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Full-Text Articles in Biotechnology

A Review Of Threat Vectors To Dna Sequencing Pipelines, Tyler Rector Dec 2023

A Review Of Threat Vectors To Dna Sequencing Pipelines, Tyler Rector

Cybersecurity Undergraduate Research Showcase

Bioinformatics is a steadily growing field that focuses on the intersection of biology with computer science. Tools and techniques developed within this field are quickly becoming fixtures in genomics, forensics, epidemiology, and bioengineering. The development and analysis of DNA sequencing and synthesis have enabled this significant rise in demand for bioinformatic tools. Notwithstanding, these bioinformatic tools have developed in a research context free of significant cybersecurity threats. With the significant growth of the field and the commercialization of genetic information, this is no longer the case. This paper examines the bioinformatic landscape through reviewing the biological and cybersecurity threats within …


Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer Jan 2023

Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer

Electrical & Computer Engineering Faculty Publications

Microfluidic devices are increasingly utilized in numerous industries, including that of medicine, for their abilities to pump and mix fluid at a microscale. Within these devices, microchannels paired with microelectrodes enable the mixing and transportation of ionized fluid. The ionization process charges the microchannel and manipulates the fluid with an electric field. Although complex in operation at the microscale, microchannels within microfluidic devices are easy to produce and economical. This paper uses simulations to convey helpful insights into the analysis of electrokinetic microfluidic device phenomena. The simulations in this paper use the Navier–Stokes and Poisson Nernst–Planck equations solved using COMSOL …


Covid-19 And Biocybersecurity's Increasing Role On Defending Forward, Xavier Palmer, Lucas N. Potter, Saltuk Karahan Jan 2021

Covid-19 And Biocybersecurity's Increasing Role On Defending Forward, Xavier Palmer, Lucas N. Potter, Saltuk Karahan

Electrical & Computer Engineering Faculty Publications

The evolving nature of warfare has been changing with cybersecurity and the use of advanced biotechnology in each aspect of the society is expanding and overlapping with the cyberworld. This intersection, which has been described as “biocybersecurity” (BCS), can become a major front of the 21st-century conflicts. There are three lines of BCS which make it a critical component of overall cybersecurity: (1) cyber operations within the area of BCS have life threatening consequences to a greater extent than other cyber operations, (2) the breach in health-related personal data is a significant tool for fatal attacks, and (3) health-related misinformation …


Numerical Modeling Of Submicron Particles For Acoustic Concentration In Gaseous Flow, Jizhou Liu, Xiaodong Li, Fang Q. Hu Jan 2020

Numerical Modeling Of Submicron Particles For Acoustic Concentration In Gaseous Flow, Jizhou Liu, Xiaodong Li, Fang Q. Hu

Mathematics & Statistics Faculty Publications

This paper intends to explore the rationality and feasibility of modeling dispersed submicron particles in air by a kinetic-based method called the unified gas-kinetic scheme (UGKS) and apply it to the simulation of particle concentration under a transverse standing wave. A gas-particle coupling scheme is proposed where the gas phase is modeled by the two-dimensional linearized Euler equations (LEE) and, through the analogous behavior between the rarefied gas molecules and the air-suspended particles, a modified UGKS is adopted to estimate the particle dynamics. The Stokes' drag force and the acoustic radiation force applied on particles are accounted for by introducing …


Deepep: A Deep Learning Framework For Identifying Essential Proteins, Min Zeng, Min Li, Fang-Xiang Wu, Yaohang Li, Yi Pan Dec 2019

Deepep: A Deep Learning Framework For Identifying Essential Proteins, Min Zeng, Min Li, Fang-Xiang Wu, Yaohang Li, Yi Pan

Computer Science Faculty Publications

Background: Essential proteins are crucial for cellular life and thus, identification of essential proteins is an important topic and a challenging problem for researchers. Recently lots of computational approaches have been proposed to handle this problem. However, traditional centrality methods cannot fully represent the topological features of biological networks. In addition, identifying essential proteins is an imbalanced learning problem; but few current shallow machine learning-based methods are designed to handle the imbalanced characteristics. Results: We develop DeepEP based on a deep learning framework that uses the node2vec technique, multi-scale convolutional neural networks and a sampling technique to identify essential proteins. …


Label-Free Microrna Optical Biosensors, Meimei Lai, Gymama Slaughter Nov 2019

Label-Free Microrna Optical Biosensors, Meimei Lai, Gymama Slaughter

Bioelectrics Publications

MicroRNAs (miRNAs) play crucial roles in regulating gene expression. Many studies show that miRNAs have been linked to almost all kinds of disease. In addition, miRNAs are well preserved in a variety of specimens, thereby making them ideal biomarkers for biosensing applications when compared to traditional protein biomarkers. Conventional biosensors for miRNA require fluorescent labeling, which is complicated, time-consuming, laborious, costly, and exhibits low sensitivity. The detection of miRNA remains a big challenge due to their intrinsic properties such as small sizes, low abundance, and high sequence similarity. A label-free biosensor can simplify the assay and enable the direct detection …


Acute Systemic Inflammatory Response To Lipopolysaccharide Stimulation In Pigs Divergently Selected For Residual Feed Intake, Haibo Liu, Kristina M. Feye, Yet T. Nguyen, Anoosh Rakhshandeh, Crystal L. Loving, Jack C. M. Sekkers, Nicholas K. Gabler, Christopher K. Tuggle Oct 2019

Acute Systemic Inflammatory Response To Lipopolysaccharide Stimulation In Pigs Divergently Selected For Residual Feed Intake, Haibo Liu, Kristina M. Feye, Yet T. Nguyen, Anoosh Rakhshandeh, Crystal L. Loving, Jack C. M. Sekkers, Nicholas K. Gabler, Christopher K. Tuggle

Mathematics & Statistics Faculty Publications

Background: It is unclear whether improving feed efficiency by selection for low residual feed intake (RFI) compromises pigs’ immunocompetence. Here, we aimed at investigating whether pig lines divergently selected for RFI had different inflammatory responses to lipopolysaccharide (LPS) exposure, regarding to clinical presentations and transcriptomic changes in peripheral blood cells.

Results: LPS injection induced acute systemic inflammation in both the low-RFI and high-RFI line (n = 8 per line). At 4 h post injection (hpi), the low-RFI line had a significantly lower (p= 0.0075) mean rectal temperature compared to the high-RFI line. However, no significant differences in complete blood count …


Mechanisms And Immunogenicity Of Nspef-Induced Cell Death In B16f10 Melanoma Tumors, Alessandra Rossi, Olga N. Pakhomova, Andrei G. Pakhomov, Samantha Weygandt, Anna A. Bulysheva, Len E. Murray, Peter A. Mollica, Claudia Muratori Jan 2019

Mechanisms And Immunogenicity Of Nspef-Induced Cell Death In B16f10 Melanoma Tumors, Alessandra Rossi, Olga N. Pakhomova, Andrei G. Pakhomov, Samantha Weygandt, Anna A. Bulysheva, Len E. Murray, Peter A. Mollica, Claudia Muratori

Bioelectrics Publications

Accumulating data indicates that some cancer treatments can restore anticancer immunosurveillance through the induction of tumor immunogenic cell death (ICD). Nanosecond pulsed electric fields (nsPEF) have been shown to efficiently ablate melanoma tumors. In this study we investigated the mechanisms and immunogenicity of nsPEF-induced cell death in B16F10 melanoma tumors. Our data show that in vitro nsPEF (20-200, 200-ns pulses, 7 kV/cm, 2 Hz) caused a rapid dose-dependent cell death which was not accompanied by caspase activation or PARP cleavage. The lack of nsPEF-induced apoptosis was confirmed in vivo in B16F10 tumors. NsPEF also failed to trigger ICD-linked responses such …


A 3d Bioprinter Platform For Mechanistic Analysis Of Tumoroids And Chimeric Mammary Organoids, John A. Reid, Xavier-Lewis Palmer, Peter A. Mollica, Nicole Northam, Patrick C. Sachs, Robert D. Bruno Jan 2019

A 3d Bioprinter Platform For Mechanistic Analysis Of Tumoroids And Chimeric Mammary Organoids, John A. Reid, Xavier-Lewis Palmer, Peter A. Mollica, Nicole Northam, Patrick C. Sachs, Robert D. Bruno

Medical Diagnostics & Translational Sciences Faculty Publications

The normal mammary microenvironment can suppress tumorigenesis and redirect cancer cells to adopt a normal mammary epithelial cell fate in vivo. Understanding of this phenomenon offers great promise for novel treatment and detection strategies in cancer, but current model systems make mechanistic insights into the process difficult. We have recently described a low-cost bioprinting platform designed to be accessible for basic cell biology laboratories. Here we report the use of this system for the study of tumorigenesis and microenvironmental redirection of breast cancer cells. We show our bioprinter significantly increases tumoroid formation in 3D collagen gels and allows for precise …


Consistent And Reproducible Cultures Of Large-Scale 3d Mammary Epithelial Structures Using An Accessible Bioprinting Platform, John A. Reid, Peter M. Mollica, Robert D. Bruno, Patrick C. Sachs Oct 2018

Consistent And Reproducible Cultures Of Large-Scale 3d Mammary Epithelial Structures Using An Accessible Bioprinting Platform, John A. Reid, Peter M. Mollica, Robert D. Bruno, Patrick C. Sachs

Medical Diagnostics & Translational Sciences Faculty Publications

Background: Standard three-dimensional (3D) in vitro culture techniques, such as those used for mammary epithelial cells, rely on random distribution of cells within hydrogels. Although these systems offer advantages over traditional 2D models, limitations persist owing to the lack of control over cellular placement within the hydrogel. This results in experimental inconsistencies and random organoid morphology. Robust, high-throughput experimentation requires greater standardization of 3D epithelial culture techniques.

Methods: Here, we detail the use of a 3D bioprinting platform as an investigative tool to control the 3D formation of organoids through the "self-assembly" of human mammary epithelial cells. Experimental bioprinting procedures …


Moderate Heat Application Enhances The Efficacy Of Nanosecond Pulse Stimulation For The Treatment Of Squamous Cell Carcinoma, Chelsea M. Edelblute, Sigi Guo, Embo Yang, Chunqi Jiang, Karl Schoenbach, Richard Heller Sep 2018

Moderate Heat Application Enhances The Efficacy Of Nanosecond Pulse Stimulation For The Treatment Of Squamous Cell Carcinoma, Chelsea M. Edelblute, Sigi Guo, Embo Yang, Chunqi Jiang, Karl Schoenbach, Richard Heller

Bioelectrics Publications

Nanosecond pulse stimulation as a tumor ablation therapy has been studied for the treatment of various carcinomas in animal models and has shown a significant survival benefit. In the current study, we found that moderate heating at 43°C for 2 minutes significantly enhanced in vitro nanosecond pulse stimulation-induced cell death of KLN205 murine squamous cell carcinoma cells by 2.43-fold at 600 V and by 2.32-fold at 900 V, as evidenced by propidium iodide uptake. Furthermore, the ablation zone in KLN205 cells placed in a 3-dimensional cell-culture model and pulsed at a voltage of 900 V at 43°C was 3 times …


Mechanism Of Virus Inactivation By Cold Atmospheric-Pressure Plasma And Plasma-Activated Water, Li Guo, Ruobing Xu, Lu Gou, Zhichao Liu, Yiming Zhao, Dingxin Liu, Lei Zhang, Hailan Chen, Michael G. Kong Jun 2018

Mechanism Of Virus Inactivation By Cold Atmospheric-Pressure Plasma And Plasma-Activated Water, Li Guo, Ruobing Xu, Lu Gou, Zhichao Liu, Yiming Zhao, Dingxin Liu, Lei Zhang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

ABSTRACT Viruses cause serious pathogenic contamination that severely affects the environment and human health. Cold atmospheric-pressure plasma efficiently inactivates pathogenic bacteria; however, the mechanism of virus inactivation by plasma is not fully understood. In this study, surface plasma in argon mixed with 1% air and plasma-activated water was used to treat water containing bacteriophages. Both agents efficiently inactivated bacteriophages T4, ϕ174, and MS2 in a time-dependent manner. Prolonged storage had marginal effects on the antiviral activity of plasma-activated water. DNA and protein analysis revealed that the reactive species generated by plasma damaged both nucleic acids and proteins, consistent with the …


Prediction Of Lncrna-Disease Associations Based On Inductive Matrix Completion, Chengqian Lu, Mengyun Yang, Feng Luo, Fang-Xiang Wu, Min Li, Yi Pan, Yaohang Li, Jianxin Wang Apr 2018

Prediction Of Lncrna-Disease Associations Based On Inductive Matrix Completion, Chengqian Lu, Mengyun Yang, Feng Luo, Fang-Xiang Wu, Min Li, Yi Pan, Yaohang Li, Jianxin Wang

Computer Science Faculty Publications

Motivation: Accumulating evidences indicate that long non-coding RNAs (lncRNAs) play pivotal roles in various biological processes. Mutations and dysregulations of lncRNAs are implicated in miscellaneous human diseases. Predicting lncRNA–disease associations is beneficial to disease diagnosis as well as treatment. Although many computational methods have been developed, precisely identifying lncRNA–disease associations, especially for novel lncRNAs, remains challenging.

Results: In this study, we propose a method (named SIMCLDA) for predicting potential lncRNA– disease associations based on inductive matrix completion. We compute Gaussian interaction profile kernel of lncRNAs from known lncRNA–disease interactions and functional similarity of diseases based on disease–gene and gene–gene onotology …


Upregulation Of Dna Sensors In B16.F10 Melanoma Spheroid Cells After Electrotransfer Of Pdna, Katarina Znidar, Masa Bosnjak, Tanja Jesenko, Loree C. Heller, Maja Cemazar Jan 2018

Upregulation Of Dna Sensors In B16.F10 Melanoma Spheroid Cells After Electrotransfer Of Pdna, Katarina Znidar, Masa Bosnjak, Tanja Jesenko, Loree C. Heller, Maja Cemazar

Bioelectrics Publications

Increased expression of cytosolic DNA sensors, a category of pattern recognition receptor, after control plasmid DNA electrotransfer was observed in our previous studies on B16.F10 murine melanoma cells. This expression was correlated with the upregulation of proinflammatory cytokines and chemokines and was associated with cell death. Here, we expanded our research to include the influence of features of cells in a 3-dimensional environment, which better represents the tumors’ organization in vivo. Our results show that lower number of cells were transfected in spheroids compared to 2-dimensional cultures, that growth was delayed after electroporation alone or after electrotransfer of plasmid …


Cell Fragmentation And Permeabilization By A 1 Ns Pulse Driven Triple-Point Electrode, Enbo Yang, Joy Li, Michael Cho, Shu Xiao Jan 2018

Cell Fragmentation And Permeabilization By A 1 Ns Pulse Driven Triple-Point Electrode, Enbo Yang, Joy Li, Michael Cho, Shu Xiao

Bioelectrics Publications

Ultrashort electric pulses (ns-ps) are useful in gaining understanding as to how pulsed electric fields act upon biological cells, but the electric field intensity to induce biological responses is typically higher than longer pulses and therefore a high voltage ultrashort pulse generator is required. To deliver 1 ns pulses with sufficient electric field but at a relatively low voltage, we used a glass-encapsulated tungsten wire triple-point electrode (TPE) at the interface among glass, tungsten wire, and water when it is immersed in water. A high electric field (2MV/cm) can be created when pulses are applied. However, such a high electric …


Dielectric Properties Of Isolated Adrenal Chromaffin Cells Determined By Microfluidic Impedance Spectroscopy, A. C. Sabuncu, M. Stacey, G. L. Graviso, N. Semenova, P. T. Vernier, N. Leblanc, I. Chatterjee, J. Zaklit Jan 2018

Dielectric Properties Of Isolated Adrenal Chromaffin Cells Determined By Microfluidic Impedance Spectroscopy, A. C. Sabuncu, M. Stacey, G. L. Graviso, N. Semenova, P. T. Vernier, N. Leblanc, I. Chatterjee, J. Zaklit

Bioelectrics Publications

Knowledge of the dielectric properties of biological cells plays an important role in numerical models aimed at understanding how high intensity ultrashort nanosecond electric pulses affect the plasma membrane and the membranes of intracellular organelles. To this end, using electrical impedance spectroscopy, the dielectric properties of isolated, neuroendocrine adrenal chromaffin cells were obtained. Measured impedance data of the cell suspension, acquired between 1 kHz and 20 MHz, were fit into a combination of constant phase element and Cole-Cole models from which the effect of electrode polarization was extracted. The dielectric spectrum of each cell suspension was fit into a Maxwell-Wagner …


Electrotransfer Of Different Control Plasmids Elicits Different Antitumor Effectiveness In B16.F10 Melanoma, Masa Bosnjak, Tanjo Jesenko, Urska Kamensek, Gregor Sersa, Jaka Lavrencak, Loree Heller, Maja Cemazar Jan 2018

Electrotransfer Of Different Control Plasmids Elicits Different Antitumor Effectiveness In B16.F10 Melanoma, Masa Bosnjak, Tanjo Jesenko, Urska Kamensek, Gregor Sersa, Jaka Lavrencak, Loree Heller, Maja Cemazar

Bioelectrics Publications

Several studies have shown that different control plasmids may cause antitumor action in different murine tumor models after gene electrotransfer (GET). Due to the differences in GET protocols, plasmid vectors, and experimental models, the observed antitumor effects were incomparable. Therefore, the current study was conducted comparing antitumor effectiveness of three different control plasmids using the same GET parameters. We followed cytotoxicity in vitro and the antitumor effect in vivo after GET of control plasmids pControl, pENTR/U6 scr and pVAX1 in B16.F10 murine melanoma cells and tumors. Types of cell death and upregulation of selected cytosolic DNA sensors and cytokines were …


Excitation And Injury Of Adult Ventricular Cardiomyocytes By Nano- To Millisecond Electric Shocks, Iurii Semenov, Sergey Grigoryev, Johanna U. Neuber, Christian W. Zemlin, Olga N. Pakhomova, Maura Casciola, Andrei G. Pakhomov Jan 2018

Excitation And Injury Of Adult Ventricular Cardiomyocytes By Nano- To Millisecond Electric Shocks, Iurii Semenov, Sergey Grigoryev, Johanna U. Neuber, Christian W. Zemlin, Olga N. Pakhomova, Maura Casciola, Andrei G. Pakhomov

Bioelectrics Publications

Intense electric shocks of nanosecond (ns) duration can become a new modality for more efficient but safer defibrillation. We extended strength-duration curves for excitation of cardiomyocytes down to 200 ns, and compared electroporative damage by proportionally more intense shocks of different duration. Enzymatically isolated murine, rabbit, and swine adult ventricular cardiomyocytes (VCM) were loaded with a Ca2+ indicator Fluo-4 or Fluo-5N and subjected to shocks of increasing amplitude until a Ca2+ transient was optically detected. Then, the voltage was increased 5-fold, and the electric cell injury was quantified by the uptake of a membrane permeability marker dye, propidium …


Nano-Pulse Stimulation For The Treatment Of Pancreatic Cancer And The Changes In Immune Profile, Sigi Guo, Niculina I. Burcus, James Hornef, Yu Jing, Chunqi Jiang, Richard Heller, Stephen J. Beebe Jan 2018

Nano-Pulse Stimulation For The Treatment Of Pancreatic Cancer And The Changes In Immune Profile, Sigi Guo, Niculina I. Burcus, James Hornef, Yu Jing, Chunqi Jiang, Richard Heller, Stephen J. Beebe

Bioelectrics Publications

A Pancreatic cancer is a notorious malignant neoplasm with an extremely poor prognosis. Current standard of care is rarely effective against late-stage pancreatic cancer. In this study, we assessed nanopulse stimulation (NPS) as a local treatment for pancreatic cancer in a syngeneic mouse Pan02 pancreatic cancer model and characterized corresponding changes in the immune profile. A single NPS treatment either achieved complete tumor regression or prolonged overall survival in animals with partial tumor regression. While this is very encouraging, we also explored if this local ablation effect could also result in immune stimulation, as was observed when NPS led to …


High-Throughput Single-Molecule Telomere Characterization, Jennifer Mccaffrey, Eleanor Young, Katy Lassahn, Justin Sibert, Steven Pastor, Harold Riethman, Ming Xiao Nov 2017

High-Throughput Single-Molecule Telomere Characterization, Jennifer Mccaffrey, Eleanor Young, Katy Lassahn, Justin Sibert, Steven Pastor, Harold Riethman, Ming Xiao

Medical Diagnostics & Translational Sciences Faculty Publications

We have developed a novel method that enables global subtelomere and haplotype-resolved analysis of telomere lengths at the single-molecule level. An in vitro CRISPR/Cas9 RNA-directed nickase system directs the specific labeling of human (TTAGGG) n DNA tracts in genomes that have also been barcoded using a separate nickase enzyme that recognizes a 7bp motif genome-wide. High-throughput imaging and analysis of large DNA single molecules from genomes labeled in this fashion using a nanochannel array system permits mapping through subtelomere repeat element (SRE) regions to unique chromosomal DNA while simultaneously measuring the (TTAGGG) n tract length at the end of each …


Delayed Hypersensitivity To Nanosecond Pulsed Electric Field In Electroporated Cells, Sarah D. Jensen, Vera A. Khorokhorina, Claudia Muratori, Andrei G. Pakhomov, Olga N. Pakhomova Sep 2017

Delayed Hypersensitivity To Nanosecond Pulsed Electric Field In Electroporated Cells, Sarah D. Jensen, Vera A. Khorokhorina, Claudia Muratori, Andrei G. Pakhomov, Olga N. Pakhomova

Bioelectrics Publications

We demonstrate that conditioning of mammalian cells by electroporation with nanosecond pulsed electric field (nsPEF) facilitates their response to the next nsPEF treatment. The experiments were designed to unambiguously separate the electroporation-induced sensitization and desensitization effects. Electroporation was achieved by bursts of 300-ns, 9 kV/cm pulses (50 Hz, n = 3–100) and quantified by propidium dye uptake within 11 min after the nsPEF exposure. We observed either sensitization to nsPEF or no change (when the conditioning was either too weak or too intense, or when the wait time after conditioning was too short). Within studied limits, conditioning never caused desensitization. …


Controllable Moderate Heating Enhances The Therapeutic Efficacy Of Irreversible Electroporation For Pancreatic Cancer, Chelsea M. Edelblute, James Hornef, Niculina I. Burcus, Thomas Norman, Stephen J. Beebe, Karl Schoenbach, Richard Heller, Chunqi Jiang, Sigi Guo Sep 2017

Controllable Moderate Heating Enhances The Therapeutic Efficacy Of Irreversible Electroporation For Pancreatic Cancer, Chelsea M. Edelblute, James Hornef, Niculina I. Burcus, Thomas Norman, Stephen J. Beebe, Karl Schoenbach, Richard Heller, Chunqi Jiang, Sigi Guo

Bioelectrics Publications

Irreversible electroporation (IRE) as a non-thermal tumor ablation technology has been studied for the treatment of pancreatic carcinoma and has shown a significant survival benefit. We discovered that moderate heating (MH) at 43°C for 1-2 minutes significantly enhanced ex vivo IRE tumor ablation of Pan02 cells by 5.67-fold at 750 V/cm and by 1.67-fold at 1500 V/cm. This amount of heating alone did not cause cell death. An integrated IRE system with controllable laser heating and tumor impedance monitoring was developed to treat mouse ectopic pancreatic cancer. With this novel IRE system, we were able to heat and maintain the …


Damage-Free Peripheral Nerve Stimulation By 12-Ns Pulsed Electric Field, Maura Casciola, Shu Xiao, Andrei G. Pakhomov Sep 2017

Damage-Free Peripheral Nerve Stimulation By 12-Ns Pulsed Electric Field, Maura Casciola, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Modern technologies enable deep tissue focusing of nanosecond pulsed electric field (nsPEF) for non-invasive nerve and muscle stimulation. However, it is not known if PEF orders of magnitude shorter than the activation time of voltage-gated sodium channels (VGSC) would evoke action potentials (APs). One plausible scenario requires the loss of membrane integrity (electroporation) and resulting depolarization as an intermediate step. We report, for the first time, that the excitation of a peripheral nerve can be accomplished by 12-ns PEF without electroporation. 12-ns stimuli at 4.1-11 kV (3.3-8.8 kV/cm) evoked APs similarly to conventional stimuli (100-250 mus, 1-5 V, 103-515 V/m), …


Multi-Material Mesh Representation Of Anatomical Structures For Deep Brain Stimulation Planning, Tanweer Rashid Jul 2017

Multi-Material Mesh Representation Of Anatomical Structures For Deep Brain Stimulation Planning, Tanweer Rashid

Computational Modeling & Simulation Engineering Theses & Dissertations

The Dual Contouring algorithm (DC) is a grid-based process used to generate surface meshes from volumetric data. However, DC is unable to guarantee 2-manifold and watertight meshes due to the fact that it produces only one vertex for each grid cube. We present a modified Dual Contouring algorithm that is capable of overcoming this limitation. The proposed method decomposes an ambiguous grid cube into a set of tetrahedral cells and uses novel polygon generation rules that produce 2-manifold and watertight surface meshes with good-quality triangles. These meshes, being watertight and 2-manifold, are geometrically correct, and therefore can be used to …


Hyper-Activation Of Pp60(Src) Limits Nitric Oxide Signaling By Increasing Asymmetric Dimethylarginine Levels During Acute Lung Injury, Sanjiv Kumar, Xutong Sun, Satish Kumar Noonepalle, Qing Lu, Evgeny Zemskov, Ting Wang, Saurabh Aggarwal, Christine Gross, Shruti Sharma, Ankit A. Sesai, John D. Catravas Jan 2017

Hyper-Activation Of Pp60(Src) Limits Nitric Oxide Signaling By Increasing Asymmetric Dimethylarginine Levels During Acute Lung Injury, Sanjiv Kumar, Xutong Sun, Satish Kumar Noonepalle, Qing Lu, Evgeny Zemskov, Ting Wang, Saurabh Aggarwal, Christine Gross, Shruti Sharma, Ankit A. Sesai, John D. Catravas

Bioelectrics Publications

The molecular mechanisms by which the endothelial barrier becomes compromised during lipopolysaccharide (LPS) mediated acute lung injury (ALI) are still unresolved. We have previously reported that the disruption of the endothelial barrier is due, at least in part, to the uncoupling of endothelial nitric oxide synthase (eNOS) and increased peroxynitrite-mediated nitration of RhoA. The purpose of this study was to elucidate the molecular mechanisms by which LPS induces eNOS uncoupling during ALI. Exposure of pulmonary endothelial cells (PAEC) to LPS increased pp60Src activity and this correlated with an increase in nitric oxide (NO) production, but also an increase in …


Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Monika Savarin, Urska Kamensek, Maja Cemazar, Richard Heller, Gregor Sersa Jan 2017

Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Monika Savarin, Urska Kamensek, Maja Cemazar, Richard Heller, Gregor Sersa

Bioelectrics Publications

Background. Tumor irradiation combined with adjuvant treatments, either vascular targeted or immunomodulatory, is under intense investigation. Gene electrotransfer of therapeutic genes is one of these approaches. The aim of this study was to determine, whether gene electrotransfer of plasmid encoding shRNA for silencing endoglin, with vascular targeted effectiveness, can radiosensitize melanoma B16F10 tumors.

Materials and methods. The murine melanoma Bl6F10 tumors, growing on the back of C57BI/6 mice, were treated by triple gene electrotransfer and irradiation. The antitumor effect was evaluated by determination of tumor growth delay and proportion of tumor free mice. Furthermore, histological analysis of tumors (necrosis, apoptosis, …


Tissue Specific Microenvironments: A Key Tool For Tissue Engineering And Regenerative Medicine, Patrick C. Sachs, Peter A. Mollica, Robert D. Bruno Jan 2017

Tissue Specific Microenvironments: A Key Tool For Tissue Engineering And Regenerative Medicine, Patrick C. Sachs, Peter A. Mollica, Robert D. Bruno

Medical Diagnostics & Translational Sciences Faculty Publications

The accumulated evidence points to the microenvironment as the primary mediator of cellular fate determination. Comprised of parenchymal cells, stromal cells, structural extracellular matrix proteins, and signaling molecules, the microenvironment is a complex and synergistic edifice that varies tissue to tissue. Furthermore, it has become increasingly clear that the microenvironment plays crucial roles in the establishment and progression of diseases such as cardiovascular disease, neurodegeneration, cancer, and ageing. Here we review the historical perspectives on the microenvironment, and how it has directed current explorations in tissue engineering. By thoroughly understanding the role of the microenvironment, we can begin to correctly …


Nanosecond Pulsed Electric Field Induced Changes In Cell Surface Charge Density, Diganta Dutta, Xavier-Lewis Palmer, Anthony Asmar, Michael Stacey, Shizhi Qian Jan 2017

Nanosecond Pulsed Electric Field Induced Changes In Cell Surface Charge Density, Diganta Dutta, Xavier-Lewis Palmer, Anthony Asmar, Michael Stacey, Shizhi Qian

Bioelectrics Publications

This study reports that the surface charge density changes in Jurkat cells with the application of single 60 nanosecond pulse electric fields, using atomic force microscopy. Using an atomic force microscope tip and Jurkat cells on silica in a 0.01 M KCl ionic concentration, we were able to measure the interfacial forces, while also predicting surface charge densities of both Jurkat cell and silica surfaces. The most important finding is that the pulsing conditions varyingly reduced the cells' surface charge density. This offers a novel way in which to examine cellular effects of pulsed electric fields that may lead to …


Modeling Beta-Traces For Beta-Barrels From Cryo-Em Density Maps, Dong Si, Jing He Jan 2017

Modeling Beta-Traces For Beta-Barrels From Cryo-Em Density Maps, Dong Si, Jing He

Computer Science Faculty Publications

Cryo-electron microscopy (cryo-EM) has produced density maps of various resolutions. Although ά-helices can be detected from density maps at 5-8 angstrom resolutions, β-strands are challenging to detect at such density maps due to close-spacing of β-strands. The variety of shapes of β-sheets adds the complexity of β-strands detection from density maps. We propose a new approach to model traces of β-strands for β-barrel density regions that are extracted from cryo-EM density maps. In the test containing eight β-barrels extracted from experimental cryo-EM density maps at 5.5 angstrom-8.25 angstrom resolution, StrandRoller detected about 74.26% of the amino acids in the β-strands …


Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He Jan 2017

Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He

Computer Science Faculty Publications

Three-dimensional density maps of biological specimens from cryo-electron microscopy (cryo-EM) can be interpreted in the form of atomic models that are modeled into the density, or they can be compared to known atomic structures. When the central axis of a helix is detectable in a cryo-EM density map, it is possible to quantify the agreement between this central axis and a central axis calculated from the atomic model or structure. We propose a novel arc-length association method to compare the two axes reliably. This method was applied to 79 helices in simulated density maps and six case studies using cryo-EM …