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Aretaeus, Greek physician from Cappadocia who practiced in Rome and Alexandria, led a revival of Hippocrates’ teachings, and is thought to have ranked second only to the father of medicine himself in the application of keen observation and ethics to the art. In principle he adhered to the pneumatic school of medicine, which believed that health was maintained by “vital air,” or pneuma. Pneumatists felt that an imbalance of the four humours—blood, phlegm, choler (yellow bile), and melancholy (black bile)—disturbed the pneuma, a condition indicated by an abnormal pulse. In practice, however, Aretaeus was an eclectic physician, since he utilized the methods of several different schools.
After his death he was entirely forgotten until 1554, when two of his manuscripts, On the Causes and Indications of Acute and Chronic Diseases (4 vol.) and On the Treatment of Acute and Chronic Diseases (4 vol.), both written in the Ionic Greek dialect, were discovered. These works not only include model descriptions of pleurisy, diphtheria, tetanus, pneumonia, asthma, and epilepsy but also show that he was the first to distinguish between spinal and cerebral paralyses. (He gave diabetes its name (from the Greek word for “siphon,” indicative of the diabetic’s intense thirst and excessive emission of fluids) and rendered the earliest clear account of that disease now known.
Source: Encyclopaedia Britannica
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THE ORIGIN OF ISLETS OF LANGERHANS
Paul Langerhans was born in Berlin on 25 July 1847, the son of a successful Berlin physician,
Paul Langerhans senior (1820-1909) who was also a well known local government politician, becoming
president of the Berlin City Council. His mother (n6e Keibel) was a cousin of the distinguished embryologist
Franz Karl Julius Keibel (1861-1929). Two of Paul Langerhans' brothers were physicians - Robert (1859-1904) who was first assistant to Virchow and later occupied the Chair of Pathology and Richard, who practised in Berlin.
Langerhans began his medical studies in the University of Jena 1865/66, where one of his teachers
was the eminent morphologist, Ernst Haeckel (1834-1919), and he then transferred to the Friedrich Wilhelm
University, Berlin, where he was a student of Emil Du Bois-Reymond (1818-1896), Rudolf Virchow (1821-1902) and Julius Cohnheim (1839-1884). He
was chiefly influenced by the last two and became a close friend of Virchow.
Langerhans' first major histological discovery was in 1867, while still a medical student. Working in
Virchow's laboratory at the Berlin Pathological Institute, he investigated the innervation ofthe skin,
using the gold chloride staining technique developed by his teacher Cohnheim and he demonstrated the
non-pigmentary dendritic cells or stellate corpuscles which now bear his name and which he described in
his paper 'Ueber die Nerven der Menschlichen Haut' published in Virchow's Archiv (1868). Langerhans
had no idea of the function of these cells which are now known to be derived from the bone marrow and
to be macrophages which play a role in cell-mediated immunity.
In the same paper' Langerhans described the granular cells in the exterior portion of the Malpighian
layer of the epidermis, the stratum granulosum otherwise known as the layer of Langerhans. (These
cells described by Langerhans should not, of course, be confused with the Langhans cells which were
described by his contemporary, Theodor Langhans (1839-1915))
Langerhans' most famous histological discovery, the pancreatic islets, was also made while still a medical
student. During the summer of 1867 and then, after an interval of about a year, from the autumn of 1868 he
pursued his researches for his MD thesis 'Beitrage zur mikroskopischen Anatomie der Bauchspeicheldruse'
, which he defended publicly on 18 February 1869. In this medical classic, he described the microscopical
appearance in the rabbit's pancreas of the acinar glandular cells which secrete the pancreatic
digestive enzymes but scattered among them, in the inter-acinar spaces, were '. . . kleine Zellen von meist
ganz homogenem Inhalt und polygonaler mit rundern Kern ohne Kernkorpechen meist zu zweien oder
zu kleinen Gruppen beisammen liegende.' (English translation '. . . small cells of almost perfect homogeneous
content and of a polygonal form, with round nuclei without nucleoli, mostly lying together in pairs
or small groups.)
Langerhans admitted that he did not know the function of these special cells. It was not until 1893
that E Laguesse of Lille first postulated that these cells might produce an internal secretion and named
them 'les ilots de Langerhans.' He wrote:
'Langerhans est le premier, la 1869, a signale dans le
pancreas adulte de petits amas en groupes de cellules
speciales dissemines de place en place entre les acini, et a
signification inconnue ... Dans le pancreas d'un homme
adulte je retrouve ces ilots tr6s nombreux et volumineux (je
les designerai provisoirement sous le nom d'ilots de
Langerhans).'
Source: Journal of the Royal Society of Medicine
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THE BIRTH OF INSULIN
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The story of the discovery of insulin has been well chronicled beginning with a young physician, Frederick Banting, in London, Ontario, imagining that it might be possible to isolate the internal secretions of the pancreas by ligating the pancreatic ducts to induce atrophy of the acinar cells and thereby minimize contamination of the tissue extract with digestive enzymes. Banting presented his suggestion to J. J. R. Macleod, a distinguished physiologist at the University of Toronto who provided Banting with a laboratory for the summer and some dogs for the experiments. Macleod also assigned Charles Best, a young student, to work as Banting's assistant for the summer. During the summer of 1921, Banting and Best made remarkable progress, and by fall they had isolated material from pancreas extracts that dramatically prolonged the lives of dogs made diabetic by removal of the pancreas. In the winter of 1922, Banting and Best treated their first human patient, a young boy, who's life was saved by the treatment. This was a stunning accomplishment. Consider that from the start of the research in the summer of 1921 to treating a human patient successfully in the winter of 1922, the pace, especially by current standards for clinical treatments, was remarkable.
With that achievement, Macleod, who had been initially unenthusiastic about the work, assigned his entire laboratory to the insulin project. He also enlisted the Eli Lilly Company to aid in the large scale, commercial preparation of insulin although the University of Toronto received the patent for insulin production. By 1923, insulin was available in quantities adequate for relatively widespread treatment of diabetes. Although the success of the insulin project was remarkable, the rewards for the research workers were, it seems, quite controversial. The 1923 Noble Prize in Physiology or Medicine was awarded to Banting and Macleod. Apparently, Banting was annoyed at the omission of Best and gave him half of his share of the prize. There was also, perhaps, the feeling that Macleod had done little in the initial stages of the work and was an undeserving recipient. Macleod split his share of the Prize with J. B. Collip who had made contributions to the later stages of the work on insulin purification.
After the spectacular events of 1921–1923, the University of Toronto established the Banting and Best Department of Medical Research separate from the University. Banting accomplished little during the rest of his career and died in a plane crash in 1940. Best, however, had a long successful tenure at the University of Toronto working on insulin and subsequently other important topics including the importance of dietary choline and the development of heparin as an anticoagulant. |
