|
Heparin
Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Since heparins depend on the activity of antithrombin, they are considered anticoagulants. Specifically it is also used in the treatment of heart attacks and unstable angina. It is given intravenously or by injection under the skin. Other uses for its anticoagulant properties include inside blood specimen test tubes and kidney dialysis machines. Common side effects include bleeding, pain at the injection site, and low blood platelets. Serious side effects include heparin-induced thrombocytopenia. Greater care is needed in those with poor kidney function. Heparin is contraindicated for suspected cases of vaccine-induced pro-thrombotic immune thrombocytopenia (VIPIT) secondary to SARS-CoV-2 vaccination, as heparin may further increase the risk of bleeding in an anti-PF4/heparin complex autoimmune manner, in favor of alternative anticoagulant medications (such as arg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heparin Structure
Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Since heparins depend on the activity of antithrombin, they are considered anticoagulants. Specifically it is also used in the treatment of heart attacks and unstable angina. It is given intravenously or by injection under the skin. Other uses for its anticoagulant properties include inside blood specimen test tubes and kidney dialysis machines. Common side effects include bleeding, pain at the injection site, and low blood platelets. Serious side effects include heparin-induced thrombocytopenia. Greater care is needed in those with poor kidney function. Heparin is contraindicated for suspected cases of vaccine-induced pro-thrombotic immune thrombocytopenia (VIPIT) secondary to SARS-CoV-2 vaccination, as heparin may further increase the risk of bleeding in an anti-PF4/heparin complex autoimmune manner, in favor of alternative anticoagulant medications (such as arga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Molecular Weight Heparin
Low-molecular-weight heparin (LMWH) is a class of anticoagulant medications. They are used in the prevention of blood clots and treatment of venous thromboembolism (deep vein thrombosis and pulmonary embolism) and in the treatment of myocardial infarction. Heparin is a naturally occurring polysaccharide that inhibits coagulation, the process that leads to thrombosis. Natural heparin consists of molecular chains of varying lengths, or molecular weights. Chains of varying molecular weights, from 5000 to over 40,000 Daltons, make up polydisperse pharmaceutical-grade heparin. LMWHs, in contrast, consist of only short chains of polysaccharide. LMWHs are defined as heparin salts having an average molecular weight of less than 8000 Da and for which at least 60% of all chains have a molecular weight less than 8000 Da. These are obtained by various methods of fractionation or depolymerisation of polymeric heparin. Heparin derived from natural sources, mainly porcine intestine or bovine l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heparin-induced Thrombocytopenia
Heparin-induced thrombocytopenia (HIT) is the development of thrombocytopenia (a low platelet count), due to the administration of various forms of heparin, an anticoagulant. HIT predisposes to thrombosis (the abnormal formation of blood clots inside a blood vessel) because platelets release microparticles that activate thrombin, thereby leading to thrombosis. When thrombosis is identified the condition is called heparin-induced thrombocytopenia and thrombosis (HITT). HIT is caused by the formation of abnormal antibodies that activate platelets. If someone receiving heparin develops new or worsening thrombosis, or if the platelet count falls, HIT can be confirmed with specific blood tests. The treatment of HIT requires stopping heparin treatment, and both protection from thrombosis and choice of an agent that will not reduce the platelet count any further. Several alternatives are available for this purpose; mainly used are danaparoid, fondaparinux, argatroban, and bivalirudin. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danaparoid
Danaparoid sodium (Orgaran) is an anticoagulant with an antithrombotic action due to inhibition of thrombin generation (TGI) by two mechanisms: indirect inactivation of Factor Xa via AT and direct inhibition of thrombin activation of Factor IX (an important feedback loop for thrombin generation). It also possesses a minor anti-thrombin activity, mediated equally via AT and Heparin Co-factor II producing a ratio of anti-Xa:IIa activity >22. euleman DG. Haemostasis 1992;22:58-65 and Ofosu FA Haemostasis 1992;22:66-72 Danaparoid is a low molecular weight heparinoid devoid of heparin. It consists of a mixture of heparan sulfate, dermatan sulfate, and chondroitin sulfate. It is chemically distinct from heparin, has different protein-binding properties because of its low degree of sulphation and low surface charge density and thus has little cross-reactivity in heparin-intolerant patients. The TGI activity, considered by Fernandes et al. hromb Haemostas 1987;57/3:286-93to provide an ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jay McLean
Jay McLean (1890 – November 14, 1957) was an American surgeon. He is most notable for his major contribution to the discovery of heparin. Early life Born in San Francisco in 1890, he was the son of a physician, John T. McLean. McLean's family lost their home and assets in the 1906 San Francisco earthquake. McLean set out to become a surgeon during his last year at Lowell High School. Following education at Lowell High School, he entered the University of California at Berkeley in 1909, obtaining his Bachelor of Science degree in 1914. Career McLean moved to Baltimore following his graduation from the University of California before receiving an acceptance from Johns Hopkins School of Medicine. Following his move he was informed of a vacancy at the school and began his medical studies in 1915. McLean entered Johns Hopkins School of Medicine in 1915 where he met and began work with physiologist William Henry Howell. Howell admitted McLean into his laboratory and assigned him ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients. A normal human platelet count ranges from 150,000 to 450,000 platelets/microliter (μl) of blood. Values outside this range do not necessarily indicate disease. One common definition of thrombocytopenia requiring emergency treatment is a platelet count below 50,000/μl. Thrombocytopenia can be contrasted with the conditions associated with an abnormally ''high'' level of platelets in the blood - thrombocythemia (when the cause is unknown), and thrombocytosis (when the cause is known). Signs and symptoms Thrombocytopenia usually has no symptoms and is picked up on a routine complete blood count. Some individuals with thrombocytopenia may experience external bleeding, such as nosebleeds or bleeding gums. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antithrombin
Antithrombin (AT) is a small glycoprotein that inactivates several enzymes of the coagulation system. It is a 432-amino-acid protein produced by the liver. It contains three disulfide bonds and a total of four possible glycosylation sites. α-Antithrombin is the dominant form of antithrombin found in blood plasma and has an oligosaccharide occupying each of its four glycosylation sites. A single glycosylation site remains consistently un-occupied in the minor form of antithrombin, β-antithrombin. Its activity is increased manyfold by the anticoagulant drug heparin, which enhances the binding of antithrombin to factor IIa (prothrombin) and factor Xa. Nomenclature Antithrombin is also termed antithrombin III (AT III). The designations antithrombin I through to antithrombin IV originate in early studies carried out in the 1950s by Seegers, Johnson and Fell. Antithrombin I (AT I) refers to the absorption of thrombin onto fibrin after thrombin has activated fibrinogen. Antithro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosaminoglycan
Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide units (i.e. two-sugar units). The repeating two-sugar unit consists of a uronic sugar and an amino sugar, except in the case of the sulfated glycosaminoglycan keratan, where, in place of the uronic sugar there is a galactose unit. GAGs are found in vertebrates, invertebrates and bacteria. Because GAGs are highly polar molecules and attract water; the body uses them as lubricants or shock absorbers. Mucopolysaccharidoses are a group of metabolic disorders in which abnormal accumulations of glycosaminoglycans occur due to enzyme deficiencies. Production Glycosaminoglycans vary greatly in molecular mass, disaccharide structure, and sulfation. This is because GAG synthesis is not template driven, as are proteins or nucleic acids, but constantly altered by processing enzymes. GAGs are classified into four groups, based on their core disaccharide structures. Hepa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Henry Howell
William Henry Howell (February 20, 1860 – February 6, 1945) was an American physiologist. He pioneered the use of heparin as a blood anti-coagulant. Early life William Henry Howell was born on February 20, 1860, in Baltimore, Maryland. He graduated from the Baltimore City College high school in 1878. He was educated at Johns Hopkins University, from which he graduated in 1881 with a Bachelor of Arts. He taught at the University of Michigan and at Harvard before becoming professor at Johns Hopkins in 1893. He received a Doctor of Medicine from the University of Michigan in 1890. He graduated with a PhD from Johns Hopkins in 1894. He also studied at Trinity College and the University of Edinburgh. Career Howell served as associate professor of physiology at Johns Hopkins in 1888 and 1889. He served as a full professor at the University of Michigan from 1889 to 1892. He then served as associate professor of physiology at Harvard Medical School from 1892 to 1893. He then moved ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erik Jorpes
Johan Erik Jorpes (born Johansson, 15 July 1894 – 10 July 1973) was a Finnish-born Swedish physician and biochemist. He identified the chemical structure of heparin and developed its clinical applications. Jorpes was the professor of medical chemistry in the Karolinska Institute in Stockholm in 1946–1963. Early life Erik Jorpes was born as Johan Erik Johansson to a poor fisherman's family in the village of Överboda in Kökar in Åland. The family lived in a house called ''Jorpes'', which he later adopted as his last name to replace the patronyme ''Johansson''. After the primary school, his parents send the talented kid to high school in Turku. Other students of the Swedish-language ''Svenska klassiska lyceum'' came mostly from wealthy upper-class families, Jorpes was bullied of his social status and dialect. As a result, Jorpes got interested in socialist ideas in the early 1910s. He joined the local Social Democratic student organization and wrote marxist articles to the ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myocardial Infarction
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often it occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn. Other symptoms may include shortness of breath, nausea, feeling faint, a cold sweat or feeling tired. About 30% of people have atypical symptoms. Women more often present without chest pain and instead have neck pain, arm pain or feel tired. Among those over 75 years old, about 5% have had an MI with little or no history of symptoms. An MI may cause heart failure, an irregular heartbeat, cardiogenic shock or cardiac arrest. Most MIs occur due to coronary artery disease. Risk factors include high blood pressure, smoking, diabetes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WHO Model List Of Essential Medicines
The WHO Model List of Essential Medicines (aka Essential Medicines List or EML), published by the World Health Organization (WHO), contains the medications considered to be most effective and safe to meet the most important needs in a health system. The list is frequently used by countries to help develop their own local lists of essential medicines. , more than 155 countries have created national lists of essential medicines based on the World Health Organization's model list. This includes both developed and developing countries. The list is divided into core items and complementary items. The core items are deemed to be the most cost-effective options for key health problems and are usable with little additional health care resources. The complementary items either require additional infrastructure such as specially trained health care providers or diagnostic equipment or have a lower cost–benefit ratio. About 25% of items are in the complementary list. Some medicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
