|
Agglutination (biology)
Agglutination is the clumping of particles. The word ''agglutination'' comes from the Latin '' agglutinare'' (glueing to). Agglutination is the process that occurs if an antigen is mixed with its corresponding antibody called isoagglutinin. This term is commonly used in blood grouping. This occurs in biology in two main examples: # The clumping of cells such as bacteria or red blood cells in the presence of an antibody or complement. The antibody or other molecule binds multiple particles and joins them, creating a large complex. This increases the efficacy of microbial elimination by phagocytosis as large clumps of bacteria can be eliminated in one pass, versus the elimination of single microbial antigens. # When people are given blood transfusions of the wrong blood group, the antibodies react with the incorrectly transfused blood group and as a result, the erythrocytes clump up and stick together causing them to agglutinate. The coalescing of small particles that are suspend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agglutination In The Blood
In linguistics, agglutination is a morphological process in which words are formed by stringing together morphemes, each of which corresponds to a single syntactic feature. Languages that use agglutination widely are called agglutinative languages. Turkish is an example of an agglutinative language. The Turkish word ("from your houses") consists of the morphemes ''ev-ler-iniz-den,'' literally translated morpheme-by-morpheme as ''house-plural-your(plural)-from''. Agglutinative languages are often contrasted with isolating languages, in which words are monomorphemic, and fusional languages, in which words can be complex, but morphemes may correspond to multiple features. Examples of agglutinative languages Although agglutination is characteristic of certain language families, this does not mean that when several languages in a certain geographic area are all agglutinative they are necessarily related phylogenetically. In the past, this assumption led linguists to propose the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoagglutination
In hematology, red cell agglutination or autoagglutination is a phenomenon in which red blood cells clump together, forming aggregates. It is caused by the surface of the red cells being coated with antibodies. This often occurs in cold agglutinin disease, a type of autoimmune hemolytic anemia in which people produce antibodies (termed cold agglutinins) that bind to their red blood cells at cold temperatures and destroy them. People may develop cold agglutinins from lymphoproliferative disorders, from infection with ''Mycoplasma pneumoniae'' or Epstein–Barr virus, or idiopathically (without any apparent cause). Red cell agglutination can also occur in paroxysmal nocturnal hemoglobinuria and warm autoimmune hemolytic anemia. In cases of red cell agglutination, the direct antiglobulin test can be used to demonstrate the presence of antibodies bound to the red cells. __TOC__ Interference with laboratory tests Red blood cell aggregates are counted as single cells by the automated ana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism of coagulation involves activation, adhesion and aggregation of platelets, as well as deposition and maturation of fibrin. Coagulation begins almost instantly after an injury to the endothelium lining a blood vessel. Exposure of blood to the subendothelial space initiates two processes: changes in platelets, and the exposure of subendothelial tissue factor to plasma factor VII, which ultimately leads to cross-linked fibrin formation. Platelets immediately form a plug at the site of injury; this is called ''primary hemostasis. Secondary hemostasis'' occurs simultaneously: additional coagulation (clotting) factors beyond factor VII ( listed below) respond in a cascade to form fibrin strands, which strengthen the platelet plug. Disorders of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blocking Antibody
A blocking antibody is an antibody that does not have a reaction when combined with an antigen, but prevents other antibodies from combining with that antigen. This function of blocking antibodies has had a variety of clinical and experimental uses. The term can also be used for inhibiting antibody, prozone phenomenon and, agglutination reaction. Blocking antibodies have been described as a mechanism for HSV-1 to evade the immune system. Uses Blocking antibodies can be used in a variety of medical and scientific manners, thus far been to treat cancer, Graves' disease, and prevent the growth of malaria in mosquitoes. Cancer treatment Blocking antibodies have been used in clinical trials of cancer treatments. The blocking antibody ipilimumab has been effectively used in the clinical treatment of melanoma, RCC, and NSCLC with some degree of success. This is accomplished through the blocking of the coinhibitory molecule CTLA-4. The blocking antibody does not directly target ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agglutination-PCR
Agglutination-PCR (ADAP) is an ultrasensitive solution-phase method for detecting antibodies. Antibodies bind to and agglutinate synthetic antigen– DNA conjugates, enabling ligation of the DNA strands and subsequent quantification by qPCR. Like other Immuno-PCR (IPCR) detection methods ADAP combines the specificity of antibody-antigen recognition and the sensitivity of PCR. ADAP detects zepto- to attomoles of antibodies in 2 μL of sample with a dynamic range spanning 5–6 orders of magnitude. For example, ADAP allows to detect anti-thyroglobulin autoantibodies from human patient plasma with a 1000-fold increased sensitivity over an FDA-approved radioimmunoassay. ADAP also allows to simultaneously detect multiple antibodies in one experiment, much more than ELISA or radioimmunoassay A radioimmunoassay (RIA) is an immunoassay that uses radiolabeled molecules in a stepwise formation of immune complexes. A RIA is a very sensitive in vitro assay technique used to measure concentra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serology
Serology is the scientific study of Serum (blood), serum and other body fluids. In practice, the term usually refers to the medical diagnosis, diagnostic identification of Antibody, antibodies in the serum. Such antibodies are typically formed in response to an infection (against a given microorganism), against other foreign proteins (in response, for example, to a Acute hemolytic transfusion reaction, mismatched blood transfusion), or to one's own proteins (in instances of autoimmune disease). In either case, the procedure is simple. Serological tests Serological tests are diagnostic methods that are used to identify antibodies and antigens in a patient's sample. Serological tests may be performed to diagnose infections and autoimmune illnesses, to check if a person has immunity (medical), immunity to certain diseases, and in many other situations, such as determining an individual's blood type. Serological tests may also be used in forensic serology to investigate crime scene evid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but modern medical practice commonly uses only components of the blood, such as red blood cells, white blood cells, plasma, clotting factors and platelets. Red blood cells (RBC) contain hemoglobin, and supply the cells of the body with oxygen. White blood cells are not commonly used during transfusion, but they are part of the immune system, and also fight infections. Plasma is the "yellowish" liquid part of blood, which acts as a buffer, and contains proteins and important substances needed for the body's overall health. Platelets are involved in blood clotting, preventing the body from bleeding. Before these components were known, doctors believed that blood was homogeneous. Because of this scientific misunderstanding, many patients died b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Landsteiner
Karl Landsteiner (; 14 June 1868 – 26 June 1943) was an Austrian-born American biologist, physician, and immunologist. He distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the blood, and in 1937 identified, with Alexander S. Wiener, the Rhesus factor, thus enabling physicians to transfuse blood without endangering the patient's life. With Constantin Levaditi and Erwin Popper, he discovered the polio virus in 1909. He received the Aronson Prize in 1926. In 1930, he received the Nobel Prize in Physiology or Medicine. He was posthumously awarded the Lasker Award in 1946, and has been described as the father of transfusion medicine. Early life and education Born into a Jewish family, Landsteiner's father, Leopold (1818–1875), a renowned Viennese journalist who was editor-in-chief of ''Die Presse'', died at age 56, when Karl was only 6. This led to a close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Widal Test
The Widal test, developed in 1896 and named after its inventor, Georges-Fernand Widal, is an indirect agglutination test for enteric fever or undulant fever whereby bacteria causing typhoid fever is mixed with a serum containing specific antibodies obtained from an infected individual. In cases of ''Salmonella'' infection, it is a demonstration of the presence of O-soma false-positive result. Test results need to be interpreted carefully to account for any history of enteric fever, typhoid vaccination, and the general level of antibodies in the populations in endemic areas of the world. As with all serological tests, the rise in antibody levels needed to perform the diagnosis takes 7–14 days, which limits its applicability in early diagnosis. Other means of diagnosing ''Salmonella typhi'' (and '' paratyphi'') include cultures of blood, urine and faeces. These organisms produce H2S from thiosulfate and can be identified easily on differential media such as bismuth sulfite agar. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typhoid Fever
Typhoid fever, also known as typhoid, is a disease caused by '' Salmonella'' serotype Typhi bacteria. Symptoms vary from mild to severe, and usually begin six to 30 days after exposure. Often there is a gradual onset of a high fever over several days. This is commonly accompanied by weakness, abdominal pain, constipation, headaches, and mild vomiting. Some people develop a skin rash with rose colored spots. In severe cases, people may experience confusion. Without treatment, symptoms may last weeks or months. Diarrhea may be severe, but is uncommon. Other people may carry the bacterium without being affected, but they are still able to spread the disease. Typhoid fever is a type of enteric fever, along with paratyphoid fever. ''S. enterica'' Typhi is believed to infect and replicate only within humans. Typhoid is caused by the bacterium ''Salmonella enterica'' subsp. ''enterica'' serovar Typhi growing in the intestines, peyers patches, mesenteric lymph nodes, spleen, liver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Von Gruber
Max von Gruber (6 July 1853, in Vienna – 16 September 1927, in Berchtesgaden) was an Austrian scientist and eugenicist. As a bacteriologist he discovered specific agglutination in 1896 with his English colleague Herbert Durham (Gruber-Widal-reaction). But his main interests were studying hygiene and sexual life. Max von Gruber was the son of Ignaz Gruber (1803–1872), a general practitioner and the first specialist in otology in Austria, and publisher of a two-volume textbook on medical chemistry (1835). His brother was Franz von Gruber. He graduated from the Schottengymnasium in Vienna and studied medicine at the University of Vienna, receiving his medical doctorate in 1876. He then learned chemistry and physiology under Max von Pettenkofer (1818–1901) and Karl von Voit (1831–1908) in Munich and Karl Ludwig (1816–1895) in Leipzig. Also working under Pettenkofer was Hans Ernst August Buchner (1850–1902), who encouraged Gruber to concentrate on bacteriology. Unlike some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytohaemagglutinin
Phytohaemagglutinin (PHA, or phytohemagglutinin) is a lectin found in plants, especially certain legumes. PHA actually consists of two closely related proteins, called leucoagglutinin (PHA-L) and PHA-E. These proteins cause blood cells to clump together. PHA-E cause erythrocytes (red blood cells) to clump. PHA-L causes leukocytes (white blood cells) to clump. Phytohaemagglutinin has carbohydrate-binding specificity for a complex oligosaccharide containing galactose, ''N''-acetylglucosamine, and mannose. It is found in the highest concentrations in uncooked red kidney beans and white kidney beans (also known as cannellini), and it is also found in lower quantities in many other types of green beans and other common beans ('' Phaseolus vulgaris''), as well as broad beans (''Vicia faba'') such as fava beans. It has a number of physiological effects and is used in medical research. In high doses, it is a toxin. The lectin has a number of effects on cell metabolism; it induces mito ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
