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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.
401

Modelos para a produção de eritropoietina recombinante humana in vivo e in vitro com vetores plasmideais em ovinos / Models for the production of human recombinant erythropoietin in vivo and in vitro with plasmidial vectors in ovine

Mariana Ianello Giassetti 24 February 2011 (has links)
Para produção de biofármacos protéicos, como a eritropoietina recombinante humana (EPOrh), são necessárias alterações pós-traducionais adequadas que garantam a sua especificidade e atividade biológica. Essas características são obtidas apenas em biorretores baseados em células eucarióticas, como as da glândula mamária. Sistemas baseados nesse tipo celular, tanto in vivo quanto in vitro, já são utilizados para produção estratégica e viável de proteínas recombinantes biologicamente ativas. Assim, tanto o estabelecimento de novas linhagens de células mamárias que apresentem boa expressão protéica quanto o desenvolvimento de sistemas in vivo que utilizem a estrutura da glândula mamária para essa produção de proteínas recombinantes são de grande valia. O presente trabalho teve como objetivo comparar dois métodos de estabelecimento de uma cultura de células de glândula mamárias ovinas, enzimático e não enzimático, e verificar sua capacidade de expressão das proteínas do leite β-lactoglobulina, α-caseína, β-caseína e κ-caseína mediante o tratamento com SFB (soro fetal bovino) ou SOL (soro de ovelha lactante), na presença ou não de Matrigel. Para isso, foi realizado um experimento in vitro, no qual foi estabelecido o cultivo celular até a passagem 12 (P12) de duas linhagens celulares: digerida (LD) e não digerida (LND). Para a LD na P12 foi observado apenas um tipo celular, o qual era positivo para a marcação com vimentina. Essa linhagem apresentou expressão gênica de β-caseína e β-lactoglobulina apenas quando tratada com meio de cultivo acrescido de SFB, sendo a expressão inferior (P=0,001) ao grupo da LND submetido ao mesmo tratamento. Já a LND, quando tratada com meio adicionado com SFB expressou κ-caseína além da β-caseína e β-lactoglobulina. A troca do SFB do meio de cultivo por SOL aumentou a expressão gênica de β-lactoglobulina (P=0,001) para ambas linhagens. Foi realizada a curva de crescimento para LD e LND na P12 com o meio de cultivo acrescido com SFB ou SOL. Para a LND observou-se o efeito do meio na velocidade de crescimento celular, sendo que foi maior para o grupo tratado com SFB (P<0,05). Para a LD, não ocorreu o efeito do meio na velocidade de crescimento celular (P>0,05), não sendo observada diferença com a LND tratada com SOL (P>0,05). A LND apresentou marcação positiva para a presença de vimentina e citoqueratina. Este trabalho visou, ainda, estabelecer um sistema de produção da EPOrh no leite de ovelhas não transgênicas pela técnica de infusão intra-mamária in vivo de dois plasmídeos diferentes e verificar a secreção qualitativa desta proteína por Western-blotting. Assim, foi feito um experimento in vivo no qual glândulas mamárias de ovelhas foram transfectadas com dois plasmídeos diferentes: ALAC (n=2), BGL (n=2) e controle negativo (n=2). Após a infusão dos plasmídeos, foi realizada a eletroporação de cada teto (3 choques de 500 volts com a duração de 15ms cada, sendo realizada a inversão da polaridade). Os animais foram ordenhados durante 20 dias após a transfecção, porém não foi possível detectar a presença de EPOrh nas amostras de leite analisadas. O limiar de detecção do teste utilizado foi de 67,5pg de EPOrh (Eritromax®) em leite controle negativo de ovelha. Concluindo, foi possível estabelecer o cultivo in vitro das LD e LND com capacidade de expressar proteínas do leite, sendo a expressão da β-lactoglobulina aumentada pelo tratamento com SOL. Ambas as linhagens apresentaram marcação positiva para vimentina, mas apenas LND para citoqueratina. Ainda, para o experimento in vivo, não foi possível detectar a expressão de EPOrh no leite das ovelhas transfectadas com os plasmídeos ALAC e BGL. / Some post-translational modifications are necessary for the production of biopharmaceutical proteins, such as recombinant human erythropoietin (rhEPO), with a good specific action and a high biological activity. These modifications are obtained only by bioreactors based on eukaryotic cell as mammary cells. Bioreactors, in vivo or in vitro, with this kind of cell have been used for a viable and strategic production of biologically active recombinant proteins. For this reason, the establishment of a new line of mammary cells with high milk protein expression and the development of systems for production of recombinant proteins by the mammary gland in vivo are essential studies. One of the main objectives of this study was to compare two methods, enzymatic and non-enzymatic, to establish ovine mammary cells culture and verify their gene expression of milk proteins such as β-lactoglobulin, α-casein, β-casein and κ-casein with different treatments: LOS (lactating ovine serum) or FBS (fetal bovine serum) added to the culture medium, in the presence or absence of Matrigel®. In this manner, an in vitro study was performed and the culture of two lines were established, digested (DL) and non-digested (NDL), of ovine mammary cell until the passage 12 (P12). In DL was observed just one cellular type that was positive for staining with vimentin. This cell line expressed β-lactoglobulin and β-casein genes with the FBS treatment and without Matrigel. The gene expression was lower (P=0,001) when compared to the NDL under the same conditions of culture. Then, the NDL expressed β-lactoglobulin, β-casein and κ-casein genes when treated with FBS without Matrigel. The treatment with LOS in the culture medium increased the gene expression of β-lactoglobulin for both cell lines. The growth curve was determined with both cell lines in P12 with FBS or LOS treatment. For the NDL, the type of medium had effect on the cell growth speed and was highest with the FBS treatment (P<0,05). However, the medium did not have effect on growth speed of LD (P>0,05) and no difference was observed at the NDL treated with LOS (P>0,05). The NDL was positive for staining with vimentin and cytokeratin. The second main objective of this study was to establish an in vivo system for the production of rhEPO in milk of non-transgenic ewes by the intra-mammary infusion of two different plasmids and verify the qualitative milk secretion of this protein by western-blotting. In this way, in the in vivo experiment ovine mammary glands were transfected with two different plasmids: ALAC (n=2), BGL (n=2) and negative control (n=2). Each half udder was filled with plasmid solution and three 3 electric pulses of 500 volts were applied for 15ms each, followed by another three pulses with reversed polarity. The three animals were milked for 20 days after transfection, nevertheless it was not possible to identify rhEPO in any milk sample. The test threshold to identify rhEPO (Eritromax®) in milk from a negative control animal was 67,5pg. In conclusion, the in vitro culture of NDL and DL was established up to the P12 with expression of milk protein and the LOS treatment increased the expression of β-lactoglobulin. The two cell lines culture were positive for staining of vimentina but only NDL was positive for cytokeratin. In the in vivo experiment, rhEPO secretion was not detected in the milk from ewes transfected with ALAC and BGL plasmids.
402

Tratamento de mastite subcl?nica utilizando Terapia Fotodin?mica (PDT). / Treatment of subclinical mastitis through the Photodynamic Therapy (PDT).

Silva, L?via Helena Moreira da 27 February 2009 (has links)
Made available in DSpace on 2016-04-28T20:16:29Z (GMT). No. of bitstreams: 1 2009 - Livia Helema Moreira da Silva.pdf: 9133264 bytes, checksum: 7ce4e3195e33e4e4dd04e40229f544bb (MD5) Previous issue date: 2009-02-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Experiments were carried out to adapt the technical photodynamic therapy (PDT) to the subclinical mastitis treatment in bovine. Two LEDs equipments were tested with manufactured acrylic fibers to penetration in the teats. Different energy densities were tested to development the methodology. The photodynamic therapy using low energy density was efficient to treat subclinical mastitis, it can be seen the reduction of mammary infection. The constructions the acrylic fibers to LEDs equipments were efficient, where it was possible to reach all interior of the mammary treated. The toluidine blue at 2,5% was efficient to light dispersal and in microbial activity. The energy densities (ED) used was efficient to the principal microbial agents of subclinical mastitis found in the present work. Staphylococcus coagulase positive was removed with ED 25J/cm2, Staphylococus coagulase negative were removed with ED 75J/cm2, Bacillus sp was removed with ED 100J/cm2, Streptococcus dysgalactiae bacterial total count was reduced when ED 200J/cm2 was used. / Foram realizados v?rios experimentos para adequar ? t?cnica terapia fotodin?mica (PDT) para o tratamento de mastite subcl?nica em bovinos. Foram avaliados dois aparelhos de LEDs adaptados com fibra de acr?lico para a penetra??o nos tetos. Varias densidades de energia foram testadas para o efeito desejado com o desenvolvimento de uma metodologia pr?pria. A terapia fotodin?mica utilizando baixa densidade de energia para tratar mastite subcl?nica foi eficiente posto que, houve redu??o na infec??o nos quartos mam?rios tratados. As adapta??es para adequa??o dos aparelhos LEDs para tratamento dos tetos afetados com mastite subcl?nica em bovinos foi eficiente permitindo que a irradia??o atingisse todo interior do quarto mam?rio tratado. O agente fotossensibilizante azul de toluidina a 2,5% foi capaz de desencadear o efeito desejado permitindo a dispers?o da luz e estimulando resposta antimicrobiana. As densidades de energia (DE) testadas reduziram os principais agentes microbianos isolados. Staphylococcus coagulase positivos foi eliminado com DE 25J/cm2, Estafilococos coagulase negativos com DE 75J/cm2, Bacillus sp. com DE 100J/cm2 e Streptococcus dysgalactiae diminuiu na contagem bacteriana total quando se utilizou DE 200J/cm2.
403

Patologia molecular dos tumores mamário caninos : expressão de marcadores prognósticos e mioepiteliais

Motta, Adriana Costa da January 2008 (has links)
Os marcadores prognósticos em mastologia têm sido utilizados como apoio diagnóstico para prever o comportamento dos neoplasmas mamários (prognóstico) e determinar a provável resposta ao tratamento pré ou pós-cirúrgico. Estudos têm sido feitos sobre o prognóstico dos tumores mamários caninos (TMCs) que apresentam semelhanças e diferenças com tumores mamários humanos. Além disso, esses tumores exibem, com alta freqüência, proliferação de células mioepiteliais que podem sofrer metaplasia, acompanhada de alterações moleculares. O presente estudo teve o objetivo de verificar a expressão imuno-histoquímica e a associação de diferentes marcadores utilizados como prognósticos nos tumores de mama humana (RE, RP, c-erbB-2 e Ki-67) e marcadores mioepiteliais (p63, CK5 e vimentina) nos TMCs. O primeiro artigo analisa a expressão desses marcadores em 35 tumores encontrados em onze fêmeas caninas nas quais foram identificados tumores malignos múltiplos nas glândulas mamárias. Cada tipo histológico analisado em fêmeas portadoras de tumores múltiplos expressou marcadores prognósticos e mioepiteliais peculiares à sua histogênese, porém houve associação dessa expressão apenas em alguns tipos celulares presentes nos TMCs. Os tumores com componente epitelial carcinomatoso não apresentaram diferenças significativas, no entanto, nos tumores com componente complexo e misto, ocorreu associação entre a expressão da p63, CK5 e vimentina. No conjunto de marcadores estudados, a p63 e a CK5 mostram-se promissoras na elucidação da transformação das células mioepiteliais concomitante à invasão tumoral e com relação à expressão da vimentina que se mostrou bem evidenciada durante a transformação da célula mioepitelial proliferada a célula participante do mesênquima do neoplasma invasor em mamas de caninos, ao menos nos aspectos de expressão molecular e morfológica. O segundo artigo analisa os marcadores mioepiteliais em 82 casos de TMCs malignos. Este estudo comprovou a freqüência e a associação da expressão desses marcadores em determinados tipos histológicos tumorais e celulares, permitindo a identificação das células mioepiteliais em transformação na maior parte dos TMCs malignos, notadamente, os que apresentam componente mesenquimal metaplásico. Mais estudos devem ser feitos na tentativa de verificar a significância da expressão encontrada no comportamento biológico desses tumores. / Prognostic markers in mastology have been used as diagnostic support, to predict the behavior of mammary neoplasias (prognosis) and to determine their possible response to treatment before or after surgery. Studies have been conducted on the prognosis of canine mammary gland tumors (MGTs), which show similarities to and differences from human breast tumors. In addition, these tumors often show proliferation of myoepithelial cells, which may undergo metaplasia, accompanied by molecular alterations. The aim of the present study was to check the immunohistochemical expression and the association between different markers used as prognostic factors in human breast tumors (ER, RP, c-erbB-2 and Ki-67) and myoepithelial markers (p63, CK5 and vimentin) in MGTs. The first article analyzes the expression of these markers in 35 tumors in 11 female dogs, where multiple tumors were identified in the mammary glands. Each histological type analyzed in the female dogs with multiple tumors expressed prognostic and myoepithelial markers that were peculiar to their histogenesis, but the association of this expression was observed only in some cell types of MGTs. Tumors with a carcinomatous epithelial component did not have significant differences, but tumors with complex and mixed components showed association between the expressions of p63, CK5 and vimentin. Of the group of investigated markers, p63 and CK5 proved to be promising tools in elucidating the transformation of myoepithelial cells concomitantly to tumor invasion and in terms of vimentin expression, which was quite pronounced in this transformation from proliferating myoepithelial cells into cells that participate in the mesenchyma of the invasive neoplasia in canine mammary glands, at least with regard to the aspects of molecular and morphological expression. The second article analyzes myoepithelial markers in 82 cases of malignant MGTs. This study corroborated the frequency and association of the expression of these markers in certain histological tumor and cell types, allowing for the identification of myoepithelial cells in transformation in most malignant MGTs, chiefly those with a metaplastic mesenchymal component. Further studies are necessary in order to assess the importance of expression found in the biological behavior of these tumors.
404

Concentração arterial, retenção de metabólitos pela glândula mamária e concentração de CLA no leite de cabras, em resposta à ingestão de fontes de ácidos graxos poliinsaturados ou doses crescentes de óleo de soja / Arterial concentration and mammary gland uptake of metabolites and ClA concentration in goat\'s milk in response to dietary sources of polyunsaturated fatty acids or increasing amounts of soybean oil

Omer Cavalcanti de Almeida 12 June 2008 (has links)
Os objetivos dos experimentos (I e II) foram avaliar os efeitos da inclusão de 2% de fontes de ácidos graxos poliinsaturados (óleo de soja, de linhaça e de peixe) e doses crescentes de óleo de soja (0, 30, 60 e 90 g/dia) sobre o consumo, digestibilidade dos nutrientes no trato digestório total, produção e composição do leite, perfil de ácidos graxos arterial e no leite, concentração arterial e retenção de metabólitos pela glândula mamária das cabras em lactação. Dois meses antes do início do experimento, os animais foram preparados cirurgicamente para exteriorização subcutânea de ambas as artérias carótidas a fim de facilitar a colheita do sangue arterial. Os animais foram alojados em baias individuais onde receberam ração com 40% de silagem de milho e 60% de concentrado, com base na matéria seca. No experimento 1, foram utilizadas quatro cabras Saanen multíparas, produzindo 2,4 kg/dia e com 35 dias de lactação e foram distribuídas em Quadrado Latino 4 x 4 com período experimental de 112 dias. Cada subperíodo teve a duração de 24 dias de adaptação e 4 dias de colheita. Os tratamentos do experimento I foram: a) ração sem adição de óleo (controle); b) controle mais 2% de óleo de soja (OS); c) controle mais 2% de óleo de linhaça (OL) e d) controle mais 2% de óleo de peixe (OP). No experimento 2, foram utilizadas quatro cabras Saanen multíparas, produzindo 3,7 kg/dia e com 35 dias de lactação e foram distribuídas em Quadrado Latino 4 x 4 com período experimental de 112 dias. Cada período teve a duração de 24 dias de adaptação e 4 dias de colheita. Os tratamentos do experimento 2 foram: Ração controle mais o fornecimento oral de doses de óleo de soja (0, 30, 60 e 90 g). No experimento l, a inclusão dos óleos não influenciou o consumo da matéria seca (CMS), da matéria orgânica (CMO), da fibra em detergente neutro (CFDN) e da proteína bruta (CPB), embora tenha havido efeito quando o CMS e o de CMO foram relacionados com o peso metabólico. O CEE foi influenciado pelos óleos. As digestibilidades da MS, MO, FDN, PB e do EE no trato digestório total não foram influenciadas. Não houve efeito na produção de leite e nos seus componentes (gordura, proteína, lactose, sólidos totais e extrato seco desengordurado), embora tenha havido efeito no perfil de ácidos graxos. O óleo de peixe promoveu elevação (350%) na concentração do ácido vacênico (C18:1 t11) no leite, alem de maiores elevações na concentração arterial do ácido vacênico (376%) e na relação C18:1 t11, C18:2 c9, t11 (1111%). A adição dos óleos nas rações, não influenciou a concentração arterial e a retenção de metabólitos (glicose, ß- hidroxibutirato) pela glândula mamária. No experimento 2, as doses de óleo de soja alteraram o CMS e o CMO, assim como a digestibilidade da MS e do EE. Não houve efeito na produção de leite, porém a concentração de gordura diminuiu com as doses de óleo. Os perfis de ácidos graxos no leite e no sangue arterial foram influenciados pelas doses de óleo de soja. O aparecimento do C18:2 t10, c12 no leite culminou com a redução de gordura (558%). A dose de 90 g propiciou a elevação do ácido vacênico (810%), ao contrário do C18:2 c9, t11, que diminuiu. A concentração arterial e a retenção mamária de glicose e ßhidroxibutirato não foram influenciadas pelas doses de óleo de soja. / The objectives of these studies were to evaluate the effects of adding 2% palyunsaturated fatty acid sources (soybean, linseed and fish oils) or soybean oil doses (O, 30, 60 or 90 g/day) on dry matter intake, apparent nutrient digestibilities, milk yield, milk composition, arterial and milk fatty acid profiles, and metabalite uptake by the mammary gland in lactating goats. Animais were housed in individual tie stalls and received diets containing 40% com silage and 60% concentrate (dry matter basis). In Experiment \"four Saanen goats producing 2.4 kg/day and 38 days in milk were used in a 4 x 4 latin Square design during 112 days. Each period lasted 28 days (24d for adaptation and 4d for sampling). Four experimental diets were used: a) Control diet (CO, without additional oil); b) CO plus 2% soybean ail (OS); c) CO plus 2% linseed oil (Ol); ar d) CO plus 2% fish oil (OP). Experiment 11, four Saanen goats producing 3.7 kg/day and 32 days in milk were used in a 4 x 4 latin Square design during 112 days. Each period lasted 28 days (24d for adaptation and 4d for sampling). Gaats were fed a control diet plus an oral daily dose (O, 30, 60 or 90 g) of soybean oi!. In experiment I, ail sources did not influence intakes of dry matter, organic matter, or neutral detergent fiber. Hawever, an oil effect was observed when expressed on the basis of metabolic weight. The OM, OM, NOF, CP, and EE apparent digestibilities were not affected by treatment. Production of milk components (fat, protein, lactose, total solids, and non-fat salids) was nat different among treatments, although an effect in fatty acid profile was observed. Fish oil increased arterial and milk vaccenic acid t11 C18:1 concentrations by more than 350%, and increased the t11 C18:1: c9,t11 C18:2 ratio in the arterial blood by 1111 %. Gil addition did not influence arterial blood concentration and mammpry gland uptake of glucase or l3-hydroxybutyrate. Experiment li showed that supplementation of saybean oil resulted in changes of OM, OM, and EE intakes, but intake of the NOF and CP were not affected. Oigestibility of OM and EE were influenced by soybean ai!. Oaily milk production was not influenced, but milk fat was reduced by soybean oi!. Milk and arterial fatty acids profiles were influenced by saybean oi!. As the concentration of t10,c12 C18:2 increased in arterial blood, a reduction (558%) in milk fat was observed and also a decrease in ô9-desaturase activity was detected. The 90 9 supplement of soybean oil resulted in an elevation (810%) in the milk vaccenic concentratian; conversely (c9,t11 C18:2), decreased. The. arterial blood concentration and mammary gland uptake of glucose and l3-hydroxybutyrate were not affected by soybean oil.
405

Tratamento de mastite subcl?nica utilizando Terapia Fotodin?mica (PDT) / Treatment of subclinical mastitis through the Photodynamic Therapy (PDT)

SILVA, L?via Helena Moreira da 27 February 2009 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-15T18:23:07Z No. of bitstreams: 1 2009 - L?via Helena Moreira da Silva.pdf: 9761965 bytes, checksum: 0fa6815cc4bc10c43d8eea0b989dc84d (MD5) / Made available in DSpace on 2017-08-15T18:23:07Z (GMT). No. of bitstreams: 1 2009 - L?via Helena Moreira da Silva.pdf: 9761965 bytes, checksum: 0fa6815cc4bc10c43d8eea0b989dc84d (MD5) Previous issue date: 2009-02-27 / CNPq / Experiments were carried out to adapt the technical photodynamic therapy (PDT) to the subclinical mastitis treatment in bovine. Two LEDs equipments were tested with manufactured acrylic fibers to penetration in the teats. Different energy densities were tested to development the methodology. The photodynamic therapy using low energy density was efficient to treat subclinical mastitis, it can be seen the reduction of mammary infection. The constructions the acrylic fibers to LEDs equipments were efficient, where it was possible to reach all interior of the mammary treated. The toluidine blue at 2,5% was efficient to light dispersal and in microbial activity. The energy densities (ED) used was efficient to the principal microbial agents of subclinical mastitis found in the present work. Staphylococcus coagulase positive was removed with ED 25J/cm2 removed with ED 75J/cm2, Staphylococus coagulase negative were , Bacillus sp was removed with ED 100J/cm2 , Streptococcus dysgalactiae bacterial total count was reduced when ED 200J/cm2 was used. / Foram realizados v?rios experimentos para adequar ? t?cnica terapia fotodin?mica (PDT) para o tratamento de mastite subcl?nica em bovinos. Foram avaliados dois aparelhos de LEDs adaptados com fibra de acr?lico para a penetra??o nos tetos. Varias densidades de energia foram testadas para o efeito desejado com o desenvolvimento de uma metodologia pr?pria. A terapia fotodin?mica utilizando baixa densidade de energia para tratar mastite subcl?nica foi eficiente posto que, houve redu??o na infec??o nos quartos mam?rios tratados. As adapta??es para adequa??o dos aparelhos LEDs para tratamento dos tetos afetados com mastite subcl?nica em bovinos foi eficiente permitindo que a irradia??o atingisse todo interior do quarto mam?rio tratado. O agente fotossensibilizante azul de toluidina a 2,5% foi capaz de desencadear o efeito desejado permitindo a dispers?o da luz e estimulando resposta antimicrobiana. As densidades de energia (DE) testadas reduziram os principais agentes microbianos isolados. Staphylococcus coagulase positivos foi eliminado com DE 25J/cm2, Estafilococos coagulase negativos com DE 75J/cm2, Bacillus sp. com DE 100J/cm2 e Streptococcus dysgalactiae diminuiu na contagem bacteriana total quando se utilizou DE 200J/cm
406

Estudo da interação entre vias de sinalização dos estrógenos e fatores de crescimento  no controle da transcrição dos genes HNRPK, PAWR e PHLDA1 / Study to evaluate the crosstalk between estrogens and growth factors pathways on the transcriptional regulation of HNRPK, PAWR and PHLDA1.

Garcia, Simone Aparecida de Bessa 18 December 2009 (has links)
A interação entre as vias de sinalização dos estrógenos e fatores de crescimento está relacionada a maior agressividade dos tumores de mama. Assim, o objetivo deste trabalho foi verificar a interação entre as vias do E2 e do EGF no controle da expressão dos genes HNRPK, PAWR e PHLDA1 nas células MCF-7 (ER+) e MDA-MB-231 (ER-). Nas células MCF-7, o EGF e o E2 diminuíram a expressão do PAWR e aumentaram a expressão de PHLDA1. A inibição do ER pelo ICI resultou no aumento da expressão de PAWR sendo que a adição do E2 ou do EGF diminuiu sua expressão sem retomar os níveis observados nos tratamentos com E2 ou EGF isoladamente. Para o gene PHLDA1, o efeito do E2 e do EGF não variou após o tratamento com ICI. Nas células MDA-MB-231, a ação do EGF foi mais efetiva sobre a expressão de PAWR. A via ERK1/2 é importante na ativação do ER pelo EGF. O efeito do EGF sobre o PHLDA1 ocorre através da ativação das vias ERK1/2 e p38 MAPK. Estes resultados mostram a interação entre as vias do E2 e do EGF no controle da expressão do PAWR, mas não do PHLDA1. / The crosstalk between estrogens and growth factors pathways has been associated with breast cancer aggressiveness. Based on this, the present study aimed to determine the possible crosstalk between E2 and EGF pathways on the HNRPK, PAWR and PHLDA1 expression regulation in MCF-7 (ER+) and MDA-MB-231 (ER-) cells. In MCF-7 cells, treatments with E2 and EGF decreased PAWR expression and increased PHLDA1 expression. The ER inhibition by the ICI treatment resulted in increased PAWR expression. The E2 or EGF addition down-regulated its expression without a return to the levels observed after the E2 or EGF treatments alone. To the PHLDA1 gene, the effect of E2 and EGF treatments did not change after the ICI treatment. In MDA-MB-231 cells, the EGF effect was more significant on the PAWR gene expression control. The ERK1/2 pathway is important to the ER activation by EGF. The EGF effect over the PHLDA1 is dependent on the ERK1/2 and p38 MAPK activation. These findings suggest a crosstalk between E2 and EGF pathways on the PAWR expression control but not to PHLDA1.
407

"Estudo comparativo entre os enxertos arteriais compostos e os enxertos arteriais isolados na revascularização do miocárdio: análise do fluxo sangüíneo e da reserva de fluxo coronariano com Doppler intravascular" / Comparative study between composite and independent arterial grafts in myocardial revascularization : blood flow and coronary flow reserve analysis by intravascular Doppler

Castro Neto, Josué Viana de 30 November 2005 (has links)
O objetivo é comparar o fluxo sanguíneo total (FS) e a reserva de fluxo coronariano (RFC) aos ramos revascularizados pelas artérias torácica interna esquerda (ATIE) e radial (AR) nos enxertos compostos com os enxertos isolados. Foi realizado um ensaio clínico randomizado de 42 pacientes que foram distribuídos em grupo A ou ATIE e AR composta em Y(n=14), grupo B ou ATIE e AR composta modificada(n=14) e grupo C ou ATIE pediculada para DA e AR aorto-coronariana(n=14). Os pacientes foram submetidos a fluxometria no pós-operatório imediato. A RFC foi de 2,1 ± 0,44, 1,96 ± 0,3 e 2,06±0,42 nos grupos A,B e C, (p=0.7208 A, B x C) e o FS, em ml/min, foi 110±30, 145±59 e 136±58, respectivamente (p=0.3232 A,B x C). Concluindo, não houve diferença significativa do FS total e nem da RFC nos grupos estudados / The objective is to compare the total blood flow (Bf) and coronary flow reserve (CFR) to the left coronary branches that were revascularized with left internal thoracic (LITA) and radial artery (RA) in composite and independent arterial grafts. A randomized trial was realized and 42 patients assigned in group A or composite LITA-RA in a Y configuration (n=14), group B or modified composite LITA-RA(n=14) and group C or pedicled LITA to LAD and aorto-coronary RA (n=14). Patients were submitted to postoperative Bf velocity analysis. CFR was 2,1 ± 0,44, 1,96 ± 0,3 e 2,06±0,42 in groups A,B and C (p=0.7208 A, B x C) and Bf, in ml/min, was 110±30, 145±59 and 136±58, respectively (p=0.3232 A, B x C). In conclusion there was no difference in Bf and CFR in the groups studied
408

Physiologie et physiopathologie des effets membranaires du récepteur des œstrogènes alpha (ERα) dans la glande mammaire / Physiology et physiopathology of membrane estrogen receptor alpha (ERα) in mammary gland

Gagnac, Laurine 05 March 2018 (has links)
It is well established that the 17-estradiol is involved in the development and homeostasis of reproductive and extra-reproductive tissues, particularly the mammary gland. Estradiol classically binds to Estrogen Receptor (ERα), which is a member of the nuclear receptor superfamily. ER mediates nuclear (transcription) and plasma membrane (signaling) ERα function. Interestingly, the membrane initiated steroid signaling (MISS) required a post translational modification of the receptor: palmitoylation of the human Cys-447 or the murine Cys-451 counterpart. The main objectives of my PhD thesis were to decipher the physiological role of membrane ERα in mammary gland development and to understand how the membrane ER signaling impact breast cancer. To do so, we used the transgenic mouse model C451A-ER in which the single point mutation (C451A) was introduced to abolish palmitoylation of ER (membrane addressing signal). We demonstrate that the point mutation of the palmitoylation site of ER alters the paracrine signaling of luminal epithelial cells and by consequence the repopulation properties of the mammary stem cells. We also studied the involvement of the membrane effects of the Estrogen Receptor ERα in the 17β-estradiol response dose of the mammary gland. Finally, by breeding the C451A-ER mice with the widely used transgenic mice model of tumorigenesis (PyMT), we provide the first evidence that the membrane ERα influences tumorigenesis. These findings pave the way on an unexpected role of non-genomic function of ERα in the mammary gland physiology and physiopathology. / It is well established that the 17-estradiol is involved in the development and homeostasis of reproductive and extra-reproductive tissues, particularly the mammary gland. Estradiol classically binds to Estrogen Receptor (ERα), which is a member of the nuclear receptor superfamily. ER mediates nuclear (transcription) and plasma membrane (signaling) ERα function. Interestingly, the membrane initiated steroid signaling (MISS) required a post translational modification of the receptor: palmitoylation of the human Cys-447 or the murine Cys-451 counterpart. The main objectives of my PhD thesis were to decipher the physiological role of membrane ERα in mammary gland development and to understand how the membrane ER signaling impact breast cancer. To do so, we used the transgenic mouse model C451A-ER in which the single point mutation (C451A) was introduced to abolish palmitoylation of ER (membrane addressing signal). We demonstrate that the point mutation of the palmitoylation site of ER alters the paracrine signaling of luminal epithelial cells and by consequence the repopulation properties of the mammary stem cells. We also studied the involvement of the membrane effects of the Estrogen Receptor ERα in the 17β-estradiol response dose of the mammary gland. Finally, by breeding the C451A-ER mice with the widely used transgenic mice model of tumorigenesis (PyMT), we provide the first evidence that the membrane ERα influences tumorigenesis. These findings pave the way on an unexpected role of non-genomic function of ERα in the mammary gland physiology and physiopathology.
409

Effects of sex steroids and tamoxifen on matrix metalloproteinase activity and generation of endostatin in the breast

Nilsson, Ulrika W. January 2007 (has links)
Sex steroids are inevitable in women. However, long-term exposure to sex steroids increases the risk of breast cancer. A complete understanding of sex steroid control of the breast and how it relates to breast cancer risk is still lacking. Angiogenesis and proteolytic enzyme activity are crucial for the process by which tumors evolve into a vascularized, invasive phenotype. Matrix metalloproteinases are potent matrixdegrading enzymes that affect several steps in tumor progression including angiogenesis. In the female reproductive organs, sex steroids regulate angiogenesis and MMP activity, yet little is known how sex steroids affect these crucial events in normal and malignant breast tissue. This thesis elucidates a link between sex steroids, MMP activity, and angiogenesis. It is shown that estradiol down-regulates while tamoxifen up-regulates the protein expression and activity of MMP-2 and MMP-9 in human breast cancer cells in vitro and in human breast cancer xenografts in vivo. The results further suggest that a biological consequence of this regulation may be modulation of tumor angiogenesis. The net effect of adding tamoxifen to estradiol treatment was an increase in extracellular levels of the endogenous angiogenesis inhibitor endostatin and decreased levels of the tumor promoter TGF-β1 compared to estradiol treatment only. This was accompanied by reduced vasculature and decreased tumor growth. Similarly, a regulatory effect of estradiol and tamoxifen on endostatin generation was observed in normal human breast tissue by whole-tissue culture and microdialysis in human breast tissue in situ. In conclusion, the results presented in this thesis suggest previously unknown mechanisms of action of estradiol and tamoxifen in breast cancer and in normal human breast tissue, and novel means by which estradiol may tip the scale to favor angiogenesis. This knowledge may be important for the understanding of sex steroid dependent breast carcinogenesis and in the future development of tissue-specific preventive as well as therapeutic strategies against breast cancer.
410

Riboflavin Transporters and Breast Cancer Resistance Protein: Cimetidine-Riboflavin Interactions in the Mammary Gland

Dedina, Liana 28 November 2012 (has links)
Mother's milk provides multiple benefits to the offspring. However, xenobiotics transferred into breast milk may pose a risk to the nursing infant. The breast cancer resistance protein (BCRP) actively transports xenobiotics into breast milk. BCRP also transports nutrients, like riboflavin, and together with recently identified riboflavin transporters (RFT), may provide a mechanism for riboflavin secretion into breast milk. Expression of RFT in the mammary gland remained unknown. Our objective was to characterize Bcrp and Rft mRNA expression in the mammary gland of FVB/N mice, and investigate a strategy to decrease excretion of BCRP-transported xenobiotics into the milk using riboflavin intervention. Rft and Bcrp mRNA were upregulated in the mammary gland of lactating mice. An intravenous riboflavin administration significantly reduced the levels of BCRP-transported cimetidine in milk. This study demonstrates the use of riboflavin to exploit the function of mammary BCRP in order to reduce xenobiotic secretion into breast milk.

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