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Scurvy is a disease resulting from a deficiency of vitamin C. Humans and certain animals require vitamin C in their diets for the synthesis of collagen. In infants, scurvy is sometimes referred to as Barlow's disease, named after Sir Thomas Barlow, a British physician who described it in 1883. However, Barlow's disease may also refer to mitral valve prolapse. Other eponyms for scurvy include Moeller's disease and Cheadle's disease. The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, ''scorbutus'', which also provides the adjective scorbutic ("of, characterized by or having to do with scurvy"). Typical symptoms of scurvy are initially fatigue, followed by formation of spots on the skin, spongy gums, and bleeding from the mucous membranes. Spots are most abundant on the thighs and legs, and a person may look pale, feel depressed, and be partially immobilized. As scurvy advances, there can be open, suppurating wounds, loss of teeth, yellow skin, fever, neuropathy and finally death from bleeding. Treatment is by a vitamin C-rich diet, whereby complete recovery from incipient scurvy takes less than two weeks. Vitamin C is widespread in plant tissues, with particularly high concentrations occurring in capsicum fruit (especially sweet green peppers), cruciferous vegetables (such as kale, broccoli and brussels sprouts), and citrus fruits (especially oranges). Organ meats such as liver contain more vitamin C than muscle meat. Cooking significantly reduces the concentration of vitamin C as does exposure to air and copper and other transition metal salts such as those of iron. Scurvy does not occur in most animals as they can synthesize their own vitamin C. However, humans and other higher primates, guinea pigs, most or all bats, and some species of birds and fish lack an enzyme necessary for such synthesis and must obtain vitamin C through their diets. Historically, Hippocrates (c. 460 BC–c. 380 BC) described scurvy, and herbal cures for scurvy have been known in many native cultures since prehistory. Nevertheless, treatment was inconsistent, and scurvy was one of the limiting factors of marine travel, often killing large numbers of the passengers and crew on long-distance voyages. It was a Scottish surgeon in the Royal Navy, James Lind, who first proved it could be treated with citrus fruit in experiments he described in his 1753 book ''A Treatise of the Scurvy'', though following a failed trial with extracted lime juice, it would be 40 years before effective prevention based on fresh produce became widespread.〔(【引用サイトリンク】title=A Brief History of Vitamin C and its Deficiency, Scurvy )〕 Scurvy remained a problem during expeditions and in wartime until the mid-20th century. == Signs and symptoms == Early symptoms are malaise and lethargy. Even earlier might be a pain in a section of the gums which interferes with digestion. After 1–3 months, patients develop shortness of breath and bone pain. Myalgias may occur because of reduced carnitine production. Other symptoms include skin changes with roughness, easy bruising and petechiae, gum disease, loosening of teeth, poor wound healing, and (emotional changes ) (which may appear before any physical changes). Dry mouth and dry eyes similar to Sjögren's syndrome may occur. In the late stages, jaundice, generalized edema, oliguria, neuropathy, fever, convulsions, and eventual death are frequently seen. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「scurvy」の詳細全文を読む スポンサード リンク
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