209 resultados para Retinol


Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of vitamin A supplementation, alone or in combination with other micronutrients (e.g. iron, folic acid, vitamin E), in mothers during the postpartum period, on maternal and infant health. Specific objectives are to compare the effects of vitamin A supplementation (alone or in combination with other micronutrients) with placebo or no supplementation on: 1. the duration and occurrence of maternal morbidity (xerophthalmia, infection) or illness symptoms (night blindness, fever, nausea, vomiting); 2. the duration and occurrence of neonatal or infant morbidity (respiratory tract infection, diarrhea, measles) or illness symptoms (fever, nausea, vomiting); 3. maternal serum retinol concentration; 4. infant serum retinol concentration; 5. breast milk retinol concentration; and 6. maternal satisfaction.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objectives To investigate the prevalence of anaemia and subclinical vitamin A deficiency among adolescent schoolboys in Dhaka City, Bangladesh, and to identify factors related to anaemia and vitamin A status. Design A cross-sectional study. Setting Government high schools in Dhaka City, Bangladesh. Subjects and methods A total of 381 boys, aged 11–16 years, from 10 schools in Dhaka City participated in the study. Socio-economic, anthropometric and dietary data were collected. Haemoglobin and serum retinol (vitamin A) concentrations were determined. Results Seven per cent of the boys were anaemic and 22% had serum vitamin A levels below the adequate level of 1.05 μmol l−1, with only 1.5% having subclinical vitamin A deficiency (

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objective: To assess validity of the Nambour food-frequency questionnaire (FFQ) relative to weighed food records (WFRs), and the extent to which selected demographic, anthropometric and social characteristics explain differences between the two dietary methods. Design: Inter-method validity study; 129-item FFQ vs. 12 days of WFR over 12 months. Setting: Community-based Nambour Skin Cancer Prevention Trial. Subjects: One hundred and fifteen of 168 randomly selected participants in the trial (68% acceptance rate) aged 25-75 years. Results: Spearman correlations between intakes from the two methods ranged from 0.18 to 0.71 for energy-adjusted values. Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least one characteristic for 16 of the 21 nutrients. Sex was significantly associated with differences for nine nutrients; body mass index (BMI), presence of any medical condition and age were each significantly associated with differences for three to six nutrients; use of dietary supplements and occupation were associated with differences for one nutrient each. There was no consistency in the direction of the significant associations. Regression models explained from 7% (riboflavin) to 27% (saturated fat) of variation in differences in intakes. Conclusions: The relative validity of FFQ estimates for many nutrients is quite different for males than for females. Age, BMI, medical condition and level of intake were also associated with relative validity for some nutrients, resulting in the need to adjust intakes estimates for these in modelling diet-disease relationships. Estimates for cholesterol, beta-carotene equivalents, retinol equivalents, thiamine, riboflavin and calcium would not benefit from this.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Previous studies indicate that regular consumption of a diet rich in fruits and vegetables is associated with a lower risk for age-related diseases. The aim of the present study was to evaluate whether the often-reported age-related decrease of plasma antioxidants in man depends on differences in dietary intake or on other age- and gender-related factors. In this observational case-control study, thirty-nine community-dwelling healthy subjects aged 65 years and older consuming high intakes of fruits and vegetables daily (HI) and forty-eight healthy subjects aged 65 and older consuming low intakes of fruit and vegetables daily (LI) were enrolled. Plasma levels of retinol, tocopherols, carotenoids and malondialdehyde (MDA) as well as content of protein carbonyls in Ig G were measured. Plasma levels of retinol, tocopherols and carotenoids were significantly higher in group HI than in group LI subjects independent of age and gender. MDA levels were inversely correlated with vitamin A and α-carotene. Protein carbonyls were inversely correlated with γ-tocopherol. In the elderly, a higher daily intake of fruits and vegetables is associated with an improved antioxidant status in comparison to subjects consuming diets poor in fruits and vegetables. Modification of nutritional habits among other lifestyle changes should be encouraged to lower prevalence of disease risk factors in later life. © The Authors 2005.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Arenesulfonic-acid functionalized SBA-15 materials have been used in the production of biodiesel from low grade oleaginous feedstock. These materials display an outstanding catalytic activity, being able to promote the transformation of crude palm oil with methanol into fatty acid methyl esters with high yield (85%) under mild reaction conditions. However, high sensitivity of the catalyst against poisoning by different substances has also been detected. Thus, alkaline metal cations, such as sodium or potassium exert a negative influence on the catalytic activity of these materials, being necessary amounts around 500 ppm of sodium in the reaction media to decrease the catalytic activity of these materials to a half of its initial value in just two reaction runs. The deactivation of arenesulfonic acid functionalized SBA-15 materials seems to occur in this case by ion exchange of the acid protons at the sulfonic groups. Organic unsaponifiable compounds like lecithin or retinol also induce a negative influence in the catalytic activity of these sulfonic acid-based materials, though not so intense as in the case of alkaline metals. The deactivating mechanism associated to the influence of the organic compounds seems to be linked to the adsorption of such substances onto the catalytic acid sites as well as on the silica surface. The accumulation of lecithin in the surface of catalyst, observed by means of thermogravimetric analysis, suggest the creation of a strong interaction, probably by ion pair, between this compound and the sulfonic acid group.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Vitamin A is an essential nutrient for many physiological processes such as growth and development, so that their adequate nutritional state is essential during pregnancy and lactation. Lactating women and children in breastfeeding are considered risk groups for vitamin A deficiency and some factors may increase the risk of vitamin A deficiency, such as prematurity. The aim of this work was to evaluate the vitamin A concentration in preterm and term lactating women and newborns by determination of retinol in maternal serum, umbilical cord serum and breast milk collected until 72 hours postpartum. 182 mothers were recruited and divided into preterm group (GPT; n = 118) and term group (GT, n = 64). In preterm group were also analyzed transition milk (7th-15th day; n = 68) and mature milk (30th-55th day; n = 46) samples. Retinol was analyzed by high-performance liquid chromatography (HPLC). Maternal retinol concentration in serum was 48.6 ± 12.3 µg/dL in GPT and 42.8 ± 16.3 µg/dL in the GT (p <0.01). Cord serum retinol was 20.4 ± 7.4 µg/dL in GPT and 23.2 ± 7.6 µg/dL in GT (p> 0.05). Among newborns, 43% of premature and 36% of term had low levels of serum retinol in umbilical cord (<20 µg/dL). In colostrum, the retinol in preterm and term groups had an average of 100.8 ± 49.0 µg/dL and 127.5 ± 65.1 µg/dL, respectively (p <0.05). The retinol average in preterm milk increased to 112.5 ± 49.7 µg/dL in transition phase and decreased to 57.2 ± 23.4 µg/dL in mature milk, differing significantly in all stages (p <0.05). When comparing with the recommendation of vitamin A intake (400 µg/day) GT colostrum reached the recommendation for infants, but in GPT the recommendation was not achieved at any stage. Mothers of premature infants had higher serum retinol than mothers at term; however, this was not reflected in serum retinol of umbilical cord, since premature had lower concentration of retinol. Such condition can be explained due to lower maternal physiological hemodilution and placental transfer of retinol to the fetus during preterm gestation. Comparison of retinol in colostrum showed lower concentrations in GPT; however the transition phase there was a significant increase of retinol content released by the mammary gland of preterm mothers. This situation highlights a specific physiological adaptation of prematurity, likely to more contribute to formation of hepatic reserves of retinol in premature infants.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

El estudio de la relación entre componentes de la dieta y la salud/enfermedad utiliza métodos de valoración de la ingesta dietética, del estatus nutricional y de marcadores de función o de efecto. En concreto, en el estudio de los carotenoides y la salud ocular, interesa el estudio de dos carotenoides sin actividad provitamina A, la luteína y la zeaxantina, por su posible papel en la optimización de la función visual y en la prevención de enfermedades crónicas asociadas a la edad, y de tres carotenoides con actividad provitamina A: -caroteno, -caroteno y -criptoxantina, por ser precursores de retinol, nutriente del que depende el ciclo visual para una visión normal. En el presente trabajo se ha llevado a cabo el estudio de los carotenoides de la dieta más relevantes para la salud ocular humana considerando de forma simultánea parámetros relacionados con la ingesta, el estatus y la función visual, así como diversas variables que pueden modificar el estatus nutricional, como son la concentración de lípidos en sangre, y la bioaccesibilidad de los carotenoides a partir de alimentos de amplio consumo...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Mothers with good vitamin A nutritional status during gestation and lactation are better able to nourish and protect their infant with maternal milk. Our hypothesis is that women with more serum retinol have more retinol and secretory immunoglobulin A in colostrum. 190 healthy puerperal women from a Brazilian public maternity were recruited and divided according to the cutoff point for serum retinol (30 μg/dL). A number of the women was supplemented with 200000 UI (60 mg) of retinyl palmitate in the immediate postpartum. Serum and colostrum were collected on the 1st day postpartum and colostrum again on the following day. Retinol (serum and colostrum) was analyzed by HPLC and SIgA (colostrum) by turbidimetry. The mothers presented with adequate biochemical indicators of nutritional status, according to serum retinol (44.6 μg/dL). There were significant differences (p= 0.0017 and p= 0.043, respectively) in retinol and SIgA levels in the colostrum of mothers with serum retinol > 30 μg/dL and < 30 μg/dL. The concentration of SIgA in the colostrum of non-supplemented mothers on the 1st day postpartum was 822.6 mg/dL, decreasing after 24 hours to 343.7 mg/dL. Supplemented mothers showed levels of SIgA in colostrum of 498.9 mg/dL on the 2nd day postpartum (p= 0.00006). The colostrum of women with good vitamin A nutritional status had more retinol and SIgA. Additionally, maternal supplementation increases the levels of SIgA in colostrum. The higher levels of SIgA on the 1st day postpartum showed the importance of early breastfeeding, given that it provides considerable immunological benefits to newborn infants

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Nutritional status is an important determinant to the response against Leishmania infection, although few studies have characterized the molecular basis for the association found between malnutrition and the disease. Vitamin A supplementation has long been used in developing countries to prevent mortality by diarrheal and respiratory diseases, but there are no studies on the role of vitamin A in Leishmania infection, although we and others have found vitamin A deficiency in visceral Leishmaniasis (VL). Regulatory T cells are induced in vitro by vitamin A metabolites and are considered important cells implicated T CD4+ cell suppression in human VL. This work aimed to examine the correlation of nutritional status and the effect of vitamin A in the response against Leishmania infantum infection. A total of 179 children were studied: 31 had active VL, 33 VL history, 44 were DTH+ and 71 were DTH- and had negative antibody to Leishmania (DTH-/Ac-). Peripheral blood monuclear cells were isolated in a subgroup of 10 active VL and 16 DTH-/Ac- children and cultivated for 20h under 5 different conditions: 1) Medium, 2) Soluble promastigote L. infantum antigens (SLA), 3) All-trans retinoic acid (ATRA), 4) SLA + ATRA and 5) Concanavalin A. T CD4+CD25highFoxp3+, T CD4+CD25-Foxp3- and CD14+ monocytes were stained and studied by flow cytometry for IL-10, TGF-β and IL-17 production. Nutritional status was compromised in VL children, which presented lower BMI/Age and retinol concentrations when compared to healthy controls. We found a negative correlation between nutritional status (measured by BMI/Age and serum retinol) and anti-Leishmania antibodies and acute phase proteins. There was no correlation between nutritional status and parasite load. ATRA presented a dual effect in Treg cells and monocytes: In healthy children (DTH-/Ac-), it induced a regulatory response, increasing IL-10 and TGF-β production; in VL children it modulated the immune response, preventing increased IL-10 production after SLA stimulation. Furthermore, we found a positive correlation between BMI/Age and IL-17 production and negative correlation between serum retinol and IL-10 and TGF-β production in T CD4+CD25highFoxp3+ cells after SLA stimulus. Our results show a potential dual role of vitamin A in the immune system: improvement of regulatory profile during homeostasis and down modulation of IL-10 in Treg cells and monocytes during symptomatic VL. Therefore, the use of vitamin A concomitant to VL therapy might improve recovery from disease status in Leishmania infantum infection

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The mothers supplementation of vitamin A in the postpartum comes being a measure of intervention sufficiently used in the combat to the vitamin deficiency. The objective of this work was to evaluate the effect of the mother megadose of vitamin A under the levels of retinol in colostrum of postpartum mothers receiving care at the Januário Cicco Maternity School (MEJC), Natal, RN, as well as analyzing the influence of the maternal nutritional status in the reply to this supplementation. The study it was transversal type, with participation of 91 women in labor divided in group had participated of the study have controlled (44 women) and supplemented group (47 women). In the period of the morning blood and milk had been collected (milk 0h). After that a capsule of retinil palmitate of (200 000 UI or 60 mg) was supplied to the supplemented group. Another aliquot of colostro was after gotten 24h of the first collection (milk 24h). Retinol in milk and serum was quantified through the High Pressure Liquid Chromatography. The vitamin ingestion was evaluated by the questionnaire of frequency of alimentary consumption. The levels of serum retinol were 40.6 ± 10.6 and 35.9 ± 10.9 µg/dL in the groups controlled and supplemented, respectively. The women had presented a satisfactory average ingestion of vitamin (1492,4 µgRAE/dia), however with high prevalence of inadequate consumption (23%). Average values of retinol in milk 0h had been found and 24h of 93.5 ± 50.3 µg/dL and 99.1 ± 49.3 µg/dL has the group controlled group, respectively (p>0.05). After the supplementation had a significant increase in the levels of retinol of the supplemented group, being found values of 102.0 ± 56.0 µg/dL and 196.1 ± 74.0 µg/dL for milk 0h and 24h, respectively (p<0.0001). The women in labor presented different answers to the supplementation influenced for the basal levels of retinol in colostrum. It was possible to verify that women with deficient levels of retinol in milk had transferred more retinol to milk 24h than ones with adjusted levels, showing a percentage of reply equivalent to 326.1% and 86.5% of increase, respectively (p< 0.0001). Although the apparent normality found in the serum, the studied women are considered of risk to the development of the vitamin deficiency, and megadose was efficient in first 24h after the supplementation and wakes up with the mechanisms considered for transference of vitamin A to the milk

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Propósito y Método del Estudio: Determinar los perfiles de expresión de proteínas en orina en pacientes agrupados de acuerdo a las complicaciones presentadas post trasplante (TR) y detectar su variación al modificar la terapia. Fue un estudio observacional, longitudinal, analítico y retrospectivo. Se incluyeron pacientes que fueron sometidos a trasplante y estuvieron de acuerdo en participar en el protocolo. Se recolectaron muestras de orina pretrasplante y cada tercer día desde el momento del trasplante. Las muestras fueron almacenadas a -70ºC hasta el momento de su análisis por marcaje peptídico mediante isótopos isobáricos para la cuantificación relativa (iTRAQ). Se agrupó a los pacientes con complicaciones por infección confirmado por cultivos y rechazo agudo confirmado por biopsia. Se establecieron 4 fases de estudio: pre trasplante, post TR previo a complicación, post TR con complicación en curso y post TR complicación tratada. Contribuciones y Conclusiones: De Enero de 2009 a Mayo de 2013 se incluyeron a 22 pacientes: 10 mujeres (45%) y 12 hombres (55%) con una edad promedio de 45+ 15 años. Solo 12 pacientes presentaron complicaciones en el post TR: 2 pacientes con rechazo agudo al injerto (GR) (1hombre, 1 mujer); y 10 pacientes (6 hombres, 4 mujeres) en el grupo de infecciones (GI). Para el análisis por iTRAQ se hizo la cuantificación relativa comparando la presencia de las proteínas en las diferentes fases de estudio. Para el grupo de rechazo agudo, se encontraron 345 proteínas, de las cuales solo 15 cumplieron los criterios de aceptación de la técnica (score >30, > 2 péptidos identificados con el 95% de confianza). Para el grupo de infecciones se encontraron 113 de las cuales 28 cumplieron los criterios de aceptación de la técnica. Conclusiones: La albúmina fue la única proteína encontrada en ambos grupos de estudio, el resto de las proteínas 14 en el GR y 27 en GI fueron diferentes. Las 5 proteínas con mayor scores en GR fueron alfa 1 microglobulina, 5' nucleosidasa citosólica, Proteína 4 de unión a retinol, proteína de membrana 4 palmitolada y serin carboxipeptidasa mientras que en GI: acetil coenzima A sintetasa mitocondrial, adenosil homocisteinasa 2, proteína de dedo de zinc GLIS1isoforma X1, proteína putativa de la isoforma FAM157B, proteína de dedo de zinc 615 isoforma X6. Queda por dilucidar la participación de cada una de éstas en los pacientes con trasplante renal.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Introduction: Nonagenarian population, clearly increasing, shows different characteristics from the rest of elderly people. Health-related quality of life is a way to study population health in physical, psychological and social dimensions. Objectives: To examine the relationship between nutritional status and health-related quality of life in a group of free-living nonagenarians. Differences with octogenarians were also studied. Methods: Within Villanueva Older Health Study, 20 non-institutionalised people (92.5±3.5 years; 80% women) make the nonagenarian subsample. Nutritional risk was assessed by Mininutritional Assessment questionnaire, dietary intake by a 24-hour dietary recall and health-related quality of life by EuroQoL-5D questionnaire. SPSS was used for statistical analysis. Results: 40% nonagenarians were at risk of malnutrition. Dietary assessment showed magnesium, zinc, potassium, folic acid, vitamin D and vitamin E deficiencies. Problems in mobility were more frequently reported (80%). EQ-5Dindex was associated with MNA (p<0.05). Self-care dimension was associated with calcium and niacin (p<0.05), retinol and cholesterol (p<0.01) intake. Usual activities dimension was associated with niacin (p<0.01) and cholesterol(p<0.05) intake. Pain/discomfort dimension was associated with protein (p<0.01), energy, selenium and niacin (p<0.05) intake. Anxiety/depression was associated with protein(p<0.01) and selenium (p<0.05) intake. Conclusions: Risk of malnutrition is a factor associated to health-related quality of life. Results suggest that energy and some nutrient intakes could be possibly associated to health-related quality of life but further research on this influence is required.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Vitamin A (VA) deficiency (VAD) is a major nutritional public health problem among children under-5-years-old in the developing world including Kenya. A community-based cross-sectional survey among 1,630 children (aged 6-23 mos) was undertaken in Western Kenya. A questionnaire was administered to collect demographic, socio-economic and dietary intake information. Prevalence of low retinol-binding protein (RBP) concentrations was assessed using Dried Blood Spot (DBS) methodology. Analysis of RBP was carried out using rapid enzyme immunoassay (EIA) and C-reactive protein (CRP) was carried out using enzyme linked immunosorbent assay (ELISA) to estimate VA and sub-clinical inflammation statuses, respectively. Values were adjusted for influence of inflammation using CRP (CRP >5 mg/L) and population prevalence of VAD (RBP <0.825 μmol/L, biologically equivalent to 0.70 μmol/L retinol) estimated. Anthropometric data gave three indices: stunting, wasting and underweight—all of which took age and sex into consideration. Mean (geometric± SD) concentration of RBP was adequate (1.56±0.79μmol/L) but the inflammation-adjusted mean (±SE) prevalence of VAD was high (20.1±1.1%) in this population. The level of CRP was within normal range (1.06±4.95 mg/L) whilst 18.4±0.9% of the children had subclinical inflammation (CRP>5 mg/L). Intake of VA capsule (VAC) by a child was a predictor of VAD with children who have not taken VA during the past 1 year prior to the survey having a 30% increased risk of VAD (OR (CI): 1.3 (1.1-1.7); p=0.025. Additionally, age of the child was a predictor with older children (18-23 mos) having a 30 % increased risk of VAD (OR (CI): 1.3 (1.1-1.9); p=0.035); the caretaker’s knowledge on VA and nutrition was also a predictor of VAD with children whose caretaker’s had poor knowledge having a 40 % increased risk of VAD (OR (CI): 1.4 (1.0-1.9); p=0.027. A child’s district of residence was also a significant predictor of VAD. Prevalence of VAD in this sample of infants was high. Predictors of VAD included child intake of VAC in the last 1 year before the survey, older children, children whose caretakers had poor VA and nutritional knowledge and a child’s district of residence. There is a need to improve knowledge on nutrition and VA of caretakers; undertake a targeted VAC distribution, particularly in children older than 1 year and above and use a sustainable food-based intervention in the areas with severe VAD.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Foram conduzidos experimentos de competição entre cultivares de mandioca (Manihot esculenta Crantz) em ecossistema de terra firme (Manaus - Amazonas), com objetivo de obter melhores cultivares de mandioca com relação a produtividade e teor de caroteno pró-vitamínico A. Raízes de sete cultivares de mandioca amarela foram selecionadas para identificação e quantificação de carotenos com atividade de vitamina A, mediante o método descrito por Rodriguez. Observou-se, também, as perdas de pró-vitamina A pelo processamento e armazenamento de farinha. Constatou-se a presença de três isômeros do beta - caroteno (o 13 - eis -beta - caroteno, o beta - caroteno todo trans e o 9 - eis -beta - caroteno U). Quanto aos teores de vitamina A, expressos em equivalente de retinol, nas raízes variaram de 4,4 a 18,8. Com relação a perda de atividade da vitamina A pelo processamento variou de 25,0 a 40,0 %, enquanto que o armazenamento por 6 meses em sacos plásticos transparentes, à temperatura ambiente e à exposição de luz, resultou em degradação total de seus carotenóides. Os resultados permitem concluir que três cultivares (IM 232; IM 104 e BGM 021) apresentaram os maiores teores de pró-vitamina A.