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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.
181

Ovarian Toxicity in Breast Cancer Survivors

McArdle, Orla 22 November 2012 (has links)
The long-term natural history of ovarian reserve after adjuvant chemotherapy for breast cancer has been poorly described. We recruited 52 breast cancer survivors treated with adjuvant chemotherapy before 40 years of age who remained premenopausal after chemotherapy treatment. Twenty (38.5%) were more than five years out from treatment. Ovarian reserve estimates were compared with a control group. Anti-Müllerian hormone (AMH), follicle stimulating hormone and luteinizing hormone demonstrated significant differences consistent with reduced ovarian reserve in breast cancer survivors. Mean AMH was 6.65 pmol/l in survivors compared to 17.43 in controls (p < 0.001). Attained age and age at the time of treatment were correlated with AMH levels in breast cancer survivors. Conclusion: Ovarian reserve is significantly reduced in young breast cancer survivors. Age is the major predictor of AMH level in survivors. A 35 year old breast cancer survivor has an AMH level similar to a 45 year old control.
182

Effects of a non-steroidal aromatase inhibitor on ovarian function in cattle

Yapura, Jimena 15 September 2009
Two studies were designed to characterize the effects of a non-steroidal aromatase inhibitor, letrozole, on ovarian function in cattle. The specific objective was to test the hypothesis that letrozole will arrest dominant follicle growth resulting in emergence of a new follicular wave at a predictable interval post-treatment. In a first experiment, postpubertal beef heifers were assigned randomly to four treatment groups and given phosphate-buffered saline (controls; n=10), or letrozole at a dose of 500 (n=9), 250 (n=10), or 125 (n=10) µg/kg intravenously 4 days after follicular ablation (~2.5 days after wave emergence). In a second study, postpubertal beef heifers were assigned randomly to four treatment groups. One group received no treatment (control; n=17) and the other groups (n=9-10) were given 85 µg/kg of letrozole per day (250 µg/kg total dose), from Days 1 to 3, Days 3 to 5, or Days 5 to 7 (Day 0 = pre-treatment ovulation,) corresponding to the periods before, during and after selection of the dominant follicle, respectively. Follicular dynamics were monitored ultrasonically and blood samples were collected for endocrine assays. Follicle diameter profiles and plasma LH, FSH, and estradiol concentrations were analyzed. Additionally, during the second trial, CL diameter profiles and plasma progesterone concentrations were measured. In both studies, the diameter profile of the dominant follicle was larger in heifers treated with letrozole than in control heifers (P<0.05) and the intervals to new wave emergence and onset of regression of the extant dominant follicle were longer (P<0.05) in heifers treated with letrozole than in controls, regardless of the dose (high, medium, or low; single vs multiple) and the stage of the follicle wave in which treatments were initiated. Furthermore, during the second experiment, the mean CL diameter was larger in letrozole-treated heifers, although there were no differences in plasma progesterone concentrations between treated and control animals. The effects on dominant follicle and CL diameter profiles appeared to be the result of the significantly increased plasma LH concentrations observed in letrozole-treated animals during both treatment approaches (single vs multiple dose). Incomplete and inconsistent inhibition of estradiol production and the lack of a surge on FSH observed in both experiments may be a result of insufficient circulating levels of letrozole during the treatment period. In summary, a single or multiple dose of letrozole did not induce regression of the extant dominant follicle, nor did it directly affect FSH release. Conversely, letrozole extended the lifespan of the dominant follicle, in association with increased endogenous levels of LH, thereby delaying the next FSH surge and subsequent follicular wave emergence. Results suggest that letrozole has potential as a non-steroidal method for controlling ovarian function in cattle, but further studies are warranted to clarify dosage and timing of treatment to predictably affect follicular wave dynamics in cattle.
183

Evaluation of texture features for analysis of ovarian follicular development

Bian, Na 02 December 2005
Ovarian follicles in women are fluid-filled structures in the ovary that contain oocytes (eggs). A dominant follicle is physiologically selected and ovulates during the menstrual cycle. We examined the echotexture in ultrasonographic images of the follicle wall of dominant ovulatory follicles in women during natural menstrual cycles and dominant anovulatory follicles which developed in women using oral contraceptives (OC). Texture features of follicle wall regions of both ovulatory and anovulatory dominant follicles were evaluated over a period of seven days before ovulation (natural cycles) or peak estradiol concentrations (OC cycles). Differences in echotexture between the two classes of follicles were found for two co-occurrence matrix derived texture features and two edge-frequency based texture features. Co-occurrence energy and homogeneity were significantly lower for ovulatory follicles while edge density and edge contrast were higher for ovulatory follicles. In the each feature space, the two classes of follicle were adequately separable.</p><p>This thesis employed several statistical approaches to analyses of texture features, such as plotting method and the Mann-Kendall method. A distinct change of feature trend was detected 3 or 4 days before the day of ovulation for ovulatory follicles in the two co-occurrence matrix derived texture features and two edge-frequency-based texture features. Anovulatory follicles, exhibited the biggest variation of the feature value 3 or 4 days before the day on which dominant follicles developed to maximum size. This discovery is believed to correspond to the ovarian follicles responding to system hormonal changes leading to presumptive ovulation.</p>
184

Evaluation of texture features for analysis of ovarian follicular development

Bian, Na 02 December 2005 (has links)
Ovarian follicles in women are fluid-filled structures in the ovary that contain oocytes (eggs). A dominant follicle is physiologically selected and ovulates during the menstrual cycle. We examined the echotexture in ultrasonographic images of the follicle wall of dominant ovulatory follicles in women during natural menstrual cycles and dominant anovulatory follicles which developed in women using oral contraceptives (OC). Texture features of follicle wall regions of both ovulatory and anovulatory dominant follicles were evaluated over a period of seven days before ovulation (natural cycles) or peak estradiol concentrations (OC cycles). Differences in echotexture between the two classes of follicles were found for two co-occurrence matrix derived texture features and two edge-frequency based texture features. Co-occurrence energy and homogeneity were significantly lower for ovulatory follicles while edge density and edge contrast were higher for ovulatory follicles. In the each feature space, the two classes of follicle were adequately separable.</p><p>This thesis employed several statistical approaches to analyses of texture features, such as plotting method and the Mann-Kendall method. A distinct change of feature trend was detected 3 or 4 days before the day of ovulation for ovulatory follicles in the two co-occurrence matrix derived texture features and two edge-frequency-based texture features. Anovulatory follicles, exhibited the biggest variation of the feature value 3 or 4 days before the day on which dominant follicles developed to maximum size. This discovery is believed to correspond to the ovarian follicles responding to system hormonal changes leading to presumptive ovulation.</p>
185

Effects of a non-steroidal aromatase inhibitor on ovarian function in cattle

Yapura, Jimena 15 September 2009 (has links)
Two studies were designed to characterize the effects of a non-steroidal aromatase inhibitor, letrozole, on ovarian function in cattle. The specific objective was to test the hypothesis that letrozole will arrest dominant follicle growth resulting in emergence of a new follicular wave at a predictable interval post-treatment. In a first experiment, postpubertal beef heifers were assigned randomly to four treatment groups and given phosphate-buffered saline (controls; n=10), or letrozole at a dose of 500 (n=9), 250 (n=10), or 125 (n=10) µg/kg intravenously 4 days after follicular ablation (~2.5 days after wave emergence). In a second study, postpubertal beef heifers were assigned randomly to four treatment groups. One group received no treatment (control; n=17) and the other groups (n=9-10) were given 85 µg/kg of letrozole per day (250 µg/kg total dose), from Days 1 to 3, Days 3 to 5, or Days 5 to 7 (Day 0 = pre-treatment ovulation,) corresponding to the periods before, during and after selection of the dominant follicle, respectively. Follicular dynamics were monitored ultrasonically and blood samples were collected for endocrine assays. Follicle diameter profiles and plasma LH, FSH, and estradiol concentrations were analyzed. Additionally, during the second trial, CL diameter profiles and plasma progesterone concentrations were measured. In both studies, the diameter profile of the dominant follicle was larger in heifers treated with letrozole than in control heifers (P<0.05) and the intervals to new wave emergence and onset of regression of the extant dominant follicle were longer (P<0.05) in heifers treated with letrozole than in controls, regardless of the dose (high, medium, or low; single vs multiple) and the stage of the follicle wave in which treatments were initiated. Furthermore, during the second experiment, the mean CL diameter was larger in letrozole-treated heifers, although there were no differences in plasma progesterone concentrations between treated and control animals. The effects on dominant follicle and CL diameter profiles appeared to be the result of the significantly increased plasma LH concentrations observed in letrozole-treated animals during both treatment approaches (single vs multiple dose). Incomplete and inconsistent inhibition of estradiol production and the lack of a surge on FSH observed in both experiments may be a result of insufficient circulating levels of letrozole during the treatment period. In summary, a single or multiple dose of letrozole did not induce regression of the extant dominant follicle, nor did it directly affect FSH release. Conversely, letrozole extended the lifespan of the dominant follicle, in association with increased endogenous levels of LH, thereby delaying the next FSH surge and subsequent follicular wave emergence. Results suggest that letrozole has potential as a non-steroidal method for controlling ovarian function in cattle, but further studies are warranted to clarify dosage and timing of treatment to predictably affect follicular wave dynamics in cattle.
186

Reproduction of striped bass Morone saxatilis a structural, biochemical, and functional characterization of atresia /

Kennedy, Alanna Marie, January 2002 (has links)
Thesis (M.S.)--North Carolina State University, 2002. / Title from PDF t.p. (viewed on Dec. 15, 2005). Includes vita. Includes bibliographical references.
187

Reduced BRCA1 expression in breast and ovarian tumorigenesis /

Gonzalez, Rachel Marie. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 175-190).
188

Programmable bio-nano-chip immunosensor for multiplexed detection of ovarian cancer biomarkers

Raamanathan, Archana 03 July 2013 (has links)
Ovarian cancer is a high mortality disease where early stage detection may have significant survival benefits. Promising next-generation non-invasive, biomarker-based screening modalities involve longitudinal monitoring of serum biomarkers and multi-marker panel detection. Here, rapid, sensitive, precise and multiplexable diagnostic platforms can facilitate biomarker validation along with early detection and screening, and this work attempts to exploit the programmable bio-nano-chip (p-BNC) immunosensor to address these specific translational needs in ovarian cancer. First, the p-BNC was adapted for Cancer Antigen 125 (CA125) quantitation, the current FDA standard, with prominent implications in novel early detection and screening modalities. Antibody pairs binding to distinct epitopes on CA125 were identified and the p-BNC operating variables (incubation times, flow rates and reagent concentrations) were attuned to deliver optimal analytical performance (inter- and intra-assay precision of 1.2% and 1.9% and Limit-of-Detection (LOD) 1.0 U/mL), competitive with current gold standards, but with a short analysis time of 43 minutes. Further validation of the system with advanced stage patient sera (n=20) demonstrated good correlation with 'gold standard' ELISA (R² = 0.97). Next, the p-BNC was adapted for concomitant analysis of CA125 and Human Epididymis Protein 4 (HE4), a novel multiplexed biomarker panel for early detection and screening. The HE4 immunoassay was developed to perform optimally with the 'rate determining' CA125 assay. Cross-reactivity analysis demonstrated high specificity multiplexing. The dose-response curves for the multiplexed CA125 and HE4 immunoassays were congruous with their singleplex counterparts with respective LODs of 0.51 U/mL and 4.18 pM and a total analysis time of 44 minutes. A small pilot scale clinical study was conducted to discriminate between surgically confirmed patient sera (n=8) and corresponding age-matched healthy controls (n=8) utilizing the multiplexed p-BNC, interpreted with a risk of ovarian malignancy algorithm. Successful discrimination was achieved between the groups with Receiver Operating Characteristic (ROC) curve AUC (Area Under the Curve) values of 1.00, 0.984 and 1.00 respectively for CA125, HE4 and the composite marker combination. Taken together, the analytical and clinical performance, multiplexing capabilities and the short turn-around times on the p-BNC offer methodological advancements over current gold standard techniques, indicating strong promise for ovarian cancer diagnostics. / text
189

Unexpected Ovarian Malignancy Found after Laparoscopic Surgery in Patients with Adnexal Masses : A Single Institutional Experience

OKAMOTO, TOMOMITSU, TANAKA, SHIHO, KIKKAWA, FUMITAKA, MIZUNO, MIKA, MIWA, YOKO, KAJIYAMA, HIROAKI, SAITO, SHIGEKO 02 1900 (has links)
No description available.
190

Physical and functional evidence in support of candidate chromosome 3p tumour suppressor genes implicated in epithelial ovarian cancer

Cody, Neal A. L., 1980- January 2008 (has links)
Epithelial ovarian cancer (EOC) is difficult to detect in early stage disease, resulting in a high mortality rate. The molecular events underlying EOC development remain largely unknown. Chromosome 3 exhibits frequent deletions and rearrangements in EOC by cytogenetic analysis. In addition, loss of heterozygosity (LOH) mapping of matched ovarian tumour and constitutional DNA samples exhibits specific regions of chromosome 3 loss involving distinct regions: 3p25-p26, 3p24 and a region proximal to 3p14. Thus, chromosome 3p loss points to the location of tumour suppressor genes (TSG) implicated in tumourigenesis, based on Knudson's 'two-hit' model and the paradigm of the classical TSG. The dissertation hypothesis states at least one TSG implicated in EOC is located on chromosome 3p. A novel complementation approach based on the transfer of normal chromosome 3 fragments into OV-90, a tumourigenic EOC cell line harbouring LOH of the 3p arm, was used to generate functional evidence for chromosome 3p TSGs. Three hybrids exhibited complete suppression of tumourigenic potential based on the inability to form colonies in soft agarose, spheroids in cell culture, and tumours in nude mice xenograft models. While all hybrids had acquired various chromosome 3 regions, they all shared in common a 3p12-pcen interval, suggesting at least one common gene may have affected the suppression of tumourigenicity in the OV-90-derived hybrids. Twelve known/hypothetical genes mapping to 3p12-pcen region were characterized based on gene expression and mutation analysis following a classical model for TSG inactivation. To establish the relevance to EOC, gene expression of candidates was investigated in primary cultures of normal ovarian surface epithelial cells and both malignant serous and benign serous tumour samples. The gene expression and genetic analysis identified seven TSG candidates, none of which appeared to be mutated or transcriptionally silenced based on classical mechanisms of TSG inactivation in OV-90, thus suppression of tumourigenicity may have resulted from the functional complementation of one more haploinsufficient 3p12-pcen genes. Several genes (GBE1, VGLL3, ZNF654 ) appeared underexpressed in malignant tumours and these findings suggest the intriguing possibility that more than one 3p12-pcen gene was involved in the suppression of tumourigenicity in OV-90, and by extension, EOC.

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