Louis Pasteur

One of the few streets in Saigon,Vietnam that has not been renamed since colonial times is named in honour of Pasteur. It was for this observation that he was elected a Fellow of the Royal Society in 1789. A biographical film of his life has also been made, entitled The Story of Louis Pasteur. Jenner was a keen observer of nature and he was one of the first to write about the baby cuckoo's action of pushing the eggs and the young of its host out of the nest so that the baby cuckoo was the only one to receive food from its foster parents. In popular culture, Pasteur is the eponymous French scientist, his name appearing in science fiction shows like Star Trek. The spot where the balloon descended is today the location of the "Air Balloon" public house. Accordingly, he has been hailed as the "Father of Medicine" and a "Benefactor of Humanity." Craters on Mars and the Moon are named in his honor. Together with the owner of Berkeley Castle, he made a successful flight to nearby Stroud.

In fact, Pasteur inaugurated the modern age of medicine, leading to an increase in the human life span and a surprising population explosion. One of Jenner's interests was hot air ballooning. Pasteurization led to the elimination of contaminated milk and other drinks as sources of disease. Jenner's house in Berkeley, also known as The Chantry, is now the Jenner Museum. Pasteur's method of immunization was effective and was employed by many other physicians, eventually leading to the eradication of the diseases typhus and polio as threats. He studied anatomy and surgery under the guidance of John Hunter, a prominent surgeon in London, then returned to Berkeley to start a practice. He was buried in the Cathedral of Notre Dame, but his remains were soon placed in a crypt in the Institut Pasteur, Paris. For this pioneering work in vaccination Jenner is regarded as the Father of Immunization.

He died in 1895 near Paris from complications caused by a series of strokes that had begun plaguing him as far back as 1868. Jenner realised the long-term implications of vaccination, and looked forward to the day when smallpox would no longer be a threat anywhere on earth; his dream eventually reached fruition with the global eradication of smallpox in the late 1970s. Pasteur won the Leeuwenhoek medal, microbiology's highest honour, in 1895. The term virus was introduced in the work aforementioned. The first of the Pasteur Institutes was also built on the basis of this achievement. His work was published as "An Inquiry into the Causes and Effects of the Variolae Vaccinae, a Disease Known by the Name of Cow Pox" in 1798. The treatment's success laid the foundations for the manufacture of many other vaccines. Jenner called his method vaccination, as the original infective material came from a cow (vacca is the Latin for cow).

Fortunately, the treatment proved to be a spectacular success, with Meister avoiding the disease; thus, Pasteur was hailed as a hero and the legal matter was not pursued. Jenner then applied the standard smallpox inoculation; the boy was completely unaffected, showing that cowpox had made him immune to smallpox. This was done at some personal risk for Pasteur, since he was not a licensed physician and could have faced prosecution for treating the boy. The boy contracted cowpox, and after six weeks, recovered safely. This vaccine was first used on 9-year old Joseph Meister on July 6, 1885 after the boy was badly mauled by a rabid dog. On May 14, 1796, he tested cowpox, infecting an eight year old boy named James Phipps in the same manner as used in smallpox inoculation, but using material from a cowpox pustule. The vaccine had only been tested in 11 dogs before its first human trial. Cowpox is related to smallpox and Jenner realized that if the folk tradition were true it offered considerable advantages over the use of smallpox in inoculation.

The rabies vaccine was initially created by Emile Roux, a French doctor and a collegue of Pasteur who had been working with a killed vaccine produced by desiccating the spinal cords of infected rabbits. (It has been theorized that the romantic image of the beautiful milkmaid came from the fact that milkmaids often contracted cowpox, and would thereafter be immune to the disfigurement of smallpox.). Pasteur produced the first vaccine for rabies by growing the virus in rabbits and then weakening it by drying the affected nerve tissue. There was a local folk tradition amongst those who milked cows, that an infection with the so-called 'cowpox' protected one from contracting smallpox. This discovery revolutionised work in infectious diseases, and Pasteur gave these artificially weakened diseases the generic name of vaccines, to honour Jenner's discovery. This made them a risk to any family or acquaintances not already immune. The difference with chicken cholera and anthrax was that the weakened form of the disease organism had been generated artificially, and so a naturally weak form of the disease organism did not need to be found. However, it had two major disadvantages: it was dangerous, and until the infection from inoculation had run its course, the subject was infected, and infectious, with actual smallpox.

Edward Jenner had also discovered vaccination, using cowpox to give cross-immunity to smallpox, and by Pasteur's time this had generally replaced the use of actual smallpox material in inoculation. In Jenner's time, the practice of smallpox inoculation was commonplace in England. Inoculation with smallpox was known to result in far less scarring and greatly reduced mortality than with the naturally acquired disease. Jenner's early education included a spell at Cirencester Grammar School, where one of the school 'houses' was named after him in later years to commemorate his achievements. The notion of a weak form of a disease causing immunity to the virulent version was not new: this had been known for a long time for smallpox. Edward Jenner (May 17, 1749 - January 26, 1823) was an English country doctor practicing in Berkeley, Gloucestershire, England, famous for his work introducing the Smallpox vaccine. Pasteur's oxygen method did eventually produce a vaccine but only after he had been awarded a patent on the production of an anthrax vaccine. Vaccination.

This method used the oxidizing agent potassium dichromate. Vaccine. His laboratory notebooks now in the Bibliotheque Nationale in Paris in fact show that Pasteur used the method of a rival Jean-Joseph-Henri Toussaint, a Toulouse veterinary surgeon to create the anthrax vaccine. Pasteur publicaly claimed that he had made the anthrax vaccine by exposign the bacilus to oxygen. In the 1870s he applied this immunization method to anthrax, which affected cattle, and aroused interest in combating other diseases.

Pasteur guessed that the recovered animals now might be immune to the disease as were the animals at Eure-et-Loir that had recovered from anthrax. Chamberland assumed that an error had been made, and wanted to discard the apparently faulty culture out when Pasteur stopped him. On his return the month old cultures made the chickens unwell but instead of the infection being fatal as usual the chickens recovered completely. Chamberland failed to do this but instead went on holiday himself.

His assistant Charles Chamberland had been instructed to innocuate the chickens after Pasteur went on holiday. This discovery was an accident. Upon reusing these healthy chickens, Pasteur discovered that he could not infect them, even with fresh bacteria: the weakened bacteria had caused the chickens to become immune to the disease, although they had not actually caused the disease. During this work, a culture of the responsible bacteria had spoiled and failed to induce the disease in some chickens he was infecting with the disease.

His later work on diseases included work on chicken cholera. Pasteur also discovered anaerobiosis - that some microorganisms can develop and live without air or oxygen. Pasteur worked several years proving that it was a microbe attacking silkworm eggs which caused the disease, and that eliminating this microbe within silkworm nurseries would eradicate the disease. In 1865, a disease called pebrine was killing great numbers of silkworms.

He proposed preventing the entry of microorganisms into the human body, leading Joseph Lister to develop antiseptic methods in surgery. Beverage contamination led Pasteur to conclude that microorganisms infected animals and humans as well. This process was soon afterwards known as pasteurization. He and Claude Bernard completed the first test on April 20, 1862.

With this established, he invented a process in which liquids such as milk were heated to kill all bacteria and molds already present within them. Pasteur's research also showed that some microorganisms contaminated fermenting beverages. While Louis Pasteur did not develop germ theory (Girolamo Fracastoro, Friedrich Henle and others had suggested it earlier), he conducted experiments that clearly indicated its correctness and managed to convince most of Europe that it was true. Thus, Pasteur dealt the death blow to the theory of spontaneous generation and supported germ theory.

Nothing grew in the broths; therefore, the living organisms that grew in such broths came from outside, as spores on dust, rather than being spontaneously generated within the broth. He exposed boiled broths to air in vessels that contained a filter to prevent all particles from passing through to the growth medium and even in vessels with no filter at all, with air being admitted via a long tortuous tube that would not allow dust particles to pass. Louis Pasteur demonstrated that the fermentation process is caused by the growth of microorganisms, and that the growth of microorganisms in nutrient broths is not due to spontaneous generation. In 1857, he was made administrator and director of scientific studies of the École Normale Supérieure.

In 1854, he was named Dean of the new College of Science in Lille. His doctoral thesis on crystallography got him a position of professor of chemistry at the Faculté (College) of Strasbourg. As the first demonstration of chiral molecules, it was quite an achievement, but Pasteur then went on to his more famous work in the field of biology/medicine. Pasteur correctly deduced that the tartaric acid molecule was asymmetric and could exist in two different forms that resemble one another as a left- and right-hand glove resemble one another.

An equal mix of the two had no effect on polarized light. Tediously sorting the crystals by hand gave two forms of tartaric acid: solutions of one form rotated polarised light clockwise, while the other form rotated light counterclockwise. Pasteur noticed, upon examination of the tiny crystals of tartaric acid, that the crystals came in two asymmetric forms that were mirror images of one another. The mystery was that tartaric acid derived by chemical synthesis had no such effect, even though its reactions were identical and its elemental composition was the same.

A solution of this compound derived from living things (specifically, wine lees) rotated the plane of polarization of light passing through it. In his early work as a chemist he resolved a problem concerning the nature of tartaric acid (1849). .
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He also famously quoted: "Le hasard favorise l’esprit preparé" ("Chance favors the prepared mind"). He is known to the general public for his demonstration of the germ theory of disease and his development techniques of inoculation, most notably the first vaccine against rabies; however, he also made a major discovery in the field of chemistry, regarding asymmetric molecules and the polarization of light. Louis Pasteur (December 27, 1822 – September 28, 1895) was a French microbiologist and chemist.