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Flashcards in HIV Deck (46):
1

gp41, HIV

transmembrane protein(hookshot)
associates with gp120 on envelope surface

2

p17, HIV

matrix proteins

3

p24, HIV

capsid proteins

4

p7, HIV

nucleocapsid proteins

5

transmission of HIV

mucosal: sex or mother>>child @birth

parenteral: direct injection

6

how does HIV invade the body when it goes the mucosal route?

- DCs trap HIV and pass to/infect CD4+ Tcells

- Breach in endothelium

- Transcytosis

7

describe HIV cell surface interactions when infecting a cell

gp120 binds CD4

gp120 transforms and binds CCR5 or CXCR4

gp41 is exposed and extends to target cell, initiating fusion

8

tRNA lysine role in HIV infection

primer for RT

9

structural genes for HIV

gag, pol, env

gag and pol code polyproteins that are cleaved into respective structural proteins after translation

10

trans-activator genes?
what do they do?

tat and rev

tat - essential for HIV transcription; binds tat-activation region on all species; activates cellular promoters

rev - essentially binds and chaperones RNA out of the nucleus that hasnt been spliced(or just single spliced) and would otherwise be degraded w/out rev

11

what is the greatest hurdle(at the molecular level) for HIV eradication?

integration into the genome; there is a large pool of latent virus just sitting in cells which there isnt a good drug target for

12

role of Nef gene in HIV

down-regulates CD4, MHCI

induces FasL expression

13

role of Vif gene in HIV

targets APOBEC3G which is then degraded; otherwise it would cause massive inactivating mutation in HIV genome

14

role of Vpu gene in HIV

targets CD4 at the ER, preventing it from being expressed

15

role of Vpr gene in HIV

can keep cell in G2 phase which is ideal for RNA production

16

hurdles to producing a Vaccine for HIV

variably glycosylated envelope

highly mutagenic virus

integrates genome; latency

neutralizing epitopes only transiently expressed

17

most common transmission of HIV in US

most common transmission of HIV ww

US - MSM
WW - heterosexual transmission

18

fluids that transmit HIV

blood
breast milk
semen
vaginal/rectal fluids/secretions

19

what would cause a false negative for HIV serologic testing

"window period"
time between infection and antibody/antigen production

20

about how much time does it take for p24 antigen and HIV antibodies to appear after infection

p24 ~15 days (2 weeks)
antibodies ~25 days (3 weeks)

21

when is pro-viral DNA tested for by PCR?

diagnosis of infants < 18 months of age

22

symptoms of acute HIV infection

fever, lymphadenopathy, pharyngitis, rash, myalgia/arthralgia

**CD4 drops/viral load spikes @ start of HIV infection

23

normal CD4 cnt

800-1050 cells/mm3

can range from 500-1400 in uninfected individuals

24

HIV OI
pneumocystitis(PCP)

CD4 indication?
prophylaxis and when it should be given(primary/secondary)

CD4<200
give TMP-SMX as primary/secondary prophylaxis

25

HIV OI
toxoplasmosis

CD4 indication?
prophylaxis and when it should be given(primary/secondary)

CD4<100 and toxo IgG+
give primary/secondary prophylaxis of TMP-SMX

26

HIV OI
cryptococcus

CD4 indication?
prophylaxis and when it should be given(primary/secondary)

CD4<100
give only secondary prophylaxis of fluconazole

27

HIV OI
m. avium complex(MAC)

CD4 indication?
prophylaxis and when it should be given(primary/secondary)

CD4<50
give only primary prophylaxis of azithromycin

28

HIV OI
CMV

CD4 indication?
prophylaxis and when it should be given(primary/secondary)

CD4<50
give only secondary prophylaxis of valganciclovir

29

OIs for HIV most comon at CD4 200-500

TB
Oro-pharyngeal candidiasis
VZV(shingles)
kaposi's sarcoma(HHV-8)

30

maraviroc(MVC) mechanism

binds CCR5 coreceptor; blocks HIV from entering cell

wont work on mixed or CXCR4 virus profiles

31

enfuvirtide(T-20) mechanism

prevents change in gp41 that allows fusion of HIV to cell membrane

32

NRTIs

zidovudine
stavudine
didanosine
tenofovir
abacavir
lamivudine
emtricitabine

zestdla

33

NRTI toxicity

mitochondrial toxicity causing neuropathy, myopathy, LAcidosis, hepatic steatosis, pancreatitis, lipoatrophy

34

NRTI mechanism

stop chain elongation of RT

35

NNRTI mechanism

binds at non-catalytic site on RT; inhibits functionality

36

NNRTIs

nevirapine
efavirenz
etravirine
rilpivirine

37

resistance problems for NNRTIs

single mutations can cause cross-class resistance

38

NNRTI toxicities

rash; can progress to stevens-johnson

liver transaminase elevations/hepatitis

39

efavirenze toxicity

CNS effects(hallucinations, insomnia) on top of class-common rash/liver enzyme elevation

40

t1/2 of NNRTIs

VERY LONG; need to keep other meds going if stopping treatment to not cause resistance from NNRTI monotherapy due to long t1/2

41

integrase inhibitors

raltegravir
elvitegravir
doultegravir

ralph is an elite dueler

42

ritonavir mechanism; indications

protease inhibitor

cyp450 34a inhibitor; combined with other drugs to "boost" them

43

are NNRTI's effective against HIV-2

NO, NO THEY ARENT

44

protease inhibitor class toxicities

metabolic dysregulation
- hyperlipidemia
- increased potentiation of glucose intolerance

GI upset - nausea, diarrhea

Fat redistribution
- buffalo hump
- central/visceral adiposity

45

ART treatment in naive patient should be composed of which drug classes?

2 NRTIs +....
- 1 NNRTI or
- 1 PI(w/ritonavir boost)
- 1 II

46

what is the goal for the viral load after 1-4 months of therapy

see a log decrease in initial viral load