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Tenascin C
Tenascin C (TN-C) is a glycoprotein that in humans is encoded by the ''TNC'' gene. It is expressed in the extracellular matrix of various tissues during development, disease or injury, and in restricted neurogenic areas of the central nervous system. Tenascin-C is the founding member of the tenascin protein family. In the embryo it is made by migrating cells like the neural crest; it is also abundant in developing tendons, bone and cartilage. Gene and expression The human tenascin C gene, ''TN-C'', is located on chromosome 9 with location of the cytogenic band at the 9q33. The entire Tenascin family coding region spans approximately 80 kilobases translating into 2203 amino acids. Expression of TN-C changes from development to adulthood. TN-C is highly expressed during embryogenesis and is briefly expressed during organogenesis, while in developed organs, expression is absent or in trace amounts. TN-C has been shown to be upregulated under pathological conditions caused by i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycoprotein
Glycoproteins are proteins which contain oligosaccharide (sugar) chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. Secreted extracellular proteins are often glycosylated. In proteins that have segments extending extracellularly, the extracellular segments are also often glycosylated. Glycoproteins are also often important integral membrane proteins, where they play a role in cell–cell interactions. It is important to distinguish endoplasmic reticulum-based glycosylation of the secretory system from reversible cytosolic-nuclear glycosylation. Glycoproteins of the cytosol and nucleus can be modified through the reversible addition of a single GlcNAc residue that is considered reciprocal to phosphorylation and the functions of these are likely to be an additional regulatory mechanism that controls phosphorylation-based signalling. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-1
The Interleukin-1 family (IL-1 family) is a group of 11 cytokines that plays a central role in the regulation of immune and inflammatory responses to infections or sterile insults. Discovery Discovery of these cytokines began with studies on the pathogenesis of fever. The studies were performed by Eli Menkin and Paul Beeson in 1943–1948 on the fever-producing properties of proteins released from rabbit peritoneal exudate cells. These studies were followed by contributions of several investigators, who were primarily interested in the link between fever and infection/inflammation. The basis for the term "interleukin" was to streamline the growing number of biological properties attributed to soluble factors from macrophages and lymphocytes. IL-1 was the name given to the macrophage product, whereas IL-2 was used to define the lymphocyte product. At the time of the assignment of these names, there was no amino acid sequence analysis known and the terms were used to define b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptide
Peptides are short chains of amino acids linked by peptide bonds. A polypeptide is a longer, continuous, unbranched peptide chain. Polypeptides that have a molecular mass of 10,000 Da or more are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. Peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic peptides have an N-terminal (amine group) and C-terminal (carboxyl g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligomeric
In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomer, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of units derived, actually or conceptually, from molecules of lower relative molecular mass.'' The name is composed of Greek language, Greek elements ''wikt:oligo-, oligo-'', "a few" and ''wikt:-mer, -mer'', "parts". An adjective form is ''oligomeric''. The oligomer concept is contrasted to that of a polymer, which is usually understood to have a large number of units, possibly thousands or millions. However, there is no sharp distinction between these two concepts. One proposed criterion is whether the molecule's properties vary significantly with the removal of one or a few of the units. An oligomer with a specific number of units is referred t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gliomas
A glioma is a type of primary tumor, primary Neoplasm, tumor that starts in the glial cells of the Human brain, brain or spinal cord. They are Malignancy, malignant but some are extremely slow to develop. Gliomas comprise about 30% of all brain tumor, brain and central nervous system, central Nervous system tumor, nervous system tumors and 80% of all malignant brain tumors. They are a few common types that include astrocytoma (cancer of Astrocyte, astrocytes), glioblastoma (an aggressive form of astrocytoma), oligodendroglioma (cancer of Oligodendrocyte, oligodendrocytes), and ependymoma (cancer of Ependyma, ependymal cells). Signs and symptoms Symptoms of gliomas depend on the part of the central nervous system (CNS) that is affected. A brain glioma can cause headaches, nausea, vomiting, memory loss, seizures, Visual impairment, vision problems, speech disorder, speech difficulties, and cranial nerve disorders as a result of increased intracranial pressure. Cognitive impairmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothalamus
The hypothalamus (: hypothalami; ) is a small part of the vertebrate brain that contains a number of nucleus (neuroanatomy), nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus and is part of the limbic system. It forms the Basal (anatomy), basal part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is about the size of an Almond#Nut, almond. The hypothalamus has the function of regulating certain metabolic biological process, processes and other activities of the autonomic nervous system. It biosynthesis, synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland. The hypothalamus controls thermoregulation, body temperature, hunger (physiology), hunger, important aspects o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Differentiation
Cellular differentiation is the process in which a stem cell changes from one type to a differentiated one. Usually, the cell changes to a more specialized type. Differentiation happens multiple times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover. Some differentiation occurs in response to antigen exposure. Differentiation dramatically changes a cell's size, shape, membrane potential, metabolic activity, and responsiveness to signals. These changes are largely due to highly controlled modifications in gene expression and are the study of epigenetics. With a few exceptions, cellular differentiation almost never involves a change in the DNA sequence itself. Metabolic composition, however, gets dramatically altered where st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gliogenesis
Gliogenesis is the generation of non-neuronal glia populations derived from multipotent neural stem cells. Overview Gliogenesis results in the formation of non-neuronal glia populations from neuronal cells. In this capacity, glial cells provide multiple functions to both the central nervous system (CNS) and the peripheral nervous system (PNS). Subsequent differentiation of glial cell populations results in function-specialized glial lineages. Glial cell-derived astrocytes are specialized lineages responsible for modulating the chemical environment by altering ion gradients and neurotransmitter transduction. Similarly derived, oligodendrocytes produce myelin, which insulates axons to facilitate electric signal transduction. Finally, microglial cells are derived from glial precursors and carry out macrophage-like properties to remove cellular and foreign debris within the central nervous system ref. Functions of glial-derived cell lineages are reviewed by Baumann and Hauw. Gliogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glia
Glia, also called glial cells (gliocytes) or neuroglia, are non-neuronal cells in the central nervous system (the brain and the spinal cord) and in the peripheral nervous system that do not produce electrical impulses. The neuroglia make up more than one half the volume of neural tissue in the human body. They maintain homeostasis, form myelin, and provide support and protection for neurons. In the central nervous system, glial cells include oligodendrocytes (that produce myelin), astrocytes, ependymal cells and microglia, and in the peripheral nervous system they include Schwann cells (that produce myelin), and satellite cells. Function They have four main functions: * to surround neurons and hold them in place * to supply nutrients and oxygen to neurons * to insulate one neuron from another * to destroy pathogens and remove dead neurons. They also play a role in neurotransmission and synaptic connections, and in physiological processes such as breathing. While glia we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrocytes
Astrocytes (from Ancient Greek , , "star" and , , "cavity", "cell"), also known collectively as astroglia, are characteristic star-shaped glial cells in the brain and spinal cord. They perform many functions, including biochemical control of endothelial cells that form the blood–brain barrier, provision of nutrients to the nervous tissue, maintenance of extracellular ion balance, regulation of cerebral blood flow, and a role in the repair and Glial scar, scarring process of the brain and spinal cord following infection and traumatic injuries. The proportion of astrocytes in the brain is not well defined; depending on the counting technique used, studies have found that the astrocyte proportion varies by region and ranges from 20% to around 40% of all glia. Another study reports that astrocytes are the most numerous cell type in the brain. Astrocytes are the major source of cholesterol in the central nervous system. Apolipoprotein E transports cholesterol from astrocytes to neuro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligodendrocyte Progenitor
Oligodendrocyte progenitor cells (OPCs), also known as oligodendrocyte precursor cells, NG2-glia, O2A cells, or polydendrocytes, are a subtype of glia in the central nervous system named for their essential role as precursors to oligodendrocytes and myelin. They are typically identified in the human by co-expression of PDGFRA and CSPG4. OPCs play a critical role in developmental and adult myelinogenesis. They give rise to oligodendrocytes, which then wrap around axons and provide electrical insulation by forming a myelin sheath. This enables faster action potential propagation and high fidelity transmission without a need for an increase in axonal diameter. The loss or lack of OPCs, and consequent lack of differentiated oligodendrocytes, is associated with a loss of myelination and subsequent impairment of neurological functions. In addition, OPCs express receptors for various neurotransmitters and undergo membrane depolarization when they receive synaptic inputs from neurons. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrin
Integrins are transmembrane receptors that help cell–cell and cell–extracellular matrix (ECM) adhesion. Upon ligand binding, integrins activate signal transduction pathways that mediate cellular signals such as regulation of the cell cycle, organization of the intracellular cytoskeleton, and movement of new receptors to the cell membrane. The presence of integrins allows rapid and flexible responses to events at the cell surface (''e.g''. signal platelets to initiate an interaction with coagulation factors). Several types of integrins exist, and one cell generally has multiple different types on its surface. Integrins are found in all animals while integrin-like receptors are found in plant cells. Integrins work alongside other proteins such as cadherins, the immunoglobulin superfamily cell adhesion molecules, selectins and syndecans, to mediate cell–cell and cell–matrix interaction. Ligands for integrins include fibronectin, vitronectin, collagen and laminin. Stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
