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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.
91

Utilização de antioxidantes na criopreservação de sêmen da cauda do epidídimo de bovinos / Use of antioxidants on sperm cryopreservation, animal genetic resources, catalase, epididymis tail, reactive oxygen species, trolox

Rodrigues , Aline Luciana 08 April 2011 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-09T12:50:08Z No. of bitstreams: 2 Dissertação - Aline Luciana Rodrigues - 2011.pdf: 1902000 bytes, checksum: f7591f34d543c33bcea4f08d4cb14fa8 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-09T14:43:06Z (GMT) No. of bitstreams: 2 Dissertação - Aline Luciana Rodrigues - 2011.pdf: 1902000 bytes, checksum: f7591f34d543c33bcea4f08d4cb14fa8 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-09T14:43:06Z (GMT). No. of bitstreams: 2 Dissertação - Aline Luciana Rodrigues - 2011.pdf: 1902000 bytes, checksum: f7591f34d543c33bcea4f08d4cb14fa8 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2011-04-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The interest in the preservation of species threatened of extinction has increased the attention for cryopreservation of semen from the epididymis tail of animals that have died. Determination of the time in which the sperm is still viable for preservation represents a benefit for future research and use in animal-assisted breeding programs. In addition, the sperm cryopreservation process results in the production of radical free by the metabolism of the cell causing damage. The objectives of this study were: 1) to determine the viable time interval for cryopreservation of the epididymis tail sperm in cattle, 2) to test the addition of two antioxidants in the freezing media, 3) to determine the viability of semen samples from the tail of the epididymis in the production of embryos by in vitro fertilization. To guarantee the quality of freezing, the parameters: motility, vigor and sperm pathology in the pre-freezing were analyzed. After these assessments the material was divided into three treatments: tris-egg yolk diluent (TTG), Tris-egg yolk diluent catalase (TCAT) and tris-egg yolk diluent trolox (TTROL) and frozen in determined curve by pre-freezing automated process. After thawing, the motility and vigor were evaluated using CASA. Analysis of plasma membrane integrity and acrosome, test resistance thermometer (TTR), thiobarbituric acid reactive substances (TBARS), oxidation of 3,3 'diaminobenzidine (DAB) and in vitro fertilization (IVF) were also evaluated. According to the movement patterns analyzed using CASA, the analysis of data generated by the study allow us to conclude the characteristics of sperm in each treatment and it change on the different times of cooling (0h, 24h, 48h and 72h). In the assessment of integrity (INT) and injured sperm (LS), no statistical differences between the moments or between treatments were observed. Rates of cleavage D7 and D8 were statistically different, at 72 hours the trolox showed negative action. The results shown indicate that this procedure is important for conservation of animals of high genetic value or animals endangered that die suddenly. Further studies should be performed testing associations of antioxidants directly in the middle of fertilization and embryo culture, especially in production systems of embryos with high oxygen tension, as used in this experiment. xxii / O interesse pela preservação de espécies em risco de extinção tem aumentado a atenção pela criopreservação de sêmen da cauda do epidídimo de animais que morrem subitamente. A determinação do momento até quando os espermatozóides estão viáveis para preservação representa um benefício para pesquisas futuras e sua utilização em programas de reprodução animal assistida. Além disso, o processo de criopreservação dos espermatozóides resulta na produção de radicais livres pelo próprio metabolismo desta célula e causando danos. Os objetivos deste estudo foram: 1) determinar o intervalo de viabilidade de resfriamento de espermatozóides da cauda do epidídimo de bovinos, 2) testar o efeito da adição de dois antioxidantes nos meios de congelação, 3) determinar a viabilidade das amostras de sêmen da cauda do epidídimo na produção de embriões por fertilização in vitro. Para garantia da qualidade da congelação foram realizadas análises de motilidade, vigor, patologia espermática, no momento pré-congelação. Após estas avaliações o material foi dividido em três tratamentos: diluente tris-gema-glicerol (TTG), diluente tris-gema-glicerol com catalase (TCAT) e diluente tris-gema-glicerol com trolox (TTROL) e congelados em curva pré-determinada por processo de congelação automatizada. Após a descongelação foram avaliadas a motilidade e vigor com auxílio do CASA, análises de integridade de membrana plasmática e acrossoma, teste de termorresistência (TTR), substâncias reativas ao ácido tiobarbitúrico (TBARs), oxidação da 3,3’ diaminobenzidina (DAB) e fertilização in vitro (FIV). De acordo com os padrões de movimentos observados pelo CASA, a análise dos dados gerados pelo estudo nos possibilitam concluir as características dos espermatozóides em cada tratamento e como se comportaram nos momentos de resfriamento logo após o abate, 24 horas, 48 horas e 72 horas após resfriamento à 5ºC ( 0h, 24h, 48h e 72h). O uso dos antioxidantes não garantiu melhor proteção e nem auxílio na funcionalidade dos espermatozóides do epidídimo nos diferentes períodos de resfriamento. lulas imóveis) não houve diferenças estatísticas. Nas taxas de clivagem D7 e D8 foram observadas diferenças estatísticas, o α-tocoferol no momento 72 h demonstrou ação negativa. Os resultados demonstrados revelaram que tal procedimento é de suma importância para conservação de animais de alto xx valor genético ou animais em risco de extinção que morrem subitamente. Novos estudos devem ser realizados testando associações de antioxidantes ou o uso de antioxidantes diretamente no meio de fecundação e cultivo embrionário, especialmente em sistemas de produção de embriões com alta tensão de oxigênio, como o utilizado neste experimento.
92

Cultiu de les cèl·lules epididimàries de "Sus domesticus": anàlisi estructural, funcional i proteòmic

Bassols Casadevall, Judit 21 June 2006 (has links)
En aquest treball s'han desenvolupat dos mètodes simples i ràpids pel cultiu de les cèl·lules epitelials de les tres regions de l'epidídim de Sus domesticus. Un es basa en el cultiu de fragments del túbul epididimari intactes durant 8 dies. L'altre mètode es basa en el cultiu de fragments del túbul epididimari digerits amb col·lagenasa que, després de 7 dies, donen lloc a la formació d'una monocapa de cèl·lules epitelials epididimàries que adquireixen el 90-100% de confluència després de 12-16 dies en cultiu. Aquestes cèl·lules es mantenen viables durant més de 60 dies en cultiu i no s'observa proliferació de cèl·lules no epitelials. Per determinar el nivell de conservació de les característiques epididimàries en els cultius s'ha analitzat l'estructura cel·lular, l'activitat de síntesi i secreció proteica, i el manteniment i maduració dels espermatozoides en cocultiu. / In this work, we have developed two simple and quick methods for the culture of boar epididymal epithelial cells. The first one involves the culture of intact epididymal tubule fragments during 8 days. The second one involves the culture of epididymal tubule fragments digested with collagenase that, after 7 days in culture, allows the formation of an epididymal epithelial cell monolayer that reached 90-100% confluence after 12-16 days. These epididymal epithelial cells monolayers were maintained in vitro for more than 60 days and overgrowth of non-epithelial cells was not observed. To estimate the level of preservation of epididymal characteristics in these cultures we have focused on cell morphology, protein secretion activity, and sperm preservation and maturation.
93

Les gènes et protéines BSP chez la souris et l’humain : clonage, caractérisation, expression sous forme recombinante et étude des fonctions biologiques

Lefebvre, Jasmine 08 1900 (has links)
L’infertilité affecte environ 15% des couples en âge de se reproduire. Dans près de la moitié des cas, des facteurs masculins sont à la base de l’infertilité, quoique les causes exactes demeurent souvent inconnues. Les spermatozoïdes de mammifères subissent une série d’étapes de maturation avant d’acquérir la capacité de féconder un ovocyte. Les premiers changements ont lieu à l’intérieur de l’épididyme, où les spermatozoïdes gagnent la capacité de se mouvoir ainsi que de reconnaître et d’interagir avec l’ovocyte. Suite à l’éjaculation, ils doivent subir une seconde série de modifications à l’intérieur du tractus génital femelle, nommée capacitation. Nous avons préalablement démontré que chez le bovin, la famille de protéines BSP (Binder of SPerm) est essentielle à la capacitation. Des homologues des BSP ont aussi été isolés du fluide séminal de porc, de bouc, de bélier, de bison et d’étalon. Malgré la détection d’antigènes apparentés aux BSP dans le fluide séminal de souris et d’humain, les homologues des BSP n’ont jamais été caractérisés chez ces espèces. Nous avons émis l’hypothèse que des homologues des BSP seraient exprimés chez la souris et l’humain et joueraient un rôle dans la maturation des spermatozoïdes. Nous avons démontré que des séquences homologues aux BSP sont présentes dans les génomes murin et humain. Le génome murin contient trois séquences; Bsph1, Bsph2a et Bsph2b, tandis qu’une seule séquence (BSPH1) a été identifée chez l’humain. Les séquences d’ADNc de Bsph1, Bsph2a et BSPH1 ont été clonées, tandis que Bsph2b serait probablement un pseudogène. Les trois gènes sont exprimés uniquement dans l’épididyme et font partie d’une sous-famille distincte à l’intérieur de la famille des BSP. Chez les ongulés, les BSP sont exprimées par les vésicules séminales, sont ajoutées aux spermatozoïdes lors de l’éjaculation et représentent une proportion significative des protéines du plasma séminal. Au contraire, les BSP épididymaires ne sont retrouvées qu’en faibles quantités dans le fluide séminal. L’étude de leur rôle dans les fonctions spermatiques était donc plus difficile que chez les ongulés, où l’isolement des protéines natives du plasma séminal à l’aide de techniques de chromatographie était possible. Afin d’étudier sa fonction, nous avons exprimé BSPH1 recombinante dans E. coli. Les ponts disulfure des domaines de type-II caractéristiques de ces protéines ont fait en sorte que l’expression de BSPH1 fusionnée à une étiquette hexahistidine ou glutathion-S-transférase a donné lieu à des protéines insolubles dans les corps d’inclusion. La production de BSPH1 soluble a été possible grâce à l’ajout d’une étiquette thiorédoxine et l’expression dans une souche au cytoplasme oxidatif. BSPH1 a été purifiée par affinité et sa liaison aux partenaires connus des BSP, la phosphatidylcholine, les lipoprotéines de faible densité et la membrane des spermatozoïdes, suggérait que la protéine recombinante possédait sa conformation native et pouvait être utilisée pour des essais fonctionnels. La forme native de BSPH1 a été détectée dans le plasma séminal humain suite au fractionnement par gel filtration. La liaison de BSPH1 native à une colonne d’affinité à l’héparine a indiqué qu’elle partage aussi cette propriété de liaison avec la famille des BSP, et pourrait lier les GAGs semblables à l’héparine du tractus génital féminin. Une colonne d’immunoaffinité anti-BSPH1 a été préparée à l’aide d’anticorps générés contre des protéines recombinantes, et a permis d’isoler BSPH1 native à partir d’extraits de spermatozoïdes humains. Nos résultats montrent que BSPH1 native serait localisée dans les microdomaines « rafts » de la membrane. Sa masse moléculaire apparente était de 32 kDa, ce qui est supérieur à la masse prédite selon sa séquence en acides aminés, indiquant la présence probable de modifications post-traductionnelles, ou d’une migration anormale. L’effet de BSPH1 recombinante et des anticorps anti-BSPH1 sur la motilité, la viabilité et la capacitation a aussi été étudié. Les deux dernières variables ont été mesurées par un essai de cytométrie en flux, optimisé dans cette étude. Aucun effet des protéines recombinantes ou des anticorps sur la motilité et la viabilité des spermatozoïdes n’a été noté. Quoiqu’une stimulation modeste, quoique significative, de la capacitation ait été observée à la plus faible concentration de BSPH1, les concentrations plus élevées n’ont pas montré d’effet. De la même manière, les anticorps anti-BSPH1 n’ont pas eu d’effet significatif sur la capacitation. Ces résultats suggèrent que BSPH1 produite dans E. coli n’affecte pas la capacitation de façon marquée. Cependant, puisque BSPH1 native possède probablement des modifications post-traductionnelles, une protéine recombinante produite dans des cellules de mammifères pourrait affecter les fonctions spermatiques. De manière alternative, les BSP épididymaires remplissent peut-être un rôle différent dans les fonctions spermatiques que celles sécrétées par les vésicules séminales des ongulés. Les résultats décrits dans cette thèse pourraient contribuer à améliorer le diagnostic de l’infertilité masculine, ainsi que les techniques de reproduction assistée et éventuellement, pourraient mener au développement de contraceptifs masculins. / Infertility affects approximately 15% of couples of reproductive age. In nearly half the cases, male factors are responsible, although causes underlying male infertility often remain unknown. Mammalian sperm undergo a series of maturational steps before acquiring the capacity to fertilize an oocyte. The first changes take place inside the epididymis, where sperm gain motility and the ability to recognize and interact with the oocyte. After ejaculation, sperm go through a second maturation event named capacitation, taking place inside the female reproductive tract. We previously showed that in the bovine species, proteins of the BSP (Binder of SPerm) family are essential for capacitation. Homologs of these proteins have also been isolated from boar, ram, goat, bison and stallion seminal fluid. Although BSP-related antigens have been detected in mouse and human seminal fluid, BSP homologs have never been characterized in these species. We hypothesized that BSPs would indeed be expressed in mice and humans and could be involved in sperm maturation. Our studies demonstrated that BSP-homologous sequences are present in the mouse and human genomes. The mouse genome contains three BSP-like sequences, Bsph1, Bsph2a and Bsph2b, whereas only one sequence (BSPH1) was identified in the human genome. The complete cDNA sequences of Bsph1, Bsph2a and BSPH1 were cloned, whereas Bsph2b is probably a pseudogene. The two murine and sole human genes are expressed uniquely in the epididymis, and are part of a distinct sub-family within the BSP superfamily. The BSPs of ungulates are expressed in the seminal vesicles, are added to sperm upon ejaculation and represent a significant proportion of seminal plasma proteins. In contrast, BSP proteins expressed in the mouse and human epididymides are found in very small quantities in seminal fluid. The study of their role in sperm functions was therefore less straightforward than for ungulate species, where direct isolation of the native proteins from seminal plasma was feasible using various chromatography techniques. In order to investigate the role of the human BSP protein, BSPH1, we expressed the recombinant protein in E. coli. Probably due to the multiple disulfide bonds within the fibronectin type-II domains characteristic of these proteins, expression of BSPH1 with a hexahistidine or glutathione-S-tranferase tag gave rise to insoluble protein trapped inside bacterial inclusion bodies. Successful expression of soluble BSPH1 was achieved when the protein was fused to a thioredoxin tag and expressed in a bacterial strain that possesses an oxidizing cytoplasm. This protein was purified using affinity chromatography techniques and tested for binding to known ligands of BSP proteins: phosphatidylcholine, low-density lipoproteins and the human sperm membrane. Since recombinant BSPH1 displayed all three binding properties, we concluded that it had assumed its native conformation and could be used in subsequent functional assays to determine its role in sperm functions. The native form of BSPH1 was detected in human seminal plasma after fractionation on a gel filtration column. Native BSPH1 also bound to a heparin-affinity column, indicating that it shares this binding property with the BSP family and may also bind heparin-like GAGs of the female reproductive tract. An anti-BSPH1 immunoaffinity column was prepared using antibodies generated with bacterially expressed recombinant proteins and was used to isolate native BSPH1 from human sperm extracts. In addition, our results show that BSPH1 probably localizes to detergent-resistant microdomains of the human sperm membrane. Its apparent molecular weight was 32 kDa, which is superior to that predicted by its amino acid sequence. Therefore, BSPH1 probably undergoes post-translational modifications or migrates abnormally during electrophoresis. The effect of recombinant BSPH1 protein and anti-BSPH1 antibodies on human sperm motility, viability and capacitation were also investigated. The latter two sperm functions were assayed using a flow cytometry technique optimized in this study. No effect of recombinant BSPH1 or antibodies on sperm motility or viability was noted. Although a modest yet significant stimulation of capacitation was observed at lower BSPH1 protein concentrations, higher concentrations showed no effect. In the same fashion, anti-BSPH1 antibodies showed no significant effect on capacitation. These results suggest that recombinant BSPH1 produced in E. coli does not appreciably affect capacitation. However, since native BSPH1 may be subject to post-translational modifications, it is possible that BSPH1 expressed in a mammalian system would affect sperm capacitation. Alternatively, epididymally expressed BSPs may play a somewhat different role in sperm functions than those secreted by the seminal vesicles of ungulates. The results described in this thesis could aid in better diagnosing male infertility, improving assisted reproduction and eventually, developing male contraceptives.
94

Detecção de anticorpos e pesquisa de DNA de Leptospira spp. e Brucella spp. em bovinos abatidos no Estado do Rio Grande do Norte / Detection of antibody and search of Leptospira spp. and Brucella spp. in cattle slaughtered in state of Rio Grande do Norte

Araújo, Kênia Suênia Meira de 31 August 2012 (has links)
Made available in DSpace on 2016-08-15T20:31:15Z (GMT). No. of bitstreams: 1 KeniaSMA_DISSERT.pdf: 1150269 bytes, checksum: 54d277c76ed42d8d5e0470e502ceca2f (MD5) Previous issue date: 2012-08-31 / This study was aimed at researching anti-Leptospira spp. and anti-Brucella spp. agglutinins in cattle slaughtered in public slaughterhouses in the State of Rio Grande do Norte, as well as confirm the presence of these agents through PCR in the ovaries and epididymides of the slaughtered animals. For such purpose, serum, and ovary or epididymides were collected from cattle at the public slaughterhouses of that state. Sampling was performed during normal slaughter line, without any interference as the order, sex, age, or origin of the slaughtered animals. The screening of animal reagent to leptospirosis was made through the Microscopic Agglutination Test (MAT). To search for brucellosis, animals were screened by the Buffered Acidified Antigen test (BAA) and as a confirmatory test 2-mercaptoethanol (2-ME) was used. To detect bacterial DNA in samples of ovary and epididymides the Polymerase Chain Reaction (PCR) was used. Of all the 306 animals evaluated, 189 (61.76%) were positive for the MAT, where the predominant serovar was Hardjo (24.9%). The second most frequent serovar was Wolffi (14.8%), followed by Butembo, Icterhaemorrragiae, and Hebdomadis who contributed with frequencies ranging from 6.9% to 2.6%. Lower frequencies were found for the serovars Australis (1.6%), Pomona (1.1%), Grippotyphosa (1.1%) and Patoc (1.1%). Canicola, Autumnalis, and Sentot had frequencies lower than 1%. Three animals were positive for the BAA test, however only one of these reacted positively to 2-ME. Not one of the samples was positive for Brucella spp. and Leptopira spp. DNA through the PCR technique. Given the above mentioned data it was concluded that the Leptospira spp. infection in cattle in the semiarid region of Rio Grande do Norte occurs at higher frequency with the serovar Hardjo during the dry season of the year. The Brucella spp. infection is present but has very low frequency, and no DNA from Leptospira spp. and Brucella spp. was detected in the ovary and epididymis samples of the cattle examined / Objetivou-se pesquisar aglutininas anti-Leptospira spp. e anti-Brucella spp. em bovinos de abatedouros públicos no Estado do Rio Grande do Norte, bem como confirmar através da PCR, a presença desses agentes nos ovários e epidídimos desses animais. Para isso, foram colhidos durante a linha normal de abate, o sangue e ovário ou epidídimo, de 306 animais no período de dezembro de 2010 a agosto de 2011. Através da Reação de Soroaglutinação Microscópica (SAM) foram detectados 189 (61,76%) animais sororeagente para Leptospira spp., sendo o sorovar Hardjo (24,9%) o mais predominante, seguido do Wolffi, Butembo, Icterhaemorrragiae e Hebdomadis que contribuiram com frequências que variaram de 14,8% a 2,6%. Os sorovares Australis, Pomona, Grippotyphosa, Patoc, Canícola, Autumnalis e Sentot foram menos frequentes. Em análise em separado, o sorovar Hadjo apresentou maior ocorrência no período seco do que no chuvoso (p=0,031). Para a brucelose os animais foram triados através da prova do Antígeno Acidificado Tamponado (AAT) e confirmados pela prova do 2-mercaptoetanol (2-ME). Três animais foram positivos ao AAT, desses apenas um reagiu positivamente ao 2-ME. A PCR foi utilizada para detecção do DNA bacteriano nas amostras de ovário e epidídimo. Nenhuma amostra foi positiva na PCR para detecção de DNA da Brucella spp. e Leptospira spp. Diante do exposto conclui-se que a infecção por Leptospira spp. em bovinos ocorre no semiárido do Rio Grande do Norte com maior frequência para o sorovar Hardjo durante o período seco do ano. A brucelose foi detectada, mas com baixa frequência. Através da PCR não foi detectado DNA de Leptospira spp. e Brucella spp. nos ovários e epidídimos dos animais
95

Contrôle des dommages oxydants au noyau spermatique : apports des modèles murins knock-out pour des glutathion peroxydases / Control of oxidative damage to the spermatic nucleus : contribution of knock-out mouse models for glutathione peroxidases

Noblanc, Anaïs 05 July 2013 (has links)
Les spermatozoïdes acquièrent leur pouvoir fécondant et leur mobilité lors de leur transit le long de l’épididyme. Paradoxalement, cette maturation épididymaire nécessite la présence d’espèces oxygénées réactives (EOR) pour condenser la chromatine spermatique afin de mieux protéger l’ADN de ces mêmes molécules. Nous avons étudié la façon dont l’épididyme parvient à assurer l’équilibre entre un déficit et un excès d’EOR en caractérisant le phénotype épididymaire de souris dont la production de deux enzymes antioxydantes glutathion peroxydases a été invalidée, GPx5 et snGPx4. L’épididyme de ces souris génère une réponse antioxydante élevée et augmente l’activité de pontage disulfure sur les gamètes en modulant l’expression génique d’enzymes antioxydantes (Trx, Prx, GST, SOD3, catalase) et de protéines disulfide isomérases (Pdia). Bien que ce sursaut d’activité soit efficace pour protéger les membranes du tissu et des spermatozoïdes, la chromatine des spermatozoïdes présente un défaut de condensation, laissant l’ADN spermatique vulnérable face aux EOR. Les gamètes présentent alors des dommages oxydants dans le noyau qui s’aggravent avec la diminution de l’activité antioxydante lors du vieillissement. Des approches immunologiques et biochimiques ont montré que les dommages oxydants se produisent préférentiellement sur l’ADN spermatique situé à la périphérie du noyau, qui est enrichi en nucléosomes persistants et qui est associé à la matrice nucléaire. Afin de déterminer s’il est possible de diminuer ces atteintes oxydantes sur les gamètes, nous avons étudié les effets d’une supplémentation orale antioxydante sur des souris sauvages et sur l’un de nos modèles murins mutant. / The spermatozoa acquire their fertilizing ability and their motility through the epididymis. Paradoxically, this epididymal maturation needs reactive oxygen species (ROS) to condense the sperm chromatin permitting to protect the DNA against these molecules. We studied how the epididymis ensure the equilibrium between deficit and excess of ROS by characterizing the epididymal phenotype of mice lacking two antioxidant activities of the glutathione peroxidase family, GPx5 & snGPx4. The epididymis of these mice produce a strong antioxidant response and also increase the disulfide bridging activity by adjusting the gene expression of antioxidant enzymes (Trx, Prx, GST, SOD3, catalase) and disulfide isomerase proteins (Pdia). This protection is efficient for tissue and sperm membranes but not for sperm chromatin which is susceptible to decondensation. The sperm cells show oxidative damage in the nucleus, which worsen with the decrease of the antioxidant activity upon aging. Immunological and biochemical approaches indicated that oxidative damage occurred only on the sperm DNA at the periphery of the nucleus, which is enriched with persisting nucleosomes and associated to the nuclear matrix. Finally, to determine if these oxidative damages on the spermatozoa can be lowered, we studied the effects of an oral antioxidant supplement on wild type and gpx5-/- mice (Chabory et al., 2009).
96

Morfofisiologia do sistema genital masculino de ratos púberes e adultos após privação androgênica durante a pré-puberdade / Morphophysiology of male reproductive system of adult and pubertal rats after androgen deprivation during prepuberty

Perobelli, Juliana Elaine, 1985- 02 June 2012 (has links)
Orientador: Wilma De Grava Kempinas / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T10:45:10Z (GMT). No. of bitstreams: 1 Perobelli_JulianaElaine_D.pdf: 9640563 bytes, checksum: dea242a152c4f569490c3cdf5d5010c1 (MD5) Previous issue date: 2012 / Resumo: Os desreguladores endócrinos são agentes químicos capazes de agir como agonistas ou antagonistas dos hormônios endógenos, interferindo na homeostasia do organismo. Como o sistema endócrino tem papel crítico sobre o desenvolvimento e função do sistema genital, este pode ser considerado um alvo particularmente vulnerável a perturbações endócrinas. A literatura apresenta dados sobre a exposição aos antiandrogênicos durante a vida pré-natal e adulta e suas consequências sobre a função reprodutiva de machos. Entretanto, poucos estudos se atentaram para as consequências da privação androgênica durante a pré-puberdade sobre o sistema genital masculino. A pré-puberdade corresponde à fase em que o epidídimo, órgão reprodutor masculino responsável pela maturação e estocagem dos espermatozoides, passa por importantes mudanças morfofuncionais, além de consistir em período de maior susceptibilidade aos desreguladores endócrinos. O objetivo do presente estudo foi avaliar as possíveis consequências da privação de andrógenos durante a pré-puberdade sobre a morfofisiologia do sistema genital masculino de ratos púberes e adultos, com ênfase sobre o epidídimo e qualidade espermática. A escolha por um agente antiandrogênico foi devida à vasta exposição ambiental e ocupacional da população mundial a este grupo de contaminantes. Ratos machos da variedade Wistar foram alocados em: grupo flutamida (25mg/Kg/dia de flutamida, via oral, do dia pós natal 21 ao 44) e controle (óleo de milho, via oral, durante o mesmo período). Os animais foram avaliados aos 50 dias e 75 dias de idade. Foram analisados os níveis séricos dos hormônios sexuais (LH, FSH e testosterona), níveis de testosterona intratesticular, peso de órgãos, histologia testicular e epididimária, imunohistoquímica para marcação de receptor androgênico (AR), proteína espermática 22 (SP22), calmodulina (CALM) e Rab11A em tecido epididimário, além de marcação de CALM e Rab11A no testículo e western blot para AR no epidídimo. Avaliações adicionais foram realizadas nos animais de 75 dias, como comportamento sexual, fertilidade após acasalamento natural e inseminação artificial, motilidade e morfologia espermática, contagens espermáticas nos testículos e epidídimos, análise do perfil proteico de membrana espermática e contagem de células de Sertoli. No grupo tratado com flutamida, os animais púberes apresentaram redução do peso dos órgãos sexuais, relacionado à diminuição na testosterona sérica, além de alteração no padrão de imunomarcação para AR e CALM no epidídimo. Os demais parâmetros foram comparáveis entre os grupos experimentais. Nos animais de 75 dias de idade que receberam flutamida observou-se alteração no padrão de imunomarcação para AR, CALM e Rab11A no epidídimo, diminuição do potencial de fertilidade após inseminação artificial, comprometimento da motilidade espermática, diminuição do número de espermatozoides na cabeça/corpo e cauda do epidídimo, aceleração do trânsito espermático nestas regiões epididimárias e alteração na concentração de CALM e Rab11A na membrana espermática. Os demais parâmetros foram similares entre os grupos experimentais. Os resultados obtidos mostram que a privação de andrógenos durante a pré-puberdade causou alterações na qualidade dos espermatozóides prejudicando o potencial de fertilidade dos indivíduos na idade adulta. Tais resultados parecem estar associados a mudanças no perfil proteico da membrana dos espermatozoides e na expressão de determinadas proteínas no epitélio epididimário, sugerindo que o desenvolvimento pós-natal do epidídimo pode ter sido comprometido, acarretando danos funcionais permanentes ao órgão / Abstract: Endocrine disrupters are chemicals that can act as agonists or antagonists of endogenous hormones, interfering with the homeostasis of the organism. Since the endocrine system plays a critical role in the development and function of the male reproductive system, this is an especially vulnerable target of potential endocrine perturbations. The literature presents data on exposure to antiandrogens during the prenatal life and adulthood and its consequences on the male reproductive function. However, few studies have investigated the possible effects on the male reproductive system of rats after androgen deprivation during prepuberty. The prepubertal period comprehends the phase in which the epididymis, male reproductive organ responsible for the sperm maturation and storage, undergoes significant morphofunctional changes, besides being a period of more vulnerability to endocrine disrupters, possibly due to hormonal imprinting. The aim of this study was to evaluate the possible consequences of androgen deprivation during the prepuberty on morphophysiology of male reproductive system of pubertal and adult rats, focusing on the epididymis and sperm quality. The choice of an antiandrogen agent was due to extensive environmental and occupational exposure of the general population to this group of contaminants. For this purpose, Wistar male rats were divided into flutamide group (flutamide 25mg/Kg/day, orally, from postnatal day 21 to 44) and control group (corn oil, orally, during the same period). The animals were evaluated at 50 days and 75 days of age. At both ages it was evaluated the serum sexual hormone levels, intra-testicular testosterone levels, organ weights, testicular and epididymal histopathology, immunohistochemistry for androgen receptor (AR), sperm protein 22 (SP22), calmodulin (CALM) and Rab11A in epididymal tissue, besides immunostaining for CALM and Rab11A in the testis and Western blot for AR in the epididymis. Furthermore, additional parameters were assessed in 75-day-old animals, such as sexual behavior, fertility after natural mating and after artificial insemination, sperm motility and morphology, sperm counts in the testis and epididymis, proteomic of sperm membrane by bi-dimensional electrophoresis and Sertoli cells counts. Pubertal animals showed reduced reproductive organs weight, probably due to a decrease in serum testosterone and changes in the pattern of immunostaining for AR and CALM in the epididymis. The other parameters were comparable between the groups. In animals at 75 days old changes in the pattern of immunostaining for AR, CALM and Rab11A in the epididymis, decreased fertility potential after artificial insemination, impaired sperm motility, decrease in the sperm numbers in the caput/corpus and cauda epididymis, acceleration of sperm transit time through these epididymal regions, and modifications in three proteins of sperm membrane were observed. Other parameters were similar between the groups. The results show that androgen deprivation during prepuberty impairs sperm quality affecting the fertility potential of the animals at adulthood. These results seem to be related to the changes in protein profile of sperm membrane and protein expression in the epididymis, suggesting that the postnatal development of the epididymis may have been compromised, causing permanent damage to the organ function / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
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Insights Into The Hormonal Regualtion Of Epididymal Function : A Role For Estrogen

Deshpande, Shayu 11 1900 (has links) (PDF)
No description available.
98

Etude d'un récepteur orphelin apparenté aux récepteurs aux hormones glycoprotéiques, LGR4 / Study of an orphan receptor belonging to the glycoprotein hormone receptors family, LGR4

Van Schoore, Grégory 07 January 2008 (has links)
Les récepteurs couplés aux protéines G (RCPG) sont impliqués dans la majeure partie des communications intercellulaires. Un grand nombre de RCPG ont été découverts en comparant la séquence des récepteurs connus avec les données fournies par le séquençage du génome humain. Pour plus d'une centaine de ces récepteurs, le ligand activateur ou agoniste est inconnu. Ces récepteurs sont dès lors qualifiés d'orphelins.<p>Les LGR forment une sous-famille de RCPG structurellement proches de la rhodopsine qui comprend les récepteurs aux hormones glycoprotéiques (TSH, LH, hCG, FSH) et à la relaxine. LGR4 est un membre de cette famille dont ni la fonction précise, ni l'agoniste ne sont connus.<p>Dans un premier temps, une cartographie détaillée de l'expression de Lgr4 chez la souris a été obtenue. Nous avons tiré parti de l'existence d'une lignée de souris transgéniques dont le gène Lgr4 a été interrompu par l'introduction d'une cassette comportant deux marqueurs histologiques. L'activité beta-galactosidase d'un de ces marqueurs a été analysée chez les souris hétérozygotes. Ces dernières ne présentent pas de phénotype particulier, ce qui permet d'estimer que l'expression des marqueurs rend effectivement compte de l'expression normale du gène Lgr4. Lgr4 est exprimé dans un grand nombre de structures, notamment dans le cartilage, le rein, les appareils reproducteurs mâle et femelle et certaines cellules du système nerveux.<p>Ensuite, le phénotype des souris homozygotes pour l'inactivation de Lgr4 (LGR4KO) a été exploré. Ces souris présentent à la naissance un poids inférieur à leurs congénères des autres phénotypes. Les mâles sont stériles à cause d'une malformation des tubules efférents et de l'épididyme. Un blocage au niveau des tubules efférents reliant le testicule à l'épididyme contraint les spermatozoïdes à s'accumuler à la sortie du testicule, dans la région du rete testis. De plus, les tubes de l'épididyme, pourtant normaux à la naissance, ne s'allongent pas pour former la structure convolutée habituelle. L'épithélium de ces tubes est aplati et est entouré d'une quantité anormalement élevée de mésenchyme.<p>Dans un troisième temps, des outils nécessaires aux futures tentatives d'identification de l'agoniste naturel de LGR4 ont été réalisés. Il s'agit :(1) d'anticorps monoclonaux dirigés contre la partie extracellulaire du récepteur humain. (2) d'un appât moléculaire pour la ‘pêche au ligand’. Cet appât est constitué du domaine extracellulaire du récepteur humain couplé à un marqueur histologique. (3) d'une construction peptidique constituée du domaine extracellulaire du récepteur humain couplé à une queue poly-histidine. Cette construction est destinée à servir de greffon lors de chromatographies d'affinités devant permettre de purifier le ligand. (4) de lignées cellulaires exprimant le récepteur LGR4 humain ainsi que le système æquorine devant permettre de détecter l'activation de ce récepteur.<p>Les données apportées par ce travail montrent un rôle important du récepteur LGR4 au cours du développement et permettent de circonscrire le champ des recherches futures. Ceci, ainsi que les outils moléculaires développés, constitue une base pour l'identification future de l'agoniste et la détermination précise de la fonction de LGR4. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
99

Estudi citològic i bioquímic del fluid epididimari de "Sus domesticus"

Pruneda Sais, Anna 21 June 2006 (has links)
En aquest estudi s'ha determinat que al augmentar el ritme d'extraccions de semen es produeixen canvis en el patró d'absorció i secreció del fluid epididimari, que provoquen alteracions en la maduració epididimaria dels espermatozoides i un desenvolupament anòmal de la motilitat espermàtica.La concentració de glutamat i carnitina al fluid epididimari augmenten al llarg del conducte epididimari, alhora que la concentració de myo-inositol disminueix. El contingut de myo-inositol a l'interior dels espermatozoides disminueix, mentre que el contingut de glutamat augmenta a partir del caput distal i el contingut de carnitina no varia al llarg del conducte. S'ha determinat la presència de la ruta del poliol a l'epidídim de porcí. Els resultats obtinguts indiquen que la glucosa difon de la sang cap al fluid epididimari, és convertida a sorbitol per l'aldosa reductasa, i aquest sorbitol s'acumula al fluid luminal i és convertit a fructosa per l'acció de la sorbitol deshidrogenasa. / A high semen collection frequency brought about an altered resorption and secretion pattern of the epididymal fluid, which results in defective sperm maturation and abnormal development of sperm motility. In this study, it has been determined that in epididymal fluid the concentration of myo-inositol decreased in a proximo-distal direction, whereas intraluminal concentrations of L-carnitine and L-glutamate increased distally. The content of inositol in spermatozoa fell as they moved from the distal caput whereas sperm glutamate increased from the distal caput to more distal regions and carnitine content remained unchanged during epididymal transit. In this study, evidence for an operative polyol pathway was demonstrated in the porcine epididymis. The results found are consistent with diffusion of circulating glucose into the lumen, its conversion via aldose reductase to sorbitol which accumulates in the lumen and the action of sorbitol dehidrogenase on sorbitol to produce fructose.
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ESTUDO DE MORFOLOGIA MACROSCÓPICA, MICROSCÓPICA TESTICULAR E EPIDIDIMÁRIA EM EMAS (Rhea americana, Linnaeus 1758)(RHEIDAE) / Macroscopic and microscopic study in testes and epididymis of great rhea (Rhea americana, Linnaeus - 1758)(Rheidae)

CARVALHO, Saulo Fernandes Mano de 15 December 2010 (has links)
Made available in DSpace on 2014-07-29T15:13:56Z (GMT). No. of bitstreams: 1 TESE SAULO FERNANDES MANO DE CARVALHO.pdf: 5897981 bytes, checksum: 9ded1ddc23ddf1eb697350aee8c49480 (MD5) Previous issue date: 2010-12-15 / The purpose of this research was studied the macroscopic morphology of rhea s testis and epididymis. Were studied testis from 54 rheas, breed in captivity. In commercial slaughter, were collected testis to analyzed macroscopic measurements of testis and epididymis, consisting in length, width, thickness, circumference, volume, parenchyma and testicular capsule weight, also shape, size and blood supply. Of these parameters were calculated media and standard deviation. The testes looks like a cylinder, the testicular capsule is thin, dense and transparent, a short testicular artery arises from the A. cranialis renalis. The organs were influenced of season with reproductive and non reproductive times. In December/2006 and May/2007 the morphmetric media (x) measurements in right testes was: volume 58.70 and 14.7 mL , length 9.87 and 3.5 cm, width 2.44 and 0.6 cm, thickness 2.49 and 0.5 cm, circumference 8.02 and 2.3 cm, parenchyma weight 27.66 and 6.1 g and testicular capsule weight 1.04 and 0.3 g, respectively. In right epididymis was: volume 7.7 and 3.0 mL, length 5.8 and 1.3 cm, width 0.7 and 0.3 cm, thickness 0.6 and 0.3 cm, circumference 2.5 and 1.2 cm, parenchyma weight 6.4 and 2.8 g and capsule weight 0.4 and 0.1 g, respectively. A few of measurements, in testes and epididymis were bigger in right side than in left side (p<0.05) showing asymmetry. The medias of November/2005 were in intermediate position (p<0.05), but near the December/2006 data, probably it could be a transition phase between the rest and sexual activity (breeding season). The observations confirms sexual activity season in this specie, by spring summer. Morphologically the Rhea`s testicles and epididymis hava many points in common with other birds, but differences were observed, and has influence of seasons. The testicle and epididymis biometric characteristics were bigger in the breeding seasons. Key words: Aves, Epididymis, Morphology, Ratites, Reproduction, Seasonality, Testes / O objetivo desta pesquisa foi estudar a morfologia macroscópica de testículos e epidídimos de emas. Foram utilizados testículos de 54 emas, criadas em cativeiro. As coletas foram realizadas em novembro de 2005 (n=14), dezembro de 2006 (n=20) e maio de 2007 (n=20). Durante abate comercial foram colhidos os testículos e epidídimos e imediatamente foram aferidas as seguintes medidas do testículo e epidídimo: largura, comprimento, espessura, circunferência, volume, peso do parênquima e da túnica albugínea, também aspectos como sua forma, implantação na cavidade, relação com outros órgãos e vascularização. A partir das características estudadas calcularam-se média e desvio-padrão, sendo que as médias foram comparadas pela analise de variância. Os testículos apresentaram formato cilíndrico, túnica albugínea fina, densa e transparente, sua vascularização foi feita pela artéria testicular que é um ramo da artéria renal cranial. Nas coletas de dezembro/2006 e maio/2007 as médias das medidas macroscópicas dos testículos direitos foram: volume 58,7 e 14,7 mL, comprimento 9,87 e 3,5 cm, largura 2,4 e 0,6 cm, espessura 2,4 e 0,5 cm, circunferência 8,0 e 2,3 cm, peso do parênquima 27,6 e 6,1 g e peso da túnica albugínea 1,0 e 0,3 g, p<0,05, respectivamente. Em relação aos epidídimos as médias das medidas macroscópicas do órgão direito coletados de dezembro/2006 e maio/2007 foram: volume 7,7 e 3,0 mL, comprimento 5,8 e 1,3 cm, largura 0,7 e 0,3 cm, espessura 0,6 e 0,3 cm, circunferência 2,5 e 1,2 cm, peso do tecido 6,4 e 2,8 g e peso da cápsula 0,4 e 0,1 g, p<0,05, respectivamente. As médias observadas no mês de novembro/2005 ficaram em uma situação intermediária (p<0,05), porém quantitativamente bem mais próximas as do mês de dezembro/2006 o que pode caracterizar um período de transição. Algumas medidas do testículo e epidídimo direito foram superiores ao do esquerdo (p<0,05), caracterizando assimetria. Morfologicamente os testículos e epidídimos de emas possuem pontos em comum ao de outras aves descritas, porém diferenças foram observadas. Os testículos e epidídimos de Rhea americana apresentam influência do ambiente, com meses de atividade reprodutiva (novembro-dezembro) primavera-verão e outra de repouso sexual (maio) outono-inverno. Foram apresentadas as médias da biometria testicular e epididimária. As características da biometria testicular e epididimária apresentaram maior magnitude na estação de atividade sexual Palavras-chave: Aves, Epidídimo, Morfologia, Ratitas, Reprodução, Sazonalidade, Testículo

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