996 resultados para Célula de sertoli


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Matrix proteins play important roles in tissue morphogenesis. We have studied the expression of genes encoding the related SIBLING glycoproteins osteopontin (OPN), bone sialoprotein (BSP), and dentin matrix protein (DMP) during the development of male and female gonads during mouse embryogenesis. Opn mRNA was expressed specifically by Sertoli cells of the developing testis cords, in the mesonephric tubules of both sexes, and, transiently, in the Mullerian ducts of both sexes, as determined by whole-mount and section in situ hybridization. OPN protein was detected in the cytoplasm of Sertoli cells and luminal cells of the mesonephric tubules, with small amounts associated with the plasma membrane of germ cells. We found no defects in developing testes of Opn-/- mice using a range of cell type-specific markers, suggesting that other SIBLING proteins may function in testis development. Dmp and Bsp mRNA was also expressed in the developing testis cords, supporting the view that all three SIBLING proteins may contribute to testis differentiation. (c) 2005 Wiley-Liss, Inc.

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The gene encoding the matricellular protein secreted protein, acidic and rich in cysteine (SPARC) was identified in a screen for genes expressed sex-specifically during mouse gonad development, as being strongly upregulated in the male gonad from very early in testis development. We present here a detailed analysis of SPARC gene and protein expression during testis development, from 11.5 to 15.5 days post coitum (dpc). Section in situ hybridization analysis revealed that SPARC mRNA is expressed by the Sertoli cells in the testis cords and the fetal Leydig cells, found within the interstitial space between the testis cords. Immunodetection with anti-SPARC antibody showed that the protein was located inside the testis cords, within the cytoplasm of Sertoli and germ cells. In the interstitium, SPARC was present intracellularly within the Leydig cells. The internalization of SPARC in Sertoli, Leydig, and germ cells suggests that it plays an intracellular regulatory role in these cell types during fetal testis development.

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This thesis develops a new technique for composite microstructures projects by the Topology Optimization process, in order to maximize rigidity, making use of Deformation Energy Method and using a refining scheme h-adaptative to obtain a better defining the topological contours of the microstructure. This is done by distributing materials optimally in a region of pre-established project named as Cell Base. In this paper, the Finite Element Method is used to describe the field and for government equation solution. The mesh is refined iteratively refining so that the Finite Element Mesh is made on all the elements which represent solid materials, and all empty elements containing at least one node in a solid material region. The Finite Element Method chosen for the model is the linear triangular three nodes. As for the resolution of the nonlinear programming problem with constraints we were used Augmented Lagrangian method, and a minimization algorithm based on the direction of the Quasi-Newton type and Armijo-Wolfe conditions assisting in the lowering process. The Cell Base that represents the composite is found from the equivalence between a fictional material and a preescribe material, distributed optimally in the project area. The use of the strain energy method is justified for providing a lower computational cost due to a simpler formulation than traditional homogenization method. The results are presented prescription with change, in displacement with change, in volume restriction and from various initial values of relative densities.

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O trabalho apresentado descreve todo o processo de conceção e desenvolvimento de um produto, ferramenta e célula de fabrico, realizado numa empresa de moldes situada na zona da Marinha Grande e denominada por Moldes RP – Indústria Moldes, Sociedade Unipessoal, Lda. Com o desenvolvimento deste novo produto, a empresa pretende atingir novos mercados, alargando a sua cadeia de valor a jusante do fabrico de moldes, integrando a componente de moldação por injeção e sopro, como forma de cimentar a sua posição no mercado global e assumir a conceção e desenvolvimentos de produtos como um eixo estratégico de negócios. Uma das formas de despoletar processos de desenvolvimento de produtos reside na identificação de oportunidades. Neste âmbito, e no respeitante ao produto em foco neste trabalho, verifica-se uma tendência para a proibição de utilização de copos de vidro em espaços públicos, nomeadamente concertos, eventos desportivos e praias, entre outros, o que força os promotores e consumidores a consumir bebidas em copos que respeitem estas condições.Neste contexto, foi identificada como oportunidade o desenvolvimento e produção de um copo de formas complexas e que respeite as condições descritas, tendo por base uma metodologia de conceção e desenvolvimento de produto eficaz. Para tal, o processo adotado como suporte ao desenvolvimento deste produto envolveu, desde os conceitos iniciais de identificação da ideia, pesquisa do estado da arte, análise do meio envolvente e a identificação de vantagens competitivas, até à definição clara de requisitos do produto para a geração do modelo. Complementarmente, e ao nível da produção do produto desenvolvido foi desenvolvida uma tecnologia que permite a obtenção do produto idealizado, através da integração da moldação por injeção sobreposta e moldação por sopro. De destacar que este desenvolvimento culminou num pedido de patente. Por último, e tendo em consideração a análise da viabilidade financeira do produto e processo de produção, é ainda efetuada uma estimativa inicial do custo do produto e o cálculo final do produto tendo em conta as condicionantes relativas ao processo de fabrico.

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Here we describe the case of a 19-year-old woman with a poorly differentiated ovarian Sertoli-Leydig cell tumor and an elevated serum alphafetoprotein level. The patient presented with diffuse abdominal pain and bloating. Physical examination, ultrasound, and magnetic resonance imaging revealed a right ovarian tumor that was histopathologically diagnosed as a poorly differentiated Sertoli-Leydig cell tumor with heterologous elements. Her alpha-fetoprotein serum level was undetectable after tumor resection. Sertoli-Leydig cell tumors are rare sex cord-stromal tumors that account for 0.5% of all ovarian neoplasms. Sertoli-Leydig cell tumors tend to be unilateral and occur in women under 30 years of age. Although they are the most common virilizing tumor of the ovary, about 60% are endocrineinactive tumors. Elevated serum levels of alpha-fetoprotein are rarely associated with Sertoli-Leydig cell tumors, with only approximately 30 such cases previously reported in the literature. The differential diagnosis should include common alpha-fetoprotein-producing ovarian entities such as germ cell tumors, as well as other non-germ cell tumors that have been rarely reported to produce this tumor marker.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2015.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2015.

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Bogotá (Colombia): Universidad de La Salle. Facultad de Ciencias Agropecuarias. Maestría en Ciencias Veterinarias

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Background: Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs) self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. Objective: This study investigated the role of luekemia inhibitory factor (LIF) on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. Materials and Methods: SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Results: Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05). Conclusion: Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment.

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Universidade Estadual de Campinas . Faculdade de Educação Física