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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.
31

Some aspects of electrolyte and water transport in the rat epididymis

Au, Chak-leung. January 1979 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1980. / Also available in print.
32

Adrenergic control and its mechanism of stimulation of electrogenic anion secretion in primary cultures of rat epididymal eipthelial cells /

Chan, Po-tong, Timothy. January 1990 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1992.
33

Capacidade de ligação dos espermatozóides de epidídimo de equinos às células da tuba uterina cultivadas in vitro

Carneiro, João Alexandre Matos [UNESP] 18 June 2014 (has links) (PDF)
Made available in DSpace on 2015-01-26T13:21:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-06-18Bitstream added on 2015-01-26T13:30:36Z : No. of bitstreams: 1 000792285.pdf: 363368 bytes, checksum: bfcb9b7c5a5d2b307fa8df344ff91ccf (MD5) / Muitas biotecnologias estão sendo desenvolvidas visando a conservação do material genético de garanhões de alto valor zootécnico. Dentre estas pode-se destacar a colheita de espermatozoides do epidídimo de animais que sofreram algum trauma ou enfermidade que impossibilitem a colheita do sêmen, óbito ou eutanásia. Porém essas células espermáticas não entram em contato com o plasma seminal, importante por conter proteínas que participam de processos relacionados à proteção e ligação dos espermatozoides aos reservatórios espermáticos na tuba uterina. Neste sentido, sugere-se que haja importantes alterações bioquímicas nas células espermáticas do epidídimo, objetivando-se assim com esta revisão, estudar as principais diferenças morfofuncionais entre os espermatozoides provenientes do epidídimo e do ejaculado / Several biotechnologies are being developed aiming genetic material conservation of stallions with high zootechnical value, as we can highlight the harvest epididymis’s sperm of animals who suffered trauma or illness that makes impossible the semen collection, death or euthanasia. However these sperm cells do not get in touch with seminal plasma, important whereas it has proteins that participate in processes related to the protection and binding of sperm to the sperm reservoir in the oviduct. In this sense, it suggests that there is significant biochemical changes in epididymal sperm, aiming with this review to study the main morphological and functional differences between the sperm from the epididymis and ejaculated
34

Criopreservação e fertilidade de espermatozóides recuperados da cauda do epidídimo de garanhões

Monteiro, Gabriel Augusto [UNESP] 22 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-22Bitstream added on 2014-06-13T18:48:33Z : No. of bitstreams: 1 monteiro_ga_me_botfmvz.pdf: 8347367 bytes, checksum: 82c2cef3b1dcf4f8284dbffecca4034d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A recuperação de espermatozóides da cauda do epidídimo e sua criopreservação pode ser a última chance para recuperação do material genético quando ocorre morte súbita ou lesão grave em garanhões de alto valor genético. Sendo assim, o objetivo do experimento I foi comparar os parâmetros espermáticos dos espermatozóides da cauda do epidídimo recuperados imediatamente após orquiectomia e em diferentes momentos após armazenamento a 5°C e a temperatura ambiente. Já o experimento II, teve o objetivo de comparar os parâmetros espermáticos e fertilidade dos espermatozóides do ejaculado e do epidídimo recuperados logo depois da orquiectomia e após armazenamento por 24 horas a 5°C. No experimento I, 48 garanhões foram submetidos à orquiectomia bilateral, sendo que em oito a colheita dos espermatozóides do epidídimo foi realizada imediatamente após orquiectomia (grupo controle). Nos outros 40 garanhões, um epidídimo foi armazenado a temperatura ambiente e o contralateral armazenado a 5°C por 6, 12, 18, 24 e 30 horas, de acordo com o grupo. No experimento II, dois ejaculados de oito garanhões foram colhidos com vagina artificial e congelados (grupo EJ-0h). Uma semana após, os garanhões foram submetidos à orquiectomia bilateral, sendo que os espermatozóides de um epidídimo foram congelados imediatamente após orquiectomia (grupo EP-0h) e o epidídimo contralateral foi previamente armazenado por 24 horas a 5°C (EP-24h). O teste de fertilidade demonstrou que o grupo EP-0h (92,3%; n=13) tendem a ser maior que os grupos EJ-0h (61,5%; n=13) e EP-24h (61,5%; n=13). Conclui-se que o armazenamento dos testículos-epidídimos a 5°C proporcionou melhor preservação espermática e que, independente da temperatura, a motilidade progressiva é o parâmetro espermático mais sensível ao tempo de armazenamento. / Cauda epididymis sperm recovery and cryopreservation may be the last chance to obtain genetical material when sudden death or serious injury occur in valuable stallions. Thus, the aim of experiment I was to compare sperm parameters of epididymal sperm recovered immediately after orchiectomy and at different moments after storage at 5°C and at room temperature. Experiment II aimed to compare sperm parameters and fertility of ejaculated sperm and epididymal sperm recovered immediately after orchiectomy and after storage for 24h at 5°C. In experiment I, 48 stallions were submitted to bilateral orchiectomy, in eight of those the sperm collection were done immediately after orchiectomy (control group). In the other 40 stallions, one epididymis was stored at room temperature and the other was stored at 5°C for 6, 12, 18, 24 and 30 hours accorded to groups. In experiment II, two ejaculated from eight stallions were obtained with artificial vagina and cryopreserved (group EJ-0h). One week later, the stallions were submitted to bilateral orchiectomy, and the sperm of one epididymal were frozen immediately after orchiectomy (group EP-0h) and the contralateral epididymal was previously storage for 24h at 5°C (EP-24h). Fertility test showed that group EP-0h (92,3%; n=13) tended to be higher than groups EJ-0h (61,5%; n=13) and EP-24h (61,5%; n=13). These results allowed concluding that storage of the testis-epididymis complex at 5°C is more efficient in preserving sperm parameters than room temperature storage and that progressive motility is the parameter that is more affected by storage period, regardless of the temperature.
35

Caracteristicas estruturais e bioquimicas de segmentos epididimarios do hamster dourado Mesocricetus auratus

Beu, Celia Cristina Leme 31 May 2005 (has links)
Orientador: Antonio Marcos Orsi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-04T13:41:51Z (GMT). No. of bitstreams: 1 Beu_CeliaCristinaLeme_D.pdf: 7559585 bytes, checksum: 9cce3f7470d95982681f246437d4f90a (MD5) Previous issue date: 2005 / Resumo: O epitélio de revestimento do epidídimo do hamster dourado Mesocricetus auratus foi estudado nas regiões de segmento inicial, cabeça, corpo e cauda distal. As análises histológicas permitiram identificar células principais, basais, claras, halo e delgadas formando o epitélio de revestimento epididimário. As células principais predominaram na constituição do epitélio epididimário, apresentando contribuição relativa de 67,8% a 74,9% em sua formação. Células claras estavam presentes apenas na cauda distal, enquanto que as células delgadas não ocorreram apenas na cauda epididimária. As análises morfométricas mostraram que a altura epitelial variou ao longo do dueto epididimário, sendo que a maior altura ocorreu no segmento inicial (46,4mm) e a menor, na cauda distal (12,6 mm). As análises bioquímicas mostraram que as enzimas lactato desidrogenase e fosfatase alcalina apresentaram maior atividade na cauda epididimária. A maior concentração de proteínas totais ocorreu no segmento inicial com redução progressiva ao longo dos segmentos tubulares mais distais. Entre as células principais, claras e basais da cauda distal foram observados grandes espaços intercelulares, preenchidos com restos de membrana, estruturas semelhantes a figuras de mielina, vesículas, corpos multivesiculares ou material floculento. A observação destes espaços entre as células epiteliais da cauda distal sugere que há ocorrência de transcitose na cauda epididimária do hamster dourado, com possível passagem de água, entre outras substâncias, a partir do lúmen. A transcitose, possivelmente, influencia a formação do microambiente luminal epididimário. Os achados permitiram inferir que as regiões de cabeça e corpo do epidídimo estão envolvidas com as atividades iniciais de maturação dos espermatozóides e a cauda, além de armazenar os espermatozóides, deve ser o principal sítio para aquisição do potencial de fertilização / Abstract: The epididymis epithelium of the Golden hamster Mesocricetus auratus was studied at the initial segment, caput, corpus and distal cauda regions. The histological analyses identified principal, basal, clear, halo and narrow cells forming the epithelial lining of the epididymis. The principal cells predominated in the epididymis epithelium, contributing from 67.8% to 74.9% in its constitution. Clear cells were present only in the distal cauda, while the narrow cells did not appear only in the epididymal cauda. The morphometric analyses showed that the height of epithelial cells varied along the epididymal duct; the highest were observed at the initial segment (46.4 mm) and the lowest in the distal cauda (12.6 mm). The biochemical analyses showed that the lactate dehydrogenase and alkaline phosphatase were more activite in the epididymis cauda. The highest concentration of total proteins was verified in the initial segment with progressive reduction along the more distal segments. Among the principal, clear and basal cells of the distal cauda large intercellular spaces were observed, being filled with membrane remains, structures like myelin figures, vesicles, multivesicular bodies or flocculent material. The observation of these spaces among the epithelial cells of the distal cauda suggested that transcytosis occurred in the epididymal cauda of the Golden hamster, with possible transit of water and other substances from the lumen. Transcytosis possibly influenced the formation of the epididymis luminal microenvironment. From these observations it can be deduced that the caput and corpus regions of the epididymis were related to specific activities of spermatozoa maturation and the cauda, besides storing of spermatozoa, could be the main site to acquise of the fertilization ability / Doutorado / Anatomia / Doutor em Biologia Celular e Estrutural
36

Transport mechanism underlying the formation of microenvironment in rat efferent duct and epididymis. / CUHK electronic theses & dissertations collection

January 2001 (has links)
Leung Pak Heng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 163-189). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
37

Studies on the secretion of macromolecules by the mammalianepididymis, their interaction with spermatozoa and their roles insperm maturation

曾潤福, Tsang, Yun-fuk, Angus. January 1983 (has links)
published_or_final_version / Physiology / Doctoral / Doctor of Philosophy
38

Studies on the role of membrane conductance changes in electrolyte secretion and volume regulation in the cultured rat and human epididymal cells.

January 1993 (has links)
by Wai-on Fu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 88-95). / Chapter Chapter I --- Introduction --- p.1 / Chapter I .1 --- Structure and functions of the epididymis --- p.1 / Chapter I.2 --- Cellular mechanisms for electrolyte secretion --- p.3 / Chapter I.3 --- Second-messenger modulation of chloride secretion in epididymis --- p.5 / Chapter I.3.1 --- Cyclic AMP pathway --- p.5 / Chapter I.3.2 --- Ca2+ as second messenger --- p.6 / Chapter I.4 --- Pathophysiology of electrolyte transport in the epididymis --- p.6 / Chapter I.5 --- Objectives of the study --- p.9 / Chapter Chapter II. --- Materials and Methods --- p.10 / Chapter II. 1 --- Materials --- p.10 / Chapter II. 1.1 --- Culture media and enzyme --- p.10 / Chapter II. 1.2. --- Drugs --- p.10 / Chapter II. 1.3 --- Chemicals --- p.11 / Chapter II. 1.4. --- Animals and human tissue --- p.11 / Chapter II.2 --- Preparation of solutions --- p.12 / Chapter II. 3. --- Preparation of cultured cells --- p.12 / Chapter II.3 .1 --- Culture of rat epididymal epithelial cells --- p.12 / Chapter II.3.2 --- Cultured of human epididymal epithelial cells --- p.16 / Chapter II.4. --- Patch-Clamp technique --- p.21 / Chapter II.4.1 --- Electrode --- p.23 / Chapter II.4.2 --- Pulling of electrode --- p.23 / Chapter II.4.3 --- Coating of electrode --- p.23 / Chapter II.4.4 --- Polishing of the electrode --- p.24 / Chapter II.4.5 --- Filling of the electrodes --- p.26 / Chapter II.4.6 --- Mounting of Electrode to the Headstage Pipette Holder --- p.26 / Chapter II.4.7 --- Electrical Isolation --- p.28 / Chapter II.4.8 --- Vibration Isolation --- p.28 / Chapter II.4.9 --- "Formation of ""Giga-seal"" and Whole-cell configuration" --- p.28 / Chapter II.4.10 --- Correction for liquid junction potential --- p.30 / Chapter II.4.11 --- "Data Acquisition and Analyses," --- p.32 / Chapter II.4.12 --- Statistics --- p.34 / Chapter Chapter III. --- Results --- p.35 / Anion Secretion in human epididymal cells --- p.35 / Chapter III. 1 --- Whole-cell current in human epididymal cells --- p.35 / Chapter III. 2 --- Effect of adrenergic receptor blockers on whole-cell current --- p.38 / Chapter III.3 --- Effect of inhibitors of the cyclic AMP pathway --- p.42 / Chapter III.4 --- Effect of altering intracellular calcium concentration --- p.42 / Anion secretion in rat epididymal cells --- p.46 / Chapter III. 5 --- Effect of cAMP on whole cell C1- current in rat epididymis --- p.46 / Chapter III.6 --- Effect of ionomycin on whole cell C1- current --- p.53 / Chapter III.7 --- Differences between cAMP- and ionophore- dependent C1- current --- p.57 / Chapter III. 8 --- The swelling-induced whole-cell currents --- p.63 / Chapter III.9 --- The swelling-induced current was mainly C1- selective --- p.65 / Chapter III. 10 --- Anion selectivity of the swelling-induced C1- current --- p.68 / Chapter III. 11 --- Inhibition of the swelling-induced C1- conductance by anion channel blockers --- p.68 / Chapter III. 12 --- The role of Ca2+ and cAMP in swelling-induced C1- conductance --- p.74 / Chapter Chapter IV. --- Discussion --- p.79 / Signal transduction mechanism of adrenaline stimulated C1- current in human epididymal cell --- p.79 / Anion secretion in rat epididymal cell The role of Ca2+ and cAMP --- p.83 / Chapter Chapter V. --- Reference --- p.88
39

Signal transduction pathways involved in ATP-activated chloride conductance in rat epididymal cell. / CUHK electronic theses & dissertations collection

January 1996 (has links)
by Wen-Liang Zhou. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 125-144). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
40

Study of Inhibitory Effect of Epididymal Cres on Pc4/Pcsk4 Activity

Mishra, Priyambada 04 May 2011 (has links)
PC4/PCSK4 is the major Proprotein Convertase (PC) enzyme that plays a key role in mammalian fertilisation. It is detected in the acrosomal granules of round spermatids, acrosomal ridges of elongated spermatids and sperm plasma membrane overlying the acrosome with K-X-K/X-R as its preferred cleavage motif. Such motifs are present in male germ cell proteins ADAMs, proPACAP and proIGF-1/2 and these precursor proteins are processed most likely by PC4 during spermatogenesis, sperm maturation and sperm-egg interaction. For fertilization to occur, the mature sperm must penetrate the Zona Pelucida (ZP) and bind to the egg. Previously, PC4 null mouse sperm and wild type sperm treated with a specific PC4-inhibitor have shown to reduced abilities to penetrate the cumulus mass, bind to ZP and fertilize eggs. These findings suggest that sperm-PC4 plays an important role in fertilization and hence regulation of its activity is crucial for successful fertilization. But how PC4 activity is regulated in vivo is not yet clear. Recently, in epididymal fluid a serpin (serine protease inhibitor) called CRES has been described but the protease linked to this serpin in epididymis has not been identified. However in endocrine cells where CRES is also expressed, it inhibits PC2 enzyme. Thus based on localization and preliminary study, we propose that PC4 is the target enzyme for CRES in the reproductive tract. During sperm migration and storage in epididymis, sperm PC4 activity may be modulated by CRES so that premature sperm activation may not occur. Our data showed that CRES inhibits PC4 both in vitro (with IC50 in µM range) as well as ex vivo in human placenta trophoblast cell lines. Moreover CRES was found to be cleaved by PC4 suggesting a Serpin-Protease binding type of mechanism in the inhibition of protease activity. Taken together, we conclude that CRES regulates PC4 activity in reproductive tract crucial for mammalian fertilization.

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