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34 Cards in this Set
- Front
- Back
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what is the specific type of virus that HIV is?
how many types and what are they? |
Retrovirus family (Lentivirus)
ss RNA 2 types: HIV-1 and HIV-2 |
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generally, what does HIV lead to with regards to immune system?
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PROGRESSIVE loss of immune function
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what receptors does HIV target?
On what cells? |
CCR5 (R5)
CXCR4 (X4) on T-helper cells (CD 4) |
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in what four places is there an increase in HIV cases lately?
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1. Sub-saharan africa
2. Eastern China 3. Pacific Rim 4. Eastern Europe |
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what are the three main modes of HIV transmission?
Which is primary? |
1. Sexual contact (vaginal and anal)
2. Blood borne (needle or transfusion) 3. Vertical transmission (delivery or breastfeeding) sexual contact is primary |
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what is so unique about the oral cavity?
Does this make it easier or more difficult for HIV to be transmitted there? |
it has many defense mechanisms:
salivary proteins, antibodies, SLPI, Mucins, Defensins, LL37,Thrombospondin Also has many tight jxns and desmosomes this makes it more difficult to transmit in oral cavity unless the mucosa is breached |
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what two categories of receptors does HIV interact with?
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1. CD4
2. Chemokine receptors CCR5 and CXCR4 |
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does every cell in everyone have the same amount of CCR5 and CXCR4 receptors?
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NO
this is why there is such variation between people of different races/regions |
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what is ultimately incorporated into an HIV infected cell's genome?
what makes this? what is it called when it's incorporated |
c- DNA
Reverse Transcriptase HIV Provirus |
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what does the HIV virus do to T-cells for optimal replication?
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downregulates them
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Why is a vaccine against HIV very difficult to develop?
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B/c reverse transcriptase is very ERROR PRONE, making a mistake once in every 2000 bases.
This makes for a constantly changing genome and the development of new and resistant strains all the time |
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what must successful HIV vaccines be able to account for?
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the high error rate of reverse transcriptase
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What three methods are used to diagnose HIV?
how long after exposure will it work? |
1. ELISA
2. Western Blot 3. Oral Kit for HIV Ig's in saliva 10-14 days |
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what are the six major stages of HIV infection and the approx time tables for each?
What does HAART do to these stages? |
1. Initial Transmission stage
2. Acute Retroviral Syndrome (2-3 weeks) 3. Recovery and seroconversion (within 6 weeks) 4. Asymptomatic chronic HIV stage 5. Symptomatic infection 6. AIDS (1-2 years prior to death) Prolongs length of the stages prolonging death |
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what are teh three CDC AIDS surveillence definitions?
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1. "A" - Acute HIV infection, asymptomatic disease, or persistent lymphadenopathy
2. "B" - Symptomatic disease including Oropharyngeal candidiasis, or OHL 3. "C" - 26 AIDS indicator conditions including: Pneumocystis carinii, wasting, candidiasis of esophagus, trachea, bronchi, or lungs. TB, KS, CMV, TA, dementia. |
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what two major numbers do lab tests give regarding HIV?
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1. CD-4 count
2. Viral loads (viremia) |
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what type of relationship is there between viremia and T-cell counts?
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INVERSE
makes sense because as virus spreads, more t-cells are knocked out and they decrease |
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which type of HIV (CCR5 or CXCR4) is more aggressive and more detrimental?
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CXCR4
(bc it has the "X"-factor) |
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what are the two primary goals of management of patient with HIV?
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1. Suppress HIV viremia
2. Prevent and treat opportunistic infections that result from immunosupression |
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what are the three classes of drugs used in HAART?
are there synergistic effects? |
1. Protease inhibitors (prevent release)
2. Nucleoside reverse transcriptase 3. Non-nucleoside reverse transcriptase yes, there are synergistic effects |
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What is the most popular NRT drug for HIV?
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AZT = Zidovudine
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what are the five most prevalent opportunistic infections associated with HIV?
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1. TB
2. Pneumocystis carinii 3. CMV 4. Malaria 5. Candida |
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where is HIV transmission especially likely?
Why? |
through vaginal epithelium
the layers of epithelial cells are very thin (due to progestins, laceration, and ulcers) |
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where does HIV reverse transcriptase make the c-DNA that is inserted into host cell chromosome to make HIV Provirus?
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in the cytoplasm
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is the HIV c-DNA single or double stranded?
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double -> because that's what the host cell chromosome is!
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what are the two most common late events in an HIV infected cell?
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1. Downregulation of CD-4
2. Replication of new virions |
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what does clinical staging of HIV rely on?
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CD-4 cell count
Viral load |
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look at slide for dental implications of HIV
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do it now!
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what three places in USA have highest levels of HIV?
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New York
Florida Puerto Rico |
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are US AIDS deaths increasing or decreasing?
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decreasing (by 20-40% each year)
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what condition is major predictor of HIV infection and onset of AIDS?
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Oral Candidiasis (thrush = pseudomembraneous candidiasis)
Hairy Leukoplakia |
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which HIV type is responsible for the majority of worldwide epidemic?
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HIV - 1
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what are the two major groups of HIV1?
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M variants
O variants |
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what two things can we do to help prevent transmission of HIV as dentists?
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1. always wear nitrile gloves
2. always wear masks |
