Jan Janský () (3 April 1873 in

Smíchov Smíchov () is (since 1909) a district of Prague, the capital of the Czech Republic, and is part of Prague 5. It is on the west bank of the Vltava river. History Between 1945 and 1989, the district contained a monument dedicated to Soviet ta ...

, now

Prague Prague ( ; cs, Praha ; german: Prag, ; la, Praga) is the capital and List of cities in the Czech Republic, largest city in the Czech Republic, and the historical capital of Bohemia. On the Vltava river, Prague is home to about 1.3 milli ...

– 8 September 1921 in

Černošice Černošice () is a town in Prague-West District in the Central Bohemian Region of the Czech Republic. It has about 7,400 inhabitants. The town is part of the Prague metropolitan area. It lies southwest of Prague, on the Berounka River. History ...

, near Prague) was a

Czech Czech may refer to: * Anything from or related to the Czech Republic, a country in Europe ** Czech language ** Czechs, the people of the area ** Czech culture ** Czech cuisine * One of three mythical brothers, Lech, Czech, and Rus' Places * Czech, ...

serologist,

neurologist Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal c ...

and psychiatrist. He is credited with the classification of

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...

into four

types Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type In computer science and computer programming, a data type (or simply type) is a set of possible values and a set of allo ...

(I, II, III, IV).Book "The Neuronal Ceroid Lipofuscinoses" Author Sara Mole, Ruth .Williams, Hans Goebel. Date Mar. 10, 2011. https://books.google.ca/books?id=iViwAAAAQBAJ&lpg=PA12&ots=GmUT7yagrA&dq=%22Hematological%20study%20of%20psychotics%22%20Jan%20Jansk%C3%BD&pg=PA12#v=onepage&q=%22Hematological%20study%20of%20psychotics%22%20Jan%20Jansk%C3%BD&f=false Janský studied

medicine Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pr ...

at Charles University in Prague. From 1899, he worked in the Psychiatric Clinic in Prague. In 1914, he was named

professor Professor (commonly abbreviated as Prof.) is an academic rank at universities and other post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin as a "person who professes". Professors ...

. During

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

Janský served two years as a doctor at the front until a heart attack disabled him. After the war he worked as a

neuropsychiatrist Neuropsychiatry or Organic Psychiatry is a branch of medicine that deals with psychiatry as it relates to neurology, in an effort to understand and attribute behavior to the interaction of neurobiology and social psychology factors. Within neuro ...

in a military Hospital (''Vojenská nemocnice''). He had angina pectoralis and died of

ischaemic heart disease Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of atherosclerotic pla ...

. Janský was also a proponent of voluntary blood donations.

Classification

Through his psychiatric research, Janský tried to find a correlation between mental diseases and blood diseases. He found no such correlation existed and published a study, ''Hematologická studie u psychotiků'' (1907, ''Hematological study of psychotics''), in which he classified blood into four groups, I, II, III, and IV. (At the time, Janský was unaware of the work of

Karl Landsteiner Karl Landsteiner (; 14 June 1868 – 26 June 1943) was an Austrian-born American biologist, physician, and immunologist. He distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from ...

, whose discovery of the A, B, and O blood types earned him the

Nobel Prize in Physiology or Medicine The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, accord ...

in 1930.) At the time Janský's discovery passed almost unnoticed. In 1921 an American medical commission acknowledged Janský's classification. A similar classification was described by William Lorenzo Moss, except the I and IV of Moss were the opposite to that of Janský's, leading to confusion in

blood transfusion Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but mo ...

until the use of A, B and O became standard.

Legacy

* Frequent voluntary blood donors in the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

and

Slovakia Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the s ...

are awarded with Janský medal (''Janského plaketa''). * The Secret of Blood, a 1953 Czechoslovak film about his discovery.

References

External links

Biography (in Czech)
{{DEFAULTSORT:Jansky, Jan Czech neurologists Serologists Charles University alumni Charles University faculty 1873 births 1921 deaths Czech psychiatrists Scientists from Prague Deaths from coronary artery disease