Of Note

Winter 2018

"D" Way to Teach









Click here to read a Q&A with two Pitt Med favorites who retired in June—
Georgia Duker and Susan Dunmire.

(Photos: Courtesy Duker and Dunmire. Photo illustration: EGC/APK) 

Hatching Physician-Scientists 


Advancing medicine is not going to happen without doctors who also do research. Yet the pipeline for physician-scientists is “uncertain,” as a July 3 editorial in JAMA noted. Pitt Med has taken a number of steps through the years to address this shortage; the latest is its Physician Scientist Incubator program. Pitt Med will institute the program with $2.5 million from the Burroughs Wellcome Fund, a $2.5 million grant from UPMC, and a $250,000 grant from the University. 

Juggling research and patient care can be tricky for young clinicians, and federal funding uncertainties make the physician-scientist track more difficult. The incubator program will enroll 21 residents in its first five years and help fund their research. It also will connect residents with successful physician-scientist mentors. 
Samer Tohme, a general surgery resident who helped organize the program, says, “How can we attract and try to find those people who are interested and keep them interested? Give them all support to be able to maintain their potential and achieve all they want to.”  

Weakened Associations


One approach to keeping a person struggling with addiction away from relapse is to weaken environmental associations. It’s a bit like teaching arachnophobes how to reduce their fear of spiders. Doctors can safely expose patients to the cues that remind them of encounters with spiders; they can do the same for encounters with drug use. Patients eventually learn to experience those cues without fear, craving, or whatever response is targeted.

Mary Torregrossa, associate professor of psychiatry at Pitt, uses a similar method in a rat model for cocaine addiction. She determines the neural circuits responsible for mediating the ability to reduce cravings, and her team uses optogenetics (a neuromodulation method where light controls cells) to mimic the effects of exposure therapy. “We identify the part of the brain where cocaine-related cues are learned,” says Torregrossa. “We stimulated this brain circuit in a way that reduced the strength of the cocaine memory, and we were able to prevent relapse.” A paper on the study is in peer review.
Torregrossa imagines doctors one day using a similar method to treat addiction. Doctors would replace optogenetics with another type of deep brain stimulation to weaken drug-associated memories.

A Tissue-level Superpower


(Illustration: Getty Images)










When a salamander loses its tail, it builds another one beautifully. But a lizard amputee? Not so much. “It doesn’t get anything right,” says Thomas Lozito, PhD assistant professor of orthopaedic surgery. “There’s no bone; the skeleton is completely cartilaginous, just tubes within tubes,” he adds. Lozito and his research team discovered the reason for this difference. During regeneration, salamanders can produce multiple types of cells from neural stem cells, a process called differentiation. Lizards, meanwhile, can only produce a limited range of cell types.

In an article published in the Proceedings of the National Academy of Sciences in August, Lozito identifies the mechanism responsible for enabling salamander cells to differentiate during regeneration: a gene playfully called the hedgehog gene. Lozito and Pitt coauthors Ricardo Londono, an MD/PhD, Megan Hudnall, and Rocky Tuan, a PhD (who is now vice chancellor of the Chinese University of Hong Kong), also discovered that the hedgehog gene will retain its ability to cause differentiation when implanted into a lizard’s tail stump. This discovery could have implications for healing human wounds. Lizard genomes resemble the genomes of mammals more than they do those of salamanders.
“Our approach is to identify animal superpowers that mammals don’t have,” Lozito explains. 
While still a long way from developing a technique to regrow a full limb, Lozito’s discovery could one day help manage pain and facilitate prosthesis attachment. 
These are “baby steps,” Lozito says. “But if you can just prevent scar formation and a little bit of tissue growth, that’s significant.”  

Gone Gene Gone


(Photo: R. Bonde, U.S. Geological Survey)











In August, Pitt’s Nathan Clark published research results in Science that change our understanding of the effects of certain neurotoxins in marine environments. Clark is a PhD associate professor of computational and systems biology specializing in evolutionary genomics. His team compared the genomes of aquatic mammals, like dolphins, manatees, and sea lions, with their terrestrial cousins. In doing so, the group discovered that the PON1 (paraoxonase 1) gene—which defends humans and other land mammals against toxic organophosphates (a kind of pesticide commonly used in agriculture)—has been lost through the process of evolution. Without this gene, marine mammals have no way to combat the paralysis and brain damage associated with the pesticides.  

No federal laws currently restrict these pesticides from contaminating agricultural runoff, and that may be a contributing factor in the unusually high mortality rates of certain marine mammals in the Southeastern United States. “The biggest implication is species conservation,” says Clark. “A lot of aquatic animals live right below these agricultural fields where these pesticides are being used.” It is Clark’s hope that this discovery will prompt the Environmental Protection Agency to begin eliminating the use of organophosphates to protect vulnerable marine life. 

Smooth Ride

(Photo: UPMC Children’s Hospital of Pittsburgh)










When you hear an ambulance, you move aside and turn to look. Those are the rules! UPMC Children’s Hospital of Pittsburgh has a new ambulance that will make people do a double take. It’s built for transporting critically ill babies and children and has a colorful, eye-catching design. The ambulance will travel within a 150-mile radius of Pittsburgh; its features include a backup generator, state-of-the-art medical gas supply, Wi-Fi, a camera system, safety seating for the crew and parents, and a hydraulic lift. “It’s designed to give patients a smoother ride,” says neonatologist Melissa Riley. “And its accessibility means a faster departure, which leads to a faster response time.”

Doctor Basketball

Doc Carlson (Photo: 1935 Owl yearbook.)

Can you imagine if it were reported that Jeff Capel, Pitt’s men’s basketball coach, fed his players ice cream at halftime? What a scoop! Well, that’s what Henry Clifford Carlson, better known as Doc Carlson, did during the Depression. Carlson (MD ’20) coached Pitt to two national championships; in September, the man known as the “Clown Prince of Basketball” was honored posthumously when Pitt inducted its inaugural Athletics Hall of Fame class. Carlson, a physician who treated all of his players from 1922 to 1953 (including a whole team of med students), entered the Hall with such legends as Dan Marino, Mike Ditka, and Tony Dorsett.