Engineering Commons^™

A Gal-Ms Device To Evaluate Cell Migratory Response To Combined Galvano-Chemotactic Fields, Shawn Mishra, Maribel Vazquez

Publications and Research

Electric fields have been studied extensively in biomedical engineering (BME) for numerous regenerative therapies. Recent studies have begun to examine the biological effects of electric fields in combination with other environmental cues, such as tissue-engineered extracellular matrices (ECM), chemical gradient profiles, and time-dependent temperature gradients. In the nervous system, cell migration driven by electrical fields, or galvanotaxis, has been most recently studied in transcranial direct stimulation (TCDS), spinal cord repair and tumor treating fields (TTF). The cell migratory response to galvano-combinatory fields, such as magnetic fields, chemical gradients, or heat shock, has only recently been explored. In the visual system, …

Decreased Triple Network Connectivity In Patients With Recent Onset Post-Traumatic Stress Disorder After A Single Prolonged Trauma Exposure, Yang Liu, Liang Li, Baojuan Li, Na Feng, Lihong Li, Xi Zhang, Hongbing Lu, Hong Yin

Publications and Research

The triple network model provides a common framework for understanding affective and neurocognitive dysfunctions across multiple disorders, including central executive network (CEN), default mode network (DMN), and salience network (SN). Considering the effect of traumatic experience on post-traumatic stress disorder (PTSD), this study aims to explore the alteration of triple network connectivity in a specific PTSD induced by a single prolonged trauma exposure. With an arterial spin labeling sequence, three networks were first identified using independent component analysis among 10 PTSD patients and 10 healthy survivors, who experienced the same coal mining flood disaster. Then, the triple network connectivity was …

Mutagenesis Of Human Alpha-Galactosidase A For The Treatment Of Fabry Disease, Erin Stokes

Dissertations, Theses, and Capstone Projects

Fabry disease is an X-linked lysosomal storage disorder caused by the deficiency of the enzyme, α-galactosidase A, which results in the accumulation of the lipid substrate. This accumulation results in obstruction of blood flow in patients and early demise at approximately 40-60 years of age. There is currently only one FDA approved treatment (Fabrazyme) classified as an enzyme replacement therapy. However, approximately 88% of patients experience a severe immune response that, rarely, can be fatal and is a huge cost burden at average $250,000 a year per patient. The structure of α-galactosidase A has been previously determined to be a …

The Influence Of The Electrode Dimension On The Detection Sensitivity Of Electric Cell–Substrate Impedance Sensing (Ecis) And Its Mathematical Modeling, Xudong Zhang, William Wang, Anis Nurashikin Nordin, Fang Li, Sunghoon Jang, Ioana Voiculescu

Publications and Research

Detection sensitivity is a crucial criterion in the design and application of ECIS sensors. The influence of sensing electrode dimension on detection sensitivity is investigated in this paper. Eight types of ECIS sensors were fabricated, and their experimental results reveal that smaller-radius working electrodes generate more sensitive impedance shift to cell density change. Also, the smaller radius of working electrodes yield higher impedance values, which improves signal-to-noise ratio. In a range from 1.0 mm to 3.5 mm, the distance between the working and counter electrodes does not affect impedance measurements. However, the distance should be large enough to prevent the …

Chelator-Free Radiolabeling Of Serrs Nanoparticles For Whole-Body Pet And Intraoperative Raman Imaging, Matthew A. Wall, Travis Shaffer, Stefan Harmsen, Darjus-Felix Tschaharganeh, Chun-Hao Huang, Scott W. Lowe, Charles Michael Drain, Moritz F. Kircher

Publications and Research

A single contrast agent that offers whole-body non-invasive imaging along with the superior sensitivity and spatial resolution of surface-enhanced resonance Raman scattering (SERRS) imaging would allow both pre-operative mapping and intraoperative imaging and thus be highly desirable. We hypothesized that labeling our recently reported ultrabright SERRS nanoparticles with a suitable radiotracer would enable pre-operative identification of regions of interest with whole body imaging that can be rapidly corroborated with a Raman imaging device or handheld Raman scanner in order to provide high precision guidance during surgical procedures. Here we present a straightforward new method that produces radiolabeled SERRS nanoparticles for …

Insights Into The Binding Mode Of Mek Type-Iii Inhibitors. A Step Towards Discovering And Designing Allosteric Kinase Inhibitors Across The Human Kinome, Zheng Zhao, Lei Xie, Philip E. Bourne

Publications and Research

Protein kinases are critical drug targets for treating a large variety of human diseases. Type- III kinase inhibitors have attracted increasing attention as highly selective therapeutics. Thus, understanding the binding mechanism of existing type-III kinase inhibitors provides useful insights into designing new type-III kinase inhibitors. In this work, we have systematically studied the binding mode of MEK-targeted type-III inhibitors using structural systems pharmacology and molecular dynamics simulation. Our studies provide detailed sequence, structure, interaction-fingerprint, pharmacophore and binding-site information on the binding characteristics of MEK type-III kinase inhibitors. We hypothesize that the helix-folding activation loop is a hallmark allosteric binding site …

Toward Measuring Network Aesthetics Based On Symmetry, Zengqiang Chen, Matthias Dehmer, Frank Emmert-Streib, Abbe Mowshowitz, Yongtang Shi

Publications and Research

In this exploratory paper, we discuss quantitative graph-theoretical measures of network aesthetics. Related work in this area has typically focused on geometrical features (e.g., line crossings or edge bendiness) of drawings or visual representations of graphs which purportedly affect an observer’s perception. Here we take a very different approach, abandoning reliance on geometrical properties, and apply information-theoretic measures to abstract graphs and networks directly (rather than to their visual representaions) as a means of capturing classical appreciation of structural symmetry. Examples are used solely to motivate the approach to measurement, and to elucidate our symmetry-based mathematical theory of network aesthetics.

A Drosophila Model To Examine Collective Migration During Retinogenesis, Caroline Pena, Stephanie Zhang, Mildred Kamara, Tadmiri Venkatesh, Maribel Vazquez

Publications and Research

Retinal dysfunction is often caused by aberrant neural cell migration during development. In this study, we observed the migration of neural cells of the Drosophila melanogaster after marking cells of the 3rd instar larvae with the GAL4-UAS expression system when exposed to a concentration gradient of FGF-8 through the use of a microfluidic device. The glial and neuronal cell ratio in the developing brain was determined through immunofluorescent staining and observation. In future studies, a microfluidic device that mimics the developing Drosophila brain and retina will be designed in order to better understand the biological factors that affect the migration …

Collective Behaviour In Video Viewing: A Thermodynamic Analysis Of Gaze Position, Kate Burleson-Lesser, Flaviano Morone, Paul Deguzman, Lucas C. Parra, Hernan Makse

Publications and Research

Videos and commercials produced for large audiences can elicit mixed opinions. We wondered whether this diversity is also reflected in the way individuals watch the videos. To answer this question, we presented 65 commercials with high production value to 25 individuals while recording their eye movements, and asked them to provide preference ratings for each video. We find that gaze positions for the most popular videos are highly correlated. To explain the correlations of eye movements, we model them as ªinteractionsº between individuals. A thermodynamic analysis of these interactions shows that they approach a ªcritical º point such that any …

Multi-Scale Assessment Of Bone Mechanics And The Mineral Phase Of Intramuscular Bone Of Atlantic Herring Fish, Svetlana Zeveleva

Dissertations and Theses

Bone tissue is a complex composite structure made up of a soft organic phase consisting of collagen I and non-collagenous proteins, and a hard inorganic phase consisting of mineral nanoplatelets. Given it’s compositional properties, bone is a unique stiff, tough, and strong biomaterial, making it exceptionally difficult to synthesize ex vivo. While the complete hierarchical structure may change with age and population, the basic building block components of mineralized collagen fibrils, are preserved. This study uses a model of intramuscular bone of the Atlantic herring fish, which present a simple structure, and no process of remodeling.

A multi-scale approach …

Automatic Optimum Atlas Selection For Multi-Atlas Image Segmentation Using Joint Label Fusion, Kofi Agyeman

Dissertations and Theses

Multi-atlas image segmentation using label fusion is one of the most accurate state of the art image segmentation techniques available for biomedical imaging applications. Motivated to achieve higher image segmentation accuracy, reduce computational costs and a continuously increasing atlas data size, a robust framework for optimum selection of atlases for label fusion is vital. Although believed not to be critical for weighted label fusion techniques by some works (Sabuncu, M. R. et al., 2010, [1]), others have shown that appropriate atlas selection has several merits and can improve multi-atlas image segmentation accuracy (Aljabar et al., 2009, [2], Van de Velde …

Influence Of Fibroblasts On Metastatic Cancer Cell Drug Resistance In A 3d Microfluidic Cell Array, Elizabeth C. Benoy

Dissertations and Theses

Modeling an accurate depiction of the tumor microenvironment, (TME), is essential to observe the effect external factors might have on the tumor in vivo. In cancer therapy specifically, the outcomes of clinical treatments are heavily dependent on drug testing methods despite the cytotoxic effects these methods might have on the patient. Our lab has previously developed a three layered microfluidic cell array (3D μFCA) to reconstruct the relevantly spatial configuration of tumor and microvasculature found in vivo in order to develop a more efficient tool of high throughput drug discovery and screening. In this study, we optimized this device to …

Design Development And Performance Study Of A Novel Assistive Device For Mobility Of Toddlers And Children With Visual Impairments, Joowon Jun

Dissertations and Theses

Being able to see allows mankind tremendous access to learn about the world, and because so much learning comes visually, children with visual impairments are delayed in developing range of skills: learning own languages, doing activities, socializing with peers, and etc. While children with vision can do virtually all the activities and tasks for granted, children with visual impairment require different types of tools or materials to do same tasks most of time. Amongst all the disadvantages that children with visual impairment have, one of the most critical disadvantageous area that visual impairment brings to toddler is learning to walk. …