Antibacteril protocols 7.3

Question 1

What are antisepsis? selected based on?

Answer 1

Agents that reduce the number of microbes on skin surfaces.

*selected for safety and efficacy

Question 2

1) alcohols have excellent activity against?
2) can dry the skin surface because?
3) inactivated by?
4) what should you do before applying alcohol?

Answer 2

• 1) excellent activity against all groups of organisms except spores
• 2) are nontoxic but can dry the skin surface because they remove lipids
• 3) do not have residual activity and are inactivated by organic matter
• 4) surface of the skin should be cleaned before alcohol is applied

Question 3

Iodophors are excellent ___ agents

Answer 3

antiseptic

Question 4

Iodophors activity is similar to? inactivated by? frequently used with?

Answer 4

have a range of activity similar to that of alcohols.
• are slightly more toxic to the skin than alcohol
• have limited residual activity
• inactivated by organic matter.
• Iodophors and iodine preparations are frequently used with alcohols

Question 5

1) Chlorhexidine has broad ____ activity
2) kills organisms at a slower rate than?
3) its activity persists or ends quickly
4) what decreases its effectiveness?

Answer 5

1) broad antimicrobial activity
2) kills organisms at a much slower rate than alcohol
3) Its activity persists
4) organic material and high pH levels decrease its effectiveness

Question 6

Parachlorometaxylenol(PCMX) is limited to?

2) is nontoxic or toxic?
3) used in what type of products?

Answer 6

1) is limited primarily to gram-positive bacteria
2) is nontoxic and has residual activity
3) used in hand washing products

Question 7

Triclosan

1) is active agaisnt?
2) commonly found in what products?
3) may cause developement of?
4) commonly used or phased out

Answer 7

1) active against bacteria but not much else
2) common antiseptic in deodorant soaps and toothpaste
3) May cause the development of antibiotic resistant strains of bacteria
4) Is BEING phased out

Question 8

Antibacterial spectrum

Answer 8

Range of activity of an antimicrobial against bacteria

Question 9

Broad-spectrum antibacterial drug

Answer 9

can inhibit a variety of gram-positiveand gram-negative bacteria

Question 10

narrow-spectrum antibacterial drug

Answer 10

is active against a limited variety of bacteria

Question 11

Bacteriostatic antibiotic

Answer 11

Antibiotic that inhibits the growth of bacteria but does not kill

Question 12

Bactericidal antibiotic

Answer 12

Antibiotic that kills bacteria

Question 13

Minimum inhibitory concentration (MIC)

Answer 13

The lowest antibiotic concentration that inhibits the growth of the bacteria is the MIC

Question 14

Minimum bactericidal concentration (MBC)

Answer 14

The lowest antibiotic concentration that kills 99.9% of the population is referred to as the MB

Question 15

Antibiotic combinations

Answer 15

Combinations of antibiotics to (1) broaden the antibacterial spectrum for empirical therapy, (2) prevent emergence of resistant organisms during therapy, and (3) achieve a synergistic killing

Question 16

Antibiotic synergism

Answer 16

Combinations of two antibiotics that have enhanced bactericidal activity when tested together compared with the activity of each antibiotic

Question 17

Antibiotic antagonism

Answer 17

Combination of antibiotics in which the activity of one antibiotic interferes with the activity of the other (e.g., the sum of the activity is less than the activity of the most active individual drug)

Question 18

β-Lactamase

Answer 18

An enzyme that hydrolyzes the β-lactam ring in the β- lactam class of antibiotics, thus inactivating the antibiotic

Question 19

Pasteurization

Answer 19

the heat treatment of milk or other liquids to reduce its total number of microorganisms

Question 20

Pasteurization

1) created by?
2) first used for?
3) reduces _____ load? this increases?
4) does NOT kill

Answer 20

1) Louis Pasteur
2) First used for controlling the spoilage of wine
3) reduces microbial load. This decreases spoilage and INCREASES shelf life
4) does not kill all organisms and therefore does not sterilize

Question 21

Pasteurization may not kill all organisms, but its does kill all organisms such as?

Answer 21

kills all known pathogenic bacteria that can be transmitted in milk
**tuberculosis, brucellosis, Q fever, and typhoid fever

Question 22

How do you achieve pasteurization?

Answer 22

the liquid is brought to 71°C for 15 seconds OR even higher temperatures for shorter time periods
**then liquid is rapidly cooled-flash pasteurization

Question 23

Milk can also be pasteurized by heating it in large vats at what temp?

Answer 23

63–66°C for 30 min

Question 24

What is common mechanism of antibiotic activity?

Answer 24

Inhibition of Cell Wall Synthesis

Question 25

Most common cell wall inhibiting antibiotics are classififed as?

Answer 25

β-lactam antibiotics; named this because they share a common β-lactam ring
structure
*Ex: penicillins, cephalosporins, cephamycins, carbapenems, monobactams, β-lactamase inhibitors

Question 26

Target penicillin-binding proteins (PBPs) that are responsible for?

Answer 26

peptidoglycan cross-links

Question 27

Disruption of peptidoglycan synthesis triggers autolysins that degrade?

Answer 27

existing cell wall, thus killing the bacterium (bacteriocidal)

Question 28

*Bacteria can become resistant to β-lactam antibiotics by? (3)

Answer 28

(1) decreased concentration of the antibiotic at the cell wall target site
(2) decreased binding of the antibiotic to the PBP
(3) hydrolysis of the antibiotic by bacterial enzymes, β-lactamases

Question 29

The basic compound for penicillins is obtained from a culture of mold called? Why used so much?

Answer 29

Penicillium chrysogenum

*Used bc they are highly effective with extremely low toxicity

Question 30

If Penicillium chrysogenum mold is grown by fermentation, large amounts of ______ are produced?

Answer 30

6- aminopenicillanic acid are produced

Question 31

Modification of 6-aminopenicillanic acid from penicillium mold increases resistance to

Answer 31

stomach acids, increases absorption in gut, increases resistance to penicillinase, increases spectrum of activity that includes gram-negative bacteria

Question 32

Penicillin G is inactivated or resistant to gastric acids?

Answer 32

is inactivated by gastric acid; thus it is used mainly as an intravenous drug

Question 33

Penicillin V is inactivated or resistant to gastric acids?

Answer 33

is more resistant to acid and is the preferred oral form for the treatment of susceptible bacteria