1-4 part A

Question 1

chemical compounds used to treat disease

Answer 1

chemotherapeutic agents

Question 2

destroy pathogenics microbes or inhibit their growth within host

Answer 2

antimicrobials

Question 3

destroy or inhibit bacteria

Answer 3

antibiotics

Question 4

ability of drug to kill or inhibit pathogen while damaging host as little as possible

Answer 4

selective toxicity

Question 5

drug level required for clinical treatment

Answer 5

therapeutic dose

Question 6

drug level at which drug becomes too toxic for patient (produces side effects)

Answer 6

toxic dose

Question 7

ratio of toxic dose to therapeutic dose

Answer 7

therapeutic index

Question 8

kills bacteria

Answer 8

bacteriocidal antibiotics

Question 9

inhibit growth of bacteria

Answer 9

bacteriostatic antibiotics

Question 10

attack many different bacteria (gram + and gram -)

Answer 10

broad-spectrum antibiotics

Question 11

attack only a few different bacteria

Answer 11

narrow-spectrum antibiotics

Question 12

lowest concentration of drug that inhibits growth of pathogen

Answer 12

minimal inhibitory concentration (MIC)

Question 13

lowest concentration of drug that kills pathogen

Answer 13

minimal bacteriocidal concentration (MBC)

Question 14

what are the two techniques routinely used to determine MIC and MBC

Answer 14

dilution susceptibility Tests and disk diffusion tests
with Kirby-Bauer method

Question 15

this test involves inoculating media containing different concentrations of drug.

broth or agar with lowest concentration showing no growth is MIC

if borth used, tubes showing NO growth can be subcultured into drug-free medium

Answer 15

dilution susceptobility tests

Question 16

in dilution susceptibility tests, broth from which microbe cannot be recovered is

Answer 16

MBC

Question 17

disks impregnated with specific drugs are placed on agar plates inoculated with test microbe.

the drug diffuses from disk into agar, establishing concentration gradient

Answer 17

disk diffusion tests

Question 18

what do you observe/measure in disk diffusion tests

Answer 18

observe clear zones (no growth) around disks. this is the zone of inhibition

(no zone of inhibition means the bacteria is resistant to the antibiotic)

Question 19

the concentration of drugs in the blood at an infection site must be (<,>,=) MIC to be effective

Answer 19

> MIC

Question 20

1. ability of a drug to reach site of infection
2. ability of drug to reach concens. in body that exceed MIC of pathogen
3. susceptibility of pathogen to drug

Answer 20

are all factors influencing the effectiveness of antimicrobial drugs

Question 21

the ability of a drug to reach the site of infection depends on

Answer 21

on mode of administration and drug can be excluded by blood clots or necrotic tissue (abscess)

Question 22

modes of administration for antibiotics

Answer 22

oral (some drugs destroyed by stomach acid)
topical
parenteral route

Question 23

what are factors that influence ability of drug to reach concens. exceeding MIC

Answer 23

amount administered, route, speed of uptake, and rate of clearance (elimination) from the body

Question 24

1. does a drug require bacterial cell growth to be effective?
2. speed of action of drug (kills or stops bacterial growth within 1 generation??)

these are questions that relate to

Answer 24

the susceptibility of pathogen to drug

Question 25

what are the 4 mechanisms of action of antimicrobial agents:

Answer 25

1. disruption of bacterial cell wall
2. inhibition of protein synthesis
3. inhibition of nucleic acid synthesis
4. antimetabolites