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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

O papel de ICAM-1 na barreira trofoblastica e na modulação da resposta inflamatoria em placentites / The role of ICAM-1 in trophoblastic barrier and in modulation of inflammatory response in placentitis

Juliano, Priscila Bianchi 19 June 2006 (has links)
Orientador: Albina Messias de Almeida Milani Altemani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-06T19:27:59Z (GMT). No. of bitstreams: 1 Juliano_PriscilaBianchi_M.pdf: 2749600 bytes, checksum: a6323ddb35a6ed804b6e080a03a83c4a (MD5) Previous issue date: 2006 / Resumo: A participação da barreira trofoblástica na patogènese da vilosite placentária tem sido abordada somente em raros estudos realizados em cultura de tecidos, os quais demonstram que a expressão de ICAM-1 (intercellular adhesion molecule I) por células do trofoblasto viloso poderia permitir o influxo de células maternas para dentro da vilosidade. Para investigar a expressão de ICAM-1 pelo trofoblasto viloso, sua relação com ruptura da barreira trofoblástica e influxo de células imunes para dentro da vilosidade, foram analisadas 18 placentas com placentites (5 causada por T. gondii, 3 por T. cruzi, 2 por P. brasiliensis e 8 de etiologia desconhecida - VED) e 8 sem inflamação. Todas foram analisadas através da técnica de imunoistoquímka, em secções de parafina, utilizando-se anticorpos monoclonais anti-CD45RO, anti-CD20, MAC 387, HAM 56, anti-CD15, anti-hNK e anti-ICAM-1. Nas vilosites, o infiltrado intraviloso era composto principalmente por macrófagos HAM 56+ e linfócitos T UCHL-1+, enquanto que no espaço interviloso as células eram predominantemente monócitos MAC 387+. Na intervilosite por P. brasiliensis, não havia célula inflamatória dentro da vilosidade, enquanto que o infiltrado do espaço interviloso era composto principalmente por monócitos MAC 387+ e neutrófilos CDI5+. Todos os casos com placentite, exceto um, mostraram aumento da expressão de ICAM-1 nas vilosidades inflamadas, a qual estava localizada, quase que exclusivamente, próxima às áreas de ruptura trofoblástica. Nestas, foram observados leucócitos aderidos, apenas nos casos com vilosite. Quando a reação inflamatória ocorria somente no espaço interviloso (infecção por P. brasiliensis) apesar da ruptura trofoblástica e aumento da expressão de ICAM-I, não se observou influxo de leucócitos em direção ao estroma viloso. Nenhuma das placentas sem inflamação mostrou expressão de ICAM-1. Concluindo, o aumento da expressão de ICAM-1 pelo trofoblasto viloso ocorre durante placentites com acúmulo de leucócitos tanto no estroma viloso como no espaço interviloso e, provavelmente, desempenha um importante papel na ruptura da barreira trofoblástica. O influxo de células imunes para o vilo placentário, aparentemente, é mediado por ICAM-1, mas a localização do antígeno no interior da vilosidade é certamente um fator crucial para que isso ocorra. / Abstract: Although an in vitro study has hypothesized that expression of ICAM-1 by villous trophoblasts could be important for the influx of maternal immune cells in villitis, it remains to be shown whether the same phenomenon occurs in human villitis. To investigate the expression of ICAM-1 by villous trophoblasts, its relationship with rupture of the trophoblastic barrier and influx of immune cells into the villi, we analyzed 18 paraffin-embedded placentas with placentitis (5 by T. gondii, 3 by I cruzi, 2 by P. brasiliensis and 8 of unknown aetiology - VTJE) and 8 control placentas by immunohistochemistry using the monoclonal antibodies anti-CD45RO, anti-CD20, MAC 387, HAM 56, anti-CD15, anti-HNK and ami-ICAM-1. In all villitis cases, the inflammatory infiltrate within the villous stroma was composed mainly of HAM 56+ macrophages and UCHL-1 T lymphocytes, but in the intervillous space, the cells were mainly MAC 387+ monocytes. Otherwise, intervillosites caused by P. brasiliensis showed mainly MAC 387+ monocytes, CD15+ granulocytes and none inflammatory cell within the villi. All cases but one of placentitis showed trophoblast overexpression of ICAM-1 in the inflamed villi, located almost exclusively next to the areas of trophoblastic rupture. The villitis cases (caused by T. cruzi, T. gondii and VUE) presented leukocyte adherence in the areas of trophoblastic rupture. When the inflammatory reaction was situated in the intervillous space (placentitis by P. brasiliensis), in spite of the trophoblastic rupture and ICAM-1 overexpression there was no leukocyte influx into villi. None of the control placentas showed ICAM-1 expression. We concluded that overexpression of ICAM-1 by villous trophoblasts occurs during placentitis characterized by accumulation of leukocytes in the villous or intervillous space and probably plays an important role in the rupture of the trophoblastic barrier. The influx of immune cells into the villi appears to be mediated by ICAM-1 but the location of the antigen within villous stroma is certainly a crucial factor for its occurrence. / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas
132

Associação entre crescimento neoplasico e gravidez : estudo do perfil hormonal e alterações placentarias em ratas prenhes potadoras do carcinossarcoma de walker 256 / Neoplasic growth and pregnancy : hormonal profile and placental alterations in pregnant tumor-bearing rats

Drezza, Angela Luzia 15 August 2008 (has links)
Orientador: Maria Cristina Cintra Gomes Marcondes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T23:17:54Z (GMT). No. of bitstreams: 1 Drezza_AngelaLuzia_M.pdf: 45412631 bytes, checksum: ce1384b3632e83597242baa2d9c4670b (MD5) Previous issue date: 2008 / Resumo: A gravidez gera modificações no organismo materno para a implantação do blastocisto, que são provocadas por hormônios como estradiol e progesterona. O tempo e curso de gravidez dependem da unidade materno / fetal, a placenta, que é o órgão responsável pela trocas entre mãe e feto, além de secretar vários hormônios, dentre eles prolactina, estrógenos e progesterona. Quando a gravidez encontra-se associada ao desenvolvimento tumoral, situação de intensa multiplicação celular, podem ocorrer disfunções no desenvolvimento embrionário. Os hormônios sexuais e a prolactina têm suas concentrações alteradas durante a gravidez, para que a mesma transcorra corretamente e, além disso, esses hormônios podem interagir com células do sistema imune. A ação do desenvolvimento tumoral, por sua vez, também é responsável pela elevação, ainda maior, na quantidade de citocinas presentes no organismo. Dessa forma, no presente trabalho, avaliou-se a influência do câncer na regulação dos hormônios necessários à gravidez, bem como no desenvolvimento placentário, uma vez que citocinas presentes no líquido ascítico de animais portadores do carcinossarcoma de Walker 256 afetariam o curso normal da prenhez em ratas. Este trabalho foi realizado através da análise de 3 grupos experimentais (ratas prenhes controle, portadoras de tumor ou inoculadas com liquido ascítico), em relação a aspectos de morfometria placentária, concentrações hormonais (estrógeno, progesterona e prolactina), imunohistoquímica e expressão protéica para os receptores placentários de estrógeno e progesterona, além dos processos de síntese e degradação protéica e biossíntese dos hormônios placentários. Através da análise dos animais inoculados diariamente com líquido ascítico, pudemos comprovar que os fatores presentes no liquido ascitico seriam, então, os maiores responsáveis pela alteração anormal de alguns hormônios durante a gravidez. Neste grupo, verificamos desbalanço hormonal semelhante ao observado no grupo Tumor e, além disso, quando comparado ao grupo Controle, apresentava fetos com peso reduzido, alterações morfológícas, de síntese e alterações na expressão de receptores de estrógeno e progesterona. Como os animais inoculados diariamente com líquido ascítico não eram hospedeiros tumorais e, portanto, não sofriam competição nutricional entre feto e as células tumorais, pudemos observar a ação de efeitos diretos ou indiretos dos fatores produzidos pelo tecido hospedeiro e/ou células tumorais, causando redução do número de células trofoblásticas gigantes e das camadas decidual e labirinto-trofoblastica, além de menor expressão protéica dos receptores de estrógeno e progesterona placentário, como redução do peso fetal. Portanto, concluímos que moléculas efetoras provenientes do sistema imunológico hospedeiro ou produzidas pelas células tumorais são capazes de alterar o curso normal da gravidez, trazendo prejuízos ao desenvolvimento placentário e, por conseguinte, fetal. / Abstract: Pregnancy causes several modifications in the maternal organism for the blastocistic implantation that are made by hormonal action, as oestradiol and progesterone. The pregnancy progress depends on the placenta, maternal / foetal unit, which exchanges nutrients, gas and substances between mother and foetus, and can produce a variety of hormones, like prolactin, oestrogen and progesterone. The association between pregnancy and tumoral growth, two situations that involve intense cell multiplication, can be extremely harmful for the foetus development. Sex hormones and prolactin have their concentrations modified during normal gestational progress and can also interact and modulate many physiological functions, as well as immune cells. In turn, tumour growth can raise body cytokines that may influence the hormones necessary to pregnancy and placenta development. In this work we analyzed 3 experimental groups (Control - pregnant rats without tumour, Tumour - pregnant tumour-bearing rats and Ascitic - pregnant rats inoculated with ascitic fluid daily) evaluating the placental morphometry, serum hormonal concentration (oestrogen, progesterone and prolactin), immunohistochemistry, protein expression of the placental oestrogen and progesterone receptors, and also measurements of ín vítro assays of protein synthesis and degradation and placenta's hormonal biosynthesis. Tumour group animais presented, when compared to the Control group, low foetus weight, molecular and morphological placenta alterations and abnormal pregnancy hormone variation (decrease in progesterone levels and increase in prolactin and oestrogen content). Animais of the ascitic fluid group also showed similar abnormal variation of these hormones in the pregnancy as observed in thé Tumour group, indicating that some factors contained in the ascitic fluid could be the greatest responsible for these alterations. Moreover, when compared to the Control group, the ascitic fluid group also presented low foetus weight and molecular and morphological placenta alterations. Since the ascitic fluid group was not tumour host and, therefore, have no nutritional competition between foetus and tumoral cells, the results allowed to observe the direct and/or indirect effects of the factors produced by the host tissue or tumoral cells. These effects included reduction of trophoblastic giants cells and decidual and trophoblastic layers, less placental and foetal oestrogen and progesterone receptor protein expression and reduced foetal weight. We concluded that humoral effectors from hosts immune system or produced by the tumour cells are able to cause pathological conditions and, during pregnancy, can also cause damages to the placental and foetal development. / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
133

Alterações vasculares tromboticas e não tromboticas dos vasos fetais placentarios : estudo morfologico qualitativo e quantitativo em placentas de natimortos

Altemani, Albina Messias de Almeida Milani, 1953- 26 November 1984 (has links)
Orientador : Jose Lopes de Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-07-14T03:04:04Z (GMT). No. of bitstreams: 1 Altemani_AlbinaMessiasdeAlmeidaMilani_D.pdf: 9166673 bytes, checksum: 7be1fff9edd8bb7c4a49d79988294e36 (MD5) Previous issue date: 1984 / Resumo: No capítulo de Introdução foram abordadas,primeiramente e de maneira suscinta, a anatomia e a histologia dos vasos fetais placentários e posteriormente foi feita uma revisão sobre as alterações microscópicas descritas nos vasos fetais placentários e sobre a patogênese e a freqüência destas alterações em placentas de nativivos e natimortos. Foram ressaltadas as discordâncias entre os autores sobre a interpretação das alterações vasculares em placentas de natimortos, a dificuldade de comparar e compreender os achados dos autores pela freqüente falta de distinção microscópica entre as alterações e a falta de descrição pormenorizada das alterações vasculares. Foi também salientado a inexistência de trabalhos quantitativos que comparem as freqüências de alterações vasculares entre placentas de natimortos e placentas de mães e recém nascidos normais. (continua...) / Abstract: The vascular alterations in placentas of stillborn infants have been a matter of controversy. No detailed morphological descriptions thereof, or of their evolution were found in the literature, nor are there quantitative studies comparing the frequency of vascular alterations between placentas of stillborn infants and normal infants and mothers. The purposes o f this thesis are: a) to describe the microscopical abnormalities of the fetal vessels in placentas of stillborn infants, and in placentas o f normal mothers and infants, b) to evaluate the frequency of the different types of placental vascular alterations in normal placentas and in stillbirths with 1 day,2-7 days and over 7 days of intrauterine retention. c) to examine possible relationships of placental vascular alterations to the primary causes of fetal death and to time of intrauterine retention. Fifty placentas of stillborn infants and another fifty from normal infants and mothers were fixed in 20% formalin as quickly as possible after birth. The placentas were sliced and two blocks taken from normal-looking areas. Paraffin sections were stained with hematoxylin and eosin and Masson's trichrome (continue) / Doutorado / Doutor em Ciências Médicas
134

NUMB and Syncytiotrophoblast Development and Function: Investigation Using BeWo Choriocarcinoma Cells

Carey, Julie January 2012 (has links)
The role of NUMB, a protein important for cellular differentiation and endocytosis in non-placental cells, was investigated in syncytiotrophoblast development and function in the human placenta. The BeWo choriocarcinoma cell line was used as a model for villous cytotrophoblast cells and syncytiotrophoblast to investigate NUMB’s involvement in differentiation and epidermal growth factor receptor (EGFR) endocytosis. NUMB isoforms 1 and 3 were found to be the predominant isoforms and were upregulated following forskolin-induced differentiation. Overexpression of NUMB isoforms 1 and 3 did not mediate differentiation or EGFR signaling. Immunofluorescence analysis revealed that NUMB colocalized with EGFR at perinuclear late endosomes and lysosomes following EGF stimulation. We have demonstrated for the first time that NUMB isoforms 1 and 3 are expressed in BeWo cells, are upregulated in forskolin-differentiated BeWo cells and are involved in ligand-dependent EGFR endocytosis in BeWo cells.
135

Distribuição do volume sanguineo entre a placenta e o recem-nascido : estudo de alguns aspectos de quatro metodos que a modificam

Pinotti, José Aristodemo, 1934-2009 18 July 2018 (has links)
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-07-18T03:37:36Z (GMT). No. of bitstreams: 1 Pinotti_JoseAristodemo_D.pdf: 940592 bytes, checksum: 52b724e9adced7085d4daf6e2d6cf515 (MD5) Previous issue date: 1968 / Resumo: Não apresentado / Abstract: Not informed / Doutorado / Doutor em Medicina
136

Vliv stimulace placentárních buněk in vitro a ex vivo na expresi vybraných ABC a OATP transportérů / The effect of in vitro and ex vivo placental cells stimulation on expression of selected ABC and OATP transporters

Dudičová, Simona January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Simona Dudičová Supervisor: Assoc. Prof. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: The effect of in vitro and ex vivo placental cells stimulation on expression of selected ABC and OATP transporters The placenta is an organ that plays a key role throughout pregnancy for proper fetal development. One of the important functions provided by the placenta is the transport of substances between the mother and the fetus. This transfer of substances enabled mainly by membrane transporters, which are located on the apical and basal membranes of the syncytiotrophoblast. During various physiological or pathological changes in the human body, their expression and amount can vary significantly. Inflammatory reactions that may occur during pregnancy are also related to these changes, and therefore we have addressed this issue and believed that this condition may alter the expression of placental transporters. The aim of this work was to investigate the changes in the expression of membrane transporters using placental cells on BeWo cell lines and placental villous explants that were stimulated by pro-inflammatory mediators. The change in the expression of individual ATP-binding cassettes,...
137

Function and Dysfunction of Fibrinogen-Like Protein 2 in Reproductive Success and Preeclampsia

Robineau-Charette, Pascale 14 April 2021 (has links)
Fibrinogen-like protein 2 (FGL2) is a known immunomodulator and prothrombinase, expressed by several subsets of immune cells. This thesis explores its potential role during the establishment of pregnancy, in mice, as well as in trophoblast function and in an immune-mediated subtype of preeclampsia (PE), in humans. We first noticed a marked subfertility in Fgl2 knockout (ko) and Fgl2 overexpressing (tg) colonies, where litters were fewer and smaller. To explain this, we mapped spatiotemporal patterns of FGL2 expression in the female reproductive tract and through the estrous cycle. FGL2 is expressed in the ovarian stroma and theca cell layer, peaking shortly before ovulation. Fgl2 ko and tg mice do not show a defect in natural or induced ovulation. FGL2 is expressed in secretory cells of the oviductal epithelium, and Fgl2 ko mice have reduced fertilization efficiency. Fgl2 tg pups are noticeably small, and we find that a reduced ratio of glycogen cells in the junctional zone of their placenta partly explains this. We next investigated the role of FGL2 in trophoblast function, using BeWo and HTR-8/SVneo cell lines. Inflammatory cytokines increase FGL2 expression in BeWo, and FGL2 overexpression promotes syncytialization. We show that it therefore rescues the deleterious effect of inflammation on syncytium formation. In a large cohort of PE and non-PE human placentas, FGL2 is high in a subtype with immune activation, and low in a canonical, anti-angiogenic subtype. Its expression correlates with incidence of chronic inflammatory histopathological lesions, likely driven by immune rejection gene sets. High FGL2 also associates with a high incidence of fibrin deposition in the placenta. Overall, we conclude that FGL2 is involved in several steps of maternal immune adaptation, both before and after pregnancy. Its absence and excess both contribute to mouse subfertility. In the developing and mature placenta, FGL2 is increased by inflammation in the trophoblast and immune compartment of the mature placenta, as a physiological attempt to re-establish immune equilibrium and protect the ongoing pregnancy.
138

Placental Transfer of Nutrients During Gestation in the Viviparous Lizard, Pseudemoia spenceri

Thompson, M. B., Stewart, J. R., Speake, B. K., Russell, K. J., McCartney, R. J. 01 July 1999 (has links)
Energy, ionic, protein and lipid contents and fatty acid profiles for the major lipid classes of freshly ovulated eggs and neonates of the viviparous lizard, Pseudemoia spenceri, were measured. Litter size is 1.7 ± 0.1, with larger females producing larger neonates. Placentotrophy results in approximately 23% more dry matter in the neonates than in the fresh egg. The increase in the quantity of protein and lipid during development is not significant and is reflected in the similarity of energy densities of eggs and neonates. As a percentage of dry matter, neonates have slightly lower proportions of lipid and protein than eggs because of significant uptake of ash, calcium, potassium and sodium, but not of magnesium, across the placenta. The amounts of triacylglycerol and phospholipid are not significantly different between the egg and the neonate, but neonates contain significantly more cholesterol and cholesteryl ester. The amounts of the major fatty acids, palmitic and oleic acids, recovered from the total lipids of the neonate do not differ significantly from the amounts present in the egg lipids, but the neonates contain significantly less linoleic and α-linolenic acids and more palmitoleic, stearic and arachidonic acids than the eggs. The amount of docosahexaenoic acid recovered from the lipids of the neonate is 2.6-times greater than the amount initially present in the egg. P. spenceri has a relatively larger egg and a smaller reliance on placentotrophy than other species in the same genus, all of which have a similar placental morphology. Nevertheless, the pattern of embryonic nutrition includes both obligative and facultative placentotrophy. All the major components of yolk of oviparous species are present in eggs of P. spenceri, but most are augmented during development by placental transfer.
139

Utero-placental blood flow in hypertensive pregnancy and the effect of nifedipine administration

Lindow, S W January 1987 (has links)
Nifedipine, in a 5mg sublingual acute administration, causes a significant fall in the systolic, diastolic and mean arterial pressure in a mixed group of pregnant hypertensives. A concurrent, significant rise in the pulse rate was seen. The utero-placental blood flow index, which is a measure of utero-placental blood flow, was not significantly reduced following the administration of Nifedipine or a placebo. The utero-placental blood flow index was found to be a consistent measure of utero-placental blood flow in resting patients. In the absence of serious side-effects it can be concluded that Nifedipine is a safe therapy in the acute treatment of hypertensive states in pregnancy.
140

Immunomodulator expression in trophoblasts from the feline immunodeficiency virus (FIV)-infected cat as a contributor to placental immunopathology and reproductive failure at early- and late-term pregnancy

Scott, Veronica Lynn 01 May 2010 (has links)
Mother-to-child transmission (MTCT) of HIV accounts for more than 90% of pediatric infections worldwide, yet the mechanism of vertical transfer remains unknown. The feline immunodeficiency virus (FIV)-infected cat is a cost-effective, small-animal model of HIV pathogenesis and MTCT, which produces a high rate of reproductive failure and fetal infection in litters delivered at early- and late-term gestation. Our previous data suggest that FIV infection may dysregulate placental cytokines and compromise pregnancy. We hypothesized that FIV-infection may cause dysregulation of placental cytokine expression, and aberrant expression of these cytokines may potentiate inflammation and transplacental infections. The purpose of this project was to evaluate feline placental immunopathology at the whole and cellular levels during early- and late-term gestation to understand how lentiviruses may perturb placental immune parameters. To determine whether placentas were vulnerable to FIV infection, we quantified the expression of the FIV receptors, CD134 and CXCR4, in RNA extracted from late-term placental tissue. We found higher expression of CD134 and CXCR4 in placentas from successful pregnancies. To evaluate relative cytokine expression in randomly-sampled, whole placental specimens, we quantified representative pro- and anti-inflammatory cytokines and a chemokine. IL-6 and IL-12p35 were increased in early-gestation, FIV-infected queens; IL-6 was increased in late-gestation, FIV-infected queens. To evaluate placental immunopathology at the cellular level, we developed a novel immunohistochemistry method to identify trophoblastic cells selectively. Trophoblasts were collected using laser capture microdissection, and RNA was extracted from captured cells. We detected expression of several anti- and pro-inflammatory cytokines and the chemokine receptor CXCR4 (the FIV co-receptor) in trophoblasts at both stages of gestation. However, we failed to detect expression of other cytokines and CD134, the FIV primary receptor. FIV infection slightly lowered expression of all cytokines at both early and late pregnancy, although only the decrease in IL-5, from early pregnancy, and IL-4 and IL-12p35, from late pregnancy, reached significant levels. Fetal non-viability was associated with decreased trophoblast expression of IL-4, IL-6, IL-12p35, and CXCR4 at early gestation and decreased expression of IL-4, IL-12p35, IL-12p40 at late gestation. Collectively, these data indicate that FIV infection negatively impacts pregnancy outcome and alters placental immunomodulation.

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