On May 31, Children's Hospital Boston held its seventh annual Research Day, highlighting the work of residents, clinical fellows and postdoctoral fellows. In all, 111 posters, representing 26 departments and divisions, filled the atria of the Karp building's 7th to 11th floors.
As last year, eight researchers were chosen to give oral presentations at Surgical or Medical Grand Rounds. Three presenters, all fellows, won prizes: Eva-Jasmin Freyschmidt, PhD, (Immunology) for developing a mouse model that may explain why people with eczema suffer severe complications from smallpox vaccination; Shaun Kunisaki, MD, (Surgery) for creating tissue-engineered cartilage grafts to reconstruct missing or defective tracheas; and Kelly Scribner, PhD, (Endocrinology) for showing in mice that eating slowly-absorbed carbohydrates (like those in whole grains) instead of refined carbs can reduce body fat content and prevent fatty liver disease.
New this year were House Officer Development Awards of $7,500 each. They were awarded to Neurology fellow Shafali Spurling Jeste, MD, for a project on early screening for autism in tuberous sclerosis complex; Medicine resident Sallie Permar MD, PhD, for research in monkeys on HIV transmission through breastfeeding; and Psychiatry fellow Patricia Ibeziako, MD, for a project on overcoming barriers to mental health care.¬ÝThere were 18 applicants this year; Robert Holzman MD, president of the Medical Staff, says next year's grants will be raised to $10,000.
Research Day was sponsored by the Medical Staff Organization and organized by the Research Faculty Council and the Office of Fellowship Training.
Patients with disrupted electrical conduction in their hearts, known as complete heart block, currently receive pacemakers, but these devices often fail over time, particularly in infants and small children. Researchers led by cell biologist Douglas Cowan, PhD, of Children's Department of Anesthesiology, Perioperative and Pain Medicine, have now taken preliminary steps toward engineering electrically conductive tissue that would substitute for a pacemaker. Although the studies were in rats, the tissue-engineered implants could potentially be made from a patient's own muscle cells in the future.
In normal hearts, electrical impulses move first through the upper chambers (atria), then pause at the atrioventricular (AV) node. After a short delay, the AV node releases the impulses, and the lower chambers (ventricles) contract. In this way, heartbeats are synchronized. But in complete heart block, electrical signals cannot pass from the atria to the ventricles, leading to severe rhythm disturbances and heart failure.
Cowan's team, including first author Yeong-Hoon Choi, MD, in the Department of Cardiac Surgery, wanted to create a biological substitute for the AV node. Using special cells, called myoblasts, taken from skeletal muscle, they created a three-dimensional bit of living, electrically conducting tissue. When surgically implanted into rats, the tissue integrated with the surrounding heart tissue and electrically coupled to neighboring heart cells, establishing a new conduction pathway in nearly a third of the rats. The implants kept functioning throughout the animals' lifespan (about three years).
Cowan and his team are now working with a large-animal model that more closely simulates pediatric heart block and are refining their techniques to create grafts that behave more like a natural AV node. The study appears in the July issue of the American Journal of Pathology.