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Cyclo-oxygenase
Cyclooxygenase (COX), officially known as prostaglandin-endoperoxide synthase (PTGS), is an enzyme (specifically, a family of isozymes, ) that is responsible for formation of prostanoids, including thromboxane and prostaglandins such as prostacyclin, from arachidonic acid. A member of the animal-type heme peroxidase family, it is also known as prostaglandin G/H synthase. The specific reaction catalyzed is the conversion from arachidonic acid to prostaglandin H2 via a short-living prostaglandin G2 intermediate. Pharmaceutical inhibition of COX can provide relief from the symptoms of inflammation and pain. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, exert their effects through inhibition of COX. Those that are specific to the COX-2 isozyme are called COX-2 inhibitors. The active metabolite (AM404) of paracetamol is a COX inhibitor, a fact to which some or all of its therapeutic effect has been attributed. In medicine, the root symbol "CO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COX-2 Inhibitor
COX-2 inhibitors are a type of nonsteroidal anti-inflammatory drug (NSAID) that directly targets cyclooxygenase-2, COX-2, an enzyme responsible for inflammation and pain. Targeting selectivity for COX-2 reduces the risk of peptic ulceration and is the main feature of celecoxib, rofecoxib, and other members of this drug class. After several COX-2-inhibiting drugs were approved for marketing, data from clinical trials revealed that COX-2 inhibitors caused a significant increase in heart attacks and strokes, with some drugs in the class having worse risks than others. Rofecoxib (sold under the brand name Vioxx) was taken off the market in 2004 because of these concerns, while celecoxib (sold under the brand name Celebrex) and traditional NSAIDs received boxed warnings on their labels. Many COX-2-specific inhibitors have been removed from the US market. As of December 2011, only Celebrex (generic name of celecoxib) is still available for purchase in the United States. In the European ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonsteroidal Anti-inflammatory Drug
Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of use, but largely include an increased risk of gastrointestinal ulcers and bleeds, heart attack, and kidney disease. The term ''non-steroidal'', common from around 1960, distinguishes these drugs from corticosteroids, which during the 1950s had acquired a bad reputation due to overuse and side-effect problems after their initial introduction in 1948. NSAIDs work by inhibiting the activity of cyclooxygenase enzymes (the COX-1 and COX-2 isoenzymes). In cells, these enzymes are involved in the synthesis of key biological mediators, namely prostaglandins, which are involved in inflammation, and thromboxanes, which are involved in blood clotting. There are two general types of NSAIDs available: non-selective, and COX-2 selective. Most N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTGS2
Prostaglandin-endoperoxide synthase 2 (prostaglandin G/H synthase and cyclooxygenase) (The HUGO official symbol is PTGS2; HGNC ID, HGNC:9605), also known as cyclooxygenase-2 or COX-2, is an enzyme that in humans is encoded by the ''PTGS2'' gene. In humans it is one of two cyclooxygenases. It is involved in the conversion of arachidonic acid to prostaglandin H2, an important precursor of prostacyclin, which is expressed in inflammation. Function PTGS2 (COX-2), converts arachidonic acid (AA) to prostaglandin endoperoxide H2. PTGSs are targets for NSAIDs and PTGS2 (COX-2) specific inhibitors called coxibs. PTGS-2 is a sequence homodimer. Each monomer of the enzyme has a peroxidase and a PTGS (COX) active site. The PTGS (COX) enzymes catalyze the conversion of arachidonic acid to prostaglandins in two steps. First, hydrogen is abstracted from carbon 13 of arachidonic acid, and then two molecules of oxygen are added by the PTGS2 (COX-2), giving PGG2. Second, PGG2 is reduced to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analgesic
An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It is typically used to induce cooperation with a medical procedure. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in some instances eliminate, sensation, although analgesia and anesthesia are neurophysiologically overlapping and thus various drugs have both analgesic and anesthetic effects. Analgesic choice is also determined by the type of pain: For neuropathic pain, traditional analgesics are less effective, and there is often benefit from classes of drugs that are not normally considered analgesics, such as tricyclic antidepressants and anticonvulsants. Various analgesics, such as many NSAIDs, are available over the counter in most countries, whereas various others are prescription drugs owing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COX-2
Prostaglandin-endoperoxide synthase 2 (prostaglandin G/H synthase and cyclooxygenase) (The HUGO official symbol is PTGS2; HGNC ID, HGNC:9605), also known as cyclooxygenase-2 or COX-2, is an enzyme that in humans is encoded by the ''PTGS2'' gene. In humans it is one of two cyclooxygenases. It is involved in the conversion of arachidonic acid to prostaglandin H2, an important precursor of prostacyclin, which is expressed in inflammation. Function PTGS2 (COX-2), converts arachidonic acid (AA) to prostaglandin endoperoxide H2. PTGSs are targets for NSAIDs and PTGS2 (COX-2) specific inhibitors called coxibs. PTGS-2 is a sequence homodimer. Each monomer of the enzyme has a peroxidase and a PTGS (COX) active site. The PTGS (COX) enzymes catalyze the conversion of arachidonic acid to prostaglandins in two steps. First, hydrogen is abstracted from carbon 13 of arachidonic acid, and then two molecules of oxygen are added by the PTGS2 (COX-2), giving PGG2. Second, PGG2 is reduced to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inflammation. This includes painful menstrual periods, migraines, and rheumatoid arthritis. It may also be used to close a patent ductus arteriosus in a premature baby. It can be used by mouth or intravenously. It typically begins working within an hour. Common side effects include heartburn and a rash. Compared to other NSAIDs, it may have other side effects such as gastrointestinal bleeding. It increases the risk of heart failure, kidney failure, and liver failure. At low doses, it does not appear to increase the risk of heart attack; however, at higher doses it may. Ibuprofen can also worsen asthma. While whether it is safe in early pregnancy is unclear, it appears to be harmful in later pregnancy, so is not recommended. Like other NSAIDs, it works by inhibiting the production of prostaglandins by decreasing the activity of the enzyme cyclooxygenase (COX). Ibuprofen is a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspirin
Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat include Kawasaki disease, pericarditis, and rheumatic fever. Aspirin is also used long-term to help prevent further heart attacks, ischaemic strokes, and blood clots in people at high risk. For pain or fever, effects typically begin within 30 minutes. Aspirin works similarly to other NSAIDs but also suppresses the normal functioning of platelets. One common adverse effect is an upset stomach. More significant side effects include stomach ulcers, stomach bleeding, and worsening asthma. Bleeding risk is greater among those who are older, drink alcohol, take other NSAIDs, or are on other blood thinners. Aspirin is not recommended in the last part of pregnancy. It is not generally recommended in children with infections because of the risk of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EGF-like Domain
The EGF-like domain is an evolutionary conserved protein domain, which derives its name from the epidermal growth factor where it was first described. It comprises about 30 to 40 amino-acid residues and has been found in a large number of mostly animal proteins. Most occurrences of the EGF-like domain are found in the extracellular domain of membrane-bound proteins or in proteins known to be secreted. An exception to this is the prostaglandin-endoperoxide synthase. The EGF-like domain includes 6 cysteine residues which in the epidermal growth factor have been shown to form 3 disulfide bonds. The structures of 4-disulfide EGF-domains have been solved from the laminin and integrin proteins. The main structure of EGF-like domains is a two-stranded β-sheet followed by a loop to a short C-terminal, two-stranded β-sheet. These two β-sheets are usually denoted as the major (N-terminal) and minor (C-terminal) sheets. EGF-like domains frequently occur in numerous tandem copies in pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dalton (unit)
The dalton or unified atomic mass unit (symbols: Da or u) is a non-SI unit of mass widely used in physics and chemistry. It is defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. The atomic mass constant, denoted ''m''u, is defined identically, giving . This unit is commonly used in physics and chemistry to express the mass of atomic-scale objects, such as atoms, molecules, and elementary particles, both for discrete instances and multiple types of ensemble averages. For example, an atom of helium-4 has a mass of . This is an intrinsic property of the isotope and all helium-4 atoms have the same mass. Acetylsalicylic acid (aspirin), , has an average mass of approximately . However, there are no acetylsalicylic acid molecules with this mass. The two most common masses of individual acetylsalicylic acid molecules are , having the most common isotopes, and , in which one carbon is carbon-13. The molecular mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytochrome C Oxidase
The enzyme cytochrome c oxidase or Complex IV, (was , now reclassified as a translocasEC 7.1.1.9 is a large transmembrane protein complex found in bacteria, archaea, and mitochondria of eukaryotes. It is the last enzyme in the respiratory electron transport chain of cells located in the membrane. It receives an electron from each of four cytochrome c molecules and transfers them to one oxygen molecule and four protons, producing two molecules of water. In addition to binding the four protons from the inner aqueous phase, it transports another four protons across the membrane, increasing the transmembrane difference of proton electrochemical potential, which the ATP synthase then uses to synthesize ATP. Structure The complex The complex is a large integral membrane protein composed of several metal prosthetic sites and 14 protein subunits in mammals. In mammals, eleven subunits are nuclear in origin, and three are synthesized in the mitochondria. The complex contains two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
