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Cord Factor
Cord factor, or trehalose dimycolate, is a glycolipid molecule found in the cell wall of '' Mycobacterium tuberculosis'' and similar species. It is the primary lipid found on the exterior of ''M. tuberculosis'' cells. Cord factor influences the arrangement of ''M. tuberculosis'' cells into long and slender formations, giving its name. Cord factor is virulent towards mammalian cells and critical for survival of ''M. tuberculosis'' in hosts, but not outside of hosts. Cord factor has been observed to influence immune responses, induce the formation of granulomas, and inhibit tumor growth. The antimycobacterial drug SQ109 is thought to inhibit TDM production levels and in this way disrupts its cell wall assembly. Structure A cord factor molecule is composed of a sugar molecule, trehalose (a disaccharide), composed of two glucose molecules linked together. Trehalose is esterified to two mycolic acid residues. One of the two mycolic acid residues is attached to the sixth carbon o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chording Mycobacterium Tuberculesis Culture
Chording means pushing several keys or buttons simultaneously to achieve a result. Musical keyboards In music, more than one key are pressed at a time to achieve more complex sounds, or chords. Computer keyboards Chording, with a chorded keyboard or keyer allows one to produce as many characters as a QWERTY keyboard but with fewer keys and less motion per finger. Pointers Mouse chording allows a user to use a two-button mouse, trackball, or touchpad as if it where a three-button device. For example, in the Unix graphical user interface (known as X11), the middle button is used to paste text. Since Microsoft-type mice traditionally only had two buttons, users of Unix-type systems such as Linux and BSD ''chord'' the right and left buttons to paste text. Multitouch chording TipTapSpeech an application for the iPhone and iPad is a chord-based text entry solution for touch screen computing. A GKOS chording keyboard application development for iPhone was started on the GK ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphiphilic
An amphiphile (from the Greek αμφις amphis, both, and φιλíα philia, love, friendship), or amphipath, is a chemical compound possessing both hydrophilic (''water-loving'', polar) and lipophilic (''fat-loving'') properties. Such a compound is called amphiphilic or amphipathic. Common amphiphilic substances are soaps, detergents, and lipoproteins. The phospholipid amphiphiles are the major structural component of cell membranes. Amphiphiles are the basis for a number of areas of research in chemistry and biochemistry, notably that of lipid polymorphism. Organic compounds containing hydrophilic groups at both ends of the molecule are called bolaamphiphilic. The micelles they form in the aggregate are prolate. Structure The lipophilic group is typically a large hydrocarbon moiety, such as a long chain of the form CH3(CH2)n, with n > 4. The hydrophilic group falls into one of the following categories: # charged groups #* anionic. Examples, with the lipophilic part of the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granulomas
A granuloma is an aggregation of macrophages that forms in response to chronic inflammation. This occurs when the immune system attempts to isolate foreign substances that it is otherwise unable to eliminate. Such substances include infectious organisms including bacteria and fungi, as well as other materials such as foreign objects, keratin, and suture fragments. Definition In pathology, a granuloma is an organized collection of macrophages. In medical practice, doctors occasionally use the term ''granuloma'' in its more literal meaning: "a small nodule". Since a small nodule can represent any tissue from a harmless nevus to a malignant tumor, this use of the term is not very specific. Examples of this use of the term ''granuloma'' are the lesions known as vocal cord granuloma (known as contact granuloma), pyogenic granuloma, and intubation granuloma, all of which are examples of granulation tissue, not granulomas. "Pulmonary hyalinizing granuloma" is a lesion characterized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage Inflammatory Protein-2
Chemokine (C-X-C motif) ligand 3 (CXCL3) is a small cytokine belonging to the CXC chemokine family that is also known as ''GRO3 oncogene'' (GRO3), ''GRO protein gamma'' (GROg) and ''macrophage inflammatory protein-2-beta'' (MIP2b). CXCL3 controls migration and adhesion of monocytes and mediates its effects on its target cell by interacting with a cell surface chemokine receptor called CXCR2. More recently, it has been shown that Cxcl3 regulates cell autonomously the migration of the precursors of cerebellar granule neurons toward the internal layers of cerebellum, during the morphogenesis of cerebellum. Moreover, if the expression of Cxcl3 is reduced in cerebellar granule neuron precursors, this highly enhances the frequency of the medulloblastoma, the tumor of cerebellum. In fact, the reduced expression of Cxcl3 forces the cerebellar granule neuron precursors to remain at the surface of the cerebellum, where they highly proliferate under the stimulus of Sonic hedgehog, becoming ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tumor Necrosis Factor
Tumor necrosis factor (TNF, cachexin, or cachectin; formerly known as tumor necrosis factor alpha or TNF-α) is an adipokine and a cytokine. TNF is a member of the TNF superfamily, which consists of various transmembrane proteins with a homologous TNF domain. As an adipokine, TNF promotes insulin resistance, and is associated with obesity-induced type 2 diabetes. As a cytokine, TNF is used by the immune system for cell signaling. If macrophages (certain white blood cells) detect an infection, they release TNF to alert other immune system cells as part of an inflammatory response. TNF signaling occurs through two receptors: TNFR1 and TNFR2. TNFR1 is constituitively expressed on most cell types, whereas TNFR2 is restricted primarily to endothelial, epithelial, and subsets of immune cells. TNFR1 signaling tends to be pro-inflammatory and apoptotic, whereas TNFR2 signaling is anti-inflammatory and promotes cell proliferation. Suppression of TNFR1 signaling has been important f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-6
Interleukin 6 (IL-6) is an interleukin that acts as both a pro-inflammatory cytokine and an anti-inflammatory myokine. In humans, it is encoded by the ''IL6'' gene. In addition, osteoblasts secrete IL-6 to stimulate osteoclast formation. Smooth muscle cells in the tunica media of many blood vessels also produce IL-6 as a pro-inflammatory cytokine. IL-6's role as an anti-inflammatory myokine is mediated through its inhibitory effects on TNF-alpha and IL-1 and its activation of IL-1ra and IL-10. There is some early evidence that IL-6 can be used as an inflammatory marker for severe COVID-19 infection with poor prognosis, in the context of the wider coronavirus pandemic. Function Immune system IL-6 is secreted by macrophages in response to specific microbial molecules, referred to as pathogen-associated molecular patterns ( PAMPs). These PAMPs bind to an important group of detection molecules of the innate immune system, called pattern recognition receptors (PRRs), inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-1 Beta
Interleukin-1 beta (IL-1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the ''IL1B'' gene."Catabolin" is the name given by Jeremy Saklatvala for IL-1 alpha. There are two genes for interleukin-1 (IL-1): IL-1 alpha and IL-1 beta (this gene). IL-1β precursor is cleaved by cytosolic caspase 1 (interleukin 1 beta convertase) to form mature IL-1β. Function The fever-producing property of human leukocytic pyrogen (interleukin 1) was purified by Dinarello in 1977 with a specific activity of 10–20 nanograms/kg. In 1979, Dinarello reported that purified human leukocytic pyrogen was the same molecule that was described by Igal Gery in 1972. He named it lymphocyte-activating factor (LAF) because it was a lymphocyte mitogen. It was not until 1984 that interleukin 1 was discovered to consist of two distinct proteins, now called interleukin-1 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-12
Interleukin 12 (IL-12) is an interleukin that is naturally produced by dendritic cells, macrophages, neutrophils, and human B- lymphoblastoid cells ( NC-37) in response to antigenic stimulation. IL-12 belongs to the family of interleukin-12. IL-12 family is unique in comprising the only heterodimeric cytokines, which includes IL-12, IL-23, IL-27 and IL-35. Despite sharing many structural features and molecular partners, they mediate surprisingly diverse functional effects. Gene and structure IL12 is a heterodimeric cytokine encoded by two separate genes, IL-12A (p35) and IL-12B (p40). The active heterodimer (referred to as 'p70'), and a homodimer of p40 are formed following protein synthesis. IL12A is composed of a bundle of four alpha helices. IL12B has three beta sheet domains. Functions IL-12 is involved in the differentiation of naive T cells into Th1 cells. It is known as a T cell-stimulating factor, which can stimulate the growth and function of T cells. It stimulate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytokines
Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Cytokines include chemokines, interferons, interleukins, lymphokines, and tumour necrosis factors, but generally not hormones or growth factors (despite some overlap in the terminology). Cytokines are produced by a broad range of cells, including immune cells like macrophages, B lymphocytes, T lymphocytes and mast cells, as well as endothelial cells, fibroblasts, and various stromal cells; a given cytokine may be produced by more than one type of cell. They act through cell surface receptors and are especially important in the immune system; cytokines modulate the balance between humoral and cell-based immune responses, and they regulate the maturation, growth, and resp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mincle Receptor
Macrophage inducible Ca2+-dependent lectin receptor, (abbreviated to Mincle), is a member of the C-type lectin superfamily encoded by the gene CLEC4E. It is a pattern recognition receptor that can recognize glycolipids including mycobacterial cord factor, trehalose-6,6'-dimycolate (TDM). The mincle receptor binds a range of carbohydrate structures, predominantly containing glucose or mannose, and play an important role in recognition of bacterial glycolipids by the immune system. Upon activation by cord factor, Mincle binds the Fc receptor FcRγ and Syk. Cord factor also binds and activates the related C-type lectin MCL. Upon receptor stimulation is PKC-δ activated, which subsequently phosphorylates CARD9 that triggers recruitment of BCL10 and MALT1, leading to a CARD-CC/BCL10/MALT1 (CBM) signaling complex. This signaling complex in turn triggers downstream recruitment of TRAF6 and NF-κB activation. A wide range of ligands promote signalling through Mincle, including protei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrinogen
Fibrinogen (factor I) is a glycoprotein complex, produced in the liver, that circulates in the blood of all vertebrates. During tissue and vascular injury, it is converted enzymatically by thrombin to fibrin and then to a fibrin-based blood clot. Fibrin clots function primarily to occlude blood vessels to stop bleeding. Fibrin also binds and reduces the activity of thrombin. This activity, sometimes referred to as antithrombin I, limits clotting. Fibrin also mediates blood platelet and endothelial cell spreading, tissue fibroblast proliferation, capillary tube formation, and angiogenesis and thereby promotes revascularization and wound healing. Reduced and/or dysfunctional fibrinogens occur in various congenital and acquired human fibrinogen-related disorders. These disorders represent a group of rare conditions in which individuals may present with severe episodes of pathological bleeding and thrombosis; these conditions are treated by supplementing blood fibrinogen levels an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esterified
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology The word '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
