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Introducción: Las quemaduras son un trauma frecuente de ocurrencia en todo el mundo, que ha experimentado importantes aumentos de sobrevida. Su manejo requiere la reposición de la barrera cutánea, lo que se logra en la mayoría de los casos con el uso de injertos dermo-epidérmicos. Sin embargo, existen algunas veces lesiones complejas que no logran sanar mediante injertos, arriesgando la funcionalidad o vitalidad del área comprometida, que requerirán reparaciones complejas con el uso de colgajos microqui- rúrgicos (CM). Metodología: Estudio descriptivo retrospectivo en que incluimos todos los pacientes gran quemados agudos admitidos en Hospital de Urgencia de la Asistencia Pública, Servicio de Quemados y Rehabilitación, desde abril de 2019 hasta diciembre de 2020 los que fueron manejados con colgajo micro- quirúrgico. Revisión de ficha clínica para obtención de variables demográficas y del procedimiento con análisis de frecuencia de ocurrencia. Resultados: En nuestro período de estudio hubo 376 ingresos y 21 pacientes recibieron 25 CM. La mayoría hombres (96%), edad promedio 40 años, superficie comprometida promedio 16%, mecanismo más frecuente electricidad (64%) y fuego (32%). La ubicación más frecuente del colgajo fue en extremidades inferiores (64%) y el colgajo más utilizado fue el anterolateral de muslo (80%). Tiempo medio a reconstrucción fueron 40 días, no hubo pérdida total del colgajo. Discusión: se realizó un CM en 5,6% de nuestros ingresos, la mayoría durante el intervalo primario tardío, sin pérdidas totales. Estos resultados representan la consolidación de la técnica que permite su uso en el paciente gran quemado durante su etapa aguda, permitiendo coberturas complejas y manteniendo riesgo quirúrgico y tasa de complicaciones adecuada con enfoque en rehabilitación precoz.

Introduction: Burns are the fourth most common trauma. Microsurgery has evolved as a valuable tool in the acute setting allowing early closure of complex wounds in order to avoid infection, maintain function or even for limb salvage in one stage reconstruction. We present our experience at our burn center in Chile. Method: We performed a retrospective analysis of all major burn patients admitted in the National Burn Center in Chile who received a microsurgical flap in the period between April 2019 to December 2020. Results: A total of 21 patients had 25 free flaps. All patients but one were male (96%), mean age 40 years (range 20-69 years). Total body surface area means 16% (range 1-64%). Most of the injuries were caused by high voltage electricity (64%) and fire (32%). 64% were performed in lower limbs and 36% in upper limbs. In 80% of the cases, anterolateral thing flap was chosen. Mean time to reconstruction was 40 days. We didn't experience a total flap lost in this series. Discussion: In the acute phase microsurgery proved to be safe and feasible albeit a small surgical indication. We performed a flap in 5.6% of our admissions, mostly during late primary interval with no flaps lost. Our results acknowledge the consolidation of the technique for its use in the acutely burned setting, allowing complex coverage while maintaining the surgical risk and an internationally acceptable rate of losses and complications.

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Este relato de caso aborda o curso clínico de um envenenamento botrópico ocorrido no município de Jarinu, SP, no ano de 2021. O paciente necessitou de fasciotomia em membro superior após síndrome compartimental aguda com enxertia dermoepidérmica em um segundo momento cirúrgico. No pós-operatório tardio, o paciente evoluiu com retração, necessitando de reabordagem cirúrgica com correção de retração de membro superior esquerdo. Discute-se a gravidade do acidente ofídico, efeitos do veneno nos tecidos, complicações, síndrome compartimental aguda, indicação e técnica da fasciotomia descompressiva com base na literatura.

This case study examines the clinical course of a Bothrops snakebite poisoning that occurred in Jarinu, São Paulo, Brazil, in 2021. The patient required a fasciotomy in the upper limb due to acute compartment syndrome, followed by a second surgical procedure involving dermo-epidermal grafting. In the late postoperative period, the patient experienced retraction, leading to a subsequent surgical intervention to correct the retraction in the left upper limb. The severity of the snakebite accident, the effects of venom on tissues, complications, acute compartment syndrome, as well as the indications and techniques for decompressive fasciotomy, are discussed based on the available literature.

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ABSTRACT Objective: The objective of this study was to describe a case of cutaneous lichen planus (LP) that appeared following COVID-19 infection. Case description: We report a case of extensive cutaneous classic familial LP in a 4-year-old male child after an asymptomatic serologically confirmed COVID-19 infection. The patient developed intensely itchy, purple, flat-topped papules and plaques, mainly on the dorsal surface of the hands, feet, forearms, and shins. Histopathological examination of the skin biopsy showed vacuolar and apoptotic degeneration of the basal cell layer with a band-like lymphocyte infiltrate at the dermo-epidermal junction and confirmed the diagnosis of LP. Comments: LP could be considered among the differential diagnoses of pediatric post-COVID inflammatory skin lesions, either in the patients recovering from COVID-19 infection or in the suspicious asymptomatic cases in close contact with COVID-19-infected patients.

RESUMO Objetivo: Descrever um caso de líquen plano cutâneo (LP) após infecção por COVID-19. Descrição do caso: Relatamos um caso de LP familiar clássico extenso cutâneo em uma criança de quatro anos de idade após uma infecção por COVID-19 assintomática e sorologicamente confirmada. O paciente desenvolveu pápulas e placas intensamente pruriginosas, roxas e achatadas, principalmente na superfície dorsal das mãos, pés, antebraços e canelas. O exame histopatológico da biópsia de pele mostrou degeneração vacuolar e apoptótica da camada basal com infiltrado de linfócitos em faixa na junção dermoepidérmica e confirmou o diagnóstico de líquen plano. Comentários: O líquen plano pode ser considerado entre os diagnósticos diferenciais de lesões cutâneas inflamatórias pós-COVID pediátricas, tanto em pacientes em recuperação de infecção por COVID-19 quanto em casos assintomáticos suspeitos em contato próximo com pacientes infectados por COVID-19.

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Circular economy, and concerns about environmental waste, is fostering the development of sustainable alternative products in a range of industries. In the dermo-cosmetic field, the market for sustainable anti-aging skincare products has increasingly grown over the last years. The innovation of this work was to develop chitosan films incorporating lemongrass essential oil (LEO) that could potentially be applied as a green cosmetic skin treatment due to their anti-oxidant and antimicrobial properties, using renewable and biodegradable materials. Different concentrations of LEO (i.e., 0.5, 1.0, and 1.5 % w/w) were formulated into chitosan filmogenic matrices, forming skincare bioactive films. Their antioxidant properties and water vapor permeability were strongly governed by the LEO concentration. Chitosan bioactive films containing 0.5 % LEO showed cellular viability over 70 %, while those with 1.5 % LEO had similar antioxidant capacity as NAC (N-acetyl-L-cysteine), used as the positive control to inactivate intracellular reactive oxygen species (ROS) in HaCat cells not treated with H2O2. The developed bioactive films showed activity against Escherichia coli and Staphylococcus aureus. Our LEO-loaded chitosan biofilms may be used as sheet masks with antioxidant and antimicrobial properties for skincare, with high flexibility and selected permeability, and without cytotoxic risks.

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In regions adjacent to the Brazilian Atlantic Forest, Virola oleifera (VO) resin extract has been popularly used for decades as a skin and mucosal healing agent. However, this antioxidant-rich resin has not yet been investigated in wound healing, whose physiological process might also be aggravated by oxidative stress-related diseases (e.g., hypertension/diabetes). Our aim, therefore, was to investigate whether VO resin presents healing effects through an innovative cream for topical applications. For this, adult male Wistar rats were divided into four groups. Then, four 15 mm excisions were performed on the shaved skin. All treatments were applied topically to the wound area daily. At the end of experiments (0, 3rd, and 10th days) macroscopic analysis of wound tissue contraction and histological analysis of inflammatory cell parameters were performed. The group treated with VO cream showed the best wound contraction (15%, p < 0.05) and reduced levels of lipid peroxidation and protein oxidation (118% and 110%, p < 0.05, respectively) compared to the control group. Our results demonstrated the healing capacity of a new formulation prepared with VO, which could be, at least in part, justified by antioxidant mechanisms that contribute to re-epithelialization, becoming a promising dermo-cosmetic for the treatment of wound healing.

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RESUMEN La obesidad y el sobrepeso se definen como una acumulación anormal o excesiva de grasa que puede ser perjudicial para la salud. Es una enfermedad crónica de origen multifactorial, que como consecuencia ocasiona problemas higiénicos, discapacidad funcional y alteración de la calidad de vida. La dermolipectomía abdominal es una técnica quirúrgica que constituye la única opción para el tratamiento de pacientes con panículo adiposo prominente; de esa forma se logra disminuir las complicaciones y se reintegra socialmente al paciente que, a causa del enorme faldón abdominal, estuvo limitado por muchos años. Presentamos el caso de una paciente de 53 años con lipodistrofia abdominal grave, que llegaba a ambos tobillos con afectación cutánea, y discapacidad para realizar actividades diarias, resuelta con dermolipectomía abdominal y resección de 29 kg de tejido dermograso. Se realizará, además, una revisión bibliográfica del tema.

ABSTRACT Overweight and obesity are defined as abnormal or excessive fat accumulation that presents a risk to health. It is a chronic disease caused by multiple factors, which results in hygienic issues, functional disability and impaired quality of life. Abdominal dermolipectomy is the only surgical option for the treatment of patients with prominent panniculus morbidus, thus reducing complications and providing social reintegration for the patient who has been limited for many years due to the enormous abdominal panniculus. We report the case of a 53-year-old female patient with severe abdominal lipodystrophy with coverage of both ankles, skin involvement, and disability to perform daily activities, that was managed with abdominal dermolipectomy and resection of 29 kg of dermo-adipose tissue. Bibliographic research is also presented.

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Abstract Epidermolysis bullosa acquisita is a rare autoimmune disease, characterized by the synthesis of anti-collagen VII autoantibodies, the main component of hemidesmosome anchoring fibrils. The antigen-antibody binding elicits a complex inflammatory response, which culminates in the loss of dermo-epidermal adhesion of the skin and/or mucous membranes. Skin fragility with bullae, erosions, and milia in areas of trauma characterizes the mechanobullous form of the disease. In the inflammatory form of epidermolysis bullosa acquisita, urticarial inflammatory plaques with tense bullae, similar to bullous pemphigoid, or mucosal lesions can determine permanent scars and loss of functionality in the ocular, oral, esophageal, and urogenital regions. Due to the similarity of the clinical findings of epidermolysis bullosa acquisita with other diseases of the pemphigoid group and with porphyria cutanea tarda, the diagnosis is currently confirmed mainly based on the clinical correlation with histopathological findings (pauci-inflammatory subepidermal cleavage or with a neutrophilic infiltrate) and the demonstration of the presence of anti-collagen VII IgG in situ by direct immunofluorescence, or circulating anti-collagen VII IgG through indirect immunofluorescence and/or ELISA. There is no specific therapy for epidermolysis bullosa acquisita and the response to treatment is variable, usually with complete remission in children and a worse prognosis in adults with mucosal involvement. Systemic corticosteroids and immunomodulators (colchicine and dapsone) are alternatives for the treatment of mild forms of the disease, while severe forms require the use of corticosteroid therapy associated with immunosuppressants, intravenous immunoglobulin, and rituximab.

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UV radiation can cause damages, such as erythema, skin photoaging, and carcinogenesis. The adoption of protective measures against sun exposure is essential to prevent these damages, and the interest in using natural substances as an alternative for photoprotection is growing. Thus, hesperetin with antioxidant, anti-inflammatory, and anticancer properties is a promising substance to be used with photochemopreventive action and to protect the skin from damage induced by UV radiation. Therefore, the present study aimed to develop a topical formulation based on AAMVPC gel containing hesperetin and evaluate its photoprotective effect on the skin of rats exposed to UVA-UVB radiation. The animals were submitted to the irradiation protocol UVA-UVB, and at the end, erythema, lipid peroxidation, and activity of the antioxidant enzyme catalase and superoxide dismutase were evaluated. Additionally, it evaluated the activity of myeloperoxidase and histological changes. The formulation presented a rheological and spreadability profile suitable for cutaneous application. In vivo results demonstrated that the topical formulation of AAMVPC gel containing hesperetin at a concentration of 10% protected the skin from damage induced by UVA-UVB radiation, with the absence of erythema, lipid lipoperoxidation, and inflammation (low myeloperoxidase activity), and increased catalase and superoxide dismutase activities. The morphology and architecture of the dermo-epidermal tissue of these animals were like those observed under normal conditions (non-irradiated animals). Thus, the results showed that hesperetin was able to protect the animals' skin against UV radiation-induced skin damage and the protection mechanisms may be related to the antioxidant and anti-inflammatory properties of this natural product.

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Epidermolysis bullosa acquisita is a rare autoimmune disease, characterized by the synthesis of anti-collagen VII autoantibodies, the main component of hemidesmosome anchoring fibrils. The antigen-antibody binding elicits a complex inflammatory response, which culminates in the loss of dermo-epidermal adhesion of the skin and/or mucous membranes. Skin fragility with bullae, erosions, and milia in areas of trauma characterizes the mechanobullous form of the disease. In the inflammatory form of epidermolysis bullosa acquisita, urticarial inflammatory plaques with tense bullae, similar to bullous pemphigoid, or mucosal lesions can determine permanent scars and loss of functionality in the ocular, oral, esophageal, and urogenital regions. Due to the similarity of the clinical findings of epidermolysis bullosa acquisita with other diseases of the pemphigoid group and with porphyria cutanea tarda, the diagnosis is currently confirmed mainly based on the clinical correlation with histopathological findings (pauci-inflammatory subepidermal cleavage or with a neutrophilic infiltrate) and the demonstration of the presence of anti-collagen VII IgG in situ by direct immunofluorescence, or circulating anti-collagen VII IgG through indirect immunofluorescence and/or ELISA. There is no specific therapy for epidermolysis bullosa acquisita and the response to treatment is variable, usually with complete remission in children and a worse prognosis in adults with mucosal involvement. Systemic corticosteroids and immunomodulators (colchicine and dapsone) are alternatives for the treatment of mild forms of the disease, while severe forms require the use of corticosteroid therapy associated with immunosuppressants, intravenous immunoglobulin, and rituximab.

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ABSTRACT: Recessive dystrophic epidermolysis bullosa (RDEB) is a rare genetic condition in which mutations in the type VII collagen gene ( COL7A1 ) lead to decreased expression of this anchoring protein of the skin, causing the loss of stability at the dermo-epidermal junction. Most patients with RDEB experience neuropathic pain and itch due to the development of a small fibre neuropathy, characterised by decreased intraepidermal innervation and thermal hypoaesthesia. To understand the physiopathology of this neuropathy, we used a mouse model of RDEB (Col7a1 flNeo/flNeo ) and performed a detailed characterisation of the somatosensory system. Col7a1 flNeo/flNeo mice showed a decrease in heat sensitivity, an increase in spontaneous scratching, and a significant decrease in intraepidermal nerve fibre density in the hindpaw; these changes were distal because there was no significant loss of unmyelinated or myelinated fibres in the nerve trunk. Of interest, we observed a decrease in axon diameter in both myelinated and unmyelinated fibres. This axonal damage was not associated with inflammation of the dorsal root ganglion or central projection targets at the time of assessment. These results suggest that in RDEB, there is a distal degeneration of axons produced by exclusive damage of small fibres in the epidermis, and in contrast with traumatic and acute neuropathies, it does not induce sustained neuroinflammation. Thus, this animal model emphasizes the importance of a healthy cutaneous environment for maintenance of epidermal innervation and faithfully replicates the pathology in humans, offering the opportunity to use this model in the development of treatments for pain for patients with RDEB.

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El tratamiento de la diástasis abdominal en pacientes con colgajo dermograso no está estandarizado y puede realizarse mediante diferentes técnicas. Presentamos una alternativa para el manejo miniinvasivo de pacientes con diástasis abdominal asociada a colgajo dermograso mediante la combinación de tres procedimientos que denominamos "táctica VER": Vaser® + endoscopia + Renuvion®. Según nuestra experiencia preliminar, la combinación de los 3 procedimientos es segura y efectiva en los casos seleccionados

The treatment of abdominal diastasis in patients with a dermo-fat flap is not standardized and can be performed using different techniques. We present an alternative for the minimally invasive management of patients with abdominal diastasis associated with dermo-fat flap through the combination of three procedures that we call "VER tactic": Vaser® + Endoscopy + Renuvion®. Based on our preliminary experience, the combination of the 3 procedures is safe and effective in selected cases

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Some melanocytic lesions do not present enough clinical and dermoscopic features to allow ruling out a possible melanoma diagnosis. These "doubtful melanocytic lesions" pose a very common and challenging scenario in clinical practice and were selected at this study for reflectance confocal microscopy evaluation and subsequent surgical excision for histopathological diagnosis. The study included 110 lesions and three confocal features were statistically able to distinguish benign melanocytic lesions from melanomas: "peripheral hotspot at dermo-epidermal junction", "nucleated roundish cells at the dermo-epidermal junction" and "sheet of cells". The finding of a peripheral hotspot (atypical cells in 1mm2) at the DEJ is highlighted because has not been previously reported in the literature as a confocal feature related to melanomas.

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This study aimed to report the effects of different doses of ionizing radiation on inflammatory and repair stage of human skin graft adherence in Nude mice wounds. Animals were divided into transplanted with irradiated human skin grafts (IHSG) at 25 and 50 kGy (IHSG 25 kGy; IHSG 50 kGy) and non-IHSG and euthanized on the 3rd, 7th and 21st days after the surgery, by gross and microscopic changes, immunostaining for human type I collagen (Col I) and mouse Col I and Col III and inflammatory cells. We found an effectiveness of human split-thickness graft adherence in mice transplanted with IHSG 25 kGy, as well decrease in dermo-epidermal necrosis and neutrophils, lower loss of skin thickness, epithelization and neo-vascularization. Day 21 post-transplantation with IHSG 25 kGy was observed a well-preserved human skin in the border of the graft, a prominent granulation tissue in an organization by proliferated fibroblasts, Col III deposition and increased B-cells and macrophages. A complete adherence of human skin graft occurred with IHSG 25 kGy. We suggest that the ionizing radiation at 25 kGy mediates inflammation and the repair stage of human skin graft adherence in murine model, thus emerging as a potential tool in healing cutaneous wounds.

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Skin has a preventive role against any damage raised by harmful microorganisms and physical and chemical assaults from the external environment that could affect the body's internal organs. Dermis represents the main section of the skin, and its contribution to skin physiology is critical due to its diverse cellularity, vasculature, and release of molecular mediators involved in the extracellular matrix maintenance and modulation of the immune response. Skin structure and complexity limit the transport of substances, promoting the study of different types of nanoparticles that penetrate the skin layers under different mechanisms intended for skin illness treatments and dermo-cosmetic applications. In this work, we present a detailed morphological description of the dermis in terms of its structures and resident cells. Furthermore, we analyze the role of the dermis in regulating skin homeostasis and its alterations in pathophysiological conditions, highlighting its potential as a therapeutic target. Additionally, we describe the use of nanoparticles for skin illness treatments focused on dermis release and promote the use of metal-organic frameworks (MOFs) as an integrative strategy for skin treatments.

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Facial melanoma presents itself as a brownish macula, being difficult to differentiate it from benign pigmented lesions of the face on clinical examination. Reflectance confocal microscopy (RCM) assists in diagnosing facial lesions in which dermoscopy has limitations, allowing to increase the diagnostic accuracy. The study aimed to analyze the RCM features of pigmented isolated lesions of the face for diagnosing melanoma. Also, we sought to establish the chance of a pigmented lesion on the face being a melanoma using RCM criteria. In this retrospective and prospective study, 105 clinical pigmented lesions on the face underwent RCM, and cytoarchitectural features in the epidermis, the dermo-epidermal junction (DEJ), and dermis were described. For statistical analysis, the exact chi-square test was applied to the RCM criteria. The odds ratio was estimated using univariate logistic regression. Finally, we used the multiple logistic regression method for creating a nomogram to predict the chance of a lesion being a melanoma. After univariate and multivariate logistic regression, atypical round nucleated cells within the epidermis, pagetoid spread, and follicular dendritic cells presented as statistically significant features. Then, a complex nomogram was created to give the chance of a pigmented lesion on the face being a melanoma. The presence of these three features resulted in a 98% probability for melanoma. This study allowed to estimate the diagnosis of melanoma on the face, using RCM, practicable and feasible in the daily routine, through the presence of some RCM nomogram criteria.

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Resumen Objetivo: Mostrar los resultados en el corto y mediano plazo del tratamiento endovascular de angioplastia transluminal percutánea (ATP) con balón en pacientes en estado de isquemia crítica por enfermedad arterial obstructiva infrapoplítea. Materiales y Método: Estudio descriptivo, observacional, retrospectivo. Se incluyeron los pacientes hospitalizados entre 2009 y 2018 por isquemia crítica Fontaine III o IV sometidos a una ATP del territorio infrapoplíteo. Se observó como objetivos primarios la preservación de la extremidad afectada y la mortalidad posoperatoria a un año plazo, y como objetivos secundarios los procedimientos adicionales en pacientes con lesiones o necrosis distales, estadía hospitalaria, complicaciones posoperatorias y necesidad de reintervención. Resultados: Se incluyeron 42 pacientes con un promedio de edad de 66 años (46-82), con importantes comorbilidades. Un 83,3% ingresó en etapa Fontaine IV. En 16 casos se realizó una angioplastia percutánea en más de una arteria. No se colocó stents. Se presentaron complicaciones en 3 pacientes, 2 requirieron una amputación mayor y en otro se debió efectuar un nuevo procedimiento endovascular de rescate. La estadía hospitalaria promedio fue 22 días. No hubo mortalidad precoz posprocedimiento. La mortalidad global a un año fue 9,5%. A todos los pacientes en etapa Fontaine IV se les efectuó algún procedimiento adicional, a 31 una amputación menor, 3 cerraron sus lesiones por segunda intención y en otro se realizó un injerto dermo-epidérmico. De los 35 pacientes con seguimiento, 77% preservó su extremidad a un año. Conclusión: La reparación endovascular mediante una angioplastia percutánea en estos casos es un procedimiento seguro y tiene una alta tasa de preservación de la extremidad inicial a un año de seguimiento.

Aim: Show initial and midterms results of endovascular Percutaneous Transluminal Angioplasty (PTA) in critical limb isquemia (CLI) patients caused by below-the-knee arterial disease. Materials and Method: Observational, descriptive and retrospective study. 42 CLI patients admitted in our hospital from 2009 until 2018 with Fontaine III or IV treated by PTA in infrapopliteal arteries were analyzed, collecting demographic, clinical and surgical characteristics, additional procedures in Fontaine IV, hospital stay, postoperative complications, need of reintervention, limb preservation and mortality with one year follow-up after procedure. Results: 42 patients, average age 66 year-old (46-82), with significant comorbidities. Fontaine IV stage patients were 83.3%. In 16 cases more than one artery was intervened. No stent revascularization was performed. Complications occurred in 3 patients, 2 required major amputation and an urgent endovascular reintervention was required in another. Average hospital stay was 22 days with no post-operative mortality. One-year global mortality was 9.5 One-year follow-up in 35 patients shows that 77% preserved their limb. Conclusión: Percutaneous transluminal angioplasty procedure in this patients has a high rate of limb preservation in a one-year follow-up. There was no post-operative mortality.

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Abstract Lymphocytic thrombophilic arteritis is a recently described entity, histopathologically characterized by lymphocytic vasculitis that affects the arterioles of the dermo-hypodermic junction, associated with deposition of fibrin and a luminal fibrin ring. A 49-year-old female patient presented with achromic maculae and a well-defined ulcer on the medial aspect of the left lower limb. The biopsy showed intense inflammatory infiltrate in the papillary dermis with a predominance of lymphocytes, and medium-caliber vessels surrounded by mononuclear infiltrates in the deep reticular dermis. Masson's trichrome staining showed intense destruction of the muscle layer of the vascular wall and a fibrin ring. Good clinical response was attained with azathioprine. The authors believe that the ulceration might be another clinical presentation or represent an atypical progression of this condition.

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The control of skin permeability to specific substances (e.g., medications, vitamins, and nutrients) through stratum corneum is a challenge. Iontophoresis is an option in spite of the lack of a detailed understanding of the underlying molecular mechanism. In the present work, the simulations concerning application of an external continuous electric field to stratum corneum, in a range of low intensity (0-24 mV nm-1), were carried out using the coarse-grained molecular dynamics approach. Using a set of random seed replicas of the starting configuration, we observed that in the range of electric field intensity of 22-23 mV nm-1, water-rich lipid vesicles were formed in 20% of cases. Pores appeared in the remaining 80%. We argue that lipids undergo fast re-orientations under electric field inducing mechanical instability, which originates the pores. We presented a simple electrostatic model to interpret the results where the mismatch between electrical permittivities of the membrane and external media and the gradient of the local electric field in the membrane surface, govern the time scales and electric fields for vesicle formation. Our results indicate that just 10% difference between electrical permittivities of the membrane and external media decreases 1/6 the minimal time required for vesicle formation. The minimal electric field required decreases 10 times. The control and tunning of formation of biologically compatible vesicles, capable of transporting substances under low-intensity electric fields, has a promising application in fields such as drug therapy and dermo-cosmetics allowing the use of hydrophilic substances in dermal applications.

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Lymphocytic thrombophilic arteritis is a recently described entity, histopathologically characterized by lymphocytic vasculitis that affects the arterioles of the dermo-hypodermic junction, associated with deposition of fibrin and a luminal fibrin ring. A 49-year-old female patient presented with achromic maculae and a well-defined ulcer on the medial aspect of the left lower limb. The biopsy showed intense inflammatory infiltrate in the papillary dermis with a predominance of lymphocytes, and medium-caliber vessels surrounded by mononuclear infiltrates in the deep reticular dermis. Masson's trichrome staining showed intense destruction of the muscle layer of the vascular wall and a fibrin ring. Good clinical response was attained with azathioprine. The authors believe that the ulceration might be another clinical presentation or represent an atypical progression of this condition.

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