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Activated Protein C Resistance
Activated protein C resistance (APCR) is a hypercoagulability (an increased tendency of the blood to clot) characterized by a lack of a response to activated protein C (APC), which normally helps prevent blood from clotting excessively. This results in an increased risk of venous thrombosis (blood clots in veins), which resulting in medical conditions such as deep vein thrombosis (usually in the leg) and pulmonary embolism (in the lung, which can cause death). The most common cause of hereditary APC resistance is factor V Leiden mutation. Presentation Associated conditions An estimated 64 percent of patients with venous thromboembolism may have APC resistance. Genetics The disorder can be acquired or inherited, the hereditary form having an autosomal dominant inheritance pattern. Pathophysiology APC (with protein S as a cofactor) degrades Factor Va and Factor VIIIa. APC resistance is the inability of protein C to cleave Factor Va and/or Factor VIIIa, which allows for longer dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercoagulability
Thrombophilia (sometimes called hypercoagulability or a prothrombotic state) is an abnormality of blood coagulation that increases the risk of thrombosis (blood clots in blood vessels). Such abnormalities can be identified in 50% of people who have an episode of thrombosis (such as deep vein thrombosis in the leg) that was not provoked by other causes. A significant proportion of the population has a detectable thrombophilic abnormality, but most of these develop thrombosis only in the presence of an additional risk factor. There is no specific treatment for most thrombophilias, but recurrent episodes of thrombosis may be an indication for long-term preventive anticoagulation. The first major form of thrombophilia to be identified by medical science, antithrombin deficiency, was identified in 1965, while the most common abnormalities (including factor V Leiden) were described in the 1990s. Signs and symptoms The most common conditions associated with thrombophilia are deep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birth Control Pill
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. It is the oral form of combined hormonal contraception. The pill contains two important hormones: a progestin (a synthetic form of the hormone progestogen / progesterone) and estrogen (usually ethinylestradiol or 17β estradiol). When taken correctly, it alters the menstrual cycle to eliminate ovulation and prevent pregnancy. Combined oral contraceptive pills were first approved for contraceptive use in the United States in 1960, and remain a very popular form of birth control. They are used by more than 100 million women worldwide including about 9 million women in the United States. From 2015 to 2017, 12.6% of women aged 15–49 in the US reported using combined oral contraceptive pills, making it the second most common method of contraception in this age range ( female sterilizati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein S Deficiency
Protein S deficiency is a disorder associated with increased risk of venous thrombosis. Protein S, a vitamin K-dependent physiological anticoagulant, acts as a nonenzymatic cofactor to activate protein C in the degradation of factor Va and factor VIIIa. Decreased (antigen) levels or impaired function of protein S leads to decreased degradation of factor Va and factor VIIIa and an increased propensity to venous thrombosis. Some risk factors for deep vein thrombosis or pulmonary embolism in patients with protein S deficiency include pregnancy, older age, hormonal therapy, consumption of birth control pills, recent surgery, trauma, and physical inactivity. Protein S circulates in human plasma in two forms: approximately 60 percent is bound to complement component C4b Beta chain, β-chain while the remaining 40 percent is free, only free protein S has activated protein C cofactor activity Signs and symptoms Among the possible presentation of protein S deficiency are: Cause In terms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein C Deficiency
Protein C deficiency is a rare genetic trait that predisposes to thrombotic disease. It was first described in 1981. The disease belongs to a group of genetic disorders known as thrombophilias. Protein C deficiency is associated with an increased incidence of venous thromboembolism (relative risk 8–10), whereas no association with arterial thrombotic disease has been found. Presentation Symptoms People with a mild protein C deficiency often do not exhibit any symptoms, even into adulthood. However, they are at higher risk for venous thromboembolism, especially deep vein thrombosis. Babies with severe protein C deficiency may experience symptoms within hours or days of their birth. Some symptoms include blood clots primarily in the blood vessels of the limbs ( purpura fulminans, disseminated intravascular coagulation), abnormal bleeding into affected areas, and large purple patches or spots anywhere on the body. Complications Protein C is vitamin K-dependent. Patients with Pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antithrombin Deficiency
Antithrombin III deficiency (abbreviated ATIII deficiency) is a deficiency of antithrombin III. This deficiency may be inherited or acquired. It is a rare hereditary disorder that generally comes to light when a patient suffers recurrent venous thrombosis and pulmonary embolism, and repetitive intrauterine fetal death (IUFD). Hereditary antithrombin deficiency results in a state of increased coagulation which may lead to venous thrombosis. Inheritance is usually autosomal dominant, though a few recessive cases have been noted. The disorder was first described by Egeberg in 1965. The causes of acquired antithrombin deficiency are easier to find than the hereditary deficiency. The prevalence of antithrombin deficiency is estimated at ~0.02 to 0.2% of the general population, and 1-5% of patients with venous thromboembolism. There is an elevated risk of thrombosis, whereby 50% patients with AT deficiency were found to have venous thromboembolism by age 50. Presentation Diagnosi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombophilia
Thrombophilia (sometimes called hypercoagulability or a prothrombotic state) is an abnormality of blood coagulation that increases the risk of thrombosis (blood clots in blood vessels). Such abnormalities can be identified in 50% of people who have an episode of thrombosis (such as deep vein thrombosis in the leg) that was not provoked by other causes. A significant proportion of the population has a detectable thrombophilic abnormality, but most of these develop thrombosis only in the presence of an additional risk factor. There is no specific treatment for most thrombophilias, but recurrent episodes of thrombosis may be an indication for long-term preventive anticoagulant, anticoagulation. The first major form of thrombophilia to be identified by medical science, antithrombin deficiency, was identified in 1965, while the most common abnormalities (including factor V Leiden) were described in the 1990s. Signs and symptoms The most common conditions associated with thrombophi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homozygous
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticoagulation
An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which help keep the bite area unclotted long enough for the animal to obtain 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 aggregation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surgery
Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery such as gastric bypass), to reconstruct or alter aesthetics and appearance (cosmetic surgery), or to remove unwanted tissue (biology), tissues (body fat, glands, scars or skin tags) or foreign bodies. The act of performing surgery may be called a surgical procedure or surgical operation, or simply "surgery" or "operation". In this context, the verb "operate" means to perform surgery. The adjective surgical means pertaining to surgery; e.g. surgical instruments, operating theater, surgical facility or surgical nurse. Most surgical procedures are performed by a pair of operators: a surgeon who is the main operator performing the surgery, and a surgical assistant who provides in-procedure manual assistance during surgery. Modern surgical opera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombosis
Thrombosis () is the formation of a Thrombus, blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thrombocytes) and fibrin to form a blood clot to prevent blood loss. Even when a blood vessel is not injured, blood clots may form in the body under certain conditions. A clot, or a piece of the clot, that breaks free and begins to travel around the body is known as an embolus. Thrombosis can cause serious conditions such as stroke and heart attack. Thrombosis may occur in veins (venous thrombosis) or in arteries (arterial thrombosis). Venous thrombosis (sometimes called DVT, deep vein thrombosis) leads to a blood clot in the affected part of the body, while arterial thrombosis (and, rarely, severe venous thrombosis) affects the blood supply and leads to damage of the tissue supplied by that artery (ischemia and necrosis). A piece of either an arterial or a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Risk Factor
In epidemiology, a risk factor or determinant is a variable associated with an increased risk of disease or infection. Due to a lack of harmonization across disciplines, determinant, in its more widely accepted scientific meaning, is often used as a synonym. The main difference lies in the realm of practice: medicine (clinical practice) versus public health. As an example from clinical practice, low ingestion of dietary sources of vitamin C is a known risk factor for developing scurvy. Specific to public health policy, a determinant is a health risk that is general, abstract, related to inequalities, and difficult for an individual to control. For example, poverty is known to be a determinant of an individual's standard of health. Risk factors may be used to identify high-risk people. Correlation vs causation Risk factors or determinants are correlational and not necessarily causal, because correlation does not prove causation. For example, being young cannot be said to caus ... [...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 locus (genetics), 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#Chromosomal determination, sex-determination system. If both alleles of a diploid organism are the same, the organism is #Homozygous, homozygous at that locus. If they are different, the organism is #Heterozygous, heterozygous at that locus. If one allele is missing, it is #Hemizygous, hemizygous, and, if both alleles are missing, it is #Nullizygous, nullizygous. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
