Medical Research

Watch out, little white lab mouse. Barnyard animals are gunning for your job. A bullish group of agricultural scientists says that farm animals have been vastly underrated as a resource for improving human health -- and they're vying for some of the billions of dollars the government invests in biomedical research. The human-sized hearts and blood vessels of pigs are well-suited for the study of cardiovascular disease, they say.

An implantable device that shocks an erratically beating heart and works to keep both ventricles beating synchronously reduced hospitalizations for heart failure by 41%, according to results reported Tuesday at the European Society of Cardiology Congress in Barcelona, Spain. The results, reported online in the New England Journal of Medicine, were significantly better than preliminary results announced in June, when the trial was halted prematurely because of its success. "This is a real breakthrough" for patients with mild to moderate heart disease, said Dr. Leslie Saxon, a cardiologist at USC's Keck School of Medicine, one of the study sites.

Only hours after HIV vaccine researchers announced the achievement of a milestone that has eluded them for a quarter of a century, they began plotting their next steps -- and coming to grips with a sobering reality. Their ultimate goal, halting the spread of AIDS, remains far in the future. A Thai and American team had announced early Thursday in Bangkok that they had found a combination of vaccines that provided modest protection against infection with HIV, offering the first proof of principle that the deadly disease could be tamed by teaching the immune system to recognize the virus and defeat it. Scientists around the world hailed the achievement.

A world away from the roadside bombs and combat injuries of Iraq and Afghanistan, Americans are suffering the same type of brain injury seen in troops coming home from those war-torn countries. On American roads, at workplaces and on playing fields, more than 11 million have been hurt since the fighting overseas started. Almost 1 in 5 of these civilians will struggle with lingering, often subtle symptoms -- headaches, dizziness, concentration difficulties and personality changes -- for a year, and often longer.

John Duran was a young lawyer living in West Hollywood in 1984 when he joined what would become one of the nation's longest-running studies of HIV/AIDS. "They were going to try to figure out what this thing was that was killing gay men," Duran said. More than a thousand men signed up for the Los Angeles Men's Study, part of the Multicenter AIDS Cohort Study, or MACS, that also included 5,000 men in Chicago, Baltimore and Pittsburgh. During the next 25 years, the study generated scores of scientific findings as the group of mostly white, openly gay volunteers tested HIV-positive and sought treatment.

When couples with fertility problems turn to in vitro fertilization, they often assume that they can double their chances for a healthy baby by transferring two embryos to the womb instead of just one. But data published in today's edition of the New England Journal of Medicine show that what they're really doing is increasing their odds of having twins -- which is riskier for the mother and babies alike. In the early days of in vitro fertilization, doctors routinely transferred half a dozen embryos, or more, to boost the odds that at least one would grow into a healthy fetus.

A high-fat, high-sugar diet does more than pump calories into your body. It also alters the composition of bacteria in your intestines, making it easier to gain weight and harder to lose it, research in mice suggests. And the changeover can happen in as little as 24 hours, according to a report Wednesday in the new journal Science Translational Medicine. Many factors play a role in the propensity to gain weight, including genetics, physical activity and the environment, as well as food choices.

Doctors thought that combining two newer drugs, Erbitux and Avastin, that more precisely attack cancer would help people with advanced colon cancer. Instead, it made the disease worse and made the patients more miserable, a study found. "This will stand out as a warning," said Dr. Cornelis Punt, the study's leader. "You have to do the randomized studies to see what really happens." The study was published in Thursday's New England Journal of Medicine.

Scientists proposed a new theory Wednesday of how Alzheimer's disease kills brain cells, suggesting that a chemical mechanism responsible for naturally pruning away unwanted cells during early brain development somehow gets hijacked. Amyloid precursor protein, or APP -- a key building block in brain plaques found in Alzheimer's disease -- is the driving force behind the process, said Marc Tessier-Lavigne, executive vice president of research drug discovery at Genentech. His study appears in the journal Nature.

Drugs and heart-bypass surgery protected patients better than artery-opening angioplasty and stents, according to two studies published online Wednesday in the New England Journal of Medicine. In one of the studies, bypass surgery kept people alive as well as angioplasty with less risk that the artery would clog again. In the second, researchers found patients treated after a heart attack survived longer on drugs while their care cost $7,000 less than for those given angioplasties.