How Animals can Save us -- White Paper
By Linda Shultz, DVM, Ph.D., Ivanhoe Health Correspondent
(Ivanhoe Newswire) -- “DOGNOSES.” More than man’s best friend or a Frisbee-catching champion, dogs are trained to detect bombs, sniff out drugs, find earthquake and avalanche victims and, now, detect cancer. In Tallahassee, Fla., a Schnauzer named George was trained to detect melanomas, a type of skin cancer that many times is not discovered in time to successfully treat the patient. Armand Cognetta, M.D., a dermatologist specializing in cancer in Tallahassee teamed with veteran police dog trainer Duane Pickel and senior study author James Walker, Ph.D., head of the Sensory Research Institute at Florida State University in Tallahassee, to train George, and another dog, Breeze, to sniff out melanoma. 1,2
Over 47,000 new cases of melanoma are diagnosed every year in the United States. Current medical practice relies primarily on unaided visual inspection, although many melanomas are colorless rendering them invisible. This is part of the reason why some melanomas are not discovered in time for successful treatment.
A 1989 study in The Lancet highlighted a patient whose dog persisted in exploring a spot on the patient’s leg that was found to be melanoma.3 It was this work that spurred Walker’s team to begin their study. The researchers trained George and Breeze using methods normally used in canine olfactory detection of drugs and explosives. They demonstrated reliable localization of melanoma tissue samples hidden on the skin of healthy volunteers. George confirmed melanoma in five patients that was clinically suspected and later confirmed to be melanoma. Breeze duplicated these findings.
According to Paul Waggoner, Ph.D. director of the canine program at the Institute for Biological Detection Systems at Auburn University in Alabama, dogs are equipped with the right smelling tools and are easily handled by people -- two critical factors for their success in the detection field. He says, “Dogs can smell from 1,000- to 100,000-times better than people and they are not only odor-guided, but have a vast capability to detect one odor in an odor-rich environment.”
Understanding how dogs detect cancer may help develop new technology detect cancers earlier. Although the compounds a dog might smell in a cancer sample are unknown, research in this area may lead to new ‘smelling machines’ designed to detect cancer in the early stages.
Walker and colleagues are also discussing ways to detect early-stage lung cancer using bronchoalveolar lavage samples from patient’s lungs.
Dr. Barbara Sommerville, from Cambridge University in Cambridge, England is also using dogs to sniff out cancer. She and colleagues have applied for funding to test dog’s ability to detect prostate cancer in urine samples, a test that may provide a better early warning system than those in place. The current test is a serum test that turns up a lot of false positives and some false negatives. Because the next step is to perform multiple biopsies, this presents a problem. Dr. Sommerville doesn’t know what the dogs will smell, but she believes urine from a prostate cancer patient will be different. 4
Is the doctor’s office the final frontier for the hound? It is unlikely because dogs like to move around, which is impractical in a medical setting. The most likely scenario is that this research will lead to better instrumentation to detect cancers early.
PETS AND PEOPLE
More than 70 years ago researchers found that stroking a dog lowers the dog’s blood pressure. However, it wasn’t until 1984 that scientists learned the blood pressure also decreased in the person petting the dog. 1 Others reported a positive correlation between pets and their owners’ cholesterol and triglyceride levels. There were also symptomatic indications of anxiety and stress relief in people who owned pets. From these meager beginnings exploded the field now known as Human-Animal Interaction. Marty Becker, D.V.M., author of The Healing Power of Pets, which details this field, simply refers to it as The Bond.2 Once skeptical physicians and scientists are now discovering the remarkable power of animals to detect disease and provide healing in a host of medical and emotional conditions. Many doctors are even “prescribing” pets as part of combinatorial therapy for their patients.
One of the most outward signs of the field’s validity is the creation of the nation’s first Center for Human-Animal Interaction in the School of Medicine at Virginia Commonwealth University. Sandra Barker, Ph.D., professor of psychiatry, directs the center. She says, “It’s has been my dream come true. We have faculty from all parts of the school participating, including gerontology, the business school, addiction psychiatry, and epidemiology. There are so many people interested in this area.” She also holds an adjunct appointment at the Center for animal-human relationships at Virginia Tech’s veterinary school. Many veterinary schools now have departments devoted to this area of research. The American Association of Medical Colleges reported last year that, of the 125 US medical schools in the United States, 76 offer courses in complementary and alternative medicine as part of their required curriculum. Even more government funds are becoming available to study alternative medicine, the category in which animal-human interaction falls.
The number of organizations whose mission is the promotion and celebration of the human-animal bond are rapidly increasing. The Delta Society, the first known group established in 1977, promotes awareness of the positive effects animals have in people’s lives, in addition to expanding the roles of animals in human health, education and therapy. 3
Merial, the world’s leading animal pharmaceutical company, recently created PAWSitive InterAction, 4 a first of its kind non-profit community alliance of Atlanta’s premier animal organizations. “The foundling members of PAWSitive InterAction are bound together by a common commitment to promote and celebrate the positive impact of the human-animal bond,” says Nalini Saligram, Ph.D., Merial Corporate Communications Director. The alliance includes the Atlanta Humane Society, Happy Tails Pet Therapy, Zoo Atlanta, and Pets are Loving Support (P.A.L.S.).
PETS HELP AND HEAL
PAWSitive InterAction held their second annual summit on pets and the aging, hosted by Emory University by Emory Center for Health in Aging. The summit brought together researchers working in the field to present scientific research and case studies that validate the beneficial effects of human-animal relationships. Science is finally substantiating what millions of pet owners have known intuitively for years; pets help and heal. Here are some examples:
1. PETS DECREASE BLOOD PRESSURE: Karen Allen, Ph.D., State University of New York, Buffalo, found that stockbrokers on medication for hypertension who were assigned to get a pet experienced half the increase in blood pressure during stressful situations as those without a pet. In fact, many of the stockbrokers in the “no pet” group went out and got a pet following the six month study. 5
2. PETS DECREASE STRESS LEVELS BETTER THAN A SPOUSE: The same group, in another study, showed that having a pet present during stressful situations, such as completing mental math problems or submerging a hand in ice water for two minutes, reduced the pet owner’s stress level more than a spouse or close friend. Participants made the most math errors when their spouses were present. Dogs and cats were equally capable of providing stress relief. 6
3. PETTING A DOG MAKES PEOPLE FEEL GOOD: Petting a dog makes people feel good, but, until now, mechanistic research as to why this happens has been limited. Johannes Odendaal, DVSc, Ph.D., of Technikon Pretoria in South Africa, considered a pioneer in this field, says both dogs and people experience beneficial hormone changes in endorphins, beta phenylethylamine, prolactin, dopamine and oxytocin within 15 minutes of a quiet interaction. There is also a decrease in the stress hormone cortisol in the person. 7
Rebecca Johnson, Ph.D., RN, of the University of Missouri-Columbia Center for the study of Animal Wellness, is following up on Odendaal’s work. Her group has preliminary data supporting Odendaal’s work and is looking at additional brain chemicals, such as serotonin. Johnson, in collaboration with Richard Meadows, University of Missouri’s College of Veterinary Medicine, is also trying to determine if the biochemical changes result from a happy interaction or if something within the living animal itself triggers the response. To find out, they are asking whether the beneficial human biochemical changes that occur with dogs still occur if the animal is made of metal, a robotic dog. The results won’t be out for about a year, reports Johnson. The results could suggest new ways to treat a variety of human ailments.
4. HEART ATTACK VICTIMS WITH PETS LIVE LONGER: Researchers from the Department of Health and Nutrition Sciences at Brooklyn College found that heart attack sufferers who owned a dog were eight-times more likely to survive one year after the heart attack. 8 Other studies show that patients with cardiovascular disease that own a dog are more active, exercise more and have lower serum cholesterol.
5. ALZHEIMER PATIENTS EAT MORE WHILE WATCHING FISH: Alan Beck, D.V.M, from the Center for the Human-Animal bond, School of Veterinary Medicine, Purdue University, found that Alzheimer’s patients who ate meals in view of an aquarium ate 21-percent more and gained 1.65 pounds over 16 weeks compared with control groups. 9 Fish-watchers also required less nutritional supplementation during this time, which resulted in health care cost savings.
6. CHILDREN WITH PETS HAVE HIGHER READING SCORES AND MORE EMPATHY: Sociologist Robert Poresky, Kansas State University, found children who spend time with their companion animals are more empathetic and learn responsibility earlier. They may even have higher IQs than children without pets. The R.E.A.D. program, run by the Intermountain Therapy Animals in Salt Lake City, Utah, reports that children who have trouble reading drastically improve when they read to dogs. They say animals can be ideal reading companions because they help increase relaxation, are attentive listeners, and they don’t judge or criticize.10
7. PETS HELP SENIORS: P. Raina, Ph.D., from the University of Guelph, Ontario, Canada reports that seniors with pets can perform simple daily living tasks, such as getting in and out of bed, eating, bathing, and dressing, better than non-pet owners. 11
Using the UCLA loneliness scale, William Banks, M.D., of the Veterans Affairs Medical Center in St. Louis, shows a 30-minute exposure to a companion animal significantly reduces loneliness in residents of long-term care facilities. 12
ANIMAL ORGANS AND CELLS USED FOR HUMAN HEALTH
Each day in the United States, 13 people die while waiting for an organ transplant. Over 4,900 patients on organ waiting lists in the United States alone could have been saved last year if organs were available. Many other patients have no hope of transplantation because their age or other health conditions preclude them from organ transplant waiting lists.
While the number of donated organs remains fixed, the demand for transplant operations is increasing by about 15 percent each year. The demand is fueled by an enhanced success rate and decreased acute rejection rates. Proponents of xenotransplantation hope that it may soon be one of modern medicine's alternatives to help solve this critical problem. Pigs are considered the most likely organ transplant donors for humans because of their similar sized organs and their breeding efficiency.
Researchers at Immerge Bio therapeutics and the University of Missouri, and those at PPL, the company that cloned the sheep Dolly aimed to circumvent the overwhelming problem of acute rejection. They created pigs deficient in the gene coding for alpha-1,3-galactosyltransferase, the key sugar molecule responsible for triggering acute rejection. Human antibodies attach to this molecule on the pig cells and kill them. Eliminating the sugar molecule should eliminate the rejection. Scientists agree that the field would definitely be moved forward if this proves to stop the rejection.
A key safety concern for scientists is the transmission of porcine endogenous retrovirus (PERV) that can infect human cells in laboratory tests. The pigs developed by Immerge and PPL have created a pig that fails to produce PERV, another hurdle overcome in the road to potential pig donors. Xenotransplantation is not just about transplanting organs. Researchers at Diacrin, a biotechnology company in Charlestown, Mass., have used cellular transplants to treat Parkinson’s disease patients. 1 Patients such as Jim Finn improved to the point he could do things he thought were lost forever - walk without a cane, climb stairs, buy food, give speeches and drive a car. Although improvement is seen in patients, there is no significant difference in patients treated with fetal pig cells and those who underwent a ‘sham’ surgery.
Other xenocellular therapies in the research stages include work by J. Wright, M.D., Ph.D., at Dalhousie University Faculty of Medicine, Halifax, Nova Scotia, Canada. He studies the use of pancreatic islet cells from Tilapia fish to treat diabetic patients. 2 Epicel, a product licensed by Genzyme, Cambridge, Mass., is used to treat severe burns. It is a process to grow a patient’s cells from the unburned area on a ‘feeder’ layer of mouse cells and then transplant them onto the burn site. 3
Researchers from Nextran, a division of Baxter Healthcare in Deerfield, Ill, have used pig livers as an external support system for patients awaiting human livers. Four cases have been successful in ‘bridging’ patients until human livers were available.4
Circe Biomedical, a private biomedical company in Lexington, Mass, has developed a liver support system that integrates viable pig liver cells with biocompatible membranes into an external bioartificial liver assist system. They are also developing a similar bioartificial pancreas. 5
Despite the advances in the field, not all are proponents of xenotransplantation. Alix Fano, founder of the Campaign for Responsible Transplantation (CRT), vehemently disagrees with any form of xenotransplantation. CRT members believe that xenotransplantation poses a grave danger to human health because of the risk of transferring deadly animal viruses to the human population. They cite the recent SARS outbreak as a potential example, citing early reports that the virus may have originated from pigs. They believe there are safer and more cost-effective ways to resolve the alleged shortage of human organs for transplantation that are not being adequately explored. 6
Fano says there are also regulatory issues. Informed consent regulations revealed that patients participating in xeno trials could withdraw from such trials and from programs that monitor them for infectious pig viruses. Food and Drug Administration guidelines call for lifetime monitoring for viruses in these patients but forced compliance is illegal, creating a frightening public health problem. Moreover, current laws do not require informed consent from third parties such as health care workers or intimate contacts.
CRT's international coalition includes more than 90 public interest groups and is supported by physicians, scientists, veterinarians, scholars, lawyers and concerned laypersons. CRT is seeking a total ban on xenotransplantation.
REFERENCES AND CONTACTS
MORE THAN MAN’S BEST FRIEND
- Pickel D, Cognetta A, Manuey G, Walker D, Hall S, Walker J. “Preliminary Evidence of Canine Olfactory Detection of Melanoma.” Poster presentation at the April 2001 meetings of the Association for Chemoreception Sciences.
- Williams H, Pembroke A. “Sniffer Dogs in the Melanoma Clinic?” The Lancet, 1989;734.
James Walker, Ph. D.
Director Sensory Research Institute
Florida State University, Tallahassee
Paul Waggoner, Ph. D.
Armand Cognetta, M.D.
Dr. Barbara Sommerville
PETS AND PEOPLE AND PETS HELP AND HEAL
- Cusack O, Smith E. Pets and the Elderly -- the Therapeutic Bond. New York: The Haworth Press, 1984:13-16.
- Becker M. The Healing Power of Pets. New York: Hyperion; 2002.
- Allen K, Shykoff BE, Izzo JL. “Pet Ownership, But Not ACE Inhibitor Therapy, Blunts Home Blood Pressure Responses to Mental Stress.” Hypert, 2001;38:815-820.
- Allen K, Blascovich J, Mendes WB. “Cardiovascular Reactivity and the Presence of Pets, Friends, and Spouses: The Truth About Cats and Dogs.” Pysch Med, 2002;64:727-739.
- Odendaal JS, Meintjes RA. “Neurophysiological Correlates of Affiliative Behavior Between Humans and Dogs.” Vet J, 2003;165:296-301.
- Friedman E, Katcher AH, Lynch JJ, Thomas SA. “Animal Companions and One-year Survival of Patients After Discharge from a Coronary Care Unit.” Public Health Reports, 1980;95:307-312.
- Edwards NE, Beck AM. “Animal-Assisted Therapy and Nutrition in Alzheimer’s Disease.” West J. Nurs Res, 2002;24(6):697-712.
- Intermountain Therapy Animals, www.therapyanimal.org
- Raina P, Waltner-Toews D, Bonnett B, Woodward C, Abernathy T. “Influence of Companion Animals on the Physical and Psychological Health of Older People: An Analysis of a One-Year Longitudinal Study.” J Am Geriatr Soc., 1999;47(3):323-329.
- Banks MR, Banks WA. “The Effects of Animal-Assisted Therapy on Loneliness in an Elderly Population in Long-Term Care Facilities.” J Gerontol A Biol Sci Med Sci, 2002;57(7):M428-432.
Karen Allen, Ph. D.
State University of New York at Buffalo
Rebecca Johnson, RN, Ph. D.
University of Missouri
Nalini Saligram, Ph. D.
Alan Beck, DVM
Purdue University School of Veterinary Medicine
Sandra Barker, Ph. D
Director, Center for Human-Animal Interaction
School of Medicine
Virginia Commonwealth University
Marty Becker, DVM
Edward Creagan, M.D.
Professor, Mayo Clinic
ANIMAL ORGANS AND CELLS USED FOR HUMAN HEALTH
Jon Allan, Ph. D
PPL Therapeutics Inc.
Alix Fano, CRT