Term
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Definition
- Viruses that carry their genetic material in the form of RNA - Have reverse transcriptase which allows transcription of RNA to DNA |
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Term
What are some subfamilies of retroviruses? |
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Definition
- Oncoviruses (HTLV-1, HTLV-2) - Lentiviruses (HIV-1, HIV-2) |
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Term
HIV is a ___, AIDS is a _____ diagnosis. |
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Definition
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Term
Who is considered as having AIDS? |
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Definition
people who are HIV positive and have less than 200 CD4 cells, or have an AIDS indicator disease |
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Term
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Definition
- enveloped - positive-strand RNA virus - encodes reverse transcriptase |
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Term
Retroviruses replicate through a ___ ___. |
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Definition
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Term
A retrovirus' DNA copy is integrated into the __ ___ to become a cellular gene |
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Definition
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Term
Gallo and Montagnier discovered which retrovirus in 1981? (duh) |
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Definition
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Term
How many people are living with HIV? |
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Definition
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Term
How many people with HIV die each year? |
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Definition
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Term
How many new infections of HIV occur per year? What about in children? |
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Definition
7 million 580,000 in children |
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Term
Two-third of world HIV infections occur in _____ |
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Definition
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Term
1 out of ____ sexually active adults in the world have HIV |
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Definition
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Term
The prevalence of HIV is highest in which group? |
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Definition
Men who have sex with men |
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Term
How can HIV be transmitted? (how likely is it for each way) |
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Definition
- blood (or fluids contaminated by blood and serum) --> 99% chance you'll get it - Semen - vaginal fluids - oral sex (but it is difficult for it to be transmitted this way) |
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Term
What host related factors increase infectiousness? |
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Definition
primary infection (highest risk due to peak in viral load) late infection genital tract infections ulcers |
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Term
What is the risk probability of transmitting HIV from a needle stick? |
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Definition
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Term
What is the risk probability of transmitting HIV from mother to infant? |
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Definition
1 in 4, or 1 in 25 with treatment |
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Term
Describe how HIV initiates replication |
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Definition
- gp120 of HIV interacts with the CD4 surface molecule expressed on T helper lymphocytes - this leads to fusion of the viral membrane and the cell membrane and viral genetic material enters in the host cell |
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Term
Once HIV releases its genetic material in the T cells, what happens?! |
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Definition
- reverse transcriptase synthesizes a complementary DNA strand - then, a copy of the DNA strand is produced - it becomes integrated into our genome by integrase |
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Term
Once the retroviruses DNA copy gets integrated into our genome what happens? |
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Definition
- viral DNA is transcribed like other host genes - each copy contains approx. five error or mutation |
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Term
Why does it matter that viruses have sloppy polymerase? |
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Definition
When there's a bunch of mutations going on, the virus may be changed such that drugs normally used to treat the virus can no longer bind. The virus may become resistant... solution is to use a cocktail of drugs |
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Term
What effect does HIV have on CD4 lymphocytes? |
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Definition
It results in cell death by direct effect or by triggering apoptosis |
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Term
Antibodies against p120 may produce ___ ___ ___ |
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Definition
antibody dependent cytotoxicity |
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Term
CD4s are primarily responsible for which areas of the immune response? |
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Definition
delayed type hypersensitivity cell mediated immunity |
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Term
Why are people with HIV at higher risk of opportunistic infection and malignancies? |
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Definition
CD4 cells also help B cells... defect in B cells BAD |
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Term
When does the peak of HIV in blood occur? |
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Definition
around 6 weeks after clinical latency it increases until death (6 to 10 years) |
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Term
What is the trend of CD4 T cell count with HIV? |
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Definition
steep decline from 0-6 weeks, increase from 6 to 12 weeks followed by a slow decline until death at 11 years |
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Term
Describe the trend of antibody against HIV |
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Definition
rises slowly until about 1 year then decreases until 8.5 years (before death) |
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Term
List some opportunistic infections characteristic of AIDS |
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Definition
-Oral candidas -Toxoplasmosis -Cryptococcal meningitis -Severe herpes -Cytomegalovirus -TB -Pneumocystis pneumonia |
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Term
What are some malignancies associated with AIDS? |
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Definition
Kaposi's sarcoma Lymphoma Cervical cancer |
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Term
What are other clinical syndromes associated with AIDS? |
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Definition
AIDS related dementia wasting syndrome |
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Term
Above 400 CD4/mm^3, what develops? |
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Definition
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Term
At 400 CD4/mm^3, what develops? |
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Definition
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Term
Below 200 CD4/mm^3, what develops? |
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Definition
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Term
Describe serology test for HIV |
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Definition
- It involves a screening test for antibodies to a number of viral antigens by enzyme immunoassay - Confirmation is done using a western blot |
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Term
Briefly explain a western blot |
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Definition
- you use an antibody to detect a protein... so wherever there is a protein, antibody will bind to it
- you run it on a gel because that separates the proteins by either structure or length of the polypeptide - then you stain it with antibody specific to the target protein |
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Term
What type of immunologic studies are used in the lab to detect, stage or monitor HIV? |
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Definition
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Term
What other lab aspects are used to examine HIV? |
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Definition
- Viral load testing - Resistance genotyping (to see if sequences of genes in HIV have mutations that cause resistance) |
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Term
Hi . If you are reading this please go look at slide 17 of the HIV lecture. |
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Definition
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Term
What are important points to touch on in pre/post test HIV counselling? |
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Definition
- What is HIV - how it's spread - pros and cons of being tested - how the test is done - explain accuracy of the test (false positives) - how results will be obtained - meaning of a positive result |
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Term
Name some anti-retrovirals. (It'll be so fun!! woo) |
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Definition
- Nucleoside analogs (reverse transcriptase inhibitors) - Non-nucleoside reverse transcriptase inhibitors - Protease inhibitors - Fusion inhibitrs - Integrase inhibitors |
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Term
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Definition
highly active anti retroviral therapy |
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Term
What are some problems with the treatment of HIV/AIDS? |
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Definition
-Side effects -Compliance -Resistance -Cost |
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Term
When should you start therapy for HIV/AIDS? |
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Definition
Controversy!! - Some say early on so that high viral loads aren't achieved... avoid transmission - Some say only when patient is socially, emotionally stable to avoid issues such as cost and compliance |
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Term
Why did the rate of HIV disease decline significantly since 1996? |
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Definition
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Term
The mortality rate associated with HIV is similar to that of ___ or __ |
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Definition
chronic liver disease or diabetes |
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Term
The risk of infection upon needle stick exposure depends on: |
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Definition
The stage of the patient's disease --> viral load How much blood --> hollow vs solid needle, gauge of the needle and was it aspiration vs. injection |
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Term
What should you do if you've have a needle stick? |
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Definition
-Confirm the patient's HIV status -Document your status (with occupational health) -Begin antiviral prophylaxis |
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Term
Who might be considered for pre-exposure prophylaxis? |
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Definition
- MSM with high risk sexual activity - Heterosexuals with multiple partners in areas of high HIV risk - partners of people with HIV (who have high viral loads) - IVDU |
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Term
What is the prophylaxis drug called? |
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Definition
Tenofovir + emtricitabine
Tuvada |
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