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São Paulo, Brazil

Sfair J.C.,University of Campinas | Rochelle A.L.C.,University of Campinas | Rezende A.A.,Rio Preto Universitary Center | van Melis J.,University of Campinas | And 2 more authors.
Perspectives in Plant Ecology, Evolution and Systematics | Year: 2010

Despite the increasing number of studies on lianas, few of them have focused on liana and host-tree (phorophyte) interactions from a network perspective. Most studies found some network structure in other systems, such as plant facilitation and host-epiphyte. However, a recent study found no structure in a small network of liana-phorophyte interactions. Our aim was to investigate the hypothesis that rich, highly diverse systems yield large interaction networks with some structure. If so, networks of liana-phorophyte interactions in highly diverse systems will have one or more of the following structures: compartmentalized, nested or compound. We sampled three highly diverse vegetation formations: a tropical rainforest, a tropical seasonally dry forest, and a woodland savanna, all in southeastern Brazil. We used simulated annealing to test compartmentalization and found no compartment in any of the three networks analyzed. By means of a modified classical temperature index, we found a nested structure in all three sites sampled. We inferred that these nested structures might result from phorophyte characteristics and sequential colonization by different liana species and might promote increased diversity in tropical tree formations. We propose that, according to the system complexity and the different variables associated with site and liana-phorophyte characteristics, a network may have a structure, which arises in more complex systems. Since we have investigated highly diverse systems with large networks, nestedness could be clearly detected in our study. © 2010 Perspectives in Plant Ecology, Evolution and Systematics. Source


Biancardi M.F.,University of Campinas | Perez A.P.S.,University of Campinas | Goes R.M.,Sao Paulo State University | Santos F.C.A.,Federal University of Goais | And 3 more authors.
Experimental Biology and Medicine | Year: 2012

The development of the prostate depends on a precise androgenic control, so sensible interferences may predispose this gland to develop prostatic diseases during life. These aspects are of interest and preoccupation, since human beings are exposed to a growing number of endocrine-disrupting chemicals with androgenic potential. Therefore, our aim was to evaluate the prostates of adult gerbils exposed to testosterone during intrauterine life. Serological, morphological, morphometric- stereologic, immunohistochemical and three-dimensional reconstruction analyses were used. We found that the testosterone effects were dose-dependent and more harmful to females, leading to the development of masculine characteristics, evidenced by an increased anogenital distance, and absence of vaginal opening and the ectopic development of prostatic tissue. Moreover, premalignant lesions, such as prostatic intraepithelial neoplasia, were observed in addition to inflammatory foci in the prostate. The results showed that the prenatal exposure to testosterone may affect the reproductive system, disrupting developmental processes and increasing susceptibility to the development of prostatic diseases in the Mongolian gerbil. © 2008 Society for Experimental Biology and Medicine. Source


Biancardi M.F.,Institute of Biology | Santos F.C.,Federal University of Goais | Madi-Ravazzi L.,Sao Paulo State University | Goes R.M.,Sao Paulo State University | And 3 more authors.
Anatomical Record | Year: 2010

The female prostate (Skene's paraurethral gland) in the rat is morphologically similar to the ventral lobe of male adults and has been described in other rodent species and humans. Previous studies on prostate morphogenesis suggest that female Wistar rats (Rattus norvegicus) do not develop this gland due to the absence of testosterone during the embryonic and neonatal periods. On the other hand, studies conducted in our laboratory have shown that some females of this species can present an undeveloped but functional prostate. Recent studies on this gland have caused scientific interest because, besides being active in the processes of synthesis and secretion of prostatic material, it is also targeted by both malignant and benign lesions, mainly during senescence. Thus, this work aims to evaluate the structure of female prostate of adult rats (Rattus norvegicus) under normal conditions and under the effect of testosterone treatment and carry out comparative studies on the ventral prostate of young and adult male rats. Morphological and morphometric stereological analyses and immunocytochemical and ultrastructural studies were conducted. The results have shown that the prostate gland of rats exposed to androgen therapy have experienced intense growth, becoming more active in relation to synthesis and secretion. It may be concluded that the prostate in control adult female rats is morphologically very similar to the prostatic ventral lobe of young male rats. Besides, under androgenic action, the female prostate grows considerably and becomes similar to the prostatic ventral lobe in male adults. © 2010 Wiley-Liss, Inc. Source


Santos F.C.A.,Federal University of Goais | Rochel-Maia S.S.,University of Campinas | Fochi R.A.,University of Campinas | Justulin L.A.,Federal University of Triangulo Mineiro | And 5 more authors.
General and Comparative Endocrinology | Year: 2011

The gerbil female prostate undergoes morphological and physiological changes resulting from hormonal fluctuations that occur during the reproductive cycle. These repetitive cycles of glandular growth and regression are followed by an extensive reconstruction and remodeling of prostate stroma throughout the reproductive life of the female gerbil. The objective of this study was to evaluate the effect that the hormonal fluctuations of the reproductive cycle have on the stromal remodeling and the expression and activity of matrix metalloproteinases MMP-2 and -9 in the adult female gerbil prostate. For this, serological, ultrastructural, immunohistochemical and biochemical methods were employed. The results showed that the major stromal alteration coincide with the peak of estradiol, which occurs in estrus, and with the peak of progesterone, occurring during diestrus II. MMP-2 and -9 presented a similar pattern of expression and activity during estrous cycle. The estrus was the phase of greater expression and activity of MMP-2 and -9. On the other hand, in DI and DII, the tissue expression and activity of MMP-2 and -9 was very weak. These results are important since they suggest the involvement of estradiol and progesterone in regulating the expression and activity of MMP-2 and -9 in adult gerbil female prostate. © 2011 Elsevier Inc. Source


Custodio A.M.G.,University of Campinas | Santos F.C.A.,Sao Paulo State University | Santos F.C.A.,Rio Preto Universitary Center | Campos S.G.P.,Sao Paulo State University | And 4 more authors.
International Journal of Experimental Pathology | Year: 2010

The female organs, which are regulated by steroid hormones, are targets of studies especially those related to senescence. However, although the female prostate is an organ influenced by hormones and susceptible to lesions, there is still little information about its histopathology. Thus, given the morphophysiological similarity between the prostate in women and female gerbils, the present study aimed to identify the spontaneous histopathological changes in this rodent to provide contributions to the understanding of lesions that also affect the human female prostate. The structural, ultrastructural, immunohistochemical, morphometric-stereological and serological aspects, as well as the quantification of the incidence, multiplicity and percentage of acini affected by different lesions were analyzed. Benign prostate lesions including hyperplasia, prostatitis, microcalculi and calculi; preneoplastic lesions like dysplasias; premalignant lesions, such as high grade prostatic intraepithelial neoplasia as well as malignant ones, specifically adenocarcinoma, were identified in the adult gland, but they were intensified during senescence, which is possibly due to the imbalance among steroid hormone levels. Although clinical attention focuses on other urogenital organs, the real condition of the histopathological injuries in the human female prostate should be considered. A serious preventive work regarding the female prostate could be applied in the gynaecological context in order to monitor the gland and avoid possible disturbances to women's health and consequently provide better quality of life. © 2009 Blackwell Publishing Ltd. Source

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