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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.
301

Gene expression in the peripartum canine placenta

Fellows, Elizabeth Jane 30 August 2012 (has links)
This research investigated gene expression in the canine placenta during the peripartum period. Previous studies have recognized molecular changes that occur in the placenta around the time of placental release in other species, but no study has looked at gene expression in the late gestation canine placenta. Of particular significance for this thesis work is the groundwork laid for future studies modeling placental abnormalities in dogs (e.g. subinvolution of placental sites) and humans (e.g. preeclampsia, placenta accreta). Despite years of research in multiple species, the exact mechanisms and processes regulating trophoblast invasion and placental release remain unclear. Therefore, the specific objective of this research was to characterize gene expression changes that occur during the peripartum period in the dog using microarray and real-time RT-PCR. Following total RNA isolation, the microarray analysis was performed by hybridizing total RNA to the Canine 2.0 Array (Affymetrix, Santa Clara, CA). Microarray analysis was carried out using the limma and affy packages through the Bioconductor software in the R statistical environment. Differential expression was defined as p ��� 0.05, FDR p ��� 0.10 and a log fold change of ��� 1.2. Following cDNA synthesis, real-time RT-PCR was performed using TaqMan primer and probes that were pre-made and pre-optimized for canine tissues (Applied Biosystems, Carlsbad, CA). Microarray analysis showed differential expression in 18 genes between pre-term and pre-labor sample groups, 38 genes that were differentially expressed between pre-term and parturient samples and no genes that were differentially expressed between pre-labor and parturient samples. Microarray analysis led to the identification of several candidate genes for closer investigation using real-time RT-PCR. These genes included MMP-1, MMP-2, MMP-9, TIMP-2, VEGF-A, Flt-1, CD44, DAG-1, IL-6 and CXCL10. All of these genes have been linked to trophoblast invasion or regression or placental release in a number of species including humans, cattle and rodents. Using real-time RT-PCR, there was a significant difference in MMP-9 mRNA expression in pre-term samples compared to pre- labor and parturient samples (p<0.05). However, there was no significant difference in mRNA expression of MMP-2, TIMP-2, VEGF-A, Flt-1 CD44, DAG-1, IL-6 or CXCL10. Future studies may focus on additional candidate genes identified by microarray that play a role in tissue remodeling at the end of canine gestation such as IL-8, EPHX2, PI3 and SERPINE1. / Graduation date: 2013
302

Characterisation of caspase- 14 in the human placenta : evidence for trophoblast-specific inhibition of differentiation by caspase- 14

White, Lloyd January 2009 (has links)
[Truncated abstract] The placenta forms a barrier regulating the transfer of gases, nutrients and wastes between the mother and the developing conceptus, and also produces hormones affecting both the fetus and the mother. This barrier is formed by the differentiation of the outer layer of the blastocyst- the trophoblast- to facilitate implantation and subsequent invasion of the uterus. The trophoblast consists of an underlying proliferative pool of cytotrophoblasts, which differentiate to replenish the overlying continuous, multi-nucleated syncytiotrophoblast that forms the barrier between the mother and fetus. Moreover, the location of the syncytiotrophoblast directly in contact with the maternal circulation suggests an endothelial role for the trophoblast regulating blood flow, thrombosis and immune cell adhesion. Disruption to the function of the human trophoblast may result in preeclampsia, a maternally manifested disorder of pregnancy characterised by hypertension and proteinurea. Blood flow to preeclamptic placentae is reduced and the cytotrophoblast pool is diminished; however the exact cause (or causes) remains elusive. Many potential causes are hypothesised, including endothelial damage, premature remodelling of maternal spiral arteries, increased oxidative stress and impaired trophoblast differentiation and apoptosis. Caspase-14 is an unusual caspase in that it is not involved in apoptosis. Furthermore, it possesses a limited, predominantly epithelial, tissue distribution. In the epidermis, caspase-14 is expressed in the apical differentiating layers. Here it cleaves profilaggrin to stabilise intracellular keratin intermediate filaments, and indirectly provides natural hydration and UV protection to the corneocytes. Thus, caspase-14 is vital to the maintenance of the barrier function of the skin. ... As differentiation-associated genes were elevated in the absence of caspase-14, this implies that caspase-14 suppresses biochemical trophoblast differentiation. The cytoskeletal keratin network was also examined following RNA Interference. The synthesis of cytokeratin 18 was significantly enhanced after caspase-14 suppression during BeWo differentiation, linking caspase-14 with keratin homeostasis. Therefore caspase-14 suppresses trophoblast differentiation, potentially through modulation of the cytoskeletal keratin filament network. The precise mechanism remains to be elucidated, however the identification of pathways regulated by caspase-14 advances our knowledge of trophoblast differentiation and potential causes of disorders of pregnancy. In summary, caspase-14 appears to be involved in the suppression of differentiation in the human trophoblast. As disorders of pregnancy such as preeclampsia often feature disturbed differentiation and a diminished cytotrophoblast pool, a greater understanding of caspase-14 biology in the human placenta could lead potential therapies for various disorders of pregnancy.
303

Endothelin and the regulation of peripheral and uteroplacental vascular tone during pregnancy /

Ajne, Gunilla, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
304

Factores de riesgo asociados al desprendimiento prematuro de placenta en pacientes cesareadas en el Hospital Nacional Daniel Alcides Carrión de enero del 2012 a diciembre del 2017

Fernández Rodríguez, Liuba January 2018 (has links)
Publicación a texto completo no autorizada por el autor / Realiza un estudio descriptivo transversal que permite verificar los factores de riesgo asociados al desprendimiento prematuro de placenta que tienen relevancia en la población, sobretodo de las gestantes atendidas en el Hospital Nacional Daniel Alcides Carrión, en quienes se puede ofertar medidas preventivo - promocionales de la salud y acciones de control de los principales factores de riesgo. La muestra es de 81 pacientes cesareadas a partir de la revisión de historias clínicas, el traslado de datos es a una ficha de recolección, los datos se tabulan y analizan en el programa estadístico de Microsoft Excel 2010. La edad promedio del grupo de estudio es entre 20 y 35 años (53.08%), el 228.40% son mujeres mayores de 35 años, el 18.52% menores de 20 años; el 12.35% es primíparas, el 80.25% multíparas y el 7.4% gran multíparas. Entre los principales factores de riesgo el 39.51% presenta cuadros hipertensivos del embarazo, seguido por la rotura prematura de membranas con un 22.22%. / Tesis
305

Impact de molécules antivirales contre l'infection à CytoMégaloVirus humaindans des modèles cellulaires et placentaires / Impact of antiviral molecules against human cytomegalovirus replication in cellular and placental models

Andouard, Deborah 18 December 2015 (has links)
Le cytomégalovirus humain (CMVH) est un virus mondialement répandu impliqué dans des pathologies sévères chez les sujets immunodéficients et lors d’infection congénitale. L’arsenal thérapeutique est limité, non dénué de toxicité, et ne pouvant être administrés aux femmes enceintes. De plus, ces traitements favorisent l’émergence de mutations de résistance. Il est donc nécessaire de développer de nouvelles thérapies, mais également de mieux comprendre les mécanismes de l’infection à CMVH lors de la grossesse. Au cours de ce travail de thèse, nous avons travaillé sur différents modèles d’infection virale, premièrement in vitro afin de tester de nouvelles molécules au potentiel antiviral, ciblant l’enzyme cyclooxygénase-2 impliquée dans les processus d’inflammation ; secondairement, ex vivo, sur des explants de placentas de premier et troisième trimestre. Dans ce dernier modèle, nous nous sommes intéressés au profil d’expression des cytokines inflammatoires induites par l’infection à CMVH. Nous avons ainsi testé des nouveaux inhibiteurs de la cyclooxygénase-2 in vitro. L’un d’entre eux, RG193, montre un effet synergique avec le maribavir et la baïcaléine, ce qui est prometteur pour d’éventuelles bithérapies. Concernant le modèle de culture ex vivo, nous avons pu démontrer la viabilité des explants et l’efficacité antivirale de diverses molécules sur l’infection à CMVH. Les résultats préliminaires sur l’expression des cytokines par les placentas infectés montrent des différences notables entre premier et troisième trimestre de grossesse. Cependant, les antiviraux testés semblent avoir peu d’impact sur la régulation des ARN messagers des cytokines pro-inflammatoires MCP-1, TNF-α, IP-10 suite à l’infection. / The human cytomegalovirus (HCMV) is a worldwide common virus involved in diseases in immunocompromised patients, and in congenital infection. Few treatments. Antiviral drugs are limited, not devoid of toxicity, and so cannot be administered to pregnant women. Moreover, they promote the emergence of resistance mutations. Development of new therapies is necessary, also a better understanding of the mechanisms of HCMV infection during pregnancy. In this work, we used different models of viral infection; first in vitro, in order to test new potential antiviral molecules targeting the cyclooxygenase 2 enzyme, which is involved in the inflammation process; secondly an ex vivo model, on first and third trimester placental explants. We also studied the expression profile of inflammatory cytokines induced by the HCMV infection in this model.We have tested new cyclooxygenase 2 inhibitors in vitro. Within them, RG193 shows a synergistic effect with the maribavir and baicalein, which is promising for potential dual therapy. Concerning the ex vivo culture model, we could demonstrate the viability of explants and antiviral efficacy of various molecules on HCMV infection. Preliminary results on the expression of cytokines in infected placentas show differences between first and third trimester of pregnancy. However, antiviral tested appear to have little impact on the regulation of proinflammatory cytokines MCP-1, TNF- α, IP-10 mRNA during infection.
306

CIUR: RELAÇÃO ENTRE O VOLUME PLACENTÁRIO ANTEPARTO POR ECOGRAFIA E PÓS-PARTO POR MACROSCOPIA, E ACHADOS PERINATAIS / IUGR: CORRELATION BETWEEN MEASUREMENTS OF PLACENTAL VOLUME AT ANTENATAL ULTRASOUND AND MACROSCOPIC AVALUATION AFTER BIRTH, AND PERINATAL OUTCOMES

Feltrin, Marcelo Lorensi 17 February 2016 (has links)
Introduction: fetal growth restriction, also called intrauterine growth restriction (IUGR) is a major complication of pregnancy. It is associated with high rates of perinatal morbidity and mortality and childhood, requiring high financial investments to enable adequate care for these newborns. Justification: need for a clinical and sonographic marker, through which one can predict the risk of a fetus likely to have impaired growth, enabling early, and better perinatal care intervention. Purpose: Check the relationship between the measure the placental volume obtained by antenatal ultrasonography, and immediately after birth by macroscopic in fetuses of pregnant women with suspected IUGR and low-risk pregnant women, and perinatal outcomes. Methods: Cross-sectional, prospective, observational study involving 30 low-risk pregnant women and 19 pregnant women of fetuses with suspected IUGR (weigth and/or waist circumference below the 10th percentile for gestational age), treated at Hospital Universitário de Santa Maria (HUSM). The antepartum placental volume, in cm3, was measured by the method described by Azpurua et al, which uses the measurements of length, height and thickness placenta; through the application provided by the same author, it was determined that percentile is the volume found for the given gestational age. The postpartum volume was measured by Archimedes Principle. Perinatal data were obtained from birth records and medical records of newborns. The measures of the variables were analyzed in the form of mean and standard deviation (parametric data), median and quartiles (nonparametric data). Statistical tests: t-Student, Mann-Whitney test, Pearson correlation; It was satisfactory a significance level of 5%, and the data stored and analyzed using the SPSS version 21.0. Results: There was a highly significant difference between the ultrasound and macroscopic placental volume in both groups (p<0,001); was a correlation between placental volume and Apgar in the first minute in the IUGR group (p<0,02); there was a highly significant association between admission to the neonatal intensive care unit, being higher in IUGR group (p<0,01); 94,7% of patients in the group IUGR had placentas with volume below the p10, used in the application. Conclusions: the volume of the placenta after delivery was lower than calculated before birth, in both groups, which is expected, due to the loss of blood through the placenta after placental delivery Adverse perinatal outcomes were present when the placental volume is small but that could be justified by prematurity. Thus, the findings of this study are suggestive of the placental volume in fetuses with IUGR is decreased and associated with few adverse perinatal outcomes. Studies with larger samples may confirm these assumptions. / Introdução: A restrição do crescimento fetal, também denominada crescimento intrauterino restrito (CIUR), é uma das principais complicações da gravidez. Está associada a elevados índices de morbimortalidade perinatal e na infância, requerendo investimentos financeiros elevados para possibilitar assistência adequada a esses recém-nascidos. Justificativa: Necessidade de pesquisa de marcador clínico-ecográfico, através do qual se possa predizer o risco de um feto vir a ter restrição do crescimento ou desfecho gestacional desfavorável, possibilitando intervenção precoce, e melhor assistência perinatal. Objetivos: Verificar relação entre a medida do volume placentário obtida pela ultrassonografia antenatal, e imediatamente após o nascimento pela macroscopia, em gestantes de fetos com suspeita de CIUR e gestantes de baixo risco, e os achados perinatais. Materiais e métodos: estudo transversal, prospectivo e observacional, realizado com 30 gestantes de baixo risco e 19 gestantes de fetos com suspeita de CIUR (peso fetal estimado e/ou circunferência abdominal abaixo do percentil 10 para a idade gestacional), atendidas no Hospital Universitário de Santa Maria (HUSM). O volume placentário anteparto, em cm3, foi mensurado pelo método descrito por Azpurua et al, que utiliza as medidas do comprimento, altura e espessura placentários; através do aplicativo disponibilizado pelo mesmo autor, determinou-se o percentil em que se encontrava o volume, para a determinada idade gestacional. O volume pós-parto foi medido pelo Princípio de Arquimedes. Dados perinatais foram obtidos dos registros de nascimento e prontuários dos recém-nascidos. As medidas das variáveis estudadas foram analisadas sob a forma de média e desvio padrão (dados paramétricos), mediana e quartis (dados não paramétricos). Testes estatísticos: t-Student, Mann-Whitney, correlação de Pearson; foi considerado satisfatório um nível de significância de 5%, e os dados armazenados e analisados no pacote estatístico SPSS versão 21.0. Resultados: houve diferença altamente significante entre o volume placentário ecográfico e macroscópico, em ambos os grupos (p<0,001); foi verificada correlação entre o volume placentário e o APGAR no primeiro minuto no grupo CIUR (p<0,02); existiu associação altamente significante entre internação na UTI-Neonatal, sendo maior no grupo CIUR (p<0,01); 94,7% das pacientes do grupo CIUR tinham placentas com volume abaixo do p10, no aplicativo utilizado. Conclusões: o volume da placenta no pós-parto foi menor que o calculado antes do nascimento, em ambos os grupos, o que é esperado, em razão da perda de sangue pela placenta após dequitação. Desfechos perinatais desfavoráveis estiveram presentes quando o volume placentário é pequeno, mas que poderiam ser justificados pela prematuridade. Assim, os achados do presente estudo são sugestivos de que o volume placentário em fetos com CIUR é reduzido, e associado a alguns desfechos perinatais adversos, mas estudos com amostras maiores são necessários para confirmar essas hipóteses.
307

Estudo da infecção de vírus ZIKA em modelo de explantes de placenta humana / Study of ZIKA virus infection in human placenta explant model

Ribeiro, Milene Rocha [UNESP] 04 June 2018 (has links)
Submitted by MILENE ROCHA RIBEIRO (mrocharibeiro@yahoo.com.br) on 2018-07-12T17:13:42Z No. of bitstreams: 1 tese milene Final 2018.pdf: 2347108 bytes, checksum: e7698208bc381aa0ba18d041fd938d1b (MD5) / Approved for entry into archive by Paula Torres Monteiro da Torres (paulatms@sjrp.unesp.br) on 2018-07-13T18:00:11Z (GMT) No. of bitstreams: 1 ribeiro_mr_do_sjrp.pdf: 2347108 bytes, checksum: e7698208bc381aa0ba18d041fd938d1b (MD5) / Made available in DSpace on 2018-07-13T18:00:11Z (GMT). No. of bitstreams: 1 ribeiro_mr_do_sjrp.pdf: 2347108 bytes, checksum: e7698208bc381aa0ba18d041fd938d1b (MD5) Previous issue date: 2018-06-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O ZIKV é um vírus de RNA, não segmentado, de fita simples e sentido positivo membro da família Flaviviridae. O genoma viral possui uma arquitetura típica de flavivírus, com cerca de 11kb de comprimento, que codifica três proteínas estruturais (Capsídeo, precursor-Membrana, Envelope) e sete proteínas não-estruturais (NS1, NS2A, NS2B, NS3, NS4A, NS4B, NS5). Nas Américas, emergiu rapidamente após surto na ilha da Páscoa, Chile. No Brasil, o surto iniciou em 2015, aumentando consideravelmente casos de microcefalia em recém-nascidos. Aliada a esses casos, também foi observada a ocorrência de síndrome neurológica de Guillain-Barré. Essas associações transformaram o impacto da transmissão e infecções por ZIKV em uma preocupação de saúde pública global. O vírus é transmitido principalmente pelos mosquitos do gênero Aedes, que possuem ampla distribuição e apresentam grandes adaptações a ambientes urbanos. Além de transmissão vetorial, pode ser transmitido via sexual e materno-fetal. O objetivo deste trabalho foi comparar as infecções por uma cepa contemporânea de ZIKV com DENV2 em modelo de explantes de placenta humana a termo, bem como quantificar expressão de citocinas, interferons do tipo I, II e III e marcadores de apoptose induzida via infecção viral. Os resultados demonstram que os explantes da placenta a termo são permissivos e apoiam a infecção por ZIKV. A quantificação da carga viral entre infecções ZIKV e DENV2 foram similares. No entanto, DENV2 apresentou decréscimo na liberação de carga viral em 24 horas pós-infecção. A cinética da replicação viral coincidiu com a expressão de citocinas pró-inflamatórias e o aumento de apoptose no tecido infectado. Clivagem de caspase 3 foi parcialmente dependente de TNF- α e o tratamento com Anti-TNF-α diminuiu significativamente essa ativação mediada por infecção viral. Cumulativamente, este modelo demonstra que os tecidos placentários humanos são alvo de infecção por ZIKV e que a infecção é patogênica para o tecido placentário. Palavras-chave: placenta humana, Flavivírus, explantes, apoptose, interferon, caspase 3. / ZIKV is a non-segmented, single-stranded, positive-sense RNA virus and a member of the Flaviviridae family. Its genome has a typical 11 kB-long flavivirus architecture that encodes three structural proteins (Capsid, PrecursorMembrane, Envelop) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5). In the Americas, the viruses emerged rapidly after outbreak on Pascoa Island, Chile. The outbreak reached Brazil in 2015, substantially increasing cases of microcephaly in newborns. In addition to microcephaly, cases associated with neurological diseases such as GuillainBarré syndrome have made ZIKV a global public health concern. The virus is mainly transmitted by mosquitoes of the genus Aedes, which are widely distributed and which have adapted well great to urban environments. In addition to vector transmission, ZIKV can be transmitted via sexual and maternal-fetal routes, the virus has been isolated is from sperm, amniotic fluid and central nervous systems of stillborn fetuses. The goal of this report was compare ZIKV-infected to DENV2 in full-term human placenta explant model. Quantify expression of cytokines, type I, II and III interferons and markers of induced-apoptosis by viral infection. The results demonstrated that full-term placenta explants are permissive and support ZIKV infection. Viral loads in ZIKV and DENV2 infections were similar. However, DENV2 presented a decrease in viral load release at 24 hours post infection (h.p.i). The kinetics of viral replication coincided with the expression of proinflammatory cytokines and the increase of apoptosis in the infected tissue. Apoptosis was partially dependent on TNF-α. Anti-TNF-α treatment significantly decreased the activated-caspase 3 mediated viral infection. Cumulatively, this model demonstrates that human placental tissues are targets of ZIKV-infection and that the infection is pathogenic to placental tissue.
308

Detecção da expressão gênica de enzimas da gliconeogênese na placenta de fêmeas bovinas / Detection of gene expression of enzymes of gluconeogenesis in the placenta of jamale cattle

Zanardi, Geila Maria 18 December 2008 (has links)
Made available in DSpace on 2016-12-08T16:24:05Z (GMT). No. of bitstreams: 1 PGCV08MA029.pdf: 1036408 bytes, checksum: d90c1227485e2180d47bf0c5aad5a4d1 (MD5) Previous issue date: 2008-12-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A singular feature during mammalian development is the provision of nutrients from the maternal system to the conceptus through the placenta. To the fetus, the placenta consists of a multi-functional organ with an intense metabolism, characterized in an adult as separated functions in multiple organs. This study aimed to verify the presence of key enzymes in the bovine placenta responsible for glyconeogenesis, which is a metabolic pathway used for Dglucose synthesis from non-carbohydrate compounds. Such pathway is common to the liver metabolism used to maintain glucose homeostasis in plasma, especially during fasting or postprandial absorption. No studies on the occurrence of glyconeogenesis in the bovine placenta have been reported thus far. In this study, a qualitative gene expression analysis was carried out for three key glyconeogenic enzymes: fructose-1,6-bisphosphatase (F1,6B), glucose-6- phosphatase (G6-P) e phosphoenolpyruvate carboxikinase (PEP-CK) in the bovine placental tissue at three distinct gestation periods. For that, placentome fragments from 5 pregnant females from each period were used for the detection of transcripts for the three enzymes above by reverse transcription-polymerase chain reaction (RT-PCR). Amplified PCR products obtained for each enzyme from the placenta and adult liver (positive control) were analyzed in 1% agarose gel, followed by purification, DNA cloning e sequencing for confirmation of amplification specificity. The RT-PCR analysis followed by DNA sequencing revealed the presence of all three glyconeogenic enzymes in the bovine placenta from all three gestational periods. Based on our results, the glyconeogenic pathway may occur in the placental tissue in cattle during pregnancy. However, more studies are still needed for the confirmation of the occurrence and temporal importance of the glyconeogenesis in the bovine placenta / Uma característica singular do desenvolvimento dos mamíferos é a provisão de nutrientes do organismo materno por intermédio da placenta. Para o feto, a placenta consiste na combinação, em apenas um órgão, de muitas atividades funcionais, que no adulto são separadas e, além disso, possui um intenso metabolismo. Este trabalho teve como objetivo verificar a expressão de enzimas chave na placenta bovina para a gliconeogênese, que consiste em uma via metabólica capaz de sintetizar D-glicose, utilizando-se compostos que não são carboidratos. Essa via se processa no fígado e é utilizada pelo organismo para manter os níveis glicêmicos normais em condições de jejum e de pós-absorsão. Atualmente não existem estudos sobre a gliconeogênese na placenta bovina. Neste estudo foi avaliada a expressão gênica na placenta bovina de três enzimas gliconeogênicas: frutose-1,6-bisfosfatase (F1,6B), glicose-6-fosfatase (G6-P) e fosfoenolpiruvato carboxiquinase (PEP-CK) nos três trimestres gestacionais. Para tanto, foram utilizados fragmentos de placentônios de 5 fêmeas bovinas para cada terço de gestação para a avaliação da expressão gênica das três enzimas gliconeogênicas após a transcripção reversa e reação em cadeia da polimerase (RT-PCR). Os produtos de PCR amplificados obtidos para cada enzima na placenta bem como para o fígado de animal adulto, que foi utilizado como controle positivo, foram analisados em gel de agarose a 1%, purificados, clonados e seqüenciados para a confirmação da especificidade de amplificação. A análise da expressão gênica através do RT-PCR e o sequenciamento demonstrou a presença de mRNA para as três enzimas gliconeogênicas na placenta bovina nos três períodos gestacionais. Baseado em nossos resultados, é possível que a rota gliconeogênica ocorra no tecido placentário de bovinos durante a gestação. Porém, ainda são necessários mais estudos para a confirmação da ocorrência e importância temporal da gliconeogênese na placenta bovina
309

Expressão das conexinas 32 e 43 em células trofoblásticas da placenta bovina em cultura celular / Expression of the connexins 32 and 43 in trophoblast cells of the bovine placenta in cellular culture

Arlei José Birck 05 December 2007 (has links)
A expressão da conexina 32 e 43 nas células gigantes trofoblásticas foi analisada em condições de cultura celular com e sem influência de hormônios sexuais. Placentônios bovinos foram coletados de vacas prenhes em abatedouro nos diferentes períodos gestacionais e divididos em três grupos, primeiro terço (I), segundo terço (II), terceiro terço (III) e transportados ao laboratório em condições assépticas à temperatura de 4ºC em solução de PBS com antibiótico. No laboratório as células foram isoladas e cultivadas em meio D-MEM com 10% SFB por cinco dias. As detecções das conexinas 32 e 43 foram realizadas através de munofluorescencia, pelo método de amplificação da tiramida-fluoresceina, utilizando anticorpo primário policlonal a imunoglobulina de coelho, anti-conexina 32 e 43 de camundongo. Os resultados mostraram que as células gigantes trofoblásticas expressam conexinas 32 e 43 nos três períodos gestacionais com exceção da Cx32 no primeiro terço gestacional sem adição de hormônios, a qual passou a expressar fluorescência após a adição de hormônios. A distribuição da Cx43 evoluiu com a progressão da gestação, permanecendo limitada ao interior das células gigantes trofoblásticas, sem formar junções comunicantes. O terceiro terço gestacional mostra a Cx43 na CGTT localizada no interior do núcleo. A adição de hormônios ao meio de cultura vem confirmar que a progesterona e o estrógeno podem ter um papel no controle da Cx32. Para Cx43 onde se adicionou progesterona os níveis de expressão foram baixos no início aumentando no decorrer da gestação, o mesmo foi encontrado para o conjugado de progesterona/ estrógeno. Para o estrógeno no grupo I os níveis de expressão foram menores se comparados aos três grupos diminuindo no grupo II e voltando a aumentar no grupo III. / The trophoblast cells expression of connexins 32 and 43 was studied in cell culture conditions with or without influence of sexual hormones. Bovine placentomes were collected from pregnant cows in slaughterhouses in different gestational periods and so divided into three groups, first term (I), second term (II), and third term (III), and transported to the laboratory in aseptic conditions at a temperature of 40C in PBS solution with antibiotics. At the laboratory the cells were isolated and cultivated in D-MEM environment with 10% SFB for five days. The detections of connexins 32 and 43 were achieved through immunofluorescence, by the tyramide-fluorescein amplification method, using a rabbit polyclonal primary antibody anti-connexin 32 and 43 of mice. The results showed that the trophoblast cells expressed connexins 32 and 43 in the three gestational periods with an exception of the Cx32 at the first gestational period. However, after the addition of sexual hormones, they began to express the connexins in the cytoplasm in the first stage. The distribution of the Cx43 evolved with the progression of the gestation, remaining limited to the trophoblast`s cells interior, without formation of gap junctions. The third gestational term shows the Cx43 located inside the nuclei of the CGTT. Addition of hormones in the culture environment confirmed that estrogen and progesterone may have an important action controlling Cx32. For Cx43, the expression was low after prosterone was added to the culture medium, but increased as the gestation evolved, the same was found for a combined compost of estrogen\\ progesterone. For estrogen, in group I the expression levels were inferior when compared to the three groups decreasing in group II and increasing again in group III. We may conclude that the sexual hormes, specially estrogen, affect the expression of connexins in trophoblastic cells.
310

Glicogênio placentário e fetal originados de ovinos gestantes submetidos ou não a tosquia / Glycogen related to placenta and fetus of shorned or not shorned sheep during the gestation

João Carlos Morini Junior 17 December 2007 (has links)
Com intuito de esclarecer a associação do ganho de peso do feto no ato da tosquia, fato este, que diminui a taxa de mortalidade ao nascer, utilizamos vinte e uma ovelhas da raça merino australiano, divididos em 2 grupos com 10 integrantes cada: um tosquiado (OT) aos 70 dias do período gestacional e um segundo mantido como controle (ONT). Destas fêmeas durante o período final de gestação retirou-se a placenta e o feto através do procedimento cirúrgico segundo técnica cesariana convencional. Para efeito comparativo mensurou-se inicialmente as características morfométricas da placenta e dos fetos. Como caracterização da placenta quantificamos o número de placentônios e suas medidas. As amostras de placenta foram fixadas e processadas para microscopia de luz, com inclusão em parafina. A quantificação do glicogênio foi obtida com a mensuração de 5 campos randômicos de cada lâmina produzida seqüencialmente. As análises foram realizadas por efeito comparativo de diferença de coloração por reação histoquímica de P.A.S. Para análise estatística foi utilizado o teste T normal comparativo entre médias. Os resultados macroscópicos indicaram que o tratamento da tosquia não aumentou significativamente os pesos placentários e fetais, e tão pouco as medidas referentes ao placentônio. Nas análises microscópicas, a quantidade média de glicogênio entre as áreas quantificadas no placentônio não apresentaram diferenças significativas, já no fígado na região da tríade portal e no músculo reto houve diferença entre os animais tosquiados e os não tosquiados. Com isto podemos concluir que a tosquia realizada aos 70 dias do período gestacional influência no acumulo de glicogênio no fígado e no músculo reto femural, podendo ser estes os fatos responsáveis pelo aumento do peso dos fetos ao nascer. / In order to clarify the association of weight increase of the fetus in the act of shorn, and remembered that this fact decreases the rate of mortality at birth we tested twenty Merino australian sheep. Animals were divided into 2 groups with 10 members each: shorn (OT) to 70 days of gestational period and a second kept as control (ONT). The placenta and fetus were removed by a surgical procedure of caesarean, according conventional technique. As characterization of the placenta quantification of the placentome numbers and their measures. Samples of placenta were fixed and routinely processed for the light microscopy, with inclusion in paraffin. The quantification of glycogen was obtained with the measurement of 5 fields in each slides produced sequentially. The tests were conducted by comparative effect of a difference in color between the slides and the area covered by the histochemistry PAS reaction For statistical analysis was used the T test (student) and comparison between normal averages. The macroscopic results indicated that the treatment of shorn not significantly increased the fetal and placental weights, and so little measures regarding placentomes. The microscopic analysis, shows that the average between the areas of glycogen quantified in placentome were not different (P <0.05). Already in the liver at the portal triad region and in the rectus femoris muscle were found a significant increase of glycogen deposits (P <0.05). With this results we can conclude that the shorn done at 70 days of gestational period influence on the accumulation of glycogen in the liver and muscle of the fetuses and thus increase the weight of them at birth.

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