Monday, 20 February 2012

Animal Sentinels: “Biosensors”


Tonight, (14 Feb.) Jacqueline Bailey kicked off the One Health session by presenting information on animal sentinels and their relation to biological sensors. Jacqueline Bailey is an undergraduate at Meredith college pursuing a Bachelors of Science in Biology and an International Studies minor. Her initial interest was in humanities and social sciences, but after receiving a grant to fund a community tree orchard in Mauritania, West Africa her attention turned to the sciences.  After she returned from Africa, she ran the mosquito lab of Dr. Larry Grimes and conducted some of her own research.  She hopes to join the graduate program at UNC Gillings School for Global Public Health.

Jacqueline began with a brief history of how humans have utilized animals to detect specific substances such as the mine canaries as early warning systems for carbon monoxide and methane.  More recently, we have realized that dogs are capable of detecting the onset of seizures and the volatile compounds in tumors associated with cancer due to their extensive olfactory system. Jacqueline shared that dogs have an astonishing 125-150 million scent receptors compared to the 10-15 million that humans have. To elaborate on this point, Jacqueline shared a news story presented on NBC that covered the results of a study that proved dogs could detect lung cancer from smelling the breath of lung cancer patients.  This was a great discovery since lung cancer is very difficult to diagnose early.

Jacqueline Bailey discussing animals as biosensors.

The latter part of the presentation focused on the basic processes of associative learning and the new research occurring with Microplitis croceipes as biological sensors.  Jacqueline discussed Karel vonFrisch’s research on the communication methods of the honeybee which marked the beginning knowledge of associated learning in insects. Over the past few decades Dr. Lewis’s lab has further developed this research with the use of Microplitis croceipes. It appears that dogs and Microplitis croceipes can both be classically conditioned, but unlike dogs, these insects can be trained in minutes.  Furthermore, the process is relatively simple: the insect is exposed to a scent for ten seconds, rewarded with food, and the process is repeated three times.  Realizing the potential use of these wasps, Dr. Lewis teamed up with Dr. Glen Rains to explore the possible uses.

Fortunately, Jacqueline shared that the discoveries were very positive, concluding that Microplitis croceipes can be trained to recognize almost anything, including the detection of volatile compounds in humans. In order to further the use of these insects, the team created the Wasp Hound, which allowed the researchers to contain the Microplitis croceipes in a handheld device that was linked up into a computer. A software program called the Visual Cortex then detects the response of the insect by taking five frames of video per second where the food-searching behavior of the insects is monitored.  In the Wasp Hound there is a small hole where the scent is fanned through, and if the Microplitis croceipes recognize the odor they will crowd to the center.  With the potential to detect volatile compounds, bed bugs, Malaria, TB, and infectious diseases, this technology has a bright future. In fact, Jacqueline announced that Bennett Aerospace is interested in marketing the technology to hotel businesses because the wasps can detect bed bugs. Dr. Brandon Conover, Director of Research at Bennett Aerospace, further explained the plan to put the device into market under the name Smart Hound. Additionally, further research is underway to create a more efficient and technologically advanced Smart Hound that will have better qualitative and quantitative assessment.

Post authored by Madison Roche, NCSU undergraduate majoring in Biology