The effects of water exposure on biophysical properties of normal skin

Skin Barrier Function Assessment: Electrical Impedance Spectroscopy Is Less Influenced by Daily Routine Activities Than Transepidermal Water Loss

BACKGROUND

Skin barrier function assessment is commonly done by measuring transepidermal water loss (TEWL). An important limitation of this method is the influence of intrinsic and extrinsic factors. Electrical impedance spectroscopy (EIS) is a lesser-established method for skin barrier function assessment. Some influential factors have been described, but no guidelines exist regarding the standardization of these measurements.

OBJECTIVE

To evaluate the effect size of daily routine activities on TEWL and EIS, as well as their correlation with age and anatomical differences.

METHODS

Healthy participants (n=31) were stratified into three age groups (18-29, 30-49, and ≥50 years). In a climate-controlled room, EIS and TEWL measurements were performed on the left and right volar forearm and abdomen.

RESULTS

Body cream application decreased TEWL and EIS values after 15 and 90 minutes. Skin washing decreased TEWL for 15 minutes and EIS values for at least 90 minutes. TEWL was increased 5 minutes after moderate to intense exercise. Coffee intake increased TEWL on the abdomen after 60 minutes. TEWL and EIS values did not correlate with participants' age and no anatomical differences were observed. No correlation was observed between TEWL and EIS.

CONCLUSION

Body cream application and skin washing should be avoided at least 90 minutes prior to measurements of TEWL and EIS. Exercise and coffee intake should also be avoided prior to TEWL measurements. EIS may be a promising tool for skin barrier function assessment as it is less affected by daily routine activities than TEWL.

The Effects of Incontinence Pad Application on Loaded Skin With Reference to Biophysical and Biochemical Parameters: An Exploratory Cohort Study Using a Repeated-Measures Design

PURPOSE

The purpose of this study was to evaluate temporal changes in skin responses following exposure to moisture alone or moisture in combination with mechanical loading.

DESIGN

Comparison cohort with a repeated-measures design.

SUBJECTS AND SETTINGS

The sample comprised 12 healthy volunteers. Participants were purposely sampled from 2 different age groups; half were 32 to 39 years old and half were 50 to 62 years old. Participants identified as White, Black, or mixed; 83% (n = 10) identified as White; 8 (67%) were female.

METHODS

Four sites at the sacrum were challenged with the application of specimens taken from 2 absorbent products; the pad specimens were applied dry or saturated with synthetic urine (SU; pH = 8); a further site from the sacral skin was also selected and used as a control. Skin assessments were performed at different points in time: (1) 60 minutes after exposure to dry or SU-saturated pad specimens; (2) 60 minutes after exposure to pads and mechanical loading (application of pressure in the form of 45°C high sitting); and (3) 30 minutes after removal of all pads (recovery period). Outcome measures were transepidermal water loss (TEWL), stratum corneum (SC) hydration, erythema, pH, and skin inflammatory biomarkers measured at each of the time points described earlier.

RESULTS

The control site and those exposed to dry pads showed minimal time-dependent changes irrespective of the parameter investigated. In contrast, significant increases in TEWL (P = .0000007) and SC hydration responses (P = .0000007) were detected at the sites under absorbent pad specimens after saturation with SU (exposure to moisture). In some participants, TEWL and SC hydration parameters were significantly higher during pressure application. Skin pH remained in the mildly acidic range throughout the test session, and no consistent trends were observed with erythema. Skin inflammatory biomarkers also exhibited considerable variability across participants; none changed significantly over time. Significant differences (P = .02) were also detected following the exposure of moisture in combination with pressure.

CONCLUSION

We evaluated an array of parameters to identify changes following skin exposure to 2 absorbent pads in the presence and absence of SU and mechanical loading. Analysis revealed changes in skin barrier properties in the presence of moisture and/or pressure. This observation suggests a need for frequent pad changing as well as periods of skin off-loading to protect the skin health of individuals with incontinence.

Paclitaxel Induces Epidermal Molecular Changes and Produces Subclinical Alterations in the Skin of Gynecological Cancer Patients

Simple Summary

Skin toxicity is one of paclitaxel’s adverse effects. However, its real impact on the skin could be underestimated as these alterations can also appear asymptomatic. We have observed that paclitaxel modifies gene and protein expression of skin markers in a 3D epidermis model, and impairs physical, physiological, and biomechanical properties of the skin in gynecologic cancer patients. These subclinical alterations might be avoided by using prophylactic measures during treatment to prevent possible future adverse reactions.

Abstract

Background: Paclitaxel is a microtubule-stabilizing chemotherapeutic agent. Despite its widespread use, it damages healthy tissues such as skin. The goal of this study was to prove that the real impact of paclitaxel-induced skin toxicity could be underestimated because the adverse events might appear asymptomatic. Methods: Gynecological cancer patients were recruited. Skin parameters measurements were taken after three and six paclitaxel cycles. Measurements were conducted using specific probes which measure hydration, transepidermal water loss (TEWL), sebum, elasticity and firmness, erythema, roughness, smoothness, skin thickness, and desquamation levels. Further, a 3D epidermis model was incubated with paclitaxel to analyze gene and protein expression of aquaporin 3, collagen type 1, elastin, and fibronectin. Results: Paclitaxel induced alterations in the skin parameters with no visible clinical manifestations. Gynecological cancer patients under paclitaxel treatment had a decrease in hydration, TEWL, sebum, elasticity, and thickness of the skin, while erythema, roughness, and desquamation were increased. The molecular markers, related to hydration and the support of the skin layers, and analyzed in the 3D epidermis model, were decreased. Conclusions: Results suggest that paclitaxel modifies gene and protein expression of skin-related molecular markers, and impairs different physical, physiological, and biomechanical properties of the skin of cancer patients at a subclinical level.

Impact of Water Exposure and Temperature Changes on Skin Barrier Function

The frequency of hand hygiene has increased due to the COVID-19 pandemic, but there is little evidence regarding the impact of water exposure and temperature on skin. The aim of this study is to evaluate the effect of water exposure and temperature on skin barrier function in healthy individuals. A prospective observational study was conducted. Temperature, pH, transepidermal water loss (TEWL), erythema and stratum corneum hydration (SCH) were measured objectively before and after hot- and cold-water exposure and TempTest® (Microcaya TempTest, Bilbao, Spain) contact. Fifty healthy volunteers were enrolled. Hot-water exposure increased TEWL (25.75 vs. 58.58 g·h^-1·m^-2), pH (6.33 vs. 6.65) and erythema (249.45 vs. 286.34 AU). Cold-water immersion increased TEWL (25.75 vs. 34.96 g·h^-1·m^-2) and pH (6.33 vs. 6.62). TEWL (7.99 vs. 9.98 g·h^-1·m^-2) and erythema (209.07 vs. 227.79 AU) increased after being in contact with the hot region (44 °C) of the TempTest. No significant differences were found after contact with the cold region (4 °C) of the TempTest. In conclusion, long and continuous water exposure damages skin barrier function, with hot water being even more harmful. It would be advisable to use cold or lukewarm water for handwashing and avoid hot water. Knowing the proper temperature for hand washing might be an important measure to prevent flares in patients with previous inflammatory skin diseases on their hands.

Towards Optimal pH of the Skin and Topical Formulations: From the Current State of the Art to Tailored Products

Acidic pH of the skin surface has been recognized as a regulating factor for the maintenance of the stratum corneum homeostasis and barrier permeability. The most important functions of acidic pH seem to be related to the keratinocyte differentiation process, the formation and function of epidermal lipids and the corneocyte lipid envelope, the maintenance of the skin microbiome and, consequently, skin disturbances and diseases. As acknowledged extrinsic factors that affect skin pH, topically applied products could contribute to skin health maintenance via skin pH value control. The obtained knowledge on skins’ pH could be used in the formulation of more effective topical products, which would add to the development of the so-called products ‘for skin health maintenance’. There is a high level of agreement that topical products should be acidified and possess pH in the range of 4 to 6. However, formulators, dermatologists and consumers would benefit from some more precise guidance concerning favorable products pH values and the selection of cosmetic ingredients which could be responsible for acidification, together with a more extensive understanding of the mechanisms underlaying the process of skin acidification by topical products.

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.

Skin exposure to the rubber accelerator diphenylguanidine in medical gloves-An experimental study

BACKGROUND

Dermatitis caused by occupational contact allergy to rubber additives such as diphenylguanidine (DPG) in medical gloves is a hazard for healthcare workers. Both the duration of exposure to medical gloves and the number of gloves used per day vary. The use of alcoholic skin disinfectants before glove donning is mandatory.

OBJECTIVES

To assess whether skin exposure to the rubber accelerator DPG released from glove material is influenced by alcoholic hand disinfectants, time, and pH.

METHODS

With the use of ethanol washes, the amount of DPG left on the hands after wearing of gloves for 60 minutes was measured, and comparisons between hands exposed and not exposed to alcoholic disinfectant before glove donning were made. With the use of artificial sweat buffered at pH 4, 5, and 6, DPG release from the insides of gloves at different times was measured.

RESULTS

The use of alcoholic disinfectant prior to polyisoprene glove donning increased the amount of DPG recovered from the hands. Of the DPG released from polyisoprene gloves into artificial sweat, almost 84% was released within 10 minutes. pH did not influence the rate of release.

CONCLUSIONS

The use of alcoholic disinfectant increased skin exposure to the rubber accelerator DPG. Even a short duration of use of gloves results in substantial exposure to DPG.

Biophysical Measurements and Ultrasonographic Findings in Chronic Dermatitis in Comparison with Uninvolved Skin

Background:

Nowadays noninvasive techniques are performed to evaluate the biophysical properties of skin in vivo.

Aims:

The aim of this study was to evaluate the biophysical and ultrasonographic properties of skin in chronic contact or atopic dermatitis to provide better insight into pathogenesis, diagnosis, and treatment response.

Materials and Methods:

The stratum corneum hydration, transepidermal water loss (TEWL), pH, erythema, melanin, sebum, friction, temperature, elasticity parameters (R0, R2, and R5), the thickness and echo-density of epidermis, dermis, and subepidermal low-echogenic band (SLEB) were measured on lesional, perilesional, and symmetrical skin of 22 chronic dermatitis patients. The average of perilesional and symmetrical skin values (control) was compared with lesional values.

Results:

Stratum corneum hydration (P<0.001), friction (P=0.02), sebum (P=0.01), and R0 (P<0.001) were significantly lower in lesion, TEWL (P=0.03), pH (P=0.001), erythema (P=0.004), and temperature (P=0.04) were significantly higher in lesion. The thickness of epidermis (P=0.002), dermis (P=0.034), and SLEB (P<0.001) were significantly higher in lesion; and the echo-density of dermis (P<0.001) and SLEB (P<0.001) was significantly lower in lesion.

Conclusion:

Chronic contact and atopic dermatitis are characterized by certain changes in biophysical and biomechanical properties of the skin. The evaluation of these parameters might be useful in the early diagnosis and assessment of treatment response.

The immediate influence of deltamethrin on ion transport through rabbit skin. An in vitro study

Deltamethrin can be absorbed into the respiratory tract, the gastrointestinal tract and through the skin. The study was designed to assess the effect of deltamethrin on electrophysiological parameters of rabbit's skin, studied in vitro, to identify the mechanism of action and effects of short-term dermal exposure to deltamethrin. The objective of the study was to investigate changes in electrophysiological parameters after exposure to 0.01 M deltamethrin under unchanged conditions, in the presence of amiloride (sodium transport blocker) and bumetanide (chloride transport blocker). Exposure to deltamethrin reduced the electrophysiological reaction of examined tissue in unchanged conditions and during the sodium reabsorption phase but did not influence the chloride ion secretion phase. The presented data show that the pyrethroide affects transepithelial ion transport in the external layers of the skin. The inhibition of chloride and sodium ions enabled evaluation of the impact of the pesticide on dermal transport.

In vitro water resistance testing using SPF simulation based on spectroscopic analysis of rinsed sunscreens

OBJECTIVE

Water resistance retention (WRR) is the third performance attribute of sunscreens. Today, the standardized method for testing WRR is performed in vivo. For screening purposes, an in vitro method is highly preferable. Up to now, however, available methods have failed in accurately predicting in vivo WRR. In this study, we examine a novel in vitro approach aimed at enhancing in vivo prediction of WRR.

METHODS

We investigated two approaches, including a traditional procedure referred to as the 'plate method', which involves measuring in vitro sun-protection factor (SPF) before and after water immersion, and a new approach termed the 'solution method'. The latter employed a computational method to calculate the SPF using UV transmittance measurements of a sunscreen solution, obtained by rinsing the substrate without water immersion and with water immersion. It also had a model function for describing film irregularity. The aim was to avoid the effect of substrate-to-product affinity on the film distribution, which impacts the measured absolute value of the in vitro SPF occurring in the conventional approach. For both methodologies, we assessed two substrates for the sunscreen application based on different polymers, the widely used polymethylmethacrylate (PMMA) and the ethylene methacrylate acid copolymer (EMA).

RESULTS

The agreement between in vivo and in vitro WRR values obtained from each of the four test conditions was analysed using different sunscreens. No correlation was found between in vivo and in vitro WRR using the plate method, independently of the plate type. In contrast, the solution method, using EMA plates, revealed a significant correlation between in vivo and in vitro results, with an especially high correlation for in vivo non-water-resistant sunscreens. The results of two operators were comparable. The solution method was unsuitable for PMMA plates.

CONCLUSION

Despite the small discrepancy remaining between WRR values obtained from the in vitro solution method and in vivo method, which itself shows variability in results, this work provided a new insight into the in vitro testing of water resistance of sunscreens.

Skin care in nursing: A critical discussion of nursing practice and research

Skin (self-)care is part of human life from birth until death. Today many different skin care practices, preferences, traditions and routines exist in parallel. In addition, preventive and therapeutic skin care is delivered in nursing and healthcare by formal and informal caregivers. The aim of this contribution is a critical discussion about skin care in the context of professional nursing practice. An explicit skin assessment using accurate diagnostic statements is needed for clinical decision making. Special attention should be paid on high risk skin areas, which may be either too dry or too moist. From a safety perspective the protection and maintenance of skin integrity should have the highest priority. Skin cleansing is the removal of unwanted substances from the skin surface. Despite cleansing efficacy soap, other surfactants and water will inevitably always result in the destruction of the skin barrier. Thousands of products are available to hydrate, moisturize, protect and restore skin properties dependent upon their formulation and the concentration of ingredients. These products intended to left in contact with skin exhibit several actions on and in the skin interfering with skin biology. Unwanted side effects include hyper-hydration and disorganization of lipid bilayers in the stratum corneum, a dysfunctional barrier, increased susceptibility to irritants and allergies, and increases of skin surface pH. Where the skin barrier is impaired appropriate interventions, e.g. apply lipophilic products in sufficient quantity to treat dry skin or protect the skin from exposure to irritants should be provided. A key statement of this contribution is: every skin care activity matters. Every time something is placed on the skin, a functional and structural response is provoked. This response can be either desired or undesired, beneficial or harmful. The choice of all skin care interventions in nursing and healthcare practice must be based on an accurate assessment of the skin and concomitant health conditions and on a clearly defined outcome. A standardized skin care and skin care product language is needed for researchers planning and conducting clinical trials, for reviewers doing systematic reviews and evidence-base summaries, for nurses and other healthcare workers to deliver evidence-based and safe skin care.

Sunscreen formulations may serve as additional water barrier on skin surface: a clinical assessment

OBJECTIVES

Extended water exposure can cause stratum corneum swelling and a more porous skin barrier. People often wear water-resistant sunscreen formulations during extended period of water activities in the summer to protect skin from harmful UV rays. We wanted to evaluate whether sunscreen formulations can also serve as additional water barriers to help mitigate the disruption in stratum corneum caused by constant exposure to water.

METHODS

We conducted trans-epidermal water loss (TEWL) measurement in a controlled water patch (including salt and chlorine water) model and then applied this relevant model to study the effects of pre-treatments of sunscreen sprays and stick. We also conducted water sorption-desorption test in vivo with and without sunscreens. Finally, we studied the effect of constant water exposure combined with a known irritant, sodium lauryl sulphate (SLS), in a randomized clinical trial.

RESULTS

We found that application of sunscreen formulations help mitigate water-induced barrier disruption by repelling water at skin surface. Pre-treatment of sunscreen also statistically decreased the irritation in an acute patch test model.

CONCLUSIONS

Hydrophobic sunscreen formulations can help protect skin from extended water exposure by serving as additional water barriers.