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Bufagin
Bufagin is a toxic steroid C24H34O5 obtained from toad's milk, the poisonous secretion of a skin gland on the back of the neck of a large toad (''Rhinella marina'', synonym ''Bufo marinus'', the cane toad). The toad produces this secretion when it is injured, scared or provoked. Bufagin resembles chemical substances from digitalis in physiological activity and chemical structure. ''Bufagin'' also refers to any of several similar substances found as components of the mixture bufotoxin in secretions of other toads, as well as plants and mushrooms. Chemistry Bufagin and bufagins are bufadienolide derivatives. This means they are steroids with a pyran- (delta-)lactone ring attached to ring D (the five-membered one). The difference to digitalis compounds is that the latter have a furan- (gamma-)lactone ring that has one carbon atom and one double bond less. Effects of bufagins Some bufagins have effects similar to poisoning by digitalis, having effects on the cardiac muscle, causin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arenobufagin
Arenobufagin is a cardiotoxic bufanolide steroid secreted by the Argentine toad '' Bufo arenarum''. It has effects similar to digitalis, blocking the Na+/K+ pump in heart tissue. Sources The compound arenobufagin is one of the major components of toad venom. It is derived from the dried skin of giant toads, such as ''Bufo gargarizans'' and '' Bufo melanostictus Suhneider''. Arenobufagin is specifically secreted by '' Rhinella arenarum'', which is found in South America. The venom of these toad species contains about 1.75% of arenobufagin. The other major part of the venom consists mostly of similar looking bufagins, which are all toxic steroids. Toads produce their venom when they are scared, injured, or provoked, as a defense mechanism against their predators. History Arenobufagin is a component of a certain toad venom which goes by the name of Chan’su. For centuries, this venom has been used in Chinese traditional medicine in the treatment of liver cancer. Also, it is rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signaling molecules. Hundreds of steroids are found in plants, animals and fungi. All steroids are manufactured in cells from the sterols lanosterol (opisthokonts) or cycloartenol (plants). Lanosterol and cycloartenol are derived from the cyclization of the triterpene squalene. The steroid core structure is typically composed of seventeen carbon atoms, bonded in four " fused" rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring). Steroids vary by the functional groups attached to this four-ring core and by the oxidation state of the rings. Sterols are forms of steroids with a hydroxy group at position three and a skeleton derived from cholestane. ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostate Cancer
Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that surrounds the urethra just below the bladder. It is located in the hypogastric region of the abdomen. To give an idea of where it is located, the bladder is superior to the prostate gland as shown in the image The rectum is posterior in perspective to the prostate gland and the ischial tuberosity of the pelvic bone is inferior. Only those who have male reproductive organs are able to get prostate cancer. Most prostate cancers are slow growing. Cancerous cells may spread to other areas of the body, particularly the bones and lymph nodes. It may initially cause no symptoms. In later stages, symptoms include pain or difficulty urinating, blood in the urine, or pain in the pelvis or back. Benign prostatic hyperplasia may produce similar symptoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oak Toad
The oak toad (''Anaxyrus quercicus'') is a species of toad in the family Bufonidae. It is endemic to the coastal regions of southeastern United States.University of Michigan Museum of Zoology. Retrieved on 21 October 2008. It is regarded as the smallest species of toad in North America, with a length of . Description The oak toad can be identified by its light mid-dorsal stripe, variable brown and black spots, and proportionally large s. One of the most remarkable features of this species is its small adult size relative to other toads.[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cane Toad
The cane toad (''Rhinella marina''), also known as the giant neotropical toad or marine toad, is a large, terrestrial true toad native to South and mainland Central America, but which has been introduced to various islands throughout Oceania and the Caribbean, as well as Northern Australia. It is a member of the genus ''Rhinella'', which includes many true toad species found throughout Central and South America, but it was formerly assigned to the genus ''Bufo''. The cane toad is an old species. A fossil toad (specimen UCMP 41159) from the La Venta fauna of the late Miocene in Colombia is indistinguishable from modern cane toads from northern South America. It was discovered in a floodplain deposit, which suggests the ''R. marina'' habitat preferences have long been for open areas. The cane toad is a prolific breeder; females lay single-clump spawns with thousands of eggs. Its reproductive success is partly because of opportunistic feeding: it has a diet, unusual among anuran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bufo Rubescens
''Rhinella rubescens'' is a species of toad in the family Bufonidae. It is endemic to Brazil. Its natural habitats are moist savanna, subtropical or tropical moist shrubland, subtropical or tropical high-altitude shrubland, rivers, freshwater marshes, pastureland, rural gardens, urban areas, and ponds. It is threatened by habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby .... Its color is a golden orange. References Sources * rubescens Endemic fauna of Brazil Taxonomy articles created by Polbot Amphibians described in 1925 {{Bufonidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marinobufagin
Marinobufagenin (marinobufagin) is a cardiotonic bufadienolide steroid. It can be found in the plasma and urine of human subjects with myocardial infarction, kidney failure, and heart failure. It is also secreted by the toad '' Bufo rubescens'' and other related species such as '' Bufo marinus''. It is a vasoconstrictor with effects similar to digitalis ''Digitalis'' ( or ) is a genus of about 20 species of herbaceous perennial plants, shrubs, and biennials, commonly called foxgloves. ''Digitalis'' is native to Europe, western Asia, and northwestern Africa. The flowers are tubular in shap .... References Vertebrate toxins Epoxides Bufanolides Diols {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese Toad
The Japanese common toad, Japanese warty toad or Japanese toad (''Bufo japonicus'') is a species of toad in the family Bufonidae. It is endemic to Japan. Its natural habitats are subarctic forests, temperate forests, temperate shrubland, swamps, freshwater marshes, intermittent freshwater marshes, freshwater springs, arable land, rural gardens, urban areas, ponds, and irrigated land. Amplexus is the mating behaviour involved in the Japanese common toad during the breeding season. Description The Japanese common toad can reach a snout–to–vent length of up to about , with females being a little larger than males, and toads living in warmer habitats growing larger than those in colder places. The head has a pointed snout and is roughly triangular. The tympanum is elliptical and about as far behind the eye as its longest diameter. The body is robust and the stout forelimbs are about half as long as the hind limbs. The second finger on the hand is the shortest and the third the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chusan Island Toad
The Asiatic toad or Chusan Island toad (''Bufo gargarizans'') is a species of toad endemic to East Asia. The species was previously classified as ''Bufo bufo gargarizans'', a subspecies of the common toad. Distribution and habitat It is common in China (specifically Anhui, Fujian, Gansu, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Inner Mongolia, Jiangsu, Jiangxi, Jilin, Qinghai, Shaanxi, Shandong, Shanxi, Sichuan, and Zhejiang) and portions of the Russian Far East (up north to the Amur River valley and on Sakhalin Island, and east to Transbaikalia in Siberia), but relatively rare on the Korean Peninsula. Asiatic toads are also found on the Miyako Islands of southern Japan, although they have been extirpated from some islands in recent years, possibly including Okinawa. The Miyako subspecies, '' Bufo gargarizans miyakonis'', is also known as the Miyako toad. The Asiatic toad avoids dense forests, but is found in most other habitats, including grasslands, open for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinobufagin
Cinobufagin is a cardiotoxic bufanolide steroid secreted by the Asiatic toad ''Bufo gargarizans''. It has similar effects to digitalis and is used in traditional Chinese medicine. Isolation and purification Cinobufagin, as well as other bufadienolides, can be isolated from the traditional Chinese medicine called ChanSu. ChanSu is made from a multitude of chemicals present in Bufo gargarizans secretions. Resibufogenin can be eluted out with silica gel column chromatography, using a 5:1 ratio of cyclohexane to acetone for the solvent in the mobile phase. Subsequently, cinobufagin and bufalin can be separated and purified using an HPLC column with a 72:28 methanol to water solvent. Yang et al. confirmed this method of isolation for cinobufagin with Proton NMR. Clinical significance Cinobufagin has been shown to have clinical applications in cancer treatment as well as immunomodulatory and analgesic properties. In human adrenocortical cells, cinobufagin inhibits the secretion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentine Toad
''Rhinella arenarum'' is a species of toad in the family Bufonidae that is found in southern Brazil and Uruguay; can also occur in Paraguay. It is also found in Argentina from the Chubut Province northward, Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ... east of the Andes. ''Rhinella arenarum'' inhabits small ponds or bogs with stagnant water, in dry, temperate habitats, mostly in open areas. It is locally common. While it is collected for educational and scientific uses and also suffers from road kills, it in general is not threatened. Fossils representing this species are known with certainty from the late Pliocene up to the Holocene of central Argentina. References arenarum Amphibians described in 1867 Amphibians of Brazil Amphibians of Bolivia Amphibian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
