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Query: UMLS:C0036474 (scurvy)
 685 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes of the phosphofructokinase (PFK; KF.2.7.I.II) activity in the skeletal and heart muscle, in the liver and skin of guinea pigs with different ascorbic acid allowances of their organism were studied. In animals receiving physiological and high vitamin "C" doses no changes in the activity of the tissues under study were observed. In cases of acute C-hypovitaminosis the activity of the enzyme in the skin fell by 26 per cent, in scurvy it declined in the liver by 28 per cent and in the skin -- by 46 per cent. In these conditions the PFK activity in the skeletal and heart muscles remained invariable. In one group of the animals chronic latent C-hypovitaminosis was simulated it attended by a diminishing fermentative activity in the heart by 24 and in the skin -- by 20 per cent. No changed activity in the liver was revealed.
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PMID:[Activity of phosphofructokinase in some organs of guinea pigs with different ascorbic acid levels]. 12 99

There is a certain presumptive evidence for believing than AA has functions other than the simple prevention of classical scurvy; whether these extra-antiscorbutic functions are attributable to AA itself, or to one or more of its metabolites, is not known. Tissue saturation with AA would appear to provide a good insurance against defects in these extra-antiscorbutic areas. ttissue saturation is attainable by a daily intake of 100-150 mg in man; there are no compelling reasons for using megadoses of AA and the emphasis should be on the avoidance of chronic hypovitaminosis C. There is suggestive evidence that megadoses of AA could be physiologically disadvantageous--particularly with regard to in-utero exposure and in persons exposed to high environmental levels of toxic metals.
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PMID:Nonscorbutic effects of vitamin C: biochemical aspects. 87 Aug 97

The authors report the case a 11-month-old baby girl admitted by the "Mother and Child Welfare" doctor. On admission, she was very hypotrophic, febrile and pale. Furthermore, she had anaemia complicated with painful invalidating oedema of both thighs. X-ray film show moderate lesions of the metaphysis, but very rapidly, there was a hugh bilateral sub-periosteal hematoma. They insist on the value of periosteal hematoma as a characteristic sign of scurvy. This was later confirmed by laboratory investigations and by the finding of urinary infection due to bilateral reflex on cystography and to right uretero-hydronephrosis on I.V.P. This case is singular because it associates three findings: severe vitamin deficiency by dietetic error due to modern industrial alimentation and a major urinary tract malformation with refractory urinary tract infection.
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PMID:[Osseous scurvy in an 11-month-old infant. Radiological course]. 117 97

With a normal and varied food intake, the vitamin supply is often sufficient to avoid vitamin deficiency. Since synthetic vitamins have become available, it has become possible to take with one dose the amount of vitamins normally taken up from food in one year. In these pharmacological doses vitamins must therefore be considered as drugs. And in pharmacological doses, their actions are often different and not directly linked to their physiological activity. Two types of pathologic state are unquestionably the concern of vitaminotherapy: More or less specific and intense vitamin deficiencies: Rickets, scurvy, beri beri, pellagra, vitamin deficiency related to alcohol consumption, polyneuritis, encephalopathy, malabsorption, mucoviscidosis, etc. Genetic defects of vitamin metabolism: Prescriptions for these cases represent only a tiny part of the vitamin pharmaceutic market. The prescription of vitamins as adjuvants in other pathologic states without vitamin deficiency, such as neurological pains, psychosis, prevention of common cold, alopecia, anemia, asthenia, carpal tunnel defect, etc., is frequent. The results may be good; however, in some cases, the efficacy is due to chance or placebo effect, and there is no scientific or experimental evidence of beneficial activity. At the moment, the pharmacological vitamin research is very active. New products with vitamin-like structures are being synthesized for specialized therapeutic applications. They will in the near future probably replace elevated and mega-doses for clinical prescription, except, of course, for the treatment of vitamin deficiency. On the other hand, the use of multivitamin preparations in nutritional dosage will greatly increase.
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PMID:Clinical conditions requiring elevated dosages of vitamins. 250 93

1. After the administration of labelled proline to guinea pigs deprived of ascorbic acid for 15 days, the dorsal skin was examined 5 days later in an attempt to detect the presence of hydroxyproline-deficient collagen (protocollagen). The extent of incorporation of proline into skin collagens indicated a severe impairment of collagen synthesis. 2. A comparison of proline and hydroxyproline specific radioactivities in diffusible peptides obtained by treatment with collagenase of either purified skin collagens or direct hot-trichloroacetic acid extracts of skin failed to indicate the presence of protocollagen. Possible reasons for this are discussed. 3. The incorporation results did not indicate an inability of normal collagen, i.e. collagen hydroxylated to the normal degree, to cross-link in scurvy. 4. Incorporation of labelled proline into aortic elastin isolated from the same animals did not indicate a decrease in elastin biosynthesis in ascorbic acid deficiency, beyond that attributable to the inanition accompanying the vitamin deficiency. The proline/hydroxyproline specific-radioactivity ratio in elastin from scorbutic guinea pigs was about 6:1 in contrast with the 1:1 ratio in control groups. It is concluded that the formation of elastin hydroxyproline was ascorbate-dependent and that a hydroxyproline-deficient elastin is formed and retained in scurvy. The formation of desmosines was unimpaired in scorbutic animals. 5. Studies with chick embryos confirmed the formation of elastin hydroxyproline from free proline. Incorporation of free hydroxyproline into elastin hydroxyproline was negligible. 6. Digestion of solubilized samples with collagenase indicated that the hydroxyproline in guinea-pig aortic elastin preparations was not derived from contamination by collagen. It is suggested that most if not all of the hydroxyproline in the guinea pig elastin preparations investigated can be considered an integral part of the elastin molecule.
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PMID:Studies in vivo on the biosynthesis of collagen and elastin in ascorbic acid-deficient guinea pigs. 430 21

Plasma and buffy-coat vitamin C were estimated in 158 samples from 139 lung-cancer patients, at all stages of the disease. Most samples showed hypovitaminosis C in both estimations: 64% had plasma, and 25% buffy-coat values below the thresholds for incipient clinical scurvy (0.3 mg% and 10 micrograms/10(8) cells respectively). Levels were diet-dependent and could be increased by oral supplements. Levels were low both in tumour-bearing patients and in those clinically free of disease after resection. The latter had particularly low values during the first 6 months, indicating the utilization of vitamin C in surgical repair. The vitamin C content of 13 primary lung tumours was assayed: tumours had a higher vitamin C content (mean 111.6 +/- 55.1 micrograms/g tissue) than normal lung (58.5 +/- 20.4 micrograms/g). Mononuclear cells from normal individuals show a higher vitamin C content than polymorphs, but in lung-cancer patients the expected correlation of buffy-coat vitamin C with the proportion of lymphocytes in peripheral blood was obscured by an inverse correlation in patients with relative lymphocytosis (greater than or equal to 25% lymphocytes), confirmed by an inverse correlation of the proportion of lymphocytes in peripheral blood with mononuclear-cell vitamin C in 14 patients in whom this was measured. These correlations were unaffected by controlling for plasma values, and indicate the utilization of vitamin C in lymphocyte-related anti-tumour mechanisms. Vitamin C is necessary for phagocytosis and for the expression of cell-mediated immunity. In view of the increasing circumstantial evidence that immune mechanisms exert some measure of control on tumour extension and metastasis in man, the effect of supplementation with vitamin C in lung-cancer patients on survival should be tested in a clinical trial.
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PMID:Severe hypovitaminosis C in lung-cancer patients: the utilization of vitamin C in surgical repair and lymphocyte-related host resistance. 712 25

Tissue ascorbic acid (AA) contents of approximately 12 and 100% saturation respectively were produced in two groups of guinea-pigs. The 'low-AA' group had a significantly lower muscle carnitine concentrations than the 'high-AA' group. There was no concomitant emergence of the symptoms customarily regarded as characteristic of hypovitaminosis C. It is concluded that muscle carnitine (beta-OH-gamma-(trimethyl-amino)butyric acid) is a highly-sensitive indicator of tissue AA contents; this could account for the lassitude and fatique reported to precede the emergence of frank scurvy in man.
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PMID:Dietary ascorbic acid and muscle carnitine (beta-OH-gamma-(trimethylamino) butyric acid) in guinea-pigs. 737 44

Mucocutaneous changes occur in vitamin deficiency states and may be helpful in clinical diagnosis of the underlying disease. Substitution and therapy with vitamins can also cause skin problems, which may be of allergic of nonallergic origin. The skin and mucosal changes in pellagra and scurvy can be diagnostic; however, in other vitamin deficiencies, skin signs are rather unspecific. In most cases combined vitamin deficiencies occur that result in polymorphic and nonspecific mucocutaneous signs. Vitamin deficiencies are due to malnutrition, malabsorption or genetic defects. In industrialized countries alcoholism and gastrointestinal disorders are the main cause of vitamin deficiencies. Alcoholics or patients with malabsorption syndrome suffering from seborrheic dermatitis-like or ichthyosiform-like eruptions should be investigated for vitamin deficiency. Laboratory analysis of blood and urine vitamin levels can be misleading because of the poor correlation with tissue vitamin concentrations. Rapid clinical improvement following vitamin substitution frequently confirms the clinical diagnosis. In this overview we describe mucocutaneous signs of vitamin deficiencies. Excellent reviews of this topic are recommended for further reading [1-5].
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PMID:[Vitamins and skin]. 807 86

Vitamin A deficiency is frequent in the tropics. It causes xerophthalamia, which, in severe cases, can develop into corneal ulceration, keratomalacia and blindness and increases morbidity and mortality of infectious diseases in infants and children. Vitamin A deficiency can be reduced by the promotion of a nutrition rich in vitamin A, by fortification of food with vitamin A and by high-dose vitamin A supplementation. Other vitamin deficiency disorders are rare or occur only in limited areas or in disadvantaged people. In refugee camps, scurvy, beriberi, pellagra and xerophthalamia occur. Travelers from developed countries are rarely affected by vitamin deficiency disorders, if they eat regularly the large variety of fruits and vegetables usually available in tropical countries. Their vitamin stocks are anyhow sufficient for several weeks.
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PMID:[Vitamin deficiency in developing countries]. 807 89

Vitamin deficiency syndromes such as scurvy and beriberi are uncommon in Western societies. However, suboptimal intake of some vitamins, above levels causing classic vitamin deficiency, is a risk factor for chronic diseases and common in the general population, especially the elderly. Suboptimal folic acid levels, along with suboptimal levels of vitamins B(6) and B(12), are a risk factor for cardiovascular disease, neural tube defects, and colon and breast cancer; low levels of vitamin D contribute to osteopenia and fractures; and low levels of the antioxidant vitamins (vitamins A, E, and C) may increase risk for several chronic diseases. Most people do not consume an optimal amount of all vitamins by diet alone. Pending strong evidence of effectiveness from randomized trials, it appears prudent for all adults to take vitamin supplements. The evidence base for tailoring the contents of multivitamins to specific characteristics of patients such as age, sex, and physical activity and for testing vitamin levels to guide specific supplementation practices is limited. Physicians should make specific efforts to learn about their patients' use of vitamins to ensure that they are taking vitamins they should, such as folate supplementation for women in the childbearing years, and avoiding dangerous practices such as high doses of vitamin A during pregnancy or massive doses of fat-soluble vitamins at any age.
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PMID:Vitamins for chronic disease prevention in adults: clinical applications. 1206 76


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