Selenium posioning may be acute (short-term) or chronic (long-term). The effects of acute selenium poisoning depend upon the route of exposure.
Acute inhalation exposure to selenium (usually in the form of selenium dioxide or hydrogen selenide) primarily results in respiratory effects with irritation of the mucous membranes in the nose and throat, producing coughing, nosebleeds, dyspnea (difficulty breathing), bronchial spasms, bronchitis, and chemical pneumonia. There may also be gastrointestinal effects including vomiting and nausea; cardiovascular effects; neurological effects such as headaches and malaise; and irritation of the eyes.
Acute oral exposure to selenium compounds results in pulmonary edema and lesions of the lung; cardiovascular effects such as tachycardia; gastrointestinal effects including nausea, vomiting, diarrhea, and abdominal pain; effects on the liver; and neurological effects such as aches, irritability, chills, and tremors.
Chronic (long-term) exposure to high levels of selenium in food and water results in discoloration of the skin, deformation and loss of nails, reversible loss of hair (baldness), excessive tooth decay and discoloration, a garlic odor to the breath, weakness, lack of mental alertness, and listlessness.
An amino acid in which selenium takes the place of sulfur in the amino acid cysteine. Its formula is H-Se-CH2-CH(NH2)-COOH. Selenocysteine is an essential component of selenium-containing proteins, or selenoproteins.
A peculiar class of proteins that contain the essential trace element selenium. The selenium in these proteins is in the amino acid selenocysteine.
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“autos” (self) and “phobos” (fear) = literally, self-fear, fear of oneself. “Autos” has given us many English words such as “automatic” and “automotive” (self-moving) and “autonomy” (self-governing). And “phobos” has bequeathed us a vast number of phobias such as “claustrophobia” (fear of closed places) and “acrophobia” (fear of heights).
- Selfish operon
A hypothesis according to which the clustering of genes and their subsequent organization into operons is beneficial to the constituent genes because it enables the transfer of functionally coupled genes, genes involved in the same biosynthetic pathway. The selfish operon hypothesis may or may not prove true in microbial genetics but it is surely not […]
- Sciatic nerve
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