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S100 Proteins
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, #Human genes, ''S100A1'', ''S100A2'', ''S100A3''. They are also considered as DAMPs#S100 Molecules, 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, calmod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Langerhans Cell
A Langerhans cell (LC) is a tissue-resident macrophage of the skin once thought to be a resident dendritic cell. These cells contain organelles called Birbeck granules. They are present in all layers of the epidermis and are most prominent in the stratum spinosum. They also occur in the papillary dermis, particularly around blood vessels, as well as in the oral mucosa, mucosa of the mouth, foreskin, and vaginal epithelium. They can be found in other tissues, such as lymph nodes, particularly in association with the condition Langerhans cell histiocytosis (LCH). Function In skin infections, the local Langerhans cells take up and process microbe, microbial antigens to become fully functional antigen-presenting cells. Generally, tissue-resident macrophages are involved in immune homeostasis and the uptake of Apoptosis, apoptotic bodies. However, Langerhans cells can also take on a dendritic cell-like phenotype and migrate to lymph nodes to interact with naive T-cells. Matrix meta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S100A2
S100 calcium-binding protein A2 (S100A2) is a protein that in humans is encoded by the ''S100A2'' gene and it is located on chromosome 1q21 with other S100 proteins. Tissue and subcellular distribution S100A2, also known as CaN19 or S100L was first isolated from bovine lung tissue. However, in human tissue it was discovered several years later, in the mammary epithelial cells. Under normal circumstances it is highly expressed in human lungs, prostate, kidneys, hair follicles and salivary and mammary glands. S100A2 is predominantly found in the nucleus, which is not very common in other S100 proteins. Moreover, it can also be found in the cytoplasm, and its distribution is rather diffuse. Its occurrence in cytoplasm is most likely dependent on calcium levels in the cell. In the extracellular environment, it can be found as a homodimer ''in vivo'' and ''in vitro'', but it also exists in monomeric, polymeric and multimeric forms. In multimeric form, it functions as a RAGE rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S100A1
Protein S100-A1, also known as S100 calcium-binding protein A1 is a protein which in humans is encoded by the ''S100A1'' gene. S100A1 is highly expressed in cardiac and skeletal muscle, and localizes to Z-discs and sarcoplasmic reticulum. S100A1 has shown promise as an effective candidate for gene therapy to treat post- myocardially infarcted cardiac tissue. Structure S100A1 is a member of the S100 family of proteins expressed in cardiac muscle, skeletal muscle and brain, with highest density at Z-lines and sarcoplasmic reticulum. S100A1 contains 4 EF-hand calcium-binding motifs in its dimerized form, and can exist as either a hetero or homo dimer. The S100A1 homodimer is high affinity (nanomolar range or tighter), and is formed through hydrophobic packing of an X-type 4-helix bundle created between helices 1, 1', 4, and 4'. Protein nuclear magnetic resonance spectroscopy structural information on the homodimeric form of this protein shows that each monomer is helical a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomic Pathology
Anatomical pathology (''Commonwealth'') or anatomic pathology (''U.S.'') is a medical specialty that is concerned with the diagnosis of disease based on the macroscopic, microscopic, biochemical, immunologic and molecular examination of organs and tissues. Over the 20th century, surgical pathology has evolved tremendously: from historical examination of whole bodies (autopsy) to a more modernized practice, centered on the diagnosis and prognosis of cancer to guide treatment decision-making in oncology. Its modern founder was the Italian scientist Giovanni Battista Morgagni from Forlì. Anatomical pathology is one of two branches of pathology, the other being clinical pathology, the diagnosis of disease through the laboratory analysis of bodily fluids or tissues. Often, pathologists practice both anatomical and clinical pathology, a combination known as general pathology. Similar specialties exist in veterinary pathology. Differences with clinical pathology Anato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clear-cell Sarcoma
Clear cell sarcoma is a sub-type of a rare form of cancer called a sarcoma. It is known to occur mainly in the soft tissues and dermis. Rare forms were thought to occur in the gastrointestinal tract before they were discovered to be different and redesignated as gastrointestinal neuroectodermal tumors. Recurrence is common. Clear cell sarcoma's neoplastic cells express the '' EWSR1-ATF1'' fusion gene in a majority of cases or a ''EWSR1-CREB1'', ''EWSR1-CREM'', or ''EWSR1-DDIT3'' fusion gene in a small subset of cases (see FET gene family of fusion genes). Clear cell sarcoma of the soft tissues in adults is not related to the pediatric tumor known as clear cell sarcoma of the kidney. Signs and symptoms It presents as a slow growing mass that especially affects tendons and aponeuroses and it is deeply situated. Patients often perceive it as a lump or hard mass. It causes either pain or tenderness but only until it becomes large enough. This kind of tumor is commonly found in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histiocytoma
A histiocytoma is a tumour consisting of histiocytes. Histiocytes are cells that are a part of the mononuclear phagocytic system, a part of the body's immune system that consists of phagocytic cells, which are responsible for engulfing solid particles by the cell membrane to form an internal phagosome by phagocytes and protists. Myxofibrosarcoma had been classified as a type of histiocytoma. However, the World Health Organization (2020) reclassified myxofibrosarcoma as a malignant tumor in the category of fibroblastic/myofibroblastic tumors. Types include: * benign fibrous histiocytoma: This tumor has also been termed benign fibrous histiocytomas of the skin, superficial/cutaneous benign fibrous histiocytomas, common fibrous histiocytoma, and more recently dermatofibroma. The use of "histiocytoma" in these terms refers more to the morphologic appearance of some of the cells that comprise these lesions rather than their lineage: studies to date have not fully determined the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malignant Peripheral Nerve Sheath Tumor
A malignant peripheral nerve sheath tumor (MPNST) is a form of cancer of the connective tissue surrounding peripheral nerves. Given its origin and behavior it is classified as a sarcoma. About half the cases are diagnosed in people with neurofibromatosis; the lifetime risk for an MPNST in patients with neurofibromatosis type 1 is 8–13%. MPNST with rhabdomyoblastomatous component are called malignant triton tumors. The first-line treatment is surgical resection with wide margins. Chemotherapy and often radiotherapy are done as adjuvant and/or neoadjuvant treatment depending upon various risk factors. Signs and symptoms Symptoms may include: * Swelling in the extremities (arms or legs), also called peripheral edema; the swelling often is painless. * Difficulty in moving the extremity that has the tumor, including a limp. * Soreness localized to the area of the tumor or in the extremity. * Neurological symptoms. * Pain or discomfort: numbness, burning, or "pins and need ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwannomas
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanoma
Melanoma is the most dangerous type of skin cancer; it develops from the melanin-producing cells known as melanocytes. It typically occurs in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In very rare cases melanoma can also happen in the lung which is known as primary pulmonary melanoma and only happens in 0.01% of primary lung tumors. In women, melanomas most commonly occur on the legs; while in men, on the back. Melanoma is frequently referred to as malignant melanoma. However, the medical community stresses that there is no such thing as a 'benign melanoma' and recommends that the term 'malignant melanoma' should be avoided as redundant. About 25% of melanomas develop from nevus, moles. Changes in a mole that can indicate melanoma include increaseespecially rapid increasein size, irregular edges, change in color, itchiness, or nevus#Classification, skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraganglioma - S100 - Very High Mag
A paraganglioma is a rare neuroendocrine neoplasm that may develop at various body sites (including the head, neck, thorax and abdomen). When the same type of tumor is found in the adrenal gland, they are referred to as a pheochromocytoma. They are rare tumors, with an overall estimated incidence of 1 in 300,000. There is no test that determines benign from malignant tumors; long-term follow-up is therefore recommended for all individuals with paraganglioma. Signs and symptoms Most paragangliomas are asymptomatic, present as a painless mass, or create symptoms such as hypertension, tachycardia, headache, and palpitations. While all contain neurosecretory granules, only in 1–3% of cases is secretion of hormones such as catecholamines abundant enough to be clinically significant; in that case manifestations often resemble those of pheochromocytomas (intra-medullary paraganglioma). Genetics About 75% of paragangliomas are sporadic; the remaining 25% are hereditary (and have an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelium
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of many internal organs, the corresponding inner surfaces of body cavities, and the inner surfaces of blood vessels. Epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. These tissues also lack blood or lymph supply. The tissue is supplied by nerves. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either simple squamous, simple columnar, or simple cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
