Antivirals

Question 1

What are the stages in the pathogenesis of HIV

Answer 1

1) HIV contracted
2) Primary infection
3) host immune system contains it
4) latent phase
5) overtime CD4 falls as does the immune function.
6) symptoms occur
7) Initially non- specific.

Question 2

How is HIV contracted

Answer 2

mother to baby, sex or IV

Question 3

Drug used for HIV

Answer 3

T3-3 Drugs in one.

Question 4

What type of viruses cause acute infection.

Answer 4

RNA viruses

Question 5

Examples of acute infections

Answer 5

Influenza, measles, mumps, hepatitis A virus.

Question 6

What type of viruses cause chronic infection

Answer 6

DNA viruses

Question 7

2 types of chronic viral infection.

Answer 7

Latent- come out under stress.

Persistent-replicate all the time and are found in blood- HIV, Hep B.

Question 8

What does viruses consist of

Answer 8

nucleic acid- DNA or RNA
protein coat
lipid envelope derived from the cells they grow in.

Question 9

why don’t viruses which infect the GI tract have an envelope

Answer 9

to withstand the ph- envelope proteins would otherwise be destroyed.

Question 10

which 2 gene types make up a virus

Answer 10

Structural- make virus

Non-structural- take over host machinery.

Question 11

Mechanism of viral replication

Answer 11

1) virus attaches to a cell
2) cell entry
3) virus uncoating
4) early proteins produced.
5) Replication
6)Latent transcription and translation
7)virus assembly
virus release

Question 12

Prime target of antivirals

Answer 12

Polymerases.

Question 13

How does AZT (azidothymidine) work

Answer 13

mimics the binding blocks used for DNA and RNA synthesis.

changes OH group to NH3 on bases.

Question 14

what type of antiviral is AZT

Answer 14

Nucleoside reverse transcriptase Inhibitor.

Question 15

2 types of NRTI’s

Answer 15

Pyrimidine analogues.- C an T

Purine analogues.- A and G.

Question 16

Thymidine analogues

Answer 16

zidovudine

Question 17

Cytosine analogue

Answer 17

Lamivudine

Question 18

Adenine and Guanidine analogues

Answer 18

Abacavir

Tenofovir

Question 19

NRTI’s active against HBV

Answer 19

Lamivudine

Tenofovir

Question 20

Examples of non- nucleoside reverse transcriptase (NNRTI’s)

Answer 20

Efavirenz

Nevirapine.

Question 21

How do NNRTI work

Answer 21

Bind to different parts of the polymerase and inhibit it.

Question 22

Examples of protein inhibitors.

Answer 22

Atazanavir
Darunavir
Fospamprenavir
Lopinavir
Nelfinavir
Ritonavir*- now used to boost the level of other protein inhibitiors which are brokendown by liver enzymes.
Saquinavir
Aspartate protease

Question 23

How does fusion inhibitors work and a example

Answer 23

block virus fusing with membrane- given IM

Enfuviritide

Question 24

How do Intergrase inhibitors work

Answer 24

prevents virus incorporating in the host genome. Not toxic.

Question 25

How do  Chemokine receptor antagonsits work

Answer 25

prevent s entry
HIV requires CC5 to enter the cell as it is a co- receptor.
Maraviroc (CCR-5)

Question 26

What does HAART stand for

Answer 26

Highly active antiretroviral therapy

Question 27

What does HAART consist of and what is it’s function

Answer 27

– 2 NRTIs + NNRTI
– 2 NRTIs + boosted PI
Aims to switch of virus replication can cause liver toxicity.

Question 28

what mutation arises due to resistance to Lamivudine

Answer 28

M184V

Question 29

What mutation provides resistance to HIV.

Answer 29

CCR5 delta 32 - chnage in CCR5 means that HIV cannot bind

Question 30

2 drugs which sure Hep C

Answer 30

Interferons and ribavirin

Question 31

How long do interferons need to be given for

Answer 31

3-12 months.

Question 32

Important antivirals

Answer 32

Aciclovir- HSV and VZC
Ganciclovir- CMV
Oseltamivir and Zanamavir- (neurainidase inhibitors)- flu
Ribavirin- Hep C and RSV
Interferons- Hep C and B.