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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.
301

Cancer of the Urinary Bladder: Gender Differences as Predictors of Tumor Grade

Ikekwere, Joseph, Quinn, Megan, Zheng, Shimin 02 April 2014 (has links)
Group B Streptococcus, or GBS, is a gram positive bacteria commonly found in the gastrointestinal, genital and urinary tract of healthy adults. Between 10% and 30% of all pregnant women are colonized with GBS in the vagina or rectum. While GBS colonized mothers typically show no symptoms or adverse health effects, the bacteria can be passed to their child during labor and delivery. Although significant progress has been made in the identification and treatment of GBS, it remains the leading infectious cause of Page 14 2014 Appalachian Student Research Forum morbidity and mortality among newborns in the United States. The current guidelines recommended by the Center for Disease Control and Prevention (CDC) and endorsed by the American College of Obstetrics and Gynecology (ACOG) is to test pregnant women for GBS colonization between 34-37 weeks of gestation. The current gold standard for identification of GBS colonization is the use of selective enrichment broth (SEB) followed by culture and biochemical testing. Identified concerns with the culture procedure are: 1) the length of time it takes to get the results, 2) the lower sensitivity if the SEB step is left out to improve turn-around-time (TAT) and 3) the limited number of qualified technicians available to perform the complex test. Recently, several semi-automated molecular assays have been developed for identification of GBS which are marketed as having equivalent sensitivity and specificity to SEB followed by culture. The goals of this study were to: 1) validate the sensitivity and specificity of an FDA approved GBS molecular assay (Illumigene, Meridian Bioscience) and 2) evaluate a new testing strategy utilizing SEB followed by the Illumigene GBS assay to see if it offers an improvement in TAT when compared to SEB culture in our in-house microbiology lab and to those sent out to a national reference lab for GBS DNA assay. During the validation process, 20 consecutive samples were submitted to SEB followed by simultaneous in-house culture and Illumigene assay for GBS. The method validation experiments were analyzed using the EP Evaluator version 11 statistical software (Data Innovations). Comparison of TAT was evaluated utilizing a blinded report generated from our Laboratory Information System (Harvest, Orchard Software) for a 2 month period for the GBS tests performed using the SEB followed by Illumigene molecular assay (n=73), in-house SEB followed by culture (n=50) and send-out reference lab GBS DNA assay (n=43) procedures. The TAT (hrs) for each method (Mean±SEM) were determined from the time of collection until result approval. The Illumigene assay had a high sensitivity (100%) and specificity (100%) when compared to SEB followed by culture for identification of GBS. Utilization of the Illumigene assay following SEB significantly (p
302

Les modifications morphologiques de la vessie neurologique humaine : exemples appliqués aux tumeurs de la vessie et à l'hyperactivité détrusorienne / Morphological changes of the human neurogenic bladder : bladder cancer and detrusor overactivity

Phe, Véronique 06 June 2016 (has links)
L’exagération de l’activité contractile spontanée (ACS) et les tumeurs de vessie (TV) sont des modifications morphologiques vésicales observées à moyen et long terme chez les patients ayant une hyperactivité détrusorienne neurogène. Cependant la carcinogénèse vésicale chez les patients neurologiques n’a jamais été étudiée à ce jour et la signification de l’ACS est non élucidée. Nos buts étaient d’étudier la carcinogénèse des vessies neurologiques (en particulier le rôle de l’inflammation chronique) et d’étudier les mécanismes de l’ACS.Nous rapportons que l’expression immunohistochimique de Foxp3 est caractéristique des patients neurologiques ayant une TV agressive de différenciation épidermoïde. Ainsi Foxp3 pourrait être une cible pour le développement d’immunothérapies anti-tumorales. Par une étude en bains d’organes sur des fragments de vessies fraîches issus de patients ayant une hyperactivité détrusorienne neurogène réfractaire, nous observons que l’ACS vésicale in vitro est corrélée à l'âge et la présence de muqueuse vésicale. La modulation pharmacologique de la communication intercellulaire médiée par les connexines 40, 43 et 45 n’inhibe pas l’ACS. La traduction clinique de ces résultats préliminaires est encore difficile. Cependant la compréhension de la signification de l’ACS pourrait identifier de nouvelles voies thérapeutiques pour l’hyperactivité détrusorienne neurogène. Nos résultats ne peuvent pas être argumentés par la littérature encore pauvre à ce sujet. Ce programme de recherche innovant sur les modifications morphologiques à moyen et long terme des vessies neurologiques est poursuivi grâce à une collaboration nationale et à la transversalité des domaines d’expertises des chercheurs impliqués. / Increased spontaneous contractile activity (SCA) and bladder cancer are medium and long-term morphological changes of the bladder observed in patients with neurogenic detrusor overactivity. However, urothelial carcinogenesis in neurological patients has never been studied and the signification of ACS remains unknown. Our objectives were to study the bladder carcinogenesis in neurological patients (in particular the role of chronic inflammation), and the mechanisms of SCA in neurogenic bladders. We report that Foxp3 expression appears to be a characteristic of neurological patients presenting with aggressive bladder cancer and squamous cell differentiation. Thus, targeting Foxp3 may represent an interesting strategy to improve anti-tumor immunotherapy for bladder cancer. By conducting organ bath studies on bladder strips from patients with refractory neurogenic detrusor overactivity, we observe that the in vitro SCA may be modulated by age and the presence of mucosa. The pharmacological modulation of intercellular communication, targeting connexins 40, 43 and 45, cannot inhibit the SCA of neurogenic bladder strips. These results are still difficult to translate into clinical practice. However, understanding the origin of bladder SCA could help identify new therapeutic strategies for detrusor overactivity. Our results are still preliminary and cannot be supported by the literature due to paucity of data. This research program on medium and long-term morphological changes of human neurogenic bladders is pursued through a national collaboration and cross-disciplinary areas of expertise of the researchers involved.
303

Characterizing Sound Production in Nearshore Rockfishes (<em>Sebastes spp.</em>)

Nichols, Bryan 28 July 2005 (has links)
Rockfishes of the genus Sebastes are trophically important in most nearshore environments of the west coast of North America, and support important commercial and recreational fisheries. Though the 72 northeast Pacific species have drumming muscles along their swim bladders, little is known about sound production in the genus. Sounds produced by nearshore rockfish were recorded using fixed hydrophones and underwater video in aquaria, and acoustical dataloggers in the field. Sounds were analyzed from six species: Sebastes nebulosus, S. atrovirens, S.carnatus, S. chrysomelas, S. caurinus, and S.maliger. These six species are closely related, mostly bottom dwelling species with similar drumming musculature. No sounds were recorded from twelve other species in response to diver harassment or agonistic interactions. All the sound production observed was close range, agonistic and relatively quiet (estimated source level 122 dB re 1uPa). Sounds were recorded at all times of the day in the field, presumably from S. nebulosus. While courtship type behavior was observed and video-recorded for only two species, no sounds were produced during courtship. Analysis of the sounds (duration, number of pulses, pulse rate, peak frequency, interpulse interval) from the six species showed considerable overlap between call characteristics, although S. carnatus and S. chrysomelas produced some longer calls with more pulses than the other species. It appears that these agonistic sounds are designed for short-range communication and that they are not species-specific.
304

Experimental Diagnostics and Therapeutics of Invasive Urinary Bladder Cancer

Sherif, Amir January 2003 (has links)
<p>The two purposes of this thesis were to evaluate new diagnostic techniques of lymphnode staging in invasive bladder cancer and to evaluate the results of neoadjuvant chemotherapy in invasive bladder cancer.</p><p>Sentinel node detection was performed in 13 patients in preparation for radical cystectomy. The method showed to be feasible, and the results displayed the occurrence of metastatic nodes outside the traditional area of diagnostic dissection in a majority of patients. Four patients were metastasized, each one with one metastatic node detected with the help of the sentinel node procedure.</p><p>Four randomly selected sentinel nodes from four different unmetastasized patients were compared to the four metastatic sentinel nodes from the first series. After microdissection, p53 genomic structure, immunohistochemical expression and MVD (microvessel density) were assessed in the primary tumors and corresponding sentinel nodes. The results suggested that invasive bladder cancer mainly involved monoclonal proliferation with predominantly homogenous biomarker profile, but there were also signs of clonal evolution.</p><p>The Nordic Cystectomy Trial 2 (NCT2), is a randomized prospective trial investigating the possible benefit of neoadjuvant chemotherapy versus cystectomy only, in 311 eligible patients with urinary bladder cancer T2-T4aNXM0.Evaluation of overall survival did not show any statistically significant benefit in the experimental arm. This probably due to lack of statistical power.</p><p>To increase the statistical power we performed a combined analysis of randomized patients from both the Nordic Cystectomy Trial 1 (NCT1) and NCT2, n = 620. Eligible patients from NCT1 had T1G3, T2-T4a NXM0 urinary bladder cancer. Standard meta-analysis methods were used. The only end-point analysed was overall survival. Neoadjuvant platinum based combination therapy was associated with a 20 % reduction in the relative hazard in probability of death.</p>
305

Cancer Immunotherapy : A Preclinical Study of Urinary Bladder Cancer

Ninalga, Christina January 2006 (has links)
<p>Bacillus Calmette Guérin (BCG), or attenuated Mycobacterium bovis, is the gold standard of immunotherapy in the clinic to treat superficial bladder cancer. However, setbacks remain due to a high recurrence rate, side effects, and BCG-refractory disease. In this thesis, we explored the use of novel immunotherapeutic agents such as CpG oligodeoxynucleotides (CpG ODNs) or synthetic ODNs containing unmethylated CpG dinucleotides. Since unmethylated CpG motifs are predominant in bacterial but not vertebrate DNA, they function as a “danger signal” leading to a potent immune response.</p><p>To be able to test various immunotherapeutic agents, we optimized subcutaneous (s.c.), metastatic, and orthotopic models using the murine bladder-49 (MB49) cancer cell line. In the orthotopic model, we show that poly-L-lysine promotes MB49 attachment to the bladder leading to 100% tumor take. In addition, Clorpactin (sodium oxychlorosene) potently enhances adenoviral transduction in the bladder.</p><p>Utilizing the MB49 model, we compare CpG ODNs with BCG and demonstrate the increased efficacy of CpG ODNs which could cure both s.c. and aggressive orthotopic bladder cancer. In our model, type B ODNs were most optimal and the antitumor response required T cells in order to induce regression and tumor-specific immunity. We also combined CpG ODNs with adenoviral vectors (Ad) expressing the immunostimulatory molecules CD40L, TRANCE, lymphotactin, IL2 or IL15. However, we show that CpG ODNs are effective as a monotherapy and adenoviral vectors did not enhance the effect.</p><p>AdCD40L was also used to genetically modify human dendritic cells (DCs). AdCD40L-transduced DCs not only had a higher and prolonged expression of the Th1 cytokine IL12 compared to TNFα-matured DCs, but CD40L-activated DCs could also resist the suppressive effects of IL10 and TGFβ. Since TNFα is commonly used in clinical DC vaccination protocols and because tumors often secrete immunosuppressive cytokines, these data have important implications for optimizing cancer immunotherapy.</p>
306

Clinical and Epidemiological Studies of Wegener´s Granulomatosis

Knight, Ann January 2007 (has links)
<p>Wegener´s granulomatosis (WG) is an unusual, serious, systemic vasculitis with specific clinical findings. The studies in this thesis aim at broadening our understanding of the aetiology and outcome of WG.</p><p>Patients with WG were identified in the In-patient Register 1975-2001. During this time the incidence increased three-fold, and neither ANCA-related increased awareness, nor diagnostic drift, seem to fully explain this trend, but it is still unclear if a true rise in incidence exists. </p><p>Anti- neutrophil cytoplasmic antibodies (ANCA) have been presented as highly specific for vasculitis. In a series of consecutive cANCA/PR3-ANCA positive patients, we investigated the positive predictive value for ANCA, and the outcome of patients with a positive cANCA/PR3-ANCA but not vasculitis. These patients have a low future risk of developing vasculitis, possibly indicating that ANCA, in this setting, reflects neutrophil activating properties not specific to vasculitis.</p><p>By linkage of the WG-cohort, and randomly selected population controls, to the Multi-generation register, we identified all first-degree relatives and spouses of patients and controls, totally encompassing some 2,000 patients and 70,000 relatives. Familial aggregation of WG was the exception, with absolute risks of < 1 per 1000.However, relative risks in first-grade relatives amounted to 1.56 (95% CI 0.35-6.90) such that a moderate familial aggregation cannot be excluded.</p><p>In the WG-cohort, cancer occurrence and risk was compared to that of the general population. Patients with WG have an overall doubled risk of cancer, with particularly increased risks of bladder-cancer, haematopoietic cancers including lymphomas and squamous skin-cancer. In a case-control study nested within the WG-cohort, treatment with cyclophosphamide was compared among bladder-cancer patients and matched cancer-free controls. Absolute risk of bladder cancer as high as 10% some years after diagnosis were found, and this risk can partly be attributed to cyclophosphamide-treatment, with a dose-response relationship.</p>
307

Experimental Diagnostics and Therapeutics of Invasive Urinary Bladder Cancer

Sherif, Amir January 2003 (has links)
The two purposes of this thesis were to evaluate new diagnostic techniques of lymphnode staging in invasive bladder cancer and to evaluate the results of neoadjuvant chemotherapy in invasive bladder cancer. Sentinel node detection was performed in 13 patients in preparation for radical cystectomy. The method showed to be feasible, and the results displayed the occurrence of metastatic nodes outside the traditional area of diagnostic dissection in a majority of patients. Four patients were metastasized, each one with one metastatic node detected with the help of the sentinel node procedure. Four randomly selected sentinel nodes from four different unmetastasized patients were compared to the four metastatic sentinel nodes from the first series. After microdissection, p53 genomic structure, immunohistochemical expression and MVD (microvessel density) were assessed in the primary tumors and corresponding sentinel nodes. The results suggested that invasive bladder cancer mainly involved monoclonal proliferation with predominantly homogenous biomarker profile, but there were also signs of clonal evolution. The Nordic Cystectomy Trial 2 (NCT2), is a randomized prospective trial investigating the possible benefit of neoadjuvant chemotherapy versus cystectomy only, in 311 eligible patients with urinary bladder cancer T2-T4aNXM0.Evaluation of overall survival did not show any statistically significant benefit in the experimental arm. This probably due to lack of statistical power. To increase the statistical power we performed a combined analysis of randomized patients from both the Nordic Cystectomy Trial 1 (NCT1) and NCT2, n = 620. Eligible patients from NCT1 had T1G3, T2-T4a NXM0 urinary bladder cancer. Standard meta-analysis methods were used. The only end-point analysed was overall survival. Neoadjuvant platinum based combination therapy was associated with a 20 % reduction in the relative hazard in probability of death.
308

Cancer Immunotherapy : A Preclinical Study of Urinary Bladder Cancer

Ninalga, Christina January 2006 (has links)
Bacillus Calmette Guérin (BCG), or attenuated Mycobacterium bovis, is the gold standard of immunotherapy in the clinic to treat superficial bladder cancer. However, setbacks remain due to a high recurrence rate, side effects, and BCG-refractory disease. In this thesis, we explored the use of novel immunotherapeutic agents such as CpG oligodeoxynucleotides (CpG ODNs) or synthetic ODNs containing unmethylated CpG dinucleotides. Since unmethylated CpG motifs are predominant in bacterial but not vertebrate DNA, they function as a “danger signal” leading to a potent immune response. To be able to test various immunotherapeutic agents, we optimized subcutaneous (s.c.), metastatic, and orthotopic models using the murine bladder-49 (MB49) cancer cell line. In the orthotopic model, we show that poly-L-lysine promotes MB49 attachment to the bladder leading to 100% tumor take. In addition, Clorpactin (sodium oxychlorosene) potently enhances adenoviral transduction in the bladder. Utilizing the MB49 model, we compare CpG ODNs with BCG and demonstrate the increased efficacy of CpG ODNs which could cure both s.c. and aggressive orthotopic bladder cancer. In our model, type B ODNs were most optimal and the antitumor response required T cells in order to induce regression and tumor-specific immunity. We also combined CpG ODNs with adenoviral vectors (Ad) expressing the immunostimulatory molecules CD40L, TRANCE, lymphotactin, IL2 or IL15. However, we show that CpG ODNs are effective as a monotherapy and adenoviral vectors did not enhance the effect. AdCD40L was also used to genetically modify human dendritic cells (DCs). AdCD40L-transduced DCs not only had a higher and prolonged expression of the Th1 cytokine IL12 compared to TNFα-matured DCs, but CD40L-activated DCs could also resist the suppressive effects of IL10 and TGFβ. Since TNFα is commonly used in clinical DC vaccination protocols and because tumors often secrete immunosuppressive cytokines, these data have important implications for optimizing cancer immunotherapy.
309

Immunogene Therapy of Bladder Carcinoma : A Preclinical Study

Loskog, Angelica January 2002 (has links)
This thesis comprises studies on murine and human models of bladder carcinoma with the aim to develop novel immunogene therapies. On the basis of the results presented in this thesis, a clinical trial is underway. The potential of activating the immune system to combat cancer has long intrigued immunologists. Research has now been intensified and clinically effective treatments are beginning to materialize. We evaluated the induction of anti-tumor responses by inserting immunomodulating genes into tumor cells with adenovectors. Human biopsies and cell lines were positive for adenovirus attachment receptors, and cell lines were easily transduced. CD40L modified cells efficiently induced maturation of dendritic cell (DC). Phenotypical changes of AdCD40L transduced cells, such as increased apoptotic rate, upregulated MHC-I, Fas and TNFR may further strengthen the anti-tumor response. CD40L modified murine bladder cancer cells activated systemic immunity upon vaccination and in situ injections of AdCD40L inhibited tumor progression. Cytotoxic assays revealed the presence of cytotoxic T cells (CTLs) in vaccinated mice. Many tumors have developed ways to evade the immune system. Bladder carcinoma is associated with immune escape mechanisms like IL10 production. We demonstrated that immunosuppression by IL10 inhibited CTL function and that IL10 suppression may be reverted by AdCD40L therapy. In conclusion, AdCD40L therapy induces systemic immunity and inhibits tumor progression in murine models. The immunological mechanisms involve maturation of nearby DCs and CTL induction. AdCD40L therapy is effective despite immune escape mechanisms, e.g. IL10 secretion. The thesis argues for using AdCD40L immunogene therapy as a treatment of bladder carcinoma.
310

The Quality of Surgical Care for Radical Cystectomy in Ontario from 1992 to 2004

Kulkarni, Girish Satish 20 January 2009 (has links)
This thesis is composed of three studies pertaining to the quality of care for radical cystectomy in Ontario between 1992 and 2004. In the first paper, the associations between provider volume and both operative and overall mortality were assessed. In the second paper, potential factors that could explain the association between volume and outcome were explored. In the final paper, the impact of waiting for cystectomy on survival outcomes was evaluated. Methods: A total of 3296 patients undergoing cystectomy for bladder cancer in Ontario between 1992 and 2004 were identified using the Canadian Institute for Health Information Discharge Abstract Database and the Ontario Cancer Registry. The effects of hospital and surgeon volume on operative mortality and overall survival were assessed using random effects logistic regression and marginal Cox Proportional Hazards modeling, respectively. To elucidate the factors underlying the volume-outcome association, the ability of a number of structure and process of care variables to attenuate the impact of volume was assessed. The effect of waiting for care, from transurethral resection to cystectomy, on overall survival was also assessed using marginal Cox models. Results: Neither hospital nor surgeon volume was significantly associated with operative mortality; however, both were associated with overall mortality. Of the measured structure/process measures, hospital factors caused the greatest attenuation of the volume hazard ratios, albeit to a limited degree. The wait time between the decision for surgery and cystectomy was also significantly associated with overall survival. The impact of delayed care was greatest for patients with lower stage disease. The data suggested a maximum wait time of 40 days for cystectomy. Conclusions: In this thesis, gaps in the quality of care for radical cystectomy in Ontario were identified. Patients treated by low volume hospitals and surgeons or those with long wait times all experienced worse outcomes. Since the underlying measures responsible for provider volume remain elusive, additional work is required to understand what these factors are. Initiatives to decrease wait times, however, are under way in Ontario. Whether these interventions decrease wait times and benefit patients remains to be seen.

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