Thursday, Nov. 12, 2009

Alzheimer's research goes against past beliefs

Doctors have long believed that too much of a substance in the brain known as beta amyloid protein can lead to the development of Alzheimer's disease.

But now in a stunning finding, researchers at St. Louis University say too little of the stuff can cause learning problems and forgetfulness as well. The discovery could lead to better Alzheimer's drugs, said Dr. John Morley.

"After 20 years of research, what we found goes totally against long-standing beliefs about amyloid beta protein," said Morley, the director of the school's division of geriatrics and the study's lead researcher.

"Our results indicate that amyloid beta protein itself isn't the bad guy. The right amount of amyloid beta protein happens to be very important for memory and learning in those who are healthy."

Researchers found that young, healthy mice that received low doses of amyloid beta protein showed improvement in recognizing objects and successfully navigating through a maze. Conversely, mice that received a drug that blocked the substance had learning impairment.

"In treating Alzheimer's disease, we have to be careful not to lower amyloid beta too much because it will cause as many problems as if you had an excess," Morley said.

The findings were published in a recent electronic issue of the Journal of Alzheimer's Disease.

Targeting cervical cancer

Researchers at Washington University in St. Louis have shown that highly targeted radiation therapy improves survival and lessens complications in cervical cancer patients.

The technique, called intensity-modulated radiation therapy (IMRT), is widely accepted for treating many cancers of the pelvic region, head and neck, and central nervous system. This is the first large study to show its effectiveness as a primary therapy for cervical cancer.

The studied followed 452 patients with newly diagnosed cervical cancer who were treated with external-beam radiation therapy. From June 1997 to March 2005, 317 received traditional whole-pelvic external-beam radiation. From March 2005 to September 2008, 137 received IMRT, which allows the radiation dose to more closely conform to the shape of the tumor.

At the most recent follow-up, 67 percent of IMRT patients were alive with no evidence of disease compared to 49 of those undergoing traditional treatment. At the same time, fewer than 4 percent of IMRT patients had died compared to 37 percent of the other group.

In addition, only 6 percent of the IMRT had developed serious bowel or bladder complications, significantly fewer than the 17 percent of those receiving traditional treatment. Researchers said all of the results are considered statistically significant even though the follow-up time of IMRT patients was much shorter.

Dr. Elizabeth Kidd, the lead author, said the size of the study and strength of the data should make it easier for patients to receive insurance coverage for IMRT treatment for cervical cancer.

Eyelash restoration

For cancer patients who undergo chemotherapy, hair loss can be one of the most distressing parts of treatment.

Now, researchers at St. Louis University are testing an approved drug to see whether they can stimulate eyelash growth in those who have lost lashes during cancer treatment.

Though hair loss is reversible after chemotherapy, eyelashes may take longer to regrow because they have a relatively short growth phase and a long resting phase. The researchers will be using the drug Latisse, which is already approved for cosmetic use to grow eyelashes longer and darker.

"After chemotherapy, people who have lost hair on their head have the option to wear a wig or a hat," said Dr. Dee Anna Glaser, the study's lead investigator. "There's nothing, right now, that they can do for eyelashes that have fallen out. We hope that this drug may be able to get patients back into normal life, feeling good about themselves and their appearance."

The study is open to those who have completed chemotherapy for early stage breast cancer, colorectal cancer or lymphoma over the past four to 12 weeks. For complete information, call 314-256-3436.

Interferon & pancreatic cancer

A team of surgeons and oncologists at the Siteman Cancer Center in St. Louis is aggressively tackling pancreatic cancer and conducting clinical trials of innovative treatment regimens.

"The perception of a lot of people is that once you get a diagnosis of pancreatic cancer, there's not much that can be done, but that's not true," said Dr. David Linehan, a pancreatic cancer surgeon.

"We're attacking this very difficult disease from multiple angles -- it's a team effort. One of our areas of focus is ways to manipulate the immune system so that it can fight the tumor."

Their latest clinical endeavor has yielded promising results by adding interferon to chemotherapy and radiation in patients who had pancreatic tumors surgically removed. In a study recently published in the Annals of Surgery, the team reported that 41 percent of these patients were alive after three years compared to a typical survival rate of 30 percent.

The team now plans a second trial using interferon in an effort to reduce side effects from the drug, which stimulates the immune system.

New test for autism?

Researchers at the University of Missouri in Columbia say they have developed a pupil response test that is 92.5 percent accurate in separating children with autism from those with typical development.

In the study, scientists used a computerized binocular infrared device, which eye doctors normally use for vision tests, to measure how pupils reacted to a 100-millisecond flash of light. The results showed that pupils of children with autism were significantly slower to respond than those of a control group.

"There are several potential mechanisms currently under study," said Gang Yao, an associate professor of biological engineering. "If these results are successfully validated in a larger population, (pupil) response might be developed into a biomarker that could have clinical implications in early screening for autism. Studies have show that early intervention will improve these children's developmental outcome."