879 resultados para Image Processing in Molecular Biology Research
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The Insulin-like Growth Factor 1 Receptor (IGF-1R) has an essential function in normal cell growth and in cancer progression. However, anti-IGF-1R therapies have mostly been withdrawn from clinical trials owing to a lack of efficacy and predictive biomarkers. IGF-1R activity and signalling in cancer cells is regulated by its C-terminal tail, and in particular, by a motif that encompasses tyrosines 1250 and 1251 flanked by serines 1248 and 1252 (1248- SFYYS-1252). Mutation of Y1250/1251 greatly reduces IGF-1-promoted cell migration, interaction with the scaffolding protein RACK1 in the context Integrin signalling, and IGF- 1R kinase activity. Here we investigated the phosphorylation of the SFYYS motif and characterise the conditions under which this motif may be phosphorylated under. As phosphorylated residues, the SFYYS motif may also serve to recruit interacting proteins to the IGF-1R. To this end we identified a novel IGF-1R interacting partner which requires phosphorylated residues in the SFYYS motif to interact with the IGF-1R. This interaction was found to be IGF-1-dependent, and required the scaffold protein RACK1. The interaction of this binding protein with the IGF-1R likely functions to promote maximal phosphorylation of Shc and ERK in IGF-1-stimulated cell migration, and may be important for IGF-1 signalling in cancer cells. Lastly, we have investigated possible kinases that may confer resistance or sensitivity to the IGF-1R kinase inhibitor BMS-754807. In this screen we identified ATR as a mediator of resistance and showed that suppression or chemical inhibition of ATR synergised with BMS-754807 to reduce colony formation. This work has contributes to our understanding of IGF-1R kinase regulation and signalling and suggests that administration of anti-IGF-1R drugs with ATR inhibitors may have therapeutic benefit.
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Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
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Advances in molecular biology have resulted in novel therapy for neurofibromatosis 2-related (NF2) tumours, highlighting the need for robust outcome measures. The disease-focused NF2 impact on quality of life (NFTI-QOL) patient questionnaire was assessed as an outcome measure for treatment in a multi-centre study. NFTI-QOL was related to clinician-rated severity (ClinSev) and genetic severity (GenSev) over repeated visits. Data were evaluated for 288 NF2 patients (n = 464 visits) attending the English national NF2 clinics from 2010 to 2012. The male-to-female ratio was equal and the mean age was 42.2 (SD 17.8) years. The analysis included NFTI-QOL eight-item score, ClinSev graded as mild, moderate, or severe, and GenSev as a rank order of the number of NF2 mutations (graded as mild, moderate, severe). The mean (SD) 8.7 (5.4) score for NFTI-QOL for either a first visit or all visits 9.2 (5.4) was similar to the published norm of 9.4 (5.5), with no significant relationships with age or gender. NFTI-QOL internal reliability was good, with a Cronbach’s alpha score of 0.85 and test re-test reliability r = 0.84. NFTI related to ClinSev (r = 0.41, p < 0.001; r = 0.46 for all visits), but weakly to GenSev (r = 0.16, p < 0.05; r = 0.15 for all visits). ClinSev related to GenSev (r = 0.41, p < 0.001; r = 0.42 for all visits). NFTI-QOL showed a good reliability and ability to detect significant longitudinal changes in the QOL of individuals. The moderate relationships of NFTI-QOL with clinician- and genetic-rated severity suggest that NFTI-QOL taps into NF2 patient experiences that are not encompassed by ClinSev rating or genotype.
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The choice of model used to study human respiratory syncytial virus (RSV) infection is extremely important. RSV is a human pathogen that is exquisitely adapted to infection of human hosts. Rodent models, such as mice and cotton rats, are semi-permissive to RSV infection and do not faithfully reproduce hallmarks of RSV disease in humans. Furthermore, immortalized airway-derived cell lines, such as HEp-2, BEAS-2B, and A549 cells, are poorly representative of the complexity of the respiratory epithelium. The development of a well-differentiated primary pediatric airway epithelial cell models (WD-PAECs) allows us to simulate several hallmarks of RSV infection of infant airways. They therefore represent important additions to RSV pathogenesis modeling in human-relevant tissues. The following protocols describe how to culture and differentiate both bronchial and nasal primary pediatric airway epithelial cells and how to use these cultures to study RSV cytopathogenesis.
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Histone deacetylases (HDACs) have a central role in the regulation of gene expression, which undergoes alternative splicing during embryonic stem cell (ES) cell differentiation. Alternative splicing gives rise to vast diversity over gene information, arousing public concerns in the last decade. In this chapter, we describe a strategy to detect HDAC7 alternative splicing and analyze its function on ES cell differentiation.
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Immunoglobulin production by myeloma plasma cells depends on the unfolded protein response for protein production and folding. Recent studies have highlighted the importance of IRE1alpha and X box binding protein 1 (XBP1), key members of this pathway, in normal B-plasma cell development. We have determined the gene expression levels of IRE1alpha, XBP1, XBP1UNSPLICED (XBP1u), and XBP1SPLICED (XBP1s) in a series of patients with myeloma and correlated findings with clinical outcome. We show that IRE1alpha and XBP1 are highly expressed and that patients with low XBP1s/u ratios have a significantly better overall survival. XBP1s is an independent prognostic marker and can be used with beta2 microglobulin and t(4;14) to identify a group of patients with a poor outcome. Furthermore, we show the beneficial therapeutic effects of thalidomide in patients with low XBP1s/u ratios. This study highlights the importance of XBP1 in myeloma and its significance as an independent prognostic marker and as a predictor of thalidomide response.
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Lung cancer diagnostics have progressed greatly in the previous decade. Development of molecular testing to identify an increasing number of potentially clinically actionable genetic variants, using smaller samples obtained via minimally invasive techniques, is a huge challenge. Tumour heterogeneity and cancer evolution in response to therapy means that repeat biopsies or circulating biomarkers are likely to be increasingly useful to adapt treatment as resistance develops. We highlight some of the current challenges faced in clinical practice for molecular testing of EGFR, ALK, and new biomarkers such as PDL1. Implementation of next generation sequencing platforms for molecular diagnostics in non-small-cell lung cancer is increasingly common, allowing testing of multiple genetic variants from a single sample. The use of next generation sequencing to recruit for molecularly stratified clinical trials is discussed in the context of the UK Stratified Medicine Programme and The UK National Lung Matrix Trial.
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Photometry of moving sources typically suffers from a reduced signal-to-noise ratio (S/N) or flux measurements biased to incorrect low values through the use of circular apertures. To address this issue, we present the software package, TRIPPy: TRailed Image Photometry in Python. TRIPPy introduces the pill aperture, which is the natural extension of the circular aperture appropriate for linearly trailed sources. The pill shape is a rectangle with two semicircular end-caps and is described by three parameters, the trail length and angle, and the radius. The TRIPPy software package also includes a new technique to generate accurate model point-spread functions (PSFs) and trailed PSFs (TSFs) from stationary background sources in sidereally tracked images. The TSF is merely the convolution of the model PSF, which consists of a moffat profile, and super-sampled lookup table. From the TSF, accurate pill aperture corrections can be estimated as a function of pill radius with an accuracy of 10 mmag for highly trailed sources. Analogous to the use of small circular apertures and associated aperture corrections, small radius pill apertures can be used to preserve S/Ns of low flux sources, with appropriate aperture correction applied to provide an accurate, unbiased flux measurement at all S/Ns.
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This article examines the main assumptions and theoretical underpinnings of case study method in legal studies. It considers the importance of research design, including the crucial roles of the academic literature review, the research question and the use of rival theories to develop hypotheses and the practice of identifying the observable implications of those hypotheses. It considers the selection of data sources and modes of analysis to allow for valid analytical inferences to be drawn in respect of them. In doing so it considers, in brief, the importance of case study selection and variations such as single or multi case approaches. Finally it provides thoughts about the strengths and weaknesses associated with undertaking socio-legal and comparative legal research via a case study method, addressing frequent stumbling blocks encountered by legal researchers, as well as ways to militate them. It is written with those new to the method in mind.
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In this paper, we suggest that portrayal of research is often undervalued and seen as ‘unwork’ (Galloway, 2012). Portrayal is often seen as an issue that is relatively straight forward by qualitative researchers, and invariably refers to putting the findings of the study together with excerpts from participants and usually, but not always, some interpretation. It tends to be seen as the means by which the researcher has chosen to position people and their perspectives, and it is imbued with a sense of not only positioning but also a contextual painting of a person in a particular way. Yet there are an array of issues and challenges about what portrayal can or might mean in digital spaces. In this paper we argue that researching education in a digital age provides greater or different opportunities to represent and portray data differently and suggest that these ways are underutilised. For example, for many researchers legitimacy comes through the use of participants’ voices in the form of quotations. However, we argue that this stance towards plausibility and legitimacy is problematic and needs to be reconsidered in terms of understanding differences in types of portrayal, recognizing how researchers position themselves in relation to portrayal, and understanding decision-making in relation to portrayal. We suggest that there need to be new perspectives about portrayal and concept, and ideas are provided that offer a different view. Three key recommendations are made: Portrayal should be reconceptualised as four overlapping concepts: mustering, folding, cartography, and portrayal. Adopting such an approach will enable audiences, researchers and other stakeholders to critique the assumptions that researchers on tour bring to portrayal and encourage reflexivity. Researchers on tour should highlight the temporal, mutable and shifting nature of portrayed research findings, emphasising the need for continued and varied research to inform understanding. There is a significant need for greater insight into the influence of portrayal, as well as the difference between representation and portrayal. Future studies should prioritise this, and ensure that portrayal is considered and critiqued from the outset.
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Background In addition to the core symptoms, attention deficit hyperactivity disorder (ADHD) is associated with poor emotion regulation. There is some evidence that children and young adults with ADHD have lower omega-3 levels and that supplementation with omega-3 can improve both ADHD and affective symptoms. We therefore investigated differences between ADHD and non-ADHD children in omega-3/6 fatty acid plasma levels and the relationship between those indices and emotion-elicited event-related potentials (ERPs). Methods Children/adolescents with (n=31) and without ADHD (n=32) were compared in their plasma omega-3/6 indices and corresponding ERPs during an emotion processing task. Results Children with ADHD had lower mean omega-3/6 and ERP abnormalities in emotion processing, independent of emotional valence relative to control children. ERP abnormalities were significantly associated with lower omega-3 levels in the ADHD group. Conclusions The findings reveal for the first time that lower omega-3 fatty acids are associated with impaired emotion processing in ADHD children.
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This article considers the place of qualitative research in psychoanalysis and child psychotherapy. It discusses why research methodology for many years occupied so small a place in these fields, and examines the cultural and social developments since the 1960s which have changed this situation, giving formal methods of research much greater significance. It reflects on the different pressures to develop formal research methods which arise both from outside the psychoanalytic field, as a condition of its continued professional survival, and from within it, where its main aim is the development of fundamental psychoanalytic knowledge, It suggests that the conduct of mainly quantitative research into treatment outcomes is largely a response to these external pressures, whilst the main benefits to be gained from the development of qualitative research methods, such as Grounded Theory, are in facilitating the knowledge-generating capacities and achievements of child psychotherapists themselves. The paper describes Grounded Theory methods, and explains how they can be valuable in the recognition of hitherto unrecognised meanings and patterns as these are made visible in clinical practice. Finally, it briefly describes five different examples of completed doctoral studies, all of which have added significantly to the knowledge-base of child psychotherapy, and which demonstrate how much can be accomplished using this method of research.
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This report describes my experience of nine months as a trainee of a CRO (Eurotrials, Scientific Consultants), as well as a trainee of a clinical research site (Clinical Academic Center – Braga, Association). This document describes the European framework about clinical research and the Portuguese situation compared to similar countries. The activities developed during this internship are also described. These activities are divided in two phases. The first one occurred in Eurotrials, Scientific Consultants, a CRO specialized in clinical research and scientific advice. The first weeks were dedicated to intensive self-training needed to perform CTA tasks. These tasks included qualification, initiation and monitoring activities related to clinical trials, as well as the development of a quality management system. The second phase took place on 2CA-Braga, a clinical research center located in Hospital of Braga. Clinical studies coordination was the main focus of this second phase of my internship, as well as negotiation of clinical studies agreements. I had also the opportunity to participate in “1as Jornadas de Investigação Clínica e Inovação” (1st Clinical Investigation and Innovation Conference) organized by 2CA-Braga. Globally, this internship was a great opportunity to get knowledge and experience in the implementation and management of clinical trials, in a CRO and clinical research site perspectives. These two perspectives provided an interesting overview about the scientific needs of different players involved in clinical research. To conclude, this internship strengthened the knowledge acquired from my academic background, which make me able to face and overcome new challenges in the clinical research area.