micro- antimicrobial agents

Question 1

definition of an antibiotic

Answer 1

the products of microbes that in dilute solution inhibit or kill organisms

Question 2

what might we do to naturally occurring antibiotics

Answer 2

we may modify them to give synthetic derivatives

Question 3

define antimicrobial agents

Answer 3

include antibiotics and synthetic compounds that have the same effect

Question 4

what are the two types of antibiotics

Answer 4

bacteriostatic

bacteriocidal

Question 5

what does bacteriostatic mean

Answer 5

inhibit microbes so growth stops

Question 6

what does bacteriocidal mean

Answer 6

kill microbes

Question 7

give an example of a bacteriocidal antibiotic

Answer 7

gentamicin

Question 8

give an example of a bacteriostatic antibiotic

Answer 8

chloramphenicol

Question 9

how do we determine which drug is used to treat which bacteria

Answer 9

susceptibility testing
using isolated bacteria- different drug discs

epsilon testing

Question 10

what do we look for when susceptibility testing and epsilon testing

Answer 10

the largest zone of inhibition

and also if there is any mutant species as there is no zone of inhibition

Question 11

define minimum inhibitory conc

Answer 11

Lowest conc of antibiotic that prevents visible growth of a particular bacterium

Question 12

define minimum bactericidal conc

Answer 12

Lowest conc of antibiotic that kills a specific bacterium

determined using dilution methods

Question 13

what is the issue with dilution methods

Answer 13

time consuming- as need to make the correct dilution factor

Question 14

what is selective toxicity

Answer 14

the idea that bacteria have a different metabolism than humans and therefore the antibiotics will act on bacteria but not humans

Question 15

what is the issue with selective toxicity

Answer 15

doesn’t always work eg
a penicillin allergy is due to the thiazolidine ring
but the B lactam ring also in penicillin is the thing that gives the antibiotic activity

Question 16

which microbes metabolism is most similar to humans

Answer 16

fungi and protozoa

Question 17

why can we not use antibiotics on a virus

Answer 17

as a virus relies completely on the human host cell to replicate

Question 18

what is the main issue with antiviral, anti fungal and anti protists drugs

Answer 18

more limited in their scope and more toxic to humans

Question 19

what are some key points in the HIV virus replication cycle

Answer 19

1. Entry
   
   2. Uncoating
   3. Reverse transcription
   4. Integration
   5. Protease inhibition
   6. Virus replication and assembly
      Virus release

Question 20

what does antisense RNA do

Answer 20

used to inhibit transcription factors

Question 21

describe antisense RNA

Answer 21

short sequence of RNA that compromises the reverse of an MRNA
therefore binds to the MRNA and prevents translation

Question 22

what treatment and infection is given for influenza A

Answer 22

amantadine

rimantadine

Question 23

what is amantadine and rimantadine used for

Answer 23

the treatment and prevention fo influenza A

Question 24

how does amantadine and rimantadine work

Answer 24

by targeting entry and uncoating steps

Question 25

how does acilovir work

Answer 25

a nucleoside analogue that treats herpes simplex and varicella zoster virus

Question 26

what antimicrobial agent treats herpes simplex and varicella zoster virus

Answer 26

acilovir

Question 27

what is gancylovir

Answer 27

derivative of acilovir

Question 28

what tx is against cytomegalovirus

Answer 28

gancylovir

Question 29

what is ribavirin against

Answer 29

broad spectrum to treat respiratory syncytial virus

Question 30

which tx is for respiratory syncytial virus

Answer 30

ribavirin

Question 31

describe zidovudine and lamivudine

Answer 31

reverse transcriptase inhibitors

Question 32

give examples of some reverse transcriptase inhibitors

Answer 32

zidovudine | lamivudine

Question 33

describe nelfinavir

Answer 33

is a protease inhibitor that can hydrolyse polyproteins produced by viruses

Question 34

give an example of a protease inhibitor

Answer 34

nelfinavir

Question 35

what does HAART stand for

Answer 35

highly active antiretroviral therapy

Question 36

what is HAART used for

Answer 36

pts with aids

Question 37

describe tamiflu and relenza

Answer 37

neuraminidase inhibitors

Question 38

what do neuraminidase inhibitors do

Answer 38

prevent the release of viruses from infected cells

Question 39

give examples of anti fungal agents

Answer 39

nystatin

Question 40

what is nystatin used for

Answer 40

oral and genital candida infections

Question 41

what are polyenes

Answer 41

act by binding with sterols in eukaryotic membranes causing destabilisation

Question 42

what is the issue for amphotericin B

Answer 42

potentially toxic to humans given with a second anti fungal/suspension administered with 5- flucytosine

Question 43

describe 5 flucytosine

Answer 43

Synthetic pyrimidine that is metabolised in fungi to 5 fluorouracil and active against pathogenic yeasts It interferes with the synthesis of nucleic acids

Question 44

describe the azole group

Answer 44

large group that inhibit ergosterol synthesis leading to membrane leakage

Question 45

what are the two groups of azaleas

Answer 45

imidazoles | triazoles

Question 46

give examples of imidazole

Answer 46

micronazole | chotrimazole

Question 47

what is the issue with micronazole

Answer 47

too toxic to use systemically but can be used topical

Question 48

give examples of triazoles

Answer 48

flucanazole, itraconaole

Question 49

which antifungal agent is used against yeast

Answer 49

flucanazole

Question 50

what is fluconazole used for

Answer 50

yeast infections

Question 51

what is terbinafine used for

Answer 51

used for skin and nail infections

Question 52

what tx can be used for skin and nail infections

Answer 52

terbinafine

Question 53

what is griseofulvin

Answer 53

a true antibiotic used for ringworm and other fungal infections of skin and nails

Question 54

what tx can be used for ringworm or skin and nail infection

Answer 54

griseofulvin

Question 55

give some examples of antiprotist agents

Answer 55

chloroquine | mefloquine

Question 56

how does metronidazole work

Answer 56

targets DNA and membrane integrity

Question 57

what does metronidazole treat

Answer 57

anaerobic bacteria | T vaginalis

Question 58

what do we use for anaerobic bacteria and T vaginalis

Answer 58

metronidazole

Question 59

what does bacitracin

Answer 59

interferes with the bacterial cell well

Question 60

give examples of cell wall synthesis inhibitors

Answer 60

cycloserine B lactams glycopeptides

Question 61

what do cycloserine, B lactams and glycopeptides

Answer 61

cell wall synthesis inhibitors

Question 62

give examples B lactam antibiotics

Answer 62

monobactams | cephalosporin

Question 63

what is monobactams against

Answer 63

gram -ve bacteria

Question 64

which agents can affect membrane integrity

Answer 64

Polymyxins Metronidazole Gramicidins

Question 65

which agents affect DNA metabolism

Answer 65

folic acid | trimethoprim

Question 66

which agents affect DNA

Answer 66

Metronidazole levofloxacin ciprofloxacin nalidixic acid

Question 67

which agents affect protein synthesis

Answer 67

tetracycline chloramphenicol macrolides aminocycosides

Question 68

give examples of aminoglycosides

Answer 68

streptomycin | getamycin

Question 69

what are some side effects of aminoglycosides

Answer 69

streptomycin | gatamycin

Question 70

which agents are against RNA synthesis

Answer 70

rifampicin | streptomycin

Question 71

what does rifampicin do

Answer 71

inhibits bacterial RNA polymerase used to treat TB prophylaxis of meningitis