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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.
11

Alterações semelhantes à capacitação no sêmen bovino após a criopreservação utilizando diluidores a base de gema de ovo ou lecitina de soja / Capacitation-like changes in bovine semen after cryopreservation using extenders within egg yolk or soy lecithin

Fabiane Gilli Zaffalon 11 December 2009 (has links)
O objetivo deste estudo foi avaliar os efeitos de três diluidores diferentes na criopreservação do sêmen bovino sobre a motilidade, hiperativação espermática, reação acrossomal, capacitação e peroxidação lipídica das membranas espermáticas. Foram realizadas seis colheitas de sêmen em intervalos quinzenais de dez touros zebuínos da raça Nelore. O sêmen in natura foi avaliado, dividido em três tratamentos: uma fração foi diluída em meio a base de gema de ovo (Botu-Bov® - diluidor 1), a segunda fração diluída em meio a base de lecitina de soja (Botu-Bov® - diluidor 2) e a terceira fração em meio AndroMed® (diluidor 3) também a base de lecitina de soja. Logo após as amostras foram submetidas à congelação. As avaliações do sêmen após descongelação consistiram na análise computadorizada das características de motilidade e nas análises pela citometria de fluxo quanto à reação acrossomal (PI/FITC-PSA/H33342); peroxidação lipídica (PI/C11-BODIPY581/591/H33342) e capacitação espermática através da estabilidade da membrana plasmática (Merocianina 540/Yo-Pro1/H33342). As variáveis foram submetidas à análise de variância e ao teste LSD para comparação das médias, ao nível de 5% de significância. O diluidor a base de gema de ovo preservou melhor a motilidade espermática, a população de células com integridade de membrana plasmática e acrossomo não reagido no sêmen bovino pós-descongelação que os diluidores a base de lecitina de soja. Os espermatozóides criopreservados com o diluidor a base de gema de ovo apresentou menor sub população de células hiperativas e com membrana plasmática desestabilizada quando comparados com os diluidores a base de lecitina de soja e o diluidor a base de gema de ovo possibilitou uma diminuição da peroxidação lipídica das membranas espermáticas / The objective of this experiment was evaluate the effects of three diferent extenders in bovine semen cryopreservation about motility, sperm hiperactivation, acrosome reaction, capacitation, and sperm membrane lipid peroxidation. It was made six collection of semen samples each 15 days of 10 Nelore bulls. Semen samples in natura was verify and divided in three treatments: The first one was extended in egg yolk base (Botu-Bov® Extender 1), second one was extended in soy lecithin base (Botu-Bov® Extender 2) and the third was extended in AndroMed® soy lecithin base too. After that, semen samples were submitted to freeze process. Semen evaluations after thawing were made with computer assisted sperm analysis (CASA) and flow citometry for acrosome reaction (PI/FITC-PSA/H33342), lipid peroxidation (PI/C11-BODIPY581/591/H33342) and sperm capacitation by plasma membrane stability (Merocianina 540/Yo-Pro1/H33342). Data obtained from experimental proceeding were submitted to variance analysis and LSD test to compare means with 5% of significance. Egg yolk base extender preserved better sperm motility, cell population with plasma membrane integrity and non-reacted acrosome in bovine semen after thawing than soy lecithin extenders. Cryopreserved sperm with egg yolk base extender displayed less subpopulation of hiperactivated cells, less destabilized plasma membrane and permitted a decrease of lipid peroxidation of membranes when it was compared with soy lecithin extender
12

Akrozomální reakce spermií u vybraných druhů savců / Sperm acrosomal reactien in selected species of mammals

Frolíková, Michaela January 2015 (has links)
Mammalian sperm must undergo the process of capacitation - series of physiological and biochemical modifications prior fertilization. In last stage of capacitation sperm undergoes acrosome reaction (AR). During AR the cell membrane of the sperm fuses with the outer acrosomal membrane and the contents of acrosomal vesicle are released into extracellular space. Sperm which did not undergo AR or sperm missing acrosome at all are unable to fertilize. AR results into dramatical changes in the sperm head. Most of the proteins present in plasmatic and outer acrosomal membrane are reorganized or lost. There are also significant changes in cytoskeletal and intraacrosomal proteins are released to extracellular space uncovering new surface domains. Some sperms undergo AR even without presence of inductor of AR during capacitation in vitro. This event is called spontaneous (accelerated) AR. The latest research indicates that spontaneous AR is natural part of the process of fertilization. Field mice (Apodemus) show high level of promiscuity leading to significant risk of sperm competition. Unique reproduction strategy where the sperms form so-called sperm trains was evolved in field mice. Spontaneous AR is probably enabling the dissociation of sperms from the sperm train. The spontaneous AR rate is dependent on...
13

Chemické signály a reprodukční procesy u myši domácí (Mus musculus) / Chemical signals and reproductive processes of the house mouse (Mus musculus)

Černá, Martina January 2017 (has links)
The aim of my thesis was to identify proteins involved in chemical communication and especially those that are involved in sexual signalling. Volatile chemical signals are transported with lipocalins in their beta-barrel structure to present their ligands to receptors or out of the body. Thus, I focused on the identification of these proteins in saliva and vaginal secretion of the house mouse using proteomic and transcriptomic approaches. Due to a cyclic manner of reproduction and its hormonal control, I have also focused on the role of estradiol on sperm phenotype in the laboratory mouse. We have identified an elevated sexual dimorphism in several lipocalins (i.e. 10 out of 20) in the saliva proteome where they may play a role in sexual signalling (i.e. similar to their described roles in the mouse urine). Interestingly, vaginal secretion also contains lipocalins and they rise from proestrus to estrus and remain steady during metestrus. Such variation provides evidence that they serve sexual signalling, however, due to their elevated levels during metestrus it is most likely that their ligands function as signals and not the proteins themselves. On the level of sperm phenotype, we have provided evidence, that experimental concentrations of estradiol have differential effects on sperm. This is due...
14

Vliv estrogenních hormonů na kapacitaci a akrozomální reakci myších spermií in vitro / The influence of estrogens on mouse sperm capacitation and acrosome reaction in vitro

Tejnická, Magda January 2011 (has links)
There are an increasing amount of compounds in the environment that can have a negative effect on reproductive parameters in both male and female organism. There has been a worldwide decline of sperm quality during past decades and this fact lead to an increase of unnatural ways of conception through assisted reproduction techniques in the specialised centres. Natural estrogens are one of these compounds and they get into waste water after being excluded from the body by the urine. They get back into the human body from drinking water or from the food, and they can interfere with function of endogenous hormones in very low concentrations. For these reasons it is up to date to deal with the influence of these compounds on mammalian sperm. For many years, estrogens have been considered typically female sex hormones. It is now certain that they are also very important in the regulation of male reproduction. Endogenous estrogens in mammalian males are an important part of the endocrine system. Estrogens play an important role in the development of germ cells, spermatogenesis and processes leading to successful egg fertilization such as a capacitation or acrosomal reaction. Tyrosine phosphorylation is one of the essential steps for the properly ongoing process of capacitation in sperm followed by a...
15

Estudo do efeito das condições de manipulação do sêmen de jaguatiricas (Leopardus pardalis, Linnaeus, 1758) sobre a capacitação e a integridade morfológica e funcional dos espermatozóides / Study of the effect of ocelot (Leopardus pardalis; Linnaeus, 1758) semen manipulation on capacitation and on morphological and functional integrity of spermatozoa

Queiroz, Vinicius de Seixas 28 November 2003 (has links)
O presente estudo visou investigar o efeito da refrigeração do sêmen da jaguatirica sobre o Índice de Motilidade Espermática [IME=(%M+MPx5)/2; %M = proporção de espermatozóides móveis; MP = motilidade progressiva], integridade acrossomal (IA) e capacitação espermática; assim como avaliar a eficácia da técnica FITC-PNA/IP na avaliação simultânea da viabilidade espermática (VE) e IA. Sete jaguatiricas foram eletroejaculadas, sendo utilizados apenas ejaculados (n=16) apresentando %M>=60% e MP>=3. Avaliou-se a IA por meio da Coloração Simples. Os ejaculados foram diluídos 1:1 na Variante do Diluente de PLatz e submetidos aos Protocolos de Transporte: Temperatura Ambiente e Refrigeração, - 0,23ºC/min, (Experimento 1); ou apenas Temperatura Ambiente (Experimentos 2 e 3). Após 2h, as alíquotas foram reaquecidas, reavaliando-se os parâmetros observados antes do transporte. Os espermatozóides foram lavados por centrifugação em meio F10 de Ham, ressuspensos nesse meio e processados conforme o experimento: (1) após pré-incubação (38ºC; 5%CO2) durante 0, 1, 2 e 4 horas, foram retiradas alíquotas a cada intervalo para serem incubadas (30 min) na ausência e na presença do cálcio ionóforo A23187 (Ca2+Ion) (1mM), avaliando-se IA e IME; (2) após pré-incubação por 0, 1 e 2h, foram incubadas alíquotas na ausência e presença de 1 e 2mM de Ca2+Ion, avaliado-se IA e IME; (3) pré-incubados por 9h, sendo retiradas alíquotas a cada hora, para as avaliações da IA e VE, (a) separadamente através da Coloração Simples e do IME, ou (b) simultaneamente através da técnica FITC-PNA/IP. A refrigeração causou declínio (p<0,02) da IA (71,0%) e IME (67,1), em comparação aos valores observados antes do transporte (88,5%; 85,4), enquanto a manutenção das amostras à temperatura ambiente não afetou (p>0,1) essas variáveis (84,8%; 76,4). Dentre as amostras refrigeradas, aquelas expostas ao Ca2+Ion sofreram redução (p<0,01) na IA (52,4%) frente ao controle (55,56%). Já nas amostras transportadas à temperatura ambiente, não foi observada diferença (p>0,1) entre os grupos com e sem ionóforo (64,41% vs. 63,87%). Quando analisados os tempos separadamente, o único tratamento em que houve efeito (p<0,05) do Ca2+Ion sobre a IA foi aquele refrigerado e pré-incubado por 2h. Foi verificada redução (p<0,05) nos valores de IME e IA devida à simples incubação, mesmo na ausência do Ca2+Ion. A concentração de 2µM dessa substância foi mais efetiva na indução da reação acrossômica que 1µM. Apesar dos fluorocromos FITC-PNA/IP terem se ligado aos espermatozóides, nas regiões esperadas, a proporção de células marcadas variou aleatoriamente durante pré-incubação, sem correlação (p>0,1) com IME. A IA avaliada pela Coloração Simples apresentou correlação positiva (r=0,77; p<0,0001) com IME, decrescendo (p<0,0001) durante pré-incubação. A refrigeração mostrou-se desvantajosa frente à manutenção do sêmen à temperatura ambiente, pois foi deletéria à função e às membranas dos espermatozóides. A refrigeração tornou-os capazes de responder ao estímulo do Ca2+Ion, característica observada nos espermatozóides capacitados. O ensaio de reação acrossômica induzida pelo Ca2+Ion deve ser aperfeiçoado para permitir avaliação acurada da capacitação espermática na jaguatirica. A Coloração Simples associada à avaliação do IME foi mais eficiente e menos laboriosa, frente á técnica FITC-PNA/IP, na avaliação da IA e VE. / This study aimed to investigate the effect of ocelot semen refrigeration on Sperm Motility Index [SMI=(%M+PMx5)/2; %M = proportion of motile spermatozoa ; PM = Progressive Motility], acrossomal integrity (AI) and sperm capacitation. Another objective was to evaluate the FITC-PNA/IP technique efficacy on evaluating simultaneously sperm viability (SV) and AI. Five ocelots, were electroejaculated, the semen was evaluated and only ejaculates (n=16) presenting %M>=60% and PM>=3 were used. Sperm AI was evaluated using Fast Green / Rose Bengal staining (FGRB). The ejaculates were diluted 1:1 in Platz Diluent Variant and subjected to the transportation protocols: Room Temperature and Cooling, -0.23ºC/min, (experiment 1); or only Room Temperature (experiments 2 and 3). After 2 hours, the aliquots were rewarmed and samples were taken to re-evaluate the parameters observed before the transport. The spermatozoa were washed in Ham’s F10 medium, ressuspended in fresh medium and processed differently, according the experiment: (1) after pre-incubation (38ºC; 5%CO2) during 0, 1, 2 and 4 hours, samples were taken at each time point to be incubated in the absence and presence of 1mM calcium ionophore A23187 (Ca2+Ion), SMI and AI were evaluated; (2) after pre-incubation during 0, 1 and 2h, aliquots were incubated in the absence and presence of 1 and 2 mM Ca2+Ion; SMI and AI were evaluated; (3) after pre-incubation during 9h, aliquots were taken every hour to compare the evaluation of SV and AI (a) separately by the FGRB staining and SMI or (b) simultaneously by the FITC-PNA / IP technique. Cooling caused decline (p<0.02) on AI (71.0%) and SMI (67.1), when compared to values observed before transportation (88.5%; 85.4). Maintenance at room temperature didn’t affect (p>0.1) these variables (84.8%; 76.4). Among cooled samples, spermatozoa exposed to Ca2+Ion showed smaller (P<0.01) AI value (52.4%) compared to the group incubated without that substance (55.56%). For samples transported at room temperature, it wasn’t observed difference (P>0.05) between the groups with and without ionophore (64.41% vs. 63.87%). When time intervals were analysed separately, the only treatment in which there was effect (p<0,05) of Ca2+Ion on AI was the group refrigerated and pre-incubated for 2h. There was a reduction (p<0,05) on SMI and AI due simply to incubation, even in the absence of Ca2+Ion. The 2µM concentration of this substance was more effective to induce acrosome reaction than 1µM. FITC-PNA and IP fluorocromes bound spermatozoa at the expected sites. However, proportion of marked cells varied randomly during pre-incubation, and didn’t correlate (p>0,1) with SMI. IA evaluated by FGRB staining showed positive correlation (r=0,77; p<0,0001) with SMI, decreasing (p<0,0001) during incubation. Cooling was disadvantageous compared to maintaining semen at room temperature, since it was deleterious to spermatozoa membranes and function, and made those cells capable to answer the Ca2+Ion challenge, a characteristic observed in capacitated spermatozoa. Ca2+Ion induced acrosome reaction assay must be improved to allow accurate evaluation of sperm capacitation on ocelots. FGRB staining associated to SMI evaluation was more efficient and easier to perform, than FITC-PNA/IP technique, for AI and SV investigation.
16

Estudo das alterações morfo-funcionais de espermatozóides bovinos submetidos à sexagem por meio da técnica de citometria de fluxo / Study of morpho-functions alterations in bovine spermatozoa submitted on sorting through flow cytometry technology

Tanno, Priscilla Harumi 14 September 2009 (has links)
O objetivo deste estudo foi avaliar as alterações morfo-funcionais do sêmen bovino submetido à sexagem através da técnica de citometria de fluxo e comparar com o sêmen convencional e a diferença entre as subespécies. O sêmen foi obtido de seis touros, sendo três taurinos (Holandês preto e branco) e três zebuínos (Gir leiteiro), com quatro ejaculados de cada animal (n = 24). Cinco tratamentos foram realizados: sêmen convencional com diluidor L (Lagoa); sêmen convencional com diluidor S (Sexing) e sêmen sexado (nos tempos de zero, três e seis horas após a ejaculação para avaliar se existem alterações de membranas ao longo do tempo). Foram avaliados pela citometria de fluxo quanto à integridade de membrana plasmática e reação acrossomal (PI/FITC-PSA); peroxidação lipídica (C11-BODIPY581/591) e capacitação espermática através de análises da fosforilação da tirosina e aumento da fluidez e desorganização da membrana plasmática (Merocianina 540 e Yo-Pro1). Os efeitos de tratamentos foram avaliados por análises de variância (ANOVA), empregando-se o programa estatístico Stat-View&reg; (SAS Institute, Inc. 1998, Cary, NC, USA). Foram considerados significativos os valores com P<0,05 e com tendência a significância (P<0,10). O sêmen proveniente da subespécie taurina teve um efeito negativo mais significante do que a zebuína na qualidade do sêmen. O sêmen sexado apresentou maior peroxidação lipídica nos espermatozóides com membrana íntegra e a presença de proteínas fosforiladas na superfície da membrana plasmática, fatores que são indicativos de capacitação espermática. Porém, ao contrário do esperado, este aumento não foi acompanhado pela quantidade de células classificadas como capacitadas pela análise de associação de sondas Yo-Pro-1 e Merocianina 540, pois o sêmen convencional apresentou maior população espermática com membrana plasmática íntegra desorganizada (P<0,05). Não houve piora na qualidade do sêmen sexado devido ao tempo de espera do ejaculado (P<0,05). / The objective of this study was to evaluate the morpho-functions alterations in bovine semen submitted on sorting through flow cytometry technology and compare with conventional semen and the difference between the subspecies. Semen was obtained from six bulls, that three were taurine (Holstein Black and White) and three were zebuine (Dairy Gir) with four ejaculates from each animal (n = 24). Five treatments were performed: conventional semen with L (Lagoa) media; conventional semen with S (Sexing) media and sexed semen (zero, three and six hours after ejaculation to evaluate if there were membrane alterations over the time). The treatments were analyzed with flow cytometry as for plasmatic membrane integrity and acrosome reaction (PI/FITC-PSA); lipid peroxidation (C11-BODIPY581/591) and sperm capacitation through protein tyrosine phosphorylation and the increase in plasma membrane fluidity and disorganization (Merocyanine 540 and Yo-Pro-1). The treatments effects were evaluated by analysis of variance (ANOVA) (Stat-View&reg; SAS Institute, Inc. 1998, Cary, NC, USA). Effects were considered significant if the values were P<0.05 and with significant tendency (P<0.10). Semen from the taurine subspecie had a more significant negative effect than zebuine on semen quality. Sexed semen showed more lipid peroxidation in sperm with membrane integrity and the presence of phosphorylated proteins in plasma membrane surface that seemed to be sperm capacitation. However, in the contrary of expected, this increase did not accompany with quantity of cells classified as capacitated by the association probes Yo-Pro-1 e Merocyanine 540 analyse because the conventional semen showed more sperm population with plasma membrane integrity disorganized (P<0.05). There was not worsening in sexed semen quality over the time ejaculate waiting (P<0.05).
17

Les phospholipases A2 au cours de la fécondation et du développement embryonnaire préimplantatoire : mécanismes moléculaires d'action et développement thérapeutique / Phospholipases A2 during fertilization : molecular mechanisms of action and therapeutic development

Abi Nahed, Roland 24 June 2015 (has links)
La dégradation des fonctions de reproduction masculine dans les dernières décennies, et par suite, la baisse du taux de fertilité chez l'homme a renforcé les démarches de recherche des causes d'infertilité masculine, qu'elles soient génétiques, ou environnementales, mettant en œuvre les perturbateurs endocriniens ou d'autres produits reprotoxiques. Par ailleurs, les traitements palliatifs tels que l'aide médicale à la procréation ne permettent qu'à 1 couple sur deux d'obtenir une grossesse. La recherche vise donc également à définir de nouvelles pistes d'amélioration de ces techniques. Les phospholipases A2 (PLA2) sont des enzymes abondamment exprimées dans les organes reproducteurs mâles, le sperme éjaculé et dans le tractus génital femelle. Elles jouent des rôles importants dans la capacitation, la réaction acrosomique (RA) et la fécondation. Nous avons montré au laboratoire que la PLA2 murine secrétée de groupe X (mGX) est présente dans l'acrosome des spermatozoïdes de souris. Elle est libérée au cours de la RA et s'avère un inducteur puissant de la RA. Les mécanismes permettant ces effets sont encore mal connus. Par l'utilisation d'inducteurs et d'inhibiteurs des PLA2, sur des modèles murins wild type ou KO pour certaines PLA2, ce travail montre que durant la capacitation, l'activation des iPLA2 β permet de déclencher une RA spontanée dans une sous-population spécifique de spermatozoïdes. Au cours de la RA induite par la progestérone (P4), On a pu aussi valoriser le rôle des iPLA2 β qui initie la cascade de la RA et permet que les sPLA2 soient activées pour amplifier le déroulement de la réaction acrosomique. Par ailleurs, ce travail montre que l'effet de mGX sur le taux de fécondation et de développement embryonnaire ne dépend pas du taux de la RA. Cet effet obtenu grâce à mGX n'est pas observé avec d'autres sPLA2 (murine ou humaine), ni avec la P4 ce qui lui confère une propriété espèce dépendante. / For the last ten years, the impairment of the male reproductive functions has highly increased, while the use of assisted reproductive techniques has also increased. Despite this evolution, the pregnancy rates obtained in in vitro fertilization (IVF) remain low, as only one in two couples will obtain a pregnancy after 4 attempts. Research has to discover new ways to gain in reproductive impact. Hence, many studies have recently been developed to test molecules that could improve the IVF results. Phospholipases A2 (PLA2s) are part of these molecules. They play an important role, because of their abundant expression in: male reproductive organs, in ejaculated sperm and in the female tract. Several studies have suggested a role for members of the secreted phospholipase A2 family in capacitation, acrosome reaction (AR), and fertilization. We demonstrated previously that sperm from mGX knock-out mice had a severely impaired fertilization potential in vitro, but the molecular nature of these enzymes and their specific functions have remained elusive. Our aims were to study the mechanism of the acrosome reaction by focusing on different kinds of PLA2 using inhibitors and knockout mice for each type of PLA2. We demonstrate the importance of iPLA2β in spontaneous AR occurring during capacitation. We also show that iPLA2β and sPLA2 of group X are both involved in progesterone (P4)-induced AR in mouse sperm. In addition we show that in the mouse neither P4 nor any of the other sPLA2s tested are able to mimic the IVF improvement obtained with mGX-treatment. We also demonstrate that this improvement obtained with phospholipase A2 murine group X is not dependent on the rate of AR. These results demonstrate that sPLA2s are not commutable in the context of mouse sperm fertility, indicating that group X sPLA2 is unique to improve fertility outcome.
18

Estudo das alterações morfo-funcionais de espermatozóides bovinos submetidos à sexagem por meio da técnica de citometria de fluxo / Study of morpho-functions alterations in bovine spermatozoa submitted on sorting through flow cytometry technology

Priscilla Harumi Tanno 14 September 2009 (has links)
O objetivo deste estudo foi avaliar as alterações morfo-funcionais do sêmen bovino submetido à sexagem através da técnica de citometria de fluxo e comparar com o sêmen convencional e a diferença entre as subespécies. O sêmen foi obtido de seis touros, sendo três taurinos (Holandês preto e branco) e três zebuínos (Gir leiteiro), com quatro ejaculados de cada animal (n = 24). Cinco tratamentos foram realizados: sêmen convencional com diluidor L (Lagoa); sêmen convencional com diluidor S (Sexing) e sêmen sexado (nos tempos de zero, três e seis horas após a ejaculação para avaliar se existem alterações de membranas ao longo do tempo). Foram avaliados pela citometria de fluxo quanto à integridade de membrana plasmática e reação acrossomal (PI/FITC-PSA); peroxidação lipídica (C11-BODIPY581/591) e capacitação espermática através de análises da fosforilação da tirosina e aumento da fluidez e desorganização da membrana plasmática (Merocianina 540 e Yo-Pro1). Os efeitos de tratamentos foram avaliados por análises de variância (ANOVA), empregando-se o programa estatístico Stat-View&reg; (SAS Institute, Inc. 1998, Cary, NC, USA). Foram considerados significativos os valores com P<0,05 e com tendência a significância (P<0,10). O sêmen proveniente da subespécie taurina teve um efeito negativo mais significante do que a zebuína na qualidade do sêmen. O sêmen sexado apresentou maior peroxidação lipídica nos espermatozóides com membrana íntegra e a presença de proteínas fosforiladas na superfície da membrana plasmática, fatores que são indicativos de capacitação espermática. Porém, ao contrário do esperado, este aumento não foi acompanhado pela quantidade de células classificadas como capacitadas pela análise de associação de sondas Yo-Pro-1 e Merocianina 540, pois o sêmen convencional apresentou maior população espermática com membrana plasmática íntegra desorganizada (P<0,05). Não houve piora na qualidade do sêmen sexado devido ao tempo de espera do ejaculado (P<0,05). / The objective of this study was to evaluate the morpho-functions alterations in bovine semen submitted on sorting through flow cytometry technology and compare with conventional semen and the difference between the subspecies. Semen was obtained from six bulls, that three were taurine (Holstein Black and White) and three were zebuine (Dairy Gir) with four ejaculates from each animal (n = 24). Five treatments were performed: conventional semen with L (Lagoa) media; conventional semen with S (Sexing) media and sexed semen (zero, three and six hours after ejaculation to evaluate if there were membrane alterations over the time). The treatments were analyzed with flow cytometry as for plasmatic membrane integrity and acrosome reaction (PI/FITC-PSA); lipid peroxidation (C11-BODIPY581/591) and sperm capacitation through protein tyrosine phosphorylation and the increase in plasma membrane fluidity and disorganization (Merocyanine 540 and Yo-Pro-1). The treatments effects were evaluated by analysis of variance (ANOVA) (Stat-View&reg; SAS Institute, Inc. 1998, Cary, NC, USA). Effects were considered significant if the values were P<0.05 and with significant tendency (P<0.10). Semen from the taurine subspecie had a more significant negative effect than zebuine on semen quality. Sexed semen showed more lipid peroxidation in sperm with membrane integrity and the presence of phosphorylated proteins in plasma membrane surface that seemed to be sperm capacitation. However, in the contrary of expected, this increase did not accompany with quantity of cells classified as capacitated by the association probes Yo-Pro-1 e Merocyanine 540 analyse because the conventional semen showed more sperm population with plasma membrane integrity disorganized (P<0.05). There was not worsening in sexed semen quality over the time ejaculate waiting (P<0.05).
19

Estudo do efeito das condições de manipulação do sêmen de jaguatiricas (Leopardus pardalis, Linnaeus, 1758) sobre a capacitação e a integridade morfológica e funcional dos espermatozóides / Study of the effect of ocelot (Leopardus pardalis; Linnaeus, 1758) semen manipulation on capacitation and on morphological and functional integrity of spermatozoa

Vinicius de Seixas Queiroz 28 November 2003 (has links)
O presente estudo visou investigar o efeito da refrigeração do sêmen da jaguatirica sobre o Índice de Motilidade Espermática [IME=(%M+MPx5)/2; %M = proporção de espermatozóides móveis; MP = motilidade progressiva], integridade acrossomal (IA) e capacitação espermática; assim como avaliar a eficácia da técnica FITC-PNA/IP na avaliação simultânea da viabilidade espermática (VE) e IA. Sete jaguatiricas foram eletroejaculadas, sendo utilizados apenas ejaculados (n=16) apresentando %M>=60% e MP>=3. Avaliou-se a IA por meio da Coloração Simples. Os ejaculados foram diluídos 1:1 na Variante do Diluente de PLatz e submetidos aos Protocolos de Transporte: Temperatura Ambiente e Refrigeração, - 0,23ºC/min, (Experimento 1); ou apenas Temperatura Ambiente (Experimentos 2 e 3). Após 2h, as alíquotas foram reaquecidas, reavaliando-se os parâmetros observados antes do transporte. Os espermatozóides foram lavados por centrifugação em meio F10 de Ham, ressuspensos nesse meio e processados conforme o experimento: (1) após pré-incubação (38ºC; 5%CO2) durante 0, 1, 2 e 4 horas, foram retiradas alíquotas a cada intervalo para serem incubadas (30 min) na ausência e na presença do cálcio ionóforo A23187 (Ca2+Ion) (1mM), avaliando-se IA e IME; (2) após pré-incubação por 0, 1 e 2h, foram incubadas alíquotas na ausência e presença de 1 e 2mM de Ca2+Ion, avaliado-se IA e IME; (3) pré-incubados por 9h, sendo retiradas alíquotas a cada hora, para as avaliações da IA e VE, (a) separadamente através da Coloração Simples e do IME, ou (b) simultaneamente através da técnica FITC-PNA/IP. A refrigeração causou declínio (p<0,02) da IA (71,0%) e IME (67,1), em comparação aos valores observados antes do transporte (88,5%; 85,4), enquanto a manutenção das amostras à temperatura ambiente não afetou (p>0,1) essas variáveis (84,8%; 76,4). Dentre as amostras refrigeradas, aquelas expostas ao Ca2+Ion sofreram redução (p<0,01) na IA (52,4%) frente ao controle (55,56%). Já nas amostras transportadas à temperatura ambiente, não foi observada diferença (p>0,1) entre os grupos com e sem ionóforo (64,41% vs. 63,87%). Quando analisados os tempos separadamente, o único tratamento em que houve efeito (p<0,05) do Ca2+Ion sobre a IA foi aquele refrigerado e pré-incubado por 2h. Foi verificada redução (p<0,05) nos valores de IME e IA devida à simples incubação, mesmo na ausência do Ca2+Ion. A concentração de 2µM dessa substância foi mais efetiva na indução da reação acrossômica que 1µM. Apesar dos fluorocromos FITC-PNA/IP terem se ligado aos espermatozóides, nas regiões esperadas, a proporção de células marcadas variou aleatoriamente durante pré-incubação, sem correlação (p>0,1) com IME. A IA avaliada pela Coloração Simples apresentou correlação positiva (r=0,77; p<0,0001) com IME, decrescendo (p<0,0001) durante pré-incubação. A refrigeração mostrou-se desvantajosa frente à manutenção do sêmen à temperatura ambiente, pois foi deletéria à função e às membranas dos espermatozóides. A refrigeração tornou-os capazes de responder ao estímulo do Ca2+Ion, característica observada nos espermatozóides capacitados. O ensaio de reação acrossômica induzida pelo Ca2+Ion deve ser aperfeiçoado para permitir avaliação acurada da capacitação espermática na jaguatirica. A Coloração Simples associada à avaliação do IME foi mais eficiente e menos laboriosa, frente á técnica FITC-PNA/IP, na avaliação da IA e VE. / This study aimed to investigate the effect of ocelot semen refrigeration on Sperm Motility Index [SMI=(%M+PMx5)/2; %M = proportion of motile spermatozoa ; PM = Progressive Motility], acrossomal integrity (AI) and sperm capacitation. Another objective was to evaluate the FITC-PNA/IP technique efficacy on evaluating simultaneously sperm viability (SV) and AI. Five ocelots, were electroejaculated, the semen was evaluated and only ejaculates (n=16) presenting %M>=60% and PM>=3 were used. Sperm AI was evaluated using Fast Green / Rose Bengal staining (FGRB). The ejaculates were diluted 1:1 in Platz Diluent Variant and subjected to the transportation protocols: Room Temperature and Cooling, -0.23ºC/min, (experiment 1); or only Room Temperature (experiments 2 and 3). After 2 hours, the aliquots were rewarmed and samples were taken to re-evaluate the parameters observed before the transport. The spermatozoa were washed in Ham’s F10 medium, ressuspended in fresh medium and processed differently, according the experiment: (1) after pre-incubation (38ºC; 5%CO2) during 0, 1, 2 and 4 hours, samples were taken at each time point to be incubated in the absence and presence of 1mM calcium ionophore A23187 (Ca2+Ion), SMI and AI were evaluated; (2) after pre-incubation during 0, 1 and 2h, aliquots were incubated in the absence and presence of 1 and 2 mM Ca2+Ion; SMI and AI were evaluated; (3) after pre-incubation during 9h, aliquots were taken every hour to compare the evaluation of SV and AI (a) separately by the FGRB staining and SMI or (b) simultaneously by the FITC-PNA / IP technique. Cooling caused decline (p<0.02) on AI (71.0%) and SMI (67.1), when compared to values observed before transportation (88.5%; 85.4). Maintenance at room temperature didn’t affect (p>0.1) these variables (84.8%; 76.4). Among cooled samples, spermatozoa exposed to Ca2+Ion showed smaller (P<0.01) AI value (52.4%) compared to the group incubated without that substance (55.56%). For samples transported at room temperature, it wasn’t observed difference (P>0.05) between the groups with and without ionophore (64.41% vs. 63.87%). When time intervals were analysed separately, the only treatment in which there was effect (p<0,05) of Ca2+Ion on AI was the group refrigerated and pre-incubated for 2h. There was a reduction (p<0,05) on SMI and AI due simply to incubation, even in the absence of Ca2+Ion. The 2µM concentration of this substance was more effective to induce acrosome reaction than 1µM. FITC-PNA and IP fluorocromes bound spermatozoa at the expected sites. However, proportion of marked cells varied randomly during pre-incubation, and didn’t correlate (p>0,1) with SMI. IA evaluated by FGRB staining showed positive correlation (r=0,77; p<0,0001) with SMI, decreasing (p<0,0001) during incubation. Cooling was disadvantageous compared to maintaining semen at room temperature, since it was deleterious to spermatozoa membranes and function, and made those cells capable to answer the Ca2+Ion challenge, a characteristic observed in capacitated spermatozoa. Ca2+Ion induced acrosome reaction assay must be improved to allow accurate evaluation of sperm capacitation on ocelots. FGRB staining associated to SMI evaluation was more efficient and easier to perform, than FITC-PNA/IP technique, for AI and SV investigation.
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Levonorgestrel como contraceptivo de emergência e sua influência sobre algumas funções espermáticas / Levonorgestrel as emergency contraceptive and its influence upon some sperm functions

Hermanny, Alexia, 1965- 12 February 2011 (has links)
Orientador: Luis Guillermo Bahamondes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T05:07:00Z (GMT). No. of bitstreams: 1 Hermanny_Alexia_D.pdf: 843759 bytes, checksum: 4b2ff42ff4ef1f995e85e5f8b86bf7f2 (MD5) Previous issue date: 2011 / Resumo: O mecanismo de ação do levonorgestrel (LNG) na anticoncepção de emergência (AE) ainda não está totalmente esclarecido e seu efeito nas funções espermáticas também não está explicado. Os objetivos deste trabalho foram avaliar se o LNG, em dose igual à observada após a ingestão oral para AE, poderia afetar espermatozoides expostos in vitro à tuba uterina humana e realizar uma revisão bibliográfica sobre o efeito do LNG nas diferentes funções espermáticas. Foram realizados 15 experimentos. As tubas uterinas foram removidas através de mini-laparotomias e foram perfundidas com uma suspensão contendo 1x106 espermatozoides móveis, com e sem LNG. A tuba correspondente ao lado onde o folículo dominante estava presente recebeu a suspensão com LNG em pacientes alternados. Após um período de incubação de 4 horas, o istmo e a ampola de cada tuba foram separados. Cada segmento foi lavado separadamente e o material obtido foi avaliado quanto ao número de espermatozoides móveis recuperados, número de espermatozoides aderidos ao epitélio tubário e taxa de reação acrossômica (RA). A presença do LNG não afetou significativamente o número de espermatozoides móveis recuperados do istmo e da ampola, e não afetou o número de espermatozoides aderidos ao epitélio tubário. O LNG também não influenciou a taxa de RA. Diferenças significativas também não foram observadas quando o lado ovulatório foi considerado. A revisão bibliográfica realizada deixou evidente que existem poucos estudos que analisam a influência do LNG como AE sobre as funções espermáticas, apesar de este ser um possível mecanismo de ação. Além disso, os estudos revisados utilizam diferentes métodos de avaliação e os resultados são, muitas vezes, contraditórios. De acordo com os resultados observados na literatura, quando o LNG é usado na AE, provavelmente não atinge concentração plasmática suficiente para ser reconhecido pelos receptores de progesterona (P). Resultados positivos só foram observados quando a dose de LNG utilizada nos experimentos foi comparável ao sistema intrauterino liberador de LNG (SIU-LNG), ou seja, muito maior que a utilizada na AE. O LNG, em dose similar à observada no plasma após a ingestão oral para AE, não afetou o número, a aderência ao epitélio tubário, a distribuição e a taxa de RA de espermatozoides na tuba uterina humana, in vitro. De acordo com os resultados observados na literatura, se o LNG, na concentração utilizada para AE, afeta ou não a função espermática ainda não está claro, e mais estudos são necessários / Abstract: The mechanism of action of levonorgestrel (LNG) as emergency contraception (EC) is still under debate and the effect upon sperm function is partially explained. The aim of this study was to assess if LNG in a similar dose to those observed in serum after oral intake for EC could affect the spermatozoa when exposed in vitro to human tubes and also to give an overview of the effect of LNG as EC on several sperm functions. Fifteen mini-laparotomies were performed, the ovulatory side was recorded and both tubes were removed and perfused with a suspension of 1x106 of motile spermatozoa, one with LNG and the other without it. After an incubation period of 4hours the tubes were cut to separate the isthmus and the ampulla. Each segment was flushed and the material was evaluated regarding the motile sperm number, the number of spermatozoa adhering to the oviductal epithelium and acrosome reaction (AR) rate. The addition of LNG did not significantly affect the number of recovered spermatozoa neither at the isthmus nor at the ampulla or the number of recovered spermatozoa adhered at the human tubal epithelium. Additionally, LNG did not influence the rate of AR. There were no significant differences even when the ovulatory side was taken into account. The present review showed that there are few studies which focus on the influence of LNG as EC upon sperm functions; albeit it is a plausible mechanism of action. Additionally, the different studies used different methods of evaluation and the results were in many cases contradictories. According to the results observed at the literature, when LNG is used as EC, it is probable that the drug does not achieved sufficient serum concentrations in order to be recognized by the progesterone (P) receptors. Positive results only were observed when the dose of LNG used in the experiments was much higher (comparable to the LNG-IUS) than the proposed for EC. LNG in a similar dose to that observed in serum after oral intake for EC did not affect the number, the adhesion to tubal epithelium, distribution, and AR rate of spermatozoa at the human Fallopian tubes in vitro. According to the results observed at the literature, if the LNG in doses used for EC, affects sperm function or not, it is still uncertain and warrants further studies / Doutorado / Fisiopatologia Ginecológica / Doutor em Ciências da Saúde

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