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AIDS & HIV

New York City's Public Health Department today issued a public health advisory after reporting the first documented case of an alarming, new, rapidly-progressing and highly drug resistant strain of HIV in a New York man who progressed from his initial HIV infection, thought to have occurred in mid-October 2004, to a largely untreatable strain of AIDS in just three months.

Molecular & Cell Biology

A team of scientists led by Peer Bork, Ph.D., Senior Bioinformatics Scientist at the European Molecular Biology Laboratory, report today in the journal Genome Research that they have identified a new primate-specific gene family that spans about 10% of human chromosome 2. Comprised of eight family members, the RGP gene cluster may help to explain what sets apart humans and other primates from the rest of the animal kingdom.

Molecular & Cell Biology

Molecular motors harness the energy of ATP (or GTP, a related energy currency) and transform it into mechanical force. Well-known examples of motors include myosin and dynein, proteins that use ATP to ferry intracellular cargo along fibers made of actin or tubulin proteins. The ATP-dependent assembly of actin or tubulin fibers itself can work as a motor: for instance, the march of white blood cells toward pathogens is powered by the growth of actin filaments pushing against the cells’ membranes. In all cases, coherent motion implies a coordinated and polarized use of energy.

Now, Julia Cox, Oleg Tsodikov, and Michael Cox present evidence indicating that filaments of the bacterial RecA protein, long known for their role in homologous recombination and DNA repair, have properties reminiscent of a molecular motor as well. RecA filaments consist of DNA helices lined with RecA protein. RecA filaments invade a region of double-stranded DNA with similar nucleotide sequence, displacing one strand to pair with the other. Strand invasion can lead to a re-assortment—known as recombination—of DNA regions on either side of the shared sequence. It can also initiate the repair of DNA lesions during replication—the process by which a DNA molecule is copied to make two.

Stem Cell Research

Measuring the quantity of a certain type of immune cell DNA in the blood could help physicians predict whether a bone marrow stem cell transplant will successfully restore a population of infection-fighting cells called T lymphocytes in a child. This research, by investigators at St. Jude Children's Research Hospital, is published in the journal Blood.

This finding could help physicians predict whether children receiving such a transplant will experience either failure or significant delay in the reconstitution of the T cell population. Moreover, if the transplant is successful, T cells arising from donated stem cells will be available to launch attacks on the patient's cancer cells--the so-called "graft-versus-tumor" response. This will further improve the patient's outcome following initial therapy (chemotherapy, irradiation and surgery).

Biotechnology

Camouflaging an impotent AIDS virus in new clothes enables it to hunt down metastasized melanoma cells in living mice, reports a UCLA AIDS Institute study in the Feb. 13 online edition of Nature Medicine. The scientists added the protein that makes fireflies glow to the virus in order to track its journey from the bloodstream to new tumors in the animals' lungs.

"For the past 20 years, gene therapy has been hampered by the lack of a good carrier for therapeutic genes that can travel through the blood and aim itself at a precise location, thereby minimizing harmful side effects," explained Irvin S.Y. Chen, Ph.D., director of the UCLA AIDS Institute. "Our approach proves that it is possible to develop an effective carrier and reprogram it to target specific cells in the body."

The UCLA team employed a two-step approach to transform HIV into a cancer-seeking machine. First, the scientists used a version of HIV from which the viral pieces that cause AIDS had been removed. This allowed the virus to infect cells and spread throughout the body without provoking disease.

Health & Medicine

A team of researchers at the University of Bristol is developing a revolutionary new test to detect breast cancer at an early stage. If successful, this test will be effective for women of all ages; given that breast cancer is the largest killer of women between the ages of 35-55 in Europe, the test could have a dramatic effect on the number of deaths from this disease.

The test, which utilises an innovative radar system, will enable women to be tested regularly without the fear of over-exposure to radiation, a problem with existing X-ray tests. Currently, in order to detect cancer at an early stage – which is extremely important for successful treatment - many women are dependent on self-examination which can prove unreliable. This latest technology has the ability to image through dense breast tissue, and therefore can reach a far wider section of women than X-ray mammography can.