background  it is remain a main concern that pediatric chest radiographies contribute to the significant radiation exposure to the thyroid gland as a more susceptible organ to radiation induced cancer. the aim of this study was to evaluate the entrance surface dose (esd) of pediatric chest radiography compared to the diagnostic reference levels (drl) and evaluation the efficacy of the lead (pb)...

BACKGROUND β-carotene is a carotenoid compound that has been widely used not only in the industrial production of pharmaceuticals but also as nutraceuticals, animal feed additives, functional cosmetics, and food colorants. Currently, more than 90% of commercial β-carotene is produced by chemical synthesis. Due to the growing public concern over food safety, the use of chemically synthesized β-c...

BACKGROUND Whereas conventional white cassava roots are devoid of provitamin A, biofortified yellow varieties are naturally rich in β-carotene, the primary provitamin A carotenoid. OBJECTIVE We assessed the effect of consuming yellow cassava on serum retinol concentration in Kenyan schoolchildren with marginal vitamin A status. DESIGN We randomly allocated 342 children aged 5-13 y to receiv...

BACKGROUND Despite vitamin A supplementation programs, vitamin A deficiency in children remains a public health concern in Honduras. AIM OF THE STUDY We investigated the effectiveness of short-term dietary supplementation of mothers with red palm oil as a strategy for improving the vitamin A status of the mother-infant dyad. METHODS Lactating mothers in Colonia Los Pinos, a barrio of Teguci...

BACKGROUND In two large, randomized prevention trials, supplementation with beta-carotene increased the risk of lung cancer. Subjects in these studies were predominantly cigarette smokers, and the adverse effects were concentrated among those who also drank alcohol. Although beta-carotene supplementation appeared not to increase the risk of cancer generally, it is not clear if smoking and/or al...

BACKGROUND Many epidemiologic studies have investigated the association between carotenoids intake and risk of Prostate cancer (PCa). However, results have been inconclusive. METHODS We conducted a systematic review and dose-response meta-analysis of dietary intake or blood concentrations of carotenoids in relation to PCa risk. We summarized the data from 34 eligible studies (10 cohort, 11 ne...

The extraction of lutein and β-carotene from spinach (Spinacia oleracea L.) leaves is important to the dietary supplement industry. A Box-Behnken design and response surface methodology (RSM) were used to investigate the effect of process variables on the ultrasound-assisted extraction (UAE) of lutein and β-carotene from spinach. Three independent variables, extraction temperature (°C), extract...

Milk produced at organic farms was studied to determine the β-carotene content and if an extended grazing period and organic fodder had any influence on the concentration of this antioxidant. Milk samples from 31 organic farms collected during April, June, August, November (1999) and February (2000) were analysed for the content of β-carotene by HPLC after lipid extraction and fat saponificatio...

The present study was conducted to clarify the relationship between colostral and plasma vitamin A and b-carotene, and to evaluate the effect of vitamin status on diarrhea and anemia of 46 Holstein newborn calves at 6 days of age. Colostral b-carotene and vitamin A concentrations at parturition ranged from 17.8 to 342.9 and from 32.9 to 450.0 mg/dl, respectively. Plasma b-carotene and vitamin A...

The accumulation off3-carotene in serum and skin was evaluated in human volunteers. A single S I -mg dose of 3-carotene given in the absence of dietary fat resulted in no detectable change in serum /3-carotene. The same dose administered with 200 g fat increased serum /3-carotene 2.5-fold at 40 h. Similarly, administering a-carotene daily in three divided doses with meals raised the serum /3-ca...