FIRST AIDS DNA VACCINE CLINICAL TRIAL
National Institute of Allergy and Infectious Diseases researchers at the Dale and Betty Bumpers Vaccine Research Center announced the start of a clinical trial testing the first AIDS vaccine. "To have taken this vaccine from concept to clinical-grade product in such a short time is an extraordinary accomplishment," comments Anthony S. Fauci, M.D., director of the NIAID. Whereas traditional vaccines usually contain a weakened or killed form of a disease-causing agent or its proteins, as their name implies, DNA vaccines contain only portions of the genetic material. The new vaccine contains the DNA blueprint for two pieces of HIV called "gag" and "pol." Gag is HIV's core protein. Pol includes three enzymes crucial for HIV replication, all of which have been modified for the vaccine to render them nonfunctional. Gag and pol remain relatively constant across different HIV strains, and together they make up about half of HIV's total protein. Once inside the body, the DNA in the vaccine instructs certain cells to make small amounts of these HIV proteins. The Phase I study is to determine if the vaccine is safe and if the body makes an immune response to these proteins. Because the vaccine does not contain genetic material for the whole virus, it is impossible for someone to become infected with HIV or to develop AIDS from the vaccine, says Fauci.
'HELPER T CELL' HELPS IMMUNITY
Harnessing the power of the body's own immune system to attack cancers may be more complex than first thought, the BBC reports. Normally, cancer cells can fool the immune system into disregarding them until it is much too late, but doctors think that it can be "reprogrammed" to launch a fierce attack on tumors. However, the new work suggests that researchers may have over-looked a type of cell that would play a vital role in this process. It was thought that the immune system response was controlled by two types of cell -- the dendritic cell and the "killer T cell." As its name suggests, the killer T cell is the one which attacks the enemy -- but the dendritic cell is thought to identify which cells are the enemy -- and which are not. It does this by picking up fragments of these cells and passing them to the killer T cells. It is widely believed that when dendritic cells are fully mature, they activate the killer T cells to launch attacks. When they are immature, they are thought to have the opposite effect. However, researchers from Rockefeller University suggest the real picture might be more complicated. They say that another type of cell, called the "helper T cell" is important in either activating the killer cells, or "tolerizing" them so they don't launch an attack.
STUDY: EARLY PREGNANCY TESTING OFF BY 10 PERCENT
Commercially available pregnancy test kits may not be accurate on the first day or so after a missed period because of natural variability in ovulation, according to researchers at the University of North Carolina. Ten percent of pregnancies in an original group of 221 women were undetectable that day even when an especially sensitive method was used. The study shows that 10 percent of the embryo attachments -- and hence new pregnancies -- had not occurred by the day women expected their periods to begin. The findings appear in the Oct. 10 issue of the Journal of the American Medical Association. By analyzing daily urine specimens throughout the earliest part of pregnancy, the researchers were able to pinpoint the day of implantation, or the day the fertilized egg attaches itself to the lining of the mother's uterus. Attachment occurs roughly nine days after fertilization, but ranges from six to 12 days. Pregnancy cannot be detected before implantation. These findings mean is that if women were to buy a test kit, follow the directions and test themselves on the first day of their expected periods, the test would be negative for many women, and they would not know that they'd become pregnant.
AMERICANS DEPRESSED YET PATRIOTIC
Americans are still suffering psychologically from last month's terrorist attacks, according to a special survey by the University of Michigan Institute for Social Research which says more than at least 66 percent have some trouble concentrating. The nationally representative sample of 668 American adults who were surveyed between Sept. 15 and Oct. 7. reported at least some trouble concentrating. Fifty-two percent said they felt depressed, and nearly 62 percent reported restless sleep at least some of the time in the last week. Only 21 percent said they often felt hopeful about the future. However, the Sept. 11 attacks have also had some positive effects on the American psyche, according to the researchers. It contributed to a sense of cohesion among the U.S. public, and more than 90 percent of those surveyed agree or strongly agree that they are proud to be an American. At the same time, the public has shifted its attitudes toward the diverse groups that make up the country, with a greater tendency to view Americans of different races, ethnicities and religions more favorably than in the past. "These results, which indicate more positive feelings about the diverse racial and ethnic groups in America, suggest that the events of Sept. 11 may have produced a more expansive sense of who is an American," says James S. Jackson. "Although Muslim Americans and Arab Americans did not fare as well, 43 percent of respondents rated these groups favorably."
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