Nova Scotia Firsts
Remarkable health science advances made by Nova Scotians.
The Elucidation of the Chemical Structure of Genes: Dr. Oswald Avery:
Dr. Oswald Avery was born in Halifax in 1877 the son of Rev. Joseph Avery. Oswald attended Halifax Schools until he was ten years of age at which time he moved to New York with his parents. He was educated at Colgate University (AB., 1900, NS Columbia (MD., 1904).He pursued medical research at the Hoagland Laboratory in Brooklyn from 1906 to 1913 and, in the latter year, joined the Rockefeller Institute Hospital in New York as a Bacteriologist. He remained at the Rockefeller until 1955 and died in Nashville that same year. His research on pneumococcus made him known internationally. In 1918 during the Spanish Influenza Dr. William Welch of John Hopkins visited Avery at the Rockefeller and urged him to develop a vaccine to combat the influenza. His most major achievement in medical research, however, was described in his published paper in 1944 in which he announced that DNA was the purveyor of genetic information. It has been said that the elucidation of the chemical structure of genes by Oswald Avery, the introduction of quantum theory by Max Planck, and Einstein’s pronouncement of the theory of relativity, are the three land-mark events in science during the 20th century. The Royal Society of London awarded him the Copley Medal in 1945 and the Association of American Physicians awarded him the Kober Medal in 1947. (By Dr. Allan Marble, President, AHSAMNS and Chair, Medical History Society of Nova Scotia)
Chloroform Manufactured by a Nova Scotian Pharmacist in 1848:
Within a few months of Dr. James Simpson pioneering the use of chloroform as an anesthetic in Edinburgh, in 1847, J.D.B. Fraser, a pharmacist in Pictou, Nova Scotia, prepared chloroform that was used to anesthetize a man while he had his leg surgically amputated. Several weeks later, Fraser administered chloroform to his wife during the birth of their seventh child. Mr. Fraser had a thriving drug store, held political positions and pursued various business interests including a stone quarry, a stage coach company and coal mining.
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 anesthetic 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.
Liposomes as Carriers for Enhancing Skin Delivery of Drugs:
Dr. Michael Mezei was a faculty member at the College of Pharmacy, Dalhousie University (1967-1993) and Professor Emeritus (1993-1997). During the late 1970s he conducted research on liposomes as a drug delivery system for drugs on the skin. (Liposomes are phospholipid vesicles which can be used to encapsulate drugs whether they are hydrophilic, lipophilic or amphiphilic.) In 1980, Dr. Mezei and his graduate student, Lakshmi Gulasekharam published research in Life Sciences that proved that liposomal triamcinolone acetonide, when compared to control lotion, provided increased drug deposition in the epidermis and dermis. In addition, they showed that systemic concentrations of the drug were significantly reduced, thus decreasing the risk of side effects. Many publications on liposomes from other research labs followed, with Dr. Mezei’s research leading the way.