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Winchester Syndrome
Winchester syndrome is a rare hereditary connective tissue disease described in 1969, of which the main characteristics are short stature, marked contractures of joints, opacities in the cornea, coarse facial features, dissolution of the carpal and tarsal bones (in the hands and feet, respectively), and osteoporosis. Winchester syndrome was once considered to be related to a similar condition, multicentric osteolysis, nodulosis, and arthropathy (MONA). However, it was discovered that the two are caused by mutations found in different genes; however they mostly produce the same phenotype or clinical picture. Appearances resemble rheumatoid arthritis. Increased uronic acid is demonstrated in cultured fibroblasts from the skin and to a lesser degree in both parents. Despite initial tests not showing increased mucopolysaccharide excretion, the disease was regarded as a mucopolysaccharidosis. Winchester syndrome is thought to be inherited as an autosomal recessive trait. Sympto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MMP2
72 kDa type IV collagenase also known as matrix metalloproteinase-2 (MMP-2) and gelatinase A is an enzyme that in humans is encoded by the ''MMP2'' gene. The ''MMP2'' gene is located on chromosome 16 at position 12.2. Function Proteins of the matrix metalloproteinase (MMP) family are involved in the breakdown of extracellular matrix (ECM) in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes, such as arthritis and metastasis. Most MMP's are secreted as inactive proproteins which are activated when cleaved by extracellular proteinases. This gene encodes an enzyme which degrades type IV collagen, the major structural component of basement membranes. The enzyme plays a role in endometrial menstrual breakdown, regulation of vascularization and the inflammatory response. Activation Activation of MMP-2 requires proteolytic processing. A complex of membrane type 1 MMP (MT1-MMP/MMP14) and tissue inhibit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteopenia
Osteopenia, known as "low bone mass" or "low bone density", is a condition in which bone mineral density is low. Because their bones are weaker, people with osteopenia may have a higher risk of fractures, and some people may go on to develop osteoporosis. In 2010, 43 million older adults in the US had osteopenia. Unlike osteoporosis, osteopenia does not usually cause symptoms, and losing bone density in itself does not cause pain. There is no single cause for osteopenia, although there are several risk factors, including modifiable (behavioral, including dietary and use of certain drugs) and non-modifiable (for instance, loss of bone mass with age). For people with risk factors, screening via a DXA scanner may help to detect the development and progression of low bone density. Prevention of low bone density may begin early in life and includes a healthy diet and weight-bearing exercise, as well as avoidance of tobacco and alcohol. The treatment of osteopenia is controversial: non-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Disorders
A metabolic disorder is a disorder that negatively alters the body's processing and distribution of macronutrients, such as Protein, proteins, Fat, fats, and Carbohydrate, carbohydrates. Metabolic disorders can happen when abnormal chemical reactions in the body alter the normal metabolic process. It can also be defined as inherited single gene anomaly, most of which are Dominance (genetics), autosomal recessive. Signs and symptoms Some of the symptoms that can occur with metabolic disorders are lethargy, weight loss, jaundice and seizures. The symptoms expressed would vary with the type of metabolic disorder. There are four categories of symptoms: acute symptoms, late-onset acute symptoms, progressive general symptoms and permanent symptoms. Causes Inherited metabolic disorders are one cause of metabolic disorders, and occur when a defective gene causes an enzyme deficiency. These diseases, of which there are many subtypes, are known as inborn errors of metabolism. Metabolic d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inborn Errors Of Metabolism
Inborn errors of metabolism form a large class of genetic diseases involving congenital disorders of enzyme activities. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances ( substrates) into others (products). In most of the disorders, problems arise due to accumulation of substances which are toxic or interfere with normal function, or due to the effects of reduced ability to synthesize essential compounds. Inborn errors of metabolism are now often referred to as congenital metabolic diseases or inherited metabolic disorders. To this concept it's possible to include the new term of Enzymopathy. This term was created following the study of Biodynamic Enzymology, a science based on the study of the enzymes and their derivated products. Finally, ''inborn errors of metabolism'' were studied for the first time by British physician Archibald Garrod (1857–1936), in 1908. He is known for work that prefigured the "one gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicentric Carpotarsal Osteolysis Syndrome
Multicentric carpotarsal osteolysis syndrome (MCTO) is a rare autosomal dominant condition.Shurtleff DB, Sparkes RS, Clawson DK, Guntheroth WG, Mottet NK (1964) Hereditary osteolysis with hypertension and nephropathy. JAMA 188:363–368 This condition is also known as idiopathic multicentric osteolysis with nephropathy. It is characterised by carpal- tarsal destruction and kidney failure. Signs and symptoms The presentation is of gradual loss of the small bones in the carpus and tarsus. This may lead to joint subluxation and instability. The kidney failure, when present, usually presents as the presence of protein in the urine. In some cases, there may also be craniofacial abnormalities including * Triangular facies * Micrognathia * Maxillary hypoplasia * Exophthalmos Histology of renal biopsies show glomerulosclerosis and severe tubulointerstitial fibrosis. Intellectual disability may occur. Genetics This condition is caused by mutations in the transcription factor MafB, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication (translesion synthesis). Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from CT and PET scans. MRI is a medical application of nuclear magnetic resonance (NMR) which can also be used for imaging in other NMR applications, such as NMR spectroscopy. MRI is widely used in hospitals and clinics for medical diagnosis, staging and follow-up of disease. Compared to CT, MRI provides better contrast in images of soft-tissues, e.g. in the brain or abdomen. However, it may be perceived as less comfortable by patients, due to the usually longer and louder measurements with the subject in a long, confining tube, though "Open" MRI designs mostly relieve this. Additionally, implants and oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz ( to ) and energies in the range 145 eV to 124 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it on November 8, 1895. He named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . Spellings of ''X-ray(s)'' in English include the variants ''x-ray(s)'', ''xray(s)'', and ''X ray(s)''. The most familiar use of X-rays is checking for fractures (broken bones), but X-rays are also used in other ways. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperpigmentation
Hyperpigmentation is the darkening of an area of skin or nails caused by increased melanin. Causes Hyperpigmentation can be caused by sun damage, inflammation, or other skin injuries, including those related to acne vulgaris.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . People with darker skin tones are more prone to hyperpigmentation, especially with excess sun exposure. Many forms of hyperpigmentation are caused by an excess production of melanin. Hyperpigmentation can be diffuse or focal, affecting such areas as the face and the back of the hands. Melanin is produced by melanocytes at the lower layer of the epidermis. Melanin is a class of pigment responsible for producing color in the body in places such as the eyes, skin, and hair. The process of melanin synthesis (melanogenesis) starts with the oxidation of -tyrosine to by the enzyme tyrosine hydroxylase, then to -dopaquinone and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type I Collagen
Type I collagen is the most abundant collagen of the human body. It forms large, eosinophilic fibers known as collagen fibers. It is present in scar tissue, the end product when tissue heals by repair, as well as tendons, ligaments, the endomysium of myofibrils, the organic part of bone, the dermis, the dentin, and organ capsules. Formation The gene produces the pro-alpha1(I) chain. This chain combines with another pro-alpha1(I) chain and also with a pro-alpha2(I) chain (produced by the gene) to make a molecule of type I pro-collagen. These triple-stranded, rope-like pro-collagen molecules must be processed by enzymes outside the cell. Once these molecules are processed, they arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-links result in the formation of very strong mature type I collagen fiber. Clinical significance See Collagen, type I, alpha 1#Clinical significance Markers used to measure bone loss are not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrix Metalloproteinase 2
Gelatinase A, also known as MMP2 (, ''72-kDa gelatinase'', ''matrix metalloproteinase 2'', ''type IV collagenase'', ''3/4 collagenase'', ''matrix metalloproteinase 5'', ''72 kDa gelatinase type A'', ''collagenase IV'', ''collagenase type IV'', ''MMP 2'', ''type IV collagen metalloproteinase'', ''type IV collagenase/gelatinase'') is an enzyme. This enzyme catalyses the following chemical reaction : Cleavage of gelatin type I and collagen types IV, V, VII, X. Cleaves the collagen-like sequence Pro-Gln-Gly-Ile-Ala-Gly-Gln This secreted endopeptidase belongs to the peptidase A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the fo ... family M10. References External links * {{Portal bar, Biology, border=no EC 3.4.24 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
