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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

Good soldiers, good guys, and good parents : the meanings of donation and donated tissue in the context of the Danish donor sperm industry

Wheatley, Alison Louise January 2016 (has links)
Denmark is a major exporter of both anonymous and identity-release donor sperm worldwide, and is home to one the world's largest sperm bank networks. The country's legal framework allows for sperm donors to make the choice whether to be anonymous or to release their identity to potential offspring, in contrast to the majority of European countries which require either anonymity or identity-release donation. As such, it represents a chance for researchers to draw comparisons between donors who have explicitly made these different choices. This thesis draws on data from thirteen in-depth semi-structured interviews carried out with donors at a major Danish sperm bank. I suggest that neither the traditional ‘beer money for the weekend’ nor the currently-popular ‘wanting to help’ narrative of sperm donation tells the full story; the experiences of these donors cannot be expressed fully using an altruistic gifting model, but neither are they fully captured in terms of the capitalist exchange of labour; as ‘help’ or as ‘work’. Donor virility, and by extension masculinity, is represented through sperm quality and the discourse of “good sperm”, which then explicitly informs donor payment, complicating the relationship between donors’ embodied experience, their pride in their ‘product’ and the various ways in which semen as a substance is understood: “good sperm” could make a donor into a ‘good guy’ who could help with the falling national birth count, whereas sperm that was “bad” could be reframed as the product of donors’ lifestyles or as ‘good soldiers’ fighting against the freezing process. Donor accounts of sperm donation were also informed by the wider web of connections that are formed through the process of sperm donation: real, potential, or imagined connections between donor and offspring, donor and their imagined ‘good’ recipient, offspring and donor families, and donors and the wider Danish nation in terms of the production of so-called ‘Viking sperm’ and the extension of the ‘help’ discourse through the falling Danish sperm count.
2

A FUNCTIONAL, COMPARATIVE AND CLINICAL ANALYSIS OF SPERM-BORNE OOCYTE ACTIVATING FACTOR, PAWP

Aarabi, Mahmoud 01 October 2013 (has links)
Successful fertilization depends upon the activation of metaphase II arrested oocytes by sperm-borne oocyte activating factor (SOAF). Failure of oocyte activation is considered as the cause of treatment failure in a proportion of infertile couples. SOAF induces the release of intracellular calcium in oocyte which leads to meiotic resumption and pronuclear formation. Calcium release is either in the form of single calcium transient in echinoderm and amphibian oocytes or several calcium oscillations in ascidian and mammalian oocytes. Although the SOAF attributes are established, it is not clear which sperm protein(s) play such role. Sperm postacrosomal WW binding protein (PAWP) satisfies a developmental criteria set for a candidate SOAF. This study shows that recombinant human PAWP protein or its transcript acts upstream of calcium release and fully activates the amphibian and mammalian oocytes. Interference trials provided evidence for the first time that PAWP mediates sperm-induced intracellular calcium release through a PPXY/WWI domain module in Xenopus, mouse and human oocytes. Clinical applications of PAWP were further investigated by prospective study on the sperm samples from patients undergoing intracytoplasmic sperm injection (ICSI). PAWP expression level, analyzed by flow cytometry, was correlated to ICSI success rate and embryonic development. This study also explored the developmental expression of the other SOAF candidate, PLCζ in male reproductive system and its function during fertilization. Our findings showed for the first time that PLCζ most likely binds to the sperm head surface during epididymal passage and is expressed in epididymis. We demonstrated that PLCζ is also compartmentalized early in spermiogenesis and thus could play an important role during spermiogenesis. Detailed analysis of in vitro fertilization revealed that PLCζ disappears from sperm head during acrosome reaction and is not detectable during sperm incorporation into the oocyte cytoplasm. In conclusion, this dissertation provides evidence for the essential non-redundant role of sperm PAWP in amphibian and mammalian fertilization; recommends PAWP as a biomarker for prediction of ICSI outcomes in infertile couples; and proposes that sperm PLCζ may have functions other than inducing oocyte activation during fertilization. / Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2013-09-29 23:45:35.395
3

Infertilité "normale" vs infertilité "pathologique" : une opposition en question : normes et pratiques françaises de l'AMP face à l'infertilité féminine liée à l'âge. / "Normal" infertility vs. "pathological" infertility : opposition in question : French standards and practices of the AMP against age-related female infertility

Vialle, Manon 11 December 2017 (has links)
La croissance de l’infertilité féminine liée à l’âge dans les sociétés européennes et nord-américaines suscite une augmentation de demandes en matière d’assistance médicale à la procréation (AMP) et amène chaque société à s’interroger sur ses normes et pratiques. En France, cette question est un révélateur de la spécificité du modèle bioéthique qui encadre les techniques d’AMP, ainsi que de ses tensions et contradictions croissantes. La particularité de ce modèle est de se présenter comme strictement « thérapeutique » et de reposer sur l’opposition entre infertilité « normale » et infertilité « pathologique ». Cette opposition en nourrit une autre, à connotation plus morale, celle qui distingue une AMP légitime et une AMP dite « de convenance personnelle », légitimant un discours social et médical particulièrement conservateur et réactif face aux perspectives d’utilisation des techniques médicales dans le but de pallier l’infertilité féminine liée à l’âge.À partir de deux enquêtes, l’une auprès de professionnels de l’AMP et l’autre auprès de femmes confrontées à une infertilité liée à leur âge, cette thèse propose d’appréhender l’infertilité dans une démarche pragmatique, en s’inscrivant dans une approche relationnelle. Elle révèle ainsi que les règles d’accès à l’AMP en France et le discours social, reposant sur l’opposition entre les deux infertilités, s’appuient sur une vision trop étroite, simplifiée et au fond ininterrogée de l’infertilité elle-même. Notre recherche permet de mettre au jour l’existence de référents normatifs non pris en compte par ce modèle, qui s’avèrent pourtant centraux dans les pratiques des professionnels et des femmes. Elle ouvre ainsi vers une approche plus complexe de l’infertilité à la fois biologique, mais aussi et toujours sociale, relationnelle et temporelle. / Growth in age-related female infertility in European and North American societies raises demands for assisted reproductive technologies (ART) and leads each society to question its standards and practices. In France, this question reveals the specificity of the bioethics model that frames the techniques of ART, as well as its increasing tensions and contradictions. The particularity of this model is to present itself as strictly "therapeutic" and to rely on the opposition between "normal" infertility and "pathological" infertility. This opposition encourages one another, with a more moral connotation, that distinguishes a legitimate ART and an ART called "personal convenience", legitimizing a social and medical discourse that is particularly conservative and reactive in the face of prospects for the use of medical techniques for the purpose to mitigate female infertility related to age.Based on two surveys, one with ART professionals and the other with women facing age-related infertility, this thesis proposes to understand infertility in a pragmatic approach by adopting a relational approach. It thus reveals that the rules governing access to ART in France and social discourse, based on the opposition between the two types of infertilities, are based on a too narrow, simplified and, in the end, not taking into consideration the view of infertility itself. Our research makes it possible to discover the existence of normative referents not taken into account by this model, which are nevertheless central in the practices of professionals and women. This thesis opens up a more complex approach to infertility that is both biological, but also and always social, relational and temporal.
4

Conceiving a Feminist Legal Approach to Frozen Embryos: Exploring the Limitations of Canadian Responses to Disposition Disputes and Donor Anonymity

Carsley, Stefanie 21 November 2013 (has links)
This thesis advances a feminist critique of Canadian legal responses to disputes over frozen in vitro embryos and embryo donor anonymity. It argues that current laws that provide spouses or partners with joint control over the use and disposition of embryos created from their genetic materials, that mandate the creation of agreements setting out these parties intentions in the event of a disagreement or divorce and that protect donor anonymity without providing mechanisms to allow donors, recipients and donor offspring to voluntarily exchange information do not adequately account for the lived experiences of women who undergo in vitro fertilization treatment or who serve as embryo donors. This thesis provides recommendations for how Canadian laws and policies might better support the express objectives and intentions of Canadian federal and provincial statutes to protect the rights, interests and health of women who seek to build their families through assisted reproductive technologies.
5

Development of Assisted Reproductive Technologies for Endangered North American Salamanders

Marcec, Ruth Marie 12 August 2016 (has links)
Amphibians are key health indicator species and important sentinels for ecosystem health. With 32% of amphibians threatened with extinction, and an additional 25% without enough data on record to fully understand their status, amphibians are facing what is being called the Amphibian Extinction Crisis. Of caudate amphibians (salamanders/newts), 49.8% are threatened or endangered, making them currently the most threatened vertebrate taxa. As a result of the Amphibian Extinction Crisis, it is imperative that captive breeding facilities be established as a hedge against future amphibian extinctions. Unfortunately, captive assurance colonies face frequent failure due to lack of natural stimuli, which are necessary for amphibian breeding. Therefore, assisted reproductive technologies (ART) have been employed to reproduce endangered amphibians, increasing the success of captive assurance colonies worldwide. Over the last decade, a great deal of attention has been given to restoring anuran (frog/toad) populations through captive breeding, but little attention has been given to preservation of caudate species. Caudate amphibians are notoriously difficult to breed in captivity, thus it is crucial that ART be developed to help preserve endangered caudates sooner, rather than later. The following studies highlight some of the first attempts at developing ART protocols in caudate amphibians. Protocols were developed for: hormone induction of gamete production; cryopreservation of salamander sperm; and in vitro fertilization. These protocols were developed for the common, model species Ambystoma tigrinum in order to assure safety and efficiency for later application in endangered species.
6

Analysis of Oocyte Quality in the Rhesus Macaque (Macaca mulatta)

Nichols, Stephanie 18 May 2007 (has links)
Many primate populations face the threat of extinction due to habitat loss, intensive agriculture, hunting for meat, the pet trade and/or use in traditional medicines. An alternative approach to in situ conservation includes gene banking and the use of assisted reproductive technologies (ART), such as oocyte in vitro maturation (IVM) and in vitro fertilization (IVF). Although many of these 'high-tech' solutions have not yet been proven viable for pragmatic wildlife conservation, basic research and development of these emerging tools can provide necessary information needed to optimize these techniques and institute ART as a routine practice in conservation efforts. A severely limiting factor in the successful application of ARTs is the availability of mature developmentally competent oocytes. Oocyte maturation involves many nuclear and cytoplasmic factors, which can be affected by maturation conditions and female age. In vitro maturation does not have the same success rate across species studied. In primates especially, IVM oocytes exhibit reduced developmental capacity upon fertilization when compared to in vivo matured (IVO) oocytes. This study aimed to investigate possible causes of reduced developmental capacity of primate IVM oocytes using the rhesus macaque (Macaca mulatta) as a model. Research efforts included investigation of ovarian senescence, oocyte karyotype and spindle morphology, and establishment of an optimal sperm cryopreservation protocol for use in IVF. Histological examination of the rhesus ovary demonstrated an age-related pattern of follicle depletion similar to that described in the human ovary. Oocyte karyotype analysis revealed a significant effect of IVM on the frequency of hyperhaploidy. In addition, immunostaining and confocal microscopy demonstrated a significant increase of anomalous chromosome congression on the oocyte metaphase II spindle equator in relation to IVM and donor female age. These results indicate that IVM can produce serious, if not lethal consequences for embryo development. This study presents baseline data on ovarian aging in the rhesus macaque and aspects of nuclear maturation during macaque IVM that may contribute to the design of primate oocyte recovery plans. Implementation of either of two sperm cryopreservation methods originally developed for rhesus and vervet monkeys will aid future investigation of the developmental capacity of IVM oocytes.
7

Pagalbinių apvaisinimo būdų taikymo etinės problemos pacientų požiūriu / Patients view of ethical problems in assisted reproductive technologies use

Simonavičienė, Aušra 03 August 2007 (has links)
Darbo tikslas. Išanalizuoti pagalbinių apvaisinimo būdų taikymo etines problemas pacientų požiūriu. Uždaviniai. Ištirti ir palyginti vaisingų ir nevaisingų šeimų požiūrį į pagalbinius apvaisinimo būdus; Nustatyti etines problemas, kylančias nevaisingoms šeimoms, naudojant pagalbinius apvaisinimo būdus; Įvertinti nevaisingų šeimų požiūrį į pagalbinių apvaisinimo būdų įstatyminę bazę. Tyrimo metodika. Anoniminė anketinė apklausa. Tirtos dvi respondentų grupės: nevaisingi asmenys (vaisingumo asociacijos nariai, n=93) ir vaisingi asmenys (besilaukiančios moterys, n=146). Rezultatai. Didžioji dalis respondentų yra girdėję apie pagalbinius apvaisinimo būdus ir jų taikymą. Vaisingi asmenys linkę pritarti įvairiems IVF taikymo apribojimams (amžiaus riba, IVF tik susituokusioms poroms ir pan.), vaisingumo sutrikimų turintys asmenys linkę naudotis PAB be jokių apribojimų. Nevaisingi žmonės pritaria embrionų užšaldymui, donorystei bei surogatinei motinystei, siekdami išnaudoti visus įmanomus būdus pasiekti norimo nėštumo. Nevaisingų asmenų nuomone, būtiname DA įstatyme privalo atsispindėti embrionų šaldymas, donorystė bei procedūrų kompensavimo tvarka. Išvados. 84,9 proc. visų tyrime dalyvavusių respondentų mano, kad nevaisingumas yra liga; 88,7 proc. visų respondentų yra girdėję apie pagalbinius apvaisinimo būdus. Abiejų grupių respondentai pritaria tiek in vivo, tiek in vitro procedūroms. Nevaisingos šeimos perteklinių embrionų sukūrime, jų šaldyme, spermos ar kiaušialąsčių... [toliau žr. visą tekstą] / Aim of the study. To analyse the patient‘s view of ethical issues in assisted reproductive technologies use. Objectives. To investigate and compare the fertile and infertile person‘s view of assisted reproductive technologies; To identify an ethical problems arising for infertile persons from assisted reproductive technologies use; To evaluate infertile person‘s view of assisted reproductive technologies legislative base. Methods. Anonymous questionnaire survey. Inquired two groups of respondents: infertile persons (members of Fertility Association, n=93) and fertile persons (pregnant women, n=146). Results. Most of respondents have heard about the use of assisted reproductive technologies. Fertile persons are minded to agree with various limitations of IVF use (age limit, IVF only for married couples, etc.), infertile persons prefer to use ART without any restrictions. Infertile people accept embryos cryopreservation, use of donors and surrogate motherhood, seeking to use all possibilities in order to receive pregnancy. According to infertile people opinion, new ART law is mandatory and must cover embryo cryopreservation, use of donors and reimbursement of procedures. Conclusions. 84.9 % of all respondents thinks, that infertility is a disease; 88.7 % of all respondents have heard about assisted reproductive technologies. Respondents of both groups approves in vivo and in vitro procedures. Infertile persons do not see serious ethical issues in creation of spare embryos... [to full text]
8

Impact des facteurs maternels et paternels sur les résultats de FIV / ICSI et investigations génétiques des spermatozoïdes d'hommes infertiles / Impact of maternal and paternal factors on the results of IVF / ICSI and genetic investigations on the spermatozoa of infertile men

El Fekih, Sahar 20 December 2018 (has links)
L’infertilité concerne 8 à 12% des couples en âge de procréer. Face à ce problème, des prises en charge médicales peuvent être proposées comme la fécondation in vitro (FIV) et l’injection intracytoplasmique de spermatozoïde (ICSI). Toutefois, le taux d’échec de ces techniques reste relativement élevé. Dans la première partie, l’impact des facteurs maternels et paternels sur les résultats de 194 cycles de FIV et 586 cycles d’ICSI a été étudié. L’âge maternel, le nombre d’ovocytes ponctionnés et matures influencent principalement les résultats. Ni l’âge paternel ni les paramètres spermatiques (numération et mobilité) ne s’associent significativement à l’échec des techniques d’assistance médicale à la procréation (AMP). Seule la morphologie du spermatozoïde injecté a une influence sur la fécondation en ICSI. En deuxième partie, l’apoptose, la fragmentation de l’ADN et le contenu chromosomique avant et après tri cellulaire à l’aide des microbilles magnétiques ont été étudiés chez des hommes avec un taux de fragmentation de l’ADN spermatique anormal et chez des hommes porteurs d’une anomalie chromosomique constitutionnelle. Une diminution significative des spermatozoïdes apoptotiques avec un ADN fragmenté et chromosomiquement déséquilibrés a été observée. Le tri cellulaire aboutissant à une sélection de spermatozoïdes de meilleure qualité pourrait s’avérer une méthode de référence pour l’AMP. Dans une troisième partie, un protocole fiable a été élaboré pour étudier le transcriptome des spermatozoïdes. La mise au point de ces technologies permettra de mieux comprendre les causes d’échec des techniques d’AMP et ainsi améliorer leur taux de réussite. / Infertility concerns 8-12% of couples of reproductive age. Various medical treatments such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are available to address this problem. However the rate of failure of these procedures remains relatively high.In the first part of this work the impact of maternal and paternal factors on the results of 194 IVF cycles and 586 ICSI cycles was studied. Results are mainly affected by maternal age, the number of oocytes retrieved and the number of mature oocytes collected. Neither paternal age nor spermatic parameters (number and mobility) are significantly associated with the failure of Assisted Reproductive Technologies (ART). Only the morphology of the sperm injected during ICSI influences fertilization rate.In the second part of this work apoptosis, DNA fragmentation and the chromosomal content before and after cell sorting with magnetic micro beads were studied in men with an abnormal level of sperm DNA fragmentation and in men with a constitutional chromosome abnormality. A significant decrease of apoptic spermatozoa with fragmented DNA and chromosome imbalance was observed. Thus cell sorting leading to the selection of better quality spermatozoa could become a reference method for ART.In a third part of the work a reliable protocol for the study of spermatic transcriptomes is designed.The development of these technologies will lead to a better understanding of the underlying causes ofART failure and thus increase the success rate.
9

The constitutional and contractual implications of the application of chapter 19 of the Children's Act 38 of 2005

Lewis, Samantha Vanessa January 2011 (has links)
In this research, I carefully and coherently examine Chapter 19 of the Children's Act 38 of 2005 as the first legislation to afford surrogate motherhood agreements legal recognition in South Africa. I argue that the application of Chapter 19 imposes a number of unwarranted limitations on several of the constitutional rights of the parties to a surrogacy agreement. In addition, I propose that Chapter 19 is not in accordance with the principal of the best interests of the child. I examine the history of surrogate motherhood in South Africa and establish that, prior to the enactment of Chapter 19, no legislation expressly afforded surrogate motherhood agreements legal recognition. Hence, prior to the enactment of Chapter 19, parties who entered surrogacy agreements could, first, not rely on the agreement to enforce contractual obligations, and secondly, the legal positions of the parties to the agreement were uncertain. Thirdly, a child born of a surrogacy agreement was seen as the child of the surrogate mother and not of the commissioning parents.
10

The constitutional and contractual implications of the application of chapter 19 of the Children's Act 38 of 2005

Lewis, Samantha Vanessa January 2011 (has links)
In this research, I carefully and coherently examine Chapter 19 of the Children's Act 38 of 2005 as the first legislation to afford surrogate motherhood agreements legal recognition in South Africa. I argue that the application of Chapter 19 imposes a number of unwarranted limitations on several of the constitutional rights of the parties to a surrogacy agreement. In addition, I propose that Chapter 19 is not in accordance with the principal of the best interests of the child. I examine the history of surrogate motherhood in South Africa and establish that, prior to the enactment of Chapter 19, no legislation expressly afforded surrogate motherhood agreements legal recognition. Hence, prior to the enactment of Chapter 19, parties who entered surrogacy agreements could, first, not rely on the agreement to enforce contractual obligations, and secondly, the legal positions of the parties to the agreement were uncertain. Thirdly, a child born of a surrogacy agreement was seen as the child of the surrogate mother and not of the commissioning parents.

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