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Cardenolides
A cardenolide is a type of steroid. Many plants contain derivatives, collectively known as cardenolides, including many in the form of cardenolide glycosides (cardenolides that contain structural groups derived from sugars). Cardenolide glycosides are often toxic; specifically, they are heart-arresting. Cardenolides are toxic to animals through inhibition of the enzyme Na+/K+-ATPase, which is responsible for maintaining the sodium and potassium ion gradients across the cell membranes. Etymology The term derives from ''card-'' "heart" (from Greek καρδία ''kardiā'') and the suffix , referring to the lactone ring with double bond at C17. Cardenolides are a class of steroids (or aglycones if viewed as cardiac glycoside constituents), and cardenolides are a subtype of this class (see MeSH D codes list). Structure Cardenolides are C(23)-steroids with methyl groups at C-10 and C-13 and a five-membered lactone (specifically a butenolide) at C-17. They are aglycone constituents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monarch Butterfly
The monarch butterfly or simply monarch (''Danaus plexippus'') is a milkweed butterfly (subfamily Danainae) in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. It is among the most familiar of List of butterflies of North America, North American butterflies and an iconic pollinator, although it is not an especially effective pollinator of milkweeds. Its wings feature an easily recognizable black, orange, and white pattern, with a wingspan of . A Müllerian mimic, the viceroy butterfly, is similar in color and pattern, but is markedly smaller and has an extra black stripe across each hindwing. The eastern North American monarch population is notable for its annual southward late-summer/autumn instinctive Monarch butterfly migration, migration from the northern and central United States and southern Canada to Florida and Mexico. During the fall migration, monarchs cover thousands of miles, with a co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queen (butterfly)
The queen butterfly (''Danaus gilippus'') is a North and South American butterfly in the family Nymphalidae with a wingspan of . It is orange or brown with black wing borders and small white forewing spots on its Dorsum (biology), dorsal wing surface, and reddish ventral wing surface fairly similar to the dorsal surface. The ventral hindwings have black veins and small white spots in a black border. The male has a black androconial scent patch on its dorsal hindwings. It can be found in meadows, fields, marshes, deserts, and at the edges of forests. This species is possibly a close relative to the similarly colored soldier butterfly (or tropical queen, ''Danaus eresimus, D. eresimus''), in any case, it is not close to the plain tiger (''Danaus chrysippus, D. chrysippus'', African queen) as was long believed. There are seven subspecies. Females lay one egg at a time on larval host plants. Larvae use these plants as a food source, whereas adult butterflies feed mainly on nectar fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danaus Chrysippus
''Danaus chrysippus'', also known as the plain tiger, African queen, or African monarch, is a medium-sized butterfly widespread in Asia, Australia and Africa. It belongs to the Danainae subfamily of the brush-footed butterfly Family (biology), family Nymphalidae. Danainae primarily consume plants in the genus ''Asclepias'', more commonly called milkweed. Milkweed contains toxic compounds, cardenolides, which are often consumed and stored by many butterflies. Because of their emetic properties, the plain tiger is Palatability, unpalatable to most predators. As a result, its colouration is widely mimicry, mimicked by other species of butterflies. The plain tiger inhabits a wide variety of habitats, although it is less likely to thrive in jungle-like conditions and is most often found in drier, wide-open areas. ''D. chrysippus'' encompasses three main subspecies: ''D. c. alcippus, D. c. chrysippus,'' and ''D. c. orientis.'' These subspecies are found co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Glycoside
Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump. Their beneficial medical uses include treatments for congestive heart failure and cardiac arrhythmias; however, their relative toxicity prevents them from being widely used. Most commonly found as defensive poisons in several plant genera such as ''Digitalis'' (the foxgloves) and '' Asclepias'' (the milkweeds), these compounds nevertheless have a diverse range of biochemical effects regarding cardiac cell function and have also been suggested for use in cancer treatment. Classification General structure The general structure of a cardiac glycoside consists of a steroid molecule attached to a sugar (glycoside) and an R group. The steroid nucleus consists of four fused rings to which other functional groups such as methyl, hydroxyl, and aldehyde groups can be attached to influence th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ouabain
Ouabain or (from Somali ''waabaayo'', "arrow poison" through French ''ouabaïo'') also known as g-strophanthin, is a plant derived toxic substance that was traditionally used as an arrow poison in eastern Africa for both hunting and warfare. Ouabain is a cardiac glycoside and, in lower doses, can be used medically to treat hypotension and some arrhythmias. It acts by inhibiting the Na/K-ATPase, also known as the sodium–potassium ion pump. However, adaptations to the alpha-subunit of the -ATPase via amino acid substitutions, have been observed in certain species, namely some herbivore insect species, that have resulted in toxin resistance. It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities. Sources Ouabain can be found in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strophanthidin
k-Strophanthidin is a cardenolide found in species of the genus ''Strophanthus''. It is the aglycone of k-strophanthin, an analogue of ouabain. k-strophanthin is found in the ripe seeds of Strophanthus kombé and in the lily Convallaria. K-Strophantidin can be differentiated into: * k-Strophanthin-α, h-Strophanthin, Cymarin, Strophanthidin-D-cymarosid (CAS: 508-77-0) * k-Strophanthin-β, k-Strophanthin, Strophosid, Strophanthidin-glucocymarosid (CAS: 560-53-2) * k-Strophanthin-γ,k-Strophanthosid, Strophanthidin-diglucocymarosid (CAS: 33279-57-1) * Convallatoxin or Strophanthidin-L-rhamnosid (CAS: 508-75-8) * Convallosid or Strophanthidin-glucorhamnosid (CAS: 13473-51-3) Strophantidin is a cardiac glycoside which mechanism of action is similar to Digitalis, Ouabain and digitoxin. It specifically inhibits the membrane protein Na+/ K+ ATPase in muscle tissue (heart) which can lead to Ca2+ overload, diastolic dysfunction, arrhythmias and ultimately to heart failure and death. N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digitoxin
Digitoxin is a cardiac glycoside used for the treatment of heart failure and certain kinds of heart arrhythmia. It is a phytosteroid and is similar in structure and effects to digoxin, though the effects are longer-lasting. Unlike digoxin, which is eliminated from the body via the kidneys, it is eliminated via the liver, and so can be used in patients with poor or erratic kidney function. While several controlled trials have shown digoxin to be effective in a proportion of patients treated for heart failure, the evidence base for digitoxin is not as strong, although it is presumed to be similarly effective. Medical uses Digitoxin is used for the treatment of heart failure, especially in people with impaired kidney function. It is also used to treat certain kinds of heart arrhythmia, such as atrial fibrillation. Contraindications Contraindications include * problems with the heart rhythm, such as severe bradycardia (slow heartbeat), ventricular tachycardia (fast heartbeat caused ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digitoxigenin
Digitoxigenin, a cardenolide, is the aglycone of digitoxin. Digitoxigenin can be used to prepare actodigin. In Lednicer's book on steroids, it is made from deoxycholic acid Deoxycholic acid is a bile acid. Deoxycholic acid is one of the secondary bile acids, which are metabolic byproducts of intestinal bacteria. The two primary bile acids secreted by the liver are cholic acid and chenodeoxycholic acid. Bacteria m .... References Cardenolides Diols {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MeSH D04
Medical Subject Headings (MeSH) is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences. It serves as a thesaurus of index terms that facilitates searching. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed article database and by NLM's catalog of book holdings. MeSH is also used by ClinicalTrials.gov registry to classify which diseases are studied by trials registered in ClinicalTrials. MeSH was introduced in the 1960s, with the NLM's own index catalogue and the subject headings of the Quarterly Cumulative Index Medicus (1940 edition) as precursors. The yearly printed version of MeSH was discontinued in 2007; MeSH is now available only online. It can be browsed and downloaded free of charge through PubMed. Originally in English, MeSH has been translated into numerous other languages and allows retrieval of documents from different origins. Structure MeSH vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium In Biology
Potassium is the main intracellular ion for all types of cells, while having a major role in maintenance of fluid and electrolyte balance. Potassium is necessary for the function of all living cells and is thus present in all plant and animal tissues. It is found in especially high concentrations within plant cells, and in a mixed diet, it is most highly concentrated in fruits. The high concentration of potassium in plants, associated with comparatively very low amounts of sodium there, historically resulted in potassium first being isolated from the ashes of plants (potash), which in turn gave the element its modern name. The high concentration of potassium in plants means that heavy crop production rapidly depletes soils of potassium, and agricultural fertilizers consume 93% of the potassium chemical production of the modern world economy. The functions of potassium and sodium in living organisms are quite different. Animals, in particular, employ sodium and potassium different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxic
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell ( cytotoxicity) or an organ such as the liver ( hepatotoxicity). Sometimes the word is more or less synonymous with poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to bypass animal testing, while maintaining the concept of toxicity endpoints. Etymology In Ancient Greek medical literature, the adjective ''τοξικόν'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
