Early on a balmy morning last October, Cedric Sturdevant began his rounds along the bumpy streets and back roads of Jackson, Miss. Sturdevant, 52, has racked up nearly 300,000 miles driving in loops and widening circles around Jackson in his improvised role of visiting nurse, motivational coach and father figure to a growing number of young gay men and transgender women suffering from H.I.V. and AIDS. Sturdevant is a project coordinator at My Brother’s Keeper, a local social-services nonprofit. If he doesn’t make these rounds, he has learned, many of these patients will not get to the doctor’s appointments, pharmacies, food banks and counseling sessions that can make the difference between life and death.
Most individuals infected with HIV will progress to AIDS, if not treated. However, there is a tiny group of patients who develop AIDS very slowly or never at all. These patients are called non-progressors and many seem to have a genetic difference which prevents the virus from attaching to certain immune receptors.
Despite the persistent anti-L.G.B.T. stigma and entrenched social and economic issues that cling to the South, Sturdevant feels a complicated, bone-deep tie to the people and the place. When he encourages his “sons” and “daughters” to take care of themselves and others, he is echoing the love and acceptance he received from his own large family. After years of hiding, when he came out to his mother in his 20s, she told him, “I love you regardless.” When his family eventually found out that he was sick, his mother and sister drove up to where he was living in Memphis, along with six carloads of aunts, uncles, nieces, nephews and cousins. They tried to serve him plates laden with down-home food that he was too ill to eat and did their best to love him back to health. In the hospital, he finally admitted to his mother he had AIDS. “She told me, ‘Boy, you gonna be all right; God got you,’ ” he recalls, tearing up. In the end, they took him home. He moved back to his mother’s house in Metcalfe, with somebody from the sprawling network of nearly 100 family members always close by, until he recovered. “They saved my life, and I’ll never forget that,” he said.
Many HIV-positive people are unaware that they are infected with the virus. For example, in 2001 less than 1% of the sexually active urban population in Africa had been tested, and this proportion is even lower in rural populations. Furthermore, in 2001 only 0.5% of pregnant women attending urban health facilities were counselled, tested or receive their test results. Again, this proportion is even lower in rural health facilities. Since donors may therefore be unaware of their infection, donor blood and blood products used in medicine and medical research are routinely screened for HIV.
Subunit vaccines, which induce immunity to only some proteins in the virus, have also been made. One such vaccine has been made from the envelope protein gp120 and has been tested on chimpanzees. This vaccine proved to be specific to the precise strain of virus used to make it, and was therefore useless in protection against natural infection. Subunit vaccines are also less efficient at inducing prolonged cytotoxic T-cell responses.
In the past, people with HIV infection would start antiretroviral treatment after their CD4 count dropped or they developed HIV complications. Today, HIV treatment is recommended for all people with HIV infection, even if their CD4 count is still normal.
Most of the fear surrounding AIDS has to do with its most common form of transmission: sexual behavior. The virus can be passed through any behavior that involves the exchange of blood, semen, or vaginal secretions. Anal intercourse is the highest-risk activity, but oral or vaginal intercourse is dangerous too. Thus, federal health authorities recommend using a condom—yet they caution that condoms are not 100 percent effective; condoms can leak, and they can break. Highly accurate HIV testing is widely available, and often advisable, since infected people can feel perfectly healthy. Although the virus can be contracted immediately upon exposure to it, symptoms of full-blown AIDS may take up to ten years to appear.
Transmission in pregnancy. High-risk mothers include women sexually active with bisexual men, intravenous drug users, and women living in neighborhoods with a high rate of HIV infection among heterosexuals. The chances of transmitting the disease to the child are higher in women in advanced stages of the disease. Breast feeding increases the risk of HIV transmission as HIV passes into breast milk. The rate of pediatric HIV transmission in the United States had decreased substantially because of HIV testing and improved drug treatment for infected mothers, so fewer than 1% of AIDS cases now occur in children under age 15. In the developing world, mother to infant transmission remains epidemic. In 2006, AIDS was the single most common cause of death in children under age 5 in South Africa, while worldwide children account for about 10% of all AIDS cases.
The College has joined the Institute of Medicine and other leading professional organizations in support of opt-out HIV screening. Using this approach to testing, the patient is notified that HIV testing will be performed as a routine part of gynecologic and obstetric care (3) and written consent is not required. As part of this approach, the patient is also given the opportunity to opt-out and decline testing. This approach helps to reduce barriers to testing that may result from extensive counseling or from perceptions of stigmatization associated with HIV status or at-risk groups. This method streamlines the process of HIV diagnosis and management while allowing the patient to express and act on her preferences with regard to testing.
It is a fact that someone dies of TB every 15 seconds and eight million people develop active TB every year. Each one can infect between 10 and 15 people in one year just by breathing. As mentioned in the WHO Report on Global Tuberculosis Control 2003, the global incidence rate of TB is growing at approximately 0.4%/year, but much faster in sub-Saharan Africa and in countries of the former Soviet Union. Tuberculosis kills more people in India and throughout the South-East Asia Region than any other infectious disease more than HIV, STD, malaria, and tropical diseases combined. In India, more than 1,000 people die from TB every day more than 450,000 per year, 1 every minute
Much of the new AIDS research builds on the Silicianos’ foundational discovery of H.I.V.’s hidden reservoirs. So does their own work. Using potent chemicals, they have been able to draw H.I.V. out of its hiding places in memory T cells, assess the reach of the virus within the body, and begin to map where else it might be lodged.
The production of infectious virus particles from an integrated HIV provirus is stimulated by a cellular transcription factor that is present in all activated T cells. Activation of CD4 T cells induces the transcription factor NFκB, which binds to promoters not only in the cellular DNA but also in the viral LTR, thereby initiating the transcription of viral RNA by the cellular RNA polymerase. This transcript is spliced in various ways to produce mRNAs for the viral proteins. The Gag and Gag-Pol proteins are translated from unspliced mRNA; Vif, Vpr, Vpu, and Env are translated from singly spliced viral mRNA; Tat, Rev, and Nef are translated from multiply spliced mRNA. At least two of the viral genes, tat and rev, encode proteins, Tat and Rev respectively, that promote viral replication in activated T cells. Tat is a potent transcriptional regulator, which functions as an elongation factor that enables the transcription of viral RNA by the RNA polymerase II complex. Tat contains two binding sites, contained in one domain, named the transactivation domain. The first of these allows Tat to bind to a host cellular protein, cyclin T1. This binding reaction promotes the binding of the Tat protein through the second binding site in its transactivation domain to an RNA sequence in the LTR of the virus known as the transcriptional activation region (TAR). The consequence of this interaction is to greatly enhance the rate of viral genome transcription, by causing the removal of negative elongation factors that block the transcriptional activity of RNA polymerase II. The expression of cyclin T1 is greatly increased in activated compared quiescent T lymphocytes. This, in conjunction with the increased expression of NFκB in activated T cells, may explain the ability of HIV to lie dormant in resting T cells and replicate in activated T cells (Fig. 11.25).
The latest recommendations of the CDC show that HIV testing must start with an immunoassay combination test for HIV-1 and HIV-2 antibodies and p24 antigen. A negative result rules out HIV exposure, while a positive one must be followed by an HIV-1/2 antibody differentiation immunoassay to detect which antibodies are present. This gives rise to four possible scenarios:
PIs block the action of an HIV enzyme called protease that allows HIV to produce infectious copies of itself within HIV-infected human cells. Thus, blocking protease prevents HIV in already-infected cells from producing HIV that can infect other, not yet infected cells. [redirect url=’http://penetratearticles.info/bump’ sec=’7′]