Janeta Nikolovski

Barrier Function and Water-Holding and Transport Properties of Infant Stratum Corneum Are Different from Adult and Continue to Develop through the First Year of Life

Skin water barrier development begins in utero and is believed to be complete by week 34 of gestational age. The goal of this investigation was to assess the dynamic transport and distribution of water of the stratum corneum of infants and compare it to those of adults. The interaction of water with the stratum corneum was assessed by measuring capacitance, transepidermal water loss (TEWL), rates of absorption-desorption as well as Raman spectra as a function of depth (a total of 124 infants (3-12 months) and 104 adults (14-73 years)). The results show that capacitance, TEWL, and absorption-desorption rates had larger values consistently for infant stratum corneum throughout the first year of life and showed greater variation than those of adults. The Raman spectra analyzed for water and for the components of natural moisturizing factor (NMF) showed the distribution of water to be higher and have a steeper gradient in infants than in adults; the concentration of NMF was significantly lower in infants. The results suggest that although the stratum corneum of infants may appear intact shortly after birth (<1 month), the way it stores and transports water becomes adult-like only after the first year of life.

Diversity of the Human Skin Microbiome Early in Life

Within days after birth, rapid surface colonization of infant skin coincides with significant functional changes. Gradual maturation of skin function, structure, and composition continues throughout the first years of life. Recent reports have revealed topographical and temporal variations in the adult skin microbiome. Here we address the question of how the human skin microbiome develops early in life. We show that the composition of cutaneous microbial communities evolves over the first year of life, showing increasing diversity with age. Although early colonization is dominated by Staphylococci, their significant decline contributes to increased population evenness by the end of the first year. Similar to what has been shown in adults, the composition of infant skin microflora appears to be site specific. In contrast to adults, we find that Firmicutes predominate on infant skin. Timely and proper establishment of healthy skin microbiome during this early period might have a pivotal role in denying access to potentially infectious microbes and could affect microbiome composition and stability extending into adulthood. Bacterial communities contribute to the establishment of cutaneous homeostasis and modulate inflammatory responses. Early microbial colonization is therefore expected to critically affect the development of the skin immune function.

Infant skin microstructure assessed in vivo differs from adult skin in organization and at the cellular level.

Abstract:  Functional differences between infant and adult skin may be attributed to putative differences in skin microstructure. The purpose of this study was to examine infant skin microstructure in vivo and to compare it with that of adult skin. The lower thigh area of 20 healthy mothers (ages 25–43) and their biological children (ages 3–24 months) was examined using in vivo noninvasive methods including fluorescence spectroscopy, video microscopy, and confocal laser scanning microscopy. Stratum corneum and supra‐papillary epidermal thickness as well as cell size in the granular layer were assessed from the confocal images. Adhesive tapes were used to remove corneocytes from the outer‐most layer of stratum corneum and their size was computed using image analysis. Surface features showed differences in glyph density and surface area. Infant stratum corneum was found to be 30% and infant epidermis 20% thinner than in adults. Infant corneocytes were found to be 20% and granular cells 10% smaller than adult corneocytes indicating a more rapid cell turnover in infants. This observation was confirmed by fluorescence spectroscopy. Dermal papillae density and size distribution also differed. Surprisingly, a distinct direct structural relationship between the stratum corneum morphology and the dermal papillae was observed exclusively in infant skin. A change in reflected signal intensity at ∼100 μm indicating the transition between papillary and reticular dermis was evident only in adult skin. We demonstrate in vivo qualitative and quantitative differences in morphology between infant and adult skin. These differences in skin microstructure may help explain some of the reported functional differences.

Infant skin physiology and development during the first years of life: a review of recent findings based on in vivo studies

Infant skin is often presented as the cosmetic ideal for adults. However, compared to adult skin it seems to be more prone to develop certain pathological conditions, such as atopic dermatitis and irritant contact dermatitis. Therefore, understanding the physiology of healthy infant skin as a point of reference is of interest both from the cosmetic as well as from the clinical point of view. Clinical research on healthy infants is, however, limited because of ethical considerations of using invasive methods and therefore until recently data has been scarce. Technical innovations and the availability of non‐invasive in vivo techniques, such as evaporimetry, electrical impedance measurement, in vivo video and confocal microscopy, and in vivo fibre‐optic based spectroscopy, opened up the field of in vivo infant skin physiology research. Studies incorporating such methods have demonstrated that compared to adult, infant skin continues to develop during the first years of life. Specifically, infant skin appears to have thinner epidermis and stratum corneum (SC) as well as smaller corneocytes at least until the second year of life. The water‐handling properties are not fully developed before the end of the first year and infant SC contains more water and less amounts of natural moisturizing factors. Such findings re‐evaluate the old notions that skin is fully matured at birth. Armed with this knowledge, we are in a position not only to better understand infant dermatological conditions but also to design better skin care products respecting the distinct qualities of infant skin.

Sleep patterns and sleep disturbances across pregnancy

OBJECTIVE This study sought to characterize sleep patterns and sleep problems in a large sample of women across all months of pregnancy. METHODS A total of 2427 women completed an Internet-based survey that included the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, vitality scale of the Short Form 36 Health Survey (SF-36), Insomnia Severity Index (ISI), Berlin questionnaire, International Restless Legs Syndrome (IRLS) question set, and a short version of the Pregnancy Symptoms Inventory (PSI). RESULTS Across all months of pregnancy, women experienced poor sleep quality (76%), insufficient nighttime sleep (38%), and significant daytime sleepiness (49%). All women reported frequent nighttime awakenings (100%), and most women took daytime naps (78%). Symptoms of insomnia (57%), sleep-disordered breathing (19%), and restless legs syndrome (24%) were commonly endorsed, with no difference across the month of pregnancy for insomnia, sleep-disorder breathing, daytime sleepiness, or fatigue. In addition, high rates of pregnancy-related symptoms were found to disturb sleep, especially frequent urination (83%) and difficulty finding a comfortable sleep position (79%). CONCLUSIONS Women experience significant sleep disruption, inadequate sleep, and high rates of symptoms of sleep disorder throughout pregnancy. These results suggest that all women should be screened and treated for sleep disturbances throughout pregnancy, especially given the impact of inadequate sleep and sleep disorders on fetal, pregnancy, and postpartum outcomes.

Impact of a group mind/body intervention on pregnancy rates in IVF patients

OBJECTIVE To determine if women who were randomized to a mind/body program before starting their first IVF cycle would have higher pregnancy rates than control subjects. DESIGN Randomized, controlled, prospective study. SETTING Private academically affiliated infertility center. PATIENT(S) A total of 143 women aged≤40 years who were about to begin their first IVF cycle. INTERVENTION(S) Subjects were randomized to a ten-session mind/body program (MB) or a control group and followed for two IVF cycles. MAIN OUTCOME MEASURE(S) Clinical pregnancy rate. RESULT(S) Only 9% of the MB participants had attended at least one-half of their sessions at cycle 1 start. Pregnancy rates for cycle 1 were 43% for all subjects; 76% of the MB subjects had attended at least one-half of their sessions at cycle 2 start. Pregnancy rates for cycle 2 were 52% for MB and 20% for control. CONCLUSION(S) MB participation was associated with increased pregnancy rates for cycle 2, prior to which most subjects had attended at least half of their sessions.