20th+

Saturday, February 13, 2016

A government-produced film (1964) about the discovery of penicillin by Sir Alexander Fleming, and the continuing development of its use as an antibiotic by Howard Florey and Ernst Boris Chain. The film uses many modernist animations to depict the scientific research. This video was made from material preserved by the BFI National Archive. Find out more: http://catalogue.wellcomelibrary.org/.... .

Sir Alexander Fleming discusses the problem of antibiotic resistance in 1945: https://soundcloud.com/wellcomelibrar.... .

The history of penicillin follows a number of observations and discoveries of apparent evidence of antibiotic activity of the mould Penicillium. Following the identification of Penicillium rubens as the source of the compound in 1928 and with the production of pure compound in 1942, penicillin became the first naturally derived antibiotic. There are anecdotes about ancient societies using moulds to treat infections, and in the following centuries many people observed the inhibition of bacterial growth by various moulds. However, it is unknown if the species involved were Penicillium species or if the antimicrobial substances produced were penicillin.

While working at St Mary's Hospital in London, Scottish physician Alexander Fleming was the first to experimentally discover that a Penicillium mould secretes an antibacterial substance, and the first to concentrate the active substance involved, which he named penicillin in 1928. The mould was determined to be a rare variant of Penicillium notatum (now Penicillium rubens), a laboratory contaminant in his lab. For the next 16 years, he studied on methods of better production of penicillin, medicinal uses and clinical trial. His successful treatment of Harry Lambert who had fatal streptococcal meningitis in 1942 proved to be a critical moment in the medical usage of penicillin.

Many later scientists were involved in the stabilization and mass production of penicillin and in the search for more productive strains of Penicillium. Important contributors include Ernst Chain, Howard Florey, Norman Heatley and Edward Abraham. Fleming, Florey and Chain shared the 1945 Nobel Prize in Physiology or Medicine for the discovery and development of penicillin. Dorothy Hodgkin received the 1964 Nobel Prize in Chemistry determining the structures of important biochemical substances including penicillin. Shortly after the discovery of penicillin, there were reports of penicillin resistance in many bacteria. Research that aims to circumvent and understand the mechanisms of antibiotic resistance continues today.

Penicillins (P, PCN or PEN) are a group of antibiotics originally obtained from Penicillium moulds, principally P. chrysogenum and P. rubens. Most penicillins in clinical use are chemically synthesised from naturally-produced penicillins. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: penicillin G (intravenous use) and penicillin V (given by mouth). Penicillins were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are members of the β-lactam antibiotics, which are some of the most powerful and successful achievements in modern science.[2] They are still widely used today for different bacterial infections, 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%. Those who are allergic to penicillin are most often given cephalosporin C (another β-lactam antibiotic) because there is only 10% crossover in allergy between the penicillins and cephalosporins.

Penicillin was discovered in 1928 by Scottish scientist Alexander Fleming as a crude extract of P. rubens. Fleming's student Cecil George Paine was the first to successfully use penicillin to treat eye infection (ophthalmia neonatorum) in 1930. The purified compound (penicillin F) was isolated in 1940 by a research team led by Howard Florey and Ernst Boris Chain at the University of Oxford. Fleming first used the purified penicillin to treat streptococcal meningitis in 1942. For the discovery, Fleming shared the 1945 Nobel Prize in Physiology or Medicine with Florey and Chain.

There are several semi-synthetic penicillins which are effective against a broader spectrum of bacteria: these include the antistaphylococcal penicillins, aminopenicillins and the antipseudomonal penicillins.

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Tuesday, February 16, 2016

Military Casualties

Saturday, February 13, 2016

Painfully Slow - Progress of Medicine, Surgery

Penicillin, Discovery 1928

PTSD Risk

Wednesday, February 10, 2016

Surgery, Medicine, Pharmacology - History

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