Skin Regions Research Articles

Effects of structural parameters on radial crashworthiness of 3D braided hybrid tubes with Janus structure

Hybrid fiber reinforced plastic (HFRP) composites have been widely used in various fields, but delamination is a fatal damage mode in laminated hybrid tubes. In the current paper, carbon fibers/Kevlar fibers hybrid tubes with Janus structure were fabricated by three-dimensional (3D) tubular braiding technique. The radial crushing performances of 3D braided Janus hybrid tubes were analyzed while hybrid layer ratio and yarn type were both considered. With the increase of hybrid layer ratio from 1:3 to 2:2 to 3:1, the specific energy absorption (SEA) increased 149% and 21.39% for specimens with carbon fibers placed on the skin region, and that decreased 12.46% and 10.66% for samples with Kevlar fibers arranged on the skin region. Furthermore, samples with Kevlar fibers arranged on the skin region presented excellent radial crashworthiness. The current work could be helpful for the design, fabrication and application of HFRP tubes.

Connective tissue cells of the skin: heterogeneity of fibroblasts and general properties of their subpopulations

Directing of experimental and clinical research requires integration of information on morphological and functional features of organs and tissue structures. One of the examples of such integration is the analysis of the histophysiology of the skin, in particular dermal fibroblasts – a mandatory cellular component of the dermis. They not only synthesize and organize the components of the extracellular matrix of the dermis, but also interact with each other and with other types of cells, playing a decisive role in the regulation of skin histophysiology. Other resident cells include epidermal, vascular, and nerve cells. In addition, the skin contains various cells of hematogenous origin. They contain a constitutive population of dendritic cells and a more dynamic population of leukocytes, which includes monocytes (macrophages), neutrophils, and lymphocytes. Dermal fibroblasts are a dynamic and diverse population of cells whose functions in skin in many respects remain unknown. Normal adult human skin contains at least three distinct subpopulations of fibroblasts, which occupy unique niches in the dermis. Fibroblasts from each of these niches exhibit distinctive differences when cultured separately. Specific differences in fibroblast histophysiology are evident in papillary dermal fibroblasts, which reside in the superficial dermis, and reticular fibroblasts, which reside in the deep dermis. Both of these subpopulations of fibroblasts differ from the fibroblasts that are associated with hair follicles. Fibroblasts engage in fibroblast-epidermal interactions during hair development and in interfollicular regions of skin. They also play an important role in cutaneous structural transformations.

Design optimization and testing of a morphing leading-edge with a variable-thickness compliant skin and a closed-chain mechanism

Climate warming and the increased demand in air travels motivate the aviation industry to urgently produce technological innovations. One of the most promising innovations is based on the smoothly continuous morphing leading-edge concept. This study proposes a two-step process for the design of a morphing leading-edge, including the optimization of the outer variable-thickness composite compliant skin and the optimization of the inner kinematic mechanism. For the compliant skin design, an optimization of the variable thickness composite skin is proposed based on a laminate continuity model, with laminate continuity constraint and other manufacturing constraints. The laminate continuity model utilizes a guiding sequence and a ply-drop sequence to describe the overall stacking sequence of plies in different thickness regions of the complaint skin. For the inner kinematic mechanism design, a coupled four-bar linkage system is proposed and optimized to produce specific trajectories at the actuation points on the stringer hats of the compliant skin, which ensures that the compliant skin can be deflected into the aerodynamically optimal profile. Finally, a morphing leading-edge is manufactured and tested. Experimental results are compared with numerical predictions, confirming the feasibility of the morphing leading-edge concept and the overall proposed design approach.

Uncommon dermatologic manifestation (paronychia) in a cat with diabetes mellitus

A 3.5-year-old male intact domestic short hair cat presented for a chronic wound and crusts over the claw and claw folds over several months. The cat was diagnosed with diabetes mellitus based on the presence of persistent hyperglycemia, glucosuria, and compatible clinical signs which consist of polyuria, polydipsia, polyphagia, and weight loss. Glipizide (Glucotrol XL, Pfizer, Indonesia) 2.5 mg orally twice daily was prescribed. By the seventeenth day, the patient's claws and skin around the paw had normalized and the abnormal claw sloughed off, revealing a normal claw underneath. Blood glucose, urinalysis and serum fructosamine were also normalized by the thirtieth day. The patient underwent diabetic remission, and the skin and claw lesions have remained in remission and not recurred since the treatment of the diabetes mellitus. This is the first report of a diabetic cat with dermatologic changes to the skin and claw regions. As the diabetes mellitus went into clinical remission, so too did the dermatologic manifestations, even without any specific dermatologic treatment.

Histomorphological development study for tadpoles and different regions of skin to the frogs (Bufotes variabilis) in Babylon city of Iraq

Histomorphological development study for tadpoles and different regions of skin to the frogs (Bufotes variabilis) in Babylon city of Iraq

CycleVTON: A Cycle Mapping Framework for Parser-Free Virtual Try-On

Image-based virtual try-on aims to transfer a target clothing onto a specific person. A significant challenge is arbitrarily matched clothing and person lack corresponding ground truth to supervised learning. A recent pioneering work leveraged an improved cycleGAN to enable one network to generate the desired image for another network during training. However, there is no difference in the result distribution before and after the clothing changes. Therefore, using two different networks is unnecessary and may even increase the difficulty of convergence. Furthermore, the introduced human parsing used to provide body structure information in the input also have a negative impact on the try-on result. How to employ a single network for supervised learning while eliminating human parsing? To tackle these issues, we present a Cycle mapping Virtual Try-On Network (CycleVTON), which can produce photo-realistic try-on results by using a cycle mapping framework without the parser. In particular, we introduce a flow constraint loss to achieve supervised learning of arbitrarily matched clothing and person as inputs to the deformer, thus naturally mimicking the interaction between clothing and the human body. Additionally, we design a skin generation strategy that can adapt to the shape of the target clothing by dynamically adjusting the skin region, i.e., by first removing and then filling skin areas. Extensive experiments conducted on challenging benchmarks demonstrate that our proposed method exhibits superior performance compared to state-of-the-art methods.

A dermatological odyssey: Levamisole\'s Triumph over warts, vitiligo, dermatophytosis, and pityriasis versicolor in a young patient

In our case, we observe the presence of various conditions within the same patient, including prevalent benign lesions caused by the human papillomavirus (HPV) known as warts. These warts, occurring in both mucosal and skin regions, can contribute to significant morbidity for affected individuals. Additionally, the patient exhibits vitiligo, a common acquired skin disorder characterized by well-demarcated white patches resulting from the loss of melanocytes in the epidermis. Although different theories exist regarding the pathogenesis of vitiligo, the exact etiology remains unknown. Alongside, the patient presents with two common fungal infections, namely pityriasis versicolor and dermatophytosis. The coexistence of all these dermatological conditions in a single patient highlights the complexity of the case.

Hybrid Interface Chemistry Enabling Mixed Conducting via Ultrafast Microwave Polarization Toward Dendrite-Free Zn Anodes.

Zn metal anodes in aqueous electrolytes suffer from interface issues including uncontrolled dendrite growth and undesired side reactions, resulting in their limited application in terms of short circuits and cell failure. Herein, a hybrid interface chemistry strategy is developed through ultrafast microwave polarization at the skin region of bare Zn. Owing to efficient Joule heating directed by abundant local hot spots at electron valleys, the rapid establishment of a dense interfacial layer can be realized within a minute. Stabilized Zn with suppressed side reactions or surface corrosion is therefore achieved due to the interfacial protection. Importantly, hybrid zincophilic sites involving laterally/vertically interconnected Cu-Zn intermetallic compound and Zn2+ -conductive oxide species ensure mixed charge conducting (denoted as CuHL@Zn), featuring uniformly distributed electric field and boosted Zn2+ diffusion kinetics. As a consequence, CuHL@Zn in symmetric cells affords lifespans of 2800 and 3200h with ultra-low polarization voltages (≈19 and 56mV) at a plating capacity of 1.0mAhcm-2 for 1 and 5mAcm-2 , respectively. The CuHL@Zn||MnO2 full cell further exhibits cycling stability with a capacity retention of over 80% for 500 cycles at 2Ag-1 .

Polaronic proton and diproton clustering in neutron-rich matter

We show that the strong spin-triplet neutron-proton interaction causes polaronic protons to occur in neutron matter at subnuclear densities and nonzero temperatures. As the neutron density increases, proton spectra exhibit a smooth crossover from a bare impurity to a repulsive polaron branch; this branch coexists with an attractive polaron branch. With the neutron density increased further, the attractive polarons become stable with respect to deuteron formation. For two adjacent protons, we find that the polaron effects and the neutron-mediated attraction are sufficient to induce a bound diproton, which leads possibly to diproton formation in the neutron skin region of neutron-rich nuclei in laboratories as well as in neutron stars.

Lipids in the American Alligator stratum corneum provide insights into the evolution of vertebrate skin

In terrestrial vertebrates, the outermost layer of the skin, the stratum corneum (SC), provides a durable and flexible interface with the environment and is comprised of corneocytes embedded in lipids. However, the morphology and lipid composition of the SC varies throughout evolutionary history. Because crocodilians and birds phylogenetically bracket the Archosaurian clade, lipid composition in crocodilian SC may be compared with that of birds and other vertebrates to make inferences about broader phylogenetic patterns within Archosaurs while highlighting adaptations in vertebrate skin. We identified and quantified lipid classes in the SC of the American Alligator (Alligator mississippiensis) from three skin regions varying in mobility. Our results find similarities in lipid composition between alligator and avian SC, including a high percentage of cerebrosides, a polar lipid previously found only in the SC of birds and bats. Furthermore, polar lipids were more abundant in the most mobile region of the SC. Because polar lipids bind with water to increase skin hydration and therefore its pliability under physical stress, we hypothesize that selection for lipids in Archosaurian SC was driven by the unique distribution of proteins in the SC of this clade, and cerebrosides may have served as pre-adaptations for flight.

Arterio-venous Anastomoses of the Sucquet-Hoyer Type: Complexity and Distribution in the Human Dermis.

Our study aims at providing detailed information on numbers, form, and spatial distribution of arterio-venous anastomoses of the Sucquet-Hoyer type in the dermis of the nail bed, nail fold corner, thumb pad, arm, nose, glabella, lip, and ear. It further aims at providing a system, which relies on objective morphologic criteria for classifying Sucquet-Hoyer canals (SHCs). Using high-resolution episcopic microscopy (HREM), digital volume data of eight samples of each skin region were produced. Virtual three-dimensional (3D) models of the dermally located SHCs were created, and their 3D tortuosity (τ) values were determined. Dermal SHCs were identified in all 24 finger samples and in 1 lip sample. Beneath a field of 2 × 2 mm2, an average of four were located in the nail bed, three in the dermis of the thumb pad, and one in the dermis of the nail fold corner. Only a single dermal SHC was found in one lip sample. No SHCs were observed in the dermis of the other samples. The τ values of the SHCs ranged from 1.11 to 10. Building on these values, a classification system was designed, which distinguishes four SHC classes. The dermal distribution of the SHCs of different classes was similar in all specimens.

Lymphatics-dependent modulation of the sensitization and elicitation phases of contact hypersensitivity

Allergic contact dermatitis is a common inflammatory skin disease comprising of two phases. During sensitization, immune cells are activated by exposure to various allergens, while repeated antigen exposure induces local inflammation during elicitation. Here, we utilized mouse models lacking lymphatics in different skin regions to characterize the role of lymphatics separately in the two phases, using contact hypersensitivity (CHS) as a model of the human disease. Lymphatic-deficient mice exhibited no major difference to single antigen exposure compared to controls. However, mice lacking lymphatics in both phases displayed reduced inflammation after repeated antigen exposure. Similarly, diminished immune response was observed in mice lacking lymphatics only in sensitization, while the absence of lymphatics only in the elicitation phase resulted in a more pronounced inflammatory immune response. This exaggerated inflammation is driven by neutrophils impacting regulatory T cell number. Collectively, our results demonstrate that skin lymphatics play an important but distinct role in the two phases of CHS. During sensitization lymphatics contribute to the development of the antigen-specific immunization, while in elicitation, they moderate the inflammatory response and leukocyte infiltration in a neutrophil-dependent manner. These findings underscore the need for novel therapeutic strategies targeting lymphatics in the context of allergic skin diseases.

Human Skin Detection and Segmentation Based on Convolutional Neural Networks

     Human skin detection is the process of classifying the image pixels or regions as skin or non-skin. Skin detection has many applications, such as face tracking, skin diseases, nudity recognition, hand gestures, video surveillance, web content filtering, and pornographic content filtering. Skin detection is a challenging problem due to skin color variation, the human race, aging, gender, makeup, complex backgrounds, etc. This paper suggests detecting the skin region in the image and finding the location of the skin based on a convolutional neural network. In this proposal, the proposed CNN will be modified by adding two layers before the first layer of CNN and after the last layer of CNN. The main purpose of these layers is to prepare the input image by using a sliding window, which inputs an indexed small part of the image into the CNN. The network classifies each part as skin or non-skin and then sends the result into the second suggested layer. After processing all the image pixels, the non-skin blocks are mapped to the original image as black regions. The final image contains the skin regions with black in the background. The contribution of the proposed method is the ability to detect the skin from any part of the human body, unlike previous works, which focused on one part of the body. The input image is processed as blocks instead of the entire image as in the previous works, and then in the output,  the original image is reconstructed. This method works well with most of the challenges that face the detection of skin, and finally, the designed network facilitates the localization and segmentation of the skin region almost accurately, while the previous networks focused on the classification of the image as skin or non-skin. The accuracy of the detection of skin when testing with images different from the training images was 95.4%.

Characteristics of the New Mast Cell-Rich Nodal Structure in the Rat Skin Surface.

: Acupuncture, practiced for millennia, lacks a clear anatomical definition for acupoints. A prevailing theory suggests that acupoints overlap with skin areas with higher mast cell density. Skin spots stained with intravenously infused Evans blue (EB), indicative of neurogenic inflammation, have recently been posited as acupoints in rats. : To demonstrate the concordance between EB-reactive skin spots and mast cell-enriched acupoints. : We employed staining and RNA-seq analysis to delineate the morphological characteristics and gene expression profiles of EB-reactive skin spots in rats. : EB infusion revealed a novel nodal structure on the rat skin surface, visible to the naked eye, with dimensions of approximately 1 mm in both diameter and height. Around 30 such nodes were identified on one side of the abdominal area, spaced roughly 3 mm apart, excluding the linea alba. RNA-seq analysis indicated that the gene expression patterns within these nodes markedly differed from both non-nodal skin areas and lymph nodes. Histological examination using toluidine blue revealed a significantly greater mast cell count in the nodes than in non-nodal skin regions. Additionally, the nodes stained positively with Alcian blue and Hemacolor, reagents known to mark primo vascular tissues. : Our findings suggest that EB-reactive nodes are indeed rich in mast cells. Further research is warranted to establish these skin nodes as surface primo nodes.

Near-infrared spectroscopy data for foot skin oxygen saturation in healthy subjects.

Our objective was to evaluate normative data for near-infrared spectroscopy (NIRS) in 110 healthy volunteers by Fitzpatrick skin type (FST) and region of the foot. We obtained measurements of the dorsum and plantar foot using a commercially available device (SnapshotNIR, Kent Imaging, Calgary Canada). On the dorsum of the foot, people with FST6 had significantly lower oxygen saturation compared to FST1-5 (p < 0.001), lower oxyhaemoglobin compared to FST2-5 (p = 0.001), but there was no difference in deoxyhaemoglobin. No differences were found on the plantar foot. When comparing dorsal and plantar foot, there was higher oxyhaemoglobin (0.40 ± 0.09 vs. 0.51 ± 0.12, p < 0.001) and deoxyhaemoglobin (0.16 ± 0.05 vs. 0.21 ± 0.05, p < 0.001) on the plantar foot, but no differences in oxygen saturation (dorsal 70.7 ± 10.8, plantar 70.0 ± 9.5, p = 0.414). In 6.4% of feet, there were black areas, for which no NIRS measurements could be generated. All areas with no data were on the dorsal foot and only found in FST 5-6. People with FST6 had significantly larger areas with no data compared to FST 5 (22.2 cm2  ± 20.4 vs. 1.9 cm2  ± 0.90, p = 0.007). These findings should be considered when using NIRS technology. Skin pigmentation should be evaluated in future NIRS studies.

Auto-Occlusive Lidocaine 7% and Tetracaine 7% Cream has Greater Pain Reduction Effects in Comparison with Lidocaine 4% Cream during Laser CO2 Dermabrasion Procedure in Preparation of Non-Cultured Autologous Epidermal Cell Grafting for Repigmentation in Vitiligo Subjects. An Intrasubject Pilot Evaluation Study

Introduction: Autologous non-cultured epidermal cell graft is a complex but promising technique in the treatment of vitiligo. Affected vitiligo areas should be de-epithelialized using an ablative Laser CO2 prior healthy epidermal cell inoculation. The dermabrasion (DA) procedure could be painful for the patient. To reduce the discomfort of this step topical anaesthesia is very often required. Topical anaesthetics available differ for composition, concentration of active anaesthetic molecules and methods of application (occlusion or not). An auto occlusive film-forming cream containing Lidocaine 7% and Tetracaine 7% (Pl-C) has shown in previous trials to be very effective in reducing discomfort during dermatological painful procedures like phototherapy, laser-conducted tattoo removal and laser resurfacing for skin ageing. Study Aim: To compare the clinical efficacy of Pl-C with Lidocaine 4% cream (As-C) in reducing the pain during Laser DA procedures in vitiligo subjects in preparation of autologous non-cultured epidermal transplantation. Subjects and Methods: We performed a prospective intra-subject randomized cases series in 7 subjects (4 men and 3 women) with segmental vitiligo with symmetrical lesions suitable for autologous non-cultured epidermal transplantation. Before the DA procedures the Pl-C or As-C were applied in a randomized fashion over the vitiligo areas to be treated. Pl-C was applied for 20 min without occlusion. The product was removed before the Laser procedure. As-C cream was applied for 30 min with occlusive band and then removed before the procedure. The treated skin regions had a mean area of 72±50 cm2; (range: 10 to 150 cm2). The primary outcome was the 100-mm Visual Analogue Scale (VAS) for patient-assessed pain evaluation with 0 mm value means no pain at all and 100 mm representing the worst possible pain. Results: Just after the Laser CO2 DA procedure the VAS score in PL-C area was 32±7 mm and 58±8 mm in As-C treated areas. This difference (-25±4 mm; 95% CI: from -16 to -35 mm) was highly statistically significant (p=0.0001) and clinically relevant (higher than the minimum clinically significant difference). Conclusion: The Lidocaine 7% and Tetracaine 7% auto occlusive cream is more effective than lidocaine 4% cream in reducing the pain associated with Laser CO2 DA procedures in preparation of skin autologous transplantation in vitiligo subjects.

Enhanced Skin Disease Detection and Classification System Using Deep Learning Technique

Even in this era of advanced technology, physicians still encounter challenges in accurately identifying skin diseases. Severe skin conditions necessitate urgent hospitalization, yet the diagnostic process involves costly tests with delayed results, exacerbating the worsening of infections. In rural areas, patients often ignore initial symptoms due to limited medical services, allowing conditions to progress unchecked. This underscores the pressing need for highly accurate automated skin disease detection systems. In response to this demand, we developed a multiclass convolutional neural network model aimed at discerning between healthy and diseased skin. Employing Python, we constructed a program utilizing this convolutional neural network with pre-trained networks- AlexNet and VGG19 to address the issue effectively. The primary objective of our project was to categorize five different skin illnesses using input images. By providing our model with pictures of affected skin regions, we aimed to detect ailments like Eczema, Nail fungus, Melanoma, Bullous, and Vascular Tumor. Upon processing the input image, our model would accurately identify and output the specific illness affecting the skin. This streamlined approach significantly aids in timely and accurate diagnosis, crucial for early intervention and treatment of various skin conditions

Rapid measurement of epidermal thickness in OCT images of skin

Epidermal thickness (ET) changes are associated with several skin diseases. To measure ET, segmentation of optical coherence tomography (OCT) images is essential; manual segmentation is very time-consuming and requires training and some understanding of how to interpret OCT images. Fast results are important in order to analyze ET over different regions of skin in rapid succession to complete a clinical examination and enable the physician to discuss results with the patient in real time. The well-known CNN-graph search (CNN-GS) methodology delivers highly accurate results, but at a high computational cost. Our objective was to build a computational core, based on CNN-GS, able to accurately segment OCT skin images in real time. We accomplished this by fine-tuning the hyperparameters, testing a range of speed-up algorithms including pruning and quantization, designing a novel pixel-skipping process, and implementing the final product with efficient use of core and threads on a multicore central processing unit (CPU). We name this product CNN-GS-skin. The method identifies two defined boundaries on OCT skin images in order to measure ET. We applied CNN-GS-skin to OCT skin images, taken from various body sites of 63 healthy individuals. Compared with CNN-GS, our described method reduced computation time by 130 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes$$\\end{document} with minimal reduction in ET determination accuracy (from 96.38 to 94.67%).

Human Foot Outperforms the Hand in Mechanical Pain Discrimination.

Tactile discrimination has been extensively studied, but mechanical pain discrimination remains poorly characterized. Here, we measured the capacity for mechanical pain discrimination using a two-alternative forced choice paradigm, with force-calibrated indentation stimuli (Semmes-Weinstein monofilaments) applied to the hand and foot dorsa of healthy human volunteers. In order to characterize the relationship between peripheral nociceptor activity and pain perception, we recorded single-unit activity from myelinated (A) and unmyelinated (C) mechanosensitive nociceptors in the skin using microneurography. At the perceptual level, we found that the foot was better at discriminating noxious forces than the hand, which stands in contrast to that for innocuous force discrimination, where the hand performed better than the foot. This observation of superior mechanical pain discrimination on the foot compared to the hand could not be explained by the responsiveness of individual nociceptors. We found no significant difference in the discrimination performance of either the myelinated or unmyelinated class of nociceptors between skin regions. This suggests the possibility that other factors such as skin biophysics, receptor density or central mechanisms may underlie these regional differences.

­­­A Comparative Evaluation of Antimicrobial Effect of Snuhi-Apamarg-Ksharsutra and Udumbara-Ksheer Sutra in the Management of Bhagandara (Fistula-In-Ano)

Bhagandara one of the eight grave disorders, pertaining the perianal region is arduous to treat, has been described in detail by Acharaya Sushruta. The Ayurvedic description of Bhagandara can be identified as associated with an anal fistula. An anal fistula is defined as an internal opening in the altered skin or mucosa of the anal canal or rectum and an exterior opening in the perianal skin region. Among the various modalities available for the treatment of bhagandara, ksharasutra is described as gold standards for treatment and cure. The ksharasutra possess antimicrobial properties and can be established as first line of treatment for bhagandar(fistula-in-ano). The modern approach for fistula-in-ano is surgical procedure. Antibiotics are commonly used along with surgery for the treatment of fistula-in-ano.  The aim of this study was to comparatively evaluate the antimicrobial properties amongst Snuhi-apamarga kshar sutra and Udumbara ksheer sutra. A total no. of 60 participants were enrolled as per the criteria for the study and pus samples were collected as per the standard operating procedure. Samples of Snuhi-apamarga kshar sutra and Udumbar ksheer sutra were already given in laboratory for testing the sensitivity. Reports were collected and analyzed on different parameters and conclusion was drawn accordingly. It was concluded that gram positive monomicrobial infections were more common especially involving staphylococci. Also, in the culture and sensitivity test Snuhi- apamarga ksharsutra was found to be more effective in comparison to Udumbara ksheer sutra as the microbes were highly sensitive to the Snuhi Apamarga kshar sutra. This can be contributed to the multiple contents in Snuhi Apamarga kshar sutra.