beta-Carotene is being used as an oral sun protectant, and evidence indicates that carotenoids may protect human skin from light-induced lesions. However, limited information is available on the distribution and accumulation of beta-carotene in skin, especially with respect to various skin regions. With the use of reflection spectroscopy, we investigated the accumulation of total carotenoids in human skin after repeated supplementation of 12 women with beta-carotene from a natural source Betatene, an algal extract. After daily ingestion of 24 mg beta-carotene (in Betatene) for 12 wk, an increase in carotenoid skin levels was observed. Highest basal values were measured in skin of the forehead, palm of the hand and dorsal skin, with lower levels measured in skin of the arm and back of the hand. Upon treatment, increases in carotenoid skin levels were found in all areas as follows: 2.4-fold in forehead, 0.7-fold in dorsal skin, 2.2-fold in the palm of the hand, 17-fold on the back of the hand and 1.7-fold on the inside of the arm. After cessation of treatment, the carotenoid levels decreased in all skin areas. Serum beta-carotene levels were elevated upon treatment and correlated with carotenoid skin levels. Correlations for serum vs. skin from the palm of the hand (r = 0.94) and skin from the forehead (r = 0.89) were calculated, indicating that serum levels appeared to be a suitable indicator for carotenoid accumulation in specific regions of the skin. With doses of approximately 20-25 mg carotenoids/d, it is possible to raise dermal carotenoid levels.
This pilot study could illustrate a good relation between the 2 methods for measuring hemoglobin. Larger studies are required to validate the spectroscopic method in those with conditions that affect the skin microcirculation (eg, septicemia).
Background: Venepuncture-related blood loss is a common cause of neonatal anemia. Currently, this is the only way to obtain hemoglobin levels. This causes distress for the infant but can also lead to the need for blood transfusions. Recently, a new technique for measuring hemoglobin levels non-invasively has been developed to reduce iatrogenic blood loss and pain. Objective: To compare hemoglobin levels obtained using a transcutaneous spectroscopic device (Mediscan 2000, MBR Optical Systems, Wuppertal, Germany) with venous or capillary blood samples in neonates. Methods: Single-center prospective cohort study of term and preterm infants. The white light spectroscopic device was placed on the forearm for 60 s to measure hemoglobin content within 4 h of venous or capillary blood sampling. Pain reactions of the infants were assessed by using a neonatal pain assessment tool. Results were analyzed by Bland-Altman comparison and Wilcoxon signed-rank test. Results: 80 infants (mean gestational age 29.8 ± 3.8 weeks, mean birth weight 1,300 ± 690 g) were enrolled into the study. A total of 313 spectroscopic recordings within 2 h of a clinically indicated blood sample (181 capillary, 142 venous) were taken. The correlation coefficient R2 was 0.96 for capillary/spectroscopic and 0.99 for venous/spectroscopic pairs. Pain scores were significantly less for the spectroscopic measurements (p < 0.01). Conclusion: The results show good correlation between the hemoglobin blood levels and spectroscopic measurements. The slightly lower correlation coefficient for the capillary samples demonstrates a naturally higher variance in these values due to the laboratory method.
SUMMARYThe aim of this study was to demonstrate that modification of the cellular redoxequilibrium occurs as a consequence of antioxidant nutrients intake (carotenoids, vitamine E and vitamine C) and that these nutrients play a role in the pigmentation of the skin without any UV exposure.We conducted a randomized, double-blind study in 20 healthy subjects to evaluate and to compare the efficacy of two mixtures of dietary antioxidants with regard to direct determination of melanin and carotenes by chromametry at selected skin sites and multiple reflection spectrometry from a 1 cm ~ region of skin of different parts of the body. Efficacy was assessed by a significant improvement of these parameters, in comparison with measurements performed on the day of randomization, before dietary supplement intake. The formulations per capsule of study dietary supplements are: 13 mg of 13-carotene, 2 mg of lycopene, 5 mg of vitamine E and 30 mg of vitamine C (B13/L2) or 3 mg of 13-carotene, 3 mg of lycopene, 5 mg of vitamine E and 30 mg of vitamine C (B3/L3).A 8-week B13/L2-supplementation lead to a detectable carotenodermia whereas the B3/L3-supplementation not.Signicative increase of melanin concentrations in skin were found after 4, 5, 6 and 8 weeks of dietary antioxidant intake in both groups (p<0.05). These results are discussed with regard to the redox control theory of melanocytes which regulates the tyrosinase activity.
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