Tác dụng của Penicillin

When discussing the antibiotic breakthrough of penicillin, the name which is most often associated with its discovery tends to be Alexander Fleming. While this is not completely false, there are many other factors as well as persons which aided in uncovering penicillin’s full potential in human uses.
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Tác dụng của Penicillin Penicillin The Wonder DrugWhen discussing the antibiotic breakthrough of penicillin, the name which is most oftenassociated with its discovery tends to be Alexander Fleming. While this is not completely false,there are many other factors as well as persons which aided in uncovering penicillin’s fullpotential in human uses.Penicillin was not created overnight. In fact, over a decade had passed from the time thatAlexander Fleming first noticed the seemingly odd culture of gram-positive bacteria in 1928 tothe first human test in 1941. As there are many different accounts and versions of the penicillinstory, some of the details may differ. However, one piece of information which stays constant isthat Alexander Fleming was not alone in creating the wonder drug, penicillin.I have found the following sites to be very thorough in describing the discovery, production, anduses of penicillin. I have included a summary of the general information regarding penicillin, fora more in depth description please visit these other sites.Tom Volk - Mycology - University of Wisconsin, La CrosseGeorge Wong - Botany - HawaiiThe Discovery:The story which most people are familiar with entails Alexander Fleming accidentlyleaving a culture dish of Staphylococcus aureus bacteria uncovered for a number ofdays. When returning to the bacteria, Fleming noticed mold had begun to grow as well.He incorrectly names named the fungus Penicillium rubra. (Later it was re-named byCharles Thom as Penicillium notatum which was found to be the same species asPenicillium chrysogenum). What made this fungus growth interesting was that thebacteria ceased to exist in the area near it. Below is a quote from Alexander Flemingwhich was referenced in Judith Kaye’s book, The Life of Alexander Fleming.On this particular occasion, the mould which developed appeared to be dissolving the bacteria.That was very unusual, so instead of casting out the contaminated culture with appropriatelanguage, I made some investigations and the more I investigated it the more interesting itbecame” (Fleming).Now, you may be wondering what a fungus prohibiting the growth of bacteria has to do withsaving people’s lives. It may surprise you to learn that most deaths prior to the use of penicillinwere due to bacterial infections, not bleeding to death or other occurrences. Fleming recognizedthat inhibiting the growth of bacteria could potentially be used to lessen the number of bacterialrelated deaths.This is where one must decide if Fleming should be credited for the discovery of penicillin. Isthis initial, chance production of a mold which prohibits the growth of some bacteria enough togive Fleming credit for the miracle drug penicillin? Most people agree that Fleming should becredited merely for realizing that something odd did in fact occur. Had Fleming thrown theculture out and not recognized the importance of it, the production of penicillin would have beengreatly delayed. However, it was later scientists which revealed the human uses of the mold inthe form of antibiotics.Over ten years later, in 1939, Oxford University scientists (ErnstChain and Howard Florey) were able to reproduce the moldwhich was seen on Fleming’s contaminated culture and use it inmice to treat infections. In 1941 the first human trial tookplace. The man who was being treated died due to a lack ofpenicillin.The arrival of World War II sparked interest in the new antibiotic, and there was search to find asource which could provide a sufficient amount of penicillin. Interestingly, there was a womanhired for the sole purpose of finding different molds with hopes of finding a high penicillinconcentration. Some accounts say that the final source was moldy liquor; others say it was due toa melon which was brought to the scientists.Whatever the source, this new abundance of penicillin combined with Louis Pasteur’s GermTheory of Disease (infectious diseases are caused by germs) greatly decreased the number ofdeaths due to bacterial infections in WWII and continues to be used today.In 1945 Alexander Fleming, Ernst Chain, and Howard Florey received the Nobel Prize inphysiology/medicine for their work with the fungus Penicillium chrysogenum and thebenefits yielded to mankind.How Does It Work?Penicillin works on gram-positive bacteria. Thesebacteria contain a cell wall made of peptidoglycan,and it is this cell wall which penicillin reacts with toweaken the bacteria and ultimately destroy it.The Future of Penicillin:As you are probably aware, the effects of penicillin are not as great as they once were. This isdue to a number of factors which are all summed up in penicillin resistance. In other words, thebacteria are becoming immune to the effects of penicillin. This is brought on by many thingswhich all are linked back to good ol’ Charles Darwin and his theory on selection of the fit ...