144 research outputs found

    Síndrome do ovário policístico: caracterização termporal do processo de indução e reversão em um modelo experimental

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    Numerosos modelos experimentais têm sido desenvolvimos para o estudo da síndrome do ovário policístico em ratos. No presente estudo, a síndrome foi inducida por exposição à luz constante. O processo foi avaliado durante sua indução e inclusive durante sua reversão. O ciclo estral foi analisado através de citologia vaginal; parámetros reprodutivos foram avaliados por acasalamento, bem como a morfologia ovariana. Todos animais desenvolveram a síndrome depois de 13 semanas de luz permanente. As características histológicas dos ovários, na semana 15, foram similares àquelas observadas na síndrome do ovário policístico em humanos e outras espécies. Após a regressão da síndrome, não houve diferenta em nenhum dos parámetros reprodutivos avaliados, quando comparados com o grupo controle.Numerous experimental models have been developed for the study of the polycystic ovarian syndrome in the rat. In the present study, the syndrome was induced by exposure to constant light. The process was evaluated during its induction and also during its reversion. The estral cycle was analyzed through the vaginal cytology; reproductive parameters were evaluated by mating, as well as the ovarian morphology. All the animals developed the syndrome after 13 weeks of permanent light. The histologic characteristics of the ovaries, at week 15, were similar to those observed in the polycystic ovarian syndrome in human and other species. After regression of the syndrome, there was not difference in any of the evaluated reproductive parameters, when compared with the control group

    Swine as an experimental model in dentistry: a proposal of surgical approach

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    Swine is widely used as an experimental model in several areas of medicine based on its anatomical and physiological similarities to humans. In this report, we describe an external surgical approach on the mandible of the swine as a suitable experimental model in dentistry. Several biomaterials were implanted by using this technique in order to evaluate the degree of bone regeneration as well as the suitable sites to accomplish perforation

    Morphology and histology of the uropygial gland in Antarctic birds: relationship with their contact with the aquatic environment?

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    Fil: Chiale, María Cecilia. División Zoología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Fernández, Patricia E.. Cátedra de Patología Genera. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Gimeno, Eduardo J.. Cátedra de Patología General. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Barbeito, Claudio G.. Cátedra de Histología y Embriología. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Montalti, Diego. División Zoología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin

    El clima motivacional a les classes d’Educació Física: una aproximació pràctica des de la Teoria de Fites d’Assoliment

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    Al treball següent es fa una anàlisi dels processos motivacionals que es desenvolupen a les classes d’Educació Física. Prenent com a fonament la Teoria de les Fites d’Assoliment (Nicholls, 1989; Ames, 1992), s’expliquen cada un dels diferents constructes que formen la teoria esmentada (Orientacions, Climes i Implicacions Motivacionals) i la relació entre ells. També s’hi exposen diverses investigacions que han demostrat aquestes relacions, i de quina manera el desenvolupament d’un clima que implica vers la tasca pot millorar i fer més adaptatius els patrons conductuals dels alumnes. Finalment, es fa una proposta metodològica per desenvolupar un clima que impliqui vers la tasca per part del professorat d’Educació Física, amb els beneficis que això reporta

    La implicación motivacional de jugadores jóvenes de fútbol y su relación con el estado de Flow y la satisfacción en competición

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    El propósito de este estudio ha sido intentar determinar las variables predictoras del estado de implicación motivacional de jóvenes jugadores de fútbol y la relación que el estado de implicación guarda con el Estado de Flow y la atisfacción con el rendimiento obtenido en competición. Para ello, 117 futbolistas rellenaron un conjunto de cuestionarios para determinar: a) La orientación motivacional de los jugadores, b) la percepción de los criterios de éxito en el utilizados por el entrenador en el deporte y en una competición, c) el estado de implicación motivacional obtenido por los jugadores en competición, d) el Estado Flow obtenido en la competición, y e) la satisfacción con el rendimiento durante lacompetición. Los resultados se obtuvieron a través del cálculo de Modelos de Ecuaciones Estructurales, mostrando que únicamente las variables situacionales (percepción de criterios de éxito implicantes al ego y a la tarea) predicen de formasignificativa los estados de implicación al ego y a la tarea en competición, respectivamente. El estado de Flow en competición fue predicho tanto por el estado de implicación al ego como por el estado de implicación a la tarea. Por ltimo, la satisfacción en competición es predicha positivamente por el Estado de Flow en competición y la implicación a la tarea y negativamente por la implicación al ego.This study attemptd to determine the predictive variables related to goal involvement in young soccer players and the relationship between goal involvement and flow state and competition satisfaction. 117 soccer players completed a set of questionnaires to determine: a) the athletes' goal orientation, b) perception of sport and competition coaches' criteria for success, c) the players' competition goal involvement, d) competition flow state and e) the players' competition satisfaction. Results were obtained via Structural Equation Modelling and showed that only situational variables (perception of ego and task involving coach competition success criteria) were predictors of competition ego and task involvement respectively. Competition flow state was positively predicted by task and ego competition goal involvement. Finally, the results show that satisfaction was positively predicted by competition flow state and task-involvement, and negatively predicted by ego-involvement

    Immunohistochemical Expression of Growth Factors in the Follicular Wall of Normal and Cystic Ovaries of Sows

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    Contents: The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF-I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF-I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF-II was very similar to pattern noted in IGF-I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF-II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors.Fil: Sant'Ana, F. J. F.. Universidade do Brasília; BrasilFil: Reis Junior, J. L.. Universidade do Brasília; BrasilFil: Blume, G. R.. Universidade do Brasília; BrasilFil: Gimeno, Eduardo Juan. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rey, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Ortega, Hugo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentin

    An imbalance between apoptosis and proliferation contributes to follicular persistence in polycystic ovaries in rats

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    <p>Abstract</p> <p>Background</p> <p>Cystic ovarian disease is an important cause of infertility that affects bovine, ovine, caprine and porcine species and even human beings. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, our objective was to evaluate apoptosis and proliferation in ovarian cystic follicles in rats in order to investigate the cause of cystic follicle formation and persistence.</p> <p>Methods</p> <p>We compared the number of in situ apoptotic cells by TUNEL assay, expression of active caspase-3 and members of Bcl-2 family by immunohistochemistry; and cell proliferation by the expression of the proliferation markers: PCNA and Ki-67.</p> <p>Results</p> <p>The proliferation index was low in granulosa of tertiary and cystic follicles of light exposed rats when compared with tertiary follicles of control animals, while in theca interna only cystic follicles presented low proliferation index when compared with tertiary follicles (p < 0.05). The granulosa of cysts exhibited a similar cell DNA fragmentation to early atretic follicles. In the granulosa and theca interna, active caspase-3 shown similar immunostaining levels in tertiary and cystic follicles (p < 0.05). The granulosa cells presented high expression of Bcl-2, Bcl-xL and Bcl-w in the tertiary and cystic follicles with diminishing intensity in the atretic follicles, except with Bcl-w where the intensity was maintained in the atretic follicles (p < 0.05). The expression of Bax was weak in the healthy and cystic follicles. In the theca interna, Bcl-2 expression was the same as the pattern found in the granulosa; no differences were found between tertiary and cystic follicles from both groups for Bcl-xL and Bcl-w. The expression of Bax in this layer was higher in the tertiary follicles of the treated animals (p < 0.05) while the values for cystic follicles were similar to those in the tertiary follicles of controls. The theca externa showed low expression of the pro and anti-apoptotic proteins.</p> <p>Conclusion</p> <p>These results show that the combination of weak proliferation indices and low apoptosis observed in follicular cysts, could explain the cause of the slow growth of cystic follicles and the maintenance of a static condition without degeneration, which leads to their persistence. These alterations may be due to structural and functional modifications that take place in these cells and could be related to hormonal changes in animals with this condition.</p

    Estrogen receptors α and β and progesterone receptors in normal bovine ovarian follicles and cystic ovarian disease

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    The purpose of this study was to determine by immunohistochemistry the expression of estrogen and progesterone receptors in ovarian follicular structures from cows with cystic ovarian disease (COD) and to compare these with normal ovarian structures. Secondary, tertiary, atretic, and cystic follicles were evaluated. The follicular cysts of animals with COD presented a significantly higher expression of estrogen receptor a in all follicular layers than secondary, tertiary, and atretic follicles in both groups (P < .05). The intensity of estrogen receptor β in the granulosa cell layer was stronger in tertiary than in secondary and atretic follicles in normal animals (P < .05) and in growing and cystic follicles in animals with COD (P < .05). Theca cells were scarcely stained in the 2 groups. Growing follicles and cysts from COD animals were less stained than tertiary follicles from normal animals (P < .05). Differences did not exist between the 2 groups with regard to the progesterone receptor. Ovaries of animals with COD exhibited altered estrogen receptors expression compared with that in normal animals.Facultad de Ciencias Veterinaria

    Estrogen receptors α and β and progesterone receptors in normal bovine ovarian follicles and cystic ovarian disease

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    The purpose of this study was to determine by immunohistochemistry the expression of estrogen and progesterone receptors in ovarian follicular structures from cows with cystic ovarian disease (COD) and to compare these with normal ovarian structures. Secondary, tertiary, atretic, and cystic follicles were evaluated. The follicular cysts of animals with COD presented a significantly higher expression of estrogen receptor a in all follicular layers than secondary, tertiary, and atretic follicles in both groups (P < .05). The intensity of estrogen receptor β in the granulosa cell layer was stronger in tertiary than in secondary and atretic follicles in normal animals (P < .05) and in growing and cystic follicles in animals with COD (P < .05). Theca cells were scarcely stained in the 2 groups. Growing follicles and cysts from COD animals were less stained than tertiary follicles from normal animals (P < .05). Differences did not exist between the 2 groups with regard to the progesterone receptor. Ovaries of animals with COD exhibited altered estrogen receptors expression compared with that in normal animals.Facultad de Ciencias Veterinaria

    Calbindin D28k Expression and the Absence of Apoptosis in the Cerebellum of Solatium bonariense L-lntoxicated Bovines

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    Solanum bonariense intoxication is characterized by cerebellar neuronal vacuolation, degeneration, and necrosis. Cerebellar Purkinje cells seem especially susceptible, but more research is needed to determine the pathogenesis of neuronal necrosis and the mechanism of Purkinje cell susceptibility. Calbindin D28k (CbD28k) is highly expressed in Purkinje cells and has been used as a marker for normal and degenerative Purkinje cells. The goal of this study was to describe S bonariense-induced disease by ascertaining Purkinje cell-specific degenerative changes using CbD28k expression and to correlate this with apoptosis in Purkinje cells, as determined using TUNEL (transferase-mediated dUTP-biotin nick end-labeling) and ultrastructural changes. In all cases, an increase in both dose and duration of S bonariense intoxication resulted in a decrease in the number of Purkinje cells. CbD28k immunohistochemistry was an excellent marker for Purkinje cells because immunoreactivity did not change in normal or degenerative tissues. This finding suggests that excessive calcium excitatory stimulation does not induce rapid neuronal degeneration and death. As found in previous studies, TUNEL tests and electron microscopy suggest that Purkinje cell degeneration and death are not occurring via an apoptotic process. These findings suggest that S bonariense poisoning induces progressive Purkinje cell death that is not mediated by excitotoxicity or apoptotic activation.Facultad de Ciencias Veterinaria
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