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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.
91

Identificação imunohistoquímica de receptores para hormônio luteinizante, estrôgeno e progesterona no trato reprodutivo extragonadal da égua / Immunohistochemical identification of luteinizing, estrogen and progesterone receptors in the extra-gonadal reproductive tract of mares

Esmeraldino, Anamaria Telles January 2012 (has links)
O objetivo deste trabalho foi verificar a presença e a localização de receptores para hormônios esteróides e gonadotróficos, através da técnica de imunohistoquímica, pelo método de peroxidase-antiperoxidase (PAP), nos diferentes tecidos que compõe o trato genital da égua e a variação de reatividade destes receptores durante o ciclo estral e no anestro fisiológico. Também se objetivou verificar se há diferença de reatividade em éguas com e sem endometrose. Foram coletadas amostras de útero, cérvice e oviduto, de 41 éguas sem raça definida e com histórico reprodutivo desconhecido, em um abatedouro. Quinze éguas se encontravam em estro, dezoito em diestro e oito éguas em anestro. Concluiu-se que a intensidade e a distribuição da coloração para os receptores de estrógeno (RE), progesterona (RP) e hormônio luteinizante (RLH) variaram de acordo com o tipo de célula e o estágio do ciclo estral. Nas amostras de endométrio observou-se imunorreatividade alta no epitélio luminal para RE e RP tanto no estro quanto no diestro; o epitélio glandular, estroma e miométrio mostraram reatividade moderada para os dois receptores durante as duas fases. Durante o anestro os resultados foram semelhantes aos encontrados durante a fase cíclica. Na avaliação da reatividade para RLH, durante o estro e diestro, o epitélio luminal mostrou reatividade de fraca a moderada, mas no diestro houve maior reatividade média. O epitélio glandular apresentou menor reatividade do que o luminal. No miométrio a coloração foi fraca durante todo o ciclo. Durante o anestro a reatividade foi fraca no epitélio luminal, ausente em quase todas as amostras no epitélio glandular e de fraca a ausente no miométrio. Neste experimento, não foi observada diferença significativa de reatividade entre os endométrios com e sem endometrose, mas as áreas afetadas mostraram coloração assíncrona para RE, RP e RLH. Na cérvice, foi observada imunorreatividade moderada a alta para RE e RP no epitélio luminal, no estroma e no músculo. A intensidade de coloração das células epiteliais e musculares variou pouco entre o estro e o diestro, mas durante o anestro houve maior reatividade no tecido muscular e no estroma. Foi observada reatividade para RLH no epitélio e camada muscular, sem variação significativa nas fases do ciclo. A intensidade de coloração foi de fraca a moderada no epitélio e fraca na camada muscular. No oviduto, observou-se imunorreatividade para RE e RP nos três tecidos, durante a fase cíclica e o anestro. No epitélio, os valores encontrados foram de moderados a altos, sem variação significativa nas três fases. A coloração das células epiteliais do oviduto foi nitidamente irregular, com o núcleo muito corado no que parecem ser células secretoras e pouco corado ou sem coloração nas células ciliadas, refletindo provavelmente as diferentes funções das células epiteliais neste órgão. No estroma a reatividade foi moderada durante a fase luteal, mostrando reatividade mais alta no estro e no anestro. A camada muscular apresentou reatividade máxima para RE no estro e no diestro. A reatividade para RLH no epitélio luminal foi de fraca a moderada durante todo o ciclo. No músculo também foi observada reatividade, porém bem mais fraca do que no epitélio. Durante o anestro somente três das oito amostras apresentaram reatividade no tecido muscular. No diestro foi observada maior reatividade do que no estro. Os resultados do presente estudo evidenciam, pela primeira vez, a presença de receptores para LH nos diferentes tecidos do trato reprodutor extragonadal da égua. Embora existam relatos da expressão e localização de RE e RP no endométrio equino, esta é a primeira vez que se utiliza a técnica de imunohistoquímica para localizar estes receptores na cérvice e no oviduto desta espécie. Foi observada variação individual bastante acentuada entre as amostras, em uma mesma fase cíclica. Provavelmente estes resultados sejam o reflexo da variação entre o dia do ciclo em que os animais se encontravam, bem como da complexidade dos mecanismos envolvidos na presença desses receptores. Os achados deste estudo indicam que tanto os hormônios gonadais quanto o LH atuam por meio de seus receptores nos diferentes tecidos do trato reprodutivo da égua, podendo servir para a elaboração de novas estratégias para melhorar a eficiência reprodutiva nesta espécie. / The aim of this study was to demonstrate the presence and localization of gonadotropic and steroid hormone receptors, in different tissues of the mare genital tract and the different reactivity to these receptors during the endometrial cycle and physiologic anestrus. Another objective was to compare the reactivity to theses receptors in mares with and without endometrosis. Immunohistochemistry was performed using the peroxidase anti-peroxidase technique (PAP). Uterus, cervix and oviduct of 41 criollo mares were collected in an abattoir. There was variation in the intensity of the staining and distribution for estrogen receptors (PR), progesterone receptors (PR) and luteinizing hormone receptors (LHR) with the endometrial cycle and different tissues. The endometrial surface epithelial cells were stained strongly for ER and PR in the estrous and dioestrus; glandular epithelial cells, stromal cells and smooth muscle cells of the myometrium had moderate staining for ER and PR during these two phases and in anestrus too. The immunoreactive score for LHR in the surface epithelial cells during endometrial cycle was weak to moderate but, in general, strong staining was observed in dioestrus. More weak staining intensity was observed in the glandular epithelial cells than luminal epithelial cells. Smooth muscle cells of the myometrium showed weak staining for LHR throughout the endometrial cycle. During the anestrus, the immunoreactivity score was weak in the surface epithelial cells. In general, the glandular epithelium was not stained. Myometrium cells were weak to not staining for LHR, in this phase. In this study there was no significant difference in immunoreactive score for ER, PR and LHR in endometrium with or without endometrosis but fibrotic glands showed different expression patterns of ER, PR and LHR, could evidence for functionally glandular maldifferentiation in endometrosis. The cervical epithelial surface, stromal cells and smooth muscle cells were moderate to strongly staining for ER and PR, with little variation throughout the endometrial cycle but the immunorectivity was strongest during the anestrus in muscular and stromal cells. Surface epithelial cells of cervix were weak to moderate stained for LHR; smooth muscle cells showed weak staining for these receptors. There was no variation during cycle. In the oviduct, epithelial, stromal and muscle cells showed reactivity for RE and RP, during cycle and anestrus. Epithelial cells were moderate to strongly staining for these receptors, with evident irregularity in different types of cells. Apparently ciliated epithelial cells were stained but the intensity was much less than that observed in nonciliated epithelial cells, probably reflecting different functions of these cells. Stromal cells showed moderate staining during dioestrus and strongest reactivity in estrous and anestrus; muscle cells showed strong reactivity for ER throughout the cycle. The reactivity for LHR was weak to moderate throughout the cycle in the epithelial cells and weak in the muscle cells. During anestrus only three strains of muscle cells showed reactivity for LHR. In dioestrus the intensity was strongest. These findings evidence for the firs time the presence for LHR in extra-gonadal reproductive organs of mare. Though there were reports of ER and PR expression in equine endometrium, this is the first report of localization of these receptors in cervix and oviduct of mare using immunohistochemistry. It was found marked individual variation among the strains. These results probably were caused by the variation among the day of cycle and the complexity of mechanisms involved in the presence of these receptors. The findings of the present study allow us to infer that the ovarian steroid hormones nad LH function through their receptors in different tissues of mare reproductive tract, can help us to elaborate new strategies to improve the reproductive efficiency in this specie.
92

Identificação imunohistoquímica de receptores para hormônio luteinizante, estrôgeno e progesterona no trato reprodutivo extragonadal da égua / Immunohistochemical identification of luteinizing, estrogen and progesterone receptors in the extra-gonadal reproductive tract of mares

Esmeraldino, Anamaria Telles January 2012 (has links)
O objetivo deste trabalho foi verificar a presença e a localização de receptores para hormônios esteróides e gonadotróficos, através da técnica de imunohistoquímica, pelo método de peroxidase-antiperoxidase (PAP), nos diferentes tecidos que compõe o trato genital da égua e a variação de reatividade destes receptores durante o ciclo estral e no anestro fisiológico. Também se objetivou verificar se há diferença de reatividade em éguas com e sem endometrose. Foram coletadas amostras de útero, cérvice e oviduto, de 41 éguas sem raça definida e com histórico reprodutivo desconhecido, em um abatedouro. Quinze éguas se encontravam em estro, dezoito em diestro e oito éguas em anestro. Concluiu-se que a intensidade e a distribuição da coloração para os receptores de estrógeno (RE), progesterona (RP) e hormônio luteinizante (RLH) variaram de acordo com o tipo de célula e o estágio do ciclo estral. Nas amostras de endométrio observou-se imunorreatividade alta no epitélio luminal para RE e RP tanto no estro quanto no diestro; o epitélio glandular, estroma e miométrio mostraram reatividade moderada para os dois receptores durante as duas fases. Durante o anestro os resultados foram semelhantes aos encontrados durante a fase cíclica. Na avaliação da reatividade para RLH, durante o estro e diestro, o epitélio luminal mostrou reatividade de fraca a moderada, mas no diestro houve maior reatividade média. O epitélio glandular apresentou menor reatividade do que o luminal. No miométrio a coloração foi fraca durante todo o ciclo. Durante o anestro a reatividade foi fraca no epitélio luminal, ausente em quase todas as amostras no epitélio glandular e de fraca a ausente no miométrio. Neste experimento, não foi observada diferença significativa de reatividade entre os endométrios com e sem endometrose, mas as áreas afetadas mostraram coloração assíncrona para RE, RP e RLH. Na cérvice, foi observada imunorreatividade moderada a alta para RE e RP no epitélio luminal, no estroma e no músculo. A intensidade de coloração das células epiteliais e musculares variou pouco entre o estro e o diestro, mas durante o anestro houve maior reatividade no tecido muscular e no estroma. Foi observada reatividade para RLH no epitélio e camada muscular, sem variação significativa nas fases do ciclo. A intensidade de coloração foi de fraca a moderada no epitélio e fraca na camada muscular. No oviduto, observou-se imunorreatividade para RE e RP nos três tecidos, durante a fase cíclica e o anestro. No epitélio, os valores encontrados foram de moderados a altos, sem variação significativa nas três fases. A coloração das células epiteliais do oviduto foi nitidamente irregular, com o núcleo muito corado no que parecem ser células secretoras e pouco corado ou sem coloração nas células ciliadas, refletindo provavelmente as diferentes funções das células epiteliais neste órgão. No estroma a reatividade foi moderada durante a fase luteal, mostrando reatividade mais alta no estro e no anestro. A camada muscular apresentou reatividade máxima para RE no estro e no diestro. A reatividade para RLH no epitélio luminal foi de fraca a moderada durante todo o ciclo. No músculo também foi observada reatividade, porém bem mais fraca do que no epitélio. Durante o anestro somente três das oito amostras apresentaram reatividade no tecido muscular. No diestro foi observada maior reatividade do que no estro. Os resultados do presente estudo evidenciam, pela primeira vez, a presença de receptores para LH nos diferentes tecidos do trato reprodutor extragonadal da égua. Embora existam relatos da expressão e localização de RE e RP no endométrio equino, esta é a primeira vez que se utiliza a técnica de imunohistoquímica para localizar estes receptores na cérvice e no oviduto desta espécie. Foi observada variação individual bastante acentuada entre as amostras, em uma mesma fase cíclica. Provavelmente estes resultados sejam o reflexo da variação entre o dia do ciclo em que os animais se encontravam, bem como da complexidade dos mecanismos envolvidos na presença desses receptores. Os achados deste estudo indicam que tanto os hormônios gonadais quanto o LH atuam por meio de seus receptores nos diferentes tecidos do trato reprodutivo da égua, podendo servir para a elaboração de novas estratégias para melhorar a eficiência reprodutiva nesta espécie. / The aim of this study was to demonstrate the presence and localization of gonadotropic and steroid hormone receptors, in different tissues of the mare genital tract and the different reactivity to these receptors during the endometrial cycle and physiologic anestrus. Another objective was to compare the reactivity to theses receptors in mares with and without endometrosis. Immunohistochemistry was performed using the peroxidase anti-peroxidase technique (PAP). Uterus, cervix and oviduct of 41 criollo mares were collected in an abattoir. There was variation in the intensity of the staining and distribution for estrogen receptors (PR), progesterone receptors (PR) and luteinizing hormone receptors (LHR) with the endometrial cycle and different tissues. The endometrial surface epithelial cells were stained strongly for ER and PR in the estrous and dioestrus; glandular epithelial cells, stromal cells and smooth muscle cells of the myometrium had moderate staining for ER and PR during these two phases and in anestrus too. The immunoreactive score for LHR in the surface epithelial cells during endometrial cycle was weak to moderate but, in general, strong staining was observed in dioestrus. More weak staining intensity was observed in the glandular epithelial cells than luminal epithelial cells. Smooth muscle cells of the myometrium showed weak staining for LHR throughout the endometrial cycle. During the anestrus, the immunoreactivity score was weak in the surface epithelial cells. In general, the glandular epithelium was not stained. Myometrium cells were weak to not staining for LHR, in this phase. In this study there was no significant difference in immunoreactive score for ER, PR and LHR in endometrium with or without endometrosis but fibrotic glands showed different expression patterns of ER, PR and LHR, could evidence for functionally glandular maldifferentiation in endometrosis. The cervical epithelial surface, stromal cells and smooth muscle cells were moderate to strongly staining for ER and PR, with little variation throughout the endometrial cycle but the immunorectivity was strongest during the anestrus in muscular and stromal cells. Surface epithelial cells of cervix were weak to moderate stained for LHR; smooth muscle cells showed weak staining for these receptors. There was no variation during cycle. In the oviduct, epithelial, stromal and muscle cells showed reactivity for RE and RP, during cycle and anestrus. Epithelial cells were moderate to strongly staining for these receptors, with evident irregularity in different types of cells. Apparently ciliated epithelial cells were stained but the intensity was much less than that observed in nonciliated epithelial cells, probably reflecting different functions of these cells. Stromal cells showed moderate staining during dioestrus and strongest reactivity in estrous and anestrus; muscle cells showed strong reactivity for ER throughout the cycle. The reactivity for LHR was weak to moderate throughout the cycle in the epithelial cells and weak in the muscle cells. During anestrus only three strains of muscle cells showed reactivity for LHR. In dioestrus the intensity was strongest. These findings evidence for the firs time the presence for LHR in extra-gonadal reproductive organs of mare. Though there were reports of ER and PR expression in equine endometrium, this is the first report of localization of these receptors in cervix and oviduct of mare using immunohistochemistry. It was found marked individual variation among the strains. These results probably were caused by the variation among the day of cycle and the complexity of mechanisms involved in the presence of these receptors. The findings of the present study allow us to infer that the ovarian steroid hormones nad LH function through their receptors in different tissues of mare reproductive tract, can help us to elaborate new strategies to improve the reproductive efficiency in this specie.
93

Avaliação morfofisiológica dos efeitos do bisfenol-A sobre o desenvolvimento neonatal da próstata de gerbilos (Meriones unguiculatus) / Morphophysiological evaluation of the effects of bisphenol A on the development of neonatal prostate gerbilis (Meriones unguiculatus)

Lima, Rodrigo Fernandes de 06 March 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-30T11:20:19Z No. of bitstreams: 2 Dissertação - Rodrigo Fernandes de Lima - 2015.pdf: 2077886 bytes, checksum: 41cc0e061b83ff79f5098eb054d1fcda (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-30T11:21:55Z (GMT) No. of bitstreams: 2 Dissertação - Rodrigo Fernandes de Lima - 2015.pdf: 2077886 bytes, checksum: 41cc0e061b83ff79f5098eb054d1fcda (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-30T11:21:55Z (GMT). No. of bitstreams: 2 Dissertação - Rodrigo Fernandes de Lima - 2015.pdf: 2077886 bytes, checksum: 41cc0e061b83ff79f5098eb054d1fcda (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-03-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The neonatal development is stimulated by various hormonal interactions. Environmental pollutants that mimic steroid hormones, such as bisphenol A (BPA) can cause changes in the pattern of development of the prostate, leading to lifelong lesions. The objective of this study was to determine whether neonatal exposure to BPA affects the development of prostate gerbils males and females. For this, the newborns were exposed to environmental levels (LBPA - 40 μ / kg / day) and high dose (HBPA - 4 mg / kg / day) of BPA, from 1st to the 7th day of life. On the eighth day, the prostatic complexes were collected and processed for morphological analysis, stereological and immunohistochemistry. It was observed through the three-dimensional reconstruction that in males the prostatic buds have elongated in a "V" form towards the ventral condensed mesenchyme (VMP). The stereological data of males showed a significant increase in the relative frequency of the mesenchymal compartment in the LBPA group compared to other groups (p ≤ 0.05). The AR-positive cells became significantly more frequent in the periurethral mesenchyme (PEM), ventral epithelial buds (VB) and muscle layer (SM) in the BPA group. There was a reduction in the frequency of PCNA-positive cells in the periurethral buds (PeB) and in the SM of the LBPA group. In females, the three-dimensional reconstruction showed that PeBs can emerge from one or both sides of the urethra and it was also visible a significant paraurethral mesenchyme (MAP) reduction in the BPA group. Only females of the HBPA group apparently presented paraurethral buds (PAB) more developed. In the LBPA group it was observed an increase in the AR-positive cells frequency in the PeM and a decrease of these cells in the PeB and mesenchyme paraurethral (PaM). In the HBPA group the AR-positive cells were more frequent in the PeM and PaB and reduced in PeB and PaM. PCNA-positive cells became significantly less frequent in the PaB and PaM of LBPA and HBPA groups. Regarding the ER-α positive cells in the group LBPA females showed a reduction in the immunoblots of PeM and MS, whereas in the group HBPA this reduction occurred only in the PaM. This study revealed that the postnatal development of the prostate of female gerbils occurs earlier and are morphologically distinct from what occurs in males of the same species. Furthermore, it can be seen that the BPA exerted a proliferative effect on the prostate gland of males and females with eight days of postnatal life, though females being more susceptible to this environmental chemicals. / O desenvolvimento neonatal é estimulado por diversas interações hormonais. Os poluentes ambientais que mimetizam hormônios esteróides, como o bisfenol-A (BPA), podem causar alterações no padrão de desenvolvimento da próstata, levando a lesões ao longo da vida. O objetivo deste estudo foi verificar se a exposição neonatal ao BPA afeta o desenvolvimento da próstata de gerbilos machos e fêmeas. Para isso, os recém-nascidos foram expostos a níveis ambientais (LBPA – 40 μ/kg/dia) e doses elevadas (HBPA – 4 mg/kg/dia) de BPA, do 1° ao 7º dia de vida. No oitavo dia, os complexos prostáticos foram coletados e processados para as análises morfológica, estereológica e imunohistoquímica. Com a reconstrução tridimensional observamos que nos machos os brotos prostáticos se alongaram em forma de “V” em direção ao mesênquima condensado ventral (VMP). Os dados estereológicos dos machos demonstraram um aumento significativo na frequência relativa do compartimento mesenquimal do grupo LBPA em relação aos demais grupos (p ≤ 0,05). As células AR-positivas tornaram-se significativamente mais frequentes no mesênquima periuretral (PeM), brotos epiteliais ventrais (VB) e camada muscular (SM) dos grupos tratados com BPA. Ocorreu uma redução na frequência de células PCNA-positivas nos brotos periuretrais (PeB) e na SM do grupo LBPA. Em fêmeas, a reconstrução tridimensional demonstrou que os PeBs podem emergir de um ou ambos os lados da uretra e também foi visível uma significativa redução do mesênquima parauretral (PaM) nos grupos tratados com BPA. Apenas as fêmeas do grupo HBPA apresentaram brotos parauretrais (PaB) aparentemente mais desenvolvidos. No grupo LBPA observou-se um aumento na frequência de células AR-positivas no PeM e uma diminuição destas células no PeB e mesênquima parauretral (PaM). No grupo HBPA as células AR-positivas tornaram-se mais frequentes no PeM e PaB, contudo sofreram redução no PeB e PaM. Células PCNA-positivas tornaram-se significativamente menos frequentes no PaB e PaM dos grupos LBPA e HBPA. Em relação às células ER-α positivas, nas fêmeas do grupo LBPA observou-se uma redução das imunomarcações no PeM e SM, enquanto que no grupo HBPA essa redução ocorreu apenas no PaM. Este estudo revelou que o desenvolvimento pós-natal da próstata de fêmeas de gerbilos é mais precoce e morfologicamente distinto do que ocorre nos machos da mesma espécie. Além disso, pode-se observar que o BPA exerceu um efeito antiproliferativo sobre a glândula prostática de machos e fêmeas com oito dias de vida pós-natal, sendo as fêmeas mais susceptíveis a este químico ambiental.
94

Growth and progression in colorectal cancer

Hörkkö, T. (Tuomo) 21 November 2006 (has links)
Abstract Colorectal cancer is the second most common malignancy in the Western World. The overall 5-year survival is still only 50–60%. Thus, better prognostic markers are needed to improve survival of the disease. Most colorectal cancers develop from pre-existing adenomas including conventional, flat and serrated adenomas. The most important prognostic factors include tumour stage, histologic subtype and poor differentiation. The prognosis of colorectal cancer depends mainly on tumour stage. The growth of colorectal cancer is determined by cell proliferation, differentation and apoptosis. The progression of colorectal cancer is associated with the growth pattern of colorectal cancer and its invasive margin. Cancer cell budding means the presence of cells scattered in the stroma at the invasive margin, and is associated with β-catenin, an adhesion protein involved in the nuclear Wnt/β-catenin pathway. Hormones may be directly involved in the growth of a cancer, for example sex hormones play an important role in the development of most gynaecological cancers. The knowledge about the dependency of cancers on other hormones, such as thyroid hormones, is limited. This thesis focuses on factors affecting growth and prognosis in colorectal cancer. Antibodies for Ki-67, caspase cleavage site for keratin 18, β-catenin and TRβ1 were used to determine their possible associations with colorectal cancer growth patterns and the characteristics of the invasive margin. Apoptosis and proliferation were decreased at the invasive margin, particularly in serrated adenocarcinomas. The invasive margin showed a presence of budding cell clusters in 24.0% of the cases and this predicted a very poor 5-year-survival (15.4%, P < 0.00001), but nuclear β-catenin accumulation did not predict budding. Thyroid hormone receptor TRβ1 was associated with polypoid growth, presence of KRAS mutations and also with a higher WHO histological grade and advanced Dukes' stage, and in in vitro analysis, thyroid hormone T3 had a modulatory effect on colorectal cancer cell protein synthesis and apoptosis. In conclusion, the growth type of colorectal cancer, i.e. conventional polypoid, flat or serrated, has an association with the characteristics of the invasive margin. Budding margin is associated with poor prognosis in colorectal cancer, and could be utilised in diagnostic pathology. Association of TRβ1 expression with polypoid growth pattern and the presence of KRAS mutations suggest that abnormalities in thyroid hormone signalling involving TRβ1 play a role in the development of some types of colorectal adenocarcinomas.
95

An investigation into the neuroprotective effects of estrogen and progesterone in a model of homocysteine-induced neurodegeration

Wu, Wing Man January 2006 (has links)
Homocysteine (Hcy) is a sulfur containing amino acid and is a potent neurotoxin. It has been shown that elevated levels of Hcy, termed hyperhomocysteinemia, plays a role in the pathologies of Alzheimer’s disease (AD) and age-related cognitive decline. Hcy is a glutamate agonist, which causes in increase in Ca[superscript (2+)] influx via the activation of NMDA class of excitatory amino acid receptors, which results in neuronal cell death and apoptosis. Estrogen and progesterone are female hormones that are responsible for reproduction and maternal behaviour. However, in the last decade, it is evident that both female hormones have neuroprotective properties in many animal models of neurodegeneration. Collectively, both estrogen and progesterone reduce the consequences of the oxidative stress by enhancing the antioxidant defence mechanisms, reducing excitotoxicity by altering glutamate receptor activity and reducing the damage caused by lipid peroxidation. However, the mechanisms by which estrogen and progesterone provide such neuroprotection probably depend on the type and concentration of hormone present. Moreover, numerous studies have shown that hormone replacement therapy (HRT, estrogen and progestins) or estrogen-only replacement therapy (ERT) may prevent or delay the onset of AD and improve cognition for women with AD. Clinical trials have also shown that women taking HRT may modify the effects of Hcy levels on cognitive functioning. Oxidative stress increases in the aging brain and thus has a powerful effect on enhanced susceptibility to neurodegenerative disease. The detection and measurement of lipid peroxidation and superoxide anion radicals in the brain tissue supports the involvement of free radical reactions in neurotoxicity and in neurodegenerative disorders. The hippocampus is an important region of the brain responsible for the formation of memory. However, agents that induce stress in this area have harmful effects and could lead to dementia. This study aims to investigate and clarify the neuroprotective effects of estrogen and progesterone, using Hcy-induced neurodegenerative models. The initial studies demonstrate that estrogen and progesterone have the ability to scavenge potent free radicals. Histological studies undertaken reveal that both estrogen and progesterone protect against Hcy-induced neuronal cell death. In addition, immunohistochemical investigations show that Hcy-induced apoptosis in the hippocampus can be inhibited by both estrogen and progesterone. However, estrogen also acts at the NMDA receptor as an agonist, while progesterone blocks at the NMDA receptor. These mechanisms reduce the ability of Hcy to cause damage to neurons, since Hcy-induced neurotoxicity is dependent on the overstimulation of the NMDA receptor. SOD and GPx are important enzymatic antioxidants which can react with ROS and neutralize them before these inflict damage in the brain. Hcy can increase oxidative stress by inhibiting expression and function of these antioxidants. However, it has been shown that the antioxidant abilities of both estrogen and progesterone can up-regulate the activities of SOD and GPx. These results provide further evidence that estrogen and progesterone act as antioxidants and are free radical scavengers. The discovery of neuroprotective agents is becoming important as accumulating evidence indicates the protective role of both estrogen and progesterone in Hcy-induced neurodegeneration. Thus further work in clinical trials is needed to examine whether reducing Hcy levels with HRT can become the treatment of neurodegenerative disorders, such as Alzheimer’s disease.
96

GnRH and neuropeptide regulation of gonadotropin secretion from cultured human pituitary cells

Wormald, Patricia J January 1988 (has links)
Gonadotropin-releasing hormone (GnRH) and its superactive analogues are currently being used in the treatment of a number of endocrine disorders, such as endometriosis, precocious puberty, infertility and prostatic cancer. Selection of these analogues for clinical use have been previously based on their activities in animal models. This thesis has therefore investigated the binding characteristics of the human GnRH receptor, in comparison to those of the rat receptor, as well as the activities of a number of GnRH analogues for stimulating luteinising hormone (LH) and follicle stimulating hormone (FSH) secretion from cultured human pituitary cells. The establishment of a human pituitary bioassay system has further made possible the investigation of the direct regulatory roles of GnRH and other neuropeptides in man. To date, such studies in man have been performed in vivo and are thus complicated by the simultaneous interactions of numerous modulators.
97

Estabilidade de genes de referÃncia e influÃncia das BMPs-6 e 7 sobre o desenvolvimento in vitro de folÃculos prÃ-antrais caprinos / Stability of reference genes and influence of BMP-6 and 7 on the in vitro development of caprine preantral follicles

Isana Mara AragÃo Frota 23 February 2010 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Este trabalho tem como objetivo avaliar a estabilidade de genes de referÃncia e a expressÃo de fatores de crescimento e de receptores de hormÃnios em folÃculos secundÃrios de caprinos. AlÃm disso, visa quantificar a expressÃo dos RNA mensageiros para BMP-6 e BMP-7 em folÃculos prÃ-antrais e antrais caprinos e avaliar os efeitos de FSH, BMP-6 e BMP-7 sobre o crescimento e expressÃo gÃnica em folÃculos secundÃrios caprinos durante 6 dias de cultivo. Para avaliar a estabilidade dos genes de referÃncia, folÃculos secundÃrios (150-200 Âm) foram isolados mecanicamente de ovÃrios caprinos. ApÃs a extraÃÃo do RNA total e sÃntese de DNA complementar, realizou a quantificaÃÃo dos mRNA, por PCR em tempo real, utilizando-se primers especÃficos para genes de referÃncia (GAPDH, β-tubulina, β-actina, PGK, UBQ, RPL-19, rRNA18S), fatores de crescimento (GDF-9, BMP-15, BMP-6, FGF-2, VEGF, KL e IGF-1) e receptores de hormÃnio (FSH-R, LH-R e GH-R). Para avaliar a expressÃo de BMP-6 e BMP-7, folÃculos primordiais, primÃrios e secundÃrios, bem como pequenos e grandes folÃculos antrais foram obtidos e os nÃveis de mRNA de BMP-6 e 7 foram quantificados. Nos estudos in vitro, os efeitos da BMP-6 (50 ng/mL) e BMP-7 (50 ng/mL) na presenÃa ou ausÃncia de FSH (50 ng/mL) sobre o desenvolvimento in vitro de folÃculos secundÃrios e sobre a expressÃo de mRNA para BMP-6 e 7 e FSH-R foi avaliada apÃs 6 dias de cultivo. Os resultados mostraram que UBQ e β-actina sÃo os genes de referÃncia mais estÃveis em folÃculos prÃ-antrais caprinos fresco cultivados por 12 dias. Os RNAs mensageiros para os fatores de crescimento (EGF, GDF-9, BMP-15, VEGF, FGF-2, BMP-6, IGF-1 e KL) e os receptores de FSH, LH e GH sÃo expressos em diferentes nÃveis em folÃculos prÃ-antrais de caprinos, sendo que o IGF-1 e o EGF apresentaram, respectivamente, o maior e o menor nÃvel de mRNA. O nÃvel de mRNA para BMP-6 em folÃculos primÃrios e secundÃrios foi significativamente maior do que aqueles em primordial, enquanto que os nÃveis de mRNA para BMP-7 foi maior nas cÃlulas da granulosa/teca de grandes do que nos pequenos folÃculos antrais. ApÃs o cultivo de folÃculos secundÃrios durante 6 dias, FSH aumentou o diÃmetro folicular e FSH e BMP-7 aumentou significativamente os nÃveis de mRNA para BMP-7 e FSH-R. Jà a BMP-6 na presenÃa ou ausÃncia de FSH aumentou o diÃmetro dos folÃculos secundÃrios. AlÃm disso, FSH aumentou os nÃveis de mRNA para BMP-6, enquanto ambos BMP-6 e FSH e aumentaram os nÃveis de mRNA para FSH-R, apÃs o perÃodo de cultivo. Em conclusÃo, UBQ e β-actina sÃo os dois genes mais estÃveis para folÃculos secundÃrios caprinos e o FSH e as BMPs dos tipos 6 e 7 estimulam o crescimento de folÃculos prÃ-antrais in vitro durante 6 dias de cultivo. / This study aims to evaluate the stability of reference genes and the expression of growth factors and hormone receptors in goat secondary follicles. It also seeks to quantify the expression of messenger RNA for BMP-6 and BMP-7 in goat preantral follicles and to evaluate the effects of FSH, BMP-6 and BMP-7 on growth and gene expression in secondary follicles goats after 6 days of culture. To evaluate the stability of reference genes, secondary follicles (150-200 μm) were mechanically isolated from goat ovaries. After extraction of total RNA and synthesis of complementary DNA, the quantification of mRNA was carried out by real-time PCR using specific primers for genes of reference (GAPDH, β-tubulin, β-actin, PGK, UBQ, RPL - 19, rRNA18S), growth factors (GDF-9, BMP-15, BMP-6, FGF-2, VEGF, KL and IGF-1) and hormone receptor (FSH-R, LH-R and GH-R). To evaluate expression of BMP-6 and BMP-7, primordial follicles, primary and secondary as well as small and large antral follicles were obtained and the mRNA levels of BMP-6 and 7 were measured. For in vitro studies, the effects of BMP-6 (50 ng / mL) and BMP-7 (50 ng / mL) in the presence or absence of FSH (50 ng / mL) on the development of secondary follicles and on the expression of mRNA for BMP-6 and 7 and FSH-R was evaluated after 6 days of culture. Results showed that mRNA for growth factors (EGF, GDF-9, BMP-15, VEGF, FGF-2, BMP-6, IGF-1 and KL) and the receptors for FSH, LH and GH are expressed in at different levels in preantral follicles of goats. Moreover, among the growth factors studied, IGF-1 and EGF had higher and lower levels or RNA, respectively. UBQ and β-actin genes were the mostr stable reference in fresh and cultured preantral follicles. The level of mRNA for BMP-6 in primary and secondary follicles was significantly higher than those in primordial follicles, while the levels of mRNA for BMP-7 was higher in granulosa cells / theca in large antral follicles than in small antral follicles. After culture of secondary follicles for 6 days, FSH increased follicular diameter and FSH and BMP-7 significantly increased the levels of mRNA for BMP- 7 and FSH-R. In addition, BMP-6 in the presence or absence of FSH increased the diameter of secondary follicles after 6 days of culture. Real-time PCR shoed that FSH increased the levels of mRNA for BMP-6, while both BMP-6 and FSH and increased levels of mRNA for FSH-R, after a period of 6 days of culture. In conclusion, UBQ and β-actin are the two most stable genes for secondary follicles goats and FSH and BMPs of types 6 and 7 stimulate the growth of preantral follicles after 6 days of in vitro culture.
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Engineering Cell-free Protein Synthesis Technology for Codon Reassignment, Biotherapeutics Production using Just-add-Water System, and Biosensing Endocrine Disrupting Compounds

Salehi, Sayed Mohammad 01 March 2017 (has links)
Cell-free protein synthesis is an emerging technology that has many applications. The open nature of this system makes it a compelling technology that can be manipulated to answer many needs that are unavailable in other systems. This dissertation reports on engineering this technology for: 1) sense codon emancipation for incorporation of multiple unnatural amino acids; 2) expressing a hard-to-express anticancer biotherapeutic and introducing a just-add-water system; 3) a biosensing ligand that interacts with nuclear hormone receptors. Emancipating sense codons toward a minimized genetic code is of significant interest to science and engineering. A promising approach to sense codon emancipation is the targeted in vitro removal of native tRNA. Here we introduce a new in-vitro or "cell-free" approach to emancipate sense codons via efficient and affordable degradation of endogenous tRNA using RNase-coated superparamagnetic beads. The presented method removes greater than 99% of tRNA in cell lysates, while preserving cell-free protein synthesis activity. The resulting tRNA-depleted lysate is compatible with in vitro-transcribed synthetic tRNA for the production of peptides and proteins. Biotherapeutics have many promising applications, such as anti-cancer treatments, immune suppression, and vaccines. However, due to their biological nature, some biotherapeutics can be challenging to rapidly express and screen for activity through traditional recombinant methods. In this work, we demonstrate the use of cell-free systems for the expression and direct screening of the difficult-to-express cytotoxic protein onconase. Using cell-free systems, onconase can be rapidly expressed in soluble, active form. Furthermore, the open nature of the reaction environment allows for direct and immediate downstream characterization without the need of purification. Also, we report the ability of a "just-add-water" lyophilized cell-fee system to produce onconase. Here we introduce a Rapid Adaptable Portable In-vitro Detection biosensor platform (RAPID) for detecting ligands that interact with nuclear hormone receptors (NHRs). The biosensor is based on an engineered, allosterically-activated fusion protein, which contains the ligand binding domain from a target NHR. The presented RAPID biosensor platform is significantly faster and less labor intensive than commonly available technologies, making it a promising tool for detecting environmental EDC contamination and screening potential NHR-targeted pharmaceuticals.
99

Prognosis in carcinoma in situ of the breast

Wärnberg, Fredrik January 2000 (has links)
<p>The incidence of breast cancer is rising steadily in Sweden and the proportion of carcinoma in situ (CIS) has increased appreciably, most likely due to mammography screening. The aim of this study was twofold: (1) to examine risk factors for subsequent invasive breast carcinoma and breast cancer death after primary ductal carcinoma in situ (DCIS) and (2) to study the biology in the progress between in situ and invasive carcinoma.</p><p> In a cohort-study based on 3,398 women with a primary CIS reported to the Swedish Cancer Registry (SCR) 1980-1992, women diagnosed in 1989-1992 ran a relative risk of 0.1 (CI 95%, 0.0-0.9) from dying of breast cancer as compared with women diagnosed in 1980-1982. Women in counties with mammography screening ran a relative risk of 0.2 (CI 95%, 0.0-2.1) for breast cancer death in comparison with women in non-screening counties.</p><p> In a case-control study derived from all 4,661 women with primary CIS reported to the SCR 1960-1992, we investigated risk factors for subsequent invasive breast carcinoma (n=118) and breast cancer death (n=39). Large size and multifocality were found to increase the risk for breast cancer death. Postoperative radiotherapy and mastectomy lowered the risk for ipsilateral invasive cancer.</p><p> The standardised incidence rates (SIR) for invasive breast cancer were estimated in the cohort from 1980-1992. The SIR after primary DCIS and primary lobular carcinoma in situ (LCIS) was 4.5 (CI 95%, 3.7-5.5) and 4.0 (CI 95%, 2.1-7.5), respectively.</p><p> New histopathological classification systems for DCIS were evaluated in 195 women consecutively diagnosed with primary DCIS between 1986-1994. One group with highly differentiated lesions was defined with the EORTC classification system and had an excellent prognosis.</p><p> Histopathological grade and expression of p53, c-erbB-2, Ki 67, hormone receptors, Bcl-2 and angiogenesis were compared in 626 women with either a pure DCIS, a small invasive carcinoma or a lesion with both an invasive and in situ component. When grade was taken into account, no change in tumour markers could be detected that signalled the progression from an in situ stage to invasiveness. All tumour markers correlated to grade and their distribution was very similar in the two components of mixed lesions.</p>
100

Core Biopsy of Breast and Axillary Lesions : Technical and Clinical Aspects

Abdsaleh, Shahin January 2006 (has links)
<p>The aims of this work were to image and analyze the needle behavior at automated core biopsy, to investigate the clinical utility of an alternative core biopsy technique using a semiautomated gun in breast and axillary lesions, and also to compare core biopsy with surgical specimens in malignant breast lesions regarding histologic features and hormone receptor expression.</p><p>In two experimental studies, using butter and silicon phantoms, respectively, the needle pass was imaged and its dynamic behavior studied. It was shown that the needle took a curved course in phantoms. It deviated to the same side as where the tip lay, and the degree of the curvature increased with increasing hardness of the phantoms. Our experimental methods can be applied for imaging of needle behavior and thereby improvement of needle configuration.</p><p>In two clinical studies, a semiautomated gun was used for large needle core biopsy of breast and axillary lesions in two series of 145 and 21 patients, respectively. The sensitivity of the method for diagnosis of malignancy was 87% (108/124), and in 37% (31/83) of cases the full length of the needle notch was filled with specimen. No injury to the neurovascular structures of the axillary area was observed. It was concluded that the semiautomated gun can be used as an alternative to the automated gun when the size and location of the lesion render use of the automatic device uncertain or dangerous, e.g., in small breast lesions or lesions located in the axilla.</p><p>In a series of 129 cases of breast cancer, comparison of core biopsy and surgical specimens showed that core biopsy provided enough information on the histologic type and grade of the lesions. Also, there was moderate to high concordance between the two methods for assessment of progesterone receptors and estrogen receptors (Spearman`s kappa 0.67 and 0.89, respectively).</p>

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