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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.
71

The Politics of Being an Egg “Donor” and Shifting Notions of Reproductive Freedom

Dedrick, Elizabeth A 31 March 2004 (has links)
As an Assisted Reproductive Technology (ART) that has been available for over twenty years, the transfer of healthy eggs from a presumably fertile woman into the womb of a woman diagnosed as infertile has become a common part of the landscape of human reproduction in the United States. Yet the general societal acceptance of this practice commonly known as "egg donation" oversimplifies the complex medical, ethical, and societal issues ignited by its use. In light of the limited critical discussions presently occurring about egg transfer, I will interrogate some of the silences and more ambiguous issues invoked by its practice. By giving particular attention to the often ignored experiences of egg "donors," I will analyze the popularly used discourses around this ART. In doing so, I will investigate the ways in which egg donation complicates notions of altruism, autonomy, and exploitation as well as what consequences this has for women's reproductive freedoms as envisioned by many U.S. feminists.
72

The ethical implications of human ectogenesis

Coleman, Stephen,1968- January 2001 (has links)
Abstract not available
73

The in vitro produced cow embryo : factors affecting development and metabolism

Steeves, Tracey Elizabeth, 1968- January 2000 (has links)
Abstract not available
74

Ovarian xenografting for the conservation of endangered species

Snow, Melanie Jennifer January 2003 (has links)
Abstract not available
75

Examination of the Role of p53 in Embryo and Sperm Function

Gunay, Nida January 2007 (has links)
Master of Science in Medicine (by research) / Assisted reproductive technologies (ARTs) are very efficient in producing embryos, however many of these embryos have poor viability. No more than 50% of IVF embryos complete preimplantation development (Hardy et al. 2001). The poor viability is manifested as a reduced rate of cell proliferation and increased rates of apoptosis in the early embryo, resulting in high rates of embryo mortality (Hardy et al. 2001). The reduced viability occurs as a response to a range of cellular stressors that are a consequence of embryo culture (Hardy et al. 2001). The stress of culture disrupts some survival signalling pathways, metabolism of substrates and induces redox stress (Hardy et al. 2001). The cellular stress sensor p53 is expressed in the early embryo but is normally kept at very low levels (Li et al. 2005). This latency may be breached in IVF embryos following culture of zygotes in vitro for 96 hours, resulting in the up-regulation and nuclear accumulation of p53 (Li et al. 2005). Activation of the p53 stress-sensing pathway in the early mouse embryo by culture in vitro causes a marked loss of their developmental competence (Li et al. 2005). This study aimed to establish whether benefits could be obtained by culturing mice IVF embryos in the presence of p53 protein inhibitors. IVF zygotes were cultured individually in 10µl drops of 1.25, 2.5, 5 or 10µM Pifithrin-a (PFTa) in 0.05% DMSO for 96 hours. On day 5 the development stage was assessed. Embryos reaching the blastocyst stage were fixed and stained with Hoechst 33342 for total cell count and the proportion of nuclei with normal and abnormal morphology. There was an increase in the blastocyst rate, total cell count and the proportion of nuclei in a blastocyst with normal nuclei in 10µM-treated embryos. This study also aimed to determine whether benefits could be obtained by incubating mouse IVF sperm with p53 protein inhibitors during IVF. IVF sperm was treated with 1.25, 2.5, 5 or 10µM of PFTa in 0.05% DMSO during incubation with oocytes for 6 hours. Resulting zygotes were cultured for 96 hours individually in 10µl drops of MODHTFM. On day 5 the development stage was assessed. Embryos reaching the blastocyst stage were fixed and stained with Hoechst 33342 for total cell count and the proportion of nuclei with normal and abnormal morphology. There was a reduction in the proportion of fragmented nuclei in blastocysts derived from 1.25 and 10µM-treated sperm. 10µM treated sperm increased the total cell count, the proportion of normal nuclei in a blastocyst and the blastocyst development rate. IVF sperm incubated with 1.25µM PFTa during insemination of oocytes increased the fertilisation rate. Another aim of this study was to establish whether p53 siRNA could inhibit p53 mRNA in mice IVF embryos and if so, whether this would improve embryo viability in culture. IVF zygotes were transfected with 15nM p53 small inhibiting RNA (siRNA) and 0.8% Oligofectamine Reagent immediately, 24 h, 48 h and 72 h after IVF then cultured individually in 10µl drops of MOD-HTFM for a total of 96 hours. On day 5 the blastocyst rate was assessed and immunofluorescence performed probing for p53. There was no significant reduction in p53 expression and no improvement in blastocyst rate at any of the transfection times. However, there was a decrease in the proportion of nuclei which expressed p53 when p53 siRNA was transfected 72 hours after IVF. Also, it was determined that siRNA was efficiently being delivered into the preimplantation embryo with Oligofectamine Reagent. Lastly, this study aimed to determine whether mice sperm with p53 gene deletions have a selective advantage in fertilising the oocyte compared to their wild-type counterparts. p53+/- males were mated with p53+/+ females and the resulting zygotes genotyped after 24 hours of culture. More than 50% of offspring had a p53+/+ genotype. There was no selective advantage for p53 null sperm to fertilise the oocyte, there was actually a disadvantage. The selective disadvantage for p53 null sperm to fertilise the F1 hybrid oocyte in IVF compared to its wild-type counterparts may imply that p53 null sperm are not as viable and may have a survival disadvantage. The reduction in fertility of p53 null sperm in vitro infers that p53 function may be important for the fertility of the mouse sperm in vitro. The results of this thesis could establish means of improving human embryo viability in ART, some examples being P53 protein inhibition in preimplantation embryos during culture prior to transfer to the uterus, or P53 protein inhibition in IVF sperm. The use of the new technology, p53 siRNA was not effective in inhibiting p53 expression, although the build-up experiments determined that siRNA is efficiently delivered into the preimplantation embryo with Oligofectamine Reagent. The demonstration that p53 null sperm has a selective disadvantage in fertilising the oocyte compared to their wild-type counterparts does not indicate a positive selection pressure for naturally occurring mutations to this gene. And so, there is no concern regarding the genetic and epigenetic risks to progeny arising from assisted reproductive technologies with respect to sperm.
76

The ethics of preimplantation genetic diagnosis

Thakur, Sanjay, n/a January 2006 (has links)
Preimplantation genetic diagnosis is a technique used in the field of assisted reproduction. The technique is applied to embryos that have been created in vitro, in order to facilitate the selection of embryos according to particular genetic parameters. The use of preimplantation genetic diagnosis by prospective parents at high risk for having a child affected by a genetic disorder has facilitated the birth of unaffected children. Preimplantation genetic diagnosis has already been used for other purposes, such as screening for gender, and could in principle be used to screen for a wide range of genetic traits. The aim of this thesis is to provide good answers to the ethical questions provoked by the advent and continuing development of preimplantation genetic diagnosis. The thesis is divided into four parts. Part One provides a brief overview of the science of genetic selection. Part Two is centred on a discussion of two ethical principles. The principle of procreative liberty is based upon the idea that acts of interference in the reproductive lives of others should be avoided unless there is good justification for such acts. The principle of procreative beneficence is based upon the idea that prospective parents should select the child, of the possible children they could have, who is expected to have the best life. I will argue that the principle of procreative liberty should be applied to acts of interference in individuals� freedom to use preimplantation genetic diagnosis, while the principle of procreative beneficence should be applied to acts of selecting children. In Part Three, I will endorse a position that accords embryos a relatively low moral status, reject the arguments of the disability rights critique, argue that the eugenic aspects of preimplantation genetic diagnosis do not warrant much concern, and develop a framework for critically evaluating slippery slope arguments. Finally, in Part Four, specific applications of preimplantation genetic diagnosis will be examined in detail. Although each application raises unique ethical questions, this thesis aims to demonstrate that the consistent application of the principles and preliminary conclusions developed in Parts Two and Three provides the best means for determining how PGD should be used and which uses should be restricted.
77

Biopsychosocial associates of infertility related distress and treatment outcomes.

Mahajan, Neha Naresh January 2008 (has links)
The experience of difficulties in conception, the diagnosis of infertility and its treatment are frequently associated with anxiety and overall distress. However, current understanding regarding the determinants of variability in the levels of distress among women undergoing infertility treatment is limited; and the evidence of the significance of distress as a risk factor for assisted conception following IVF/ICSI is inconsistent. The thesis addressed both these issues. Overall the thesis is informed by the biopsychosocial model of health and illness. Four studies were conducted. The data was collected in three IVF clinics in India. A consecutive sample of 85 infertile women about to commence IVF/ICSI cycle was recruited in the project at cycle baseline and followed through one treatment cycle. The first two studies examined this sample of women at baseline to identify the biopsychosocial factors associated with infertility related distress. The first study examined the degree of cognitive–behavioural adjustment to infertility, its treatment and treatment related eventualities, while the second study focused on the factors associated with affective aspects of infertility related distress such as increase in negativity and decrease in positivity. The third study examined the pattern of change in stress operationalized in terms of changes in Affect and State Anxiety in a sample of 74 infertile women during an IVF/ICSI cycle. The final study developed a prognostic model for evaluating the unique contribution of baseline distress as well as treatment related stress in estimating the odds of pregnancy following IVF based on a consecutive sample of 73 women. Collectively, the first two studies indicate that at the outset of the IVF/ICSI cycle, some women are more prone to distress than others, and that this variability is associated with their intrapersonal, interpersonal and sociodemographic attributes. These two studies have identified a set of protective and vulnerability factors related to cognitive-behavioural and affective aspects of distress. The last two studies clearly indicate that the level of distress tends to rise during the treatment among the majority of infertile women. The rising trend continued to be significant even after controlling for variables known to somewhat influence infertility related distress such as age, education, occupation, employment, financial burden and etiological factors. Further, a prognostic model is developed that proposes that both baseline level of stress and treatment stress make a unique contribution in defining the odds of pregnancy outcome for the patients. In short the thesis clearly brings out the case for integrating psychosocial care with the routine medical interventions for infertility. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325419 / Thesis (Ph.D.) - University of Adelaide, School of Psychology, 2008
78

The regulation of research involving human embryos and cloning in the United Kingdom and Australia

Allan, Sonia Marie January 2009 (has links)
This thesis analyses the nature, rationale, and implementation of United Kingdom and Australian regulation of research involving human embryos and cloning using legal materials, other documents and qualitative interviews with researchers, practitioners and regulators. It considers how law-makers have decided upon what to regulate and where to draw the line between permissible and prohibited activities, and the type of regulatory design strategies and enforcement approaches adopted in each jurisdiction (the ‘how to regulate’ question). It is argued that both jurisdictions have effectively decided upon permissible and prohibited activities as a result of thorough public consultation, research, reviews and the parliamentary process, and have appropriately balanced competing rationales for regulation. However, the type of regulation used in relation to those who are licensed to research in this area is unsuitable due to an over-emphasis on deterrence and the authoritarian approach taken by the regulatory bureaucracies. The central thesis is that a responsive regulatory system for licence-holders should be adopted. It is proposed that such a system would maintain the top level ‘command and control’ design strategies and deterrence approaches present in the current regulatory systems for breaches of legislation by non-licence holders and serious breaches by licence holders. However, greater use of co-regulatory design strategies and cooperative, educative and persuasive enforcement approaches should be used for regulating licensed research activities.
79

Access to Assisted Human Reproduction (AHR) Services for Trans People in Ontario

James-Abra, Sarah 20 November 2012 (has links)
There is a dearth of research that explores the lives and experiences of trans-identified parents. The goal of this study was to explore the experiences of trans people who sought or accessed AHR services in Ontario between 2007 and 2010. Qualitative data that was collected from 7 qualitative interviews with 9 trans people and their partners was analyzed for the present analysis. Results from this study indicate that AHR providers do not possess sufficient knowledge about trans people, trans identities and trans lives to adequately address the needs of trans service users. Specific provider practices that trans people experienced as being unhelpful are illuminated and implications for improving clinical practices are discussed.
80

Access to Assisted Human Reproduction (AHR) Services for Trans People in Ontario

James-Abra, Sarah 20 November 2012 (has links)
There is a dearth of research that explores the lives and experiences of trans-identified parents. The goal of this study was to explore the experiences of trans people who sought or accessed AHR services in Ontario between 2007 and 2010. Qualitative data that was collected from 7 qualitative interviews with 9 trans people and their partners was analyzed for the present analysis. Results from this study indicate that AHR providers do not possess sufficient knowledge about trans people, trans identities and trans lives to adequately address the needs of trans service users. Specific provider practices that trans people experienced as being unhelpful are illuminated and implications for improving clinical practices are discussed.

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