The revised EEMCO guidance for the in vivo measurement of water in the skin

Skin hydration and transepidermal water loss after bathing compared between immersion and showering

BACKGROUND

Various methods of bathing may affect skin properties differently.

AIMS

To compare the effects of immersion and showering on skin hydration and transepidermal water loss (TEWL).

METHOD

This experimental study included healthy volunteers whose forearms were immersed and showered for 3 minutes. Skin hydration and TEWL were assessed serially before and after immersion and showering of volunteer forearms.

RESULTS

Seventy-eight healthy volunteers (49 females, 29 males) were enrolled with an age range of 12-55 years (mean 31.41 ± 10.33). Both methods significantly increased skin hydration and TEWL (P < .001). The capacitance value significantly increased immediately after bathing, and then rapidly decreased within 3 minutes. It returned to baseline by 10 minutes after bathing. There was no statistically significant difference of capacitance between the two methods at any measurement (P > .05). TEWL at every measurement after bathing was significantly increased compared to baseline for both bathing methods (P < .001). The highest TEWL was observed immediately after bathing, but then significantly decreased compared to the previous measurement (P < .001).

CONCLUSION

Immersion and showering similarly demonstrated significant increase in skin hydration and TEWL. The increment of capacitance after bathing returned to baseline level within 10 minutes.

Multi parametric biophysical assessment of treatment effects on xerotic skin

Background

Topical moisturizing products are widely used to alleviate the problems associated with xerotic skin. Their use affects many properties of the stratum corneum (SC) in a complex and interrelated manner. The range of measurement techniques available to the researcher has increased in recent years. However, few studies have looked for correlations between the different techniques for assessing how aspects of xerotic skin change over time as a result of topical moisturizer usage.

Objectives

A 3‐week in vivo study using an oil‐in‐water based moisturizing product and an untreated site was conducted to determine the clinical significance of and any correlations between a range of different approaches for the measurement of skin lipid content and also skin hydration and visual grading of dry skin.

Methods

A range of traditional and more recently developed skin measurement techniques have been used to examine a variety of SC properties in normal and xerotic skin during topical moisturizer usage.

Results

In vivo confocal Raman spectroscopy and analysis of SC lipids from tape strips both showed an increase in SC lipid level and organization after 3 weeks of moisturizer usage on xerotic skin. Hydration, measured both optically and electrically, also increased and skin barrier function improved, with strong correlations between the different measures of dryness being observed.

Conclusions

Strong correlations were observed between the skin measurements for lipid assessment and skin hydration with regard to the assessment of xerotic skin, providing valuable new information for future in vivo clinical research into dry and atopic skin.

Keywords

biophysical assessment, skin barrier, skin hydration, topical moisturizers, Xerosis

Design and Analysis of a Continuous and Non-Invasive Multi-Wavelength Optical Sensor for Measurement of Dermal Water Content

Dermal water content is an important biophysical parameter in preserving skin integrity and preventing skin damage. Traditional electrical-based and open-chamber evaporimeters have several well-known limitations. In particular, such devices are costly, sizeable, and only provide arbitrary outputs. They also do not permit continuous and non-invasive monitoring of dermal water content, which can be beneficial for various consumer, clinical, and cosmetic purposes. We report here on the design and development of a digital multi-wavelength optical sensor that performs continuous and non-invasive measurement of dermal water content. In silico investigation on porcine skin was carried out using the Monte Carlo modeling strategy to evaluate the feasibility and characterize the sensor. Subsequently, an in vitro experiment was carried out to evaluate the performance of the sensor and benchmark its accuracy against a high-end, broad band spectrophotometer. Reference measurements were made against gravimetric analysis. The results demonstrate that the developed sensor can deliver accurate, continuous, and non-invasive measurement of skin hydration through measurement of dermal water content. Remarkably, the novel design of the sensor exceeded the performance of the high-end spectrophotometer due to the important denoising effects of temporal averaging. The authors believe, in addition to wellbeing and skin health monitoring, the designed sensor can particularly facilitate disease management in patients presenting diabetes mellitus, hypothyroidism, malnutrition, and atopic dermatitis.

The association between activity levels and skin moisturising function in adults

Factors associated with skin moisture retention include age and lifestyle, such as diet and sleep efficiency. However, the impact of exercise habits on skin moisturising function is unclear. We surveyed 86 participants from a Japanese university about their activity levels using the International Physical Activity Questionnaire. We also examined their skin moisturising function, measuring stratum corneum (SC) hydration levels and transepidermal water loss (TEWL). Comparisons of participants’ activity levels, SC hydration, and TEWL, accounting for their gender and age differences, revealed activity levels significantly related to differences in SC hydration levels. Results of multiple comparisons showed increased activity relates to significantly higher SC hydration − the higher the activity levels, the higher the hydration. No difference was found in TEWL. The results suggest exercise habits can prevent dry skin. The findings may be useful for the prevention and treatment of dry skin and promoting the benefits of exercise.

Non-invasive assessment of urea efficacy: A review

Urea is an emollient widely used in clinical dermatology to moisturise and protect the skin. Non-invasive techniques can be useful in evaluating and quantifying the moisturising and hydrating properties of topically applied urea. Amongst these, transepidermal water loss, skin conductance and capacitance are the most widely used. Dynamic tests and mapping of skin moisturisation are additional features that can be used to evaluate the dynamics of water into the stratum corneum. Ultrasound and mechanical properties can be used to investigate the effects on skin smoothness and tone. In conclusion, urea is a fundamental ingredient of cosmetic and dermatological formulations and can have several positive effects on skin function. These can be easily investigated and monitored using non-invasive techniques measuring the stratum corneum function.

Skin Impedance Measurements with Nanomesh Electrodes for Monitoring Skin Hydration

The importance of continuous monitoring of skin hydration in daily life, to aid in the diagnosis of skin diseases, is rising. Electrodes that can be worn directly on the skin are attracting attention as an effective means. However, they should not inhibit natural water evaporation from the skin and should not cause inflammation or irritation even if they are attached to the body for long periods of time. In this study, nanomesh electrodes that have previously been reported to exhibit high biocompatibility are also found to exhibit high water vapor permeability, resulting in properties that prevent skin dampness. Furthermore, the skin impedance measured using nanomesh electrodes is found to correlate with the hydration level of skin measured using existing medical equipment. This study provides a new approach to measure skin hydration in conditions close to bare skin.

Functional recovery in human partial thickness skin wounds after application of multicomponent hydrolipidic film (MAS063DP): A prospective, open-label, comparative clinical trial

Acute and minor skin wounds are common in daily life. However, in clinical practice, after initial management in the acute phase, the wounds are managed mainly through observation, and the patients are usually lost to follow-up. Considering a multicomponent hydrolipidic dressing (MAS063DP) long-known for its safe application in eczema and recently in laser-induced wounds, we aimed to evaluate its ability in functional recovery of impaired skin integrity during wound healing. Sixteen patients (N = 16) were enrolled and completed (n = 8 vs n = 8) this prospective, open-label, vehicle-controlled clinical trial with 12-week follow-up. Transepidermal water, skin viscoelasticity and bioimpedance analysis were measured initially, at the 1st, 4th, 8th, and 12th weeks. Improvements in these parameters were greater in the MAS063DP group (from 31.4 ± 9.0 to 16.4 ± 4.3 g/m² h, P < .001; from 77 ± 16% to 88 ± 9%, P < .05; from 4182 ± 3823 to 2644 ± 1772 Ω) than in the white petrolatum group. No significant adverse events occurred, and all participants were more satisfied with the intervention. In this study, MAS063DP can restore skin integrity and reinstitute physiologic function as a feasible and safe intervention more markedly than management through observation during the healing process by providing protective hydrolipidic layer on the skin with simultaneous anti-inflammatory and antioxidant activities from its key ingredients such as glycyrrhetinic acid, Vitis vinifera, telmesteine, and vitamins C and E.

The influence of topical 5% tranexamic acid at pH 2.38 with and without corundum microdermabrasion on pigmentation and skin surface lipids

Tranexamic acid (TA) has anti-hemorrhagic effects; however, oral administration has been found to decrease hyperpigmentation. The aim of the work was to compare the effects of treatment with 5% tranexamic acid in combination with corundum microdermabrasion on skin pigmentation, redness, pH, transepidermal water loss (TEWL), sebum level and hydration of back surface and dorsal surface of the hand skin. Six treatments were performed every week on the back surface and both dorsal surfaces of the hands of 12 subjects. The entire back/both hands were treated with 5% tranexamic acid at pH 2.38; left side of the back or left hand were also subjected to corundum microdermabrasion. Skin parameters were measured using the Courage & Khazaka 580 Multi Probe Adapter. Clinical photos were taken using the Fotomedicus system. Significant differences between treatment methods were observed for melanin, erythema and pH. In addition, the two methods differed significantly with regard to the amount of sebum, TEWL and the level of moisture in the skin. Both methods gave similar acidic pH. Summing up tranexamic acid causes a significant reduction in epidermal melanogenesis, has a significant impact on the level of skin hydration, lipids of the epidermis and maintaining the proper TEWL. TA has a significant effect on reducing skin redness.

Comparison of mechanical, chemical and physical human models of in vivo skin damage: Randomized controlled trial

INTRODUCTION

Human in vivo models of skin damage were often used in research of cutaneous disorders. The most commonly used models were tape-stripping as mechanical, sodium lauryl sulphate-induced irritation as chemical and ultraviolet radiation as physical damage model. In regard to differences between models, they were expected to have different responses to damage and recovery, with unique skin parameters' changes over time.

OBJECTIVE

The aim was to compare skin parameters in three different skin damage models on the same anatomical location, with and without topical treatment.

METHODS

Four test sites on each forearm were randomly assigned to three skin damage models with the fourth sites on each forearm chosen as a control, undamaged site. Skin parameters were assessed using non-invasive methods.

RESULTS

Sodium lauryl sulphate irritation caused the strongest damage with delayed reaction to the irritant. Tape stripping leads to highest initial skin barrier disruption but afterwards it showed the fastest skin recovery. Ultraviolet radiation did not affect skin barrier function, but it elevated skin erythema and melanin level. Tested preparation did not lead to changes in measured parameters.

CONCLUSION

The skin of the participants had different response to three skin damage models with distinct changes of skin parameters and recovery. The trial was registered at ClinicalTrials.gov under the identifier NCT03783819.

Aloe barbadensis: A Plant of Nutricosmetic Interest

Aloe barbadensis Miller (Aloe Vera Linne) products have long been employed in health foods and for medical purposes. It has anti-inflammatory, antifungal, antioxidant properties, which indicates excellent potential in antiaging cosmetic and skin protection products. The objective of this study is to evaluate the antiaging efficacy of dermocosmetic formulations containing A. barbadensis extract on young and mature skin using biophysical and skin imaging techniques. Twenty healthy adult volunteers participated in the study, aged between 20 and 65. The cream formulation, with 10% (w/w) of A. barbadensis extract, and placebo, were applied to the face of the volunteers. The effects were evaluated in terms of skin hydration and barrier effect by the measurement of transepidermal water loss (TEWL), derma firmness, and elasticity. The formulation containing A. barbadensis extract significantly improves water contained in the stratum corneum, firmness, elasticity of the skin, and decreased TEWL.

Changes in facial moisture distribution and feelings of moisture/dryness among various environmental temperatures and humidities in summer and winter

BACKGROUND

As environmental conditions vary depending on area of residence, consideration of environmental temperature and humidity conditions is crucial for detection of actual skin conditions in daily life. In this study, we determined changes in facial moisture and sensory evaluation distributions in various environmental temperature and humidity conditions.

MATERIALS AND METHODS

An original near-infrared (NIR) imaging system was used to obtain moisture distributions. Sensory evaluations of feelings of moisture/dryness were graded, and changes were compared among 10 healthy Japanese female subjects in four different environmental temperature and humidity conditions (28°C, 60% RH; 28°C, 20% RH; 15°C, 60% RH; 15°C, 20% RH) in summer and winter.

RESULTS

Skin moisture was lower at high temperatures and higher at low temperatures. Feelings of dryness on bare skin were high in low humidity. Sensitivity of feelings of moisture and dryness was high around the center of the cheekbones between side of the eyes and the mouth, but the same was not true of the moisture distribution. Moisture level was lower in winter at high temperatures, especially under the eyes near the side of the nose ridge, while the sense of dryness was not strong. These divergences between sensory evaluation and moisture level indicate the presence of a "hidden dry situation."

CONCLUSION

Changes in moisture level and sensory evaluation scores in facial skin varied among environmental conditions, which differed between summer and winter, even under the same environmental temperature and humidity.

Value of GPSkin for the measurement of skin barrier impairment and for monitoring of rosacea treatment in daily practice

Background

Stratum corneum hydration (SCH) and transepidermal water loss (TEWL) provide useful information about skin barrier function. This study aimed to determine the value of GPSkin Pro, a new handheld device determining both SCH and TEWL, to measure skin barrier impairment and to monitor barrier function in rosacea in daily practice.

Materials and Methods

Two pilots were performed. Pilot 1: in 27 healthy participants, GPSkin SCH and TEWL were compared to Aquaflux^® and Epsilon^® values at the forearm before and after skin barrier perturbation via tapestripping. Moreover, GPSkin values were measured at both cheeks without intervention. Pilot 2: in 16 rosacea patients, GPSkin measurements were performed at the forearm, and at both cheeks before and during anti‐inflammatory treatment. They were compared to clinical symptoms and to GPSkin values from pilot 1.

Results

Pilot 1: after merging data from before and after tapestripping, a strong correlation was observed between GPSkin TEWL and Aquaflux^® (R_s = 0.9256), and GPSkin SCH and Epsilon^® (R_s = 0.8798). Pilot 2: SCH was significantly lower at the cheeks of rosacea patients compared to controls, with a normalizing trend during successful treatment. TEWL was comparable among patients and controls and did not change during treatment at all locations.

Conclusion

The GPSkin determines TEWL and SCH accurately in healthy and impaired skin barrier state and can monitor skin barrier function in rosacea during treatment. The GPSkin device is much more practical compared to previous skin barrier tools when used in clinical practice. Its further validation in other inflammatory skin diseases is recommended.

Skin barrier function in patients under radiation therapy due to the head and neck cancers - Preliminary study

Aim

To present the possibility of non-invasive monitoring of the skin after radiotherapy in regards of epidermal barrier function.

Background

Radiodermatitis constitutes 95% of all side effects in patients after radiotherapy. The proper assessment of the severity of radiodermatitis can be determined using semi-quantitative clinical scores [Common Terminology Criteria for Adverse Events v 4.0 (CTCAE)].The most accepted way to analyze the epidermal barrier function is to determine Transepidermal Water Loss (TEWL).

Material and methods

In prospective study, we included 16 patients diagnosed with head and neck cancer treated with radiotherapy or concomitant chemoradiation in whom we performed non-invasive assessments of the skin barrier function, including TEWL measurement. The final analysis included 6 patients (4 treated with adjuvant radiotherapy, 2 with radical chemoradiation). Clinical assessment of irradiated skin was based on target lesion score (TLS) and CTCAE v 4.0.

Results

The mean TLS score in the middle of irradiation was 1.6 points, after last irradiation it was 2.3 points; 3 months later the mean TLS score was: 0. CTCAE v 4.0 criteria: 2 patients had grade 0, 3 patients - grade 1; 1 patient - grade 2. There were statistically significant differences in TEWL related to irradiated skin in the following time intervals: before vs. in the middle; before vs. day after; in the middle vs. day after; in the middle vs. 3 months after; day after vs. 3 months after.

Conclusions

The study showed that radiotherapy causes skin barrier dysfunction in all patients independently of clinical radiodermatitis. The biophysical features of this dysfunction can precede clinical symptoms and they can be assessed by non-invasive and objective methods.

Evaluation of the Filming and Protective Properties of a New Trehalose and Ceramides Based Ingredient

The aim of this study is showing the filming and skin barrier protective properties of a new ingredient based on ceramides and trehalose and carried in lipophilic vesicles composed of lecithin and cholesterol (or phytosterols). Through an in vivo study, the restructuring and hydrating properties of this trehalose and ceramides compound have been evaluated. Furthermore, this new ingredient has been used in a topical formulation for atopic dermatitis, proving to be effective in the alterations of skin barrier. This evidence makes it an interesting ingredient for topical dermatological compositions in the treatment of dermatitis and all manifestations correlated to these skin disorders, such as edema, swelling, rash, redness, and itching. Its soothing and protective action against the painful and annoying symptoms like those given by dermatitis makes this trehalose and ceramides based ingredient for topical use.

Recent Advances in Skin Chemical Sensors

This review summarizes the latest developments in the field of skin chemical sensors, in particular wearable ones. Five major applications are covered in the present work: (i) sweat analysis, (ii) skin hydration, (iii) skin wounds, (iv) perspiration of volatile organic compounds, and (v) general skin conditions. For each application, the detection of the most relevant analytes is described in terms of transduction principles and sensor performances. Special attention is paid to the biological fluid collection and storage and devices are also analyzed in terms of reusability and lifetime. This review highlights the existing gaps between current performances and those needed to promote effective commercialization of sensors; future developments are also proposed.

The effect of various primers improving adhesiveness of gel polish hybrids on pH, TOWL and overall nail plates condition

BACKGROUND

Hybrid manicure is now a popular method of nail care and nail art, which is associated with its durability. Unfortunately, it has an adverse effect on pH, TOWL and overall nail plates condition and has not been investigated in detail so far.

AIMS

The aim of this study was to compare the pH and TOWL of the hand nails after using different primers. The effect of application time, breaks between applications and the method of curing and removal on those parameters and overall nail plates condition were evaluated.

PATIENTS/METHODS

An evaluation survey was conducted among 116 women. pH and TOWL measurements of the nail plate in 35 women were taken using the Courage & Khazaka. Clinical photos were made using the Fotomedicus system.

RESULTS

The measured pH values of the nail plate in the test group with gel polish hybrid on the nails were from 5.50 to 6.65, while after removal of the gel polish hybrid, the values ranged from 5.63 to 6.68. TOWL of the nail plate covered with gel polish hybrid ranged from 2.9 to 33.2 g/m² /h, whereas after removal of hybrids-from 1.9 to 45.7 g/m² /h.

CONCLUSION

Different forms of acid-free primers maintain a lower pH of the nail plate covered with a gel polish hybrid, while the acidic primer maintains higher values of the nail plate pH. The significant decrease in the nail plate TOWL following the application of gel polish hybrid indicates a reduced loss of water from the surface of the nail to the atmosphere.

Direct assessment of skin epithelial barrier by electrical impedance spectroscopy

BACKGROUND

Many skin and mucosal inflammatory disorders, such as atopic dermatitis, have been associated with an impaired epithelial barrier function, which allows allergens, pollutants, or microbes to enter the tissue and activate the immune response. The aim of this study was to establish a method to directly assess in vivo the epidermal barrier function by electrical impedance (EI) spectroscopy.

METHODS

Mice epidermal barrier was damaged by epicutaneous application of proteases and cholera toxin and by tape stripping. EI and transepidermal water loss (TEWL) were measured before and after the application. Additionally, histological analysis, immunofluorescence staining, and RT-PCR were performed on skin biopsies to evaluate the epithelial barrier.

RESULTS

A few hours after papain application, a dose-dependent reduction of EI was detected, reflecting the decreased barrier function. At the same time, an increase of TEWL was observed, with a significant negative correlation with EI, demonstrating that EI changes were directly linked to barrier defects. Twenty-four and 48 hours after the treatment, EI starts to increase to background levels, indicating tissue healing and restoration of skin barrier. Barrier disruption was confirmed by histological analysis showing an impaired stratum corneum and higher cellular infiltration after papain application. In addition, immunofluorescence staining and RT-PCR showed downregulation of molecules involved in the barrier function, such as filaggrin, occludin, and claudin-1, and mRNA levels of filaggrin, loricrin, and involucrin. Comparable results were observed after tape stripping and cholera toxin treatment.

CONCLUSION

Electrical impedance spectroscopy is a rapid and reliable diagnostic tool to detect skin barrier defects.

Comparative study into facial sebum level, pore size, and skin hydration between oily-skinned and dry-skinned Thai women

BACKGROUND

Subjective facial skin type is most frequently determined by the amount of sebum, which showed trends across subjective skin types in most previous studies while not in some. This study was conducted to evaluate the associations among subjective skin type, amount of sebum, stratum corneum hydration, and pore size in Thai women.

METHODS

Sixty-two healthy women with either self-described subjective oily or dry skin type were included and casual sebum level (CSL), sebum excretion rate (SER), clinical pore size score, mean pore area, and stratum corneum hydration were measured at several facial sites. Correlation coefficients between amount of sebum and other parameters were estimated.

RESULTS

Casual sebum level and sebum excretion rate were significantly higher in oily-skinned than dry-skinned group by 1.6-2.1 times. Mean pore area and clinical pore size score were not different between the 2 groups, nor did they correlate with CSL or SER. Corneometry was shown to be significantly higher in dry-skinned than oily-skinned group. Significant, negative correlations between corneometry and CSL were also found.

CONCLUSION

The subjective facial skin types were consistent with the amount of sebum, but not pore size or corneometry, among Thai women.

Characterization of cowhage-induced pruritus in inflamed and non-inflamed skin

BACKGROUND AND OBJECTIVE

Pruritus is a major symptom of many inflammatory diseases and impacts greatly the quality of life in patients. We aimed to specify the characteristics of experimentally induced pruritus in normal skin and in experimentally induced inflammatory dermatitis in healthy volunteers.

METHODS

Skin inflammation was induced by the repeated application of sodium lauryl sulphate (SLS 2%) on the volar forearms of 30 healthy volunteers. Inflammatory dermatitis intensity was assessed using the eczema score adapted from Frosch and Kligman. Non-histaminergic pruritus was induced by cowhage spicules rubbed on the volar forearms and recorded for 30 min on a 10-cm visual analogue scale (VAS) in both non-inflamed and inflamed skin.

RESULTS

Induction of inflammatory dermatitis by SLS resulted in a mild inflammatory dermatitis with an inflammation score of 2.3 ± 0.1 within 7 days of treatment. Cowhage-induced pruritus was of markedly higher intensity (P < 0.001), and all but two individuals had higher maximum pruritus intensity in inflamed skin as compared to non-inflamed skin, whereas the kinetics of the pruritus response were similar. The quality of cowhage-induced pruritus was significantly different with more 'burning' and 'painful sensations' in inflamed skin (P < 0.01). Maximum pruritus intensity in inflamed skin strongly correlated with maximum pruritus intensity in non-inflamed skin (r = 0.51, P = 0.004). Skin hydration, skin barrier integrity and dermatitis severity did not correlate with pruritus intensity.

CONCLUSION

Taken together, pruritus in inflamed skin is perceived as more intense, painful and burning. This may explain, in part, why pruritus is a major driver of quality-of-life impairment in patients with chronic inflammatory skin conditions such as atopic dermatitis.

Evaluation of the Soothing and Protective Properties of a Lignin Hydrolyzate

Lignins have shown remarkable antioxidant properties; acting as “scavengers” of free radicals physiologically produced by cell metabolisms; and exerting a protective action caused by the strong ability of these molecules to absorb UV radiation. Through preliminary Molecular Modeling studies and experimental studies in vivo and in vitro, a lignin hydrolysate compound has been shown to be an extremely versatile active ingredient, presenting soothing, anti-inflammatory, anti-itch, anti-oxidant, anti-aging and anti-pollution properties. The possible fields of application are therefore multiple; making this lignin hydrolysate a particularly interesting ingredient for topical dermatological compositions in the treatment of various skin disorders such as inflammation, edema, swelling, rash, redness, itching, chrono- and photo-induced skin aging. These manifestations are also the basis of more or less serious skin problems, making lignin hydrolysate capable of being used in cosmetic products for the eternal challenge of fighting skin aging, but also in medical devices that can be used to fight more painful and annoying symptoms, like those caused by dermatitis or psoriasis.

Efficacy of a Moisturizer for Pruritus Accompanied With Asteatosis in Dialysis Patients: An Open-Label, Randomized, Exploratory Study

Background

In dialysis patients, skin disorders (dryness and itching) are frequently observed and treated with a moisturizer, in the absence of clear evidence of efficacy.

Study Design

An open-label, randomized, before/after, parallel-group, comparative/exploratory study.

Setting & Participants

12 Japanese patients with chronic kidney failure undergoing maintenance hemodialysis who presented with dry skin and itching.

Intervention

Patients received a topical heparinoid moisturizer as the study drug for 2 weeks from the first day of the study treatment, followed by either a 2-week washout (group A: 6 participants) or further 2-week treatment (group B: 6 participants).

Outcomes

The primary end point was change in water content in the stratum corneum in the hypochondrium. Secondary end points included change in visual analogue scale itching score and subjective evaluations of symptoms. To evaluate safety, adverse events were also investigated.

Measurements

Water content of the stratum corneum, dryness/itching improvement rating, itching visual analogue scale/duration of itching, photographic evaluation of skin symptoms, principal investigator’s overall assessment of study drug, and adverse events.

Results

Mean water content of the stratum corneum in the combined groups significantly increased at week 2 (51.2 arbitrary units [AU] vs treatment start day, 31.6 AU; P<0.001), but significantly decreased at week 4 in group A, in which patients discontinued treatment with the study drug (39.4 AU; P = 0.005). Other efficacy end points, including the visual analogue scale itching score, were also improved by treatment with the study drug, but such improvement was not sustained after discontinuation of treatment. There were no adverse events related to the study treatment.

Limitations

Only Japanese patients were included in the study, with a small sample size.

Conclusions

Continuous application of the topical heparinoid moisturizer increased water content in the stratum corneum and lessened itching in dialysis patients.

Funding

Maruho Co, Ltd.

Trial Registration

Registered at the University Hospital Medical Information Network Clinical Trials Registry with study number UMIN000017016.

Review of Modern Techniques for the Assessment of Skin Hydration

Skin hydration is a complex process that influences the physical and mechanical properties of skin. Various technologies have emerged over the years to assess this parameter, with the current standard being electrical probe-based instruments. Nevertheless, their inability to provide detailed information has prompted the use of sophisticated spectroscopic and imaging methodologies, which are capable of in-depth skin analysis that includes structural and composition details. Modern imaging and spectroscopic techniques have transformed skin research in the dermatological and cosmetics disciplines, and are now commonly employed in conjunction with traditional methods for comprehensive assessment of both healthy and pathological skin. This article reviews current techniques employed in measuring skin hydration, and gives an account on their principle of operation and applications in skin-related research.

Anatomical site variation of water content in human skin measured by the Epsilon: A pilot study

Background

This pilot study aimed to investigate the anatomical site variation of water content of the stratum corneum (SC) on the body by measuring skin capacitance with the Epsilon, a new generation corneometer with multiple sensors. Secondly, values of the Epsilon were compared to values measured by conventional single sensor corneometers.

Methods

The hydration status of SC was measured in 15 healthy Caucasian volunteers with the Epsilon at five body sites (cheek, lower forearm, mid‐calf, lower back and abdomen). Transepidermal water loss (TEWL) was measured with the Aquaflux to get more insight into the condition of the skin barrier. A literature search was performed to compare Epsilon values with conventional corneometers.

Results

The tested anatomical locations showed significant differences in water content (P < 0.001) with large interindividual variations; highest values were found in the cheek (11.64ε) and lowest values in the mid‐calf (4.43ε). No correlation between water content and TEWL was found. In general, Epsilon values were lower compared to values of conventional corneometers, with a similar trend.

Conclusion

This pilot study showed significant variations in water content at different skin locations measured by the Epsilon. Moreover, the Epsilon measured consistent lower values compared to single sensor corneometers. Further validation of the device is recommended.

Noninvasive measures in atopic dermatitis

PURPOSE OF REVIEW

To summarize the current knowledge on the morphology, functionality and biochemical composition of the skin in allergic reactions. We address novel noninvasive techniques that promise to disclose intimate mechanisms of skin allergy in vivo. Epidermal barrier is not just a static wrap of the organism but rather a dynamic field for immunological, biophysical and biochemical processes and serves as a bio-sensor for exogenous danger signals.

RECENT FINDINGS

Classical biophysical methods are amended by novel in-vivo techniques, such as Raman spectroscopy, analysing the skin microcomposition and develop epidermal profiles. Visualization techniques, such as reflectance spectroscopy and optical coherence tomography (OCT) are employed in studying the micro-morphological changes in the skin of allergic patients.

SUMMARY

The noninvasive assessment of skin functions, micro-morphology and biochemical as well as immunological pathways will help to better understand skin allergies. They will allow to detect subtypes, for example in atopic dermatitis and to develop specific treatment modalities.