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Neurofibromatosis–Noonan Syndrome
Watson syndrome is a rare genetic condition characterised by café-au-lait patches of skin, short stature, pulmonary stenosis, developmental delays, and learning difficulties. Its inheritance is autosomal dominant, and it may also occur with Lisch nodules of the ocular iris, axillary/inguinal freckling, and neurofibromas. Watson syndrome is caused by mutations in the ''NF1'' gene, the same gene associated with neurofibromatosis type 1. It is believed that Watson syndrome and neurofibromatosis-1 result from allelic mutations at the ''NF1'' locus''.'' Watson syndrome has sometimes been described as a 'milder form' of neurofibromatosis-1 due to shared features including mutation of the ''NF1'' gene, café-au-lait patches, and neurofibroma, variably presenting with similar cognitive and physiological features to Noonan syndrome, a genetic condition resulting in developmental delays, learning disability, cardiovascular abnormalities, and short stature. The pathophysiology of all three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonary Valve Stenosis
Pulmonary valve stenosis (PVS) is a heart valve disorder. Blood going from the heart to the lungs goes through the pulmonary valve, whose purpose is to prevent blood from flowing back to the heart. In pulmonary valve stenosis this opening is too narrow, leading to a reduction of flow of blood to the lungs. While the most common cause of pulmonary valve stenosis is congenital heart disease, it may also be due to a malignant carcinoid tumor. Both stenosis of the pulmonary artery and pulmonary valve stenosis are forms of pulmonic stenosis (nonvalvular and valvular, respectively) but pulmonary valve stenosis accounts for 80% of pulmonic stenosis. PVS was the key finding that led Jacqueline Noonan to identify the syndrome now called Noonan syndrome. Symptoms and signs Among some of the symptoms consistent with pulmonary valve stenosis are the following: * Heart murmur * Cyanosis * Dyspnea * Dizziness * Upper thorax pain * Developmental disorders Cause In regards to the cause ... [...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 substitution, 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. Mutati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Cutaneous Conditions
Many skin conditions affect the human integumentary system—the organ system covering the entire surface of the Human body, body and composed of Human skin, skin, hair, Nail (anatomy), nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square metres, and is made of three distinct layers: the epidermis (skin), epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin.Burns, Tony; ''et al''. (2006) ''Rook's Textbook of Dermatology CD-ROM''. Wiley-Blackwell. . Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. Embryology, In the embryo, the epidermis, hair, and glands form from the ectod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Westerhof Syndrome
Westerhof syndrome is a cutaneous condition inherited in an autosomal dominant fashion, characterized by congenital hypopigmented macules. See also * Watson syndrome * List of cutaneous conditions Many skin conditions affect the human integumentary system—the organ system covering the entire surface of the Human body, body and composed of Human skin, skin, hair, Nail (anatomy), nails, and related muscle and glands. The major function o ... References External links Genodermatoses Genetic disorders with OMIM but no gene Syndromes affecting the skin {{Genodermatoses-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RASopathy
The RASopathies are a group of developmental syndromes caused by germline mutations in genes belonging to the Ras/MAPK pathway. Common features include intellectual disability, congenital heart defects, skin abnormalities, and craniofacial abnormalities. MAPK pathway The most prevalent signaling cascade governed by multi-kinase inhibitors is the mitogen-activated protein kinase (MAPK) pathway. This well-established MAPK pathway in cell biology governs several crucial cellular. It encompasses the RAS/RAF/MEK/ERK signaling cascade. RAF kinase is a primary mediator of the MAPK pathway, responsible for the sequential activation of downstream targets, such as MEK pathway and the transcription factor extracellular signal-related kinase (ERK), which control numerous cellular and physiological processes, including organism development, cell cycle control, cell proliferation, differentiation, migration, survival, apoptosis and cell death. With this cascade, various isoforms of RAS, RAF, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathophysiology
Pathophysiology (or physiopathology) is a branch of study, at the intersection of pathology and physiology, concerning disordered physiological processes that cause, result from, or are otherwise associated with a disease or injury. Pathology is the medical discipline that describes conditions typically ''observed'' during a disease state, whereas physiology is the biological discipline that describes processes or mechanisms ''operating'' within an organism. Pathology describes the abnormal or undesired condition (symptoms of a disease), whereas pathophysiology seeks to explain the functional changes that are occurring within an individual due to a disease or pathologic state. Etymology The term ''pathophysiology'' comes from the Ancient Greek πάθος (''pathos'') and φυσιολογία (''phisiologia''). History Early Developments The origins of pathophysiology as a distinct field date back to the late 18th century. The first known lectures on the subject were delivered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noonan Syndrome
Noonan syndrome (NS) is a genetic disorder that may present with mildly unusual facial features, short height, congenital heart disease, bleeding problems, and skeletal malformations. Facial features include widely spaced eyes, light-colored eyes, low-set ears, a short neck, and a small lower jaw. Heart problems may include pulmonary valve stenosis. The breast bone may either protrude or be sunken, while the spine may be abnormally curved. Intelligence is often normal. Complications of NS can include leukemia. Some of NS' symptoms are shared with Watson syndrome, a related genetic condition. A number of genetic mutations can result in Noonan syndrome. The condition may be inherited as an autosomal dominant condition or occur as a new mutation. Noonan syndrome is a type of RASopathy, the underlying mechanism for which involves sustained activation of the RAS/MAPK cell signaling pathway. The diagnosis may be suspected based on symptoms, medical imaging, and blood test ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cognition
Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, imagination, intelligence, the formation of knowledge, memory and working memory, judgment and evaluation, reasoning and computation, problem-solving and decision-making, comprehension and production of language. Cognitive processes use existing knowledge to discover new knowledge. Cognitive processes are analyzed from very different perspectives within different contexts, notably in the fields of linguistics, musicology, anesthesia, neuroscience, psychiatry, psychology, education, philosophy, anthropology, biology, systemics, logic, and computer science. These and other approaches to the analysis of cognition (such as embodied cognition) are synthesized in the developing field of cognitive science, a progressively autonomou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allele
An allele is a variant of the sequence of nucleotides at a particular location, or Locus (genetics), locus, on a DNA molecule. Alleles can differ at a single position through Single-nucleotide polymorphism, single nucleotide polymorphisms (SNP), but they can also have insertions and deletions of up to several thousand base pairs. Most alleles observed result in little or no change in the function or amount of the gene product(s) they code or regulate for. However, sometimes different alleles can result in different observable phenotypic traits, such as different pigmentation. A notable example of this is Gregor Mendel's discovery that the white and purple flower colors in pea plants were the result of a single gene with two alleles. Nearly all multicellular organisms have two sets of chromosomes at some point in their biological life cycle; that is, they are diploid. For a given locus, if the two chromosomes contain the same allele, they, and the organism, are homozygous with re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Developmental Delay
Global developmental delay is an umbrella term used when children are significantly delayed in two or more areas of development. It can be diagnosed when a child is delayed in one or more milestones, categorised into motor skills, speech delay, speech, cognitive skills, and social and emotional development. There is usually a specific condition which causes this delay, such as cerebral palsy, Fragile X syndrome or other chromosome abnormality, chromosomal abnormalities. However, it is sometimes difficult to identify this underlying condition. Other terms associated with this condition are failure to thrive (which focuses on lack of weight gain and physical development), intellectual disability (which focuses on intellectual deficits and the changes they cause to development) and developmental disability (which can refer to both intellectual and physical disability altering development). Causes Developmental delay can be caused by learning disability, learning disabilities, in which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurofibromatosis Type 1
Neurofibromatosis (NF) refers to a group of three distinct genetic conditions in which tumors grow in the nervous system. The tumors are non-cancerous (benign) and often involve the skin or surrounding bone. Although symptoms are often mild, each condition presents differently. Neurofibromatosis type I (NF1) is typically characterized by café au lait spots (light-brown flat patches of skin), neurofibromas (small bumps in or under the skin), scoliosis (side-way curvature of the back), and headaches. Neurofibromatosis type II (NF2), on the other hand, may present with early-onset hearing loss, cataracts, tinnitus, difficulty walking or maintaining balance, and muscle atrophy. The third type is called schwannomatosis and often presents in early adulthood with widespread pain, numbness, or tingling due to nerve compression. The cause is a genetic mutation in certain oncogenes. These can be inherited, or in about half of cases spontaneously occur during early development. Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurofibromin 1
Neurofibromin (NF-1) is a protein that is encoded in humans, in the ''NF1'' gene. ''NF1'' is located on chromosome 17. Neurofibromin, a GTPase-activating protein that negatively regulates RAS/MAPK pathway activity by accelerating the hydrolysis of Ras superfamily, Ras-bound Guanosine triphosphate, GTP. ''NF1'' has a high mutation rate and mutations can alter cellular growth control, and neural development, resulting in various presentations (depending on the specific allele expressed) such as Watson syndrome and Neurofibromatosis type I, neurofibromatosis type 1 (NF1, also known as von Recklinghausen syndrome). Symptoms of NF1 include disfiguring cutaneous neurofibromas (CNF), Café au lait spot, café au lait pigment spots, plexiform neurofibromas (PN), skeletal defects, optic nerve gliomas, life-threatening malignant peripheral nerve sheath tumors (MPNST), pheochromocytoma, Attention Deficit Syndrome, attention deficits, Learning disability, learning deficits and other cognitiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
