THURSDAY, Jan. 24 (HealthDay News) -- An international team of researchers has finally managed to locate stem cells in the pancreas -- in mice, at least.

If the findings are confirmed in humans, they could pave the way for dramatic new therapies for diabetes, namely the regeneration of beta cells so the body could once again produce its own insulin. Until now, scientists had all but abandoned hopes that the pancreas made its own stem cells because they had failed to find evidence to support the theory.

But any clinical advances from the new research are still a long way off, experts cautioned.

"This is the first conclusive evidence that there are stem cells in the pancreas, but any potential benefit is a very long way away," said Juan Dominguez-Bendala, director of Stem Cell Development for Translational Research at the Diabetes Research Institute of the University of Miami Miller School of Medicine.

"If this kind of cell and their progenitors with a capacity to divide exist in the pancreas of man, and if we can identify the factors that are responsible to induce their proliferation and differentiation, then these latter processes might be stimulated in vitro but also, by noninvasive means, in vivo," said senior study author Harry Heimberg, an associate professor at the Diabetes Research Center of Vrije Universiteit Brussel in Belgium.

The findings are published in the Jan. 25 issue of the journal Cell.

Diabetes is primarily a failing of the pancreatic beta cells to produce insulin. Beta cells are one of several types of cells making up clusters of cells called the islets of Langerhans.

Insulin is a hormone that moves blood sugar from the bloodstream to the cells, where it is used as energy.

In type 1 diabetes, the pancreas has lost all or virtually all of its ability to produce insulin. In type 2 diabetes, the loss of beta cells is more gradual.

Islet-cell transplantation, in which islets are transferred from one person to another, is performed today but is limited in scope because of a shortage of donors, according to the study.

The very existence of pancreatic stem cells is controversial. A recent study out of Harvard found that the major source of new beta cells in adult mice was preexisting beta cells, not stem cells. The finding reduced the urgency to track down pancreatic stem cells.

"If stem cells didn't contribute, what was the point," said Dominguez-Bendala.

For this study, Heimberg and his colleagues cut off the duct that drains digestive enzymes from the pancreas in mice. Within two weeks, the number of beta cells in the pancreas doubled.

Not only did the number of beta cells increase, the mice started producing more insulin.

"When damaged a specific way, it triggered stem cells" production, Dominguez-Bendala said.

The newly identified stem cells were almost identical to embryonic beta cell progenitors. In fact, the gene Neurogenin 3 (Ngn3), which plays a role in embryonic development of the pancreas, is also involved in the formation of these new beta cells, the researchers said.

"This is a model of regeneration no one has tested before," Dominguez-Bendala said. "From a basic science point of view, it's very exciting. It opens the door to potential therapies. If we could trigger regeneration, that would be fantastic."

"This demonstrates a stem cell repair mechanism in the pancreas that, if we understand it more, then we can help develop more cures with either transplantation or with drugs that can increase the body's own stem cells and beta cells," said Paul Sanberg, director of the University of South Florida Center for Aging and Brain Repair in Tampa.

More information

For more on pancreatic islet transplantation, visit the U.S. National Diabetes Information Clearinghouse.

SUNDAY, Feb. 3 (HealthDay News) -- Irish researchers hope to prove that a dog's keen sense of smell gives it the ability to watch over the blood sugar levels of diabetics.

Canines have already shown themselves capable of leading the blind, alerting the deaf, and helping the physically disabled with daily tasks.

But researchers at Queen's University in Belfast, Northern Ireland, are taking the "helpful companion" idea one step further by gathering scientific evidence that could verify dogs can reliably detect dangerous blood sugar level drops in diabetics.

"Anecdotal reports suggest that some dogs can perform early warning of hypoglycemia by using their sense of smell to 'sniff out' if their owner's blood sugar levels are dropping," said lead researcher and psychology professor Deborah Wells.

More than 20 million U.S. children and adults have diabetes, according to the American Diabetes Association. Those with the disease do not produce enough insulin, a hormone the body needs to convert sugars, starches and other food into energy.

Diabetics must test their blood glucose level regularly, even sometimes in the middle of the night to avoid the peaks and valleys that can cause organ failure, say experts.

Wells hopes to find out what cues dogs pick up on so they can officially be recognized and trained as early-warning systems for diabetics.

At least two organizations in the United States already train dogs to detect low glucose levels. But exactly what the canines notice when a person experiences a blood sugar low is still a mystery, said Mark Ruefenacht, founder of Dogs for Diabetics, in Concord, Calif.

The organization is working with a forensic laboratory to identify a possible odor.

"We just haven't come up with the right answers," he said. "Every time we think we have the answer, we find that we don't."

Ruefenacht, a diabetic, started the organization three years ago, inspired after a puppy he was raising for Guide Dogs for the Blind woke him one night. Ruefenacht forgot to check his blood sugar before going to sleep, and he thinks he had a seizure that alarmed the pup.

Since then, the all-volunteer group has placed 30 trained canines in the homes of Northern California residents with type 1 diabetes.

Demand for the dogs is high; more than 100 people are on the waiting list.

Dogs for Diabetics uses Labrador retrievers that don't graduate from guide dog school. These dogs usually flunk for reasons such as refusing to walk in the rain or step onto an escalator -- all skills important for being a working dog, but not a general assistance one.

Ruefenacht said his dogs undergo three to four months of training similar to what is used to prepare dog to detect narcotics or explosives. The 2-year-old canines are first taught to detect scent samples of low blood sugar. Then they learn to find that scent on people, and alert others by holding in their mouth a soft tube that hangs from around their neck.

Dogs that successfully complete training are 90 percent accurate, Ruefenacht said.

These clever canines aren't the only ones that must learn new tricks.

Mary Simon has battled diabetes for more than three decades, and she now drives four hours each week from her home in Fresno to attend the required class.

"I need this dog desperately," said Simon, a diabetic who is also medical director for the Diabetic Youth Foundation in Concord, Calif.

Medication she takes hampers her ability to feel nighttime lows, she said, and the special glucose sensor she wears doesn't always work.

When Simon first learned of the hypoglycemic detection dogs a few years ago, she didn't think their talent was needed because glucose sensors were about to hit the market. Since then, she's changed her mind.

"My own personal experience is we need [the dogs] right now," she said.

Not everyone is so quick to put their trust in the canines' ability.

Larry Myers, a veterinarian and professor at Auburn University in Alabama, has trained dogs to detect everything from drugs to agricultural pests for 25 years. He said the jury is still out on whether dogs can truly detect low blood sugar levels, but he believes it's a possibility worth exploring.

Even though dogs have amazing olfactory abilities, he said they are not universally sensitive to all chemicals.

"Do hypoglycemic individuals, in fact, emit an odor that is characteristic? I don't know, and I don't think anybody does know right now," he said.

A possibility other than scent is the dogs are picking up on visual cues, which is thought to be the case with seizure detection dogs. Such dogs allegedly can pick up on extremely subtle physiological changes in their human companion that may begin five to 45 minutes before an actual attack. The dogs then warn the humans so they can find a safe environment or take precautionary measures.

"It turns out what the dogs are really sensitive to is subtle changes in behavior of the individuals just prior to seizing," Myers said. "It's more of a fact that dogs are very, very, very observant of human behavior."

More information

To learn more about diabetes, visit the American Diabetes Association  .

WEDNESDAY, Sept. 19 (HealthDay News) -- Three-quarters of adult Americans polled recently said they knew little or nothing about peripheral arterial disease (PAD), a very common blockage of blood vessels in the legs that boosts heart risk.

"I don't think that was necessarily a surprise among physicians involved in PAD," said Dr. Timothy Murphy, a professor of diagnostic imaging at Brown University, who co-authored a report on the survey, published in the Sept. 18 issue of Circulation.

"Most of us know that many of the patients at risk don't seek medical attention," Murphy said. "But it was surprising that the knowledge base was as small as it was, considering that there are 8 million people in the United States with the disease."

Murphy is a member of the Peripheral Arterial Disease Coalition, which conducted the survey. The coalition is funded by grants from the Bristol-Myers Squibb/Sanofi Aventis Partnership (both members of the Partnership are drug companies) and medical device maker Cordis Endovascular, a division of Cordis Corp.

In PAD, arteries in the legs are narrowed or blocked with fatty deposits. These obstructions can cause leg pain but often produces no symptoms. PAD can damage legs enough to cause amputation, and it can also signal a raised risk of heart attacks or strokes caused by a narrowing of the arteries elsewhere in the body.

Three-quarters of the 2,051 people aged 50 and over queried via phone in the survey said they were aware of strokes, and two-thirds knew about risks of coronary artery disease and heart failure. But just 25 percent knew about PAD -- far behind awareness levels for much rarer conditions, such as amyotrophic lateral sclerosis or Lou Gehrig's disease (36 percent) and multiple sclerosis (42 percent).

Among the one in four adults who were aware of PAD, only 28 percent associated it with an increased risk of heart attack, and just 14 percent linked it with amputation and death.

That's no big surprise, Murphy said, since "the link between PAD and heart attacks and stroke is just becoming disseminated among primary-care physicians."

Relatively few family doctors routinely perform the basic diagnostic test for PAD, called the ankle-brachial index, he said. Blood pressure is measured in the arm and at the ankle, with the measurements repeated at both sites after five minutes of walking on a treadmill. Lower pressure at the ankle indicates PAD. The lower the ankle-brachial index, the greater the danger.

"The test is not often done in a primary-care physician's office," Murphy said. "It is not reimbursed under Medicare unless there are symptoms, and it is hard to ask physicians to do a test unless they are reimbursed. We are trying to get support for Medicare to reimburse for it as a diagnostic test."

Diagnosis of PAD indicates the need for attention to the well-known risk factors for arterial blockage elsewhere in the body, such as smoking, high blood pressure, cholesterol levels and lack of exercise, said Dr. Alan T. Hirsch, a professor of epidemiology and community health at the University of Minnesota, and another author of the report.

Lack of awareness means that even adults who have leg pains or other symptoms of PAD are not aware of its dangers, Hirsch said. "At a time when the public is bombarded with health messages, it would seem wise for those with one of the single most common cardiovascular diseases to be aware of the risk," he said.

The survey also shows that physicians are not doing enough about awareness of PAD risk, Hirsch said. While 26 percent of those in the survey who were aware of PAD said they got information from broadcast media such as television, only 19 percent reported first hearing about PAD from a health-care provider.

Physicians should be aware of PAD symptoms as a major warning sign of potential trouble, Hirsch said. "Denigrating leg pain as unimportant is as logical as avoiding chest pain," he said.

More information

Questions about PAD are answered by the PAD Coalition  .