Atopic dermatitis (AD) is a chronic, allergic inflammatory skin disorder that lacks a definite cure. Using a mouse DNCB-induced AD-like skin lesions model, this study evaluated the potential therapeutic utility of tHGA as an oral and topical treatment for AD. Male BALB/c mice were sensitised and challenged with 1% and 0.5% DNCB on their shaved dorsal skin. Mice in the treatment group were administered tHGA (20, 40, and 80 mg/kg) orally three times per week for 2 weeks, or tHGA (0.2%, 1%, and 5%) topically once daily for 12 days. On day 34, the mice were euthanized, and blood and dorsal skin samples were obtained for analysis. All doses of orally and topically administered tHGA significantly improved scratching, epidermal thickness, blood eosinophilia and mast cell infiltration. There was a minor discrepancy between the two routes of administration, with orally treated tHGA showing significant reductions in Scoring of Atopic Dermatitis (SCORAD), tissue eosinophil infiltration, serum IgE and skin IL-4 levels with treatment of 40 and 80 mg/kg tHGA, whereas topically applied tHGA showed significant reductions in all dosages. These findings suggest that tHGA exhibited therapeutic potential for AD as both oral and topical treatment ameliorates AD-like symptoms in the murine model.

In persons with limb loss, prosthetic devices cause skin breakdown, largely because residual limb skin (nonvolar) is not intended to bear weight such as palmoplantar (volar) skin. Before evaluation of treatment efficacy to improve skin resiliency, efforts are needed to establish normative data and assess outcome metric reliability. The purpose of this study was to use optical coherence tomography to (i) characterize volar and nonvolar skin epidermal thickness and (ii) examine the reliability of optical coherence tomography. Four orientations of optical coherence tomography images were collected on 33 volunteers (6 with limb loss) at 2 time points, and the epidermis was traced to quantify thickness by 3 evaluators. Epidermal thickness was greater (P < .01) for volar skin (palm) (265.1 ± 50.9 μm, n = 33) than for both nonvolar locations: posterior thigh (89.8 ± 18.1 μm, n = 27) or residual limb (93.4 ± 27.4 μm, n = 6). The inter-rater intraclass correlation coefficient was high for volar skin (0.887-0.956) but low for nonvolar skin (thigh: 0.292-0.391, residual limb: 0.211-0.580). Correlation improved when comparing only 2 evaluators who used the same display technique (palm: 0.827-0.940, thigh: 0.633-0.877, residual limb: 0.213-0.952). Despite poor inter-rater agreement for nonvolar skin, perhaps due to challenges in identifying the dermal-epidermal junction, this study helps to support the utility of optical coherence tomography to distinguish volar from nonvolar skin.

In this study, an internal fingerprint-guided epidermal thickness of fingertip skin is proposed for optical image encryption based on optical coherence tomography (OCT) combined with U-Net architecture of a convolutional neural network (CNN). The epidermal thickness of fingertip skin is calculated by the distance between the upper and lower boundaries of the epidermal layer in cross-sectional optical coherence tomography (OCT) images, which is segmented using CNN, and the internal fingerprint at the epidermis-dermis junction (DEJ) is extracted based on the maximum intensity projection (MIP) algorithm. The experimental results indicate that the internal fingerprint-guided epidermal thickness is insensitive to pressure due to normal correlation coefficients and the encryption process between epidermal thickness maps of fingertip skin under different pressures. In addition, the result of the numerical simulation demonstrates the feasibility and security of the encryption scheme by structural similarity index matrix (SSIM) analysis between the original image and the recovered image with the correct and error keys decryption, respectively. The robustness is analyzed based on the SSIM value in three aspects: different pressures, noise attacks, and data loss. Key randomness is valid by the gray histograms, and the average correlation coefficients of adjacent pixelated values in three directions and the average entropy were calculated. This study suggests that the epidermal thickness of fingertip skin could be seen as important biometric information for information encryption.

BACKGROUND: Changes in the skin structure, including the collagen and elastin content, have been reported with massive weight loss (MWL) following bariatric metabolic surgery (BMS) and have been correlated to a higher risk of complications after body-contouring surgery (BCS). This study aimed at comparing the histological characteristics of the skin of patients having surgical MWL (SMWL) post-BMS to those with non-surgical massive weight loss (NSMWL).
METHODS: This prospective study compared the epidermal thickness, and collagen and elastin fibers content in 80 skin biopsies obtained from BCS procedures performed to patients who experienced MWL defined more than 50% of excess weight loss (%EWL) either SMWL (40 biopsies) or NSMWL (40 biopsies). Twenty biopsies in each group were obtained from abdominoplasties and 20 from breast reductions. Epidermal thickness was measured in H&E-stained sections, collagen fibers were assessed using Masson trichrome-stained sections, and elastin fibers were assessed using Modified Verhoeff\'s stained sections. Image analysis software was used to calculate the fractions of collagen and elastin fibers.
RESULTS: This study included 77 patients, 38 SMWL patients, and 39 NSMWL patients. The SMWL group had a significantly higher age (p < 0.001), a longer time interval from intervention (p < 0.001), higher initial weight (p < 0.001), higher initial BMI (p < 0.001), lower current weight (p = 0.005), lower current BMI (p < 0.001), and significantly higher %EWL than NSMWL group (p < 0.001). No significant differences were detected between the two groups regarding complications after abdominoplasty (p = 1.000). The elastic fibers content in the dermis was significantly higher in the abdominal region of the NSMWL group than SMWL (p = 0.029). All other parameters showed non-significant differences between NSMWL and SMWL in the skin of abdomen and breast.
CONCLUSIONS: The SMWL group had a significant reduction in elastic fiber content in the skin of the abdomen compared to the NSMWL group. The collagen content was equally reduced in both groups with non-significant differences in both breast and abdomen regions in both groups.

The epithelial-mesenchymal transition (EMT) is a phenomenon, in which epithelial cells acquire a mesenchymal cell phenotype. It is important during wound healing; however, chronic inflammation leads to excessive EMT and causes tissue barrier dysfunction with hyperplasia. EMT is induced by several cytokines, such as interleukin (IL)-4 and IL-13. Additionally, IL-4 and IL-13 are known to increase in atopic dermatitis (AD) characterized by intense itching and eczema. Therefore, we assumed that there was commonality between the respective EMT and AD phenotypes. Herein, we evaluated EMT marker expression in AD skin and demonstrated that EMT-maker Snai1 and Twist expression were increased in AD mice model and patients with AD. Moreover, the epithelial-marker keratin 5 and mesenchymal marker Vimentin were co-expressed in the skin epidermis of mice with AD, suggesting the existence of hybrid epithelial-mesenchymal (E/M) cells possessing both epithelial and mesenchymal characteristics. In fact, we found that ΔNp63a, a stabilizing factor for hybrid E/M cells, was upregulated in the skin epidermis of the AD model mouse. Interestingly, increased expression of EMT markers was observed even at a nonlesion site in a patient with AD without initial inflammation or scratching. Therefore, EMT-like phenomena may occur independently of wound healing in skin of patients with AD.

BACKGROUND: Noninvasive skin examination evolved rapidly in recent years, with multiphoton microscopy (MPM) and reflectance confocal microscopy (RCM) being used to image in-vivo skin at high resolution. The aim of this study is to compare the imaging clarity between the two techniques and measure the thickness of the epidermis in different body sites. We also measured the degree of skin aging with noninvasive tools.
METHODS: Fifty-six volunteers were evaluated and measured at three different body sites, including the cheek, volar forearm, and back. We used RCM and MPM to evaluate the clarity of each skin layer, including stratum corneum, stratum granulosum, stratum spinosum, dermo-epidermal junction, and dermis. We measured epidermal thickness (ET) at the three body sites in individuals of different ages and genders. We assessed skin aging by the second harmonic to autofluorescence aging index of dermis (SAAID), and multiple linear regression was used to analyze the factors affecting SAAID.
RESULTS: MPM had advantages in observation of stratum granulosum, collagen fiber, and elastic fiber (p < 0.001), but RCM provided better observation in dermo-epidermal junction layer (p < 0.001). The epidermis was thicker in the cheek area than the volar forearm and back in both RCM and MPM detection, and the average ET measured by MPM was lower than RCM. ET varied among the three body sites with significant differences (p < 0.05). ET was significantly lower at almost all sites in individuals above 40y (p < 0.05). SAAID decreased with age, and more rapidly in women. Cheeks have lower SAAID scores than other body sites.
CONCLUSIONS: MPM and RCM provide noninvasive methods for imaging skin and each method has its own advantages. Epidermal thickness and SAAID correlated with age, gender, and different body sites. MPM could also assess the degree of skin aging, which could guide the clinical treatment of patients with diffferent ages and genders in the above body sites.

Background: Burn injury is a global health problem that is most often caused by heat. A burn injury can cause high morbidity and mortality and requires high cost. Therefore, the use of plants as an herbal medicine has the potential to be developed in Indonesia. Aloe vera contains various active ingredients that help the wound healing process, such as glucomannan and acemannan which have the effects on the proliferation of macrophages, fibroblasts, and re-epithelialization. This study aimed to determine the effect of Aloe vera extract in repairing post-burn skin in rats that were analyzed from the number of macrophages, fibroblasts, and epidermal thickness. Methods: This is an experimental study with a posttest-only control group design using 54 Rattus norvegicus Wistar strain rats. The sampling method was simple random sampling consisting of 3 groups, i.e., I. standard group, which were normal rats; II. negative control group, which were given second-degree burns and treated with gel base (without Aloe vera extract); III. treatment groups, which were given second-degree burns and treated with Aloe vera extract gel. Each group was subdivided into three smaller groups (n = 6) according to the time the lesions were evaluated. Skin tissue samplings were carried out on days 3, 14, and 21 after injury to observe the number of macrophages, fibroblasts, and epidermal thickness. Results: There were significant differences in the mean number of macrophages, number of fibroblasts, and epidermal thickness in all groups ( p<0.05). Conclusion: Aloe vera extract could accelerate the healing process of burns in rats.

Dupilumab attenuates itch and skin inflammation in patients with atopic dermatitis (AD). However, itch-related events that are improved by dupilumab remain unclear. Therefore, the present study investigated changes in clinical scores, serum biomarkers, and the number of intraepidermal nerve fibers (IENFs) using skin biopsies and blood samples from 12 patients with moderate to severe AD before and after treatment with dupilumab. Clinical manifestations were assessed using eczema area and severity index (EASI) and visual analogue scale (VAS) scores at baseline and after 8 and 16 weeks of treatment. Serum levels of total immunoglobulin E (IgE), thymus and activation-regulated chemokine (TARC), interleukin (IL)-4, IL-13, IL-22, and IL-31 were examined by electrochemiluminescence, chemiluminescent enzyme immunoassays, ProQuantum immunoassays, and enzyme-linked immunosorbent assays (ELISA) at baseline and after 8 and 16 weeks of treatment. In skin biopsies from AD patients at baseline and after 16 weeks of treatment, IENFs were examined immunohistochemically with the anti-protein gene product (PGP) 9.5 antibody. The dupilumab treatment significantly improved EASI and VAS scores and decreased serum levels of TARC, IgE, and IL-22, whereas those of IL-13 and IL-31, and the number of IENFs remained unchanged and those of IL-4 increased. VAS scores were positively correlated with serum TARC, IL-22, and IgE levels and the degree of epidermal thickening. Serum IL-31 levels were positively correlated with the number of IENFs. These results suggest that serum TARC, IL-22, and IgE levels and epidermal thickness are itch-related events associated with dupilumab treatment and that serum IL-31 levels may reflect the degree of IENF density in AD patients. Therefore, dynamic changes may be used to assess the efficacy of dupilumab treatment to treat itching and inflammation in patients with AD.

Traditional high-frequency ultrasound (HFUS; 20 MHz) is a non-invasive method used to study skin in vivo but is not able to measure skin thickness accurately and to identify the dermal-epidermal junction (DEJ). Ultra-high frequency ultrasound (UHFUS; 70-100 MHz) has sub-millimetre resolution comparable to histology. The aim of this study was to identify, by UHFUS, the DEJ and to describe skin differences in healthy individuals by providing a measure of skin thickness, based on age and gender. We also described the bullous pemphigoid lesion. We enrolled 42 patients divided into 2 groups: A and B. Group A included 32 healthy volunteers aged 22-74 years. Group B consisted of 10 patients with bullous pemphigoid. For each patient in group A, 8 ultrasound (US) clips by 70 MHz probe were performed at forehead, cheek, nose, forearm, abdomen, chest, back and leg. For each patient in group B, 5 US images were acquired at blisters roofs and edges. In each US image, we measured thickness of stratum corneum (α-β), epidermis (α-γ) and epidermis plus dermis (α-δ). In both groups, we found the presence of 4 lines delimiting: the stratum corneum (the layer between α-line and β-line), the epidermis (distance between α- and γ-line), and the boundary between dermis and subcutis (δ-line). The γ-line corresponds to the point of detachment of the bullae. The abdominal α-β layer was thicker in males (p = 0.019) and α-δ thickness at cheeks (p < 0.001), chest (p = 0.007), back (p = 0.025) and forearm (p < 0.001). In females, α-γ thickness of the back was greater (p = 0.005). In old people compared to young, we noticed an increase of α-β layer at forehead and chest (p = 0.014), an increase of α-γ layer at forearm (p = 0.001), back (p = 0.024) and leg (p = 0.010) and an increase of α-δ layer at forehead (p = 0.001) and nose (p = 0.049). UHFUS is an advanced imaging technique that can detect both the DEJ and the boundary between dermis and subcutaneous tissue so that epidermal and dermal thickness can be measured with good accuracy. Regarding gender and age, skin differences obtained with UHFUS were comparable to other non-invasive methods.

This descriptive study examined the variation in ventral Crocodylus porosus (saltwater crocodile) belly skin. The study is the first to determine both intra and inter variation of C. porosus skin, epidermis and dermis thickness across the ventral belly region. Standardised ventral scales from across the belly region of a Hatchling (< 12months), Yearling (1-2 years) and Grow Out (>2 years) animals were examined using histological measurements for the stratum (s.) corneum, a combined measure for the remainder of the epidermis; the s. granulosum, s. spinosum and s. basale, and the dermis. This study determined that there was a thinning across all layers of the belly skin, from the head to the cloaca, and a decrease in thickness scales in lateral scales compared to midline scales. Variation within a scale was found predominately in the s. corneum and can be related to the change in keratin type from beta- to alpha- in the hinge (inter-scalar) region and the integumentary sensory organs. Future studies should utilise a larger sample size and consider less invasive imaging techniques.