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Prothrombin Mutation
Prothrombin G20210A is a genetic condition that increases the risk of blood clots including from deep vein thrombosis, and of pulmonary embolism. One copy of the mutation increases the risk of a blood clot from 1 in 1,000 per year to 2.5 in 1,000. Two copies increases the risk to up to 20 in 1,000 per year. Most people never develop a blood clot in their lifetimes. It is due to a specific gene mutation in which a guanine (G) is changed to an adenine (A) at position 20210 of the DNA of the prothrombin gene. Other blood clotting pathway mutations that increase the risk of clots include factor V Leiden. Prothrombin G20210A was identified in the 1990s. About 2% of Caucasians carry the variant, while it is less common in other populations. It is estimated to have originated in Caucasians about 20,000 years ago. Signs and symptoms The variant causes elevated plasma prothrombin levels ( hyperprothrombinemia), possibly due to increased pre-mRNA stability. Prothrombin is the precur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Clots
A thrombus (plural thrombi), colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of cross-linked fibrin protein. The substance making up a thrombus is sometimes called cruor. A thrombus is a healthy response to injury intended to stop and prevent further bleeding, but can be harmful in thrombosis, when a clot obstructs blood flow through healthy blood vessels in the circulatory system. In the microcirculation consisting of the very small and smallest blood vessels the capillaries, tiny thrombi known as microclots can obstruct the flow of blood in the capillaries. This can cause a number of problems particularly affecting the pulmonary alveolus, alveoli in the lungs of the respiratory system resulting from reduced oxygen supply. Microclots have been found to be a characteristic feature in severe cases of COVID-19, and in lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting measurements that are expected to have some degree of error. The aim then is to use approaches from statistics to derive a pooled estimate closest to the unknown common truth based on how this error is perceived. Meta-analytic results are considered the most trustworthy source of evidence by the evidence-based medicine literature.Herrera Ortiz AF., Cadavid Camacho E, Cubillos Rojas J, Cadavid Camacho T, Zoe Guevara S, Tatiana Rincón Cuenca N, Vásquez Perdomo A, Del Castillo Herazo V, & Giraldo Malo R. A Practical Guide to Perform a Systematic Literature Review and Meta-analysis. Principles and Practice of Clinical Research. 2022;7(4):47–57. https://doi.org/10.21801/ppcrj.2021.74.6 Not only can meta-analyses provide an estimate of the un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noncoding DNA
Non-coding DNA (ncDNA) sequences are components of an organism's DNA that do not encode protein sequences. Some non-coding DNA is transcribed into functional non-coding RNA molecules (e.g. transfer RNA, microRNA, piRNA, ribosomal RNA, and regulatory RNAs). Other functional regions of the non-coding DNA fraction include regulatory sequences that control gene expression; scaffold attachment regions; origins of DNA replication; centromeres; and telomeres. Some non-coding regions appear to be mostly nonfunctional such as introns, pseudogenes, intergenic DNA, and fragments of transposons and viruses. Fraction of non-coding genomic DNA In bacteria, the coding regions typically take up 88 % of the genome. The remaining 12 % consists largely of non-coding genes and regulatory sequences, which means that almost all of the bacterial genome has a function. The amount of coding DNA in eukaryrotes is usually a much smaller fraction of the genome because eukaryotic genomes contai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F2 Gene
Thrombin (, ''fibrinogenase'', ''thrombase'', ''thrombofort'', ''topical'', ''thrombin-C'', ''tropostasin'', ''activated blood-coagulation factor II'', ''blood-coagulation factor IIa'', ''factor IIa'', ''E thrombin'', ''beta-thrombin'', ''gamma-thrombin'') is a serine protease, an enzyme that, in humans, is encoded by the ''F2'' gene. Prothrombin (coagulation factor II) is proteolytically cleaved to form thrombin in the clotting process. Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalyzing many other coagulation-related reactions. History After the description of fibrinogen and fibrin, Alexander Schmidt hypothesised the existence of an enzyme that converts fibrinogen into fibrin in 1872. Prothrombin was discovered by Pekelharing in 1894. Physiology Synthesis Thrombin is produced by the enzymatic cleavage of two sites on prothrombin by activated Factor X (Xa). The activity of factor Xa is greatl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classical Blood Coagulation Pathway
Classical may refer to: European antiquity *Classical antiquity, a period of history from roughly the 7th or 8th century B.C.E. to the 5th century C.E. centered on the Mediterranean Sea *Classical architecture, architecture derived from Greek and Roman architecture of classical antiquity *Classical mythology, the body of myths from the ancient Greeks and Romans *Classical tradition, the reception of classical Greco-Roman antiquity by later cultures * Classics, study of the language and culture of classical antiquity, particularly its literature *Classicism, a high regard for classical antiquity in the arts Music and arts *Classical ballet, the most formal of the ballet styles * Classical music, a variety of Western musical styles from the 9th century to the present * Classical guitar, a common type of acoustic guitar *Classical Hollywood cinema, a visual and sound style in the American film industry between 1927 and 1963 * Classical Indian dance, various codified art forms whose t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Testing
Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or through biochemical analysis to measure specific protein output. In a medical setting, genetic testing can be used to diagnose or rule out suspected genetic disorders, predict risks for specific conditions, or gain information that can be used to customize medical treatments based on an individual's genetic makeup. Genetic testing can also be used to determine biological relatives, such as a child's biological parentage (genetic mother and father) through DNA paternity testing, or be used to broadly predict an individual's ancestry. Genetic testing of plants and animals can be used for similar reasons as in humans (e.g. to assess relatedness/ancestry or predict/diagnose genetic disorders), to gain information used for selective breeding, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterozygous
Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism. Most eukaryotes have two matching sets of chromosomes; that is, they are diploid. Diploid organisms have the same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in a matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system. If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous, and, if both alleles are missing, it is nullizygous. The DNA sequence of a gene often varies from one individual to another. These gene variants are called alleles. While some gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combined Birth Control Pills
The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: progestin (a synthetic form of the hormone progestogen/progesterone) and estrogen (usually ethinylestradiol and 17β estradiol). When taken correctly, it alters the menstrual cycle to eliminate ovulation and prevent pregnancy. COCPs were first approved for contraceptive use in the United States in 1960, and are a very popular form of birth control. They are used by more than 100 million women worldwide and by about 9 million women in the United States. From 2015 to 2017, 12.6% of women aged 15–49 in the US reported using COCPs, making it the second most common method of contraception in this age range (female sterilization is the most common method). Use of COCPs, however, varies widely by country, age, education, and marital status. For e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticoagulation
Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time. Some of them occur naturally in blood-eating animals such as leeches and mosquitoes, where they help keep the bite area unclotted long enough for the animal to obtain some blood. As a class of medications, anticoagulants are used in therapy for thrombotic disorders. Oral anticoagulants (OACs) are taken by many people in pill or tablet form, and various intravenous anticoagulant dosage forms are used in hospitals. Some anticoagulants are used in medical equipment, such as sample tubes, blood transfusion bags, heart–lung machines, and dialysis equipment. One of the first anticoagulants, warfarin, was initially approved as a rodenticide. Anticoagulants are closely related to antiplatelet drugs and thrombolytic drugs by manipulating the various pathways of blood coagulation. Specifically, antiplatelet drugs inhibit platelet aggre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venous Ulcer
Venous ulcer is defined by the American Venous Forum as "a full-thickness defect of skin, most frequently in the ankle region, that fails to heal spontaneously and is sustained by chronic venous disease, based on venous duplex ultrasound testing." Venous ulcers are wounds that are thought to occur due to improper functioning of venous valves, usually of the legs (hence leg ulcers). They are an important cause of chronic wounds, affecting 1% of the population. Venous ulcers develop mostly along the medial distal leg, and can be painful with negative effects on quality of life. Exercise, together with compression stockings, increases healing. The NICE guideline recommends that everyone with a venous leg ulcer, even if healed, should be referred to a vascular specialist for venous duplex ultrasound and assessment for endovenous surgery. Signs and symptoms Signs and symptoms of venous ulcers include: * Moderate pain, which improves on elevation (unlike arterial ulcers which worsen w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-thrombotic Syndrome
Post-thrombotic syndrome (PTS), also called postphlebitic syndrome and venous stress disorder is a medical condition that may occur as a long-term complication of deep vein thrombosis (DVT). Signs and symptoms Signs and symptoms of PTS in the leg may include: * pain (aching or cramping) * heaviness * itching or tingling * swelling (edema) * varicose veins * brownish or reddish skin discoloration * ulcer These signs and symptoms may vary among patients and over time. With PTS, these symptoms typically are worse after walking or standing for long periods of time and improve with resting or elevating the leg. PTS lowers a person's quality of life after DVT, specifically with regards to physical and psychological symptoms and limitations in daily activities. Cause Despite outgoing research, the cause of PTS is not entirely clear. Inflammation is thought to play a role as well as damage to the venous valves from the thrombus itself. This valvular incompetence combined with persistent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Type
A blood type (also known as a blood group) is a classification of blood, based on the presence and absence of antibodies and inherited antigenic substances on the surface of red blood cells (RBCs). These antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system. Some of these antigens are also present on the surface of other types of cells of various tissues. Several of these red blood cell surface antigens can stem from one allele (or an alternative version of a gene) and collectively form a blood group system. Blood types are inherited and represent contributions from both parents of an individual. , a total of 43 human blood group systems are recognized by the International Society of Blood Transfusion (ISBT). The two most important blood group systems are ABO and Rh; they determine someone's blood type (A, B, AB, and O, with + or − denoting RhD status) for suitability in blood transfusion. Blood group systems A com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
