Navegando por Palavras-chave "Regeneration"

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    Calcium phosphate fibers coated with collagen: in vivo evaluation of the effects on bone repair
    (Cadernos Saude Publica, 2016) Ueno, Fabio Roberto [UNIFESP]; Kido, Hueliton Wilian [UNIFESP]; Granito, Renata Neves [UNIFESP]; Gabbai-Armelin, Paulo Roberto [UNIFESP]; Magri, Angela Maria Paiva [UNIFESP]; Fernandes, Kelly Rossetti [UNIFESP]; Silva, Antonio Carlos da; Braga, Francisco José Correa; Renno, Ana Claudia Muniz [UNIFESP]
    The aim of this study was to assess the characteristics of the CaP/Col composites, in powder and fiber form, via scanning electron microscopy (SEM), pH and calcium release evaluation after immersion in SBF and to evaluate the performance of these materials on the bone repair process in a tibial bone defect model. For this, four different formulations (CaP powder -CaPp, CaP powder with collagen -CaPp/Col, CaP fibers - CaPf and CaP fibers with collagen - CaPf/Col) were developed. SEM images indicated that both material forms were successfully coated with collagen and that CaPp and CaPf presented HCA precursor crystals on their surface. Although presenting different forms, FTIR analysis indicated that CaPp and CaPf maintained the characteristic peaks for this class of material. Additionally, the calcium assay study demonstrated a higher Ca uptake for CaPp compared to CaPf for up to 5 days. Furthermore, pH measurements revealed that the collagen coating prevented the acidification of the medium, leading to higher pH values for CaPp/Col and CaPf/Col. The histological analysis showed that CaPf/Col demonstrated a higher amount of newly formed bone in the region of the defect and a reduced presence of material. In summary, the results indicated that the fibrous CaP enriched with the organic part (collagen) glassy scaffold presented good degradability and bone-forming properties and also supported Runx2 and RANKL expression. These results show that the present CaP/Col fibrous composite may be used as a bone graft for inducing bone repair.
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    Caracterização da regeneração, inflamação e estresse oxidativo no músculo de modelo experimental para distrofia muscular de Duchenne com fenótipo exacerbado pelo exercício
    (Universidade Federal de São Paulo, 2021-05-12) Lazzarin, Mariana Cruz [UNIFESP]; De Oliveira, Flavia [UNIFESP]; http://lattes.cnpq.br/3387760393535776; http://lattes.cnpq.br/1579497511371132; Universidade Federal de São Paulo (UNIFESP)
    Introdução: A distrofia muscular de Duchenne é uma doença caracterizada por necrose muscular progressiva. O avanço das intervenções terapêuticas e das terapias genéticas tem trazido esperanças quanto à manutenção da funcionalidade motora mesmo em estágios mais tardios da doença. Entretanto, um grande desafio na prescrição de exercícios na reabilitação física para esses pacientes é a ausência de um perfil abrangente da resposta do músculo distrófico ao exercício. Dessa forma, o objetivo desse trabalho foi compreender, em camundongos mdx com fenótipo exacerbado pelo exercício, parâmetros relacionados à regeneração muscular, à inflamação e ao estresse oxidativo. Materiais e métodos: Camundongos C57BL/10 e C57BL/10-DMDmdx, com seis meses de vida, distribuídos em três grupos (n=10 cada): Controle, Mdx e Mdx+Exercício. O protocolo de corrida em declive foi de sete semanas, com frequência de cinco vezes na semana, a uma velocidade máxima particular para cada animal durante 60 minutos. Após eutanásia, o m. gastrocnêmio foi dissecado e realizou-se as análises: histopatológica; imunoistoquímica para marcadores de regeneração muscular (MyoD e Miogenina), de inflamação (COX-2) e para estresse oxidativo (8-OHdG); expressão de genes (qPCR) de NF-kB e NADP(H) Oxidase 2. Resultados: O grupo Mdx+Exercício apresentou a histopatologia do m. gastrocnêmio alterada pela corrida em declive, com maior incidência de fibrose endomisial e menor porcentagem de área de mionecrose. A análise imunoistoquímica revelou aumento da imunoexpressão de Miogenina no grupo Mdx+Exercício, mesmo não influenciando a expressão de MyoD; menor imunoexpressão do 8-OHdG no grupo Mdx e alterou a região histopatológica com imunoexpressão da COX-2. No grupo Mdx, a COX-2 estava relacionada com áreas de regeneração e infiltrado inflamatório, enquanto que no grupo Mdx+Exercício estava associado a regiões de fibrose muscular. Além disso, o exercício não influenciou a expressão gênica de NF-kB, porém aumentou o RNAm de NAD(P)H Oxidase 2. Conclusão: A exacerbação do fenótipo da DMD no músculo gastrocnêmio de camundongos mdx adultos está associada com o aumento da Miogenina, da COX-2 em regiões de fibrose e do 8-OHdG nuclear, bem como da expressão gênica de NAD(P)H Oxidase 2.
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    Caracterização in vitro de neuroesferas e seu potencial de regeneração na doença de alzheimer e lesão por stab wound
    (Universidade Federal de São Paulo (UNIFESP), 2016-03-06) Paiva, Daisylea de Souza [UNIFESP]; Monteiro, Beatriz de Oliveira [UNIFESP]; http://lattes.cnpq.br/0245964878412260; http://lattes.cnpq.br/3693514872706694; Universidade Federal de São Paulo (UNIFESP)
    Objetctive: verify the role of neural stem cells (NSC) in three different aspects: in vitro behaviour, use in memory repair in transgenic animals for Alzheimer's Disease (DA, APPswe/PS1dE9) following transplantation, and expression of proteins related to injury response. Methods: We used in vitro techniques for cell culture of neuroespheres, genome-wide techniques as well as transplantation and behavioral tests. Results: We verified that the APPswe/PS1dE9 transgene affect neurospheres growth rate as well as promoting cellular death. Furthermore, is important to note that differentiated astrocytes from AD animals neurospheres presented hypertrophic morphology, alike the astrocytes from WT animals. Therefore, in this model is possible to identify alterations in NSC as well as soluble amyloid precursor protein secretion during the embrionic stage that can promote proliferation without interfere in the normal development of the animal. When transplanted in transfenic animals for DA, NSCs were able to contribute to neural repair by increasing neurogenesis and secretion of BDNF neurotrophin. Nevertheless there was no effect on memory and habituation in transplanted AD animals. Therefore we demonstrated that even without improving memory at behavioural level, NSC transpantation increased the neurotrophic support in hippocampus and can be responsible for other modifications at molecular level that should be better investigated. From the results of in vitro experiments and to better understand the behaviour of astrocytes in AD we decide to compare the expression pattern of proteins overexpressed at the lesion site of the SW (stab wound). To perform this analysis, we used the genome-wide data from Magdalena Götz's lab to select candidates that could play a role in the stab wound lesion and in AD. Among the top upregulated genes in reactive macroglia (astrocytes and NG2-glia), most of them were related to inflammation and, among these genes we selected four candidates (Osteopontin, CD68 and Galectin-1 and -3). We verified that although they were overexpressed in reactive macroglia after SW injury, the same cells do not express these proteins in AD animals. Whereby SW is an accute injury that is healed within few weeks, we assumed that the downregulation of these proteins could be related to the disease chronicity. Conclusion: By evaluating the in vitro features and role in neurodegeneration processes, we verified that when transplanted, NSC secrete factors that increase the neurotrophic support and during development can play a role in compensating cell death in AD animals. However, in old AD animals macroglial cells do not express proteins that could assist lesion resolution. This work offers insights about the role of NSC and macroglia in Alzheimer's disease.
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    Histological changes underlying bupivacaine's effect on extra ocular muscle
    (Academic Press Ltd- Elsevier Science Ltd, 2018) Hopker, Luisa Moreira [UNIFESP]; Neves, Juliana de Carvalho; Nascimento, Daiane Jaqueline; Campos, Eliene Dutra; Mendonca, Tomas Scalamandre [UNIFESP]; Zanoteli, Edmar; Allemann, Norma [UNIFESP]
    To determine the changes in the cross-sectional area (CSA) of myofibers and their subtype distribution based on the myosin isoform expression after bupivacaine (BUP) injection in the EOM of rabbits and help the understanding of strabismus correction after BUP injection in the clinical practice. A total of 32 rabbits received 0.3 mL of 1.5% BUP in the superior rectus muscle (SR) of the right eye (OD) and were sacrificed at days 7, 28, 60, and 92. Additional eight untouched rabbits were included as controls. Hematoxylin and eosin staining was performed, and ImageJ software was used to measure CSA. Immunohistochemical analysis was performed to analyze the proportion of myofibers positive for myosin types 1 (slow), 2 (fast) and embryonic. Myofiber area measurement decreased 7 days after BUP injection [SR, 1271 +/- 412 mu m(2) (control) to 909 +/- 255 mu m(2) (day 7)] after BUP injection, followed by an increasing trend after 28 days and normalization after 92 days [SR
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    Participação da via de sinalização WNT/β-catenina na desdiferenciação de astrócitos e resposta à lesão cerebral
    (Universidade Federal de São Paulo (UNIFESP), 2017-12-21) Pinto, Agnes Araujo Sardinha [UNIFESP]; Porcionatto, Marimelia [UNIFESP]; http://lattes.cnpq.br/6155537170968904; http://lattes.cnpq.br/9032362908049263; Universidade Federal de São Paulo (UNIFESP)
    Neurogenesis in the central nervous system (CNS) of adult mammals occurs mainly in two restricted and specialized regions of the brain, the subgranular and the subventricular zone. In addition to physiological neurogenesis, there are also stimulating the production of new neural cells in response to a brain injury. The astrocytes also play an important role in the organism's response to lesions in the CNS, participating in the determination of the cellular proliferative activity in the neurogenic regions. Another response of these cells is the of cellular activation, where there may be a transition from a subpopulation of astrocytes to a less differentiated state. This transition is characterized by changes in phenotype and entry into a proliferative state suggesting the occurrence of dedifferentiation, in which the asth- neural stem cell characteristics. Little is known about the functions reactive astrocytes can perform, their effects on the other cells of the CNS and their contribution to tissue regeneration. Therefore, the investigation of the factors involved in the process of astrocyte activation becomes relevant in the sense of " identify possible therapeutic targets to optimize the generation of new cells multipotent at the site of the injury, which would allow obstacles to be and cell migration from the neurogenic niches. Given the importance of elucidate the pathways involved in astrocytic activation, this study sought to investigate the possible participation of the Wntll3-catenin signaling pathway in this process. For Therefore, we subjected astrocytes in primary culture to the model of mechanical vitro and to treatment with Wnt 3a protein or its inhibitor (Dickkopf-1). As a result, treatment with the pathway inhibitor reduced the ability to of astrocyte derived neurospheres. In the in vivo model, we also observed increased expression of Wnt 3a three days after injury. However, inhibition of the in this same animal model did not cause changes in behavior proliferation and expression of astrocyte activation markers. Considering the results presented here, we conclude that the WntII-catenin pathway is required, but not sufficient, to induce the acquisition of stem cell phenotype by reactive astrocytes, suggesting that other factors, not studied in this work, are necessary for the process to take place.
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    A polyp from nothing: The extreme regeneration capacity of the Atlantic invasive sun corals Tubastraea coccinea and T-tagusensis (Anthozoa, Scleractinia)
    (Elsevier Science Bv, 2018) Luz, Bruna Louise Pereira; Capel, Kátia Cristina Cruz; Zilberberg, Carla; Flores, Augusto Alberto Valero; Migotto, Álvaro Esteves; Kitahara, Marcelo Visentini [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The azooxanthellate sun corals Tubastraea coccinea and T. tagusensis have invaded and dramatically changed rocky reef habitats along the Brazilian coast. Management of invaded areas has brought discussions on its potential negative effects regarding species dispersal, including those related to fragmentation. Although fragmentation has been observed in unmanaged localities, here we experimentally tested the sun coral ability to regenerate from undifferentiated coral tissue to fully functional polyps in response to differences in food supply, temperature, and fragment size. In general, survival and successful regeneration were high and markedly similar for both species. However, while percent of tissue retraction/reorganization (a proxy of metabolic cost) responded to fragment size and temperature, mouth development was faster in fed fragments. Together, our findings indicate that sun coral fragments may regenerate at temperatures that lead to extensive bleaching in native scleractinians that harbor Symbiodinium. Although no doubts remain about the necessity and efficacy of the management of invasive Tubastraea spp., recovery of undifferentiated coral tissue to fully functional polyps may contribute to their invasion success and should be taken into account during management efforts.
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    Regeneração de nervo periférico após anastomose término-lateral, com manutenção do epineuro, em ratos
    (Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2001-09-01) Rosseto, Marcelo; Fagundes, Djalma José [UNIFESP]; Taha, Murched Omar [UNIFESP]; Souza, Heitor Soares de [UNIFESP]; Aydos, Ricardo Dutra; Guimarães, Ricardo Bezerra; Novo, Neil Ferreira [UNIFESP]; Juliano, Yara [UNIFESP]; Universidade Federal de Mato Grosso do Sul Departamento de Clínica Cirúrgica; Universidade Federal de São Paulo (UNIFESP); Santa Casa de Campo Grande Serviço de Residência Médica em Cirurgia Geral; Universidade Federal do Mato Grosso do Sul DCC; Universidade Federal do Mato Grosso do Sul
    Reinervation techniques can be done by termino-terminal or end-to-side anastomosis, and it has been extensively studied. The end-to-side anastomosis hasn t been used often compared to the termino-terminal technique, because the former is contested by some authors regarded the reinervation chances when the integrity of the epineuro is maintened. Therefore, due to the divergenses, the authors decide to study the effects of epineuro in the nervous regeneration in the end-to-side anastomosis technique. In this study, 20 wistar adults rats were used, distributed in two groups (A and B). In the A Group, 10 rats were submited to the section of fibular nerve in the right pelvic limb and fixation of this nerve to the muscle; in the left pelvic limb, section of the fibular nerve was done with lateral anastomosis with the fibular nerve. In Group B, the procedures were indentical to the A group, with the only difference that the limbs were exchanged. In the 90 th post operative day a biopsy was performed in each fibular nerve in order to histological analisys in optical microscope, where the reinervation was object of study. The reinervation was found happened, showing that the preservation of epineuro didn t avoid the axonal regeneration.
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    Uso de matrizes de rins descelularizadas e repopulados com células tronco estromais mesenquimais da medula óssea
    (Universidade Federal de São Paulo (UNIFESP), 2017-06-29) Cruz, Edgar Ferreira da [UNIFESP]; Schor, Nestor [UNIFESP]; http://lattes.cnpq.br/8276708741672261; http://lattes.cnpq.br/9551097252315213; Universidade Federal de São Paulo (UNIFESP)
    Chronic kidney disease is a pandemic health problem worldwide. The number of people affected by this disease grows exponentially. Studies shows the bioengineered organs associated to stem cells as a possibility of new strategies of development to treatment of chronic kidney disease. In this research, we developed a platform of understand steps of regeneration kidney tissues, using extracellular matrix scaffold from different species with mesenchymal stem cell from bone marrow and umbilical cord human stem cells. Our results showed the decellularization process, the repopulation of the ECM scaffold in differents time points of tissue culture and some biological steps of this “re” construction