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The development of cosmetic formulations with moisturizing and film-forming properties has been very important to help keep skin physiology and protection. In this context, this study aimed to develop a cosmetic formulation containing Tara gum and Brazilian berry extract and evaluate its physical-mechanical, film-forming, and sensory properties. A gel formulation was developed based on Tara gum added to Plinia cauliflora extract and was characterized by its spreadability profile and sensory properties. A clinical study was carried out with ten participants to evaluate the skin microrelief, stratum corneum water content, transepidermal water loss (TEWL), and skin morphological characteristics by reflectance confocal microscopy (RCM) before and after 2 h of application of the formulations. The formulation with Brazilian berry significantly decreased the work of shear parameter, which can be correlated with improved spreadability in the sensory analysis. The clinical study showed that both formulations improved skin hydration and reduced the TEWL. The RCM imaging analysis showed the visible film on the skin surface, a decrease in the size of furrows, an increase in the reflectance of the interkeratinocytes, and reflectance of the stratum corneum for both formulations. These results were more pronounced for the formulation containing Brazilian berry. The Tara gum in the gel formulation promoted the formation and visualization of a polymeric net on the stratum corneum surface, demonstrated by the images obtained from RCM. However, the formulation added with the Brazilian berry extract improved the skin microrelief, honeycomb pattern of the epidermis, and skin hydration in deeper layers of the epidermis.

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BACKGROUND: In insects, continuous growth requires the periodic replacement of the exoskeleton. Once the remains of the exoskeleton from the previous stage have been shed during ecdysis, the new one is rapidly sclerotized (hardened) and melanized (pigmented), a process collectively known as tanning. The rapid tanning that occurs after ecdysis is critical for insect survival, as it reduces desiccation, and gives the exoskeleton the rigidity needed to support the internal organs and to provide a solid anchor for the muscles. This rapid postecdysial tanning is triggered by the "tanning hormone", bursicon. Since bursicon is released into the hemolymph, it has naturally been assumed that it would act on the epidermal cells to cause the tanning of the overlying exoskeleton. RESULTS: Here we investigated the site of bursicon action in Drosophila by examining the consequences on tanning of disabling the bursicon receptor (encoded by the rickets gene) in different tissues. To our surprise, we found that rapid tanning does not require rickets function in the epidermis but requires it instead in peptidergic neurons of the ventral nervous system (VNS). Although we were unable to identify the signal that is transmitted from the VNS to the epidermis, we show that neurons that express the Drosophila insulin-like peptide ILP7, but not the ILP7 peptide itself, are involved. In addition, we found that some of the bursicon targets involved in melanization are different from those that cause sclerotization. CONCLUSIONS: Our findings show that bursicon does not act directly on the epidermis to cause the tanning of the overlying exoskeleton but instead requires an intermediary messenger produced by peptidergic neurons within the central nervous system. Thus, this work has uncovered an unexpected layer of control in a process that is critical for insect survival, which will significantly alter the direction of future research aimed at understanding how rapid postecdysial tanning occurs.

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The skin of the South American fur seal (Arctocephalus australis) is important for animal thermoregulation in both terrestrial and aquatic environments. Skin tissue samples were collected from A. australis for microscopic analysis and were related to anatomical references. The aim of this study was to describe the skin morphology, as well as to suggest the major anatomical regions and skin components involved in the thermoregulation of this species. Using light microscopy, the skin of six animals was examined based on histological, morphometric, and immunohistochemical criteria. Hair follicle morphology was examined using scanning electron microscopy. The skin was classified as either thick or thin based on its epidermal thickness. The thin epidermis regions had more abundant hair follicles, as well as high pigmentation, whereas the thick epidermis regions had very pigmented epidermal layers. Pigmentation of hair and skin is fundamental for protection against ultraviolet rays; moreover, hair is important in preventing abrasion, and provides an insulating layer against the external environment, which can be much colder than body temperature. Furthermore, the dermis is well vascularized, especially the superficial dermis. All regions of the skin have adaptations for maintaining the animal's condition in both terrestrial and aquatic environments. Among the studied regions, the interdigital region from hindflipper showed important morphological characteristics related to thermoregulation, such as having an epidermis of intermediate thickness, a dermis with a small number of hairs, a large amount of blood vessels, and sweat glands with large lumens, indicating that heat exchange in this region may be faster.

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BACKGROUND: Chronological skin aging causes the modification of genetic material through enzymes and proteins changes. The process reduces cellular proliferation, along with loss of tissue elasticity, reduced ability to regulate aqueous exchanges, and inefficient tissue replication. Appearance is negatively affected by cumulative changes in coloration, texture, and elasticity over time. The increase in the population's average life expectancy boosts the search for cosmetic therapies that can delay aging, mostly for the noninvasive modalities. Among the various options, radiofrequency therapy is a technique that can help reduce the effects of skin aging. AIM: Therefore, this study aims to review clinical evidence provided by scientific literature on the benefits of using radiofrequency therapy in reducing skin aging effects. METHODS: A review of the literature concerning skin aging, characteristics of radiofrequency therapy, and radiofrequency therapy in the treatment of skin laxity and mechanism of action was conducted using PubMed. RESULTS: The included studies have suggested that the mechanism of radiofrequency action is heating the dermis while preserving the epidermis. This heating causes immediate collagen denaturation, which is followed by the formation of new collagen, naturally providing skin tightening and greater elasticity. CONCLUSION: Even when used as single therapeutic modality, radiofrequency seems to meet the expectations in reducing the effects of skin aging.

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OBJECTIVE: To evaluate the difference in transepidermal water loss in patients diagnosed with hyperhidrosis and healthy subjects, in an air-conditioned environment. METHODS: Twenty patients diagnosed with hyperhidrosis and 20 healthy subjects were subjected to quantitative assessment using a closed-chamber device, in six previously established sites. RESULTS: The measurements showed different transepidermal water loss values for healthy subjects and patients with hyperhidrosis, especially in the hands and feet. In the Control Group, the median for the hands was 46.4g/m2/hour (p25: 36.0; p75: 57.6), while in the Hyperhidrosis Group, the median was 123.5g/m2/hour (p25: 54.3; p75: 161.2) - p<0.001. For the feet, the Control Group had a median of 41.5g/m2/hour (p25: 31.3; p75: 63.5) and the Hyperhidrosis Group, 61.2g/m2/hour (p25: 32.3; p75: 117) - p<0.02. Measurements of the axillas also showed differences. In the Control Group, the median was 14.8g/m2/hour (p25: 11.8; p75: 19.0) and, in the Hyperhidrosis Group, 83.5g/m2/hour (p25: 29.5; p75: 161.7) - p<0.001. CONCLUSION: Measuring transepidermal water loss is sufficient for diagnosis and follow-up of patients with hyperhidrosis.

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ABSTRACT Objective To evaluate the difference in transepidermal water loss in patients diagnosed with hyperhidrosis and healthy subjects, in an air-conditioned environment. Methods Twenty patients diagnosed with hyperhidrosis and 20 healthy subjects were subjected to quantitative assessment using a closed-chamber device, in six previously established sites. Results The measurements showed different transepidermal water loss values for healthy subjects and patients with hyperhidrosis, especially in the hands and feet. In the Control Group, the median for the hands was 46.4g/m2/hour (p25: 36.0; p75: 57.6), while in the Hyperhidrosis Group, the median was 123.5g/m2/hour (p25: 54.3; p75: 161.2) - p<0.001. For the feet, the Control Group had a median of 41.5g/m2/hour (p25: 31.3; p75: 63.5) and the Hyperhidrosis Group, 61.2g/m2/hour (p25: 32.3; p75: 117) - p<0.02. Measurements of the axillas also showed differences. In the Control Group, the median was 14.8g/m2/hour (p25: 11.8; p75: 19.0) and, in the Hyperhidrosis Group, 83.5g/m2/hour (p25: 29.5; p75: 161.7) - p<0.001. Conclusion Measuring transepidermal water loss is sufficient for diagnosis and follow-up of patients with hyperhidrosis.

RESUMO Objetivo Avaliar a diferença entre a perda transepidérmica de água aferida entre pacientes com e sem diagnóstico de hiperidrose, em ambiente climatizado. Métodos Foram selecionados 20 pacientes com diagnóstico de hiperidrose e 20 hígidos, submetidos à aferição de maneira quantitativa, com mensurador de câmara fechada, em seis locais previamente estabelecidos. Resultados As medidas realizadas mostraram valores diferentes de perda transepidérmica de água em pessoas hígidas e naquelas com hiperidrose, principalmente em mãos e pés. No Grupo Controle, a mediana das aferições em mãos foi 46,4g/m2/hora (p25: 36,0; p75: 57,6), enquanto, no Grupo Hiperidrose, obtivemos a mediana de 123,5g/m2/hora (p25: 54,3; p75: 161,2) - p<0,001. Já nos pés, a mediana no Grupo Controle foi 41,5g/m2/hora (p25: 31,3; p75: 63,5) e, no Grupo Hiperidrose, foi 61,2g/m2/hora (p25: 32,3; p75: 117) - p<0,02. As medidas das regiões axilares também mostraram diferença. No Grupo Controle, obtivemos mediana 14,8g/m2/hora (p25: 11,8; p75: 19,0) e, no Hiperidrose, 83,5g/m2/hora (p25: 29,5; p75: 161,7) - p<0,001. Conclusão A mensuração da perda transepidérmica de água é suficiente para diagnóstico e acompanhamento de pacientes com hiperidrose.

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BACKGROUND: Knowledge of skin biology and its alterations in different populations is very important for the development of appropriate skincare strategies. OBJECTIVES: To evaluate and compare morphological, structural and biophysical properties of photoaged skin in French and Brazilian populations, using biophysical and skin-imaging techniques. METHODS: Forty-one French and 41 Brazilian healthy, female volunteers aged between 40 and 65 years were enrolled. Each participant completed a questionnaire concerning habits related to cosmetic use, sun exposure and sun protection during different life periods. Skin on the face and volar forearm was evaluated using noninvasive techniques, to determine skin colour, transepidermal water loss (TEWL), stratum corneum water content, skin microrelief, skin viscoelasticity and dermis structure. Reflectance confocal microscopy was used to measure epidermal layer thickness and epidermal morphological and structural characteristics. RESULTS: Compared with Brazilian skin, French skin was more hydrated, had a lower TEWL and presented a distinct viscoelastic profile on the forearms and face. Brazilian facial skin was more wrinkled, and the dermis was less echogenic on the forearms and face. The French participants had thicker stratum corneum. Brazilian facial skin presented a higher prevalence of rete ridge effacement, low interkeratinocyte reflectance, huddled collagen and solar elastosis. CONCLUSIONS: Morphological, structural and biophysical differences were found when assessing the skin of the Brazilian and French participants, who were exposed to different environmental factors.

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The development of new wound therapies, such as bioengineered skin equivalents, is an ongoing process. Multi-potent mesenchymal stem cells (MSCs) give rise to many tissue lineages and have been implicated in wound healing making them a potential candidate for cell-based bioengineered products for injured tissue. In this study, we investigated the mesenchymal/epithelial interactions of cultured MSCs in comparison to cultured fibroblasts on epidermal proliferation, differentiation, and extracellular matrix (ECM) protein expression using a de-epidermalized dermis (DED) skin model. We also studied whether MSCs can transdifferentiate to keratinocytes using the same model. Keratinocytes were cultured on unseeded DED or DED populated with fibroblasts or MSCs at an air-liquid interface to induce epidermal differentiation. Fibroblasts or MSCs were also seeded on the papillary surface of the DED alone or on the reticular surface. General histology and immunostaining was performed on the skin equivalents to examine the expression of pan keratin (K) (K1, K5, K6, and K18) and protein markers for epidermal differentiation (K10), hyperproliferation (K6), proliferation (PCNA), ECM component (collagen type IV), and mesenchymal marker (vimentin). Keratinocyte-fibroblast skin model and keratinocyte-MSC skin model both displayed an epidermal phenotype similar to epidermis in vivo. Positive expression of proliferation, differentiation and ECM protein markers was observed. MSCs failed to adopt an epithelial phenotype in the DED skin model. Our findings highlight the potential use of MSCs in bioengineered tissue for the treatment of wounds.

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La piel tiene una función primordial en el control de la integridad del medio interno. En consecuencia, su pérdida en proporciones importantes como aquellas que ocurren en las perdidas traumáticas, cirugías reconstructivas, cirugías oncológicas y grandes quemados, es factor predisponente a complicaciones. En las últimas décadas se han desarrollado diversos métodos que permiten remplazar los principales componentes de la piel. Es así como el tejido dérmico ha sido homologado mediante sustitutos a base de biopolímeros de origen animal. Los equivalentes dérmicos le confieren resistencia mecánica a los injertos y gradualmente facilitan su colonización y reemplazo por fibroblastos y células endoteliales del paciente. La matriz dérmica es un biomaterial que ha sido utilizado por la cirugía plástica, con el propósito de reconstruir en superficie o volumen un tejido que ha sido afectado y que presenta alteraciones en su morfología. Se presenta una revisión y análisis de un ensayo clínico multicéntrico de los pacientes donde se efectuaron 336 biopsias en serie de 131 pacientes participantes, en un lapso de 7 días a 2 años post-aplicación del producto. Se obtiene como resultado que la matriz de regeneración dérmica fue bien tolerada, no hubo notificaciones de respuestas inmunológicas o histológicas con importancia clínica a la implantación del producto. En las evaluaciones clínicas no hubo notificaciones de rechazo a la matriz. Además se recopilaron datos sobre la colonización o infección de las heridas. Las consecuencias de una infección en los lugares tratados con la matriz incluyen pérdida parcial o total de absorción del producto(AU)

The skin has a major role in controlling the integrity of the internal environment. Consequently, their loss in major proportions as those occurring in traumatic losses, reconstructive surgery, cancer surgery and severe burns, is a predisposing factor for complications. In the last decades various methods have been developed that allow replacing the main components in the skin. Thus the dermal tissue has been approved by biopolymers based substitutes animal. Dermal equivalents confer mechanical strength to the grafts and gradually facilitate colonization and replacement by fibroblasts and endothelial cells of the patient. Dermal matrix is a biomaterial that has been used for plastic surgery, for the purpose of reconstructing or surface tissue that volume has been affected and having alterations in morphology. A review and analysis of a multicenter clinical trial of 336 patients where biopsies were performed in series of 131 patients participating in a span of 7 days to 2 years post- spraying. As result the dermal regeneration matrix was well tolerated, no notifications immune responses or clinically significant histological to implantation of the device. In no clinical assessments of rejection notices to the matrix. Also collected data on the colonization or infection of wounds. The consequences of infection sites treated with the matrix include partial or total loss of absorption(AU)

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Skin, together with its appendages, forms an organ with several defensive roles; among them it acts as a barrier, which is one of its very important protective functions. There has been increased interest in studying the effects of age on these functions. There are different intensities and timing involved in this process and also differences between men and women, all relating to skin structure. We review the current knowledge of the skin as a barrier in neonates and in the elderly in an attempt to explain the changes that occur with aging.

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