Penicillin (UK: Penicillin or PCN) is a group of β-lactam antibiotic used to treat infections caused by bacteria, usually Gram positif.Madigan, MT; Martinko JM, Dunlap PV, Clark DP. Brock Biology of Microorganisms (12th Edition ed.). San Francisco: Pearson Benjamin Cummings. p. p. 795. ISBN 9780321536150. Penicillin works by inhibiting bacterial cell wall formation, by inhibiting acid N-asetilmuramat Combined non-essential to the structure Mukopeptida usually makes cells become rigid and strong. This way of working also means that penicillin would only actively working on the unit pathogen actively growing. The name "penicillin" can also be used for a specific member of the penicillin group. All penicillins have Penam base, which has the formula R-C9H11N2O4S, where R is a variable side chain.
History.
The discovery of penicillin is always associated with a Scottish scientist, Alexander Fleming in 1929, even though many other scientists have noted before Fleming antibacterial effect.Fleming, in his laboratory at the Hospital of Santa Maria (now one of the teaching hospitals in London), noted a halo of inhibition (clear zone) on the growth of bacteria in the Staphylococcus plate culture. Fleming concluded that the resistance was due to a substance inhibiting bacterial growth and destroy. He grew a pure culture and discovered Penicillium which became known as Penicillium chrysogenum. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of Penicillium.
Although in the early stages, penicillin was found to be effective against Gram-positive bacteria and is ineffective in Gram negative and fungi. Fleming optimism that penicillin would be a very useful disinfectant, high potential with a low level of toxicity compared to antiseptics of the time.
In subsequent experiments, Fleming was convinced that penicillin could not last long in the human body to kill pathogenic bacteria. He stopped studying penicillin after 1931, but trying to start it again in 1934.
In 1939, Australian scientist Howard Walter Florey and a team of researchers at the University of Oxford made a significant progress in showing the in vivo bactericidal action of penicillin. They failed the test because not enough penicillin, but they proved harmless penicillin and work in mice. Several experiments carried out in Oxford penicillin. In 1942, John Bumstead and Orvan Hess became the first expert who successfully cure patients with penicillin.
During World War II, penicillin instrumental in suppressing the number of deaths from infections caused open wounds that did not receive treatment, which is in a similar situation can lead to gangrene and even death, saved the lives of 12-15%. The availability of penicillin is still very limited because of the difficulty to produce them en masse, and rapid renal clearance of residual penicillin frequent dosing. At that time, the collection returned penicillin from the patient's urine is a common procedure. Penicillin will be used again.
Reuse of penicillin is not the end of the road is good. This led researchers to look for another way to slow penicillin secretion. They hoped to find a molecule that could compete with penicillin for the organic acid transporter. The transporter function in the secretion of penicillin, it is predicted that the transporter will carry the penicillin molecule inhibitors that will last longer in the body. An agent probenecid finally proven to prevent. Probenecid will compete and inhibit the secretion of penicillin. Penicillin was finally able to work longer in the
body. Technique of mass production of penicillin was eventually able to overcome.
Chemical structure of penicillin by Dorothy Crowfoot Hodgkin known in the early 1940s. This makes the discovery of penicillin can be made synthetically. A team of Oxford discovered a method of mass production of penicillin. Tim Howard Walter Florey led it to get the Nobel Prize in Medicine or Physiology in 1945. At that time, the antibiotic penicillin became widely used and are still used for some Gram-positive bacterial infections.
The development of penicillin.
The first major development was ampicillin, which has a broader scope of activities than the original penicillin. The next development that can withstand produce penicillin beta-lactamase enzymes including flucloxacillin, dicloxacillin and methicillin. This discovery is very important to fight the bacteria species which have beta-lactamase, but not against strains of methicillin-resistant Staphylococcus aureus.
Penicillin is antipseudomal like Tisarsilin and Piperacillin useful against Gram-negative bacteria.
Mechanism of action.
Β-lactam antibiotics work by inhibiting the formation of peptidoglycan in the cell wall. Beta-lactam will be bound to the enzyme transpeptidase related to bacterial peptidoglycan molecules, and this will weaken the bacterial cell wall when splitting. In other words, these antibiotics can cause divisiveness cells (cytolysis) when the bacteria tries to divide.In Gram-positive bacteria cell wall would be lost protoplasts, whereas Gram-negative into sferoplas. Protoplasts and sferoplas then would rupture or lysis.
Clinical function.
The term "penicillin" is often used primarily to indicate benzylpenicillin.Benzathine benzylpenicillin.
Benzathine benzylpenicillin or benzathine penicillin, is slowly absorbed into the circulation, inserted or injected intramuscularly in the muscles, and hydrolysed to benzylpenicillin in vivo. The drug is selected when low concentrations of benzylpenicillin are required, allowing prolonged antibiotic action 2-4 weeks after a single IM dose.Specific indications for benzathine penicillin:
Prophylaxis of rheumatic feverEarly or latent syphilis
Benzylpenicillin (penicillin G).
Penicillin G (Benzylpenicillin)
Benzylpenicillin or penicillin G is the gold standard penicillin. Penicillin G is typically given by a parenteral because it is unstable with hydrochloric acid in the stomach. Penicillin G is the first effective antibiotic clinically, discovered by Howard Florey and his colleagues in 1939Specific indications for benzylpenicillin:
CelluliteBacterial endocarditis
Meningitis
Aspiration pneumonia, lung abscess
Syphilis
Septicemia in children
Phenoxymethylpenicillin (penicillin V) [edit | edit source]
Phenoxymethylpenicillin, or known as penicillin V, is the orally active penicillin (administered orally). The drug is less active than benzylpenicillin. This medicine is only appropriate in conditions of high tissue concentrations are not required.
Specific indications for phenoxymethylpenicillin;
Infections due to Streptococcus pyogenesTonsillitis
Pharyngitis
Dermatitis
Prophylaxis of rheumatic fever
Moderate-to-severe gingivitis (with metronidazole)
Procaine benzylpenicillin.
Procaine benzylpenicillin or procaine penicillin, is a combination of benzylpenicillin with the local anesthetic agent procaine. Intramuscular injection, it is slowly absorbed into the circulation and hydrolysed to benzylpenicillin.
This combination aims to reduce the pain and discomfort associated with injections of penicillin that much into muscle. This treatment is often used in veterinary medicine.
Specific indications for procaine penicillin;
SyphilisRespiratory tract infections
Cellulitis
The drug is also used in anthrax.
emi-synthetic penicillin.
Structural modifications on the side chain of the penicillin nucleus to enhance the ability of the drug, stabilizing beta-lactamase activity, and increase the scope of work.
Penicillin narrow scope.
This group was developed to be effective against beta-lactamase produced by Staphylococcus aureus, and is known as an anti-staphylococcal penicillin.Penicillin scope being.
This group was developed to increase the scope of work, such as amoxicillin.
AmoxicillinAmpicillin
Penicillin is a broad scope.
This group was developed to increase efficacy against Gram-negative bacteria.
PiperacillinTisarsilin
Azlosillin
Carbenicillin
Penicillin with β-lactamase inhibitors.
Penicillin can be combined with beta-lactamase inhibitors to help fight the enzyme beta-lactamase.
Side effects.
Adverse reactions.
Frequent adverse reactions are (≥ 1% of patients) diarrhea, urticaria, nausea, and superinfection dri Candidiasis. Effects rare (0.1-1% of patients) include fever, vomiting, dermatitis, angioedema or pseudomembarnosus colitis.Allergy.
Allergy to beta-lactam antibiotic may occur in 10% of patients. 0:01% may suffer from anaphylaxis.Thank you for reading this article. Written and posted by Bambang Sunarno. sunarnobambang86@gmail.com
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DatePublished: February 26, 2014 at 20:49
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