Acta vitaminologica et enzymologica最新文献

Weanling rats have been fed different diets containing hydrogenated coconut oil or a mixture of grapestone + linseed oil as dietary fats. Groups of 12 animals have been sacrificed at weanling or after 60 or 120 days of this dietary treatment. Body and brain weight, brain total lipids, phospholipids, cholesterol, cerebroside, fatty acid content and fatty acid composition have been evaluated. The diet rich in alphalinolenic acid (C 18:3 n-3) induced a significant increase of the n-3 polyunsaturated fatty acids (C 22:5 and C 22:6, n-3) in the brain, with respect to the other experimental conditions.

The problem of transmethylations, the genesis of the labile methyl groups, the chemical structure of a transmethylating active substance are briefly explained and discussed. A methodology to characterize quickly the substances donor and acceptor of methyl groups is here described: it utilizes the ox crystalline lens in the presence of nicotinamide. The methodology is based on the irreversible system nicotinamide-trigonellinamide, by means of the vitamin B1 as catalyst.

The antineoplastic effects of a novel retinoid derivative E5166 on cultured human neuroblastoma, GOTO cells, were investigated. E5166, as well as retinoic acid and retinol, suppressed the proliferation of GOTO cells and the synthesis of DNA, RNA and protein; the inhibitory potency of E5166 was not stronger than that of the natural vitamin A derivatives. E5166 also inhibited amino acid transport, but was found to stimulate sugar transport in the neuroblastoma cells.

The effect of 1-alpha-OHD3 on the rate of decline of renal function was studied in 18 patients with predialytic chronic renal failure. 9 patients with serum creatinine 4.19 +/- 1.63 mg/dl, were treated with 1-alpha-OHD3 0.4 +/- 0.11 micrograms/day and a low phosphate diet and 9 patients, with serum creatinine 3.69 +/- 1.24 mg/dl, received the low phosphate diet alone. In the first group retrospectively in 8 patients up to 3-44 months and prospectively in all patients reciprocal values of serum creatinine levels fell linearly with time. Comparison of the slopes of the regression lines before and following the start of treatment did not show statistical differences in 6 cases, in 1 case the decline of renal function improved significantly and in 1 case it became positive. Serum calcium increased significantly (p less than 0.025), alkaline phosphatase decreased (p less than 0.005) and serum iPTH decreased in 6 of 8 cases. In the low phosphate diet group, serum calcium, alkaline phosphatase did not change while iPTH increased in 8 of 9 cases. The rate of decline of renal function before treatment in 3 cases did not improve after the institution of the diet. In conclusion improvement or prevention of secondary hyperparathyroidism in predialytic chronic renal failure can be achieved with daily doses of less than or equal to 0.5 micrograms 1-alpha OHD and a low phosphate diet. The small increment in serum calcium levels induced by the treatment did not accelerate the deterioration of renal function while showing a better control of alkaline phosphatase and serum iPTH than the low phosphate diet alone.

Intestinal absorption of vitamin A was determined in a group of rats rendered uremic by subtotal nephrectomy. The results were compared with those obtained in a group of sham-operated control animals. Absorption studies were performed by in-vivo perfusion of an isolated loop of the proximal jejunum with intact blood and lymphatic supply. The rate of intestinal absorption of vitamin A, in the uremic groups was nearly identical to that found in the control group. It thus appears that intestinal absorption of vitamin A is not affected by experimental uremia in the rat.

Weanling female rats randomly divided into three groups were fed a basal alipidic diet added with 10% (w/w) corn oil, soybean oil or linseed oil. After thirty and ninety days of dietary treatment the rats were killed and the fatty acid composition of brain, optic nerve and visual cortex was determined. The results demonstrate a different sensitivity to the diet of the different structures examined and, for the linseed oil treated rats, a strong decrease in the proportions of the total (n-6 + n-3) polyunsaturated fatty acids in all the structures examined.

Forty patients suffering of different forms of acne (papulo-pustular, nodulo-cystic, conglobata, rosacea), all in severe conditions and non-responding to other treatments, have been administered 13-cis-retinoic acid p.o. The treatment resulted in a complete and ultimate healing in 31 pts (77.5%) and a marked amelioration in the remaining 9 cases. The initial drug dosage was 40 mg/die (an average of 0.66 mg/kg/die) but it was reduced along the treatment to 2.5 mg/die, a still effective dose. The average treatment duration was 24 weeks (range: 12 to 40). The tolerance was generally excellent, but some adverse effect have been recorded, mainly localized in the skin and mucosa. Increases of total serum cholesterol (66% of the cases) and of triglyceride (72%) level have been observed. This effect was reversible at the end of the treatment. As a conclusion we can confirm that the 13-cis-retinoic acid is the most effective drug for the pharmacotherapy of severe acne.

The incidence of malnutrition and the effect of hospitalization was evaluated in 100 consecutive admissions to the Clinical Pathology R Department of the University of Genoa. Nutritional deficiencies were evaluated at the time of admission and discharge from the Hospital, among patients hospitalized 2 weeks or longer, using the following nutrition-related parameters: body fat, muscle proteins, weigh, rate of weight loss plasma proteins level, vitamin B12 and folic acid plasma level, plasma iron and ferritin. We also considered the nutritional alterations in malnourished patients with relation to appetite decrease and to pathological status. At the admission to the hospital, the findings showed a high incidence (79%) of alterations in some nutritional parameters. In patients with nutritional impairments we observed a worsening of most of the nutritional parameters during hospitalization, especially in patients with severe appetite decrease and those affected by sepsis, neoplastic, gastric and renal diseases.

Acid -soluble nucleotides from the mycelia were clearly separated by column chromatography on Dowex 1 X 2(HCOO-, 200 to 400 mesh). Under the experimental conditions used [2--14C] xanthine and [2--14C] guanine added were not incorporated into adenosine nucleotides but only into the guanosine nucleotides-GMP, GDP, GDP-Man, and GpA. Purines labeled at carbon 2 were effectively transferred to riboflavin but not radioactivity from [8--14C]--hypoxanthine was detected in the produced riboflavin. Comparison of the specific activity/time curves of guanosine nucleotides and riboflavin indicated that the specific activity of newly formed riboflavin coincides perfectly with that of GTP during incubation, and that the specific activity of accumulated riboflavin, at its maximum value, intersects the GTP curve. Thus, the kinetic studies with whole cells of E. ashbyii provide clear evidence that, among various nucleotides, GTP is the immediate precursor of riboflavin, and further attest that the intermediates involved in the biosynthetic pathway of the nucleotide precursor to riboflavin are in a trace amounts but have high turnover rates and, that the biosynthetic pathway has no salvage pathway for the intermediate derivatives, di- and tri-amino pyrimidines.