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Nova Scotia Firsts

The Introduction of Curare as a Muscle Relaxant during Surgery

Dr. Enid Johnson MacLeod was a medical graduate from Dalhousie in 1937. During her residency training in Montreal she and her mentor, Dr. Harold Griffith, investigated the properties of curare. Curare is extracted from some types of woody plants in South America and was well known to have paralyzing properties and had been used by the indigenous people of Central and South America for centuries to asphyxiate the respiratory muscles of their prey. The indigenous people would dip their darts or arrows in curare and shoot the darts at their prey thus paralyzing them so that they could be captured. Drs MacLeod and Griffith were the first to carry out an extensive study of the properties of curare and its effectiveness as a muscle relaxant  during surgery. Their work received international attention in 1942 when they reported on the first surgical operation in which curare was used successfully as a muscle relaxant. The introduction of curare as an anaesthetic adjunct is considered by many as one of the most crucial developments in medicine in the past century.

Recognition for Major Contributions to the Understanding of Evolutionary Biology

For the past fifty years, Dr. Ford Doolittle, an Emeritus Professor in Biochemistry and Molecular Biology at Dalhousie University, has been researching and publishing papers on various aspects of evolutionary biology. His papers on the subject have appeared mainly in the prestigious journals Science and Nature. Dr. Doolittle has made significant contributions to the study of cyanobacteria (bacteria that obtain their energy through photosynthesis) and has found evidence of the endosymbiont origins of chloroplasts (specialized subunits of plant cells). He has also shown the importance of horizontal gene transfer in the evolution of prokarytote (single-celled organisms). For these and other original research contributions to evolutionary biology, Dr. Doolittle was awarded the prestigious Herzberg Medal in 2014, Canada’s top Scientific Prize.

 

Explanation of Suture Line Disruption following the Implantation of Synthetic Vascular Grafts

In 1973, Dr. C. Edwin Kinley, Dr. Allan E. Marble, and research associates, discovered that the diameter of large arteries in the cardiovascular system changes by as much as ten percent during the cardiac cycle rather than by only two or three percent as was previously reported. This large diameter change was observed from 35mm films which had been made using cine-angiography during routine diagnostic procedures. It was also observed that the diameter of synthetic vascular grafts does not change during the cardiac cycle of pressures. These observations provided an explanation of why there had been several cases of disruption or failure of the suture line connecting a host artery to a vascular graft post implantation. Using computer modelling studies the magnitude of the stresses at the suture line due to this extreme difference in distensibility was calculated and indicated that there was a high probability that suture line disruption would take place. These observations and results were reported by Drs Kinley and Marble in the Journal of Cardiovascular Research and the American Journal of Physiology and they were invited to present their findings at a special Symposium on Synthetic Vascular Grafts at the National Institutes of Health in Washington. In order to prevent suture line failure, Drs Kinley and Marble recommended that future vascular grafts be designed to have the same distensibility as host arteries.      

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