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Critical bone defects are the most difficult challenges in the area of tissue repair. Polycaprolactone (PCL) scaffolds, associated with hydroxyapatite (HA) and tricalcium phosphate (TCP), are reported to have an enhanced bioactivity. Moreover, the use of electrical stimulation (ES) has overcome the lack of bioelectricity at the bone defect site and compensated the endogenous electrical signals. Such treatments could modulate cells and tissue signaling pathways. However, there is no study investigating the effects of ES and bioceramic composite scaffolds on bone tissue formation, particularly in the view of cell signaling pathway. This study aims to investigate the application of HA/TCP composite scaffolds and ES and their effects on the Wingless-related integration site (Wnt) pathway in critical bone repair. Critical bone defects (25 mm2) were performed in rats, which were divided into four groups: PCL, PCL + ES, HA/TCP and HA/TCP + ES. The scaffolds were grafted at the defect site and applied with the ES application twice a week using 10 µA of current for 5 min. Bone samples were collected for histomorphometry, immunohistochemistry and molecular analysis. At the Wnt canonical pathway, HA/TCP and HA/TCP + ES groups showed higher Wnt1 and ß-catenin gene expression levels, especially HA/TCP. Moreover, HA/TCP + ES presented higher Runx2, Osterix and Bmp-2 levels. At the Wnt non-canonical pathway, HA/TCP group showed higher voltage-gated calcium channel (Vgcc), calmodulin-dependent protein kinase II, and Wnt5a genes expression, while HA/TCP + ES presented higher protein expression of VGCC and calmodulin (CaM) at the same period. The decrease in sclerostin and osteopontin genes expressions and the lower bone sialoprotein II in the HA/TCP + ES group may be related to the early bone remodeling. This study shows that the use of ES modulated the Wnt pathways and accelerated the osteogenesis with improved tissue maturation.

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The literature has shown the beneficial effects of microcurrent (MC) therapy on tissue repair. We investigated if the application of MC at 10 µA/90 s could modulate the expression of remodeling genes transforming growth factor beta (Tgfb), connective tissue growth factor (Ctgf), insulin-like growth factor 1 (Igf1), tenascin C (Tnc), Fibronectin (Fn1), Scleraxis (Scx), Fibromodulin (Fmod) and tenomodulin in NIH/3T3 fibroblasts in a wound healing assay. The cell migration was analyzed between days 0 and 4 in both fibroblasts (F) and fibroblasts + MC (F+MC) groups. On the 4th day, cell viability and gene expression were also analyzed after daily MC application. Higher expression of Ctgf and lower expression of Tnc and Fmod, respectively, were observed in the F+MC group in relation to F group (p < 0.05), and no difference was observed between the groups for the genes Tgfb, Fn1 and Scx. In cell migration, a higher number of cells in the scratch region was observed in group F+MC (p < 0.05) compared to group F on the 4th day, and the cell viability assay showed no difference between the groups. In conclusion, MC therapy at an intensity/time of 10 µA/90 s with 4 daily applications did not affect cell viability, stimulated fibroblasts migration with the involvement of Ctgf, and reduced the Tnc and Fmod expression.

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Objetivo: conhecer a eficácia do uso da microcorrente nas úlceras por pressão, sinalizando os benefícios deste tratamento para o cliente. Métodos: Trata-se de um estudo de atualização de caráter exploratório baseado em leitura corrente e periódicos científicos publicados no Scientific Eletronic Library Online (Scielo), Biblioteca Digital da Universidade de São Paulo (USP) e Revista Eletrônica Quadrimestral de Enfermaria. Resultados: Verificou-se que o uso da microcorrente é um recurso terapêutico que constitui um equipamento de grande benefício quanto ao tratamento das úlceras por pressão, vez que o processo de cura é agilizado e os custos financeiros para o setor hospitalar são minimizados, otimizando o processo de enfermagem. Conclusão: Nesta abordagem teremos melhores respostas para os cuidados de enfermagem, otimizando o tempo da assistência e da hospitalização do paciente em sua condição enfermo motivada pelas escaras.

Objective: to know the effectiveness of the use of microcurrent in pressure ulcers, indicating the benefits of this treatment to the client. Method: This is an exploratory study based on updated scientific current and periodic reading published in the Scientific Electronic Library Online (Scielo), Digital Library of the USP and Electronic Journal quarterly Ward. Results: It was found that the use of microcurrent is a therapeutic resource that is a major benefit to the treatment of pressure ulcers, since the curing process is streamlined and the financial costs for the hospital sector are minimized optimizing the nursing process. Conclusion: In this approach we will have better answers for nursing care optimizing the time of care and patient hospitalization in his ailing condition driven by scabs.

Objetivo: conocer la eficacia de la utilización de micro corriente en las úlceras por presión, indicando los beneficios de este tratamiento para el cliente. Métodos: Se trata de un estudio exploratorio basado en actualización lectura actual y periódica científica publicada en El Scientific Electronic Library Online (Scielo), la Biblioteca Digital de la USP y Diario electrónico trimestral Ward. Resultados: Se encontro que el uso de micro corriente es un recurso terapéutico que es un beneficio importante del producto y el tratamiento de las úlceras por presión, ya que el proceso de curado es aerodinámico y los costos financieros para el sector hospitalario se minimizan optimización el proceso de enfermería. Conclusión: En este enfoque vamos a tenermejores respuestas para la atención de enfermería optimizando el tiempo de atención y hospitalización del paciente en su condición de enfermo impulsado por costras.

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OBJECTIVE: This study evaluated the effects of a low-intensity electric current on tissue reorganization during experimental orthodontic tooth movement. MATERIALS AND METHODS: Thirty-two animals were divided into two groups evaluated on days 3 and 7: OTM-orthodontic tooth movement and OTM + MC-orthodontic tooth movement and microcurrent application (10 µA/5 min). The samples were processed for histological, morphometric, and Western blotting analysis. RESULTS: Analysis of the periodontal ligament (PL) showed a significantly smaller number of granulocytes in the OTM + MC group on day 7.The number of fibroblasts was significantly higher in the OTM + MC group on days 3 and 7. The area of birefringent collagen fibers was more organized in the OTM + MC group on days 3 and 7. The number of blood vessels was significantly higher in the OTM + MC group on day 7. Microcurrent application significantly increased the number of osteoclasts in the compression region of the PL. In the OTM + MC group on day 7 of tooth movement, the expression of TGF-ß1 and VEGF was significantly reduced whereas the expression of bFGF was increased in PL. CONCLUSIONS: Electrical stimulation enhances tissue responses, reducing the number of granulocytes and increasing the number of fibroblasts, blood vessels, and osteoclasts and modulates the expression of TGF-ß1, VEFG, and bFGF. CLINICAL RELEVANCE: This technique is used in many areas of medicine, but poorly explored in dentistry and orthodontics. This treatment is cheap and non-invasive and can be applied by own orthodontist, and it can improve the treatment with a faster and safe tooth movement, without pain.

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Introdução: A cicatrização de feridas é um processo dinâmico que envolve vários elementos celulares com propósito de restabelecer a funcionalidade do tecido lesado, muitos fatores podem interferir neste processo tornando-o complexo. O laser e a microcorrente são modalidades terapêuticas que otimizam o processo de reparo, porém são estudadas isoladas. Objetivo: Investigar a eficácia da associação da fototerapia (laser, GaAlAs, λ 656±5 nm) com a eletroterapia (microcorrente) na cicatrização por segunda intenção em ratos. Método: Foram utilizados 15 ratos submetidos à lesão dorsal direita com 8 mm de diâmetro divididos em três grupos (n=5), nominados de GC (controle), G2 (laser +30µA) e G3 (laser +160 µA). Para análises histopatológicas foi determinado p≤0,05. Resultados: A análise estatística revelou que a área de colágeno apresenta-se estatisticamente superior nos grupos tratados (G2 e G3) quando comparados com o grupo controle. Conclusão: A associação das modalidades induz ao aumento do colágeno na fase inicial do reparo tecidual.

Introduction: Wound healing is a dynamic process that involves multiple cellular elements with the purpose of restoring the functionality of the injured tissue. Many factors can interfere with this process, making it complex. Laser and microcurrent are therapeutic strategies that optimize the repair process, but have been studied in isolation. Objective: To investigate the efficacy of combining phototherapy (laser, GaAlAs, λ 656±5 nm) with electrotherapy (microcurrent) on second intention healing in rats. Methods: We used 15 rats with 8 mm in diameter lesions in the right dorsal. The rats were divided into three groups (n = 5): the CG (control group), G2 (laser+30µA) and G3 (laser +160µA). For histopathological analysis p ≤ 0.05 was determined. Results: Statistical analysis revealed that the area of collagen was statistically higher in the treated groups (G2 and G3) compared with the control group. Conclusion: A combination of methods induces increased collagen in the initial phase of tissue repair.

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The aim of this study was to analyse the effects of microcurrent and gold nanoparticles on oxidative stress parameters and the mitochondrial respiratory chain in the healing of skin wounds. Thirty 60-day old male Wistar rats (250-300 g) were divided into five groups (N=6): Control; Burn wounds; Microcurrent (MIC); Gold nanoparticle gel (GNP gel) and Microcurrent+Gold nanoparticle gel (MIC+GNP gel). The microcurrent treatment was applied for five consecutive days at a dose of 300 µA. The results demonstrate a significant decrease in the activity of complexes I, II-III and IV in the Burn Wounds group compared to the control, and the MIC+GNP gel group was able to reverse this inhibition in complexes I, III and IV. Furthermore, a significant reduction in oxidative damage parameters and a significant increase in the levels of antioxidant defence enzymes were induced in the MIC+GNP gel group compared to the Burn Wounds group. The data strongly indicate that the group receiving treatment with MIC+GNP gel had improved mitochondrial functioning and oxidative stress parameters, which contributed to tissue repair.

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