L14- Gut Microbiota Changes

Question 1

What are probiotics

Answer 1

Lige organisms eg bifudo and lactobacillus in yoghurt which feed on prebiotics

Question 2

What srw prebiotics

Answer 2

Indigestible fibre eg from fruit or potatoes to promote digestion and heslthy gut

Question 3

Give examples of how disease change microbiots

Answer 3

Roseburia cox et al 2013- reduced in type 2 diabrtes whcih sffects appetite,and insulin sensitivity etc

Or bifido in sha 2013 - reduces inflammation and uc symptoms

Question 4

Waht js rhe largest immune organ

Answer 4

The gut. Has most immune cells

Question 5

Which 2 layers of muscle does it have

Answer 5

Circular/inner and longitudinal

Question 6

What are corcular for

Answer 6

Peristalsis

Question 7

What is the mcuosal smooth muscle called

Answer 7

Mucosae muscularis

Question 8

What is the connrctive tossue around mucosa

Answer 8

Submucosa

Question 9

What does serosa have (outer layer of gut£

Answer 9

Epithelial with lubricant

Question 10

Which part of gut forms some peritoneum

Answer 10

Serosa

Question 11

Where is the mucosal layer biggest and why

Answer 11

Li/colon as this is nutrient poor so fermentation occurs more = more scfa too

Question 12

Why is stool not representativr of guy

Answer 12

Only microbiota at didtal colon and rectum. And not necessarily associated with mcuosa

Question 13

What is the perfrct scenario for stool sampling

Answer 13

Frozen stool samples and aequwnced asap for functional analysis

Question 14

What is the solution to problmeatic sotrage of stool in freezers

Answer 14

Buffered stool which presevred it for 60 days

Question 15

What is the ossue with buffered stool

Answer 15

It kill microbiota and so cant do functional analysis, only sequencing

Question 16

Which tools are used for sampling of mucosal epithelial

Answer 16

Brushes and biopsies

Question 17

What is yood withbusing these eg in ibd patients

Answer 17

Can compare samples from inflamed areas vs non inflamed

Question 18

Why sould you need to amplify the samples gia 16s rrna

Answer 18

Low biomass in samples

Question 19

Why are samples not taken after colonscopies for 2 weeks

Answer 19

Because the bowels get cleaned gia diarrhoea losing microbiota

Question 20

Name 3 bacteria whichd egrade mucus in fermentation tonproduce scfa (but also issues)

Answer 20

B theta, precotella, Akkermansia muciniphila

Question 21

Name some impacts of butyrate

Answer 21

Anti cancer (chen 2018)
Glucose and energy metabolism
Consumtion of o2 by colonocytes via b oxidation
Mucin (blacher 2017)

Question 22

Why is consumption of oxygen of coloncytes important

Answer 22

Holds the aerobic va anwrobic barrier for the obligate anaerobes

Question 23

Which scra is needed for gluconeogenesis, appetite reg, t regs

Answer 23

Proprionate

Question 24

What does acetate do which xan cause obesity

Answer 24

Lipo genesis

Question 25

Which article disxusses micorbiota and obesity

Answer 25

Chambers et al 2018

Question 26

Which bacteria associated with plsnt diets are lowered eg prevotella

Answer 26

Firmicutes

Question 27

Which are associated with hfd

Answer 27

Bacteroidetes

Question 28

Which is suggetsed to be a therapy for obesity/diabetes

Answer 28

Akkermansia muciniphila

Question 29

Which scfa does it produce

Answer 29

All 3

Question 30

Which hormones does proprionate increase to refuce appetite (chambers 2018)

Answer 30

Pyy and leptin

Question 31

Which hormone from priprionate increases insulin release

Answer 31

Glucagon like peptide 1 GLP1

Question 32

What is buttrate correlated to (meaning low firmicutes is an issue)

Answer 32

Improved insulin sensitivty

Question 33

Tive some examples of bacteria living in nuteient rich si

Answer 33

Proteobacteria ef exoli, lactobacillus

Question 34

Why isnt fmt limited to genetics

Answer 34

Genetics was found not to really impact on microbiota

Question 35

In the development period -3-14 months. What is tiven by breastfeeding

Answer 35

Bifido, lactobacillus, lower ecoli proteobacteria = good

Question 36

Which bscteria is most stable overtime

Answer 36

Bifido

Question 37

Which bacteria is less stable overtime

Answer 37

Clostridia (firmicute)

Question 38

Do bacteroidetes stabilise ober yime

Answer 38

Yes when given solid food

Question 39

How much does microbiota reduce before colonsocpy

Answer 39

31 fold

Question 40

Which article discusses the overcoming of colonisstion resistance by bacteria

Answer 40

Kamada 2013

Question 41

How does b theta cause both ehec and salmonella growth

Answer 41

Fucose releaae from mucon iupregs lee and t3ss in ehec Succinate = cdifficile and salmonella growth and mucinase by ehec

Question 42

What do commensals release which is used to generate tetrathionste as an aea by salmonella so it can use ethanolamine

Answer 42

H2s hydrogen sultide

Question 43

What does ehec use an an aea

Answer 43

Nitrates for nitrate resp (trom duox2 for h peroxide, nos to form nitrates, via inflammation)

Question 44

Whoch thing from eli cells in inflammation only can blooc iron of commensals but not salmonella

Answer 44

Lipocallin 2. Blocks fommensal sideorophore not salmonellas

Question 45

What donjnates over firmicutes in western diets with less plant degrading enzymes

Answer 45

Bacteroidetes

Question 46

How does c diff spread

Answer 46

Spores and faecal oral route

Question 47

Give an outbreak of mortailit by c didf and why

Answer 47

Quebec 2000 | Due to tcdC gene which allowed unrestricted toxin produced

Question 48

What is most used antibootic for it

Answer 48

Vancomycin for relapses and severe eg diarrhoea

Question 49

What type of antibiotic is fidaxomycin

Answer 49

Macrocyclic. Blocks rna polymerase of c diff

Question 50

What is it for

Answer 50

Sustained and less recurrwnt infections more thwn vancomycin

Question 51

Why is fmt used

Answer 51

Bacteria which outcompete eg sach biulardii and thuringiensis

Question 52

How is fmt given

Answer 52

Endoscopy or colonscopy

Question 53

What does it need to be screened for

Answer 53

Gisrdia and c diff

Question 54

What is the cure rate compared to bancomycin

Answer 54

80-90 vs 30

Question 55

What are the issues with fmt

Answer 55

Weight gain due to different way it affects lipid and glucose metabolism