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Human Melanoma Black
HMB-45 is a monoclonal antibody that reacts against an antigen present in melanocytic tumors such as melanomas, and stands for Human Melanoma Black. It is used in anatomic pathology as a marker for such tumors. The specific antigen recognized by HMB-45 is now known as Pmel 17. History HMB-45 was discovered by Drs. Allen M. Gown and Arthur M. Vogel in 1986. The antibody was generated to an extract of melanoma. Cancer diagnostics In a study to determine diagnostic usefulness of specific antibodies used to identify melanoma, HMB-45 had a 92% sensitivity when used to identify melanoma. The antibody also reacts positively against junctional nevus cells and fetal melanocytes. Despite this relatively high sensitivity—HMB-45 does have its drawbacks. HMB-45 can be detected in only 50-70% of melanomas. HMB-45 does not react well against intradermal nevi, normal adult melanocytes, spindle cell melanomas and desmoplastic melanomas. HMB-45 is nonreactive with almost all non-melanoma huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclonal Antibody
A monoclonal antibody (mAb, more rarely called moAb) is an antibody produced from a cell Lineage made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell. Monoclonal antibodies can have monovalent affinity, binding only to the same epitope (the part of an antigen that is recognized by the antibody). In contrast, polyclonal antibodies bind to multiple epitopes and are usually made by several different antibody-secreting plasma cell lineages. Bispecific monoclonal antibodies can also be engineered, by increasing the therapeutic targets of one monoclonal antibody to two epitopes. It is possible to produce monoclonal antibodies that specifically bind to virtually any suitable substance; they can then serve to detect or purify it. This capability has become an investigative tool in biochemistry, molecular biology, and medicine. Monoclonal antibodies are being used on a clinical level for both the diagnosis and therapy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiomyolipoma
Angiomyolipomas are the most common benign tumour of the kidney. Although regarded as benign, angiomyolipomas may grow such that kidney function is impaired or the blood vessels may dilate and burst, leading to bleeding. Angiomyolipomas are strongly associated with the genetic disease Tuberous Sclerosis, in which most individuals have several Angiomyolipomas affecting both kidneys. They are also commonly found in women with the rare lung disease lymphangioleiomyomatosis. Angiomyolipomas are less commonly found in the liver and rarely in other organs. Whether associated with these diseases or sporadic, Angiomyolipomas are caused by mutations in either the ''TSC1'' or ''TSC2 ''genes, which govern cell growth and proliferation. They are composed of blood vessels, smooth muscle cells, and fat cells. Large Angiomyolipomas can be treated with embolisation. Drug therapy for Angiomyolipomas is at the research stage. The Tuberous Sclerosis Alliance has published guidelines on diagnos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Histologic Stains That Aid In Diagnosis Of Cutaneous Conditions
A number of histologic stains are used in the field of dermatology that aid in the diagnosis of conditions of or affecting the human integumentary system. Footnotes See also * List of conditions associated with café au lait macules * List of contact allergens *List of cutaneous conditions associated with increased risk of nonmelanoma skin cancer *List of cutaneous conditions associated with internal malignancy *List of cutaneous conditions caused by mutations in keratins *List of cutaneous neoplasms associated with systemic syndromes *List of cutaneous conditions caused by problems with junctional proteins *List of dental abnormalities associated with cutaneous conditions *List of genes mutated in cutaneous conditions *List of genes mutated in pigmented cutaneous lesions *List of human leukocyte antigen alleles associated with cutaneous conditions *List of immunofluorescence findings for autoimmune bullous conditions * List of inclusion bodies that aid in diagnosis of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitf
Microphthalmia-associated transcription factor also known as class E basic helix-loop-helix protein 32 or bHLHe32 is a protein that in humans is encoded by the ''MITF'' gene. MITF is a basic helix-loop-helix leucine zipper transcription factor involved in lineage-specific pathway regulation of many types of cells including melanocytes, osteoclasts, and mast cells. The term "lineage-specific", since it relates to MITF, means genes or traits that are only found in a certain cell type. Therefore, MITF may be involved in the rewiring of signaling cascades that are specifically required for the survival and physiological function of their normal cell precursors. MITF, together with transcription factor EB (TFEB), TFE3 and TFEC, belong to a subfamily of related bHLHZip proteins, termed the MiT-TFE family of transcription factors. The factors are able to form stable DNA-binding homo- and heterodimers. The gene that encodes for MITF resides at the ''mi'' locus in mice, and its protumoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrosinase
Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin. The enzyme is mainly involved in two distinct reactions of melanin synthesis otherwise known as the Raper Mason pathway. Firstly, the hydroxylation of a monophenol and secondly, the conversion of an o-diphenol to the corresponding o-quinone. o-Quinone undergoes several reactions to eventually form melanin. Tyrosinase is a copper-containing enzyme present in plant and animal tissues that catalyzes the production of melanin and other pigments from tyrosine by oxidation. It is found inside melanosomes which are synthesized in the skin melanocytes. In humans, the tyrosinase enzyme is encoded by the ''TYR'' gene. Catalyzed reaction Tyrosinase carries out the oxidation of phenols such as tyrosine and dopamine using dioxygen (O2). In the presence of catechol, benzoquinone is formed (see reaction below). Hydrogens removed from catechol combine with oxygen to form water. The substrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MLANA
Protein melan-A also known as melanoma antigen recognized by T cells 1 or MART-1 is a protein that in humans is encoded by the ''MLANA'' or "MALENA" gene. A fragment of the protein, usually consisting of the nine amino acids 27 to 35, is bound by MHC class I complexes which present it to T cells of the immune system. These complexes can be found on the surface of melanoma cells. Decameric peptides (26-35) are being investigated as cancer vaccines. Discovery and nomenclature The names MART-1 and melan-A were coined by two groups of researchers who independently sequenced the gene for this antigen in 1994. Both names are currently in common use. Kawakami et al. at the National Cancer Institute coined the term MART-1, which stands for "melanoma antigen recognized by T-cells." Coulie et al. of Belgium called the gene melan-A, presumably an abbreviation for "melanocyte antigen." Clinical significance MART-1/melan-A is a protein antigen that is found on the surface of melanocyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S100 Protein
The S100 proteins are a family of low molecular-weight proteins found in vertebrates characterized by two calcium-binding sites that have helix-loop-helix ("EF-hand-type") conformation. At least 21 different S100 proteins are known. They are encoded by a family of genes whose symbols use the ''S100'' prefix, for example, ''S100A1'', ''S100A2'', ''S100A3''. They are also considered as damage-associated molecular pattern molecules (DAMPs), and knockdown of aryl hydrocarbon receptor downregulates the expression of S100 proteins in THP-1 cells. Structure Most S100 proteins consist of two identical polypeptides (homodimeric), which are held together by noncovalent bonds. They are structurally similar to calmodulin. They differ from calmodulin, though, on the other features. For instance, their expression pattern is cell-specific, i.e. they are expressed in particular cell types. Their expression depends on environmental factors. In contrast, calmodulin is a ubiquitous and universa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuberous Sclerosis
Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that causes non-cancerous tumours to grow in the brain and on other vital organs such as the kidneys, heart, liver, eyes, lungs and skin. A combination of symptoms may include seizures, intellectual disability, developmental delay, behavioral problems, skin abnormalities, lung disease, and kidney disease. TSC is caused by a mutation of either of two genes, ''TSC1'' and ''TSC2'', which code for the proteins hamartin and tuberin, respectively, with ''TSC2'' mutations accounting for the majority and tending to cause more severe symptoms. These proteins act as tumor growth suppressors, agents that regulate cell proliferation and differentiation. Prognosis is highly variable and depends on the symptoms, but life expectancy is normal for many. The prevalence of the disease is estimated to be 7 to 12 in 100,000. The disease is often abbreviated to tuberous sclerosis, which refers to the har ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanocyte
Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and heart. Melanin is a dark pigment primarily responsible for skin color. Once synthesized, melanin is contained in special organelles called melanosomes which can be transported to nearby keratinocytes to induce pigmentation. Thus darker skin tones have more melanosomes present than lighter skin tones. Functionally, melanin serves as protection against UV radiation. Melanocytes also have a role in the immune system. Function Through a process called melanogenesis, melanocytes produce melanin, which is a pigment found in the skin, eyes, hair, nasal cavity, and inner ear. This melanogenesis leads to a long-lasting pigmentation, which is in contrast to the pigmentation that originates from oxidation of already-existing melanin. There are both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcoma
A sarcoma is a malignant tumor, a type of cancer that arises from transformed cells of mesenchymal (connective tissue) origin. Connective tissue is a broad term that includes bone, cartilage, fat, vascular, or hematopoietic tissues, and sarcomas can arise in any of these types of tissues. As a result, there are many subtypes of sarcoma, which are classified based on the specific tissue and type of cell from which the tumor originates. Sarcomas are ''primary'' connective tissue tumors, meaning that they arise in connective tissues. This is in contrast to ''secondary'' (or "metastatic") connective tissue tumors, which occur when a cancer from elsewhere in the body (such as the lungs, breast tissue or prostate) spreads to the connective tissue. The word ''sarcoma'' is derived from the Greek σάρκωμα ''sarkōma'' "fleshy excrescence or substance", itself from σάρξ ''sarx'' meaning "flesh". Classification Sarcomas are typically divided into two major groups: bone sarcom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwannoma
A schwannoma (or neurilemmoma) is a usually benign nerve sheath tumor composed of Schwann cells, which normally produce the insulating myelin sheath covering peripheral nerves. Schwannomas are homogeneous tumors, consisting only of Schwann cells. The tumor cells always stay on the outside of the nerve, but the tumor itself may either push the nerve aside and/or up against a bony structure (thereby possibly causing damage). Schwannomas are relatively slow-growing. For reasons not yet understood, schwannomas are mostly benign and less than 1% become malignant, degenerating into a form of cancer known as neurofibrosarcoma. These masses are generally contained within a capsule, so surgical removal is often successful. Schwannomas can be associated with neurofibromatosis type II, which may be due to a loss-of-function mutation in the protein merlin. They are universally S-100 positive, which is a marker for cells of neural crest cell origin. Schwannomas of the head and neck are a fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
