Tag Archives: Duke University

A ‘Robo-Nose’ Could Give K-9 Officers a Break

Robonose golden retriever

Golden retriever Rudy, wearing military dog tags and a U.S. flag, is being trained by the U.S. Army to use his amazing nose to find human remains. (Army photo)

Every day, thousands of trained K9 dogs sniff out narcotics, explosives and missing people across the United States. These dogs are invaluable for security, but they’re also very expensive and they can get tired.

Duke researchers have taken the first steps toward building an artificial “robot nose” device made from living mouse cells that officers could use instead of dogs.

The researchers have developed a prototype based on odor receptors grown from the genes of mice that respond to target odors, including the smells of cocaine and explosives. Their work appeared earlier this month in Nature Communications.

It turns out, there are a couple of very big differences between testing things in a lab dish and testing them in an actual nose.

“This idea of an artificial nose has been present for a long time,” said senior study author Hiroaki Matsunami, a professor of molecular genetics and microbiology in the Duke School of Medicine. “The receptors were identified in the 1990s, but there are significant technical hurdles to produce all these receptors and monitor the activity so that we can use that in an artificial device.”

“E-noses” that exist now use various chemical compounds to detect smells instead of receptor stem cells, Matsunami said. He said those devices are “not as good as a trained dog.”

“The idea is that by using the actual, living receptors, maybe we can develop a device similar to animals,” Matsunami said. “Nobody has achieved that yet, but this study is moving toward that goal.”

Human, dog and mouse genomes contain around 20,000 genes, which contain instructions to create proteins that smell, taste, feel, move and do everything that our bodies do. About 5 percent of mouse genes have been identified as instructions to make odor receptors, Matsunami said. In contrast, humans only use about 2 percent of their genes to make odor receptors.

“These animals invest a lot of resources for this purpose,” Matsunami said. “Mice and rats are very good smellers; we just don’t use mice for detecting explosives in real life. There are some practical problems to do that.”

The first step of the study was to identify the best odor receptors to respond to target odors like cocaine or marijuana.

The researchers created a liquid medium primed with molecules that could light up from reactions. Next they copied about 80 percent of the odor receptors from mice, and mixed those receptors with seven target odor chemicals in the medium.

They measured the resulting luminescence and chose the best-performing odor receptors for the second part of the study, which monitored receptor activation in real time.

Previous research had done this by exposing selected receptors to odor chemicals in a liquid. But there are several differences between the petri dish and the nose. For one, we rarely submerge our noses into liquid baths of odor chemicals. Instead, our noses detect smells from wafting perfumes or stenches borne on the air. And our noses are full of mucus.

So, for the second half of the study, which was supported by the National Institute of Health grants DC014423 and DC016224 and the Defense Advanced Research Project Agency RealNose Project, they attempted to mimic how we use our noses by exposing odorants to vapors and a few enzymes.

The researchers tested the receptors they had identified against two odor vapors for this study.

“We only tested two of them in the paper, but it’s showing the proof of principle of how it can be used,” Matsunami said.

The researchers hope they can fine-tune the device to test all receptors against many different smells.

“We have a panel of receptors so we can monitor how different receptors respond differently to various smells, including ones that are similar to each other in chemical structure or ones that might be related to real-world use, like something associated to explosives or drugs,” Matsunami said.

The researchers also tested various enzymes that one might find in mucus to see how they aided or impeded reactions. This process is more true-to-life than vapor molecules directly interacting with odor receptors.

“You’d think when we smell a chemical, the chemical would bind to the chemical receptor in the nose, but actually it’s not so simple,” Matsunami said. “When the chemical dissolves in the nasal mucus before binding to the receptor, it might be converted to another chemical by enzymes in the nasal mucus.”

Mucus is an unknown frontier in understanding how we smell. Reconstructing the key components of nasal mucus may be the next step toward building an artificial nose, according to the paper.

“It’s not like our paper will be immediately applied to a portable device used in the airport soon, but this is an important step forward to show that it is possible,” Matsunami said. “We can more clearly see what kind of hurdles to pass in order for the community to create such a device.”

Three of the authors have filed a patent application for the work.

Source:  Duke University

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The dogs of the In Situ Foundation

The In Situ Foundation based in Chico, California, has spent the last 12 years developing scientific protocols that are needed to train cancer detection dogs and their handlers.  In collaboration with top research universities including Duke and UC Davis, they rescue dogs and train them to sniff out specific cancers.  All training is reward based.

What I particularly like about this registered charitable foundation is their mission to use rescue dogs “Our mission is to use shelter/rescue dogs whenever possible. We adopt dogs and give them loving homes, so what could have been a dog on death row, is now being trained to save human lives. All dogs are “super sniffers”, so we do not believe in breeding them, or creating a “super sniffer” breed.”

The dogs of In Situ live in residential homes with their adoptive families.  Their day jobs are to go to work at the Foundation.

Here are the current dogs in the In Situ team:

Stewie

Stewie is a 5 year-old, female, Australian Shepherd. She has been one of In Situ’s best dogs, and has been trained to detect early stage lung, ovarian, and breast cancer. She was one of our star dogs in a 2012 ovarian cancer study, and she is also on Duke University’s canine team for breast cancer. Stewie has also competed in agility, obedience, and is a certified therapy dog with Pet Partners and LA Children’s Hospital, where she visits sick children. Stewie was nominated for the 2015 American Hero Dog Award, given by the American Humane Association. Stewie is a beautiful, loving, smart and talented dog, who loves her work more than anything, except the frisbee.

Leo

Leo is a 2 year-old, male German Shepherd, that In Situ Foundation adopted from Westside German Shepherd Rescue. Leo was on death row, and he was scheduled to be euthanized. He is a wonderful, loving, friendly and well-trained dog, and he’s very valuable to In Situ’s team. Leo is on the team of dogs working in conjunction with Duke University on a two-phase, breast cancer trial.
Charlie

Charlie is the newest addition to the team.  She is a six week-old German Shepherd from champion lines (from Nadulhaus German Shepherds) and will be one of the first dogs in the world trained on upper thoracic (head, neck and throat) cancer, using saliva samples. After 12 to 18 months of training with In Situ Foundation, she will be owned and loved by Dr. Peter Belafsky (University of California, Davis) and will work with him to sniff samples in clinical trails, which will help advance protocols to detect cancer at its earliest stages through olfaction.

Linus
Linus is a 3 year-old male German Shepherd who was also on death row, and adopted by In Situ Foundation. He was returned to the shelter three times by his previous owner. When he came to our ranch and got his first “job”, it literally transformed Linus’s life. Linus went from a small “jail cell” to a life of love and play. He’s happy, balanced, and well adjusted, and he’s the most loving boy around! Linus loves his work, and he’s a gem on our cancer detection team. Linus also works on the Duke team of breast cancer detection dogs.
alfie
Alfie is another new addition to the In Situ team. He will be owned and loved by Dr. Hilary Brodie, Chair of Otolaryngolgy at University of California, Davis. Alfie is a Labradoodle (Lab/Poodle hybrid) who will also be trained to detect upper thoracic cancers, and he will be working toward advancing bio-detection by canines at UC Davis.
Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

Adjusting stress levels for mellow vs hyper dogs

People aren’t the only ones who perform better on tests or athletic events when they are just a little bit nervous — dogs do too. But in dogs as in people, the right amount of stress depends on disposition.

A new study by researchers at Duke University finds that a little extra stress and stimulation makes hyper dogs crack under pressure but gives mellow dogs an edge.  (These findings will be relevant to any owner who is competing in agility or obedience with their dog.)

The findings appear online in the journal Animal Cognition.

According to an idea in psychology called the Yerkes-Dodson law, a little stress can be a good thing, but only up to a point.

A task that isn’t demanding or challenging enough can make it hard to stay engaged and perform at one’s peak. But when the pressure becomes too much to handle, performance is likely to suffer again.

The idea is the relationship between stress and performance follows a Goldilocks model:  Both people and animals function best when the level of stress is not too much, nor too little, but just right.

When you’re taking a test, for example, it helps to be a little bit anxious so you don’t just blow it off,” said study co-author Emily Bray, who was an undergraduate at Duke at the time of the study. “But if you’re too nervous, even if you study and you really know the material, you aren’t going to perform at your best.”

Researchers first observed this pattern more than a hundred years ago in lab rats, but it has since been demonstrated in chickens, cats and humans. In a new study, a Duke team consisting of Bray and evolutionary anthropologists Evan MacLean and Brian Hare of Duke’s Canine Cognition Center wanted to find out if the conditions that enable certain animals to do their best also depend on the animal’s underlying temperament.

In a series of experiments, the researchers challenged dogs to retrieve a meat jerky treat from a person standing behind a clear plastic barrier that was six feet wide and three feet tall. To get it right, the dogs had to resist the impulse to try to take the shortest path to reach the treat — which would only cause them to whack into the barrier and bump their heads against the plastic — and instead walk around the barrier to one of the open sides.

In one set of trials, an experimenter stood behind the barrier holding a treat and called the dog’s name in a calm, flat voice. In another set of trials, the experimenter enthusiastically waved the treat in the air and used an urgent, excited voice. (See YouTube video at https://youtu.be/j6bfo5IlCEY – the video has been protected and so I’m unable to link it directly to this blog post).

The researchers tested 30 pet dogs, ranging in age from an eight-month-old Jack Russell terrier named Enzo to an 11-year-old Vizsla named Sienna. They also tested 76 assistance dogs at Canine Companions for Independence in Santa Rosa, California, a non-profit organization that breeds and trains assistance dogs for people with disabilities.

The researchers studied video recordings of each dog and estimated their baseline temperament in terms of tail wags per minute. “The service dogs were generally more cool in the face of stress or distraction, whereas the pet dogs tended to be more excitable and high-strung,” Bray said.

Both groups of dogs were able to solve the puzzle. But the optimal amount of stress and stimulation depended on each dog’s disposition.

For the dogs that were naturally calm and laid-back — measured by how quickly they tended to wag their tails — increasing the level of excitement and urgency boosted their ability to stay on task and get the treat.

But for excitable dogs the pattern was reversed. Increasing the level of stimulation only made them take longer.

In one high-arousal trial, a two-year-old spaniel named Charlie Brown lost it and shut down, barking and zipping around crazily until she almost ran out of time.

“In the first five trials she did fine and solved the puzzle quickly with no problems,” Bray said. “Then when the high-arousal trials started she choked. She just couldn’t figure it out.”

“Adding more excitement pushed the pet dogs over the edge and impaired their ability to perform at their peak,” Bray said.

The results will help researchers develop better tests to determine which dogs are likely to graduate from service dog training programs, for example.

Source:  Duke University media release

The Genius of Dogs – book review

The genius of dogsI have just finished reading The Genius of Dogs by Brian Hare and Vanessa Woods.  It’s a keeper!

I’ve always felt that many people don’t give our dogs the credit they deserve; they are not ‘dumb animals.’  This book outlines research into dog cognition and what it means for your relationship with your dog.

Hare, who is the founder of the Duke Canine Cognition Center, started his research at the young age of 7 with his dog Oreo.  He used a basic cognitive test involving two cups and a treat to test whether Oreo would respond to hand signals.  Later in life, as part of his research, he travels to places like the Congo to work with bonobos, Australia to observe dingoes on Fraser Island, and New Guinea to test a group of New Guinea Singing Dogs.

Here are a few of my favourite excerpts from this book:

  • People who own pets tend to be more extroverted, less lonely, and have higher self-esteem than people who do not own pets.
  • Breed-specific laws based on appearance as opposed to bad behavior are doomed to fail in protecting the public because it is difficult to judge a dog by her cover.
  • In return for a lifetime of loyalty, they (dogs) depend on us for food, the warmth of a loving family, and a good home.  It is up to us to uphold our end of the bargain.

This book is thoroughly referenced with 67 pages of end notes, something I believe is as an indicator of quality.

Enjoy this book, from its first page to last.  I found the book’s dedication particularly poignant…

For all dogs

Lymphomas in humans and dogs have similarities

A team of scientists from the University of North Carolina School of Medicine, North Carolina State University’s College of Veterinary Medicine and Duke University have conducted one of the first studies to directly compare canine and human B-cell lymphoma by examining molecular similarities and differences between the two species.

B-cell lymphomas are very common in both humans and dogs.

“Pet dogs get cancer the same way humans do: at similar rates, and for unknown reasons.  Like humans, dogs’ tumors are spontaneously occurring, rather than genetically created as they are in mice, so canine tumors may more accurately mimic the situation in human cancer patients. Dogs are good models to study, because it will also be possible to study shared risk factors, in the environment, for example, that might predispose both humans and dogs to get lymphoma. Our knowledge helps dogs and humans with lymphoma.” says Kristy Richards, MD, PhD, and co-author of the research which has been published in the journal Cancer Research.

“Veterinarians treating dogs for lymphoma can offer clinical trials to their owners. Clinical trials in dogs are similar to those done in humans, with safety protections in place to minimize harm.”

Molecular analyses of canine and human tumors were completed at NCSU and at UNC Lineberger. The team used gene expression profiling and found that canine B-cell lymphoma expression profiles were similar in many ways to human B-cell lymphoma, thus paving the way for future studies, including therapeutic clinical trials in dogs and humans.

Source:  UNC School of Medicine media statement