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Developmental Immunotoxicology
Immunotoxicology (sometimes abbreviated as ITOX) is the study of the toxicity of foreign substances called xenobiotics and their effects on the immune system. Some toxic agents that are known to alter the immune system include: industrial chemicals, heavy metals, agrochemicals, pharmaceuticals, drugs, ultraviolet radiation, air pollutants and some biological materials. The effects of these immunotoxic substances have been shown to alter both the innate and adaptive parts of the immune system. Consequences of xenobiotics affect the organ initially in contact (often the lungs or skin). Some commonly seen problems that arise as a result of contact with immunotoxic substances are: immunosuppression, hypersensitivity, and autoimmunity. The toxin-induced immune dysfunction may also increase susceptibility to cancer. The study of immunotoxicology began in the 1970s. However, the idea that some substances have a negative effect on the immune system was not a novel concept as people have ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxicity
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacteria, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (biology), cell (cytotoxicity) or an organ such as the liver (hepatotoxicity). Sometimes the word is more or less synonymous with poison#Poisoning, poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are Dose (biochemistry), dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to bypass animal testing, while maintaining the concept of toxicity endpoints. Etymology In Ancient G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin G
Immunoglobulin G (IgG) is a type of antibody. Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in blood circulation. IgG molecules are created and released by plasma B cells. Each IgG antibody has two paratopes. Function Antibodies are major components of humoral immunity. IgG is the main type of antibody found in blood and extracellular fluid, allowing it to control infection of body tissues. By binding many kinds of pathogens such as viruses, bacteria, and fungi, IgG protects the body from infection. It does this through several mechanisms: * IgG-mediated binding of pathogens causes their immobilization and binding together via agglutination; IgG coating of pathogen surfaces (known as opsonization) allows their recognition and ingestion by phagocytic immune cells leading to the elimination of the pathogen itself; * IgG activates the classical pathway of the complement system, a cascade of immune protein product ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Immunotoxicology
The ''Journal of Immunotoxicology'' is a quarterly peer-reviewed scientific journal that publishes articles in the fields of immunotoxicology, immunology, and toxicology. It is published by Informa. Aims and scope The journal publishes findings about the immunomodulating effects, as well as mechanisms of activity, of: * industrial chemicals * pharmaceuticals * environmental contaminants * food products * radiation * stressors Editor in chief and impact factor The editor in chief of the ''Journal of Immunotoxicology'' is Mitchell D. Cohen (New York University School of Medicine, Tuxedo, New York, United States. According to the ''Journal Citation Reports'' it received an impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.054, ranking it 55th out of 87 journals i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin E
Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) " isoform") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the ε chain containing four Ig-like constant domains (Cε1–Cε4). IgE is thought to be an important part of the immune response against infection by certain parasitic worms, including '' Schistosoma mansoni'', ''Trichinella spiralis'', and ''Fasciola hepatica''. IgE is also utilized during immune defense against certain protozoan parasites such as ''Plasmodium falciparum''. IgE may have evolved as a defense to protect against venoms. IgE also has an essential role in type I hypersensitivity, which manifests in various allergic diseases, such as allergic asthma, most types of sinusitis, allergic rhinitis, food allergies, and specific types of chronic urticaria and atopic dermatitis. IgE also plays a pivotal role in responses to allergens, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hapten
Haptens (derived from the Greek ''haptein'', meaning “to fasten”) are small molecules that elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself. The mechanisms of absence of immune response may vary and involve complex immunological interactions, but can include absent or insufficient co-stimulatory signals from antigen-presenting cells. Haptens have been used to study allergic contact dermatitis (ACD) and the mechanisms of inflammatory bowel disease (IBD) to induce autoimmune-like responses. The concept of haptens emerged from the work of Austrian immunologist Karl Landsteiner, who also pioneered the use of synthetic haptens to study immunochemical phenomena. Immune reaction on a hapten-carrier adduct Haptens applied on skin, when conjugate with a carrier, could induce contact hypersensitivity, which is a type IV delayed hypersensitivity reaction mediated by T cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanomaterials
Nanomaterials describe, in principle, chemical substances or materials of which a single unit is sized (in at least one dimension) between 1 and 100 nm (the usual definition of nanoscale). Nanomaterials research takes a materials science-based approach to nanotechnology, leveraging advances in materials metrology and synthesis which have been developed in support of microfabrication research. Materials with structure at the nanoscale often have unique optical, electronic, thermo-physical or mechanical properties. Nanomaterials are slowly becoming commercialized and beginning to emerge as commodities. Definition In ISO/TS 80004, ''nanomaterial'' is defined as the "material with any external dimension in the nanoscale or having internal structure or surface structure in the nanoscale", with ''nanoscale'' defined as the "length range approximately from 1 nm to 100 nm". This includes both ''nano-objects'', which are discrete pieces of material, and ''nanostructu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agranulocytosis
Agranulocytosis, also known as agranulosis or granulopenia, is an acute condition involving a severe and dangerous lowered white blood cell count (leukopenia, most commonly of neutrophils) and thus causing neutropenia in the circulating blood. It is a severe lack of one major class of infection-fighting white blood cells. People with this condition are at very high risk of serious infections due to their suppressed immune system. In agranulocytosis, the concentration of granulocytes (a major class of white blood cells that includes neutrophils, basophils, and eosinophils) drops below 200 cells/mm3 of blood. Signs and symptoms Agranulocytosis may be asymptomatic, or may clinically present with sudden fever, rigors and sore throat. Infection of any organ may be rapidly progressive (e.g., pneumonia, urinary tract infection). Sepsis may also progress rapidly. Causes A large number of drugs have been associated with agranulocytosis, including antiepileptics (such as carbamaz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regulatory T Cell
The regulatory T cells (Tregs or Treg cells), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain immune tolerance, tolerance to self-antigens, and prevent autoimmune disease. Treg cells are immunosuppression, immunosuppressive and generally suppress or downregulation and upregulation, downregulate induction and proliferation of effector T cells. Treg cells express the biomarkers CD4, FOXP3, and CD25 and are thought to be derived from the same cell lineage, lineage as naïve T helper cell, CD4+ cells. Because effector T cells also express CD4 and CD25, Treg cells are very difficult to effectively discern from effector CD4+, making them difficult to study. Research has found that the cytokine Transforming growth factor beta, transforming growth factor beta (TGF-β) is essential for Treg cells to differentiate from naïve CD4+ cells and is important in maintaining Treg cell homeostas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin M
Immunoglobulin M (IgM) is the largest of several isotypes of antibodies (also known as immunoglobulin) that are produced by vertebrates. IgM is the first antibody to appear in the response to initial exposure to an antigen; causing it to also be called an acute phase antibody. In humans and other mammals that have been studied, plasmablasts in the spleen are the main source of specific IgM production. History In 1937, an antibody was observed in horses hyper-immunized with pneumococcus polysaccharide that was much larger in size than the typical rabbit γ-globulin, with a molecular weight of 990,000 daltons. In accordance with its larger size, the new antibody was originally referred to as γ-macroglobulin, and subsequently termed IgM—M for “macro”. The V domains of normal immunoglobulin are highly heterogeneous, reflecting their role in protecting against the great variety of infectious microbes, and this heterogeneity impeded detailed structural analysis of IgM. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenobiotic
A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism. It can also cover substances that are present in much higher concentrations than are usual. Natural compounds can also become xenobiotics if they are taken up by another organism, such as the uptake of natural human hormones by fish found downstream of sewage treatment plant outfalls, or the chemical defenses produced by some organisms as protection against predators. The term "xenobiotic" is also used to refer to organs transplanted from one species to another. The term "xenobiotics", however, is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls and their effect on the biota, because xenobiotics are understood as substances foreign to an entire biological system, i.e. artificial substances, which did not exist in nature before their synthesis by humans. The term xenobiotic is derived from the Gree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involved in a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. Some common naturally occurring steroid hormones are cortisol (), corticosterone (), cortisone () and aldosterone () (cortisone and aldosterone are isomers). The main corticosteroids produced by the adrenal cortex are cortisol and aldosterone. The etymology of the '' cortico-'' part of the name refers to the adrenal cortex, which makes these steroid hormones. Thus a corticosteroid is a "cortex steroid". Classes * Glucocorticoids such as cortisol affect carbohydrate, fat, and protein metabolism, and have anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
In Vitro
''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology and its subdisciplines are traditionally done in labware such as test tubes, flasks, Petri dishes, and microtiter plates. Studies conducted using components of an organism that have been isolated from their usual biological surroundings permit a more detailed or more convenient analysis than can be done with whole organisms; however, results obtained from ''in vitro'' experiments may not fully or accurately predict the effects on a whole organism. In contrast to ''in vitro'' experiments, ''in vivo'' studies are those conducted in living organisms, including humans, known as clinical trials, and whole plants. Definition ''In vitro'' (Latin language, Latin for "in glass"; often not italicized in English usage) studies are conducted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
