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Oscar D. Ratnoff (1916-2008)

Oscar Ratnoff, MD

Oscar D. Ratnoff, MD, we might presume, stood in his office in late 1964 with his biochemist colleague, Earl Davie, at Case Western Reserve University and in a moment of chalkboard brilliance, devised the coagulation waterfall, published later that year in the journal, Science. His observations, along with those of Robert Macfarlane, also published in 1964 in Nature, provided the guiding light for research and education into the clotting process for decades to come.

Dr. Ratnoff, by his own hand, used painstaking efforts to partially purify clotting factors, and then used blood products from patients with deficits in one or more factors to establish mixing experiments and deduced the complexity of blood clotting by simple glass tube experiments timed with a stopwatch. For those of us lucky enough to have laboratories nearby, we watched patients come to his research office, and we provided countless blood samples as healthy donors until we turned 40, at which time he recognized that our own clotting waterfalls became more complex and were perhaps not suitable as controls.

The son of a New York general practitioner, Dr. Ratnoff was trained, first at Columbia College of Physicians and Surgeons, then at Johns Hopkins, Harvard Medical School, and Montefiore Hospital in New York, before coming in 1952 to what are now Case Western Reserve University School of Medicine and University Hospitals, Case Medical Center. Read more...