Microbiology

Question 1

normal flora of the skin

Answer 1

Staphylococcus epidermidis

Question 2

normal flora of the dental plaque

Answer 2

Strephylococcus mutans

Question 3

normal flora of the GI tract

Answer 3

anaerobes, E. coli

Question 4

normal flora of the vagina

Answer 4

Streptococcus agalaciae

Question 5

benefits of the normal flora

Answer 5

protection from disease (take up space, produce bacteriocidins)
nutritional/hormonal benefit ((produce vitamins B12/K, deconjugate bile salts and sex hormones)
immune system development
gut morphology and function development

Question 6

potential harmful effects of the normal flora

Answer 6

intestinal gas and body odor
dental caries and periodontal disease
can modify ingested chemicals to known carcinogens
opportunistic infections (take advantage in a state of vulnerability)

Question 7

virulence factors

Answer 7

biofilm production (Staph epi)
quorum sensing
capsules (Strep pneumo, Haemophilus influenza, Neisseria meningitides, Klebsiella, Baccilus anthracis)
intracellular survival (Salmonella, Myocobacterium tuberculosis, Legionella, Brucella, Rickettsiae, Listeria monocytogenes)
Fe binding (Vibrio cholera, Bacillus anthraces, Shigella)
Protein A (Staph aureus)
IgA protease (Neisseria gonorrhoeae, Neisseria meningitidis, Strep pneumo)
M protein (Strep progenies)
type 3 secretion system (Shigella, Salmonella, Yersinia pestis, Bordetella, Chlamydia trachomatis/pneumoniae)
exotoxins (Shigella, Clostridium, E. coli, Vibrio)
endotoxins (Salmonella, Shigella, E. coli, Neisseria)

Question 8

exotoxin

Answer 8

effector proteins secreted by bacteria

heat labile, specific action, non-febrile, inactivated toxin = toxoid

Question 9

endotoxin

Answer 9

part of the outer cell wall of gram negative bacteria (activity due to lipid A)
heat stable, produces fever, non-specific immune response (cytokine production/severe inflammation)

Question 10

MIC

Answer 10

minimal inhibitory concentration- concentration to inhibit growth

Question 11

MBC

Answer 11

minimal bactericidal concentration- concentration that kills bacteria

Question 12

breakpoint

Answer 12

the MIC used to designate between sensitive and resistant

Question 13

cytochrome P450 function

Answer 13

catalyzes the oxidation of drugs

Question 14

cytochrome P450 inhibitors

Answer 14

erythromycin, clarithromycin, ciprofloxacin, fluconazole, itraconazole

Question 15

cytochrome P450 inducers

Answer 15

rifampin, phenobarbital, carbamazepine, phenytoin, St. John’s wort

Question 16

general effects of glucocorticoids

Answer 16

metabolic effects
anti-inflammatory effects
immunosuppressive effects
neurologic- insomnia and euphoria, then depression
negative effects = “Cushingoid”- cataracts, ulcers, thin skin, hyperglycemia/HTN, infections, necrosis, glycosuria, osteoporosis/obesity, immunosuppression, DM

Question 17

metabolic effects of glucocorticoids

Answer 17

increased gluconeogenesis, lipolysis, protein breakdown, osteoclast activity
decreased glucose uptake and utilization

Question 18

anti-inflammatory effects of glucocorticoids

Answer 18

inhibits phospholipase A2, decreased expression of COX-2 (decreased prostaglandin production)

Question 19

immunosuppressive effects of glucocorticoids

Answer 19

increased neutrophil concentration in circulation (decreased migration to tissues and site of inflammation)
decreased lymphocytes, monocytes, eosinophil and basophil concentration in circulation
reduced ability of macrophages to phagocytose
reduced production of cytokines

Question 20

adverse effects of glucocorticoids

Answer 20

cataracts, ulcers, skin thinning, hyperglycemia/HTN, infection, necrosis, glycosuria, osteoporosis/obesity, immunosuppressive, diabetes

Question 21

anti-inflammatory and mineralocorticoid activity glucocorticoids

Answer 21

hydrocortisone, cortisone, prednisone, prednisolone, methylprednisolone

Question 22

only anti-inflammatory activity glucocorticoids

Answer 22

triamcinolone, betamethasone, dexamethasone

Question 23

immunosuppressive drugs

Answer 23

rituxamab, adalimumab, infliximab, etanercept, eculizumab, natalizumab

Question 24

rituximab mechanism

Answer 24

monoclonal antibody that depletes B lymphocytes

Question 25

adalimumab mechanism

Answer 25

anti-TNF monoclonal antibody

Question 26

infliximab mechanism

Answer 26

monoclonal antibody that binds to TNF-alpha

Question 27

etanercept mechanism

Answer 27

fusion protein that binds to TNF-alpha

Question 28

eculizumab mechanism

Answer 28

monoclonal antibody that binds to C5 | **need to give meningococcal vaccine prior to therapy

Question 29

natalizumab mechanism

Answer 29

monoclonal antibody against alpha-4-integrin (prevents leukocytes from moving across vascular endothelium)

Question 30

1st generation H1 histamine antagonists

Answer 30

diphenhydramine, hydroxyzine, meclisine, promethazine, chlorpheniramine, brompheniramie

Question 31

2nd generation H1 histamine antagonists

Answer 31

cetirizine, fexofenadine, loratadine

Question 32

IL4 function

Answer 32

B cell activation, class switching to IgG and IgE

Question 33

IL5 function

Answer 33

B cell activation, eosinophil growth and differentiation

Question 34

IL6 function

Answer 34

B cell activation, enhances Th2 cell development

Question 35

IL10 function

Answer 35

inhibits the generation of Th1 cells

Question 36

IL13 function

Answer 36

B cell activation, class switching to IgG and IgE

Question 37

IL2 function

Answer 37

T cell proliferation

Question 38

IFN gamma function

Answer 38

macrophage activation and increased HLA expression

Question 39

TNF-alpha function

Answer 39

macrophage activation and increased HLA expression

Question 40

function of Th1 cells

Answer 40

secrete IL2, IFN-gamma and TNF-alpha

Question 41

function of Th2 cells

Answer 41

secrete IL4, IL5, IL6, IL10, IL13

Question 42

innate immune response to bacterial pathogens

Answer 42

activation of the complement system recruitment of neutrophils and macrophages (via TLRs) induction of cytokine synthesis maturation of dendritic cells

Question 43

TLR function

Answer 43

induce dendritic cell maturation induce acute phase reactant production induce cytokine production (leads to neutrophil and monocyte recruitment) activates alternative complement cascade

Question 44

respiratory burst

Answer 44

destruction of internalized bacteria mediated by ROS key enzymes = NADPH oxidase requires NADPH

Question 45

innate immune response to viral pathogens

Answer 45

production of type 1 interferons (don't protect the infected cell but provide protection to neighboring cells) recruitment of NK cells (enhanced by IL2, IL12, IFN alpha, IFN beta) induction of cytokine synthesis maturation of dendritic cells