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Griscelli Syndrome Type 2
Griscelli syndrome type 2 (also known as "partial albinism with immunodeficiency") is a rare autosomal recessive syndrome characterized by variable cutenous albinism, silver colored metallic looking hair, frequent bacterial or viral infections, neutropenia, and thrombocytopenia.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . Presentation All types of Griscelli syndrome have distinctive skin and hair coloring. Type 1 is associated with neurological abnormalities. These include delayed development, intellectual disability, seizures, hypotonia and eye abnormalities. Type 2 - unlike type 1 - is not associated with primary neurological disease but is associated with an uncontrolled T lymphocyte expansion and macrophage activation syndrome. It is often associated with the hemophagocytic syndrome. This latter condition may be fatal in the absence of bone marrow transplantation. Persons with type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutropenia
Neutropenia is an abnormally low concentration of neutrophils (a type of white blood cell) in the blood. Neutrophils make up the majority of circulating white blood cells and serve as the primary defense against infections by destroying bacteria, bacterial fragments and immunoglobulin-bound viruses in the blood. People with neutropenia are more susceptible to bacterial infections and, without prompt medical attention, the condition may become life-threatening ( neutropenic sepsis). Neutropenia can be divided into congenital and acquired, with severe congenital neutropenia (SCN) and cyclic neutropenia (CyN) being autosomal dominant and mostly caused by heterozygous mutations in the ELANE gene ( neutrophil elastase). Neutropenia can be acute (temporary) or chronic (long lasting). The term is sometimes used interchangeably with "leukopenia" ("deficit in the number of white blood cells"). Decreased production of neutrophils is associated with deficiencies of vitamin B12 and fol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients. A normal human platelet count ranges from 150,000 to 450,000 platelets/microliter (μl) of blood. Values outside this range do not necessarily indicate disease. One common definition of thrombocytopenia requiring emergency treatment is a platelet count below 50,000/μl. Thrombocytopenia can be contrasted with the conditions associated with an abnormally ''high'' level of platelets in the blood - thrombocythemia (when the cause is unknown), and thrombocytosis (when the cause is known). Signs and symptoms Thrombocytopenia usually has no symptoms and is picked up on a routine complete blood count. Some individuals with thrombocytopenia may experience external bleeding, such as nosebleeds or bleeding gum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adaptive immune system, adaptive immunity), and B cells (for humoral immunity, humoral, antibody-driven adaptive immune system, adaptive immunity). They are the main type of cell found in lymph, which prompted the name "lymphocyte". Lymphocytes make up between 18% and 42% of circulating white blood cells. Types The three major types of lymphocyte are T cell A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell r ...s, B cells and Natural killer cell, natural killer (NK) cells. Lymphocytes can be identified by their large nucleus. T cells and B cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage Activation Syndrome
Macrophage activation syndrome is a severe, potentially life-threatening, complication of several chronic rheumatic diseases of childhood. It occurs most commonly with systemic-onset juvenile idiopathic arthritis (SoJIA). In addition, MAS has been described in association with systemic lupus erythematosus (SLE), Kawasaki disease, and adult-onset Still's disease. It is thought to be closely related and pathophysiologically very similar to reactive (secondary) hemophagocytic lymphohistiocytosis (HLH). The incidence of MAS is unknown as there is a wide spectrum of clinical manifestations, and episodes may remain unrecognized. Signs and symptoms The hallmark clinical and laboratory features include high fever, hepatosplenomegaly, lymphadenopathy, pancytopenia, liver dysfunction, disseminated intravascular coagulation, hypofibrinogenemia, hyperferritinemia, and hypertriglyceridemia. Despite marked systemic inflammation, the erythrocyte sedimentation rate (ESR) is paradoxically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemophagocytic Syndrome
Hemophagocytic lymphohistiocytosis (HLH), also known as haemophagocytic lymphohistiocytosis (British spelling), and hemophagocytic or haemophagocytic syndrome, is an uncommon hematologic disorder seen more often in children than in adults. It is a life-threatening disease of severe hyperinflammation caused by uncontrolled proliferation of activated lymphocytes and macrophages, characterised by proliferation of morphologically benign lymphocytes and macrophages that secrete high amounts of inflammatory cytokines. It is classified as one of the cytokine storm syndromes. There are inherited and non-inherited (acquired) causes of hemophagocytic lymphohistiocytosis (HLH). Signs and symptoms The onset of HLH occurs before the age of one year in approximately 70 percent of cases. Familial HLH should be suspected if siblings are diagnosed with HLH or if symptoms recur when therapy has been stopped. Familial HLH is an autosomal recessive disease, hence each sibling of a child with familia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elejalde Syndrome
Elejalde syndrome or neuroectodermal melanolysosomal disease is an extremely rare autosomal recessive syndrome (only around 10 cases known) consisting of moderate pigment dilution, profound central nervous system dysfunction, no immune defects, and hair with a metallic silvery sheen.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . The changes to hair and skin pigmentation are associated with altered melanosome trafficking. It is associated with MYO5A Unconventional myosin-Va is a motor protein in charge of the intracellular transport of vesicles, organelles and protein complexes along the actin filaments. In humans it is coded for by the ''MYO5A'' gene. Structure In the presence of cargo ada .... See also * Griscelli syndrome References External links Disturbances of human pigmentation Cytoskeletal defects Rare syndromes {{Cutaneous-condition-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MYO5A
Unconventional myosin-Va is a motor protein in charge of the intracellular transport of vesicles, organelles and protein complexes along the actin filaments. In humans it is coded for by the ''MYO5A'' gene. Structure In the presence of cargo adapters and calcium, unconventional myosin Va is present in an elongated and active state. It has an N-terminal head domain and a C-terminal tail domain. The actin-binding head (N-Terminal) is an ATP-dependent motor domain that transmits changes from the active site to the light chain lever arm. The C-terminal globular domain (GB) decides the Myosin class and moderate the cargo transport. Also, the GB interacts with other cargo specific proteins. Myosin Va is highly expressed in neurons and melanocytes. Interactions MYO5A has been shown to interact with DYNLL1, RAB27A, DYNLL2, RPGRIP1L,Assis, L. H. P. et al. The molecular motor Myosin Va interacts with the cilia-centrosomal protein RPGRIP1L. Sci. Rep. 7, 43692; doi: 10.1038/srep43692 (2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RAB27A
Ras-related protein Rab-27A is a protein that in humans is encoded by the ''RAB27A'' gene. Function The protein encoded by this gene belongs to the small GTPase superfamily, Rab family. The protein is membrane-bound and may be involved in protein transport and small GTPase mediated signal transduction. Mutations in this gene are associated with Griscelli syndrome type 2 and hemophagocytic lymphohistiocytosis. Alternative splicing occurs at this locus and four transcript variants encoding the same protein have been identified. The RAB27A gene is regulated by the Microphthalmia-associated transcription factor. Interactions RAB27A has been shown to interact with: * EXPH5, * MYO5A Unconventional myosin-Va is a motor protein in charge of the intracellular transport of vesicles, organelles and protein complexes along the actin filaments. In humans it is coded for by the ''MYO5A'' gene. Structure In the presence of cargo ada ..., * RPH3AL * SYTL1, and * SYTL2. See a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 15
Chromosome 15 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 15 spans about 102 million base pairs (the building material of DNA) and represents between 3% and 3.5% of the total DNA in cells. Chromosome 15 is an acrocentric chromosome, with a very small short arm (the "p" arm, for "petite"), which contains few protein coding genes among its 19 million base pairs. It has a larger long arm (the "q" arm) that is gene rich, spanning about 83 million base pairs. The human leukocyte antigen gene for β2-microglobulin is found on chromosome 15, as well as the FBN1 gene, coding for both fibrillin-1 (a protein critical to the proper functioning of connective tissue), and aprosin (a small protein produced from part of the transcribed FBN1 gene mRNA), which is involved in fat metabolism. Genes Number of genes The following are some of the gene count estimates of human chromosome 15. Because researchers use different appro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Griscelli Syndrome Type 3
Griscelli syndrome type 3 is a disorder of melanosome transport presenting initially with hypopigmentation.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . See also *Griscelli syndrome Griscelli syndrome is a rare autosomal recessive disorder characterized by albinism (hypopigmentation) with immunodeficiency, that usually causes death by early childhood. Researchers have developed three different classifications of the form of di ... References External links Disturbances of human pigmentation Syndromes {{Cutaneous-condition-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MLPH
Melanophilin is a carrier protein which in humans is encoded by the ''MLPH'' gene. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined. Function This gene encodes a member of the exophilin subfamily of Rab effector proteins. The protein forms a ternary complex with the small Ras-related GTPase Rab27A in its GTP-bound form and the motor protein myosin Va. A similar protein complex in mouse functions to tether pigment-producing organelles called melanosomes to the actin cytoskeleton in melanocytes, and is required for visible pigmentation in the hair and skin. In melanocytic cells MLPH gene expression may be regulated by MITF. Clinical significance A mutation in this gene results in Griscelli syndrome type 3, which is characterized by a silver-gray hair color and abnormal pigment distribution in the hair shaft. Mutations in melanophilin cause the "dilute" coat color ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
