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Epoxyeicosatrienoic Acid
The epoxyeicosatrienoic acids or EETs are signaling molecules formed within various types of cells by the metabolism of arachidonic acid by a specific subset of cytochrome P450 enzymes, termed cytochrome P450 epoxygenases. They are nonclassic eicosanoids. EETs are generally short-lived, being rapidly converted from epoxides to less active or inactive dihydroxy-eicosatrienoic acids (diHETrEs) by a widely distributed cellular enzyme, soluble epoxide hydrolase (sEH), also termed epoxide hydrolase 2. The EETs consequently function as transiently acting, short-range hormones; that is, they work locally to regulate the function of the cells that produce them (i.e. they are Autocrine signalling, autocrine agents) or of nearby cells (i.e. they are Paracrine signalling, paracrine agents). The EETs have been most studied in animal models where they show the ability to lower blood pressure possibly by a) stimulating arterial Vasodilator, vasorelaxation and b) inhibiting the kidney's rete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eicosatetraenoic Acid
Eicosatetraenoic acid (ETA) designates any straight chain tetra-unsaturated 20-carbon fatty acid. These compound are classified as polyunsaturated fatty acids (PUFA). The pure compounds, which are encountered rarely, are colorless oils. Two isomers, both of them essential fatty acids, are of particular interest: * ''all-cis''-5,8,11,14-eicosatetraenoic acid is an ω-6 fatty acid with the trivial name arachidonic acid. It is formed by a desaturation of dihomo-gamma-linolenic acid (DGLA, 20:3 ω-6). * ''all-cis''-8,11,14,17-eicosatetraenoic acid is an ω-3 fatty acid. It is an intermediate between stearidonic acid (18:4 ω-3) and eicosapentaenoic acid (EPA, 20:5 ω-3) Some chemistry sources define 'arachadonic acid' to designate any of the eicosatetraenoic acids. However, almost all writings in biology, medicine, and nutrition limit the use of the term 'arachidonic acid' to ''all-cis''-5,8,11,14-eicosatetraenoic acid (ω-6). Precursors to eicosanoids Eicosanoids, a diverse fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP2C19
Cytochrome P450 2C19 (abbreviated CYP2C19) is an enzyme protein. It is a member of the CYP2C subfamily of the cytochrome P450 mixed-function oxidase system. This subfamily includes enzymes that catalyze metabolism of xenobiotics, including some proton pump inhibitors and antiepileptic drugs. In humans, it is the ''CYP2C19'' gene that encodes the CYP2C19 protein. CYP2C19 is a liver enzyme that acts on at least 10% of drugs in current clinical use, most notably the antiplatelet treatment clopidogrel (Plavix), drugs that treat pain associated with ulcers, such as omeprazole, antiseizure drugs such as mephenytoin, the antimalarial proguanil, and the anxiolytic diazepam. CYP2C19 has been annotated as (R)-limonene 6-monooxygenase and (S)-limonene 6-monooxygenase in UniProt. Function The gene encodes a member of the cytochrome P450 superfamily of enzymes. Enzymes in the CYP2C subfamily, including CYP2C19, account for approximately 20% of cytochrome P450 in the adult liver. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP2C9
Cytochrome P450 family 2 subfamily C member 9 (abbreviated CYP2C9) is an enzyme protein. The enzyme is involved in the metabolism, by oxidation, of both xenobiotics, including drugs, and endogenous compounds, including fatty acids. In humans, the protein is encoded by the ''CYP2C9'' gene. The gene is highly polymorphic, which affects the efficiency of the metabolism by the enzyme. Function CYP2C9 is a crucial cytochrome P450 enzyme, which plays a significant role in the metabolism, by oxidation, of both xenobiotic and endogenous compounds. CYP2C9 makes up about 18% of the cytochrome P450 protein in liver microsomes. The protein is mainly expressed in the liver, duodenum, and small intestine. About 100 therapeutic drugs are metabolized by CYP2C9, including drugs with a narrow therapeutic index such as warfarin and phenytoin, and other routinely prescribed drugs such as acenocoumarol, tolbutamide, losartan, glipizide, and some nonsteroidal anti-inflammatory drugs. By contra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP2C8
Cytochrome P4502C8 (CYP2C8) is a member of the cytochrome P450 mixed-function oxidase system involved in the metabolism of xenobiotics in the body. Cytochrome P4502C8 also possesses epoxygenase activity, i.e. it metabolizes long-chain polyunsaturated fatty acids, e.g. arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, and linoleic acid to their biologically active epoxides. Ligands Following is a table of selected substrates, inducers and inhibitors of 2C8. Inhibitors of CYP2C8 can be classified by their potency, such as: * Strong inhibitor being one that causes at least a five-fold increase in the plasma AUC values, or more than 80% decrease in clearance. * Moderate inhibitor being one that causes at least a two-fold increase in the plasma AUC values, or 50-80% decrease in clearance. * Weak inhibitor being one that causes at least a 1.25-fold but less than two-fold increase in the plasma AUC values, or 20-50% decrease in clearance. Retrieved on July 2011 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP3A4
Cytochrome P450 3A4 (abbreviated CYP3A4) () is an important enzyme in the body, mainly found in the liver and in the intestine, which in humans is encoded by ''CYP3A4'' gene. It organic redox reaction, oxidizes small foreign organic molecules (xenobiotics), such as toxins or drugs, so that they can be removed from the body. It is highly homologous to CYP3A5, another important CYP3A enzyme. While many drugs are deactivated by CYP3A4, there are also some drugs that are ''activated'' by the enzyme. Some substances, such as some drugs and furanocoumarins present in grapefruit juice, interfere with the action of CYP3A4. These substances will, therefore, either amplify or weaken the action of those drugs that are modified by CYP3A4. CYP3A4 is a member of the cytochrome P450 family of oxidizing enzymes. Several other members of this family are also involved in drug metabolism, but CYP3A4 is the most common and the most versatile one. Like all members of this family, it is a hemoprote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allotropes Of Oxygen
There are several known allotropy, allotropes of oxygen. The most familiar is oxygen, molecular oxygen (), present at significant levels in Atmosphere of Earth, Earth's atmosphere and also known as dioxygen or triplet oxygen. Another is the highly reactive ozone (). Others are: *Atomic oxygen (), a Radical (chemistry), free radical. *Singlet oxygen (), one of two metastable states of molecular oxygen. *Tetraoxygen (), another metastable form. *Solid oxygen, existing in six variously colored phases, of which one is octaoxygen (, red oxygen) and another one metallic (ζ-oxygen). Atomic oxygen Atomic oxygen, denoted O or O1, is very reactive, as the individual atoms of oxygen tend to quickly bond with nearby molecules. Its lowest-energy electronic state is a Triplet state, spin triplet, designated by the term symbol 3P. On Earth's surface, it exists naturally for a very short time. In outer space, the presence of ample ultraviolet radiation results in a low Earth orbit atmosphere in w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudogene
Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Pseudogenes can be formed from both protein-coding genes and non-coding genes. In the case of protein-coding genes, most pseudogenes arise as superfluous copies of functional genes, either directly by gene duplication or indirectly by Reverse transcriptase, reverse transcription of an mRNA transcript. Pseudogenes are usually identified when genome sequence analysis finds gene-like sequences that lack regulatory sequences or are incapable of producing a functional product. Pseudogenes are a type of junk DNA. Most non-bacterial genomes contain many pseudogenes, often as many as functional genes. This is not surprising, since various biological processes are expected to accidentally create pseudogenes, and there are no specialized mechanisms to remove them from genomes. Eventually pseudogenes may be deleted from their genomes by chance of DNA replication or DNA repair errors, or they may accumulate so many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaea
Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even though the domain Archaea Cladistics, cladistically includes eukaryotes, the term "archaea" (: archaeon , from the Greek "ἀρχαῖον", which means ancient) in English still generally refers specifically to prokaryotic members of Archaea. Archaea were initially Taxonomy (biology), classified as bacteria, receiving the name archaebacteria (, in the Archaebacteria Kingdom (biology), kingdom), but this term has fallen out of use. Archaeal cells have unique properties separating them from Bacteria and Eukaryote, Eukaryota. Archaea are further divided into multiple recognized phylum, phyla. Classification is difficult because most have not been Isolation (microbiology), isolated in a laboratory and have been detected only by their Gene, gene s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiomer
In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities which are mirror images of each other and non-superposable. Enantiomer molecules are like right and left hands: one cannot be superposed onto the other without first being converted to its mirror image. It is solely a relationship of chirality (chemistry), chirality and the permanent three-dimensional relationships among molecules or other chemical structures: no amount of re-orientation of a molecule as a whole or conformational isomerism, conformational change converts one chemical into its enantiomer. Chemical structures with chirality rotate plane-polarized light. A mixture of equal amounts of each enantiomer, a ''racemic mixture'' or a ''racemate'', does not rotate light. Stereoisomers include both enantiomers and diastereomers. Diaste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regioisomer
In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is a compound that contains the same number and type of atoms, but with a different connectivity (i.e. arrangement of bonds) between them. The term metamer was formerly used for the same concept. For example, butanol , methyl propyl ether , and diethyl ether have the same molecular formula but are three distinct structural isomers. The concept applies also to polyatomic ions with the same total charge. A classical example is the cyanate ion and the fulminate ion . It is also extended to ionic compounds, so that (for example) ammonium cyanate and urea are considered structural isomers,William F. Bynum, E. Janet Browne, Roy Porter (2014)''Dictionary of the History of Science'' page 218. and so are methylammonium formate and ammonium acetate . Structural isomerism is the most radical type of isomerism. It is opposed to stereoisomerism, in which the atoms and bonding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Nomenclature
Chemical nomenclature is a set of rules to generate systematic name#In chemistry, systematic names for chemical compounds. The nomenclature used most frequently worldwide is the one created and developed by the International Union of Pure and Applied Chemistry (IUPAC). IUPAC Nomenclature ensures that each compound (and its various isomers) have only one formally accepted name known as the systematic IUPAC name. However, some compounds may have alternative names that are also accepted, known as the preferred IUPAC name which is generally taken from the common name (chemistry), common name of that compound. Preferably, the name should also represent the structure or chemistry of a compound. For example, the main constituent of vinegar, white vinegar is , which is commonly called acetic acid and is also its recommended IUPAC name, but its formal, systematic IUPAC name is ethanoic acid. The IUPAC's rules for naming organic compound, organic and inorganic compounds are contained in two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
