COMM 122 1st EditionExam # 3 Study Guide Lectures: 22-27Lecture 22 (March 30)1. What does Peter Duesberg propose is the major cause of AIDS?He proposed hypothesis that the various American and European diseases identified as AIDS are brought on by the long-term consumption of recreational drugs and/or AZT (life style is causing AIDS)2. What is Kaposi’s Sarcoma?Kaposi's Sarcoma (KS): rare form of relatively benign cancer that tends to occur in older people - March 1981: 8 cases of aggressive KS occurred amongst young gay men in New York- Increase in # of cases of a rare lung infection Pneumocystis carinii pneumonia (PCP) in CA & NY3. What lead to the current HIV Epidemic?- Travel- The Blood Industry- Injected Drug Use- Unprotected SexLecture 23 (April 1)1. What type of virus is HIV?HIV is a lentivirus (slow) – all attack immune system2. How are cell types infected by HIV?Cell Types Infected by HIV:- Innate immune system recognizes a pathogen and turns on a pathogen: If it doesn’t have CD-4+ marker on the outside, it can’t infect ito Can also be CCR5, CXCR4- These cells have 3 receptors in common (CD4, CCR5, and CXCR4). HIV uses these 3 receptors to enter hosts, therefore HIV can infect all 4 of these cell types3. What is HIV Pathogenesis and how does it work?HIV Pathogenesis: like to alert the body that there is an invader—HIV infects your immune cellsso it helps establish an infection inside of the lymphatic tissue due to the alert signal - If you are infected with the virus, your immune system has an immune response—body responds to the HIV and starts killing it- Your body has a hard time clearing HIV—not easy to destroy immune cells, not HPVo Destruction of the immune system occurs4. What causes Syncytia?When HIV has infected CD4+ cells bind to uninfected CD4+ causing fusion of the cellsLecture 24 (April 4)1. What is the Western Blot? The Western Blot is the Confirmatory test that looks for specific HIV proteins in a patient’s blood2. How does HIV binding occur?HIV binding to CD4+ T-cell- Gp120-CD4 binding- Conformation change which pulls the virus closer- Gp120-CD4 BIND (CCR5/cCXCR4)— they are exposed to HIV, but do not develop infection - GP41 membrane: penetration—inserts itself into your membrane (causes fusion of the HIV virus and the target cell)- Membrane fusionEnvelope virus: when two plasma membranes meet together, they fuse3. What drugs target what?- Vicriviroc: targets CCR5- Fuzeon (enfuvirtide): targets gp41- Ibalizumab: targets CD4- Selzentry (maraviroc): targets CCR5 4. How does HIV develop resistance to drugs? Eventually you get enough mutations in each of these mutations that it becomes resistant (knocksout the different categories of drugs)—mutations change the proteins enough that the proteins no longer have an effect (downward trend)5. Different outcomes for the ELISA test?False Negatives: happen if a patient has HIV, but there is no color change (Rare)- This is because there is not enough antibody in the sample- Old test kit=bad HIV antigenFalse Positives: happen if a patient does not have HIV, but there is a color change- This is because there is not enough washingLecture 25 (April 6)1. What is the set point?Set point: the point at which antibodies have been produced and the body begins to fight infection- Body is knocking down the virus - If the viral load is really high at the time (progression to AIDS is much faster)- If the viral load is really low at the time (progression to AIDS is much slower)2. What is the relation between viral load and progression to AIDS?Viral Load and Progression to AIDS: relation between baseline viral load and median survival time - If your CD4+ T-cell count is HIGH and your viral load is LOW, your medicines ARE doing a good job of controlling the virus- If your CD4+ T-cell count is LOW and you viral load is HIGH, your medicines are NOT doing a good job of controlling the virus- If you have a really high number of molecules of HIV at set point, the median life expectancy is only about 3.5 years 3. What are Opportunistic Infections? Opportunistic Infections: caused by bacteria, viruses, and other microbes that a healthy immune system would normally be capable of fighting - What you contract can be predicted by your CD4 count- If you have an outbreak of thrush, they can conclude that your T-cell counts are below 200 4. Describe the virus cycle between Malnutrition and AIDS- Poor nutrition: resulting in weight loss, muscle wasting, weakness, nutrient deficiencies- Impaired immune system: poor ability to fight HIV and other infections, increased oxidative stress- Increased vulnerability to infections: enteric infections, flu, TB hence, increased HIV replication, Hastened disease progression increased morbidity - Increased Nutritional needs: reduced food intake and increased loss of nutrientsLecture 26 (April 8)1. What are the four bodily fluids in which HIV is present?HIV is present in semen, vaginal fluid, blood, and breast milk2. How does HIV enter the Body?- Doesn’t have to have a tear: it can get on a thin layer of skin with blood vessels—the HIVcan move around those cells and into the bloodstream—The HIV virus can penetrate the outer surface of fragile skin (rectal or vaginal lining)—then the virus enters the bloodstream- The HIV virus can enter the body through a cut, sore, or needle puncture—then the virus enters the bloodstream3. Effects of alcohol and drug use?- Alcohol use is associated with high-risk sexual behaviors and IV drug use, two major modes of HIV transmission o “Nobody really pays attention to the fact that alcohol really has a higher odds ratio for being a risk factor for transmission of HIV”- Drugs lower your inhibitions—you are then more likely to do things that you wouldn’t normally do - In young people it has shown that alcohol and drug use are associated to HIVLecture 27 (April 10)1. What are HAART combinations? Highly Active Antiretroviral Therapy (HAART) is used to describe a combination of three or more anti-HIV drugs- The first HAART treatments, in 1996, included a protease inhibitor along with two nucleoside analog drugs to fight HIV—Now HAART means any potent combination of three or more anti-HIV drugs- The most commons combination of drugs used in HAART today includes 2 NRTIs with 1NNRTI or PI2. What are Entry and fusion inhibitors? Entry and fusion inhibitors (FI) interfere with the virus' ability to fuse with the cellular membrane, thereby
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