Brain

MADISON -- U.S. science and engineering students emerge from graduate school exquisitely trained to carry out research. Yet when it comes to the other major activity they'll engage in as professors – teaching – they're usually left to their own devices.

If chromosomes snuggle up too closely at the wrong times, the results can be genetic disaster.

Now researchers have found the molecular machines in fruit flies that yank chromosomes, the DNA-carrying structures, apart when necessary.

The machines, proteins called condensin II, separate chromosomes by twisting them into supercoils that kink up and therefore can no longer touch.

Scientists had known of condensin II but did not know how it functioned inside cells.

When mice that lack steroid receptor-2 (SRC-2) – a master regulator gene called a coactivator – fast for a day, their blood sugar levels plummet. If they go another day without food, they will die.

The severity of the hypoglycemia (low blood sugar) was unexpected, said Dr. Bert W. O'Malley, chair of molecular and cellular biology at Baylor College of Medicine and senior author of the report on the study that appears in the current issue of the journal Science. Normal mice live as long as seven days without food.

CORVALLIS, Ore. – In the same way that winter is commonly known to be the "flu season," a new study suggests that the dog days of summer may well be the "bacterial infection" season.

Researchers have discovered that serious infections caused by gram-negative bacteria can go up as much as 17 percent with every 10 degree increase in seasonal temperature. The findings, which were based on seven years of data from infections in a Baltimore hospital, suggest that the incidence there of some of these illnesses might be up to 46 percent higher in summer than in winter.

NEW YORK – Bone growth is controlled in the gut through serotonin, the same naturally present chemical used by the brain to influence mood, appetite and sleep, according to a new discovery from researchers at Columbia University Medical Center. Until now, the skeleton was thought to control bone growth, and serotonin was primarily known as a neurotransmitter acting in the brain. This new insight could transform how osteoporosis is treated in the future by giving doctors a way to increase bone mass, not just slow its loss. Findings are reported in the Nov. 26, 2008 issue of Cell.

As you gorge on food this holiday season, you might not want to think about the fat content of all the goodies you've indulged in. Nevertheless, your brain will be keeping tabs directly, suggests a report in the November 26th issue of the journal Cell, a Cell Press publication.

When it comes to remodeling our bones—an ongoing process of break down and renewal that goes on throughout adulthood--researchers have new evidence that our guts play a surprisingly important role. The findings point toward novel methods for increasing bone mass in patients with diseases characterized by impaired bone formation, including postmenopausal osteoporosis, according to the report in the November 26th issue of the journal Cell, a Cell Press publication.

New evidence may explain why it is that we lose not only our youthful looks, but also our youthful pattern of gene activity with age. A report in the November 26th issue of the journal Cell, a Cell Press publication, reveals that a protein perhaps best known for its role in the life-extending benefits of a low-calorie diet also maintains the stability of the mammalian genome—the complete set of genetic instructions "written" in DNA.

Genetic mouse models have provided surprising insight into mechanisms linking serotoninergic compounds with the regulation of feeding behavior and body weight. The research, published by Cell Press in the November 26th issue of the journal Neuron, pinpoints a specific group of brain cells that mediate energy balance and may lead to the development of antiobesity drugs with fewer side effects.

Johns Hopkins researchers have used fruit flies to gain new insights into a brain-damaging disorder afflicting children. Their work suggests a possible therapy for the disease, for which there is currently no treatment.

In the battle against obesity, Yale University researchers may have discovered a new weapon — a naturally occurring molecule secreted by the gut that makes rats and mice less hungry after fatty meals. The findings are published in the Nov. 26 issue of the journal Cell.

The report suggests the molecule may help regulate how much animals and people eat, according to the team headed by Gerald I. Shulman, Yale professor of medicine and cellular & molecular physiology and a Howard Hughes Medical Institute investigator.

Researchers have identified a molecule that tells your brain your stomach is full – signaling that it's time to say no to a second piece of pumpkin pie and push back from the Thanksgiving table.

CHICAGO --- Scientists peered at the brains of people with a baffling chronic pain condition and discovered something surprising. Their brains looked like an inept cable guy had changed the hookups, rewiring the areas related to emotion, pain perception and the temperature of their skin.

The new finding by scientists at Northwestern University's Feinberg School of Medicine, begins to explain a mysterious condition that the medical community had doubted was real.

Waltham, Mass.—In a novel study appearing this week in Neuron, Brandeis researchers identify for the first time a specific set of wake-promoting neurons in fruit flies that are analogous to cells in the much more complex sleep circuit in humans. The study demonstrates that in flies, as in mammals, the sleep circuit is intimately linked to the circadian clock and that the brain's strategies to govern sleep are evolutionarily ancient.

Research from the Medical Research Council (MRC) Toxicology Unit at the University of Leicester shows that nitric oxide (NO) can change the computational ability of the brain. This finding has implications for the treatment of neurodegenerative diseases such as Alzheimer's Disease and our understanding of brain function more generally.

The research is led by Professor Ian Forsythe and is reported in the journal Neuron on 26th November.