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Inotrope
An inotrope or inotropic is a drug or any substance that alters the force or energy of muscular contractions. Negatively inotropic agents weaken the force of muscular contractions. Positively inotropic agents increase the strength of muscular contraction. The term ''inotropic state'' is most commonly used in reference to various drugs that affect the strength of contraction of heart muscle. However, it can also refer to pathological conditions. For example, enlarged heart muscle can increase inotropic state, whereas dead heart muscle can decrease it. Medical uses Both positive and negative inotropes are used in the management of various cardiovascular conditions. The choice of agent depends largely on specific pharmacological effects of individual agents with respect to the condition. One of the most important factors affecting inotropic state is the level of calcium in the cytoplasm of the muscle cell. Positive inotropes usually increase this level, while negative inotro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dobutamine
Dobutamine is a medication used in the treatment of cardiogenic shock (as a result of inadequate tissue perfusion) and severe heart failure. It may also be used in certain types of cardiac stress tests. It is given by IV only, as an injection into a vein or intraosseous as a continuous infusion. The amount of medication needs to be adjusted to the desired effect. Onset of effects is generally seen within 2 minutes. It has a half-life of two minutes. This drug is generally only administered short term, although it may be used for longer periods to relieve symptoms of heart failure in patients awaiting heart transplantation. Common side effects include a fast heart rate, an irregular heart beat, and inflammation at the site of injection. Use is not recommended in those with idiopathic hypertrophic subaortic stenosis. It primarily works by direct stimulation of β1 receptors, which increases the strength of the heart's contractions, leading to a positive inotropic effect. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levosimendan
Levosimendan ( INN) is a calcium sensitizer used in the management of acutely decompensated congestive heart failure. It is marketed under the trade name Simdax ( Orion Corporation). Overall the drug has a two fold mechanism of action. It leads to greater inotropy by increasing the calcium sensitivity as it binds to troponin and this results in a greater positive inotrophic force. Secondly, the drug is able to open ATP-sensitive potassium channels in vascular smooth muscle cells, and the vascular dilatory effects of the drug lead to a decreased preload and afterload, putting less work on the heart. This drug is in the process of review by the FDA but has not been approved for use in the United States yet. Mechanism of action Levosimendan is a calcium sensitizer — it increases the sensitivity of the heart to calcium, thus increasing cardiac contractility without a rise in intracellular calcium. Levosimendan exerts its positive inotropic effect by increasing calcium sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasopressors
An antihypotensive, also known as a vasopressor, is an agent that raises blood pressure by constricting blood vessels, thereby increasing systemic vascular resistance. This is different from inotropes which increase the force of cardiac contraction. Some substances do both (e.g. dopamine, dobutamine). If low blood pressure is due to blood loss, then preparations increasing volume of blood circulation—plasma-substituting solutions such as colloid and crystalloid solutions (salt solutions)—will raise the blood pressure without any direct vasopressor activity. Packed red blood cells, plasma or whole blood should not be used solely for volume expansion or to increase oncotic pressure of circulating blood. Blood products should only be used if reduced oxygen carrying capacity or coagulopathy is present. Other causes of either absolute (dehydration, loss of plasma via wound/burns) or relative ( third space losses) vascular volume depletion also respond, although blood products a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Scientific Vocabulary
International scientific vocabulary (ISV) comprises scientific and specialized words whose language of origin may or may not be certain, but which are in current use in several modern languages (that is, translingually, whether in naturalized, loanword, or calque forms). The name "international scientific vocabulary" was first used by Philip Gove in '' Webster's Third New International Dictionary'' (1961). As noted by David Crystal, science is an especially productive field for new coinages. It is also especially predisposed to immediate translingual sharing of words owing to its very nature: scientists working in many countries and languages, reading each other's latest articles in scientific journals (via foreign language skills, translation help, or both), and eager to apply any reported advances to their own context. Instances According to ''Webster's Third'', "some ISV words (like haploid) have been created by taking a word with a rather general and simple meaning from o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T-type Calcium Channel
T-type calcium channels are low voltage activated calcium channels that become inactivated during cell membrane hyperpolarization but then open to depolarization. The entry of calcium into various cells has many different physiological responses associated with it. Within cardiac muscle cell and smooth muscle cells voltage-gated calcium channel activation initiates contraction directly by allowing the cytosolic concentration to increase. Not only are T-type calcium channels known to be present within cardiac and smooth muscle, but they also are present in many neuronal cells within the central nervous system. Different experimental studies within the 1970s allowed for the distinction of T-type calcium channels (transient opening calcium channels) from the already well-known L-type calcium channels (Long-Lasting calcium channels). The new T-type channels were much different from the L-type calcium channels due to their ability to be activated by more negative membrane potentials, h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical, L-DOPA, which is synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons (nerve cells) to send signals to other nerve cells. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, and many addictive drugs increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in motor control and in controllin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catecholamine
A catecholamine (; abbreviated CA), most typically a 3,4-dihydroxyphenethylamine, is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a substituent of a larger molecule, where it represents a 1,2-dihydroxybenzene group. Catecholamines are derived from the amino acid tyrosine, which is derived from dietary sources as well as synthesis from phenylalanine. Catecholamines are water-soluble and are 50% bound to plasma proteins in circulation. Included among catecholamines are epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine. Release of the hormones epinephrine and norepinephrine from the adrenal medulla of the adrenal glands is part of the fight-or-flight response. Tyrosine is created from phenylalanine by hydroxylation by the enzyme phenylalanine hydroxylase. Tyrosine is also ingested directly from dietary prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossils of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name comes from Latin ''calx'' " lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharmaceuticals for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berberine
Berberine is a Quaternary ammonium cation, quaternary ammonium salt from the protoberberine group of benzylisoquinoline alkaloids, occurring naturally as a secondary metabolite in some plants including species of ''Berberis'', from which its name is derived. Due to their yellow pigmentation, raw ''Berberis'' materials were once commonly used to dye wool, leather, and wood. Under ultraviolet light, berberine shows a strong yellow fluorescence, making it useful in histology for staining heparin in mast cells. As a natural dye, berberine has a Colour Index International, color index of 75160. Biological sources The following plants are biological sources of berberine: * ''Berberis vulgaris'' (barberry) * ''Berberis aristata'' (tree turmeric) * ''Berberis thunbergii'' * ''Fibraurea tinctoria'' * ''Mahonia aquifolium'' (Oregon grape) * ''Hydrastis canadensis'' (goldenseal) * ''Xanthorhiza simplicissima'' (yellowroot) * ''Phellodendron amurense'' (Amur cork tree) * ''Coptis chinensis'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digoxin
Digoxin (better known as digitalis), sold under the brand name Lanoxin among others, is a medication used to treat various heart disease, heart conditions. Most frequently it is used for atrial fibrillation, atrial flutter, and heart failure. Digoxin is one of the oldest medications used in the field of cardiology. It works by increasing myocardial contractility, increasing stroke volume and blood pressure, reducing heart rate, and somewhat extending the time frame of the Muscle contraction, contraction. Digoxin is taken by mouth or by intravenous, injection into a vein. Digoxin has a half life of approximately 36 hours given at average doses in patients with normal renal function. It is excreted mostly unchanged in the urine. Common side effects include gynecomastia, breast enlargement with other side effects generally due to an excessive dose. These side effects may include loss of appetite, nausea, trouble seeing, confusion, and an Heart arrhythmia, irregular heartbeat. Gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiomyopathy
Cardiomyopathy is a group of primary diseases of the heart muscle. Early on there may be few or no symptoms. As the disease worsens, shortness of breath, feeling tired, and swelling of the legs may occur, due to the onset of heart failure. An irregular heart beat and fainting may occur. Those affected are at an increased risk of sudden cardiac death. As of 2013, cardiomyopathies are defined as "disorders characterized by morphologically and functionally abnormal myocardium in the absence of any other disease that is sufficient, by itself, to cause the observed phenotype." Types of cardiomyopathy include hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular dysplasia, and Takotsubo cardiomyopathy (broken heart syndrome). In hypertrophic cardiomyopathy the heart muscle enlarges and thickens. In dilated cardiomyopathy the ventricles enlarge and weaken. In restrictive cardiomyopathy the ventricle stiffens. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Septic Shock
Septic shock is a potentially fatal medical condition that occurs when sepsis, which is organ injury or damage in response to infection, leads to dangerously low blood pressure and abnormalities in cellular metabolism. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) defines septic shock as a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone. Patients with septic shock can be clinically identified by requiring a vasopressor to maintain a mean arterial pressure of 65 mm Hg or greater and having serum lactate level greater than 2 mmol/L (>18 mg/dL) in the absence of hypovolemia. This combination is associated with hospital mortality rates greater than 40%. The primary infection is most commonly caused by bacteria, but also may be by fungi, viruses or parasites. It may be located in any part of the body, but m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
