Characterisation of skin barrier defects in atopic dermatitis patients using Infrared Spectroscopy.

INTRODUCTION: Atopic dermatitis (AD) is characterised by skin barrier defects often measured by biophysical tools that observe stratum corneum (SC) functional properties. OBJECTIVE: To employ in vivo infrared spectroscopy alongside biophysical measurements to analyse changes in chemical composition of the SC in relation to AD severity. METHODS: We conducted an observational cross-sectional cohort study where attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy measurements were collected on the forearm alongside surface pH, capacitance, erythema and transepidermal water loss (TEWL) combined with tape stripping (STS) in a cohort of 75 participants; 55 AD patients stratified by phenotypic severity, compared to 20 healthy controls. Common filaggrin (FLG) variant alleles were genotyped. RESULTS: Reduced hydration, elevated TEWL and redness all associated with greater AD severity. Spectral analysis showed a reduction in 1465cm-1 (full width half maximum) and 1340 cm-1 peak areas indicative of less orthorhombic lipid ordering and reduced carboxylate functional groups that correlated with clinical severity (lipid structure r=-0.59, carboxylate peak area r=-0.50). CONCLUSION: ATR-FTIR spectroscopy is a suitable tool for the characterisation of structural skin barrier defects in AD and has potential as a clinical tool for directing individual treatments based on chemical structural deficiencies.

Enhancement of stratum corneum lipid structure improves skin barrier function and protects against irritation in adults with dry, eczema-prone skin.

BACKGROUND: The skin of patients with atopic dermatitis is characterized by abnormal stratum corneum lipid levels. Consequently, the lamellar matrices are disrupted and skin barrier function is diminished, increasing skin sensitivity to irritants and allergens. OBJECTIVES: To determine whether a cream containing ceramides, triglycerides and cholesterol in a multivesicular emulsion can reinforce the skin barrier and protect against skin irritation. METHODS: A randomized observer-blind intrapatient-controlled study in 34 adults with dry, eczema-prone skin was conducted. Each participant underwent 4 weeks of treatment with the test cream on one forearm and lower leg and a reference emollient cream on the other. Skin properties were determined before and after treatment. Lipid structure was assessed by Fourier-transform infrared spectroscopy using a novel interface. RESULTS: Skin barrier integrity was greater at sites treated with the test cream [effect size for area under the transepidermal water loss curve -162, 95% confidence interval (CI) -206 to -118]. Skin sensitivity to sodium lauryl sulfate was reduced (-0·5 points visual redness, 97·57% CI -1·00 to -0·25), as was transepidermal water loss (-15·3 g m-2 h-1 , 95% CI -20·3 to -10·4) compared with the reference. Sites treated with the test cream displayed enhanced lipid chain ordering, which was significantly associated with skin barrier integrity (r = 0·61). Compared with the reference, treatment with the test cream increased hydration (8·61 capacitance units, 95% CI 6·61-10·6) and decreased signs of dryness. CONCLUSIONS: The test cream facilitates skin barrier restoration and protects the skin from dryness and irritation. Compared with a commonly prescribed emollient in the UK, the test cream is highly suited to the management of dry, sensitive skin.

Detection & identification of hazardous narcotics and new psychoactive substances using Fourier transform infrared spectroscopy (FTIR).

According to the latest World Drug Report, released by the United Nations Office on Drugs and Crime (UNODC), drug use is up 30% over the past decade and there are more drugs, and more types of drugs, than ever. Herein we use Fourier Transform Infrared Spectroscopy (FTIR) for the rapid ID of narcotics in a range of concentrations - from pure forms (as it is likely to be smuggled & transported) to street forms, often mixed with conventional cutting agents. Using FTIR, 75% of "street sample" narcotics were rapidly identified, and the effects of cutting agents on identification (ID) were also investigated. The limit of detection of MDMA was assessed, with a correct ID shown from 25% w/v. Concentration was correlated with Hit Quality Index, showing the capability of FTIR use in concentration estimation.

Gelatin-containing porous polycaprolactone PolyHIPEs as substrates for 3D breast cancer cell culture and vascular infiltration.

Tumour survival and growth are reliant on angiogenesis, the formation of new blood vessels, to facilitate nutrient and waste exchange and, importantly, provide a route for metastasis from a primary to a secondary site. Whilst current models can ensure the transport and exchange of nutrients and waste via diffusion over distances greater than 200 µm, many lack sufficient vasculature capable of recapitulating the tumour microenvironment and, thus, metastasis. In this study, we utilise gelatin-containing polymerised high internal phase emulsion (polyHIPE) templated polycaprolactone-methacrylate (PCL-M) scaffolds to fabricate a composite material to support the 3D culture of MDA-MB-231 breast cancer cells and vascular ingrowth. Firstly, we investigated the effect of gelatin within the scaffolds on the mechanical and chemical properties using compression testing and FTIR spectroscopy, respectively. Initial in vitro assessment of cell metabolic activity and vascular endothelial growth factor expression demonstrated that gelatin-containing PCL-M polyHIPEs are capable of supporting 3D breast cancer cell growth. We then utilised the chick chorioallantoic membrane (CAM) assay to assess the angiogenic potential of cell-seeded gelatin-containing PCL-M polyHIPEs, and vascular ingrowth within cell-seeded, surfactant and gelatin-containing scaffolds was investigated via histological staining. Overall, our study proposes a promising composite material to fabricate a substrate to support the 3D culture of cancer cells and vascular ingrowth.