Molecular, Cellular, and Tissue Engineering Commons^™

In Vitro Antioxidant Oxidative Stress Treatment Model In Microgravity, Matt Clegg, Charles P. Harding, Taylor Clegg, Jon Takemoto, Elizabeth Vargis

Biomedical Engineering Western Regional Conference

We propose that the use of individual or a combination of antioxidants (specifically DL-alpha tocopherol phosphate disodium salt, mesobiliverdin, and L-glutathione) with astronauts in microgravity will reduce the effects of oxidative stress caused by ionizing radiation and muscular atrophy.

Molecular Modeling Of Antibody-Antigen Binding Near Solid Surfaces, Derek Bush, Thomas Knotts

Biomedical Engineering Western Regional Conference

Antibody microarrays are biosensors that have the potential to revolutionize molecular detection in medicine, scientific research, and national defense. However, current microarrays are not widely used due to problems including poor reproducibility and signal quality, unbalanced antibody performance, and cross-reactivity. Prior work in the area focused mainly on the stability of the antibody alone and not its affinity for its antigen. This presentation shows results of using molecular simulation to determine how different types of surfaces affect antigen binding to surface-tethered antibodies. The results offer an unprecedented, molecular-level view into these protein-protein-surface interactions and how to drive binding to occur.

Engineering A Fluorescent Protease Sensor For In Vivo Protein Detection, Thomas C. Kinard

Honors Scholar Theses

This report details the results of an ongoing project to engineer a mutant form of Red Fluorescent Protein (RFP) variant mCherry that acts as a real-time in vivo protease sensor. The sought-after mutant only becomes fluorescent when exposed to Tobacco Etch Virus (TEV) Protease, this system’s model protease. This will be accomplished via the insertion of the TEV Protease Recognition Site (TEV-PRS) in such a position that, before cleavage, will prevent the protein from folding to fluorescent conformation, but upon cleavage, will allow for fluorescent conformation to occur. The cylindrical structure of the protein, composed of beta-pleated sheets, contains “loops” …

Assessing Dprestin & Nadc1 (Indy) Interaction On Calcium Oxalate Crystal Formation In A Drosophila Model Of Kidney Stones, Jessica Lin

Undergraduate Research Symposium Posters

Calcium oxalate (CaOx) accounts for >70%of kidney stones, yet why CaOx stones form is poorly understood. While several factors contribute to the stone aggregation and growth, elucidating the roles of oxalate transporters can help demystify this phenomenon. Using a Drosophila model to study the formation and inhibition of CaOx crystals in the fly Malpighian tubule (MT), oxalate transport via dPrestin—the fly Slc26a6 Cl^-/Ox^2- exchanger was studied using both electrophysiology and MT dissection with CaOx birefringence assays. Here, the fly model suffices as it recapitulates renal oxalate excretion. Additionally, the mammalian dicarboxylate transporter NaDC1 (Indy in Drosophila) …

The Effect Of Tgfβ-1 On Adipose-Derived Stem Cell (Asc) Ring Constructs, Ashley C. Apil

Research Opportunities for Engineering Undergraduates (ROEU) Program 2016-17

Adipose-derived Stem Cells (ASC’s) provide an optimal source for potentially graft replacing, tissue-engineered vessel constructs due to their ease of extraction and ability to be patient-specific. In order to make ASC ring constructs a more viable replacement for grafts, they need to have mechanical properties similar to native arteries, which is largely influenced by the extracellular matrix protein collagen. TGFβ-1 is known to stimulate collagen production in ASC’s, so this study explores the effect that TGFβ-1 has on the resulting thickness and tensile strength of ASC ring constructs.

Evolutionary History Of Chemosensory-Related Gene Families Across The Arthropoda, Seong-Il Eyun, Ho Young Soh, Marijan Posavi, James B. Munro, Daniel S.T. Hughes, Shwetha C. Murali, Jiaxin Qu, Shannon Dugan, Sandra L. Lee, Hsu Chao, Huyen Dinh, Yi Han, Harshavardhan Doddapaneni, Kim C. Worley, Donna M. Muzny, Eun-Ok Park, Joana C. Silva, Richard A. Gibbs, Stephen Richards, Carol Eunmi Lee

Nebraska Center for Biotechnology: Faculty and Staff Publications

Chemosensory-related gene (CRG) families have been studied extensively in insects, but their evolutionary history across the Arthropoda had remained relatively unexplored. Here, we address current hypotheses and prior conclusions on CRG family evolution using a more comprehensive data set. In particular, odorant receptors were hypothesized to have proliferated during terrestrial colonization by insects (hexapods), but their association with other pancrustacean clades and with independent terrestrial colonizations in other arthropod subphyla have been unclear. We also examine hypotheses on which arthropod CRG family is most ancient. Thus, we reconstructed phylogenies of CRGs, including those from new arthropod genomes and transcriptomes, and …

The Effects Of Exercise And An Enhanced Nerve Conduit On Peripheral Nerve Injury, Anthony R. Mora

Research Opportunities for Engineering Undergraduates (ROEU) Program 2016-17

The primary objective of this effort is to quantify peripheral nerve recovery as a result of exposure to a multimodal conduit in addition to exercise. Quantification was based on behavioral data collected from a rat sciatic nerve model.

Phylogenomic Analysis Of Copepoda (Arthropoda, Crustacea) Reveals Unexpected Similarities With Earlier Proposed Morphological Phylogenies, Seong-Il Eyun

Nebraska Center for Biotechnology: Faculty and Staff Publications

Background: Copepods play a critical role in marine ecosystems but have been poorly investigated in phylogenetic studies. Morphological evidence supports the monophyly of copepods, whereas interordinal relationships continue to be debated. In particular, the phylogenetic position of the order Harpacticoida is still ambiguous and inconsistent among studies. Until now, a small number of molecular studies have been done using only a limited number or even partial genes and thus there is so far no consensus at the order-level.

Results: This study attempted to resolve phylogenetic relationships among and within four major copepod orders including Harpacticoida and the phylogenetic position of …

Modulating The Innate Immune Response To Electrospun Scaffolds And Polymer Degradative Byproducts, Daniel Abebayehu

Theses and Dissertations

Implanted biomaterials often induce inflammation that frequently leads to the foreign body response, fibrosis, and the failure of the implant. Thus, it is important to evaluate how cells interact with materials to promote a more regenerative response. It is critical to determine how to modulate the response of tissue resident innate immune cells, as they are among the first cells to interact with implanted materials. Among tissue resident innate immune cells are mast cells, which are inflammatory sentinels that degranulate and orchestrate the fate of other cell populations, such as monocytes/macrophages and lymphocytes. Mast cells have also been reported to …

Quantifying The Effects Of Hydrostatic Pressure On Fibroblast Growth Factor-2 Binding By The Human Endothelium, Taylor R. Mckenty

Theses and Dissertations--Biomedical Engineering

Fluid pressures regulate endothelial cell (EC) tubulogenic activity involving fibroblast growth factor 2 (FGF-2) and its receptor, FGF receptor 2 (FGFR2). Our lab has recently shown that sustained 20 mmHg hydrostatic pressure (HP) upregulates EC sprout formation in a FGF2-dependent fashion. This upregulation of sprout formation may be due to enhanced FGF-2 / FGFR2 interactions in the presence of 20 mmHg HP. We hypothesize that exposure of ECs to 20 mmHg sustained HP enhances FGF-2 binding kinetics. We used a custom hydrostatic pressure system, immunofluorescence, and FACS to quantify FGF-2 binding by ECs in the absence or presence of a …

A 3d Biomimetic Scaffold Using Electrospinning For Tissue Engineering Applications, Samerender Nagam Hanumantharao

Dissertations, Master's Theses and Master's Reports

Electrospinning holds great promise for designing functional 3D biomimetic scaffolds for tissue engineering applications. The technique allows for the reproducible fabrication of 3D scaffolds with control over the porosity and thickness. In this work, a novel method for the synthesis of a 3D electroactive scaffold using electrospinning from polycaprolactone (PCL), Polyvinylidene Fluoride (PVDF) and Polyaniline (PANI) is reported. Additional scaffolds involving different morphologies of PCL, PCL-PVDF and PCL-PANI-PVDF were also fabricated and evaluated. The scaffolds were characterized using electron microscopy to visualize the morphologies. Infrared spectroscopy was used to confirm the presence of polymers and their respective phases in the …

Developing Afm Techniques For Testing Peg Hydrogels, Hannah L. Cebull, Jessica Stukel, Rebecca Willits

Williams Honors College, Honors Research Projects

Many instruments are used to find elastic properties of biological samples using methods such as tensile and bending tests, but using the atomic force microscope (AFM) is considered a non-destructive method because it can provide repeated local stiffness information without damaging the sample. It additionally allows the sample to be tested in an aqueous environment, which is optimal for soft materials such as hydrogels. The nanoindentation is performed via cantilever, measuring the deflection of the cantilever during the contact of the sample using a laser. Compared to hard samples, testing soft materials can present more challenges when working with the …

Development And Validation Of A Novel Resonant Energy Transfer (Fret) Biosensor To Measure Tensile Forces At The Linc Complex In Live Cells, Paul Arsenovic

Theses and Dissertations

There is a large body of evidence supporting the theory that cell physiology largely depends on the mechanical properties of its surroundings or micro-environment. More recently studies have shown that changes to intra-cellular mechanical properties can also have a meaningful impact on cell function and in some cases lead to the progression of ailments or disease. For example, small changes to the protein sequence of a structural nuclear envelope protein called lamin-A is known to cause a variety of neurological and musculoskeletal diseases referred to as laminopathies. Currently, there is little incite into how these mutations lead to disease progression …

Development Of An Electrospun And 3d Printed Cellular Delivery Device For Dermal Wound Healing, Ryan M. Clohessy

Theses and Dissertations

The goal of this research was to develop a system of individualized medicine that could be applied to dermal wounds serving as a wound dressing and synthetic extracellular matrix while delivering stem cells to the wound bed. First, fabrication parameters for electrospinning polymer fibers were determined. This involved evaluating fiber morphology with respect to polymer selection and solution concentration. Next, construct fabrication was examined to produce an integrated void space, or cargo area, suitable to maintain stem cells. In vitro studies to ensure stem cell viability and phenotype were conducted, and results supported the notion that cells could be administered …

Characterization Of Molecular Communication Based On Cell Metabolism Through Mutual Information And Flux Balance Analysis, Zahmeeth Sayed Sakkaff

School of Computing: Dissertations, Theses, and Student Research

Synthetic biology is providing novel tools to engineer cells and access the basis of their molecular information processing, including their communication channels based on chemical reactions and molecule exchange. Molecular communication is a discipline in communication engineering that studies these types of communications and ways to exploit them for novel purposes, such as the development of ubiquitous and heterogeneous communication networks to interconnect biological cells with nano and biotechnology-enabled devices, i.e., the Internet of Bio-Nano Things. One major problem in realizing these goals stands in the development of reliable techniques to control the engineered cells and their behavior from the …

Scaffold And Tissue Based Therapies To Improve Skeletal Muscle Regeneration After Volumetric Muscle Loss, Benjamin Kasukonis

Graduate Theses and Dissertations

Volumetric muscle loss (VML) is an injury to skeletal muscle characterized by a loss of more than 20% of a muscles volume. The combination of the bulk loss of tissue, transection and separation of myofibers proximal and distal to the injury, loss of innervation and blood supply, and the depletion of muscle progenitor cells results in permanent fibrosis and functional deficits due to loss of contractile tissue. Scaffolds, cells, and engineered constructs have been explored as potential therapeutic interventions to induce myogenesis at the site of a VML injury in animal models, in addition to limited clinical trials. This dissertation …

Surface Engineering Of Titanium Alloy To Stimulate The Bone Regeneration, Yubin Meng, Zhenduo Cui, Zhaoyang Li, Xue Li, Jin Zhao, Xubo Yuan, Xianjin Yang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Ionic Basis Of Ventricular Action Potentials, Ariel L. Escobar

Science Seminar Series

Dr. Escobar will talk about his cutting-edge approach to understanding molecular mechanisms underlying electrical activity in the heart.

Characterization Of Histological Changes In The Microvasculature Of Rat Skeletal Muscle After Spinal Cord Injury, Sally Lin

Master's Theses (2009 -)

The purpose of this study was to determine whether there are histological changes in the microvasculature of rat skeletal muscle following chronic spinal cord injury both above and below the level of injury. This study is important because microvascular structure likely impacts muscle performance and cardiovascular health. To the best of our knowledge, this is the only study to investigate microvascular structure within rat skeletal muscle after spinal cord injury. We hypothesized structural remodeling would occur in both the myofibers and microvasculature, which would then manifest in differences in myofiber cross sectional area and microvascular diameter, wall thickness, wall to …

Bone Tissue Engineering: Scalability And Optimization Of Densified Collagen-Fibril Bone Graft Substitute Materials, John G. Nicholas, Lauren E. Watkins, Sherry L. Voytik-Harbin

The Summer Undergraduate Research Fellowship (SURF) Symposium

Over 240 million people missing teeth worldwide experience lingering problems such as difficulty speaking and eating, undesirable aesthetics, and resorption of bone supporting neighboring teeth. The gold standard of treatment utilizes grafts to attach a function-restoring implant to supporting bone. Current graft materials suffer from problems including autologous donor site morbidity, long resorption time, incomplete integration with the maxillae or mandible, and structural weakness. Patient-specific, cellularized bone grafts may be a solution to these issues by accelerating and improving the quality of regenerated bone. Recently, encapsulation of mesenchymal stem cells within self-assembling type I collagen oligomer matrices has been shown …