Tag Archives: Purdue University

New type 1 diabetes therapy shows promise for long-term reversal in both humans, dogs

What if instead of daily insulin injections or wearing pumps, just getting a shot every few months could reverse Type 1 diabetes for you – or your dog?

It might take ushering in healthy pancreatic cells like a Trojan horse.

The Trojan horse, in this case, would be collagen, a protein that the body already makes for building muscles, bones, skin and blood vessels. A collagen formulation mixed with pancreatic cells, developed by Purdue University researchers in collaboration with the Indiana University School of Medicine, is the first minimally invasive therapy to successfully reverse Type 1 diabetes within 24 hours and maintain insulin independence for at least 90 days, a pre-clinical animal study shows.

For diabetic pets, the next step is a pilot clinical study in dogs with naturally occurring Type 1 diabetes, which will be conducted in collaboration with Purdue’s College of Veterinary Medicine.

“We plan to account for differences from mouse to human by helping dogs first. This way, the dogs can inform us on how well the treatment might work in humans,” said Clarissa Hernandez Stephens, first author on the work and a graduate researcher in Purdue’s Weldon School of Biomedical Engineering. Findings appear in early view for a forthcoming issue of the American Journal of Physiology – Endocrinology and Metabolism.

“With giving my dog shots twice a day, I have to constantly be thinking about where I am and when I need to be home. It greatly affects my work and my personal life,” said Jan Goetz, owner of a diabetic dog named Lexi. “Not having to give these shots would mean freedom.”

Type 1 diabetes affects about one in every 100 companion animals in the U.S., including dogs and cats, and approximately 1.25 million American children and adults.

David Taylor, an Indiana resident, has struggled with Type 1 diabetes for almost 50 years.

“A Type 1 diabetes diagnosis was my 18th birthday present, and since that first insulin injection, managing diabetes has been my ‘other’ full time job,” Taylor said. “Treatment methods have improved enormously over 50 years, but they still permit no time off for the patient. Receiving an injection every few months would restore the near-normal life to me that I haven’t had as an adult – and I could retire from that full-time diabetes management job.”

Because diabetes in dogs happens similarly in humans, treatment has so far been largely the same: Both need their glucose to be monitored throughout the day and insulin to be administered after meals.

This also means that dogs and humans could potentially benefit from the same cure: A new set of pancreatic cells to replace the clusters of cells, called islets, that aren’t releasing insulin to monitor blood glucose levels.

Still, 20 years of research and clinical trials hasn’t produced an effective islet transplantation therapy because multiple donors are needed, the current method of delivering islets through the portal vein of the liver is too invasive and the human immune system tends to destroy a large percentage of transplanted islets.

Purdue researchers simply changed how the islets were packaged – first, within a solution containing collagen, and second, as an injection through the skin instead of all the way at the liver, saving patients from a nasty procedure.

“Traditionally, we transplant islets in the liver of the animal and never do it under the skin, in large part because the skin doesn’t have the blood flow that the liver has for transporting insulin released by islets. And there are a lot of immune cells in the skin, so chances of rejection are high,” said Raghu Mirmira, professor of pediatrics and medicine and director of the Diabetes Research Center at the Indiana University School of Medicine.

The team removed the need for transplanting in the liver by thoroughly mixing mouse islets, provided by Mirmira’s lab, with the collagen solution. Upon injection just under the skin, the solution solidifies, the body recognizes the collagen and supplies it with blood flow to exchange insulin and glucose.

“It’s minimally invasive; you don’t have to go to the operating room and have this infusion into the portal vein. It’s as easy as it comes, just like getting a shot,” said Sherry Voytik Harbin, Purdue professor of biomedical engineering and basic medical sciences.

The researchers tested the effects of the solution between mouse twins and non-twins to check for discrepancies. Initial studies showed if the mouse donor were a twin to the recipient, the diabetic mouse could go at least 90 days without needing another shot. If not twins, the mouse would have normal blood sugar levels for at least 40 days. Nearly all transplanted islets survived either scenario, removing the need for multiple donors to compensate for those killed off by the immune system.

As they transition to testing the formulation in naturally diabetic dogs, the researchers will explore the feasibility of transplanting pig islets or stem cells programmed to produce insulin, in hopes that either method will further increase donor availability.

The islet transplantation therapy might also have implications for better treating severe pancreatitis.

Source:  Purdue University media statement

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Quantifying the Effects of Service Dogs for Veterans with PTSD

veteran with dog

 

Researchers from the Purdue University College of Veterinary Medicine’s Center for the Human Animal Bond will analyze the influence service dogs have on the lives of military veterans suffering from post-traumatic stress disorder (PTSD) in a unique clinical trial.

According to the United States Veterans Administration, 22 veterans commit suicide each day, and at least 40 percent have been diagnosed with PTSD. The rate could be even higher, as many cases of PTSD go undiagnosed.

Previous studies have suggested that individuals who bond with their pet dogs exhibit elevated levels of oxytocin – sometimes referred to as the “cuddle hormone” because it sparks emotional responses that contribute to relaxation and trust. Additionally, the National Center for PTSD claims dogs can encourage veterans to communicate more through commands and training, and prompt them to spend more time outdoors and meet new people.

These benefits support anecdotal reports that show an increase in the prevalence of service dogs for individuals with PTSD, but scientific evidence examining this growing trend and its effects on PTSD patients is still lacking.

“Many veterans are increasingly seeking complementary interventions for PTSD, including service dogs,” stated Maggie O’Haire, lead researcher and assistant professor of human-animal interaction at Purdue. “Yet, even with the well-meaning intentions of service dog organizations that are working to meet the demand, our systematic review of scientific literature confirms a lack of published, empirical research on the effects that service dogs have on veterans and their spouses.”

To help carry out the study, the research team has partnered with K9s for Warriors – one of the nation’s leading providers of service dogs to military vets suffering from a variety of conditions including PTSD, traumatic brain injuries, or sexual trauma as a result of service post-9/11.

The team hopes to determine what sort of PTSD symptom changes veterans may experience as a result of having a service dog, as well as any effects on social functioning and physiological biomarkers.

According to a university release, standardized survey instruments and objective measures of physiology will be used to track stress and functioning. The researchers will also use a novel ecological momentary assessment protocol to capture the role and function of the dogs in everyday life.

The results will be the first evidence-based data to be published that quantitatively identifies the roles and effects of service dogs for military veterans with PTSD.

The study is unique because it applies research methodology and evidence-based science to an area that has typically relied on emotion, according to O’Haire.

“Without scientifically sound studies that establish proof-of-concept for the therapeutic efficacy of PTSD service dogs, this animal-assisted intervention strategy will continue to be minimized as an unsupported and potentially unsound practice, despite anecdotal reports that the dogs may have a significant impact,” added O’Haire.

Source:  www.laboratoryequipment.com

A close up look at how our dogs drink…

The field of fluid dynamics explains how our dogs drink and why they splash and slop more than cats…

The drinking mechanism of a dog is videotaped from three different angles (A, B, and C). The curved tongue is rapidly withdrawn and a water column is formed underneath. A physical experiment is designed to understand and characterize the underlying fluid mechanics.  Photo by:  Sean Gart and Sunghwan (Sunny) Jung/Virginia Tech

The drinking mechanism of a dog is videotaped from three different angles (A, B, and C). The curved tongue is rapidly withdrawn and a water column is formed underneath. A physical experiment is designed to understand and characterize the underlying fluid mechanics. Photo by: Sean Gart and Sunghwan (Sunny) Jung/Virginia Tech

By studying the drinking habits of various dog breeds and sizes, a group of researchers at Virginia Tech and Purdue University has recently identified and modeled the fluid dynamics at play when dogs drink water.

“Three years ago, we studied how cats drink,” said Sunny Jung, an assistant professor at Virginia Tech. Jung’s research focuses include biofluid mechanics and the nonlinear interactions between soft bodies and surrounding fluids. His current project is sponsored by the National Science Foundation’s Physics of Living Systems program. “I was curious about how dogs drink, because cats and dogs are everywhere.”

As members of the order Carnivora, cats and dogs have incomplete cheeks, which allow them to open their mouths wide to deliver killing blows. But what makes pack hunting possible also makes suction drinking impossible. Unable to seal their cheeks completely, there is no way for a dog to suck up water. Conversely, humans have “complete” cheeks, and we drink by creating negative pressure, allowing us to suck water into our mouths and down our throats.

Cats, too, lack suction, and they compensate by drinking via a two-part “water entry-and-exit” process. This consists of a plunging and a pulling phase, in which a cat gently places its tongue on the water’s surface and then rapidly withdraws it, creating a column of water underneath the cat’s retracting tongue.

“When we started this project, we thought that dogs drink similarly to cats,” Jung said. “But it turns out that it’s different, because dogs smash their tongues on the water surface — they make lots of splashing — but a cat never does that.”

When dogs withdraw their tongue from water, they create a significant amount of acceleration — roughly five times that of gravity — that creates the water columns, which feed up into their mouths. To model this, Jung placed cameras under the surface of a water trough to map the total surface area of the dogs’ tongues that splashed down when drinking.

The researchers found that heavier dogs drink water with the larger wetted area of the tongue. This indicates that an allometric relationship exists between water contact area of the dog’s tongue and body weight – thus the volume of water a dog’s tongue can move increases exponentially relative to their body size.

In order to better understand how the physiology works, Jung and his colleagues could only go so far by watching dogs drink. They had to have the ability to alter the parameters and see how they affected this ability, and since they could not actually alter a dog in any way, they turned to models of the dog’s tongue and mouth. “We needed to make some kind of physical system,” Jung said.

For their model, Jung and his colleagues used glass tubes to simulate a dog’s tongue. This allowed them to mimic the acceleration and column formation during the exit process. They then measured the volume of water withdrawn. They found that the column of water pinches off and detaches from the water bath primarily due to gravity. Dogs are smart enough to close their mouth just before the water column collapses back to the bath.

Source:  Newswise media release

How dogs detect explosives

Photo courtesy of Indiana University-Purdue University Indianapolis

Photo courtesy of Indiana University-Purdue University Indianapolis

A research team at Indiana University-Purdue University Indianapolis (IUPUI) has helped determine the science behind how dogs locate explosives such as Composition C-4 (a plastic explosive used by the U.S. military). The study found the dogs react best to the actual explosive, calling into question the use of products designed to mimic the odor of C-4 for training purposes.

These findings are the culmination of a four-year contract funded by the U.S. Department of Defense (DOD).

“Appropriately, dogs that are trained to find real explosives are going to find real explosives and not much else,” said John Goodpaster, Ph.D., associate professor of chemistry and chemical biology and director for the Forensic and Investigative Sciences Program in the School of Science at IUPUI.

The effectiveness of trained detector dogs is well established, but the study sought to determine which chemical compounds cause a dog to recognize a particular explosive and alert to it. Previous studies have suggested that certain non-explosive chemicals emitted by Composition C-4 cause dogs to alert, and that these specific chemicals could be used as mimic substances to train the dogs in place of real explosives.

The research team discovered that the non-explosive chemicals given off by C-4 mimics also are present in a variety of everyday plastic objects. Objects tested included PVC pipes, electrical tape, movie tickets, a plastic grocery bag and plastic food wrapping. Several of the tested items emitted appreciable levels of a mimic compound recommended by some vendors for training dogs.

The second phase exposed 33 trained canines from the DOD, Department of Justice, Amtrak and other agencies to these vapors to see if the dogs would respond. The field trials demonstrated that the dogs failed to respond in any significant way to specific odor compounds found in C-4. The results indicate that if the dogs are trained on the full scent, they will only detect real explosives.

The study findings have been published in the March 2014 edition of the journal Forensic Science International.

Source:  IUPUI media release

Would a raised dog feeder help my dog?

A massage client asked me this question earlier this week.   The dog in question is a Boxer (beautiful boy) who happens to be suffering from degeneration in his spine.

Although he is doing well with regular swimming, acupuncture and massage therapy, his owner knows that he is comparatively young (8) and she wants him to have a good quality of life for a long time.  So that’s when we started talking about changes she could make to his physical environment to make things less stressful for him (ramps, steps, etc.)

Would a raised feeder help my dog?

Raised feeders can be a real advantage for a dog with orthopaedic problems or arthritis.  Eating from a raised feeder helps to relieve strain on the neck and back, allowing the dog to eat without dramatically altering their posture and helping them to retain balance.

But – some studies have shown that dogs who are susceptible to bloat have an increased risk from eating from a raised feeder.  The most notable reference for this link is an article by Dr Larry Glickman in Journal of the American Veterinary Medical Association, Vol. 17, No. 10.

Gastric dilation-volvulus (GDV) is known by the common term ‘bloat’  and other terms such as ‘stomach torsion’ or ‘twisted stomach.’  Regardless of what name you use, the condition is life-threatening.  Dogs can die of bloat within several hours.   Even with treatment, as many as 25-33% of dogs who develop bloat will die.

In bloat, the stomach fills up with air and puts pressure on the other organs and the diaphragm. The pressure on the diaphragm makes it difficult for the dog to breathe. The air-filled stomach also compresses large veins in the abdomen, preventing blood from returning to the heart.

Filled with air, the stomach can easily rotate on itself, pinching off its blood supply. This rotation is known as volvulus.  The stomach begins to die and the entire blood supply is disrupted.  A dog with this condition can deteriorate very rapidly – meaning a trip to the vet as an emergency.

Purdue University ranks Boxers as the 16th breed most susceptible to bloat (Great Danes are the highest).  So, in this case, the owner decided not to opt for a raised feeder.  Not only is her Boxer on the higher risk list, but he also is a gobbler – making quick work of his food!

This is just one example where it pays to do a little research.  An idea that seems like a good one may not be so.