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Screening method for vitamins A and D in fortified skim milk, chocolate milk, and vitamin D liquid concentrates.

Vitamin A was determined in fortified chocolate milk and skim milk; vitamin D was determined in fortified chocolate milk, skim milk, and vitamin D concentrates, using reverse phase high pressure liquid chromatography (HPLC). The sample is saponified, extracted with hexane, and chromatographed in an HPLC system on a 10 micron Vydac TP reverse phase C18 column, using acetonitrile-methanol (9+1) as the mobile phase. For 6 replicates, the recoveries of vitamins A and D, using this procedure, were 99 and 98%, respectively.

Animals↗

Effect of dietary coconut oil and casein and megadoses of vitamin A or C on tissue lipid peroxidation and hemolysis in vitamin E deficiency.

Male rats fed on pellet diet to an average weight of 105 g were placed on a vitamin E deficient diet containing 20% coconut oil for a period of 12 weeks at two dietary protein levels, 20% and 10% casein. Rats on 20% casein diet showed a definite weight loss but not so at the 10% casein level. A marked increase in the liver in vitro lipid peroxidation was observed at both protein levels. Feeding of retinyl palmitate at 100,000 IU/100 g body weight for 4 consecutive days inhibited the liver, brain and kidney in vitro peroxidation; megadoses of ascorbic acid produced less inhibition of the liver peroxidation, but the same degree of inhibition for brain and kidney peroxidation as in vitamin A loaded rats. Both dietary palmitate or ascorbic acid. Acetylcholine esterase and ATPase, two of the membrane enzymes of erythrocytes, were depressed in all the groups. The glutathione content of erythrocytes was increased in rats given ascorbic acid. In all the groups the higher dietary protein levels produced greater loss of body and tissue weights. It is concluded vitamin E deficient diet supplemented with dietary coconut oil (saturated fat) induces increased in vitro lipid peroxidation and oxidative lysis of erythrocytes and that megadoses of vitamin A or C suppress the in vitro lipid peroxidation but enhance the lysis.

Animals↗

Clinical chemical methods for the routine assessment of the vitamin status in human populations. Part I: The fat-soluble vitamins A and E, and beta-carotene.

Reliable HPLC methods for the routine determination of vitamin A (only retinol, not the ester) of beta-carotene and of vitamin E in plasma are described. The results found in 150 blood donors are reported; the correlation of the concentrations of vitamin A with retinol-binding protein and of vitamin E with beta-lipoproteins are calculated.

Animals↗

Vitamin D deficiency in obese patients and changes in circulating vitamin D metabolites following jejunoileal bypass.

The serum levels of the three major vitamin D metabolites [25-hydroxyvitamin D (25-OHD), 1,25-dihydroxyitamin D (1,25-(OH)2D), 24,25-dihydroxyvitamin D (24,25-(OH)2 D)] and immunoreactive parathyroid hormone (iPTH) were measured in 14 morbid obese patients, who later on were subjected to jejunoileal bypass surgery. The preoperative median values of 25-OHD and 24,25-(OH)2D were reduced compared with controls (P less than 0.001), whereas elevated concentrations were found of 1,25-(OH)2D (P less than 0.005). Median levels of iPTH in the obese group were significantly higher than those found in normal subjects (P less than 0.001). A decrease was observed in serum concentrations of all three vitamin D metabolites following jejunoileal bypass (P less than 0.005). An increase in the serum levels of iPTH and alkaline phosphatase was seen postoperatively (P less than 0.002), probably indicating a secondary hyperparathyroidism. The results show that the vitamin D metabolism is slightly abnormal in severely obese patients. Jejunoileal bypass is followed by severe disturbances of vitamin D metabolism.

24,25-Dihydroxyvitamin D 3↗

Effect of reduced vitamin K esters on vitamin K-dependent carboxylation.

The hypothesis of a vitamin K hydroquinone hemicarbonate as intermediate of vitamin K-dependent carboxylation of glutamic residues, has been examined, by testing several vitamin K hydroquinone esters as inhibitors of the reaction. Among the esters that have been synthetized, a monoacetate proved to be an inhibitor. Kinetic analysis shows that the inhibition is no competitive with respect to vitamin K.

Animals↗

Induction of lesions of selenium-vitamin E deficiency in ducklings fed silver, copper, cobalt, tellurium, cadmium, or zinc: protection by selenium or vitamin E supplements.

In 3 experiments, 684 newly hatched White Pekin ducklings were fed (for 15 to 28 days) a commercial starter mash that was adequate in selenium and vitamin E (Se-E) content, either alone or with supplements of Ag (3,000 mg/kg of feed, as acetate), Cu (1,500 mg/kg, as sulfate), Co (200 or 500 mg/kg, as chloride), Te (500 mg/kg, as tetrachloride), Cd (100 or 500 mg/kg, as sulfate), Zn (3,000 or 6,000 mg/kg, as sulfate), or V (100 mg/kg, as vanadate). The ducklings fed Ag, Cu, Co, Te, Cd, and Zn frequently developed lesions characteristic of Se-E deficiency, such as necrosis of skeletal and cardiac muscle and of smooth muscle of the gizzard and intestine. Complete protection from the muscle lesions produced by Cu, Co, Te, Cd, and Zn supplements was provided by vitamin E (200 IU of alpha-tocopherol acetate/kg) and Se (2 mg/kg, as selenite). Ducklings fed Ag were protected by supplements of vitamin E and partial protection was achieved by Se addition. The birds fed excessive Zn developed pancreatic necrosis and fibrosis that was not prevented by supplements of Se or vitamin E. Terminally, blood glutathione peroxidase activity was low and hepatic Se concentration was increased in the ducklings fed Ag. However, neither blood glutathione peroxidase activity nor hepatic Se concentrations was consistently abnormal in ducklings fed other trace elements, although lesions of Se-E deficiency were often present in these animals.

Animals↗

[Recent discoveries on the biochemical significance of vitamin K and some characteristics of vitamin K dependent proteins].

Vitamin K1 and K2 as well as menadione are in the cells for the largest part transformed into 2-methyl-3-geranylgeranylnaphthoquinone which is hydrated to hydroquinone and which is a constituent of the carboxylase system. By means of this enzyme system in the precursors of the coagulation factors II, VII, IX, and X the proportions of carboxyglutamate are changed into proportions of gamma-carboxyglutamate. Through these proportions of gamma-carboxyglutamate these coagulation factors may be enriched at phospholipid membranes with participation of Ca-ions in the area of injuries of vessels, by means of which the blood coagulation is locally much furthered. By dicoumarol and warfarin this carboxylation is much inhibited and at the same time the degradation of the K-vitamins is much stimulated, the vitamin K content in the liver decreases. The vitamin K depending carboxylase system occurs also in the rough endoplasmatic reticulum of lung, nerve, bone and kidney cells. In the bone cells its participates in the formation of the gamma-carboxyglutamate containing osteocalcin which is of importance for the mineralisation of the bones. Proteins containing gamma-carboxyglutamate were proved also in ribosomes.

1-Carboxyglutamic Acid↗

[Effect of vitamin B1 and vitamin E on methionine poisoning in broiler chickens].

An experiment was carried out with 100 broiler birds of the Leghorn breed, aged 20 days. The birds were divided into groups and were given various amounts of methionine--0,5, 2, and 3 per cent with the basic standard mixture. The clinical signs of methionine intoxication were followed up--drowsiness, weakness in the legs, opisthotonus, and twisting of the neck (torticollis) alons with the loss of equilibrium. It was found that with birds receiving 0.5 per cent methionine with the diet the amount of vitamins A, E, and B1 in the blood serum and the liver rose considerably, while with birds given 2 and 3 per cent methionine with the feed the amount of these vitamins dropped essentially. Therepeutic treatment with 3 mg of vitamin E and vitamin B1 each in the course of 4 to 6 days yielded a good effect. An improvement of the general condition and disappearance of the most typical symptoms of methionine intoxication were recorded.

Animal Feed↗

[Serum levels of vitamin A (retinol), vitamin E (alpha-tocopherol), cholesterol and triglycerides in women with breast cancer. The relationship to some food habits].

The serum levels of vitamin A (retinol), vitamin E (alpha-tocopherol), cholesterol and triglycerides were studied in a group of 40 women who had been diagnosed as having breast cancer, and they were compared to the levels found in a group of 30 healthy women. Our results indicate that the only statistically significant differences found were those involving retinol, with the cancer group showing significantly lower levels (p < 0.05). These parameters have been examined in the context of the frequency of consumption of foods rich in these vitamins and lipids. A higher frequency of consumption of foods rich in the studied vitamins does not appear to cause significant differences in their blood levels. The differences in specific dietary habits have also been analyzed, with both groups showing a high percentage of people who consume skimmed milk and a majority who use olive oil. Nevertheless, the consumption of fruits and vegetables is lower in the cancer group than in the control group.

Adult↗

[Vitamin A, the "anti-infective" vitamin? (author's transl)].

Severe vitamin A deficiency undoubtedly leads to increased susceptibility to infection. On the one hand this is due to the mucosae being damaged by the vitamin deficiency to the extent that these natural barriers are more easily overcome by pathogens. On the other hand, however, also the general defensive condition is weakened, which is partly attributable to a decrease in lymphatic tissue. An increased supply of vitamin A may possibly intensify the production of antibodies, but a definitely positive effect on the course of infections is not established. Therefore, the characterization of vitamin A as "anti-infective" is justified to some extent only.

Animals↗

Biochemical effects of calcium and vitamin D supplementation in elderly, institutionalized, vitamin D-deficient patients.

Forty-five subjects (41 women and 4 men) in long-stay and medium-stay facilities, aged 74 to 95 years (mean 86.4 years), with 25-hydroxy-vitamin D levels less than 12 ng/ml, were treated for six consecutive months with two tablets per day of a preparation containing vitamin D3 (800 IU/day) and calcium carbonate (1 g elemental calcium/day). Serum levels of 25-hydroxy-vitamin D were very low at baseline (5.6 +/- 0.4 ng/ml) and rose significantly under treatment, to normal values, 33.2 +/- 1.2 and 40.9 +/- 2.1 ng/ml after three and six months, respectively (p < 0.001 for both comparisons). Serum calcium increased significantly, by 4.5% (p < 0.001) during the first three months, and remained at a plateau thereafter. Corrected serum calcium rose by 8.9% (p < 0.001) during the trial. No patient developed hypercalcemia. Serum parathyroid hormone levels, which were elevated at baseline (71.6 +/- 5.8 pg/ml; normal, 12 to 54 pg/ml), decreased gradually and significantly throughout the treatment period, by 43.0% and 67.1% after three and six months, respectively (p < 0.001 for both comparisons). Serum alkaline phosphatase activity fell concomitantly, by 9.9% after three months (p < 0.01) and 36.5% after six months (p < 0.001). In conclusion, the preparation used in our study is effective in correcting both the vitamin D deficiency that is prevalent in elderly institutionalized patients and the resultant increase in bone turnover.

Administration, Oral↗

Vitamin K status of healthy Japanese women: age-related vitamin K requirement for gamma-carboxylation of osteocalcin.

BACKGROUND: Vitamin K deficiency is associated with low bone mineral density and increased risk of bone fracture. Phylloquinone (K1) and menaquinone 4 (MK-4) and 7 (MK-7) are generally observed in human plasma; however, data are limited on their circulating concentrations and their associations with bone metabolism or with gamma-carboxylation of the osteocalcin molecule. OBJECTIVES: The objectives were to measure the circulating concentrations of K1, MK-4, and MK-7 in women and to ascertain whether each form of vitamin K is significantly associated with bone metabolism. DESIGN: Plasma concentrations of K1, MK-4, MK-7, undercarboxylated osteocalcin (ucOC; measured by using the new electrochemiluminescence immunoassay), intact osteocalcin (iOC), calcium, and phosphorus; bone-derived alkaline phosphatase activity; and concentrations of urinary creatinine, N-terminal telopeptide, and deoxypyridinoline were measured in healthy women (n = 396). RESULTS: On average, MK-7 and MK-4 were the highest and lowest, respectively, of the 3 vitamers in all age groups. K1 and MK-7 correlated inversely with ucOC, but associations between nutritional basal concentration of MK-4 and ucOC were not observed. Multiple regression analysis indicated that not only K1 and MK-7 concentrations but also age were independently correlated with ucOC concentration and the ratio of ucOC to iOC. The plasma K1 or MK-7 concentration required to minimize the ucOC concentration was highest in the group aged > or =70 y, and it decreased progressively for each of the younger age groups. CONCLUSIONS: The definite role of ucOC remains unclear. However, if submaximal gamma-carboxylation is related to the prevention of fracture or bone mineral loss, circulating vitamin K concentrations in elderly people should be kept higher than those in young people.

Adult↗

Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos.

Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun bear (Ursus malayanus). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park). The nutritional composition of the diet for each species at each institution met probable dietary requirements. Blood samples were collected from each animal and analyzed for vitamin D metabolites 25(OH)D and 1,25(OH)(2)D, vitamin A (retinol, retinyl stearate, retinyl palmitate), vitamin E (alpha-tocopherol and gamma-tocopherol) and selected carotenoids. Family differences were found for 25(OH)D, retinol, retinyl stearate, retinyl palmitate and gamma-tocopherol. Species differences were found for all detectable measurements. Carotenoids were not detected in any species. The large number of animals contributing to these data, provides a substantial base for comparing the nutritional status of healthy animals and the differences among them.

Animals↗

Comparison of blood levels of vitamin A, beta-carotene and vitamin E in abruptio placentae with normal pregnancy.

Levels of vitamin A, beta-carotene and vitamin E in peripheral venous blood of women in abruptio placentae and in normal pregnancy have been compared. Chemical methods were used for the estimation of these compounds. The results show that levels of all three compounds in abruptio placentae are lower than those found in the normal pregnancy. We have earlier shown that levels of ascorbic acid in these subjects are low while other studies have indicated that levels of folic acid in them are also low. Based on our present and earlier published work it is suggested that abruptio placentae is a condition with multiple vitamin deficiency. Whether this is its cause or effect is however not clear.

Abruptio Placentae↗

Establishment of primary cultures from human colonic tissue during tumor progression: vitamin-D responses and vitamin-D-receptor expression.

Primary cultures derived from pre-cancerous and cancerous human colon tissue are essential for understanding normal and abnormal growth function in the large intestine. Here presented are (i) the methodology for routine establishment of primary cultures of normal, adenoma- and carcinoma-derived cells, and (ii) data for the apparently protective role of vitamin-D compounds in colon carcinogenesis. The steroid hormone 1,25-dihydroxyvitamin D3 and some non-hypercalcemic analogs reduce the high mitotic rate of adenoma cells to that of normal colonocytes. After vitamin-D treatment, tumor cells are less proliferative and differentiation is enhanced. Primary-colon-cancer cultures display a mosaic pattern of vitamin-D-receptor expression, at the mRNA level and at the protein level, with varying intensity of expression in positive cells. This suggests that, in human colorectal tumors in vivo, a large fraction of cells will respond to genomic action of vitamin-D compounds.

Antineoplastic Agents↗

Effect of simultaneous administration of vitamin C, L-cysteine and vitamin E on the melanogenesis.

The effect of simultaneous administration of vitamin C (ascorbic acid), L-cystein (Cys) and vitamin E (tocopherol) on the melanogenesis in vivo and in vitro was studied. Forty-eight brownish guinea pigs were divided into 4 groups as follows: VC group, VC+Cys group, VC+Cys+VE group and control group. They were given these vitamins by oral administration every day. UV-B exposure (0.384 J/cm2) on their depleted back skin was done at the day 8, 10, 12, 15 17 and 19. After UV-B irradiation, vitamins were administrated further 3 weeks. The luminosity score was measured using a Color Reader CR-11 (Minolta, Co) and the numbers of DOPA-positive melanocytes of their back skin were counted. B16 melanoma cells were incubated with VC, N-acetyl cystein (NAC) and VE. After 4 days of incubation, cells were harvested. The melanin contents and the tyrosinase activities in cells were measured. The luminosity score in the VC+VE+Cys group was higher than those in the other groups. The numbers of DOPA-positive melanocytes of guinea pigs treated with VC, VE and Cys were significantly decreased compared with those in VC group. In B16 melanoma cells, simultaneous treatment of VC, VE and NAC was the most effective to decrease the melanin contents and to inhibit tyrosinase activity.

Animals↗

Aluminum intoxication in vitamin D-deficient rats: studies of bone aluminum localization and histomorphometry before and after vitamin D repletion.

Aluminum accumulation by both dialysis patients and nonuremic patients, requiring chronic total parenteral nutrition, may be an etiological factor in the development of severe osteomalacia. To study the role of aluminum toxicity in bone, further experiments have been conducted in the nonuremic, vitamin D-deficient rat. Weanling rats were raised on vitamin D-deficient diets, and half received parenteral aluminum (5 mg/wk), for 30 days. In the first experiment low doses of 25-OH cholecalciferol (500 ng/week) were given subcutaneously for a further 30 days. Control rats were maintained on a similar protocol, but were supplemented with cholecalciferol (5 micrograms/week) from the outset until sacrifice at 60 days. In the second experiment a single bolus of cholecalciferol (5 micrograms) was given to study short-term changes in serum biochemistry and bone histology at 96 hr. Quantitative bone histomorphometric analyses of the proximal tibial metaphysis were made in all experimental groups. In the experimental vitamin D-deficient group, with the highest bone aluminum content (as assessed by extraction of whole bone aluminum), X-ray microanalysis was performed to determine the distribution of aluminum in bone tissue and bone cell organelles. The results showed that control rats treated with prolonged aluminum therapy (30 mg over 60 days) had evidence of both reduced osteoid matrix synthesis and mineralization. However, in vitamin D-deficient rats, there was no evidence that aluminum exacerbated the osteomalacic lesion, even though there was histochemical evidence of aluminum deposition at the bone-osteoid interface.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum↗

Determination of potential content of vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) in gelatin-coated beadlets, oil-based mixtures, and multivitamin tablet and capsule formulations.

A high-performance liquid chromatographic procedure was used to determine routinely the potential vitamin D content in raw materials and multivitamin formulations. The method employs a microparticulate silica column to separate vitamin D from its degradation products as well as other fat-soluble vitamins. Sample preparation is simple, and the chromatographic time is less than 20 min when progesterone is added to the injection mixture as an internal standard. Replicate analyses of complex multivitamin formulations demonstrate precision with a relative standard deviation of less than 4%. Spiked placebos typically show 98--100% recovery and a linear chromatographic response. The use of bulk drug as a working reference standard is recommended for the determination of the potential vitamin D concentration in pharmaceutical multivitamin preparations.

Capsules↗