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Imipenem
Imipenem (trade name Primaxin among others) is an intravenous β-lactam antibiotic discovered by Merck scientists Burton Christensen, William Leanza, and Kenneth Wildonger in the mid-1970s. Carbapenems are highly resistant to the β-lactamase enzymes produced by many multiple drug-resistant Gram-negative bacteria, thus play a key role in the treatment of infections not readily treated with other antibiotics. Imipenem was patented in 1975 and approved for medical use in 1985. It was discovered via a lengthy trial-and-error search for a more stable version of the natural product thienamycin, which is produced by the bacterium '' Streptomyces cattleya''. Thienamycin has antibacterial activity, but is unstable in aqueous solution, so impractical to administer to patients. Imipenem has a broad spectrum of activity against aerobic and anaerobic, Gram-positive and Gram-negative bacteria. It is particularly important for its activity against ''Pseudomonas aeruginosa'' and the ''Enterococc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbapenem Antibiotics
Carbapenems are a class of very effective antibiotic agents most commonly used for the treatment of severe bacterial infections. This class of antibiotics is usually reserved for known or suspected multiple drug resistance, multidrug-resistant (MDR) bacterial infections. Similar to penicillins and cephalosporins, carbapenems are members of the beta lactam class of antibiotics, which kill bacteria by binding to penicillin-binding proteins, thus inhibiting bacterial cell wall synthesis. However, these agents individually exhibit a broader spectrum of activity compared to most cephalosporins and penicillins. Furthermore, carbapenems are typically unaffected by emerging antimicrobial resistance, antibiotic resistance, even to other beta-lactams. Carbapenem antibiotics were originally developed at Merck & Co. from the carbapenem thienamycin, a naturally derived product of ''Streptomyces cattleya''. Concern has arisen in recent years over increasing rates of resistance to carbapenems, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antiseptics) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thienamycin
Thienamycin (also known as thienpenem) is one of the most potent naturally produced antibiotics known thus far, discovered in '' Streptomyces cattleya'' in 1976. Thienamycin has excellent activity against both Gram-positive and Gram-negative bacteria and is resistant to bacterial β-lactamase enzymes. Thienamycin is a zwitterion at pH 7. History In 1976, fermentation broths obtained from the soil bacterium '' Streptomyces cattleya'' were found to be active in a screen for inhibitors of peptidoglycan biosynthesis. Initial attempts to isolate the active compound proved difficult due to its chemical instability. After many attempts and extensive purification, the material was finally isolated in >90% purity, allowing for the structural elucidation of thienamycin in 1979 (Figure 1). Thienamycin was the first among the naturally occurring class of carbapenem antibiotics to be discovered and isolated. Carbapenems are similar in structure to their antibiotic “cousins” the penic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cilastatin
Cilastatin inhibits the human enzyme dehydropeptidase. Uses Dehydropeptidase is an enzyme found in the kidney and is responsible for degrading the antibiotic imipenem. Cilastatin can therefore be combined intravenously with imipenem in order to protect it from degradation, prolonging its antibacterial effect. Imipenem alone is an effective antibiotic and can be given without cilastatin. Cilastatin itself does not have antibiotic activity, although it has been proved to be active against a zinc-dependent beta-lactamase that usually confers antibiotic resistance to certain bacteria, more precisely, the carbapenem family of antibiotics. This property is due to the physicochemical similarities between membrane dipeptidase (MDP), the compound it is usually set to target, and the bacterial metallo-beta-lactamase carried by the CphA gene. The combination allows the antibiotic to be more effective by changing the pharmacokinetics involved. Thus imipenem/cilastatin, like amoxicillin/cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intramuscular Injection
Intramuscular injection, often abbreviated IM, is the injection of a substance into a muscle. In medicine, it is one of several methods for parenteral administration of medications. Intramuscular injection may be preferred because muscles have larger and more numerous blood vessels than subcutaneous tissue, leading to faster absorption than subcutaneous or intradermal injections. Medication administered via intramuscular injection is not subject to the first-pass metabolism effect which affects oral medications. Common sites for intramuscular injections include the deltoid muscle of the upper arm and the gluteal muscle of the buttock. In infants, the vastus lateralis muscle of the thigh is commonly used. The injection site must be cleaned before administering the injection, and the injection is then administered in a fast, darting motion to decrease the discomfort to the individual. The volume to be injected in the muscle is usually limited to 2–5 milliliters, depending on in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeromonas Hydrophila
''Aeromonas hydrophila'' is a heterotrophic, Gram-negative, rod-shaped bacterium mainly found in areas with a warm climate. This bacterium can be found in fresh or brackish water. It can survive in Wikt:aerobic, aerobic and Hypoxia (environmental), anaerobic environments, and can digest materials such as gelatin and hemoglobin. ''A. hydrophila'' was isolated from humans and animals in the 1950s. It is the best known of the species of ''Aeromonas''. It is resistant to most common antibiotics and cold temperatures and is oxidase- and indole-positive. ''Aeromonas hydrophila'' also has a symbiotic relationship as gut flora inside of certain leeches, such as ''Hirudo medicinalis''. Structure ''Aeromonas hydrophila'' bacteria are Gram-negative, straight rods with rounded ends (bacilli to coccibacilli shape) usually from 0.3 to 1.0 μm in width and 1.0 to 3.0 μm in length. They can grow at temperatures as low as 4 °C. These bacteria are motile by a polar flagellum. Path ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiopure Drugs
An enantiopure drug is a pharmaceutical that is available in one specific enantiomeric form. Most biological molecules (proteins, sugars, etc.) are present in only one of many chiral forms, so different enantiomers of a chiral drug molecule bind differently (or not at all) to target receptors. Chirality can be observed when the geometric properties of an object is not superimposable with its mirror image. Two forms of a molecule are formed (both mirror images) from a chiral carbon, these two forms are called enantiomers. One enantiomer of a drug may have a desired beneficial effect while the other may cause serious and undesired side effects, or sometimes even beneficial but entirely different effects. The desired enantiomer is known as an eutomer while the undesired enantiomer is known as the distomer. When equal amounts of both enantiomers are found in a mixture, the mixture is known as a racemic mixture. If a mixture for a drug does not have a 1:1 ratio of its enantiomers it is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillin
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum using deep tank fermentation and then purified. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: penicillin G (intramuscular or 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 still widely used today for different bacterial infections, though many types of bacteria have developed resistance following extensive use. 10% of the population claims penicillin allergies but because the frequency of positive skin test results decreases by 10% with each year of avoidance, 90% of these patients can tolerate penicillin. Additionally, those with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adverse Drug Reaction
An adverse drug reaction (ADR) is a harmful, unintended result caused by taking medication. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs. The meaning of this term differs from the term "side effect" because side effects can be beneficial as well as detrimental. The study of ADRs is the concern of the field known as ''pharmacovigilance''. An adverse drug event (ADE) refers to any unexpected and inappropriate occurrence at the time a drug is used, whether or not associated with the administration of the drug. An ADR is a special type of ADE in which a causative relationship can be shown. ADRs are only one type of medication-related harm, as harm can also be caused by omitting to take indicated medications. Classification ADRs may be classified by e.g. cause and severity. Cause *Type A: Augmented pharmacologic effects - dose dependent and predictable :Type A reactions, which constitute approximate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydropeptidase
Dipeptidases are enzymes secreted by enterocytes into the small intestine. Dipeptidases hydrolyze bound pairs of amino acids, called dipeptides. Dipeptidases are secreted onto the brush border of the villi in the small intestine, where they cleave dipeptides into their two component amino acids prior to absorption. They are also found within the enterocytes themselves, performing cytosolic digestion of absorbed dipeptides. Dipeptidases are exopeptidases, classified under EC number 3.4.13. See also * Membrane dipeptidase Membrane dipeptidase (, ''renal dipeptidase'', ''dehydropeptidase I (DPH I)'', ''dipeptidase'', ''aminodipeptidase'', ''dipeptide hydrolase'', ''dipeptidyl hydrolase'', ''nonspecific dipeptidase'', ''glycosyl-phosphatidylinositol-anchored renal di ... References External links * Enzymes EC 3.4.13 {{enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stenotrophomonas Maltophilia
''Stenotrophomonas maltophilia'' is an aerobic, nonfermentative, Gram-negative bacterium. It is an uncommon bacterium and human infection is difficult to treat. Initially classified as ''Bacterium bookeri'', then renamed ''Pseudomonas maltophilia'', ''S. maltophilia'' was also grouped in the genus ''Xanthomonas'' before eventually becoming the type species of the genus ''Stenotrophomonas'' in 1993. ''S. maltophilia'' is slightly smaller (0.7–1.8 × 0.4–0.7 μm) than other members of the genus. They are motile due to polar flagella, and grow well on MacConkey agar producing pigmented colonies. ''S. maltophilia'' is catalase-positive, oxidase-negative (which distinguishes it from most other members of the genus) and has a positive reaction for extracellular DNase. ''S. maltophilia'' is ubiquitous in aqueous environments, soil, and plants; it has also been used in biotechnology applications. In immunocompromised patients, ''S. maltophilia'' can lead to nosocomial inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterococcus Faecalis
''Enterococcus faecalis'' – formerly classified as part of the group D ''Streptococcus'' system – is a Gram-positive, commensal bacterium inhabiting the gastrointestinal tracts of humans. Like other species in the genus ''Enterococcus'', ''E. faecalis'' is found in healthy humans and can be used as a probiotic. The probiotic strains such as Symbioflor1 and EF-2001 are characterized by the lack of specific genes related to drug resistance and pathogenesis. As an opportunistic pathogen, ''E. faecalis'' can cause life-threatening infections, especially in the nosocomial (hospital) environment, where the naturally high levels of antibiotic resistance found in ''E. faecalis'' contribute to its pathogenicity. ''E. faecalis'' has been frequently found in reinfected, root canal-treated teeth in prevalence values ranging from 30% to 90% of the cases. Re-infected root canal-treated teeth are about nine times more likely to harbor ''E. faecalis'' than cases of primary infections. Physi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
