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Fibrodysplasia Ossificans Progressiva
Fibrodysplasia ossificans progressiva (; FOP), also called Münchmeyer disease or formerly myositis ossificans progressiva, is an extremely rare connective tissue disease in which fibrous connective tissue such as muscle, tendons, and ligaments turn into bone tissue (ossification). It is the only known medical condition in which tissue of one organ system changes into that of another. It is a severe, disabling disorder with no cure. FOP is caused by a mutation of the gene ACVR1. The mutation affects the body's repair mechanism, causing fibrous tissue including muscle, tendons, and ligaments to become ossified, either spontaneously or when damaged as the result of trauma. In many cases, otherwise minor injuries can cause joints to become permanently fused as new bone forms, replacing the damaged muscle tissue. This new bone formation (known as "heterotopic ossification") eventually forms a secondary skeleton and progressively restricts the patient's ability to move. Bone formed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harry Raymond Eastlack
Harry Raymond Eastlack, Jr. (17 November 1933 – 11 November 1973) was the subject of the most recognized case of fibrodysplasia ossificans progressiva (FOP) from the 20th century. His case is also particularly acknowledged, by scientists and researchers, for his contribution to medical advancement. After living with a rare, disabling, and currently incurable genetic disease, Eastlack decided to have his skeleton and medical history donated to the Mütter Museum of the College of Physicians of Philadelphia in support of FOP research. His skeleton is one of the few FOP-presenting, fully articulated ones in existence, and it has proved valuable to the study of the disease. As is characteristic of FOP patients, Eastlack did not demonstrate any possible sign of a disease at birth except for a malformation of the big toes. At the time it was not recognized as the first clinical sign of FOP. It was not until 1937 when the first heterotopic ossification symptom surfaced. By the time of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint
A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw-Hill Connect. Webp.274/ref> They are constructed to allow for different degrees and types of movement. Some joints, such as the knee, elbow, and shoulder, are self-lubricating, almost frictionless, and are able to withstand compression and maintain heavy loads while still executing smooth and precise movements. Other joints such as suture (joint), sutures between the bones of the skull permit very little movement (only during birth) in order to protect the brain and the sense organs. The connection between a tooth and the jawbone is also called a joint, and is described as a fibrous joint known as a gomphosis. Joints are classified both structurally and functionally. Joints play a vital role in the human body, contributing to movement, sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Activin
Activin and inhibin are two closely related protein complexes that have almost directly opposite biological effects. Identified in 1986, activin enhances FSH biosynthesis and secretion, and participates in the regulation of the menstrual cycle. Many other functions have been found to be exerted by activin, including roles in cell proliferation, differentiation, apoptosis, metabolism, homeostasis, immune response, wound repair, and endocrine function. Conversely, inhibin downregulates FSH synthesis and inhibits FSH secretion. The existence of inhibin was hypothesized as early as 1916; however, it was not demonstrated to exist until Neena Schwartz and Cornelia Channing's work in the mid-1970s, after which both proteins were molecularly characterized ten years later. Activin is a dimer composed of two identical or very similar beta subunits. Inhibin is also a dimer wherein the first component is a beta subunit similar or identical to the beta subunit in activin. However, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-zygotic Mutation
A postzygotic mutation (or post-zygotic mutation) is a change in an organism's genome that is acquired during its lifespan, instead of being inherited from its parent(s) through fusion of two haploid gametes. Mutations that occur after the zygote has formed can be caused by a variety of sources that fall under two classes: spontaneous mutations and induced mutations. How detrimental a mutation is to an organism is dependent on what the mutation is, where it occurred in the genome and when it occurred. Causes Postzygotic changes to a genome can be caused by small mutations that affect a single base pair, or large mutations that affect entire chromosomes and are divided into two classes, spontaneous mutations and induced mutations. Spontaneous mutations Most spontaneous mutations are the result of naturally occurring lesions to DNA and errors during DNA replication without direct exposure to an agent. A few common spontaneous mutations are: * Depurination – The loss of a pur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrous Dysplasia
Fibrous dysplasia is a very rare nonhereditary genetic disorder where normal bone and marrow is replaced with fibrous tissue, resulting in formation of bone that is weak and prone to expansion. As a result, most complications result from fracture, deformity, functional impairment, pain, and the impingement of nerves. Disease occurs along a broad clinical spectrum ranging from mostly asymptomatic incidental lesions, to severe disabling disease. Disease can affect one bone ( monostotic), multiple ( polyostotic), or all bones (panostotic) and may occur in isolation or in combination with café au lait skin macules and hyperfunctioning endocrinopathies, termed McCune–Albright syndrome. More rarely, fibrous dysplasia may be associated with intramuscular myxomas, termed Mazabraud's syndrome. Fibrous dysplasia is very rare, and there is no known cure. While fibrous dysplasia is not itself a form of cancer, in severe cases it may undergo a malignant transformation into cancers su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamete
A gamete ( ) is a Ploidy#Haploid and monoploid, haploid cell that fuses with another haploid cell during fertilization in organisms that Sexual reproduction, reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. The name gamete was introduced by the German cytologist Eduard Strasburger in 1878. Gametes of both mating individuals can be the same size and shape, a condition known as isogamy. By contrast, in the majority of species, the gametes are of different sizes, a condition known as anisogamy or heterogamy that applies to humans and other mammals. The human ovum has approximately 100,000 times the volume of a single human sperm cell. The type of gamete an organism produces determines its sex and sets the basis for the sexual roles and sexual selection. In humans and other species that produce two Morphology (biology), morphologically distinct types of gametes, and in which Gonochorism, each individual produces only one type, a femal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penetrance
Penetrance in genetics is the proportion of individuals carrying a particular variant (or allele) of a gene (genotype) that also expresses an associated trait (phenotype). In medical genetics, the penetrance of a disease-causing mutation is the proportion of individuals with the mutation that exhibit clinical Symptom, symptoms among all individuals with such mutation. For example: If a mutation in the gene responsible for a particular autosomal dominant disorder has 95% penetrance, then 95% of those with the mutation will go on to develop the disease, showing its phenotype, whereas 5% will not. Penetrance only refers to whether an individual with a specific genotype exhibits any phenotypic signs or symptoms, and is not to be confused with Expressivity (genetics), variable expressivity which is to what extent or degree the symptoms for said disease are shown (the expression of the phenotypic trait). Meaning that, even if the same disease-causing mutation affects separate individ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expressivity (genetics)
In genetics, expressivity is the degree to which a phenotype is expressed by individuals having a particular genotype. Alternatively, it may refer to the expression of a particular gene by individuals having a certain phenotype. Expressivity is related to the ''intensity'' of a given phenotype; it differs from penetrance, which refers to the ''proportion'' of individuals with a particular genotype that share the same phenotype. Variable expressivity Variable expressivity refers to the phenomenon by which individuals with a shared genotype exhibit varying phenotypes. This can be further described as a spectrum of associated traits that can range in size, colour, intensity, and so forth. Variable expressivity can be seen in plants and animals, such as differences in hair colour, leaf size, and severity of diseases. Mechanisms influencing expressivity This variation in expression can be affected by modifier genes, epigenetic factors or the environment. # Modifier genes can a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominant Gene
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second is called recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance, such as incomp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autosome
An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosomes is collectively known as atDNA or auDNA. For example, humans have a diploid genome that usually contains 22 pairs of autosomes and one allosome pair (46 chromosomes total). The autosome pairs are labeled with numbers (1–22 in humans) roughly in order of their sizes in base pairs, while allosomes are labelled with their letters. By contrast, the allosome pair consists of two X chromosomes in females or one X and one Y chromosome in males. Unusual combinations XYY, XXY, XXX, XXXX, XXXXX or XXYY, among other irregular combinations, are known to occur and usually cause developmental abnormalities. Autosomes still contain sexual determination genes even though they are not sex chromosomes. For example, the SRY gene on the Y chromos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biopsy
A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, an interventional radiologist, or an interventional cardiology, interventional cardiologist. The process involves the extraction of sampling (medicine), sample Cell (biology), cells or Biological tissue, tissues for examination to determine the presence or extent of a disease. The tissue is then Histopathology, fixed, dehydrated, embedded, sectioned, stained and mounted before it is generally examined under a microscope by a pathologist; it may also be analyzed chemically. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. An incisional biopsy or core biopsy samples a portion of the abnormal tissue without attempting to remove the entire lesion or tumor. When a sample of tissue or fluid is removed with a needle in such a way that cells are removed without preserving the histological architecture of the tissue cells, the procedure is called a needle as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physician
A physician, medical practitioner (British English), medical doctor, or simply doctor is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through the Medical education, study, Medical diagnosis, diagnosis, prognosis and therapy, treatment of disease, injury, and other physical and mental impairments. Physicians may focus their practice on certain disease categories, types of patients, and methods of treatment—known as Specialty (medicine), specialities—or they may assume responsibility for the provision of continuing and comprehensive medical care to individuals, families, and communities—known as general practitioner, general practice. Medical practice properly requires both a detailed knowledge of the Discipline (academia), academic disciplines, such as anatomy and physiology, pathophysiology, underlying diseases, and their treatment, which is the science of medicine, and a decent Competence (human resources ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
