ASSOCIATION BETWEEN SKIN BARRIER DEVELOPMENT AND EARLY-ONSET ATOPIC DERMATITIS: A LONGITUDINAL BIRTH COHORT STUDY

A diagnosis of atopic dermatitis (AD) is common during infancy; however, it is unclear whether differential skin barrier development defines this period and signals disease onset in predisposed individuals. A longitudinal observational cohort study (NCT03143504) assessed the feasibility of remote skin testing from birth to monitor skin barrier maturation and model association with an AD diagnosis by 12-months of age. Biophysical testing and infrared spectroscopy were conducted at the maternity ward and family home. Tape stripping collected samples for desquamatory protease and Natural Moisturising factor (NMF) analysis. The four common European Filaggrin (FLG) risk alleles were screened. A total of 128 infants completed the study with 20% developing mild disease. Significant changes in permeability barrier function, desquamatory protease activity and molecular composition assessed spectroscopically were observed longitudinally, but only subtle evidence of differential skin barrier development was noted between infant subgroups. Common FLG risk alleles were strongly associated with early onset disease and conferred a significant reduction in NMF and water content by four weeks of age. Accounting for a family history of atopy, these parameters alongside a greater lipid/protein ratio and reduced chymotrypsin-like activity at birth were associated with AD. Measured in ambient conditions, transepidermal water loss did not signal disease risk at any stage. Skin barrier dysfunction lacked an acquired modality but was considered proportional to cohort severity and suggests that a portfolio of tests used in a community setting, has the potential to improve current AD risk evaluations from birth

Initial phases of massive star formation in high infrared extinction clouds. I. Physical parameters

The earliest phases of massive star formation are found in cold and dense infrared dark clouds (IRDCs). Since the detection method of IRDCs is very sensitive to the local properties of the background emission, we present here an alternative method to search for high column density in the Galactic plane by using infrared extinction maps. We find clouds between 1 and 5 kpc, of which many were missed by previous surveys. By studying the physical conditions of a subsample of these clouds, we aim at a better understanding of the initial conditions of massive star formation. We made extinction maps of the Galactic plane based on the 3.6-4.5 microns color excess between the two shortest wavelength Spitzer IRAC bands, reaching to visual extinctions of ~100 mag and column densities of 9x10^22 cm^-2. From this we compiled a new sample of cold and compact high extinction clouds. We used the MAMBO array at the IRAM 30m telescope to study the morphology, masses and densities of the clouds and the dense clumps within them. The latter were followed up by pointed ammonia observations with the 100m Effelsberg telescope, to determine rotational temperatures and kinematic distances. Extinction maps of the Galactic plane trace large scale structures such as the spiral arms. The 1.2 mm emission maps reveal that the high extinction clouds contain extended cold dust emission, from filamentary structures to still diffuse clouds. Most of the clouds are dark in 24 microns, but several show already signs of star formation via maser emission or bright infrared sources, suggesting that the high extinction clouds contain a variety of evolutionary stages. The observations suggest an evolutionary scheme from dark, cold and diffuse clouds, to clouds with a stronger 1.2 mm peak and to finally clouds with many strong 1.2 mm peaks, which are also warmer, more turbulent and already have some star formation signposts.Comment: 26 pages, 14 figures, 9 tables. Accepted for publication in Astronomy and Astrophysics, small corrections implemente

Vitamin D and antimicrobial peptide levels in patients with atopic dermatitis and atopic dermatitis complicated by eczema herpeticum: A pilot study.

In this study, Vitamin D supplementation results in improved clinical severity of atopic dermatitis and increased skin surface LL-37 levels, analyzed by a novel, non-invasive method. Vitamin D supplementation could be a therapeutic option in AD

Rotation, activity, and lithium abundance in cool binary stars

We have used two robotic telescopes to obtain time-series high-resolution spectroscopy and V I and/or by photometry for a sample of 60 active stars. Orbital solutions are presented for 26 SB2 and 19 SB1 systems with unprecedented phase coverage and accuracy. The total of 6,609 R=55,000 echelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute H{\alpha}-core fluxes as a function of time. The photometry is used to infer unspotted brightness, V - I and/or b - y colors, spot-induced brightness amplitudes and precise rotation periods. Our data are complemented by literature data and are used to determine rotation-temperature-activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74% of all known rapidly-rotating active binary stars are synchronized and in circular orbits but 26% are rotating asynchronously of which half have Prot > Porb and e > 0. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin-down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars. For inactive, single giants with Prot > 100 d, the relation is much weaker. Our data also indicate a period-activity relation for H{\alpha} of the form RH{\alpha} \propto P - 0.24 for binaries and RH{\alpha} \propto P -0.14 for singles. Lithium abundances in our sample increase with effective temperature. On average, binaries of comparable effective temperature appear to exhibit 0.25 dex less surface lithium than singles. We also find a trend of increased Li abundance with rotational period of form log n(Li) \propto - 0.6 log Prot

The Effect of Water Hardness on Surfactant Deposition after Washing and Subsequent Skin Irritation in Atopic Dermatitis Patients and Healthy Control Subjects

Living in a hard water area is associated with an increased risk of atopic dermatitis (AD). Greater skin barrier impairment after exposure to surfactants in wash products, combined with the high calcium levels of hard water and/or high chlorine levels, is a compelling mechanism for this increase. The purpose of this study was to investigate this mechanism in individuals with and without a predisposition to skin barrier impairment. We recruited 80 participants: healthy control subjects and AD patients with and without FLG mutations. The skin of each participant was washed with sodium lauryl sulfate in water of varying hardness levels and chlorine concentrations, rinsed, and covered with chambers to determine the effects of surfactant residues. Sites washed with hard water had significantly increased sodium lauryl sulfate deposits. These deposits increased transepidermal water loss and caused irritation, particularly in AD patients carrying FLG mutations. A clear effect of chlorine was not observed. Water softening by ion-exchange mitigated the negative effects of hard water. Barrier impairment resulting from the interaction between hard water and surfactants is a contributory factor to the development of AD. Installation of a water softener in early life may be able to prevent AD development. An intervention study is required to test this hypothesis

Expression of the multi-drug efflux genes acrAB of 'Escherichia coli'

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Expression of the multi-drug efflux genes acrAB of Escherichia coli

The action of AcrAB-ToIC, a multidrug efflux system of Escherichia co/i, is largely responsible for the increased intrinsic resistance of this organism to many antimicrobial agents. The level of mRNA specific to the acrAB efflux genes is elevated by six-fold during exponential phase of growth in LB broth. In MOPS minimal medium supplemented with 0.4 % (w/v) glucose, levels of acrA mRNA remain higher for a prolonged period of time concurrent with the delayed onset of stationary phase, suggesting that transcription of this gene is linked with active growth. A case for transcriptional activation of this gene by RNA polymerase associated with the "housekeeping" sigma factor, a 7o, is presented. Investigation of acrAB transcription in E. co/i SD1648 using the acrAB::lacZ reporter system encoded on a plasmid (pNN602) appears to contradict these fmdings, suggesting that acrAB transcription is induced upon entry into stationary phase. This paradox is attributed to fundamental differences between the two methods of investigating transcription, and suggests that acrAB expression is subject to post-transcriptional regulation or that the plasmid based reporter system fails to convey an important aspect of control. Notably acrA niRNA levels suggest transient induction of acrA transcription upon transition into stationary phase of growth; however this is secondary to the observed exponential phase peak in transcript levels. In addition to the general stress conditions already found to induce acrAB transcription including 0.4 % (v/v) ethanol and 0.5 M sodium chloride, bile salts (cholate and deoxycholate), ampicillin, and growth on certain carbon sources, were found to induce acrAB transcription. A family of isogenic mutant strains based on the lacZ derivative of E. co/i MG1655 (SD 1648) harbouring specific gene disruptions was constructed in order to investigate the effect of key regulatory factors on transcription of the acrAB genes. CRP-cAMP, FIS, H-NS, Rob, AcrR, OmpRJEnvZ, CsrAB, and SdiA were all found to have significant effects on acrAB transcription. A real-time reverse transcription-polymerase chain reaction (RT-PCR) assay, using the Roche LightCyclerTM Instrument, was developed for the purpose of this investigation of acrA gene transcription. The assay was used specifically to quantify acrA mRNA levels; however the method can readily be applied to the study of other E. coli genes. The method was uniquely applied to the investigation of acrAB transcription throughout the growth cycle of E. co/i during batch culture in LB broth, in order to ascertain the patterns of expression for this gene. Following this, the RT-PCR assay was used as a novel approach to determining the start of transcription for the acrAB genes. Where transcription is initiated from more than one promoter, this method could be applied further to determine the relative strengths of each promoter, in vivo, under different conditions. In the case of the acrAB genes a promoter was located between 224 and 383 bases upstream from the acrA start of translation. This suggests that at least two promoters exist upstream of the acrAB genes, the implications of which are discussed

Use of oil for baby skincare: A survey of UK maternity and neonatal units

Olive oil is commonly recommended by health professionals to new parents for use in the prevention and treatment of the term baby's dry skin, and for baby massage. There is no evidence to support this practice. The use of olive oil may be harmful to skin, affecting skin barrier function. This effect may be a contributory factor in the prevalence of childhood conditions such as atopic eczema. This paper discusses a national online audit of UK maternity hospitals (n = 67) and neonatal units (n = 33) performed between November 2010 and January 2011. Our findings confirm that oil use on babies' skin is common practice. As the direct cost to the NHS for treatment of atopic eczema is high, it is imperative that further research in this area is performed, preferably in the form of a randomized controlled trial. Health professionals will then be in a position to provide accurate information to parents with regard to oil in baby skin care regimens. </jats:p