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Calibrated Automated Thrombogram
The calibrated automated thrombogram (CAT or CT) is a thrombin generation assay (TGA) and global coagulation assay (GCA) which can be used as a coagulation test to assess thrombotic risk. It is the most widely used TGA. The CAT is a semi-automated test performed in a 96-well plate and requires specialized technologists to be performed. As a result, it has seen low implementation in routine laboratories and has been more limited to research settings. Lack of standardization with the CAT has also led to difficulties in study-to-study comparisons in research. However, efforts have recently been made towards standardization of the assay. An example of a specific commercial CAT is the Thrombinoscope by Thrombinoscope BV (now owned by Diagnostica Stago). The CAT can be used to measure thrombogram parameters such as the endogenous thrombin potential (ETP) and to assess activated protein C resistance (APCR). The CAT ETP-based APC resistance test is especially sensitive to estrogen-induce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombin Generation Assay
A thrombin generation assay (TGA) or thrombin generation test (TGT) is a global coagulation assay (GCA) and type of coagulation test which can be used to assess coagulation and thrombotic risk. It is based on the potential of a plasma to generate thrombin over time, following activation of coagulation via addition of phospholipids, tissue factor, and calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to .... The results of the TGA can be output as a thrombogram or thrombin generation curve using computer software with calculation of thrombogram parameters. TGAs can be performed with methods like the semi-automated calibrated automated thrombogram (CAT) (2003) or the fully-automated ST Genesia system (2018). TGAs were first used as manual assays in the 1950s and have since become in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Blood Tests
A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a hypodermic needle, or via fingerprick. Multiple tests for specific blood components, such as a glucose test or a cholesterol test, are often grouped together into one test panel called a blood panel or blood work. Blood tests are often used in health care to determine physiological and biochemical states, such as disease, mineral content, pharmaceutical drug effectiveness, and organ function. Typical clinical blood panels include a basic metabolic panel or a complete blood count. Blood tests are also used in drug tests to detect drug abuse. Extraction A venipuncture is useful as it is a minimally invasive way to obtain cells and extracellular fluid (plasma) from the body for analysis. Blood flows throughout the body, acting as a medium that provides oxygen and nutrients to tissues and carries waste products back to the excretory systems for disposal. Conseq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproducibility
Reproducibility, also known as replicability and repeatability, is a major principle underpinning the scientific method. For the findings of a study to be reproducible means that results obtained by an experiment or an observational study or in a statistical analysis of a data set should be achieved again with a high degree of reliability when the study is replicated. There are different kinds of replication but typically replication studies involve different researchers using the same methodology. Only after one or several such successful replications should a result be recognized as scientific knowledge. With a narrower scope, ''reproducibility'' has been introduced in computational sciences: Any results should be documented by making all data and code available in such a way that the computations can be executed again with identical results. In recent decades, there has been a rising concern that many published scientific results fail the test of reproducibility, evoking a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ST Genesia
The ST Genesia is a fully automated commercial analyzer system for performing thrombin generation assays (TGAs) and hence for coagulation testing. It was developed by Diagnostica Stago and was introduced by the company in 2018. Traditionally, TGAs has been conducted using partially automated methods like the calibrated automated thrombogram (CAT), which was introduced in 2003. However, the CAT is performed in a 96-well plate and requires specialized technologists to be performed. Consequently, it has seen low implementation in routine laboratories and has been more limited to research settings. Lack of standardization with the CAT has also led to difficulties in study-to-study comparisons in research. It has been said that the introduction of the ST Genesia system, which will allow TGAs to be performed more easily and also shows improved reproducibility Reproducibility, also known as replicability and repeatability, is a major principle underpinning the scientific method. For t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combined Oral Contraceptive
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 examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procoagulation
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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrogen (medication)
An estrogen (E) is a type of medication which is used most commonly in hormonal birth control and menopausal hormone therapy, and as part of feminizing hormone therapy for transgender women. They can also be used in the treatment of hormone-sensitive cancers like breast cancer and prostate cancer and for various other indications. Estrogens are used alone or in combination with progestogens. They are available in a wide variety of formulations and for use by many different routes of administration. Examples of estrogens include bioidentical estradiol, natural conjugated estrogens, synthetic steroidal estrogens like ethinylestradiol, and synthetic nonsteroidal estrogens like diethylstilbestrol. Estrogens are one of three types of sex hormone agonists, the others being androgens/anabolic steroids like testosterone and progestogens like progesterone. Side effects of estrogens include breast tenderness, breast enlargement, headache, nausea, fluid retention, and edema among other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
APC Resistance Test
The activated protein C resistance (APCR) test is a coagulation test used in the evaluation and diagnosis of activated protein C (APC) resistance, a form of hypercoagulability. Hereditary APC resistance is usually caused by the factor V Leiden mutation, whereas acquired APC resistance has been linked to antiphospholipid antibodies, pregnancy, and estrogen therapy. APC resistance can be measured using either an activated partial thromboplastin time (aPTT)-based test or an endogenous thrombin potential (ETP)-based test. Methodology The aPTT-based APC resistance test involves a modified aPTT test performed in the presence and absence of activated protein C (APC). The ratio of these aPTT values is calculated and is called the APC sensitivity ratio (APCsr) or simply APC ratio (APCr). This ratio is inversely related to the degree of APC resistance. The ETP-based APC resistance test involves the addition of APC to a thrombin generation assay (TGA). This results in an inhibition of throm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endogenous Thrombin Potential
A thrombin generation assay (TGA) or thrombin generation test (TGT) is a global coagulation assay (GCA) and type of coagulation test which can be used to assess coagulation and thrombotic risk. It is based on the potential of a plasma to generate thrombin over time, following activation of coagulation via addition of phospholipids, tissue factor, and calcium. The results of the TGA can be output as a thrombogram or thrombin generation curve using computer software with calculation of thrombogram parameters. TGAs can be performed with methods like the semi-automated calibrated automated thrombogram (CAT) (2003) or the fully-automated ST Genesia system (2018). TGAs were first used as manual assays in the 1950s and have since become increasingly automated. Parameters Thrombogram parameters for the TGA include: * Lag time (minutes; time until thrombin first generated/thrombin concentration first increased) * Time to peak or ttPeak (minutes; time to maximum concentration of throm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Coagulation Assay
Blood clotting tests are the tests used for diagnostics of the hemostasis system. Coagulometer is the medical laboratory analyzer used for testing of the hemostasis system. Modern coagulometers realize different methods of activation and observation of development of blood clots in blood or in blood plasma. Classification of blood clotting tests Substantially all coagulometers used in laboratory diagnostics are based on the methods of testing of the hemostasis system created more than fifty years ago. The majority of these methods are good to detect defects in one of the hemostasis components, without diagnosing other possible defects. Another problem of the actual hemostasis system diagnostics is the thrombosis prediction, i.e. sensitivity to the patient's prethrombotic state. All the diversity of clinical tests of the blood coagulation system can be divided into 2 groups: global (integral, general) tests, and «local» (specific) tests. Global tests Global tests, also known as gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombogram Parameter
A thrombin generation assay (TGA) or thrombin generation test (TGT) is a global coagulation assay (GCA) and type of coagulation test which can be used to assess coagulation and thrombotic risk. It is based on the potential of a plasma to generate thrombin over time, following activation of coagulation via addition of phospholipids, tissue factor, and calcium. The results of the TGA can be output as a thrombogram or thrombin generation curve using computer software with calculation of thrombogram parameters. TGAs can be performed with methods like the semi-automated calibrated automated thrombogram (CAT) (2003) or the fully-automated ST Genesia system (2018). TGAs were first used as manual assays in the 1950s and have since become increasingly automated. Parameters Thrombogram parameters for the TGA include: * Lag time (minutes; time until thrombin first generated/thrombin concentration first increased) * Time to peak or ttPeak (minutes; time to maximum concentration of thrombin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
