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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.
151

Patofyziologie chronické pankreatitidy a karcinomu pankreatu. / Pathophysiology of chronic pancreatitis and pancreatic cancer.

Mačinga, Peter January 2019 (has links)
Chronic pancreatitis is considered a risk factor for pancreatic cancer. An exact mechanism how chronic inflammation of the pancreas leads to pancreatic cancer is not yet understood; the possibility of a shared genetic predisposition for both diseases is also assumed. A similar association in patients with AIP has not yet been demonstrated. The aim of our work was to expand the knowledge about relationship between chronic pancreatitis and pancreatic cancer. We studied the association of the diseases in two synchronous projects. In the first one, we examined the occurrence of pancreatic cancer in patients with autoimmune pancreatitis. In the second project, we investigated the presence of genetics variants associated with chronic pancreatitis in patients with pancreatic cancer. In the retrospective study of our cohort of patients, we were one of the very first in the world to show occurrence of pancreatic cancer in patients with autoimmune pancreatitis, and as the only one, we have defined the characteristics of such patients. To assess the association of the diseases, we performed a systematic review where we identified all reported cases of coincidence of pancreatic cancer and autoimmune pancreatitis; the incidence of cancer in patients with autoimmune pancreatitis was similar to that of patients...
152

SNAIL2 contributes to tumorigenicity and chemotherapy resistance in pancreatic cancer by regulating IGFBP2 / SNAIL2はIGFBP2の制御によって膵癌の腫瘍形成と化学療法抵抗性に寄与する

Masuo, Kenji 25 July 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第24136号 / 医博第4876号 / 新制||医||1060(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 藤田 恭之, 教授 波多野 悦朗, 教授 伊藤 貴浩 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
153

In situ vaccination using unique TLR9 ligand K3-SPG induces long-lasting systemic immune response and synergizes with systemic and local immunotherapy / 新規TLR9リガンドK3-SPGを用いたin situワクチン療法は長期間持続する全身性免疫応答を誘導し、全身または局所免疫療法と相乗効果を示す

Okada, Hirokazu 25 July 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第24139号 / 医博第4879号 / 新制||医||1060(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 森信 暁雄, 教授 上野 英樹, 教授 金子 新 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
154

Loss of Arid1a and Pten in Pancreatic Ductal Cells Induces Intraductal Tubulopapillary Neoplasm via the YAP/TAZ Pathway / 膵管細胞におけるArid1aおよびPtenの欠失により、YAP/TAZ経路を介して膵管内管状乳頭状腫瘍(ITPN)が発生する

Fukunaga, Yuichi 23 May 2023 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第24791号 / 医博第4983号 / 新制||医||1066(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川口 義弥, 教授 小林 恭, 教授 小濱 和貴 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
155

Identifying a novel ferrocene derivative as a K-Ras inhibitor

Rehl, Kristen Marie 26 May 2023 (has links)
No description available.
156

Développement d’une méthode de quantification de dérivés de type biguanide dans les liquides biologiques et tissus par spectrométrie de masse LC-MS et MALDI-TOF

Faraj, Samy 08 1900 (has links)
Le taux de mortalité dû au cancer est en hausse d’année en année. Le cancer du pancréas est l’un des plus mortels. Avec un taux de survie inférieur à 20% un an suivant le diagnostic, il y a une urgence pour développer de nouvelles molécules pour cibler cette maladie. La metformine, un biguanide utilisé cliniquement en tant qu’agent antidiabétique, s’est avérée à avoir des propriétés anticancéreuses. Les patients souffrant de diabète de type 2 prenant la metformine comme traitement sont moins à risque de développer plusieurs cancers dont celui du pancréas. Cependant, la metformine n’étant pas biodisponible, les doses à administrer seraient trop élevées pour la considérer comme thérapie anticancéreuse. Le groupe de recherche Schmitzer a synthétisé de nouveaux analogues de type biguanide plus lipophiles dans le but d’améliorer leur biodisponibilité. Le phényléthynylbenzyle biguanide (PEBB) est un des analogues présentant des propriétés antiprolifératives environ 800 fois plus puissantes que la metformine contre des cellules du cancer du pancréas. L’hexylbiguanide s’est aussi démarqué par sa spécificité pour les cellules cancéreuses et sa faible toxicité pour les cellules saines. Étant de bons candidats, des études in vivo ont été faites sur des souris en leur administrant le PEBB et l’hexylbiguanide afin d’obtenir des informations sur l’absorption et la distribution des composés. Pour ce faire, une méthode par LC-MS en mode multiple reaction monitoring (MRM) a été développée afin de quantifier différents analogues de biguanides dans le plasma de souris. De plus, une méthode par MALDI-TOF a été développée afin de localiser et quantifier les analogues dans les tissus par imagerie couplée à la spectrométrie de masse (IMS). Les expériences réalisées ont permis de suivre les composés dans le plasma et d’établir une cinétique d’absorption révélant que le PEBB atteint sa concentration plasmatique maximale environ à 1h après l’administration et que le composé est éliminé de la circulation sanguine à 80% au bout de 4h. Dans le cas de l’hexylbiguanide, la concentration plasmatique maximale est atteinte environ 30 minutes après l’administration pour être éliminé à plus de 90% après 4h. De plus, les études d’IMS ont révélé que le PEBB se distribue principalement dans le foie et légèrement dans les tumeurs. Aucune accumulation à long terme dans le foie n’a été observée, ce qui signifie que les risques de dommages hépatiques sont faibles. Les deux méthodes développées sont des méthodes puissantes IV et reproductibles afin de quantifier les différents types de biguanides dans les liquides biologiques ainsi que dans les tissus. / The death rate of cancer is increasing every year. Pancreatic cancer is one of the deadliest. With a survival rate of less than 20% one year post diagnosis, there is an emergency to develop new molecules to target this disease. Metformin, a biguanide clinically used as an antidiabetic agent, has been shown to have anticancer properties as well. Patients with type 2 diabetes taking metformin are less likely to develop several cancers including pancreatic cancer. However, due to the poor bioavailability of metformin, the doses would be too high to consider it as an anticancer treatment. The Schmitzer group has synthesized new biguanide analogues that are more lipophilic and thus more bioavailable. Phenylethynylbenzyl biguanide (PEBB) is one of the analogues with about 800 times more effective antiproliferative properties than metformin against pancreatic cancer cells. Hexylbiguanide also stood out for its specificity for cancer cells and its low toxicity for normal cells. In vivo studies were performed on mice by administering PEBB and hexylbiguanide to study the absorption and distribution of the compounds. For this aim, a LC-MS method was developed using Multiple Reaction Monitoring (MRM) mode to quantify different biguanide analogues in mice plasma. Complementarily, a MALDI-TOF method was developed to localize and quantify the analogues in tissues by imaging coupled to mass spectrometry (IMS). The experiments performed allowed to follow the compounds in plasma to establish absorption kinetics. These experiments revealed that PEBB reaches its maximum plasma concentration at 1h after administration and the compound is eliminated from the bloodstream at 80% after 6h. For hexylbiguanide, the maximum plasma concentration is reached about 30 minutes after administration and more than 90% is eliminated after 4 hours. In addition, IMS studies have shown that PEBB is distributed mainly in the liver and slightly in tumors. No accumulation in the liver was observed, which suggests that the risk of liver damage is low. These two methods are powerful and reproducible methods to quantify the different types of biguanides in biological fluids and tissues.
157

To determine the role of the Platelet activating factor - receptor in FOLFIRINOX therapy-mediated microvesicles particle generation

Awasthi, Krishna 08 May 2023 (has links)
No description available.
158

Survival Analysis of Demographic Factors Associated With 5+ Year Survival of Pancreatic Carcinoma

Anama-Green, Chris, Quinn, Megan A. 31 January 2021 (has links)
Background Although pancreatic cancer incidence is low at 13.1 per 100,000 people, this cancer is difficult to treat and carries a poor 5-year survival rate. Additionally, pancreatic cancer survival rates vary disproportionately based on age and race. The objective of this study was to evaluate the association between 5-year survival of pancreatic cancer and the basic demographic factors age, race, and sex. Methods Data were retrieved from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) 18 database, spanning from 2000-2017, using SEER*Stat. SPSS was used to calculate descriptive statistics for vital status, age, race, and sex. Odds ratios with confidence intervals were calculated using Epi Info. Case data were used to conduct survival analysis by age, race, and sex using OriginPro. Results Out of a total of 118,581 cases, 79.3% were White (n = 106,887), 12.5% were Black (n = 16,866), 7.4% were Asian or Pacific Islander (n = 9,960), 0.6% were American Indian/Alaskan Native (n = 792), and 0.2% were unknown race (n = 321). The odds ratio (OR) of dying before reaching 5+ survival was lowest for the Asian or Pacific Islander group (OR = 0.70, 95% CI: 0.66 - 0.74), followed by the group of Black patients (OR = 1.07, 95% CI: 1.02 - 1.13), the White patients group (OR = 1.12, 95% CI: 1.08 - 1.17), and the American Indian/Alaskan Native group (OR = 1.12, 95% CI: 0.89 - 1.40). The largest age group was 65-69 years old, comprising 14.7% (n = 19,866) of the dataset. Probability of 5+ year survival for pancreatic cancer patients was highest for the age group 15-19 years (n = 74). In general, 5+ year survival probability declined with age. Risk of death before reaching 5+ year pancreatic cancer survival was slightly higher in men (OR = 1.03, 95% CI: 1.00 - 1.07), who comprised 50.9% (n = 68,628) of the dataset. Discussion Findings from this study corroborate differences by age, race, and sex discussed in the literature. Differences in survival rates by race depart from some findings in literature documenting no significant differences in treatment outcome by race. Controlling for age in a future study in both race and sex survival probability analyses may be helpful. Further, stratifying by sex in survival probability analysis by race would be illuminating. In addition to survival analysis, regression modeling would be a useful next step.
159

Cerium Oxide Nanoparticles Sensitize Pancreatic Cancer Cells To Radiation By Promoting Acidic Ph, Ros, And Jnk Dependent Apoptosis

Wason, Melissa 01 January 2013 (has links)
Side effects of radiation therapy (RT) remain the most challenging issue for pancreatic cancer treatment. In this report we determined whether and how cerium oxide nanoparticles (CONPs) sensitize pancreatic cancer cells to RT. CONP pretreatment enhanced radiation-induced reactive oxygen species (ROS) production preferentially in acidic cell-free solutions as well as acidic human pancreatic cancer cells. In acidic environments, CONPs favor the scavenging of superoxide radical over the hydroxyl peroxide resulting in accumulation of the latter whereas in neutral pH CONPs scavenge both. CONP treatment prior to RT markedly potentiated the cancer cell apoptosis both in culture and in tumors and the inhibition of the pancreatic tumor growth without harming the normal tissues or host mice. Mechanistically, CONPs were not able to significantly impact RT-induced DNA damage in cancer cells, thereby ruling out sensitization through increased mitotic catastrophe. However, JNK activation, which is known to be a key driver of RT-induced apoptosis, was significantly upregulated by co-treatment with CONPs and RT in pancreatic cancer cells in vitro and human pancreatic tumors in nude mice in vivo compared to CONPs or RT treatment alone. Further, CONP-driven increase in RT-induced JNK activation was associated with marked increases in Caspase 3/7 activation, indicative of apoptosis. We have shown CONPs increase ROS production in cancer cells; ROS has been shown to drive the oxidation of thioredoxin (TRX) 1 which results in the activation of Apoptosis Signaling iv Kinase (ASK) 1. The dramatic increase in ASK1 activation following the co-treatment of pancreatic cancer cells with CONPs followed by RT in vitro suggests that increased the c-Jun terminal kinase (JNK) activation is the result of increased TRX1 oxidation. The ability of CONPs to sensitize pancreatic cancer cells to RT was mitigated when the TRX1 oxidation was prevented by mutagenesis of a cysteine residue, or the JNK activation was blocked by an inhibitor,. Additionally, angiogenesis in pancreatic tumors treated with CONPs and RT was significantly reduced compared to other treatment options. Taken together, these data demonstrate an important role and mechanisms for CONPs in specifically killing cancer cells and provide novel insight into the utilization of CONPs as a radiosensitizer and therapeutic agent for pancreatic cancer.
160

Investigation and characterization of functional nucleic acids in whole human serum for the detection of biomarkers towards diagnostic application / Investigation and characterization of DNAzymes in whole human serum for the detection of biologic targets towards biosensor application

Cozma, Ioana January 2023 (has links)
Steady advancements in diagnostics over the past century have propelled the world of medicine into the more advanced era of preventative medicine, an era with a resoundingly clear message: early detection can save lives. For patients who suffer from either pancreatic cancer or malignant hyperthermia susceptibility, early or preoperative diagnosis, respectively can save lives and minimize morbidity and mortality, in addition to offering cost-savings to hospitals and healthcare systems. Fortunately, significant progress have been made in the fields of metabolomics and biomarker identification. Given the benefits carried by serum biomarkers as targets of screening and diagnostic tool development, we applied functional nucleic acid technology and in vitro selection directly in whole human serum to search for disease-specific biomarkers and associated detection probes without a priori knowledge of the biomarkers pursued. This endeavour simultaneously serves as a proof-of-concept study to establish whether in vitro selection can be successfully performed in human serum. We specifically focused on the derivation of RNA-cleaving DNAzymes (RCD) through in vitro selection, or SELEX (systemic evolution of ligands through exponential exposure). DNAzymes constructed with a fluorogenic signalling molecule were incubated with human serum with the goal of identification of a functional nucleic acid probe capable of detecting the presence of a disease-specific biomarker. Two independent protocols have been designed and executed for the identification of DNAzyme sequences capable of detecting pancreatic cancer and malignant hyperthermia susceptibility, respectively. The first exploration was performed in serum obtained from cancer patients, with the goal of identifying DNAzymes capable of distinguishing pancreatic cancer from other cancer types. To do so, we employed in vitro selection, Next-Generation Sequencing, and bioinformatic analysis. We successfully demonstrated the feasibility of performing in vitro selection with DNAzymes in human serum, evidenced by distinct round-to-round enrichment of a DNA library towards the identification of DNAzymes capable of detecting pancreatic cancer. Additionally, we isolated two DNAzymes capable of distinguishing pancreatic cancer serum from healthy patient serum in fresh collected serum samples. Based on the positive results gathered in the pancreatic cancer in vitro selection project, we subsequently endeavoured to replicate the demonstrated feasibility of performing in vitro selection in human serum. By selecting malignant hyperthermia as the pathology investigated, we simultaneously sought to diversify the scope of DNAzyme detection by establishing whether successful DNAzyme selection can be achieved in a non-acute disease state. Thus, the second exploration was performed in serum obtained from patients who underwent evaluation for malignant hyperthermia susceptibility using the gold-standard caffeine-halothane contracture test. The goal of this project rested on the identification of DNAzymes capable of distinguishing malignant hyperthermia susceptibility in serum and approximating the performance of the gold standard test. We successfully isolated four DNAzyme candidates which demonstrated clinically relevant thresholds of sensitivity and specificity following thorough sensitivity and specificity analysis. In doing so, we once again demonstrated the ability to perform in vitro selection in human serum. Given the complexity of molecular interactions observed over the course of two in vitro selection protocols in human serum, it became clear that distinguishing meaningful target-mediated interactions from non-specific interactions would require advanced bioinformatic analysis. Consequently, using principles of computational biology, we performed a deep exploration of Next-Generation Sequencing results obtained from sequencing our recovered DNA libraries to extract additional data that would inform on the next required steps required to identify a DNAzyme specific for the pathology pursued. In doing so, we identified a two-step method to evaluate the progress of the in vitro selection protocol undertaken, and offered a systematic approach for choosing candidate sequences to undergo further testing based on promising performance in silico. Using this approach, we successfully identified a DNAzyme sequence capable of acting as a general cancer detection probe, with promising potential for diagnostic application. Ultimately, this thesis serves as a feasibility study of a novel approach to both in vitro selection and biomarker identification technique by combining the latest nanotechnology techniques with clinical data and real patient serum samples, and advanced computational biology tools. Despite the inability to identify a highly sensitive and specific DNAzyme capable of advancing towards biosensor construction, several important strides and lessons have been acknowledged, establishing the feasibility of performing in vitro selection in human serum, and outlining strategies for addressing and anticipating challenges with this technique. The hope is for this work to inspire and inform future efforts to apply functional nucleic acid technology to solve current gaps in both the diagnostic and therapeutic branches of medicine, and with the help of computational biology continue to bridge the gap between basic science and clinical medicine. / Dissertation / Doctor of Philosophy (PhD)

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