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Full-Text Articles in Biomedical Engineering and Bioengineering

Computational Analysis And Design Optimization Of Convective Pcr Devices, Jung Il Shu Jul 2019

Computational Analysis And Design Optimization Of Convective Pcr Devices, Jung Il Shu

Mechanical & Aerospace Engineering Theses & Dissertations

Polymerase Chain Reaction (PCR) is a relatively novel technique to amplify a few copies of DNA to a detectable level. PCR has already become common in biomedical research, criminal forensics, molecular archaeology, and so on. Many have attempted to develop PCR devices in numerous types for the purpose of the lab-on-chip (LOC) or point-of-care (POC). To use PCR devices for POC lab testing, the price must be lower, and the performance should be comparable to the lab devices. For current practices with the existing methods, the price is pushed up higher partially due to too much dependence on numerous developmental ...


Modulation Of Biological Responses To 2 Ns Electrical Stimuli By Field Reversal, Esin B. Sözer, P. Thomas Vernier Jun 2019

Modulation Of Biological Responses To 2 Ns Electrical Stimuli By Field Reversal, Esin B. Sözer, P. Thomas Vernier

Bioelectrics Publications

Nanosecond bipolar pulse cancellation, a recently discovered Phenomenon, is modulation of the effects of a unipolar electric pulse exposure by a second pulse of opposite polarity. This attenuation of biological response by reversal of the electric field direction has been reported with pulse durations from 60 ns to 900 ns for a wide range of endpoints, and it is not observed with conventional electroporation pulses of much longer duration (> 100 mu s) where pulses are additive regardless of polarity. The most plausible proposed mechanisms involve the field-driven migration of ions to and from the membrane interface (accelerated membrane discharge). Here ...


Estimating Cognitive Workload In An Interactive Virtual Reality Environment Using Electrophysiological And Kinematic Activity, Christoph Tremmel Apr 2019

Estimating Cognitive Workload In An Interactive Virtual Reality Environment Using Electrophysiological And Kinematic Activity, Christoph Tremmel

Biomedical Engineering Theses & Dissertations

As virtual reality (VR) technology continues to gain prominence in commercial, educational, recreational and research applications, there is increasing interest in incorporating physiological sensors in VR devices for passive user-state monitoring to eventually increase the sense of immersion. By recording physiological signals such as the electroencephalogram (EEG), electromyography (EMG) or kinematic parameters during the use of a VR device, the user’s interactions in the virtual environment could be adapted in real time based on the user’s cognitive state. This dissertation evaluates the feasibility of passively monitoring cognitive workload via electrophysiological and kinematic activity while performing a classical n-back ...


A Fully-Flexible Solution-Processed Autonomous Glucose Indicator, Jonathan D. Yuen, Ankit Baingane, Qumrul Hasan, Lisa C. Shriver-Lake, Scott A. Walper, Daniel Zabetakis, Joyce C. Breger, David A. Stenger, Gymama Slaughter Jan 2019

A Fully-Flexible Solution-Processed Autonomous Glucose Indicator, Jonathan D. Yuen, Ankit Baingane, Qumrul Hasan, Lisa C. Shriver-Lake, Scott A. Walper, Daniel Zabetakis, Joyce C. Breger, David A. Stenger, Gymama Slaughter

Bioelectrics Publications

We present the first demonstration of a fully-flexible, self-powered glucose indicator system that synergizes two flexible electronic technologies: a flexible self-powering unit in the form of a biofuel cell, with a flexible electronic device - a circuit-board decal fabricated with biocompatible microbial nanocellulose. Our proof-of-concept device, comprising an enzymatic glucose fuel cell, glucose sensor and a LED indicator, does not require additional electronic equipment for detection or verification; and the entire structure collapses into a microns-thin, self-adhering, single-centimeter-square decal, weighing less than 40 mg. The flexible glucose indicator system continuously operates a light emitting diode (LED) through a capacitive charge/discharge ...


Special Collection On Electroporation-Based Therapies: A Selection Of Papers From The Second World Congress On Electroporation, Richard Heller, Rafael V. Davalos Jan 2019

Special Collection On Electroporation-Based Therapies: A Selection Of Papers From The Second World Congress On Electroporation, Richard Heller, Rafael V. Davalos

Bioelectrics Publications

No abstract provided.


Effect Of Cold Atmospheric Plasma Treatment On The Metabolites Of Human Leukemia Cells, Dehui Xu, Ning Ning, Yujing Xu, Bingchuan Wang, Qingjie Cui, Zhijie Liu, Xiaohua Wang, Dingxin Liu, Hailan Chen, Michael G. Kong Jan 2019

Effect Of Cold Atmospheric Plasma Treatment On The Metabolites Of Human Leukemia Cells, Dehui Xu, Ning Ning, Yujing Xu, Bingchuan Wang, Qingjie Cui, Zhijie Liu, Xiaohua Wang, Dingxin Liu, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Background

Acute myeloid leukemia (AML) is a typically fatal malignancy and new drug and treatment need to be developed for a better survival outcome. Cold atmospheric plasma (CAP) is a novel technology, which has been widely applied in biomedicine, especially in various of cancer treatment. However, the changes in cell metabolism after CAP treatment of leukemia cells have been rarely studied.

Methods

In this study, we investigated the metabolite profiling of plasma treatment on leukemia cells based on Gas Chromatography Tandem Time-of-Flight Mass Spectrometry (GC-TOFMS). Simultaneously, we conducted a series of bioinformatics analysis of metabolites and metabolic pathways with significant ...


Glioma Grading Using Structural Magnetic Resonance Imaging And Molecular Data, Syed M.S. Reza, Manar D. Samad, Zeina A. Shboul, Karra A. Jones, Khan M. Iftekharuddin Jan 2019

Glioma Grading Using Structural Magnetic Resonance Imaging And Molecular Data, Syed M.S. Reza, Manar D. Samad, Zeina A. Shboul, Karra A. Jones, Khan M. Iftekharuddin

Electrical & Computer Engineering Faculty Publications

A glioma grading method using conventional structural magnetic resonance image (MRI) and molecular data from patients is proposed. The noninvasive grading of glioma tumors is obtained using multiple radiomic texture features including dynamic texture analysis, multifractal detrended fluctuation analysis, and multiresolution fractal Brownian motion in structural MRI. The proposed method is evaluated using two multicenter MRI datasets: (1) the brain tumor segmentation (BRATS-2017) challenge for high-grade versus low-grade (LG) and (2) the cancer imaging archive (TCIA) repository for glioblastoma (GBM) versus LG glioma grading. The grading performance using MRI is compared with that of digital pathology (DP) images in the ...


Il-12 Gene Electrotransfer Triggers A Change In Immune Response Within Mouse Tumors, Guilan Shi, Chelsea Edelblute, Sezgi Arpag, Cathryn Lundberg, Richard Heller Dec 2018

Il-12 Gene Electrotransfer Triggers A Change In Immune Response Within Mouse Tumors, Guilan Shi, Chelsea Edelblute, Sezgi Arpag, Cathryn Lundberg, Richard Heller

Bioelectrics Publications

Metastatic melanoma is an aggressive skin cancer with a relatively low survival rate. Immune-based therapies have shown promise in the treatment of melanoma, but overall complete response rates are still low. Previous studies have demonstrated the potential of plasmid IL-12 (pIL-12) delivered by gene electrotransfer (GET) to be an effective immunotherapy for melanoma. However, events occurring in the tumor microenvironment following delivery have not been delineated. Therefore, utilizing a B16F10 mouse melanoma model, we evaluated changes in the tumor microenvironment following delivery of pIL-12 using different GET parameters or injection of plasmid alone. The results revealed a unique immune cell ...


Pneumatospinning Of Collagen Microfibers From Benign Solvents, Seth Polk, Nardos Sori, Nick Thayer, Yas Maghdouri-White, Anna A. Bulysheva, Michael P. Francis Oct 2018

Pneumatospinning Of Collagen Microfibers From Benign Solvents, Seth Polk, Nardos Sori, Nick Thayer, Yas Maghdouri-White, Anna A. Bulysheva, Michael P. Francis

Medical Diagnostics & Translational Sciences Faculty Publications

Introduction. Current collagen fiber manufacturing methods for biomedical applications, such as electrospinning and extrusion, have had limited success in clinical translation, partially due to scalability, cost, and complexity challenges. Here we explore an alternative, simplified and scalable collagen fiber formation method, termed 'pneumatospinning,' to generate submicron collagen fibers from benign solvents. Methods and results. Clinical grade type I atelocollagen from calf corium was electrospun or pneumatospun as sheets of aligned and isotropic fibrous scaffolds. Following crosslinking with genipin, the collagen scaffolds were stable in media for over a month. Pneumatospun collagen samples were characterized using Fourier-transform infrared spectroscopy, circular dichroism ...


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 ...


Voltage Effects On Muscarinic Acetylcholine Receptor-Mediated Contractions Of Airway Smooth Muscle, Iurii Semenov, Robert Brenner Sep 2018

Voltage Effects On Muscarinic Acetylcholine Receptor-Mediated Contractions Of Airway Smooth Muscle, Iurii Semenov, Robert Brenner

Bioelectrics Publications

Studies have shown that the activity of muscarinic receptors and their affinity to agonists are sensitive to membrane potential. It was reported that in airway smooth muscle (ASM) depolarization evoked by high K+ solution increases contractility through direct effects on M3 muscarinic receptors. In this study, we assessed the physiological relevance of voltage sensitivity of muscarinic receptors on ASM contractility. Our findings reveal that depolarization by high K+ solution induces contraction in intact mouse trachea predominantly through activation of acetylcholine release from embedded nerves, and to a lesser extent by direct effects on M3 receptors. We therefore devised a pharmacological ...


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 ...


Antimicrobial Efficacy And Safety Of A Novel Gas Plasma-Activated Catheter Lock Solution, Sudhir Bhatt, Poonam Mehta, Chen Chen, Dayle A. Daines, Leonard A. Mermel, Hai-Lan Chen, Michael G. Kong Aug 2018

Antimicrobial Efficacy And Safety Of A Novel Gas Plasma-Activated Catheter Lock Solution, Sudhir Bhatt, Poonam Mehta, Chen Chen, Dayle A. Daines, Leonard A. Mermel, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

Antimicrobial lock solutions are important for prevention of microbial colonization and infection of long-term central venous catheters. We investigated the efficacy and safety of a novel antibiotic-free lock solution formed from gas plasma-activated disinfectant (PAD). Using a luminal biofilm model, viable cells of methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans in mature biofilms were reduced by 6 to 8 orders of magnitude with a PAD lock for 60 min. Subsequent 24-h incubation of PAD-treated samples resulted in no detectable regrowth of viable bacteria or fungi. As a comparison, the use of a minocycline-EDTA-ethanol lock solution for 60 ...


A Stepwise Compression-Relaxation Testing Method For Tissue Characterization And Tumor Detection Via A Two-Dimensional Tactile Sensor, Yichao Yang Jul 2018

A Stepwise Compression-Relaxation Testing Method For Tissue Characterization And Tumor Detection Via A Two-Dimensional Tactile Sensor, Yichao Yang

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation presents a stepwise compression-relaxation (SCR) testing method built upon a two-dimensional (2D) tactile sensor for mechanical characterization of soft tissues and tumor detection. The core of the 2D sensor entails one whole polydimethylsiloxane (PDMS) microstructure embedded with a 3×3 sensing-plate/transducer array. A soft sample was compressed by the 2D sensor with a step incremental depth at a ramp speed, and then relaxed for certain hold time. When a soft sample was compressed by the 2D sensor, the sensing-plates translated the sample response at different tissue sites to the sensor deflections, which were registered as resistance changes ...


Epithelial Sheet Response To External Stimuli, Yashar Bashirzadeh Jul 2018

Epithelial Sheet Response To External Stimuli, Yashar Bashirzadeh

Mechanical & Aerospace Engineering Theses & Dissertations

Mechanical communication of adherent cells with their micro-environment is mediated by cytoskeletal and adhesion proteins. These mechanical links aid tissues in maintaining their coherence in the context of the surrounding extra cellular matrix (ECM). Epithelial tissues exert force on the ECM through integrin-based junctions and maintain their coherency through E-cadherin-based cell-cell junctions while dynamically undergoing collective migration. Such a complex network of communication involving the cell cytoskeleton and adhesion proteins modulates the tissue's response to external cues. Two distinct forms of such external stimuli are those of electrical and mechanical origin.

Epithelial tissues quickly respond to physiologically relevant electric ...


Developmental Steps For A Functional Three-Dimensional Cell Culture System For The Study Of Asymmetrical Division Of Neural Stem Cells, Martina Zamponi Jul 2018

Developmental Steps For A Functional Three-Dimensional Cell Culture System For The Study Of Asymmetrical Division Of Neural Stem Cells, Martina Zamponi

Biomedical Engineering Theses & Dissertations

Stem cells are a cell type present during and following development, which possess self- renewal properties, as well as the ability to differentiate into specific cells. Asymmetrical division is the cellular process that allows stem cells to produce one differentiated and one un-differentiated daughter cell during the same mitotic event. Insights in the molecular mechanisms of such process are minimal, due to the absence of effective methods for its targeted study. Currently, traditional methods of investigation include monolayer cell culture and animal models. The first poses structural limitations to the accurate representation of human tissue and cell structures, while animal ...


Tracing Actin Filament Bundles In Three-Dimensional Electron Tomography Density Maps Of Hair Cell Stereocilia, Salim Sazzed, Junha Song, Julio Kovacs, Willi Wriggers, Manfred Auer, Jing He Apr 2018

Tracing Actin Filament Bundles In Three-Dimensional Electron Tomography Density Maps Of Hair Cell Stereocilia, Salim Sazzed, Junha Song, Julio Kovacs, Willi Wriggers, Manfred Auer, Jing He

Computer Science Faculty Publications

Cryo-electron tomography (cryo-ET) is a powerful method of visualizing the three-dimensional organization of supramolecular complexes, such as the cytoskeleton, in their native cell and tissue contexts. Due to its minimal electron dose and reconstruction artifacts arising from the missing wedge during data collection, cryo-ET typically results in noisy density maps that display anisotropic XY versus Z resolution. Molecular crowding further exacerbates the challenge of automatically detecting supramolecular complexes, such as the actin bundle in hair cell stereocilia. Stereocilia are pivotal to the mechanoelectrical transduction process in inner ear sensory epithelial hair cells. Given the complexity and dense arrangement of actin ...


Understanding The Mechanical Behavior Of Costal Cartilage At Their Curved Exterior Surface Via A Tactile Sensor With A Built-In Probe For Distributed-Deflection Detection, Jiayue Shen Apr 2018

Understanding The Mechanical Behavior Of Costal Cartilage At Their Curved Exterior Surface Via A Tactile Sensor With A Built-In Probe For Distributed-Deflection Detection, Jiayue Shen

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation is aimed to determine the mechanical properties at the exterior surface of costal cartilages (CC) and examine how they vary with the cartilage length and the anatomical sites of CC in the ribcage via conformal indentation testing which is built upon a tactile sensor for distributed-deflection detection. The sensor entails a rectangular Polydimethylsiloxane (PDMS) microstructure sensing-plate integrated with a 5 ×1 transducer array with 0.75mm spatial resolution underneath and a built-in probe of 0.5mm×5mm×3mm above. By pressing the sensor against the exterior surface of a CC tissue with a pre-defined indentation pattern, the sensor ...


Study Of Abc Membrane Transporters In Single Live Cells, Preeyaporn Songkiatisak Apr 2018

Study Of Abc Membrane Transporters In Single Live Cells, Preeyaporn Songkiatisak

Chemistry & Biochemistry Theses & Dissertations

The multidrug ATP-binding cassette (ABC) membrane transporters (efflux pumps) are found in both prokaryotes and eukaryotes and they can extrude diverse structurally unrelated substrates, such as antibiotics and chemotherapeutic agents out of the cells. The efflux pumps are responsible for multidrug resistance (MDR) and the failure of numerous treatments in infections and cancers. All ABC membrane transporters share a common modular topology containing two transmembrane domains (TMDs) and two nucleotide binding domains (NBDs). The underlying molecular mechanisms regarding how the similar structural ABC membrane transporters could selectively extrude a wide variety of substrates and cause MDR, are not yet fully ...


Non-Invasive Picosecond Pulse System For Electrostimulation, Ross Aaron Petrella Apr 2018

Non-Invasive Picosecond Pulse System For Electrostimulation, Ross Aaron Petrella

Electrical & Computer Engineering Theses & Disssertations

Picosecond pulsed electric fields have been shown to have stimulatory effects, such as calcium influx, activation of action potential, and membrane depolarization, on biological cells. Because the pulse duration is so short, it has been hypothesized that the pulses permeate a cell and can directly affect intracellular cell structures by bypassing the shielding of the membrane. This provides an opportunity for studying new biophysics. Furthermore, radiating picosecond pulses can be efficiently done by a compact antenna because the antenna size is comparable to the pulse width. However, all of the previous bioelectric studies regarding picosecond pulses have been conducted in ...


3d Bioprinting Systems For The Study Of Mammary Development And Tumorigenesis, John Reid Apr 2018

3d Bioprinting Systems For The Study Of Mammary Development And Tumorigenesis, John Reid

Electrical & Computer Engineering Theses & Disssertations

Understanding the microenvironmental factors that control cell function, differentiation, and stem cell renewal represent the forefront of developmental and cancer biology. To accurately recreate and model these dynamic interactions in vitro requires both precision-controlled deposition of multiple cell types and well-defined three-dimensional (3D) extracellular matrix (ECM). To achieve this goal, we hypothesized that accessible bioprinting technology would eliminate the experimental inconsistency and random cell-organoid formation associated with manual cell-matrix embedding techniques commonly used for 3D, in vitro cell cultures. The first objective of this study was to adapt a commercially-available, 3D printer into a 3D bioprinter. Goal-based computer simulations were ...


Wild-Type P53 Enhances Endothelial Barrier Function By Mediating Rac1 Signalling And Rhoa Inhibition, Nektarios Barabutis, Christiana Dimitropoulou, Betsy Gregory, John D. Catravas Jan 2018

Wild-Type P53 Enhances Endothelial Barrier Function By Mediating Rac1 Signalling And Rhoa Inhibition, Nektarios Barabutis, Christiana Dimitropoulou, Betsy Gregory, John D. Catravas

Bioelectrics Publications

Inflammation is the major cause of endothelial barrier hyper-permeability, associated with acute lung injury and acute respiratory distress syndrome. This study reports that p53 "orchestrates" the defence of vascular endothelium against LPS, by mediating the opposing actions of Rac1 and RhoA in pulmonary tissues. Human lung microvascular endothelial cells treated with HSP90 inhibitors activated both Rac1- and P21-activated kinase, which is an essential element of vascular barrier function. 17AAG increased the phosphorylation of both LIMK and cofilin, in contrast to LPS which counteracted those effects. Mouse lung microvascular endothelial cells exposed to LPS exhibited decreased expression of phospho-cofilin. 17AAG treatment ...


Targeting Ovarian Cancer And Endothelium With An Allosteric Ptp4a3 Phosphatase Inhibitor, Kelley E. Mcqueeney, Joseph M. Salamoun, James C. Burnett, Nektarios Barabutis, Paula Pekic, Sophie L. Lewandowski, Danielle C. Llaneza, Robert Cornelison, Yunpeng Bai, Zhong-Yin Zhang, John D. Catravas Jan 2018

Targeting Ovarian Cancer And Endothelium With An Allosteric Ptp4a3 Phosphatase Inhibitor, Kelley E. Mcqueeney, Joseph M. Salamoun, James C. Burnett, Nektarios Barabutis, Paula Pekic, Sophie L. Lewandowski, Danielle C. Llaneza, Robert Cornelison, Yunpeng Bai, Zhong-Yin Zhang, John D. Catravas

Bioelectrics Publications

Overexpression of protein tyrosine phosphatase PTP4A oncoproteins is common in many human cancers and is associated with poor patient prognosis and survival. We observed elevated levels of PTP4A3 phosphatase in 79% of human ovarian tumor samples, with significant overexpression in tumor endothelium and pericytes. Furthermore, PTP4A phosphatases appear to regulate several key malignant processes, such as invasion, migration, and angiogenesis, suggesting a pivotal regulatory role in cancer and endothelial signaling pathways. While phosphatases are attractive therapeutic targets, they have been poorly investigated because of a lack of potent and selective chemical probes. In this study, we disclose that a potent ...


Nano-Pulse Stimulation Ablates Orthotopic Rat Hepatocellular Carcinoma And Induces Innate And Adaptive Memory Immune Mechanisms That Prevent Recurrence, Brittany P. Lassiter, Siqi Guo, Stephen J. Beebe Jan 2018

Nano-Pulse Stimulation Ablates Orthotopic Rat Hepatocellular Carcinoma And Induces Innate And Adaptive Memory Immune Mechanisms That Prevent Recurrence, Brittany P. Lassiter, Siqi Guo, Stephen J. Beebe

Bioelectrics Publications

Nano-pulse stimulation (NPS), previously called nsPEFs, induced a vaccine-like effect after ablation of orthotopic N1-S1 hepatocellular carcinoma (HCC), protecting rats from subsequent challenges with N1-S1 cells. To determine immunity, immune cell phenotypes were analyzed in naïve, treated and protected rats. NPS provides a positive, post-ablation immuno-therapeutic outcome by alleviating immunosuppressive T regulatory cells (Treg) in the tumor microenvironment (TME), allowing dendritic cell influx and inducing dynamic changes in natural killer cells (NKs), NKT-cells and T-lymphocytes in blood, spleen and liver. NPS induced specific increases in NKs and NKT-cells expressing CD8 and activation receptors CD314-NKG2D and CD161 (NK1.1) in the ...


Transport Of Charged Small Molecules After Electropermeabilization - Drift And Diffusion, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier Jan 2018

Transport Of Charged Small Molecules After Electropermeabilization - Drift And Diffusion, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier

Bioelectrics Publications

Background: Applications of electric-field-induced permeabilization of cells range from cancer therapy to wastewater treatment. A unified understanding of the underlying mechanisms of membrane electropermeabilization, however, has not been achieved. Protocols are empirical, and models are descriptive rather than predictive, which hampers the optimization and expansion of electroporation-based technologies. A common feature of existing models is the assumption that the permeabilized membrane is passive, and that transport through it is entirely diffusive. To demonstrate the necessity to go beyond that assumption, we present here a quantitative analysis of the post-permeabilization transport of three small molecules commonly used in electroporation research-YO-PRO-1, propidium ...


Asymmetric Patterns Of Small Molecule Transport After Nanosecond And Microsecond Electropermeabilization, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier Jan 2018

Asymmetric Patterns Of Small Molecule Transport After Nanosecond And Microsecond Electropermeabilization, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier

Bioelectrics Publications

Imaging of fluorescent small molecule transport into electropermeabilized cells reveals polarized patterns of entry, which must reflect in some way the mechanisms of the migration of these molecules across the compromised membrane barrier. In some reports, transport occurs primarily across the areas of the membrane nearest the positive electrode (anode), but in others cathode-facing entry dominates. Here we compare YO-PRO-1, propidium, and calcein uptake into U-937 cells after nanosecond (6 ns) and microsecond (220 µs) electric pulse exposures. Each of the three dyes exhibits a different pattern. Calcein shows no preference for anode- or cathode-facing entry that is detectable with ...


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 ...


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 ...


Effects Of Protein-Coated Nanofibers On Conformation Of Gingival Fibroblast Spheroids: Potential Utility For Connective Tissue Regeneration, Gili Kaufman, Ryan A. Whitescarver, Laiz Nunes, Xavier-Lewis Palmer, Drago Skrtic, Wojtek Tutak Jan 2018

Effects Of Protein-Coated Nanofibers On Conformation Of Gingival Fibroblast Spheroids: Potential Utility For Connective Tissue Regeneration, Gili Kaufman, Ryan A. Whitescarver, Laiz Nunes, Xavier-Lewis Palmer, Drago Skrtic, Wojtek Tutak

Engineering Technology Faculty Publications

Deep wounds in the gingiva caused bytrauma or surgery require a rapid and robust healing of connective tissues. Wepropose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels ofspecific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature ofdense and soft connective tissues. Gingival fibroblast monolayers and3D spheroids were cultured onECMsubstrate and covered with gas-blown poly-(DL-lactide-co-glycolide)(PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed byF-actin staining and confocal ...


Alteration Of Metabolite Profiling By Cold Atmospheric Plasma Treatment In Human Myeloma Cells, Dehui Xu, Yujing Xu, Ning Ning, Qingjie Cui, Zhijie Liu, Xiaohua Wang, Dingxin Liu, Hailan Chen, Michael G. Kong Jan 2018

Alteration Of Metabolite Profiling By Cold Atmospheric Plasma Treatment In Human Myeloma Cells, Dehui Xu, Yujing Xu, Ning Ning, Qingjie Cui, Zhijie Liu, Xiaohua Wang, Dingxin Liu, Hailan Chen, Michael G. Kong

Bioelectrics Publications

BACKGROUND: Despite new progress of chemotherapy in multiple myeloma (MM) clinical treatment, MM is still a refractory disease and new technology is needed to improve the outcomes and prolong the survival. Cold atmospheric plasma is a rapidly developed technology in recent years, which has been widely applied in biomedicine. Although plasma could efficiently inactivate various tumor cells, the effects of plasma on tumor cell metabolism have not been studied yet.

METHODS: In this study, we investigated the metabolite profiling of He plasma treatment on myeloma tumor cells by gas-chromatography time-of-flight (GC-TOF) mass-spectrometry. Meanwhile, by bioinformatic analysis such as GO and ...