Hide and Seek
Video game glasses, stomach bugs and a mysterious molecule revealed.
TO STAVE OFF bacterial infection, white blood cells engulf and destroy germs with powerful digestive enzymes—a process the wily tuberculosis bacterium often manages to evade. Now researchers at the University of British Columbia and Vancouver Coastal Health Research Institute have discovered how. Mycobacterium tuberculosis secretes a protein, PtpA, that acts directly on a white-blood-cell signaling protein to keep it from sending out its “digest and destroy” message, allowing the germ to invade and multiply in the white blood cell. Researchers have already engineered an antibody that blocks the protein, which they hope will become a basis for therapy.
FORGOING HEART SURGERY to avoid the oft-reported side effect of memory lapse is an option many patients have considered. But Johns Hopkins researchers who compared the cognitive function of patients receiving surgery with that of patients who received non-surgical treatments suggest that surgery was not to blame. During six years post-treatment, both groups experienced an almost identical decline in cognitive function.
STEREOSCOPIC GLASSES, inspired by the technology that video gamers use to simulate depth perception, could become a tool for operating on a beating heart. A surgeon at Children’s Hospital Boston repaired 32 atrial septal defects in pigs using standard 3-D ultrasound guidance alone, then donned the glasses for another 32 procedures. With the depth perception the glasses provide, he was 44% faster, as reported in The Journal of Thoracic and Cardiovascular Surgery.
A MYSTERIOUS MOLECULE in the liver, called the Ashwell receptor, seems to play a crucial role in fighting infection. Researchers at the University of California, San Diego School of Medicine discovered that the receptor reduces levels of blood-coagulating factors to help the body combat the lethal blood clotting caused by sepsis. In theory, then, a drug designed to boost supply of the molecule might decrease mortality from sepsis and other blood infections.
PERIODONTAL DISEASE, already linked to heart disease and diabetes, has now been implicated in cancer. In a study by researchers at Imperial College London, subjects with a history of the gum disease had a 14% higher incidence of cancer than those without. Begun in 1986, the research included more than 48,000 males who answered questionnaires about oral hygiene every two years. Follow-up studies are needed to confirm the results and to determine whether the same holds for female subjects. But the researchers say that reducing any risk conferred by this link is as easy as flossing.
A TENACIOUS STOMACH BACTERIUM may find a beneficial use—as a carrier for the flu vaccine. Barry J. Marshall, who won a Nobel Prize for his discovery of Helicobacter pylori, infected mice with a flu-carrying form of H. pylori. The bacterium colonized the animals’ stomachs and generated antibodies to fight the flu, as reported in the journal Helicobacter. This year, in the first round of trials, Marshall plans to remove and then replace the germ in healthy subjects’ stomachs to see how their immune systems respond; if successful, he’ll test the flu-carrying form. Eventually he hopes to develop a commercial yogurtlike drink to easily administer the vaccine.