1000 resultados para vitamina A
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As farinhas infantis, alimentos que se destinam a recém-nascidos e crianças até à idade pré-escolar, devem satisfazer todas as necessidades nutricionais que se verificam durante o período de crescimento e desenvolvimentos físico e mental desta faixa etária. Desta forma, são frequentemente adicionadas prémisturas de vitaminas e minerais durante a sua produção (fortificação), de maneira a que a quantidade adicionada e a composição do produto final sejam concordantes com a legislação comunitária em vigor. A implementação, na linha de produção, de métodos alternativos de análise “amigos do ambiente” e passíveis de obter resultados rápidos acerca da composição nutricional dos produtos alimentares, mesmo antes destes serem embalados, permite reduções de tempo, custos e um melhor controlo do processo de produção. A espectroscopia FT-NIR e a espectroscopia de XRF são técnicas que permitem a quantificação de micronutrientes e possuem características fundamentais ao controlo rápido de processos. Neste trabalho foram desenvolvidos modelos de calibração para quantificação de zinco, por espectroscopia de XRF, em três receitas de pré-misturas de vitaminas e minerais. Construíram-se dois modelos de calibração, um com um R2 de 0,990 e um SEC de 26,624 mg/100g e outro com um R2 de 0,927 e um SEC de 18,838 mg/100g. Estes resultados indicam que os modelos de calibração construídos são adequados e podem ser usados na determinação rápida do teor de zinco em pré-misturas de vitaminas e minerais. Foram também verificadas as rectas de calibração existentes para quantificação de cálcio e ferro por espectroscopia de XRF e quantificação de vitamina C por espectroscopia FT-NIR para aplicação nas novas receitas de pré-misturas de vitaminas e minerais.
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Objective: To conduct a systematic review of the Vitamin “A” food consumption by pregnant women in Brazil. Methods: The review consisted of a search for articles published in the period from 1999 to 2015 in SciELO, PubMed, and LILACS databases. At the end, eight articles were selected for this review. Results: The methods used for the analysis of the intake of vitamin “A” were: food frequency questionnaire (FFQ) – considering the diet or only vitamin “A” foods and the dietary recall (24hDR). Only two articles estimated the adequacy of the Vitamin “A” food consumption by the population assessed. Some methodological limitations were quite frequent, emphasizing the lack and/or limitation of information on the sample representativeness, loss of studies, accuracy of the methods applied and the control of confounding variables. Conclusion: It is observed that there are still few studies that critically assess the Vitamin “A” food consumption by pregnant women in Brazil, and that the identification and control of possible biases of the dietary surveys can improve the reliability of the information found.
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The vitamin A is essential to animals because of its participation in a great number of biological functions. The investigation of this vitamin s concentrations is important to serve as reference to normality parameters. This study had as aim to analyse the serics and hepatics concentrations of vitamin A in two groups of bovines and to compare the hepatics concentrations to the present requeriments of vitamin A for pregnant women. It was also appraised the consume habit of bovine liver by pregnant women through of the alimentary frequency quest. Two groups of bovine were studied and the first was formad by Nelore bovine breed and the second by bovine without defined breed (WDB). It was analysed 120 samples: 60 of liver and 60 of serum. The method used to dose retinol was High Performance Liquid Cromatography (HPLC). The average (+ sd) of retinol concentrations in Nelore breed bovine and WDB liver were 16947,8 + 6866,9 and 5213,1 + 2517,2 µg of retinol/100g and at serum 39,6 + 17,9 e 28,6 + 9,4 µg of retinol/dL, respectively. No statistically significant correlation was found between hepatic and the serum retinol. The bovines in this study had adequate vitamin A levels. Independently of animal breed, the daily ingestion of bovine liver is not advised for pregnant women who show adequate support of vitamin A. The consume of bovine liver by pregnant women consulted on school maternity hospital Januário Cicco, UFRN, Natal RN, was considered high
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The caprine milk is a product of high biological value and high digestibility. Due to these characteristics it is quite used by newly born children that are not breastfed or that are intolerant to the bovine milk. The vitamin deficiency is a public health problem in underdeveloped areas as the Northeast of Brazil and where areas the caprine ones adapt very well. The present study was led to analyze the influence of the feeding in the vitamin levels in the caprine milk. The animals used were the races Saanen and Murciana, divided in three groups. The first group with 38 animals of race Saanen and the second with 30 animals of race Murciana were, fed with concentrated and voluminous. A third group with 20 animals of the race Saanen was fed exclusively with voluminous. The four group was added with 10. 000 UI of retinol palmitato, administered directly, like capsule, in the mouth of animal. Parallel it was verified the level of retinol of milk in the beginning and final of the sucked, in the goats of the second group (race Murciana n =30). The retinol of caprine milk was determined through the system of liquid cromatografia of high efficiency (HPLC). The retinol levels in the studied groups were respectively: first (38. 5 ± 12. 7 μg/100ml), second (40. 5 ± 9. 7 μg/100ml); third, with 20 animals of race Saanen fed exclusively with voluminous (23. 1 ± 6. 7 μg/100ml) and in the group a, suplementation with 10. 000 UI of retinol palmitato (43,7 ± 18,8 μg/100ml) before, and (61,9 ± 26,9 μg/100ml) after the supplementation. It was not found significant difference between the averages from animals of the first and second group, that were fed with the same concentrate diet and voluminous, showing that the retinol levels in the milk of these two races are equivalent. Already in the animals of the first and third group that they were fed with different diets, in those which diet was just voluminous, a drastic reduction was verified in the retinol levels. In relation to the retinol of the milk in different moments from the same sucked, it was observed in the beginning of the breast-feeding (22. 6 ± 9. 8 μg/100ml) and at the end of the sucked (49. 6 ± 14. 7μg/100ml), being the difference between the averages, statistically significant (p < 0,0001). Already in the animals that were supplemented, a significant increase was observed in the retinol concentration, being obtained a medium response of 41,85%
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The intake of adequate quantities of food, including those rich in vitamins, is necessary for a healthy life. The lack of vitamin A has been characterized as a public health problem in developing countries, however, a high intake of vitamin A can result in toxic and teratogenics effects. High concentrations of vitamin A have been observed in the livers of animals. The objective of this study was to assess the levels of retinol in chicken livers and verify the effect of frozen storage on these levels. 64 livers from two chicken strains, Cobb and Ross, were used, came from four different farms. We examined 32 livers from each strain, 8 samples from each farm. Liver sample were homogenized individually, then 4 aliquots were taken from each sample. One of aliquots was analyzed immediately after slaughter (T0), the others were analyzed after 30, 60 and 90 days of storage at -18oC (T30, T60 and T90, respectively). Retinol dosage in the liver was determined by High Performance Liquid Chromatography (HPLC). The levels of retinol varied significantly according to the strain. The mean retinol value in the fresh samples was 6678.0 ± 1337.7 and 8324.1 ± 1158.5 µg/100g in the Cobb and Ross strain, respectively. Values of 4258 ± 918.7 ± 1391.7 and 4650.5 ± 1391.7 μg/100g were found after 90 days of storage for Cobb and Ross strain, respectively. The liver freezing caused a significant reduction in their levels of retinol, causing a loss of up to 44% with respect to fresh livers. The reduction in retinol levels occurred from 30 days of storage. Even with the losses from the frozen, the ingestion of a typical portion of 100 g of liver, regardless the chicken strain analyzed, surpass all recommendations of consumption and the maximum tolerable intake of vitamin A (3000 μg/day) for adults
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Vitamin A deficiency (VAD) is a serious public health problem in developing countries, and as a therapeutic and prophylactic measure retinil palmitate is being supplemented. Nevertheless its efficacy has been questioned. The objective of the study was to evaluate the supplementation of two retinil palmitate megadosis on the serum retinol levels of post partum healthy mothers from Dr. José Pedro Bezerra (Hospital Santa Catarina) hospital, Natal - RN. The enrolled women (n=199) were randomly distributed into three studied groups and supplemented with retinil palmitate immediately after delivery with a single 200,000 IU dose (group S1), two 200,000 IU dose (group S2) with 24h difference between the doses, or no supplementation (group C). Among women selected, 143 remained until the end of the study. The influence of vitamin A dietary intake was evaluated during pregnancy and after 30 days of delivery. The average intake of the population was reasonable, but a high prevalence of inadequate intake was found. Retinol in colostrums and mature milk was determined by high performance liquid chromatography (HPLC). The retinol average in colostrums and mature milk in the supplemented and control groups were adequate according to the reference values. In colostrums, women from groups C, S1 and S2 presented retinol averages by milk volume of 94.8 ± 40.2 µg/dL, 92.2 ± 50.0 µg/dL and 91.8 ± 53.7 µg/dL, respectively. No difference was found between these averages (p=0.965), this was also seen when the values where expressed as µg/g of fat (p=0.905). After 30 days of delivery, retinol per milk volume differed between the control group (36.6 ± 17.5 µg/dL) and groups supplemented with 200,000 IU (51.0 ± 28.8 µg/dL) or 400,000 IU (55.2 ± 31.6 µg/dL) of retinil palmitate (p<0,05). Nevertheless, when S1 and S2 groups where compared, no significant difference was found (p=0.97). Considering retinol/g of fat, the means were 12.7 ± 6.7 µg/g, 15.6 ± 8.3 µg/g and 17.2 ± 8.9 µg/g for groups C, S1 and S2, respectively, with significant difference between groups S2 and C (p=0,01). Subclinical VAD prevalence showed a serious public health problem in the study population (32% in colostrums and 31.5% in mature milk). When analyzing the groups separately, the group which received two doses (200,000 IU + 200,000 IU) presented the lowest VAD prevalence (20.7%). Retinil palmitate supplementations of 200,000 IU and 400,000 IU (divided in two doses) in the immediate post partum showed no significant difference. Nevertheless, the 400,000 IU (divided in two doses) supplementation showed a reduction in VAD
Resumo:
Vitamin A is important in many essential body processes and its deficiency results in serious consequences for human health. Breast milk is the only source of this vitamin for children that are exclusively breastfed. Analysis of vitamin A in mother s milk is important because its concentration is related to maternal vitamin A status and to its ingestion by the mother during pregnancy. The aim of the present study was to assess the effect of maternal supplementation with retynil palmitate on the concentration of colostrum retinol under fasting and postprandial conditions. A total of 149 nursing mothers were recruited at the Januário Cicco Maternity School (Natal, Brazil) and allocated to two groups: Comparison (n = 69) and Test (n = 80). Blood and colostrum (in fasting and postprandial conditions) samples were collected up to 24hs after delivery. Serum retinol and colostrum levels were analyzed by high-performance liquid chromatography. The serum retinol level of 41.6 ± 12.7μg/dL (mean ± standard deviation) indicates adequate biochemical nutritional status. Colostrum retinol level was not influenced by serum retinol levels under any of the conditions established. In the colostrum, the retinol concentration in the unsupplemented test group was 67.3 ± 37.7 μg/dL under fasting and 80.3 ± 35.1 μg/dL under postprandial conditions (p<0.05), showing an increase of 19.3%. In the supplemented test group the values were 102.6 ± 57.3 μg/dL and 133.4 ± 78.3 μg/dL under fasting and postprandial, respectively (p<0.05), representing an increase of 30%. Considering that under fasting conditions most of the vitamin A transported to the milk originates in the retinol binding protein (RBP), the postprandial increase in colostrum retinol suggests a different transport mechanism of retinol to maternal milk from that performed by RBP. This situation becomes more evident under supplementation conditions.
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Vitamins A and E are essential nutrients in many biological processes, so that their adequate supply to the neonate is crucial. However, the bioavailability of vitamins may be limited by factors such as maternal nutritional status and the interaction between nutrients. This study aimed to investigate the effect of biochemical nutritional status of retinol and alpha-tocopherol levels in serum and colostrum. The study included 103 healthy puerperal women treated at the reference state maternity hospital (Natal-RN). Colostrum and serum samples were collected fasting in the immediate postpartum period and the analysis of retinol and alpha-tocopherol were determined by high-performance liquid chromatography. Specific cutoff points were adopted to characterize the biochemical status of vitamins A and E. For the total group of lactanting women the average concentration of retinol in serum (1.49 ± 0.4 μmol/L-1) and colostrum (2.18 ± 0.8 μmol/L-1), as well as alpha-tocopherol in serum (26.4 ± 8.0 μmol/L-1) and colostrum (26.1 ± 12.8 μmol/L-1), indicated adequate biochemical state. However, when evaluating the individual, was found a high prevalence of deficient serum (15%) and colostrum retinol (50%), and also alphatocopherol in serum (16%) and colostrum (61%). In women with serum retinol ≥ 1.05 μmol/L-1, found an inverse correlation between serum retinol and alpha-tocopherol in colostrum (p = 0.008, r = -0.28). This association was not observed in women with serum retinol <1.05 μmol/L-1. This situation demonstrates for the first time in humans that high physiological levels of serum retinol, without supplementation, can negatively influence the transfer of alpha-tocopherol in breast milk. Although the diagnosis of satisfactory nutritional status lactanting women showed high risk of subclinical deficiency of vitamins A and E from measurements made in the colostrum
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El objetivo para la realización de éste Trabajo de Fin de Grado es la vehiculización en el sistema ternario Dehscodiol 462/agua/alcohol amílico de un producto dermocosmético (Vitamina F) y, a su vez, realizar un estudio de la influencia de la temperatura sobre la vehiculización en dicho sistema. Esta investigación se realiza para que en un futuro se pueda emplear el sistema de vehiculización aquí presentado, para solventar el aporte vitamínico necesario (o de cualquier otro principio activo que se desee) a través de un sistema de aplicación cutánea.
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Fragaria vesca L., morango silvestre, pertence à família das Rosaceae e é comumente encontrada nas bermas e taludes [1]. Os seus frutos pequenos e de sabor doce podem ser consumidos em fresco como uma fonte de vitamina C, ou em infusões muito utilizadas no tratamento de vários transtornos intestinais [2]. No presente trabalho, os frutos de F. vesca silvestre foram caracterizados em termos de valor nutricional (hidratos de carbono, proteínas, gordura, cinzas e valor energético), teor em fibra alimentar e perfil em ácidos gordos. Para além disso, os frutos e respetivas infusões foram também caracterizados pelo seu conteúdo em açúcares solúveis, ácidos orgânicos, folatos e tocoferóis por técnicas de HPLC acoplada a detectores de índice de refração, fotodíodos e fluorescência, respetivamente, e também pela sua composição mineral avaliada por espectroscopia de absorção atómica. Os hidratos de carbono foram os macronutrientes maioritários nos frutos, seguidos pela gordura total, cinzas e proteínas. Também demonstraram teores elevados em fibra alimentar, maioritariamente fibra solúvel. Os ácidos linolénico (C18:3n3) e γ-linolénico (C18:3n6) foram os ácidos gordos maioritários, havendo uma prevalência de ácidos gordos polinsaturados. Os frutos e as respetivas infusões apresentaram sacarose, seguida da frutose, como sendo os açúcares maioritários. O ácido cítrico foi o ácido orgânico mais abundante em ambas as amostras, enquanto os ácidos oxálico e ascórbico foram detetados nas infusões em concentrações vestigiais. Em termos de microelementos, o manganês foi o mais abundante em ambas as amostras; o potássio e o cálcio foram os macroelementos maioritários encontrados nos frutos e nas suas infusões, respetivamente. Em termos de vitaminas, ambas as amostras apresentaram folatos (vitamina B9) e tocoferóis (vitamina E), sendo o γ-tocoferol a isoforma mais abundante, seguido de α-tocoferol. É de referir que nas infusões foi somente encontrada a isoforma de α-tocoferol. Apesar dos frutos de F. vesca silvestre serem normalmente consumidos em fresco, este estudo prova a potencialidade das suas infusões como uma fonte de moléculas bioativas.
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Micronutrient deficiencies affect individuals mainly in developing countries, where vitamin A deficiency is a public health problem worldwide more worrying, especially in groups with increased physiological needs such as children and women of reproductive age. Vitamin A is supplied to the body through diet and has an important role in the visual process, cell differentiation, maintenance of epithelial tissue, reproductive and resistance to infection. The literature has demonstrated the relationship between vitamin A and diabetes, including gestational, leading to a risk to both mother and child. Gestational diabetes is any decrease in glucose tolerance of variable magnitude diagnosed each the first time during pregnancy, and may or may not persist after delivery. Insulin resistance during pregnancy is associated with placental hormones, as well as excess fat. Studies have shown that retinol transport protein produced in adipose tissue in high concentrations, this would be associated with resistance by interfering with insulin signaling. Therefore, this study aimed to evaluate the concentration of retinol in serum and colostrum from healthy and diabetic mothers in the immediate postpartum period. One hundred and nine parturient women were recruited, representing seventy-three healthy and thirty-six diabetic. Retinol was extracted and subsequently analyzed by High Performance Liquid Chromatography. Among the results highlights the mothers with gestational diabetes were older than mothers healthy, had more children and a higher prevalence of cases of cesarean section. Fetal macrosomia was present in 1.4% of healthy parturient women and in 22.2% of diabetic mothers. The maternal serum retinol showed an average of 39.7 ± 12.5 mg/dL for healthy parturients 35.12 ± 15 mg/dL for diabetic and showed no statistical difference. It was observed that in the group of diabetic had 17% vitamin A deficiency, whereas in the healthy group, only 4% of the women were deficentes. Colostrum, the concentration of retinol in healthy was 131.3 ± 56.2 mg/dL and 125.3 ± 41.9 mg/dL in diabetic did not differ statistically. This concentration of retinol found in colostrum provides approximately 656.5 mg/day for infants born to healthy mothers and 626.5 mg/day for infants of diabetic mothers, based on a daily consumption of 500 mL of breast milk and need Vitamin A 400 mg/day, thus reaching the requirement of the infant. The diabetic mothers showed significant risk factors and complications related to gestational diabetes. Although no 11 difference was found in serum retinol concentration and colostrum among women with and without gestational diabetes, the individual analysis shows that parturients women with diabetes are 4.9 times more likely to develop vitamin A deficiency than healthy parturients. However, the supply of vitamin A to the newborn was not committed in the presence of gestational diabetes
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Vitamin A deficiency is a serious public health problem in developing countries, and it causes death and blindness among children in the developing countries. The fortification of food could be an important source of vitamins to control deficiency. 60 Coturnix coturnix japonica quails were used in a randomized design with duration of seven weeks. The birds were assigned into five treatments with four repetitions. The objective was to evaluate the influence of the supplementation with different levels of retinyl palmitate (2,000 IU, 4,000 IU, 8,000IU and 16,000 IU) in quails under the levels of retinyl in egg yolks. The method used to dose retinyl in yolks of quail eggs was High Performance Liquid Chromatography and the enzymatic method to quantify the cholesterol concentration. The weight and production of eggs was significantly modified by the supplementation with retinyl in the birds. The results showed a gradual increase in the incorporation of retinyl in the egg yolk as a response to the supplementation, reaching values 384% higher than the control values. By the end of the supplementations a significant reduction in the concentrations of retinyl in the eggs yolk was observed. The most lasting supplementations were with 8,000 IU and 16,000 IU which lasted for three weeks. The cholesterol content in eggs was not significantly modified. The consumption of one egg enriched with 16000UI of retinol palmitate in the present study, by day, would probably reach 10 and 7,3% of the daily recommendations of this micronutrient for children of 1 to 3 years of age, and for 4 to 8 years, respectively. The nutritional value of eggs, related to the vitamin A, can be improved by supplementation of quails
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Despite advances in antibiotic therapy, bacterial meningitis (BM) remains with high mortality and morbidity rates in worldwide. One important mechanism associated to sequels during disease is the intense inflammatory response which promotes an oxidative burst and release of reactive oxygen species, consequently leading to cell death. Activation of DNA repair enzymes during oxidative stress has been demonstrated in several neurological disorders. APE1/Ref-1 is a multifunctional protein involved in DNA repair and plays a redox function on transcription factors such as NFkB and AP-1.The aim of this study was assess the role of APE1/Ref-1 on inflammatory response and the possibility of its modulation to reduce the sequels of the disease. Firstly it was performed an assay to measure cytokine in cerebrospinal fluid of patients with BM due to Streptococcus pneumoniae and Neisseriae meningitides. Further, a cellular model of inflammation was used to observe the effect of the inhibition of the endonuclease and redox activity of APE1/Ref-1 on cytokine levels. Additionally, APE1/Ref-1 expression in cortex and hippocampus of rat with MB after vitamin B6 treatment was evaluated. Altogether, results showed a similar profile of cytokines in the cerebrospinal fluid of patients from both pathogens, although IFNy showed higher expression in patients with BM caused by S. pneumoniae. On the other hand, inhibitors of APE1/Ref-1 reduced cytokine levels, mainly TNF-α. Reduction of oxidative stress markers was also observed after introduction of inhibitors in the LPS-stimulated cell. In the animal model, BM increased the expression of the protein APE1/Ref-1, while vitamin B6 promoted reduction. Thereby, this data rise important factors to be considered in pathogenesis of BM, e.g., IFNy can be used as prognostic factor during corticosteroid therapy, APE1/Ref-1 can be an important target to modulate the level of inflammation and VIII oxidative stress, and vitamin B6 seems modulates several proteins related to cell death. So, this study highlights a new understanding on the role of APE1/Ref-1 on the inflammation and the oxidative stress during inflammation condition
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Dissertação de Mestrado em Engenharia Zootécnica / Produção Animal