Antimicrobials

Question 1

What is the best way of stopping a virus?

Answer 1

Vaccine - immunisation

Or stop it attaching to host cells

Question 2

What inhibits penetration and uncoating of influenza A virus?

Answer 2

Amantadine

Question 3

What does idoxuridine do?

Answer 3

Prevents viral multiplication

Iodine interferes with DNA replication

Question 4

What are aciclovir and vidarabine?

Answer 4

Prevents viral replication

A DNA polymerase inhibitor

Question 5

What is zidovudine?

Answer 5

Reverse transcriptase inhibitor

Question 6

What does zidovudine treat?

Answer 6

FIV positive cats

Question 7

What is virbagen used to treat?

Answer 7

Parvovirus

Question 8

What are class 3 reactions in bacteria?

Answer 8

Complicated reactions involved in the synthesis of bacteria
they are specific to bacteria
antibacterial drugs target class 3 reactions

Question 9

What is the best class 3 reaction to target in bacteria?

Answer 9

cell wall synthesis

Question 10

What type of cell wall do gram positive bacteria have?

Answer 10

Thick cell wall - peptidoglycan

no outer membrane

Question 11

What type of cell wall do gram negative bacteria have?

Answer 11

Thin cell wall

outer membrane

Question 12

What antibacterials target the peptidoglycan structure?

Answer 12

beta-lactams eg. penicillin

Question 13

What part of the cell wall synthesis do beta lactams target?

Answer 13

Transpeptidases which cross link the peptidoglycan

Question 14

What is clavulanic acid?

Answer 14

Beta lactamase inhibitor

Question 15

What are the 3 stages of ribosomal protein synthesis?

Answer 15

Initiation - attach mRNA and tRNA
Elongation - transpeptidation
Termination

Question 16

What antibacterials compete with tRNA for the A site?

Answer 16

Tetracyclines

Question 17

What do sulphonamides target?

Answer 17

Bacterial folate synthesis - not in mammals as get from diet

Question 18

What are bacterial methods of causing antimicrobial resistance?

Answer 18

Mutations
Plasmids
Transfer of genes
inactivation of drug
alter binding site
produce efflux pump to get rid of drug

Question 19

What are dermatophytes?

Answer 19

Cause skin disease

Question 20

What fungal species causes guttoral pouch mycosis?

Answer 20

Aspergillus

Question 21

What does fungistatic mean?

Answer 21

Slow the growth - take a while to take effect

Question 22

Where do antimycotics target?

Answer 22

Fungal cell wall or fungal cell membrane

Question 23

How do polyenes eg. amphotericin work?

Answer 23

Binds to ergosterol

forms pore in the cell membrane

Question 24

What is a problem with using amphotericin?

Answer 24

causes nephrotoxicity

Question 25

What does the fungal cell membrane contain?

Answer 25

Ergosterol

Question 26

What does the fungal cell wall contain?

Answer 26

Glucans

Question 27

How do terbinafine and azoles work?

Answer 27

interfere with the production pathway of ergosterol

Question 28

What enzyme does imidazoles target?

Answer 28

cytochrome p450

Question 29

How are azoles administered?

Answer 29

Orally

Question 30

What do echinocandins cause?

Answer 30

Reduced glucan synthesis - cell wall loses integrity and lyses