Sérgio F. Oliveira
University of São Paulo
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Featured researches published by Sérgio F. Oliveira.
Journal of Cardiovascular Pharmacology | 2002
Maria do Carmo Pinho Franco; Robéria Maria M.P Arruda; Zuleica B. Fortes; Sérgio F. Oliveira; Maria Helena C. Carvalho; Rita C. Tostes; Dorothy Nigro
Epidemiologic studies suggest that intrauterine undernutrition plays an important role in the development of arterial hypertension in adulthood. The aim of the current study was to evaluate whether severe nutritional restriction during pregnancy can aggravate hypertension, vascular reactivity changes, and renal development in spontaneously hypertensive rat (SHR) offspring. To investigate the potential existence of gender differences, both male and female offspring of pregnant SHRs on a restricted diet were studied in adulthood. Female pregnant SHRs were fed either normal or 50% of the normal intake diets, during the whole gestational period. Arterial blood pressure and nephron number were determined. Norepinephrine, acetylcholine, and sodium nitroprusside responses in isolated aortic rings from the offspring (male and female, when they reached adulthood) were also evaluated. In the SHR offspring (male and female) the intrauterine undernutrition further increased the blood pressure levels, increased the response to norepinephrine, and decreased the response to acetylcholine, without altering the response to sodium nitroprusside. In addition, it induced a decrease in the number of nephrons in the kidney from adult offspring. In conclusion, fetal undernutrition aggravates hypertension and the endothelial dysfunction along with an impairment of renal development in both male and female SHRs.
Journal of Anatomy | 2010
Juliane C. T. Sanches; Carolyn J.P. Jones; John D. Aplin; Renato V. Iozzo; Telma M. T. Zorn; Sérgio F. Oliveira
In the pregnant mouse endometrium, collagen fibrillogenesis is characterized by the presence of very thick collagen fibrils which are topographically located exclusively within the decidualized stroma. This dynamic biological process is in part regulated by the small leucine‐rich proteoglycans decorin and biglycan. In the present study we utilized wild‐type (Dcn+/+) and decorin‐deficient (Dcn−/−) time‐pregnant mice to investigate the evolution of non‐decidualized and decidualized collagen matrix in the uterine wall of these animals. Ultrastructural and morphometric analyses revealed that the organization of collagen fibrils in the pregnant endometrium of both non‐decidualized and decidualized stroma showed a great variability of shape and size, regardless of the genotype. However, the decidualized endometrium from Dcn−/− mice contained fibrils with larger diameter and more irregular contours as compared to the wild‐type littermates. In the Dcn−/− animals, the proportion of thin (10–50u2003nm) fibrils was also higher as compared to Dcn+/+ animals. On day 7 of pregnancy, biglycan was similarly localized in the decidualized endometrium in both genotypes. Lumican immunostaining was intense both in decidualized and non‐decidualized stroma from Dcn−/− animals. The present results support previous findings suggesting that decorin participates in uterine collagen fibrillogenesis. In addition, we suggest that the absence of decorin disturbs the process of lateral assembly of thin fibrils, resulting in very thick collagen fibrils with irregular profiles. Our data further suggest that decorin, biglycan and lumican might play an interactive role in collagen fibrillogenesis in the mouse endometrium, a process modulated according to the stage of pregnancy.
Histochemistry and Cell Biology | 2000
Sérgio F. Oliveira; Cláudio S. Greca; Paulo A. Abrahamsohn; M.G. Reis; Telma M. T. Zorn
Decidualization of the mouse endometrium consists of a redifferentiation of the endometrial stromal fibroblasts. During decidualization these fibroblasts undergo growth, change of shape, multinucleation, and establishment of intercellular junctions. One feature of rodent decidual cells is the accumulation of intermediate filaments. In spite of the fact that fibroblasts normally have vimentin intermediate filaments, they acquire a large amount of desmin intermediate filaments while they undergo decidualization. The light and electron microscope immunocytochemical results of the present work show that during the initial stages of decidual transformation the desmin intermediate filaments accumulate around the nuclei, often forming caps around the nuclear envelope. As the decidual cells grow, the filaments form bundles and nets that radiate from the nuclei toward the cell surface. During the final stages of differentiation, on dayxa08 of pregnancy, staining of differentiated decidual cells decreases and most filaments accumulate under the cell surface. A role for intermediate filaments is suggested for decidualization of mouse endometrial cells.
Journal of Pharmacological and Toxicological Methods | 1993
Naira Cusma-Pelógia; Sérgio F. Oliveira; Dorothy Nigro; Maria Helena C. Carvalho; Regina Scivoletto; Zuleica B. Fortes
In order to choose the best procedure to inactive the endothelium from vascular beds perfused in vitro, we compared four methods: perfusion with sodium deoxycholate 0.3% for 30 sec; 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate 0.3% (CHAPS) for 2.5 min; collagenase 0.2% for 15 min, and distilled water for 10 min, using the mesenteric arterial bed (MAB) of the rat. The effectiveness of the treatments used to inactivate the endothelium was assessed functionally by using acetylcholine and sodium nitroprusside and histologically using light microscopy. Phenylephrine was used to test the contractile properties of the preparations after each treatment. After collagenase, distilled water, and CHAPS treatment, a potentiated response to phenylephrine was observed, whereas sodium deoxycholate treatment did not modify phenylephrine-induced responses. Acetylcholine-induced responses were reduced by collagenase (60% reduction), CHAPS (30% reduction), and distilled water (52% reduction) treatment, and sodium deoxycholate completely abolished acetylcholine-induced responses. Except after collagenase treatment, smooth muscle relaxant responses were not altered. Medial smooth muscle cells displayed an unchanged morphology, appearing similar to those in control mesenteric arterial beds, except for collagenase and distilled water. Despite the fact that sodium deoxycholate treatment completely abolished acetylcholine-induced response, endothelial cells were still found. No treatment totally removed endothelial cells. In conclusion, we suggest that sodium deoxycholate treatment is the best procedure to inactivate endothelial cells from vascular beds perfused in vitro since it completely abolished endothelium-dependent relaxation and did not interfere with smooth muscle vasodilating and contracting properties.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology | 1997
Nilima K. Badwaik; John J. Rasweiler; Sérgio F. Oliveira
As part of an effort to develop the short‐tailed fruit bat (Carollia perspicillata) as a new animal model for the study of interstitial implantation and trophoblast‐uterine interactions, early embryogenesis was examined histologically and ultrastructurally in captive‐bred females at different intervals after the first appearance of spermatozoa in daily vaginal smears (day 1 postcoitum [p.c.]).
Cells Tissues Organs | 2001
Fernanda L. Monice; Célia G.T. Andrade; Paulo A. Abrahamsohn; Mauricio Soto-Suazo; Sérgio F. Oliveira; Telma M. T. Zorn
Decidual cells are endometrial fibroblasts that redifferentiate during pregnancy in several species of mammals. In this work, we describe a subpopulation of resident decidual cells in the mouse endometrium that are joined by intercellular junctions and have cytoplasmic granules. Decidualization was induced in pseudopregnant mice on the 4th day of pseudopregnancy by injection of 30 µl of arachis oil into the uterine lumen. The uteri were collected on day 8 of pseudopregnancy (at 4 p.m., 8 p.m. and 11 p.m.) and on day 9 (at 8 a.m.). The tissues were fixed for light and electron microscopy. During day 8 of pseudopregnancy, granulated cells were present at the antimesometrial pole of the endometrium; they were concentrated at the periphery of the antimesometrial decidua and disappeared on day 9 of pseudopregnancy. The cytoplasm of the granulated decidual cells had acidophilic granules that stained also with periodic acid-Schiff (PAS). These granules stained with anti-rat prolactin antibody in both light and electron microscope immunocytochemical preparations. Vacuoles of various sizes were always present in the granulated cells. A PAS-positive and prolactin-stained material was often deposited at the periphery of the vacuoles. Our results indicate that the granulated decidual cells are the source of decidual prolactin which accumulates in cytoplasmic granules. These granulated cells therefore form a transient gland in the mouse antimesometrial endometrium (granulated decidual gland).
Anatomy and Embryology | 2000
Sérgio F. Oliveira; John J. Rasweiler; Nilima K. Badwaik
The final stages of embryonic development in the oviduct, transport of the embryo to the uterus, and the initial stages of implantation have been examined in captive-bred Carollia perspicillata at the light and electron microscopic levels. Development progressed to the expanded, zona pellucida-free, blastocyst stage in the oviduct. The abundance of microvilli on the exterior of the trophoblast varied with the degree of blastocyst expansion and cell shape, and may function in part as a membrane reservoir. Cells of the blastocyst also typically contained many lipid droplets and prominent areas of cytoplasm occupied by finely granular material (probably glycogen) instead of organelles. In most females, closure of the uterine lumen occurred prior to, or around the time of, transport of the blastocyst to the usual implantation site and appeared to play a role in preventing transport of the blastocyst too far distally in the uterus. This was associated with increased endometrial edema, particularly in the fundic region of the simplex uterus, and the extravasation of many erythrocytes into the endometrial stroma. Both of these changes began while the blastocyst was still being held in the oviduct and became pronounced during implantation. Engulfment of these erythrocytes by processes of the endometrial stromal cells and their phagocytosis by macrophages was also observed. Implantation was usually initiated within narrow tubular segments, lined by endometrium, that were located between the end of each oviduct and the main cavity of the uterus, or from immediately adjacent areas of the main cavity. During the early stages of implantation, the blastocyst was clasped by the endometrium at the implantation site, and this was associated with extensive interdigitation of the microvilli of the trophoblast and adjacent uterine epithelial cells. Initial adhesion of the trophoblast, which was still cellular rather than syncytial, occurred over the apical intercellular junctions of the uterine epithelial cells.
Brazilian Journal of Medical and Biological Research | 1998
Sérgio F. Oliveira; Paulo A. Abrahamsohn; Telma M. T. Zorn
The rodent endometrium undergoes remarkable modifications during pregnancy, resulting from a redifferentiation of its fibroblasts. During this modification (decidualization), the fibroblasts transform into large, polyhedral cells that establish intercellular junctions. Decidualization proceeds from the subepithelial stroma towards the deep stroma situated next to the myometrium and creates regions composed of cells in different stages of differentiation. We studied by autoradiography whether cells of these different regions have different levels of macromolecular synthesis. Radioactive amino acids or radioactive sulfate were administered to mice during estrus or on different days of pregnancy. The animals were killed 30 min after injection of the precursors and the uteri were processed for light microscope autoradiography. Silver grains were counted over cells of different regions of the endometrium and are reported as the number of silver grains per area. Higher levels of incorporation of amino acids were found in pregnant animals as compared to animals in estrus. In pregnant animals, the region of decidual cells or the region of fibroblasts transforming into decidual cells showed the highest levels of synthesis. Radioactive sulfate incorporation, on the other hand, was generally higher in nonpregnant animals. Animals without decidual cell transformation (nonpregnant and 4th day of pregnancy) showed a differential incorporation by subepithelial and deep stroma fibroblasts. This study shows that regional differences in synthetic activity exist in cells that are in different stages of transformation into decidual cells as well as in different regions of the endometrium of nonpregnant mice.
Placenta | 2016
Adriana Fraga Costa; Sara Zago Gomes; Aline R. Lorenzon-Ojea; Mariane Martucci; Miriam Rubio Faria; Décio dos Santos Pinto; Sérgio F. Oliveira; Francesca Ietta; Luana Paulesu; Estela Bevilacqua
The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has an anti-apoptotic effect through several downstream targets, which includes activation of the transformed mouse 3T3 cell double-minute 2 (Mdm2) protein, its translocation to the nucleus and degradation of the tumor suppressor p53. We show that Mif, the Macrophage Migration Inhibitory Factor, an important cytokine at the maternal fetal interface in several species, triggers phosphorylation of Mdm2 protein in a PI3K/Akt-dependent manner, thereby preventing apoptosis in cultured mouse decidual cells. Inhibition of Akt and PI3K suppresses the pathway. Mif treatment also changes the nuclear translocation of p53 and interferes with the apoptotic fate of these cells when challenged with reactive oxygen species. In conclusion, an important mechanism has been found underlying decidual cell survival through Akt signaling pathway activated by Mif, suggesting a role for this cytokine in decidual homeostasis and in the integrity of the maternal-fetal barrier that is essential for successful gestation.
Revista Brasileira De Cirurgia Cardiovascular | 1990
José Carlos R Iglézias; Luís Alberto Dallan; Sérgio F. Oliveira; Ramires Ja; Sérgio Almeida de Oliveira; Geraldo Verginelli; Fúlvio Pileggi; Adib D Jatene
Five-hundred and three patients, with age equal or above 80 years, were surgically treated at the Heart Institute from January 78 to July 90. Aiming to characterize this octogenarian population submitted to myocardial revascularization, data were retrospectively pursued. This study analyzed clinical,radiological, hemodynamic, operative and postoperative factors; there was no statistical analysis of the material. Hospital mortality was 2/15 (13.33%) and in a mean follow-up of 24.7 months (5-50) five patients evoluted to death due to hemorrhagic vascular cerebral accident, urinary tract infection, mesenteric thrombosis, pulmonary infection and diabetis dysfunction, secondary to urinary tract infection. All of the survivals improved as to the sintomatology related to angina and cardiac insufficiency. Observations based on the data collected reveal that 1) there was no operative death; 2) hospital mortality was related to infectious processes; 3) in late follow-up the great majority of patients referred improvement as to the sintomatology and therefore in the quality of life, and 4) isolatedly, age did not represent a risk factor for surgical treatment.