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Endocrinologists have been presenting new concepts at a meeting of the American Diabetes Association in San Diego, and last week, U.S. regulators released new draft guidelines for a new generation of devices.

Researchers at the Mayo Clinic are developing an artificial pancreas that accounts for slight, low-intensity physical activities that can impact blood sugar levels. The researchers are developing a closed-loop system that includes a glucose monitor, automatic insulin pump, activity monitors that attach to the body and a central computer that uses an insulin-delivery algorithm to determine how much of the hormone to dispense.

A team led by Yogish Kudva at Mayo hooked up diabetics with accelerometers to measure slight movements, and tracked their blood sugars while they moved around after eating a meal. They found that even limited, basic movements had a major impact on blood sugar levels, bringing them close to those of people with normally functioning pancreases. But insulin pumps and glucose monitors don’t account for those slight differences. New algorithms that adjust for those changes could help diabetics better manage their insulin intake, the Mayo researchers said. The team plans to start a clinical trial with the system this year or early next year, according to Bloomberg.

In another study, researchers at Yale University tested an artificial pancreas that automatically senses and regulates glucose throughout the night, and found it worked better than a traditional insulin pump. Twelve patients were hooked up to a glucose monitor manufactured by Medtronic Inc., which sent signals to a laptop, where algorithms calculated how much insulin to administer. The system is simple enough that it could eventually be integrated into a wearable device, according to the researchers.

The Food and Drug Administration last week announced draft guidelines for how to develop some of these systems, including a “low glucose suspend system,” which cuts off insulin delivery when blood sugar levels drop. The device is already approved in Europe.

The FDA plans to release even more detailed plans for closed-loop artificial pancreases by the end of the year, according to Bloomberg.

[Science Daily, Bloomberg]

600 calories per day

Seven of the 11 patients remained free of diabetes three months after the study, researchers said.

Type 2 diabetes, also known as adult-onset diabetes, has been thought to be a progressive, irreversible condition. Once diagnosed, some patients can control their diabetes with tablets, but many eventually require insulin injections.

Type 2 diabetes occurs when the pancreas is unable to produce sufficient insulin to regulate fat metabolism and sugars in the blood, or when the body is unable to react to the insulin. It’s different than Type 1, or juvenile diabetes, an autoimmune disorder in which the immune system destroys the beta cells that produce insulin.

The study was announced Friday at an American Diabetes Association conference, according to Newcastle University. It is being published in the journal Diabetologia.

The study enrolled 11 patients who had developed Type 2 diabetes later in life, and restricted them to a super-low-calorie diet consisting of diet drinks and non-starchy vegetables. Over eight weeks, researchers monitored the fat content in the liver and the insulin production from the pancreas, comparing the results to a control group of non-diabetics.

After just one week, the diabetics’ pre-breakfast blood sugar levels were normal, according to the researchers. MRI scans of the patients’ pancreases revealed that fat levels had dropped, which allowed the organ to produce more insulin, the researchers said.

“To have people free of diabetes after years with the condition is remarkable - and all because of an eight week diet,” said Roy Taylor, a professor at Newcastle University who led the study and is director of the Newcastle Magnetic Resonance Centre. “We believe this shows that Type 2 diabetes is all about energy balance in the body.”

While the results are promising, researchers caution that diabetic patients should not undertake such a drastic dietary change without medical supervision. One patient, 67-year-old Gordon Parmley, ate salad and vegetables and three diet shakes per day.

“At first the hunger was quite severe and I had to distract myself with something else – walking the dog, playing golf – or doing anything to occupy myself and take my mind off food,” he said in a statement. “But I lost an astounding amount of weight in a short space of time ... after six years, I no longer needed my diabetes tablets.”

Scientists at Diabetes UK said the trial was very small, but they looked forward to future results, especially those that would show whether the diabetes reversal held true in the long term.

[Newcastle University]

Pig cells wrapped in seaweed will be implanted into diabetes patients

Type 1 diabetes occurs when insulin-producing cells in the pancreas are destroyed. As such, people suffering from the condition must inject insulin into their bloodstreams to regulate their glucose levels, but doing so can cause swings in blood sugar that can lead to other complications. The Russian treatment replaces the missing cells with pig cells that produce insulin inside the body, reducing the need for injections. The seaweed coating keeps the bodies immune system from attacking the foreign animal cells.

Though approved in Russia, the treatment was developed by Living Cell Technologies in New Zealand. In Russian trials, the treatment fared fairly well, exhibiting improvement in six of eight diabetes patients who were then able to reduce their daily insulin injections. Two of them were able to cease injections entirely.

[New Scientist]

Men with type-1 diabetes might be able to grow new insulin cells from their own testicular tissue, according to a new study. Testicular treatment could even be safer and more effective than stem-cell therapies.

Researchers at Georgetown University Medical Center were able to coax human spermatogonial stem cells, which are precursors to sperm cells, into becoming adult stem cells. Sperm cells already have the genes necessary to become embryonic stem cells, the researchers point out in a Georgetown news release. This way, the researchers didn’t have to use gene therapy to create induced pluripotent stem cells (IPS cells) — “These are true, pluripotent stem cells,” said G. Ian Gallicano, an associate professor in the Department of Cell Biology and Director of the Transgenic Core Facility at GUMC.

The team took one gram of tissue from human testes from deceased organ donors and produced about one million stem cells in the lab. The cells showed many of the biological markers that characterize normal beta islet cells, which are insulin-secreting cells normally found in the pancreas. Then the team transplanted the cells into diabetic mice, and were able to decrease the animals’ glucose levels.

The proof-of-concept study could yield a new, safer treatment for type 1 diabetes, also called juvenile diabetes. Current treatments include transplanting islet cells from deceased donors, but this can result in rejection, and there are only so many donors. Researchers have cured diabetes in mice using IPS cells, but these can produce tumors as well as problems stemming from the external genes used to create IPS cells, according to Gallicano. The new method bypasses IPS cells, because sperm cells are already a form of stem cells. The study was reported Sunday at the American Society of Cell Biology 50th annual meeting in Philadelphia.

The round device is just a bit smaller than a Double-Stuf Oreo -- about 1.5 inches wide and half an inch thick -- and would be implanted in a person's torso. It's hermetically sealed, with an integrated antenna that wirelessly transmits data, a long-lived battery, and a pair of sensors. One sensor detects only oxygen, the other a reaction that involves both oxygen and glucose. No matter how dense the scar tissue surrounding the implant, the two-sensor combination compensates, allowing the device to correctly calculate glucose levels in the blood.

Most complications from diabetes, from blindness to heart attacks, can be mitigated with monitoring -- obsessive monitoring that involves blood-drawing finger pricks every 15 minutes, day and night. Most diabetics don't even test every hour.

The most advanced technology currently available for continuous monitoring uses a needle-sized sensor that pokes deep into the skin, connected via a wire or wireless transmitter to a pager-sized monitor. It provides blood-sugar levels in close-to-real time, but it's also a bit bulky and inconvenient: The needle-like sensors must be recalibrated daily and replaced every three to seven days, before the body encapsulates them with scar tissue and renders it useless.

Such rapid obsolescence doesn't apply to the implantable device, which was developed by researchers at the University of California at San Diego and biotech company GlySens. "The sensor we developed was designed from the beginning to be a long-term device, and designed to operate for very long periods," says David Gough, the UCSD bioengineer who led the research. In a paper published online today in Science Translational Medicine, Gough and his colleagues show that their sensor can function successfully for over 500 days -- at least in pigs. They hope to begin the first human trial later this year, and are hoping for FDA approval within three years.

Right now, the device transmits its data directly to an external display. But ultimately, the researchers hope that ultimately data from their sensor could be transmitted directly to a patient's smartphone, eliminating the need for any additional hardware. In combination with other technologies in development -- an algorithm-crunching computer that uses glucose data to calculate how much insulin a person needs to control his blood sugar, and an automatic insulin pump to dispense the dose -- the new sensor could help create a low-maintenance system that does the work of a pancreas.

"Continuous glucose monitors are very helpful, but the key thing is that you have to wear them, and that's a big challenge for many people," says Aaron Kowalski, research director for the Juvenile Diabetes Research Foundation's artificial pancreas project. He notes that, because current devices are still slightly conspicuous and require vigilance, teenagers and young adults are less likely to wear them. "So the idea of having a one-year sensor that is implanted is very, very appealing. A device that alleviates some of these real-life issues means you don't have to insert so much, you don't have to see it, and you can walk around and not have all this stuff stuck to you."

Insulin needs to be kept cold because it is made of weak chemical bonds that degrade at temperatures above 40 degrees Fahrenheit, making it inactive. But using a series of chemical reactions, the research team, comprised of students from Monash University in Australia, replaced the unstable bonds with stronger, carbon-based ones.

The stronger bonds stabilize the insulin's two protein chains without interfering with its natural activity, according to a story about the findings at SciGuru.

The so-called "dicarba" insulins were stable at room temperature for several years, SciGuru says.

Even more promising is that the findings provide insight into how insulin works.

People with Type 1 and Type 2 diabetes do not produce enough insulin, whether it's the result of an auto-immune disorder that stops producing it entirely (Type 1) or a condition brought on by other factors like obesity, in which the body can no longer use it properly (Type 2). Insulin is the mechanism that delivers glucose from the blood to the cells, so diabetics must take a synthetic form of the hormone.

When insulin unlocks cells to allow sugar to be taken up from the blood, the hormone's shape changes -- but no one is sure what the shape looks like. If researchers knew that shape, they could design smaller, less-complex versions of insulin that don't use proteins.

Then it could be administered in pill form rather than directly into the bloodstream. Understanding the molecule's chemical bonds is a step toward unlocking that shape, the researchers say.

[SciGuru]

A new diagnostic test developed by researchers at ETH Zurich can tell if a patient has Type I diabetes, but gone are the days of blood samples and lab work. The new nanotech sensor can tell instantly if a patient has diabetes or an associated complication called diabetic ketoacidosis by simply analyzing a sample of exhaled breath.

The sensor -- a breathalyzer of sorts for diabetes -- scans the breath for high levels of acetone, a biomarker associated with Type I diabetes. If an exceptionally high level of acetone is detected, it's a strong indicator that the person is suffering from ketoacidosis, a potentially serious buildup of acetone in the blood that occurs when insulin levels fall too low.

The sensor takes advantage of a the properties of tiny ceramic nanoparticles that are laid in a thin film between two gold electrodes inside the device. Those particles act like a kind of electrical resistor, but when acetone comes in contact with the sensor that resistance is diminished. Small amounts of acetone don't drastically affect the sensor, but in doses indicative of diabetes the resistance is noticeably altered, allowing electricity to flow between the electrodes more freely and raising red flags. The higher the acetone level, the redder the flag.

With sensitivity at 20 parts acetone per billion, the sensor can detect acetone at levels 90 times lower than that found in the breath of diabetics, so the chance of it missing a diagnosis is very low. It could provide emergency room techs a quick diagnostic tool with which to determine if a diabetic patient has developed ketoacidosis. But it has more practical uses as well; as costs come down, it could be used by diabetics in the home to determine if they need to take more insulin, skirting the problem of ketoacidosis altogether.

[Science Daily]