This article will talk about one of the greatest Czechs in history - Jan Purkinje. This man was engaged in research in the field of biology and medicine, thereby leaving a deep mark not only in the history of his homeland, but throughout the world.
Early years and first successes
Jan Purkinje (years of life: December 17, 1787 - July 28, 1869) was born in Libochovice, which was then on the territory of Austria-Hungary. His father was the manager of the estate. After the death of his father, when Jan was 6 years old, he was called to become a priest. These plans, along with his own poverty, led to him being expelled from one Piarist monastery school to another from the age of 10.
He studied at the institute in Litomysl and then in Prague. For some time he earned money as a teacher of rich children. In 1813 he entered the medical faculty of the University of Prague and graduated in 1818. Then received his doctorate in 1819, after a dissertation on subjectivevisual phenomena.
Through introspection, he established that visual sensations are caused by the activity of the brain and its connection with the eye, so that they cannot be caused by external stimulation. Purkinje became a dissector, a man with the special task of preparing for a dissection demonstration, and an assistant at the Institute of Physiology at the University of Prague, but he did not have the opportunity to conduct his own experiments.
He did research on the phenomena of vertigo, still relying on the introspection method at the Prague Carousel Fair. He noticed that the direction of vertigo did not depend on the direction of rotation, but on the position of the head in relation to the body. In addition, he described the phenomenon of nystagmus, a visual condition in which the eyes make repetitive, uncontrollable movements, resulting in decreased vision and depth of perception, and can affect balance and coordination.
Purkinje also analyzed the physiological effects that occur after the use of certain drugs, including camphor, opium, foxglove and belladonna. He experimented on himself, sometimes going to dangerous extremes. He noticed that using one drug after another seemed to increase the effect of the first one.
He observed, nearly 30 years before Helmholtz, the inside of the eye in light reflected back into it by concave lenses. He noticed some differences in color detection in dim light compared to daylight. This phenomenon was then called the "Purkinje phenomenon".
Currently it isdue to differential excitation of rods and cones. He also highlighted the importance of fingerprints in solving crimes, an idea that was completely new at the time.
Activities in Breslau
Purkinje applied for a teaching position at many universities in the Austrian Empire, but was not accepted. He was Czech and university officials preferred to promote German citizens to academic positions.
Fortunately, his doctoral dissertation was well received and attracted the attention of Goethe, who was interested in the same subject. With the strong support of Goethe and Alexander von Humboldt, in 1823 he was offered a position as professor of physiology at the University of Breslau. Thus began the most fruitful period of his career.
Purkinje's success at Breslau was based on superior equipment and new methods for preparing research material. He had a very modern and precise microscope and microtome. He was the first to establish that the entire body is made up of cells. He did it 2 years before T. Schwann.
Paradoxically, in the history of science, the latter is more often associated with this discovery. Perhaps this is because Purkinje's main interest was the inside of the cell, while Schwann was describing the cell membrane and was the first to use the word "cell".
Undoubtedly, Purkinje was the first to observe and describe the cell nucleus. He also noticed that cells are the structural components of animals and plants. He introduced the terms "cell protoplasm" and "plasma" into the scientific language.blood".
Methods of the time allowed Jan Purkinje to conduct neurological research. In 1837, he published a paper on ganglion cells in the brain, spinal cord, and cerebellum. He was the first to notice the importance of the gray matter of the brain. Before its discovery, scientists thought that only white matter and nerves mattered.
He emphasized that these cells are the centers of the nervous system and nerve fibers, like wires that transmit energy from them to the whole body. He accurately described cells in the middle layer of the cerebellum with tree-branching dendrites. They were then called "Purkinje cells".
The scientist's discoveries were often published in the dissertations of his assistants. He supervised the doctoral dissertation of David Rosenthal (1821-1875): they jointly discovered that nerves have fibers inside and analyzed their number in spinal and cranial nerves.
Purkinje also found that sleep is caused by a decrease in external impulses. He conducted research by influencing the partially destroyed animal brain with needles, being one of the first researchers to use this method. For many years, Jan Purkinje used a special swivel chair and recorded all the optical effects associated with movement and the physiological signs that accompany dizziness.
He did research in which he directed the flow of galvanic current through his own skull and observed the reaction of the brain. He determined the movement of cilia in the reproductive and respiratory systems, and ultimately inventricles of the brain. In 1839, Jan Purkinje discovered the fibrous tissue that transmits electrical impulses from the atrioventricular node to the ventricles of the heart. Today they are called Purkinje fibers.
Educational activities
In 1839, Jan Purkinje opened the physiological institute in Breslau, which was the first such institution in the world. He became Dean of the Faculty of Medicine, having been elected to this position four times in a row. In 1850 he became professor of physiology at the University of Prague. There he focused on returning to the use of the Czech language instead of German in university activities.
He found a significant reduction in the sensitivity of the human eye to dim red light compared to similar blue light. He published two books, "Observations and Experiments Investigating the Physiology of the Senses" and "New Subjective Reports on Vision", which contributed to the emergence of the science of experimental psychology.
He created the world's first chair of physiology at the University of Breslau in Prussia (now Wroclaw, Poland) in 1839 and the world's first official physiological laboratory in 1842. Here he was the founder of the Literary Slavonic Society.
The most famous discoveries
Jan Purkinje is best known for:
- His discovery in 1837 of large neurons with many branching dendrites found in the cerebellum.
- He is also known for his 1839 discovery of fibrous tissue that conducts electrical impulsesfrom the atrioventricular node to all parts of the ventricles of the heart.
- Other discoveries include reflections of objects off the structure of the eye and changes in the brightness of red and blue colors as light intensity gradually decreases at dusk.
- He described the effects of camphor, opium, belladonna and turpentine on humans in 1829.
- He also experimented with nutmeg: he washed down three ground nutmegs with a glass of wine and experienced headaches, nausea, euphoria and hallucinations that lasted several days. Today, this phenomenon is called the average nutmeg binge.
- Jan Purkinje also discovered the sweat glands in 1833 and published a thesis that recognized 9 major groups of fingerprint configurations in 1823.
- He was also the first to describe and illustrate intracytoplasmic neuromelanin in the substantia nigra in 1838.
- Jan Purkinje also recognized the importance of Edward Muybridge's work and built his own version of the stroboscope, which he called phorolite. He placed nine photographs of himself on the disc, taken from different angles, and entertained his grandchildren by showing them how he, the old and famous professor, turns at great speed.
Private life and memory after death
In 1827, Purkiné married Julie Rudolphi, daughter of a professor of physiology from Berlin. They had four children, two of whom were girls who died in early childhood. After 7 years of marriage, Julie died, leaving Purkin with two young sons in deep despair.
The scientist died on July 28, 1869 in Prague. He wasburied in the cemetery for honorable citizens near the Czech Royal Castle in Vysehrad. Czechoslovakia issued two stamps in 1937 to commemorate the 150th anniversary of the birth of Purkyne (spelled Purkyne in Czech).
Masaryk University in Brno, Czech Republic, bore his name from 1960 to 1990, as did the autonomous Military Medical Academy in Hradec Králové (1994-2004).) Today, the university in Ust nad Labem bears his name.
The biography of Jan Purkinje shows us very clearly that a person, despite all the obstacles placed on him, can achieve very great heights in all areas of activity.
