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Foreign-body Reaction
A foreign body reaction (FBR) is a typical tissue response to a foreign body within biological tissue. It usually includes the formation of a foreign body granuloma. Tissue encapsulation of an implant is an example, as is inflammation around a splinter. Foreign body granuloma formation consists of protein adsorption, macrophages, multinucleated foreign body giant cells (macrophage fusion), fibroblasts, and angiogenesis. It has also been proposed that the mechanical property of the interface between an implant and its surrounding tissues is critical for the host response. In the long term, the foreign body reaction results in encapsulation of the foreign body within a calcified shell. For example, a ''lithopedion'' is a rare phenomenon which occurs most commonly when a fetus dies during an abdominal pregnancy, is too large to be reabsorbed by the body, and calcifies. Foreign body reaction to biomaterial implantation Following biomaterial implantation, blood and body fluids co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transvaginal Ultrasonography
Vaginal ultrasonography is a medical ultrasonography that applies an ultrasound transducer (or "probe") in the vagina to visualize organs within the pelvic cavity. It is also called transvaginal ultrasonography because the ultrasound waves go ''across'' the vaginal wall to study tissues beyond it. Uses Vaginal ultrasonography is used both as a means of gynecologic ultrasonography and obstetric ultrasonography Obstetric ultrasonography, or prenatal ultrasound, is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real-time visual images of the developing embryo or fetus in the uterus (womb). The procedure is a stand .... It is preferred over abdominal ultrasonography in the diagnosis of ectopic pregnancy. It also can be used to evaluate patients with post-menopausal bleeding. The finding on transvaginal ultrasound of a thin endometrial lining gives the physician a 99% negative predictive value that the patient does not have endometrial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Implant (medicine)
An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. For example, an implant may be a rod, used to strengthen weak bones. Medical implants are human-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In 2018, for example, American Elements developed a nickel alloy powder for 3D printing robust, long-lasting, and biocompatible medical implants. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents. Applications Implants can roughly be categorized into groups by application: Sensory and neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extravasation
Extravasation is the leakage of a fluid out of its contained space into the surrounding area, especially blood or blood cells from vessels. In the case of inflammation, it refers to the movement of white blood cells through the capillary wall, into the surrounding tissues. This is known as leukocyte extravasation, also called diapedesis. In the case of cancer metastasis, it refers to cancer cells exiting the capillaries and entering other tissues, where secondary tumors may form. The term is commonly used in a medical context. More specifically, extravasation can refer to: * Extravasation (intravenous) * Extravasation of infusates * Extravasation of irrigation fluid * Extravasation of urine * Leukocyte extravasation * Angiopellosis (non-leukocyte cell extravastion) Irrigation fluid Extravasation of irrigation fluid is the unintended migration of irrigation fluid (e.g., saline) introduced into a human body. This may occur in several types of endoscopic surgery, such as mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocyte
Monocytes are a type of leukocyte or white blood cell. They are the largest type of leukocyte in blood and can differentiate into macrophages and monocyte-derived dendritic cells. As a part of the vertebrate innate immune system monocytes also influence adaptive immune responses and exert tissue repair functions. There are at least three subclasses of monocytes in human blood based on their phenotypic receptors. Structure Monocytes are amoeboid in appearance, and have nongranulated cytoplasm. Thus they are classified as agranulocytes, although they might occasionally display some azurophil granules and/or vacuoles. With a diameter of 15–22 μm, monocytes are the largest cell type in peripheral blood. Monocytes are mononuclear cells and the ellipsoidal nucleus is often lobulated/indented, causing a bean-shaped or kidney-shaped appearance. Monocytes compose 2% to 10% of all leukocytes in the human body. Development Monocytes are produced by the bone marrow from prec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammatory Cytokine
An inflammatory cytokine or proinflammatory cytokine is a type of signaling molecule (a cytokine) that is secreted from immune cells like helper T cells (Th) and macrophages, and certain other cell types that promote inflammation. They include interleukin-1 (IL-1), IL-6, IL-12, and IL-18, tumor necrosis factor alpha (TNF-α), interferon gamma (IFNγ), and granulocyte-macrophage colony stimulating factor (GM-CSF) and play an important role in mediating the innate immune response. Inflammatory cytokines are predominantly produced by and involved in the upregulation of inflammatory reactions. Excessive chronic production of inflammatory cytokines contribute to inflammatory diseases, that have been linked to different diseases, such as atherosclerosis and cancer. Dysregulation has also been linked to depression and other neurological diseases. A balance between proinflammatory and anti-inflammatory cytokines is necessary to maintain health. Aging and exercise also play a role i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complement System
The complement system, also known as complement cascade, is a part of the humoral, innate immune system and enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen's cell membrane. Despite being part of the innate immune system, the complement system can be recruited and brought into action by antibodies generated by the adaptive immune system. The complement system consists of a number of small, inactive, liver synthesized protein precursors circulating in the blood. When stimulated by one of several triggers, proteases in the system cleave specific proteins to release cytokines and initiate an amplifying cascade of further cleavages. The end result of this ''complement activation'' or ''complement fixation'' cascade is stimulation of phagocytes to clear foreign and damaged material, inflammation to attract additional phagocytes, and activation of the cell-killi ... [...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] |
Vroman Effect
Vroman may refer to: People * Akiva Vroman, Israeli geologist * Ariel Vromen, film director * Brett Vroman, American professional basketball player *Jackson Vroman, American-Lebanese professional basketball player * Leo Vroman (1915–2014), Dutch-American hematologist and poet *Lisa Vroman Lisa Vroman (born 1956) is an American lyric soprano and stage actress. Vroman's mother and stepfather teach music, and her father was a singer. She graduated from the Crane School of Music at SUNY Potsdam in 1979. She earned a master of fin ..., American lyric soprano and stage actress * Peter Vroman, American Revolutionary War soldier Places * Vroman, Colorado, a community in the United States * Vroman, Nebraska, a community in the United States * Vroman's Nose, a prominent geological feature in Schoharie County, New York Other * Vroman's Bookstore, an independent bookstore in Southern California * Vroman effect, named after Leo Vroman See also * Frohman * Froman * Viromandui * Vroo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spontaneous Process
In thermodynamics, a spontaneous process is a process which occurs without any external input to the system. A more technical definition is the time-evolution of a system in which it releases free energy and it moves to a lower, more thermodynamically stable energy state (closer to thermodynamic equilibrium). 0 and Δ''H'' 0 and Δ''H'' > 0, the process will be spontaneous at high temperatures and non-spontaneous at low temperatures. * When Δ''S'' \left, \Delta S_\text{system}\ In many processes, the increase in entropy of the surroundings is accomplished via heat transfer from the system to the surroundings (i.e. an exothermic process). See also * Endergonic reaction reactions which are not spontaneous at standard temperature, pressure, and concentrations. * Diffusion Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Host Reactions To The Implantation Of A Biomaterial Device
A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County * Host Island, in the Wilhelm Archipelago, Antarctica People * Jim Host (born 1937), American businessman * Michel Host (1942–2021), French writer *"Host", an author abbreviation in botany for Nicolaus Thomas Host Arts, entertainment, and media Fictional entities * Hosts (''World of Darkness''), fictional characters in game ''Werewolf: The Forsaken'' *Hosts, alien invaders and overlords in the TV series ''Colony'' *Avenging Host, a group of characters in Marvel Comics' ''Earth X'' series of comic books *Rutan Host, fictional aliens from ''Doctor Who'' Film * ''Host'' (film), a 2020 horror film directed by Rob Savage Literature *''Host'', the third novel in the Rogue Mage series by Faith Hunter *''Host'', a 1993 book by Peter James * ''Hosts'' (novel), a 2001 book written by American author F. P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biocompatibility
Biocompatibility is related to the behavior of biomaterials in various contexts. The term refers to the ability of a material to perform with an appropriate host response in a specific situation. The ambiguity of the term reflects the ongoing development of insights into how biomaterials interact with the human body and eventually how those interactions determine the clinical success of a medical device (such as pacemaker, hip replacement or stent). Modern medical devices and prostheses are often made of more than one material so it might not always be sufficient to talk about the biocompatibility of a specific material. Since the immune response and repair functions in the body are so complicated it is not adequate to describe the biocompatibility of a single material in relation to a single cell type or tissue. Sometimes one hears of biocompatibility testing that is a large battery of in vitro test that is used in accordance with ISO 10993 (or other similar standards) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrosis
Fibrosis, also known as fibrotic scarring, is the development of fibrous connective tissue in response to an injury. Fibrosis can be a normal connective tissue deposition or excessive tissue deposition caused by a disease. Repeated injuries, chronic inflammation and repair are susceptible to fibrosis, where an accidental excessive accumulation of extracellular matrix components, such as the collagen, is produced by fibroblasts, leading to the formation of a permanent fibrotic scar. In response to injury, this is called scarring, and if fibrosis arises from a single cell line, this is called a fibroma. Physiologically, fibrosis acts to deposit connective tissue, which can interfere with or totally inhibit the normal architecture and function of the underlying organ or tissue. Fibrosis can be used to describe the pathological state of excess deposition of fibrous tissue, as well as the process of connective tissue deposition in healing. Defined by the pathological accumulation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
