Hendrik Coenraad Hemker

Hendrik Coenraad "Coen" Hemker (born 21 July 1934) is a Dutch biochemist and academic administrator. He was one of the founders of Maastricht University and was its rector magnificus from 1982 to 1984. He was a professor of biochemistry from 1975 until 1999. In his research he has mainly studied thrombosis and hemostasis.

Early life and career Hemker was born on 21 July 1934 in Amsterdam. With his mother being a heart patient and his father spending a lot of time on his hobbies, Hemker frequently looked after his four younger brothers. He subsequently wanted to study pediatrics but was advised by Dutch pediatrician to study biochemistry for a year. Hemker obtained his medical degree from the University of Amsterdam in 1959. Academically he performed well and he was asked to continue his studies so he could obtain a PhD. By this time he thoroughly liked performing research and accepted the offer.

Hemker subsequently started his specialist training to become a pediatrician but stopped as he preferred doing research. He was then hired as a researcher at the hemostasis and thrombosis department of Leiden University. While in this position he was sent to Oxford for further training where he met Robert Gwyn Macfarlane. Macfarlane had developed a first theory of coagulation. Hemker doubted the validity of the theory and thought one of the enzymes played a different role. The two men found Hemker's idea was correct and they subsequently published their findings in Nature. Hemker became a lector of cardiology and professor of internal medicine at Leiden University in 1968. The group was responsible for the forming of the eight faculty of medicine in the Netherlands, but when their work commenced the urgent need for the faculty was already diminished which led to the search for a different profile for the university as compared to others. This was found in first line care, family medicine, and a new education concept. Hemker found that research did not receive sufficient attention. During his time at Maastricht problem-based learning was considered innovative at the institute, although Hemker was initially positive about this he later became neutral to negative on the approach. Between 1976 and 1985 Hemker was concurrently working as an unpaid part-time professor of biochemistry at Leiden University. In 2009 a lecture hall at Maastricht University was named after him. In the same year that a similar mechanism describes how the antihemophilic factors (Factors VIIa and IXa) act. The detailed enzyme kinetics of these interactions was investigated later in collaboration with Rosing, Tans and Van Dieijen. The role of blood platelets in these processes was investigated in his lab by the groups of Zwaal and Béguin. A second line of research is the mode of action of antithrombotic drugs, both vitamin K antagonists and heparins. A third main subject developed in collaboration with S.Béguin, is the invention of an automated thrombin generation test as sensitive probe for the function of the hemostatic power and thrombotic tendency of the blood. Hemker has more than 500 scientific publications to his name and holds several dozen patents. He was the founder of the company Synapse, at which he continued to work after his retirement from Maastricht University.

Awards and honours Hemker was the winner of the 1968 Prix Européen Ganassini for his research on vitamin K coagulants. Hemker was elected a member of the Royal Netherlands Academy of Arts and Sciences in 1987. In the same year he was named a commander of the Ordre des Palmes académiques. He became a Chevalier in the Legion of Honour in 1990. In 2000 he was made a Knight of the Order of the Netherlands Lion. In 2001 Hemker became a foreign member of the French Académie Nationale de Médecine. He was promoted to Officier in the Legion of Honour in 2011. In 2019 Hemker won the Dr. J.G.H. Tans Medal, the highest award of Maastricht University.

Personal life Hemker's wife is a psychiatrist and psychoanalyst. During the late 1980s Hemker suffered from severe ulcerative colitis, which led to him losing 20 kilograms and it nearly killed him. In an operation his large intestine was removed and Hemker subsequently recovered. Hemker wrote a cook book with chef Jacques Zeguers.