. ascending colon; water absorption
  4. transverse colon; water absorption
  5. descending colon; waste storage
  6. sigmoid colon; carry waste to rectum
  7. rectum
  8. anus; ejection of fecal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

name the 4 immune cells found in the Peyer’s patch

A

M-cells, DC, B/T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

name the 3 immune cells found in the lamina propria

A

macrophages, DC, mesenteric LN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the histological difference between small intestine and colon?

A

small intestine has folds and villi for surface enlargement for nutrient uptake, colon has no villi and folds and more bacteria (but ileum has more diverse bacteria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

which lymphoid tissue drains the intestinal tract?

A

mesenteric LN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

which cells can be found in the villus and crypt?

A

villus; goblet cells
crypt; Paneth cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

name the 4 characteristics of the host-microbial symbiosis in the GI tract

A
  1. bacteria facilitate digestion and absorption of nutrients
  2. bacteria-derived signals needed for normal intestinal physiology
  3. commensal bacteria limit pathogen colonization
  4. host provides a protected and nutrient-rich environment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

name the 5 functions of the epithelial barrier

A
  1. microvillar extensions
  2. epithelial-cell tight junctions
  3. secreted mucins by goblet cells
  4. epithelial transcytosis of IgA
  5. antimicrobial peptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

name the 3 functions of microbial sampling in the intestine

A
  1. antigen uptake by M-cells
  2. antigen uptake by APC
  3. passive diffusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

name the 4 differences in innate immune regulation between small intestine and colon

A

small intestine vs. colon;
1. presence of M cells vs. absence
2. thin mucus layer vs. thick
3. presence of Paneth cells vs. absence
4. Peyer’s patches vs. isolated lymphoid follicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe what happens when MUC2 is lacking

A

loss of colon mucus, thus more susceptible to bacterial infections and intestinal inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

describe what happens when Paneth cells and AMPs are lacking

A

increased bacterial translocation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the role of NF-kB signalling in the gut?

A

intestinal homeostasis by NF-kB signaling; maintains mucosal barrier integrity and activates innate immune cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what happens when there is repetitive microbial interaction with the epithelium?

A

desensitization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

name the 2 functions of epithelial cells in the GI tract

A
  1. activation (inflammatory protection against invading pathogens); epithelial signals and NF-kB signaling
  2. desensitization (anti-inflammatory maintenance of tissue integrity); epithelial signals and NF-kB inhibition
17
Q

describe the function of macrophages in the intestine during homeostasis and inflammation

A
  • homeostasis; monocytes recruit to the lamina propria and differentiate into anergic macrophages
  • inflammation; monocytes recruit to the lamina propria and differentiate into inflammatory macrophages producing high levels of pro-inflammatory cytokines and chemokines
18
Q

name the inflammatory and regulatory T cell subsets in the intestine

A

inflammatory; Th1/2/17
regulatory; Tr1 (IL-10) and FoxP3+ Treg

19
Q

how is acquired tolerance maintained for mucosal homeostasis?

A

ingested soluble antigen is presented by PP and MLN-DC in mucosa draining lymphoid sites resulting in suppressive T cell response

20
Q

true or false? loss of tolerance is associated with reduced numbers of FoxP3+ T cells

A

true, so inducible FoxP3+ Tregs are essential for differentiation of mucosally induced Treg cells in the MLN (suppressive capacity)

21
Q

true or false? The lamina propria is populated by effector memory T cells

A

true

22
Q

name the 2 requirements for mucosal tolerance

A
  1. microenvironment (soluble factors)
  2. antigen presenting cell (DC)
23
Q

what enhances FoxP3+ iTreg differentiation in the MLN?

A
  • CD103+ DC producing vitamin A derived retinoic acid
  • TGFb production in the MLN
24
Q

what determines IL-10 secreting Treg induction in colon?

A

bacterial colonization

25
Q

what is the function of NOD2 in epithelium, stem cells and APCs?

A

epithelium:
- production of AMP by Paneth cells
stem cells:
- NOD2 induces stem cell survival through resistance to oxidative stress
APCs:
- NOD2 enhances bacterial through inflammasome-mediated caspase-1 activation and downregulates production of pro-inflammatory cytokines

26
Q

describe what happens when NEMO is deficient in epithelial cells

A

inhibition of NF-kB signaling and sensitizes epithelial cells to TNF-induced apoptosis –> severe chronic intestinal inflammation (IBD)

27
Q

describe what happens when IL-10 is deficient

A
  • develop enterocolitis to commensal Helicobacter hepaticus
  • celiac disease
28
Q

name the 4 histopathology characteristics in Celiac disease

A
  1. duodenal crypt hyperplasia
  2. duodenal villous atrophy
  3. increased numbers of CD8+ restricted intraepithelial lymphocytes (IEL)
  4. gliadin-specific IFNy secreting CD4+ T cells in the lamina propria
29
Q

name the 2 characteristics in the serum and genetics in Celiac disease

A
  1. anti-tissue transglutaminase-2 (TG2) antibodies
  2. genetic susceptibility HLA-DQ2/8
30
Q

describe the pathogenesis of Celiac disease

A
  1. CD4+ T cell derived IFNy causes epithelial stress and activated cytotoxic IEL
  2. IL-15 production by epithelial cells co-stimulates cytotoxic IEL
  3. cytotoxic CD8+ T IEL kill epithelial cells
31
Q

name the 5 histopathology characteristics of IBD

A
  1. cyrpt distorion and atrophy
  2. increase in lymphocytes in lamina propria
  3. crypt abscesses and ulceration
  4. epithelial mucin depletion
32
Q

name a treatment for IBD

A

infliximab (anti-TNF) provides mucosal healing

Winter course I (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions