Anion Health Dictionary

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Anion: From 1 Different Sources

n. an ion of negative charge, such as a bicarbonate ion (HCO3?) or a chloride ion (Cl?) (See also electrolyte). The anion gap is the difference between the concentrations of cations (positively charged ions) and anions, calculated from the formula:

It is used to estimate the unaccounted-for anions in the blood in cases of metabolic disturbance. The normal anion gap is 12–16 mmol/l.

Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Ion

A particle that carries an electrical charge; positive ions are called cations and negative ions are called anions. Many vital body processes, such as the transmission of nerve impulses, depend on the movement of ions across cell membranes. Sodium is the principal cation in the fluid that bathes all cells (extracellular fluid). It affects the flow of water into and out of cells (see osmosis), thereby influencing the concentration of body fluids.

The acidity of blood and other body fluids depends on the level of hydrogen cations, which are produced by metabolic processes. To prevent the fluids from becoming too acidic, hydrogen cations are neutralized by bicarbonate

anions in the extracellular fluid and blood, and by phosphate anions inside cells (see acid–base balance).... ion

Colocasia Esculenta

(Linn.) Schott.

Synonym: C. antiquorum Schott.

Family: Araceae.

Habitat: Cultivated throughout India.

English: Taro, EdibleYam.

Ayurvedic: Pindaaluka, Aaluki.

Siddha/Tamil: Chaembu, Shaeppam- kizhangu.

Folk: Arvi, Ghuiyaa.

Action: Juice from petiole—styptic, rubefacient. Juice of corn—used in alopaecia.

The leaves contain flavones, api- genin and luteolin, also anthocyanins. Leaves cause severe irritation in mouth. Cooked leaves are a source of dietary fibre for diabetics helping in lowering post-prandial blood glucose level. A significant increase in total lipids, total cholesterol and triglyceride levels was observed in hypercholesterolaemic rats when fed with dried leaf powder.

The pressed juice of the petioles is used as an astringent and styptic. All parts of the plant show an acridity. The acridity is removed by boiling and by addition of baking soda.

From the tubers two dihydroxys- terols, besides beta-sitosterol and stig- masterol, have been isolated. Five novel aliphatic compounds have been reported. Trypsin inhibitors are isolated from the tubers.

The total amino acids recorded in the tubers range from 1380 to 2397 mg/ 100 g. The lysine concentration was relatively low. Besides starch, the tubers contain natural polysaccharides with 56% neutral sugars and 40% anionic components. Steamed corms contain 30% starch and 3% sugar.... colocasia esculenta

Hyperlipidaemia

An excess of fat in the blood, characterising a group of metabolic disorders. The two most important fats circulating in the blood are CHOLESTEROL and TRIGLYCERIDE. Raised blood levels of cholesterol predispose to ATHEROMA and coronary artery disease (see HEART, DISEASES OF); raised triglycerides predispose to pancreatitis (see PANCREAS, DISORDERS OF). Six types of hyperlipidaemia have been identi?ed, and diagnosis of the di?erent types depends upon blood tests to discover lipid levels. Some of the hyperlipidaemias are familial, and some are secondary to other diseases such as hypothyroidism (see THYROID GLAND, DISEASES OF), DIABETES MELLITUS, nephrotic syndrome and alcoholism.

Treatment There is evidence that therapy which lowers the lipid concentration reduces the progression of premature atheroma, particularly in those who suffer from the familial disorder. Treatment should include appropriate diets, usually food that is low in cholesterol and saturated fats. There are a number of drugs available for lowering the lipid content of the plasma, but these should be reserved for patients in whom severe hyperlipidaemia is inadequately controlled by weight reduction. Anion-exchange resins – clo?brate, beza?brate and gem?brozil, for example – and statins such as atorvastatin and simvastatin, as well as nicotinic acid, all lower plasma cholesterol and plasma triglyceride concentration through their e?ect on reducing the hepatic production of lipoproteins. Cholestyramine and colestipol, both of which are anion-exchange resins, bind bile salts in the gut and so decrease the absorption of the cholesterol that these bile salts contain – hence lowering plasma cholesterol concentrations. Probucol lowers plasma cholesterol concentrations by increasing the metabolism of low-density lipoproteins.

The statins (atorvastatin, cerivastatin, ?uvastatin, pravastatin and simvastatin) inhibit an enzyme involved in synthesising cholesterol, especially in the liver. They are more e?ective than anion-exchange resins in lowering LDL (low-density lipoprotein) cholesterol – a form of low-density cholesterol carried in the bloodstream, high levels of which are believed to be the main cause of atheroma. Statins are, however, less e?ective than the clo?brate group in reducing triglycerides and raising HDL (highdensity lipoprotein) cholesterol (high-density cholesterol).... hyperlipidaemia

Ion Atom

An atom (or a collection of atoms) that has an electrical charge. Positive atoms are cations, negative ones are anions. Calcium, hydrogen, potassium and sodium are positive ions. Negative ones include bicarbonate chloride and phosphate. All the substances are critical to the body’s physiological activities.... ion atom

Ion Exchange Resins

Synthetic organic substances, capable of exchanging ions – cationic or anionic – from the contents of the intestine. Originally used in the prevention of OEDEMA, they have been superseded in this role by the modern DIURETICS, and are now used chie?y in the treatment of HYPERKALAEMIA. They are usually taken by mouth or as an ENEMA.... ion exchange resins

Lipid-regulating Drugs

These drugs reduce the amount of low-density LIPOPROTEINS, which transport CHOLESTEROL and triglycerides (see TRIGLYCERIDE) in the blood, or raise the concentration of high-density lipoproteins. The aim is to reduce the progression of ATHEROSCLEROSIS and therefore help prevent coronary heart disease (see HEART, DISEASES OF). These drugs should be combined with reducing other risk factors for raised lipid concentrations, such as a high-fat diet, smoking and obesity. Lipid-regulating drugs include STATINS, ?brates, anion-exchange resins, and NICOTINIC ACID, which may be used singly or in combination under careful medical supervision (see HYPERLIPIDAEMIA).... lipid-regulating drugs

Cation

n. an ion of positive charge, such as a sodium ion (Na+). Compare anion. See electrolyte.... cation

Osmolar Gap

the difference between the measured serum osmolality and the calculated osmolality using the following formula:

It is an aid to the diagnosis of severe *anion gap acidoses. The normal range for the difference is ± 10 mOsm/kg. A high osmolar gap is normally due to the presence of acetone, mannitol, or an alcohol.... osmolar gap

Electrolyte

n. a solution that produces ions (an ion is an atom or group of atoms that conduct electricity); for example, sodium chloride solution consists of free sodium and free chloride ions. In medical usage electrolyte usually means the ion itself; thus the term serum electrolyte level means the concentration of separate ions (sodium, potassium, chloride, bicarbonate, etc.) in the circulating blood. Concentrations of various electrolyte levels can be altered by many diseases, in which electrolytes are lost from the body (as in vomiting or diarrhoea) or are not excreted and accumulate (as in renal failure). When electrolyte concentrations are severely diminished they can be corrected by administering the appropriate substance by mouth or by intravenous drip. When excess of an electrolyte exists it may be removed by *dialysis or by special resins in the intestine, taken by mouth or by enema. See also anion.... electrolyte

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