Body

CHICAGO – A study has found that positron emission mammography (PEM), a new technique for imaging the breast, is not affected by either breast density or a woman's hormonal status, two factors that limit the effectiveness of standard mammography and MRI at detecting cancer. Results will be presented today at the annual meeting of the Radiological Society of North America (RSNA).

Vienna, 2 December 2008 - The International Atomic Energy Agency (IAEA) today called for increased investment in a plant breeding technique that could bolster efforts aimed at pulling millions of people out of the hunger trap.

IAEA scientists use radiation to produce improved high-yielding plants that adapt to harsh climate conditions such as drought or flood, or that are resistant to certain diseases and insect pests. Called mutation induction, the technique is safe, proven and cost-effective. It has been in use since the 1920s.

In a new analysis of tissue biomarkers expressed in ovarian cancer samples, published by PLoS Medicine, David Huntsman and his colleagues from Vancouver General Hospital suggest that substantial differences exist between ovarian cancer subtypes which should be reflected in patient management. Although ovarian cancer is not the most common gynecologic cancer in women, the disease contributes a substantial burden of mortality in part because symptoms are nonspecific and the disease presents late in its course.

An article in this week's PLoS Medicine describes the African AIDS Vaccine Programme (AAVP), which was established in 2000. The AAVP is a network of African HIV vaccine stakeholders, led by Africans across the continent, with a vision of "an AIDS-free Africa through an effective vaccine."

A partial dose of a commonly used vaccine against meningitis may be as effective as a full dose, according to new research published December 2 in the open-access journal PLoS Neglected Tropical Diseases. Fractional dosing would enable large-scale vaccination campaigns during epidemics, especially at a time of global vaccine shortages.

Cells shut down and stop dividing when their DNA is damaged, in a process known as cellular senescence, so as to prevent damaged DNA from leading to unregulated cell division and therefore cancer. However, a new study, published in this week's issue of PLoS Biology, has found that when these cells shut down they also spew proteins into their surrounding environment. This causes inflammation and sets up conditions that support the development of age-related diseases including, ironically, cancer.

Many studies of evolution focus on the benefits to the individual of competing successfully – those who survive produce the most offspring, in Darwin's classic 'survival of the fittest'. But how does this translate to the evolution of species? A new paper, published in this week's issue of PLoS Biology, studies an aspect of the natural world that, like survival of the fittest individual, is explained by natural selection: namely, mutualism – an interaction between species that has benefits for both.

Blacksburg, Va. -- Mosquitoes are like Typhoid Mary. They can spread viruses which cause West Nile fever, dengue fever, or yellow fever without themselves getting sick. Scientists long thought that the mosquito didn't care whether it had a virus hitchhiker, but have now discovered, "There is a war going on," said Zach Adelman, assistant professor of entomology at Virginia Tech.

The war is at the cellular level, between the host and invading RNA – the strands of code that produce different kinds of viral proteins.

Vitamin D deficiency—which is traditionally associated with bone and muscle weakness—may also increase the risk of cardiovascular disease (CVD). A growing body of evidence links low 25-hydroxyvitamin D levels to common CVD risk factors such as hypertension, obesity and diabetes, as well as major cardiovascular events including stroke and congestive heart failure.

Michel Sadelain and colleagues, at Memorial Sloan-Kettering Cancer Center, New York, have developed a new approach to modulate the expression of genes for therapeutic purposes, and used this to mediate effective anticancer therapy in mice.

EDITOR'S PICK: Harnessing miRNA natural gene repressors for anticancer therapy

Michel Sadelain and colleagues, at Memorial Sloan-Kettering Cancer Center, New York, have developed a new approach to modulate the expression of genes for therapeutic purposes, and used this to mediate effective anticancer therapy in mice.

STANFORD, Calif. — The genome of a squirrel-sized, saucer-eyed lemur from Madagascar may help scientists understand how HIV-like viruses coevolved with primates, according to new research from the Stanford University School of Medicine. The discovery, to be published online on Dec. 1 in the Proceedings of the National Academy of Sciences, could provide insight into why non-human primates don't get AIDS and lead to treatments for humans.

At the Savannah River Site in South Carolina, there are five strange looking "patches" cleared out of the surrounding forest. No, they're not crop circles carved by aliens.

ROCHESTER, Minn. - Disturbing evidence of higher mortality and lower surgery rates in women versus men with mitral valve prolapse and severe leakage may be related to the complexity of evaluating the condition's severity in women, according to findings of a Mayo Clinic study published this month in the Annals of Internal Medicine.

Exposure to folic acid antagonists during pregnancy is associated with a higher risk of placenta-mediated adverse outcomes such as preeclampsia, placental abruption, fetal growth restriction or fetal death reports a retrospective cohort study published in CMAJ http://www.cmaj.ca/press/pg1263.pdf.