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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.
1

Spermatological characters in Bothriocephalidea (Cestoda) / Spermatological characters in Bothriocephalidea (Cestoda)

ŠÍPKOVÁ, Lenka January 2011 (has links)
Spermiogenesis and ultrastructure of the spermatozoon of two bothriocephalidean cestodes, Oncodiscus sauridae and Senga sp., have been studied using transmission electron microscopy. The presence of a classical pattern for spermatological characters (spermiogenesis of type I with dense-material in early stages and sperm of type II with a characteristic ring of cortical microtubules in the anterior part) in Bothriocephalidea is discussed.
2

Liens entre la morphologie et les marques épigénétiques, la qualité de l'ADN, le contenu chromosomique et les capacités fécondantes du spermatozoïde humain / How to link human sperm morphology to its epigenetic status, DNA integrity, chromosome content and fecundity ?

Boitrelle, Florence 27 June 2014 (has links)
Les qualités intrinsèques spermatiques (état de condensation de la chromatine, intégrité de l’ADN, contenu chromosomique, capacités fécondantes..) sont très variables d’un spermatozoïde à l’autre. Le pari aujourd’hui en assistance médicale à la procréation est de relier un aspect morphologique spermatique à ces qualités intrinsèques dans le but de mieux choisir le spermatozoïde vivant à injecter et d’améliorer les taux de grossesse. Depuis 2002, le MSOME (Motile Sperm Organelle Morphology Examination) permet d’observer les spermatozoïdes à fort grossissement, en contraste interférentiel de Nomarski et d’observer des structures qu’on appelle les « vacuoles ». L’injection intra-ovocytaire de spermatozoïdes sélectionnés en MSOME (IMSI) comme non porteurs de vacuoles céphaliques permettrait d’améliorer les taux de grossesses évolutives. Ici, nous avons montré que les vacuoles spermatiques correspondaient à des cratères nucléaires en lien avec une non-condensation chromatinienne (non remplacement des histones au cours de la spermiogenèse). Certaines atypies morphologiques spermatiques sont aussi en lien avec une non-condensation de la chromatine. De plus, spermatozoïdes vacuolés présentent parfois des taux de fragmentation élevés. Aucun lien n’a cependant été retrouvé entre un aspect morphologique spermatique d’une part et un contenu chromosomique ou des capacités fécondantes particulières d’autre part. De ces liens, nous avons pu dégager de nouvelles indications d’IMSI. Ainsi, nous avons avancé dans la description des critères de sélection du spermatozoïde humain vivant donnant le moins de risque d’échec d’implantation embryonnaire et/ou d’anomalies pour la descendance / Intrinsic sperm quality criteria (chromatin condensation, DNA fragmentation, chromosome content, fecundity, etc.) vary from one spermatozoon to another. It is critical to be able to link morphological aspects to these quality criteria, in order to improve the selection of high-quality, live spermatozoa and thus improve pregnancy and delivery rates. Since 2002, motile sperm organelle morphology examination has been used to screen for defects under high magnification and thus select vacuole-free spermatozoa (which are known to be associated with higher pregnancy rates in intracytoplasmic morphologically selected sperm injection (IMSI) programmes). Here, we demonstrate that sperm vacuoles are nuclear concavities associated with chromatin condensation failure (due to a lack of histone replacement during spermiogenesis). A number of other morphological abnormalities were found to be linked to chromatin condensation failure. In some cases, vacuolated spermatozoa were seen to be more DNA-fragmented than vacuole-free ones. In contrast, sperm morphology was not related to chromosomal content or fecundity characteristics. Our observations enabled us to identify new indications for IMSI and refine the criteria for selecting the best spermatozoon: the spermatozoon with the lowest risk of implantation failure or abnormalities in the offspring
3

Ciclo reprodutivo e análise ultraestrutural da espermatogênese de Cichla kelberi (TeLeostei: Perciformes: Cichlidae)

Silva, Diógenes Henrique de Siqueira [UNESP] 25 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T19:49:20Z : No. of bitstreams: 1 silva_dhs_me_sjrp.pdf: 1621876 bytes, checksum: e4bf3e0e11a59ba7cb6ff705065a880c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Cichla kelberi, espécie recentemente classificada e popularmente conhecida como tucunaré amarelo, é endêmico dos rios Araguaia e baixo Tocantins, sendo, entretanto, encontrado em muitas outras bacias, onde apresenta grande importância para a pesca profissional por seu alto valor econômico, devido a qualidade e sabor de sua carne, e pela pesca esportiva, como pode ser observado pelos campeonatos anuais de pesca ao tucunaré nos rios em que se encontra. Para entender esse rápido processo de ocupação e adaptação a novos ambientes, 78 exemplares de Cichla kelberi foram mensalmente coletados entre os meses de março de 2009 a fevereiro de 2010, com o auxílio de vara de pesca e anzol na Lagoa do Pernilongo (20º 29’ 11,93”S, 51º 25’ 33,27”O) e Ilha da Ferradura (20º 28’ 27,11” S, 51º 25’ 54,53”O), no Reservatório de Jupiá, rio Paraná, Ilha Solteira, São Paulo, Brasil, onde foi introduzido. Foram definidas quatro classes de maturação gonadal para o ciclo reprodutivo anual do tucunaré amarelo C. kelberi. A definição das classes de Maturação Inicial, Maturação Intermediária, Maturação Final e Regressão, tiveram como base as alterações do epitélio germinativo testicular associado aos estágios das células germinativas presentes. A Classe de Maturação Inicial é caracterizada pela presença de um epitélio germinativo totalmente contínuo, cistos com células germinativas em todos os estágios de desenvolvimento, intensa atividade espermatogênica por todo o testículo e raros “clusters” periféricos, formados por espermatogônias primárias. A Classe de Maturação Intermediária inicia com o surgimento de um epitélio germinativo descontínuo na região anastomosada, com diminuição da espermatogênese e estocagem de espermatozóides nesta região. Os agrupamentos periféricos de espermatogônias ou “clusters” estão ausentes... / The Cichla kelberi, a recently classified specie and popularly known as yellow peacock bass, is endemic from the Araguaia an low Tocantins river, being, however, found in many other basins, where has great importance for the professional fishing for its high economic value due to the quality and flavor of their meat and fishing, as can be observed by annual championships of peacock in the rivers where it is. To understand this fast process of occupation and adaptation to new environments, 78 specimens of C. kelberi were caught monthly between the months of March 2009 to February 2010 with the aid of fishing pole and hook, from the Lagoa do Pernilongo (20º 29’ 11,93”S, 51º 25’ 33,27”O) and Ilha da Ferradura (20º 28’ 27,11” S, 51º 25’ 54,53”O), in the Jupiá Reservoir, Parana River, Ilha Solteira, São Paulo, Brazil, where it was introduced. It was defined four gonadal maturation class to the annual reproductive cycle of the yellow peacock bass C. kelberi. The definition of the Early Maturation, Mid Maturation, Final Maturation and Regression Classes, were based on the changes of the testicular germinal epithelium associated with the germ cell stages present. The Class of Early Maturation is characterized by the presence of a fully continuous germinal epithelium, cysts with germ cells at all stages of development, intense spermatogenic activity throughout the testis and rare “clusters” peripherals, consisting of primary spermatogonia. The Mid maturation Class starts with the appearance of a discontinuous germinal epithelium in the anastomosed region with spermatogenesis decrease and sperm storage in this region. The peripheral groups of spermatogonia or clusters are missing at the end of this class of maturation. In the Final Maturation Class the germinal epithelium discontinuity reaches the periphery of lobules... (Complete abstract click electronic access below)
4

AVALIAÇÃO DA ENZIMA PARAOXONASE TIPO 1 NO PLASMA SEMINAL E SUA EXPRESSÃO DE RNAm DOS TECIDOS DAS GÔNADAS EM SUÍNOS / EVALUATION OF THE ENZYME PARAOXONASE TYPE 1 IN THE SEMINAL PLASMA AND ITS mRNA EXPRESSION IN BOARS GONADAL TISSUE

Lucca, Matheus Schardong 18 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The seminal plasma is particularly important in sperm protection against damage caused by reactive oxygen species (ROS). The paraoxonase type 1 (PON1) is a multi-enzymatic complex with antioxidant properties, preventing the increase of ROS quantities, thus protects cell membranes and neutralizes the effects of lipid oxidation. The objective of this study was to correlate the influence of PON1 activity with the CASA system parameters and sperm viability (membrane integrity acrosome integrity, functionality of mitochondria and DNA fragmentation) of swine semen in natura, and investigate the PON1 expression (mRNA) in testicle and epididymis (head, body and tail) tissue of boars. The sperm fraction (FE) presented the major PON1 activity and males 81, 80 and 79 (P<0.05) showed the highest enzyme activity. But, when comparing the differences between the ejaculate samples, our study showed differences (P<0.05) between males 81 and 92 in FE and sperm post fraction (PF). However, when the ejaculated was diluted (1:1), it has presented 44% average reduction in the activity of PON1. The activity of PON1 in FE showed positive correlation with sperm concentration, curvaceous distance, curvy velocity and DNA integrity (P<0.05), and also showed negative correlation with straightness and linearity parameters advised by the CASA system. The mRNA expression was observed only in the body portion of the epididymis. The FE is the part of the ejaculate that more PON1 activity and presented the parameters DCL, VCL, STR and LIN, together, with concentration and sperm viability (integrity of DNA) are those who showed the greatest association with the enzyme. Already the PON1 was only expressed (Mrna) in the body of epididymis pig breeder. / O plasma seminal é particularmente importante na proteção do espermatozoide contra os danos causados pelas espécies reativas ao oxigênio (EROs). A paraoxonase tipo 1 (PON1) é um complexo multienzimático com propriedades antioxidantes, impedindo o aumento da quantidade de EROs, o que confere proteção às membranas celulares e neutraliza os efeitos da oxidação lipídica. O estudo objetivou correlacionar a influência da atividade de PON1 com os parâmetros de avaliação do sistema Computer Assisted Semen Analysis (CASA) e a viabilidade espermática (integridade de membrana, integridade de acrossoma, funcionalidade de mitocôndria e fragmentação do DNA) do sêmen suíno in natura e investigar a expressão da PON1 (RNAm) no tecido do testículo e epidídimo (cabeça, corpo e cauda) do reprodutor suíno adulto. A fração espermática (FE) apresentou a maior atividade de PON1 e os machos 81, 80 e 79 (P<0,05) apresentaram a maior atividade de PON1. Já em relação a comparação entre as diferentes amostras do ejaculado, nosso estudo demonstrou diferenças (P<0,05) nos machos 81 e 92 em relação a FE e a fração pós-espermática (FP). Entretanto, quando o ejaculado foi diluído (1:1) apresentou redução média de 44% na atividade da PON1. A atividade de PON1 na FE apresentou uma correlação positiva com a concentração espermática, DCL, VCL e IDNA (P<0,05) e apresentou correlação negativa para os parâmetros de STR e LIN assessorados pelo sistema CASA. A expressão de RNAm somente foi observada para a porção do corpo do epidídimo. A FE é a parte do ejaculado que mais apresentou atividade da PON1 e os parâmetros DCL, VCL, STR e LIN, juntamente, com concentração e viabilidade espermática (integridade de DNA) são os que apresentaram a maior associação com a enzima. Já a PON1 foi somente expressa (RNAm) no corpo de epidídimo do reprodutor suíno.
5

Caractérisation du protéome du spermatozoïde humain / Caracterization of human sperm proteome

Jumeau, Fanny 16 September 2013 (has links)
La spermatogenèse est un processus complexe qui se déroule dans le tube séminifère du testicule. Au cours de ce processus, la cellule germinale entre en méiose puis réalise de profondes transformations cytologiques comme la compaction de la chromatine, la formation de l’acrosome et du flagelle. Les organites cytoplasmiques comme l’appareil de Golgi et le reticulum endoplasmique sont éliminés. Le spermatozoïde est alors une cellule organisée qui ne réalise pas ou peu de synthèse protéique. De plus, à la sortie du testicule, le spermatozoïde n’est pas mobile et incapable de féconder l’ovocyte. C’est par des interactions avec son environnement, l’épididyme et les voies génitales féminines, qu’il acquiert pleinement ces fonctions. Ces interactions se traduisent par des modifications du protéome comme le clivage des protéines ou des modifications post-traductionnelles. Ainsi, l’approche protéomique représente une méthode pertinente pour appréhender la physiologie spermatique. Toutefois, le protéome spermatique a fait l’objet de peu d’études et reste mal connu. Dans cette étude, le protéome du spermatozoïde humain a été réalisé selon deux approches. L’électrophorèse bidimensionnelle est particulièrement adaptée pour l’étude des modifications post-traductionnelles tandis que le shotgun constitue une technologie puissante en terme de sensibilité et d’identification des protéines. Les analyses bioinformatiques ont permis d’identifier les familles de protéines surexprimées de façon significative au sein du protéome spermatique. Parmi celles-ci, les protéines d’associations aux microtubules ont été sélectionnées en raison de leur rôle fondamental dans la dynamique du réseau microtubulaire et par conséquent, la mobilité spermatique. Le profil d’expression de la DCDC2C, une protéine de la famille des domaines à doublecortines, a été caractérisé dans le testicule et le spermatozoïde humain. De plus amples investigations sont nécessaires afin de préciser son rôle dans la physiologie spermatique.Outre la compréhension de processus physiologiques, les outils protéomiques permettent l’identification de nouveaux marqueurs de qualité du spermatozoïde. La caractérisation de la qualité spermatique repose actuellement sur un examen descriptif, le spermogramme-spermocytogramme, qui ne permet pas toujours d’expliquer l’infertilité du couple. Ainsi, l’amélioration des outils diagnostics et de la prise en charge de la fertilité sont les enjeux de la Procréation Médicalement Assistée. Dans ce contexte, nous avons observé le protéome de 161 échantillons de spermes normaux (OMS 2010). L’analyse de ce protéome a permis de définir un nouvel index de qualité protéique (SPQI) Les études statistiques ont montré que le SPQI est significativement associé à la mobilité progressive du spermatozoïde. Ainsi, le SPQI pourrait être un nouveau marqueur de qualité du spermatozoïde. Un kit permettant d’établir le SPQI en routine diagnostique est en cours de développement. / Spermatogenesis is a complex process located in seminiferous tubules of the testis. Germ cell underwent meiosis during the process following many cytological modifications such as chromatin compaction, biogenesis of both acrosome and flagellum. Subcellular components like the Golgi apparatus and endoplasmic reticulum were eliminated. Spermatozoa is then a highly organized cell which realized no or little de novo protein synthesis. Spermatozoa is furthermore unable to move and fertilize an oocyte outside of the testis, as it fully becomes functional by interacting with its environment, the epididymis and the female genital tracts. These interactions are translated by modifications of the proteome as proteins cleavage or post-translational modifications. The proteomic approach represents then a relevant method to understand sperm physiology. Nevertheless, few studies are related to sperm proteome which remains poorly known. This study has been conducted using two different approaches. 2D-electrophoresis is especially adapted to post-translational studies while the shotgun approach is a powerful and sensible tool for protein identification. Bioinformatic analyses helped identifying protein families overexpressed in a meaningful way inside the sperm proteome. Microtubules-associated proteins were among those that have been selected due to their role in the dynamic of microtubule network, thus in the sperm motility. The DCDC2C expression profile, a protein belonging to the doublecortin containing domain family, has been characterized in the testis and in the human spermatozoa. Further investigations are necessary in order to define its role in the sperm physiology.Besides the understanding of physiological processes, proteomic tools allow the identification of new markers of sperm quality. The characterization of sperm quality currently relies on a descriptive test that is not yet capable of explaining the infertility of a couple. Improving the diagnostic tool and management of fertility are the main objectives of reproductive studies. We have therefore observed the proteome of 161 normal sperm samples (WHO 2010). The proteome analysis defined a new sperm protein quality index (SPQI). Statistic studies show that this SPQI is significantly related to the progressive motility of the sperm. SPQI could then be used as a new quality marker of the spermatozoa. A kit that could help establishing SPQI routinely is currently in process.
6

Ciclo reprodutivo e análise ultraestrutural da espermatogênese de Cichla kelberi (TeLeostei: Perciformes: Cichlidae) /

Silva, Diógenes Henrique de Siqueira. January 2011 (has links)
Orientador: Carlos Alberto Vicentini / Banca: Classius de Oliveira / Banca: Sérgio Ricardo Batlouni / Resumo: O Cichla kelberi, espécie recentemente classificada e popularmente conhecida como tucunaré amarelo, é endêmico dos rios Araguaia e baixo Tocantins, sendo, entretanto, encontrado em muitas outras bacias, onde apresenta grande importância para a pesca profissional por seu alto valor econômico, devido a qualidade e sabor de sua carne, e pela pesca esportiva, como pode ser observado pelos campeonatos anuais de pesca ao tucunaré nos rios em que se encontra. Para entender esse rápido processo de ocupação e adaptação a novos ambientes, 78 exemplares de Cichla kelberi foram mensalmente coletados entre os meses de março de 2009 a fevereiro de 2010, com o auxílio de vara de pesca e anzol na Lagoa do Pernilongo (20º 29' 11,93"S, 51º 25' 33,27"O) e Ilha da Ferradura (20º 28' 27,11" S, 51º 25' 54,53"O), no Reservatório de Jupiá, rio Paraná, Ilha Solteira, São Paulo, Brasil, onde foi introduzido. Foram definidas quatro classes de maturação gonadal para o ciclo reprodutivo anual do tucunaré amarelo C. kelberi. A definição das classes de Maturação Inicial, Maturação Intermediária, Maturação Final e Regressão, tiveram como base as alterações do epitélio germinativo testicular associado aos estágios das células germinativas presentes. A Classe de Maturação Inicial é caracterizada pela presença de um epitélio germinativo totalmente contínuo, cistos com células germinativas em todos os estágios de desenvolvimento, intensa atividade espermatogênica por todo o testículo e raros "clusters" periféricos, formados por espermatogônias primárias. A Classe de Maturação Intermediária inicia com o surgimento de um epitélio germinativo descontínuo na região anastomosada, com diminuição da espermatogênese e estocagem de espermatozóides nesta região. Os agrupamentos periféricos de espermatogônias ou "clusters" estão ausentes... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Cichla kelberi, a recently classified specie and popularly known as yellow peacock bass, is endemic from the Araguaia an low Tocantins river, being, however, found in many other basins, where has great importance for the professional fishing for its high economic value due to the quality and flavor of their meat and fishing, as can be observed by annual championships of peacock in the rivers where it is. To understand this fast process of occupation and adaptation to new environments, 78 specimens of C. kelberi were caught monthly between the months of March 2009 to February 2010 with the aid of fishing pole and hook, from the Lagoa do Pernilongo (20º 29' 11,93"S, 51º 25' 33,27"O) and Ilha da Ferradura (20º 28' 27,11" S, 51º 25' 54,53"O), in the Jupiá Reservoir, Parana River, Ilha Solteira, São Paulo, Brazil, where it was introduced. It was defined four gonadal maturation class to the annual reproductive cycle of the yellow peacock bass C. kelberi. The definition of the Early Maturation, Mid Maturation, Final Maturation and Regression Classes, were based on the changes of the testicular germinal epithelium associated with the germ cell stages present. The Class of Early Maturation is characterized by the presence of a fully continuous germinal epithelium, cysts with germ cells at all stages of development, intense spermatogenic activity throughout the testis and rare "clusters" peripherals, consisting of primary spermatogonia. The Mid maturation Class starts with the appearance of a discontinuous germinal epithelium in the anastomosed region with spermatogenesis decrease and sperm storage in this region. The peripheral groups of spermatogonia or "clusters" are missing at the end of this class of maturation. In the Final Maturation Class the germinal epithelium discontinuity reaches the periphery of lobules... (Complete abstract click electronic access below) / Mestre
7

Fecundación "in vitro" en la especie porcina: influencia de diferentes condiciones de cocultivo

Coy Fuster, Pilar 13 December 1991 (has links)
Con el presente trabajo se ha pretendido investigar la influencia de diversos factores relacionados con el cocultivo de los gametos porcinos, sobre los resultados de la fecundación" in vitro" (AV), fundamentalmente con la intención de mejorar la eficacia actual del sistema de AV en cuanto a la consecución de embriones viables (fecundaciones monospérmicas). Para ello, se han utilizado 129 hembras porcinas prepúberes a las que se indujo la ovulación mediante un tratamiento con 1250 U.I. de PMSG y 750 U.I. de HCG. El tratameinto empleado resultó eficaz para los fines perseguidos en un 80'62% de las hembras y el número medio de ovocitos recogidos fue de 19'07 + 1'52 por animal, utilizándose un total de 1984 ovocitos.En relación a las condiciones del sistema de fecundación, el primer factor investigado ha sido el tiempo de cocultivo, entendido como tiempo de contacto entre los gametos. En las dos experiencias realizadas, utilizando tiempos de 4, 6 u 8 horas (experiencia la), o de 1, 2, 3 ó 4 horas (experiencia lb), los mejores resultados se obtuvieron tras 4 horas de cocultivo, ya que los porcentajes de penetración de mantuvieron altos con respecto al máximo alcanzado a las 8 horas (82,68 vs. 93,96%), mientras que los de monospermia no disminuyeron excesivamente con respecto a los obtenidos con tiempos de cocultivo menores, teniendo en cuenta que la concentración de espermatozoides empleada fue intencionadamente elevada (12 x 105 esp/ml). El segundo factor analizado fue la concentración espermática. Se utilizaron concentraciones de 3, 6 y 12 x 105 esp vivos/ml, deduciéndose de los resultados que la mayor efectividad en nuestro sistema correspondía a la concentración de 6 x lO 5 esp/ml, ya que los porcentajes de penetración fueron significativamente diferentes a los obtenidos con la concentración espermática más alta (71'62% vs. 76'83%), y los porcentajes de monospermia tampoco se diferenciaron de los obtenidos con la concentración espermática más baja (62'26 vs. 68'08%). El tercer factor estudiado ha sido la influencia de la presencia o ausencia en el medio de cocultivo del "cumulus" expandido que acompaña al ovocito en la ovulación. Por los resultados obtenidos, se puede pensar que la presencia estas células junto con la correspondiente matriz intrecelular de ácido hialúrico es altamente beneficiosa para la mejora del rendimiento de la FIV debido a que los porcentajes de penetración en los ovocitos denudados (53'69 fueron menores (p<0'0l) que los obtenidos en los ovocitos con "cumulus" (69'10%), mientras que los porcentajes de monospermia fueron superios (p < 0'01) en el segundo caso (39'45% vs. 60'97%). Por último, se ha investigado el efecto de la reducción del volumen medio de cocultivo más comúnmente utilizado (2 mI) a otro menor (0'4 n obteniéndose resultados equivalentes en ambos casos para los porcentajes penetración, pero mayores porcentajes de monospermia (p<0'05) con volumen de 0'4 mI (57'53% vs. 78'12%). Del conjunto de los resultados se deduce que los porcentajes de penetración y polispermia en la AV porcina son consecuencia de la influencia de diferentes factores, entre los que se encuentran el tiempo de cocultivo, concentración espermática, la presencia del "cumulus oophorus" y el volumen de medio de cocultivo utilizados. / In the present work, we have investigated the influence of differen factors, related to porcine gametes coculture, on the results of "in vitro" fertilization (IVF). We have try to improve the efficiency of the current system to get viable embryos (monospermic fertilizations). 129 prepuberal gilts have been used after the induction of ovulation by administration of 1250 I.U. of PMSG followed, 55 hours later, by 750 I.U. of HCG. The results showed that the best moment for the recovery of oocytes was 44 h after HCC administration. In the same way, the treatment followed was effective for the required objectives in 80.62% of the studied females and the medium number of recovered oocytes was 19.07 + 1.52 per animal, giving a total number 01 1984 oocytes used. In relation with the conditions of the fertilization system, the first investigated factor was the coculture time, understanding it as contact time between gametes. To study the effect of this factor, two experiences were realized; fot the first one, 4, 6 or 8 hours of coculture time were used (experience lb) The best results were obtained at 4 hours of coculture, because the percentage of penetration was maintained high (82.68%) and, at the same time, the percentage of monospermy increased (p<O.Ol), although the sperm concentration employed was deliberately high (12 x lOS spx/ml). The second investigated factor was the sperm concentration. The results showed that, among the used concentrations (3, 6 and 12 x lO 5 alive spz/ml), the maximum effectiveness in our system was obtained for the concntration of 6 x lOS spz/ml, since the percentage of penetration was not signficatively different of that obtained with the highest sperm concentration The third studied factor was the influence of the presence or absence of the expanded ."cumulus", which is shed with the oocytes at the ovulation, in the coculture medium. The presence of these cells joined with the intercellular matrix of hialuronic acid was highly beneficious for the improvement of the IVF, because of the percentage of penetration with the denuded oocytes (53.69%) was lower (p<0.01) than that obtained with the .cumulus" enclosed oocytes (69.16%), and the percentage of monospermy was higher (p<0.01) at the second case (39.45% vs. 60.97%). Finally, the percentage of penetration and monspermy was investigated using two different coculture medium volume, one the commonly used by other authors (2 ml) and another minor volume (0.4 mI). The results showed that the percentage of monospermy was higher (p<0.01) with the 0.4 mI volume (57.53 vs.78312%). We may deduce from the total results that the percentages of and monospermy in porcine IVF are due to the influence of different factors, some of them being the coculture time, the sperm concentrarían, the presence of "cumulus". and the coculture medium volume.
8

Elevação da temperatura testicular e sua influência sobre a compactação da cromatina e morfometria espermática em coelhos (Oryctolagus cuniculus) / Testicular temperature rise and its influence on compacting chromatin and sperm morphometry in rabbits (Oryctolagus cuniculus)

Kanayama, Cláudio Yudi 02 March 2010 (has links)
One performed a more modern approach on such heat stress to find changes out to compact morphometry in spermatozoon head by computational analysis. One aimed in this work to assess how to compact chromatin and sperm morphometry after have risen testicular temperature, by using experimental cryptorchidism in rabbits (Oryctolagus cuniculus), as well as used 30 rabbits: wild rabbit, white, adult, located in the rabbit keeping of University of Uberaba, Uberaba (city), MG (State of Minas Gerais), Brazil. One classified the rabbits into two groups of 15. Both groups were anesthetised, but only the experimental cryptorchidism one underwent a surgical operation. One gathered semen samples within a total of 69 days. One both dyed semen smear of all rabbits by using a toluidine blue dye and afterwards analysed it with a digital microcomputer to assess compacting chromatin and sperm morphometry. Chromatin varied regarding compact intensity (Diff%), homogeneity by coefficient of variation (CV) and aberrant chromatin (AbChr). By analysing morphometrically one assessed: area, perimeter (Perim.), width (w.), length (l.), ratio width:length (w./l.), ellipsity (E.), form factor (FF), lateral symmetry (LatSym), antero-posterior symmetry (A-PSym), and Fourier descriptors with amplitude from 0 to 2. Testicular temperature rise swayed the concentration, motility, and vigour adversely. Chromatin structure becomes aberrant when affected by testicular heat stress. And spermatozoon head tends to lessen. / Uma abordagem mais moderna sobre a elevação da temperatura foi realizada, visando detectar alterações na compactação e morfometria da cabeça do espermatozoide pela análise computacional. O objetivo do trabalho foi avaliar a compactação da cromatina e a morfometria espermática após a elevação da temperatura testicular, por meio de criptorquidismo experimental, em coelhos. Foram utilizados 30 coelhos da raça Nova Zelândia, brancos, adultos, situados no coelhário da Universidade de Uberaba, Uberaba, MG, Brasil. Os coelhos foram separados em dois grupos de 15. Ambos os grupos foram anestesiados, mas somente um deles sofreu intervenção cirúrgica, o criptorquidismo experimental. Foram coletadas amostras de sêmen durante 69 dias. Esfregaços de sêmen de todos os coelhos foram corados com azul de toluidina e, posteriormente, analisados digitalmente por meio de microcomputador para avaliar a compactação de cromatina e morfometria. A cromatina foi avaliada quanto à intensidade de compactação (Dif%), homogeneidade pelo coeficiente de variação (CV) e cromatina anômala (Cr. An.). Na análise morfométrica foram avaliados: área, perímetro (Per.), largura (Larg.), comprimento (Comp.), razão largura:comprimento (L/C), elipsidade (E), fator forma (FF), simetria lateral (Sim. Lat.), simetria ântero posterior (Sim. A-P) e descritores Fourier com amplitude de 0 a 2. A elevação da temperatura testicular influenciou negativamente a concentração, motilidade, vigor, torna-se anômala a estrutura da cromatina e a cabeça do espermatozoide tende a diminuir. / Mestre em Ciências Veterinárias
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Avaliação In vitro do sêmen caprino criopreservado em diluente acrescido de superóxido dismutase e catalase em diferentes concentrações

BARROS, Maria Shírlei Rodrigues de Moraes 24 February 2010 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-10-18T17:08:25Z No. of bitstreams: 1 Maria Shirlei Barros.pdf: 885582 bytes, checksum: 12e5ba4dbe4dbc6811c0b54fef726658 (MD5) / Made available in DSpace on 2016-10-18T17:08:25Z (GMT). No. of bitstreams: 1 Maria Shirlei Barros.pdf: 885582 bytes, checksum: 12e5ba4dbe4dbc6811c0b54fef726658 (MD5) Previous issue date: 2010-02-24 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / With the objective of to evaluate mitochondrial membrane potential (MMP), kinetic, the structural and ultrastructural of goat sperm submitted to freezing in skimmed-milk and glycerol, superoxide dismutase and catalase. It was used five bucks of Boer race, submitted to semen collect by artificial vagina. Semen samples were diluted in skimm-milk plus glycerol (7%), aiming have 320x106 sperm/mL, supplemented with antioxidants according to the experimental groups: G1) extender (control), G2) extender SOD + 25 IU/mL; G3) extender + SOD 50 IU/mL; G4) extender + SOD 100 IU/mL; G5) extender + CAT 25 IU/mL; G6) extender + CAT 50 IU/mL; G7) extender + CAT 100 IU/mL and G8) extender + SOD 100 IU/mL + CAT 25 IU/mL. Then the samples were packed in straws (0.25 mL), frozen and stored in cold storage cylinder (-196 oC). After thawing (37 ºC/30 seconds), aliquots of semen frozen/thawed of each group were evaluated to PMM, kinetic (CASA), structure and ultrastructure of spermatozoa, where did not observe significant difference (P>0.05) among experimental groups in parameters PMM, kinetic, iMP and iAc. In ultrastructural evaluation, fresh sperm was morphologically preserved mainly on mitochondrial membrane. Analyzes of thawed cells showed greater quantity of damages on acrosome; however, in lower percentage on G8 cells. G7 cells showed ultrastructural damages in acrosomes of 92.31%ofspermatozoas. In contrast, great percentage of spermatozoa have plasma and acrossomal membranes intacts, mainly on G2, G4 and G8 groups. Based on the ultrastructural results, it can be recommended addition of SOD (100 U/mL) and CAT (25 U/mL) on the freezing goat semen diluents with skimmed-milk and glycerol; as well as other studies should be realized using higher concentrations than 100U/mL of SOD in this diluent to freezing goat semen, associated to in vivo evaluation of these antioxidant action. / Objetivou-se com esse estudo avaliar o potencial de membrana mitocondrial (PMM), cinética, estrutura e ultraestrutura de espermatozoides caprinos, submetidos à criopreservação com diluente à base de leite desnatado e glicerol (7%), suplementado com superóxido dismutase (SOD) e catalase (CAT), em diferentes concentrações. Foram utilizados cinco reprodutores caprinos da raça Boer, submetidos à colheita de sêmen com vagina artificial. As amostras de sêmen foram diluídas em leite desnatado acrescido de glicerol (7%), de forma a apresentar 320x106 espermatozoides/mL, e suplementados com antioxidantes de acordo com os grupos experimentais: G1) diluente (Controle); G2) diluente + SOD 25 U/mL; G3) diluente + SOD 50 U/mL; G4) diluente + SOD 100 U/mL; G5) diluente + CAT 25 U/mL; G6) diluente + CAT 50 U/mL; G7) diluente + CAT 100 U/mL e G8) diluente + SOD 100 U/mL + CAT 25 U/mL. Em seguida, as amostras foram acondicionadas em palhetas (0,25 mL), congeladas e armazenadas em botijão criobiológico (-196o C). Após descongelação (37 oC/30 segundos), alíquotas de sêmen de cada grupo foram avaliadas quanto a PMM, cinética (CASA), iMP, iAc e ultraestrutura (microscopia eletrônica de transmissão). Não se constatou diferença significativa (P>0,05) entre os grupos experimentais dos parâmetros PMM, iMP, iAc e cinética espermática. Na avaliação ultraestrutural, espermatozoides in natura apresentaram-se morfologicamente preservados, principalmente na membrana mitocondrial. A análise das células pós-descongelação evidenciou maior quantidade de danos no acrossoma, todavia emmenor porcentual nas células do G8. O G7 apresentou dano ultraestrutural no acrossoma de 92,31% dos espermatozoides avaliados. Em contrapartida, grande porcentagem de espermatozóides apresentaram membrana plasmática e acrossomal intactas, principalmente nos grupos G2, G4, e G8. Com base nos resultados de ultraestrutura, é possível recomendar a adição de SOD (100U/mL) e CAT (25 U/mL) ao diluente de congelação do sêmen caprino à base de leite desnatado e glicerol; assim como outros estudos devem ser realizados utilizando concentrações maiores do que 100U/mL de SOD neste diluidor de congelação de sêmen caprino, associado à avaliação in vivo da ação deste antioxidante.
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Mechanisms and consequences of DNA damage, response and apoptosis in spermatozoa

Laubenthal, Julian January 2011 (has links)
DNA damage in spermatozoa is a crucial contributor to spontaneous abortion, severe genetic disease in the offspring and infertility. The chromatin of spermatozoa is highly compacted, transcriptionally and translationally silent, hence lacking DNA damage response (DDR). DDR foci follow within seconds after a DNA double strand break (DSB) and correlate to an abortive topoisomerase-IIb activity during spermiogenesis. When comparing the DSB frequencies at the two most fragile genomic loci (fragile sites FRA3B, FRA16D) in human and murine spermatozoa with lymphocytes, significantly increased DSB levels were detected in spermatozoa in both species. This corroborates that spermatozoa are more prone to DSBs than somatic cells. When comparing the DSB frequencies at FRA3B/FRA16D in spermatozoa of smokers with non-smokers, two-fold increases were found, probably caused by cigarette smoke components triggering abortive topoisomerase-IIβ activity. The phosphorylated DDR proteins H2AX and ATM were identified in human spermatozoa and murine spermatids using multicolour immunostaining with laser-scanning confocal microscopy (LSCM) and Western blots. Based on significantly increased DDR foci in spermatozoa of smoking men, but lacking DDR foci in response to in vitro challenge with H2O2, an abortive topoisomerase-IIb activity is the likely cause of DDR foci in spermatozoa. As DDR foci are susceptible to cigarette smoke, they can potentially be used as a novel biomarker. When comparing paternal spermatozoa, and lymphocytes as well as maternal and cord lymphocytes from 39 families for DSBs (via high-throughput LSCM pH2AX detection) and DNA fragmentation (Comet assay), significant increases were found in newborns of mothers exposed to environmental tobacco smoke and smoking fathers. When challenging lymphocytes and spermatozoa to different genotoxicants, significantly increased DNA damage in newborns compared to adults was found. This confirms an exceptional vulnerability in newborns, believed to cause increased susceptibly to disease in later life, including cancer.

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