human virology......part 3............... Flashcards
Where did AIDS originate?
brazzavile, africa - through monkeys (hunting = blood = travel)
spread really fast to cities along the transAFRICA highways
HIV/AIDS is linked to two rare diseases (pretty much diagnoses you)
opportunistic infections (PCP - fungal pneumocytisis carinii pneumonia) rare cancer (Kaposi's Sarcoma (KS)
Everyone thought it was only in the gay community, but now we know..
it can be IV drug use, blood transfusions (hemophilia A), female sex partners too
The process of HIV to AIDS is divided into three stages, which are…
1/ Acute infection (flu like- feels like you have something but you dont know what)
2/ Chronic Subclinical - when the antibodies go super high (hard to diagnosis)
3/ AIDS ( when the helper t cells are completely decreased and you full blown have the disease, the antibodies decrease now)
Diagnostic testings for hiv/aids
Serology tests are used to diagnositics by testing antibodies -
this is difficult because in the chronic subclinical phase you have a shit ton of Ab’s so its hard to get a proper diagnosis (not very reliable)
when would you get a false negative or a false positive when testing for hiv/aids
false negative: during window period - the infected person can transmit to a bunch of people without being known
False positive: cross reaction -making a bunch of ab’s against other shit that reacts with the proteins in the serological test
whats a for sure way to diagnosis hiv/aids
PCP, virus tests, and signs and symptoms
Whats an hiv virus test?
a viral antigen test: detects the presence of viral protiens
and PCR test (nucleic acids)- amplify and detects the HIV genome sequence
Describe the mother and new-born transmission
its rare -
could occur through, blood, breastmilk and placenta
usally happens because of the birth process
reduce infection: 1 dose of anti hiv before birth, and to baby 72 hours after birth
Whats the structure of HIV?
nucleic acid genome, with rna
diploid
has enzymes (reverse transcriptase, integrase, protease), with a protien coat, enveloped, gp120 attachment protiens
How does the flow of information work in HIV viruses?
its completely different then normal ‘ it bends all the rules;
the reverse transcriptase takes RNA and transcribes it to DNA ! - thats how it can be read by the hosts - it (tricks it)
HAART stands for:
highly active anti-retroviral therapy
anti hiv therapy usually involves one and one only drug TRue of FALSE?
false bitches,
- it is a combo therapy usually
involves the use of two reverse transcriptase inhibitors and one protease inhibitors
-comptetive and non competitive drugs
is AZT competitive or non competitive
Competitive inhibitor for HIV replication
How does AZT work?
targets phosphodiester bonds -
AZT is the same as thymidine but instead of hydroxide has n3 which prevents phosphate from making the phosphodiester bonds
-the viral reverse transcriptase is 100x more susceptible to the inhibition by AZT then the dna polymerase
AZT is best
what is a 3tc nucleotide like competitive RT inhibitor
hep b is also a retrovirus so works for that too -
it structured the same as thymide but instead of hydroxide, its sulfur
-competitive inhibitor cause its similar to the nucleotide
What is nevirapine?
an aids drug that is non competitive TY inhibitor
- good blocker for mother and child transmission
combo therapy with AZT, resistant mutations not likely to be at multiple sites
-Therapeutic index : >10,000 = used on babies, its safe and works at low concentrations
What is protease inhibitor?
protease inhibitors are substrate analogs - stick enzymes with something other then the actual substrate ( binds to it and stops it form cutting itself out of cell and spreading the virus) - aka inhibiting HIV
what are we expecting with HAART?
increased level of t helper cells (500/microL)
viral load decreases and u cant infect others
infectivity- full adherence to drug
describe efficacy and effectiveness in medical treatment
efficacy: what you get in a lab under close and indeal circumstances
effectiveness: real life mofo
what is the major target for HIV to get into cells?
T helper cells - they do this by gp120 binding to the t cells
How else besides gp120 does HIV enter the cell?
chemokine receptor CCR5 is necessary
Describe why having a mutation in the CCR5 receptor is a good thing
cuz its a way that HIV gets into the cell- so if you have a mutated or fucked up CCR5, it can never get in! - blessing in disguise!
What does CMV cause in people with aids?
blindness x(
