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[Breeding of a biotype of the aphia Myzus persicae on a synthetic medium. IV. Influence of vitamins, especially vitamin C and pyridoxine, on the nutritional value of nutritive fluids].

The nutritive value of synthetic diets for Myzus persicae was evaluated by measuring reproduction of the third generation on each medium: 1. In the presence of a double dose of pyridoxin, the nutritional value of the basic diet was improved. This improvement disappeared when all the vitamins of the B group were also at double dose; 2. In the presence of a double dose of ascorbic acid, the nutritional value of all the diets was improved. This improvement was observed for a single or a double dose of pyridoxin and a single or a double dose of all the vitamins of the B group. The beneficial effect of a double dose of pyridoxin was not adding with the beneficial effect of a double dose of ascorbic acid; 3. A double dose of EDTA was detrimental to the aphid but a double dose of ascorbic acid was sparing this detrimental effect. The results are discussed in relation with the nutritional needs in vitamins and the action of the vitamins in the mineral nutrition of the aphid.

Animals↗

[Antioxidant vitamins--significance for preventing cardiovascular diseases. Part 1. Oxidized low-density lipoproteins and atherosclerosis; antioxidant dietary supplementation--vitamin E].

The knowledge that an oxidizing of LDL is necessary for the foam cell formation is in the basis of the so called oxidative hypothesis of atherosclerosis. The role of LDL-oxidation for the atherosclerotic plaque formation, as well as its association with inflammatory processes in the vascular wall, are well established. The important conclusion of this hypothesis is the possible role of the antioxidants attenuating atherosclerotic mechanisms. The advances in studying the principal antioxidant vitamins E, C and beta-carotene effects, revealed a great part of their molecular mechanisms, which are not necessarily antioxidative. The important aspects of the cooperative antioxidant action are revealed too, including the so called tocopherol-mediated peroxidation, suggesting the need of the co-antioxidants for effective antioxidant defense. In the recent years many vitamin antioxidant supplementations are used. The epidemiological results of such supplementation do not always reveal the same beneficial effects as expected theoretically or based on the observations made with diet rich in fruits and vegetables. The present paper generalizes the thought concerning the impact of oxidized LDL in atherosclerosis, as well as mechanisms of action and pharmacokinetics of the most widely used antioxidant vitamins--E, C and beta-carotene, and the perspectives of their usage in cardio-vascular prophylaxy based upon the recent experience in antioxidant vitamin supplementation.

Antioxidants↗

[Vitamin "A" and biological membranes. Nota VI-Fatty acid composition of liver mitochondrial membranes in vitamin A-deficient rats (author's transl)].

The results we obtained in studying the fatty acid composition of erythrocyte stroma on vitamin A-deficient rats, led us to repeat the experiment on liver mitochondrial membranes. Two groups of albino male rats, of the Wistar strain, were fed for 90 days with a balanced and a vitamin A-free diet respectively. The animals were killed, total lipid from the membranes of liver mitochondria were extracted and fatty acids separated by gas-chromatography. It was noticed an increase in the percentage of saturated fatty acids; at the same time, mono and polyunsaturated fatty acids decreased. The results agree with those obtained in rats fed for 30 and 60 days with vitamin A-free diet. This seems to support the interpretation that vitamin A modifies, to some extent, the metabolism of polyunsaturated fatty acids.

Animals↗

Effects of serum vitamin E levels on skin vitamin E levels in dogs and cats.

Skin problems are common in small animal practice. Oxidative stress, or the imbalance between prooxidants and the body's antioxidant defense system, likely plays a role in the development of skin disease. According to this study, increasing amounts of vitamin E in foods for dogs and cats increases serum and cutaneous concentrations of vitamin E. Based on available scientific data, these increases in vitamin E concentration are likely to be beneficial. However, the relationship between increases in serum and skin vitamin E concentrations and the prevention, development, and treatment of skin disease remains to be elucidated by intervention studies.

Animal Feed↗

[Antioxidant vitamins in the treatment and prevention of cardiovascular diseases. Vitamin E].

The hypothesis that antioxidant vitamins may reduce risk of cardiovascular diseases has been the subject of considerable research attention in recent years. Basic research studies have provided evidence of possible mechanisms for an effect of antioxidants on atherosclerosis, and several epidemiological studies have suggested that risk of coronary heart disease may be 20-40% lower among those with high dietary intake and serum levels of antioxidant vitamins, especially of vitamin E. However, large-scale randomized trial haven not supported a benefit of high doses of vitamin E supplementation among a general, well-nourished population.

Antioxidants↗

Morphological changes in the tracheal epithelium of guinea pigs in conditions of "marginal" vitamin A deficiency. A light, scanning- and transmission-electron microscopic study under special breeding conditions appropriate to early vitamin A deficiency.

The aim of the study was to find out the influence of marginal vitamin A deficiency on morphological structures in the tracheobronchial epithelium in guinea pigs. The tracheobronchial epithelium of animals with vitamin A deficiency (n = 15) and control animals (n = 7), kept under optimal laboratory conditions, was evaluated by light and electron microscopy. The cellular ultrastructure was morphometrically analyzed. The height of the respiratory epithelium was slightly increased. The basal cells were arranged in a loose cell band of three to four layers. The quantity of cytofilaments in their cytoplasm was enhanced. Goblet cells were significantly reduced in vitamin A deficiency. There was also a significant decrease in their secretory granules. The number of ciliated cells was almost unchanged. They showed a significant reduction in mitochondria. The kinocilia often contained an atypical structure of the microtubules. Our findings confirm multiple ultrastructural dysplasias in early vitamin A deficiency which may lead to a disturbance of mucociliary clearance.

Animals↗

[Evaluation of water-soluble vitamins in the vitamin preparation Spofavit dragée using reversed-phase HPLC].

A reversed-phase HPLC gradient method with good separation efficiency was developed and validated for the evaluation of water-soluble vitamins in the pharmaceutical preparation Spofavit dragee. Analyses were performed on a C8 column (LiChrospher RP-select B), the mobile phase was a mixture of phosphate buffer with sodium hexanesulphonate and acetonitrile. Detection was at 280 and 210 nm. The method is capable within 7 minutes to evaluate 6 water-soluble vitamins (ascorbic acid, nicotinamide, panthotenate.Ca, pyridoxine.HCl, thiamine.HCl, and riboflavin). All validated parameters of this method are discussed; the developed method appeared robust and suitable for evaluation of water-soluble vitamins in vitamin preparations.

Chromatography, High Pressure Liquid↗

Antioxidant effects of combined vitamins C and E in acute myocardial infarction. The randomized, double-blind, placebo controlled, multicenter pilot Myocardial Infarction and VITamins (MIVIT) trial.

AIMS: There is a large body of evidence that reactive oxygen species (ROS) produced during myocardial ischemia and reperfusion play a crucial role in myocardial damage and endothelial dysfunction. The MIVIT pilot trial was designed to test the effects of antioxidant vitamins C and E on the clinical outcome of patients with AMI. METHODS AND RESULTS: In this randomized, double-blind, multicenter trial, 800 patients (mean age 62) with AMI were randomly allocated to receive, on top of routine medication, one of two treatments: vitamin C (1000 mg/12 h infusion) followed by 1200 mg/24 h orally and vitamin E (600 mg/24 h) or matching placebo for 30 days. Primary end point (composite of in-hospital cardiac mortality, non-fatal new myocardial infarction, VT/VF/asystole, shock/pulmonary edema) occurred less frequently in patients treated with antioxidants (55 [14%] vs 75 [19%], OR 0.82 [95% CI, 0.68-1.00], p=0.048). CONCLUSIONS: This randomized pilot trial shows that supplementation with antioxidant vitamins is safe and seems to positively influence the clinical outcome of patients with AMI. A larger study is warranted to provide further evidence of this promising and inexpensive regimen.

Adult↗

Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group.

A randomised double-blind prevention trial with a factorial design was conducted at 33 centres in seven countries to determine whether supplementation with folic acid (one of the vitamins in the B group) or a mixture of seven other vitamins (A,D,B1,B2,B6,C and nicotinamide) around the time of conception can prevent neural tube defects (anencephaly, spina bifida, encephalocele). A total of 1817 women at high risk of having a pregnancy with a neural tube defect, because of a previous affected pregnancy, were allocated at random to one of four groups--namely, folic acid, other vitamins, both, or neither. 1195 had a completed pregnancy in which the fetus or infant was known to have or not have a neural tube defect; 27 of these had a known neural tube defect, 6 in the folic acid groups and 21 in the two other groups, a 72% protective effect (relative risk 0.28, 95% confidence interval 0.12-0.71). The other vitamins showed no significant protective effect (relative risk 0.80, 95% Cl 0.32-1.72). There was no demonstrable harm from the folic acid supplementation, though the ability of the study to detect rare or slight adverse effects was limited. Folic acid supplementation starting before pregnancy can now be firmly recommended for all women who have had an affected pregnancy, and public health measures should be taken to ensure that the diet of all women who may bear children contains an adequate amount of folic acid.

Abortion, Induced↗

[Vitamin A-vitamin D3 relationship in growing rats].

A relation vitamin A - vitamin D3 exists in diet for growing rats. When this decreases from 5 (microgram A - IU D3) or 15 (IU A - IU D3) to 1,25 (microgram/IU) or 3,75 (IU/IU) growth, calcemia are increasing but vitamin A hepatic storage is decreasing. In other words for a same quantity of retinol, cholecalciferol's level in diet determines hepatic stores of vitamin A. General aspect of this question is discussed.

Animal Nutritional Physiological Phenomena↗

[Vitamin D supplementation in institutionalized elderly. Effects of vitamin D3 (100,000 IU) orally administered every 3 months on serum levels of 25-hydroxyvitamin D].

A clinical trial carried out during the autumn/winter season in 46 institutionalized elderly subjects (35 women, 11 men) (group mean age = 83 +/- 2 years) revealed a severe deficiency in vitamin D in these subjects (25-hydroxyvitamin D level less than or equal to 3 ng/ml). After oral administration of 100,000 IU of vitamin D3, an increase in 25-hydroxyvitamin D levels above the 10 ng/ml threshold was observed and maintained for three months. A second dose, administered after 3 months, made it possible to sustain this level. No sign of toxicity was detected, notably no trace of hypercalcemia. In contrast, no change in the deficit (25-hydroxyvitamin D level less than or equal to 3 ng/ml) was seen in the placebo population. Three-monthly administration of the moderate dosage of 100,000 IU of vitamin D3 all year round would offer a simple, effective and risk-free system to counteract vitamin D deficiency in the elderly and of preventing the risk of osteomalacia, thus reducing the incidence of fractures.

Administration, Oral↗

[Vitamin D-induced tissue calcinosis and arteriosclerosis changes. I: A contribution to the 60 year history of vitamin D research with special reference to childhood].

Already in 1927, a short time after the detection of the vitamin D, the danger of a hypervitaminosis was put into the field of view. Overdoses of vitamin D may effect calciferous infiltrations in the soft tissue and arteriosclerotic changes. These findings are important especially under consideration of the up-to-now large-dosed vitamin-D-application in the field of the rachitis-prophylaxis. The appearance of nephrocalcinoses could have been demonstrated in predisposed infants and children suffering from disorders in calcium metabolism. In order to optimize the rachitis-prophylaxis in the GDR we comment on the problems and dangers by vitamin-D-overdosages on the basis of animal-experimental and clinical examinations.

Arteriosclerosis↗

Effects of dietary vitamin B-2 and vitamin E on the delta9-desaturase and catalase activities in the rat liver microsomes.

The effects of dietary vitamin B-2 and vitamin E on delta9-desaturation of stearoyl-CoA, catalase, glutathione peroxidase, superoxide dismutase and electron transport components in rat liver microsomes have been investigated. delta9-desaturase activities were decreased on diets deficient of vitamin B-2, E and supplemented with E. Among the peroxide-scavenging enzymes, only the catalase activity in microsomes correlates significantly with delta9-desaturase activity. In vitro addition of bovine catalase had no effect on microsomal delta9-desaturase activity on control diet. However, it enhanced the delta9-desaturation in microsomes on vitamin B-2-deficient diet which contained low catalase and high superoxide dismutase activities, compared to those in microsomes of control diet. It is suggested that the hydrogen peroxide-generating and -decomposing systems may play an important role on the delta9-desaturase activity in microsomes.

Animals↗

Vitamin D metabolites in generalized scleroderma. Evidence of a normal cutaneous and intestinal supply with vitamin D.

Vitamin D metabolites in serum were analysed in 20 patients with generalized scleroderma. The concentration of 1,25-dihydroxyvitamin D was normal, however, significantly lower concentrations (p less than 0.05) were found in 7 patients with cutaneous calcinosis in comparison with 13 patients with no calcinosis. Concentrations of 25-hydroxyvitamin D, 24-25-dihydroxyvitamin D, and vitamin D-binding protein (Gc globulin) were all within the normal range. The 24,25-dihydroxy-vitamin D level correlated with the duration of disease (r = 0.4453, p less than 0.05), and 25-hydroxyvitamin D tended to correlate (r = 0.3016, NS). The study strongly indicates that cutaneous synthesis, intestinal absorption and hepatic hydroxylation of vitamin D are not deficient in scleroderma. A relative but specific decrease in the renal hydroxylation to 1,25-dihydroxyvitamin D, i.e. the active hormone, as the disease progresses and calcinosis occurs, is suspected.

Adult↗

[Lipid peroxidation in aged patients. Influence of an antioxidant combination (vitamin C-vitamin E-rutin)].

Lipoperoxidation has an important role in the normal processes of the cell-life. The induction is produced by oxygen-derived free radicals which attack the membrane phospholipids. Such an attack is modulated by an enzymatic protection system (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase) and by a non-enzymatic one (vitamin C, vitamin E...). In various pathologic conditions, a dispoise takes place between radical attack and antiradical protection. The place taken by lipoperoxidation in the ageing process seems to be fundamental. We report here the results of a study carried out in aged and sick patients who were given an antioxidant medicamentous combination made from Vitamin C, Vitamin E and Rutin. Our results evidence that such a synergistic combination does modify both enzymatic protection system and lipoperoxidation, this latter showing a decrease under treatment.

Aged↗

[The vitamin allowance and vitamin requirements of the operators of a chemical plant in the city of Rustavi].

Excretion of thiamine, riboflavin, N1-methyl nicotinamide and ascorbic acid with urine, TDP-effect, ascorbic acid and vitamin A content in the blood have shown higher vitamin requirements in the operators, as compared to subjects of the control group, this was caused by unfavourable effects of the chemical factors of the production environment. The levels of the biochemical parameters characterizing normal providing of the operators with vitamins could be achieved by additional vitamins administered to the workers (2 dragees of "Hexavitum").

Adult↗

Effect of vitamin A supplementation on plasma and breast milk vitamin A levels in poorly nourished Gambian women.

Plasma and breast milk vitamin A and plasma carotenoids were measured in groups of pregnant and lactating women in two neighbouring rural Gambian villages. One of the groups (Keneba) received a 650 micrograms daily vitamin A supplement. During pregnancy, plasma retinol values were significantly (19 per cent) higher in the supplemented group. During lactation, breast milk values were significantly (23 per cent) higher in the supplemented group. Changes in plasma and breast milk vitamin A levels during the cycle of pregnancy and lactation and with season are also described, and the value of a combined index of plasma retinol and plasma carotenoids is illustrated. The significant effect of a prolonged low level vitamin A supplement to pregnant and lactating women has important implications for nutrition intervention programmes.

Adult↗

[Treatment of psoriasis using vitamin A, vitamin A acid and oral retinoids].

Vitamin A, Vitamin A acid (retinoic acid) and their synthetic derivatives were variously applied in the management of psoriasis with different therapeutic results. Obviously, they influence the proliferation rate and the differentiation of human keratinizing epithelia and have beneficial effects on skin diseases with disturbances of keratinization, including psoriasis. Systemic application of Vitamin A has been yet largely abandonned since high dosages leading to clearing develop evident systemic toxicity. The anti-psoriatic effect of Vitamin A acid is either moderate or restricted, because of side effects. Only its combined local application with topical corticosteroids may be considered. Oral application of newly synthesized retinoids, however, was beneficial in psoriasis, particularly in erythrodermic or pustular types. With this group of retinoids new pathways were opened in dermatotherapy which may help to replace cytostatic drugs in these cases. Additionally, oral retinoid treatment may be introduced as an adjuvans in the management of widespread psoriasis, in order to enhance the effect of anthralin, PUVA or UVB treatments.

Female↗