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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.
281

Magnetic Resonance Imaging for Prediction and Assessment of Treatment Response in Bevacizumab-Treated Recurrent Glioblastoma

Rahman, Rifaquat M 02 May 2016 (has links)
Glioblastoma is the most common primary brain tumor in adults, and it is associated with a dismal prognosis with a median survival of 15 months. Despite treatment with chemotherapy, radiation therapy and surgery, patients inevitably have disease recurrence. Bevacizumab is a monoclonal humanized antibody that inhibits vascular endothelial growth factor signaling, and it has been shown to be effective in recurrent glioblastoma with respect to prolonging progression-free survival (PFS). The use of bevacizumab and other anti-angiogenic agents in recurrent glioblastoma have created novel challenges in interpreting magnetic resonance imaging (MRI) of patients. Furthermore, since only some patients appear to have a durable benefit from bevacizumab, there is a need for imaging biomarkers that can reliably identify this subgroup of patients. Partly due to the challenges created by anti-angiogenic agents, the Response Assessment in Neuro-Oncology (RANO) was proposed to address some of the limitations with traditional response assessment criteria. In the first part of this project, we attempted to validate the RANO criteria by performing a comparative analysis of the RANO criteria vs. the Macdonald criteria using imaging from the phase II BRAIN trial. As we hypothesized, the RANO criteria yielded a significantly decreased PFS by identifying a subset of patients who had progression of nonenhancing tumor evident on T2-weighted imaging. Additionally, response and progression as defined by the RANO criteria correlated with subsequent overall survival (OS) in landmark analyses. While this supports the implementation of RANO criteria for response assessment in glioma clinical trials, future research will be necessary to further improve response assessment by incorporating advanced techniques such as volumetric anatomic assessment, perfusion-weighted MR (PWI-MR), diffusion-weighted MR (DWI-MR), MR spectroscopy (MRS) and positron emission tomography (PET). Advanced imaging techniques are becoming increasingly recognized for their ability to provide objective, non-invasive assessment of treatment response but also to serve as predictive and prognostic biomarkers allowing for stratification of patient subgroups with better treatment outcome. In the second part of the project, we attempted to perform volumetric analysis of tumor size based on conventional MRI, as well as a histogram analysis of apparent diffusion coefficients (ADC) derived from diffusion-weighted MRI, to evaluate imaging parameters as predictors for PFS and OS in a single institution database of recurrent glioblastoma patients initiated on bevacizumab. Volumetric percentage change and absolute early post-treatment volume (3-6 weeks after initiation) of enhancing tumor can stratify survival for patients with recurrent glioblastoma receiving bevacizumab therapy. ADC histogram analysis using a multi-component curve-fitting technique within both enhancing and nonenhancing components of tumor prior to the initiation of bevacizumab can also be used to stratify OS in recurrent glioblastoma patients. While prospective studies are necessary to validate findings, future studies will increasingly incorporate multiparametric approaches to elucidate biomarkers that combine the value of conventional MRI with advanced techniques such as DWI-MR, PWI-MR, MRS and PET to obtain better predictors for PFS and OS in recurrent glioblastoma.
282

Understanding the impact of silver as an emerging contaminant in the Ibaizabal and Gironde estuaries / Compréhension de l’impact de l’argent comme contaminant émergent dans les estuaires d’Ibaizabal et de la Gironde

Rementeria Ugalde, Ane 16 December 2016 (has links)
Les estuaires ont été soumis à une forte pression humaine qui a entraîné la présence de polluants dans leurs eaux et sédiments, par exemple les métaux traces. Les estuaires du Golfe de Gascogne n’en sont pas une exception et les estuaires d’Ibaizabal et de la Gironde sont bien connus pour avoir des concentrations élevées de métaux. Dans ce contexte, les programmes de surveillance de l’environnement se sont appuyés sur l’utilisation des moules et des huîtres comme espèces sentinelles, car les analyses chimiques et biologiques de leurs tissus permettent d’évaluer l’état général de santé de leur environnement. Dans le but d’acquérir une meilleure compréhension des interactions entre la bioaccumulation et des effets toxiques du cuivre (Cu) et de l’argent (Ag) dans les huîtres Crassostrea gigas, ainsi que l’influence de facteurs environnementaux, le présent travail présente une étude de terrain et trois expériences de laboratoire. Parmi les résultats obtenus, on peut souligner que : (I) même si les huîtres et les moules peuvent indiquer correctement l’état de santé des estuaires du Golfe de Gascogne, une accumulation clairement plus élevée de métaux se produit dans les huîtres que dans les moules, (II) la voie d’exposition (directe ou alimentaire)induit des réponses de différentes intensités dans les huîtres, (iii) la toxicité de l’Ag est renforcée par la présence accrue de Cu dans les huîtres et (IV) la salinité a un faible effet sur la toxicité des métaux dans les huîtres. / Estuaries have been subjected to a high human pressure which has led to the presence of pollutants in their waters and sediments including trace metals. The estuaries in the Bay of Biscay do not constitute an exception of this situation and the Ibaizabal and Gironde Estuaries are both very well known for having high metal concentrations in different compartments. In this context, environmental health monitoring programmes have relied on the use of mussels and oysters as sentinel organisms because chemical and biological analyses of their tissues allow assessing the general health status of their surrounding environment. The present work aims at acquiring a deeper understanding of the interactions between bioaccumulation and the toxic effects of copper (Cu) and silver (Ag) in oysters Crassostrea gigas, as well as the effects that environmental factors may have on them, For this, one field study and three laboratory experiments have been carried out. Among the most relevant results obtained it can be highlighted that: (I) both oysters and mussels are useful to properly indicate the health status of estuaries of the Bay of Biscay, yet higher accumulation of metals occurs in oysters than in mussels, (II) the intake pathway (watercolumn and/or food) induces different response intensities in oysters (III) the toxicity of Ag is enhanced in the presence of Cu in oysters and (IV) salinity has a low effect on the toxicity of both metals in oysters.
283

Biomarqueurs rétiniens de la maladie d'Alzheimer et du vieillissement cérébral / Retinal biomarkers of Alzheimer's disease and the cerebral aging

Mendez Gomez, Juan Luis 15 December 2016 (has links)
L’œil et le système nerveux central (SNC) ont une origine embryologique commune et les structures rétiniennes, facilement observables, pourraient refléter les atteintes cérébrales. L’objectif général de cette thèse était d'analyser les relations entre atteintes rétiniennes et manifestations cliniques (déclin cognitif, démence) et paracliniques (imagerie cérébrale) du vieillissement cérébral. Deux "biomarqueurs" rétiniens ont été analysés : les fibres nerveuses de la rétine (RNFL) et les structures vasculaires. Les données utilisées proviennent de la cohorte populationnelle 3 Cités-Alienor. Nous avons montré que les sujets ayant une épaisseur réduite de la RNFL (mesurée par tomographie par cohérence optique spectral-domain, SD-OCT) présentaient des performances diminuées en mémoire épisodique (principale fonction cognitive affectée dans la maladie d’Alzheimer, MA) après 2 ans de suivi ; sur une période aussi courte, aucune association n'a été trouvée avec le risque de démence. Une épaisseur réduite de la RNFL était aussi associée à des paramètres altérés en IRM au niveau des voies visuelles et des régions du système limbique, régions particulièrement vulnérables dans la MA. Enfin nous avons montré qu'une épaisseur réduite de la couche vasculaire choroïde était associée à un volume d’hypersignaux de la substance blanche plus important. Des processus pathologiques vasculaires et neurodégénératifs sont associés dans le vieillissement cérébral. Ainsi, la rétine pourrait refléter les altérations du SNC dans la MA et le vieillissement cérébral. D'autres recherches doivent encore être menées avant de considérer la rétine comme un biomarqueur potentiel du vieillissement cérébral. / The eye and central nervous system (CNS) have a common embryological origin, and easily observable retinal structures may reflect brain damage. The primary objective of this thesis was to analyze the relationship between retinal disorders and clinical (cognitive decline, dementia) and para-clinical (brain imaging) brain aging manifestations. Two types of retinal "biomarkers" were analyzed: the retinal nerve fiber layer (RNFL) and vascular structures. The data used come from the population-based cohort 3-Cities Alienor. We have shown that subjects with reduced RNFL thickness (measured by spectral-domain optical coherence tomography, SD-OCT) showed a reduced episodic memory score (cognitive function that is principally affected in Alzheimer's disease, AD) after 2 years of follow-up; over this short period of time no association with dementia risk was found. A reduced RNFL thickness was also associated with altered MRI parameters in visual pathways and in limbic system regions, which are particularly vulnerable in AD. Finally we have shown that reduced vascular choroid layer thickness was associated with larger white matter hyperintensities volumes. Vascular and neurodegenerative disease processes are associated with brain aging. Thus, alterations in the CNS by AD and brain aging could be reflected in the retina. Other research is still needed before considering the retina as a potential biomarker of brain aging.
284

Recherche de biomarqueurs pronostiques dans l'insuffisance cardiaque / Research of prognostic biomarkers in heart failure

Lemesle, Gilles 08 April 2015 (has links)
La stratification du risque des patients atteints d'insuffisance cardiaque (IC) systolique chronique est essentielle afin d'identifier ceux qui pourront bénéficier de stratégies invasives telle que la transplantation cardiaque. En dépit des avancées récentes, cette stratification nécessite d'être encore améliorée. En effet, certains patients caractérisés à faible risque vont décéder précocement ; et inversement, d'autres identifiés à haut risque auront une survie prolongée.Objectif - Notre objectif était d'investiguer la place d'une analyse protéomique du plasma dans la stratification du risque des patients IC et de découvrir des biomarqueurs circulants associés à la mortalité cardiovasculaire précoce de ces patients.Méthodes et résultats - Pour ce faire, nous avons d'abord désigné 2 populations : une population test et une de validation. Ces 2 populations étaient issues de la population INsuffisance CArdiaque (INCA) constituée de l'ensemble des patients référés à notre centre pour une évaluation pronostique extensive d'une IC systolique chronique (FEVG <45%) entre novembre 1998 et mai 2010. Pour la phase test (population cas/témoins), nous avons sélectionné 198 patients entre novembre 1998 et décembre 2005: 99 patients décédés de cause cardiovasculaire dans les 3 ans suivant l'inclusion (cas) ont été comparés à 99 survivants à 3 ans appariés sur l'âge, le sexe et la cause de l'IC (témoins). Pour la phase de validation, nous avons évalué une cohorte de 344 patients consécutifs inclus entre janvier 2006 et mai 2010. Les populations ont été parfaitement caractérisées. La mortalité cardiovasculaire était définie comme un décès de cause cardiovasculaire, une transplantation en urgence (critère United Network for Organ Sharing status 1) ou une assistance cardiaque en urgence.Une analyse protéomique utilisant la technique SELDI-TOF-MS a ensuite été réalisée dans la population test sur des échantillons de plasma prélevés à l'inclusion. Les échantillons ont été déplétés des protéines majoritaires et analysés après randomisation en duplicate en utilisant des puces CM10 (échangeur de cations) et H50 (hydrophobie). Au total, 42 pics m/z étaient différentiellement abondants entre les cas et les témoins et ont été utilisés pour développer des scores protéomiques prédicteurs de la mortalité cardiovasculaire à l'aide de 3 méthodes statistiques de régression : machine à vecteur de support, régression des moindres carrés partiels et régression logistique de Lasso. Les scores protéomiques ont ensuite été testés dans la population de validation et étaient significativement plus élevés chez les patients qui vont décéder dans les 3 ans avec les 3 méthodes. Ces scores protéomiques persistaient associés à la mortalité cardiovasculaire après ajustement sur les facteurs confondants. De plus, l'utilisation de ces scores permettait une amélioration significative de la discrimination des patients IC par rapport à une évaluation pronostique classique selon les index suivants : "integrated discrimination improvement" et "net reclassification improvement".L'étape suivante a été de procéder à la purification et à l'identification des protéines correspondant aux pics m/z différentiellement abondants dans les 2 populations (n=13). Actuellement, nous avons pu identifier plusieurs apolipoprotéines : 14511 CM10-BM (ApoA1), 29024 CM10-BM (ApoA1), 3267 H50-BM (ApoC1), 6416 H50-BM (ApoC1), 6616 H50-BM (ApoC1), 6825 H50-BM (ApoC1), 8764 H50-BM (ApoC3), 9421 H50-BM (ApoC3). ceci a conduit à la quantification de ces apolipoprotéines dans la population INCA par une technique de "mass reaction monitoring".Conclusion - Une analyse protéomique des protéines du plasma semble améliorer la stratification du risque de mortalité précoce chez les patients atteints d’une IC chronique.Perspectives - Des investigations complémentaires sont en cours afin de déterminer l'impact des apoplipoprotéines dans la stratification du risque de ces patients. / Risk stratification of patients with systolic chronic heart failure (HF) is critical to better identify those who may benefit the most from invasive therapeutic strategies such as cardiac transplantation. In spite of recent advances, risk stratification of HF patients needs to be further improved. Indeed, there remains variability in the prognosis with some patients who are categorized at low risk but experience early mortality; and conversely, patients categorized as severe but have an unexpectedly prolonged survival. Proteomics has been used to provide prognostic information in various diseases.Aim – Our aim was to investigate the potential value of plasma proteomic profiling for risk stratification in HF and to find new circulating biomarkers that are associated with early cardiovascular mortality of chronic HF patients.Methods and results – For that purpose, we first designed 2 populations: a discovery and a validation population. Both populations issued from the INsuffisance CArdiaque (INCA) cohort, which is constituted of all consecutive patients referred in our institution for extensive prognostic evaluation of systolic chronic HF (LVEF <45%) between November 1998 and May 2010. For the discovery phase (case/control population), we selected 198 patients included between November 1998 and December 2005: 99 patients who died from cardiovascular cause within 3 years after the initial evaluation (cases) were individually matched for age, sex, and HF etiology with 99 patients who were still alive at 3 years (controls). For the validation phase, we evaluated a cohort of 344 consecutive patients included between January 2006 and May 2010. Study populations were carefully phenotyped. Cardiovascular death included cardiovascular-related death, urgent transplantations defined as United Network for Organ Sharing status 1 and urgent assist device implantation. A proteomic profiling using surface enhanced laser desorption ionization - time of flight - mass spectrometry was then performed in the case/control discovery population on plasma samples collected at inclusion. Plasma samples were depleted for major proteins and randomly analyzed in duplicate using CM10 (Weak Cation Exchanger) and H50 (Reverse Phase) proteinchip arrays. Forty two ion m/z peaks were found differentially abundant between cases and controls in the discovery population and were used to develop proteomic scores predicting cardiovascular death using 3 statistical regression methods: support vector machine, sparse partial least square discriminant analysis and lasso logistic regression. The proteomic scores were then tested in the validation population and score levels were significantly higher in patients who subsequently died within 3 years with the 3 methods. Proteomic scores remained significantly associated with cardiovascular mortality after adjustment on confounders. Furthermore, use of the proteomic scores allowed a significant improvement in discrimination of HF patients as determined by integrated discrimination improvement and net reclassification improvement indexes on top of “classic” prognostic evaluation. The next step was the purification and identification of the proteins related to the different m/z peaks (n=13) that were found significantly differentially abundant in both populations. We have currently identified several peaks as apolipoproteins: 14511 CM10-BM (ApoA1), 29024 CM10-BM (ApoA1), 3267 H50-BM (ApoC1), 6416 H50-BM (ApoC1), 6616 H50-BM (ApoC1), 6825 H50-BM (ApoC1), 8764 H50-BM (ApoC3), 9421 H50-BM (ApoC3). This has led to the quantification of these apolipoproteins in the INCA population using mass reaction monitoring technique.Conclusion – Proteomic analysis of plasma proteins may help to improve risk prediction of early mortality in HF patients.Perspectives – Further investigations are ongoing in order to determine the impact of the different apolipoproteins tested in risk stratification of chronic HF patients.
285

The Impact of Environmental Heavy Metal Exposures on Pregnancy and Birth Outcomes

Au, Felicia January 2016 (has links)
Background: There is still a paucity of information on maternal biological mechanisms specific to adverse birth outcomes despite maternal environmental exposure and health status being known to influence neonatal morbidity and mortality. The purpose of this study was to explore maternal biomarkers pertinent to infant development in utero, specifically matrix metalloproteinases (MMPs), and determine their relationships to environmental heavy metals such as arsenic, cadmium, lead, mercury, and manganese as well as their relationships to outcomes such as preterm birth, low birth weight and small for gestational age infant outcomes. Methods: A secondary data analysis on 1533 mother-infant pairs from the Maternal and Infant Research on Environmental Chemicals (MIREC) cohort was conducted to statistically test relationships between metals and biomarkers, as well as biomarkers and outcome. A systematic literature review and meta-analysis was also conducted to identify the interdependencies between maternal blood biomarkers relating to adverse pregnancy outcomes. Results: Multivariate regression models were used to estimate odds ratios (OR) for the association between metal concentrations in quartiles and both high (90%) and low (10%) maternal MMP levels. Significant metal-related effects were observed with different MMP responses. A total of 54 studies (35 for meta-analysis), including 43,702 women and evaluating 50 biomarkers, met the inclusion criteria and all subgroups of biomarkers showed significant associations with birth outcomes with no apparent publication bias. Conclusions: Maternal plasma markers may serve as potentially valuable tools in the investigation of maternal molecular mechanisms, especially select toxicity pathways underlying metal-mediated adverse infant outcomes. Further research is still needed to evaluate biomarkers such as proteomic and genetic profiles in other various maternal biological samples.
286

The Effects of Environmental Enrichment and Impoverishment on an Animal Model of Depression and Anxiety: Brain, Behaviour and Immune Function

Mileva, Guergana January 2016 (has links)
While women are diagnosed with depression at twice the rate of men, pre-clinical research on this topic has relied heavily on the responses of male animals. This thesis examined the behavioural and physiological effects of environmental manipulation in the female Wistar-Kyoto rat, a putative animal model of depression. At postnatal day 52, baseline behavioural measures were collected in 36 Wistar and 36 Wistar-Kyoto female rats using the following tests: the elevated plus maze to assess anxiety, the forced swim test for depression-like behaviour, and sucrose preference test to assess hedonic status. At postnatal day 62, the rats were randomly assigned to one of three environments for 30 days: 1) standard housing - 3 rats in one large cage 2) isolated housing - 1 rat per small cage, or 3) environmental enrichment - 6 animals in a multistory cage filled with novel objects and a running wheel. Following 30 days in their housing condition, the same behavioural measures were again collected. Large differences between strains were found with the Wistar-Kyoto females showing significantly less mobility and activity in both the forced swim test and elevated plus maze. Sucrose preference was significantly higher after enrichment in both strains. Post-environment immune cytokine and corticosterone levels were also assessed in these animals at baseline and after the forced swim test. No difference in corticosterone between strains was found at baseline. However, Wistar-Kyoto females had significantly higher corticosterone levels than their Wistar counterparts after the forced swim test. In contrast, Wistar-Kyoto females showed significantly lower serum levels of the pro-inflammatory cytokine IL-1β than Wistar females. In the hippocampus, astroglial staining intensity was significantly increased in the CA1 of Wistar females after environmental enrichment. Glucocorticoid receptor staining in the CA3 was also increased after environmental enrichment in both the Wistar-Kyoto and Wistar animals. Finally there was a trend towards higher levels of glucocorticoid receptors in the amygdala in Wistar-Kyoto animals who experienced environmental enrichment. Taken together, this thesis provides evidence for the effect of environment, specifically enrichment, on behaviour and physiological systems. These results suggest that incorporating social and physical enrichment as part of clinical intervention may benefit individuals with depression.
287

The Use of Urinary Biomarkers to Assess Exposures to Polycyclic Aromatic Hydrocarbons (PAHs) and Other Organic Mutagens

Keir, Jennifer Leslie Ann January 2017 (has links)
Exposure to combustion emissions poses a threat to human health due to the complex mixture of toxic compounds. Polycyclic aromatic hydrocarbons (PAHs) are one group of compounds found within this mixture, and have known carcinogenic and mutagenic properties. Rates of exposure to PAHs depend on a wide range of variables including, but not limited to, demographic, geographical location, dietary habits, smoking habits, and occupation. Understanding magnitude of exposure to these compounds in various groups is imperative to highlight at-risk populations and provide appropriate exposure reduction recommendations. Here, urinary biomarkers are used as a non-invasive, convenient way to assess an individual’s exposure to combustion emissions. Urinary measurements of metabolites of individual PAHs as well as compounds indicative of a physiological condition resulting from combustion emission exposure are used to infer exposure. Pairing urinary data with information from questionnaires collecting data on possible sources of combustion by-product exposure was used to determine situations of high exposures. This thesis investigated the influence of demographic, lifestyle, and occupational factors on urinary levels of PAH metabolites and/or urinary mutagenicity. More specifically, statistical methods were used to analyze population data compiled for the Canadian Health Measures Survey (CHMS). Smoking, age, and sex were identified as the variables most predictive of urinary PAH metabolite concentrations in Canadians. Together with the other demographic and lifestyle variables examined, 24-50% of the variation in the various PAH metabolites was explained. Furthermore, the results obtained illustrated that utilizing PAH metabolites other than the traditionally used 1-hydroxypyrene may be more suitable for certain exposure scenarios (e.g., fluorene metabolites for tobacco smoke exposure). Occupational exposures to combustion emission were investigated in firefighters as they experience above average risk of cancer, thus paired with their obvious involvement with combustion, are an ideal population to apply the use of urinary biomarkers to assess PAH and combustion exposure. The effect of participating in fire suppression activities (i.e., firefighting) on urinary levels of selected PAH metabolites and organic mutagens was examined. Levels of external PAH exposures were assessed using personal air monitoring and surface wipes of skin. Significant increases in urinary PAH metabolites and mutagenicity were seen after fire suppression events. Empirical relationships between urinary PAH metabolites and duration of fire event and skin concentrations of PAHs suggested that dermal contamination during live fire events is a major route of exposure. Overall, the results from both studies identified factors that may affect an individual’s concentrations of urinary biomarkers of combustion emission exposure. This may be used to identify at-risk populations and/or determine effective exposure reduction techniques to these hazardous compounds.
288

Identification et caractérisation de biomarqueurs associés à la progression tumorale du mélanome malin cutané : implication de TRAP1 et PDIA4 / Identification and characterization of biomarkers associated with tumor progression of cutaneous malignant melanoma : involvement of TRAP1 and PDIA4

Bougnoux, Anne-Claire 15 December 2014 (has links)
Bien que le mélanome malin cutané (MMC) ne représente que 10% des cancers cutanés, il en est la forme la plus agressive et est responsable de 90% des décès dus aux cancers de la peau. Son incidence ne cesse d'augmenter ces dernières années et atteint 10.8 cas pour 100 000 habitants chez les hommes et 11 chez les femmes. La survie médiane des patients atteint de mélanome à un stade avancé est de 6.2 mois et seulement 1 patient sur 4 est encore en vie à 1an. Le diagnostic du mélanome est uniquement histopathologique et seul l'examen de la biopsie permet de le poser définitivement. De la même façon, il n'existe pas de marqueurs pronostiques associés au mélanome malin cutané. Seuls des facteurs histologiques tels que l'épaisseur de la tumeur, le degré d'invasion ou encore l'envahissement ganglionnaire ont été validés par l'American Joint Committee on Cancer et servent de facteurs pronostiques. Cependant, bien qu'ils permettent d'évaluer le risque métastatique, leur valeur pronostique est encore très insuffisante. L'objectif de ma thèse est d'identifier et de caractériser les protéines associées à la progression tumorale du MMC. Grâce à une approche protéomique quantitative de type iTRAQ par nanoLC MS/MS, j'ai pu identifier et caractériser 2242 protéines dans un modèle cellulaire de progression tumorale du mélanome. La surexpression de huit de ces protéines dans les lignées tumorales par rapport à la lignée normale a été validée par western blot. Deux d'entre elles, TRAP1 et PDIA4 ont ensuite été validées en immunohistochimie comme marqueurs associés à la progression tumorale dans le MMC. Dans un second temps, l'implication de ces deux protéines dans les mécanismes de carcinogénèse du mélanome a été étudiée. L'inhibition de TRAP1 et de PDIA4 induit une diminution de la migration et de la viabilité de la lignée cellulaire métastatique de mélanome 1676. Enfin, la sous-expression dePDIA4 induit une inhibition du complexe Cycline D/CDK4 provoquant un blocage des cellules en phase G0/G1. Ce blocage passerait par la voie PERK liées au stress du réticulum endoplasmique. / Although cutaneous malignant melanoma (CMM) represents only 10% of skin cancers, it is the most aggressive form with 90% of deaths from skin cancer. The Incidence rate is increasing in recent years to 10.8 cases and 11 cases per 100000, in men and women respectively. The prognosis of metastatic melanoma is poor, with a median survival of only 6.2 months. Histopathologic examination remains the gold standard for melanoma diagnosis. There are no prognostic markers associated with CMM. Only histological factors such as tumor thickness, level of invasion, or lymph node involvement have been validated by the American Joint Committee on Cancer and are currently used as prognostic factors. However, although these histological factors are used to assess the risk of metastasis development, their prognostic value is still very low. The aim of my PhD work is to identify and characterize biomarkers associated with tumor progression of CMM. Using a quantitative proteomics approach (iTRAQ and nanoLCMS/MS), I was able to identify and characterize 2242 proteins in a cellular model of melanoma tumor progression. The overexpression of eight proteins in tumor cell lines compared to the normal cell line was validated by immunoblotting. Among these proteins, TRAP1 and PDIA4 were then validated by immunohistochemistry as markers associated with tumor progression in the CMM. Secondly, the involvement of these two proteins in the mechanisms of melanoma carcinogenesis has been studied. The inhibition of TRAP1 and PDIA4 induces a decrease in migration and viability of the metastatic melanoma cell line. Finally, PDIA4 under expression induce an inhibition of cyclin D/Cdk4 complex leading to G0/G1 cell-cycle arrest dependant of endoplasmic reticulum stress by the PERK pathway.
289

Avaliação do conteúdo de treinamento e sua relação com biomarcadores imunológicos, dano muscular e desempenho físico em jogadores de futebol júnior / Evaluation of the training content and its relationship with immunological biomarkers, muscle damage and performance in junior soccer players

Pascoal, Eduardo Henrique Frazilli, 1989- 12 December 2013 (has links)
Orientador: João Paulo Borin / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-24T08:39:42Z (GMT). No. of bitstreams: 1 Pascoal_EduardoHenriqueFrazilli_M.pdf: 1004451 bytes, checksum: 4cc7d5117e5a112067866ed33e55c0c2 (MD5) Previous issue date: 2014 / Resumo: No âmbito do futebol o volume e a intensidade do trabalho são determinantes no entendimento da carga de treinamento. Para garantir uma adaptação adequada é imprescindível que a relação entre estímulo e recuperação seja suficiente. Cargas elevadas podem ocasionar decréscimos no desempenho, diminuições na resposta imune, aumentos de infecções de vias aéreas superiores (IVAS) e aumento de indicadores de dano muscular, como a creatina quinase (CK). Neste sentido é fundamental entender a organização do conteúdo de treinamento e sua relação com indicadores imunológicos e de dano muscular. Portanto, o objetivo deste estudo foi verificar a influência do conteúdo de treinamento nas concentrações de CK, leucócitos e subséries, relatos de IVAS e desempenho da potência de atletas de futebol juniores durante 10 semanas correspondentes ao período preparatório para a Copa São Paulo Júnior. Participaram do estudo 14 atletas de futebol pertencentes à categoria Sub-19 (18,40 ± 0,88 anos, 179,52 ± 6,96 cm, 73,70 ± 7,22 kg). As coletas ocorreram em dois momentos: M1, período antecedente ao início da pré-temporada; M2, na 11ª semana, final da pré-temporada. Em ambos os momentos foram realizadas coletas e análises sanguíneas de leucócitos, neutrófilos, monócitos, linfócitos, plaquetas e CK. Semanalmente, os atletas respondiam ao questionário de acometimento por IVAS e todo conteúdo de treinamento era registrado e repassado ao pesquisador. Para verificar a potência de membros inferiores foi utilizado o teste de salto vertical com contramovimento (CMJ). Diariamente foi coletado o valor da percepção subjetiva de esforço de cada jogador bem como os minutos das sessões para cálculos da carga interna. Utilizou-se o teste-t de Student para amostras pareadas para as variáveis imunológicas; o teste de Wilcoxon foi utilizado para amostra não-paramétrica de CK e o índice de significância adotado foi ? ? 0,05. Os principais resultados apontam para predominância dos conteúdos de resistência específica (28 sessões; 2075 min), seguido de força geral e específica (26 sessões; 1480 min). Quanto aos indicadores imunológicos e de dano muscular, verificou-se decréscimos significantes na concentração de linfócitos e aumentos significantes nas plaquetas e na CK. A partir dos resultados, os dados apontam que o conteúdo de treinamento aplicado aos atletas no período preparatório diminuiu a resposta imune, aumentou o dano muscular, além de manter a potência muscular. / Abstract: Within the soccer the training¿s volume and intensity are determinants of the training load. To ensure an adequate adaptation it is imperative that the relationship between stimulus and recovery be sufficcient. Highly loads can lead to performance and immune decreases, increases of upper respiratory tract infections (URTI) and muscle damage indicators like creatina kinase (CK). In this sense is critical to understand the organization of the content training and its relationship with immune function and muscle damage indicators. Therefore, the aims of this study were to verify the influence of training content on the CK concentrations, leucocytes and subsets, URTIs reports and lower limb power performance of junior soccer athletes during a 10-week corresponding to the preparatory period for the Junior São Paulo Soccer Cup. Participated of this study fourteen U19 soccer players (18,40 ± 0,88 years, 179,52 ± 6,96 cm, 73,70 ± 7,22 kg). The collections happened in two moments: M1, the precede preseason period; M2, on the 11th week, end of the preseason period. In both moments were performed collections and blood analyses to evaluate the leucocytes, neutrophils, monocytes, lymphocytes, platelet and CK. Weekly the subjects answer the URTIs questionnaire and all training content was registered and transferred to the researcher. It was performed the countermovement jump (CMJ) test to measure the lower limbs power. Daily it was collected the rate of perceived exertion (RPE) of each player for load calculations. The paired Student t-test was used for the immune variables, as well as the Wilcoxon non-parametric test was used to the CK sample and the significance level selected was ? ? 0,05. The main results show the specific endurance predominance (28 sessions; 2075 min), followed by general and specific strength (26 sessions; 1480 min). Regarding to the immune and muscle damage indicators, we verified significant lymphocytes concentration decreases and significant platelet and CK increases. From the results the data indicate that the content training applied to the athletes on the preseason decreased the immune response, increase de muscle damage and maintain the muscle power. / Mestrado / Biodinamica do Movimento e Esporte / Mestre em Educação Física
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Biotic and abiotic control of microbial community structure and activity in forest soils

Gunina, Anna 01 September 2017 (has links)
No description available.

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