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PubMed1986

[Vitamin status of 11- to 17-year-old healthy adolescents. Data from a longitudinal study].

In order to find out whether any age- or sex-related changes in vitamin nutrition or if any vitamin deficiencies can be detected in apparently healthy school children, blood vitamins (A, B1, B2, B6, C, and E) were determined in 111 children (54 boys and 57 girls), who took part in a longitudinal nutritional program. Most of the adolescents were examined yearly 5 times every year and afterwards two years later; at the begin of the study their age was 11 years, at the end 17 years. The results of vitamin determinations show for the most parameters age dependent changes, levels for Vitamin A, B1, and B2 becoming higher with increasing age, for Vitamin C in contrast markedly unfavorable. Using the criteria for risk for deficiency from adults a comparatively high percentage of adolescents must be considered to be at risk for deficiency (up to 30% for Vitamin B6). As this study shows partly statistically significant correlations between growth and some vitamin levels (e.g., for Vitamin A and E), age and sex related criteria for the assessment of vitamin status in adolescents should be made available. The results in general show that also in apparently healthy school-children subclinical biochemical vitamin deficiencies can be detected. This fact however, should be taken in consideration in planing and providing guidelines for an optimal nutritional program in adolescence.

Adolescent↗

PubMed1979

Vitamin C deficiency in guinea pigs: variable sensitivity of collagen at different sites.

1. The synthesis of collagen in several tissues, including the C1q component of complement in serum, was measured in vitamin C-deficient and control guinea pigs by incorporating labelled proline into hydroxyproline in vivo. 2. Of the tissues examined, by far the greatest specific effect of vitamin C deficiency was observed in skin. Bone was second in order of sensitivity; skeletal muscle, lung, heart and kidney exhibited only small effects, which were difficult to distinguish from those of inanition, while liver, C1q, and the ethanol-soluble components of serum were virtually insensitive. The effect on urinary hydroxyproline was also extremely small. 3. The lack of sensitivity of C1q confirms previous conclusions (BATES, LEVENE, OLDROYD and LACHMANN 1978), based on total protein bound hydroxyproline levels and total C1 activity in plasma. Since C1q, which turns over rapidly, is insensitive, the high sensitivity of "repair" tissues to vitamin C deficiency is unlikely to be connected with their high turnover rate. Differential concentration of vitamin C by different tissues seems more likely to be the critical factor.

Adrenal Glands↗

PubMed2003

Current studies on oxidant stress in dialysis.

Breath ethane measurements in hemodialysis indicate that a portion of these patients suffer increased oxidant stress, consistent with findings using other methods for oxidant stress determination. Loosely-bound iron definitely appears in the bloodstream when substantial doses of IV iron are administered, since transferrin is fully saturated, but our investigations generally do not show short-term oxidant stress from this treatment. If small doses of IV iron are utilized, transferrin saturation can be avoided, and risk is minimized. The vitamin C status of hemodialysis patients is usually lower than the general population, and the impact of this deficiency must be assessed in controlled investigations. Various interventions, including the vitamin E-bonded dialyzer and dietary antioxidant supplements, may ameliorate a portion of the oxidant stress in hemodialysis patients.

Ascorbic Acid Deficiency↗

PubMedDate not supplied

Comparison of plasma and leukocyte vitamin C status between asthmatic and healthy subjects.

In a case-control study the vitamin C status of 50 adults with chronic controlled asthma was compared with that of 50 randomly selected healthy controls. Vitamin C intake was assessed by 3-day dietary recall, and plasma and leukocyte vitamin C concentrations were measured colorimetrically. A positive significant correlation was found between plasma vitamin C and dietary vitamin C intake. Plasma and leukocyte vitamin C levels were significantly lower in the asthma group. Plasma vitamin C was deficient (< 0.4 mg/dL) in significantly more patients than controls (38.0% versus 0%) and leukocyte vitamin C (< 20 microg/10(8) leukocytes) was deficient in 92.0% of asthmatics versus 8.0% of controls. A significant association was observed between duration of asthma and plasma vitamin C level.

Adult↗

PubMed2004

Treatment of iron deficiency anemia with Ferro-Folgamma.

Iron deficiency anemia is a hypochromic anemia in which hemoglobin poor synthesis is due to a decrease in the amount of iron in the body. The decrease of iron quantity has many causes: insufficient intake of aliments rich in iron (meat, viscera, green vegetables), increased necessities during growth period, pregnancy, erythrocytes hyperregeneration, high-performance sportsmen, increased loss by digestive way, genito-urinary way, respiratory, hemorrhagic syndromes. Clinically, symptoms and signs specific to all types of anemia and those specific to lack of iron occur besides the symptoms and signs of the underlying disease: atrophic glositis, angular stomatitis, sideropenic dysphagia, pica, skin and nails changes. Laboratory investigations useful for diagnosis are: microcytic, hypochromic anemia, decreased serum iron level, total capacity of iron binding increased, medullar iron store absent, good response to iron therapy. Ferro-Folgamma is one of the most indicated medicines in iron deficiency anemia. Due to its components this medicine has many indications: insufficient alimentary intake concerning iron, folic acid, B12 vitamin, vegetarian alimentation, increased needs during growth period, iron deficiency anaemia secondary to chronic hemorrhages, malnutrition, anemias associated with chronic alcohol intake, preventive treatment of iron deficiency anemia and megaloblastic anemia during pregnancy and lactation.

Anemia, Iron-Deficiency↗

PubMed1982

NADPH-dependent reduction of cytochrome P-450 in liver microsomes from vitamin C-deficient guinea pigs: effect of benzphetamine.

The effect of dietary vitamin C on the reduction of cytochrome c and cytochrome P-450 by NADPH-cytochrome P-450 reductase was determined in guinea pig liver microsomes. Acute vitamin C deficiency decreased hepatic microsomal cytochrome P-450 content 21% and the rate of cytochrome P-450 reduction 66% without affecting cytochrome c reduction. However, the vitamin status of the animals did not affect the enhancement in cytochrome P-450 reduction produced by the addition of a type I substrate to the reaction mixture. The results suggest that vitamin C deficiency selectivity affects the transfer of electron from NADPH to cytochrome P-450 and that this effect does not result from a change in the spin state of cytochrome P-450.

Animals↗

PubMed2003

An epidemic of scurvy in Afghanistan: assessment and response.

In March 2002, there were reports of a hemorrhagic fever outbreak in western Afghanistan. It was later confirmed that the hemorrhagic symptoms and increased mortality were actually due to scurvy. Most aid workers did not include scurvy in the initial differential diagnosis because it is uncommon throughout the world and has mainly been reported in refugee populations in recent times. A rapid assessment confirmed the cases clinically, estimated a prevalence rate of 6.3% (a severe public health problem), and determined that the attack rates peaked each year in January and February (the end of the winter). Many Afghans have limited dietary diversity due to isolated locations, lengthy winters, the continuing drought of the last four years, asset depletion, and loss of livelihood. After numerous food and fortification options to prevent future outbreaks had been considered, vitamin C tablet supplementation was selected because of the relatively rapid response time as compared with other prevention methods. A three-month course of vitamin C tablets was distributed to 827 villages in at-risk areas. The tablets were acceptable and compliance was good. No cases of scurvy were reported for the winter of 2002-03. The case study from Afghanistan demonstrates that scurvy can occur in nonrefugee or nondisplaced populations; vitamin C supplementation can be an effective prevention strategy; there is an urgent need to develop field-friendly techniques to diagnose micronutrient-deficiency diseases; food-security tools should be used to assess and predict risks of nutritional deficiencies; and the humanitarian community should address prevention of scurvy in outbreak-prone areas.

Adolescent↗

PubMed1991

[The induction of the monooxygenase system and the incorporation of the radioactive label from 2-14C-lysine into the liver microsome fraction of rats exposed to phenobarbital against a background of deficiencies in lysine, methionine, threonine and vitamins A, C and E].

The effect of diet on induction of monooxygenases and distribution of label from 2-14C-lysine in fractions of liver homogenate, muscle homogenate and blood of male rats treated with phenobarbital (80 mg/kg, three days) was studied. 2-14C-lysine was injected intraperitoneally 24 h before the first injection of phenobarbital. It was demonstrated that monoxygenase induction, increase of relative liver weight and incorporation of label from 2-14C-lysine into fractions of liver homogenate in phenobarbital-treated rats were more pronounced as compared with the similarly treated rats that were fed a balanced diet. The possibility of mobilization of deficient essential components to liver from other organs and tissues for maintenance of monoxygenase induction is discussed.

Amino Acids↗

PubMedDate not supplied

[Effect of lysine, threonine, methionine and vitamin A, C and E deficiency on the liver microsome enzyme system responsible for metabolizing foreign compounds in the rat].

It has been demonstrated that the deficiency of 3 essential amino acids (lysine, threonine and methionine) combined with polyhypovitaminosis A, C and E for 2 months leads to a decrease in the para-hydroxylase and N-demethylase activity in rat liver microsomes. The content of cytochromes P-450 and b5 was also reduced as compared to that in animals given balanced nutrition. However, in such a polynutrient deficiency, the activity of microsomal enzymes was induced by phenobarbital to a greater degree than in balanced nutrition. It is suggested that in polynutrient deficiency, the lacking essential factors mobilized from other organs and tissues are involved in the process of induction of microsomal enzymes.

Amino Acids↗

PubMed1984

Compliance and nutritional status during feasibility study for an intervention trial in China.

As part of a pilot study to assess the feasibility of a long-term intervention trial to be done in Linxian, People's Republic of China, nutritional status and compliance were assessed in villagers taking daily multivitamin pills containing the U.S. Recommended Dietary Allowances (RDA). Before the start of the trial and again during its 4th month, nutritional status was assessed by laboratory tests and a dietary interview. Compliance was assessed in all subjects by pill counts and in a subset by urinary riboflavin loading-dose tests. At the outset of the trial, the study population had widespread biochemical and dietary deficiencies of ascorbic acid and riboflavin. As expected, subjects taking a daily pill had significantly improved status for these vitamins during the study. Compliance as measured by pill counts was excellent, with over 90% of the subjects taking at least 80% of their daily pills. Mean urinary excretion of a riboflavin loading dose entered and remained in the normal range after 3 weeks of supplementation, indicating that compliance did not fall off over time. Compliance was similar in normal subjects and in those with a prior diagnosis of esophageal dysplasia. Compliance also was nearly as good in subjects receiving monthly home visits as in those receiving weekly home visits from the barefoot doctor (village paramedical worker). The results of this pilot study indicated that a long-term intervention trial was feasible in Linxian and that the RDA dose level of vitamins was effective in ameliorating certain nutritional deficiencies prevalent in the study population.

Adult↗

PubMed2001

Vitamin C plasma concentrations and leg weakness in the forelegs of growing pigs.

Four litters (41 pigs) of cross-bred pigs were studied from 6 to 26 weeks of age. Blood samples were collected at 6, 13, 21 and 26 weeks of age and analysed for contents of vitamin C, calcium (Ca), inorganic phosphorus (P) and alkaline phosphatase (ALP). The pigs were examined clinically for foreleg weakness at the ages of 21 and 26 weeks. At the age of 26 weeks the pigs were slaughtered and the right forelegs were examined macroscopically and selected samples were collected for radiological, histological and ultrastructural examination. The prevalence of foreleg lesions was high, with lesions of dyschondroplasia of the distal growth plate of the ulna in 30 pigs, synovitis of the elbow joint in 24 pigs and osteochondritis dissecans of the elbow joint in 25 pigs. At the ages of 21 and 26 weeks, five pigs had evidently crooked forelegs and 14 pigs (age 21 weeks) and 25 pigs (age 26 weeks) had mildly deformed forelegs. The serum levels of Ca, P and ALP were within normal values for growing-finishing pigs. The range of vitamin C concentrations in plasma showed a wide difference (7.1-49.8 mumol/l) but was not associated with deformed forelegs. The serum concentrations of Ca, P and ALP and the plasma concentration of vitamin C differed significantly (P = 0.05) between age groups and there was a significant (P = 0.001) positive correlation between the levels of vitamin C in plasma and the serum levels of ALP at 6 weeks of age. The aim of the present study was to determine if there was any association between the plasma levels of vitamin C and the extent of crooked or deviated forelegs in growing-finishing pigs. We could not find a vitamin C deficiency during the study and no association between low levels of vitamin C in plasma and the presence of deformed forelegs of these 40 pigs.

Animals↗

PubMed1981

Effect of vitamin C deficiency in guinea pigs on intestinal functions and chemical composition of brush border membrane.

The effect of vitamin C deficiency on the digestive and absorptive functions of the gut has been investigated in guinea pigs. The absorption of D-glucose was significantly elevated, but that of L-leucine, L-alanine and L-lysine considerably depressed in the intestine of scorbutic guinea pigs compared to controls. The intestinal transport of vitamin B12 was also diminished. Activities of sucrase and alkaline phosphatase on the brush border were enhanced, but that of leucine aminopeptidase markedly reduced in scorbutic animals compared to controls. Maltase activity was unaffected in vitamin C deficient animals. Chemical analysis of the brush borders isolated from scorbutic animals revealed a considerable decrease in membrane protein, total lipids, phospholipids, and free cholesterol contents compared to control animals. In vivo 2-(14)C-acetate incorporation into membrane lipids suggested that the observed decrease in lipid components of the scorbutic membranes is due to reduced synthesis. Administration of ascorbic acid to scorbutic animals ameliorated the intestinal aberrations observed in scurvy.

Animals↗

PubMedDate not supplied

[Nitrogen metabolism in various forms of protein-vitamin deficiency].

Experiments were made on rats to study the effect of protein deficiency, amino acid unbalance and vitamin B1, A, E, C deficiency on the weight gain of rats, on the eating up of feed, the blood content of nitrogenous components and their excretion with urine and feces. The feeding of the diets deficient in protein, essential amino acids and vitamins leads to substantial changes in nitrogenous metabolism. Such alimentary disorders are followed by the reduced assimilability and biological value of food proteins.

Amino Acids↗

PubMed2006

Effects of vitamin C supplementation on the growth of Heterobranchus longifilis fingerlings.

A 12-week growth experiment was conducted to establish the necessity of vitamin C in the nutrition of Heterobranchus longifilis fingerlings. Vitamin C was supplemented at levels of 0 and 50 mg x kg(-1) to a basal diet (42.5% CP), which was fed to triplicate groups of H. longifilis fingerlings. Fish receiving the vitamin C-supplemented diet had significantly improved weight gain (20.7 vs. 16.7 g per fish), feed efficiency ratio (1.03 vs. 1.42), specific growth rate (3.00 vs. 2.74%), protein efficiency ratio (2.26 vs. 1.64), and survival rate (90% vs. 50%). There was a significant decrease in haematocrit and haemoglobin levels in the blood of fish fed no supplemental vitamin C. Furthermore, this group exhibited retarded growth and pathological changes such as vertebral curvature, condensation associated with fragility of the spinal bones. Supplementation of 50 mg vitamin C per kg diet was adequate to prevent the occurrence of vitamin C deficiency in H. longifilis and it was concluded that vitamin C is essential in the nutrition of these fishes.

Animal Feed↗

PubMed1985

Involvement of water-soluble vitamins in diseases of swine.

The various roles of the water-soluble vitamins (including choline and vitamin C) in diseases of swine are outlined. The most important role is in the prevention of deficiency disease; another important role is in relation to the immune response. Deficiency signs relating to each vitamin are described and the metabolism of each vitamin is outlined. Recent estimates of requirements are set out, together with suggestions on supplementation of practical diets for swine.

Animals↗

PubMed1985

[Course of epilepsy in patients who have suffered adverse effects of anticonvulsant preparations according to the results of long-term follow-up].

The author studied 99 epileptic patients in whom 5-10 years ago anticonvulsants had caused side-effects. In 10% of the patients, a stable remission of the paroxysmal manifestations and an improvement of the mental status was achieved after controlling the complications. The majority of the patients exhibited slow progression of the epileptic process following a reduction of disturbances induced by intoxication and folic acid deficiency. Severe toxic, metabolic and allergic complications (30%) were followed by further considerable progression of the paroxysmal and psychopathological symptomatology. The degree of progression and severity of the organic brain lesion in epileptic patients is an important factor affecting the manifestation of the side-effects associated with anticonvulsants and the efficiency of further anticonvulsive therapy. In 4% of the patients the author observed repeated drug-induced complications. The prophylaxis of repeated complications of the anticonvulsant treatment prevents epilepsy aggravation.

Adolescent↗

PubMed1987

Vitamin C deficiency and low linolenate intake associated with elevated blood pressure: the Kuopio Ischaemic Heart Disease Risk Factor Study.

We investigated the association of dietary fatty acids and plasma antioxidative vitamins with blood pressure in 722 eastern Finnish men aged 54 years, examined in the Kuopio Ischaemic Heart Disease Risk Factor Study in 1984-1986, who had no known hypertension nor any cerebrovascular disease. Allowing for the major anthropometric, dietary, medical and psychological determinants of blood pressure in a multivariate regression analysis, plasma ascorbic acid concentration had a moderate, independent inverse association (P less than 0.0001) and the estimated dietary intake of linolenic acid an inverse (P = 0.026) independent association with mean resting blood pressure. The marked elevation of blood pressure at the lowest levels of plasma vitamin C concentration supports the hypothesis of the role of antioxidants in the aetiology of hypertension.

Ascorbic Acid↗

PubMed2004

Plasma ascorbate deficiency is associated with impaired reduction of sulfamethoxazole-nitroso in HIV infection.

OBJECTIVE: The objective of these studies was to determine the role of ascorbate deficiency in HIV infection in the defective detoxification of sulfamethoxazole-nitroso, the metabolite thought to mediate sulfonamide hypersensitivity reactions. METHODS: Fifty-one HIV-infected patients and 26 healthy volunteers were evaluated. Vitamin supplementation histories were obtained, and blood samples were collected for determination of plasma ascorbate, dehydroascorbate, and cysteine concentrations, erythrocyte glutathione concentrations, and plasma reduction of sulfamethoxazole-nitroso in vitro. RESULTS: Plasma ascorbate concentrations were significantly lower in HIV-positive patients not taking vitamin supplements (29.5 +/- 22.3 microM) than in healthy subjects (54.8 +/- 22.3 microM; P = 0.0005) and patients taking 500-1000 mg of ascorbate daily (82.5 +/- 26.3 microM; P < 0.0001). Plasma ascorbate deficiency was strongly correlated with impaired reduction of sulfamethoxazole-nitroso to its hydroxylamine (r = 0.60, P < 0.0001), and during in vitro reduction, the loss of plasma ascorbate was strongly associated with the amount of nitroso reduced (r = 0.70, P < 0.0001). Ascorbate added ex vivo normalized this reduction pathway. Erythrocyte glutathione concentrations were significantly lower in HIV-positive patients (0.98+/-0.32 mM) than in healthy subjects (1.45+/-0.49 mM; P = 0.001), but this finding was unrelated to ascorbate supplementation. There was trend toward lower plasma cysteine concentrations in patients (8.4+/-3.9 microM) than in controls (10.3+/-4.3 microM), but this trend was similarly unrelated to ascorbate supplementation. Dehydroascorbate concentrations were not significantly higher in HIV-positive patients (7.4+/-10.5%) than in healthy controls (4.0+/-6.2%), even in the subset of patients taking ascorbate (8.4+/-9.4%). CONCLUSIONS: Ascorbate deficiency is common in HIV-positive patients and is associated with impaired detoxification of sulfamethoxazole-nitroso, the suspected proximate toxin in sulfonamide hypersensitivity. Patients taking daily ascorbate supplements (500-1000 mg) achieved high plasma ascorbate concentrations and did not show this detoxification defect. Ascorbate deficiency (or supplementation) was not associated with changes in glutathione or cysteine concentrations. These data suggest that ascorbate deficiency, independent of thiol status, may be an important determinant of impaired drug detoxification in HIV infection.

Adult↗