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Macrocephaly
Macrocephaly is a condition in which circumference of the human head is abnormally large. It may be pathological or harmless, and can be a Heredity, familial genetic characteristic. People diagnosed with macrocephaly will receive further medical tests to determine whether the syndrome is accompanied by particular Disorder (medicine), disorders. Those with benign or familial macrocephaly are considered to have megalencephaly. Causes Many people with abnormally large heads or large skulls are healthy, but macrocephaly may be pathological. Pathologic macrocephaly may be due to megalencephaly (enlarged brain), hydrocephalus (abnormally increased cerebrospinal fluid), cranial hyperostosis (bone overgrowth), and other conditions. Pathologic macrocephaly is called "syndromic", when it is associated with any other noteworthy condition, and "nonsyndromic" otherwise. Pathologic macrocephaly may be caused by congenital anatomic abnormalities, genetic conditions, or by environmental events. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrocephaly-capillary Malformation
Macrocephaly-capillary malformation (M-CM) is a multiple malformation syndrome causing abnormal body and head overgrowth and cutaneous, Blood vessel, vascular, neurologic, and limb abnormalities. Though not every patient has all features, commonly found signs include macrocephaly, congenital macrosomia, extensive cutaneous capillary malformation (naevus flammeus or port-wine stain type birthmark over much of the body; a capillary malformation of the upper lip or philtrum is seen in many patients with this condition), body asymmetry (also called hemihyperplasia or hemihypertrophy), polydactyly or syndactyly of the hands and feet, lax joints, doughy skin, variable Intellectual disability, developmental delay and other neurologic problems such as seizures and low muscle tone. Genetics Mosaic mutations in PIK3CA have been found to be the genetic cause of M-CM. Other overgrowth conditions with distinct phenotypes have also been found to be caused by mosaic mutations in PIK3CA. How dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalencephaly
Megalencephaly (or macrencephaly; abbreviated MEG) is a growth development disorder in which the brain is abnormally large. It is characterized by a brain with an average weight that is 2.5 standard deviations above the mean of the general population. Approximately 1 out of 50 children (2%) are said to have the characteristics of megalencephaly in the general population. A mutation in the PI3K/AKT/mTOR pathway, PI3K-AKT pathway is believed to be the primary cause of brain proliferation and ultimately the root cause of megalencephaly. This mutation has produced a classification of brain overdevelopment that consists of two syndromes including megalencephaly-capillary malformation (MCAP) and megalencephaly-polydactyly-polymicrogyria-hydrocephalus (MPPH). Megalencephaly is usually diagnosed at birth and is confirmed with an MRI. There are several neuropsychiatric disorders linked with megalencephaly; however, studies have shown that autism is the most prevalent association with the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalencephalic Leukoencephalopathy With Subcortical Cysts
Megalencephalic leukoencephalopathy with subcortical cysts (MLC, or Van der Knaap disease) is a form of hereditary CNS demyelinating disease. It belongs to a group of disorders called leukodystrophies. It is characterized by early-onset enlargement of the head (macrocephaly) as well as delayed-onset neurological deterioration to include spasticity, epilepsy, and lack of muscular coordination. MLC does not appear to be a disease that is fatal at birth or early in life despite its symptoms, although the number of patients throughout history known to have the disease is fairly limited. It belongs to a group of disorders called leukodystrophies. A series of cases with megalencephalic leukodystrophy were described by the Indian neurologist Bhim Sen Singhal (1933-) in 1991. However, it is sometimes referred to as Van der Knaap disease after the Dutch neurologist Marjo van der Knaap who described another series of cases with clinical and radiological features in 1995. There are th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cowden Disease
Cowden syndrome (also known as Cowden's disease) is an autosomal dominant inherited condition characterized by benign overgrowths called hamartomas as well as an increased lifetime risk of breast, thyroid, uterine, and other cancers. It is also known as multiple hamartoma syndrome, a name shared by a more general syndrome of the same name. It is often underdiagnosed due to variability in disease presentation, but 99% of patients report mucocutaneous symptoms by age 20–29. Despite some considering it a primarily dermatologic condition, Cowden's syndrome is a multi-system disorder that also includes neurodevelopmental disorders such as macrocephaly. The incidence of Cowden's disease is about 1 in 200,000, making it quite rare. Furthermore, early and continuous screening is essential in the management of this disorder to prevent malignancies. It is associated with mutations in '' PTEN'' on 10q23.3, a tumor suppressor gene otherwise known as phosphatase and tensin homolog, that re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiofaciocutaneous Syndrome
Cardiofaciocutaneous (CFC) syndrome is an extremely rare genetic disorder, and is one of the RASopathies. It was first described in 1986. It is characterized by the following: *Distinctive facial appearance *Unusually sparse, brittle, curly scalp hair *A range of skin abnormalities from dermatitis to thick, scaly skin over the entire body (generalized ichthyosis) *Heart malformations in over 75% of patients (congenital or appearing later), especially an obstruction of the normal flow of blood from the lower right ventricle of the heart to the lungs (valvar pulmonary stenosis) *Growth delays *Feeding problems associated with severe gastroesophageal reflux disease (GERD) *Foot abnormalities (extra toe or fusion of two or more toes) *Intellectual disability *Failure to thrive Presentation Head Individuals with the disorder usually have distinctive malformations of the craniofacial area including an unusually large head (macrocephaly), prominent forehead, and abnormal narrowing of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weaver Syndrome
Weaver syndrome is an extremely rare autosomal dominant genetic disorder associated with rapid growth beginning in the prenatal period and continuing through the toddler and youth years. It is characterized by advanced osseous maturation and distinctive craniofacial, skeletal and neurological abnormalities. It is similar to Sotos syndrome and is classified as an overgrowth syndrome. Its genetic cause was identified in 2011 as mutations in the ''EZH2'' gene. Forty-eight cases had been documented and confirmed , and its prevalence is estimated to be similar to that of Sotos syndrome, around 1 in 15,000. It was first described by American physician David Weaver in 1974. Signs and symptoms Children with Weaver syndrome tend to look similar and have distinctive physical and craniofacial characteristics, which may include several, but not all, of the following features: * Macrocephaly * Large bifrontal diameter * Flattened occiput * Long philtrum * Retrognathia * Round face in inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sotos Syndrome
Sotos syndrome is a rare genetic disorder characterized by excessive physical growth during the first years of life. Excessive growth often starts in infancy and continues into the early teen years. The disorder may be accompanied by autism, mild intellectual disability, delayed motor, cognitive, and social development, hypotonia (low muscle tone), and speech impairments. Children with Sotos syndrome tend to be large at birth and are often taller, heavier, and have larger skulls (macrocephaly) than is normal for their age. Signs of the disorder, which vary among individuals, include a disproportionately large skull with a slightly protrusive forehead, large hands and feet, large mandible, hypertelorism (an abnormally increased distance between the eyes), and downslanting eyes. Clumsiness, an awkward gait, and unusual aggressiveness or irritability may also occur. Although most cases of Sotos syndrome occur sporadically, familial cases have also been reported. It is similar to Weave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTEN (gene)
Phosphatase and tensin homolog (PTEN) is a phosphatase in humans and is encoded by the ''PTEN'' gene. Mutations of this gene are a step in the development of many cancers, specifically glioblastoma, lung cancer, breast cancer, and prostate cancer. Genes corresponding to PTEN (orthologs) have been identified in most mammals for which complete genome data are available. ''PTEN'' acts as a tumor suppressor gene through the action of its phosphatase protein product. This phosphatase is involved in the regulation of the cell cycle, preventing cells from growing and dividing too rapidly. It is a target of many anticancer drugs. The protein encoded by this gene is a phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase. It contains a tensin-like domain as well as a catalytic domain similar to that of the dual specificity phosphatases. Unlike most of the protein tyrosine phosphatases, this protein preferentially dephosphorylates phosphoinositide substrates. It negatively regul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Disease
Alexander disease is a very rare autosomal dominant leukodystrophy, which are neurological conditions caused by anomalies in the myelin which protects nerve fibers in the brain. The most common type is the infantile form that usually begins during the first two years of life. Symptoms include mental and physical developmental delays, followed by the loss of developmental milestones, an abnormal Macrocephaly, increase in head size and seizures. The juvenile form of Alexander disease has an onset between the ages of 2 and 13 years. These children may have excessive vomiting, difficulty swallowing and speaking, poor coordination, and loss of motor control. Adult-onset forms of Alexander disease are less common. The symptoms sometimes mimic those of Parkinson's disease or multiple sclerosis, or may present primarily as a psychiatric disorder. According to the National Institute of Neurological Disorders and Stroke, the destruction of white matter is accompanied by the formation of Ros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Head
In human anatomy, the head is at the top of the human body. It supports the face and is maintained by the human skull, skull, which itself encloses the human brain, brain. Structure The human head consists of a fleshy outer portion, which surrounds the bony human skull, skull. The brain is enclosed within the skull. There are 22 bones in the human head. The head rests on the neck, and the seven cervical vertebrae support it. The human head typically weighs between Over 98% of humans fit into this range. There have been odd incidences where human beings have abnormally small or large heads. The Zika virus was responsible for underdeveloped heads in the early 2000s. The face is the anterior part of the head, containing the Human eye, eyes, Human nose, nose, and Human mouth, mouth. On either side of the mouth, the cheeks provide a fleshy border to the Human mouth, oral cavity. The ears sit to either side of the head. Blood supply The head receives blood supply through the in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocephalus
Hydrocephalus is a condition in which cerebrospinal fluid (CSF) builds up within the brain, which can cause pressure to increase in the skull. Symptoms may vary according to age. Headaches and double vision are common. Elderly adults with normal pressure hydrocephalus (NPH) may have poor balance, difficulty controlling urination, or mental impairment. In babies, there may be a rapid increase in head size. Other symptoms may include vomiting, sleepiness, seizures, and downward pointing of the eyes. Hydrocephalus can occur due to birth defects (primary) or can develop later in life (secondary). Hydrocephalus can be classified via mechanism into communicating, noncommunicating, ''ex vacuo'', and normal pressure hydrocephalus. Diagnosis is made by physical examination and medical imaging, such as a CT scan. Hydrocephalus is typically treated through surgery. One option is the placement of a shunt system. A procedure called an endoscopic third ventriculostomy has gained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
