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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.
171

Synthesis and Characterization of Biologically Active Imidazolium Salts

Hobbs, Mahala S. 28 July 2023 (has links)
No description available.
172

Novel Diagnostic and Prognostic Methods for Cancer and Cancer Associated Thrombosis

Oto Martínez, Ana Julia 02 August 2023 (has links)
Tesis por compendio / [ES] El cáncer constituye la segunda causa de muerte en España. El tromboembolismo venoso (TEV), una complicación del cáncer, conlleva gran gasto del presupuesto sanitario y representa la segunda causa de muerte en estos pacientes. Sin embargo, las herramientas actuales disponibles para la identificación de pacientes oncológicos con elevado riesgo trombótico son limitadas. Adicionalmente, no existen métodos simples, mínimamente invasivos y económicos de diagnóstico de cáncer vesical. Por este motivo, se utilizan técnicas dañinas como la tomografía computarizada la cual implica una elevada dosis de exposición a radiación y procedimientos invasivos como la cistoscopia. Además, un estado hipercoagulable parece tener una relación directa con una mayor carga tumoral y un peor pronóstico. El objetivo principal de la presente Tesis Doctoral es explorar la utilidad clínica de nuevos métodos diagnósticos y pronósticos para el cáncer y sus complicaciones trombóticas. En la primera parte de la Tesis, nos hemos centrado en el papel de miRNAs en orina como biomarcadores de cáncer vesical. Hemos identificado al miR-29c-3p como el miRNA más estable por lo que fue utilizado como normalizador. Hemos ajustado un modelo de regresión logística ordinal para el diagnóstico y estratificación de cáncer vesical utilizando la expresión de miRNAs en orina de pacientes y controles. Este modelo incluyó la expresión de 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p y miR-21-5p. En la segunda parte de la Tesis, nos centramos en el estudio de nuevos biomarcadores para la trombosis asociada a cáncer. Analizamos el potencial predictivo de los miRNAs y de marcadores de activación de neutrófilos en pacientes con cáncer pancreático y pacientes con glioma y meningioma. En cáncer pancreático, obtuvimos un perfil de 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p y miR-103a-3p) capaz de estimar el riesgo de TEV al diagnóstico con dianas incluidas en las rutas pancreatic cancer y complement and coagulation cascades. En el estudio de los marcadores de activación de neutrófilos, obtuvimos un nuevo modelo predictivo de TEV con la calprotectina como variable predictora. Respecto al estudio de trombosis asociada a cáncer en tumores intracraneales, en pacientes con glioma, ajustamos y validamos un modelo predictivo de embolismo pulmonar (EP) postquirúrgico con 6 miRNAs: miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p y miR-140-3p y otro con cfDNA y mieloperoxidasa como predictores. Además, hemos combinado los dos tipos de marcadores y hemos obtenido un modelo con mayor capacidad predictiva que incluye a miR-140-3p y a la mieloperoxidasa como predictores. En pacientes con meningioma, ajustamos y validamos un modelo predictivo de EP postquirúrgico con 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p y miR-23b-3p. En conclusión, proponemos diferentes perfiles de biomarcadores para el diagnóstico de cáncer de vejiga y para la identificación de pacientes oncológicos con elevado riesgo de trombosis. / [CA] El càncer constitueix la segona causa de mort a Espanya. El tromboembolisme venós (TEV), una complicació del càncer, representa la segona causa de mort en aquests pacients i comporta una gran despesa sanitària. No obstant això, les eines disponibles actualment per a la identificació de pacients oncològics amb elevat risc trombòtic són limitades. Actualment, no existeixen mètodes diagnòstics per al càncer de bufeta senzills, mínimament invasius i econòmics. Per aquest motiu, s'utilitzen tècniques nocives com la tomografia computada la qual implica una elevada dosi d'exposició a radiació i procediments invasius com la cistoscòpia. A més, un estat hipercoagulable sembla tindre una relació directa amb una major càrrega tumoral i un pitjor pronòstic. L'objectiu principal de la present Tesi Doctoral fou explorar la utilitat clínica de nous mètodes diagnòstics i pronòstics per al càncer i les seues complicacions trombòtiques. En la primera part de la Tesi, ens hem centrat en el paper dels microRNAs (miRNAs) en orina com biomarcadors de càncer de bufeta. Hem identificat al miR-29c-3p com el miRNA més estable per la qual cosa va ser utilitzat com a normalitzador. Hem ajustat un model de regressió logística ordinal per al diagnòstic i estratificació de càncer de bufeta utilitzant l'expressió de miRNAs en orina de pacients i controls. Aquest model va incloure l'expressió de 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p i miR-21-5p. En la segona part de la Tesi, ens centràrem en l'estudi de nous biomarcadors per a la trombosi associada a càncer. Analitzàrem el potencial predictiu dels miRNAs i de marcadors d'activació de neutròfils en pacients amb càncer pancreàtic i pacients amb glioma i meningioma. En càncer pancreàtic, vàrem obtindre un perfil de 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p i miR-103a-3p) capaç d'estimar el risc de TEV al diagnostic dels pacients els quals tenen dianes incloses en les rutes biològiques pancreatic cancer y complement and coagulation cascades. En el estudi dels marcadors d¿activació de neutròfils, vàrem obtenir un altre model predictiu de TEV amb la calprotectina com a variable predictora. Respecte a l'estudi de trombosi associada a càncer en tumors intracranials, en pacients amb glioma, ajustàrem i validàrem un model predictiu d'embolisme pulmonar (EP) incidental postquirúrgic amb 6 miRNAs (miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p i miR-140-3p) i un altre amb cfDNA i mieloperoxidasa com a predictors. A més, vàrem combinar els dos tipus de marcadors i vàrem obtenir un model amb major capacitat predictiva que inclou al miR-140-3p i la mieloperoxidasa com a predictors. En pacients amb meningioma, ajustàrem i validàrem un model predictiu d¿EP incidental postquirúrgic amb 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p i miR-23b-3p. En conclusió, proposem diferents perfils de biomarcadors per al diagnòstic de càncer de bufeta i per a la identificació de pacients oncològics amb elevat risc de trombosi. / [EN] Cancer is the second leading cause of death in Spain. Collaterally, venous thromboembolism (VTE), as a complication of cancer, consumes a great part of its healthcare budget and, more importantly, it is the second cause of death in these patients. However, limited tools are available to identify high risk patients. Additionally, a simple, minimally invasive and economical diagnostic methods for bladder cancer are also lacking. For that aim, harmful techniques are used like CT scan with high radiation exposure and invasive procedures like cystoscopy. Moreover, a hypercoagulable state seems directly related to a large tumor burden and poor prognosis. The overall aim of this Doctoral Thesis is to explore the clinical utility of novel diagnostic and prognostic methods for cancer and its thrombotic complications. In the first part of this Doctoral Thesis, we focused on the role of urine miRNAs as bladder cancer biomarkers. We identified miR-29c-3p as the most stable miRNA and was therefore used as normalizer. We adjusted an ordinal logistic regression model for the diagnosis and stratification of BC using the urine miRNA expression levels of patients and controls. This model included 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p and miR-21-5p. In the second part of this Doctoral Thesis, we focused on the study of novel biomarkers for cancer-associated thrombosis. We analyzed the predictive potential of miRNAs and neutrophil activation markers of thrombotic events in patients with pancreatic cancer and patients with glioma and meningioma. In pancreatic cancer, we obtained a profile of 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p and miR-103a-3p) able to estimate the risk of potential VTE at diagnosis with targets involved in the pancreatic cancer and complement and coagulation cascades pathways. In the study of the neutrophil activation makers, we obtained a new predictive model of VTE with calprotectin as predictor. Regarding the study of cancer-associated thrombosis in intracranial tumors, in glioma patients, we adjusted and validated a predictive model for post-surgical pulmonary embolism (PE) with 6 miRNAs: miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p and miR-140-3p, and another with cfDNA and myeloperoxidase as predictors. Furthermore, we combined both types of biomarkers and obtained an improved model using myeloperoxidase and miR-140-3p as predictors. In meningioma patients we fitted and validated a predictive model with 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p and miR-23b-3p. In conclusion, we propose several profiles of biomarkers for the diagnosis of bladder cancer and for the identification of oncologic patients at high risk of suffering a thrombotic event. / Oto Martínez, AJ. (2022). Novel Diagnostic and Prognostic Methods for Cancer and Cancer Associated Thrombosis [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181510 / Compendio
173

Utilization of microRNA signatures as a diagnostic tool for canine urothelial carcinoma

Mara Suzann Varvil (16624251) 20 July 2023 (has links)
<p><em>Background:</em> UC is the most common urogenital cancer, comprising up to 2% of all naturally occurring neoplasia in dogs and can be challenging to diagnose. With early diagnosis, the disease can be controlled in most dogs with a good quality of life. MiRNAs are small non-coding RNAs that function by post-transcriptional regulation of gene expression. Their abundant presence and stability in the body make them promising tools for disease diagnosis. </p> <p><em>Hypothesis:</em> A microRNA (miRNA) signature can be used to differentiate canine urothelial carcinoma (UC) from other lower urinary tract diseases.</p> <p><em>Literature review:</em> There is an overlap of miRNA expression changes between normal physiologic processes, non-infectious and non-inflammatory conditions, infectious and/or inflammatory conditions, and neoplasia. Additionally, the mechanism of action of these overlapping miRNAs varies depending on the disease process. There is a lack of standardization of miRNA evaluation and consistency within a single evaluation method. Herein we evaluate three papers on miRNA expression in canine UC and compared the reported expression profile to human UC literature and identified experimentally validated targets of the dysregulated miRNA. </p> <p><em>Methods and results:</em> <strong>(Aim 1)</strong> Using reverse transcriptase quantitative PCR (RT-qPCR), we assessed the effects of sample handling on miRNA expression in formalin-fixed Paraffin-embedded (FFPE) tissue and urine sediment. We showed that the time of tissue fixation in formalin does not alter the detection of miRNA expression, but the inclusion of the muscularis layer altered the miRNA expression profile in bladder tissue. Additionally, miRNAs in urine sediment were proven to be stable despite the storage temperature for up to two weeks. <strong>(Aim 2)</strong> Using Next Generation Sequencing (NGS) with validation of findings via RT-qPCR, we evaluated differential miRNA expression in bladder tissue collected from normal canine urothelium and the invasive type of UC (iUC) to elucidate the dysregulated pathways. We found that twenty-eight miRNAs were differentially expressed (DE). The DE miRNAs were most often associated with gene silencing by miRNA, miRNAs in cancer, and miRNAs involved in DNA damage responses. Proteins involved include HRAS, KRAS, ARAF, RAF1, MAPK1, MAP2K1, MAPK3, FGFR3, EGFR, HBEGF, RASSF1, E2F2, E2F3, ERBB2, SRC, MMP1, and UP3KA. <strong>(Aim 3)</strong> Using RT-qPCR, expression of miR-214, miR-181a, miR-361, and miR-145 were evaluated. We failed to reject the null hypothesis that the relative gene expression in all groups was the same for any miRNA, nor did we find any multivariate summary that could effectively differentiate UC from inflammatory and non-neoplastic transitional cells. </p> <p><em>Conclusions:</em>   The findings within this thesis highlight the need for standardized methods for miRNA evaluation, support the use of stored samples for miRNA expression analysis, and show the importance of isolating the tissue of interest in FFPE. We defined the miRNome of iUC and investigated numerous protein pathways affected by dysregulation of differentially expressed miRNA in urothelial carcinoma. While we failed to reject our null hypothesis that the miRNA signature we evaluated could be utilized as a diagnostic tool for canine urothelial carcinoma, we showed the promise of miRNA as diagnostic tools and highlight several novel pathways that miRNA regulation affects in this disease. </p>
174

Développement et caractérisation de A14-Cy5-ACCUM, un nouvel immunoconjugué fluorescent ciblant un marqueur moléculaire spécifique au cancer de la vessie infiltrant pour la cystoscopie guidée par fluorescence / Development and characterization of A14-Cy5-ACCUM, a new fluorescent immunoconjugate for targeting of muscle invasive bladder cancer during fluorescence-guided cystoscopy

Fafard-Couture, Laurent January 2017 (has links)
Le cancer de la vessie est un cancer fréquent et extrêmement onéreux par patient puisque plusieurs patients subissent des récidives de cancer et ont recours parfois à des chirurgies complexes. Il est donc important de diagnostiquer efficacement ces cancers lors de la prise en charge initiale du patient. En effet, la procédure standard d’imagerie pour la détection du cancer est la cystoscopie de la vessie guidée par lumière blanche, toutefois cette méthode ne permet pas de bien distinguer les cellules qui sont propices à l’invasion musculaire des cellules de cancer de la vessie non infiltrant. Ce mémoire propose d’utiliser un nouvel immunoconjugué fluorescent ciblant la sous-unité alpha du récepteur de l’interleukine 5, un nouveau biomarqueur spécifique aux cellules du cancer de la vessie infiltrant, afin d’effectuer la cystoscopie de la vessie guidée par fluorescence. Pour ce faire, un protocole de conjugaison du fluorochrome cyanine-5 (Cy5) à un anticorps monoclonal a été développé. De plus, un protocole de conjugaison d’un peptide Cell Accumulator (ACCUM) sur cet anticorps fluorescent (A14-Cy5-ACCUM) a été optimisé. Ensuite, la capacité de cet immunoconjugué à marquer les cellules humaines de cancer de la vessie infiltrantes du muscle (MIBC), HT1376, a été testée. Par la suite, un nouveau modèle orthotpique murin de MIBC humain permettant la validation préclinique prochaine de l’A14-Cy5-ACCUM a été développé. Une banque de plasma et sérum sanguin, et d’urine de patients sains et atteints de cancer de la vessie a été compilé. Cette biobanque contient 111 échantillons de plasma sanguin et d’urine qui pourront être utilisé afin de tester l’hypothèse selon laquelle le niveau d’interleukine-5 sanguin pourrait être un facteur pronostique pour la progression du cancer de la vessie. Ce projet jette les bases pour l’évaluation potentielle de la cystoscopie guidée par fluorescence lors de la prise en charge initiale des patients atteints de cancer de la vessie afin d’améliorer la survie sans progression et la survie à long terme des patients atteints de MIBC. / Abstract: Bladder cancer is a frequent and extremely costly cancer when evaluated on a per-patient basis because of its high recurrence rate and patients undergoing complex medical procedures. It is of utmost importance to better identify the aggressiveness of this cancer at initial diagnosis. The standard procedure for bladder cancer detection is still white-light guided cystoscopy, which relies mostly on physicians experience in regard to identifying invasive malignancies. This memoir proposes the use of a new fluorescent immunoconjugate, targeting the alpha subunit of interleukin-5 receptor (IL-5R[apha]), a new biomarker specific to muscle-invasive bladder cancer (MIBC) cells for fluorescence-guided cystoscopy. To do so, a conjugation protocol to fluorescently label a monoclonal antibody with cyanine-5 fluorophores has been developped. Then, a conjugation protocol to attach Cell Accumulator (ACCUM) peptides to this fluorescent immunoconjugate (A14-Cy5-ACCUM) has been optimized. Moreover, the ability of A14-Cy5-ACCUM to stain MIBC cell line HT1376 has been tested. Most importantly, a novel orthotpic rat model of human MIBC for the future preclinical validation of fluorescence-guided cystoscopy in rat bladder has been developped. Finally, a new bladder cancer tissue repository at the CHUS has been established. This repository contains a total of 111 plasma and urine patient samples that will be helpful to evaluate if interleukin-5 blood levels could be used as a prognosis marker for bladder cancer progression. This project laid the basis for the potential evaluation of fluorescence-guided cystoscopy during initial diagnosis of bladder cancer patients to improve their disease-free and long-term survival.
175

The development of CT urography for investigating haematuria

Cowan, Nigel Christopher January 2013 (has links)
This thesis addresses the three principal questions concerning the development of CT urography for investigating haematuria and each question is the subject of a separate chapter. The questions are: What is the reasoning behind using CT urography? What is the optimum diagnostic strategy using CT urography? What are the problems with using CT urography and how may solutions be provided? Haematuria can signify serious disease such as urinary tract stones, renal cell cancer, upper tract urothelial cancer (UTUC) and bladder cancer (BCa). CT urography is defined as contrast enhanced CT examination of kidneys, ureters and bladder. The technique used here includes unenhanced, nephrographic and excretory-phases for optimized diagnosis of stones, renal masses and urothelial cancer respectively. The reasoning behind using excretory-phase CT urography for investigating haematuria is based on results showing its high diagnostic accuracy for UTUC and BCa. Patients with haematuria are classified as low risk or high risk for UTUC and BCa, by a risk score, determined by the presence/absence of risk factors: age > 50 years, visible or nonvisible haematuria, history of smoking and occupational exposure. The optimum diagnostic strategy for patients at high risk for urothelial cancer, uses CT urography as a replacement test for ultrasonography and intravenous urography and as a triage test for flexible and rigid cystoscopy, resulting in earlier diagnosis and potentially improving prognosis. For patients at low risk, ultrasonography, unenhanced and nephrographic-phase CT urography are proposed as initial imaging tests. Problems with using CT urography include false positive results for UTUC, which are eliminated by retrograde ureteropyelography-guided biopsy, an innovative technique, for histopathological confirmation of diagnosis. Recommendations for the NHS and possible future developments are discussed. CT urography, including excretory-phase imaging, is recommended as the initial diagnostic imaging test before cystoscopy for patients with haematuria at high risk for urothelial cancer.
176

Les lipides et les cancers urologiques - approches épidémiologiques. L’importance du temps immortel

Fradet, Vincent 12 1900 (has links)
Objectif: Définir l’effet des lipides et du traitement de la dyslipidémie sur les cancers de la prostate et de la vessie en utilisant différents devis d’étude et en tenant compte de la présence de plusieurs biais, particulièrement le biais du temps immortel. Devis: Le premier volet utilise un devis rétrospectif de type cas témoins. Un questionnaire semi-quantitatif de fréquence de consommation alimentaire validé a été utilisé. Le génotype COX2 de neuf polymorphisme nucléotidique unique (SNP) a été mesuré avec une plateforme Taqman. Des modèles de régression logistique non conditionnelle ont été utilisés pour comparer le risque de diagnostic d’un cancer de la prostate et l’interaction. Le deuxième volet utilise un devis rétrospectif de type cohorte basée sur les données administratives de la Régie de l’assurance-maladie du Québec (RAMQ). Des modèles de régression de Cox ont été employés pour mesurer l’association entre les statines et l’évolution du cancer de la vessie. Le troisième volet, porte un regard méthodologique sur le biais du temps immortel en examinant sa présence dans la littérature oncologique. Son importance est illustrée avec les données de la cohorte du deuxième volet, et les méthodes de correction possibles son appliquées. Résultats: L’étude du premier volet démontre qu’une diète riche en acides gras oméga-3 d’origine marine était fortement associée à un risque diminué de cancer de la prostate agressif (p<0.0001 pour la tendance). Le ratio de cote pour le cancer de la prostate du quartile supérieur d’oméga-3 était de 0.37 (IC 95% = 0.25 à 0.54). L’effet diététique était modifié par le génotype COX-2 SNP rs4648310 (p=0.002 pour l’interaction). En particulier, les hommes avec faible apport en oméga-3 et la variante rs4648310 avait un risque accru de cancer de la prostate (ratio de cote = 5.49, IC 95%=1.80 à 16.7), effet renversé par un apport en oméga-3 plus grand. L’étude du deuxième volet a observé que l’utilisation de statines est associée à une diminution du risque de progression du cancer de la vessie (risque relatif = 0.44, IC 95% = 0.20 à 0.96, p=0.039). Cette association était encore plus forte pour le décès de toute cause (HR = 0.57, 95% CI = 0.43 to 0.76, p=0.0001). L’effet des statines semble être dose-dépendant. L’étude du troisième volet démontre que le biais du temps immortel est fréquent et important dans les études épidémiologiques oncologiques. Il comporte plusieurs aspects dont certains sont mieux prévenus au stade du choix du devis d’étude et différentes méthodes statistiques permettent un contrôle de ce biais. Conclusion: 1) Une diète riche en oméga-3 aurait un effet protecteur pour le cancer de la prostate. 2) L’utilisation de statines aurait un effet protecteur sur la progression du cancer non invasif de la vessie. Les lipides semblent avoir un effet sur les cancers urologiques. / Purpose: To define the effects of dietary lipids and of treatment of dyslipidemia with statins on prostate and bladder cancers, using different epidemiologic study designs and accounting for biases, particularly immortal time bias. Study Design: The first part used a retrospective a case-control study design. Diet was assessed with a semi-quantitative food frequency questionnaire, and nine COX-2 tag single nucleotide polymorphisms (SNPs) were genotyped. We used logistic regression models to estimate odds ratios (ORs), 95% confidence intervals (CIs), and p-values for association and interaction. The second part used a retrospective cohort study design based on administrative databases of Québec, Canada. Cox regression models were used to measure association between statin use and bladder cancer evolution. The third part focuses on the immortal time bias by describing its presence in the oncologic literature. The importance of this bias is illustrated with data from the cohort used in the second part and statistical correction methods are applied. Results: The first part showed that an increasing intake of omega-3 fatty acids of marine origin was strongly associated with a decreased risk of aggressive prostate cancer (trend p<=0.0001). The OR (95% CI) for prostate cancer comparing the highest to the lowest quartile of omega-3 intake was of 0.37 (0.25 – 0.54). The dietary effect was modified by the rs4648310 COX-2 SNP (interaction p=0.02). This reflected the observation that men with low marine omega-3 intake and the variant rs4648310 SNP had an increased risk of disease (OR = 5.49; 95% CI: 1.80-16.7), which was reversed by increasing intake of marine omega-3. The second part showed that statin use was associated with a decreased risk of bladder cancer progression (HR = 0.44, 95% CI = 0.20 to 0.96, p=0.0388). The inverse association was even stronger for risk of mortality from all causes (HR = 0.57, 95% CI = 0.43 to 0.76, p=0.0001). The statin use effect appears dose-dependent. The third part showed that the immortal time bias is frequent and important in many epidemiological studies in oncology. It has many aspects and some of these are better prevented at time of study design selection. Various statistical methods also allowed control of this bias. Conclusion. 1) Dietary omega-3 appears to decrease prostate cancer risk. 2) Statin use appears to decrease risk of bladder cancer progression. Lipids seem to have an effect on urological cancers.
177

Les lipides et les cancers urologiques - approches épidémiologiques. L’importance du temps immortel

Fradet, Vincent 12 1900 (has links)
Objectif: Définir l’effet des lipides et du traitement de la dyslipidémie sur les cancers de la prostate et de la vessie en utilisant différents devis d’étude et en tenant compte de la présence de plusieurs biais, particulièrement le biais du temps immortel. Devis: Le premier volet utilise un devis rétrospectif de type cas témoins. Un questionnaire semi-quantitatif de fréquence de consommation alimentaire validé a été utilisé. Le génotype COX2 de neuf polymorphisme nucléotidique unique (SNP) a été mesuré avec une plateforme Taqman. Des modèles de régression logistique non conditionnelle ont été utilisés pour comparer le risque de diagnostic d’un cancer de la prostate et l’interaction. Le deuxième volet utilise un devis rétrospectif de type cohorte basée sur les données administratives de la Régie de l’assurance-maladie du Québec (RAMQ). Des modèles de régression de Cox ont été employés pour mesurer l’association entre les statines et l’évolution du cancer de la vessie. Le troisième volet, porte un regard méthodologique sur le biais du temps immortel en examinant sa présence dans la littérature oncologique. Son importance est illustrée avec les données de la cohorte du deuxième volet, et les méthodes de correction possibles son appliquées. Résultats: L’étude du premier volet démontre qu’une diète riche en acides gras oméga-3 d’origine marine était fortement associée à un risque diminué de cancer de la prostate agressif (p<0.0001 pour la tendance). Le ratio de cote pour le cancer de la prostate du quartile supérieur d’oméga-3 était de 0.37 (IC 95% = 0.25 à 0.54). L’effet diététique était modifié par le génotype COX-2 SNP rs4648310 (p=0.002 pour l’interaction). En particulier, les hommes avec faible apport en oméga-3 et la variante rs4648310 avait un risque accru de cancer de la prostate (ratio de cote = 5.49, IC 95%=1.80 à 16.7), effet renversé par un apport en oméga-3 plus grand. L’étude du deuxième volet a observé que l’utilisation de statines est associée à une diminution du risque de progression du cancer de la vessie (risque relatif = 0.44, IC 95% = 0.20 à 0.96, p=0.039). Cette association était encore plus forte pour le décès de toute cause (HR = 0.57, 95% CI = 0.43 to 0.76, p=0.0001). L’effet des statines semble être dose-dépendant. L’étude du troisième volet démontre que le biais du temps immortel est fréquent et important dans les études épidémiologiques oncologiques. Il comporte plusieurs aspects dont certains sont mieux prévenus au stade du choix du devis d’étude et différentes méthodes statistiques permettent un contrôle de ce biais. Conclusion: 1) Une diète riche en oméga-3 aurait un effet protecteur pour le cancer de la prostate. 2) L’utilisation de statines aurait un effet protecteur sur la progression du cancer non invasif de la vessie. Les lipides semblent avoir un effet sur les cancers urologiques. / Purpose: To define the effects of dietary lipids and of treatment of dyslipidemia with statins on prostate and bladder cancers, using different epidemiologic study designs and accounting for biases, particularly immortal time bias. Study Design: The first part used a retrospective a case-control study design. Diet was assessed with a semi-quantitative food frequency questionnaire, and nine COX-2 tag single nucleotide polymorphisms (SNPs) were genotyped. We used logistic regression models to estimate odds ratios (ORs), 95% confidence intervals (CIs), and p-values for association and interaction. The second part used a retrospective cohort study design based on administrative databases of Québec, Canada. Cox regression models were used to measure association between statin use and bladder cancer evolution. The third part focuses on the immortal time bias by describing its presence in the oncologic literature. The importance of this bias is illustrated with data from the cohort used in the second part and statistical correction methods are applied. Results: The first part showed that an increasing intake of omega-3 fatty acids of marine origin was strongly associated with a decreased risk of aggressive prostate cancer (trend p<=0.0001). The OR (95% CI) for prostate cancer comparing the highest to the lowest quartile of omega-3 intake was of 0.37 (0.25 – 0.54). The dietary effect was modified by the rs4648310 COX-2 SNP (interaction p=0.02). This reflected the observation that men with low marine omega-3 intake and the variant rs4648310 SNP had an increased risk of disease (OR = 5.49; 95% CI: 1.80-16.7), which was reversed by increasing intake of marine omega-3. The second part showed that statin use was associated with a decreased risk of bladder cancer progression (HR = 0.44, 95% CI = 0.20 to 0.96, p=0.0388). The inverse association was even stronger for risk of mortality from all causes (HR = 0.57, 95% CI = 0.43 to 0.76, p=0.0001). The statin use effect appears dose-dependent. The third part showed that the immortal time bias is frequent and important in many epidemiological studies in oncology. It has many aspects and some of these are better prevented at time of study design selection. Various statistical methods also allowed control of this bias. Conclusion. 1) Dietary omega-3 appears to decrease prostate cancer risk. 2) Statin use appears to decrease risk of bladder cancer progression. Lipids seem to have an effect on urological cancers.
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Analýza volných nukleových kyselin a její potenciální klinické využití. / Analysis of cell-free nucleic acids and its potential clinical application.

Pazourková, Eva January 2019 (has links)
This work presents the results ofour research of cell-free nucleic acids (cfNA). The first part shows changes in methylation patterns of immune response genes promoters that are detectable in plasma during the hemodialysis sessions and also differences in methylation between patients and healthy subjects. Alterations include genes that play their role in the regulation of hematopoiesis and these changes are in close relation with the need of anemia therapy. In the other plasma cfNA study we detected miRNA signatures in patients with acute myeloid leukemia at diagnosis (6 highly abundant miRNAs found) and in remission achieved after standard chemotherapy (trend to n01malization, lower levels ofthese miRNAs). Another part of work presents data from the study of potential non-invasive biomarker of bladder cancer. The amounts of cfDNA in urine are higher in patients than in healthy subjects and there were found 5 down-regulated miRNAs. Simultaneously it was established set of 30 miRNAs that are constantly present in urine supematants independently on sex, age and healthy status of subjects. The last part presents analysis ofcell-free fetal DNA. We analyzed differences between a new quantification method - droplet digital PCR and real-time PCR which is used routinely nowadays. Slightly more precise was...
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PhD Dissertation-Chemistry-Aayush-2023

Aayush Aayush (15354604) 26 April 2023 (has links)
<p> </p> <p>Learning about ‘behavior’ has always been at the heart of my research endeavors. While my undergraduate work in evolution and ecology exposed me to the science behind why a behavior exists, in my graduate work, I intended to explore how to use something’s behavior to widen its applicability. In this thesis, <em>I will present three works that utilize some of the fundamental</em></p> <p><em>behaviors (i.e., properties) of elastin-like polypeptides (ELP) to improve existing protein purification methods or explore their applicability in bladder cancer imaging and immunotherapy. </em></p> <p>Bladder cancer has high recurrence rates (60-70 % annually) that necessitate multiple follow-up therapies making it one of the costliest cancers per patient. In this work, we have attempted to address two leading causes of the recurrence. First is a low sensitivity (62-84 %) and variable specificity (43-95 %) of white light cystoscopy used to diagnose and remove tumors. We aimed to address the heart of this problem, i.e., the non-specific mode of detection using white light. Only the trained eyes can discern abnormal from normal-appearing tissues even then, leaving up to 45% of tumors unresected to colonize and spread. <em>We developed and characterized near infrared dye-peptide-ligand conjugates (NIR-ELP-ligand) that undergo receptor-mediated binding and internalization to human bladder cancer cells in vitro and tissues ex vivo.</em> By using a molecular target-based probe in combination with NIR imaging, we can aid in improving the detection limit via selective binding to the tumor and reduction in background autofluorescence.</p> <p>Bacillus-Calmette Guérin (BCG) instillation in the bladder is the gold-standard</p> <p>immunotherapy used after surgical removal of bladder tumors. This was approved as a response to the inefficiency of surgery alone in improving cancer status. It has succeeded by reducing the recurrence rate to 30-50 %. But it comes with the complications of putting a live mycobacterium</p> <p>in the human body and giving a patient a urinary tract infection right after surgical tumor resection. <em>Thus, we aimed to deliver nucleic acid as immunotherapeutic cargo in a selective manner to elicit robust anti-tumor immune responses while minimizing the side effects due to its carrier.</em> Towards</p> <p>this goal, we have developed a highly modular and adaptable ELP-ligand fusion protein-based nucleic acid delivery carrier targeted toward bladder cancer. Before developing targeted peptide-based cancer imaging and nucleic acid delivery modalities, we addressed the Achilles heel of peptide-based approaches. The peptide and protein industry suffers</p> <p>through complex, time-consuming, inconsistent, and low-yielding purification methods. <em>We have developed a scalable, facile, and reproducible protein purification method that delivers ELP and ELP fusion proteins free of host cell proteins and nucleic acids and has low lipopolysaccharide</em></p> <p><em>content in just 3 h starting from a bacterial pellet. </em>Thus, for a coherent narrative, the thesis is structured as follows:</p> <p>1. Introduction</p> <p>2. ELP as a protein purification tag: Development of a rapid purification method for ELPs and ELP fusion proteins.</p> <p>3. ELP as a cancer imaging agent: Development of NIR-ELP-Ligand imaging probe targeting bladder cancer.</p> <p>4. ELP as a drug delivery agent: Utilizing ELP-ligand fusion protein in the formulation of targeted nucleic acid delivery carrier to bladder cancer.</p>

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