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Glycocholic Acid
Glycocholic acid, or cholylglycine, is a crystalline bile acid involved in the emulsification of fats. It occurs as a sodium salt in the bile of mammals. It is a conjugate of cholic acid with glycine. Its anion is called glycocholate. In a prospective study, positive associations were observed between prediagnostic plasma levels of seven conjugated bile acid metabolites, including glycocholic acid, and colon cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel ... risk. These findings support experimental data suggesting that high circulating bile acids promote colon cancer risk. See also * Taurocholic acid References Bile acids Cholanes {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bile Acid
Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver in peroxisomes. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts. Primary bile acids are those synthesized by the liver. Secondary bile acids result from bacterial actions in the colon. In humans, taurocholic acid and glycocholic acid (derivatives of cholic acid) and taurochenodeoxycholic acid and glycochenodeoxycholic acid (derivatives of chenodeoxycholic acid) are the major bile salts. The salts of their 7-alpha-dehydroxylated derivatives, deoxycholic acid and lithocholic acid, are also found, with derivatives of cholic, chenodeoxycholic and deoxycholic acids accounting for over 90% of human biliary bile acids. Description Bile acids comprise about 80% of the organic compounds in bile (others are phospholipids and cholesterol). An increased secretion of bile acids produces an increase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emulsification
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms ''colloid'' and ''emulsion'' are sometimes used interchangeably, ''emulsion'' should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase). Examples of emulsions include vinaigrettes, homogenized milk, liquid biomolecular condensates, and some cutting fluids for metal working. Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which the oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are also p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions ( cations) and negatively charged ions ( anions), which results in a compound with no net electric charge (electrically neutral). The constituent ions are held together by electrostatic forces termed ionic bonds. The component ions in a salt can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as sodium (Na+) and chloride (Cl−) in sodium chloride, or polyatomic, such as ammonium () and carbonate () ions in ammonium carbonate. Salts containing basic ions hydroxide (OH−) or oxide (O2−) are classified as bases, such as sodium hydroxide and potassium oxide. Individual ions within a salt usually have multiple near neighbours, so they are not considered to be part of molecules, but instead part of a continuous three-dimensional network. Salts usually form crystalline structures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bile
Bile (from Latin ''bilis''), also known as gall, is a yellow-green/misty green fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is primarily composed of water, is produced continuously by the liver, and is stored and concentrated in the gallbladder. After a human eats, this stored bile is discharged into the first section of the small intestine, known as the duodenum. Composition In the human liver, bile is composed of 97–98% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats ( cholesterol, fatty acids, and lecithin), and 200 meq/L inorganic salts. The two main pigments of bile are bilirubin, which is orange-yellow, and its oxidised form biliverdin, which is green. When mixed, they are responsible for the brown color of feces. About of bile is produced per day in adult human beings. Function Bile or gall acts to some extent as a surfactant, helping to emulsify the lipids in food. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three Evolution of mammalian auditory ossicles, middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors Genetic divergence, diverged in the Carboniferous Period over 300 million years ago. Around 6,640 Neontology#Extant taxon, extant species of mammals have been described and divided into 27 Order (biology), orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, Mole (animal), moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the Artiodactyl, even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including Felidae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjugated System
In physical organic chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in a molecule, which in general lowers the overall energy of the molecule and increases Chemical stability, stability. It is Resonance (chemistry), conventionally represented as having alternating single and multiple covalent bond, bonds. Lone pairs, radical (chemistry), radicals or carbenium ions may be part of the system, which may be Cyclic molecule, cyclic, acyclic, Linear molecular geometry, linear or mixed. The term "conjugated" was coined in 1899 by the German chemist Johannes Thiele (chemist), Johannes Thiele. Conjugation is the orbital overlap, overlap of one p-orbital with another across an adjacent Sigma bond, σ bond (in transition metals, d-orbitals can be involved). A conjugated system has a region of overlapping p-orbitals, bridging the interjacent locations that simple diagrams illustrate as not having a π bond. They allow a delocalization of pi el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholic Acid
Cholic acid, also known as 3α,7α,12α-trihydroxy-5β-cholan-24-oic acid is a primary bile acid that is insoluble in water (soluble in alcohol and acetic acid), it is a white crystalline substance. Salts of cholic acid are called cholates. Cholic acid, along with chenodeoxycholic acid, is one of the two major bile acids produced by the liver, where it is synthesized from cholesterol. These two major bile acids are roughly equal in concentration in humans. Derivatives are made from cholyl-CoA, which exchanges its CoA with either glycine, or taurine, yielding glycocholic and taurocholic acid, respectively. Cholic acid downregulates cholesterol-7-α-hydroxylase (rate-limiting step in bile acid synthesis), and cholesterol does the opposite. This is why chenodeoxycholic acid, and not cholic acid, can be used to treat gallstones (because decreasing bile acid synthesis would supersaturate the stones even more). Cholic acid and chenodeoxycholic acid are the most important huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine disrupts the formation of alpha-helices in secondary protein structure. Its small side chain causes it to favor random coils instead. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a '' Clostridium tetani'' infection) can cause spastic paralysis due to uninhibited muscle contraction. It is the only achiral proteinogenic amino acid. It can fit into both hydrophilic and hydrophobic environments, due to its minimal side chain of only one hydrogen atom. History and etymology Glycine was discovered in 1820 by French chemist Henri Braconnot when he hydrolyzed gelatin by boiling it with sulfuric acid. He originally called it "sugar of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MeSH
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorectal Cancer
Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the Colon (anatomy), colon or rectum (parts of the large intestine). Signs and symptoms may include Lower gastrointestinal bleeding, blood in the stool, a change in bowel movements, weight loss, abdominal pain and fatigue. Most colorectal cancers are due to lifestyle factors and genetic disorders. Risk factors include diet, obesity, smoking, and lack of physical activity. Dietary factors that increase the risk include red meat, processed meat, and alcohol (drug), alcohol. Another risk factor is inflammatory bowel disease, which includes Crohn's disease and ulcerative colitis. Some of the inherited genetic disorders that can cause colorectal cancer include familial adenomatous polyposis and hereditary non-polyposis colon cancer; however, these represent less than 5% of cases. It typically starts as a adenoma, benign tumor, often in the form of a colorectal poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taurocholic Acid
Taurocholic acid, known also as cholaic acid, cholyltaurine, or acidum cholatauricum, is a deliquescent yellowish crystalline bile acid involved in the emulsification of fats. It occurs as a sodium salt in the bile of mammals. It is a conjugate of cholic acid with taurine. In medical use, it is administered as a cholagogue and choleretic. Hydrolysis of taurocholic acid yields taurine. For commercial use, taurocholic acid is manufactured from cattle bile, a byproduct of the meat-processing industry. This acid is also one of the many molecules in the body that has cholesterol as its precursor. In a large prospective study (involving 569 incident colon cancer cases and 569 matched controls) it was found that prediagnostic concentrations of circulating taurocholic acid, as well as six other bile acids, were statistically significantly associated with increased colon cancer risk. Toxicity The median lethal dose In toxicology, the median lethal dose, LD50 (abbreviation for " l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bile Acids
Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver in peroxisomes. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts. Primary bile acids are those synthesized by the liver. Secondary bile acids result from bacterial actions in the colon (anatomy), colon. In humans, taurocholic acid and glycocholic acid (derivatives of cholic acid) and taurochenodeoxycholic acid and glycochenodeoxycholic acid (derivatives of chenodeoxycholic acid) are the major bile salts. The salts of their 7-alpha-dehydroxylated derivatives, deoxycholic acid and lithocholic acid, are also found, with derivatives of cholic, chenodeoxycholic and deoxycholic acids accounting for over 90% of human biliary bile acids. Description Bile acids comprise about 80% of the organic compounds in bile (others are phospholipids and cholesterol). An increased secretion of bile acids produces an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
