One of the three polypeptide chains that make up the TROPONIN complex. It is a cardiac-specific protein that binds to TROPOMYOSIN. It is released from damaged or injured heart muscle cells (MYOCYTES, CARDIAC). Defects in the gene encoding troponin T result in FAMILIAL HYPERTROPHIC CARDIOMYOPATHY.
One of the minor protein components of skeletal muscle. Its function is to serve as the calcium-binding component in the troponin-tropomyosin B-actin-myosin complex by conferring calcium sensitivity to the cross-linked actin and myosin filaments.
One of the three polypeptide chains that make up the TROPONIN complex of skeletal muscle. It is a calcium-binding protein.
A protein found in the thin filaments of muscle fibers. It inhibits contraction of the muscle unless its position is modified by TROPONIN.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
A transferase that catalyzes formation of PHOSPHOCREATINE from ATP + CREATINE. The reaction stores ATP energy as phosphocreatine. Three cytoplasmic ISOENZYMES have been identified in human tissues: the MM type from SKELETAL MUSCLE, the MB type from myocardial tissue and the BB type from nervous tissue as well as a mitochondrial isoenzyme. Macro-creatine kinase refers to creatine kinase complexed with other serum proteins.
One of the three polypeptide chains that make up the TROPONIN complex. It inhibits F-actin-myosin interactions.
An isoenzyme of creatine kinase found in the CARDIAC MUSCLE.
The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .
Pressure, burning, or numbness in the chest.
Contractile tissue that produces movement in animals.
NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A form of CARDIAC MUSCLE disease, characterized by left and/or right ventricular hypertrophy (HYPERTROPHY, LEFT VENTRICULAR; HYPERTROPHY, RIGHT VENTRICULAR), frequent asymmetrical involvement of the HEART SEPTUM, and normal or reduced left ventricular volume. Risk factors include HYPERTENSION; AORTIC STENOSIS; and gene MUTATION; (FAMILIAL HYPERTROPHIC CARDIOMYOPATHY).
Precordial pain at rest, which may precede a MYOCARDIAL INFARCTION.
Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments.
The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.
The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.
A protein complex of actin and MYOSINS occurring in muscle. It is the essential contractile substance of muscle.
An autosomal dominant inherited form of HYPERTROPHIC CARDIOMYOPATHY. It results from any of more than 50 mutations involving genes encoding contractile proteins such as VENTRICULAR MYOSINS; cardiac TROPONIN T; ALPHA-TROPOMYOSIN.
A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.
General or unspecified injuries to the heart.
A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.
Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.
Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.
Contractile activity of the MYOCARDIUM.
A PEPTIDE that is secreted by the BRAIN and the HEART ATRIA, stored mainly in cardiac ventricular MYOCARDIUM. It can cause NATRIURESIS; DIURESIS; VASODILATION; and inhibits secretion of RENIN and ALDOSTERONE. It improves heart function. It contains 32 AMINO ACIDS.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
A disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. The decreased blood flow may be due to narrowing of the coronary arteries (CORONARY ARTERY DISEASE), to obstruction by a thrombus (CORONARY THROMBOSIS), or less commonly, to diffuse narrowing of arterioles and other small vessels within the heart. Severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle (MYOCARDIAL INFARCTION).
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The hollow, muscular organ that maintains the circulation of the blood.
A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A form of CARDIAC MUSCLE disease in which the ventricular walls are excessively rigid, impeding ventricular filling. It is marked by reduced diastolic volume of either or both ventricles but normal or nearly normal systolic function. It may be idiopathic or associated with other diseases (ENDOMYOCARDIAL FIBROSIS or AMYLOIDOSIS) causing interstitial fibrosis.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
Elements of limited time intervals, contributing to particular results or situations.
A group of diseases in which the dominant feature is the involvement of the CARDIAC MUSCLE itself. Cardiomyopathies are classified according to their predominant pathophysiological features (DILATED CARDIOMYOPATHY; HYPERTROPHIC CARDIOMYOPATHY; RESTRICTIVE CARDIOMYOPATHY) or their etiological/pathological factors (CARDIOMYOPATHY, ALCOHOLIC; ENDOCARDIAL FIBROELASTOSIS).
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
Thiadiazines are heterocyclic compounds containing a 5-membered ring made up of two nitrogen atoms and three carbon atoms, one of which is bonded to a sulfur atom, and are known for their diverse pharmacological properties, including use as anti-inflammatory, anticonvulsant, and antipsychotic agents.
An episode of MYOCARDIAL ISCHEMIA that generally lasts longer than a transient anginal episode that ultimately may lead to MYOCARDIAL INFARCTION.
A class of organic compounds that contains a naphthalene moiety linked to a sulfonic acid salt or ester.
A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
Disease having a short and relatively severe course.
A form of CARDIAC MUSCLE disease that is characterized by ventricular dilation, VENTRICULAR DYSFUNCTION, and HEART FAILURE. Risk factors include SMOKING; ALCOHOL DRINKING; HYPERTENSION; INFECTION; PREGNANCY; and mutations in the LMNA gene encoding LAMIN TYPE A, a NUCLEAR LAMINA protein.
A technique using antibodies for identifying or quantifying a substance. Usually the substance being studied serves as antigen both in antibody production and in measurement of antibody by the test substance.
Myosin type II isoforms found in cardiac muscle.
A large family of mollusks in the class BIVALVIA, known commonly as scallops. They possess flat, almost circular shells and are found in all seas from shallow water to great depths.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Pathological conditions involving the HEART including its structural and functional abnormalities.
A serine endopeptidase secreted by the pancreas as its zymogen, CHYMOTRYPSINOGEN and carried in the pancreatic juice to the duodenum where it is activated by TRYPSIN. It selectively cleaves aromatic amino acids on the carboxyl side.
The larger subunits of MYOSINS. The heavy chains have a molecular weight of about 230 kDa and each heavy chain is usually associated with a dissimilar pair of MYOSIN LIGHT CHAINS. The heavy chains possess actin-binding and ATPase activity.
A graphic means for assessing the ability of a screening test to discriminate between healthy and diseased persons; may also be used in other studies, e.g., distinguishing stimuli responses as to a faint stimuli or nonstimuli.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Parts of the myosin molecule resulting from cleavage by proteolytic enzymes (PAPAIN; TRYPSIN; or CHYMOTRYPSIN) at well-localized regions. Study of these isolated fragments helps to delineate the functional roles of different parts of myosin. Two of the most common subfragments are myosin S-1 and myosin S-2. S-1 contains the heads of the heavy chains plus the light chains and S-2 contains part of the double-stranded, alpha-helical, heavy chain tail (myosin rod).
Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.

Roles for the troponin tail domain in thin filament assembly and regulation. A deletional study of cardiac troponin T. (1/1295)

Striated muscle contraction is regulated by Ca2+ binding to troponin, which has a globular domain and an elongated tail attributable to the NH2-terminal portion of the bovine cardiac troponin T (TnT) subunit. Truncation of the bovine cardiac troponin tail was investigated using recombinant TnT fragments and subunits TnI and TnC. Progressive truncation of the troponin tail caused progressively weaker binding of troponin-tropomyosin to actin and of troponin to actin-tropomyosin. A sharp drop-off in affinity occurred with NH2-terminal deletion of 119 rather than 94 residues. Deletion of 94 residues had no effect on Ca2+-activation of the myosin subfragment 1-thin filament MgATPase rate and did not eliminate cooperative effects of Ca2+ binding. Troponin tail peptide TnT1-153 strongly promoted tropomyosin binding to actin in the absence of TnI or TnC. The results show that the anchoring function of the troponin tail involves interactions with actin as well as with tropomyosin and has comparable importance in the presence or absence of Ca2+. Residues 95-153 are particularly important for anchoring, and residues 95-119 are crucial for function or local folding. Because striated muscle regulation involves switching among the conformational states of the thin filament, regulatory significance for the troponin tail may arise from its prominent contribution to the protein-protein interactions within these conformations.  (+info)

Tissue-specific distribution of breast-muscle-type and leg-muscle-type troponin T isoforms in birds. (2/1295)

In order to show the tissue-specific distribution of troponin T (TnT) isoforms in avian skeletal muscles, their expression was examined by electrophoresis of the breast and leg muscles of seven avian species and immunoblotting with the antiserum against fast skeletal muscle TnT. It has been reported in the chicken that breast-muscle-type (B-type) and leg-muscle-type (L-type) TnT isoforms are expressed specifically in the adult breast and leg muscles, respectively. Their differential expression patterns were confirmed in all birds examined in this study. The expression of a segment encoded by the exon x series of TnT was also examined by immunoblotting with the antiserum against a synthetic peptide derived from the exon x3 sequence, because the segment has been shown to be included exclusively in the B-type, but not in the L-type TnT. The expression of the segment was found only in the breast muscle, but not in the leg muscle of all birds examined. TnT cDNA sequences from the duck breast and leg muscles were determined and showed that only B-type TnT had an exon x-related sequence, suggesting that the expression of B-type TnT containing the exon x-derived segment is conserved consistently in the birds.  (+info)

Ca2+ sensitization and potentiation of the maximum level of myofibrillar ATPase activity caused by mutations of troponin T found in familial hypertrophic cardiomyopathy. (3/1295)

Human wild-type cardiac troponin T, I, C and five troponin T mutants (I79N, R92Q, F110I, E244D, and R278C) causing familial hypertrophic cardiomyopathy were expressed in Escherichia coli, and then were purified and incorporated into rabbit cardiac myofibrils using a troponin exchange technique. The Ca2+-sensitive ATPase activity of these myofibrillar preparations was measured in order to examine the functional consequences of these troponin mutations. An I79N troponin T mutation was found to cause a definite increase in Ca2+ sensitivity of the myofibrillar ATPase activity without inducing any significant change in the maximum level of ATPase activity. A detailed analysis indicated the inhibitory action of troponin I to be impaired by the I79N troponin T mutation. Two more troponin T mutations (R92Q and R278C) were also found to have a Ca2+-sensitizing effect without inducing any change in maximum ATPase activity. Two other troponin T mutations (F110I and E244D) had no Ca2+-sensitizing effects on the ATPase activity, but remarkably potentiated the maximum level of ATPase activity. These findings indicate that hypertrophic cardiomyopathy-linked troponin T mutations have at least two different effects on the Ca2+-sensitive ATPase activity, Ca2+-sensitization and potentiation of the maximum level of the ATPase activity.  (+info)

Characterization of the cardiac holotroponin complex reconstituted from native cardiac troponin T and recombinant I and C. (4/1295)

Cardiac troponin I (cTnI), the inhibitory subunit of cardiac troponin (cTn), is phosphorylated by the cAMP-dependent protein kinase A at two adjacently located serine residues within the heart-specific N-terminal elongation. Four different phosphorylation states can be formed. To investigate each monophosphorylated form cTnI mutants, in which each of the two serine residues is replaced by an alanine, were generated. These mutants, as well as the wild-type cardiac troponin I (cTnI-WT) have been expressed in Escherichia coli, purified and characterized by isoelectric focusing, MS and CD-spectroscopy. Monophosphorylation induces conformational changes within cTnI that are different from those induced by bisphosphorylation. Functionality was assessed by measuring the calcium dependence of myosin S1 binding to thin filaments containing reconstituted native, wild-type and mutant cTn complexes. In all cases a functional holotroponin complex was obtained. Upon bisphosphorylation of cTnI-WT the pCa curve was shifted to the right to the same extent as that observed with bisphosphosphorylated native cTnI. However, the absolute values for the midpoints were higher when recombinant cTn subunits were used for reconstitution. Reconstitution itself changed the calcium affinity of cTnC: pCa50-values were higher than those obtained with the native cardiac holotroponin complex. Apparently only bisphosphorylation of cTnI influences the calcium sensitivity of the thin filament, thus monophosphorylation has a function different from that of bisphosphorylation; this function has not yet been identified.  (+info)

Diagnostic marker cooperative study for the diagnosis of myocardial infarction. (5/1295)

BACKGROUND: Millions of patients present annually with chest pain, but only 10% to 15% have myocardial infarction. Lack of diagnostic sensitivity and specificity of clinical and conventional markers prevents or delays treatment and leads to unnecessary costly admissions. Comparative data are lacking on the new markers, yet using all of them is inappropriate and expensive. METHODS AND RESULTS: The Diagnostic Marker Cooperative Study was a prospective, multicenter, double-blind study with consecutive enrollment of patients with chest pain presenting to the emergency department. Diagnostic sensitivity and specificity and frequency of increase in patients with unstable angina were determined for creatine kinase-MB (CK-MB) subforms, myoglobin, total CK-MB (activity and mass), and troponin T and I on the basis of frequent serial sampling for +info)

Effects of the prostanoid EP3-receptor agonists M&B 28767 and GR 63799X on infarct size caused by regional myocardial ischaemia in the anaesthetized rat. (6/1295)

1. This study investigates the effects of two agonists of the prostanoid EP3-receptor (M&B 28767 and GR 63799X) on the infarct size caused by regional myocardial ischaemia and reperfusion in the anaesthetized rat. 2. One hundred and sixty-seven, male Wistar rats were anaesthetized (thiopentone, 120 mg kg(-1) i.p.), ventilated (8-10 ml kg(-1), 70 strokes min(-1), inspiratory oxygen concentration: 30%; PEEP: 1-2 mmHg) and subjected to occlusion of the left anterior descending coronary artery (LAD, for 7.5, 15, 25, 35, 45 or 60 min) followed by reperfusion (2 h). Infarct size was determined by staining of viable myocardium with a tetrazolium stain (NBT), histological evaluation by light and electron microscopy and determination of the plasma levels of cardiac troponin T. 3. M&B 28767 (0.5 microg kg(-1) min(-1), i.v., n=7) or GR 63799X (3 microg kg(-1) min(-1), i.v., n=7) caused significant reductions in infarct size from 60+/-3% (25 min ischaemia and 2 h reperfusion; saline-control, n=8) to 39+/-6 and 38+/-4% of the area at risk, without causing a significant fall in blood pressure. Pretreatment of rats with 5-hydroxydecanoate (5-HD), an inhibitor of ATP-sensitive potassium channels, attenuated the cardioprotective effects of both EP3-receptor agonists. The reduction in infarct size afforded by M&B 28767 was also abolished by glibenclamide and the protein kinase C (PKC) inhibitors staurosporine and chelerythrine. 4. Thus, M&B 28767 and GR 63799X reduce myocardial infarct size in the rat by a mechanism(s) which involves the activation of PKC and the opening of ATP-sensitive potassium channels.  (+info)

Intraoperative cardiac troponin T release and lactate metabolism during coronary artery surgery: comparison of beating heart with conventional coronary artery surgery with cardiopulmonary bypass. (7/1295)

OBJECTIVE: To compare cardiac troponin T release and lactate metabolism in coronary sinus and arterial blood during uncomplicated coronary grafting on the beating heart with conventional coronary grafting using cardiopulmonary bypass. DESIGN: A prospective observational study with simultaneous sampling of coronary sinus and arterial blood: before and 1, 4, 10, and 20 minutes after reperfusion for analysis of cardiac troponin T and lactate. Cardiac troponin T was also analysed in venous samples taken 3, 6, 24, 48, and 72 hours after surgery. SETTING: Cardiac surgical unit in a tertiary referral centre. PATIENTS: 18 patients undergoing coronary grafting on the beating heart (10 single vessel and eight two-vessel grafting) and eight undergoing two-vessel grafting with cardiopulmonary bypass. RESULTS: Cardiac troponin T was detected in coronary sinus blood in all patients by 20 minutes after beating heart coronary artery surgery before arterial concentrations were consistently increased. Peak arterial and coronary sinus cardiac troponin T values on the beating heart during single (0.03 (0 to 0. 05) and 0.09 (0.07 to 0.16 microg/l, respectively) and two-vessel grafting (0.1 (0.07 to 0.11) and 0.19 (0.14 to 0.25) microg/l) were lower than the values obtained during cardiopulmonary bypass (0.64 (0.52 to 0.72) and 1.4 (0.9 to 2.0) microg/l) (p < 0.05). The area under the curve of venous cardiac troponin T over 72 hours for two-vessel grafting on the beating heart was less than with cardiopulmonary bypass (13 (10 to 16) v 68 (26 to 102) microg.h/l) (p < 0.001). Lactate extraction began within one minute of snare release during beating heart coronary surgery while lactate was still being produced 20 minutes after cross clamp release following cardiopulmonary bypass. CONCLUSIONS: Lower intraoperative and serial venous cardiac troponin T concentrations suggest a lesser degree of myocyte injury during beating heart coronary artery surgery than during cardiopulmonary bypass. Oxidative metabolism also recovers more rapidly with beating heart coronary artery surgery than with conventional coronary grafting. Coronary sinus cardiac troponin T concentrations increased earlier and were greater than arterial concentrations during beating heart surgery, suggesting that this may be a more sensitive method of intraoperative assessment of myocardial injury.  (+info)

Increasing levels of interleukin (IL)-1Ra and IL-6 during the first 2 days of hospitalization in unstable angina are associated with increased risk of in-hospital coronary events. (8/1295)

BACKGROUND: A growing body of evidence suggests a role for inflammation in acute coronary syndromes. The aim of this study was to assess the role of proinflammatory cytokines, their time course, and their association with prognosis in unstable angina. METHODS AND RESULTS: We studied 43 patients aged 62+/-8 years admitted to our coronary care unit for Braunwald class IIIB unstable angina. In each patient, serum levels of interleukin-1 receptor antagonist (IL-1Ra), interleukin-6 (IL-6) (which represent sensitive markers of biologically active IL-1beta and tumor necrosis factor-alpha levels, respectively), and troponin T were measured at entry and 48 hours after admission. Troponin T-positive patients were excluded. Patients were divided a posteriori into 2 groups according to their in-hospital outcome: group 1 comprised 17 patients with an uneventful course, and group 2 comprised 26 patients with a complicated in-hospital course. In group 1, mean IL-1Ra decreased at 48 hours by 12%, and IL-6 diminished at 48 hours by 13%. In group 2, IL-1Ra and IL-6 entry levels were higher than in group 1 and increased respectively by 37% and 57% at 48 hours (P<0.01). CONCLUSIONS: These findings indicate that although they receive the same medical therapy as patients who do not experience an in-hospital event, patients with unstable angina and with complicated in-hospital courses have higher cytokine levels on admission. A fall in IL-1Ra and IL-6 48 hours after admission was associated with an uneventful course and their increase with a complicated hospital course. These findings may suggest novel therapeutic approaches to patients with unstable angina.  (+info)

Troponin T is a subunit of the troponin complex, which is a protein complex that plays a crucial role in muscle contraction. In particular, Troponin T is responsible for binding the troponin complex to tropomyosin, another protein that helps regulate muscle contraction.

In the context of medical diagnostics, Troponin T is often measured as a biomarker for heart damage. When heart muscle cells are damaged or die, such as in a myocardial infarction (heart attack), troponin T is released into the bloodstream. Therefore, measuring the levels of Troponin T in the blood can help diagnose and assess the severity of heart damage.

It's important to note that Troponin T is specific to cardiac muscle cells, which makes it a more reliable biomarker for heart damage than other markers that may also be found in skeletal muscle cells. However, it's worth noting that Troponin T levels can also be elevated in conditions other than heart attacks, such as heart failure, myocarditis, and pulmonary embolism, so clinical context is important when interpreting test results.

Troponin is a protein complex found in cardiac and skeletal muscle cells that plays a critical role in muscle contraction. It consists of three subunits: troponin C, which binds calcium ions; troponin I, which inhibits the interaction between actin and myosin in the absence of calcium; and troponin T, which binds to tropomyosin and helps anchor the complex to the muscle filament.

In clinical medicine, "troponin" usually refers to cardiac-specific isoforms of these proteins (cTnI and cTnT) that are released into the bloodstream following damage to the heart muscle, such as occurs in myocardial infarction (heart attack). Measurement of troponin levels in the blood is a sensitive and specific biomarker for the diagnosis of acute myocardial infarction.

Troponin C is a subunit of the troponin complex, which is a protein complex that plays a crucial role in muscle contraction. In the heart, the troponin complex is found in the myofibrils of cardiac muscle cells (cardiomyocytes). It is composed of three subunits: troponin C, troponin T, and troponin I.

Troponin C has the ability to bind calcium ions (Ca²+), which is essential for muscle contraction. When Ca²+ binds to troponin C, it causes a conformational change that leads to the exposure of binding sites on troponin I for another protein called actin. This interaction allows for the cross-bridge formation between actin and myosin, generating the force needed for muscle contraction.

In clinical settings, cardiac troponins (including troponin T and troponin I) are commonly measured in blood tests to diagnose and monitor heart damage, particularly in conditions like myocardial infarction (heart attack). However, Troponin C is not typically used as a biomarker for heart injury because it is less specific to the heart than troponin T and troponin I. Increased levels of Troponin C in the blood can be found in various conditions involving muscle damage or disease, making it less useful for diagnosing heart-specific issues.

Tropomyosin is a protein that plays a crucial role in muscle contraction. It is a long, thin filamentous protein that runs along the length of actin filaments in muscle cells, forming part of the troponin-tropomyosin complex. This complex regulates the interaction between actin and myosin, which are the other two key proteins involved in muscle contraction.

In a relaxed muscle, tropomyosin blocks the myosin-binding sites on actin, preventing muscle contraction from occurring. When a signal is received to contract, calcium ions are released into the muscle cell, which binds to troponin and causes a conformational change that moves tropomyosin out of the way, exposing the myosin-binding sites on actin. This allows myosin to bind to actin and generate force, leading to muscle contraction.

Tropomyosin is composed of two alpha-helical chains that wind around each other in a coiled-coil structure. There are several isoforms of tropomyosin found in different types of muscle cells, including skeletal, cardiac, and smooth muscle. Mutations in the genes encoding tropomyosin have been associated with various inherited muscle disorders, such as hypertrophic cardiomyopathy and distal arthrogryposis.

The myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.

The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.

Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.

A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.

In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:

1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.

It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.

Creatine kinase (CK) is a muscle enzyme that is normally present in small amounts in the blood. It is primarily found in tissues that require a lot of energy, such as the heart, brain, and skeletal muscles. When these tissues are damaged or injured, CK is released into the bloodstream, causing the levels to rise.

Creatine kinase exists in several forms, known as isoenzymes, which can be measured in the blood to help identify the location of tissue damage. The three main isoenzymes are:

1. CK-MM: Found primarily in skeletal muscle
2. CK-MB: Found primarily in heart muscle
3. CK-BB: Found primarily in the brain

Elevated levels of creatine kinase, particularly CK-MB, can indicate damage to the heart muscle, such as occurs with a heart attack. Similarly, elevated levels of CK-BB may suggest brain injury or disease. Overall, measuring creatine kinase levels is a useful diagnostic tool for assessing tissue damage and determining the severity of injuries or illnesses.

Troponin I is a protein that is found in the cardiac muscle cells (myocytes) of the heart. It is a component of the troponin complex, which also includes troponin C and troponin T, that regulates the calcium-mediated interaction between actin and myosin filaments during muscle contraction.

Troponin I is specific to the cardiac muscle tissue, making it a useful biomarker for detecting damage to the heart muscle. When there is injury or damage to the heart muscle cells, such as during a heart attack (myocardial infarction), troponin I is released into the bloodstream.

Measurement of cardiac troponin I levels in the blood is used in the diagnosis and management of acute coronary syndrome (ACS) and other conditions that cause damage to the heart muscle. Elevated levels of troponin I in the blood are indicative of myocardial injury, and the degree of elevation can help determine the severity of the injury.

Creatine kinase (CK) is an enzyme found in various cells throughout the body, including heart muscle cells and skeletal muscle fibers. The CK enzyme exists in different forms, depending on the type of tissue where it is found. One such form is creatine kinase MB (CK-MB), which is primarily found in cardiac muscle cells.

An increase in the levels of CK-MB in the blood can indicate damage to the heart muscle, such as that caused by a heart attack or myocardial infarction. When heart muscle cells are damaged, they release their contents, including CK-MB, into the bloodstream. Therefore, measuring CK-MB levels is a useful diagnostic tool for detecting and monitoring heart muscle damage.

It's important to note that while an elevated CK-MB level can suggest heart muscle damage, it is not specific to the heart and can also be elevated in other conditions such as skeletal muscle damage or certain muscle disorders. Therefore, CK-MB levels should be interpreted in conjunction with other clinical findings and diagnostic tests.

Myofibrils are the basic contractile units of muscle fibers, composed of highly organized arrays of thick and thin filaments. They are responsible for generating the force necessary for muscle contraction. The thick filaments are primarily made up of the protein myosin, while the thin filaments are mainly composed of actin. Myofibrils are surrounded by a membrane called the sarcolemma and are organized into repeating sections called sarcomeres, which are the functional units of muscle contraction.

Chest pain is a discomfort or pain that you feel in the chest area. The pain can be sharp, dull, burning, crushing, heaviness, or tightness. It may be accompanied by other symptoms such as shortness of breath, sweating, nausea, dizziness, or pain that radiates to the arm, neck, jaw, or back.

Chest pain can have many possible causes, including heart-related conditions such as angina or a heart attack, lung conditions such as pneumonia or pleurisy, gastrointestinal problems such as acid reflux or gastritis, musculoskeletal issues such as costochondritis or muscle strain, and anxiety or panic attacks.

It is important to seek immediate medical attention if you experience chest pain that is severe, persistent, or accompanied by other concerning symptoms, as it may be a sign of a serious medical condition. A healthcare professional can evaluate your symptoms, perform tests, and provide appropriate treatment.

A muscle is a soft tissue in our body that contracts to produce force and motion. It is composed mainly of specialized cells called muscle fibers, which are bound together by connective tissue. There are three types of muscles: skeletal (voluntary), smooth (involuntary), and cardiac. Skeletal muscles attach to bones and help in movement, while smooth muscles are found within the walls of organs and blood vessels, helping with functions like digestion and circulation. Cardiac muscle is the specific type that makes up the heart, allowing it to pump blood throughout the body.

Myocardial infarction (MI), also known as a heart attack, is a medical condition characterized by the death of a segment of heart muscle (myocardium) due to the interruption of its blood supply. This interruption is most commonly caused by the blockage of a coronary artery by a blood clot formed on the top of an atherosclerotic plaque, which is a buildup of cholesterol and other substances in the inner lining of the artery.

The lack of oxygen and nutrients supply to the heart muscle tissue results in damage or death of the cardiac cells, causing the affected area to become necrotic. The extent and severity of the MI depend on the size of the affected area, the duration of the occlusion, and the presence of collateral circulation.

Symptoms of a myocardial infarction may include chest pain or discomfort, shortness of breath, nausea, lightheadedness, and sweating. Immediate medical attention is necessary to restore blood flow to the affected area and prevent further damage to the heart muscle. Treatment options for MI include medications, such as thrombolytics, antiplatelet agents, and pain relievers, as well as procedures such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG).

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Hypertrophic cardiomyopathy (HCM) is a genetic disorder characterized by the thickening of the heart muscle, specifically the ventricles (the lower chambers of the heart that pump blood out to the body). This thickening can make it harder for the heart to pump blood effectively, which can lead to symptoms such as shortness of breath, chest pain, and fatigue. In some cases, HCM can also cause abnormal heart rhythms (arrhythmias) and may increase the risk of sudden cardiac death.

The thickening of the heart muscle in HCM is caused by an overgrowth of the cells that make up the heart muscle, known as cardiomyocytes. This overgrowth can be caused by mutations in any one of several genes that encode proteins involved in the structure and function of the heart muscle. These genetic mutations are usually inherited from a parent, but they can also occur spontaneously in an individual with no family history of the disorder.

HCM is typically diagnosed using echocardiography (a type of ultrasound that uses sound waves to create images of the heart) and other diagnostic tests such as electrocardiogram (ECG) and cardiac magnetic resonance imaging (MRI). Treatment for HCM may include medications to help manage symptoms, lifestyle modifications, and in some cases, surgical procedures or implantable devices to help prevent or treat arrhythmias.

Unstable angina is a term used in cardiology to describe chest pain or discomfort that occurs suddenly and unexpectedly, often at rest or with minimal physical exertion. It is caused by an insufficient supply of oxygen-rich blood to the heart muscle due to reduced blood flow, typically as a result of partial or complete blockage of the coronary arteries.

Unlike stable angina, which tends to occur predictably during physical activity and can be relieved with rest or nitroglycerin, unstable angina is more severe, unpredictable, and may not respond to traditional treatments. It is considered a medical emergency because it can be a sign of an impending heart attack or other serious cardiac event.

Unstable angina is often treated in the hospital with medications such as nitroglycerin, beta blockers, calcium channel blockers, and antiplatelet agents to improve blood flow to the heart and prevent further complications. In some cases, more invasive treatments such as coronary angioplasty or bypass surgery may be necessary to restore blood flow to the affected areas of the heart.

The actin cytoskeleton is a complex, dynamic network of filamentous (threadlike) proteins that provides structural support and shape to cells, allows for cell movement and division, and plays a role in intracellular transport. Actin filaments are composed of actin monomers that polymerize to form long, thin fibers. These filaments can be organized into different structures, such as stress fibers, which provide tension and support, or lamellipodia and filopodia, which are involved in cell motility. The actin cytoskeleton is constantly remodeling in response to various intracellular and extracellular signals, allowing for changes in cell shape and behavior.

A sarcomere is the basic contractile unit in a muscle fiber, and it's responsible for generating the force necessary for muscle contraction. It is composed of several proteins, including actin and myosin, which slide past each other to shorten the sarcomere during contraction. The sarcomere extends from one Z-line to the next in a muscle fiber, and it is delimited by the Z-discs where actin filaments are anchored. Sarcomeres play a crucial role in the functioning of skeletal, cardiac, and smooth muscles.

Muscle proteins are a type of protein that are found in muscle tissue and are responsible for providing structure, strength, and functionality to muscles. The two major types of muscle proteins are:

1. Contractile proteins: These include actin and myosin, which are responsible for the contraction and relaxation of muscles. They work together to cause muscle movement by sliding along each other and shortening the muscle fibers.
2. Structural proteins: These include titin, nebulin, and desmin, which provide structural support and stability to muscle fibers. Titin is the largest protein in the human body and acts as a molecular spring that helps maintain the integrity of the sarcomere (the basic unit of muscle contraction). Nebulin helps regulate the length of the sarcomere, while desmin forms a network of filaments that connects adjacent muscle fibers together.

Overall, muscle proteins play a critical role in maintaining muscle health and function, and their dysregulation can lead to various muscle-related disorders such as muscular dystrophy, myopathies, and sarcopenia.

Actomyosin is a contractile protein complex that consists of actin and myosin filaments. It plays an essential role in muscle contraction, cell motility, and cytokinesis (the process of cell division where the cytoplasm is divided into two daughter cells). The interaction between actin and myosin generates force and movement through a mechanism called sliding filament theory. In this process, myosin heads bind to actin filaments and then undergo a power stroke, which results in the sliding of one filament relative to the other and ultimately leads to muscle contraction or cellular movements. Actomyosin complexes are also involved in various non-muscle cellular processes such as cytoplasmic streaming, intracellular transport, and maintenance of cell shape.

Hypertrophic Cardiomyopathy, Familial is a genetic disorder characterized by thickening of the heart muscle (myocardium), specifically the ventricles. This thickening, or hypertrophy, can make it harder for the heart to pump blood effectively, potentially leading to symptoms such as shortness of breath, chest pain, and arrhythmias.

In familial hypertrophic cardiomyopathy, the disorder is inherited and passed down through families in an autosomal dominant pattern, meaning that a child has a 50% chance of inheriting the gene mutation from an affected parent. The condition can vary in severity even within the same family, and some individuals with the genetic mutation may not develop symptoms at all.

It is important to note that while hypertrophic cardiomyopathy can have serious consequences, many people with the condition lead normal lives with appropriate medical management and monitoring.

Myosins are a large family of motor proteins that play a crucial role in various cellular processes, including muscle contraction and intracellular transport. They consist of heavy chains, which contain the motor domain responsible for generating force and motion, and light chains, which regulate the activity of the myosin. Based on their structural and functional differences, myosins are classified into over 35 classes, with classes II, V, and VI being the most well-studied.

Class II myosins, also known as conventional myosins, are responsible for muscle contraction in skeletal, cardiac, and smooth muscles. They form filaments called thick filaments, which interact with actin filaments to generate force and movement during muscle contraction.

Class V myosins, also known as unconventional myosins, are involved in intracellular transport and organelle positioning. They have a long tail that can bind to various cargoes, such as vesicles, mitochondria, and nuclei, and a motor domain that moves along actin filaments to transport the cargoes to their destinations.

Class VI myosins are also unconventional myosins involved in intracellular transport and organelle positioning. They have two heads connected by a coiled-coil tail, which can bind to various cargoes. Class VI myosins move along actin filaments in a unique hand-over-hand motion, allowing them to transport their cargoes efficiently.

Overall, myosins are essential for many cellular functions and have been implicated in various diseases, including cardiovascular diseases, neurological disorders, and cancer.

Heart injuries, also known as cardiac injuries, refer to any damage or harm caused to the heart muscle, valves, or surrounding structures. This can result from various causes such as blunt trauma (e.g., car accidents, falls), penetrating trauma (e.g., gunshot wounds, stabbing), or medical conditions like heart attacks (myocardial infarction) and infections (e.g., myocarditis, endocarditis).

Some common types of heart injuries include:

1. Contusions: Bruising of the heart muscle due to blunt trauma.
2. Myocardial infarctions: Damage to the heart muscle caused by insufficient blood supply, often due to blocked coronary arteries.
3. Cardiac rupture: A rare but life-threatening condition where the heart muscle tears or breaks open, usually resulting from severe trauma or complications from a myocardial infarction.
4. Valvular damage: Disruption of the heart valves' function due to injury or infection, leading to leakage (regurgitation) or narrowing (stenosis).
5. Pericardial injuries: Damage to the pericardium, the sac surrounding the heart, which can result in fluid accumulation (pericardial effusion), inflammation (pericarditis), or tamponade (compression of the heart by excess fluid).
6. Arrhythmias: Irregular heart rhythms caused by damage to the heart's electrical conduction system.

Timely diagnosis and appropriate treatment are crucial for managing heart injuries, as they can lead to severe complications or even be fatal if left untreated.

Myoglobin is a protein found in the muscle tissue, particularly in red or skeletal muscles. It belongs to the globin family and has a similar structure to hemoglobin, another oxygen-binding protein found in red blood cells. Myoglobin's primary function is to store oxygen within the muscle cells, making it readily available for use during periods of increased oxygen demand, such as during physical exertion.

Myoglobin contains heme groups that bind to and release oxygen molecules. The protein has a higher affinity for oxygen than hemoglobin, allowing it to maintain its bound oxygen even in low-oxygen environments. When muscle cells are damaged or undergo necrosis (cell death), myoglobin is released into the bloodstream and can be detected in serum or urine samples. Elevated levels of myoglobin in the blood or urine may indicate muscle injury, trauma, or diseases affecting muscle integrity, such as rhabdomyolysis or muscular dystrophies.

"Chickens" is a common term used to refer to the domesticated bird, Gallus gallus domesticus, which is widely raised for its eggs and meat. However, in medical terms, "chickens" is not a standard term with a specific definition. If you have any specific medical concern or question related to chickens, such as food safety or allergies, please provide more details so I can give a more accurate answer.

Electrocardiography (ECG or EKG) is a medical procedure that records the electrical activity of the heart. It provides a graphic representation of the electrical changes that occur during each heartbeat. The resulting tracing, called an electrocardiogram, can reveal information about the heart's rate and rhythm, as well as any damage to its cells or abnormalities in its conduction system.

During an ECG, small electrodes are placed on the skin of the chest, arms, and legs. These electrodes detect the electrical signals produced by the heart and transmit them to a machine that amplifies and records them. The procedure is non-invasive, painless, and quick, usually taking only a few minutes.

ECGs are commonly used to diagnose and monitor various heart conditions, including arrhythmias, coronary artery disease, heart attacks, and electrolyte imbalances. They can also be used to evaluate the effectiveness of certain medications or treatments.

Myocardial contraction refers to the rhythmic and forceful shortening of heart muscle cells (myocytes) in the myocardium, which is the muscular wall of the heart. This process is initiated by electrical signals generated by the sinoatrial node, causing a wave of depolarization that spreads throughout the heart.

During myocardial contraction, calcium ions flow into the myocytes, triggering the interaction between actin and myosin filaments, which are the contractile proteins in the muscle cells. This interaction causes the myofilaments to slide past each other, resulting in the shortening of the sarcomeres (the functional units of muscle contraction) and ultimately leading to the contraction of the heart muscle.

Myocardial contraction is essential for pumping blood throughout the body and maintaining adequate circulation to vital organs. Any impairment in myocardial contractility can lead to various cardiac disorders, such as heart failure, cardiomyopathy, and arrhythmias.

Brain Natriuretic Peptide (BNP) is a type of natriuretic peptide that is primarily produced in the heart, particularly in the ventricles. Although it was initially identified in the brain, hence its name, it is now known that the cardiac ventricles are the main source of BNP in the body.

BNP is released into the bloodstream in response to increased stretching or distension of the heart muscle cells due to conditions such as heart failure, hypertension, and myocardial infarction (heart attack). Once released, BNP binds to specific receptors in the kidneys, causing an increase in urine production and excretion of sodium, which helps reduce fluid volume and decrease the workload on the heart.

BNP also acts as a hormone that regulates various physiological functions, including blood pressure, cardiac remodeling, and inflammation. Measuring BNP levels in the blood is a useful diagnostic tool for detecting and monitoring heart failure, as higher levels of BNP are associated with more severe heart dysfunction.

A peptide fragment is a short chain of amino acids that is derived from a larger peptide or protein through various biological or chemical processes. These fragments can result from the natural breakdown of proteins in the body during regular physiological processes, such as digestion, or they can be produced experimentally in a laboratory setting for research or therapeutic purposes.

Peptide fragments are often used in research to map the structure and function of larger peptides and proteins, as well as to study their interactions with other molecules. In some cases, peptide fragments may also have biological activity of their own and can be developed into drugs or diagnostic tools. For example, certain peptide fragments derived from hormones or neurotransmitters may bind to receptors in the body and mimic or block the effects of the full-length molecule.

Skeletal muscle, also known as striated or voluntary muscle, is a type of muscle that is attached to bones by tendons or aponeuroses and functions to produce movements and support the posture of the body. It is composed of long, multinucleated fibers that are arranged in parallel bundles and are characterized by alternating light and dark bands, giving them a striped appearance under a microscope. Skeletal muscle is under voluntary control, meaning that it is consciously activated through signals from the nervous system. It is responsible for activities such as walking, running, jumping, and lifting objects.

The Predictive Value of Tests, specifically the Positive Predictive Value (PPV) and Negative Predictive Value (NPV), are measures used in diagnostic tests to determine the probability that a positive or negative test result is correct.

Positive Predictive Value (PPV) is the proportion of patients with a positive test result who actually have the disease. It is calculated as the number of true positives divided by the total number of positive results (true positives + false positives). A higher PPV indicates that a positive test result is more likely to be a true positive, and therefore the disease is more likely to be present.

Negative Predictive Value (NPV) is the proportion of patients with a negative test result who do not have the disease. It is calculated as the number of true negatives divided by the total number of negative results (true negatives + false negatives). A higher NPV indicates that a negative test result is more likely to be a true negative, and therefore the disease is less likely to be present.

The predictive value of tests depends on the prevalence of the disease in the population being tested, as well as the sensitivity and specificity of the test. A test with high sensitivity and specificity will generally have higher predictive values than a test with low sensitivity and specificity. However, even a highly sensitive and specific test can have low predictive values if the prevalence of the disease is low in the population being tested.

Myocardial ischemia is a condition in which the blood supply to the heart muscle (myocardium) is reduced or blocked, leading to insufficient oxygen delivery and potential damage to the heart tissue. This reduction in blood flow typically results from the buildup of fatty deposits, called plaques, in the coronary arteries that supply the heart with oxygen-rich blood. The plaques can rupture or become unstable, causing the formation of blood clots that obstruct the artery and limit blood flow.

Myocardial ischemia may manifest as chest pain (angina pectoris), shortness of breath, fatigue, or irregular heartbeats (arrhythmias). In severe cases, it can lead to myocardial infarction (heart attack) if the oxygen supply is significantly reduced or cut off completely, causing permanent damage or death of the heart muscle. Early diagnosis and treatment of myocardial ischemia are crucial for preventing further complications and improving patient outcomes.

Sensitivity and specificity are statistical measures used to describe the performance of a diagnostic test or screening tool in identifying true positive and true negative results.

* Sensitivity refers to the proportion of people who have a particular condition (true positives) who are correctly identified by the test. It is also known as the "true positive rate" or "recall." A highly sensitive test will identify most or all of the people with the condition, but may also produce more false positives.
* Specificity refers to the proportion of people who do not have a particular condition (true negatives) who are correctly identified by the test. It is also known as the "true negative rate." A highly specific test will identify most or all of the people without the condition, but may also produce more false negatives.

In medical testing, both sensitivity and specificity are important considerations when evaluating a diagnostic test. High sensitivity is desirable for screening tests that aim to identify as many cases of a condition as possible, while high specificity is desirable for confirmatory tests that aim to rule out the condition in people who do not have it.

It's worth noting that sensitivity and specificity are often influenced by factors such as the prevalence of the condition in the population being tested, the threshold used to define a positive result, and the reliability and validity of the test itself. Therefore, it's important to consider these factors when interpreting the results of a diagnostic test.

In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.

Prognosis is a medical term that refers to the prediction of the likely outcome or course of a disease, including the chances of recovery or recurrence, based on the patient's symptoms, medical history, physical examination, and diagnostic tests. It is an important aspect of clinical decision-making and patient communication, as it helps doctors and patients make informed decisions about treatment options, set realistic expectations, and plan for future care.

Prognosis can be expressed in various ways, such as percentages, categories (e.g., good, fair, poor), or survival rates, depending on the nature of the disease and the available evidence. However, it is important to note that prognosis is not an exact science and may vary depending on individual factors, such as age, overall health status, and response to treatment. Therefore, it should be used as a guide rather than a definitive forecast.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

Actin is a type of protein that forms part of the contractile apparatus in muscle cells, and is also found in various other cell types. It is a globular protein that polymerizes to form long filaments, which are important for many cellular processes such as cell division, cell motility, and the maintenance of cell shape. In muscle cells, actin filaments interact with another type of protein called myosin to enable muscle contraction. Actins can be further divided into different subtypes, including alpha-actin, beta-actin, and gamma-actin, which have distinct functions and expression patterns in the body.

Electrophoresis, polyacrylamide gel (EPG) is a laboratory technique used to separate and analyze complex mixtures of proteins or nucleic acids (DNA or RNA) based on their size and electrical charge. This technique utilizes a matrix made of cross-linked polyacrylamide, a type of gel, which provides a stable and uniform environment for the separation of molecules.

In this process:

1. The polyacrylamide gel is prepared by mixing acrylamide monomers with a cross-linking agent (bis-acrylamide) and a catalyst (ammonium persulfate) in the presence of a buffer solution.
2. The gel is then poured into a mold and allowed to polymerize, forming a solid matrix with uniform pore sizes that depend on the concentration of acrylamide used. Higher concentrations result in smaller pores, providing better resolution for separating smaller molecules.
3. Once the gel has set, it is placed in an electrophoresis apparatus containing a buffer solution. Samples containing the mixture of proteins or nucleic acids are loaded into wells on the top of the gel.
4. An electric field is applied across the gel, causing the negatively charged molecules to migrate towards the positive electrode (anode) while positively charged molecules move toward the negative electrode (cathode). The rate of migration depends on the size, charge, and shape of the molecules.
5. Smaller molecules move faster through the gel matrix and will migrate farther from the origin compared to larger molecules, resulting in separation based on size. Proteins and nucleic acids can be selectively stained after electrophoresis to visualize the separated bands.

EPG is widely used in various research fields, including molecular biology, genetics, proteomics, and forensic science, for applications such as protein characterization, DNA fragment analysis, cloning, mutation detection, and quality control of nucleic acid or protein samples.

Restrictive cardiomyopathy (RCM) is a type of heart muscle disorder characterized by impaired relaxation and filling of the lower chambers of the heart (the ventricles), leading to reduced pump function. This is caused by stiffening or rigidity of the heart muscle, often due to fibrosis or scarring. The stiffness prevents the ventricles from filling properly with blood during the diastolic phase, which can result in symptoms such as shortness of breath, fatigue, and fluid retention.

RCM is a less common form of cardiomyopathy compared to dilated or hypertrophic cardiomyopathies. It can be idiopathic (no known cause) or secondary to other conditions like amyloidosis, sarcoidosis, or storage diseases. Diagnosis typically involves a combination of medical history, physical examination, echocardiography, and sometimes cardiac MRI or biopsy. Treatment is focused on managing symptoms and addressing underlying causes when possible.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Protein isoforms are different forms or variants of a protein that are produced from a single gene through the process of alternative splicing, where different exons (or parts of exons) are included in the mature mRNA molecule. This results in the production of multiple, slightly different proteins that share a common core structure but have distinct sequences and functions. Protein isoforms can also arise from genetic variations such as single nucleotide polymorphisms or mutations that alter the protein-coding sequence of a gene. These differences in protein sequence can affect the stability, localization, activity, or interaction partners of the protein isoform, leading to functional diversity and specialization within cells and organisms.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Cardiomyopathies are a group of diseases that affect the heart muscle, leading to mechanical and/or electrical dysfunction. The American Heart Association (AHA) defines cardiomyopathies as "a heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction that usually (but not always) exhibit inappropriate ventricular hypertrophy or dilatation and frequently lead to heart failure."

There are several types of cardiomyopathies, including:

1. Dilated cardiomyopathy (DCM): This is the most common type of cardiomyopathy, characterized by an enlarged left ventricle and impaired systolic function, leading to heart failure.
2. Hypertrophic cardiomyopathy (HCM): In this type, there is abnormal thickening of the heart muscle, particularly in the septum between the two ventricles, which can obstruct blood flow and increase the risk of arrhythmias.
3. Restrictive cardiomyopathy (RCM): This is a rare form of cardiomyopathy characterized by stiffness of the heart muscle, impaired relaxation, and diastolic dysfunction, leading to reduced filling of the ventricles and heart failure.
4. Arrhythmogenic right ventricular cardiomyopathy (ARVC): In this type, there is replacement of the normal heart muscle with fatty or fibrous tissue, primarily affecting the right ventricle, which can lead to arrhythmias and sudden cardiac death.
5. Unclassified cardiomyopathies: These are conditions that do not fit into any of the above categories but still significantly affect the heart muscle and function.

Cardiomyopathies can be caused by genetic factors, acquired conditions (e.g., infections, toxins, or autoimmune disorders), or a combination of both. The diagnosis typically involves a comprehensive evaluation, including medical history, physical examination, electrocardiogram (ECG), echocardiography, cardiac magnetic resonance imaging (MRI), and sometimes genetic testing. Treatment depends on the type and severity of the condition but may include medications, lifestyle modifications, implantable devices, or even heart transplantation in severe cases.

Isoenzymes, also known as isoforms, are multiple forms of an enzyme that catalyze the same chemical reaction but differ in their amino acid sequence, structure, and/or kinetic properties. They are encoded by different genes or alternative splicing of the same gene. Isoenzymes can be found in various tissues and organs, and they play a crucial role in biological processes such as metabolism, detoxification, and cell signaling. Measurement of isoenzyme levels in body fluids (such as blood) can provide valuable diagnostic information for certain medical conditions, including tissue damage, inflammation, and various diseases.

Thiadiazines are a class of heterocyclic compounds containing a five-membered ring with two nitrogen atoms and two sulfur atoms. In the context of pharmaceuticals, thiadiazine derivatives are commonly used as therapeutic agents, particularly in the treatment of various cardiovascular diseases.

The most well-known thiadiazine derivative is hydrochlorothiazide, which is a diuretic drug used to treat hypertension and edema associated with heart failure, liver cirrhosis, and kidney disease. Hydrochlorothiazide works by inhibiting the reabsorption of sodium and chloride ions in the distal convoluted tubule of the nephron, thereby increasing water excretion and reducing blood volume and pressure.

Other thiadiazine derivatives have been investigated for their potential therapeutic benefits, including anti-inflammatory, anticonvulsant, and antimicrobial activities. However, many of these compounds have not yet been approved for clinical use due to safety concerns or lack of efficacy.

Acute Coronary Syndrome (ACS) is a term used to describe a range of conditions associated with sudden, reduced blood flow to the heart muscle. This reduction in blood flow, commonly caused by blood clots forming in coronary arteries, can lead to damage or death of the heart muscle and is often characterized by symptoms such as chest pain, shortness of breath, and fatigue.

There are three main types of ACS:

1. Unstable Angina: This occurs when there is reduced blood flow to the heart muscle, causing chest pain or discomfort, but the heart muscle is not damaged. It can be a warning sign for a possible future heart attack.
2. Non-ST Segment Elevation Myocardial Infarction (NSTEMI): This type of heart attack occurs when there is reduced blood flow to the heart muscle, causing damage or death of some of the muscle cells. However, the electrical activity of the heart remains relatively normal.
3. ST Segment Elevation Myocardial Infarction (STEMI): This is a serious and life-threatening type of heart attack that occurs when there is a complete blockage in one or more of the coronary arteries, causing extensive damage to the heart muscle. The electrical activity of the heart is significantly altered, which can lead to dangerous heart rhythms and even cardiac arrest.

Immediate medical attention is required for anyone experiencing symptoms of ACS, as prompt treatment can help prevent further damage to the heart muscle and reduce the risk of complications or death. Treatment options may include medications, lifestyle changes, and procedures such as angioplasty or bypass surgery.

Naphthalenesulfonates are a group of chemical compounds that consist of a naphthalene ring, which is a bicyclic aromatic hydrocarbon, substituted with one or more sulfonate groups. Sulfonates are salts or esters of sulfuric acid. Naphthalenesulfonates are commonly used as detergents, dyes, and research chemicals.

In the medical field, naphthalenesulfonates may be used in diagnostic tests to detect certain enzyme activities or metabolic disorders. For example, 1-naphthyl sulfate is a substrate for the enzyme arylsulfatase A, which is deficient in individuals with the genetic disorder metachromatic leukodystrophy. By measuring the activity of this enzyme using 1-naphthyl sulfate as a substrate, doctors can diagnose or monitor the progression of this disease.

It's worth noting that some naphthalenesulfonates have been found to have potential health hazards and environmental concerns. For instance, sodium naphthalenesulfonate has been classified as a possible human carcinogen by the International Agency for Research on Cancer (IARC). Therefore, their use should be handled with caution and in accordance with established safety protocols.

Muscle contraction is the physiological process in which muscle fibers shorten and generate force, leading to movement or stability of a body part. This process involves the sliding filament theory where thick and thin filaments within the sarcomeres (the functional units of muscles) slide past each other, facilitated by the interaction between myosin heads and actin filaments. The energy required for this action is provided by the hydrolysis of adenosine triphosphate (ATP). Muscle contractions can be voluntary or involuntary, and they play a crucial role in various bodily functions such as locomotion, circulation, respiration, and posture maintenance.

An acute disease is a medical condition that has a rapid onset, develops quickly, and tends to be short in duration. Acute diseases can range from minor illnesses such as a common cold or flu, to more severe conditions such as pneumonia, meningitis, or a heart attack. These types of diseases often have clear symptoms that are easy to identify, and they may require immediate medical attention or treatment.

Acute diseases are typically caused by an external agent or factor, such as a bacterial or viral infection, a toxin, or an injury. They can also be the result of a sudden worsening of an existing chronic condition. In general, acute diseases are distinct from chronic diseases, which are long-term medical conditions that develop slowly over time and may require ongoing management and treatment.

Examples of acute diseases include:

* Acute bronchitis: a sudden inflammation of the airways in the lungs, often caused by a viral infection.
* Appendicitis: an inflammation of the appendix that can cause severe pain and requires surgical removal.
* Gastroenteritis: an inflammation of the stomach and intestines, often caused by a viral or bacterial infection.
* Migraine headaches: intense headaches that can last for hours or days, and are often accompanied by nausea, vomiting, and sensitivity to light and sound.
* Myocardial infarction (heart attack): a sudden blockage of blood flow to the heart muscle, often caused by a buildup of plaque in the coronary arteries.
* Pneumonia: an infection of the lungs that can cause coughing, chest pain, and difficulty breathing.
* Sinusitis: an inflammation of the sinuses, often caused by a viral or bacterial infection.

It's important to note that while some acute diseases may resolve on their own with rest and supportive care, others may require medical intervention or treatment to prevent complications and promote recovery. If you are experiencing symptoms of an acute disease, it is always best to seek medical attention to ensure proper diagnosis and treatment.

Dilated cardiomyopathy (DCM) is a type of cardiomyopathy characterized by the enlargement and weakened contraction of the heart's main pumping chamber (the left ventricle). This enlargement and weakness can lead to symptoms such as shortness of breath, fatigue, and fluid retention. DCM can be caused by various factors including genetics, viral infections, alcohol and drug abuse, and other medical conditions like high blood pressure and diabetes. It is important to note that this condition can lead to heart failure if left untreated.

An immunoassay is a biochemical test that measures the presence or concentration of a specific protein, antibody, or antigen in a sample using the principles of antibody-antigen reactions. It is commonly used in clinical laboratories to diagnose and monitor various medical conditions such as infections, hormonal disorders, allergies, and cancer.

Immunoassays typically involve the use of labeled reagents, such as enzymes, radioisotopes, or fluorescent dyes, that bind specifically to the target molecule. The amount of label detected is proportional to the concentration of the target molecule in the sample, allowing for quantitative analysis.

There are several types of immunoassays, including enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA), fluorescence immunoassay (FIA), and chemiluminescent immunoassay (CLIA). Each type has its own advantages and limitations, depending on the sensitivity, specificity, and throughput required for a particular application.

Cardiac myosins are a type of myosin protein that are specifically expressed in the cardiac muscle cells (or cardiomyocytes) of the heart. These proteins play a crucial role in the contraction and relaxation of heart muscles, which is essential for proper heart function and blood circulation.

Myosins are molecular motors that use chemical energy from ATP to generate force and movement. In the context of cardiac muscle cells, cardiac myosins interact with another protein called actin to form sarcomeres, which are the basic contractile units of muscle fibers. During contraction, the heads of cardiac myosin molecules bind to actin filaments and pull them together, causing the muscle fiber to shorten and generate force.

There are different isoforms of cardiac myosins that can vary in their structure and function. Mutations in the genes encoding these proteins have been linked to various forms of cardiomyopathy, which are diseases of the heart muscle that can lead to heart failure and other complications. Therefore, understanding the structure and function of cardiac myosins is an important area of research for developing therapies and treatments for heart disease.

"Pectinidae" is not a medical term. It is a taxonomic category in the field of biology, specifically a family of marine bivalve mollusks commonly known as scallops. The members of this family are characterized by their fan-shaped shells and their ability to swim by clapping their valves together. If you have any questions about a medical term, I would be happy to help with that instead.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Heart disease is a broad term for a class of diseases that involve the heart or blood vessels. It's often used to refer to conditions that include:

1. Coronary artery disease (CAD): This is the most common type of heart disease. It occurs when the arteries that supply blood to the heart become hardened and narrowed due to the buildup of cholesterol and other substances, which can lead to chest pain (angina), shortness of breath, or a heart attack.

2. Heart failure: This condition occurs when the heart is unable to pump blood efficiently to meet the body's needs. It can be caused by various conditions, including coronary artery disease, high blood pressure, and cardiomyopathy.

3. Arrhythmias: These are abnormal heart rhythms, which can be too fast, too slow, or irregular. They can lead to symptoms such as palpitations, dizziness, and fainting.

4. Valvular heart disease: This involves damage to one or more of the heart's four valves, which control blood flow through the heart. Damage can be caused by various conditions, including infection, rheumatic fever, and aging.

5. Cardiomyopathy: This is a disease of the heart muscle that makes it harder for the heart to pump blood efficiently. It can be caused by various factors, including genetics, viral infections, and drug abuse.

6. Pericardial disease: This involves inflammation or other problems with the sac surrounding the heart (pericardium). It can cause chest pain and other symptoms.

7. Congenital heart defects: These are heart conditions that are present at birth, such as a hole in the heart or abnormal blood vessels. They can range from mild to severe and may require medical intervention.

8. Heart infections: The heart can become infected by bacteria, viruses, or parasites, leading to various symptoms and complications.

It's important to note that many factors can contribute to the development of heart disease, including genetics, lifestyle choices, and certain medical conditions. Regular check-ups and a healthy lifestyle can help reduce the risk of developing heart disease.

Chymotrypsin is a proteolytic enzyme, specifically a serine protease, that is produced in the pancreas and secreted into the small intestine as an inactive precursor called chymotrypsinogen. Once activated, chymotrypsin helps to digest proteins in food by breaking down specific peptide bonds in protein molecules. Its activity is based on the recognition of large hydrophobic side chains in amino acids like phenylalanine, tryptophan, and tyrosine. Chymotrypsin plays a crucial role in maintaining normal digestion and absorption processes in the human body.

Myosin Heavy Chains are the large, essential components of myosin molecules, which are responsible for the molecular motility in muscle cells. These heavy chains have a molecular weight of approximately 200 kDa and form the motor domain of myosin, which binds to actin filaments and hydrolyzes ATP to generate force and movement during muscle contraction. There are several different types of myosin heavy chains, each with specific roles in various tissues and cellular functions. In skeletal and cardiac muscles, for example, myosin heavy chains have distinct isoforms that contribute to the contractile properties of these tissues.

A Receiver Operating Characteristic (ROC) curve is a graphical representation used in medical decision-making and statistical analysis to illustrate the performance of a binary classifier system, such as a diagnostic test or a machine learning algorithm. It's a plot that shows the tradeoff between the true positive rate (sensitivity) and the false positive rate (1 - specificity) for different threshold settings.

The x-axis of an ROC curve represents the false positive rate (the proportion of negative cases incorrectly classified as positive), while the y-axis represents the true positive rate (the proportion of positive cases correctly classified as positive). Each point on the curve corresponds to a specific decision threshold, with higher points indicating better performance.

The area under the ROC curve (AUC) is a commonly used summary measure that reflects the overall performance of the classifier. An AUC value of 1 indicates perfect discrimination between positive and negative cases, while an AUC value of 0.5 suggests that the classifier performs no better than chance.

ROC curves are widely used in healthcare to evaluate diagnostic tests, predictive models, and screening tools for various medical conditions, helping clinicians make informed decisions about patient care based on the balance between sensitivity and specificity.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Myosin subfragments refer to the smaller components that result from the dissociation or proteolytic digestion of myosin, a motor protein involved in muscle contraction. The two main subfragments are called S1 and S2.

S1 is the "head" of the myosin molecule, which contains the actin-binding site, ATPase activity, and the ability to generate force and motion during muscle contraction. It has a molecular weight of approximately 120 kDa.

S2 is the "tail" of the myosin molecule, which has a molecular weight of about 350 kDa and is responsible for forming the backbone of the thick filament in muscle sarcomeres. S2 can be further divided into light meromyosin (LMM) and heavy meromyosin (HMM). HMM consists of S1 and part of S2, while LMM comprises the remaining portion of S2.

These subfragments are essential for understanding myosin's structure, function, and interactions with other muscle components at a molecular level.

Cardiac myocytes are the muscle cells that make up the heart muscle, also known as the myocardium. These specialized cells are responsible for contracting and relaxing in a coordinated manner to pump blood throughout the body. They differ from skeletal muscle cells in several ways, including their ability to generate their own electrical impulses, which allows the heart to function as an independent rhythmical pump. Cardiac myocytes contain sarcomeres, the contractile units of the muscle, and are connected to each other by intercalated discs that help coordinate contraction and ensure the synchronous beating of the heart.

Adenosine triphosphatases (ATPases) are a group of enzymes that catalyze the conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy, which is used to drive various cellular processes such as muscle contraction, transport of ions across membranes, and synthesis of proteins and nucleic acids.

ATPases are classified into several types based on their structure, function, and mechanism of action. Some examples include:

1. P-type ATPases: These ATPases form a phosphorylated intermediate during the reaction cycle and are involved in the transport of ions across membranes, such as the sodium-potassium pump and calcium pumps.
2. F-type ATPases: These ATPases are found in mitochondria, chloroplasts, and bacteria, and are responsible for generating a proton gradient across the membrane, which is used to synthesize ATP.
3. V-type ATPases: These ATPases are found in vacuolar membranes and endomembranes, and are involved in acidification of intracellular compartments.
4. A-type ATPases: These ATPases are found in the plasma membrane and are involved in various functions such as cell signaling and ion transport.

Overall, ATPases play a crucial role in maintaining the energy balance of cells and regulating various physiological processes.

... , or the troponin complex, is a complex of three regulatory proteins (troponin C, troponin I, and troponin T) that are ... Calcium-binding protein Troponin C Troponin I Troponin T PDB: 1J1E​; Takeda S, Yamashita A, Maeda K, Maeda Y (2003). "Structure ... Troponin is found in both skeletal muscle and cardiac muscle, but the specific versions of troponin differ between types of ... Troponin at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Troponins at Lab Tests Online (CS1 maint: ...
Slow skeletal troponin T1, TNNT1 (19q13.4, 191041) Cardiac troponin T2, TNNT2 (1q32, 191045) Fast skeletal troponin T3, TNNT3 ( ... Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of ... Troponin T binds to tropomyosin and helps position it on actin, and together with the rest of the troponin complex, modulates ... He also developed the troponin T assay. In patients with stable coronary artery disease, the troponin T concentration has long ...
Troponin Troponin T Troponin C Sliding filament model Takeda, Soichi; Yamashita, Atsuko; Maeda, Kayo; Maéda, Yuichiro (July ... Troponin I is a cardiac and skeletal muscle protein family. It is a part of the troponin protein complex, where it binds to ... Reductions in troponin I levels proved to reduce the risk of future CVD. - High sensitive troponin I used as a screening tool ... Troponin I prevents myosin from binding to actin in relaxed muscle. When calcium binds to the troponin C, it causes ...
A8V D145E A31S C84Y E134D Y5H I148V Troponin Troponin T Troponin I Calcium-binding protein Sliding filament model Kalyva A, ... Troponin C is a protein which is part of the troponin complex. It contains four calcium-binding EF hands, although different ... Fast troponin C, TNNC2 (20q12-q13.11, Online Mendelian Inheritance in Man (OMIM): 191039) Point mutations can occur in troponin ... The C lobe serves a structural purpose and binds to the N domain of troponin I (TnI). The C lobe can bind either Ca2+ or Mg2+. ...
Chemical compounds can bind to troponin C to act as troponin activators (calcium sensitizers) or troponin inhibitors (calcium ... and cardiac troponin T (cTnT), whereas cTnC binds to slow skeletal troponin I (ssTnI) and troponin T (ssTnT) in slow-twitch ... Troponin C, also known as TN-C or TnC, is a protein that resides in the troponin complex on actin thin filaments of striated ... Troponin C is encoded by the TNNC1 gene in humans for both cardiac and slow skeletal muscle. Cardiac troponin C (cTnC) is a 161 ...
... is a protein that in humans is encoded by the TNNC2 gene. Troponin (Tn), is a key protein complex ... 1998). "Crystal structure of troponin C in complex with troponin I fragment at 2.3-A resolution". Proc. Natl. Acad. Sci. U.S.A ... 1997). "Fine mapping of five human skeletal muscle genes: alpha-tropomyosin, beta-tropomyosin, troponin-I slow-twitch, troponin ... "Entrez Gene: TNNC2 troponin C type 2 (fast)". Romero-Herrera AE, Castillo O, Lehmann H (1977). "Human skeletal muscle proteins ...
... troponin C which is calcium binding, troponin T that plays the role with tropomyosin, and troponin I which has an inhibitory ... Solaro, R. John; Rosevear, Paul; Kobayashi, Tomoyoshi (April 2008). "The unique functions of cardiac troponin I in the control ... A8V is point mutation on Troponin C (cTNC) that leads to a hypertrophic cardiomyopathy. The coordinated cardiac muscle ... Ohtsuki, Iwao; Morimoto, Sachio (April 2008). "Troponin: Regulatory function and disorders". Biochemical and Biophysical ...
Cardiac TnT is the largest of the three troponin subunits (cTnT, troponin I (TnI), troponin C (TnC)) on the actin thin filament ... "Dephosphorylation specificities of protein phosphatase for cardiac troponin I, troponin T, and sites within troponin T". ... He X, Liu Y, Sharma V, Dirksen RT, Waugh R, Sheu SS, Min W (Jul 2003). "ASK1 associates with troponin T and induces troponin T ... Noland TA, Raynor RL, Kuo JF (Dec 1989). "Identification of sites phosphorylated in bovine cardiac troponin I and troponin T by ...
In 2006, his essay "Troponin trumps common sense", which discussed the appropriate use of the troponin test, drew the attention ... In a reply, he stated "rather than allowing troponin to trump common sense, we should inject more common sense into the process ... "Reply: Troponin Trumps Common Sense" (PDF). Journal of the American College of Cardiology. 48: 2357-2358. 5 December 2006. ... Other noted publications have included his 2006 article titled "Troponin trumps common sense" and "Women Cardiologists: Why so ...
"Troponins". medscape. Retrieved 2017-07-24. Updated: Jan 14, 2015 Brenden CK, Hollander JE, Guss D, et al. (May 2006). "Gray ... In addition, some values, including troponin I and brain natriuretic peptide, are given as the estimated appropriate cutoffs to ... Baum, Hannsjörg; Hinze, Anika; Bartels, Peter; Neumeier, Dieter (2004-12-01). "Reference values for cardiac troponins T and I ... High sensitive troponin I in pediatric age". Clinica Chimica Acta. 458: 68-71. doi:10.1016/j.cca.2016.04.029. ISSN 0009-8981. ...
Troponin...etc.). A small portion of carryover could lead to erroneous results. IUPAC made a recommendation in 1991 for the ... carryover of cardiac High sensitivity Troponin assay would be catastrophic. Haeckel, R. (1991-01-01). "Proposals for the ...
Fetal Troponin T is a cardiac protein found in adults and infants. There are 4 Troponin T (TnT) isoforms found in fetal cardiac ... Fetal Troponin T and Troponin I isoforms. Fetal Hemoglobin is a member of erythrocytes called F-cells. It is a tetramer protein ... Fetal Troponin I (TnI) is a cardiac and skeletal protein found in adults and infants, with isomers specific to each. Two ... Anderson, P A; Malouf, N N; Oakeley, A E; Pagani, E D; Allen, P D (November 1991). "Troponin T isoform expression in humans. A ...
A novel troponin T-like protein". Hypertension. 11 (6 Pt 2): 620-6. doi:10.1161/01.hyp.11.6.620. PMID 2455687. Coulier F, ...
Troponin levels should also be ordered. Important to note, negative findings on both ECG and troponin levels do not exclude BCI ... If both ECG and troponin levels are abnormal, an appropriate next step in evaluation would involve ordering an echocardiography ... As mentioned under Evaluation, an abnormal ECG and elevated troponin levels should elicit continued cardiac monitoring to look ...
A novel troponin T-like protein". Hypertension. 11 (6 Pt 2): 620-6. doi:10.1161/01.hyp.11.6.620. PMID 2455687. Taylor A, Erba ... troponin C, Alzheimer amyloid precursor protein and pro-interleukin 1 beta as substrates of the protease from human ...
Calbindin Calmodulin Calsequestrin Troponin Kinjo, Tashi G; Schnetkamp, Paul PM. Ca2+ Chemistry, Storage and Transport in ...
Pfleiderer P, Sumandea MP, Rybin VO, Wang C, Steinberg SF (2009). "Raf-1: a novel cardiac troponin T kinase". J. Muscle Res. ... cardiac muscle troponin T (TnTc), etc. The retinoblastoma protein (pRb) and Cdc25 phosphatase were also suggested as possible ...
... does not contain the protein troponin; instead calmodulin (which takes on the regulatory role in smooth muscle), ... Contraction is initiated by a calcium-regulated phosphorylation of myosin, rather than a calcium-activated troponin system. ... smooth muscle does not contain the calcium-binding protein troponin. ...
Troponin "CREATINE KINASE - MB CK-MB LQ" (PDF). Cabaniss, C. Daniel (1990), Walker, H. Kenneth; Hall, W. Dallas; Hurst, J. ... the test has been superseded by the troponin test. However, recently, there have been improvements to the test that involve ...
Sensitizing troponin-C to the effects of calcium. Phosphorylating L-type calcium channels. This will increase their ... More calcium available for Troponin to use will increase the force developed. Decreasing contractility is done primarily by ...
Li Q, Shen PY, Wu G, Chen XZ (January 2003). "Polycystin-2 interacts with troponin I, an angiogenesis inhibitor". Biochemistry ...
It is a tissue-specific subtype of troponin I, which in turn is a part of the troponin complex. The TNNI3 gene encoding cardiac ... Vassylyev DG, Takeda S, Wakatsuki S, Maeda K, Maéda Y (Apr 1998). "Crystal structure of troponin C in complex with troponin I ... Noland TA, Raynor RL, Kuo JF (Dec 1989). "Identification of sites phosphorylated in bovine cardiac troponin I and troponin T by ... Martin AF (Jan 1981). "Turnover of cardiac troponin subunits. Kinetic evidence for a precursor pool of troponin-I". The Journal ...
Shah, Ajay M.; Solaro, R. John; Layland, Joanne (2005-04-01). "Regulation of cardiac contractile function by troponin I ... troponin I, myosin binding protein C, and potassium channels. This increases inotropy as well as lusitropy, increasing ...
Serum troponin elevation is a characteristic biomarker of MI. Depending on the severity of ischemia, MIs are categorized as ... Wu AH (2017-09-01). "Release of cardiac troponin from healthy and damaged myocardium". Frontiers in Laboratory Medicine. 1 (3 ... Lactate accumulation reduces contractility and eventually necroses cardiomyocytes, releasing their troponin storage into the ...
Calcium ions also combine with the regulatory protein troponin C in the troponin complex to enable contraction of the cardiac ... Two tests of troponin are often taken-one at the time of initial presentation, and another within 3-6 hours, with either a high ... Troponin is a sensitive biomarker for a heart with insufficient blood supply. It is released 4-6 hours after injury, and ... These are mostly associated with muscle contraction, and bind with actin, myosin, tropomyosin, and troponin. They include MYH6 ...
Tanokura M, Ohtsuki I (1984). "Interactions among chymotryptic troponin T subfragments, tropomyosin, troponin I and troponin C ... Pearlstone JR, Smillie LB (1983). "Effects of troponin-I plus-C on the binding of troponin-T and its fragments to alpha- ... In human cardiac muscle the ratio of α-Tm to β-Tm is roughly 5:1. Tm functions in association with the troponin complex to ... In addition to actin, Tm binds troponin T (TnT). TnT tethers the region of head-to-tail overlap of subsequent Tm molecules to ...
H-FABP measured with troponin shows increased sensitivity of 20.6% over troponin at 3-6 hours following chest pain onset. This ... The effectiveness of using the combination of H-FABP with troponin to diagnose MI within 6 hours is well reported. In addition ... FABP3 is known to interact with TNNI3K in the context of interacting with cardiac troponin I. The protein also interacts with, ... Alongside D-dimer, NT-proBNP and peak troponin T, it was the only cardiac biomarker that proved to be a statistically ...
Troponin levels increase in 35-50% of people with pericarditis. Electrocardiogram (ECG) changes in acute pericarditis mainly ... Acute pericarditis is associated with a modest increase in serum creatine kinase MB (CK-MB). and cardiac troponin I (cTnI), ...
Tsalkova TN, Privalov PL (1985). "Thermodynamic study of domain organization in troponin C and calmodulin". Journal of ...
Calcium ions then bind to troponin, which is associated with tropomyosin. Binding causes changes in the shape of troponin and ... In animals, it is an important component of the muscular system which works in conjunction with troponin to regulate muscle ... The thin filament is made of actin, tropomyosin, and troponin. The contraction of skeletal muscle is triggered by nerve ... Structural and biochemical studies suggest that the position of tropomyosin and troponin on the thin filament regulates the ...
Troponin, or the troponin complex, is a complex of three regulatory proteins (troponin C, troponin I, and troponin T) that are ... Calcium-binding protein Troponin C Troponin I Troponin T PDB: 1J1E​; Takeda S, Yamashita A, Maeda K, Maeda Y (2003). "Structure ... Troponin is found in both skeletal muscle and cardiac muscle, but the specific versions of troponin differ between types of ... Troponin at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Troponins at Lab Tests Online (CS1 maint: ...
There are two troponin C subtypes: troponin C1 and C2. Troponin C1 is skeletal and cardiac type whereas troponin C2 is skeletal ... Troponin (1980-1996). All MeSH CategoriesChemicals and Drugs CategoryMacromolecular SubstancesMultiprotein ComplexesTroponin ... Troponin C1 is a BIOMARKER for damaged or injured CARDIAC MYOCYTES and mutations in troponin C1 gene are associated with ... Troponin C. A TROPONIN complex subunit that binds calcium and help regulate calcium-dependent muscle contraction. ...
A troponin test measures the levels of troponin T or troponin I proteins in the blood. These proteins are released when the ... A troponin test measures the levels of troponin T or troponin I proteins in the blood. These proteins are released when the ... A troponin test measures the levels of troponin T or troponin I proteins in the blood. These proteins are released when the ... TroponinI; TnI; TroponinT; TnT; Cardiac-specific troponin I; Cardiac-specific troponin T; cTnl; cTnT ...
New evidence points to the prognostic value of cardiac troponin T in identifying myocardial injury and subsequent mortality ... Researchers used postoperative troponin release levels to assess the association of perioperative myocardial injury with 30-day ... The statistical method used to determine cardiac troponin values may have resulted in thresholds with a lower sensitivity. The ... Cite this: Cardiac Troponin Predicts Mortality Post Surgery - Medscape - Sep 27, 2023. ...
Abbotts Architect Stat troponin-I assay can identify myocardial infarction several hours sooner than standard troponin tests ... They cite a study in The BMJ in 2015, which found that the test uncovered twice as many MIs in women than standard troponin ... "Women may particularly benefit from this technology as they often have lower levels of troponin than men, which could lead to ... "The addition of Abbotts high sensitivity troponin-I assay to the laboratorys diagnostic testing menu is a great step forward ...
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Centers RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.. ...
Doukky et als retrospective study showing that highly sensitive cardiac troponin I assay provides a good prognostic negative ...
Since the initial 1st-generation assays, 5th-generation high-sensitivity cardiac troponin (hs-cTn) assays have been developed, ... The role of cardiac troponins as diagnostic biomarkers of myocardial injury in the context of acute coronary syndrome (ACS) is ... Cardiac biomarkers of acute coronary syndrome: from history to high-sensitivity cardiac troponin Intern Emerg Med. 2017 Mar;12( ... The role of cardiac troponins as diagnostic biomarkers of myocardial injury in the context of acute coronary syndrome (ACS) is ...
O Quidel Triage Teste de Troponina I é um imunoensaio de fluorescência da próxima geração que deve ser usado com o QuidelTriage MeterPro no local do tratamento para fazer medições quantitativas de troponina I da próxima geração. (Não disponível nos EUA)
... an ultra-sensitive test that measures cardiac troponin at lower levels than most existing assays. ... myADLM.org // Clinical Laboratory News // All Articles // Ultra-Sensitive Cardiac Troponin Assay Receives CE Mark ... Singulex has received the CE mark for its Sgx Clarity cTnI assay, an ultra-sensitive test that measures cardiac troponin at ...
High-sensitivity cardiac troponin T levels are increased in stable COPD Message subject: (Your Name) has forwarded a page to ...
Cardiac troponin T isoforms affect the Ca(2+) sensitivity of force development in the presence of slow skeletal troponin I: ... Cardiac troponin T mutation R141W found in dilated cardiomyopathy stabilizes the troponin T-tropomyosin interaction and causes ... Troponin T or troponin I or CK-MB (or none?). Collinson, P.O. Eur. Heart J. (1998) [Pubmed] ... as well as the troponins--cardiac troponin T (cTnT) and cardiac troponin I (cTnI)--are all used for assessment of the suspected ...
Methods: Cardiac troponin I was investigated by direct sequencing and fluorescent (F)-SSCP analysis in 748 consecutive HCM ... Frequency and clinical expression of cardiac troponin I mutations in 748 consecutive families with hypertrophic cardiomyopathy ... caused by mutations in the gene for cardiac troponin I (TNNI3). ...
... either cardiac troponin I or T, has become the culprit of clinical decision making in patients with suspected acute coronary ... The measurement of cardiac troponins, either cardiac troponin I or T, has become the culprit of clinical decision making in ... "Ultra-sensitive" cardiac troponins: Requirements for effective implementation in clinical practice. Giuseppe Lippi orcid.org/ ... "Ultra-sensitive" cardiac troponins: Requirements for effective implementation in clinical practice." Biochemia Medica 28, br. 3 ...
High-Sensitivity Troponin T and Copeptin in Non-ST Acute Coronary Syndromes: Implications for Prognosis and Role of hsTnT and ... S. Gupta and J. A. de Lemos, "Use and misuse of cardiac troponins in clinical practice," Progress in Cardiovascular Diseases, ... T. Omland, J. A. De Lemos, M. S. Sabatine et al., "A sensitive cardiac troponin T assay in stable coronary artery disease," New ... S. James, P. Armstrong, R. Califf et al., "Troponin T levels and risk of 30-day outcomes in patients with the acute coronary ...
Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury. ... The usefulness of serum troponin levels in evaluating cardiac injury.. *An evaluation of serum troponin T and signal-averaged ... Serum troponin-I as an indicator of clinically significant myocardial injury in paediatric trauma patients. ... Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury.. J ...
Proteintech Anti-Cardiac Troponin I Monoclonal (1D5D6), Catalog # CL488-66376. Tested in Immunocytochemistry (ICC/IF) and ... Cardiac Troponin I (Cardiac-specific troponin I, TnI, Troponin I) is an integral inhibitory protein in cardiac muscle that ... and troponin T (TnT). The TnT subunit of troponin binds to tropomyosin-t form, a troponin-tropomyosin complex, anchored in ... troponin 1, type 3; troponin I type 3 (cardiac); Troponin I, cardiac muscle ...
High-Sensitivity Cardiac Troponin for Risk Assessment in Chronic CAD. Aug 02, 2023 ... High-Sensitivity Cardiac Troponin for Risk Assessment in Patients With Chronic Coronary Artery Disease. J Am Coll Cardiol 2023; ... YOU ARE HERE: Home , Latest in Cardiology , High-Sensitivity Cardiac Troponin for Risk Assessment in Chronic CAD ... The purpose of this study was to evaluate whether high-sensitivity cardiac troponin I (hs-cTnI) in patients with undergoing ...
A high-sensitivity troponin* assay available in the United States for the near-patient setting, Troponin I on the Stratus® CS ... Cardiac troponins have high myocardial tissue specificity as well as high clinical sensitivity. Serum troponin is a very ... Our protocol specific to troponin is initial high-sensitivity troponin*, and repeat at 90 minutes. If both are negative, the ... Why High-Sensitivity Troponin*? According to National Academy of Clinical Biochemistry (NACB) Guidelines, assays for cardiac ...
Is troponin suitable to predict ACS in stroke patients?. This question was addressed by the Troponin Elevation in Acute ... Coronary Angiographic Findings in Acute Ischemic Stroke Patients With Elevated Cardiac Troponin: The Troponin Elevation in ... of stroke patients with elevated troponin, thus demonstrating that elevated troponin should not be ignored in acute stroke ... Elevated troponin in acute ischemic stroke - a matter of debate?. 23/11/2018. /in Stroke Research. ...
Troponin assays have developed with successive generations such that they can detect increasingly low levels of troponin.4 This ... Many clinicians will agree that there is a problem in daily practice with troponin-itis when any abnormal troponin result is ... It also means that the concept of a negative troponin becomes relatively meaningless as troponin at some level can almost ... the troponin assay is unable to exclude unstable angina, a high-risk clinical syndrome without MI (and with no troponin release ...
Comprehensive supplier list for Anti-Bovine Cardiac Troponin T,Anti-Bovine Factor V Monoclonal Antibody ... Anti-Bovine Cardiac Troponin T (2 suppliers). Anti-Bovine Factor V Monoclonal Antibody (2 suppliers). Anti-Bovine Gamma-1 ...
Quality controls with lower cardiac troponin concentrations are needed to monitor and validate hs-cTn assay performance. ... Cardiac troponins (cTn), cardiac troponin I (cTnI) and cardiac troponin T (cTnT), are important analytes for acute myocardial ... Best Practices for Monitoring the Precision of Cardiac Troponin Testing. Jun 2, 2023 , Controls , ... 99thpercentiles for cardiac troponin assay methods addressed in this article are greater than their respective assay methods ...
Discover how a study in Italy has validated the high-sensitivity troponin I assay as an essential tool for one diagnostic ... These videos are part of a series of educational videos focusing on the clinical utility of high-sensitivity troponin I. Hear ... Evaluating the Performance of a High-Sensitivity Troponin I Assay in a Clinical Chemistry Laboratory. Dr. Tommaso Fasano. Santa ... Biochemists in Paris Evaluate the High-Sensitivity Troponin I Assay (French with English subtitles). Dr. Katell Peoch. MCUPH. ...
Elevated high-sensitivity troponin is associated with subclinical cardiac dysfunction in patients recovered from coronavirus ... Keywords: COVID-19, myocardial injury, high-sensitivity troponin levels, left ventricular global longitudinal strain, COVID-19 ... patients with high-sensitivity troponin levels (hsTnT) and echocardiography. In this single-center cohort study, 215 COVID-19 ...
This study has not yet been registered on ClinicalTrials.gov, which is currently a pre-requisite for display of detailed eligibility criteria.. ...
Most of the studies (17) involved measurement of troponin I, with the rest looking at troponin T. Troponin was detectable in a ... No History of CVD, Yet Detectable Troponin Levels. Although cardiac troponins have been measured for years for diagnosing acute ... High-Sensitivity Troponin Assays May Help With Response to Statins and Other Meds By Todd Neale ... First High-Sensitivity Troponin Assay Finally Comes to the United States By Todd Neale ...
We aimed to assess the relationship between LAP burden and circulating levels of high-sensitivity cardiac troponin T (hs-cTnT ... We aimed to assess the relationship between LAP burden and circulating levels of high-sensitivity cardiac troponin T (hs-cTnT ... Low-attenuation coronary plaque burden and troponin release in chronic coronary syndrome: A mediation analysis.. Oct 23, 2023 ...
Troponin I Type 3, Cardiac) ELISA Kit from Gentaur Elisa Kits. Cat Number: G-EC-05824. USA, UK & Europe Distribution. ... Rat TNNI3/cTn-I (Troponin I Type 3, Cardiac) ELISA Kit DataSheet. Citation #1. Citation #2. Citation #3. Citation #4. Citation ... Rat TNNI3/cTn-I (Troponin I Type 3, Cardiac) ELISA Kit , G-EC-05824. Gentaur Elisa ... Rat TNNI3/cTn-I (Troponin I Type 3, Cardiac) ELISA Kit , G-EC-05824 ...
  • Since the initial 1st-generation assays, 5th-generation high-sensitivity cardiac troponin (hs-cTn) assays have been developed, and are now widely used. (nih.gov)
  • Singulex has received the CE mark for its Sgx Clarity cTnI assay, an ultra-sensitive test that measures cardiac troponin at lower levels than most existing assays. (aacc.org)
  • The very recent commercialization of methods with further improved analytical sensitivity (i.e., "ultra-sensitive" assays), which allow to measure cardiac troponin values in the vast majority of healthy subjects, is now challenging the diagnostic paradigm based on early rule-out of subjects with cardiac troponin values comprised between the 99th percentile and LoD. (srce.hr)
  • Scheitz JF, Nolte CH, Laufs U, Endres M. Application and interpretation of high-sensitivity cardiac troponin assays in patients with acute ischemic stroke. (eso-stroke.org)
  • New high-sensitivity troponin assays will reduce the threshold for the diagnosis of myocardial infarction (MI), as specified in the 2012 third Universal Definition of MI. (bjcardio.co.uk)
  • At the 2012 European Society of Cardiology (ESC) meeting the Universal Definition of MI was updated for the third time in a decade, 3 and a major inclusion was the introduction of high-sensitivity cardiac troponin assays, which are again likely to change the rate of MI diagnosis. (bjcardio.co.uk)
  • Troponin assays have developed with successive generations such that they can detect increasingly low levels of troponin. (bjcardio.co.uk)
  • 6 This is as expected for a more sensitive assay, as it is simply detecting the same troponin release at an earlier time than conventional assays. (bjcardio.co.uk)
  • Recent approvals of high sensitivity cardiac troponin (hs-cTn) assays by the U.S. Food and Drug Administration (FDA) and international regulatory bodies have enabled clinical labs to develop more sophisticated diagnostic protocols based on utilization of low cTn measurements at or near the assays' limit of detection (LoD) to expediate and improve the accuracy of acute myocardial infarction diagnosis. (clpmag.com)
  • Non-high sensitivity cardiac troponin assays lack the analytical sensitivity to reliably measure small cTn concentrations and their subsequent changes below the 99th percentile upper reference limit (URL). (clpmag.com)
  • Assays for hs-cTnI and hs-cTnT have allowed clinical labs to shift emphasis from using cardiac troponin as binary tests (in which the 99th percentile URL of a healthy reference population was used as a cut-off for defining normal vs increased cTn values) to more complex diagnostic protocols utilizing cTn values below the 99th percentiles' URLs. (clpmag.com)
  • Siemens Healthineers offers proven, true high-sensitivity troponin I assays that provide fast, actionable, and reliable results you can count on. (siemens-healthineers.com)
  • Even when cardiac troponin levels detected by high-sensitivity assays are within the normal range, elevations are associated with incident cardiovascular events in people without overt disease, a meta-analysis confirms. (tctmd.com)
  • Adding information from high-sensitivity troponin assays to models that included conventional risk factors improved prediction of cardiovascular events, particularly fatal ones, suggesting a possible role for the tests in a primary prevention setting, the researchers say. (tctmd.com)
  • Although cardiac troponins have been measured for years for diagnosing acute MI, the introduction of high-sensitivity assays-including just recently in the United States -has allowed for detection of very low levels, even in people without obvious signs of myocardial damage or cardiovascular disease. (tctmd.com)
  • With the introduction of high-sensitivity cardiac troponin (hs-cTn) assays, the time it takes to detect signs of myocyte necrosis has shortened considerably. (bmj.com)
  • We report analytical data from a fully automated digital immunoassay for cardiac troponin I (cTnI) based on Single Molecule Array (Simoa) technology with a limit of detection 2 logs lower than contemporary high sensitivity troponin assays. (quanterix.com)
  • Ninety-Minute vs 3-h Performance of High-Sensitivity Cardiac Troponin Assays for Predicting Hospitalization for Acute Coronary Syndrome. (lifelabs.com)
  • These changes were instituted following the introduction of increasingly sensitive and precise troponin assays. (medscape.com)
  • Two different reference ranges are used in troponin assays. (medscape.com)
  • Troponins are generally undetectable in healthy patients, although this may eventually change as more sensitive assays become available. (medscape.com)
  • The 99th percentile of a reference decision limit (medical decision cutoff) for cardiac troponin (cTn) assays should be determined in each local laboratory with internal studies using the specific assay that is used in clinical practice or validating a reference interval that is based on findings in the literature. (medscape.com)
  • Table 1 shows the calculated 99th upper reference limit values for some of the available troponin assays. (medscape.com)
  • When measured with older generation assays, elevated troponin levels can be detected 6-12 hours after onset of myocardial injury, peaking at about 24 hours, followed by a gradual decline over several days (up to 2 weeks). (medscape.com)
  • Most patients who have had a heart attack have increased troponin levels within 6 hours. (medlineplus.gov)
  • The US Food and Drug Administration (FDA) has approved the Architect Stat (Abbott Laboratories) high-sensitivity troponin-I assay, which can detect myocardial infarction (MI) faster and more accurately than other troponin tests, according to the company. (medscape.com)
  • The addition of Abbott's high sensitivity troponin-I assay to the laboratory's diagnostic testing menu is a great step forward to help laboratory scientists and clinicians better evaluate patients suspected of having a heart attack," Fred Apple, PhD, professor of laboratory medicine and pathology at the University of Minnesota in Minneapolis, said in the release. (medscape.com)
  • A recent publication has shown that cardiac troponin T (TnT) concentrations measured with a highly sensitive assay were significantly associated with the incidence of cardiovascular death and heart failure in stable coronary artery disease after adjustment for other independent prognostic indicators [ 13 ]. (hindawi.com)
  • Hs-cTnI levels were measured using the ARCHITECT STAT High-Sensitivity Troponin-I assay in blood samples collected pre-angiogram. (acc.org)
  • With the increased clinical utility of sub-99th percentile hs-cTn measurements, quality controls with lower cardiac troponin concentrations are needed to monitor and validate hs-cTn assay performance. (clpmag.com)
  • 99thpercentiles for cardiac troponin assay methods addressed in this article are greater than their respective assay methods' LoB, LoD, and LoQ. (clpmag.com)
  • Hear the results of their studies, how transitioning to a high-sensitivity troponin I assay impacted their labs, and the realized benefits to patients and hospitals. (siemens-healthineers.com)
  • Discover how a study in Italy has validated the high-sensitivity troponin I assay as an essential tool for one diagnostic laboratory. (siemens-healthineers.com)
  • Dr. Antonio Buno, La Paz University Hospital, has been working to transform the delivery of cardiac care by implementing a high-sensitivity Troponin I assay. (siemens-healthineers.com)
  • These videos are part of a series of educational videos focusing on the clinical utility of high-sensitivity troponin I. Hear other leaders in the area of cardiovascular disease and laboratory diagnostics discuss implementing a high-sensitivity troponin I assay into their facility. (siemens-healthineers.com)
  • It is unclear if a high-sensitivity troponin assay will have enough discriminative power to become a decision support in primary care. (altmetric.com)
  • The aim of this study was to evaluate a high-sensitivity troponin T assay performed in three primary health care centres in southeast Sweden and to compare the outcome with a point-of-care troponin T test. (altmetric.com)
  • With growing interest in exploring as an early indicator of adverse heart health trends, the ability to quantitate troponin in healthy control populations is emerging as a highly desirable assay capability. (quanterix.com)
  • The 99th percentile cutoff point for cardiac troponin T (cTnT) is well-known at 0.01 ng/mL (with 10% coefficient of variance value at the 99th percentile of 0.03 ng/mL), as only one cTnT assay exists. (medscape.com)
  • Hs-troponin I (Siemens), TNIH assay, was measured using the Siemens Centaur XP. (cdc.gov)
  • For hs-troponin T (Roche) and hs-troponin I (Ortho), low values were initially blinded for each assay. (cdc.gov)
  • Inside the cardiac troponin complex the strongest interaction between molecules has been demonstrated for cTnI - TnC binary complex especially in the presence of Ca2+ ( KA = 1.5 × 10−8 M−1). (wikipedia.org)
  • It has been demonstrated that stability of cTnI in native complex is significantly better than stability of the purified form of the protein or the stability of cTnI in artificial troponin complexes combined from purified proteins. (wikipedia.org)
  • The purpose of this study was to evaluate whether high-sensitivity cardiac troponin I (hs-cTnI) in patients with undergoing angiography for suspected CAD is associated with MI or CV death. (acc.org)
  • Patients with hs-cTnI levels above the 99% URL were four times more likely to experience MI or CV death compared to those with troponin concentrations below 5 ng/L, and improved risk discrimination. (acc.org)
  • In patients undergoing coronary angiography for suspected coronary artery disease (CAD), do high-sensitivity cardiac troponin I (hs-cTnI) levels improve risk stratification for the primary outcome of myocardial infarction (MI) or cardiovascular (CV) death at follow-up? (acc.org)
  • Cardiac troponins (cTn), cardiac troponin I (cTnI) and cardiac troponin T (cTnT), are important analytes for acute myocardial infarction diagnosis and are used to guide treatment and patient management decisions. (clpmag.com)
  • Under 2020 och 21 införs inom Region Skåne en ny högkänslig blodprovsanalys för troponin I (hs-cTnI) som kan avslöja hjärtskada eller hjärtinfarkt. (lu.se)
  • Phosphorylation levels of cardiac troponin I (cTnI) were determined by Western blot. (cdc.gov)
  • We aimed to assess the relationship between LAP burden and circulating levels of high-sensitivity cardiac troponin T (hs-cTnT), and to explore the potential underlying etiology in patients undergoing clinically indicated coronary CT angiography (CCTA). (physiciansweekly.com)
  • The primary aim of this study was to determine optimal thresholds of preoperative and perioperative changes in high-sensitivity cardiac troponin T (hs-cTnT) to predict MACCE and mortality. (lu.se)
  • The use of troponin T (cTnT) and N-terminal Pro-BNP (NTpBNP) in combination with echocardiography assessment may facilitate the development of a superior predictive model. (bmj.com)
  • Measurements of cardiac-specific troponins I and T are extensively used as diagnostic and prognostic indicators in the management of myocardial infarction and acute coronary syndrome. (wikipedia.org)
  • The role of cardiac troponins as diagnostic biomarkers of myocardial injury in the context of acute coronary syndrome (ACS) is well established. (nih.gov)
  • The measurement of cardiac troponins, either cardiac troponin I or T, has become the culprit of clinical decision making in patients with suspected acute coronary syndrome (ACS), especially in those with non-ST elevation myocardial infarction (NSTEMI). (srce.hr)
  • Elevated troponin in acute ischemic stroke - a matter of debate? (eso-stroke.org)
  • With respect to high prognostic relevance, 1 international guidelines recommend the measurement of troponin in all patients presenting with acute ischemic stroke. (eso-stroke.org)
  • 2 However, high-sensitivity troponin is elevated in 20-55% of acute stroke patients, 3 many of whom without thrombotic acute coronary syndrome (ACS). (eso-stroke.org)
  • Why is troponin elevated in so many acute stroke patients? (eso-stroke.org)
  • This question was addressed by the Troponin Elevation in Acute Ischemic Stroke (TRELAS) study, which included 2123 consecutive patients presenting with acute ischemic stroke, who did not have ST-segment-elevation myocardial infarction (STEMI). (eso-stroke.org)
  • 5 Nonetheless, coronary culprit lesions were identified in 24% of stroke patients with elevated troponin, thus demonstrating that elevated troponin should not be ignored in acute stroke patients. (eso-stroke.org)
  • The recently launched Prediction of Acute Coronary Syndrome in Acute Ischemic Stroke (PRAISE) study aims to develop a diagnostic algorithm that allows the prediction of acute coronary syndrome in stroke patients with elevated troponin. (eso-stroke.org)
  • For the time being, a clear recommendation for acute stroke patients with elevated troponin is lacking. (eso-stroke.org)
  • So, elevated troponin in acute ischemic stroke remains a matter of debate! (eso-stroke.org)
  • Jensen JK, Atar D, Mickley H. Mechanism of troponin elevations in patients with acute ischemic stroke. (eso-stroke.org)
  • Coronary Angiographic Findings in Acute Ischemic Stroke Patients With Elevated Cardiac Troponin: The Troponin Elevation in Acute Ischemic Stroke (TRELAS) Study. (eso-stroke.org)
  • By employing a high-sensitivity Troponin I test, laboratory scientists led by Dr. Katell Peoc'h from Paris Diderot University Hospital have been able to more rapidly and accurately diagnose those suffering from acute cardiac events. (siemens-healthineers.com)
  • Troponin T - contemporary approach towards diagnosing acute myocardial ischemia. (medline.ru)
  • We have researched a possibility to apply the Enzyme Multiplied Immunoassay Technique (EMIT-test) for Troponin T to diagnose death resulting from the acute myocardial ischemia in the biological laboratory of the Leningrad Regional Bureau of Forensic Medical Examination. (medline.ru)
  • It means that Troponin T lends itself most widely for a diagnosis uniting the advantages of the quick and slow markers with the acute myocardial ischemia. (medline.ru)
  • Background Patients presenting with acute chest pain without a rise in cardiac troponins are considered to be at low risk of adverse cardiac events and are often considered for early discharge without further inpatient investigation. (bmj.com)
  • However, the further risk stratification of patients presenting with acute chest pain without a rise in cardiac troponin is inconsistent. (bmj.com)
  • Rapid rule-out of acute myocardial infarction with a single high-sensitivity cardiac troponin T measurement below the limit of detection. (bmj.com)
  • The value of high-sensitivity troponin I in the assessment of patients with suspected acute coronary syndrome (ACS) has been well established in clinical practice guidelines. (siemens-healthineers.com)
  • See also Acute coronary syndromes Two subtypes of troponin (cardiac troponin I and T) are very sensitive and specific indicators of damage to the heart muscle ( myocardium ). (wikidoc.org)
  • Up to 80% of patients with acute MI will have an elevated troponin level within 2-3 hours of emergency department (ED) arrival, versus 6-9 hours or more with CK-MB and other cardiac markers. (medscape.com)
  • Recognizing that cardiac troponin measurements may be elevated in disease states not primarily related to myocardial ischemia, a fourth universal definition of acute MI was developed by the American College of Cardiology (ACC), European Society of Cardiology (ESC), American Hospital Association (AHA), and World Health Federation (WHF) in 2018. (medscape.com)
  • Some labs use different measurements (for example, "high sensitivity troponin test") or test different samples. (medlineplus.gov)
  • Cite this: FDA Clears Architect Stat High-Sensitivity Troponin Test for MI - Medscape - Oct 02, 2019. (medscape.com)
  • Serum cardiac troponin I and cardiac troponin T concentrations in dogs with gastric dilatation-volvulus. (vin.com)
  • Very low concentrations of hs-troponin are associated with greater variability and are not routinely reported for clinical use. (cdc.gov)
  • The main difference is that the TnC subunit of troponin in skeletal muscle has four calcium ion-binding sites, whereas in cardiac muscle there are only three. (wikipedia.org)
  • The TnT subunit of troponin binds to tropomyosin-t form, a troponin-tropomyosin complex, anchored in place by the binding of TnI to actin, within muscle thin filaments. (thermofisher.com)
  • The actual amount of calcium that binds to troponin has not been definitively established. (wikipedia.org)
  • citation needed] Troponin is a component of thin filaments (along with actin and tropomyosin), and is the protein complex to which calcium binds to trigger the production of muscular force. (wikipedia.org)
  • citation needed] Individual subunits serve different functions:[citation needed] Troponin C binds to calcium ions to produce a conformational change in TnI Troponin T binds to tropomyosin, interlocking them to form a troponin-tropomyosin complex Troponin I binds to actin in thin myofilaments to hold the actin-tropomyosin complex in place Smooth muscle does not have troponin. (wikipedia.org)
  • A TROPONIN complex subunit that binds calcium and help regulate calcium-dependent muscle contraction. (nih.gov)
  • Troponin is a component of thin filaments (along with actin and tropomyosin ), and is the protein to which calcium binds to accomplish this regulation. (wikidoc.org)
  • Three types of troponins exist-troponin I, troponin T, and troponin C. Each subunit has a unique function: Troponin T binds the troponin components to tropomyosin, troponin I inhibits the interaction of myosin with actin, and troponin C contains the binding sites for Ca 2+ that helps initiate contraction. (medscape.com)
  • Serum troponin (Tn) elevation is a specific and well-established necrosis biomarker in ACS, being the only biomarker currently used for risk stratification and guided invasive management decision in non-STEACS [ 8 , 9 ]. (hindawi.com)
  • It has been shown that even very small elevation in the troponin concentration is associated with increased risk of adverse outcomes in patients with ACS [ 12 ]. (hindawi.com)
  • The level of troponin is measured in the bloodstream and it is used to differentiate between unstable angina (no elevation of troponin, the myocardium is not irreversibly damaged) versus either non ST elevation MI or ST elevation MI (heart attack) in patients with chest pain . (wikidoc.org)
  • For example, patients with elevated troponin levels but negative CK-MB values who were formerly diagnosed with unstable angina or minor myocardial injury are now reclassified as non-ST-segment elevation MI (NSTEMI), even in the absence of diagnostic electrocardiographic (ECG) changes. (medscape.com)
  • however, elevation of troponin levels can occur in myriad conditions other than ischemic damage. (medscape.com)
  • An initial small elevation occurs when troponins are released from the cytosolic pool, when troponin molecules in the cytosol of cardiac muscle diffuse across the sarcolemma into the surrounding lymphatics and blood vessels, becoming detectable in blood. (medscape.com)
  • Troponin C1 is a BIOMARKER for damaged or injured CARDIAC MYOCYTES and mutations in troponin C1 gene are associated with FAMILIAL HYPERTROPHIC CARDIOMYOPATHY. (nih.gov)
  • The aim of this study was to evaluate the potential utility of genetic diagnosis in clinical management of families with hypertrophic cardiomyopathy (HCM) caused by mutations in the gene for cardiac troponin I (TNNI3). (nih.gov)
  • Mutations in the Cardiac Troponin I gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM). (thermofisher.com)
  • Cardiac troponins are components of the contractile apparatus of cardiomyocytes and are released during myocardial necrosis in patients with ACS [ 7 ]. (hindawi.com)
  • For PCI in patients with normal baseline troponin values, elevations of cardiac biomarkers above the 99th percentile upper reference limit indicate periprocedural myocardial necrosis. (medscape.com)
  • If the injury persists and necrosis progresses, further troponins are released from the muscular pool. (medscape.com)
  • Having normal troponin levels 12 hours after chest pain has started means a heart attack is unlikely. (medlineplus.gov)
  • The purpose of this study was to examine whether the combination of two simple tests, electrocardiography (ECG) and serum troponin I (TnI) level, may serve as reliable predictors of BCI or the absence of it. (unboundmedicine.com)
  • Cardiac Troponin-I was measured in serum by ELISA. (bmj.com)
  • Serum values of cardiac troponin T in normal and cardiomyopathic dogs, Vet. (vin.com)
  • Blood troponin levels may be used as a diagnostic marker for stroke or other myocardial injury that is ongoing, although the sensitivity of this measurement is low. (wikipedia.org)
  • A troponin test measures the levels of troponin T or troponin I proteins in the blood. (medlineplus.gov)
  • Cardiac troponin levels are normally so low they cannot be detected with most blood tests. (medlineplus.gov)
  • Very high levels of troponin are a sign that a heart attack has occurred. (medlineplus.gov)
  • Troponin levels may remain high for 1 to 2 weeks after a heart attack. (medlineplus.gov)
  • The Architect Stat test detects very low levels of troponin, allowing clinicians to assess patients with suspected MI within 2 to 4 hours of admission, the company said. (medscape.com)
  • Women may particularly benefit from this technology as they often have lower levels of troponin than men, which could lead to an undiagnosed heart attack with contemporary troponin tests," they add in a news release . (medscape.com)
  • The aim of this study is to investigate myocardial damage in recovering coronavirus disease 2019 (COVID-19) patients with high-sensitivity troponin levels (hsTnT) and echocardiography. (go.jp)
  • Numerous studies have identified a relationship between troponin levels and first-ever cardiovascular events in the general population, so Willeit and colleagues set out to provide an overall estimate of the association. (tctmd.com)
  • Even though we see this very strong association of troponin levels with cardiovascular risk, it still is unclear and remains unknown how we would potentially modify that risk and how we would change our approach based on having a troponin laboratory value as part of your usual clinical assessment," she said. (tctmd.com)
  • First, there are no primary prevention trials similar to those done for statins to show that targeting patients with elevated troponin levels can improve outcomes. (tctmd.com)
  • There's also uncertainty about the source of the raised troponin levels in people without clinically apparent disease. (tctmd.com)
  • Violin plots show distribution of expression levels for Troponin I (SMED30021982) in cells (dots) of each of the 12 neoblast clusters. (stowers.org)
  • Violin plots show distribution of expression levels for Troponin I (SMED30021982) in cells (dots) of each of the 10 clusters of sub-leathally irradiated X1 and X2 cells. (stowers.org)
  • Associations of High-Sensitivity Troponin and Natriuretic Peptide Levels With Outcomes After Intensive Blood Pressure Lowering: Findings From the SPRINT Randomized Clinical Trial. (bvsalud.org)
  • Importance Elevated high- sensitivity cardiac troponin T (hscTnT) and N-terminal pro- B-type natriuretic peptide (NTproBNP) levels are associated with risk of heart failure (HF) and mortality among individuals in the general population . (bvsalud.org)
  • sensitivity cardiac troponin T and NTproBNP levels were measured from stored specimens collected at enrollment, with elevated levels defined as 14 ng/L or more for hscTnT (to convert to micrograms per liter, multiply by 0.001) and 125 pg/mL or more for NTproBNP (to convert to nanograms per liter, multiply by 1.0). (bvsalud.org)
  • N-terminal B-type natriuretic peptide or troponin elevations, or the Background use of inotropes during admission, are much more powerful and Risk stratification and prediction is an integral part of clinical accurate predictors than admission to hospital alone. (who.int)
  • They note that the current diagnostic criteria for perioperative myocardial infarction /injury "need to be updated with these high-sensitivity cardiac troponin data. (medscape.com)
  • The aim of this article is to provide an update on commercially available HS and "ultra"-sensitive techniques for measuring cardiac troponins, along with possible implications of increasingly enhanced analytical sensitivity on diagnostic algorithms for evaluating patients with suspected ACS. (srce.hr)
  • 5 Of all included patients, a subset of 29 of 291 patients with elevated troponin underwent diagnostic coronary angiography. (eso-stroke.org)
  • The total level and the dynamic of the troponin increase may help to predict myocardial infarction, 6 but eventually, the diagnostic work up and treatment of individual patients remains a matter of debate between neurologists and cardiologists. (eso-stroke.org)
  • The EMIT-test for Troponin T - a protein of the myocardial troponin complex - is nowadays of the great diagnostic value. (medline.ru)
  • Conclusions The use of troponin as a diagnostic test and risk stratification tool appears to be used universally in England. (bmj.com)
  • Discussions of troponin often pertain to its functional characteristics and/or to its usefulness as a diagnostic marker for various heart disorders. (wikidoc.org)
  • A laboratory's strategy to reduce the time from "order to result" of high-sensitivity troponin, defined as an imprecision level (%CV) of ?10% at the 99th percentile of normal by the joint ESC/ACC committee, is discussed. (clpmag.com)
  • Troponin C1 is skeletal and cardiac type whereas troponin C2 is skeletal type. (nih.gov)
  • Troponin T was analysed by a point-of-care test and a high-sensitivity method together with N-terminal pro-B-type natriuretic peptide (NT-proBNP) and creatinine. (altmetric.com)
  • Cardiovascular and non‐cardiovascular death distinction: the utility of troponin beyond N‐terminal pro‐B‐type natriuretic peptide. (gla.ac.uk)
  • The best model to predict CV death included low blood pressure, estimated glomerular filtration rate ≤ 60 mL/min, peripheral oedema, previous HF hospitalization, ischaemic HF, chronic obstructive pulmonary disease, elevated N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), and troponin (c‐index = 0.73). (gla.ac.uk)
  • Interpretation of troponin results must be in combination with a full assessment of the clinical context. (bjcardio.co.uk)
  • Univariate and multivariate logistic regression was carried out to examine possible connections between troponin T ≥ 15 ng/L, clinical variables and laboratory findings at baseline. (altmetric.com)
  • The cardiac troponins, in particular, have become the cardiac markers of choice for patients with ACS, eclipsing CK-MB and myoglobin in terms of clinical value. (medscape.com)
  • Troponin is attached to the protein tropomyosin and lies within the groove between actin filaments in muscle tissue. (wikipedia.org)
  • Cardiac Troponin I (Cardiac-specific troponin I, TnI, Troponin I) is an integral inhibitory protein in cardiac muscle that exists as part of a complex with troponin C (TnC) and troponin T (TnT). (thermofisher.com)
  • The gene for the sarcomeric thin-filament protein, slow skeletal muscle troponin T (TNNT1), maps to this interval and was sequenced. (clinicforspecialchildren.org)
  • Troponins are protein molecules that are part of cardiac and skeletal muscle. (medscape.com)
  • The meta-analysis included 28 prospective studies with a total of 154,052 participants free from cardiovascular disease who underwent high-sensitivity troponin testing. (tctmd.com)
  • That more than three-quarters of participants without obvious cardiovascular disease have detectable troponin is "pretty striking," she added. (tctmd.com)
  • Ultra-sensitive cardiac troponin measurement offers a promising new tool for early detection and monitoring of cardiovascular disease. (quanterix.com)
  • Troponin, or the troponin complex, is a complex of three regulatory proteins (troponin C, troponin I, and troponin T) that are integral to muscle contraction in skeletal muscle and cardiac muscle, but not smooth muscle. (wikipedia.org)
  • Troponin is found in both skeletal muscle and cardiac muscle, but the specific versions of troponin differ between types of muscle. (wikipedia.org)
  • The troponins are regulatory proteins found in skeletal and cardiac muscle. (medscape.com)
  • Perioperative myocardial injury, reflected by release of high-sensitivity cardiac troponin T, is associated with 30-day mortality after various cardiac surgeries at postoperative prognostic cutoffs higher than proposed in current definitions, new research suggests. (medscape.com)
  • High-sensitivity cardiac troponin. (nih.gov)
  • High-Sensitivity Cardiac Troponin for Risk Assessment in Patients With Chronic Coronary Artery Disease. (acc.org)
  • High-sensitivity cardiac troponin at 3 hours: is the cat among the pigeons? (whiterose.ac.uk)
  • This webinar will cover the utilization of high-sensitivity cardiac troponin (cTn) in the emergency department (ED) and its impact when delivered via a rapid point of care device or core laboratory. (siemens-healthineers.com)
  • The results for high-sensitivity cardiac troponin in this data release are reported in nanograms per liter (ng/L). (cdc.gov)
  • If a patient is troponin positive, and has signs and symptoms of ischemic heart disease (substernal chest pain or pressure, electrocardiographic EKG changes), then an early invasive strategy is warranted. (wikidoc.org)
  • In the HiSTORIC study, for example, of more than 30,000 consecutive patients, a single cardiac troponin measurement using the test safely and effectively ruled out MI at presentation. (medscape.com)
  • Therefore, the management of stroke patients with elevated troponin is a common matter of debate between neurologists and cardiologists in emergency rooms. (eso-stroke.org)
  • 4 Beyond, elevated troponin in stroke patients might be attributable to nonischemic myocyte injury due to catecholamine-mediated myocardial toxicity, cytokine-mediated myocardial injury, endothelial dysfunction and microvascular spasms. (eso-stroke.org)
  • Is troponin suitable to predict ACS in stroke patients? (eso-stroke.org)
  • What's the ideal management of stroke patients with elevated troponin? (eso-stroke.org)
  • The adoption of a troponin standard for the definition of MI in 2000 increased the incidence of MI by approximately 15%, 2 and undoubtedly identified more high-risk patients for whom aggressive management would be beneficial. (bjcardio.co.uk)
  • It also means that the concept of a 'negative' troponin becomes relatively meaningless as troponin at some level can almost always be detected even in healthy patients. (bjcardio.co.uk)
  • In addition, 21 patients with troponin T ≥ 15 ng/L and no signs of AMI or UA were followed up for 2-3 years. (altmetric.com)
  • Fourteen of the 21 patients, without signs of AMI or UA at baseline, still had increased troponin T at follow-up after 2-3 years. (altmetric.com)
  • Some of this calcium attaches to troponin, causing a conformational change that moves tropomyosin out of the way so that the cross bridges can attach to actin and produce muscle contraction. (wikidoc.org)
  • However, the skeletal and cardiac subforms for TnI and troponin TnT are distinct, and immunoassays have been designed to differentiate between them. (medscape.com)
  • One of the more common uses of troponin is to determine if a patient with chest pain has sustained death of the myocytes (heart muscle cells) as a result of thrombotic (blood clot related) occlusion of a coronary artery which would warrant urgent medical or interventional therapy. (wikidoc.org)
  • The following product was used in this experiment: Cardiac Troponin I Monoclonal Antibody (1D5D6), CoraLite®Plus 488 from Thermo Fisher Scientific, catalog # CL488-66376. (thermofisher.com)
  • 4 Further conditions frequently associated with elevated troponin include atrial fibrillation, heart failure, pulmonary embolism, sepsis, and renal insufficiency. (eso-stroke.org)
  • Troponin is a simple yet potent tool for risk stratification. (wikidoc.org)
  • Some of this calcium attaches to troponin, which causes it to change shape, exposing binding sites for myosin (active sites) on the actin filaments. (wikipedia.org)
  • When asked about the most likely mechanisms to explain the link between modestly elevated troponins and cardiovascular events, Willeit pointed to subclinical coronary atherosclerosis, cardiac stress, and cardiac abnormalities that have not yet been detected. (tctmd.com)
  • Low-attenuation coronary plaque burden and troponin release in chronic coronary syndrome: A mediation analysis. (physiciansweekly.com)
  • Canine Cardiac Troponin I Significantly Complements Established Prognostic Composite Score In Dogs With Systemic Inflammation. (ku.dk)
  • Even a slight increase in the troponin level will often mean there has been some damage to the heart. (medlineplus.gov)
  • Willeit agreed, saying more research, including meta-analyses with patient-level rather than study-level data, needs to be performed before making any recommendations regarding expansive troponin testing. (tctmd.com)
  • Troponin T appears in blood a little earlier that CK-MB, two and a half hours after the onset of the heart attack, reaches its maximum in 8-10 hours (the first peak) and in 3-4 days (the second peak), and its level becomes standard in 10-14 days. (medline.ru)
  • The standard level of Troponin T must be close to zero because it should not get into the blood flow with healthy people. (medline.ru)