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Serum Retinol (serum + retinol)
Terms modified by Serum Retinol Selected AbstractsVitamin A: Is It a Risk Factor for Osteoporosis and Bone Fracture?NUTRITION REVIEWS, Issue 10 2007Judy D. Ribaya-Mercado ScD Results from observational studies of the association between vitamin A intake or serum concentration and bone mineral density or fracture are mixed. The inconsistencies may be due, in part, to difficulties in obtaining an accurate assessment of vitamin A intake or status. Serum retinol is a poor measure of vitamin A status because it is subject to homeostatic control. Stable-isotope-dilution methodology gives a validated assessment of the total-body and liver vitamin A stores and is recommended in future studies on vitamin A status and osteoporosis. The potential for exacerbating an already serious public health problem with intakes of vitamin A currently considered safe indicates further research into this matter is warranted. [source] Comparison of indices of vitamin A status in children with chronic liver disease,HEPATOLOGY, Issue 4 2005Andrew P. Feranchak Malabsorption of fat-soluble vitamins is a major complication of chronic cholestatic liver disease. The most accurate way to assess vitamin A status in children who have cholestasis is unknown. The goal of this study was to assess the accuracy of noninvasive tests to detect vitamin A deficiency. Children with chronic cholestatic liver disease (n = 23) and noncholestatic liver disease (n = 10) were studied. Ten cholestatic patients were identified as vitamin A,deficient based on the relative dose response (RDR). Compared with the RDR, the sensitivity and specificity to detect vitamin A deficiency for each test was, respectively: serum retinol, 90% and 78%; retinol-binding protein (RBP), 40% and 91%; retinol/RBP molar ratio, 60% and 74%; conjunctival impression cytology, 44% and 48%; slit-lamp examination, 20% and 66%; tear film break-up time, 40% and 69%; and Schirmer's test, 20% and 78%. We developed a modified oral RDR via oral coadministration of d-alpha tocopheryl polyethylene glycol-1000 succinate and retinyl palmitate. This test had a sensitivity of 80% and a specificity of 100% to detect vitamin A deficiency. In conclusion, vitamin A deficiency is relatively common in children who have chronic cholestatic liver disease. Our data suggest that serum retinol level as an initial screen followed by confirmation with a modified oral RDR test is the most effective means of identifying vitamin A deficiency in these subjects. (HEPATOLOGY 2005;42:782,792.) [source] Serum antioxidant micronutrient levels in oral lichen planusJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 5 2001Toru Nagao Abstract: The aim of this study was to elucidate any association between oral lichen planus (OLP) and serum antioxidant micronutrients by a population-based case-control study. A total of 9536 subjects were examined, and 62 (58 reticular, 4 atrophic and erosive) diagnosed with OLP at referral facilities were compared with four controls per case (n=248) selected among disease-free subjects matched for age and sex. Serum levels of micronutrients (retinol, ,-tocopherol, zeaxanthin/lutein and cryptoxanthin, lycopene, ,-carotene and ,-carotene) were estimated by the high performence liquid chromatography (HPLC) method. Among cases, mean serum retinol level (2.820±0.849 ,mol/l) was significantly higher compared with that of controls (2.562±0.735 ,mol/l) (P<0.05). No significant differences were noted in carotenoid levels examined in this study, except for a lower level of lycopene found in atrophic/erosive OLP cases. The results of this study suggest that low serum retinol or carotenoid levels are not risk factors for occurrence of lichen planus, and any specific benefits of antioxidant micronutrients cannot be claimed for this inflammatory disorder. [source] Carotenoids in yellow- and red-fleshed papaya (Carica papaya L)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2003U Gamage Chandrika Abstract Vitamin A deficiency is a disorder of public health importance in Sri Lanka. A recent national survey revealed that 36% of preschool children in Sri Lanka have vitamin A deficiency (serum retinol <0.2 µg ml,1). In view of its well-established association with child morbidity and mortality, this is a reason for concern. One of the main fruits which has been recommended for prevention of vitamin A deficiency in Sri Lanka is papaya (Carica papaya L). In this study the carotenoid profiles of yellow- and red-fleshed papaya were analysed by medium-pressure liquid chromatography (MPLC) and UV-vis spectrophotometry. A section of yellow-fleshed papaya showed small carotenoid globules dispersed all over the cell, whereas in red-fleshed papaya the carotenoids were accumulated in one large globule. The major carotenoids of yellow-fleshed papaya were the provitamin A carotenoids ,-carotene (1.4 ± 0.4 µg g,1 dry weight (DW)) and ,-cryptoxanthin (15.4 ± 3.3 µg g,1 DW) and the non-provitamin A carotenoid ,-carotene (15.1 ± 3.4 µg g,1 DW), corresponding theoretically to 1516 ± 342 µg kg,1 DW mean retinol equivalent (RE). Red-fleshed papaya contained the provitamin A carotenoids ,-carotene (7.0 ± 0.7 µg g,1 DW), ,-cryptoxanthin (16.9 ± 2.9 µg g,1 DW) and ,-carotene-5,6-epoxide (2.9 ± 0.6 µg g,1 DW), and the non-provitamin A carotenoids lycopene (11.5 ± 1.8 µg g,1 DW) and ,-carotene (9.9 ± 1.1 µg g,1 DW), corresponding theoretically to 2815 ± 305 µg kg,1 DW mean RE. Thus the carotenoid profile and organisation of carotenoids in the cell differ in the two varieties of papaya. This study demonstrates that carotenoids can be successfully separated, identified and quantified using the novel technique of MPLC. Copyright © 2003 Society of Chemical Industry [source] Impaired bioavailability of vitamin A in adults and children with persistent diarrhoea in ZambiaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2001P. Kelly Background: We have previously demonstrated a strong relationship between low serum retinol concentration and mortality in Zambian AIDS patients with diarrhoea, but were unable to detect any benefit from oral micronutrient supplementation. Aim: To test the hypothesis that this is related to impaired availability of vitamin A, we analysed serum retinol concentration changes over 6 h following oral mega-dose therapy (60, 120 or 180 mg retinol). Methods: Twenty-four men without diarrhoea, 15 adults with persistent diarrhoea and 11 children (six girls, five boys) with persistent diarrhoea were studied. Results: Men with persistent diarrhoea had lower baseline serum retinol concentrations (median 0.39 ,mol/L, interquartile range 0.21,0.56) than controls (median 1.16 ,mol/L, interquartile range 0.84,1.47; P=0.0003). After 60 mg retinol, the rise in serum retinol in HIV seropositive controls (median 0.63 ,mol/L, interquartile range 0.35,0.77) did not differ significantly from that observed in HIV seronegative controls (median 0.35 ,mol/L, interquartile range , 0.04,0.56; P=0.20). Increasing the dose to 120 mg or 180 mg retinol did not enhance the increase in serum retinol concentration. The increase in serum retinol was less in adults with persistent diarrhoea (median 0.25 ,mol/L, interquartile range 0.04,0.35) and in children (median 0.11 ,mol/L, interquartile range 0.04,0.46) than in men without diarrhoea (median 0.44 ,mol/L, interquartile range 0.26,0.74; P=0.03). Adults and children with diarrhoea had greater losses of retinol in urine over a 24-h period than controls, but less than 1% of the ingested dose was excreted. Conclusions: These results suggest that persistent diarrhoea in this population is associated with reduced bioavailability of retinol. Further work is required to determine the metabolic fate of therapeutic doses of retinol and to determine appropriate replacement strategies for HIV infected individuals. [source] Vitamin A deficiency in healthy children aged 6,59 months in ,zmir Province of TurkeyPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2000Kurugöl Vitamin A deficiency even at subclinical levels is associated with increased childhood mortality. There have been few studies related to vitamin A status of children in Turkey. The aim of this study was to assess vitamin A status of children aged 6,59 months in ,zmir, Turkey, and to evaluate the relationship of these levels with nutritional status. One hundred and sixty children were selected for the study using the cluster sampling method. Serum retinol levels were measured by high-performance liquid chromatography (HPLC) and ranged from 9.8 to 59.2 ,g/dL (mean 29.3 ± 9.5 ,g/dL). Levels were below the lower limit of the normal range in 15.6% of the children. Deficient and marginal serum retinol among stunted children were observed in 16% and 42% respectively. There was a statistically significant relationship between low serum retinol and stunting (P < 0.05). Although xerophthalmia and other clinical signs of vitamin A deficiency are rarely seen, subclinical vitamin A deficiency is a public health problem in ,zmir, Turkey. [source] Effects of vitamin A deficiency during pregnancy on maternal and child healthBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 6 2002M.S. Radhika Objective To examine the association between biochemical vitamin A deficiency in pregnancy and maternal and fetal health. Design A cross sectional clinical study. Setting Antenatal clinic of nutrition unit of Niloufer Hospital catering for a low socio-economic population, and a private nursing home (Swapna nursing home) catering for a high socio-economic population. Population 736 pregnant women in their third trimester of pregnancy belonging to low (n= 522) and high socio-economic groups (n= 214). Methods All the women were subjected to a detailed clinical, anthropometric and obstetric examination. Night blindness was assessed by administering the standard WHO questionnaire. Birthweight and gestational age of the infants, maternal anaemia and development of pregnancy-induced hypertension in the mother were recorded. Haemoglobin and serum retinol were estimated at the time of recruitment to the study. Main outcome measures Serum retinol levels, anaemia, pregnancy-induced hypertension, birthweight and gestational age of the infant. Results Night blindness was observed in 2.9% of the women and subclincal vitamin A deficiency (serum retinol <20 ,g/dL with no clinical signs) in 27% of the women. Moderate to severe anaemia was observed in 41.2% of the women, and 15.8% of the women developed pregnancy-induced hypertension. Sixty-one (9.4%) women delivered preterm. Univariate analysis identified a significant association between serum retinol <20 ,g/dL and preterm delivery (OR = 1.74, 95% CI 1.03,2.96), maternal anaemia (OR = 1.82, 95% CI 1.28,2.60) and pregnancy-induced hypertension (OR = 1.56, 95% CI 1.02,2.83). After adjusting for the confounding variables (body mass index, parity, age and socio-economic status) in a multivariate analysis, the significant associations between serum retinol <20 ,g/dL and preterm delivery (P= 0.02) and anaemia (P= 0.003) persisted, while that for pregnancy-induced hypertension disappeared (P= 0.71). Conclusion The study suggests that subclinical vitamin A deficiency is a problem during the third trimester of pregnancy. Serum concentration of retinol <20 ,g/dL appears to indicate a deficient status, and is associated with an increased risk of preterm delivery and maternal anaemia. [source] | ||||||||||