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Allan–Herndon–Dudley Syndrome
Allan–Herndon–Dudley syndrome is a rare X-linked inherited disorder of brain development that causes both moderate to severe intellectual disability and problems with speech and movement. Allan–Herndon–Dudley syndrome, which is named eponymously for William Allan, Florence C. Dudley, and C. Nash Herndon, results from a mutation of the thyroid hormone transporter MCT8 (also referred to as SLC16A2). Consequently, thyroid hormones are unable to enter the nervous system, which depends on thyroid signaling for proper function and development. Signs and symptoms It is estimated that 80–99% of people with Allan–Herndon–Dudley syndrome will have biparietal narrowing (narrowing of skull), ataxia, abnormalities of the neck, and both absent speech development and aphasia. Weak muscle tone (hypotonia) and underdevelopment of many muscles ( muscle hypoplasia) are common in children with Allan–Herndon–Dudley syndrome. Development of joint deformities called contractures, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons typically communicate with one another by means of long fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. Physiologically, brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. This centralized control allows rapid and coordinated respon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Cell
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon and dendrite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Transport Protein Disorders
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. Biological membranes include cell membranes (outer coverings of cells or organelles that allow passage of certain constituents); nuclear membranes, which cover a cell nucleus; and tissue membranes, such as mucosae and serosae. Synthetic membranes are made by humans for use in laboratories and industry (such as chemical plants). This concept of a membrane has been known since the eighteenth century but was used little outside of the laboratory until the end of World War II. Drinking water supplies in Europe had been compromised by the war and membrane filters were used to test for water safety. However, due to the lack of reliability, slow operation, reduced selectivity and elevated costs, membranes were not widely exploited. The first use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santiago De Compostela
Santiago de Compostela is the capital of the autonomous community of Galicia, in northwestern Spain. The city has its origin in the shrine of Saint James the Great, now the Cathedral of Santiago de Compostela, as the destination of the Way of St. James, a leading Catholic pilgrimage route since the 9th century. In 1985, the city's Old Town was designated a UNESCO World Heritage Site. Santiago de Compostela has a very mild climate for its latitude with heavy winter rainfall courtesy of its relative proximity to the prevailing winds from Atlantic low-pressure systems. Toponym ''Santiago'' is the local Galician evolution of Vulgar Latin ''Sanctus Iacobus'' " Saint James". According to legend, ''Compostela'' derives from the Latin ''Campus Stellae'' (i.e., "field of the star"); it seems unlikely, however, that this phrase could have yielded the modern ''Compostela'' under normal evolution from Latin to Medieval Galician. Other etymologies derive the name from Latin ''compositum'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiratricol
Tiratricol (also known as TRIAC or triiodothyroacetic acid) is a thyroid hormone analogue. Triiodothyroacetic acid is also a physiologic thyroid hormone that is present in the normal organism in low concentrations. Uses It is indicated in the management of thyroid hormone resistance syndrome and is used, in combination with levothyroxine, to suppress thyroid-stimulating hormone production in patients with thyroid cancer. It has been investigated for use in reducing goiter. It has also shown some effectiveness in reducing the atrophy caused when using corticosteroids. Tiratricol has also been widely marketed, under various trade names, as a weight loss aid. In 1999 and 2000, the United States Food and Drug Administration and Health Canada both issued warnings to the public regarding the use of dietary supplements containing tiratricol. Legal status Tiratricol is not approved for sale in Canada or the United States. It was once an approved drug in Brazil Brazil ( p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid Disease
Thyroid disease is a medical condition that affects the function of the thyroid gland. The thyroid gland is located at the front of the neck and produces thyroid hormones that travel through the blood to help regulate many other organs, meaning that it is an endocrine organ. These hormones normally act in the body to regulate energy use, infant development, and childhood development. There are five general types of thyroid disease, each with their own symptoms. A person may have one or several different types at the same time. The five groups are: # Hypothyroidism (low function) caused by not having enough free thyroid hormones # Hyperthyroidism (high function) caused by having too many free thyroid hormones # Structural abnormalities, most commonly a goiter (enlargement of the thyroid gland) # Tumors which can be benign (not cancerous) or cancerous # Abnormal thyroid function tests without any clinical symptoms (subclinical hypothyroidism or subclinical hyperthyroidism). In som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silychristin
Silychristin (also known as silichristin) is a natural product and one of the constituents of silymarin, the standardized, active extract of the fruit of milk thistle, ''Silybum marianum''. It is the second most abundant constituent in silymarin, after silybin.Biedermann, D.; Buchta, M.; Holečková, V.; Sedlák, D.; Valentová, K.; Cvačka, J.; Bednárová, L.; Křenková, A.; Kuzma, M.; Škuta, C.; Peikerová, Ž.; Bartůněk, P.; Křen, V., Silychristin: Skeletal Alterations and Biological Activities. ''Journal of Natural Products'' 2016, 79 (12), 3086–3092. Silychristin is a flavonolignan, along with many other silymarin constituents (such as silybin, isosilybin, silydianin, etc.), meaning it is composed up of a flavonoid and a lignan. It is estimated that up to 65–80% of silymarin extract is made up of flavonolignans, like silychristin, which give silymarin its well known potent antioxidant and hepatoprotective properties. Silychristin can exist as two stereois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid Hormones
File:Thyroid_system.svg, upright=1.5, The thyroid system of the thyroid hormones T3 and T4 rect 376 268 820 433 Thyroid-stimulating hormone rect 411 200 849 266 Thyrotropin-releasing hormone rect 297 168 502 200 Hypothalamus rect 66 216 386 256 Anterior pituitary gland rect 66 332 342 374 Negative feedback rect 308 436 510 475 Thyroid gland rect 256 539 563 635 Thyroid hormones rect 357 827 569 856 Catecholamine rect 399 716 591 750 Metabolism desc bottom-left Thyroid hormones are any hormones produced and released by the thyroid gland, namely triiodothyronine (T3) and thyroxine (T4). They are tyrosine-based hormones that are primarily responsible for regulation of metabolism. T3 and T4 are partially composed of iodine. A deficiency of iodine leads to decreased production of T3 and T4, enlarges the thyroid tissue and will cause the disease known as simple goitre. The major form of thyroid hormone in the blood is thyroxine (T4), whose half-life of around one week is longer th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavonolignan
Flavonolignans are natural phenols composed of a part flavonoid and a part phenylpropane. Examples Flavonolignans identified in ''Silybum marianum'' (milk thistle) silymarin complex include silibinin, silychristin, silydianin, dehydrosilybin, deoxysilycistin, deoxysilydianin, silandrin, silybinome, silyhermin and neosilyhermin and can be produced in vitro. Silibinin is found in the roots of S. marianum while silyamandin can be found in the fruit. Hydnocarpin can be found naturally in '' Onopordon corymbosum'' and can be synthesised. Scutellaprostin A, B, C, D, E and F can be isolated from '' Scutellaria prostrata'' and can also be synthesized. Hydnowightin can be isolated from '' Hydnocarpus wightiana'' seeds. Three flavonolignans derived from the flavone tricin have been isolated from the herb ''Avena sativa''. Palstatin has been isolated from the Amazon tree '' Hymeneae palustris''. Salcolin A and salcolin B can be found in '' Salsola collina''. Rhodiol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocarboxylate Transporter 8
Monocarboxylate transporter 8 (MCT8) is an active transporter protein that in humans is encoded by the ''SLC16A2'' gene. Function MCT8 actively transports a variety of iodo- thyronines including the thyroid hormones T3 and T4. Clinical significance A genetic disorder (discovered in 2003 and 2004) is caused by mutation in the transporter of thyroid hormone, MCT8, also known as SLC16A2, is believed to be account for a significant fraction of the undiagnosed neurological disorders (usually resulting in hypotonic/floppy infants with delayed milestones). This genetic defect was known as Allan–Herndon–Dudley syndrome (since 1944) without knowing its actual cause. It has been shown mutated in cases of X-linked leukoencephalopathy. Some of the symptoms for this disorder as are follows: normal to slightly elevated TSH, elevated T3 and reduced T4 (ratio of T3/T4 is about double its normal value). Normal looking at birth and for the first few years, hypotonic (floppy), in partic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silymarin
Silibinin (International Nonproprietary Name, INN), also known as silybin (both from ''Silybum'', the Genus–differentia definition, generic name of the plant from which it is extracted), is the major active constituent of silymarin, a standardized extract of the Silybum marianum, milk thistle seeds, containing a mixture of flavonolignans consisting of silibinin, isosilibinin, silychristin, silidianin, and others. Silibinin itself is a mixture of two diastereomers, silybin A and silybin B, in approximately equimolar ratio. The mixture exhibits a number of pharmacological effects, particularly in the fatty liver, non-alcoholic fatty liver, non-alcoholic steatohepatitis, and there is great clinical evidence for the use of silibinin as a supportive element in Alcoholic liver cirrhosis, alcoholic and Child–Pugh score, Child–Pugh grade 'A' liver cirrhosis. However, despite its several beneficial effects on the liver, silibinin and all the other compounds found in silymarin, espe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapses
In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. Synapses are essential to the transmission of nervous impulses from one neuron to another. Neurons are specialized to pass signals to individual target cells, and synapses are the means by which they do so. At a synapse, the plasma membrane of the signal-passing neuron (the ''presynaptic'' neuron) comes into close apposition with the membrane of the target (''postsynaptic'') cell. Both the presynaptic and postsynaptic sites contain extensive arrays of molecular machinery that link the two membranes together and carry out the signaling process. In many synapses, the presynaptic part is located on an axon and the postsynaptic part is located on a dendrite or soma. Astrocytes also exchange information with the synaptic neurons, responding to synaptic activity and, in turn, regulating neurotransmission. Syna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
