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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.
471

Monitoramento da carga interna de treinamento no voleibol durante a temporada competitiva: comparação entre períodos com número de partidas diferentes / In-season training monitoring in volleyball: comparison between periods with different number of matches

Ramos, Mayara de Faria 12 March 2019 (has links)
O presente estudo teve como objetivo monitorar parâmetros subjetivos: Carga Interna de Treinamento (CIT) e Escala de Qualidade Total da Recuperação (TQR) e objetivos: (cortisol, testosterona e razão T:C) na primeira fase da temporada competitiva, composta por 8 semanas, comparando semanas com duas ou apenas uma partida por semana, em atletas profissionais de Voleibol. Quatorze jogadores profissionais de voleibol participaram da investigação. As variáveis dependentes foram avaliadas durante as 8 primeiras semanas da SuperLiga Masculina de Voleibol, afim de estabelecer a comparação entre semanas com duas partidas e semanas com uma única partida. A CIT foi calculada por semana, pelo método da PSE da sessão, bem como, o índice de monotonia. O escore da TQR e as amostras salivares (analisadas por ELISA) foram coletados semanalmente sempre no primeiro dia útil da semana. Além disso, foi avaliado o desempenho do salto contra movimento (CMJ). Os principais resultados da presente investigação são: o comportamento da CIT refletiu o planejamento da CET. As semanas 2, 3, 7 e 8 (duas partidas por semana) apresentaram maior magnitude de CIT ~6000 UA e as semanas 1, 4, 5 e 6 (uma partida por semana) com menor magnitude de CIT ~4500; o escore da escala TQR sofreu maior redução nas semanas 2, 3, 7 e 8 (duas partidas por semana, apresentando escore de ~6,7 UA) em comparação as semanas 1, 4, 5, 6 (uma partida por semana) que apresentaram escore de ~7,8); as respostas hormonais, testosterona e cortisol, não apresentaram diferenças entre as semanas com uma ou duas partidas disputadas; a maior magnitude das correlações entre as respostas endócrinas e a CIT foi observada nos períodos com duas partidas; foi observado aumento do salto vertical após o período de investigação (TE = 0,30); a associação entre a menor variabilidade semanal na escala de recuperação e melhora do salto. Este estudo revela que o planejamento da CET foi acompanhado pelo comportamento da CIT durante atemporada competitiva, sendo que as semanas com duas partidas apresentaram maior CIT em comparação às semanas com apenas uma partida disputada, que, por sua vez, apresentaram menor CIT. O escore da escala TQR apresentou maior redução nas semanas com duas partidas em comparação às semanas com apenas uma partida. Os hormônios cortisol e testosterona não apresentaram alteração ao longo das 8 semanas de investigação. As correlações entre as variáveis do presente estudo apresentaram maior magnitude nos períodos de maior CET, reforçando a hipótese que em períodos de maior CET, há maior sensibilidade dos parâmetros subjetivos. Por fim, o planejamento adotado, durante as 8 primeiras semanas do período competitivo, foi eficaz para promover aumento do CMJ em jogadores profissionais de voleibol. Os atletas que apresentam a menor variabilidade semanal no escore da TQR apresentaram o maior aumento do CMJ. Esses resultados reforçam a relevância da adoção estratégias de monitoramento integrado, utilizando parâmetros objetivos e subjetivos. Esse constante acompanhamento pode fornecer informações valiosas sobre a forma que os atletas lidam com as demandas da temporada competitiva, auxiliando a retro-alimentação do planejamento da CET ao longo do processo / The current study aimed to monitor subjective parameters: Internal Training Load (ITL) and Total Recovery Quality Scale (TQR) and objectives parameters: (cortisol, testosterone and T: C ratio) during the first phase of the competitive season, comparing weeks with two or only one match per week in professional volleyball players. Fourteen professional volleyball players participated of research. The dependent variables were evaluated during the first 8 weeks of the Men\'s Volleyball SuperLiga, to compare the weeks with 2 matches and the weeks with a single match. ITL was calculated per week by the session RPE method, as well as, the monotony index. The TQR score and the salivary samples (analyzed by ELISA) were collected weekly on the first day of the week. In addition, the performance of the counter movement jump (CMJ) was evaluated. The main results of the present investigation are: ITL reflected the ETL planned. Weeks 2, 3, 7 and 8 (2 matches per week) with a higher magnitude of CIT ~ 6000 AU and weeks 1, 4, 5 and 6 (one match per week) with a lower magnitude of CIT ~ 4500; the TQR score had a greater reduction at weeks 2, 3, 7 and 8 (2 matches per week, presenting a score of ~6.7 AU) compared to weeks 1, 4, 5, 6 (one match per week) presenting a score of ~ 7.8); the endocrine responses did not show differences between the weeks with 2 or 1 matches played; the greater magnitude of the correlations between the endocrine responses and the ITL was observed in weeks with 2 matches; there was an increase in CMJ after the investigation period and (Effect Size = 0,30); the association between the lower weekly variability in the recovery scale (TQR) and the improvement in the CMJ. This study reveals that the ETL planning was accompanied by the ITL during the competitive season, and the weeks with 2 matches had a higher ITL compared to the weeks with only 1 match played, which, in turn, presented lower ITL. The TQR score showed a greater reduction in the weeks with 2 matches compared to the weeks with only 1 match played, following the ITL behavior. The hormonal responses were not affected during the 8 weeks of investigation, withoutdifference between the weeks with 2 or 1 match disputed. The correlations between the variables of this research showed greater magnitude in weeks of higher ETL (2 matches), reinforcing the hypothesis that in periods of higher ETL, there is greater sensitivity of the subjective parameters. Finally, the ETL periodization adopted, during the first 8 weeks of the competitive period, was effective to promote increase of CMJ in professional players of volleyball. The athletes with the lowest weekly variability in the TQR score had the highest increase in CMJ. These results reinforce the relevance of adopting integrated monitoring strategies, using objective and subjective parameters. This constant monitoring can provide valuable insight into how athletes cope with the demands of the competitive season, provinding feed-back for the ETL planning throughout the process
472

Influência da idade, sexo e dos hormônios gonadais na percepção dolorosa em modelo de dor neuropática em ratos / Influence of age, sex and gonadal hormones on pain perception in neuropathic pain model in rats

Palmeira, Claudia Carneiro de Araujo 23 October 2014 (has links)
Os fatores idade e sexo modificam a experiência dolorosa em animais e seres humanos. Os efeitos dos hormônios gonadais têm sido estudados em diversos modelos experimentais de dor, no entanto, o efeito do envelhecimento na percepção à dor carece de mais investigação. O efeito do envelhecimento na dor neuropática ainda não está bem estabelecido. Neste estudo se procurou avaliar possíveis variações na percepção da dor da hiperalgesia mecânica, em função da idade, presença e ausência de hormônios gonadais e sexo em ratos Wistar machos e fêmeas, jovens e idosos no modelo de dor neuropática, ligadura da quinta raiz lombar. Os animais foram divididos nos seguintes grupos: ratos jovens orquiectomizados e não-orquiectomizados, ratos idosos orquiectomizados e não-orquiectomizados, ratas jovens ooforectomizadas com ou sem reposição de 17beta-estradiol e ratas idosas. Foi testado o limiar de retirada da pata após estímulo mecânico antes da ligadura e no 7º, 14º, 21º e 28o dias após a ligadura. Os resultados mostraram que todos os animais apresentaram comportamento hiperalgésico após ligadura da quinta raiz lombar durante os 28 dias de observação. A hiperalgesia ocorreu independentemente do sexo do animal, da presença ou ausência de hormônios gonadais ou idade. Não houve diferença entre ratos jovens e idosos não-orquiectomizados (p = 0,420), entre ratos jovens e idosos orquiectomizados (p = 0,560). Entre os ratos idosos com e sem orquiectomia houve diferença no 14º (p = 0,038) e 28º (p = 0,002) dias. Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol apresentaram menor hiperalgesia que ratas ooforectomizadas com reposição durante todo o período (p = 0,001). Não houve diferença entre ratos idosos orquiectomizados e ratas idosas (p = 0,09). Ratos jovens não-orquiectomizados apresentaram menor hiperalgesia mecânica que ratas jovens ooforectomizadas com reposição de 17beta-estradiol (p = 0,001), o mesmo não ocorreu entre machos e fêmeas jovens gonadectomizados sem reposição hormonal (p = 0,511). Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol e ratas idosas mostraram diferença apenas no 7º dia (p = 0,002). Os resultados permitiram concluir que a reposição de 17beta-estradiol aumentou a hiperalgesia mecânica aos estímulos mecânicos após ligadura da quinta raiz lombar em ratas jovens ooforectomizadas, a hiperalgesia mecânica não diferiu entre os sexos em ratos jovens machos e fêmeas, a presença da gônada masculina diminuiu a hiperalgesia mecânica em ratos idosos e que houve diminuição da hiperalgesia mecânica em ratas idosas / Age and sex modify the pain experience in animals and humans. The effects of gonadal hormones have been studied in various experimental pain models, however, the effect of aging on pain perception needs further investigation. The effect of aging on neuropathic pain is not well established. In this study, we sought to determine how aging and gonadal hormones affect mechanical hyperalgesia using spinal nerve ligation as a neuropathic pain model in aged and young male and female Wistar rats. Animals were divided into seven groups: aged female, ovariectomized young females with 17beta-estradiol replacement, ovariectomized young females without 17beta-estradiol replacement, orchiectomized and non-orchiectomized aged and young males. Rats were tested for mechanical hyperalgesia in the plantar surface of the left hindpaw before nerve ligation and on days 7, 14, 21 and 28 after nerve ligation. All animals of all groups showed mechanical hyperalgesic behavior after spinal nerve ligation during entire period of 28 days. Hyperalgesia was independent of the sex of the animal, the presence or absence of gonadal hormones or age. There was no difference between non-orchiectomized aged and young males (p = 0.420), and between orchiectomized aged and young males (p = 0.560). There was difference between aged male rats with and without orchiectomy in days 14 (p = 0.038) and 28 (p = 0.002). Young ovariectomized female rats without 17beta-estradiol replacement had less hyperalgesia than young ovariectomized female rats with replacement (p = 0.001). There was no difference between aged orchiectomized male rats and old female rats (p = 0.09). Young non-orchiectomized male rats showed less mechanical hyperalgesia than young ovariectomized female rats with 17beta-estradiol replacement (p = 0.001), that did not occur between young orchiectomized males rats and young ovariectomized females rats without 17beta-estradiol replacement (p = 0.51). Young ovariectomized female rats without 17beta-estradiol replacement and old female rats showed differences only on day 7 (p = 0.002). These data suggest that estradiol presented a pronociceptive effect in young female rats in mechanical hyperalgesia in the neuropathic pain model, spinal nerve ligation, withdrawal threshold did not differ between sex, the presence of male gonadal hormones reduces mechanical hyperalgesia in old male rats and there is reduced mechanical hyperalgesia in aged female rats
473

Novas perspectivas no papel da vitamina D e sua influência com a qualidade do sêmen e hormônios sexuais em homens / New perspectives into the positive role of vitamin \"D\" in determining better sperm quality and higher testosterone levels in men

Inarí Marina Inti Ciccone 07 December 2018 (has links)
A vitamina D é uma molécula versátil que possui ação genômica e não genômica em múltiplas reações dos seus órgãos que possuem a expressão de seu receptor (VDR), inclusive do trato reprodutivo de ambos os sexos, além dos seus clássicos efeitos no metabolismo ósseo, e na homeostase do cálcio e fosfato. Novas evidências a partir de estudos experimentais e com humanos sugerem que a vitamina D está envolvida nas funções dos órgãos reprodutivos masculinos, influenciando na espermatogênese. O objetivo do presente estudo foi avaliar a influência dos níveis séricos de 25(OH)D com os parâmetros de qualidade seminal em homens normozoospérmicos e com alterações nos parâmetros seminais. Nesse estudo retrospectivo, dos 508 pacientes atendidos no período de 2009 até 2017 com todas as dosagens séricas e análise seminal, selecionamos os dados de 260 pacientes que atenderam aos critérios de inclusão, de uma clínica médica de Andrologia da cidade de São Paulo. Eles foram divididos em dois grupos: Grupo normozoospermicos (NZG; N=124) e Grupo com parâmetros Seminais Alterados (SAG; N=136). Foram considerados as dosagens séricas de 25(OH)D, e as variáveis de confusão ambientais, como uso de álcool, tabaco, sedentarismo, índice de massa corporal (IMC), e presença de varicocele. As analises seminais foram realizadas e classificadas de acordo com o manual da OMS 2010, e foram consideradas para o estudo os parâmetros de pH, volume, motilidade total e progressiva, morfologia por OMS e Kruger. Além disso, foram consideradas os exames de Cariótipo e Micro deleção no Cromossomo Y. As análises estatísticas foram realizadas com o SPSS versão 19.0. Correlação de Spearman, Mann-Whitney e um modelo de regressão multivariada foram aplicadas. Significância considerada foi de P <= 0.05. A distribuição das médias dos níveis séricos de 25(OH)D foi significativamente menor nos pacientes do grupo com parâmetros seminais alterados (P =0.016), e foi encontrado uma correlação positiva entre os níveis séricos de 25(OH)D e todos os parâmetros de qualidade seminal analisados, excetos de pH e volume. Foi descrita correlação forte entre 25(OH)D e motilidade total (r=0,225; P =0,001). Os resultados obtidos nesse estudo mostram que os níveis séricos de 25(OH)D possuem uma correlação positiva com os parâmetros de motilidade, concentração e morfologia do espermatozoide, de forma independente. Esses achados indicam que a adequação dos níveis de vitamina D podem ser um importante coadjuvante no tratamento da infertilidade masculina / Vitamin D is a versatile signaling molecule, that targets also male reproductive organs, in addition to the classic effects on bone, calcium and phosphate homeostasis. Accumulating evidence from animal and human studies suggests that it is involved in reproduction functions in both genders. This study aimed to evaluate the vitamin D correlation with semen quality in male with seminal parameters alteration and normozoospermic diagnosis. We selected 260 men (aged 18 to 60 y.o.) from a private andrology reference medical clinic for this observatory study. They were divided in two groups: Normal seminal parameters (NZG N=124) and Abnormal seminal parameters (SAG N=136). 25(OH) vitamin D serum concentration were collected such as lifestyle data available. Semen was analyzed according to WHO 2010 guidelines, ph, volume, motility, concentration, morphology, strict criteria and sperm functional tests were performed (ROS, CK, beads). In addition, karyotype, frequency of varicocele, smoking, alcohol ingestion, and body composition were considered. Statistical analysis was performed by SPSS program version 19.0 (SPSS Inc., Chicago, IL). Spearman correlation, Mann-Whitney test and regression model were applied. Statistical significance was considered with P value < 0. 05. The 25(OH)D average distribution concentration were significant lower in Abnormal seminal parameters group (P =0.016), and all parameters had a positive correlation with 25(OH)D serum levels. The highest coefficient value was observed in the association of total motility with Vitamin D (P =0.001). Our results demonstrated that 25(OH)D levels has a positive influence on spermatogenesis and semen quality, suggesting that vitamin D replacement should highly be concerned on male fertility treatment
474

Investigations on the in vitro effects of aqueous Eurycoma longifolia Jack extract on male reproductive functions

Erasmus, Nicolete January 2012 (has links)
<p>Eurycoma longifolia (Tongkat Ali / TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is also used to improve male fertility and no report&nbsp / regarding its safety has been published, this study investigated the effects of a patented, aqueous TA extract on various sperm and testicular functions. Materials and Methods This study&nbsp / encompasses two parts (part 1: on spermatozoa / part 2: on TM3-Leydig and TM4-Sertoli cells). Part 1: Semen samples of 27 patients and 13 fertile donors were divided into two groups,&nbsp / washed and swim-up prepared spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 &mu / g/ml) for 1 hour at 37&deg / C. A sample without addition of TA served as control. After incubation with TA,&nbsp / the following parameters were evaluated: viability (Eosin-Nigrosin test), total and progressive motility (CASA), acrosome reaction (triple stain technique), sperm production of reactive oxygen&nbsp / species (ROS / dihydroethidium test / DHE), sperm DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (&Delta / &psi / m) (Depsipher kit). Part 2: TM3-Leydig and TM4-Sertoli cells&nbsp / incubated with different concentrations of TA (0.4, 0.8, 1.6, 3.125, 6.25, 12.5, 25, 50 &mu / g/ml) and control (without extract) for 48 and 96 hours. After incubation with TA, the following parameters were&nbsp / evaluated: viability (XTT), cell proliferation (protein assay), testosterone (testosterone ELISA test) and pyruvate (pyruvate assay). Results Part 1: For washed spermatozoa, significant&nbsp / dose-dependent trends were found&nbsp / for viability, total motility, acrosome reaction and sperm ROS production. However, these trends were only significant if the highest concentrations were included in the calculation. In the swim-up spermatozoa, ROS production of spermatozoa showed a biphasic relationship with its lowest percentage at 10 &mu / g/ml, yet, no significance could be&nbsp / observed (P=0.9505). No influence of TA could be observed for sperm DNA fragmentation nor &Delta / &psi / m.</p>
475

Investigations on the in vitro effects of aqueous Eurycoma longifolia Jack extract on male reproductive functions

Erasmus, Nicolete January 2012 (has links)
<p>Eurycoma longifolia (Tongkat Ali / TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is also used to improve male fertility and no report&nbsp / regarding its safety has been published, this study investigated the effects of a patented, aqueous TA extract on various sperm and testicular functions. Materials and Methods This study&nbsp / encompasses two parts (part 1: on spermatozoa / part 2: on TM3-Leydig and TM4-Sertoli cells). Part 1: Semen samples of 27 patients and 13 fertile donors were divided into two groups,&nbsp / washed and swim-up prepared spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 &mu / g/ml) for 1 hour at 37&deg / C. A sample without addition of TA served as control. After incubation with TA,&nbsp / the following parameters were evaluated: viability (Eosin-Nigrosin test), total and progressive motility (CASA), acrosome reaction (triple stain technique), sperm production of reactive oxygen&nbsp / species (ROS / dihydroethidium test / DHE), sperm DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (&Delta / &psi / m) (Depsipher kit). Part 2: TM3-Leydig and TM4-Sertoli cells&nbsp / incubated with different concentrations of TA (0.4, 0.8, 1.6, 3.125, 6.25, 12.5, 25, 50 &mu / g/ml) and control (without extract) for 48 and 96 hours. After incubation with TA, the following parameters were&nbsp / evaluated: viability (XTT), cell proliferation (protein assay), testosterone (testosterone ELISA test) and pyruvate (pyruvate assay). Results Part 1: For washed spermatozoa, significant&nbsp / dose-dependent trends were found&nbsp / for viability, total motility, acrosome reaction and sperm ROS production. However, these trends were only significant if the highest concentrations were included in the calculation. In the swim-up spermatozoa, ROS production of spermatozoa showed a biphasic relationship with its lowest percentage at 10 &mu / g/ml, yet, no significance could be&nbsp / observed (P=0.9505). No influence of TA could be observed for sperm DNA fragmentation nor &Delta / &psi / m.</p>
476

Profil et déterminants comportemental et physiologique de l’ascension à la dominance en milieu naturel chez les femelles d’une espèce de poisson hautement sociale

St-Cyr, Sophie 03 1900 (has links)
Malgré le fait que le statut social soit reconnu comme ayant une forte influence sur l’aptitude, les facteurs affectant le statut social et les changements de ce statut demeurent peu connus. De plus, les études sur la dominance ayant un lien avec l’agressivité portent rarement sur des femelles. Nous étudierons ces aspects en utilisant Neolamprologus pulcher, un poisson à reproduction coopérative du lac Tanganyika. La probabilité d’ascension sociale était manipulée sur le terrain et les changements physiologiques et comportementaux, ainsi que le niveau plasmatique de testostérone, associé avec l’ascension à la dominance de femelles subordonnées étaient caractérisés. Le degré de coopération et la masse étaient supérieurs chez les femelles ascendantes par rapport aux femelles non-ascendantes d’un même groupe social. Après une semaine d’ascension sociale, les femelles ascendantes ne différaient pas comportementalement, mais différaient physiologiquement des femelles dominantes. Les femelles dominantes, ascendantes et subordonnées ne différaient pas quant au niveau de testostérone plasmatique. Comprendre les bénéfices des comportements coopératifs pour les subordonnés a longtemps posé un problème évolutif. Nos résultats impliquent que les comportements coûteux métaboliquement peuvent avoir été sélectionnés en améliorant l’aptitude future via l’héritage du territoire et du statut social. De plus, le degré de coopération pourrait être un signal de qualité détecté par les compétiteurs et les collaborateurs. / Although social rank is known to have a strong influence on fitness, factors affecting rank and changes in rank remain poorly understood. In addition, studies of dominance and its relation to aggression rarely focus on females. We address these issues in this study using Neolamprologus pulcher, a cooperatively breeding fish species from Lake Tanganyika. The probability of social ascension was manipulated in the field and the physiological and behavioural changes as well as plasma testosterone level associated with subordinate female ascension were characterized. Both helping effort (degree of cooperation) and body size were greater in ascending versus paired same social group non-ascending females. After one week of social ascension, ascending females did not differ behaviourally but were physiologically different (higher body condition, smaller, lighter) from dominant females. Dominant, ascending females and subordinate females did not differ in plasma testosterone levels. Understanding the benefits of helping behaviour for subordinates has long been an evolutionary challenge and our results imply that this costly metabolic behaviour may have been selected by enhancing future fitness via territory and rank inheritance. Furthermore, helping effort could be a signal of quality detected by both competitors and collaborators.
477

The impact of exogenous TGFβ1 on male reproductive function.

McGrath, Leanne Jane January 2008 (has links)
The TGFβ family of cytokines are potent signalling molecules that regulate tissue development, inflammation and immunity. Previous studies in mice with a null mutation in the Tgfb1 gene (TGFβ1-/- mice) implicate a key role for TGFβ1 in male reproductive function. These mice show profound infertility due to an inability to copulate successfully, associated with reduced testosterone and sperm production. The focus of this project was to 1) further characterize mechanisms underpinning reproductive deficiency in male TGFβ1-/- mice, 2) identify a reliable physiological marker of TGFβ1 availability in vivo, and 3) to determine whether exogenous TGFβ1 administration influences TGFβ1 availability and restores fertility. To investigate the causes of unsuccessful copulation by TGFβ1-/- mice, penis morphometry was examined. Penile organ structure, as assessed by scanning electron microscopy, was comparable between genotypes however a superfluous epidermal covering that impeded penile spine protrusion was evident in TGFβ1-/- mice. The epidermal covering was not due to increased epithelial cell proliferation, as measured by Brdu labelling and immunohistology. Behavioural observations of erectile activity showed that TGFβ1-/- mice achieved spontaneous erections albeit at reduced frequency compared to TGFβ1+/+ mice. The efficacy of exogenous TGFβ1 replacement was evaluated by first identifying measures of in vivo TGFβ1 availability and/or function and selecting an effective route of administration. Serum TGFβ1 and testosterone levels were reliable discriminators of TGFβ1 genotype. Gene expression and phagocytic function of peritoneal macrophages revealed no differences between genotypes. Exogenous sources of TGFβ1 for replacement studies included colostrum, naturally occurring in breast milk and recombinant human latent TGFβ1 (rhLTGFβ1). Colostrum did not increase circulating levels and rhTGFβ1 injection caused only transient elevation of serum levels. Thus mini-osmotic pumps were used to deliver a constant supply of cytokine to TGFβ1-/- mice. The fertility status of TGFβ1-/- mice receiving exogenous TGFβ1 was investigated. Reproductive behaviour in response to normal receptive female mice was assessed twice during treatment, on day 7 and day 14. Blood, liver and reproductive tissues were collected at sacrifice. Circulating TGFβ1 was increased in TGFβ1 treated TGFβ1-/- mice above TGFβ1-/- control levels, although this did not affect circulating testosterone. Erectile activity and sperm production were unchanged. Videotaping behaviour with estrous females revealed that the TGFβ1+/+ mice successfully mounted and intromitted, unlike the TGFβ1-/- controls. The TGFβ1-/- mice receiving exogenous TGFβ1 displayed moderately enhanced mounting and intromission behaviour although this remained less frequent than in the TGFβ1+/+ controls. Ejaculation behaviour was not observed in any TGFβ1-/- mice regardless of TGFβ1 replacement, compared to TGFβ1+/+ controls where >90% mice displayed ejaculated. Modest improvement in the copulation activity of the TGFβ1-/- mice receiving exogenous TGFβ1 suggests that systemic TGFβ1 availability can influence reproductive performance in male TGFβ1-/- mice. However since fertility was not restored, locally produced TGFβ1 in the reproductive tract and/or hypothalamic pituitary axis are also implicated in regulating fertility. These findings advance our knowledge of the role of the TGFβ1 cytokine in male reproductive physiology and may have relevance for devising new treatments for infertility and erectile dysfunction in men. / Thesis (Ph.D.) - University of Adelaide, School of Paediatrics and Reproductive Health, 2008
478

Statut endocrinien et effort de reproduction chez un oiseau marin longévif, le manchot Adélie, dans un environnement changeant / Endocrine status and reproductive effort of a long-lived seabird, the Adélie penguin, in a changing environment

Thierry, Anne-Mathilde 13 September 2013 (has links)
L’étude des mécanismes endocriniens est particulièrement intéressante du fait du rôle majeur des hormones dans la régulation des interactions entre la physiologie d’un organisme, son comportement, et les modifications de son environnement. Cette thèse s’est intéressée aux relations entre le statut hormonal, les performances de reproduction et le succès reproducteur d’un oiseau marin longévif, le manchot Adélie Pygoscelis adeliae, dans un contexte environnemental soumis à des changements. Le statut endocrinien de manchots mâles a été manipulé en utilisant des implants dégradables sous-cutanés diffusant l’hormone d’intérêt ou un inhibiteur de sa sécrétion. Les effets d’une modification des niveaux d’hormones sur l’investissement parental pendant l’incubation ont été mesurés à l’aide d’observations directes et d’oeufsfactices enregistrant les paramètres d’incubation. Les niveaux de corticostérone – hormone dite de stress, de prolactine – hormone des soins parentaux, et de testostérone – hormone liée aux comportements sexuels et à l’agressivité, ont été manipulés. Les effets d’une augmentation des niveaux de corticostérone sur les performances et le succès reproducteur pendant la période de l’élevage des poussins ont également été mesurés. Enfin, les conséquences d’une légère élévation des niveaux de corticostérone pendant l’ensemble de la saison de reproduction en termes de comportement et de succès reproducteur ont été examinées. Une augmentation des niveaux de corticostérone a globalement diminué les performances et le succès de reproduction. D’autre part, une modification des niveaux de prolactine ou de testostérone a affecté la durée etles paramètres d’incubation, suggérant une implication de ces deux hormones dans le contrôle de la phénologie de la reproduction. Les résultats présentés dans cette thèse mettent l’accent sur le fait que la relation entre statut endocrinien et performances de reproduction est dose, état et contexte dépendante. Nos résultats illustrent le rôle majeur des hormones étudiées dans la régulation de l’effort reproducteur, et soulignent également l’importance de considérer les interactions entre les organismes et leur environnement. / Studying endocrine mechanisms is of particular interest because of the major role played by hormones in mediating interactions between an animal’s physiology, its behaviour, and both predictable and unpredictable regimes of environmental variation. During this PhD, I have investigated the relationships between endocrine status, reproductive performance, and reproductive output in a long-lived polar seabird, the Adélie penguin Pygoscelis adeliae, while integrating environmental parameters for some of the studies. The endocrine status of male penguins was experimentally modified using subcutaneous self-degradable pellets, which released either the hormone or an inhibitor of its secretion. The effects of changes in the levels of several hormones on the parental investment during incubation were assessed, using direct observations and dummy eggs to record incubation parameters. The levels of corticosterone – the so-called stress hormone, prolactin – the parental care hormone, and testosterone – the sexual behaviour and aggressiveness hormone, were manipulated. The effects of increased corticosterone levels on reproductive performance and output were also evaluated during the chick-rearing period. Finally, the behavioural consequences of a moderate elevation of corticosterone levels during the whole breeding cycle were assessed. On the whole, an increase in corticosterone levels decreased reproductive performances and output. Changes in prolactin or testosterone levels affected incubation duration and egg temperature, suggesting a role for these hormones in the control of the timing of breeding. The results prevented in this PhD highlight the fact that the relationship between endocrine status and reproductive performance is dose-, state-, and context-dependant. Our results illustrate the major role of the hormones considered in our studies in the regulation of reproductive effort. They also underline the importance of considering the interactions of organisms with their environment in studies of animal behaviour and ecophysiology.
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Influência da idade, sexo e dos hormônios gonadais na percepção dolorosa em modelo de dor neuropática em ratos / Influence of age, sex and gonadal hormones on pain perception in neuropathic pain model in rats

Claudia Carneiro de Araujo Palmeira 23 October 2014 (has links)
Os fatores idade e sexo modificam a experiência dolorosa em animais e seres humanos. Os efeitos dos hormônios gonadais têm sido estudados em diversos modelos experimentais de dor, no entanto, o efeito do envelhecimento na percepção à dor carece de mais investigação. O efeito do envelhecimento na dor neuropática ainda não está bem estabelecido. Neste estudo se procurou avaliar possíveis variações na percepção da dor da hiperalgesia mecânica, em função da idade, presença e ausência de hormônios gonadais e sexo em ratos Wistar machos e fêmeas, jovens e idosos no modelo de dor neuropática, ligadura da quinta raiz lombar. Os animais foram divididos nos seguintes grupos: ratos jovens orquiectomizados e não-orquiectomizados, ratos idosos orquiectomizados e não-orquiectomizados, ratas jovens ooforectomizadas com ou sem reposição de 17beta-estradiol e ratas idosas. Foi testado o limiar de retirada da pata após estímulo mecânico antes da ligadura e no 7º, 14º, 21º e 28o dias após a ligadura. Os resultados mostraram que todos os animais apresentaram comportamento hiperalgésico após ligadura da quinta raiz lombar durante os 28 dias de observação. A hiperalgesia ocorreu independentemente do sexo do animal, da presença ou ausência de hormônios gonadais ou idade. Não houve diferença entre ratos jovens e idosos não-orquiectomizados (p = 0,420), entre ratos jovens e idosos orquiectomizados (p = 0,560). Entre os ratos idosos com e sem orquiectomia houve diferença no 14º (p = 0,038) e 28º (p = 0,002) dias. Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol apresentaram menor hiperalgesia que ratas ooforectomizadas com reposição durante todo o período (p = 0,001). Não houve diferença entre ratos idosos orquiectomizados e ratas idosas (p = 0,09). Ratos jovens não-orquiectomizados apresentaram menor hiperalgesia mecânica que ratas jovens ooforectomizadas com reposição de 17beta-estradiol (p = 0,001), o mesmo não ocorreu entre machos e fêmeas jovens gonadectomizados sem reposição hormonal (p = 0,511). Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol e ratas idosas mostraram diferença apenas no 7º dia (p = 0,002). Os resultados permitiram concluir que a reposição de 17beta-estradiol aumentou a hiperalgesia mecânica aos estímulos mecânicos após ligadura da quinta raiz lombar em ratas jovens ooforectomizadas, a hiperalgesia mecânica não diferiu entre os sexos em ratos jovens machos e fêmeas, a presença da gônada masculina diminuiu a hiperalgesia mecânica em ratos idosos e que houve diminuição da hiperalgesia mecânica em ratas idosas / Age and sex modify the pain experience in animals and humans. The effects of gonadal hormones have been studied in various experimental pain models, however, the effect of aging on pain perception needs further investigation. The effect of aging on neuropathic pain is not well established. In this study, we sought to determine how aging and gonadal hormones affect mechanical hyperalgesia using spinal nerve ligation as a neuropathic pain model in aged and young male and female Wistar rats. Animals were divided into seven groups: aged female, ovariectomized young females with 17beta-estradiol replacement, ovariectomized young females without 17beta-estradiol replacement, orchiectomized and non-orchiectomized aged and young males. Rats were tested for mechanical hyperalgesia in the plantar surface of the left hindpaw before nerve ligation and on days 7, 14, 21 and 28 after nerve ligation. All animals of all groups showed mechanical hyperalgesic behavior after spinal nerve ligation during entire period of 28 days. Hyperalgesia was independent of the sex of the animal, the presence or absence of gonadal hormones or age. There was no difference between non-orchiectomized aged and young males (p = 0.420), and between orchiectomized aged and young males (p = 0.560). There was difference between aged male rats with and without orchiectomy in days 14 (p = 0.038) and 28 (p = 0.002). Young ovariectomized female rats without 17beta-estradiol replacement had less hyperalgesia than young ovariectomized female rats with replacement (p = 0.001). There was no difference between aged orchiectomized male rats and old female rats (p = 0.09). Young non-orchiectomized male rats showed less mechanical hyperalgesia than young ovariectomized female rats with 17beta-estradiol replacement (p = 0.001), that did not occur between young orchiectomized males rats and young ovariectomized females rats without 17beta-estradiol replacement (p = 0.51). Young ovariectomized female rats without 17beta-estradiol replacement and old female rats showed differences only on day 7 (p = 0.002). These data suggest that estradiol presented a pronociceptive effect in young female rats in mechanical hyperalgesia in the neuropathic pain model, spinal nerve ligation, withdrawal threshold did not differ between sex, the presence of male gonadal hormones reduces mechanical hyperalgesia in old male rats and there is reduced mechanical hyperalgesia in aged female rats
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"Líquen escleroso vulvar: estudo dos marcadores Ki-67 e p53 antes e após o tratamento com clobetasol a 0,05%, testosterona a 2% e um placebo" / Vulvar lichen sclerosus: a study of markers Ki-67 and p53 before and after the treatment with clobetasol at 0.05%, testosterone at 2% and a placebo

Patricia Andreucci Gomes 02 February 2006 (has links)
O líquen escleroso vulvar é uma doença crônica e benigna, porém apresenta um potencial de malignização para o carcinoma de células escamosas de vulva. Foram estudadas trinta doentes com líquen escleroso vulvar, divididas em três grupos, que fizeram uso tópico de propionato de clobetasol a 0,05%, testosterona a 2% e um placebo, para avaliar a evolução dos sintomas e o comportamento das células marcadas com o anticorpo Ki-67 e a proteína p53 antes e após os tratamentos. Observou-se melhora dos sintomas clínicos com o uso do clobetasol e da testosterona, que foi estatisticamente superior ao placebo (p<0,01). Observou-se diminuição significante das células marcadas com Ki-67 após o tratamento das doentes com o clobetasol (p<0,01) e com a testosterona (p<0,02). Enquanto, nas doentes que utilizaram placebo, observou-se um aumento do Ki-67. Em relação à análise das células marcadas com a proteína p53 também observou-se diminuição significante após o tratamento com o clobetasol (p<0,01) e com a testosterona (p<0,01). Enquanto no grupo placebo observou-se um aumento do p53. Quando se compara a variação do p53 entre os grupos clobetasol, testosterona e placebo observou-se uma diminuição do p53 estatisticamente superior (p<0,001) nas doentes que utilizaram clobetasol. Assim, os resultados mostram uma redução dos marcadores celulares após os tratamentos, e com o p53 a diminuição foi estatisticamente maior no grupo que utilizou clobetasol, sugerindo a eficácia desse tratamento / Vulvar Lichen Sclerosus consists of a benign chronic disease, however featuring a malignant potential for vulvar squamous cell carcinoma. The present study targeted 30 patients diagnosed Vulvar Lichen Sclerosus, divided in three groups, and who made topical use of clobetasol propionate at 0.05%, testosterone at 2% and a placebo, so as to assess the evolution of the symptoms and the behavior of the cells marked with antibody Ki-67 and protein p53, before and after the treatments. The administration of clobetasol and testosterone has proven effective in the management of the clinical symptoms, which turned out to be statistically higher than the placebo (p<0.01). The number of cells marked with Ki-67 decreased significantly patients treated with clobetasol (p<0.01) and testosterone (p<0.02), while the number of such cells increased in those patients who made use of the placebo. The number of cells marked with protein p53 also decreased significantly after the treatment with clobetasol (p<0.01) and testosterone (p<0.01), whereas the placebo group revealed an increased p53. When comparing the decrease of the p53 in the clobetasol, testosterone and placebo groups, we noted a decrease of the p53 statistically higher (p<0.001) in patients under clobetasol; suggesting a reduction in the cellular markers after the treatment. As for the p53, the decrease was statistically higher in the group under clobetasol, suggesting the efficacy of the treatment.

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