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Marfanoid Habitus
Marfanoid (or Marfanoid habitus) is a constellation of signs resembling those of Marfan syndrome, including long limbs, with an arm span that is at least 1.03 of the height of the individual, and a crowded oral maxilla, sometimes with a high arch in the palate, arachnodactyly, and hyperlaxity. __TOC__ Signs and symptoms Arachnodactyly (long fingers), long limbs, scoliosis (curved spine), a hidden feature of bony lip growth towards vestibular aqueduct (which can be seen in CT scan reports), and imprecise articulation of speech due to high-arched palate are all considered Marfanoid symptoms. Language and cognition can be affected in neonatal Marfan syndrome where intellectual disability exists. Hearing may be impaired, either by conductive loss due to hypermobility of ossicles, by inflamed tympanic membrane, or sensorineurally through the vestibular aqueduct. In cases with hearing impairment, giddiness and imbalance may co-occur. Other symptoms include crowding of teeth and long or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marfan Syndrome
Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with dolichostenomelia, long arms, legs, Arachnodactyly, fingers, and toes. They also typically have hypermobility (joints), exceptionally flexible joints and scoliosis, abnormally curved spines. The most serious complications involve the heart and aorta, with an increased risk of mitral valve prolapse and aortic aneurysm. The lungs, eyes, bones, and the dura mater, covering of the spinal cord are also commonly affected. The severity of the symptoms is variable. MFS is caused by a mutation in ''FBN1'', one of the genes that make fibrillin, which results in abnormal connective tissue. It is an autosomal dominant disorder. In about 75% of cases, it is inherited from a parent with the condition, while in about 25% it is a new mutation. Diagnosis is often based on the Ghent criteria, family history and genetic testing (DNA analysis). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibular Aqueduct
At the posterior lateral wall of the temporal bone is the vestibular aqueduct, which extends to the posterior surface of the petrous portion of the temporal bone. The vestibular aqueduct parallels the petrous apex, in contrast to the cochlear aqueduct, which lies perpendicular to the petrous apex. It transmits a small vein, and contains a tubular prolongation of the membranous labyrinth, the ductus endolymphaticus, which ends in a cul-de-sac, the endolymphatic sac, between the layers of the dura mater within the cranial cavity. Pathology Enlargement of the vestibular aqueduct to greater than 2 mm is associated with enlarged vestibular aqueduct syndrome, a disease entity that is associated with one-sided hearing loss in children. The diagnosis can be made by high resolution CT or MRI, with comparison to the adjacent posterior semicircular canal The semicircular canals are three semicircular interconnected tubes located in the innermost part of each ear, the inne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perrault Syndrome
XX gonadal dysgenesis is a type of female hypogonadism in which the ovaries do not function to induce puberty in a person assigned female at birth, whose karyotype is 46,XX. Individuals with XX gonadal dysgenesis have normal-appearing external genitalia as well as Müllerian structures (e.g., cervix, vagina, uterus). Due to the nearly absent or nonfunctional streak ovaries (under-developed ovaries that are then small and fibrous tissue, hence the term "streak"), the individual is low in estrogen levels ( hypoestrogenic) and has high levels of follicle-stimulating hormone ( FSH) and luteinizing hormone ( LH), hormones that cycle in the reproductive system. As a result, the diagnosis often occurs after a concern for delayed puberty or amenorrhea. Treatment generally involves hormone replacement therapy with estrogen and progesterone. Presentation Signs and Symptoms Individuals with XX gonadal dysgenesis appear phenotypical female with normal internal and external genitalia, bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SMS (gene)
Spermine synthase is an enzyme that in humans is encoded by the ''SMS'' gene. The protein encoded by this gene belongs to the spermidine/spermine synthases family. This gene encodes a ubiquitous enzyme of polyamine A polyamine is an organic compound having two or more amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. ... metabolism. References Further reading * * * * * * * * * {{refend Genes mutated in mice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snyder–Robinson Syndrome
Snyder–Robinson syndrome (SRS) is an extremely rare inherited genetic disorder characterized by muscular and skeletal abnormalities, varying degrees of intellectual disability, seizures, and slow development. SRS is caused by a mutated ''SMS'' gene at chromosome Xp21.3-p22.12, which carries instructions for producing the enzyme spermine synthase. Spermine synthase in turn helps the body produce spermine, a polyamine critical to cell processes such as cell division, tissue repair, and apoptosis. The resulting shortage of spermine in cells causes problems with development and brain function, though the exact mechanism is not understood. The syndrome has also been referred to as Snyder–Robinson X-linked mental retardation syndrome (MRXSSR) and spermine synthase deficiency. SRS exclusively affects males. Only about ten families currently have a child with SRS, and 50 people have been diagnosed worldwide since 1969. Presentation Snyder–Robinson usually is noticeable in infants, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocystinuria
Homocystinuria (HCU) is an inherited disorder of the metabolism of the amino acid methionine due to a deficiency of cystathionine beta synthase or methionine synthase. It is an inherited autosomal recessive trait, which means a child needs to inherit a copy of the defective gene from both parents to be affected. Symptoms of homocystinuria can also be caused by a deficiency of vitamins B6, B12, or folate. Signs and symptoms This defect leads to a multi-systemic disorder of the connective tissue, muscles, central nervous system (CNS), and cardiovascular system. Homocystinuria represents a group of hereditary metabolic disorders characterized by an accumulation of the amino acid homocysteine in the serum and an increased excretion of homocysteine in the urine. Infants appear to be normal and early symptoms, if any are present, are vague. Signs and symptoms of homocystinuria that may be seen include the following: Cause It is usually caused by the deficiency of the enzyme cyst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tympanic Membrane
In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear from the middle ear. Its function is to transmit changes in pressure of sound from the air to the ossicles inside the middle ear, and thence to the oval window in the fluid-filled cochlea. The ear thereby converts and amplifies vibration in the air to vibration in cochlear fluid. The malleus bone bridges the gap between the eardrum and the other ossicles. Rupture or perforation of the eardrum can lead to conductive hearing loss. Collapse or retraction of the eardrum can cause conductive hearing loss or cholesteatoma. Structure Orientation and relations The tympanic membrane is oriented obliquely in the anteroposterior, mediolateral, and superoinferior planes. Consequently, its superoposterior end lies lateral to its anteroinferior end. Anatomically, it relates superiorly to the middle cranial fos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnodactyly
Arachnodactyly ("spider fingers") is a medical condition that is characterized by fingers and toes that are abnormally long and slender, in comparison to the palm of the hand and arch of the foot. In some cases, the thumbs of an individual with the condition are pulled inwards towards the palm. This condition is present at birth. Causes This feature can occur on its own with no underlying health problems, or it can be associated with certain medical conditions, including Marfan syndrome, Ehlers–Danlos syndromes, Loeys–Dietz syndrome, and homocystinuria. It is also seen in congenital contractural arachnodactyly, which is caused by mutation in the gene encoding fibrillin-2 on chromosome 5q23. Notable cases It remains unconfirmed whether composer Sergei Rachmaninoff's abnormally large reach on a piano was a result of arachnodactyly due to Marfan syndrome Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the conditio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ossicles
The ossicles (also called auditory ossicles) are three irregular bones in the middle ear of humans and other mammals, and are among the smallest bones in the human body. Although the term "ossicle" literally means "tiny bone" (from Latin ''ossiculum'') and may refer to any small bone throughout the body, it typically refers specifically to the malleus, incus and stapes ("hammer, anvil, and stirrup") of the middle ear. The auditory ossicles serve as a kinematic chain to transmit and amplify ( intensify) sound vibrations collected from the air by the ear drum to the fluid-filled labyrinth ( cochlea). The absence or pathology of the auditory ossicles would constitute a moderate-to-severe conductive hearing loss. Structure The ossicles are, in order from the eardrum to the inner ear (from superficial to deep): the malleus, incus, and stapes, terms that in Latin are translated as "the hammer, anvil, and stirrup". * The malleus () articulates with the incus through the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-arched Palate
A high-arched palate (also termed high-vaulted palate) is where the palate is unusually high and narrow. It is usually a congenital developmental feature that results from the failure of the palatal shelves to fuse correctly in development, the same phenomenon that leads to cleft palate. It may occur in isolation or in association with a number of conditions. It may also be an acquired condition caused by chronic thumb-sucking. A high-arched palate may result in a narrowed airway and sleep disordered breathing. Examples of conditions which may be associated with a high-arched palate include: * Allergic rhinitis * Apert syndrome * Crouzon syndrome * Down syndrome * Ehlers-Danlos Syndrome * Friedreich's ataxia * Fragile X syndrome * Incontinentia pigmenti * Marfan syndrome * Sotos syndrome * Treacher Collins syndrome * Upper Airway Resistance Syndrome See also * Minor physical anomalies * Bardet–Biedl syndrome Bardet–Biedl syndrome (BBS) is a ciliopathic human genetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
