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Life Sciences

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Washington University in St. Louis

2017

Articles 1 - 9 of 9

Full-Text Articles in Engineering

Binding Affinity And Specificity Of Sh2 Domain Interactions In Receptor Tyrosine Kinase Signaling Networks, Tom Ronan Dec 2017

Binding Affinity And Specificity Of Sh2 Domain Interactions In Receptor Tyrosine Kinase Signaling Networks, Tom Ronan

McKelvey School of Engineering Theses & Dissertations

Receptor tyrosine kinase (RTK) signaling mechanisms play a central role in intracellular signaling and control development of multicellular organisms, cell growth, cell migration, and programmed cell death. Dysregulation of these signaling mechanisms results in defects of development and diseases such as cancer. Control of this network relies on the specificity and selectivity of Src Homology 2 (SH2) domain interactions with phosphorylated target peptides. In this work, we review and identify the limitations of current quantitative understanding of SH2 domain interactions, and identify severe limitations in accuracy and availability of SH2 domain interaction data. We propose a framework to address some …

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Characterization Of Structural Dynamics Of The Human Head Using Magnetic Resonance Elastography, Andrew Arun Badachhape Dec 2017

Characterization Of Structural Dynamics Of The Human Head Using Magnetic Resonance Elastography, Andrew Arun Badachhape

McKelvey School of Engineering Theses & Dissertations

In traumatic brain injury (TBI), the skull-brain interface, composed of three meningeal layers: the dura mater, arachnoid mater, and pia mater, along with cerebrospinal fluid (CSF) between the layers, plays a vital role in transmitting motion from the skull to brain tissue. Magnetic resonance elastography (MRE) is a noninvasive imaging modality capable of providing in vivo estimates of tissue motion and material properties. The objective of this work is to augment human and phantom MRE studies to better characterize the mechanical contributions of the skull-brain interface to improve the parameterization and validation of computational models of TBI. Three specific aims …

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Identification Of Prognostic Cancer Biomarkers Through The Application Of Rna-Seq Technologies And Bioinformatics, Nathan Wong Dec 2017

Identification Of Prognostic Cancer Biomarkers Through The Application Of Rna-Seq Technologies And Bioinformatics, Nathan Wong

McKelvey School of Engineering Theses & Dissertations

MicroRNAs (miRNAs) are short single-stranded RNAs that function as the guide sequence of the post-transcriptional regulatory process known as the RNA-induced silencing complex (RISC), which targets mRNA sequences for degradation through complementary binding to the guide miRNA. Changes in miRNA expression have been reported as correlated with numerous biological processes, including embryonic development, cellular differentiation, and disease manifestation. In the latter case, dysregulation has been observed in response to infection by human papillomavirus (HPV), which has also been established as both oncogenic in cervical cancers and oropharyngeal cancers and favorable for overall patient survival after tumor formation. The identification of …

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Extrinsic And Intrinsic Control Of Integrative Processes In Neural Systems, Anirban Nandi Dec 2017

Extrinsic And Intrinsic Control Of Integrative Processes In Neural Systems, Anirban Nandi

McKelvey School of Engineering Theses & Dissertations

At the simplest dynamical level, neurons can be understood as integrators. That is, neurons accumulate excitation from afferent neurons until, eventually, a threshold is reached and they produce a spike. Here, we consider the control of integrative processes in neural circuits in two contexts. First, we consider the problem of extrinsic neurocontrol, or modulating the spiking activity of neural circuits using stimulation, as is desired in a wide range of neural engineering applications. From a control-theoretic standpoint, such a problem presents several interesting nuances, including discontinuity in the dynamics due to the spiking process, and the technological limitations associated with …

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Characterizing Anisotropy In Fibrous Soft Materials By Mr Elastography Of Slow And Fast Shear Waves, John Larson Schmidt Dec 2017

Characterizing Anisotropy In Fibrous Soft Materials By Mr Elastography Of Slow And Fast Shear Waves, John Larson Schmidt

McKelvey School of Engineering Theses & Dissertations

The general objective of this work was to develop experimental methods based on magnetic resonance elastography (MRE) to characterize fibrous soft materials. Mathematical models of tissue biomechanics capable of predicting injury, such as traumatic brain injury (TBI), are of great interest and potential. However, the accuracy of predictions from such models depends on accuracy of the underlying material parameters. This dissertation describes work toward three aims. First, experimental methods were designed to characterize fibrous materials based on a transversely isotropic material model. Second, these methods are applied to characterize the anisotropic properties of white matter brain tissue ex vivo. Third, …

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Mechanobiology Of Epithelial Clusters In Ecms Of Diverse Mechanical Properties, Samila Nasrollahi Aug 2017

Mechanobiology Of Epithelial Clusters In Ecms Of Diverse Mechanical Properties, Samila Nasrollahi

McKelvey School of Engineering Theses & Dissertations

Cell clusters reside in complex extracellular matrices (ECMs) of varying mechanical properties. Epithelial cells sense and translate the mechanical cues presented by the surrounding ECM into biochemical signals through a process called ‘mechanotransduction’, which controls fundamental aspects of disease and development. During the course of metastasis, mechanical changes in the tumor microenvironment can lead to declustering of epithelial cells through a process called epithelial-to-mesenchymal transition (EMT). Throughout different steps of metastasis, escaped epithelial clusters encounter heterogeneous tissues of varying mechanical properties that ultimately influence their behavior in distant locations within the body. This dissertation investigates the mechanobiology of epithelial clusters …

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Robust Odorant Recognition In Biological And Artificial Olfaction, Nalin Katta Aug 2017

Robust Odorant Recognition In Biological And Artificial Olfaction, Nalin Katta

McKelvey School of Engineering Theses & Dissertations

Accurate detection and identification of gases pose a number of challenges for chemical sensory systems. The stimulus space is enormous; volatile compounds vary in size, charge, functional groups, and isomerization among others. Furthermore, variability arises from intrinsic (poisoning of the sensors or degradation due to aging) and extrinsic (environmental: humidity, temperature, flow patterns) sources. Nonetheless, biological olfactory systems have been refined over time to overcome these challenges. The main objective of this work is to understand how the biological olfactory system deals with these challenges, and translate them to artificial olfaction to achieve comparable capabilities. In particular, this thesis focuses …

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The Impact Of The Mitochondrial Metabolism Of Induced Pluripotent Stem Cells Upon Differentiation, Stefanie T. Shahan May 2017

The Impact Of The Mitochondrial Metabolism Of Induced Pluripotent Stem Cells Upon Differentiation, Stefanie T. Shahan

McKelvey School of Engineering Theses & Dissertations

Induced pluripotent stem cells (iPSCs) can be differentiated into any cell type found in the body. The derivation of a stem cell derived β cell (SC-β) capable of responding to glucose by secreting insulin was hugely significant for diabetes research and opened up the possibility of cell replacement therapy to combat this widespread disease (Pagliuca et al. 2014). The optimization of differentiation procedures such as this could improve yield, function, cost, and efficiency of a stem cell-derived product. Current approaches to improve differentiation are primarily focused on signal transduction pathways, while the metabolic state of the cells has received little …

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Vrshape: A Virtual Reality Tool For Shaping Movement Compensation, Matthew Hale Foreman May 2017

Vrshape: A Virtual Reality Tool For Shaping Movement Compensation, Matthew Hale Foreman

Arts & Sciences Electronic Theses and Dissertations

The majority of persons living with chronic stroke experience some form of upper extremity motor impairment that affects their functional movement, performance of meaningful activities, and participation in the flow of daily life. Stroke survivors often compensate for these impairments by adapting their movement patterns to incorporate additional degrees of freedom at new joints and body segments. One of the most common compensatory movements is the recruitment of excessive trunk flexion when reaching with the affected upper extremity. Long-term use of these compensations may lead to suboptimal motor recovery and chronic pain or injury due to overuse. Rehabilitation focuses on …

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