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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.
391

Desempenho dos Questionários Massachusetts Male Aging Study (MMAS) e Androgen Deficiency in the Aging Male (ADAM) na predição da testosterona livre em pacientes com 40 anos ou mais atendidos em ambulatório de urologia / Performance of Massachusetts Male Aging Sudy (MMAS) and Androgen Deficiency in the Aging Male (ADAM) questionnaires in the prediction of free testosterone in patients aged 40 years or older treated in outpatient regimen

Cabral, Renan Desimon January 2012 (has links)
Objetivo: Atualmente, a medição de Testosterona Livre calculada é considerado como sendo o padrão-ouro no diagnóstico do hipogonadismo em homens, porém, não está disponível para todos os indivíduos com suspeita de diminuição da função testicular. Portanto, avaliamos se o questionário Adrogen Deficiency in the Aging Male (ADAM) e o questionário Massachusetts Male Ageing Study (MMAS) poderiam ser utilizados como substitutos das determinações bioquímicas na identificação de hipogonadismo em homens com 40 anos ou mais. Métodos: Foram analisados 460 homens, com 40 anos ou mais de idade, participantes voluntários do programa de rastreamento de câncer de próstata do Hospital de Clínicas de Porto Alegre. Foi avaliada a capacidade dos questionários ADAM e MMAS de identificar homens com níveis baixos de Testosterona Total, Livre Calculara e Biodisponível. Resultados: A sensibilidade e especificidade do questionário ADAM, com relação à Testosterona Livre Calculada, foram de 73,6% e 31,9%, respectivamente. O uso de ADAM resultou em uma classificação adequada da nossa população em indivíduos normais ou hipogonádicos em 52,75% dos casos. Para o questionário MMAS, a sensibilidade foi calculada em 59,9% e a especificidade em 42,9%. Com o seu uso, a classificação dos pacientes foi realizada corretamente em 51,4% dos casos. Conclusão: Os questionários ADAM e MMAS têm uma sensibilidade adequada para identificar homens com baixos níveis de testosterona livre. No entanto, devido à sua falta de especificidade, estes testes não podem ser utilizados como um substitutos da dosagem de Testosterona Livre Calculada em homens com 40 anos ou mais em nosso meio. / Objective: At present, calculated free testosterone assessment is considered as the gold standard in diagnosing male hypogonadism. However, this assessment is not available for all individuals diagnosed with decreased testicular function. The investigators of this study were, thus, prompted to evaluate whether the androgen deficiency in the aging male (ADAM) and the Massachusetts Male Ageing Study (MMAS) questionnaires could be used to replace biochemical parameters in the diagnosis for hypogonadism in men aged 40 years and above. Methods: We evaluated 460 men, aged 40 years and above, all volunteers of a screening program for prostate cancer based at the Hospital de Clínicas of Porto Alegre. In this study, we assessed the efficiency of the ADAM and MMAS questionnaires in diagnosing Brazilian men with low levels of total, calculated free, and bioavailable testosterone. Results: The sensitivity of the ADAM questionnaire in diagnosing the calculated free testosterone was 73.6%, whereas specificity was 31.9%. ADAM could be used to properly classify our cohort into normal or hypogonadal individuals in 52.75% of the cases. The sensitivity of the MMAS questionnaire was 59.9%, whereas the specificity was 42.9%, resulting in a successful classification of 51.4% of the patients. Conclusion: The ADAM and MMAS questionnaires showed adequate sensitivity in diagnosing male patients with low levels of free testosterone. However, because of the lack of specificity, these tools cannot replace calculated free testosterone assessments in men aged 40 years and above.
392

Inibição da atividade das enzimas 5-alfa redutase e aromatase na prostata do gerbilo da Mongolia / 5-alpha reductase and aromatase enzymatic activies inhibition in the Mongolian gerbil prostate

Corradi, Lara Silvia 24 January 2008 (has links)
Orientador: Sebastião Roberto Taboga / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T18:00:13Z (GMT). No. of bitstreams: 1 Corradi_LaraSilvia_D.pdf: 6064748 bytes, checksum: 6595f8861a86f33fa6761af9a8f6b0a8 (MD5) Previous issue date: 2008 / Resumo: Os andrógenos têm papel central na biologia da próstata, mas os estrógenos também podem afetar o crescimento e a diferenciação desta glândula. Em tecidos específicos do corpo, a proporção entre andrógenos e estrógenos pode diferir significativamente daquela encontrada no plasma sanguíneo. As concentrações intracelulares desses esteróides nos tecidos alvos são reguladas pelo metabolismo local de hormônios, altamente dependente de enzimas específicas metabolizadoras de esteróides, como a 5a-redutase (5a-r) e a Aromatase (aro). Na próstata, a ação androgênica é acentuada devido à conversão de testosterona em dihidrotestosterona por ação da enzima 5a-r, enquanto que a aro é responsável pela aromatização da testosterona em estrógenos. Assim, a síntese local destes esteróides assume grande importância em doenças que acometem tecidos glandulares, como o câncer de próstata, onde níveis anormais de hormônios promovem o desenvolvimento e o aumento de ocorrência de malignidades. Desse modo, os papéis dos andrógenos e estrógenos ativados podem ainda ser melhor compreendidos na manutenção das interações homeostáticas epitélio-estromais prostáticas. Estudos com inibidores específicos destas enzimas vêm sendo desenvolvidos a fim de se tentar esclarecer os reais papéis enzimáticos na manutenção da fisiologia prostática, assim como no surgimento e desenvolvimento de doenças. De modo geral, após 30 dias consecutivos de inibição, simultânea ou não, das enzimas 5a-r e aro, respectivamente por ação da Finasterida e do Letrozol, a próstata de gerbilos jovens, adultos e velhos mostrou-se com o compartimento epitelial e o estromal alterados e reorganizados na tentativa de adaptar-se à nova condição hormonal induzida. Imediatamente após o término de administração das drogas, na fase inicial do período de pós-tratamentos, as concentrações de testosterona e estrógenos modificaram-se, as células epiteliais tiveram o padrão de atividade secretora alterada e, no estroma, a matriz extracelular ficou totalmente remodelada, além das células musculares lisas e dos fibroblastos fenotipicamente alterados. Na fase final do período de pós-tratamento, ficou evidente a tentativa da próstata em se normalizar morfologica e fisiologicamente, porém, em nenhuma das idades isso aconteceu de modo efetivo. O bloqueio da metabolização de hormônios esteróides na próstata pode ser uma ferramenta importante para o estudo da interação epitélio-estroma tanto na fisiologia normal, quanto nas doenças da próstata. Sugere-se portanto, que o desbalanço entre as concentrações de andrógenos e estrógenos provocados pela Finasterida e de Letrozol, juntos ou separados, alterou significativamente a interação epitélio-estroma. Todos os resultados obtidos parecem ser indicativos de importantes sinais do novo cenário hormonal intraprostático. A recuperação do equilíbrio entre as concentrações hormonais da próstata fica comprometida após o bloqueio enzimático, dando, portanto, às enzimas em estudo, status de crucial importância para o desenvolvimento e manutenção da próstata. O estabelecimento de modelos experimentais para o estudo das relações entre epitélio e estroma e o conhecimento dos componentes celulares e macromoleculares da próstata tornam-se instrumentos muito importantes para o entendimento do desenvolvimento, da estrutura e da fisiologia desta glândula / Abstract: Androgens have substantial role in the biology of the prostate, but estrogens also can affect the growth and differentiation of this gland. In specific tissues of the body, the ratio between androgens and estrogens can differ significantly from that found into plasma. The intracellular concentrations of these steroids in target tissues are mediated by a local hormone metabolism, by specifcs steroid-metabolizing enzymes, as the 5a-redutase (5a -r) and the aromatase (aro). In the prostate, the androgenic action is accented due to the conversion of testosterone in dihydrotestosterone by the activity of the 5a -r, while aro enzyme is an alternative pathway for the aromatization of testosterone into estrogens. These locally syntheses of steroids hormones assume thus, a great importance to the prostate cancer, where abnormal hormone levels can promote development and proliferation of malignancy to this gland. The activated functions of androgens and estrogens may be better understood focusing the maintenance of homeostatic prostatic epithelial-stromal interactions. Studies conducted with inhibitors of these specific enzymes have been carried out in an effort to clarify the real role of steroid-metabolizing enzymes in the maintenance of prostatic physiology, as well as into malignant progression prostatic cancer. After 30 consecutive days of inhibition, simultaneous or not, of the enzymes 5a -r and aro, respectively by Finasterida and Letrozol, the prostate of young, adult and old gerbils revealed that epithelial and estromal compartments were totally modified and reorganized in the attempt to adapt it to the new induced hormonal condition. Immediately after the end of drugs administration, in the early phase of the post-treatments period, the concentrations of testosterone and estrogens had been altered, the epithelial cells had their secretore activity pattern modified and, in the stromal compartment, the extracellular matrix was totally remodeled. The smooth muscle cells and fibroblasts became fenotipically modified. In the late phase of the post-treatments period, it was evident the attempt of the prostate gland in became morphologically and physiologically as a normal gland, however, this was not achieved in any analyzed gerbil. These steroids hormone metabolization blockade seems to be a good tool for the study of the epithelium-stroma interaction both in normal and abnormal prostate gland. Based on this data, it is suggested that the unbalance between androgens and estrogens intraprostatic concentrations provoked by Finasteride and Letrozol, together or not, interfered into the prostatic compartments interactions significantly. The results seem to be indicative of important signals of the new locally hormonal scene within the prostate gland. The recovery of balance hormonal concentrations of the prostate is damaged after the enzymatic blockade what gives, therefore, to this to 5a -r and aro enzymes, a status of crucial key for the normal and abnormal prostate gland. The establishment of experimental models for this kind of study and the knowledge of the cellular and macromolecular components of the prostate are also fundamental for the agreement of development, structure and physiology of prostate / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
393

Efeitos da somatotropina recombinante bovina sobre as características espermáticas, concentrações de testosterona e IGF1 no plasma seminal de touros (Bos taurus taurus) submetidos à degeneração testicular / Recombinant bovine somatotropin effects on testosterone and IGF1 levels of bulls (Bos taurus taurus) under testicular degeneration

Luiz Waldemar de Oliveira Souza 01 September 2004 (has links)
Dentre os diversos fatores que provocam diminuição no desempenho reprodutivo, a degeneração testicular térmica é o motivo mais freqüente de baixa fertilidade em Bos taurus no Brasil. Baseados nos efeitos sobre a secreção de hormônios hipofisários e gonadais, o GH vem sendo estudado para o tratamento da infertilidade masculina. Um delineamento experimental tipo blocos ao acaso utilizou dezesseis touros adultos submetidos a 4 tratamentos em esquema fatorial 2x2 (0 e 96 horas de insulação testicular, 0 e 1,2 mg bST/kg PV), com o objetivo de testar os efeitos da bST no tratamento de touros submetidos a insulação testicular. Motilidade, alterações de acrossoma, defeitos de cauda e cabeça, gota protoplasmática proximal e defeitos espermáticos totais aumentaram em conseqüência da insulação testicular. As concentrações seminais de Testosterona foram temporariamente diminuídas em resposta a insulação testicular. A ocorrência de gota protoplasmática distal, anomalias de peça intermediária e concentrações seminais de IGF1 não foram afetadas pela insulação testicular. A somatotropina recombinante bovina não afetou as características espermáticas ou concentrações seminais de Testosterona e IGF1. / Testicular heat degeneration is the most common cause of poor fertility of Bos taurus bulls in the tropics. The Growth Hormone has been studied in man infertility treatment with some progress. A randomly blocks experimental design used 16 mature bulls allotted in 4 treatments in a 2x2 factorial arrangement (0 e 96 hours of scrotal insulation, 0 e 1,2 mg bST/kg BW) was performed to asses the effects ob bulls submitted to scrotal insulation. Motility, abnormal acrosome, tail and head defects, proximal droplet, and abnormal sperm increased, and seminal plasma Testosterone was temporally increased in response to scrotal insulation. Distal droplet, midpiece and seminal plasma IGF1 were not affected by bST. The bST did not affect sperm characteristics or seminal Testosterone and IGF1.
394

Avaliação ecocardiográfica do índice de massa ventricular esquerda em crianças com hipospádia após estimulação hormonal com testosterona tópica - um ensaio clínico controlado randomizado / Echocardiographic evaluation of left ventricular mass index in children with hypospadias after hormonal stimulation with topical testosterone: a randomized controlled trial

Andrade, Elisabeth Campos de 31 July 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-09-20T13:55:36Z No. of bitstreams: 1 elisabethcamposdeandrade.pdf: 10436022 bytes, checksum: ee61c000d375df1c659ffc7041f3103f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-09-22T15:12:59Z (GMT) No. of bitstreams: 1 elisabethcamposdeandrade.pdf: 10436022 bytes, checksum: ee61c000d375df1c659ffc7041f3103f (MD5) / Made available in DSpace on 2017-09-22T15:12:59Z (GMT). No. of bitstreams: 1 elisabethcamposdeandrade.pdf: 10436022 bytes, checksum: ee61c000d375df1c659ffc7041f3103f (MD5) Previous issue date: 2017-07-31 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A testosterona é frequentemente utilizada no período pré-operatório da cirurgia nos casos de hipospádia grave. Estudos anteriores demonstraram a presença de receptores androgênicos em miócitos cardíacos que podem modular o fenótipo. O uso de doses suprafisiológicas de andrógenos pode levar à toxicidade no músculo cardíaco e, em alguns casos, à hipertrofia ventricular esquerda. Este ensaio clínico randomizado duplo-cego controlado visa avaliar o efeito do uso de testosterona tópica sobre o pênis no índice de massa ventricular esquerda em meninos com hipospádia. Foram incluídos meninos com hipospádia de 6 meses a 9 anos. Os meninos foram divididos em dois grupos: G1 - meninos que receberam creme de propionato de testosterona 1%, duas vezes ao dia, durante 30 dias e G2 - meninos que receberam creme placebo na mesma posologia. Todos os meninos foram submetidos à avaliação ecocardiográfica bidimensional para medir o índice de massa ventricular esquerda e a exame físico para avaliação da pressão arterial e do índice de massa corporal antes do tratamento, ao seu término e 60 dias após. Foram determinados os níveis de testosterona sérica, LH e FSH. Trinta e cinco meninos foram analisados, sendo 17 no G1 e 18 no G2. Não foram encontradas diferenças no índice de massa do ventrículo esquerdo (massa ventricular esquerda indexada pela área de superfície corporal) antes do tratamento. O índice de massa do ventrículo esquerdo foi de 59,21 ± 11,91 g/m² em G1 e 55,12 ± 8,29 g/m² em G2 (p=0,244) ao final do tratamento e 61,13 ± 11,69 g/m² em G1 e 62,84 ± 35,99 g/m² em G2 (p=0,852) 60 dias após. Os níveis séricos de testosterona foram 12 [7-80] ng/dL em G1 e 5 [5-7] ng/dL em G2 (p=0,018) ao final do tratamento e 10 [5-11] ng/dL em G1 e 5 (4-5) ng/dL em G2 (p=0,155), 60 dias após. Houve um pequeno aumento na pressão arterial sistólica (PAS) ao final do tratamento (83,82 ± 7,18 mmHg) no grupo que recebeu testosterona (G1) comparado com o grupo que recebeu placebo (G2), 77,5 ± 6,69 mmHg (p=0,010). Após 60 dias, os níveis de PAS retornaram aos níveis basais em G1 (82,35 ± 5,62 mmHg) e em G2 (81,38 ± 4,79 mmHg) (p=0,588). A testosterona tópica pode ser considerada segura no período pré-operatório de meninos com hipospádias sem risco de hipertrofia ventricular esquerda. Houve um aumento dos níveis de PAS durante o uso da testosterona, que foi transitório, retornando a níveis normais 60 dias após a suspensão da droga. / Testosterone is often used in the preoperative period of surgery in cases of severe hypospadias. Previous studies have demonstrated the presence of androgen receptors in cardiac myocytes that can modulate the phenotype. The use of supraphysiological doses of androgens can lead to toxicity on the heart muscle and, in some cases, to left ventricular hypertrophy. This randomized double blind controlled clinical trial aims to evaluate the effect of topical testosterone on left ventricular mass index in boys with hypospadias. Boys with hypospadias aged 6 months to 9 years were included. Boys were divided into two groups: G1 - boys who received testosterone propionate 1% ointment twice a day for 30 days, and G2 - boys receiving placebo ointment in the same regimen. All boys were submitted to bidimensional echocardiographic evaluation to compare the left ventricular mass index, blood pressure, and body mass index before treatment, at its ending and 60 days later. Levels of serum testosterone, LH, and FSH were measured. Thirty-five boys were analyzed: 17 in G1 and 18 in G2. No differences were found in left ventricular mass index (left ventricular mass indexed by body surface area) prior to treatment. Left ventricular mass index was 59.21 ± 11.91 g/m² in G1 and 55.12 ± 8.29 g/m² in G2 (p=0.244) at the end of the treatment and 61.13 ± 11.69 g/m² in G1 and 62.84 ± 35.99 g/m² in G2 (p=0.852) 60 days later. Serum testosterone levels were 12[7-80] ng/dL in G1 and 5[5-7] ng/dL in G2 (p=0.018) at the end of the treatment of treatment and 10[5- 11] ng/dL in G1 and 5[4-5] ng/dL in G2 (p=0.155), 60 days later. There was a small increase in systolic blood pressure (SBP) at the end of the treatment (83.82 ± 7.18 mmHg) in the group who receive testosterone (G1) compared with controls (G2), 77.5 ± 6.69 mmHg (p=0.010). Passing 60 days, SBP levels returned to basal levels in G1 (82.35 ± 5.62 mmHg) and in G2 (81.38 ± 4.79 mmHg) (p=0.588). Topical testosterone can be considered safe in the preoperative period of boys with hypospadias with no risk of left ventricular hypertrophy. An increase in systolic blood pressure occurs while using testosterone but it is transitory, returning to normal levels 60 days after the discontinuation of the drug.
395

The implementation of in vitro assays to screen environmental samples for male reproductive toxicity

Ebrahim, Mozaffar January 2010 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Endocrine disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints.The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH)  concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T.violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250,2500 and 5000 μg/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25 & mu;M) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity. / South Africa
396

EFEITOS DA OXIMA BUTANO-2,3-DIONATIOSSEMICARBAZONA FRENTE AO DANO TESTICULAR CAUSADO POR CÁDMIO EM CAMUNDONGOS / EFFECTS OF BUTANE-2,3-DIONE THIOSEMICARBAZONE OXIME ON TESTICULAR DAMAGE INDUCED BY CADMIUM IN MICE

Freitas, Mayara Lutchemeyer de 06 March 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / We investigated the action of butane-2,3-dione thiosemicarbazone oxime against the testicular damage caused by cadmium chloride (CdCl2) in mice swiss adult male. The animals received a single injection of CdCl2 at the dose of 5 mg/kg, intraperitoneally, and after thirty minutes, the oxime was administered subcutaneously at the dose of 10 mg/kg. Twenty four hours after administration of the oxime, the animals were euthanized the blood were collected and after killed the testes were removed for analysis. The parameters determined were δ-aminolevulinate dehydratase (δ-ALA-D), myeloperoxidase (MPO), glutathione-S-transferase (GST) and glutathione peroxidase (GPx) activities, in testicular tissue. The levels of thiobarbituric acid-reactive substances (TBARS), nonprotein thiols (NPSH), ascorbic acid and the quantity of cadmium in testes were also evaluated. In addition, levels of testosterone in serum and cytokines (proinflammatory, IL-1, IL-6, TNF-α, IFN-γ and anti-inflammatory IL-10) were determined. Histological analysis of testicular tissue was also performed. Our results demonstrated that the oxime was effective in restoring partially the inhibition in δ-ALA-D activity induced by CdCl2. The activation of MPO and increase in IL-1, IL-6, TNF-α and IFN-γ levels induced by CdCl2 were also reduced by oxime. IL-10, which was reduced by cadmium, was partially restored by oxime administration. In addition, the oxime was effective in restoring the increase in TBARS levels and partially the reduction on NPSH levels induced by CdCl2. However, the oxime did not have action on the decreased levels of ascorbic acid induced by CdCl2 or on the decrease in enzymatic activity of GST and the increased enzymatic activity of GPx caused by CdCl2. Our results demonstrated that oxime was effective in restoring the histological alterations induced by CdCl2, preventing the loss of elongated spermatids. In addition, oxime was able to increase the testosterone levels reduced by cadmium exposure. In conclusion, the oxime tested was effective in reducing the testicular damage induced by CdCl2 in mice. The beneficial effects of this oxime are related to its antioxidant and anti-inflammatory action. / Investigamos a ação da oxima butano-2,3-dionatiossemicarbazona contra o dano testicular causado por cloreto de cádmio (CdCl2) em camundongos swiss adultos machos. Os animais receberam uma única injeção de CdCl2 na dose de 5mg/kg, intraperitonialmente e, após trinta minutos, foi administrada a oxima subcutâneamente na dose de 10 mg/kg. Vinte quarto horas após a administração da oxima, os animais foram anestesiados o sangue foi coletado, após a eutanásia tiveram os testículos removidos para as análises. Os parâmetros determinados foram as atividades das enzimas δ-aminolevulinato desidratase (δ-ALA-D), mieloperoxidase (MPO), glutationa-S-transferase (GST) e glutationa peroxidase (GPx), no tecido testicular. Os níveis de substâncias reativas ao ácido tiobarbitúrico (TBARS), tióis não protéicos (NPSH), ácido ascórbico e quantidade presente de cádmio nos testículos também foram avaliados. Além dos níveis de testosterona no soro, onde também se quantificou as citocinas (pró-inflamatórias IL-1, IL-6, TNF-α, IFN-γ e anti-inflamatória, IL-10). Também foi realizada a análise histológica de tecido testicular. Nossos resultados demonstraram que a oxima foi efetiva em restaurar parcialmente a inibição da atividade da enzima δ-ALA-D induzida por CdCl2. A ativação da MPO e o aumento dos níveis de IL-1, IL-6, TNF-α e IFN-γ induzidos por CdCl2 também foram reduzidos pela oxima. A IL-10, que foi reduzida pelo cádmio, teve seus níveis restaurados parcialmente pela oxima. Além disso, a oxima foi efetiva em restaurar o aumento nos níveis de TBARS e parcialmente a redução nos níveis de NPSH induzidos pelo CdCl2. Porém, não teve ação sobre a queda dos níveis de ácido ascórbico provocado pelo CdCl2, nem sobre a diminuição da atividade enzimática da GST e sobre o aumento da atividade enzimática da GPx causados pelo CdCl2. Nossos resultados demonstraram que a oxima foi efetiva em conter as alterações histológicas causadas pelo CdCl2, prevenindo a perda de espermátides alongadas. A oxima também foi capaz de aumentar os níveis de testosterona reduzidos pela exposição ao cádmio. Em conclusão, a oxima testada foi efetiva em reduzir os danos testiculares induzidos pelo CdCl2. Os efeitos benéficos desta oxima estão relacionados às suas propriedades antioxidantes e sua ação anti-inflamatória.
397

Effect of Eurycoma longifolia (Tongkat Ali) on the prostate cancer cell line LNCaP

Abouhamraa, Hamza January 2013 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Eurycoma Longfolia Jack, also known as Tongkat Ali (TA) is a tropical plant belonging to the family of Simaroubaceae is widely distributed in South East Asian countries. The extracts of TA have been proven to have cytotoxicity, anti-proliferative and aphrodisiac properties. In vitro assays revealed cytotoxicity toward human breast cancer cell lines MCF-7, KB, CaOV-3, RD, DU-145and HepG2 human liver cancer cells and appear promising as a new chemotherapeutic agent against human cervical carcinoma (HeLa) cells. Although, there are extensive studies reported on its cytotoxicity benefits there are none pertaining to LNCaP human prostate cell line. Therefore, this study aimed at testing the effects of TA on LNCaP cells and prostate specific antigen (PSA) production. Materials and Methods This study investigated the effect of different concentrations of TA (0.0025, 0.025, 2.5, 25 and 250 g/ml) TA on LNCaP human prostate cancer cell line for 24 and 96 hours. The following parameters were investigated: morphology, cell viability (MTT), testosterone modulation, Annexin V-CY3 binding (Apoptosis), DNA fragmentation (TUNEL), caspase 3/7 activity (apoptosis), and PSA production. Results When observing the morphological changes of LNCaP cells exposed to TA, a clear increase in detachment and cell death via apoptosis as the concentrations of TA increased. The viability decreased significantly in both 24 and 96 hour treatment of TA at higher dosages (25 and 250 g/ml). The significant inhibitory effects on testosterone stimulated cell proliferation were seen at TA concentrations as low as 0.0025 μg/ml TA. At higher concentrations of TA (25 and 250 μg/ml), for all testosterone dosages a decreasing trend in proliferation was found. vii Testosterone concentrations of 10 nM showed maximum stimulation of cell proliferation for TA dosages up to 2.5 μg/ml. All concentrations of TA showed significant increase in apoptosis of the cells as dosages increased. A higher amount of DNA damage found at the highest dosage (250 μg/ml) of TA. The relative caspase 3/7 activation showed significant (P=0.0043) activation at the highest concentration (250 μg/ml) of TA. Relative PSA production resulted only a 5% increase with no significant difference at all doses indicting that TA does not change the cell PSA production and the decline in PSA concentration is due to LNCaP cells dying as a result of this exposure to TA. Conclusion In summary, the major finding of this study is that Tongkat Ali inhibits the viability of prostate cancer cell lines (LNCaP) through caspase-mediated pathway, as well as increased the level of apoptotic such as DNA fragmentation. In addition, Tongkat Alin also inhibited PSA production. In LNCaP cells, testosterone with the addition of TA does not increase the growth of the cells. However, more in-vitro and in-vivo studies are needed to establish the exact constituents of the extracts and their mechanism of action. Thus, this study opens perspectives on the use of Tongkat Ali preparations in the treatment of aging male symptoms, prostate cancer prevention or as additional treatment to standard prostate cancer therapy.
398

La testostérone, médiateur de l'honnêteté des signaux sexuels chez le mâle Hyla arborea? / Is testosterone the mediator of sexual signal honesty in Hyla arborea?

Desprat, Julia L. 18 December 2015 (has links)
Chez les mâles, la testostérone joue un rôle important dans l'expression des signaux sexuels attractifs pour la femelle. Cependant, de nombreuses études mettent en évidence l'effet négatif de la testostérone sur les défenses immunitaires ou la résistance aux parasites. Selon l'hypothèse du handicap immunitaire (ICHH, Folstad et Karter, 1992), ce compromis permettrait d'assurer l'honnêteté du signal sexuel ; les mauvais mâles ne pouvant pas exprimer de signaux sexuels de bonne qualité tout en gérant l'immunosuppression due à la testostérone. Ma thèse a pour objectif de définir le rôle de la testostérone dans l'honnêteté des signaux sexuels dans un contexte de communication multimodale. Elle permet également de comprendre les mécanismes physiologiques par lesquels la testostérone module les signaux sexuels acoustiques et visuels chez les mâles Hyla arborea, un amphibien connu pour utiliser ces deux types de signaux pour attirer les femelles. Nos résultats montrent que les signaux sexuels acoustiques et visuels chez cette espèce sont testostéronedépendants. En revanche, puisque la testostérone n'a pas d'effet immunosuppresseur dans notre étude, elle ne serait pas le médiateur direct de l'honnêteté des signaux chez cette espèce. D'un point de vue physiologique, l'effet de la testostérone sur le chant s'explique par l'amélioration des propriétés contractiles des muscles du tronc responsables du chant lié à une augmentation de l'efficacité mitochondriale. D'autre part, les analyses biochimiques montrent que la couleur du sac vocal varie linéairement avec la quantité de pigments caroténoïdes présents dans le plasma, qui pourrait être testostérone-dépendant. Enfin, cette thèse montre également que la testostérone agit sur le comportement de chasse permettant l'acquisition de ressources énergétiques et de caroténoïdes pour le chant et la couleur des mâles / In males, testosterone plays an important role on attractive sexual signal expression. However, numerous studies highlighted that testosterone also has negative effects on immunity defenses and parasite resistance capacity. According to the immunocompetence handicap hypothesis (ICHH, Folstad and Karter, 1 992), this trade-off assures signal honesty because only good males could express powerful signals while managing the immunosuppression of testosterone. My thesis aims to define the role of testosterone on the signal honesty in a multimodal communication context. Moreover it allows us to understand some physiological mechanisms involved in the modulation of acoustic and visual signals in males Hyla arborea, an amphibian known to use both acoustic and visual signals to attract females. Our results show that acoustic and visual signals are testosterone-dependent. In contrast, since testosterone has no immunosuppression effect in our study, it would not be the direct mediator of the signal honesty in this species. From a physiological point of view, the testosterone effects on calls could be explained through the positive effect of testosterone on trunk muscle mitochondrial efficacy and their contractile properties. Besides, biochemical analyses show that vocal sac coloration varies with the amount of carotenoid pigments present in the plasma that could be testosterone-dependent. Finally, this thesis also assumes that testosterone acts on the hunting behavior permitting the acquisition of energy resources and carotenoids for singing and coloration of males
399

Alterações motoras e imunohistoquímica da administração crônica de propionato de testosterona em ratos, de ambos os sexos, submetidos ao modelo de parkinsonismo induzido por reserpina / Motor and immunohistochemistry changes of chronic testosterone propionate administration in both gender of rats, submitted to parkinsonism model induced by reserpine

Bispo, José Marcos Meneses 11 August 2016 (has links)
Fundação de Apoio a Pesquisa e à Inovação Tecnológica do Estado de Sergipe - FAPITEC/SE / Parkinson's disease (PD) shows sex differences in susceptibility, pathogenesis and clinical condition. The most common incidence in males suggests sex hormones as a potential contributing factor to the individual susceptibility to this disease. Thus, the purpose of this study was evaluate the effect of chronic testosterone propionate (TP) administration on the motor and neurochemical changes in Parkinsonism model induced by reserpine (RES);and to compare the effects of administration of low doses of RES between males and females (intact and ovariectomized). A hundred ninety-two 6-9-month-old males and females Wistar rats were used. Animals were obtained from vivarium of the Department of Physiology - Federal University of Sergipe. The study was divided into three experiments: (I) testosterone propionate administration in intact male rats, (II) in intact female rats and (III) in ovariectomized rats. In all experiments, the rats were divided into eight groups: 1) testosterone propionate vehicle (CTRt) + reserpine vehicle (CTR); 2) 0.1mg / kg of TP (0.1TP) + CTR; 3) 1.0 mg / kg of TP (1.0TP) + CTR; 4) 5.0mg / kg of TP (5.0PT) + CTR; 5) CTRt + RES; 6) 0.1TP +RES; 7) 1.0TP+ RES and 8) 5.0TP + RES. Animals received 31 injections of testosterone propionate or vegetable oil (i.m.) daily and 15 injections of 0.1 mg / kg RES or vehicle (s.c.) every other day. During the treatment, the animals were weighed every four days and submitted to the following behavioral procedures: catalepsy (daily) and open field (day 31). On day 31, the rats were anesthetized, perfused and their brains were removed and subjected to the immunohistochemistry technique for tyrosine hydroxylase (TH). We show that the RES administration generates a sex-dependent response in the behavior of catalepsy and number of TH+ cells in the Ventral tegmental area (VTA). Regarding the co-administration of PT and RES in the catalepsy test, the treatment with TP showed reduced motor effects in males (Exp. I) in 5.0PT+RES group, while in females (Exp. II and III) this effect was observed at the dose of 1.0 mg / kg (1.0PT+RES) and 5.0 mg / kg (5.0PT+RES). In the open field, none of the doses of TP, in any of the experiments, was able to minimize the effects caused by the RES in motor activity. In intact males (Exp. I), all tested doses of TP were able to prevent the reduction of TH+cells caused by the RES in VTA, but not in Substantia nigra pars compacta. In intact females (Exp. II), only the dose of 5.0 mg / kg (5.0PT+RES) was able to prevent the reduction of TH+ cells in the SNpc. In ovariectomized females (Exp. III) the treatment with all doses of TP (0.1PT+RES, 1.0PT+RES and 5.0PT+RES) was able to maintain the intensity of TH in the dorsal striatum, preventing reduction caused by the RES. Taken together our results show that Chronic treatment with TP, in progressive model of parkinsonism induced by RES, showed different effects in behavioral tests and animals of different sex and conditions, showing multiple possible mechanisms of action. / A doença de Parkinson (DP) exibe diferenças sexuais na suscetibilidade, patogênese e quadro clinico, sendo a incidência mais comum no sexo masculino, evidenciando os hormônios sexuais como potencial fator que contribui para predisposição do indivíduo a esta doença. Diante disso, o objetivo do presente trabalho foi avaliar a ação da administração crônica de propionato de testosterona (PT) sobre as alterações motoras e neuroquímicas no modelo de parkinsonismo induzido por reserpina (RES); além de comparar os efeitos da administração de baixas doses de RES entre machos e fêmeas (intactas e ovariectomizadas). Foram utilizados 192 ratos Wistar de ambos os sexos, 6-9 meses, provenientes do Biotério Setorial do Departamento de Fisiologia da Universidade Federal de Sergipe. O estudo foi dividido em 3 experimentos: (I) administração de propionato de testosterona em ratos intactos, (II) em ratas intactas e (III) em ratas ovariectomizadas. Os ratos foram divididos em oito grupos: 1- veículo proprionato de testosterona (CTRt)+veículo RES (CTR); 2- 0,1mg/kg de PT (0,1PT)+CTR; 3- 1,0 mg/kg de PT (1,0PT)+CTR; 4- 5,0mg/kg de PT (5,0PT)+CTR; 5- CTRt+RES; 6- 0,1PT+RES; 7- 1,0PT+RES e 8- 5,0PT+RES. Os animais receberam 31 injeções, uma a cada dia, de propionato de testosterona ou óleo vegetal (i.m) e 15 injeções, em dias alternados, de 0,1 mg/kg de RES ou veículo (s.c.). Durante o tratamento, os animais foram pesados a cada 4 dias e submetidos a testes comportamentais: catalepsia (diariamente) e campo aberto (dia 31). No dia 31, os ratos foram anestesiados, perfundidos, seus cérebros removidos e submetidos a imunohistoquímica para Tirosina Hidroxilase (TH). Mostramos que a administração de RES gera uma resposta sexo-dependente no comportamento de catelepsia e número de células TH+ na Área tegumentar ventral (VTA). Em relação a administração concomitante de PT e RES, observamos que no teste de catalepsia, o tratamento com PT mostrou redução dos efeitos motores, nos machos (exp. I) do grupo 5,0PT+RES, enquanto em fêmeas (exp. II e III) esse efeito foi observado já na dose de 1,0 mg/kg (1,0PT+RES) e também na de 5,0 mg/kg (5,0PT+ RES). Na atividade motora em campo aberto, nenhuma das doses de PT, em nenhum dos experimentos, foi capaz de minimizar os efeitos causados pela RES. Em machos intactos (Exp. I), todas as doses de PT testadas foram capazes de prevenir a diminuição de células TH+ causadas pela RES em VTA, mas não na Substância negra parte compacta. Em fêmeas intactas (Exp. II), apenas a dose de 5,0 mg/kg (5,0PT+RES) foi capaz de prevenir a diminuição de células TH+ na SNpc. Nas fêmeas ovarectomizadas (Exp. III), o tratamento com PT em todas as doses (grupos 0,1PT+RES, 1,0PT+RES e 5,0PT+RES), foi capaz de manter a intensidade de TH no estriado dorsal, prevenindo a redução causada pela RES. O tratamento crônico com PT, no modelo progressivo de parkinsonismo induzido por RES, apresentou diferentes efeitos nos testes comportamentais e nos animais de sexos e condições diferentes, mostrando possíveis mecanismos múltiplos de ação.
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Efeito das variáveis climáticas nas características do sêmen, testosterona e cortisol em bovinos / Influence of year season on semen characteristics and hormones in Nelore an Simental bulls

Mizusaki, Kristoffer Toshiyuki 18 March 2011 (has links)
Made available in DSpace on 2016-01-26T18:55:31Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 371163 bytes, checksum: 00d67c3200895b27fd357306527c561c (MD5) Previous issue date: 2011-03-18 / The objective of this work was to study the seasons influence (spring, summer, autumn and winter) on semen characteristics and hormones (testosterone and cortisol) in Nelore and Simental bulls. Five Nelore and five Simental bulls were 48-72 months old, extensively managed, were evaluated for sexual soundness using physical and morphological characteristics of semen and hormonal serum levels. There was decreased motility and vigor semen (P<0.05) during winter in Simental bulls. There was correlation between serum testosterone and cortisol (P<0.01) to motility and vigor in either Nelore and Simental bulls. In conclusion, these results showed a hormonal and semen characteristics variation throughout the season change the semen quality. Bulls from Nelore breed differed from Simental, demonstrating adaptability to the field conditions. / O objetivo desse trabalho foi estudar a influência das quatro estações do ano: (primavera, verão, outono e inverno), nas características do sêmen e nos níveis de testosterona e cortisol em touros Nelore e Simental. Cinco touros Nelore e cinco Simental com 48-72 meses de idade, criados extensivamente, foram avaliados andrologicamente por meio de exame físico e das características morfológicas do sêmen, concentrações séricas de testosterona e cortisol. Houve queda na motilidade e vigor do sêmen no inverno (p<0,05) para a raça Simental. Houve correlação entre a concentração sérica de testosterona e cortisol (P<0,01) para a motilidade e vigor espermático para os touros Nelore e Simental. Conclui-se que houve variação hormonal e nas características do sêmen ao longo das estações modificando a qualidade do sêmen. Os touros da raça Nelore diferiram dos da raça Simental, demonstrando adaptabilidade às condições do campo.

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