DESCRIPTION (Adapted from the application): The human epidermis is a complex biological membrane which forms the interface for multiple nursing interventions. Knowledge of the dynamic structure, changing function, and biomechanical limits of the epidermis and its ultimate product, the stratum corneum, is important in determining therapy aimed at thermal support, fluid balance, prevention of infection, and wound management. The development of individualized skin care protocols aimed at maintenance of epidermal barrier function and prevention/restoration of barrier breakdown requires early and accurate detection methods as well as knowledge of normal state. Such protocols can be guided by noninvasive bedside sensing technologies targeted to specific molecular bases of skin structure and function. This proposal is specifically focused on the development of the epidermal barrier in human infants (25-40 weeks gestation). Methodologically, it is hypothesized that the maturation of the stratum corneum/vernix interface and formation of a hydrophobic skin surface will be closely linked to development of the epidermal acid mantle. Measurement of these two superficial physical attributes (hydrophobicity and surface acidity) will be performed using noninvasive, bioelectronic sensing systems with on-line data acquisition at the bedside. These measurements will be complemented by ultrastructural and lipid biochemical compositional studies of the outermost epidermal surface layer performed at selected body sites using noninvasive techniques. The hypothesis of a race difference in epidermal barrier function will be tested based on preliminary data demonstrating a greater barrier to water loss in blacks compared to whites. The ability of maternal glucocorticoid administration to accelerate epidermal barrier maturation and, conversely, the effect of amnionitis/meconium exposure to impair the barrier will be examined. Clinical studies in preterm infants will be performed using a unique, computerized temperature control and data acquisition system specifically designed for temperature regulation in preterm infants. The rapid falloff in epidermal barrier function prior to 30 weeks gestation and the accelerated postnatal maturation of the barrier following preterm birth will be utilized to score gestational (skin) age. This objective bedside nursing assessment of epidermal integrity will be combined with the new Ballard score and compared with other measures such as the Best Obstetrical Estimate as a predictor of neonatal mortality, morbidity, and cost. It is hypothesized that reliable, noninvasive bedside monitoring of epidermal barrier function will lead to optimization of nursing care, improved patient outcome, and earlier discharge in hospitalized preterm human infants.