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Serum vitamin B12, serum and red cell folates, vitamin B12 and folic acid binding proteins in women taking oral contraceptives.

Serum and red cell folate, FABP, serum vitamin B12 and vitamin B12 binding proteins were determined in 20 women taking oral contraceptives continuously for at least one year. Studies were also performed on 50 apparently healthy women with history of never taken or not taking oral contraceptives for at least one year as a control group. Serum vitamin B12 level, UBBC and TBBC in women taking oral contraceptives were slightly but not significantly lower than those of the control group. TCI and TCIII increased with a decreased TCII, so that UBBC was within the normal limit. Serum folate was non-significantly lower while red cell folate was significantly lower in the oral contraceptive group than those of the control group. However, all cases of the former showed red cell folate over 200 ng/ml. A highly significant increased serum FABP was demonstrated in the women taking oral contraceptives. This was probably due to the increased synthesis of the FABP in order to bind more folate from the low serum folate and the hormonally induced stimulation.

Adult↗

Serum vitamin B12 and folate levels, vitamin B12 and folic acid binding proteins in patients with primary carcinoma of the liver.

Serum vitamin B12, folic acid, vitamin B12 and folic acid binding protein concentration were determined in 31 patients with primary carcinoma of the liver. Serum vitamin B12 level was found to be higher in 16 of 31 (52%) patients with carcinoma of the liver and the mean value was also significantly higher than that of the control group. There was no significant difference between the mean values of serum UBBC of these 2 groups. TCI and TCIII increased while TCII decreased considerably in the patient group. Serum folate level in patients with primary carcinoma of the liver was significantly lower than that of the control group. About 39% of these patients had serum folate level lower than the lowest value of the control group. Serum FABP in the former group was also significantly higher than that of the latter group.

Adult↗

[Vitamin B12, an analgesic vitamin? Critical examination of the literature].

Since 1950 it would seem that in some countries vitamin B12 has been regarded as a painkilling vitamin. Only one of the 94 published clinical trials fails to point to this conclusion, but none of these trials meets current methodological requirements for investigation of an analgesic. The hypothesis that vitamin B12 possesses painkilling properties must therefore be questioned, especially as no anti-nociceptive effect is reported in animal experiments.

Analgesics↗

Vitamin D metabolites in renal insufficiency and other vitamin D disorders of children.

Serum vitamin D metabolites were measured in relation to factors responsible for the synthesis of 1,25(OH)2D in children with renal disease and other disorders of vitamin D metabolism. Severe renal failure (CCr less than 15 ml/min/1.73 m2) was associated with a reduction in 1,25(OH)2D to 25% of mean normal levels, a very high PTH/1,25(OH)2D ratio of 75 (normal = 0.74), and a 60% reduction of serum 24,25(OH)2D. At CCr values between 15 and 50 ml/min 1.73 m2, 1,25(OH)2D was 50% of normal, despite a PTH/1,25(OH)2D ratio of 7 and a normal 24,25(OH)2D value. Above clearance values of 75 ml/min/1.73 m2, 1,25(OH)2D and the ratio were normal. Oral 1,25(OH)2D therapy in severe chronic renal insufficiency caused a fall in this ratio from 75 to 8. High PTH/1,25(OH)2D ratios were found in hypophosphatemic rickets and vitamin D-deficiency rickets, indicating reduced synthesis of 1,25(OH)2D relative to PTH. Low ratios were found in hypoparathyroidism and sarcoidosis, possibly indicating independence of PTH stimulation in 1,25(OH)2D production. The ratios of calcium/1,25(OH)2D and phosphate/1,25(OH)2D also provided useful information in each of these conditions, indicating that the use of such series of ratios in selected patients may promote a better understanding of pathogenic mechanisms and of the response to therapy.

Adolescent↗

Analysis of fat-soluble vitamins. XXV. High performance liquid chromatographic determination of vitamin D in multivitamin preparations: collaborative study.

The HPLC method for determining vitamin D in multivitamin preparations was studied collaboratively. Samples were distributed to 43 laboratories in 10 countries. Twenty-four laboratories gave their results. The method specifies a reverse phase system for the cleanup and a straight phase system for the determination. Difficulties arise when laboratories are equipped with HPLC apparatus with a single column. Laboratories experienced in vitamin D analysis reported good results, even if they were equipped with a single column HPLC apparatus. Eleven of the 24 laboratories reported satisfactory results. For this rather complicated method, the coefficient of variation for a single assay is acceptable. The method has been adopted official first action as an alternative procedure to the chemical method for determining vitamin D in multivitamins.

Chromatography, High Pressure Liquid↗

Effect of vitamin E, vitamin C and beta-carotene on LDL oxidation and atherosclerosis.

OBJECTIVE: The oxidative modification of low density lipoprotein (LDL) may be an early step in atherogenesis. Furthermore, evidence of oxidized LDL has been found in vivo. The most persuasive evidence shows that supplementation of some animal models with antioxidants slows atherosclerosis. The purpose of this review is to examine the roles that vitamin E, vitamin C and beta-carotene may play in reducing LDL oxidation. DATA SOURCES: English language articles published since 1980, particularly from groups active in this field of research. STUDY SELECTION: In vitro, animal, and human studies on antioxidants, LDL oxidation, and atherosclerosis were selected. DATA SYNTHESIS: Vitamin E has shown the most consistent effects with regard to LDL oxidation. Beta-carotene appears to have only a mild or no effect on oxidizability. Ascorbate, although it is not lipophilic, can also reduce LDL oxidative susceptibility. CONCLUSIONS: LDL oxidizability can be reduced by antioxidant nutrients. However, more research is needed to establish their utility in the prevention of coronary artery disease.

Animals↗

Concentration of vitamin A, retinol-binding protein and prealbumin in serum in response to stress: A contribution to the prevention of stress ulcers by means of vitamin A.

Starting from clinical observations indicating a reduction in the stress ulcer rate by parenteral administration of high doses of vitamin A after burns, traumatic damage and surgical operations, the pattern of vitamin A, retinol-binding protein (RBP) and prealbumin (PA) concentrations in serum was studied in a number of patients with multiple traumas (group 1; n equals 32), cranial-cerebral lesions and postoperative conditions (group 2; n equals 27) and patients having undergone gynecologic operation (group 3; n equals 15); the results obtained were compared with the concentrations determined preoperatively and the normal values as reported in the literature. It was seen that the concentrations in the 3 groups were significantly reduced for all 3 parameters. This fall in concentration was observed not only when food was withheld but also with optimal supplies of essential nutrients. Intestinal hemmorrhages occurred in altogether 6 patients of groups 1 and 2 who exhibited serum vitamin A concentrations in the extremely low range and in the lower normal range.

Adolescent↗

Modificatory effect of vitamin C and vitamin B-complex on meiotic inhibition induced by organophosphorus pesticide in mice Mus musculus.

Administration of organophosphorous pesticide Malathion and Rogor (both @ 0.2 micrograms/kg body wt/day) upto ten days was found to decrease the division rate in the primary spermatocytes of mice. The concurrent administration of vitamin B-complex (0.3 ml of 1% polybion) or ascorbic acid (0.25 ml of 1% Redoxon) with the pesticide could nullify the meiotic inhibition caused by the pesticides. The vitamins were not found to produce any significant effect on the division rate. Possible mechanism(s) behind this vitamin mediated nullification of meiotic inhibition are discussed.

Animals↗

[Assay of fat-soluble vitamins--vitamin D].

Methods for determination of vitamin D, 25-OH-D, 24,25(OH)2D and 1,25(OH)2D in plasma are reviewed. A method for simultaneous determination of the D2 and D3 compounds of vitamin D and the metabolites in plasma is established. The method includes extraction of lipid, followed by three steps of HPLC for clean-up and separation. Vitamin D and 25-OH-D are quantified by HPLC with a UV detector, while 24,25(OH)2D and 1,25(OH)2D are assayed by CPBA and RRA methods, respectively. The assayed values for concentrations of the compounds in plasma of normal subjects and various kinds of patients are shown. A simplified method for assaying 1,25(OH)2D in plasma using calf thymus receptor is also introduced.

Chromatography, High Pressure Liquid↗

Mechanism of action of anticoagulants: correlation between the inhibition of prothrombin synthesis and the regeneration of vitamin K1 from vitamin K1 epoxide.

It has been proposed that coumarin and indandione anticoagulants inhibit clotting protein synthesis by preventing the regeneration of vitamin K1 from its 2,3-epoxide metabolic. To test this hypothesis, the effects of nine coumarin and indandiones on prothrombin synthesis and the conversion of vitamin K1 epoxide to vitamin K1 were measured. There was a good correlation between the inhibition of prothrombin synthesis and the epoxide-K1 conversion both in vivo and in vitro. Diphenadione (2-diphenyl acetyl-1,3-indandione) caused a delayed inhibition of prothrombin synthesis which correlated with a delayed inhibition of the epoxide-K1 conversion in vivo. These results provide strong evidence for the proposed mechanism of action of coumarin and indandione anticoagulants.

Animals↗

Potential interventions for the prevention of childhood pneumonia in developing countries: a meta-analysis of data from field trials to assess the impact of vitamin A supplementation on pneumonia morbidity and mortality. The Vitamin A and Pneumonia Working Group.

Reported are the results of a meta-analysis (12 large-scale field trials in seven countries) of the impact of vitamin A supplementation on pneumonia morbidity and mortality, undertaken as part of a wider review process of a range of possible potential interventions for the prevention of childhood pneumonia. The summary estimate of the relative risk for the impact of vitamin A supplementation on pneumonia incidence was 0.95 (95% confidence interval (CI) = 0.89, 1.01), and for pneumonia mortality, 0.98 (95% CI = 0.75, 1.28). This is in marked contrast to the substantial impact of vitamin A supplementation on all-cause mortality (combined rate ratio (RR) = 0.77, 95% CI = 0.71, 0.84), and on diarrhoea-specific and measles-specific mortality. There was no evidence for a differential impact on pneumonia mortality by age. Since the majority of pneumonia deaths occur in the first year of life, we complemented the paucity of data on pneumonia-specific mortality among this age group with a detailed examination of all-cause mortality among infants. The mortality reduction in the 6-11 month age group was consistent with that observed for older age groups (RR = 0.69; 95% CI = 0.54, 0.90), but there was no reduction for 0-5 month-olds (RR = 0.97; 95% CI = 0.73, 1.29).

Age Distribution↗

Three synthetic vitamin D analogues induce prostate-specific acid phosphatase and prostate-specific antigen while inhibiting the growth of human prostate cancer cells in a vitamin D receptor-dependent fashion.

Numerous studies have indicated that the secosteroid hormone 1alpha, 25-dihydroxyvitamin D3 protects against the development of clinical prostate cancer (PC). Whether this hormone also has therapeutic potential for patients with advanced PC has not yet been evaluated. Several synthetic vitamin D analogues are now available that have reduced hypercalcemic effects and yet effectively induce differentiation in some cell types. For these reasons, these analogues may be safer and more effective for cancer therapy than the natural hormone. In the current study, 13 such analogues were screened for their abilities to inhibit the growth of PC cell lines. Three of the most consistently effective analogues (Ro 23-7553, Ro 24-5531, and Ro 25-6760) were then chosen for further analysis. Growth studies using clones of the JCA-1 cell line that were transfected with the vitamin D receptor cDNA indicate that the antiproliferative effects of these analogues require vitamin D receptor expression. Furthermore, these three analogues induce the secretion of prostate-specific acid phosphatase and prostate-specific antigen (two markers of the differentiated prostatic phenotype) in the cell line LNCaP. These in vitro studies suggest that Ro 23-7553, Ro 24-5531, and Ro 25-6760 should be further evaluated as therapeutic agents for the treatment of PC.

Acid Phosphatase↗

Change in tissue concentrations of lipid hydroperoxides, vitamin C and vitamin E in rats with streptozotocin-induced diabetes.

The tissue concentration of lipid hydroperoxides, which was determined by a specific method involving chemical derivatization and HPLC, increased significantly in the heart, liver, kidney and muscle of diabetic rats 8 weeks after the intraperitoneal injection of streptozotocin compared with that of the control group. These results demonstrate that an enhanced oxidative stress is caused in these tissues by diabetes. Vitamin C concentrations of the brain, heart, lung, liver, kidney and plasma of the diabetic rats decreased significantly after 8 weeks compared with those of the control group. Vitamin E concentrations of the brain, heart, liver, kidney, muscle and plasma of the diabetic rats increased significantly after 4 weeks compared with the control group. After 8 weeks, an elevation in vitamin E concentration was observed in the heart, liver, muscle and plasma of the diabetic rats.

Analysis of Variance↗

Intestinal absorption of vitamin B12 in patients with chronic pancreatic insufficiency and the effect of human duodenal juice on the intestinal uptake of vitamin B12.

The mean absorption of vitamin B12 (Schilling test) was 13.1 +/- 1.0 (% +/- S.E.M.) in 21 patients with chronic pancreatic insufficiency and 17.6 +/- 1.4 in 13 control patients (p less than 0.01). There was no correlation between pancreatic bicarbonate production after secretion stimulation and vitamin B12 absorption in the patient group (r = 0.117). Human duodenal juice reduced the uptake of 57CoB12-rat intrinsic factor (IF) by perfused rat small intestinal segments in vivo (p less than 0.01) as well as the uptake of 57CoB12-human IF by purified guinea-pig intestinal brush borders in vitro (p less than 0.01). The results confirm reduced absorption of vitamin B12 in chronic pancreatic insufficiency, but the mechanism remains uncertain.

Adolescent↗

Serum vitamin A and vitamin E in Japanese black fattening cattle in Miyazaki prefecture as determined by automatic column-switching high performance liquid chromatography.

Japanese Black fattening cattle in Miyazaki prefecture, Japan were examined for serum vitamin A (V. A) and vitamin E (V. E) by automatic column-switching high performance liquid chromatography with automated deproteinization. Results indicated that most Japanese Black fattening cattle in Miyazaki prefecture may be provided with V. A supplement and diets including little V. E, moderate beta-carotene and V. A during the early fattening stage, and diets including little beta-carotene, V. A and V. E during the middle and later fattening stages. Therefore, monitoring serum V. A and V. E in Japanese Black fattening cattle throughout the fattening period seems necessary for farmers in Miyazaki prefecture to avoid economic loss attributable to these deficiencies.

Aging↗

Effects of a vitamin pool (vitamins A, E, and C) on the tissue necrosis process: experimental study on rats.

During surgical procedures on the epidermis, either aesthetic or reconstructive, the medical literature shows that certain technical standards and skin flap proportions should be followed, unless the risk of necrosis increases, in different degrees, directly related to the trauma. This study evaluates the evolution of skin flaps on the dorsum of rats treated with a vitamin pool (VP) (vitamins A, E, and C). Twenty-six rats, divided into two groups, were used: (A) the treated group (13 specimens), in which we performed a dorsal skin flap and applied the VP, and (B) the control group (13 specimens), in which we performed a flap on the dorsum without application of the VP. Our results demonstrate that, at the macroscopic level, the group treated with the VP had more tissue sufferance, whereas at the microscopic level, small statistical differences were observed between the groups and also between the vertex and the middle of the flap. Despite these small differences, better results were obtained in group A, showing that in this study the clinical aspect did not correspond to the histological features.

Animals↗

Vitamins and arthritis. The roles of vitamins A, C, D, and E.

There are at least four mechanisms whereby the nutrient vitamins A, C, D, and E may be related to the processes that impede or give rise to OA. These nutrient vitamins have major roles in modulating oxidative stress, participating in immune responses, and contributing to cell differentiation. There is a substantial need to understand the contribution of these nutrients to OA, because they may provide important insight into ameliorating the initiation and progression of the disease. Simultaneously, greater understanding will add rationality to an area of potential intervention that is often based on anecdote. Investigation will be complex; there is the need to select appropriate systems. Typical animal model systems used in the study of OA are inappropriate because most animals can synthesize ascorbic acid. There is the need to disaggregate, as much as possible, the numerous subsets of OA and the plethora of processes that contribute to that heterogeneity. Certainly, there is the need to recognize the interdependency of the actions of each of these nutrients at the cellular level. Furthermore, humans rarely consume these nutrients as independent products. For example, watermelon is a primary source of both ascorbic acid and beta-carotene. Failure to address these complexities denies the scientist the opportunity to advance our understanding of health and disease processes. More importantly, failure to address these complexities denies the person with OA the opportunity to address his or her own health.

Animals↗

Changes in bone metabolism and epiphysial growth plate in bovine Hyena disease induced by administration of vitamin AD3E premix or Vitamin A.

The changes in bone metabolism and morphology of chondrocytes in bovine Hyena disease caused by administration of vitamin AD3E premix (V-AD3E) or vitamin A (V-A) were examined. At the each age, 5 calves were used. Among them, Hyena disease was recognized in 3 calves; a calf administered a high dose of V-AD3E premix (V-A 3,000,000, V-D3 300,000, and V-E 1,200 I.U./day), a calf administered a half dose of the V-AD3E premix, and a calf administered only V-A 3,000,000 I.U./day. The remaining calves without Hyena disease were a calf administered only V-D3 300,000 I.U./day and a control calf. Each agent was administered orally for 10 days from 1 week after birth. In the 3 calves with Hyena disease, the bone metabolism in bone histomorphometry of ilium was in the state of low turnover at the age of 50 days. The bone volume was small at the age of 12 months. The epiphysial growth plates of the distal femurs and the proximal tibias partially disappeared and the chondrocyte lacunas in them were flattened. The matrix fibers of epiphysial growth plates were thinner in diameter and higher in density than those of the control calf. In the calf administered only V-D3, the values of bone volume decreased with aging. In conclusion, Hyena disease may be caused by excessive administration of V-A, because hypervitaminosis A suppressed the activity of differentiation and proliferation in chondrocytes and osteoblasts, and excessive administration of V-D3 may promote these actions.

Animals↗