Standardized diaper care regimen: a prospective, randomized pilot study on skin barrier function and epidermal IL-1α in newborns.

Adaptation of skin barrier function and interleukin-1α (IL-1α) content in diapered and nondiapered skin are poorly characterized in newborns receiving standard skin care. In a monocentric, prospective pilot study 44 healthy, full-term neonates were randomly assigned to skin care with baby wipes (n = 21) or water-moistened washcloth (n = 23) at each diaper change. Transepidermal water loss (TEWL), skin hydration, skin-pH, IL-1α, and epidermal desquamation were measured on days 2, 14, and 28 postpartum. Microbiological colonization was evaluated at baseline and on day 28. Significantly lower TEWL was found on the buttock in the group using baby wipes compared to water. IL-1α and skin hydration significantly increased and pH decreased independent of skin care regimen. IL-1α was significantly higher in diapered skin compared to nondiapered skin. Although skin care with wipes seems to stabilize TEWL better than using water, the skin condition and microbiological colonization were comparable using both cleansing procedures. Increase of epidermal IL-1α may reflect postnatal skin barrier maturation. These data suggest that neither of the two cleansing procedures harms skin barrier maturation within the first four weeks postpartum. Longer observations on larger populations could provide more insight into postnatal skin barrier maturation.

Follicular and percutaneous penetration pathways of topically applied minoxidil foam.

In the past, it was assumed that the intercellular route was the only relevant penetration pathway for topically applied substances. Recent results on follicular penetration emphasize that the hair follicles represent a highly relevant and efficient penetration pathway and reservoir for topically applied substances. This study investigates a selective closure technique of hair follicle orifices in vivo assessing interfollicular and follicular absorption rates of topical minoxidil foam in humans. In delimited skin area, single hair orifices or interfollicular skin were blocked with a microdrop of special varnish-wax-mixture in vivo. Minoxidil foam (5%) was topically applied, and transcutaneous absorption was measured by a new surface ionization mass spectrometry technique in serum. Different settings (open, closed or none of both) enabled to clearly distinguish between interfollicular and follicular penetration of the topically applied minoxidil foam. Five minutes after topical application, minoxidil was detected in blood samples when follicles remained open, whereas with closed follicles 30 min were needed. Highest levels were found first when both pathways were open, followed by open follicles and subsequently by closed follicles. These results demonstrate the high importance of the follicular penetration pathway. Hair follicles are surrounded by a dense network of blood capillaries and dendritic cells and have stem cells in their immediate vicinity, making them ideal targets for drug delivery.