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• Light transmission analysis of historical and modern commercial alum-tawed skin. • Assessing of the stability and durability of alum-tawed skin for use in restoration. • Hydrothermal stability of alum-tawed skin with respect to leather and parchment. • Durability and stability of alum-tawed skin after the artificial ageing process. • LTA as a tool for selecting the most suitable alum-tawed skin for restoration. Alum-tawed skin has been widely used in the past for the production of bookbindings elements because of its physical–mechanical properties and production process, easier and faster than that required for leather. Nevertheless, unlike for other skin-based materials employed in books production, such as parchment and leather, for alum-tawed skin the manufacturing process appears to be less standardized and rather few data are available in the literature on its durability and sensitivity to deterioration. In this work, a number of commercial samples of alum-tawed skin, from different manufactures and belonging to different animal species, were analysed by Light Transmission Analysis (LTA) to characterize their collagen hydrothermal stability, so as to gather useful information regarding their possible use for restoration works. The samples were then subjected to an artificial ageing process to assess their possible long term stability compared with that of some historical samples coming from 14th, 15th and 16th century bindings. The obtained results show that, as expected, the treatments the investigated alum-tawed skin samples undergo during the manufacture processes does not induce a level of stability of the collagen molecules higher than that of the vegetable and chrome tanning used for the leather treatment, although such treatment, in some cases, makes the alum-tawed skin slightly more stable than parchment. Moreover, accelerated ageing analysis showed that whatever the initial stability of the analysed samples, it decreases with ageing more rapidly and markedly than for parchment and leather, revealing a general lower durability of the alum-tawed skin to hydrothermal deterioration. [ABSTRACT FROM AUTHOR]

BACKGROUND: The clinical outcomes of bipolar radiofrequency (RF) lipolysis, a prevalent non-invasive fat reduction procedure, hinge on the delicate balance between effective lipolysis and patient safety, with skin overheating and subsequent tissue damage as primary concerns. OBJECTIVE: This study aimed to investigate a novel bipolar radiofrequency lipolysis technique, safeguarding the skin through an innovative PID temperature control algorithm. METHODS: Utilizing COMSOL Multiphysics simulation software, a two-dimensional fat and skin tissue model was established, simulating various PID temperature control schemes. The crux of the simulation involved a comparative analysis of different PID temperatures at 45 °C, 50 °C, and 55 °C and constant power strategies, assessing their implications on skin temperature. Concurrently, a custom bipolar radiofrequency lipolysis device was developed, with ex vivo experiments conducted using porcine tissue for empirical validation. RESULTS: The findings indicated that with PID settings of Kp = 7, Ki = 2, and Kd = 0, and skin temperature control at 45 °C or 50 °C, the innovative PID-based epidermal temperature control strategy successfully maintained the epidermal temperature within a safe range. This maintenance was achieved without compromising the effectiveness of RF lipolysis, significantly reducing the risk of thermal damage to the skin layers. CONCLUSION: Our research confirms the substantial practical utility of this advanced PID-based bipolar RF lipolysis technique in clinical aesthetic procedures, enhancing patient safety during adipose tissue ablation therapies. [ABSTRACT FROM AUTHOR]

Transparent polysiloxane elastomers with good self-healing and reprocessing abilities have attracted significant attention in the field of artificial skin and flexible displays. Herein, we propose a simple one-pot method to fabricate a room temperature self-healable polysiloxane elastomer (HPDMS) by introducing dynamic and reversible imine bonds and boroxine into polydimethylsiloxane (PDMS) networks. The presence of imine bonds and boroxine is proved by FT−IR and NMR spectra. The obtained HPDMS elastomer is highly transparent with a transmittance of up to 80%. The TGA results demonstrated that the HPDMS elastomer has good heat resistance and can be used in a wide temperature range. A lower glass transition temperature (Tg, −127.4 °C) was obtained and revealed that the elastomer is highly flexible at room temperature. Because of the reformation of dynamic reversible imine bonds and boroxine, the HPDMS elastomers exhibited excellent autonomous self-healing properties. After healing for 3 h, the self-healing efficiency of HPDMS reached 96.3% at room temperature. Moreover, the elastomers can be repeatedly reprocessed multiple times under milder conditions. This work provides a simple but effective method to prepare transparent self-healable and reprocessable polysiloxane elastomers. [ABSTRACT FROM AUTHOR]

The article presents the discussion on use of a SCOBY as artificial skin for training in other medical procedures. Topics include fermentation process, layers of cellulose are formed over each other, creating a progressively thickening membrane with a high tensile strength; and ability to be repaired and reused, and environmental benefits in using a biodegradable product.

Hollow microneedles (HMNs) are minimally invasive needle-like microfeatures usually arranged in arrays designed for drug delivery and body fluid collection in a painless manner. In a recent work, we demonstrated a novel methodology to mass produce hollow polymer microneedles at a low cost. This methodology combines ultrashort pulse laser ablation to create inverse needle shapes in moulds and replication through polymer injection moulding. For a HMN to be functional, it should effectively pierce the skin at a low force and enable fluidic passage through the skin without leakage. This study investigates the impact of different laser scanning strategies on the cavity morphology and analyses how the various geometrical characteristics of the needle influence the penetration efficacy. To assess the penetration behaviour of the replicated HMNs, a combination of agarose gel and Parafilm® is employed as an in vitro testing platform. Furthermore, a correlation between HMN geometry, penetration performance, and modification of polymer material and holding pressure during injection moulding is established. The results indicate that a certain needle length is essential for effective penetration. Moreover, minimising the tip area, a factor significantly affecting penetration force, can be achieved by increasing the eccentricity of the scan-free area and expanding the scanning diameter. However, it is important to consider other functional needle features such as the ridge height or full lumen, which come at a cost to the tip sharpness. This work highlights the multiple interactions between the scanning strategy, the injection moulding process parameters, the needle geometry, and the penetration force. This study provides insights into optimization of the HMN design and the fabrication for enhanced penetration efficacy of functional injection-moulded polymeric HMNs. [ABSTRACT FROM AUTHOR]

The rapid development of nanotechnology has offered the possibility of creating nanosystems that can be used as drug carriers. The use of such carriers offers real opportunities for the development of non-invasive drug delivery through skin structures. However, in addition to the ability to create suitable nanocarriers, it is also necessary to know how they move through dermal layers. The human skin consists of layers with different wettability characteristics, which greatly complicates how introduced substances move through it. In this work, an experimental study of the diffusion process of nanoparticles through partitions with different wettability properties was carried out. Conventional diffusion tests using Franz chambers were used for this purpose. We quantified how the wettability of the barrier, the number of layers, and their mutual configuration affect the transport of nanoparticles. Based on the results, an analysis of the phenomena taking place, depending on the wettability of the partition, was carried out. A model relationship was also proposed to determine the effective diffusion coefficient, taking into account the influence of the wettability and porosity of the barrier. [ABSTRACT FROM AUTHOR]

Wounds pose significant challenges to public health, primarily due to the loss of the mechanical integrity and barrier function of the skin and impaired angiogenesis, causing physical morbidities and psychological trauma to affect patients. Reconstructing the vasculature of the wound bed is crucial for promoting wound healing, reducing scar formation and enhancing the quality of life for patients. The development of pro‐angiogenic skin substitutes has emerged as a promising strategy to facilitate vascularization and expedite the healing process of burn wounds. This review provides an overview of the various types of skin substitutes employed in wound healing, explicitly emphasising those designed to enhance angiogenesis. Synthetic scaffolds, biological matrices and tissue‐engineered constructs incorporating stem cells and primary cells, cell‐derived extracellular vesicles (EVs), pro‐angiogenic growth factors and peptides, as well as gene therapy‐based skin substitutes are thoroughly examined. The review summarises the existing challenges, future directions and potential innovations in pro‐angiogenic dressing for skin substitutes. It highlights the need for continued research to develop new technologies and combine multiple strategies and factors, and to overcome obstacles and advance the field, ultimately leading to improved outcomes for wound patients. [ABSTRACT FROM AUTHOR]

Background/Purpose: Nowadays, there are emerging trends in customized and personalized photoprotection, focusing on the innovative approaches to enhance sun protection efficacy tailored to individual needs. Methods: We conducted an electronic search of the following databases: MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Skin Group Specialised Skin Register, and TESEO. Specific search terms related to personalized photoprotection and the variables of age, genetic predisposition, skin phototype, photodermatosis, and physiological conditions such as pregnancy, as well as lifestyle habits were used. Results/Conclusion: The article highlights the challenges and opportunities in adopting personalized photoprotection strategies, aiming to promote skin health and prevent the harmful effects of UV radiation in the era of precision medicine. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) materials can convert mechanical stimuli into visible signals for real-time visualization of stress sensing. Since stress sensing solely based on ML absolute strength is susceptible to the external environment, ratiometric ML detection approach is expected to provide stress description with improved accuracy and stability. In this study, a stress-dependent ratiometric ML is achieved using the Eu2+ and Mn2+ co-doped SrMg2(PO4)2 (SMP) phosphors, enabling color-resolved visualization of uploaded stress stimulus. Moreover, the linear relationship between the ML intensity ratio (MLIR) and the applied stress leads to an obvious variation in ML color upon different applied stress. Herein, the as-explored ML composites films as an artificial skin could provide a visualization and quantification tool for monitoring human knee motion with great accuracy and precision. [ABSTRACT FROM AUTHOR]

Currently, metal is the most common exterior material used in robot development due to the need to protect the motor. However, as soft, wearable, and humanoid robots are gradually being developed, many robot parts need to be converted into artificial skin using flexible materials. In this study, in order to develop soft exterior parts for robots, we intended to manufacture exterior robot arm parts via fused filament fabrication (FFF) 3D printing according to various structural and thickness conditions and analyze their mechanical properties. The exterior parts of the robot arms were manufactured utilizing Shore 95 A TPU (eTPU, Esun, Shenzhen, China), which is renowned for its softness and exceptional shock absorption characteristics. The exterior robot arm parts were modeled in two parts, the forearm and upper arm, by applying solid (SL) and re-entrant (RE) structures and thicknesses of 1, 2, and 4 mm. The mechanical properties were analyzed through the use of three-point bending, tensile, and compression testing. All of the characterizations were analyzed using a universal testing machine (AGS-X, SHIMADZU, Kyoto, Japan). After testing the samples, it was confirmed that the RE structure was easily bendable towards the bending curve and required less stress. In terms of the tensile tests, the results were similar to the bending tests; to achieve the maximum point, less stress was required, and for the compression tests, the RE structure was able to withstand the load compared to the SL structure. Therefore, after analyzing all three thicknesses, it was confirmed that the RE structure with a 2 mm thickness had excellent characteristics in terms of bending, tensile, and compressive properties. Therefore, the re-entrant pattern with a 2 mm thickness is more suitable for manufacturing a 3D-printed humanoid robot arm. [ABSTRACT FROM AUTHOR]

Chronic exposure to ultraviolet (UV) radiation from sunlight accelerates skin ageing, which is followed by harsh, thick, dry and loose conditions. One of the most demonstrative symptoms is deep wrinkles induced by skin barrier disruption. Our previous research showed that Phaseolus angularis seed extract (PASE) effectively inhibits skin ageing through UVB protection in HaCaT cells by suppressing skin damage. However, its efficacy has not been evaluated in clinical trials so far. PASE cream's effectiveness was initially tested on the artificial skin model, revealing an increase in filaggrin and defence against skin damage. Based on these results, in this single‐centred, randomized, double‐blind study, we investigated the anti‐ageing effect of PASE in human eye wrinkle areas. For these 21 healthy adult women aged 30 to 59, a PASE cream was applied to the right eye wrinkle area and a placebo to the left eye wrinkle area twice a day (morning and evening) for 12 weeks. The change in thick, deep crease wrinkles around the eyes was confirmed by visual evaluation, skin measurements and a questionnaire. As a result, the surface roughness (R1), maximum roughness (R2), average roughness (R3), smoothness depth (R4) and arithmetic mean roughness (R5) values in the group using the PASE cream all decreased. Particularly, R1, R4 and R5 significantly decreased by 18.1%, 18.6% and 25.0%, respectively. Subjects who applied PASE cream also experienced an improvement in skin moisture nearly twice the time compared to the placebo group. In addition, no participants reported side effects. Our study showed that PASE cream led to clinically significant levels of wrinkle improvement. In conclusion, as PASE is a natural, safe food with no side effects, it can be a good resource for natural anti‐wrinkle functional cosmetics in the future. [ABSTRACT FROM AUTHOR]

Background: Burn-related injuries are a major global health issue, causing 180,000 deaths per year. Early debridement of necrotic tissue in association with a split-thickness skin graft is usually administered for some of the 2nd- and 3rd-degree injuries. However, this approach can be complicated by factors such as a lack of proper donor sites. Artificial skin substitutes have attracted much attention for burn-related injuries. Keratinocyte sheets are one of the skin substitutes that their safety and efficacy have been reported by previous studies. Methods: Two consecutive clinical trials were designed, one of them is phase I, a non-randomized, open-label trial with 5 patients, and phase II is a randomized and open-label trial with 35 patients. A total number of 40 patients diagnosed with 2nd-degree burn injury will receive allogenic keratinocyte sheet transplantation. The safety and efficacy of allogeneic skin graft with autograft skin transplantation and conventional treatments, including Vaseline dressing and topical antibiotic, will be compared in different wounds of a single patient in phase II. After the transplantation, patients will be followed up on days 3, 7, 10, 14, 21, and 28. In the 3rd and 6th months after the transplantation scar, a wound closure assessment will be conducted based on the Vancouver Scar Scale and the Patient and Observer Scar Assessment Scale. Discussion: This study will explain the design and rationale of a cellular-based skin substitute for the first time in Iran. In addition, this work proposes this product being registered as an off-the-shelf product for burn wound management in the country. Trial registration: Iranian Registry of Clinical Trials (IRCT) IRCT20080728001031N31, 2022-04-23 for phase I and IRCT20080728001031N36, 2024-03-15 for phase II. [ABSTRACT FROM AUTHOR]

Artificial electronic skin (E‐skin), a class of promising materials mimicking the physical‐chemical and sensory performance of the human skin, has gained extensive interest in the field of human health‐monitoring and robotic skins. However, developing E‐skin simultaneously achieving high resilience, hysteresis‐free, and absent external power is always a formidable challenge. Herein, a liquid‐free eutectic gel‐based self‐powered E‐skin with high resilience, fatigue resistance, and conductivity is prepared by introducing hydroxypropyl cellulose (HPC) into metal salt‐based deep eutectic solvents (MDES). The unique structural design of cellulose‐anchored permanent entangled poly(acrylic acid) (PAA) chain, in combination with rapid broken/reconstruction of the dense dynamic sacrificial bonds, realizes the fabrication of high‐elastic E‐skin with negligible hysteresis. This further demonstrates the promising practical application of the cellulose‐based eutectogel with high transmittance (92%), high conductivity (36.6 mS m−1), and high resilience (98.1%), and excellent environment stability in robust triboelectric nanogenerator for energy harvesting and high resilience, self‐powered E‐skin for human health‐caring and human‐machine interaction. [ABSTRACT FROM AUTHOR]

It is currently unknown whether all Plasmodium falciparum-infected mosquitoes are equally infectious. We assessed sporogonic development using cultured gametocytes in the Netherlands and naturally circulating strains in Burkina Faso. We quantified the number of sporozoites expelled into artificial skin in relation to intact oocysts, ruptured oocysts, and residual salivary gland sporozoites. In laboratory conditions, higher total sporozoite burden was associated with shorter duration of sporogony (p<0.001). Overall, 53% (116/216) of infected Anopheles stephensi mosquitoes expelled sporozoites into artificial skin with a median of 136 expelled sporozoites (interquartile range [IQR], 34-501). There was a strong positive correlation between ruptured oocyst number and salivary gland sporozoite load (ρ = 0.8; p<0.0001) and a weaker positive correlation between salivary gland sporozoite load and number of sporozoites expelled (ρ = 0.35; p=0.0002). In Burkina Faso, Anopheles coluzzii mosquitoes were infected by natural gametocyte carriers. Among salivary gland sporozoite positive mosquitoes, 89% (33/37) expelled sporozoites with a median of 1035 expelled sporozoites (IQR, 171-2969). Again, we observed a strong correlation between ruptured oocyst number and salivary gland sporozoite load (ρ = 0.9; p<0.0001) and a positive correlation between salivary gland sporozoite load and the number of sporozoites expelled (ρ = 0.7; p<0.0001). Several mosquitoes expelled multiple parasite clones during probing. Whilst sporozoite expelling was regularly observed from mosquitoes with low infection burdens, our findings indicate that mosquito infection burden is positively associated with the number of expelled sporozoites. Future work is required to determine the direct implications of these findings for transmission potential. [ABSTRACT FROM AUTHOR]

Riveting quality is crucial to an aircraft's overall aerodynamic performance and fatigue life. In order to effectively extract the point cloud of rivet heads and analyze the quality of riveting, this paper proposes a rivet flushness detection method based on the normal vector-density clustering algorithm. First, initial point cloud data sampling is based on normal vectors. Then, the density clustering algorithm is employed to cluster and extract the point cloud of rivet heads. Subsequently, the obtained point cloud of rivet heads is subjected to the random sample consensus algorithm for fitting the contour and obtaining the model parameters of the rivet head. The paper introduces a quality detection metric to describe the flushness of the rivet head. Finally, the proposed method is applied to analyze the skin and theoretical model point cloud data of rivets. The results demonstrate that the proposed method yields small errors and high accuracy compared to theoretical values. The method is further employed for quality detection and analysis of rivet flushness in practical aircraft engineering. A visualization system for rivet flushness quality detection is developed to represent the results visually. This system enhances the intuitive identification of rivet detection outcomes. Therefore, the proposed method holds significant engineering application value in rivet flushness detection. [ABSTRACT FROM AUTHOR]

Introduction: Esthetic procedures are currently among the most effective options for consumers seeking to correct aging signs such as fine lines, wrinkles, and skin tone unevenness. Currently, there is a scientific need for an adjunct active to be paired with esthetic procedures to encourage wound recovery and address postprocedure pigmentation concerns. Objective: Toward that goal, this study assessed the efficacy of a peptide created from a multi‐component reaction (multi‐component peptide, MCP) as a model active for postprocedure care and evaluated its ability to promote skin healing in an ablative laser‐induced wound model on the forearm. Methods: The mechanism of action of MCP was investigated using tubo assays, 2D melanocyte, and fibroblast cultures, reconstructed skin equivalents, and ex vivo skin explants. The MCP formula and the clinical benchmark formula of Aquaphor were assessed head‐to‐head by applying the products topically in an ablative laser‐induced wound model (n = 20 subjects). The promotion of wound healing was evaluated by the investigator assessment of epithelial confluence, crusting or scabbing, general wound appearance, erythema, and edema. Results: MCP was determined to be beneficial to postprocedure skin recovery and healing by four main mechanisms of action: barrier repair as determined in an ex vivo tape‐stripping model, reduction of inflammation and postinflammatory hyperpigmentation, reduction of elastase activity, and stimulation of fibroblast through the mTOR pathway. The formula containing 10% MCP enhanced the kinetics of epithelial confluence and improvement of the crusting or scabbing appearance of the laser‐generated wounds in a laser‐induced mini‐zone wound healing study on the forearm. Conclusion: This study demonstrates the use of MCP as a proof of concept regenerative active that when incorporated into an optimized postprocedure skincare formula can improve skin healing and enhance the appearance of skin after injury with relevance to ablative aesthetic procedures. [ABSTRACT FROM AUTHOR]

Background: Current methods for evaluating efficacy of cosmetics have limitations because they cannot accurately measure changes in the dermis. Skin sampling using microneedles allows identification of skin‐type biomarkers, monitoring treatment for skin inflammatory diseases, and evaluating efficacy of anti‐aging and anti‐pigmentation products. Materials and methods: Two studies were conducted: First, 20 participants received anti‐aging treatment; second, 20 participants received anti‐pigmentation treatment. Non‐invasive devices measured skin aging (using high‐resolution 3D‐imaging in the anti‐aging study) or pigmentation (using spectrophotometry in the anti‐pigmentation study) at weeks 0 and 4, and adverse skin reactions were monitored. Skin samples were collected with biocompatible microneedle patches. Changes in expression of biomarkers for skin aging and pigmentation were analyzed using qRT‐PCR. Results: No adverse events were reported. In the anti‐aging study, after 4 weeks, skin roughness significantly improved in 17 out of 20 participants. qRT‐PCR showed significantly increased expression of skin‐aging related biomarkers: PINK1 in 16/20 participants, COL1A1 in 17/20 participants, and MSN in 16/20 participants. In the anti‐pigmentation study, after 4 weeks, skin lightness significantly improved in 16/20 participants. qRT‐PCR showed significantly increased expression of skin‐pigmentation‐related biomarkers: SOD1 in 15/20 participants and Vitamin D Receptor (VDR) in 15/20 participants. No significant change in TFAP2A was observed. Conclusion: Skin sampling and mRNA analysis for biomarkers provides a novel, objective, quantitative method for measuring changes in the dermis and evaluating the efficacy of cosmetics. This approach complements existing evaluation methods and has potential application in assessing the effectiveness of medical devices, medications, cosmeceuticals, healthy foods, and beauty devices. [ABSTRACT FROM AUTHOR]

Background: The Grand‐AID research project, consisting of GRANDEL‐The Beautyness Company, the dermatology department of Augsburg University Hospital and the Chair of IT Infrastructure for Translational Medical Research at Augsburg University, is currently researching the development of a digital skin consultation tool that uses artificial intelligence (AI) to analyze the user's skin and ultimately perform a personalized skin analysis and a customized skin care routine. Training the AI requires annotation of various skin features on facial images. The central question is whether videos are better suited than static images for assessing dynamic parameters such as wrinkles and elasticity. For this purpose, a pilot study was carried out in which the annotations on images and videos were compared. Materials and Methods: Standardized image sequences as well as a video with facial expressions were taken from 25 healthy volunteers. Four raters with dermatological expertise annotated eight features (wrinkles, redness, shine, pores, pigmentation spots, dark circles, skin sagging, and blemished skin) with a semi‐quantitative and a linear scale in a cross‐over design to evaluate differences between the image modalities and between the raters. Results: In the videos, most parameters tended to be assessed with higher scores than in the images, and in some cases significantly. Furthermore, there were significant differences between the raters. Conclusion: The present study shows significant differences between the two evaluation methods using image or video analysis. In addition, the evaluation of the skin analysis depends on subjective criteria. Therefore, when training the AI, we recommend regular training of the annotating individuals and cross‐validation of the annotation. [ABSTRACT FROM AUTHOR]

Background: Recent advancements in artificial intelligence have revolutionized dermatological diagnostics. These technologies, particularly machine learning (ML), including deep learning (DL), have shown accuracy equivalent or even superior to human experts in diagnosing skin conditions like melanoma. With the integration of ML, including DL, the development of at home skin analysis devices has become feasible. To this end, we introduced the Skinly system, a handheld device capable of evaluating various personal skin characteristics noninvasively. Materials and Methods: Equipped with a moisture sensor and a multi‐light‐source camera, Skinly can assess age‐related skin parameters and specific skin properties. Utilizing state‐of‐the‐art DL, Skinly processed vast amounts of images efficiently. The Skinly system's efficacy was validated both in the lab and at home, comparing its results to established "gold standard" methods. Results: Our findings revealed that the Skinly device can accurately measure age‐associated parameters, that is, facial age, skin evenness, and wrinkles. Furthermore, Skinly produced data consistent with established devices for parameters like glossiness, skin tone, redness, and porphyrin levels. A separate study was conducted to evaluate the effects of two moisturizing formulations on skin hydration in laboratory studies with standard instrumentation and at home with Skinly. Conclusion: Thanks to its capability for multi‐parameter measurements, the Skinly device, combined with its smartphone application, holds the potential to replace more expensive, time‐consuming diagnostic tools. Collectively, the Skinly device opens new avenues in dermatological research, offering a reliable, versatile tool for comprehensive skin analysis. [ABSTRACT FROM AUTHOR]

Traditional artificial skin gels often only focuses on a single perspective and overlooks the necessity of multidimensional synergistic design for sensitivity enhancement. To address these problems, the innovative introduction of dual solvents on the surface of polyacrylamide/sodium alginate gel induces to the transformation of supramolecular interactions including ion coordination, crystalline alcohol, and phase separation, synergistically achieving adjustable wrinkle wavelengths (304.2 ± 19.9 to 2393.5 ± 95.9 µm) and modulated chemical compositions with tunable moduli (87.5 ± 3.3 to 157.6 ± 3.7 kPa). This flexible strategy allows the construction of long‐range ordered wrinkled microstructures of three‐dimensional surfaces and complex morphologies. Meanwhile, the bridge effect induced by crystalline alcohols directs the insertion of ethanol molecules into the polymer chains, effectively reducing intramolecular friction. Benefiting from the small wavelength and low modulus dominated by crystalline alcohol, the wrinkled gel exhibits extremely high sensitivity of 164 kPa−1 (<0.5 kPa) and wide detection range (44.3 kPa). The wrinkled gel remains stable high sensitive to detect micro‐ and large stress, tactile perception, and human motion behaviors. This work proposes a new strategy for constructing highly sensitive bioinspired skin from multiple dimensions, showing broad application prospects in the fields of bioengineering and behavioral cognition. [ABSTRACT FROM AUTHOR]

The article focuses on the evolution of cellular, acellular, and matrix-like products (CAMPs) used in wound care, highlighting their diverse categorization and regulatory pathways. Topics discussed include the terminology changes from "skin substitutes" to CAMPs, regulatory pathways for CAMPs, and their classification based on composition and application in wound management.

Perspiration is an important physiological process that maintains thermal homeostasis and water–salt balance. However, the collection and analysis of perspiration currently rely on microfluidic technology and colorimetric assays. The complexity and high cost of fabricating microfluidic channels and the insecurity of chemical reagents for color reactions should be optimized. In this work, a colorimetry electronic skin (e‐skin) for intelligent perspiration monitoring has been realized. The colorimetry e‐skin system consists of the polyurethane (PU) nanomesh and the object detection algorithm You Only Look Once version 3 (YOLOv3). Due to the 44% porosity of the PU nanomesh and capillary action, the low‐cost PU nanomesh (<1 cent) can be used as the colorimetric indicator. The volume of the PU nanomesh expands to 362.37% as a result of perspiration being absorbed and changes the optical transmittance (up to 277.78%). A finite element model based on capillary action has been proposed to explain the change in optical transmittance. Finally, a database containing 735 images has been built, and the object detection algorithm YOLOv3 is used to analyze the perspiration absorbed by the PU nanomesh. The detection results can identify the perspiration volume with a high accuracy of 97%. These results show that this work has great potential in healthcare field. [ABSTRACT FROM AUTHOR]

The Industry 5.0 paradigm has a human-centered vision of the industrial scenario and foresees a close collaboration between humans and robots. Industrial manufacturing environments must be easily adaptable to different task requirements, possibly taking into account the ergonomics and production line flexibility. Therefore, external sensing infrastructures such as cameras and motion capture systems may not be sufficient or suitable as they limit the shop floor reconfigurability and increase setup costs. In this paper, we present the technological advancements leading to the realization of ProxySKIN, a skin-like sensory system based on networks of distributed proximity sensors and tactile sensors. This technology is designed to cover large areas of the robot body and to provide a comprehensive perception of the surrounding space. ProxySKIN architecture is built on top of CySkin, a flexible artificial skin conceived to provide robots with the sense of touch, and arrays of Time-of-Flight (ToF) sensors. We provide a characterization of the arrays of proximity sensors and we motivate the design choices that lead to ProxySKIN, analyzing the effects of light interference on a ToF, due to the activity of other sensing devices. The obtained results show that a large number of proximity sensors can be embedded in our distributed sensing architecture and incorporated onto the body of a robotic platform, opening new scenarios for complex applications. [ABSTRACT FROM AUTHOR]

Human skin comprises multiple hierarchical layers that perform various functions such as protection, sensing, and structural support. Developing electronic skin (E‐skin) with similar properties has broad implications in health monitoring, prosthetics, and soft robotics. While previous efforts have predominantly concentrated on sensory capabilities, this study introduces a hierarchical polymer system that not only structurally resembles the epidermis‐dermis bilayer structure of skin but also encompasses sensing functions. The system comprises a polymeric hydrogel, representing the "dermis", and a superimposed nanoporous polymer film, forming the "epidermis". Within the film, interconnected nanoparticles mimic the arrangement of interlocked corneocytes within the epidermis. The fabrication process employs a robust in situ interfacial precipitation polymerization of specific water‐soluble monomers that become insoluble during polymerization. This process yields a hybrid layer establishing a durable interface between the film and hydrogel. Beyond the structural mimicry, this hierarchical structure offers functionalities resembling human skin, which includes (1) water loss protection of hydrogel by tailoring the hydrophobicity of the upper polymer film; (2) tactile sensing capability via self‐powered triboelectric nanogenerators; (3) built‐in gold nanowire‐based resistive sensor toward temperature and pressure sensing. This hierarchical polymeric approach represents a potent strategy to replicate both the structure and functions of human skin in synthetic designs. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF) is a biodegradable protein and possesses superior skin‐friendliness, biocompatibility, low immunogenicity, and non‐toxicity. However, SF has a series of drawbacks. For example, the application of SF in water filtration is limited by its inadequate ability to adsorb heavy metal ions. It is not inherently antibacterial, making SF ineffective as a filter to eliminate airborne bacteria. SF without conductivity is not suitable for use in sensors and triboelectric nanogenerators. In tissue engineering, deficient mechanical and anti‐inflammatory properties also have an influence on the rate of wound recovery. While physical and chemical modifications will improve its application properties as well as broaden its application areas. This review describes the modification of SF by filling, blending, structural adjustment, post treatment, crosslinking, grafting, and in situ polymerization to provide it with other functional properties. Modified SF fibers prepared by various methods (e.g., wet/dry/microfluidic spinning, electrospinning) are discussed, and they can be used in water/air filtration, chemical/pressure/strain sensors, triboelectric nanogenerators, artificial skin, wound dressings, and tissue scaffolds. Finally, the development trend of the modified SF fibers is prospected. This review has a reference significance on how to use modified SF fibers to improve filtration efficiency, sensor performance, and wound recovery. [ABSTRACT FROM AUTHOR]

As stretchable conductive materials, ionogels have gained increasing attention. However, it still remains crucial to integrate multiple functions including mechanically robust, room temperature self‐healing capacity, facile processing, and recyclability into an ionogel‐based device with high potential for applications such as soft robots, electronic skins, and wearable electronics. Herein, inspired by the structure of spider silk, a multilevel hydrogen bonding strategy to effectively produce multi‐functional ionogels is proposed with a combination of the desirable properties. The ionogels are synthesized based on N‐isopropylacrylamide (NIPAM), N, N‐dimethylacrylamide (DMA), and ionic liquids (ILs) 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMI][TFSI]). The synergistic hydrogen bonding interactions between PNIPAM chains, PDMA chains, and ILs endow the ionogels with improved mechanical strength along with fast self‐healing ability at ambient conditions. Furthermore, the synthesized ionogels show great capability for the continuous fabrication of the ionogel‐based fibers using the melt‐spinning process. The ionogel fibers exhibit spider‐silk‐like features with hysteresis behavior, indicating their excellent energy dissipation performance. Moreover, an interwoven network of ionogel fibers with strain and thermal sensing performance can accurately sense the location of objects. In addition, the ionogels show great recyclability and processability into different shapes using 3D printing. This work provides a new strategy to design superior ionogels for diverse applications. [ABSTRACT FROM AUTHOR]

Background: Chemically induced skin sensitization, or allergic contact dermatitis, is a common occupational and public health issue. Regulatory authorities require an assessment of potential to cause skin sensitization for many chemical products. Defined approaches for skin sensitization (DASS) identify potential chemical skin sensitizers by integrating data from multiple non-animal tests based on human cells, molecular targets, and computational model predictions using standardized data interpretation procedures. While several DASS are internationally accepted by regulatory agencies, the data interpretation procedures vary in logical complexity, and manual application can be time-consuming or prone to error. Results: We developed the DASS App, an open-source web application, to facilitate user application of three regulatory testing strategies for skin sensitization assessment: the Two-out-of-Three (2o3), the Integrated Testing Strategy (ITS), and the Key Event 3/1 Sequential Testing Strategy (KE 3/1 STS) without the need for software downloads or computational expertise. The application supports upload and analysis of user-provided data, includes steps to identify inconsistencies and formatting issues, and provides predictions in a downloadable format. Conclusion: This open-access web-based implementation of internationally harmonized regulatory guidelines for an important public health endpoint is designed to support broad user uptake and consistent, reproducible application. The DASS App is freely accessible via https://ntp.niehs.nih.gov/go/952311 and all scripts are available on GitHub (https://github.com/NIEHS/DASS). [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is one of the most common microorganisms causing infections of severe skin wounds. Antibiotic or antiseptic treatments are crucial to prevent and curb these infections. Antiseptics have been reported to be cytotoxic to skin cells and few studies evaluate the impact of commonly used antibiotics. This study evaluates how clinical antibiotics affect skin cells' viability, proliferation, migration, and cytokine secretion and defines the highest non-cytotoxic concentrations that maintain antibacterial activity. Cell proliferation, viability, and migration were evaluated on cell monolayers. Cytokines related to the wound healing process were determined. The minimum inhibitory concentrations and the impact on bacterial biofilm were assessed. Results showed that 0.02 mg/mL ciprofloxacin and 1 mg/mL meropenem are the highest non-cytotoxic concentrations for fibroblasts and keratinocytes while 1.25 mg/mL amikacin and 0.034 mg/mL colistin do not affect fibroblasts' viability and cytokine secretion but have an impact on keratinocytes. These concentrations are above the minimum inhibitory concentration but only amikacin could eradicate the biofilm. For the other antibiotics, cytotoxic concentrations are needed to eradicate the biofilm. Combinations with colistin at non-cytotoxic concentrations effectively eliminate the biofilm. These results provide information about the concentrations required when administering topical antibiotic treatments on skin lesions, and how these antibiotics affect wound management therapies. This study set the basis for the development of novel antibacterial wound healing strategies such as antibiotic artificial skin substitutes. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Skin barrier dysfunction is the initial step in the development of AD. Recently, exosomes have been considered as potential cell‐free medicine for skin defects such as aging, psoriasis and wounds. The aim of this study was to investigate the effects of human dermal fibroblast‐neonatal‐derived exosome (HDFn‐Ex) on AD. HDFn‐Ex increased the expression of peroxisome proliferator activated receptor α (PPARα) and alleviated the 1‐chloro‐2,4‐dinitrobenzene (DNCB)‐mediated downregulation of filaggrin, involucrin, loricrin, hyaluronic acid synthase 1 (HAS1) and HAS2 in human keratinocyte HaCaT cells. However, these effects were inhibited by the PPARα antagonist GW6471. In the artificial skin model, HDFn‐Ex significantly inhibited DNCB‐induced epidermal hyperplasia and the decrease in filaggrin and HAS1 levels via a PPARα. In the DNCB‐induced AD‐like mouse model, HDFn‐Ex administration reduced epidermis thickening and mast cell infiltration into the dermis compared to DNCB treatment. Moreover, the decreases in PPARα, filaggrin and HAS1 expression, as well as the increases in IgE and IL4 levels induced by DNCB treatment were reversed by HDFn‐Ex. These effects were blocked by pre‐treatment with GW6471. Furthermore, HDFn‐Ex exhibited an anti‐inflammatory effect by inhibiting the DNCB‐induced increases in IκBα phosphorylation and TNF‐α expression. Collectively, HDFn‐Ex exhibited a protective effect on AD. Notably, these effects were regulated by PPARα. Based on our results, we suggest that HDFn‐Ex is a potential candidate for treating AD by recovering skin barrier dysfunction and exhibiting anti‐inflammatory activity. [ABSTRACT FROM AUTHOR]

Flexible transparent conductive electrodes (FTCEs) constitute an indispensable component in state‐of‐the‐art electronic devices, such as wearable flexible sensors, flexible displays, artificial skin, and biomedical devices, etc. This review paper offers a comprehensive overview of the fabrication techniques, growth modes, material dimensions, design, and their impacts on FTCEs fabrication. The growth modes, such as the "Stranski–Krastanov growth," "Frank–van der Merwe growth," and "Volmer–Weber growth" modes provide flexibility in fabricating FTCEs. Application of different materials including 0D, 1D, 2D, polymer composites, conductive oxides, and hybrid materials in FTCE fabrication, emphasizing their suitability in flexible devices are discussed. This review also delves into the design strategies of FTCEs, including microgrids, nanotroughs, nanomesh, nanowires network, and "kirigami"‐inspired patterns, etc. The pros and cons associated with these materials and designs are also addressed appropriately. Considerations such as trade‐offs between electrical conductivity and optical transparency or "figure of merit (FoM)," "strain engineering," "work function," and "haze" are also discussed briefly. Finally, this review outlines the challenges and opportunities in the current and future development of FTCEs for flexible electronics, including the improved trade‐offs between optoelectronic parameters, novel materials development, mechanical stability, reproducibility, scalability, and durability enhancement, safety, biocompatibility, etc. [ABSTRACT FROM AUTHOR]

Introduction: Conducting clinical research on treatments for emerging infectious diseases is often complicated by methodological challenges, such as the identification of appropriate outcome measures to assess treatment response and the lack of validated instruments available to measure patient outcomes. In bubonic plague, some studies have assessed bubo size as an indicator of treatment success, a measure widely assumed to be indicative of recovery. Evaluating this outcome however is challenging as there is no validated method for measuring bubo size. The aim of this study is to assess the accuracy and inter- and intra-rater agreement of artificial bubo measurements using a digital calliper to understand whether a calliper is an appropriate measurement instrument to assess this outcome. Methods: Study technicians measured 14 artificial buboes made from silicone overlaid with artificial silicone skin sheets over the course of two training sessions. Each artificial bubo was measured by each study technician once per training session, following a Standard Operating Procedure. The objectives of this study are to (i) evaluate the accuracy of individual measurements against the true size of the artificial bubo when using a digital calliper, (ii) understand whether the characteristics of the artificial bubo influence measurement accuracy and (iii) evaluate inter- and intra-rater measurement agreement. Results: In total, 14 artificial buboes ranging from 52.7 to 121.6 mm in size were measured by 57 raters, generating 698 measurements recorded across two training sessions. Raters generally over-estimated the size of the artificial bubo. The median percentage difference between the measured and actual bubo size was 13%. Measurement accuracy and intra-rater agreement decreased as the size of the bubo decreased. Three quarters of all measurements had a maximum of 25% difference from another measurement of the same artificial bubo. Inter-rater agreement did not vary with density, size or presence of oedema of the artificial bubo. Conclusions: The results of this study demonstrate the challenges for both individual and multiple raters to repeatedly generate consistent and accurate measurements of the same artificial buboes with a digital calliper. [ABSTRACT FROM AUTHOR]

Supramolecular polymer hydrogels, exhibiting wide applications in flexible sensing, wearable electronics, artificial skin, etc., often require complex molecule and component design to adapt extreme environments. Most supramolecular polymer hydrogels currently, however, are unable to satisfy the harsh demands ascribed to their poor mechanical properties and chemical stability. Herein, this study demonstrates a novel strategy to fabricate superstrong polyvinyl alcohol (PVA) hydrogels with densely supramolecular polymer networks (SPNs) and complexation, induced by simple deprotonation and reconfiguration of ion clusters (ICs). Such strategy enables the PVA hydrogels with high strength (9.64 ± 0.5 MPa), compressibility, and recoverability (load objects over ≈10000 times more than its weight), resistance to various solvents, freezing tolerance (keep flexible and conductive even at −50 °C) and many other performances. Notably, the properties of resultant hydrogels surpass majority reported, tackling a long‐standing dilemma both mechanical properties and stability for PVA hydrogels. A proof‐of‐concept spider robot is assembled by 3D printed model, which achieves successfully signal acquisition in different extreme conditions. In this study the multifunctional PVA hydrogels are envisioned as a simple and universal strategy for sensors in various conditions, which is significant for the exploration in extreme environments that are not easily accessible to humans, such as the North and South Poles and solvent leakage area. [ABSTRACT FROM AUTHOR]

Objective: The mechanical condition and tactile evaluation of skin are essential for the development of skin care products. Most of the existing commercial instruments and studies aim to evaluate the skin surface by pressing it for hardness or by using imaging sensors, but there have been few instrumental measurements employing rubbing motion. Here, we have developed a sensor specialized for tactile sensation and the contact phenomenon during skin rubbing. Methods: The developed sensor has three features: It can measure body parts including cheeks and arms, automate the rubbing motion of the probe and measure vibration and friction simultaneously. It is hand‐held, with metal probes that rub the skin surface while rotating under a motor drive; it has an accelerometer and a force sensor beneath the probe measuring vibration and friction forces. To evaluate the validity of the sensor's measurements, artificial skin models were measured using the developed sensor and commercially available sensors and the results were compared. The relationship between the sensor output, surface roughness measurement and sensory evaluation was also investigated. Additionally, we evaluated the inter‐rater reliability when measuring actual skin. Results: The measurements of five artificial skin models with different surface shapes showed a high correlation (r = 0.99) between the vibration intensity values evaluated by the developed sensor and those measured by a tri‐axial acceleration sensor attached to a fingernail. The correlation coefficient between the vibration intensity values and surface roughness was r = 0.91, and the correlation with the sensory evaluation score of roughness was r = 0.99. The friction coefficients measured by the developed sensor and the force plate had r = 0.93, based on measurements of five artificial skin models with different friction conditions. The inter‐rater correlation coefficients between the three participants of the developed sensor were as high as 0.92 and 0.94 for the vibration and friction measurements respectively. Conclusion: The vibration intensities and friction coefficients from the sensor were highly correlated with those of the conventional sensor. The inter‐rater reliability was also high. The developed sensor can be useful for tactile evaluation in skin‐care product development. [ABSTRACT FROM AUTHOR]

Organic semiconductor materials featuring lightweight, and flexibility may play a significant role in various future applications, such as foldable displays, wearable devices, and artificial skin. For developing high-performance organic devices, organic crystals are highly desired, while a remaining fundamental issue is their contact problem. Here, we have grown a high-quality rubrene single crystal by utilizing a simple in-air sublimation technique. The contact characteristics (barrier height and contact resistance) are detail-studied by resist-free transfer electrodes (Au metal or graphene/Au). The Schottky barrier of the rubrene/graphene interface is lower and can be also modulated by gate bias, which is confirmed by spatial photocurrent mapping. Finally, we demonstrated the zero-bias photocurrent imaging application by constructing the asymmetrical device employing different electrode contacts. Our work would be of significance for studying the contact issue of organic crystals and wireless imaging. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the antimicrobial activity of Stachys rupestris essential oil and inactivation of the pathogens on lab-made skin the oil in the fight against Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Candida tropicalis. S. rupestris EO was extracted by hydrodistillation, and its contents were analyzed by GCMS. Logarithmic reduction of the pathogens inoculated on the artificial skin surface by S. rupestris EO was studied for the first time. The highest inhibition zone was 22.1 mm on C. tropicalis, while the lowest IZ was 0.1 mm on E. coli. The other zones were 20.01 mm for Acinetobacter baumannii, 20.02 mm for Enterococcus faecalis, 20.01 mm for Staphylococcus aureus, 22.03 for Candida albicans (p < 0.05). As a result, S. rupestris essential oil was effective on most of the microorganisms and might be increased to use in the treatment of skin infections in the future. [ABSTRACT FROM AUTHOR]

Skin damage resulting from burns, injuries, or diseases can lead to significant functional and esthetic deficits. However, traditional treatments, such as skin grafting, have limitations including limited donor skin availability, poor aesthetics, and functional impairment. Skin tissue engineering provides a promising alternative, with engineered artificial skins offering a highly viable avenue. Engineered artificial skin is designed to mimic or replace the functions of natural human skin and find applications in various medical treatments, particularly for severe burns, chronic wounds, and other skin injuries or defects. These artificial skins aim to promote wound healing, provide temporary coverage, permanent skin replacement, and restore the skin's barrier function. Artificial skins have diverse applications in medicine and wound care, addressing burns, chronic wounds, and traumatic injuries. They also serve as valuable tools for research in tissue engineering, offering experimental models for studying wound healing mechanisms, testing new biomaterials, and exploring innovative approaches to skin regeneration. This review provides an overview of current construction strategies for engineered artificial skin, including cell sources, biomaterials, and construction techniques. It further explores the primary application areas and future prospects of artificial skin, highlighting their potential to revolutionize skin reconstruction and advance the field of regenerative medicine. [ABSTRACT FROM AUTHOR]

3D printing technology, as a flexible and efficient manufacturing method, provides new possibilities for preparing flexible tactile sensors. This paper reviews the preparation results of flexible tactile sensors based on 3D printing technology. Three types of 3D printing technology commonly used in preparing flexible tactile sensors are first described: photopolymerization, material extrusion, and electrohydrodynamic. Under the process corresponding to each type, suitable printing materials are discussed, and their applications in flexible tactile sensors preparation are explored. On this basis, the effects of these three types of processes and printing materials on the performance of flexible tactile sensors and the related application progress are analyzed. Finally, the challenges and opportunities of flexible tactile sensors based on 3D printing technology are summarized, and the future development trend is prospected. [ABSTRACT FROM AUTHOR]

The conformal integration of the electronic skin on the non‐developable surface is in great demand for the comprehensive tactile sensing of robotics and prosthetics. However, the current techniques still encounter obstacles in achieving conformal integration of film‐like electronic skin on non‐developable surfaces with substantial curvatures for contact pressure detection and tactile mapping. In this paper, by utilizing the 3D printing technology to prepare the 3D electrode array in the structural component following its surface curvature, and covering it with a molded functional shell to form the pressure sensitive iontronic interface, a device is proposed to achieve high‐sensitive pressure detection and high‐fidelity tactile mapping on a complicated non‐developable surface, called structural electronic skin (SES). The SES is prepared in a 3D printed fingertip with 46 tactile sensing units distributed on its curved surface, achieving the integration of both structural and tactile functions in a single component. By integrating the smart fingertip into a dexterous hand, a series of demonstrations are presented to show the dead‐zone free pressure detection and tactile mapping with high sensitivity, for instance, 2D pulse wave monitoring and robotic injection in a medical robot, object recognition and compliant control in a smart prosthesis. [ABSTRACT FROM AUTHOR]

At a crime scene, investigators are faced with a multitude of traces. Among them, biological traces are of primary interest for the rapid genetic-based identification of individuals. "Touch DNA" consists of invisible biological traces left by the simple contact of a person's skin with objects. To date, these traces remain undetectable with the current methods available in the field. This study proposes a proof-of-concept for the original detection of touch DNA by targeting cell-derived fragments in addition to DNA. More specifically, adhesive-structure proteins (laminin, keratin) as well as carbohydrate patterns (mannose, galactose) have been detected with keratinocyte cells derived from a skin and fingermark touch-DNA model over two months in outdoor conditions. Better still, this combinatory detection strategy is compatible with DNA profiling. This proof-of-concept work paves the way for the optimization of tools that can detect touch DNA, which remains a real challenge in helping investigators and the delivery of justice. [ABSTRACT FROM AUTHOR]

The aim of this study was to provide a beneficial treatment effect of novel chitosan bio-polymeric material enriched with mesenchymal stem cell products derived from the canine adipose tissue (AT-MSC) on the artificial skin defect in a rabbit model. For the objectivity of the regeneration evaluation, we used histological analysis and a scoring system created by us, taking into account all the attributes of regeneration, such as inflammatory reaction, necrosis, granulation, formation of individual skin layers and hair follicles. We observed an acceleration and improvement in the healing of an artificially created skin defect after eight and ten weeks in comparison with negative control (spontaneous healing without biomaterial). Moreover, we were able to described hair follicles and epidermis layer in histological skin samples treated with a chitosan-based biomaterial on the eighth week after grafting. [ABSTRACT FROM AUTHOR]

A previously developed fibrin‐agarose skin model—UGRSKIN—showed promising clinical results in severely burnt patients. To determine the histological parameters associated to the biocompatibility and therapeutic effects of this model, we carried out a comprehensive structural and ultrastructural study of UGRSKIN grafted in severely burnt patients after 3 months of follow‐up. The grafted epidermis was analogue to native human skin from day 30th onward, revealing well‐structured strata with well‐differentiated keratinocytes expressing CK5, CK8, CK10, claudin, plakoglobin, filaggrin, and involucrin in a similar way to controls, suggesting that the epidermis was able to mature and differentiate very early. Melanocytes and Langerhans cells were found from day 30th onward, together with a basement membrane, abundant hemidesmosomes and lack of rete ridges. At the dermal layer, we found an interface between the grafted skin and the host tissue at day 30th, which tended to disappear with time. The grafted superficial dermis showed a progressive increase in properly‐oriented collagen fibers, elastic fibers and proteoglycans, including decorin, similarly to control dermis at day 60‐90th of in vivo follow‐up. Blood vessels determined by CD31 and SMA expression were more abundant in grafted skin than controls, whereas lymphatic vessels were more abundant at day 90th. These results contribute to shed light on the histological parameters associated to biocompatibility and therapeutic effect of the UGRSKIN model grafted in patients and demonstrate that the bioengineered skin grafted in patients is able to mature and differentiate very early at the epithelial level and after 60–90 days at the dermal level. [ABSTRACT FROM AUTHOR]

Human skin equivalents (HSEs) are three‐dimensional skin organ culture models raised in vitro. This review gives an overview of common techniques for setting up HSEs. The HSE consists of an artificial dermis and epidermis. 3T3‐J2 murine fibroblasts, purchased human fibroblasts or freshly isolated and cultured fibroblasts, together with other components, for example, collagen type I, are used to build the scaffold. Freshly isolated and cultured keratinocytes are seeded on top. It is possible to add other cell types, for example, melanocytes, to the HSE—depending on the research question. After several days and further steps, the 3D skin can be harvested. Additionally, we show possible markers and techniques for evaluation of artificial skin. Furthermore, we provide a comparison of HSEs to human skin organ culture, a model which employs human donor skin. We outline advantages and limitations of both models and discuss future perspectives in using HSEs. [ABSTRACT FROM AUTHOR]

Polydeoxyribonucleotide (PDRN) has the ability to regenerate skin cells and improve the skin barrier and wound healing. This study investigated the possibility of replacing animal-derived PDRN with plant-derived PDRN. To test this, the adventitious roots of Korean ginseng (Panax ginseng C.A. Meyer), which is commonly used to treat various diseases, were suspension-cultivated through tissue culture; subsequently, PDRN was purified using microfluidization, an ultra-high-pressure physical grinding method. The results showed that purified Panax PDRN was effective in healing skin wounds and enhancing the skin barrier. Panax PDRN promoted the proliferation of keratinocytes and fibroblasts by increasing the expression of fibronectin, filaggrin, Ki-67, Bcl-2, inhibin beta A, and Cyclin D1. It also acted as an agonist of the adenosine A2A receptor and induced the phosphorylation of focal adhesion kinase, adenosine triphosphate-dependent tyrosine kinase, and mitogen-activated protein kinase. This activated signal transduction, thereby regenerating skin cells and strengthening the barrier. These results were not only observed in skin cells but also in an artificial skin model (KeraSkinTM). The use of plant-derived PDRN instead of animal-derived PDRN can promote animal welfare and environmental sustainability. Furthermore, Panax PDRN can potentially be a new plant-derived PDRN (PhytoPDRN) that may be utilized in the treatment of various skin diseases. [ABSTRACT FROM AUTHOR]

Introduction The 2020 Nagorno-Karabakh war was an armed conflict between Azerbaijan and Armenia over an ethnically and historically significant region. This manuscript is a report on the forward deployment of acellular fish skin graft (FSG) from Kerecis™, a biologic, acellular matrix derived from the skin of wild-caught Atlantic cod that contains intact epidermis and dermis layers. The usual intention of treatment under adverse circumstances is to temporize wounds until better treatment can be attained, although ideally, rapid coverage and treatment are necessary to prevent long-term complications and loss of life and limb. An austere environment, such as the one experienced during the conflict described here, presents considerable logistical barriers for the treatment of wounded soldiers. Materials and Methods Dr H. Kjartansson from Iceland and Dr S. Jeffery from the United Kingdom traveled to Yerevan, near the heart of the conflict, to deliver and train on using FSG in wound management. The primary goal was to use FSG in patients where stabilization and improvement in the wound bed were needed before skin grafting. Other goals were to improve healing time, achieve earlier skin grafting, and have better cosmetic outcomes upon healing. Results Over the course of two trips, several patients were managed with fish skin. Injuries included large-area full-thickness burn and blast injuries. Management with FSG induced wound granulation several days sooner in all cases, and even weeks in some instances, allowing a stepdown in the reconstruction ladder with earlier skin grafting procedures and a reduction in requirement of flap surgery. Conclusions This manuscript describes a successful first instance of forward deployment of FSGs to an austere environment. FSG, in this military context, has shown great portability, with easy transfer of knowledge. More importantly, management with fish skin has shown faster granulation rates in burn wounds for skin grafting, resulting in improved patient outcomes with no documented infections. [ABSTRACT FROM AUTHOR]

At a crime scene, investigators are faced with a multitude of traces. Among them, biological traces are of primary interest for the rapid genetic-based identification of individuals. "Touch DNA" consists of invisible biological traces left by the simple contact of a person's skin with objects. To date, these traces remain undetectable with the current methods available in the field. This study proposes a proof-of-concept for the original detection of touch DNA by targeting cell-derived fragments in addition to DNA. More specifically, adhesive-structure proteins (laminin, keratin) as well as carbohydrate patterns (mannose, galactose) have been detected with keratinocyte cells derived from a skin and fingermark touch-DNA model over two months in outdoor conditions. Better still, this combinatory detection strategy is compatible with DNA profiling. This proof-of-concept work paves the way for the optimization of tools that can detect touch DNA, which remains a real challenge in helping investigators and the delivery of justice. [ABSTRACT FROM AUTHOR]

Ionic crosslinking of bromobutyl rubber (BIIR) composites was prepared using butylimidazole (IM) and ionic liquid (IL), combined with carbon nanotubes (CNT) and conductive carbon black (CCB) to enhance the intrinsic properties and heal ability of the resulting composites. Variation in the BIIR/CNT-CCB/IM/IL ratios was investigated to determine the appropriate formulation for healing the composites. Results showed that the mechanical properties were increased until the IM:IL:CNT/CCB ratio reached 1:1:1/1.5, corresponding to the optimal concentration of 5:5:5/7.5 phr. Thermo-oxidative degradation, as indicated using temperature scanning stress relaxation (TSSR), demonstrated the decomposition of the composites at higher temperatures, highlighting the superior resistance provided by the proper formulation of BIIR composites. Additionally, the conditions for the healing procedure were examined by applying pressure, temperature, and time. It was observed that the composites exhibited good elasticity at 0 °C and 60 °C, with a high rate of re-crosslinking achieved under appropriate pressure and temperature conditions. This research aims to develop a formulation suitable for the tire tread and inner liner of commercial car tires together with artificial skin products. [ABSTRACT FROM AUTHOR]

Cleansing is an important human ritual practised for hygiene, well‐being and relaxation over centuries. As part of body care it is often taken for granted, yet its relevance cannot be underestimated. Although cleansing the skin may seem trivial to some, it is accepted, that this fundamental function of skin cleansing products is highly complex, diverse and crucial for a variety of reasons in the personal, public, healthcare and dermatological settings. Employing a comprehensive and strategic approach in viewing cleansing and its rituals, supports innovation, understanding and development. Apart from being a fundamental function, as far as we know, there is no comprehensive presentation of skin cleansing with all its effects besides 'removing dirt'. To our knowledge, comprehensive analyses on the multi‐dimensional facets of skin cleansing are either rare or not published. Against this background, we examine the importance of cleansing in terms of function, relevance and concepts. First, the key functions and efficacies of skin cleansing were investigated by literature research. Based on this survey, the functions were analysed, sorted and merged and a novel approach to skin cleansing 'dimensions' was developed. Herewith, we took into consideration the evolution of skin cleansing in terms of concept evolution, complexity and testing methods for cleansing products and their claims. Several multi‐dimensional functions of skin cleansing were identified and then established into five skin cleansing dimensions, namely: hygienic and medical importance; socio‐cultural and interpersonal relevance; mood, emotion and well‐being; cosmetic and aesthetic function; corneobiological interactions. It became obvious, that these five dimensions with their corresponding 11 sub‐dimensions, are influenced by each other throughout history by culture and society, technical progress, scientific knowledge and consumer trends. This article presents the enormous complexity of skin cleansing. Skin cleansing has evolved from basic care up to a highly complex and diverse cosmetic product category in terms of technology, efficacy and usage routine(s). In view of future challenges, such as the effects of climate and associated lifestyle changes, the development of skin cleansing will remain an exciting and important topic and thus will finally, again, further increase the complexity of skin cleansing itself. [ABSTRACT FROM AUTHOR]

Recently, artificial skin has been widely used to evaluate the biochemical safety and efficacy of certain drugs. Macrophages play a crucial role in the skin immune response by interacting with fibroblasts and keratinocytes. Transcriptional analysis is a cost-effective method to assess the immune response of macrophages in artificial skin. However, high variability in the mRNA levels of inflammatory factors increases the difficulty of evaluating their immunity against biochemicals. In this study, three-dimensional (3D) artificial skin models were identified to be more sensitive to inflammatory transcription levels than two-dimensional (2D) cultures during the interactions of macrophages, fibroblasts, and keratinocytes. Lipopolysaccharides significantly increased the interleukin (IL)-1β and IL-6 levels in 3D fibroblasts/keratinocytes than in 2D culture. They also significantly upregulated IL-1β, IL-6, IL-23, and tumor necrosis factor-α levels in the 3D macrophage/fibroblast/keratinocyte model. In addition, the macrophage-containing 3D skin was evaluated as a promising model for inflammatory transcriptional analysis via in vitro psoriasis studies using imiquimod. [ABSTRACT FROM AUTHOR]

[Display omitted] Our previous work showed that the size, elasticity and charge of multi-lamellar liposomes (MLLs) could not be considered separately to predict the fate of MLLs in the skin [1]. Based on this study, we developed several MLLs formulations containing a corticosteroid, betamethasone 17-valerate (B17) to transport the drug into the stratum corneum, living epidermis, dermis or through the skin. MLLs encapsulation efficiency was found to exceed 74 ± 3 % in all cases. In addition, we showed that MLLs protected the corticosteroid from thermal degradation. Comparing the penetration depth of all MLLs within artificial skin measured by Raman imaging, we established an equation for its determination, given the MLLs elasticity and size. This equation was verified experimentally on human explants: quantification of B17 in each skin layer, as well as its transdermal passage by ultra-high performance liquid chromatography, confirmed that B17 was predominantly and significantly transported in the desired layer. Eventually, we showed the benefits in using B17-loaded MLLs instead of a B17-containing pharmaceutical cream in terms of B17 penetration and thermal degradation. [ABSTRACT FROM AUTHOR]