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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.
311

Investigação de componentes químicos da casca do caule de Luehea divaricata martius (malvaceae) e suas potenciais atividades biológicas / Investigation of chemical components from stem bark of Luehea divaricata martius (malvaceae) and its potential biological activities

Cunha, Sabrina Bassaldua da 24 June 2016 (has links)
Luehea divaricata, known as açoita-cavalo , is a Brazilian native species and has few reported in the literature. Phytochemical investigation of the methanolic crude extract and its fractions (acid ethereal, basic ethereal, basic ethyl acetate, neutral dichloromethane, neutral ethyl acetate and neutral hexane) from stem bark of L. divaricata (Malvaceae) resulted in the isolation of seven compounds: bis (2-ethyl-heptyl) ftalate (26), one triterpene friedelin (28), mixture of the terpenes α- (27) and β-amyrin (1), two steroids β-sitosterol (29) and glycosyl β-sisotsterol (14), and two flavonoids known as catechin (22) and epicatechin (8), which are diasteroisomers, respectively. The compound friedelin (28), isolated from ethereal acid fraction, was identified for first time in genus Luehea. The structures of the isolated metabolites were elucidated by 1H and 13C NMR in one- and two-dimensional analysis, by X-ray diffraction, melting point, beyond comparison with standard samples where possible and data available from literature. The extract, fractions and isolated compounds were tested for their antimicrobial activity and antioxidant capacity. Crude methanolic extract, fractions and isolated compounds from acid-base fractionation showed effective antibacterial (Gram-positive and Gram-negative) and antifungal activities for the strains tested. Basic and neutral ethyl acetate fractions showed good antioxidant potential when tested against their capacity. Thus, the study of phytochemical and pharmacological activities of the identified compounds from stem bark of L. divaricata expands knowledge alluding to chemotaxonomy and justifies its use in ethnopharmacology because, to date, only studies with other aerial parts were performed. / Luehea divaricata, conhecida como açoita-cavalo, é uma espécie nativa brasileira e com poucos relatos na literatura. A investigação fitoquímica do extrato bruto metanólico e de suas frações (etérea ácida, etérea básica, acetato de etila básica, diclorometano neutra, acetato de etila neutra e hexânica neutra) das cascas do caule de L. divaricata (Malvaceae) resultou no isolamento de sete compostos: Ftalato de bis (2-etil-heptila) (26), triterpeno friedelina (28), mistura triterpênica de α- (27) e β-amirina (1), dois esteroides β-sitosterol (29) e β-sisotsterol glicosilado (14), além de dois flavonoides conhecidos como Catequina (22) e epicatequina (8), estes sendo diasteroisômeros, respectivamente. O composto friedelina (28) isolado da fração etérea acida, foi identificado pela primeira vez no gênero Luehea. As estruturas dos metabólitos isolados foram elucidadas através de RMN 1H e 13C, uni e bidimensionais, por análise de difração de raio-X, ponto de fusão além de comparação com amostra padrão quando existente e dados disponíveis na literatura. O extrato, as frações e os compostos isolados foram testados quanto à sua atividade antimicrobiana e a sua capacidade antioxidante. Extrato bruto metanólico, suas frações e compostos isolados obtidos no fracionamento ácido-base apresentaram atividade antibacteriana (Gram-positivas e Gram-negativas) e antifúngica efetivas, para as cepas testadas. As frações acetato de etila básico e acetato de etila neutro quando testadas frente a sua capacidade antioxidante apresentaram um bom potencial. Dessa forma, o estudo fitoquímico e das atividades farmacológicas dos compostos identificados da casca do caule de L. divaricata amplia os conhecimentos alusivos à quimiotaxonomia, bem como justifica seu uso na etnofarmacologia pois, até o momento, apenas estudos com outras partes aéreas foram realizados.
312

Endocrine function and growth in young patients with childhood- or adolescence-onset epilepsy

Mikkonen, K. (Kirsi) 03 September 2004 (has links)
Abstract Endocrine disorders are common in adults with epilepsy on antiepileptic drugs (AEDs). This study aimed to evaluate endocrine function, lipid metabolism and growth in patients with childhood- or adolescence-onset epilepsy. Altogether 148 patients with epilepsy on carbamazepine (CBZ), oxcarbazepine (OXC), valproate (VPA) or lamotrigine monotherapy during pubertal maturation and 124 healthy controls participated in this population-based cohort study. Boys and young men (n = 140) underwent cross-sectional evaluation once, and girls and young women (n = 132) twice at an approximate interval of 6 years. Gonadal structure and serum reproductive and thyroid hormone and lipid concentrations were evaluated and growth data were gathered. Elevated serum testosterone and androstenedione levels and polycystic ovary syndrome (PCOS) were common in female subjects whose medication, especially VPA, continued into young adulthood. Serum reproductive hormone concentrations and ovarian structure were similar in patients off medication and controls in young adulthood. CBZ was associated with elevated serum sex hormone binding globulin and decreased dehydroepiandrosterone sulfate levels and VPA with elevated serum androstenedione concentrations in male patients. Testicular structure was similar in patients and controls. CBZ, OXC and VPA were associated with changes in serum thyroid hormone, thyrotropin and lipid levels during pubertal maturation in female patients, but these levels returned to normal after withdrawal of medication. Linear growth and final height were normal in female patients, but overweight was common if they had been obese and on VPA medication during pubertal maturation. Elevated serum androgen levels, PCOS and overweight are common if epilepsy and AED use, especially VPA, continue into young adulthood. These untoward changes or alterations in serum thyroid hormone or lipid concentrations are not present in young women with medication withdrawn. CBZ and VPA are associated with changes in serum sex hormone levels in boys and young men with epilepsy. Epilepsy and AED use during pubertal maturation does not seem to affect growth.
313

Evaluation of Systemic Steroid Dosing, Asthma-Related Readmissions, and Body Mass Index in Pediatric Patients with Asthma

Tharmarajah, Soba, Phan, Hanna, Haftmann, Richard January 2016 (has links)
Class of 2016 Abstract / Objectives: The purpose of this study was to evaluate whether overweight/obese children with asthma have different systemic steroid dosing practices and asthma related readmission rates compared to normal/underweight children with asthma. Methods: Medical charts of patients admitted between October 2013 and October 2014 for an acute asthma exacerbation were reviewed retrospectively. The primary objective was to compare the average weight based systemic steroid dose between overweight/obese (Group 1) and normal/underweight (Group 2) with asthma. The secondary objective was to compare asthma-related readmissions between both groups. Data collected included demographic data; 30 day, 90 day and 6-month asthma-related readmissions; asthma medications prior-to-admission, during hospitalization and upon discharge. Results: One hundred fifty nine admissions (147 patients with recorded BMI) were evaluated. There was no significant difference in the proportion of obese, overweight, healthy and underweight patients who had 6-month asthma readmissions (p > 0.05). The mean systemic steroid, including prednisone and methylprednisolone, weight based dosing was similar between Group 1 and Group 2 (p > 0.05). Likewise, the proportion of patients with 6-month readmissions was similar in both groups (p > 0.05). Conclusions: Acute asthma exacerbation pediatric patients whom are overweight/obese were not being dosed differently to normal/underweight patients and were not at risk for increased asthma-related readmission in the following 6 months.
314

The Effect of male-male competition and its Underlying Regulatory Mechanisms on the Electric Signal of the Gymnotiform fish <em>Brachyhypopomus gauderio</em>

Salazar, Vielka Lineth 30 October 2009 (has links)
Sexually-selected communication signals can be used by competing males to settle contests without incurring the costs of fighting. The ability to dynamically regulate the signal in a context-dependent manner can further minimize the costs of male aggressive interactions. Such is the case in the gymnotiform fish Brachyhypopomus gauderio, which, by coupling its electric organ discharge (EOD) waveform to endocrine systems with circadian, seasonal, and behavioral drivers, can regulate its signal to derive the greatest reproductive benefit. My dissertation research examined the functional role of the EOD plasticity observed in male B. gauderio and the physiological mechanisms that regulate the enhanced male EOD. To evaluate whether social competition drives the EOD changes observed during male-male interactions, I manipulated the number of males in breeding groups to create conditions that exemplified low and high competition and measured their EOD and steroid hormone levels. My results showed that social competition drives the enhancement of the EOD amplitude of male B. gauderio. In addition, changes in the EOD of males due to changes in their social environment were paralleled by changes in the levels of androgens and cortisol. I also examined the relationship between body size asymmetry, EOD waveform parameters, and aggressive physical behaviors during male-male interactions in B. gauderio, in order to understand more fully the role of EOD waveforms as reliable signals. While body size was the best determinant of dominance in male B. gauderio, EOD amplitude reliably predicted body condition, a composite of length and weight, for fish in good body condition. To further characterize the mechanisms underlying the relationship between male-male interactions and EOD plasticity, I identified the expression of the serotonin receptor 1A, a key player in the regulation of aggressive behavior, in the brains of B. gauderio. I also identified putative regulatory regions in this receptor in B. gauderio and other teleost fish, highlighting the presence of additional plasticity. In conclusion, male-male competition seems to be a strong selective driver in the evolution of the male EOD plasticity in B. gauderio via the regulatory control of steroid hormones and the serotonergic system.
315

Efficacy and Safety of Pharmacological and Non-Pharmacological Interventions in Juvenile Idiopathic Arthritis: A Series of Systematic Reviews and Network Meta-Analyses

Smith, Christine January 2017 (has links)
There is little head-to-head evidence comparing interventions available for juvenile idiopathic arthritis (JIA). This review involved a series of systematic reviews and network meta-analyses (NMAs) to evaluate the comparative efficacy and safety of pharmacological and non-pharmacological interventions among patients with JIA. Outcomes were the American College of Rheumatology Pediatric 30 (ACR Pedi 30) (disease response), its six composite outcomes, pain relief, health-related quality of life, and physical and emotional functioning. There was some evidence that etanercept had greater reduction in the number of joints with active arthritis compared to abatacept for polyarticular-course JIA and that canakinumab had improved ACR Pedi 30 over rilonacept. Non-pharmacological interventions showed no significant results for efficacy but were safe overall. Most included studies were low-quality and many were excluded from analysis because of unclear reporting or no results for outcomes of interest. As more studies are conducted this will improve the estimates from the NMAs.
316

Repercussões histopatologicas na prostata ventral do gerbilo da Mongolia (Merinones unguiculatus) apos suplementação por hormonios esteroides

Scarano, Wellerson Rodrigo 21 July 2006 (has links)
Orientador: Sebastião Roberto Taboga / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T17:58:14Z (GMT). No. of bitstreams: 1 Scarano_WellersonRodrigo_D.pdf: 4897591 bytes, checksum: ce5fe2f21b6836d646532424d518315c (MD5) Previous issue date: 2006 / Resumo: O tecido prostático é susceptível aos desníveis hormonais provocados, principalmente pelo processo de envelhecimento. A hiperplasia benigna prostática e o câncer de próstata são doenças que acometem uma grande parcela da população masculina, e parecem estar envolvidas com alterações hormonais. Por isso, o esclarecimento dos processos celulares e teciduais envolvendo os hormônios sexuais: testosterona e estradiol são, sem dúvida, importantes para o entendimento da etiologia desses processos patológicos. O gerbilo (Meriones unguiculatus) foi utilizado como modelo experimental pois, segundo a literatura, é susceptível ao aparecimento de lesões autóctones e responde bem à carcinogênese experimental, mostrando-se um bom modelo experimental. Numa primeira etapa, foram utilizados animais de três idades diferentes: púbere, adulta e senil. Esses animais foram submetidos à suplementação androgênica e as próstatas ventrais foram destinadas a análises histopatológicas, quantitativas, imunocitoquímicas e ultraestruturais. Foi observado aumento no peso da glândula e também na altura das células epiteliais em todas as idades. Tal aumento reflete o aumento da capacidade sintética observada pela dilatação das organelas de síntese, às vezes de aspecto vesiculoso, ocupando toda a região supranuclear. Nos animais adultos e velhos foram notadas regiões hiperplásicas e displásicas freqüentemente associadas a Neoplasias Intraepiteliais de diferentes graus e a adenocarcinomas. Houve aumento na espessura da camada de células musculares lisas (CML) ao redor dos ácinos nos animais púberes e adultos, enquanto nos animais velhos houve diminuição dessa camada. Além disso, as CML se mostraram aparentemente hipertróficas e com maior atividade sintética nos animais púberes e adultos. Foi notado aparente aumento da vascularização periacinar, onde se observou a presença de freqüentes vasos sanguíneos em todas as idades após o tratamento. Ademais, em todas as idades foi observado aumento da densidade de marcação de receptores androgênicos após o tratamento, evidenciando a possível relação desses receptores com os efeitos observados. Em uma segunda etapa experimental, avaliou-se o efeito do estradiol sobre o tecido prostático intacto e hipoandrogênico em animais adultos, tentando com isso simular situações de descompensação hormonal, típicas da senilidade. As alterações epiteliais foram freqüentes nos animais tratados com estradiol onde se observou aumento na altura das células epiteliais, aparecimento de regiões de intensa displasia e hiperplasia, e a formação de PINs. Outro aspecto que independe da presença da testosterona é o arranjo dos elementos fibrilares e não fibrilares da matriz extracelular entre as CML, apontando para um possível papel dessas células no rearranjo e na síntese desses componentes após os tratamentos estrogênicos. Nos animais castrados observou-se acúmulo de elementos da matriz extracelular sob o epitélio e em animais intactos presença desses elementos dispersos e escassos. Em ambos os grupos: intactos e castrados, notou-se que as CML e os fibroblastos apresentam fenótipo secretor acentuado após o tratamento com estradiol. Houve aumento na densidade de marcação ERa e AR positivos em regiões de hiperplasia apontando para um possível papel desses receptores na formação de lesões pré-malígnas e malignas. Portando, conclui-se que o gerbilo é susceptível a ação da testosterona e do estradiol, os quais provocam desarranjos estruturais e ultraestruturais de cunho patológico e funcional, mostrando-se um ótimo modelo para o estudo das doenças prostáticas de etiologia hormonal / Abstract: Not informed. / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
317

Senescência e próstata : interações dos hormônios esteroides e dos fatores de crescimento no microambiente glandular / Senescence and prostate : steroid hormone and growth factors interactions in the glandular microenvironment

Hetzl, Amanda Cia, 1984- 22 August 2018 (has links)
Orientador: Valeria Helena Alves Cagnon Quitete / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T09:05:18Z (GMT). No. of bitstreams: 1 Hetzl_AmandaCia_D.pdf: 39910159 bytes, checksum: 9f69d8623d48f1fccdc9aebc181573a3 (MD5) Previous issue date: 2013 / Resumo: A senescência é fator determinante para a ocorrência de alterações morfofuncionais da próstata. O objetivo desse estudo foi caracterizar e correlacionar as interações entre os receptores dos fatores de crescimento fibroblásticos (FGFR2, FGFR7, FGFR8), fator de crescimento epidermal (EGFR), ?-actina e vimentina e os receptores androgênicos (AR), estrogênicos ? e ? (ER?, ER?) e de prolactina (PR) nos compartimentos epiteliais e estromal frente à condição de senilidade e variações hormonais. Além disso, caracterizar e correlacionar o AR, ER?, ER? e PR com os FGFs nos compartimentos epitelial e estromal de amostras humanas com adenocarcinoma de alto grau e baixo grau. 50 ratos machos senis (10 meses de idade) e 10 ratos machos jovens (4 meses de idade) foram divididos em grupos: Jovem (JOV) e Senil (SE): óleo de amendoim por 30 dias; Castrado (CAS): castração cirúrgica e química; Tamoxifeno-Letrozol (TAM): tamoxifeno e de letrozol por 30 dias; Castrado+estrógeno (REEST): tratamento similar ao CAS, e posteriormente recebeu injeções de 17?-estradiol por 30 dias; Tamoxifeno-Letrozol+Andrógeno (RETEST): após tratamento similar ao grupo TAM, os animais receberam injeções de Cipionato de Testosterona por 30 dias. Os animais foram sacrificados e amostras do lobo ventral foram coletadas e submetidas às análises de Microscopia de Luz, imunohistoquímicas, western blotting e dosagem hormonal. 30 amostras prostáticas humanas foram divididas em grupos: Adenocarcinoma de alto grau e Adenocarcinoma de baixo grau. As amostras foram submetidas às análises de Microscopia de luz e imunohistoquímicas. Após a administração estrogênica, presença de microácinos, células inflamatórias e hipertrofia do estroma prostático foram observados. A hiperandrogenização levou à recuperação epitelial. No SE houve aumento de vimentina, ER? e PR em relação ao JOV. No CAS observou-se localização diferencial da prolactina e ?-actina em relação ao SE. No RETEST, observou-se recuperação do padrão de distribuição de reatividade da ?-actina e da prolactina em relação ao SE. No REEST foi observado aumento de ER? e ER? e localização diferencial destes, somando-se a diminuição da ?-actina e vimentina em relação ao SE. No TAM foi observada diminuição de ER? e ?-actina, e aumento de prolactina no compartimento estromal, em relação ao SE. Em humanos, os FGFR2 e FGFR8 apresentaram-se aumentados no estágio inicial do câncer prostático, sugerindo essas moléculas como bons alvos terapêuticos. Pode-se concluir que o envolvimento do ER? na ativação do estroma reativo tornou o microambiente favorável à progressão do câncer, devido à potencialização do desequilíbrio estromal, e o ER? contribuíram para a inibição das lesões précancerosas em homens na senescência. Já, o desequilíbrio causado pela ablação e/ou reposição hormonal não somente alterou o feedback entre os hormônios esteróides como modificou a localização da reatividade das moléculas nos compartimentos prostáticos, provavelmente interferindo nas sinalizações autócrinas e parácrinas dos estrógenos, EGF e prolactina, apontando esses como deflagradores da formação do estroma reativo. A ablação hormonal nos animais senis levou ao aumento da reatividade dos FGFs, sugerindo interações entre os hormônios e suas vias de sinalização e o microambiente prostático senil. As vias dos FGFs podem ser ativadas também de maneira andrógeno-independente, uma vez que os FGFs apresentaram níveis de detecção aumentados mesmo diante da intensa depleção androgênica imposta pela castração / Abstract: Senescence is a determining factor for morphological and functional prostatic alterations. The objective of this study was to characterize and correlate the interactions among fibroblast growth factor receptors (FGFR2, FGFR7, FGFR8), epidermal growth factor (EGFR), ?-actin and vimentin and the androgen receptor (AR), estrogen ? and ? (ER?, ER?) and prolactin (PR) in epithelial and stromal prostatic compartments in elderly rats on hormonal variation. Also, the objective was to characterize and correlate the AR, ER?, ER? and PR with the FGFs in the human prostatic samples, presenting high grade and low grade adenocarcinoma. Fifty male rats (10 months old) and 10 young male rats (4 months old) were divided into groups: Young (JOV) and Senile Groups (SE)- peanut oil injections for 30 days, Castrated Group (CAS)- surgical and chemical castration; Tamoxifen-Letrozole Group (TAM)- tamoxifen and letrozole injections in period of 48 hours for 30 days; Castrated + estrogen Group (REEST)- surgical and chemical castration and subsequently the animals received 17?-estradiol injections for 30 days; Tamoxifen- Letrozole + Androgen Group (RETEST): after treatment similar to the TAM group, the animals received testosterone cypionate injections for 30 days. After the treatment, the animals were sacrificed and the ventral lobe samples were collected and analyzed for the Light Microscopy, immunohistochemistry and Western blotting. Thirty human prostatic samples were collected from elderly men and divided into High-grade and Low-grade Adenocarcinoma Groups. The samples were submitted to light microscopy and immunohistochemical analyses. After estrogen administration, epithelial atrophy, microacini, inflammatory cells and stromal hypertrophy were observed. The hyperandrogenization led to the recovery of epithelium. The vimentin, ER? and PR increase was verified in the SE group in relation to JOV one. Differential localization of PR and ?-actin was seen in the CAS group in relation to SE one. Recovery of the distribution pattern of ?-actin and prolactin reactivities was observed in the RETEST group in relation to SE. In the REEST group, it was observed the ER? and ER? increase and differential localization of these receptors, and the ?-actin and vimentin decrease in relation to SE. In the group TAM, it was observed the ER? and ?-actin decrease and the prolactin increase in the stromal compartment in relation to SE group. Regarding to human samples, increased FGFR2 and FGFR8 were observed in the early stages of prostate cancer, suggesting these molecules as good therapeutic targets. Thus, it can be concluded that the involvement of ER? in activation of reactive stromal led to the favorable microenvironment to cancer progression considering the strong stromal imbalance, and the ER? contributed to the inhibition of precancerous lesions in elderly men. The imbalance caused by ablation and/or hormone therapy not only changed the feedback between steroid hormones but also changed the reactivity localization of molecules in prostatic compartments, probably interfering in the autocrine and paracrine signaling of estrogen, prolactin and EGF, and pointing these molecules as possible triggers of the formation of reactive stroma. The present results demonstrated that hormone ablation in senile rats led to increased reactivities of the FGFs, suggesting interactions among hormones and their signaling pathways and senile prostatic microenvironment. Furthermore, it can be concluded that the ways of FGFs can be activated also androgen-independent manner, considering that the FGFs showed increased levels in the severe androgen depletion characterized by castration / Doutorado / Anatomia / Doutora em Biologia Celular e Estrutural
318

Açao da dutasterida no tecido prostático humano normal : papel dos receptores hormonais esteroides como possíveis marcadores clínicos / Dutasteride action on the human normal prostate tissue : role of steroid hormonal receptors as possible clinical markers

Alonso, João Carlos Cardoso, 1972- 24 August 2018 (has links)
Orientadores: Wagner Eduardo Matheus, Ubirajara Ferreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T09:15:24Z (GMT). No. of bitstreams: 1 Alonso_JoaoCarlosCardoso_M.pdf: 3539592 bytes, checksum: 0be37d55627566f90e50845617162ed4 (MD5) Previous issue date: 2013 / Resumo: Introdução: Os andrógenos, além de desempenhar um papel importante no desenvolvimento e no crescimento da próstata, também são responsáveis pelo surgimento e progressão de lesões prostáticas. Portanto, as ações desses hormônios podem ser antagonizadas impedindo a conversão irreversível de testosterona em dihidrotestosterona, por meio da inibição da 5?-redutase. Neste contexto, os objetivos deste estudo foram caracterizar os efeitos clínicos e morfofuncionais da dutasterida, um inibidor de 5?-redutase, em receptores de hormônios esteroides no tecido da próstata humana normal, bem como para verificar a viabilidade desses receptores como potenciais marcadores para o manejo clínico dos pacientes em uso de dutasterida. Métodos: estudo prospectivo, duplo-cego e randomizado que avaliou 49 homens com idades entre 45 e 70 anos, sem alterações no exame de toque retal e com dosagens de PSA entre 2,5 e 4,0 ng/ml. Estes pacientes foram submetidos a biópsia de próstata guiada pelo ultrassom transretal, e após ter sido descartada neoplasia de próstata, foram divididos em dois grupos recebendo dutasterida (n=25) ou placebo (n=24). Os pacientes foram avaliados clinicamente a cada trimestre e, ao final de 12 meses, submetidos a novos testes laboratoriais e análise histopatológica por nova biópsia da próstata. Resultados: Os resultados não mostraram variações significativas nos níveis de estrógeno, testosterona séricos e índice de massa corporal em ambos os grupos, bem como de ER? (receptor estrogênico ?). No entanto, a imunorreatividade para AR (receptor androgênico) e ER? (receptor estrogênico ?) foram significativamente maiores no grupo dutasterida em relação ao grupo placebo, acompanhado por uma redução significativa do volume da próstata e dos níveis de PSA séricos no grupo dutasterida. Além disso, ambos os índices de proliferação e apoptose também foram significativamente maiores no grupo dutasterida, porém a razão proliferação/apoptose foi significativamente menor neste grupo, indicando assim predominância de apoptose. Conclusão: O tratamento com dutasterida mostrou distintas reatividades no tecido prostático normal, apontando a importância da ativação de ER? no mecanismo apoptótico, propiciando efeito protetor no tecido prostático normal, indicando ser este receptor um importante mediador para o seguimento clínico de pacientes em uso de dutasterida / Abstract: Introduction: The androgens, besides playing an important role in prostate development and growth, are also responsible for the development and progression of prostatic lesions. Therefore, preventing the irreversible conversion of testosterone into dihydrotestosterone by inhibiting 5?-redutase can antagonize the actions of these hormones. In this context, the aims of this study were to characterize the clinical and morphofunctional effects of 5?-redutase inhibitor, dutasteride, on steroid hormone receptors in the human normal prostate tissue, as well as to verify the viability of these receptors as potential markers to clinical management of patients on dutasteride use. Methods: Prospective, randomized and double-blind study, evaluating 49 men with ages between 45 and 70 years, no alterations in digital rectal examination and PSA levels between 2.5 and 4.0 ng/ml. These patients underwent prostate biopsy guided by transretal ultrasound (TRUS) with prostate neoplasia ruled out and it has divided into two groups receiving dutasteride (n=25) or placebo (n=24). Patients were clinically assessed every three months and at the end of 12 months undergoing new laboratory tests, prostate rebiopsy, histopathological and clinical analysis. Results: The results did not show significanty variations in serum estrogen and testosterone levels and body mass index in both dutasteride and placebo groups, as well as their ER? (? estrogen receptor). However, AR (androgen receptor) and ER? (? estrogen receptor) immunoreactivity were significantly higher in the dutasteride group in relation to placebo group, followed by a significant reduction in prostate volume performed by TRUS and total serum PSA levels in the dutasteride group when compared to placebo group. Furthermore, both proliferative and apoptotic indices were significantly higher in the dutasteride group in relation to placebo group. However, the proliferation/apoptotic ratio was significantly lower in the dutasteride group, indicating predominance of apoptotic process. Conclusion: The dutasteride treatment led to distinct reactivities in the normal prostate tissue, indicating different signals to the dynamics of the prostate and pointed out the importance of ER? pathways in the activation of apoptosis. Taken together, these data demonstrated that dutasteride treatment exerted protective effect in the normal prostate via ER?, indicating this receptor as important mediator to clinical management of patients on dutasteride use / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências
319

Quantitative proteomics of androgen receptor-mediated signaling networks in prostate tumor cells

Hsiao, Jordy Jame 01 May 2015 (has links)
Aberrant androgen receptor (AR) activity plays a critical role in the development and progression of both early-staged organ-confined and late-staged metastatic human prostate cancer. Recent large-scale genomic sequencing studies showed that ~50% of organ-confined prostate cancer patients have genetic rearrangements that placed the ETS transcription factors (e.g. ERG, ETV1) under the control of androgen-regulated gene promoters such as TMPRSS2. This results in the upregulation of the ETS transcription factors’ expressions in the presence of androgens. The aberrant overexpression of the ETS transcription factors are shown to induce the expression of genes that promote the cellular motility and invasive potential of prostate-tumor cells. Moreover, the improved therapeutic outcome of the second-generation anti-androgen therapies (e.g. abiraterone and enzalutamide) are encouraging, and prove that aberrant AR activity still drives the progression of metastatic prostate cancer. Although these treatments are initially effective, these cancer cells eventually develop resistance to these AR-targeted therapies termed castration-resistant prostate cancer (CRPC). Since the molecular steps involved in AR activation is still not clearly defined, it is critical to define the interactions required for AR activation prostate cancer cells, which will provide a framework for establishing more effective treatments to inhibit aberrant AR activity in human prostate cancer cells. Here, I developed a cellular system to isolate ligand-dependent interactions of AR in prostate-tumor cells. A siRNA luciferase screen was also developed and identified novel modulators of AR-mediated transcription selected from the proteomic dataset. Further biochemical studies showed that AR is associated with the Golgi membrane in a ligand-sensitive manner. And that the nuclear localization of ARA160, an AR coactivator, is regulated by the COPI retrograde trafficking machinery. Collectively, these results support the use of this cellular system to decipher the known AR-interacting proteins and novel components involved in AR signaling in prostate-tumor cells. I next investigated the androgen-sensitive AR transcriptional complexes and androgen-sensitive microsomes isolated from LNCaP prostate-tumor cells. Both studies yielded results that would further strengthen the diverse AR actions mediated within the cell. These results further support the notion that there is significant crosstalk amongst different cell surface receptor signaling pathways with AR. An extension of the androgen-sensitive microsome findings also led us to study the androgen-sensitive G-protein coupled receptor, CXCR7. I showed that androgens regulate the expressions of CXCR7 and CXCR4 and in turn modulated CXCL12-mediated motility in prostate tumor cells. Lastly, biochemical strategies were developed to detect differences in glycoprotein expression of frozen prostate cancer tissues isolated from human patients. I showed that the workflow successfully solubilized and isolated N- and O-linked glycoproteins from the frozen tissue samples and can be analyzed by quantitative mass spectrometry. This workflow would thus facilitate future biomarker studies. In summary, these data demonstrate the utility of developing methods for the comprehensive mapping of AR-mediated signaling in prostate cancer cells, and thus provide novel target candidates for the therapeutic treatment of metastatic or CRPC.
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Effects of Exogenous Steroids on the Adrenal Plasma Membrane Alteration of Steroidogenesis and Cell Morphology

Mattson, Mark Paul 08 1900 (has links)
Using cultured Y-1 mouse adrenal tumor cells which produce the steroid 20(-hydroxypregn-4-en-3-one (20-DHP), it was found that 10-5 M corticosterone and deoxycorticosterone increased basal and inhibited ACTH-induced 20-DHP production. The steroid effects were concentration-dependent, reversible, and specific since six other steroids did not stimulate steroidogenesis and varied in their ability to inhibit ACTH-induced steroidogenesis. Cytochalasin D inhibited steroid-stimulated 20-DHP production, suggesting a mechanism of steroid stimulation similar to that of ACTH. Steroidogenesis stimulated by cholera toxin, (Bu) 2 cAMP, or pregnenolone was not inhibited by exogenous steroid; corticosterone increased basal and inhibited ACTH-induced intracellular cAMP production. Steroids altered cell surface morphology. These findings suggest that steroids alter adrenal steroidogenesis by acting within the plasma membrane.

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