Human Skin Research Articles

In situ study of the effect of endogenous and exogenous agents on color stability, hardness, and surface roughness of an elastomer for facial prostheses.

To evaluate in situ the influence of sweat, oil, sunscreen, and disinfectant solution on the color stability, hardness, and roughness of elastomer for facial prostheses. Standardized and intrinsically pigmented specimens remained in contact with human skin from the same person for 30days, considering exposures (n=36 per group), absent of exposition (Control, C); sweat and oiliness contact (SO); sweat and oiliness associated with sunscreen (SOS); 0.12% chlorhexidine digluconate immersion (CD0.12%); and all agents exposed (SOSCD). The main variables were color change (CIELab and National Standard Bureau system, NBS), Shore A hardness, and surface roughness, measured at baseline and 30days. Qualitative analyses were performed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The data were analyzed by Kruskal-Wallis tests (color) and two-way ANOVA (hardness and roughness) with Sidak post-test (α=0.05). CD0.12% (1.54±0.49) and SOSCD (2.10±1.03) had similar effects and caused the smallest color changes, considered mild and noticeable (NBS), respectively. SOS promoted the greatest color change (6.99±1.43, NBS: large) and hardness (17.97±0.56); SOS promoted intermediate roughness (3.48±1.05) between SOSCD (2.25±0.53), and two similar groups: C (4.46±0.95), and CD0.12% (4.39±1.26). The qualitative analysis showed an irregular, dense, dry, and whitish layer on the surface of the specimens exposed to sunscreen, which was reduced when in contact with 0.12% chlorhexidine digluconate. Endogenous and exogenous factors are capable of altering elastomer properties. The 0.12% chlorhexidine digluconate minimized the changes caused by sweat, oil, and sunscreen.

The HOCl dry fog-is it safe for human cells?

This study aims to investigate if high-concentration HOCl fogging disinfection causes cytotoxicity and genotoxicity to cultured primary human skin fibroblasts. The cells were exposed to a dry fog of HOCl produced from solutions with a concentration of 300 ppm (5.72 mM) or 500 ppm (9.53 mM). After four times when fibroblasts were exposed to aerosolized HOCl at a concentration of 500 ppm for 9 minutes, significant cytotoxicity and genotoxicity effects were observed. Significant changes in the morphology of fibroblasts and cell death due to membrane disruption were observed, independent of the number of exposures. Flow cytometry analyses performed under these experimental conditions indicated a decrease in the number of cells with an intact cell membrane in the exposed samples compared to the sham samples, dropping to 49.1% of the total cells. Additionally, under the same conditions, the neutral comet assay results demonstrated significant DNA damage in the exposed cells. However, no analogous damages were found when the cells were exposed to aerosolized HOCl generated from a 300-ppm solution for 3 minutes, whether once or four times. Therefore, we have concluded that aerosolized HOCl in dry fog, with a concentration exceeding 300 ppm, can cause cytotoxic and genotoxic effects on human skin fibroblasts.

Effective prediction of human skin cancer using stacking based ensemble deep learning algorithm

ABSTRACT Automated diagnosis of cancer from skin lesion data has been the focus of numerous research. Despite that it can be challenging to interpret these images because of features like colour illumination changes, variation in the sizes and forms of the lesions. To tackle these problems, the proposed model develops an ensemble of deep learning techniques for skin cancer diagnosis. Initially, skin imaging data are collected and preprocessed using resizing and anisotropic diffusion to enhance the quality of the image. Preprocessed images are fed into the Fuzzy-C-Means clustering technique to segment the region of diseases. Stacking-based ensemble deep learning approach is used for classification and the LSTM acts as a meta-classifier. Deep Neural Network (DNN) and Convolutional Neural Network (CNN) are used as input for LSTM. This segmented images are utilized to be input into the CNN, and the local binary pattern (LBP) technique is employed to extract DNN features from the segments of the image. The output from these two classifiers will be fed into the LSTM Meta classifier. This LSTM classifies the input data and predicts the skin cancer disease. The proposed approach had a greater accuracy of 97%. Hence, the developed model accurately predicts skin cancer disease.

Cellulose nanocomposite tough hydrogels: synergistic self‐healing, adhesive and strain‐sensitive properties

AbstractRecent advancements are notable in electrically conductive hydrogels emulating human skin functions. However, a significant challenge remains: crafting a single conductive gel that integrates self‐healing, robust mechanical strength, and excellent electrical traits. Our innovation lies in a strong, lightweight, curable gel achieved through multiple coordination bonds between cellulose crystals and acid‐treated multi‐walled carbon nanotubes (MWCNTs) in a polymer network. Embedded MWCNTs act as dynamic bridges within a porous structure, giving exceptional mechanical performance. Reversible coordination interactions confer remarkable recovery and reliable mechanical and electrical self‐healing. Additionally, these ionic gels function as adaptable stress sensors, detecting significant movements like finger and joint motions. This work introduces MWCNT‐incorporated nanomaterials with good stretchability, high ion conductivity, remarkable self‐healing nature, and good stress sensitivity. Such proteins hold promise for electronic sensors, wearable devices, and healthcare monitoring, unveiling a path to diverse applications. Our study addresses challenges and unlocks possibilities for materials that can adapt, withstand, and sense in innovative ways. © 2024 Society of Chemical Industry.

Transferosomes: Advancing Vesicular Drug Delivery Systems for Dermatological Disorders - A Comprehensive Review

Abstract: The human skin is the largest organ, is a vital interface with the external environment, and maintains homeostasis through its layered structure of epidermis, dermis, and hypodermis. The epidermis forms a strong barrier against microorganisms, and the dermis consists of essential components like collagen and melanin, and the hypodermis aids in insulation and energy storage. The skin diseases, spanning the epidermis, dermis, and subcutaneous tissue, include psoriasis, dermatitis, acne, hyperpigmentation, and aging. The nanocarrier-based drug delivery, particularly transferosomes, shows promise in treating dermatological conditions. Transfersomes are composed of phospholipids and edge activators, and navigate skin structures with flexibility, enhancing drug permeation. They offer continuous drug release, accommodating both lipophilic and hydrophilic drugs, and respond to osmotic gradients, optimizing transdermal delivery. Despite being non-invasive, formulation challenges and stability issues require attention. Studies demonstrate transferosomes' efficacy in treating conditions like acne, psoriasis, and melasma, demonstrating their potential for targeted drug delivery and overcoming conventional limitations in dermatology.

Dengue virus exploits autophagy vesicles and secretory pathways to promote transmission by human dendritic cells.

Dengue virus (DENV), transmitted by infected mosquitoes, is a major public health concern, with approximately half the world's population at risk for infection. Recent decades have increasing incidence of dengue-associated disease alongside growing frequency of outbreaks. Although promising progress has been made in anti-DENV immunizations, post-infection treatment remains limited to non-specific supportive treatments. Development of antiviral therapeutics is thus required to limit DENV dissemination in humans and to help control the severity of outbreaks. Dendritic cells (DCs) are amongst the first cells to encounter DENV upon injection into the human skin mucosa, and thereafter promote systemic viral dissemination to additional human target cells. Autophagy is a vesicle trafficking pathway involving the formation of cytosolic autophagosomes, and recent reports have highlighted the extensive manipulation of autophagy by flaviviruses, including DENV, for viral replication. However, the temporal profiling and function of autophagy activity in DENV infection and transmission by human primary DCs remains poorly understood. Herein, we demonstrate that mechanisms of autophagosome formation and extracellular vesicle (EV) release have a pro-viral role in DC-mediated DENV transmission. We show that DENV exploits early-stage canonical autophagy to establish infection in primary human DCs. DENV replication enhanced autophagosome formation in primary human DCs, and intrinsically-heightened autophagosome biogenesis correlated with relatively higher rates of DC susceptibility to DENV. Furthermore, our data suggest that viral replication intermediates co-localize with autophagosomes, while productive DENV infection introduces a block at the late degradative stages of autophagy in infected DCs but not in uninfected bystander cells. Notably, we identify for the first time that approximately one-fourth of DC-derived CD9/CD81/CD63+ EVs co-express canonical autophagy marker LC3, and demonstrate that DC-derived EV populations are an alternative, cell-free mechanism by which DCs promote DENV transmission to additional target sites. Taken together, our study highlights intersections between autophagy and secretory pathways during viral infection, and puts forward autophagosome accumulation and viral RNA-laden EVs as host determinants of DC-mediated DENV infection in humans. Host-directed therapeutics targeting autophagy and exocytosis pathways thus have potential to enhance DC-driven resistance to DENV acquisition and thereby limit viral dissemination by initial human target cells following mosquito-to-human transmission of DENV.

The interplay of Pseudomonas aeruginosa and Staphylococcus aureus in dual-species biofilms impacts development, antibiotic resistance and virulence of biofilms in in vitro wound infection models.

Due to high tolerance to antibiotics and pronounced virulence, bacterial biofilms are considered a key factor and major clinical challenge in persistent wound infections. They are typically composed of multiple species, whose interactions determine the biofilm's structural development, functional properties and thus the progression of wound infections. However, most attempts to study bacterial biofilms in vitro solely rely on mono-species populations, since cultivating multi-species biofilms, especially for prolonged periods of time, poses significant challenges. To address this, the present study examined the influence of bacterial composition on structural biofilm development, morphology and spatial organization, as well as antibiotic tolerance and virulence on human skin cells in the context of persistent wound infections. By creating a wound-mimetic microenvironment, the successful cultivation of dual-species biofilms of two of the most prevalent wound pathogens, Pseudomonas aeruginosa and Staphylococcus aureus, was realized over a period of 72 h. Combining quantitative analysis with electron microscopy and label-free imaging enabled a comprehensive evaluation of the dynamics of biofilm formation and matrix secretion, revealing a twofold increased maturation of dual-species biofilms. Antibiotic tolerance was comparable for both mono-species cultures, however, dual-species communities showed a 50% increase in tolerance, mediated by a significantly reduced penetration of the applied antibiotic into the biofilm matrix. Further synergistic effects were observed, where dual-species biofilms exacerbated wound healing beyond the effects observed from either Pseudomonas or Staphylococcus. Consequently, predicting biofilm development, antimicrobial tolerance and virulence for multi-species biofilms based solely on the results from mono-species biofilms is unreliable. This study underscores the substantial impact of a multi-species composition on biofilm functional properties and emphasizes the need to tailor future studies reflecting the bacterial composition of the respective in vivo situation, leading to a more comprehensive understanding of microbial communities in the context of basic microbiology and the development of effective treatments.

Artificial Tactile Receptor System for Sensitive Pressure-Neural Spike Conversion.

An artificial tactile receptor is crucial for e-skin in next-generation robots, mimicking the mechanical sensing, signal encoding, and preprocessing functionalities of human skin. In the neural network, pressure signals are encoded in spike patterns and efficiently transmitted, exhibiting low power consumption and robust tolerance for bit error rates. Here, we introduce a highly sensitive artificial tactile receptor system integrating a pressure sensor, axon-hillock circuit, and neurotransmitter release device to achieve pressure signal coding with patterned spikes and controlled neurotransmitter release. Owing to the heightened sensitivity of the axon-hillock circuit to pressure-mediated current signals, the artificial tactile receptor achieves a detection limit of 10 Pa that surpasses the human tactile receptors, with a wide response range from 10 to 5 × 105 Pa. Benefiting from the appreciable pressure-responsive performance, the potential application of an artificial tactile receptor in robotic tactile perception has been demonstrated, encompassing tasks such as finger touch and human pulse detection.

Designed Mannosylerythritol Lipid Analogues Exhibiting Both Selective Cytotoxicity Against Human Skin Cancer Cells and Recovery Effects on Damaged Skin Cells.

Mannosylerythritol lipids (MELs) are a class of amphipathic molecules bearing a hydrophilic 4-O-β-D-mannopyranosyl-D-erythritol skeleton. Here, we designed and synthesized four kinds of MEL analogues R-MEL-A ([2R,3S]-erythritol type), S-mannosylthreitol lipid (MTL)-A ([2S,3S]-threitol type), R-MTL-A ([2R,3R]-threitol type), and α-S-MEL-A ([2S,3R]-erythritol type) using our previously reported boron-mediated aglycon delivery (BMAD) method and a neighboring group assisted glycosylation method. The selective cytotoxicity of the target compounds against cancer cells was evaluated, with R-MTL-A showing the highest selective cytotoxicity against human skin squamous carcinoma HSC-5 cells. Our findings suggest that R-MTL-A induces necrosis-like cell death against HSC-5 cells by decreasing cell membrane fluidity. R-MTL-A also exhibits an efficient recovery effect on damaged skin cells, indicating that R-MTL-A has potential as a lead compound for new cosmeceuticals with both cancer cell-selective toxicity and recovery effects on damaged skin cells.

Luminescent lanthanide hydrogen-bonded organic frameworks for rapid detection of benzophenone-3

2-hydroxy-4-methoxybenzophenone (BP-3) is a common ingredient in sunscreens that can protect human hair and skin from ultraviolet rays. However, it is poisonous to a number of marine organisms, such as algae and corals. Herein, we constructed a new hydrogen-bonded organic framework (HOF) by assembling melamine with pyridine 2,6-dicarboxylic acid (MA-DPA). Subsequently, lanthanide HOF (Ln@MA-DPA) was obtained by anchoring lanthanide ions to the HOF via the coordination of surface carboxylic acid and nitrogen atom. Significantly, Tb@MA-DPA exhibits exceptional luminescent sensing behavior towards BP-3 in aqueous condition, with a limit of detection (LOD) as low as 0.72 μM, and possesses the advantages of high selectivity, fast response and recyclability. We believe that the reported sensor will undoubtedly expand the application scope of HOFs and offers a novel avenue for utilizing HOFs in marine pollution monitoring.

Development of 4-phenylbutyric acid microsponge gel formulations for the treatment of lewisite-mediated skin injury.

Lewisite, a chemical warfare agent, causes skin blisters, erythema, edema, and inflammation, requiring mitigation strategies in case of accidental or deliberate exposure. 4-phenyl butyric acid (4-PBA), a chemical chaperone, reduces endoplasmic reticulum stress and skin inflammation. The study aimed to encapsulate 4-PBA in microsponges for effective, sustained delivery against lewisite injury. Porous microsponges in a topical gel would potentially sustain delivery and improve residence time on the skin. Microsponges were developed using the quasi-emulsion solvent diffusion method with Eudragit RS100. Optimized formulation showed 10.58%w/w drug loading was incorporated in a carboxymethylcellulose (CMC) and Carbopol gel for in vitro release and permeation testing using dermatomed human skin. A sustained release was obtained from all vehicles in the release study, and IVPT results showed that compared to the control (41.52 ± 2.54µg/sq.cm), a sustained permeation profile with a reduced delivery was observed for microsponges in PBS (14.16 ± 1.23µg/sq.cm) along with Carbopol 980 gel (12.55 ± 1.41µg/sq.cm), and CMC gel (10.09 ± 1.23µg/sq.cm) at 24h. Optimized formulation showed significant protection against lewisite surrogate phenyl arsine oxide (PAO) challenged skin injury in Ptch1+/-/SKH-1 hairless mice at gross and molecular levels. A reduction in Draize score by 29%, a reduction in skin bifold thickness by 8%, a significant reduction in levels of IL-1β, IL6, and GM-CSF by 54%, 30%, and 55%, respectively, and a reduction in apoptosis by 31% was observed. Thus, the translational feasibility of 4-PBA microsponges for effective, sustained delivery against lewisite skin injury is demonstrated.

Controlling the formation of ionic complex vesicles through double-tailed surfactants.

Liposomes are often used in cosmetics since they are naturally derived and have excellent texture enhancing capabilities. However, when preparing them by using phospholipids with unsaturated acyl groups, they easily suffer from oxidative degradation. Accordingly, hydrogenated phospholipids are preferred, however, it is difficult to prepare stable liposomes due to its high gel-liquid crystalline phase transition temperature. On the other hand, although dialkyl dimethyl ammonium type cationic surfactants are widely known to form vesicles, they have rarely been used for skincare products except for water-in-oil type emulsion creams stabilized by organically modified clay minerals. We decided to overcome all of the problems above through ionic complex vesicles formed by double-tailed cationic and anionic surfactants. Distearyl dimethyl ammonium chloride (DSAC) and sodium dilauramidoglutamide lysine (DLGL) were selected as cationic and anionic surfactants, respectively. Differential scanning calorimetry (DSC) and small- and wide-angle X-ray scattering (SWAXS) measurements were performed to confirm the DSAC/DLGL/water ternary phase diagram. Newly developed ionic complex vesicle formation was confirmed by cryogenic transmission electron microscopy (cryo-TEM). The adsorbed cosmetic film structure on the skin invivo was evaluated through the polarized infrared external reflection (PIR-ER). Finally, a cosmetic lotion formula was developed and the vesicle size was determined by dynamic light scattering (DLS). DSC and SWAXS data indicated that stable vesicles could be obtained at a molar ratio of DLGL to DSAC = 6:4. At this molar ratio, multi lamellar vesicles with diameters less than 100 nm were observed through cryo-TEM. PIR-ER data revealed that the developed vesicles formed a highly perpendicular orientation to the human skin surface. We have succeeded in formulating a cosmetic lotion containing developed vesicles with a mean diameter of 63.2 nm, which was stable over 1 month at 0, 37, and 50°C. Our newly developed vesicles can be easily obtained through a coagulation process. Also, the adsorbed film structure supported by PIR-ER experiments implies that the developed lotion has an excellent texture that is the same as cosmetic lotions containing liposomes. Therefore, it's possible that this ionic complex vesicle could take the place of liposomes.

Antibacterial Silver Nanoparticle Containing Polydopamine Hydrogels That Enhance Re-Epithelization.

A polydopamine polyelectrolyte hydrogel was developed by ionic crosslinking dextran sulfate with a copolymer of polyethyleneimine and polydopamine. Gelation was promoted by the slow hydrolysis of glucono-δ-lactone. Within this hydrogel, silver nanoparticles were generated in situ, ranging from 25 nm to 200 nm in size. The antibacterial activity of the hydrogel was proportional to the quantity of silver nanoparticles produced, increasing as the nanoparticle count rose. The hydrogels demonstrated broad-spectrum antibacterial efficacy at concentrations up to 108 cells/mL for P. aeruginosa, K. pneumoniae, E. coli and S. aureus, the four most prevalent bacterial pathogens in chronic septic wounds. In ex vivo studies on human skin, biocompatibility was enhanced by the presence of polydopamine. Dextran sulfate is a known irritant, but formulations with polydopamine showed improved cell viability and reduced levels of the inflammatory biomarkers IL-8 and IL-1α. Silver nanoparticles can inhibit cell migration, but an ex vivo human skin study showed significant re-epithelialization in wounds treated with hydrogels containing silver nanoparticles.

Imperceptible augmentation of living systems with organic bioelectronic fibres

AbstractThe functional and sensory augmentation of living structures, such as human skin and plant epidermis, with electronics can be used to create platforms for health management and environmental monitoring. Ideally, such bioelectronic interfaces should not obstruct the inherent sensations and physiological changes of their hosts. The full life cycle of the interfaces should also be designed to minimize their environmental footprint. Here we report imperceptible augmentation of living systems through in situ tethering of organic bioelectronic fibres. Using an orbital spinning technique, substrate-free and open fibre networks—which are based on poly (3,4-ethylenedioxythiophene):polystyrene sulfonate—can be tethered to biological surfaces, including fingertips, chick embryos and plants. We use customizable fibre networks to create on-skin electrodes that can record electrocardiogram and electromyography signals, skin-gated organic electrochemical transistors and augmented touch and plant interfaces. We also show that the fibres can be used to couple prefabricated microelectronics and electronic textiles, and that the fibres can be repaired, upgraded and recycled.

Skin Disease Detection

The human skin is a remarkable organ susceptible to a myriad of know and unknown diseases. Many of these ailment are widespread, with some ranking among common worldwide. The complexity of diagnosing these diseases is compounded by challenges such as variations in skin texture, the presence of hair, and diverse skin colors. In some areas have limited access to medical facilities, individuals often neglect early symptoms, leading to exacerbated conditions over time. Furthermore, traditional diagnostic methods for skin diseases are time-consuming. To address these challenges, there is a critical need to develop advanced diagnostic methods utilizing machine learning techniques to enhance accuracy cross various skin diseases. Machine learning algorithms have proven valuable in medical applications, leveraging image feature values to facilitate decision-making. The diagnostic process involves three key stages: feature extraction, training, and testing. By employing machine learning technology, these algorithms learn from a diverse set of skin images o enhance their diagnostic capabilities. The primary goal is to significantly improved the accuracy of skin disease detection. This study focuses on utilizing color and texture features for the classification of skin diseases. The distinctive color of healthy skin differs from that affected by disease, while texture features effectively discern smoothness, coarseness, and regularity in images. Key features such as texture, color, and shape phyla pivotal role in image classification. The incorporation of convolution neural networks (CNN) further augments the capabilities of image classification in the realm of skin disease diagnosis

CD169+ Skin Macrophages Function as a Specialized Subpopulation in Promoting Psoriasis-like Skin Disease in Mice.

Skin macrophages are critical to maintain and restore skin homeostasis. They serve as major producers of cytokines and chemokines in the skin, participating in diverse biological processes such as wound healing and psoriasis. The heterogeneity and functional diversity of macrophage subpopulations endow them with multifaceted roles in psoriasis development. A distinct subpopulation of skin macrophages, characterized by high expression of CD169, has been reported to exist in both mouse and human skin. However, its role in psoriasis remains unknown. Here, we report that CD169+ macrophages exhibit increased abundance in imiquimod (IMQ) induced psoriasis-like skin lesions. Specific depletion of CD169+ macrophages in CD169-ditheria toxin receptor (CD169-DTR) mice inhibits IMQ-induced psoriasis, resulting in milder symptoms, diminished proinflammatory cytokine levels and reduced proportion of Th17 cells within the skin lesions. Furthermore, transcriptomic analysis uncovers enhanced activity in CD169+ macrophages when compared with CD169- macrophages, characterized by upregulated genes that are associated with cell activation and cell metabolism. Mechanistically, CD169+ macrophages isolated from IMQ-induced skin lesions produce more proinflammatory cytokines and exhibit enhanced ability to promote Th17 cell differentiation in vitro. Collectively, our findings highlight the crucial involvement of CD169+ macrophages in psoriasis development and offer novel insights into the heterogeneity of skin macrophages in the context of psoriasis.

P.144 Comparative analysis of spinal cord-derived and induced pluripotent-derived neural stem & progenitor cells for SCI therapy

Background: Induced pluripotent stem cells (iPSCs) have revolutionized spinal cord injury (SCI) treatment by generating neural stem/progenitor cells (NSPCs). However, understanding how iPSC-derived NSPCs compare to authentic spinal cord NSPCs remains unclear. This study thoroughly characterizes bona fide spinal cord NSPCs and their isogenic iPSC-derived counterparts, iPSC-SC and iPSC-Br. Methods: Human spinal cord and skin tissue were obtained with ethics approval to establish primary NSPC cultures. iPSCs were derived from these primary cells and differentiated into iPSC-SC and iPSC-Br NSPCs. Assessments encompassed differentiation, proliferation capabilities, immunostaining, and RNA sequencing for differential gene expression. Results: Functional and transcriptional differences were identified between bona fide NSPCs and iPSC-SC/iPSC-Br. Bona fide and iPSC-SC NSPCs exhibited spinal cord regionalization, while iPSC-Br displayed forebrain regionalization. iPSC-derived NSPCs shared features reminiscent of early developmental stages, including embryonic patterning genes and increased proliferation rates. Notably, differentiation profiles were most similar between bona fide and iPSC-Br, with substantial distinctions observed between bona fide and iPSC-SC. Conclusions: This study unveils unique regional, developmental, and functional characteristics distinguishing spinal cord NSPCs from iPSC-derived counterparts. Addressing these disparities holds promise for enhancing iPSC-derived NSPC therapies in spinal cord injuries, contributing to a deeper understanding of their potential applications in regenerative medicine.

Molecular mechanisms of human papilloma virus related skin cancers: A review.

The human papillomavirus (HPV) belongs to the Papillomaviridae family of viruses which includes small, double-stranded DNA viral agents. Approximately 90% of HPV infections occur asymptomatically and resolve spontaneously. However, infection with high-risk viral strains can lead to the development of preneoplastic lesions, with an increased propensity to become cancerous. The location of these malignancies includes the oral cavity, cervix, vagina, anus, and vulva, among others. The role of HPV in carcinogenesis has already been demonstrated for the aforementioned neoplasia. However, regarding skin malignancies, the mechanisms that pinpoint the role played by HPV in their initiation and progression still elude our sight. Until now, the only fully understood mechanism of viral cutaneous oncogenesis is that of human herpes virus 8 infection in Kaposi sarcoma. In the case of HPV infection, however, most data focus on the role that beta strains exhibit in the oncogenesis of cutaneous squamous cell carcinoma (cSCC), along with ultraviolet radiation (UVR) and other environmental or genetic factors. However, recent epidemiological investigations have highlighted that HPV could also trigger the onset of other non-melanocytic, for example, basal cell carcinoma (BCC), and/or melanocytic skin cancers, for example, melanoma. Herein, we provide an overview of the role played by HPV in benign and malignant skin lesions with a particular focus on the main epidemiological, pathophysiological, and molecular aspects delineating the involvement of HPV in skin cancers.

Collagen hydrogel protects intestinal epithelial cells from indomethacin-induced damage: results of an in vitro experiment

INTRODUCTION. Indomethacin is a derivative of indoleacetic acid and has anti-inflammatory, analgesic and antipyretic effects. However, the results of numerous studies show that indomethacin, like many other nonsteroidal anti-inflammatory drugs (NSAIDs), have an inhibitory effect on the viability and functional activity of enterocytes. In this regard, the search for new ways to reduce the severity of side effects from the use of NSAIDs remains relevant. One of these approaches may be to enrich patients’ diets with non-drug biologically active compounds, including proteins. However, the effect of dietary proteins and biologically active peptides on NSAID-induced damage to the wall of the small intestine and stomach has not been sufficiently studied. AIM. To evaluate the ability of a collagen-containing dietary supplement to protect human duodenal epithelial cells (HuTu-80 line) from indomethacin-induced damage. MATERIALS AND METHODS. The composite collagen-containing hydrogel was provided by «FIRST ALIVE COLLAGEN» LLC (Russia) and is a registered dietary supplement. The work used a commercial culture of human skin fibroblast cells and human duodenal epithelial cells (line HuTu-80). The viability of intestinal cells and fibroblasts was assessed using light and fluorescence microscopy and flow cytometry methods. RESULTS AND DISCUSSION. It has been established that indomethacin inhibits cell growth, causes apoptosis and death of enterocytes, and also leads to the accumulation of cells in the S-phase, which indicates a disruption in the regulation of the cell cycle. It was revealed that collagen hydrogel prevents cell death caused by indomethacin and reduces the number of apoptotic cells in the population. The protective effect of collagen hydrogel is characterized by normalization of the cell cycle of enterocytes and restoration of their growth and proliferative activity. CONCLUSION. Thus, collagen hydrogel, in vitro, is able to reduce the pathogenic effect of indomethacin on human intestinal epithelial cells. The protective effect of collagen hydrogel is characterized by maintaining viability, inhibiting apoptotic processes, and maintaining cell cycle stability. The results obtained indicate the prospects of using a dietary supplement based on a composite collagen hydrogel as a prophylactic agent to reduce the risk of NSAID-associated gastrointestinal diseases. However, to confirm the therapeutic effectiveness of the dietary supplement, further research is necessary, both using experimental animal modeling of NSAID-associated diseases of the human gastrointestinal tract, and clinical studies.

Model to identify comfortable cloth fabric for human body during thermal stress due to physical exercise

Abstract Physical exercise enhances heat generation in human skin and subcutaneous tissues causing thermal stress. This thermal stress causes discomfort in the human body and deteriorates the physical performance of the human subjects. Appropriate choice of cloth for outer covering of human body is necessary to prevent this to provide comfort during the thermal stress. A mathematical model is proposed in this study to analyze the thermal stresses in human skin and subcutaneous tissues covered with various different cloth fabrics. The model considers four compartments namely cloth, epidermis, dermis, subcutaneous tissues. The bioheat equation along with appropriate boundary condition is employed in this model for one dimensional unsteady state case. The numerical simulation is performed using forward and central finite difference formulas. The findings have been utilized to examine how different types of fabric impact thermal stress experienced by the layers of human skin during physical activity. The polyester is found to be superior in comparison to cotton fabric as it shows less thermal stress and thus can be concluded to be more comfortable as a dress material.