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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.
121

The Effect of Fluoxetine on Ovulation in Rabbits

Barry, Amanda 04 November 2019 (has links)
No description available.
122

Effects of clomiphene citrate on the expression of kisspeptin dynorphin A and neurokinin B in female Sprague-Dawley rats

Fourie, Christle January 2016 (has links)
Clomiphene citrate (CC) is the leading treatment for women with anovulatory infertility. The precise mechanism of action of the drug on the hypothalamic-pituitary-gonadal (HPG) axis has yet to be determined. Neurons expressing kisspeptin, neurokinin B (NKB) and dynorphin A (Dyn), collectively called KNDy neurons, in the arcuate nucleus (ARC) of the hypothalamus have been shown to play an integral role in the estradiol (E2) feedback pathways of the reproductive system in mammals. KNDy neurons are found in the ARC and the anteroventral periventricular nucleus (AVPV) in humans but have been predominantly reported to not express NKB and Dyn in rodents. The axons of these neurons project to the medial eminence (ME) in the region where the gonadotropin-releasing hormone (GnRH) terminals and fibres are located. It was hypothesised that CC upregulates the gene expression of kisspeptin and neurokinin B while down-regulating the gene expression of dynorphin A which results in a leutenizing hormone surge and an increase in oestradiol which causes ovulation. This was a randomized experiment which included 18 female Sprague-Dawley rats in which the aim was to analyse the expression of kisspeptin, NKB and Dyn in the ARC and the AVPV as well as blood plasma levels of oestradiol and leutinizing hormone (LH) in female rats after CC administration. Six of the rats constituted the control group that received a vehicle solution. The second group of 6 rats received the intervention in the form of CC and the third group of six rats received CC as well as p234-penetratin, a kisspeptin antagonist (KpA). The mRNA expression of the KNDy genes were analysed using real-time quantitative polymerase chain reaction (qPCR) and the plasma levels of E2 and LH were analysed by enzyme-linked immunosorbant assays (ELISA). ELISA results show that the E2 concentration in the group that received CC plus KpA was found to be marginally lower than that of the control group but there was no significant difference between the E2 concentrations of the control group and the group that received only CC. The LH concentration in the group that received CC plus KpA was significantly higher than both other groups but again, there was no significant difference between the LH concentration control group and the group that only received CC. The qPCR showed that in the AVPV, the kisspeptin expression of the CC group and the CC plus KpA groups are marginally higher than that of the control group. Conversely, the Dyn expression of the CC group and the CC plus KpA groups are marginally lower than that of the control group in the AVPV. There were no significant differences in NKB expression across the three groups. In the ARC, there were no significant differences in kisspeptin or Dyn expression across the groups. The NKB expression of the CC group was marginally lower than that of the control and there was no significant difference between the CC plus KpA group and the control group. In summary, CC appears to have a marginal effect on the kisspeptin and Dyn mRNA via the positive feedback systems in the rat AVPV as well as a significant decrease of NKB mRNA via the negative feedback systems in the ARC. To increase the validity of similar future studies, higher sample sizes, different drug administration doses, possibly more precise surgical techniques and more accurate age determination methods or ovariectomised rats could be used. / Dissertation (MSc)--University of Pretoria, 2016. / Physiology / MSc / Unrestricted
123

Effect of Platelet Activating Factor on Embryonic Development and Implantation in the Mouse

Fukuda, Aisaku I., Breuel, Kevin F. 01 January 1996 (has links)
Platelet activating factor (PAF) was administered to female mice in order to investigate its effect on ovulation rate and on oocyte quality including their in-vitro embryonic development, implantation and uterine receptivity. In experiment 1, 4-week-old female mice were assigned to receive PAF or phosphate buffered saline for 4 consecutive days. On the second day of this treatment, pregnant mares' serum gonadotrophin was administered and human chorionic gonadotrophin (HCG) 48 h later, after which copulation occurred. Oocytes were collected on the following day and evaluated. The mean number of oocytes and zygotes (two pronuclear stage embryos) recovered from the PAF-treated group was not diffferent from the control group (31 versus 27), but the proportion of zygotes was higher in PAF-treated group than in controls (83 versus 68%, P < 0.05, PAF versus controls). Although the rate of in-vitro first cleavage was not different in the two groups (82 versus 69% respectively), hatching was higher in the PAF-treated group than control mice (99 versus 83%, P < 0.01). In experiment 2, the in-vitro developed blastocysts from experiment 1 were transferred into the uterus of day 3 pseudopregnant PAF-treated or control recipients. Three different combinations of intrauterine transfer were performed; PAF embryo to control recipient (PAF → C: n = 19), control embryo to PAF recipient (C → PAF: n = 19), and control embryo to control recipient (C → C: n = 22). Implantation and abortion were assessed on day 19 post-transfer. The implantation rate of C → PAF (23.7%) was lower than C → C (31.1%, P < 0.05), but was not different from PAF → C (31.2%). Further, C → PAF showed a higher abortion rate per embryo (29.6%) than PAF → C (12.7%, P < 0.05), but was not different from C → C (24.4%). In the present study, PAF administration enables females to produce oocytes with a higher potential for fertilization, in vitro development and implantation, but has a detrimental effect on uterine receptivity to embryos.
124

Aspirin Dose Dependently Inhibits the Interleukin-1β-Stimulated Increase in Inducible Nitric Oxide Synthase, Nitric Oxide, and Prostaglandin E<sub>2</sub> Production in Rat Ovarian Dispersates Cultured in Vitro

Carnovale, David E., Fukuda, Aisaku, Underhill, Derek C., Laffan, John J., Breuel, Kevin F. 18 April 2001 (has links)
Objective: Determine if aspirin inhibits the IL-1β-stimulated expression of inducible nitric oxide synthase (iNOS), nitric oxide (NO), and prostaglandin E2 (PGE2) in rat ovarian dispersates cultured in vitro. Design: Prospective, controlled in vitro study. Setting: Academic research laboratory. Animals: Ovaries collected from immature rats. Intervention(s): Ovaries were collected from immature rats and enzymatically dispersed. Ovarian dispersates were placed into plates containing media alone or media supplemented with IL-1β (100 U/mL) and varying concentrations of aspirin (0, 1, 3, 5 and 10 mM). Ovarian dispersates were cultured in a humidified environment of 5% CO2 in air at 37°C for 24 or 48 hours. Main Outcome Measure(s): Twenty-four- and 48-hour iNOS, nitrite (a stable metabolite of NO), and PGE2 levels were determined from ovarian dispersates cultured in vitro. Result(s): Administration of IL-1β increased nitrite and PGE2 levels over that observed in the control group after culture of ovarian dispersates for 24 and 48 hours. Aspirin dose dependently reduced the IL-1β-stimulated increase in nitrite production from ovarian dispersates after culture for 24 and 48 hours. Aspirin completely (24 hours) or dose dependently (48 hours) prevented the IL-β-stimulated increase in PGE2. Coadministration of IL-1β and aspirin (10 mM) attenuates IL-1β-stimulated iNOS expression after culture for 24 and 48 hours. Conclusion(s): Aspirin significantly inhibits the IL-1β-stimulated expression of iNOS, NO, and PGE2 in ovarian dispersates cultured in vitro.
125

Correlates of completion rate and question comprehension for a multi-ethnicity online study of ovulation and menstruation health

Williams, Anna Sophia 25 July 2018 (has links)
BACKGROUND: Polycystic ovary syndrome (PCOS), a diagnosis of exclusion, is considered the most common endocrinopathy in females of reproductive age. Current cohorts of individuals with PCOS exist but are limited, specifically in racial/ethnic diversity, due to the complexity of multiple choice survey questions and difficulty to obtain data. METHODS: After examining existing cohorts and their questionnaires, an online survey was designed specifically to assess PCOS characteristics in a diverse population. The survey was field tested for cognitive understanding and usability in a diverse population, with respect to race/ethnicity and education. After cognitive testing, the survey was launched online and participants were recruited to complete the survey. Survey completion rates by level of education, race/ethnicity, and birthplace were established by determining the proportion of participants in each subgroup to complete the entire survey. We also looked at the average percentage of the survey participants in each subgroup completed before discontinuing the survey. Univariate regression analyses were performed to evaluate these results. Question comprehension was determined by evaluating all survey questions by length and complexity. The survey question asking participants to report their typical menstrual cycle length (MCL) was selected to assess participants’ question comprehension. Responses that fell outside of the normal range for MCL were examined and those that may have been inaccurate were isolated. Level of education and birthplace reported by participants who may have responded to the MCL question inaccurately were noted and assessed collectively. RESULTS: Two-hundred and forty-eight participants, aged 18-53 years, began the survey between August 9, 2017 and October 23, 2017. Of these participants, 71.7% identified as White; 11.7% as Hispanic, Latina, or of Spanish Origin; 12.6% as Black or African American; 13.2% as other races/ethnicities; and 9.2% as more than one race/ethnicity. Of the participants with some high school education, a high school diploma, or a GED, 74% completed the entire survey; of those with some college education or a 2-year degree, 81% completed the entire survey; and of those with a 4-year college degree or more, 90% completed the entire survey. On average, participants with a high school education completed 86% of the survey before discontinuing; those with some college education completed 91% of the survey before discontinuing; and those with a college degree or more completed 95% of the survey before discontinuing. Of the participants who identified as White, 92% completed the entire survey; of those who identified as Hispanic, Latina, or of Spanish Origin, 68% completed the entire survey; and of those who identified as Black or African American, 70% completed the entire survey, with statistical significance (p = 0.002). On average, participants who identified as White completed 96% of the survey before discontinuing; those who identified as Hispanic, Latina, or of Spanish Origin completed 82% of the survey before discontinuing; and those who identified as Black or African American completed 86% of the survey before discontinuing, with statistical significance (p = 0.002). Of the participants who were born in the United States, 92% completed the entire survey, and of the participants who were not born in the United States, 66% completed the entire survey, with statistical significance (p < 0.0001). On average, participants who were born in the United States completed 96% of the survey before discontinuing and participants who were not born in the United States completed 81% of the survey before discontinuing, with statistical significance (p < 0.0001). When asked to report their typical MCL, 66 participants (28.1%) responded with irregular answers and 20 (8.5%) may have responded inaccurately. Of these 20 participants, 18 (90%) completed at least some amount of college and 16 (80%) were born in the United States. DISCUSSION: This pilot study succeeds in establishing a cohort that is more racially/ethnically diverse than existing cohorts of individuals with PCOS. In order to gather more information on the ways in which PCOS manifests across different groups, future recruitment efforts ought to be more targeted towards individuals belonging to different racial/ethnic groups and socioeconomic statuses. Additionally, the baseline survey and future modules can be made more accessible to diverse groups through language translation. Furthermore, the addition of a menstrual cycle tracker component to the survey may increase the accuracy of information on participants’ menstrual cycle patterns.
126

Application of Hough transformation to detect ovulatory patterns in cervical mucus images

Wang, Shiliang 01 January 1989 (has links)
A microcomputer system called ovulocomputer is proposed. The system is used to predict and detect ovulation of women. It will use image processing and analysis, pattern recognition theory, spectrophotometry, ionometry and conductometry to measure various physical and chemical properties of cervical mucus that are related to blood hormone levels. The functions and characteristics of cervical mucus are introduced in this thesis. Among them, the identification of cervical mucus images, named the ferning test, and related features, are well described. A new idea, called ferning test automation, which has been neither proposed nor developed before, is presented and explained in detail in this thesis.
127

The association between prostaglandins and the plasminogen activator/plasmin system in the porcine ovulatory process /

Grant, Gerald F. January 1993 (has links)
No description available.
128

Studies on follicular development and ovulation in cattle and swine.

Downey, Bruce R. January 1981 (has links)
No description available.
129

Understanding the role of lifetime ovulations on ovarian cancer risk across the spectrum of risk

Garofalo, Diana January 2023 (has links)
Ovarian cancer is the fifth most common cause of cancer death in females and the most lethal gynecologic cancer. Globally, an estimated 240,000 people are diagnosed with ovarian cancer each year, with 22,530 new cases in the United States in 2019. Parity, oral contraceptive use, and lactation are protective, while early menarche, late menopause, and nulliparity have opposite effects. The “incessant ovulation” theory has thus emerged, in which a higher number of ovulations may be a cause of epithelial ovarian cancer (EOC). However, the mechanisms of this theory are unknown; one possibility is that the chance of acquiring a cancer-initiating pathogenic variant increases with each ovulatory cycle because of a microenvironment that promotes DNA damage. In this dissertation, we aimed to leverage genetic epidemiologic data to test this potential mechanism by evaluating the presence of gene-environment interaction between DNA repair capacity (measured through the presence of pathogenic variants in DNA repair genes) and lifetime ovulatory years (LOY). In the first aim of this dissertation, we conducted a systematic review and meta-analysis, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, to formally evaluate the strength of evidence and to generate summary point estimates for the association between LOY and EOC. We then executed two analytic aims to evaluate if the presence of pathogenic variants in DNA repair genes exacerbated the increase in ovarian cancer risk associated with LOY. In Aim 2, we evaluated interaction on the additive scale in the United Kingdom (UK) Biobank through use of a novel DNA repair capacity score developed in this dissertation, measured by quantifying the number of pathogenic variants present per individual from a list of 163 DNA repair genes, using whole exome sequencing (WES) data. In Aim 3, we evaluated the presence of interaction between pathogenic BRCA1/2 status and LOY in the Breast Cancer Family Registry (BCFR), a cohort enriched for familial risk. In both empirical aims, we assessed the presence of interaction on the additive scale using the relative excess risk due to interaction (RERI) formula. We compared results across the two empirical aims. We found the relationship between lifetime ovulations and ovarian cancer risk to be consistent and replicable in the published literature. In pooled estimates from 22 published studies, a one-year increase in LOYs was associated with a 4% (3-6%) increased risk of ovarian cancer and those with a high number of ovulations (compared to low LOYs) had a 2.15-fold (95% CI 1.82, 2.54) increased risk of ovarian cancer. We also confirmed the positive association between increasing LOYs and ovarian cancer risk in the UK Biobank and the BCFR cohorts. Although interaction on the additive scale was not detected, there were strong positive associations between pathogenic variants in DNA repair genes and ovarian cancer risk. In the UK Biobank, the presence of at least one pathogenic variant in a DNA repair gene was associated with a significant 27% increased risk of epithelial ovarian cancer (EOC) (95% CI 5-55%). Among women at high risk of ovarian cancer due to family history of breast and/or ovarian cancer, there was a strong relationship between BRCA1/2 pathogenic variants and ovarian cancer, regardless of the number of ovulations experienced. The association between LOY and ovarian cancer was found to be consistent and replicable, despite differences in study design, covariates, and measurement. We also detected robust evidence that increasing lifetime ovulations and pathogenic DNA repair variants were associated with ovarian cancer risk. Such variants were exceedingly rare in both cohorts, which limited power to detect interaction in an already rare cancer. Despite such associations, there was no evidence of synergy between LOY and impaired DNA repair capacity, but rather, high LOY and impaired DNA repair capacity may be independent risk factors of ovarian cancer. Each exposure may describe a separate class of women at increased risk of ovarian cancer that should be targeted for future prevention and screening strategies.
130

The Efficacy of Treatment of Symptoms of Polycystic Ovarian Syndrome and Associated Health Risks Using Insulin Sensitizers: A Meta-Analysis

Wong, Isabella J 01 January 2023 (has links) (PDF)
Polycystic Ovarian Syndrome (PCOS) is common among women of reproductive age (ages 15-49), and it can put patients at higher risk for diseases such as type II diabetes or coronary heart disease. While the mechanisms behind PCOS are poorly understood, it is diagnosed using two characteristics: hyperandrogenism and anovulation. Once diagnosed, many patients are also tested for insulin resistance (IR). While IR is thought of as a symptom of PCOS, this study will examine the effects of treatment of IR to manage symptoms of PCOS rather than treatment of hyperandrogenism. This meta-analysis used data from studies previously published by searching for them using key words such as "polycystic ovarian syndrome," "insulin resistance," "hyperandrogenism," and "medication." These data were organized by symptoms studied, and coded. Information extracted was the title, author(s), date of publication, sample size, group characteristics, interventions, and outcomes of each study. This meta-analysis found that the use of insulin sensitizers as treatment for PCOS did not have a greater effect on symptom management than traditional PCOS medications, such as oral contraceptives. These results are useful in the search for a comprehensive and effective treatment of PCOS and may be useful in a clinical setting for treatment guidance purposes.

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