Transepidermal Water Loss Measurements Research Articles

Visualizing the in-vivo application of zinc in sensitive skin using reflectance confocal microscopy

Findings obtained on objective assessments to evaluate sensitive skin do not correlate well with the symptomatology. We utilized reflectance confocal microscopy (RCM) to compare transepidermal application of zinc in sensitive and non-sensitive skin. Thirty-six subjects participated in this study. They were divided into groups based on lactic acid sting test (LAST):‘stinger’ and ‘non-stinger’; transepidermal water loss (TEWL) measurements; and sensitivity self-assessments: ‘sensitive’ and ‘non-sensitive’. RCM images were taken to visualize transepidermal application of topically-applied zinc. The intensity of zinc reflectance at different depths was measured by ImageJ software. Based on LAST scores, the ‘stinger’ group showed significantly higher reflectance of zinc at 8 µm (stratum corneum) [face (P < 0.001), forearm (P = 0.004)], and at 80–104 µm (dermo-epidermal junction layer) on the face. High-TEWL group showed increased zinc reflectance at 8–24 µm (tight junction layer, P < 0.001). There were no significant differences amongst subjects self-reporting ‘sensitive’ and ‘non-sensitive’ skin. RCM demonstrates that in sensitive skin, there is deeper and higher reflectance of zinc at multiple depths. Structural differences are also visualized. We suggest that RCM is a useful tool for evaluating skin barrier integrity.

Instrumental evaluation of skin barrier function and clinical outcomes during dupilumab treatment for atopic dermatitis: An observational study.

Atopic dermatitis (AD) is a chronic, inflammatory skin disease characterized by pruritus, xerosis, and skin barrier dysfunction. Skin barrier alteration is associated with an increase in trans-epidermal water loss (TEWL) and reduction in skin hydration. Dupilumab is a monoclonal antibody targeting interleukin-13 modulating pro-inflammatory signal transduction, which has been approved for moderate to severe AD. The aim of this study is to evaluate the effects of Dupilumab on skin barrier functions, using non-invasive instruments and clinical evaluation. Thirty patients affected by moderate-severe AD, who had been administered dupilumab, were evaluated by clinical examination and through the instrumental measurements of TEWL and corneometry at the baseline (T0) and 8weeks (T1) on lesional skin. The clinical evaluation was performed using the Eczema Area and Severity Index (EASI) score. Moreover, a Dermatology Life Quality Index (DLQI) and 7-day numeric rating scale (NRS) questionnaires were administered to each patient. The instrumental parameters of skin barrier recovery confirmed the clinical improvement outcomes with a statistically significant reduction of TEWL at T1. Our data confirm the clinical outcomes already reported in the literature and show that there was an inverse proportional correlation between TEWL levels and clinical severity after 8weeks of treatment with dupilumab.

Prospective Randomized Controlled Trial on the Effects of Almonds on Facial Wrinkles and Pigmentation.

Background: Almonds have long been studied as a rich source of fatty acids, phytochemical polyphenols and antioxidants such as vitamin E. A recent study compared almond supplementations to a calorie-matched intervention for 16 weeks, yielding statistically significant improvement in wrinkle severity in postmenopausal women with Fitzpatrick skin types I and II that received almonds. This study furthers that assessment with a larger population and duration of 24 weeks to assess the influence of almond consumption on wrinkle severity, skin pigmentation and other skin biophysical profiles. Objective: To investigate the effects of almond consumption on photoaging such as wrinkles and pigment intensity as well as facial biophysical parameters such as sebum production, skin hydration and water loss. Design and interventions: A prospective, randomized controlled study assessed postmenopausal women with Fitzpatrick skin types I or II who consumed 20% of their daily energy consumption in either almonds or a calorie-matched snack for 24 weeks. A facial photograph and image analysis system was used to obtain standardized high-resolution photographs and information on wrinkle width and severity at 0, 8, 16 and 24 weeks. Measurements of transepidermal water loss (TEWL), skin pigmentation, skin hydration and sebum production were also completed at each visit. Results: The average wrinkle severity was significantly decreased in the almond intervention group at week 16 and week 24 compared to baseline by 15% and 16%, respectively. Facial pigment intensity was decreased 20% in the almond group at week 16 and this was maintained by week 24. There were no significant differences in skin hydration or TEWL in the almond group compared to the control, although sebum excretion was increased in the control group. Conclusion: The daily consumption of almonds may improve several aspects of photoaging such as facial wrinkles and pigment intensity in postmenopausal women. In conclusion, the daily consumption of almonds may contribute to the improvement of facial wrinkles and reduction of skin pigmentation among postmenopausal women with Fitzpatrick skin types I and II.

Did human evolution in skin of color enhance the TEWL barrier?

United States will soon be a nation of color; however, much of our knowledge of normal skin disease, and treatment thereof is based on white skin. We and others have attempted to elucidate any potential differences and advantages/disadvantages in skin function that have emerged during homo sapiens evolution post major migration from Eastern Africa. We investigated differences in one stratum corneum function by examining transepidermal water loss (TEWL) measurements in skin of color compared to Caucasian skin. TEWL, a measure of insensible water loss through stratum corneum, plays a major role in human survival. A comprehensive literature search was conducted to procure relevant papers that measured baseline TEWL in skin of color and Caucasian skin. The data show wide contradiction in results for all skin of color groups and white skin and, therefore, no conclusion can be made based on this question. We suggest this variation may be due to experimental confounding variables that impact TEWL quantification, such as anatomic site and sample size subject to further analysis and focus.

Prevention of Hand Eczema among Nurse Apprentice (PREVEDERM): An Interventional Study.

Workers in the healthcare sector are at high risk of developing occupational hand eczema mainly due to frequent exposure to irritants and/or allergens. Amongst workers in healthcare, nurses are at higher risk of developing hand dermatitis. To evaluate the effectiveness of a short educational intervention program in preventing occupational hand eczema in nurse apprentices, using two objective tools, namely TEWL and EH, and the HECSI score. Data regarding professions, wet work exposure, activities performed during working hours, self-reported eczema were collected from 230 nurse students, divided in two study groups: the intervention and the control group (CG). The intervention group (IG) was given education about risks and proper skin care and was provided with cosmeceuticals to be used for skin care during hospital activity. The evaluation of skin properties was performed using questionnaires, HECSI score, measurement of transepidermal water loss (TEWL) and epidermal hydration (EH). A number of 139 apprentice nurses completed the study. Of those participants who completed the study, 19.1% from CG and 19.6% from IG reported, at T1, hand eczema in the last 3 months, while at T2 (3 months later), 59.52 % of the CG and only 11.34 % from the IG stated having eczema in the last 3 months. In the IG, results showed an improvement of CM with 17% and of TEWL with 16%, with only a 0.5% improvement of CM in CG and a marked impairment of TEWL by 33%. Hand eczema is a common occupational dermatosis affecting the medical staff, even during apprenticeship. Early preventive training programs are effective in reducing the burden of occupational contact dermatitis.

Accelerated Wound Closure of Deep Partial Thickness Burns with Acellular Fish Skin Graft.

Thermal injuries are caused by exposure to a variety of sources, and split thickness skin grafts are the gold standard treatment for severe burns; however, they may be impossible when there is no donor skin available. Large total body surface area burns leave patients with limited donor site availability and create a need for treatments capable of achieving early and complete coverage that can also retain normal skin function. In this preclinical trial, two cellular and tissue based products (CTPs) are evaluated on twenty-four 5 × 5 deep partial thickness (DPT) burn wounds. Using appropriate pain control methods, DPT burn wounds were created on six anesthetized Yorkshire pigs. Wounds were excised one day post-burn and the bleeding wound beds were subsequently treated with omega-3-rich acellular fish skin graft (FSG) or fetal bovine dermis (FBD). FSG was reapplied after 7 days and wounds healed via secondary intentions. Digital images, non-invasive measurements, and punch biopsies were acquired during rechecks performed on days 7, 14, 21, 28, 45, and 60. Multiple qualitative measurements were also employed, including re-epithelialization, contraction rates, hydration, laser speckle, and trans-epidermal water loss (TEWL). Each treatment produced granulated tissue (GT) that would be receptive to skin grafts, if desired; however, the FSG induced GT 7 days earlier. FSG treatment resulted in faster re-epithelialization and reduced wound size at day 14 compared to FBD (50.2% vs. 23.5% and 93.1% vs. 106.7%, p < 0.005, respectively). No differences in TEWL measurements were observed. The FSG integrated into the wound bed quicker as evidenced by lower hydration values at day 21 (309.7 vs. 2500.4 µS, p < 0.05) and higher blood flow at day 14 (4.9 vs. 3.1 fold change increase over normal skin, p < 0.005). Here we show that FSG integrated faster without increased contraction, resulting in quicker wound closure without skin graft application which suggests FSG improved burn wound healing over FBD.

The effectiveness of Oral Superoxide Dismutase (SOD) on total antioxidant status, Trans Epidermal Water Loss (TEWL) and sebum concentration in photo aging skin

Introduction: Aging is a progressive process of decrease in organs functions and capacity, including the skin. Photoaging is extrinsic aging mainly occur due to ultraviolet (UV) exposure. Methods: This study is a clinical trial research design with one group pre-post test. All subjects who were exposed to UV for approximately 3-4 hours. All subjects signed an informed consent and were interviewed accordingly. Photoaging was diagnosed clinically by three dermatologists according to Glogau type II classification such as dynamic wrinkles, palpable keratosis, visible lentigo senilis, and smiley line. SOD 250 IU was given to all subjects twice daily for 60 days. Laboratory examinations such as TAS, TEWL, and sebum concentration were done pre and post-intervention. Results: A total of 25 subjects, Fitzpatrick skin type 4 were included in this study. There were 14 males and 11 females with 20 subjects age 30-40 years old and 5 subjects age 25-29 years old. Fourteen (56%) out of 18 subjects from low TAS group have normal TAS post-treatment with SOD. McNemar test showed a significant increase in TAS value pre and post-treatment with SOD (p&lt;0.05). TEWL measurement on cheek showed 9 out of 10 subjects from the strained group have normal TEWL post-treatment, while all 3 subjects from the critical group have normal TEWL value. Measurement on the forehead showed 7 subjects from the strained group have a normal TEWL. Sebumeter on the forehead showed 17 subjects from dry skin group 14 (56%) subjects have normal skin, 1 (4%) subject becomes oily, and 2 subjects remains dry post-treatment with SOD for 60 days. All subjects with dry skin on U zone become normal skin post-treatment. Conclusion: SOD significantly increased TAS value, decreased TEWL, and improvement of skin dryness post-treatment with SOD for 60 days.

Efficacy of a Protective Hand Cream versus a Conventional Cream to Improve Skin Barrier Function among Pediatric Intensive Care Unit Healthcare Workers: A Pilot Study

Background: Hand hygiene is one of the most effective procedures for preventing health care-associated infection. Barrier creams are used to prevent the irritant effect caused by occupational exposure. Objective: To compare an aluminum chlorohydrate-containing hand cream and a conventional cream in health-care workers (HCWs) by using clinical assessment score and quantitative measurement of transepidermal water loss (TEWL). Materials and Methods: A double-blinded, randomized, placebo-controlled trial was performed in pediatric intensive care unit HCWs. The subjects were assigned to regularly use the given cream (one fingertip unit per time, equal to 0.5 gram) after washing their hands with either 4% chlorhexidine gluconate or alcohol hand rub, which is 70% alcohol, glycerin, D-panthenol. The clinical assessment score, ranging from 0 to 3 points per item, were performed by the investigator evaluating for erythema, dryness, scaling, vesicles, fissuring and lichenification, and by the subject evaluating the redness, itching, tightness, dryness and sweating, together with TEWL assessment in a controlled environmental condition at day 0, 7, and 14. Results: Sixty HCWs were equally divided for each product. Barrier cream and conventional cream, amount used were 32.20 g and 26.43 g, respectively. At day 14, the clinical assessment score by the investigator and by the subject were reduced by 40.02% and 43.38% in the barrier cream group, and 35.5% and 47.83% in the conventional cream group (p&lt;0.001. However, the TEWL in both groups was not significantly different from the baseline. Both products were well tolerated. Conclusion: The amount of cream applied by HCWs was lower than assigned. Both barrier cream and conventional cream can clinically improve the clinical score. Frequent and regular use of hand creams should be encouraged to decrease or prevent skin irritation and hand dermatitis. Keywords: Protective hand cream, Transepidermal water loss, Healthcare workers, Hand hygiene practices, Pediatric intensive care unit

Topical and transdermal delivery with diseased human skin: passive and iontophoretic delivery of hydrocortisone into psoriatic and eczematous skin.

Psoriasis and atopic dermatitis (eczema) are both common immune-mediated inflammatory skin diseases associated with changes in skin's stratum corneum lipid structure and barrier functionality. The present study aimed to investigate healthy, eczematous, and psoriatic excised human tissue for the effect of non-infectious skin diseases on skin characteristics (surface color, pH, transepidermal water loss, electrical resistance, and histology), as well as on permeation and retention profile of hydrocortisone. Further, differences in percutaneous absorption on application of iontophoresis on healthy and diseased skin were also investigated. Measurements of transepidermal water loss and electrical resistance showed a significant difference in psoriasis skin samples indicating a damaged barrier function. In vitro permeation studies on full-thickness human skin using vertical diffusion cells further confirmed these results as the drug amount retained in the psoriatic tissue was significantly higher when compared with the other groups. Despite no significant difference, the presence of the drug in the receptor chamber in both diseased groups can be concerning as it suggests the increased possibility of systemic absorption and adverse reactions associated with it in the use of topical corticosteroids. Application of anodal iontophoresis resulted in greater distribution of hydrocortisone into deeper layers of skin and the receptor chamber, in comparison to passive permeation. However, no significant differences were observed due to the healthy or diseased condition of skin.

Development and evaluation of a quality control system based on transdermal electrical resistance for skin barrier function in vitro.

In vitro skin permeation experiments are highly relevant for pharmaceutical, cosmetic, agricultural developments, and regulatory evaluation. A key requirement is the skin barrier integrity, that is accompanied by an intact stratum corneum (SC) which implements high skin quality. A variety of integrity tests are currently available, for example, measurement of transepidermal water loss, monitoring the permeation of tritiated water and the measurement of transdermal electrical resistance (TER). We aimed for a non-destructive examination of barrier integrity as quality control system, based on TER. Therefore, the in-house developed instrument SkinTER measures electrical resistance on excised human skin samples in a non-invasive and easy-to-use pattern. In this proof of concept study, we compared three human in vitro skin models with focus on their TER and permeation properties. The skin integrity was impaired to mimic conditions of skin during age, lifestyle (eg, shaving) or diseases (eg, obesity, psoriasis, and atopic dermatitis). The OECD permeation marker caffeine was correlated to the corresponding TER value. A correlation between both was obtained by having a Pearson coefficient of -0.830. Hereby, a minimum TER value for intact skin samples of ~1.77kΩ*cm2 was suggested. Intact samples are significantly different (α=≤0.05) to their impaired counterparts in flux and TER values. The new SkinTER instrument gives a quick and non-invasive feedback on skin quality before a permeation experiment.

Epoxide hydrolase 3 (Ephx3) gene disruption reduces ceramide linoleate epoxide hydrolysis and impairs skin barrier function

The mammalian epoxide hydrolase (EPHX)3 is known from in vitro experiments to efficiently hydrolyze the linoleate epoxides 9,10-epoxyoctadecamonoenoic acid (EpOME) and epoxyalcohol 9R,10R-trans-epoxy-11E-13R-hydroxy-octadecenoate to corresponding diols and triols, respectively. Herein we examined the physiological relevance of EPHX3 to hydrolysis of both substrates in vivo. Ephx3−/− mice show no deficiency in EpOME-derived plasma diols, discounting a role for EPHX3 in their formation, whereas epoxyalcohol-derived triols esterified in acylceramides of the epidermal 12R-lipoxygenase pathway are reduced. Although the Ephx3−/− pups appear normal, measurements of transepidermal water loss detected a modest and statistically significant increase compared with the wild-type or heterozygote mice, reflecting a skin barrier impairment that was not evident in the knockouts of mouse microsomal (EPHX1/microsomal epoxide hydrolase) or soluble (EPHX2/sEH). This barrier phenotype in the Ephx3−/− pups was associated with a significant decrease in the covalently bound ceramides in the epidermis (40% reduction, p < 0.05), indicating a corresponding structural impairment in the integrity of the water barrier. Quantitative LC-MS analysis of the esterified linoleate-derived triols in the murine epidermis revealed a marked and isomer-specific reduction (∼85%) in the Ephx3−/− epidermis of the major trihydroxy isomer 9R,10S,13R-trihydroxy-11E-octadecenoate. We conclude that EPHX3 (and not EPHX1 or EPHX2) catalyzes hydrolysis of the 12R-LOX/eLOX3-derived epoxyalcohol esterified in acylceramide and may function to control flux through the alternative and crucial route of metabolism via the dehydrogenation pathway of SDR9C7. Importantly, our findings also identify a functional role for EPHX3 in transformation of a naturally esterified epoxide substrate, pointing to its potential contribution in other tissues.

Hydrogel or ointment? Comparison of five different galenics regarding tissue breathability and transepidermal water loss

PurposeFive different galenics were analyzed and compared concerning tissue breathability and gas exchange with the environment after an application period of 6 h on pig ear skin. Aim was to find the most suitable galenics for efficient moist treatment for everyday injuries (abrasions, lacerations and cuts) without influencing the transepidermal water loss. MethodsA quantity of 0.1 g of the different test preparations was applied once topically to an area of 2 cm2. The analysis of the breathability was performed by TEWL (transepidermal water loss) measurements in the first hour after product application. The moisture retention effect was assessed by corneometry in the first 5 h after product application. ResultsThe hydrogel preparations showed a higher breathability in contrast to a semi-occlusive ointment and petrolatum. The same applies to the moisture penetration of the skin. Here, all hydrogel formulations showed the highest tissue hydration. After 3 h an additional increase in moisture was observed for the areas treated with Tyrosur® CareExpert Wound Gel and the ointment. ConclusionIn contrast to petrolatum and the semi-occlusive ointment, treatment with the hydrogels led to a preservation of the breathability and good moistening of the tissue, which is due to the galenics of the gels consisting of water, carbomer and propylene glycol. The increase in moisture after 3 h in areas treated with Tyrosur® CareExpert Wound Gel and the semi-occlusive ointment indicates a sustained moisturizing effect mediated by dexpanthenol.

Nicotine loaded dissolving microneedles for nicotine replacement therapy

Nicotine replacement therapy is a medically approved means to quit smoking. Microneedle devices could be engineered in such a way to provide rapid delivery of nicotine. The main objective of this study was to explore the feasibility of nicotine delivery from microneedles via the transdermal route. Nicotine loaded microneedles were prepared using a mold casting technique with polyvinylpyrrolidone as the water-soluble polymer. The microneedles were characterized for their height, diameter, and tip width by microscopic observation. The nicotine loaded microneedles were characterized for in vitro release profile and skin permeation profile. The pharmacokinetic parameters of nicotine loaded microneedles were compared with an intravenous administration of nicotine in Sprague Dawley rats. The in vivo skin resealing kinetics was studied using TEWL (Transepidermal water loss) measurements after insertion of microneedles as an indicator of skin barrier function. In vivo, pharmacokinetic studies revealed that nicotine from microneedles showed immediate release profile with Cmax (70.10 ± 3.55 ng/mL) being achieved within the first hour. Overall, nicotine loaded into microneedles could be a potential pain-free and minimally invasive treatment option for nicotine replacement therapy.

Assessment of skin barrier function using skin images with topological data analysis

Recent developments of molecular biology have revealed diverse mechanisms of skin diseases, and precision medicine considering these mechanisms requires the frequent objective evaluation of skin phenotypes. Transepidermal water loss (TEWL) is commonly used for evaluating skin barrier function; however, direct measurement of TEWL is time-consuming and is not convenient for daily clinical practice. Here, we propose a new skin barrier assessment method using skin images with topological data analysis (TDA). TDA enabled efficient identification of structural features from a skin image taken by a microscope. These features reflected the regularity of the skin texture. We found a significant correlation between the topological features and TEWL. Moreover, using the features as input, we trained machine-learning models to predict TEWL and obtained good accuracy (R2 = 0.524). Our results suggest that assessment of skin barrier function by topological image analysis is promising.

Wearable Patch-Type Transepidermal Potential Measurement Device with Porous Microneedle

The skin is a structure that covers the surface of the body and separates the inside and outside of the body. The stratum corneum on the surface of the skin has a barrier function that prevents the entry of foreign substances and excessive moisture evaporation. It has been reported that impaired barrier function can lead to dryness and diseases of the skin. Therefore, it is important to evaluate the barrier function. Currently, the measurement of transepidermal water loss (TEWL) is used as the main method. The barrier function is evaluated based on the fact that water evaporation increases when barrier function is reduced. This method, however, requires strict temperature and humidity control, and can be used only in designated locations as a result. As another indicator of barrier function, it has been known that the transepidermal potential (TEP), a potential difference in the thickness direction in the epidermis, can be used [1], but there was no practical method to measure it.In this study, we developed a wearable patch-type TEP measurement device that can evaluate barrier function with minimal invasiveness. To measure the TEP, it is necessary to connect electrodes to the inside and outside the epidermis. In order to connect electrodes to the inside the epidermis, we developed a tip-conducting porous microneedle array by insulating except for the tip of a porous microneedle array that is entirely conductive [2]. In order to make the device thinner and more flexible, an Ag/AgCl reference electrode was developed, in which the electrode and liquid junction were screen-printed on a thin film. We then combined a microneedle array and a flexible electrode into a patch-type device. In addition, we are now developing a small voltmeter that can be connected to a patch-type device to make a wearable device for long-term TEP monitoring.First, a tip-conducting porous microneedle array was developed to connect minimally invasively to the interior of the epidermis. The microneedle array was prepared by mixing the monomer solution with the porogen solution, pouring it into a mold and solidifying it with UV light. The microneedle array was placed on a block of Polydimethylsiloxane (PDMS), pressed down with a 10 g weight, and the needle tips were buried in PDMS block while the vapor deposition of the parylene C coating. The porogen was then dissolved in an organic solvent. The distribution of parylene C at the tip of the needle was evaluated by using energy dispersive X-ray spectroscopy (EDX). In addition, the electrical resistance of the microneedle array was measured to evaluate the insulation. Next, a flexible Ag/AgCl reference electrode was developed. Plastic wrapping film was used as a substrate, Ag/AgCl paste was printed by screen printing, and polyvinylpyrrolidone (PVP) gel containing KCl was dripped over it and dried. A waterproof adhesive tape with a 0.1 mm diameter hole was then applied, and a liquid mixture of polyurethane and cellulose acetate dissolved in an organic solvent and KCl powder was applied and dried. The prepared electrode was then immersed in Ringer's solution and the electrode potential was measured for 24 hours to evaluate the deviation of the electrode potential. Then, a patch-type device was fabricated by combining a tip-conducting porous microneedle array with a flexible Ag/AgCl reference electrode. A microneedle array was attached to the electrode using a waterproof adhesive tape. The device was used to measure the TEP of porcine skin samples, and the measured values were evaluated in comparison with the results obtained by the conventional method, which is not practical due to its high invasiveness.The fabricated microneedle array was successfully insulated except for the tip of the needle (Fig. 1A). The deviation of the electrode potential of the fabricated flexible electrodes was less than 5 mV after 24 hours of measurement. The fabricated device was thin and flexible (Fig. 1B). The measured TEP values of the fabricated device were almost consistent with those of the conventional method (Fig. 1C). Furthermore, we are now developing a small wristwatch-type voltmeter. In conclusion, this device could be a wearable device that can monitor TEP minimally invasively and for a long time.

Topical 0.5% Timolol Maleate Significantly Enhances Skin-Barrier Restoration After Fractional Carbon Dioxide Laser Treatment for Acne Scars.

Skin barrier is often compromised following ablative fractional carbon dioxide laser (AFCO2 ) therapy for acne scarring. The resultant downtime, even of a few days' duration, can be of significant concern to patients. We evaluated the efficacy and safety of topical 0.5% timolol maleate (TM) for its role in short-term restoration of the skin's biophysical properties after laser treatments. This double-blind, placebo-controlled trial included participants aged 18-50 years with atrophic acne scars for at least 3 months. After undergoing laser therapy, they applied 0.5% TM to one cheek and normal saline to the contralateral cheek (control) for 7 days. Corneometry, transepidermal water loss (TEWL) measurement, colorimetry, and clinical outcome parameters (erythema, edema, crusting, pruritus, and tightness scores) were evaluated at baseline and 48, 96, and 168 hours after AFCO2 treatment. Twenty-five healthy participants completed the study. Most participants had Fitzpatrick skin phototype IV. The TM-treated side showed statistically higher corneometry values and lower TEWL than the control side at every follow-up visit (P < 0.001). The crusting score at 96 hours post-AFCO2 treatment was also significantly better on the TM side. No adverse events occurred during the follow-up period. Application of topical 0.5% TM twice daily improves the skin-barrier function and might promote re-epithelialization after laser procedures. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Elevated Skin pH Is Associated With an Increased Permeability to Synthetic Urine.

The aim of this study was to investigate the permeability of the skin following cleansing activities and its susceptibility to synthetic urine penetration. Ten healthy volunteers (aged 22-58 years) participated in the study, which was conducted in a university bioengineering laboratory. Tape stripping and sodium lauryl sulfate were used to simulate the physical and chemical irritation exacerbated by frequent cleansing activities, respectively. An untreated site also was selected to evaluate responses of intact skin. Synthetic urine was then applied for a period of 2 hours. Measurements of transepidermal water loss and skin pH were taken at baseline and after each challenge. To quantify the permeability of the skin following exposure, desorption curves of transepidermal water loss were measured and skin surface water loss was calculated. Chemically irritated skin, characterized by increased pH (7.34 ± 0.22), demonstrated an increased permeability to urine, as reflected by a significant increase in mean skin surface water loss (46,209 ± 15,596 g/m2) compared to both the intact (14,631 ± 6164 g/m2) and physically irritated (14,545 ± 4051 g/m2) skin (P = .005 in both cases). In contrast, the differences between the intact and physically irritated skin were not significant (P = .88). Permeability of the skin to irritants is influenced by the status of the skin and its acid mantle. These highlight the need to reevaluate the frequency of cleansing activities, along with the choice of product in clinical settings, favoring the use of pH-balanced cleansers.

Comparison of transepidermal water loss and skin hydration in diabetics and nondiabetics.

Pruritus is common in patients with diabetes mellitus (DM), and may lead to complex dermatological conditions if left untreated. Pruritus can be caused by increased transepidermal water loss (TEWL) and reduced skin hydration. To compare TEWL and skin hydration in patients with DM and controls, and to investigate associations between TEWL and skin hydration with glycated haemoglobin (HbA1c), fasting blood sugar (FBS), treatment, peripheral neuropathy (PN) and age in patients with diabetes. This was a prospective, case-control study carried out at a tertiary medical centre in Kuala Lumpur, Malaysia. TEWL and skin hydration measurements were taken at six different body sites in both groups. In total, 146 patients (73 cases, 73 controls) were included (24 men and 49 women in each group). No significant difference in TEWL or skin hydration was seen between patients with DM and controls, but there were significant reductions in skin hydration in patients with DM who had FBS > 7mmol/L (P<0.01) or PN (P<0.01). There was a reduction in TEWL over the anterior shin in patients with HbA1c levels > 6.5% (P<0.02) and an increase in TEWL on the flank in patients on insulin injections at doses of > 1U/kg/day (P<0.01). In participants > 45years old, there was a significant reduction in TEWL (P=0.04) and hydration (P<0.04) in the DM and control groups, respectively. There was no difference in TEWL and skin hydration in patients with DM compared with controls. In the DM group, reduction in skin hydration was associated with uncontrolled FBS and PN but not with HbA1c or DM treatment, whereas TEWL was lower in patients with FBS > 8mmol/L and increased in patients with higher insulin requirement.

A Study of Skin Physiology, Sensation and Friction of Nonwoven Fabrics Used in Absorbent Hygiene Products in Neutral and Warm Environments

Absorbent hygiene products like diapers, feminine hygiene, and wet wipes are life necessities. These products commonly use nonwoven fabrics as the layer that is in contact with the skin. Their performance in terms of skin health and comfort is receiving increased attention because of the existence of concerns for skin health issues such as skin irritation and dermatitis, and the large influence of skin sensation on individuals' preference. Friction is usually recognized as an important factor for skin comfort and dermatitis issues, but there is a lack of understanding of the relationship between friction and skin physiology, skin sensation, in the use of absorbent hygiene products. This study reports a measurement of friction in vivo with the evaluation of skin physiology and sensation in neutral and warm environments to explore the effects of fabric and friction on skin comfort. Friction tests between the volar forearm and nonwoven fabrics were conducted with the measurement of transepidermal water loss, skin redness, and the evaluation of subjective skin sensation. The interaction between skin and eight nonwoven fabrics with a surface roughness (arithmetic mean height) between 3 μm and 20 μm was evaluated in neutral (22 °C) and warm (35 °C) environments. Skin physiological changes after friction were able to be detected quantitatively by the transepidermal water loss and skin redness measurement. In the warm environment, there was significantly higher friction, less pleasantness, more changes in transepidermal water loss but not in skin redness. The friction can only relate to skin physiology and sensation in the neutral environment while the surface roughness of fabrics related to them in both neutral and warm environments. Both rough and smooth fabrics caused high friction in the warm environment, but the rough fabric caused a higher adverse impact on skin physiology and sensation than smooth fabrics that suggested the adhesion and deformation friction could have different effects on skin comfort. Deformation friction is more likely to have effects on skin physiology and pleasantness sensation than adhesion friction. The pleasantness sensation has a negative relationship with skin physiology. A more unpleasant sensation can indicate more impact on skin physiology. This provides a potential that the unpleasant sensation can be a precaution signal for the adverse effects on skin physiology.

Skin tape sampling technique identifies proinflammatory cytokines in atopic dermatitis skin

BackgroundMonitoring the effects of biologic therapies in skin diseases will benefit from alternative noninvasive skin sampling techniques to evaluate immune pathways in diseased tissue early and longitudinally. ObjectiveTo establish a minimally invasive profiling of skin cytokines for diagnosis, therapeutic response monitoring, and clinical research in atopic dermatitis (AD) and other skin diseases, particularly in pediatric cohorts. MethodsWe developed a novel method for cytokine profiling in the epidermis using skin tape strips (STSs) in a setting designed to maximize the efficiency of protein extraction from STSs. This method was applied to analyze STS protein extracts from the lesional skin of children having AD (n = 41) and normal, healthy controls (n = 22). A total of 20 cytokines were probed with the ultrasensitive Mesoscale multiplex cytokine assay. ResultsA significant increase in interleukin (IL)-1b (P < .01), IL-18 (P < .001), and IL-8 (P < .001) with a decrease in IL-1a (P < .001) in the stratum corneum of AD lesional skin was found. Concurrently, an increase in markers associated with type 2 inflammatory response was readily detectable in AD lesional skin, including C-C motif chemokine ligand (CCL) 22, CCL 17, and thymic stromal lymphopoietin (TSLP). The levels of IL-1b, IL-18, and TSLP exhibited positive correlations with the AD severity index (Scoring AD index) and skin transepidermal water loss (TEWL), whereas an inverse correlation between IL-1a and Scoring AD index and IL-1a and TEWL was found. The levels of CCL17, CCL22, TSLP, IL-22, and IL-17a correlated with skin TEWL measurements. ConclusionUsing minimally invasive STS analysis, we identified cytokine profiles easily sampled in AD lesional skin. The expression of these markers correlated with disease severity and reflected changes in TEWL in lesional skin. These markers suggest new response assessment targets for AD skin. Trial RegistrationClinicalTrials.gov Identifier: NCT03168113.