24 research outputs found

    Ultrastructural features of agouti (Dasyprocta aguti) preantral follicles cryopreserved using dimethyl sulfoxide, ethylene glycol and propanediol

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    The objective was to develop an efficient protocol for cryopreservation of agouti (Dasyprocta aguti) ovarian tissue. Agouti ovarian fragments were placed, for 10 min, in a solution containing MEM and fetal bovine serum plus 1.5 M dimethyl sulfoxide (DMSO), ethylene glycol (EG) or propanediol (PROH); some of those fragments were subsequently cryopreserved in a programmable freezer. After exposure and/or thawing, all samples were fixed in Carnoy prior to histological analysis. To evaluate ultrastructure, follicles from the control and all cryopreserved treatments were fixed in Karnovsky and processed for transmission electron microscopy. After exposure and freezing, there was a significant decrease in the percentage of morphologically normal preantral follicles in all treatments when compared to the control (92.67 ± 2.79, mean ± SD). However, there were no significant difference when the exposure and freezing procedures were compared using the same cryoprotectant. Moreover, there was no significant difference among cryoprotectants at the time of exposure (DMSO: 64.7 ± 3.8; EG: 70.7 ± 11.2, PROH: 63.3 ± 8.5) or after freezing (DMSO: 60.6 ± 3.6, EG: 64.0 ± 11.9; PROH: 62.0 ± 6.9). However, only follicles frozen with PROH had normal ultrastructure. In conclusion, preantral follicles enclosed in agouti ovarian tissue were successfully cryopreserved using 1.5 M PROH, with satisfactory maintenance of follicle morphology and ultrastructure

    Caracterização estrutural e papel do fator de crescimento derivado de plaquetas (PDGF) na foliculogênese ovariana

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    Background:  :  :      : The platelet-derived growth factor (PDGF) is expressed in a wide variety of cell types, exerts a potent mitogenic role and acts on the growth, differentiation and cell chemotaxis. Studies have shown that during folliculogenesis, PDGF and their receptors are expressed in oocytes, granulosa cells and thecal cells of ovarian follicles at different developmental stages in several species. Although exist many information about its expression sites, as well as about its action in different cells types, the role of PDGF on ovarian folliculogenesis remains understudied. Thus, this article aims to review issues related to PDGF, suggesting the involvement of this mitogenic factor during follicular development. Review: Along this work, it was shown aspects related to structural characterization of PDGF and its receptors, as well as PDGF expression in different cells types, emphasizing its importance to follicular development. PDGF family is composed by four polypeptide chains (each encoded by a different gene), which are synthesized in the form of inactive pro-proteins. After a proteolytic processing, these chains undergo homo or heterodimerization, resulting in five isoforms (PDGF-AA, -BB, -AB, -CC e -DD). The cellular effects of these different PDGF isoforms are mediated by binding, with different specificities, to three transmembrane receptors isoforms of type tyrosine kinase generated by the association of subunits ? e ? (PDGFR- ??, - ??, - ??). PDGF was initially purified from platelets, being later verified its production by many varieties of cell types. It acts as an important mitogenic factor, especially to cells of mesenchymal origin as fibroblasts and smooth muscle cells, and also exerts a role on cellular migration and survival. Studies with PDGF and its receptors have demonstrated its importance as a paracrine growth factor for normal embryo development and angiogenesis. Although the action of this growth factor has been shown in several cellular responses, its role in ovarian folliculogenesis of mammals is understudied. Folliculogenesis, event initiated at pre-natal life in most species, can be defined as the process of follicular formation, growth and maturation, beggining with the primordial follicle formation and resulting in preovulatory stage. Until the present moment, the different PDGF types and their receptors were detected in ovarian follicles of murines, rodents, swines and humans according to developmental stage. Evidences suggest that this growth factor may acts as a potent regulator of ovarian function, increasing DNA synthesis in granulosa cells and stimulating theca cells growth in swines. In addition, PDGF has shown benefic effects in in vitro maturation of bovine oocytes when associated with follicle stimulating hormone (FSH). Conclusion: Nevertheless, the specific actions of PDGF on ovarian follicles development have not been described due to lack of data available in the literature about this subject. Therefore, this review was performed to clarify the involvement of this growth factor in the regulation of ovarian function in mammals. However, it is necessary to perform additional studies that may provide a greater understanding about the importance of PDGF during folicullogenesis

    Síndrome de Wernicke-Korsakoff associada ao álcool / Wernicke-Korsakoff syndrome associated with alcohol

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    A Síndrome de Wernicke-Korsakoff (SWK) caracteriza-se por uma amnésia anterógrada com um estado de distúrbio mental, marcha atáxica e nistagmo sendo causada por uma deficiência de tiamina, encontrada principalmente em alcoólatras e pessoas desnutridas. O álcool interfere ativamente no processo de absorção gastrintestinal, reduzindo a ativação da tiamina e o também o estoque de tiamina hepática. Como a tiamina é necessária nos mecanismos de condução axonal dos neurônios, a falta da mesma por volta de três semanas é suficiente para gerar danos neurológicos. Na SWK, as lesões são tipicamente simétricas e próximas ao plano mediano. Relacionando as manifestações clínicas com as lesões, o paciente apresenta: amnésia anterógrada e confabulação (corpos mamilares), alteração do estado de consciência (regiões talâmicas mediais), marcha atáxica (cerebelo), oftalmoparesia (nervo VI e VIII) e nistagmo (complexo nuclear vestibular, cerebelo, tegmento pôntico e o fascículo longitudinal medial. O tratamento é feito à base de tiamina endovenosa que se for aplicada precocemente pode reverter algumas manifestações clínicas

    Incidência da síndrome pré-menstrual na prática de esportes: aspectos atuais: Incidence of pre-menstrual syndrome in sports: current aspects

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    A síndrome pré-menstrual (SPM) é uma constelação complexa de alterações de humor, comportamentais e físicas que se limitam à fase pré-menstrual. Esses sintomas se recuperam dentro de alguns dias após o início da menstruação.  Assim, o objetivo desse estudo é demonstrar a incidência da síndrome pré-menstrual na prática de esportes a partir de uma revisão integrativa sobre o tema. Para isso, foi realizado uma revisão integrativa sobre o tema, onde foi considerado textos publicados desde 2010, em inglês e português e que estejam disponíveis para leitura, no PUBMED, LILACs e Scielo. Esta revisão sistemática fornece algum suporte adicional para diretrizes clínicas que recomendam o exercício como um tratamento eficaz para a TPM. As análises secundárias realizadas também fornecem novas evidências de que o exercício pode ser útil no alívio de sintomas psicológicos, físicos e comportamentais específicos associados à TPM, além de auxiliar no gerenciamento do perfil global de sintomas

    Alcoolismo em pacientes submetidos a cirurgia bariátrica: uma revisão sistemática: Alcoholism in patients undergoing bariatric surgery: a systematic review

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    A Cirurgia bariátrica tem sido uma opção de muitas pessoas que visam superar a obesidade e garantir qualidade de vida e saúde. No entanto, casos de complicações clínicas após operação tem ocorrido, sendo comum a incidência de alcoolismo. Este estudo teve como objetivo refletir sobre as causas da incidência de alcoolismo entre pacientes que foram submetidos a cirurgias bariátricas. Para o alcance dessa finalidade, realizou-se uma revisão sistemática de literatura, selecionando-se fontes das bases de dados Scielo Brasil, PubMed e Biblioteca Virtual em Saúde (BVS), publicados em língua portuguesa, nos anos de 2017 a 2022. Realizando-se a análise dos dados concluiu-se que o transtorno do uso de álcool em pessoas submetidas à cirurgia bariátrica tem sido recorrente, especialmente entre homens de baixa renda e que fizeram a cirurgia do tipo bypass gástrico. Observou-se também que o consumo de álcool é maior no pós-operatório e que boa parte dos pacientes que se submeteu a esse tipo de cirurgia ignorava o risco de desenvolver o referido transtorno. Em função disso, boa parte dos estudos que integraram esta revisão reconhece a necessidade do acompanhamento, pela equipe de saúde, dos pacientes logo após a cirurgia bariátrica e a adesão desses ao tratamento devido, visando prevenir o transtorno do uso de álcool

    USO DO ALOPURINOL E ASSOCIAÇÕES COMO TRATAMENTO ALTERNATIVO PARA LEISHMANIOSE VISCERAL CANINA

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    O presente trabalho consiste em apresentar informações sobre experimentações utilizando protocolos alternativos em animais com leishmaniose visceral canina (LVC). A eutanásia dos cães tem sido bastante criticada pelo fato de que não surte efeito de redução das taxas da doença e que o tratamento dos animais seria uma opção para o controle da LVC. A polêmica fez com que o governo federal brasileiro regulamentasse um medicamento veterinário importado para o tratamento dos cães, porém a dificuldade de acesso ao mesmo levou os veterinários às experimentações de protocolos de baixo custo que se mostrassem eficazes no combate à LVC. Alguns animais apresentaram respostas positivas às diferentes drogas com custo bem mais baixo do que o medicamento que foi legalizado pelo governo. Assim, por esse motivo, a pesquisa teve como objetivo, por meio de uma visão crítica, discutir e avaliar esses tratamentos utilizados para controlar a LVC. Os protocolos consistiram na administração do medicamento de uso humano (alopurinol), que mostrou ter função leishmaniostática aliada a outros compostos, como antimicrobianos, antiparasitários e antifúngicos. O presente estudo se dá por meio de uma revisão de literatura narrativa e os artigos selecionados abordaram o uso do alopurinol associado a outras drogas e seus efeitos para o controle da LVC. Os resultados encontrados mostram que esses tratamentos levaram à diminuição dos seguintes achados laboratoriais: sinais clínicos da doença, carga parasitária do animal e infectividade ao mosquito transmissor. Assim, conclui-se que esses protocolos alcançaram as expectativas de eficácia e segurança para combater a leishmaniose visceral canina

    Caracterização estrutural do fator de crescimento de fibroblasto-10 (FGF-10) e seu papel na fisiologia folicular ovariana

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    Background: Interest in folliculogenesis has grown extensively in recent years. Nevertheless, several aspects of follicular activity are still poorly understood. Thus, in vitro culture of ovarian follicles using new substances has been established as a very viable model, enhancing the prospects for a better understanding of follicular activity. Among the family members of the fibroblast growth factor (FGFs), FGF-10 has received recent attention for its ability to regulate the development of ovarian follicles and oocyte maturation. Given the relevance of FGF-10 in the folliculogenesis process, this review aimed to describe the structural features, expression and the main biological effects of FGF-10 on the development of ovarian follicles in mammals.Review: Along this work, it was shown aspects related to structural characterization of FGF-10 and its receptors, as well as FGF-10 expression in different cell types, emphasizing its importance to follicular development. FGF-10 is a paracrine member of the family of FGFs, and is characterized by promoting biological responses via cell surface receptors (FGFRs) of tyrosine kinase-type. of these receptors, FGFR-1, FGFR-2 and FGFR-3 may undergo alternative transcriptional arrangements, enabling the formation of two isoforms (b and c) that have varying degrees of affinity for the various FGFs. Thus, seven FGFR proteins (FGFRs 1b, 1c, 2b, 2c, 3b, 3c and 4) with different binding specificities are generated from the four FGFR genes. The FGFRs transmit intracellular signals after binding with the ligand through the phosphorylation of tyrosine, which activates various transduction patterns in the cytoplasm. The signal transduction of FGF-10 may occur through three main pathways: protein of rat sarcoma (Ras)/MAPK, PLC gamma/Ca(2+) and phosphatidylinositol-3 kinase (PI3K)/protein kinase B (Akt), which are involved in the transmission of biological signals, leading to cellular proliferation and differentiation. FGF-10 mRNA expression was detected in the ovarian stroma, oocyte and theca cells of preantral and antral follicles. on the other hand, the expression of mRNA for FGF-10 receptors was found in, granulosa cells, theca cells, cumulus cells and oocytes. Although FGFs are widely distributed in different tissues and cell types, the importance and function of FGFs in the ovary are still poorly documented. FGF-10 has been shown to be an important mediator of mesenchymal and epithelial cell interactions during follicle development, promoting follicular survival, activation and growth. Besides the action on folliculogenesis, FGF-10 was recently identified as a growth factor able to improve oocyte competence. However, in antral follicles, the presence of FGF-10 is associated with increased follicular atresia, which matches its anti-estrogenic action.Discussion: From this review, we can conclude that FGF-10 is an important regulator of female reproduction. This growth factor acts in follicle survival, oocyte maturation, expansion of cumulus cells and proliferation of granulosa/theca cellsthrough direct and/or indirect actions in the control of folliculogenesis. Furthermore, FGF-10 seemed to have different effects throughout the follicular development. However, it is necessary to perform additional studies that may provide a better understanding about the importance of FGF-10 during folicullogenesis
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