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

Serum and liver ceruloplasmin levels rose markedly in guinea pigs with acute scurvy and with chronic latent scurvy. Their increase in the former condition can be attributed to the general stress reaction, but the increase in ceruloplasmin levels in concentration may have a stimulant effect on the ceruloplasmin, when the oxidation of Fe2+ to Fe3+ is potentiated, may obstruct the binding of iron to protoporphyrin and prevent formation of the haeme of cytochrome P 450 and b5.
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PMID:Acute and chronic vitamin C deficiency in guinea-pigs: its effect on ceruloplasmin and cytochrome P 450 and b5 levels. 621 11

Vitamin C (ascorbic acid) has been known to prevent scurvy for many years. Recent research has shown its importance in lipid and iron metabolism. Vitamin C may also have some effect on the immune system. There is not as yet conclusive evidence that ascorbic acid may cure or prevent colds or cancer. The vitamin has few side effects even when ingested in large quantities. Several methods for analysis of ascorbic acid have been developed. These include titration and fluorometric methods, a ferrozine technique automated for centrifugal analyzers, a high performance liquid chromatography method, and a dip-stick for urine ascorbic acid.
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PMID:Vitamin C: from scurvy to the common cold. 634 85

Plasma vitamin C was measured in 885 patients in a psychiatric hospital and in 110 healthy controls. The average value was lower in the patients (0.51 mg/100 ml) than in the controls (0.87 mg/100 ml). Length of stay in hospital had little effect on plasma vitamin C in the patients, but the values were marginally lower in males, females on iron therapy and in those with senile dementia. In the patients, many of whom had been offered a similar diet for several years, age was not associated with a change in plasma vitamin C and this suggests that changes in vitamin C with age that have been reported reflect differences in intake. Few patients had values as low as those found in clinical scurvy (less than 0.1 mg/100 ml), but many (32 per cent) had concentrations below the threshold (0.35 mg/100 ml) at which some detrimental effects on health have been reported.
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PMID:Plasma vitamin C concentrations in patients in a psychiatric hospital. 666 28

The incidence of ascorbic acid (AA) deficiency and its effect on serum ferritin concentration relative to body iron stores was studied in 61 unchelated patients with beta-thalassaemia major. Thirty-nine (64%) of patients had subnormal leucocyte ascorbate concentrations without clinical evidence of scurvy. The lowest leucocyte ascorbate concentrations tended to occur in the most transfused patients. No correlation was found between the units transfused and serum ferritin concentration in the AA-deficient patients but a close correlation (r = +0.82; p less than 0.005) existed for the AA-replete group. Similarly a close correlation (r = +0.77; p less than 0.005) was obtained between liver iron concentration and serum ferritin in AA-replete patients but only a weak correlation (r = +0.385; p less than 0.025) existed for the AA-deficient group. When AA-deficient patients were treated with ascorbic acid, serum iron and percentage saturation of iron binding capacity rose significantly; serum ferritin rose in 13 of 21 patients despite the simultaneous commencement of desferrioxamine therapy. In contrast all three measurements tended to fall in AA-replete patients with ascorbic acid and desferrioxamine therapy. Thus, AA deficiency is commonly present in beta-thalassaemia patients with iron overload and may give rise to inappropriate serum ferritin concentrations in relation to body iron stores.
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PMID:Effect of ascorbic acid deficiency on serum ferritin concentration in patients with beta-thalassaemia major and iron overload. 708 92

There is an enormous amount of literature on vitamin C intake and health in animals, cell cultures, and humans. Beyond its function in collagen formation, ascorbic acid is known to increase absorption of inorganic iron, to have essential roles in the metabolism of folic acid and of some amino acids and hormones, and to act as an antioxidant. In recent years, research has increasingly focused on this latter function, stimulated by suggestions that "oxidative stress" may be a causal factor in the etiology of such diverse and important disorders of aging as cancer, cardiovascular disease, and cataract formation. The present evidence is strong enough to have convinced nutritionists that daily vitamin C intake should be many times higher than the amount needed to protect against scurvy, and this is reflected in the present Recommended Dietary Allowances. Suggestions that the recommended levels should be higher still are largely based on extrapolations from results of animal and tissue culture studies. How much ascorbic acid is necessary to achieve in humans the effects seen in animal studies is not clear. In general, the limited human studies have not been persuasive. The data are incomplete, and many of the studies have serious flaws. There are no toxicity studies of the type done for new compounds being considered for approval as therapy for major disease conditions. Intervention studies will be difficult, but are essential, and methods for tissue saturation measurement must be defined before new recommendations for the public are designed.
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PMID:Vitamin C (ascorbic acid): new roles, new requirements? 805 61

Up to the mid-1960s, beta-thalassemia was treated with blood transfusions as frequent as needed to keep symptoms under control and to prevent transfusional hemosiderosis. In the following years, high transfusion regimens and iron chelation therapy with desferrioxamine were used. Because of these different treatment modalities, skeletal findings in thalassemia have markedly changed. In the past, thalassemic patients treated with a low transfusion regimen and without chelation therapy developed osteopenia--with widened medullary spaces, cortical thinning and trabecular atrophy--secondary to chronic expansion of red marrow, due to increased erythropoietin response to chronic anemic hypoxia. Typical radiographic patterns in the skull included widened diploic space, atrophic-especially outer--tables and, in some patients, the "hair-on-end" pattern. As for the face, obliteration of the paranasal sinuses and the typical "rodent facies" were observed. In the ribs, bulbous expansion of the posterior and anterior segments and the "rib within a rib" patterns were observed. As for the spine, coarse trabecular arrangement was seen. The "cobweb" pattern was seen in the pelvis and finally the lack of the normal concave outline was observed in the long bones. In the patients treated with high transfusion regimens and iron chelation therapy over the last 30 years, both skull anomalies and disfigurement are less frequent. The skull is almost normal, with the exception of osteopenia and thickened diploic space in the frontal bone only; the paranasal sinuses are usually not obliterated. The hands and rib are normal, just like long bones, pelvis, scapulae and vertebral bodies. Nevertheless, in some adequately treated patients new skeletal features have been recently observed in the long bones, which are similar to those occurring in rickets and/or scurvy, and in the vertebral bodies, resembling platyspondylia. These abnormal features might be caused by several factors--i.e., marrow expansion, transfusion regimens, direct/indirect effects of desferrioxamine, iron load, endocrine abnormalities, deficiency of some minerals and finally dysvitaminoses. Nevertheless, osteopenia remains the main negative factor of thalassemia.
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PMID:[The evolutionary effects of therapy on the skeletal lesions in beta-thalassemia]. 819 Sep 18

The regulation of expression of hepatic iron-related proteins was examined during iron deficiency caused by scurvy in guinea pigs. Previous studies showed that some effects of scurvy, such as suppression of collagen gene expression, result from events associated with weight loss. During the initial phase of scurvy when vitamin C is depleted but animals grow normally, serum iron levels decreased to 50% of normal. During the second phase of scurvy when animals lose weight, there was a further decrease in iron levels to 10-15% of normal. Serum transferrin levels increased during scurvy, but this increase was related neither to the rate of weight loss nor to hepatic transferrin mRNA expression, which decreased. Serum ferritin levels of diminished early in scurvy with a preferential loss of the L subunit. In liver, however, both ferritin animals gaining weight. Ferritin gene expression during vitamin C deficiency was correlated with serum ferritin levels in that the level of mRNA for the H subunit remained relatively constant while that of the L subunit decreased early. Transferrin receptor mRNA expression in liver was induced as soon as iron levels decreased early in scurvy, which is similar to results reported for iron-depleted cultured cells. In contrast to results in cell culture, expression of iron regulatory protein 1 mRNA was decreased to approximately 50% of normal early in scurvy with a concomitant decrease in hepatic cytosolic aconitase activity. Our data indicate that iron deficiency occurs early during vitamin C deficiency and leads to changes in expression of iron-related proteins that differ in some aspects from regulation by iron in cell culture. Other events associated with weight loss in late scurvy may play a further role in this regulation.
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PMID:Gene expression of iron-related proteins during iron deficiency caused by scurvy in guinea pigs. 856 10

The recent scientific literature indicates that beyond merely protecting against scurvy vitamin C contributes to many aspects of human health. The main areas of research reviewed include: 1. Vitamin C requirements of smokers. The data indicate that the vitamin C requirement of smokers is higher by at least 60 mg per day (up to 140 mg per day) than that of nonsmokers. 2. Important functions of the body, such as immune response, pulmonary function, and iron absorption are related to vitamin C intakes. Daily vitamin C intake of at least 150-200 mg per day enhance these functions. 3. Vitamin C may play critical roles in the prevention of CHD, cancer and cataract. Based on the available data, vitamin C intakes of at least 80-120 mg per day are associated with lowering the risk of these chronic diseases. 4. The literature documents that these and much higher intake levels of vitamin C are safe.
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PMID:Vitamin C and human health--a review of recent data relevant to human requirements. 869 41

African iron overload has been recognised in sub-Saharan Africa for seventy years. The condition is distinct from the well-characterised HLA-linked haemochromatosis described in Caucasians. Increased dietary iron intake predisposes to the condition. Recent evidence suggest that African iron overload may be caused by an interaction between increased dietary iron and a genetic defect not associated with the HLA-locus. Iron deposition is prominent both in macrophages and in hepatic parenchymal cells. Iron overload is distinct from alcoholic liver disease, although the excess dietary iron is derived from a traditional beverage that contains alcohol. African iron overload has clinical consequences. It is a cause of hepatic fibrosis and cirrhosis, and associations with diabetes mellitus, peritonitis, scurvy and osteoporosis have been described. African iron overload may be a cause of hepatocellular carcinoma. The disorder is associated with a poor outcome in tuberculosis, an infection that is highly prevalent in sub-Saharan Africa.
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PMID:African iron overload. 1088 73

This article focuses on the differential diagnosis of pathologic lesions recorded on the limbs and crania of 17 subadults from two pre-European burial mounds in Tonga, western Polynesia. All affected subadults were between the ages of 6 months and 3 years at death. The lesions described consist primarily of subperiosteal new bone deposition on the limbs and endocranial surface. However, the presence of cribra orbitalia in a number of individuals indicates concurrent iron-deficiency anaemia. A differential diagnosis of haematogenous osteomyelitis, congenital syphilis, yaws, scurvy, hypervitaminosis A, trauma, Caffey's disease, and iron-deficiency anaemia is discussed. It was concluded that the most likely cause for the lesions observed is a synergistic relation between infection (weanling diarrhoea, yaws) and metabolic disease (scurvy and possibly hypervitaminosis A). Trauma is not ruled out as contributing to the development of some pathologic lesions. It is concluded that, in the Pacific Islands at least, multiple causes for skeletal pathology in subadults should be considered rather than a single aetiology.
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PMID:Subadult health and disease in prehistoric Tonga, Polynesia. 1110 83


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