Normal Flora (Microbiota) of Humans

Question 1

Parasitism

Answer 1

microbe benefits while host is harmed

Question 2

commensalism

Answer 2

microbe benefits with no harm to host

Question 3

mutualism

Answer 3

both microbe and host benefit (~symbiosis)

Question 4

colonization

Answer 4

microbe gains access to person and sets up residence without causing disease

Question 5

carrier (reservoir) state:

Answer 5

colonization with the potential for transmission to other people

Question 6

In what ways to microbes benefit from host?

Answer 6

1. nutrient supply
   
   • from consumed food
   • from products of other bacteria
2. provision of a variety of ecologic niches
3. complex by stable environment

Question 7

In what ways does the microbiome benefit its host?

Answer 7

1. stimulation of immune system
2. promotion of epithelial cells proliferation and differentiation
3. fermentation of indigestible starches into SFA
4. degrade harmful compounds produced by other bacteria in the microbiome
5. essential nutrients from microbes (VitK, B12)
6. Competition or interference against pathogens.

Question 8

What are defects seen in germ free (gnotobiotic) mice?

Answer 8

1. immature lymphoid follicle & small Peyers patches
2. reduced product of IgA
3. reduced prod. antimicrobial pep
4. reduced number CD8+ intestinal epithelia cells & CD4+
5. increase susceptibility to infect fro enteric pathogens.
6. Lower body mass and fat composition

Question 9

Do microbes differentiate by environmental site in the human body?

Answer 9

yes,

• stool contains the riches diversity of bacteria
• large differences btw individuals in their microbiomes at diff sites.

Question 10

Bacteria floral in a normal person in community vs hospital or Long term care facility..

Answer 10

refer to slide19

Question 11

Dysbiosis

Answer 11

perturbed balance within the microbiome (mainly intestinal) leading to aberrant immune response and inflammation

Question 12

probiotic

Answer 12

live or attenuated microorganisms that may have beneficial effects in humans; usually intestinal

Question 13

prebiotic

Answer 13

ingredients in food that remain undigested, and which may stimulate either the growth or the activity of bacteria that are also beneficial to human health

Question 14

synbiotic

Answer 14

combination of probiotic and prebiotic

Question 15

Predisposing condition under which Staphylococcus epidermis causes disease?

Answer 15

if had a wound on your skin and gets into the blood.

can grow on artificial join, catheter

Question 16

Predisposing condition under which viridans steptococci causes disease?

Answer 16

abnormally found in heart valve which is common cause of bacterial endocarditis.
- normally found in mouth

Question 17

Predisposing condition under which Propionibacterium acnes causes disease?

Answer 17

can spread to the CSF

Question 18

Predisposing condition under which bacteroides fragilis causes disease?

Answer 18

causes intestinal infarction

Question 19

candida albicans

Answer 19

can lead to vaginal infections