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Phosphorothioate
Thiophosphates (or phosphorothioates, PS) are chemical compounds and anions with the general chemical formula (''x'' = 0, 1, 2, or 3) and related derivatives where organic groups are attached to one or more O or S. Thiophosphates feature tetrahedral phosphorus(V) centers. Organic Organothiophosphates are a subclass of organophosphorus compounds that are structurally related to the inorganic thiophosphates. Common members have formulas of the type (RO)3−''x''R''x''PS and related compounds where RO is replaced by RS. Many of these compounds are used as insecticides, some have medical applications, and some have been used as oil additives.J. Svara, N. Weferling, T. Hofmann "Phosphorus Compounds, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2006. Oligonucleotide phosphorothioates (OPS) are modified oligonucleotides where one of the oxygen atoms in the phosphate moiety is replaced by sulfur. They are the basis of antisense therapy, e.g., the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Monothiophosphate
Sodium monothiophosphate, or sodium phosphorothioate, is an inorganic compound with the molecular formula Na3PO3S(H2O)x. All are white solids. The anhydrous material (x = 0) decomposes without melting at 120-125 °C. More common is the dodecahydrate. A nonahydrate is also known. Related salts are the ''di''thiophosphate Na3PS2O2.11H2O, ''tri''thiophosphate Na3PS3O.11H2O, and ''tetra''thiophosphate Na3PS4.8H2O. Preparation Sodium monothiophosphate is prepared by the base hydrolysis of thiophosphoryl chloride using aqueous sodium hydroxide: :PSCl3 + 6 NaOH + 9 H2O → Na3PO3S.(H2O)12 + 3 NaCl This reaction affords the dodecahydrate, which is easily dehydrated. Partial dehydration over 6.5 M H2SO4 gives the nonahydrate. Under flowing N2, the anhydrous salt is formed. Sodium phosphorothiolate decomposes at neutral pH. Silicone grease Silicone grease, sometimes called dielectric grease, is a waterproof grease made by combining a silicone oil with a thickener. Most co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fomivirsen
Fomivirsen (brand name Vitravene) is an antisense therapy, antisense antiviral drug that was used in the treatment of cytomegalovirus retinitis (CMV) in immunocompromised patients, including those with AIDS. It was administered via intraocular injection. It was discovered at the NIH and was licensed and initially drug development, developed by Ionis Pharmaceuticals, Isis Pharmaceuticals, which subsequently licensed it to Novartis. It was licensed by the FDA for CMV in Aug 1998, and was the first antisense drug that was approved. Novartis withdrew the marketing authorization in the EU in 2002 and in the US in 2006. The drug was withdrawn because while there was a high unmet need for drugs to treat CMV when the drug was initially discovered and developed due to the CMV arising in people with AIDS, the development of HAART dramatically reduced the number of cases of CMV. It is an antisense oligonucleotide -- a synthetic 21 member oligonucleotide with thiophosphate, phosphorothioat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorpyrifos
Chlorpyrifos (CPS), also known as Chlorpyrifos ethyl, is an organophosphate pesticide that has been used on crops, animals, and buildings, and in other settings, to kill several pests, including insects and worms. It acts on the nervous systems of insects by inhibiting the acetylcholinesterase enzyme. Chlorpyrifos was patented in 1966 by Dow Chemical Company. Chlorpyrifos is considered moderately hazardous to humans (Class II) by the World Health Organization based on acute toxicity information dating to 1999. Exposure surpassing recommended levels has been linked to neurological effects, persistent developmental disorders, and autoimmune disorders. Exposure during pregnancy may harm the mental development of children. In the United Kingdom, the use of chlorpyrifos was banned as of 1 April 2016 (with one minor exception). As of 2020, chlorpyrifos and chlorpyrifos-methyl were banned throughout the European Union, where they may no longer be used. The EU also applied to have ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mipomersen
Mipomersen (INN; trade name Kynamro) is a drug used to treat homozygous familial hypercholesterolemia and is administered by subcutaneous injection. There is a serious risk of liver damage from this drug and it can only be prescribed in the context of a risk management plan. Indications Kynamro is used to treat homozygous familial hypercholesterolemia and is administered by injection. It cannot be freely prescribed; instead every person put on mipomersen is enrolled in a Risk Evaluation and Mitigation Strategies (REMS) program approved by the FDA. Pregnancy and lactation Mipomersen is pregnancy category B; women who are pregnant or intending to become pregnant should only use this drug if needed. It is unknown if it is secreted in human breast milk, but it was found to be secreted in the breast milk of rats. Contraindications The drug is contraindicated in people with moderate to severe liver impairment, active liver diseases, and unexplained high levels of transaminas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alicaforsen
Alicaforsen (trade name Camligo) is an antisense oligonucleotide therapeutic that targets the messenger RNA for the production of human ICAM-1 receptor and is being developed for the treatment of acute disease flares in moderate to severe Inflammatory Bowel Disease (IBD). Alicaforsen inhibits ICAM-1 production, which is an important adhesion molecule involved in leukocyte migration and trafficking to the site of inflammation. Hitherto, alicaforsen has been granted orphan drug designation and is prescribed as an unlicensed medicine in accordance with international regulation, for the treatment of pouchitis and left-sided ulcerative colitis. Given the positive results from an open-label trial and one case series in patients with chronic refractory pouchitis, US FDA has agreed to a rolling submission for a license application for the treatment of pouchitis. It was discovered by Ionis Pharmaceuticals (formerly Isis Pharmaceuticals) and in 2017 Atlantic Healthcare plc took over th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antisense Therapy
Antisense therapy is a form of treatment that uses antisense oligonucleotides (ASOs) to target messenger RNA (mRNA). ASOs are capable of altering mRNA expression through a variety of mechanisms, including ribonuclease H mediated decay of the pre-mRNA, direct steric blockage, and exon content modulation through splicing site binding on pre-mRNA. Several ASOs have been approved in the United States, the European Union, and elsewhere. Nomenclature The common stem for antisense oligonucleotides drugs is -rsen. The substem -virsen designates antiviral antisense oligonucleotides. Pharmacokinetics and pharmacodynamics Half-life and stability ASO-based drugs employ highly modified, single-stranded chains of synthetic nucleic acids that achieve wide tissue distribution with very long half-lives. For instance, many ASO-based drugs contain phosphorothioate substitutions and 2' sugar modifications to inhibit nuclease degradation enabling vehicle-free delivery to cells. ''In vivo' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fast Ion Conductor
In materials science, fast ion conductors are solid conductors with highly mobile ions. These materials are important in the area of solid state ionics, and are also known as solid electrolytes and superionic conductors. These materials are useful in batteries and various sensors. Fast ion conductors are used primarily in solid oxide fuel cells. As solid electrolytes they allow the movement of ions without the need for a liquid or soft membrane separating the electrodes. The phenomenon relies on the hopping of ions through an otherwise rigid crystal structure. Mechanism Fast ion conductors are intermediate in nature between crystalline solids which possess a regular structure with immobile ions, and liquid electrolytes which have no regular structure and fully mobile ions. Solid electrolytes find use in all solid-state supercapacitors, batteries, and fuel cells, and in various kinds of chemical sensors. Classification In solid electrolytes (glasses or crystals), the ionic con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyanion
An oxyanion, or oxoanion, is an ion with the generic formula (where A represents a chemical element and O represents an oxygen atom). Oxyanions are formed by a large majority of the chemical elements. The formulae of simple oxyanions are determined by the octet rule. The corresponding oxyacid of an oxyanion is the compound . The structures of condensed oxyanions can be rationalized in terms of AO''n'' polyhedral units with sharing of corners or edges between polyhedra. The oxyanions (specifically, phosphate and polyphosphate esters) adenosine monophosphate ( AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP) are important in biology. Monomeric oxyanions The formula of monomeric oxyanions, , is dictated by the oxidation state of the element A and its position in the periodic table. Elements of the first row are limited to a maximum coordination number of 4. However, none of the first row elements has a monomeric oxyanion with that coordination number. Instead, ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription (genetics)
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). mRNA comprises only 1–3% of total RNA samples. Less than 2% of the human genome can be transcribed into mRNA ( Human genome#Coding vs. noncoding DNA), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: # RNA polymerase, together with one or more general transcription factors, binds to promot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrate
Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. Structure The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1. This charge results from a combination formal charge in which each of the three oxygens carries a − charge, whereas the nitrogen carries a +1 charge, all these adding up to formal charge of the polyatomic nitrate ion. This arrangement is commonly used as an example of resonance. Like the isoelectronic carbonate ion, the nitrate ion can be represented by resonance structures: Dietary nitrate A rich source of inorganic nitrate in the human diets come from leafy green foods, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid ( American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula . It is a colorless, odorless and viscous liquid that is miscible with water. Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air. Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid, but to the contrary dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is released; thus the reverse procedure of adding water to the acid should not be performed since the heat released ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
