Body

STANFORD, Calif. — Like a child awaiting the arrival of Christmas, embryonic stem cells exist in a state of permanent anticipation. They must balance the ability to quickly become more specialized cell types with the cellular chaos that could occur should they act too early (stop shaking those presents, kids!).

La Jolla, CA—In order to preserve our DNA, cells have developed an intricate system for monitoring and repairing DNA damage. Yet precisely how the initial damage signal is converted into a repair response remains unclear. Researchers at the Salk Institute for Biological Studies have now solved a crucial piece of the complex puzzle.

Famous for its antioxidant properties and role in tissue repair, vitamin C is touted as beneficial for illnesses ranging from the common cold to cancer and perhaps even for slowing the aging process. Now, a study published online on December 24th by Cell Press in the journal Cell Stem Cell uncovers an unexpected new role for this natural compound: facilitating the generation of embryonic-like stem cells from adult cells.

A new study establishes a molecular link that bridges two rare inherited disorders and explains why these diseases result in genetic instability. The research, published by Cell Press in the December 24th issue of the journal Molecular Cell, may lead to a better understanding of the complex mechanisms that enable cells to repair damaged DNA.

Earlier this year, researchers showed that they could cut the lives of disease-carrying mosquitoes in half by infecting them with a bacterium they took from fruit flies. Now, a new report in the December 24th issue of Cell, a Cell Press publication, suggests that their strategy might do one better: The Wolbachia bacteria also makes the mosquitoes more resistant to infection by viruses that are a growing threat to humans, including those responsible for dengue fever and Chikungunya.

UCLA scientists have identified a molecular switch that prevents Huntington's disease from developing in mice. Published in the Dec. 24 edition of the journal Neuron, the discovery suggests a new approach to treating the genetic disorder, which ultimately leads to death in as little as 10 years.

Cancer progression is commonly thought of as a process involving the growth of a primary tumor followed by metastasis, in which cancer cells leave the primary tumor and spread to distant organs. A new study by researchers at Memorial Sloan-Kettering Cancer Center shows that circulating tumor cells – cancer cells that break away from a primary tumor and disseminate to other areas of the body – can also return to and grow in their tumor of origin, a newly discovered process called "self-seeding."

In Huntington's disease, a mutated protein in the body becomes toxic to brain cells. Recent studies have demonstrated that a small region adjacent to the mutated segment plays a major role in the toxicity. Two new studies supported by the National Institutes of Health show that very slight changes to this region can eliminate signs of Huntington's disease in mice.

Researchers do not fully understand why the protein (called mutant huntingtin) is toxic, but one clue is that it accumulates in ordered clumps of fibrils, perhaps clogging up the cells' internal machinery.

STANFORD, Calif. — Genomic switches can predispose an individual to one set of autoimmune disorders but protect the same person against another set of them, scientists at Stanford University School of Medicine have found.

"Maybe we should stop considering all autoimmune diseases in one lumped category," said Atul Butte, MD, PhD, assistant professor of pediatrics and of biomedical informatics and director of the Center for Pediatric Bioinformatics at Lucile Packard Children's Hospital. "It looks as if there may be at least two different kinds."

Researchers have uncovered the complete genetic make-up of the cavity-causing bacterium Bifidobacterium dentium Bd1, revealing the genetic adaptations that allow this microorganism to live and cause decay in the human oral cavity. The study, led by Marco Ventura's Probiogenomics laboratory at the University of Parma, and Prof. Douwe van Sinderen and Dr Paul O'Toole of the Alimentary Pharmabiotic Centre at University College Cork, is published December 24 in the open-access journal PLoS Genetics.

Pediatric researchers have identified a novel gene involved in childhood asthma, in one of the largest gene studies to date of the common respiratory disease. Because the gene, called DENND1B, affects cells and signaling molecules thought to be instrumental in the immune system overreaction that occurs in asthma, the discovery may have singled out an important target for new treatments.

PORTLAND, Ore. December 23, 2009. A study recently completed in the gulf coast of Alaska by federal and university researchers has found that as glacial ice disappears, the production and export of high- quality food from glacial watersheds to marine ecosystems may disappear too. This trend could have serious consequences for marine food webs.

The study, "Glaciers as a source of ancient and labile organic matter to the marine environment," was recently published in the December 24, 2009, issue of the journal Nature.

Inhibition of transcription factor E2F1 reduced epidermal growth factor receptor (EGFR) expression and reduced the invasive potential but not proliferation of metastatic melanoma cells, according to a brief communication published online December 23 in the Journal of the National Cancer Institute.

BEER-SHEVA, ISRAEL -- December 23, 2009 -- A new study conducted at Ben-Gurion University of the Negev (BGU) reveals that Celebrex and other anti-inflammatory coxib medications may counter the positive effects of aspirin in preventing blood clots.

The research, published in the Proceedings of the National Academy of Sciences (PNAS), indicates that people who are taking aspirin and coxibs together are in fact inhibiting the aspirin's effectiveness in preventing heart attacks and strokes.

Washington, D.C. -- A new study in the journal Infection Control and Hospital Epidemiology reports a surge in drug-resistant strains of Acinetobacter, a dangerous type of bacteria that is becoming increasingly common in U.S. hospitals. This study is being posted online today and will appear in the journal's February print edition.