981 resultados para Olsen
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BACKGROUND It is unknown why patients with extensive ulcerative colitis (UC) have a higher risk of colorectal cancer compared with patients with left-sided UC. This study characterizes the inflammatory processes in left-sided UC, pancolitis, and UC-associated dysplasia at the transcriptional level to identify potential biomarkers and transcripts of importance for the carcinogenic behavior of chronic inflammation. METHODS The Affymetrix GeneChip Human Genome U133 Plus 2.0 was applied on colonic biopsies from UC patients with left-sided UC, pancolitis, dysplasia, and controls. Reverse transcription polymerase chain reaction and immunohistochemistry were performed for validating selected transcripts in the initial cohort and in 2 independent cohorts of patients with UC. Microarray data were analyzed by principal component analysis, and reverse transcription polymerase chain reaction and immunohistochemistry data by the Wilcoxon's rank-sum test. RESULTS The principal component analysis results revealed separate clusters for left-sided UC, pancolitis, dysplasia, and controls. Close clustering of dysplastic and pancolitic samples indicated similarities in gene expression. Indeed, 101 and 656 parallel upregulated and downregulated transcripts, respectively, were identified in specimens from dysplasia and pancolitis. Validation of selected transcripts hereof identified insulin receptor alpha (INSRA) and MAP kinase interacting serine/threonine kinase 2 (MKNK2) with an enhanced expression in dysplasia compared with left-sided UC and controls, whereas laminin γ2 (LAMC2) was found with a lower expression in dysplasia compared with the remaining 3 groups. CONCLUSIONS This study demonstrates pancolitis and left-sided UC as distinct inflammatory processes at the transcriptional level, and identifies INSRA, MKNK2, and LAMC2 as potential critical transcripts in the inflammation-driven preneoplastic process of UC.
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The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.
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Introduction Recruiting and retaining volunteers who are prepared to make a long-term commitment is a major problem for Swiss sports clubs. With the inclusion of external counselling for the change and systematisation of volunteer management, sports clubs have a possibility to develop and defuse problems in spite of existing barriers and gaps in knowledge. To what extent is external counselling for personnel problems effective? It is often observed that standardised counselling inputs lead to varying consequences for sports clubs. It can be assumed that external impulses are interpreted and transformed differently into the workings of the club. However, this cannot be solely attributed to the situational or structural conditions of the clubs. It is also important to consider the underlying decision-making processes of a club. According to Luhmann’s organisational sociological considerations (2000), organisations (sports clubs) have to be viewed as social systems consisting of (communicated) decisions. This means that organisations are continually reproduced by decision-making processes. All other (observable) factors such as an organisation’s goals, recruiting strategies, support schemes for volunteers etc., have to be seen as an outcome of the operation of prior organisational decisions. Therefore: How do decision-making processes in sports clubs work in the context of the implementation of external counselling? Theoretical Framework An examination of the actual situation in sports clubs shows that decisions frequently appear to be shaped by inconsistency, unexpected outcomes, and randomness (Amis & Slack, 2003). Therefore, it must be emphasised that these decisions cannot be analysed according to any rational decision-making model. Their specific structural characteristics only permit a limited degree of rationality – bounded rationality. Non-profit organisations in particular are shaped by a specific mode of decisionmaking that Cohen, March, and Olsen (1972) have called the “garbage can model”. As sport clubs can also be conceived as “organised anarchies”, this model seems to offer an appropriate approach to understanding their practices and analysing their decision-making processes. The key concept in the garbage can model is the assumption that decision-making processes in organisations consist of four “streams”: (a) problems, (b) actors, (c) decision-making opportunities, and (d) solutions. Method Before presenting the method of the analysis of the decision-making processes in sports clubs, the external counselling will be described. The basis of the counselling is generated by a sports clubs’ capability to change. Due to the specific structural characteristics and organisational principles, change processes in sports clubs often merge with barriers and restrictions. These need to be considered when developing counselling guidelines for a successful planning and realisation of change processes. Furthermore, important aspects of personnel management in sports clubs and especially volunteer management must be implied in order to elaborate key elements for the counselling to recruit new volunteers (e.g., approach, expectations). A counselling of four system-counselling workshops was conceptualised by considering these specific characteristics. The decision-making processes in the sports clubs were analysed during the counselling and the implementation process. A case study is designed with the appropriate methodological approach for such explorative research. The approach adopted for these single case analyses was oriented toward the research program of behavioural decision-making theory (garbage can model). This posits that in-depth insights into organisational decision-making processes can only be gained through relevant case studies of existing organisational situations (Skille, 2013). Before, during and after the intervention, questionnaires and guided interviews were conducted with the project teams of the twelve par-ticipating football clubs to assess the different components of the “streams” in the context of external counselling. These interviews have been analysed using content analysis following guidelines as for-mulated by Mayring (2010). Results The findings show that decision-making processes in football clubs occur differently in the context of external counselling. Different initial positions and problems are the triggers for these decision-making processes. Furthermore, the implementation of the solutions and the external counselling is highly dependent on the commitment of certain people as central players within the decision-mak-ing process. The importance of these relationships is confirmed by previous findings in regard to decision-making and change processes in sports clubs. The decision-making processes in sports clubs can be theoretically analysed using behavioural decision-making theory and the “garbage can model”. Bounded rationality characterises all “streams” of the decision-making processes. Moreo-ver, the decision-making process of the football clubs can be well illustrated in the framework, and the interplay of the different dimensions illustrates the different decision-making practices within the football clubs. References Amis, J., & Slack, T. (2003). Analysing sports organisations: Theory and practice. In B. Houlihan (Eds.), Sport & Society (pp. 201–217). London, England: Sage. Cohen, M.D., March, J.G., & Olsen, J.P. (1972). A garbage can model of organisational choice. Ad-ministrative Science Quarterly, 17, 1-25. Luhmann, N. (2000). Organisation und Entscheidung. Opladen: Westdeutscher Verlag. Mayring, P. (2010). Qualitative Inhaltsanalyse. Grundlagen und Techniken. Weinheim: Beltz. Skille, E. Å. (2013). Case study research in sport management: A reflection upon the theory of science and an empirical example. In S. Söderman & H. Dolles (Eds.), Handbook of research on sport and business (pp. 161–175). Cheltenham, England: Edward Elgar.
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With the advent of multimodality therapy, the overall five-year survival rate from childhood cancer has improved considerably now exceeding 80% in developed European countries. This growing cohort of survivors, with many years of life ahead of them, has raised the necessity for knowledge concerning the risks of adverse long-term sequelae of the life-saving treatments in order to provide optimal screening and care and to identify and provide adequate interventions. Childhood cancer survivor cohorts in Europe. Considerable advantages exist to study late effects in individuals treated for childhood cancer in a European context, including the complementary advantages of large population-based cancer registries and the unrivalled opportunities to study lifetime risks, together with rich and detailed hospital-based cohorts which fill many of the gaps left by the large-scale population-based studies, such as sparse treatment information. Several large national cohorts have been established within Europe to study late effects in individuals treated for childhood cancer including the Nordic Adult Life after Childhood Cancer in Scandinavia study (ALiCCS), the British Childhood Cancer Survivor Study (BCCSS), the Dutch Childhood Oncology Group (DCOG) LATER study, and the Swiss Childhood Cancer Survivor Study (SCCSS). Furthermore, there are other large cohorts, which may eventually become national in scope including the French Childhood Cancer Survivor Study (FCCSS), the French Childhood Cancer Survivor Study for Leukaemia (LEA), and the Italian Study on off-therapy Childhood Cancer Survivors (OTR). In recent years significant steps have been taken to extend these national studies into a larger pan-European context through the establishment of two large consortia - PanCareSurFup and PanCareLIFE. The purpose of this paper is to present an overview of the current large, national and pan-European studies of late effects after childhood cancer. This overview will highlight the strong cooperation across Europe, in particular the EU-funded collaborative research projects PanCareSurFup and PanCareLIFE. Overall goal. The overall goal of these large cohort studies is to provide every European childhood cancer survivor with better care and better long-term health so that they reach their full potential, and to the degree possible, enjoy the same quality of life and opportunities as their peers.
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Large uncertainties exist concerning the impact of Greenland ice sheet melting on the Atlantic meridional overturning circulation (AMOC) in the future, partly due to different sensitivity of the AMOC to freshwater input in the North Atlantic among climate models. Here we analyse five projections from different coupled ocean–atmosphere models with an additional 0.1 Sv (1 Sv = 10 6 m3/s) of freshwater released around Greenland between 2050 and 2089. We find on average a further weakening of the AMOC at 26°N of 1.1 ± 0.6 Sv representing a 27 ± 14% supplementary weakening in 2080–2089, as compared to the weakening relative to 2006–2015 due to the effect of the external forcing only. This weakening is lower than what has been found with the same ensemble of models in an identical experimen - tal set-up but under recent historical climate conditions. This lower sensitivity in a warmer world is explained by two main factors. First, a tendency of decoupling is detected between the surface and the deep ocean caused by an increased thermal stratification in the North Atlantic under the effect of global warming. This induces a shoaling of ocean deep ventilation through convection hence ventilating only intermediate levels. The second important effect concerns the so-called Canary Current freshwater leakage; a process by which additionally released fresh water in the North Atlantic leaks along the Canary Current and escapes the convection zones towards the subtropical area. This leakage is increasing in a warming climate, which is a consequence of decreasing gyres asymmetry due to changes in Ekman rumping. We suggest that these modifications are related with the northward shift of the jet stream in a warmer world. For these two reasons the AMOC is less susceptible to freshwater perturbations (near the deep water formation sides) in the North Atlantic as compared to the recent historical climate conditions. Finally, we propose a bilinear model that accounts for the two former processes to give a conceptual explanation about the decreasing AMOC sensitivity due to freshwater input. Within the limit of this bilinear model, we find that 62 ± 8% of the reduction in sensitivity is related with the changes in gyre asymmetry and freshwater leakage and 38 ± 8% is due to the reduction in deep ocean ventilation associated with the increased stratification in the North Atlantic.
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The metabolic network of a cell represents the catabolic and anabolic reactions that interconvert small molecules (metabolites) through the activity of enzymes, transporters and non-catalyzed chemical reactions. Our understanding of individual metabolic networks is increasing as we learn more about the enzymes that are active in particular cells under particular conditions and as technologies advance to allow detailed measurements of the cellular metabolome. Metabolic network databases are of increasing importance in allowing us to contextualise data sets emerging from transcriptomic, proteomic and metabolomic experiments. Here we present a dynamic database, TrypanoCyc (http://www.metexplore.fr/trypanocyc/), which describes the generic and condition-specific metabolic network of Trypanosoma brucei, a parasitic protozoan responsible for human and animal African trypanosomiasis. In addition to enabling navigation through the BioCyc-based TrypanoCyc interface, we have also implemented a network-based representation of the information through MetExplore, yielding a novel environment in which to visualise the metabolism of this important parasite.
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Survivors of childhood cancer carry a substantial burden of morbidity and are at increased risk for premature death. Furthermore, clear associations exist between specific therapeutic exposures and the risk for a variety of long-term complications. The entire landscape of health issues encountered for decades after successful completion of treatment is currently being explored in various collaborative research settings. These settings include large population-based or multi-institutional cohorts and single-institution studies. The ascertainment of outcomes has depended on self-reporting, linkage to registries, or clinical assessments. Survivorship research in the cooperative group setting, such as the Children's Oncology Group, has leveraged the clinical trials infrastructure to explore the molecular underpinnings of treatment-related adverse events, and to understand specific complications in the setting of randomized risk-reduction strategies. This review highlights the salient findings from these large collaborative initiatives, emphasizing the need for life-long follow-up of survivors of childhood cancer, and describing the development of several guidelines and efforts toward harmonization. Finally, the review reinforces the need to identify populations at highest risk, facilitating the development of risk prediction models that would allow for targeted interventions across the entire trajectory of survivorship.
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The transition to high school can be challenging for some adolescents, resulting in drops of academic functioning (Barber & Olsen, 2004; Smith, 2006). While changes in academic demands and the disparity between adolescent needs and the environmental characteristics of high school have both been cited as possible contributors to this decrease in academic and personal functioning (Barber & Olsen, 2004), it is possible that teachers may play an even larger role in undermining these students’ functioning, specifically through labeling. Although labeling, and how it can lead to self-fulfilling prophesies, is a concept that has been thoroughly researched and applied to the field of criminology and deviant behavior, it is the goal of this current study to investigate if labeling also occurs in the classroom setting and how such labels ultimately effect the academic potential of high school students.