Neena Tierney

Diaper dermatitis: etiology, manifestations, prevention, and management.

Pediatricians and parents report diaper dermatitis (DD) to be one of the most common skin diseases that affects almost every child at some point during the early months and years of life. Diapered skin is exposed to friction and excessive hydration, has a higher pH than nondiapered skin, and is repeatedly soiled with feces that contains enzymes with high irritation potential for the skin. The combination of these factors frequently results in skin damage, leading to visible erythematous lesions that can be irritating and painful to the child. Behavioral changes such as increased crying and agitation and changes in eating and sleeping patterns indicate emotional distress. Appropriate skin care can help to prevent the occurrence of DD and to speed up the healing of affected skin. This includes frequent diaper changes and aeration, gentle cleansing, and the use of a barrier cream. Mild to moderate cases usually resolve after a few days of following this routine, but the use of harsh cleaning products can exacerbate DD.

Development of Solar UVR-Related Pigmentation Begins as Early as the First Summer of Life

regenerated from intact melanophores. At 0.9 J cm 2 fluence, destroyed melanophores should be generated from stem cells, and they therefore required more time to regenerate in our study. Melanosomes in melanophores of adult zebrafish normally have a round or slightly ellipsoid shape (Hirata et al., 2005). In contrast, the damaged melanosomes in our study appeared shrunken or cracked after laser irradiation (Supplementary Figure S2 online). With the exception of the melanosomes, no other cells were observed to be damaged by transmission electron microscopy. Xanthophores—the source of the yellow stripes on zebrafish skin—are hypothesized to act as a barrier delimiting the area that can be occupied by melanophores. The interactions between these two types of chromatophores are an important focus in the study of zebrafish pigmentation patterns (Takahashi and Kondo, 2008). After Q-switched Nd:YAG laser irradiation, intact xanthophores were detected (Supplementary Figure S3 online). Recently, attempts have been made to use the 1064-nm Q-switched Nd:YAG laser with short pulse duration and low fluence for the treatment of melasma (Jeong et al., 2008; Polnikorn, 2008; Chung et al., 2009; Kim et al., 2009). With short pulse duration and low fluence, the laser could selectively photothermolyse melanosomes without killing melanocytes. This might prevent postinflammatory hyperpigmentation after melanocyte destruction, which is especially common in Asians (Ho and Chan, 2009). In addition, our study offers a convenient technique to destroy melanosomes in adult zebrafish. The Qswitched Nd:YAG laser can be used to remove melanosomes without affecting melanophores or other cells at the following settings : 1064 nm wavelength, 5–7 ns pulse duration, 7 mm spot size, and 0.4 J cm 2 fluence. Although they are very specific settings, and subtle changes might therefore invalidate the use of this model, the approaches used here may be helpful for the study of melanocyte biology with zebrafish.

Update on Infant Skin with Special Focus on Dryness and the Impact of Moisturizers

Throughout infancy, skin differs from that of an adult in structure, function, and composition and has water-handling properties that are markedly distinct. Although competent to prevent dehydration, immature skin barrier function leaves infants especially vulnerable to the environment with potential for development of skin irritations elicited, for example, by contact with allergens or exposure to harsh climatic conditions. To this is added a relatively high risk for the development of the inflammatory disease atopic dermatitis. Specially formulated moisturizers are thus needed that respect the specific properties of infant skin and protect it by enhancing the barrier properties without interfering with the natural development.

Using Novel In Vitro NociOcular Assay based on TRPV1 channel activation for Prediction of Eye Sting Potential of Baby Shampoos

The transient receptor potential vanilloid type 1 (TRPV1) channel is one of the most well-characterized pain-inducing receptors. The purpose of this study was to predict human eye stinging of 19 baby bath and shampoo formulations by studying TRPV1 activity, as measured by increase in intracellular free Ca(2+). The NociOcular test, a novel recombinant neuronal in vitro model with high expression of functional TRPV1 channels, was used to test formulations containing a variety of surfactants, preservatives, and fragrances. TRPV1-specific Ca(2+) influx was abolished when the TRPV1 channel antagonist capsazepine was applied to the cells prior to shampoo samples. The positive control, an adult shampoo that contains cocamide monoethanolamine (CMEA), a known stinging ingredient, was the most active sample tested in the NociOcular test. The negative control, a marketed baby shampoo, was negative in the NociOcular and human tests. Seven of the formulations induced stinging in the human test, and of those six were positive in the NociOcular test. Twelve formulations were classified as nonstinging in the human test, and of those ten were negative in the NociOcular test. There was no correlation between the clinical stinging results for the baby formulations and the data generated from other in vitro eye irritation assays (cytosensor microphysiometer, neutral red uptake, EpiOcular, transepithelial permeability). Our data support that the TRPV1 channel is a principal mediator of eye-stinging sensation induced by baby bath and shampoo formulations and that the NociOcular test may be a valuable in vitro tool to predict human eye-stinging sensation.

Estimating infants’ and toddlers’ inhalation exposure to fragrance ingredients in baby personal care products

ABSTRACT Fragrance ingredients are commonly added to many personal care products to provide a pleasant scent, including those intended for babies. While fragrance chemicals have a long history of safe use, at sufficiently high concentrations some may act as respiratory irritants or sensitizers. Little data have been reported on the inhalation exposures to fragrance compounds to infants and toddlers during bathing and lotion applications. This study demonstrates an in vitro method for measuring breathing zone air concentrations of fragrances from bath products and lotions. It employed simulated infant bathing and lotion application events and a robot to mimic a toddler’s movement within a bathroom setting. The air concentrations in an infant’s breathing zone were between <1 and 5 μg/m3 for each of seven common fragrance ingredients, while that in the breathing zone of toddlers in the bathroom was ≤ 1μg/m3. The air concentrations from the bathing additive were linearly related to their Henry’s law constants and from the lotion inversely related to their octanol-air coefficients. The proposed approach can help refine risk estimates from inhalation exposure to fragrances used in baby products and guide future risk assessments of new products’ safety for their use in baby bath products.