Instruct: Given a question, retrieve passages that answer the question.
Query: When was penicillin discovered?
Penicillin (PCN or pen) is a group of antibiotics which include penicillin G (intravenous use), penicillin V (use by mouth), procaine penicillin, and benzathine penicillin (intramuscular use). Penicillin antibiotics were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are still widely used today, though many types of bacteria have developed resistance following extensive use.
About 10% of people report that they are allergic to penicillin; however, up to 90% of this group may not actually be allergic. Serious allergies only occur in about 0.03%. All penicillins are β-lactam antibiotics.
Penicillin was discovered in 1928 by Scottish scientist Alexander Fleming. People began using it to treat infections in 1942. There are several enhanced penicillin families which are effective against additional bacteria; these include the antistaphylococcal penicillins, aminopenicillins and the antipseudomonal penicillins. They are derived from "Penicillium" fungi.
The second half of the 20th century was the golden age of virus discovery and most of the over 2,000 recognised species of animal, plant, and bacterial viruses were discovered during these years. In 1957, equine arterivirus and the cause of Bovine virus diarrhoea (a pestivirus) were discovered. In 1963, the hepatitis B virus was discovered by Baruch Blumberg, and in 1965, Howard Temin described the first retrovirus. Reverse transcriptase, the enzyme that retroviruses use to make DNA copies of their RNA, was first described in 1970, independently by Howard Martin Temin and David Baltimore. In 1983 Luc Montagnier's team at the Pasteur Institute in France, first isolated the retrovirus now called HIV. In 1989 Michael Houghton's team at Chiron Corporation discovered Hepatitis C.
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Graphene was discovered at the University of Manchester in 2004 under Prof Sir Andre Geim and Sir Konstantin Novoselov.
At the Calico Printers' Association in Manchester in 1941, John Rex Whinfield and James Tennant Dickson discovered polyethylene terephthalate, known as PET, a common polyester compound found in plastic bottles and food, and also known as Terylene or Dacron. Cheslene and Crepes of Macclesfield discovered crimplene (the fabric that is now referred to as polyester). ICI Dyestuffs at Hexagon House, in Blackley in north Manchester, discovered Procion dyes. At the Winnington Laboratory on 27 March 1933, Eric Fawcett and Reginald Gibson discovered polythene in an ICI laboratory in Northwich, when reacting benzaldehyde with ethene at a pressure of 2,000 atmospheres; the process was improved in 1935 by Sir Michael Perrin.
In 1880, while working in the military hospital in Constantine, Charles Louis Alphonse Laveran discovered that the cause of malaria is a protozoan. He observed the parasites in a blood smear taken from a soldier who had just died of malaria. For this, he received the 1907 Nobel Prize for Physiology or Medicine. This was the first time that protozoa were shown to be a cause of disease. His work helped inspire researchers and veterinarians today to try to find a cure for malaria in animals.
Various genetic discoveries have been essential in the development of genetic engineering. Genetic inheritance was first discovered by Gregor Mendel in 1865 following experiments crossing peas. Although largely ignored for 34 years he provided the first evidence of hereditary segregation and independent assortment. In 1889 Hugo de Vries came up with the name "(pan)gene" after postulating that particles are responsible for inheritance of characteristics and the term "genetics" was coined by William Bateson in 1905. In 1928 Frederick Griffith proved the existence of a "transforming principle" involved in inheritance, which Avery, MacLeod and McCarty later (1944) identified as DNA. Edward Lawrie Tatum and George Wells Beadle developed the central dogma that genes code for proteins in 1941. The double helix structure of DNA was identified by James Watson and Francis Crick in 1953.As well as discovering how DNA works, tools had to be developed that allowed it to be manipulated. In 1970 Hamilton Smith's lab discovered restriction enzymes that allowed DNA to be cut at specific places and separated out on an electrophoresis gel. This enabled scientists to isolate genes from an organism's genome. DNA ligases, that join broken DNA together, had been discovered earlier in 1967 and by combining the two enzymes it was possible to "cut and paste" DNA sequences to create recombinant DNA. Plasmids, discovered in 1952, became important tools for transferring information between cells and replicating DNA sequences. Frederick Sanger developed a method for sequencing DNA in 1977, greatly increasing the genetic information available to researchers. Polymerase chain reaction (PCR), developed by Kary Mullis in 1983, allowed small sections of DNA to be amplified and aided identification and isolation of genetic material.
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Type 1 and type 2 diabetes were identified as separate conditions for the first time by the Indian physicians Sushruta and Charaka in 400–500 AD with type 1 associated with youth and type 2 with being overweight. The term "mellitus" or "from honey" was added by the Briton John Rolle in the late 1700s to separate the condition from diabetes insipidus which is also associated with frequent urination. Effective treatment was not developed until the early part of the 20th century when the Canadians Frederick Banting and Charles Best discovered insulin in 1921 and 1922. This was followed by the development of the long acting NPH insulin in the 1940s.
On December 29, 2011, chemists at Harvard University reported the creation of an artificial cell membrane.
Anselme Payen discovered in 1833 the first enzyme who called diastase and in 1878 German physiologist Wilhelm Kühne (1837–1900) coined the term "enzyme", which comes from Greek "ενζυμον" "in leaven", to describe this process. The word "enzyme" was used later to refer to nonliving substances such as pepsin, and the word "ferment" used to refer to chemical activity produced by living organisms.
Despite the lack of interest of his fellow scientists, he did conduct several experiments on the antibiotic substance he discovered. The most important result proved it was nontoxic in humans by first performing toxicity tests in animals and then on humans. His subsequent experiments on penicillin's response to heat and pH allowed Fleming to increase the stability of the compound. The one test that modern scientists would find missing from his work was the test of penicillin on an infected animal, the results of which would likely have sparked great interest in penicillin and sped its development by almost a decade.
The importance of his work has been recognized by the placement of an International Historic Chemical Landmark at the Alexander Fleming Laboratory Museum in London on November 19, 1999.
Swiss electrical engineer George de Mestral invented his first touch fastener when, in 1941, he went for a walk in the woods and wondered why Burdock seeds clung to his coat and dog. He discovered it could be turned into something useful. He patented it in 1955 and subsequently refined and developed its practical manufacture until its commercial introduction in the late 1950s.
Type 1 and type 2 diabetes were identified as separate conditions for the first time by the Indian physicians Sushruta and Charaka in 400–500 CE with type 1 associated with youth and type 2 with being overweight. The term "mellitus" or "from honey" was added by the Briton John Rolle in the late 1700s to separate the condition from diabetes insipidus, which is also associated with frequent urination. Effective treatment was not developed until the early part of the 20th century, when Canadians Frederick Banting and Charles Herbert Best isolated and purified insulin in 1921 and 1922. This was followed by the development of the long-acting insulin NPH in the 1940s.
The discovery of a role for the pancreas in diabetes is generally ascribed to Joseph von Mering and Oskar Minkowski, who in 1889 found that dogs whose pancreas was removed developed all the signs and symptoms of diabetes and died shortly afterwards. In 1910, Sir Edward Albert Sharpey-Schafer suggested that people with diabetes were deficient in a single chemical that was normally produced by the pancreas—he proposed calling this substance insulin, from the Latin "insula", meaning island, in reference to the insulin-producing islets of Langerhans in the pancreas. The endocrine role of the pancreas in metabolism, and indeed the existence of insulin, was further clarified in 1921, when Sir Frederick Grant Banting and Charles Herbert Best repeated the work of Von Mering and Minkowski, and went further to demonstrate they could reverse induced diabetes in dogs by giving them an extract from the pancreatic islets of Langerhans of healthy dogs. The islets of Langerhans was discovered in 1869 by an anatomist named Paul Langerhans. He identified the keys cells in the pancreas which produce the main substance that controls glucose levels in the body.
In August 1961, at the International Congress of Biochemistry in Moscow, Nirenberg presented his paper. The experimentation with synthetic RNA in a cell-free system was a key technical innovation. In 1961, when they announced their methods for decoding the relationship of mRNA to amino acids, there was still a lot of experimentation required before the entire code was deciphered. The scientists had to determine which bases made up each codon, then determine the sequence of bases in the codons. This proved to be a tremendous amount of work.
A French Army physician Charles Louis Alphonse Laveran discovered that malaria was caused by microscopic parasite (now called "Plasmodium falciparum") in 1880. But scientists were sceptical until Golgi intervened. It was Golgi who helped him prove that malarial parasite was a microscopic protozoan. From 1885, Golgi studied the malarial parasite and its transmission. He established two types of malaria, tertian and quartan fevers caused by "Plasmodium vivax" and "Plasmodium malariae" respectively. In 1886, he discovered that malarial fever (paroxysm) was produced by the asexual stage in the human blood (called erythocytic cycle, or Golgi cycle). In 1889-1890, Golgi and Ettore Marchiafava described the differences between benign tertian malaria and malignant tertian malaria (the latter caused by "P. falciparum"). By 1898, along with Giovanni Battista Grassi, Amico Bignami, Giuseppe Bastianelli, Angelo Celli and Marchiafava, he confirmed that malaria was transmitted by "Anopheline" mosquito.
In 1961, Jacques Monod, Jean-Pierre Changeux and François Jacob discovered the lac operon in the bacterium "Escherichia coli". It was a cluster of genes, arranged in a feedback control loop so that its products would only be made when "switched on" by an environmental stimulus. One of these products was an enzyme that splits a sugar, lactose; and lactose itself was the stimulus that switched the genes on. This was a revelation, as it showed for the first time that genes, even in an organism as small as a bacterium, were subject to fine-grained control. The implication was that many other genes were also elaborately regulated.
Another group working contemporaneously with the Montagnier and Gallo groups was that of Dr. Jay Levy at the University of California, San Francisco. He independently discovered the AIDS virus in 1983 and named it the AIDS associated retrovirus (ARV). This virus was very different from the virus reported by the Montagnier and Gallo groups. The ARV strains indicated, for the first time, the heterogeneity of HIV isolates and several of these remain classic examples of the AIDS virus found in the United States.
The 2008 Nobel Prize in Physiology or Medicine was awarded to Montagnier and Françoise Barré-Sinoussi for the discovery of HIV. They shared the Prize with Harald zur Hausen, who discovered that human papilloma viruses can cause cervical cancer. Montagnier said he was "surprised" that Robert Gallo was not also recognized by the Nobel Committee: "It was important to prove that HIV was the cause of AIDS, and Gallo had a very important role in that. I'm very sorry for Robert Gallo." According to Maria Masucci, a member of the Nobel Assembly, "there was no doubt as to who made the fundamental discoveries."
This science comprises three main sub-disciplines:The first modern example of polymer science is Henri Braconnot's work in the 1830s. Henri, along with Christian Schönbein and others, developed derivatives of the natural polymer cellulose, producing new, semi-synthetic materials, such as celluloid and cellulose acetate. The term "polymer" was coined in 1833 by Jöns Jakob Berzelius, though Berzelius did little that would be considered polymer science in the modern sense. In the 1840s, Friedrich Ludersdorf and Nathaniel Hayward independently discovered that adding sulfur to raw natural rubber (polyisoprene) helped prevent the material from becoming sticky. In 1844 Charles Goodyear received a U.S. patent for vulcanizing natural rubber with sulfur and heat. Thomas Hancock had received a patent for the same process in the UK the year before. This process strengthened natural rubber and prevented it from melting with heat without losing flexibility. This made practical products such as waterproofed articles possible. It also facilitated practical manufacture of such rubberized materials. Vulcanized rubber represents the first commercially successful product of polymer research. In 1884 Hilaire de Chardonnet started the first artificial fiber plant based on regenerated cellulose, or viscose rayon, as a substitute for silk, but it was very flammable. In 1907 Leo Baekeland invented the first synthetic plastic, a thermosetting phenol–formaldehyde resin called Bakelite.
Albert Ludwig Sigesmund Neisser (22 January 1855, Schweidnitz – 30 July 1916, Breslau) was a German physician who discovered the causative agent (pathogen) of gonorrhea, a strain of bacteria that was named in his honour ("Neisseria gonorrhoeae").
Hobby is recognized for her work in creating a form of penicillin that was effective on human hosts. In 1940, Hobby and her colleagues, Dr. Karl Meyer and Dr. Martin Henry Dawson, wrote to Howard Florey and Ernst Chain to procure a sample of penicillin. They naively decided to make some penicillin and soon became experts in the fermentation process, and began refining it into a drug. Hobby, Meyer, and Dawson performed the first tests of penicillin on humans in 1940 and 1941, before presenting at the American Society for Clinical Investigation. They discovered that penicillin was a powerful germ-killer that reduced the severity of infectious diseases and made procedures such as organ transplantation and open-heart surgery possible. Their findings received media coverage, which helped attract funding from the United States Government to mass-produce penicillin during World War II, saving the lives of many soldiers.
In 1959, Brockham Park became famous when Beecham scientists there discovered the penicillin nucleus, 6-APA (6-aminopenicillanic acid); This discovery allowed Beecham, working in tandem with Bristol-Myers, to synthesize of a number of new semisynthetic penicillins. Beecham marketed Broxil (phenethicillin), followed shortly by the more potent Celbenin (methicillin), which was active against "Staphylococcus aureus". The group continued to focus on pharmaceutical development, producing further semi-synthetic penicillins. However, when Penbritin (ampicillin) came on the market in 1961, Beecham's facilities were soon inadequate for the worldwide demand the drug generated. A complex at Worthing came on line in the early 1960s to produce phenethicillin, followed by the ability to produce 6-APA, the base for semisynthetic penicillins.
Fleming also discovered very early that bacteria developed antibiotic resistance whenever too little penicillin was used or when it was used for too short a period. Almroth Wright had predicted antibiotic resistance even before it was noticed during experiments. Fleming cautioned about the use of penicillin in his many speeches around the world. On 26 June 1945, he made the following cautionary statements: "the microbes are educated to resist penicillin and a host of penicillin-fast organisms is bred out ... In such cases the thoughtless person playing with penicillin is morally responsible for the death of the man who finally succumbs to infection with the penicillin-resistant organism. I hope this evil can be averted." He cautioned not to use penicillin unless there was a properly diagnosed reason for it to be used, and that if it were used, never to use too little, or for too short a period, since these are the circumstances under which bacterial resistance to antibiotics develops.
Ernst Chain, Howard Florey and Edward Abraham succeeded in purifying the first penicillin, penicillin G, in 1942, but it did not become widely available outside the Allied military before 1945. Later, Norman Heatley developed the back extraction technique for efficiently purifying penicillin in bulk. The chemical structure of penicillin was first proposed by Abraham in 1942 and then later confirmed by Dorothy Crowfoot Hodgkin in 1945. Purified penicillin displayed potent antibacterial activity against a wide range of bacteria and had low toxicity in humans. Furthermore, its activity was not inhibited by biological constituents such as pus, unlike the synthetic sulfonamides. (see below) The development of penicillin led to renewed interest in the search for antibiotic compounds with similar efficacy and safety. For their successful development of penicillin, which Fleming had accidentally discovered but could not develop himself, as a therapeutic drug, Chain and Florey shared the 1945 Nobel Prize in Medicine with Fleming.