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Tetrandrine
Tetrandrine, a bis-benzylisoquinoline alkaloid, is a calcium channel blocker. It is isolated from the plant ''Stephania tetrandra'', and other Chinese and Japanese herbs. Pharamacology It has anti-inflammatory, immunologic and antiallergenic effects. It inhibits the degranulation of mast cells. It has a quinidine-like anti-arrhythmic effect. It has vasodilatory properties and can therefore reduce blood pressure. Tetrandrine may have potential use for the treatment of liver disease and liver cancer. Tetrandrine has potential therapeutic value to prevent excess scarring/fibrosis in conjunctiva following trabeculectomy Trabeculectomy is a surgical procedure used in the treatment of glaucoma to relieve intraocular pressure by removing part of the human eye, eye's trabecular meshwork and adjacent structures. It is the most common glaucoma surgery performed and all ... or in patients with severe conjunctival inflammation. Tetrandrine has anti-inflammatory and anti-fibrogenic acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephania Tetrandra
''Stephania tetrandra'' is a herbaceous perennial vine of the family Menispermaceae native to China and Taiwan. It grows from a short, woody caudex, climbing to a height of around three meters. The leaves are arranged spirally on the stem, and are peltate, i.e. with the leaf petiole attached near the centre of the leaf. Its root is used in traditional Chinese medicine (TCM). Distribution and habitat ''Stephania tetrandra'' occurs in shrublands at village margins, open fields, and roadsides in South Central and East China in Anhui, Fujian, Guangdong, Guangxi, Hainan, Hubei, Hunan, Jiangxi, and Zhejiang provinces, and in Taiwan. Etymology in Chinese medicine ''Stephania tetrandra'' is among the 50 fundamental herbs used in TCM. The standard pinyin according to the ''Chinese erbalPharmacopia of the People's Republic of China'' () is: fen fang ji (), but it is more commonly known as ''Han Fang ji'' (). Traditional medicine Fen fang ji is used in traditional Chinese medicine to dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrandrine Proposed Biosynthesis
Tetrandrine, a bis-benzylisoquinoline alkaloid, is a calcium channel blocker. It is isolated from the plant ''Stephania tetrandra'', and other Chinese and Japanese herbs. Pharamacology It has anti-inflammatory, immunologic and antiallergenic effects. It inhibits the degranulation of mast cells. It has a quinidine-like anti-arrhythmic effect. It has vasodilatory Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, ... properties and can therefore reduce blood pressure. Tetrandrine may have potential use for the treatment of liver disease and liver cancer. Tetrandrine has potential therapeutic value to prevent excess scarring/fibrosis in conjunctiva following trabeculectomy or in patients with severe conjunctival inflammation. Tetrandrine has anti-inflammatory and anti-fibrogenic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzylisoquinoline
Substitution of the heterocycle isoquinoline at the C1 position by a benzyl group provides 1‑benzylisoquinoline, the most widely examined of the numerous benzylisoquinoline structural isomers. The 1-benzylisoquinoline moiety can be identified within numerous compounds of pharmaceutical interest, such as moxaverine; but most notably it is found within the structures of a wide variety of plant natural products, collectively referred to as benzylisoquinoline alkaloids. This class is exemplified in part by the following compounds: papaverine, noscapine, codeine, morphine, apomorphine, berberine, tubocurarine. Biosynthesis (''S'')-Norcoclaurine (higenamine) has been identified as the central 1-benzyl-tetrahydro-isoquinoline precursor from which numerous complex biosynthetic pathways eventually emerge. These pathways collectively lead to the structurally disparate compounds comprising the broad classification of plant natural products referred to as benzylisoquinoline alkaloids (BIA), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.Chemical Encyclopedia: alkaloids xumuk.ru Alkaloids are produced by a large variety of organisms including , , Medicinal plant, plants, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Channel Blocker
Calcium channel blockers (CCB), calcium channel antagonists or calcium antagonists are a group of medications that disrupt the movement of calcium () through calcium channels. Calcium channel blockers are used as antihypertensive drugs, i.e., as medications to decrease blood pressure in patients with hypertension. CCBs are particularly effective against large vessel stiffness, one of the common causes of elevated systolic blood pressure in elderly patients. Calcium channel blockers are also frequently used to alter heart rate (especially from atrial fibrillation), to prevent peripheral and cerebral vasospasm, and to reduce chest pain caused by angina pectoris. N-type, L-type, and T-type voltage-dependent calcium channels are present in the zona glomerulosa of the human adrenal gland, and CCBs can directly influence the biosynthesis of aldosterone in adrenocortical cells, with consequent impact on the clinical treatment of hypertension with these agents. CCBs have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mast Cells
A mast cell (also known as a mastocyte or a labrocyte) is a resident cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a part of the immune and neuroimmune systems. Mast cells were discovered by Paul Ehrlich in 1877. Although best known for their role in allergy and anaphylaxis, mast cells play an important protective role as well, being intimately involved in wound healing, angiogenesis, immune tolerance, defense against pathogens, and vascular permeability in brain tumours. The mast cell is very similar in both appearance and function to the basophil, another type of white blood cell. Although mast cells were once thought to be tissue-resident basophils, it has been shown that the two cells develop from different hematopoietic lineages and thus cannot be the same cells. Structure Mast cells are very similar to basophil granulocytes (a class of white blo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinidine
Quinidine is a class IA antiarrhythmic agent used to treat heart rhythm disturbances. It is the enantiomer of antimalarial agent quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. As of 2019, its IV formulation is no longer being manufactured for use in the United States. Medical uses Quinidine is occasionally used as a class I antiarrhythmic agent to prevent ventricular arrhythmias, particularly in Brugada Syndrome, although its safety in this indication is uncertain. It reduces the recurrence of atrial fibrillation after patients undergo cardioversion, but it has proarrhythmic effects and trials suggest that it may lead to an overall increased mortality in these patients. Quinidine is also used to treat short QT syndrome. Eli Lilly has discontinued manufacture of parenteral quinidine gluconate in the US, and its future availability in many countries is uncertain. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasodilatory
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, which is the narrowing of blood vessels. When blood vessels dilate, the flow of blood is increased due to a decrease in vascular resistance and increase in cardiac output. Therefore, dilation of arterial blood vessels (mainly the arterioles) decreases blood pressure. The response may be intrinsic (due to local processes in the surrounding tissue) or extrinsic (due to hormones or the nervous system). In addition, the response may be localized to a specific organ (depending on the metabolic needs of a particular tissue, as during strenuous exercise), or it may be systemic (seen throughout the entire systemic circulation). Endogenous substances and drugs that cause vasodilation are termed vasodilators. Such vasoactivity is necessary for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabeculectomy
Trabeculectomy is a surgical procedure used in the treatment of glaucoma to relieve intraocular pressure by removing part of the human eye, eye's trabecular meshwork and adjacent structures. It is the most common glaucoma surgery performed and allows drainage of aqueous humor from within the eye to underneath the conjunctiva where it is absorbed. This outpatient procedure was most commonly performed under monitored anesthesia care using a retrobulbar block or peribulbar block or a combination of topical and subtenon (Tenon's capsule) anesthesia. Due to the higher risks associated with bulbar blocks, topical analgesia with mild sedation is becoming more common. Rarely general anesthesia will be used, in patients with an inability to cooperate during surgery. Procedure An initial pocket is created under the conjunctiva and Tenon's capsule and the wound bed is treated for several seconds to minutes with mitomycin C (MMC, 0.5–0.2 mg/ml) or 5-fluorouracil (5-FU, 50 mg/ml) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunctival
The conjunctiva is a thin mucous membrane that lines the inside of the eyelids and covers the sclera (the white of the eye). It is composed of non-keratinized, stratified squamous epithelium with goblet cells, stratified columnar epithelium and stratified cuboidal epithelium (depending on the zone). The conjunctiva is highly vascularised, with many microvessels easily accessible for imaging studies. Structure The conjunctiva is typically divided into three parts: Blood supply Blood to the bulbar conjunctiva is primarily derived from the ophthalmic artery. The blood supply to the palpebral conjunctiva (the eyelid) is derived from the external carotid artery. However, the circulations of the bulbar conjunctiva and palpebral conjunctiva are linked, so both bulbar conjunctival and palpebral conjunctival vessels are supplied by both the ophthalmic artery and the external carotid artery, to varying extents. Nerve supply Sensory innervation of the conjunctiva is divided into four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicosis
Silicosis is a form of occupational lung disease caused by inhalation of crystalline silica dust. It is marked by inflammation and scarring in the form of nodular lesions in the upper lobes of the lungs. It is a type of pneumoconiosis. Silicosis (particularly the acute form) is characterized by shortness of breath, cough, fever, and cyanosis (bluish skin). It may often be misdiagnosed as pulmonary edema (fluid in the lungs), pneumonia, or tuberculosis. Using workplace controls, silicosis is almost always a preventable disease. Silicosis resulted in at least 43,000 deaths globally in 2013, down from at least 50,000 deaths in 1990. The name ''silicosis'' (from the Latin ''silex'', or flint) was originally used in 1870 by Achille Visconti (1836–1911), prosector in the Ospedale Maggiore of Milan. The recognition of respiratory problems from breathing in dust dates to ancient Greeks and Romans. Agricola, in the mid-16th century, wrote about lung problems from dust inhalation i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ebola Virus
''Zaire ebolavirus'', more commonly known as Ebola virus (; EBOV), is one of six known species within the genus ''Ebolavirus''. Four of the six known ebolaviruses, including EBOV, cause a severe and often fatal hemorrhagic fever in humans and other mammals, known as Ebola virus disease (EVD). Ebola virus has caused the majority of human deaths from EVD, and was the cause of the 2013–2016 epidemic in western Africa, which resulted in at least suspected cases and confirmed deaths. Ebola virus and its genus were both originally named for Zaire (now the Democratic Republic of the Congo), the country where it was first described, and was at first suspected to be a new "strain" of the closely related Marburg virus. The virus was renamed "Ebola virus" in 2010 to avoid confusion. Ebola virus is the single member of the species ''Zaire ebolavirus'', which is assigned to the genus ''Ebolavirus'', family ''Filoviridae'', order ''Mononegavirales''. The members of the species are cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
