Bioelectrical and Neuroengineering Commons^™

A New Pulsed Electric Field Therapy For Melanoma Disrupts The Tumor's Blood Supply And Causes Complete Remission Without Recurrence, Richard Nuccitelli, Xinhua Chen, Andrei G. Pakhomov, Wallace H. Baldwin, Saleh Sheikh, Jennifer L. Pomicter, Wei Ren, Chris Osgood, R. James Swanson, Juergen F. Kolb, Stephen J. Beebe, Karl H. Schoenbach

Bioelectrics Publications

We have discovered a new, ultrafast therapy for treating skin cancer that is extremely effective with a total electric field exposure time of only 180 mu sec. The application of 300 high-voltage (40 kV/cm), ultrashort (300 nsec) electrical pulses to murine melanomas in vivo triggers both necrosis and apoptosis, resulting in complete tumor remission within an average of 47 days in the 17 animals treated. None of these melanomas recurred during a 4-month period after the initial melanoma had disappeared. These pulses generate small, long-lasting, rectifying nanopores in the plasma membrane of exposed cells, resulting in increased membrane permeability to …

Comparison Of Electrically Mediated And Liposome-Complexed Plasmid Dna Delivery To The Skin, Loree C. Heller, Mark J. Jaroszeski, Domenico Coppola, Richard Heller

Bioelectrics Publications

BACKGROUND: Electroporation is an established technique for enhancing plasmid delivery to many tissues in vivo, including the skin. We have previously demonstrated efficient delivery of plasmid DNA to the skin utilizing a custom-built four-plate electrode. The experiments described here further evaluate cutaneous plasmid delivery using in vivo electroporation. Plasmid expression levels are compared to those after liposome mediated delivery.

METHODS: Enhanced electrically-mediated delivery, and less extensively, liposome complexed delivery, of a plasmid encoding the reporter luciferase was tested in rodent skin. Expression kinetics and tissue damage were explored as well as testing in a second rodent model.

RESULTS: Experiments …

Stochastic Calculations For Computation Of Radiation Effects And Cell Survivability Under Voltage Pulsing, Madhuri Ganapathiraju

Electrical & Computer Engineering Theses & Dissertations

Statistical computations are an important tool for the analysis of stochastic phenomena and processes that are characterized by variability. Biological systems (e.g., cells, tissues etc.) are perfect examples wherein response to a given external stimulus can be varied and needs to be adequately considered. The Monte Carlo method of analysis has now been recognized as the most effective way of treating stochastic variability.

This thesis uses Monte Carlo based simulations to probe two problems that require the quantification and modeling of effects caused by energy deposition onto biological matter from external sources. One problem involves the probabilistic study of the …

Microfabrication Of An Optical Chamber For Exposing Living Cells To Pulsed Electric Fields, Saleh Sheikh

Electrical & Computer Engineering Theses & Dissertations

I have fabricated a chamber which enables the application of Nanosecond Pulsed Electric Fields (nsPEFs) to living cells while monitoring their real time fluorescence with an inverted microscope. The No. I thickness (150µm nominal) coverslip glass substrate used for fabrication allows the use of high numerical aperture oil immersion objectives for imaging intracellular organelles. Electrodes are fabricated by first evaporating a chromium adhesion layer, followed by a nickel seed layer. Subsequently, an ultra-thick positive photoresist is applied and patterned to create a 30µm thick electroplating mold. The electrodes are then electrodeposited into the mold from a nickel sulfamate plating bath. …

Simulations Of Intracellular Calcium Release In Response To High-Intensity, Ultrashort Electric Pulse, Anh Nguyen

Electrical & Computer Engineering Theses & Dissertations

Calcium modulation is an important signaling process and could even contribute to cell apoptosis through ionic-induced perturbations in trans-membrane potential at the mitochondria. In this research, the numerical study constitutes a first step in quantitatively probing the time- and spatially-dependent modulation of calcium dynamics through the application of external electrical fields. The research uses both widely accepted deterministic continuum and discrete stochastic intracellular calcium models coupling with external electric field, with a focus on high-intensity ultrashort pulse electrical field.

For deterministic continuum intracellular calcium models with electric field assisted, numerical simulations for electrically induced, intra-cellular calcium-release from the endoplasmic reticulum …

Molecular Dynamics Simulations To Probe Effects Of Ultra-Short, Very-High Voltage Pulses On Cells, Viswanadham Sridhara

Electrical & Computer Engineering Theses & Dissertations

The use of very high electric fields (∼ 100kV/cm or higher) with pulse durations in the nanosecond range (Ultra-short) has been a very recent development in bioelectrics. Traditionally, the electric field effects have mostly been confined to: (a) low field, long-duration pulses, and (b) focused mainly on electroporation studies. Thus, aspects such as possible field-induced DNA damage, calcium release, alterations in neuro-transmitters, or voltage-gating have generally been overlooked.

Ultra-short, high-field pulses open the way to targeted and deliberate apoptotic cell killing (e.g., of tumor cells). Though experimental data is very useful, it usually yields information on macroscopic variables that is …

Simulation And Modeling Of Nerve Impulse Propagation And Its Blockage By External Electrical Stimulation, Nidhi Nahar

Electrical & Computer Engineering Theses & Dissertations

The electric nature of biological tissues permits the transmission of signals for information and for control and is, therefore, of vital importance for life. The latest scientific achievements and nanoscale probing techniques now allow scientists to research at the subcellular level by measuring the electric current flows through a single ion channel of the cell membrane with the patch-clamp method. With the latter approach, the effects of electrical stimulation can be quantified, understood, and applied to molecular biology and the development of medical diagnostic and therapeutic methods.

In this thesis, the Hodgkin-Huxley approach for unmyelinated fibers, coupled with a transmission …

The Effects Of Ultrashort Pulsed Electric Fields On The Fluorescent Molecule Bodipy Fl C5 Ceramide, Rachael Sara Shevin

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric fields are able to manipulate internal cell organelles by taking advantage of the small but finite time required for charge to establish across a capacitive barrier. Pulsed electric fields also affect macromolecular structures such as enzymes and proteins. Application of a single nanosecond pulsed electric field decreases the fluorescence of a commercially available biological dye Bodipy FL C₅ Ceramide, used to observe the Golgi apparatus of living cells. The effect is seen when the fluorophore is exposed to an electric field both in vitro and when incorporated into the Golgi of a living Jurkat cell. Observation …

Temporal Calcium Response Of Jurkat Cells To Nanosecond Pulsed Electric Fields, Shaka Shakar Scarlett

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric fields (nsPEF) of megavolt per meter field strengths can interact with subcellular structures [1] and consequently trigger a variety of biological events. The exposure can induce apoptosis, as well as an array of differential "sub-lethal effects." One of the most sensitive and immediate responses is the increase in intracellular calcium concentration in pulsed cells [2], [3][4].We investigated the response of Jurkat cells (a human leukemic cell line) to nsPEFs of 60 ns duration and field strengths from 25 tol00 kV/cm. The development of the induced calcium response in individual cells was studied by spinning-disc confocal microscopy with …

Biological System Impedance Identification Using Stochastic Estimation And Control, Enrique Mendezaceves

Theses and Dissertations

In an effort to find a less invasive way of testing for different cell abnormalities and finding more practical tests for different cellular mutations, this project makes use of a well-known technique called cellular impedance spectroscopy coupled with stochastic estimation. Impedance spectroscopy, the measurement of the complex resistance of a biological body, is not a new technology; it has been around for many years and has been used to make electrical representations of different biological systems. The problem with this procedure is that models cannot be used for system identification. Stochastic estimation can complement a model produced by analyzing the …

Brownian Dynamics Simulation Studies Of Ion Throughput During Cellular Electroporation, Juan A. Gonzalez-Cuevas

Electrical & Computer Engineering Theses & Dissertations

The purpose of the present research work is to analyze the flow of ions through pores formed in the plasma membrane of biological cells during electroporation. In this regard, simulations have been conducted to track the movement of ions in 3-D space based on a Brownian dynamics model, which is mostly deterministic but has some stochastic properties to account for ionic scattering. From the Brownian dynamics simulations, it has been possible to estimate the pore's conductance as well as transport parameters such as the diffusion coefficient and mobility within the pore region, of which there is no experimental data currently …

Time Domain Dielectric Spectroscopy Analysis Of Hl-60 Cell Suspensions After Microsecond And Submicrosecond Pulsed Electric Fields, Allen Laurence Garner

Electrical & Computer Engineering Theses & Dissertations

Pulsed electric fields (PEF's) above a certain voltage threshold cause electroporation for microsecond pulses and intracellular effects for submicrosecond pulses. Models describing these effects often depend on the electrical properties of the cell, which are altered by the PEF. Time domain dielectric spectroscopy was used to provide data for these models and to measure changes in the conductivity of HL-60 cell suspensions due to single 50 μs and 10 ns PEF's of the same energy. For 1.1 kV/cm, 50 μs pulses, the conductivity rose within a minute after the pulse and dropped dramatically approximately forty minutes after the pulse. For …

Simulation Studies Of Cellular Electroporation Due To Ultra-Fast Electric Pulses, Gayathri R. Barthaki

Electrical & Computer Engineering Theses & Dissertations

Biological systems, from cells to ecosystems, are intrinsically complex information-processing networks. It often becomes difficult to predict their behavior during an experimental investigation, as their behavior is fundamentally chaotic, Hence, building models that mimic the dynamics of such systems and performing computer simulations would help in understanding, predicting, controlling and optimizing these systems. This thesis is aimed at the development of a mathematical model for the process of electroporation in biological cells when they are subjected to ultra-fast electric pulses and at conducting simulations to understand its dynamic behavior with special emphasis on the physics of ultra-short time scales.

With …

Aneuploidy Frequencies In Semen Fractions From Ten Oligoasthenoteratozoospermic Patients Donating Sperm For Intracytoplasmic Sperm Injection, Jerome Pfeffer, Myung-Geol Pang, Stanton F. Hoegerman, Christopher J. Osgood, M. W. Stacey, Jacob Mayer, Sergio Oehninger, William G. Kearns

Biological Sciences Faculty Publications

Objective: To determine aneuploidy frequencies in pellet and swim-up semen fractions from 10 infertile men with severe oligoasthenoteratozoospermia (OAT) who were donating sperm for intracytoplasmic sperm injection and to determine whether the swim-up isolation method would successfully separate aneuploid from haploid sperm.

Design: Prospective study.

Setting: Infertility clinic and molecular genetics laboratory.

Patient(s): Ten patients with severe OAT.

Intervention(s): Cytogenetic analyses by fluorescence in situ hybridization to determine aneuploidy frequencies for chromosomes 1, 13, 18, 21, X, and Y in sperm from swim-up and pellet fractions.

Main Outcome Measure(s): Gametic aneuploidy was scored in sperm fractions separated by the swim-up …

The Afit Multielectrode Array For Neural Recording And Simulation: Design, Testing, And Encapsulation, James R. Reid Jr

Theses and Dissertations

A two-dimensional, X-Y addressable, multiplexed array of 256 electrodes (16 x 16) has been fabricated using conventional semiconductor processing techniques. The individual electrodes are 16O microns x 160 microns, approximating the size of the cortical columns; the overall array size is 3910 microns x 3910 microns. The array has been fitted to a chronically implantable package and tested for several days in a simulated neural environment. EEG-like data were collected successfully from individual electrodes in the array. This array improves on a previous design of a 16 electrode (4 x 4) array that was chronically implanted on the cortex of …

A Topographical Analysis Of The Human Electroencephalogram For Patterns In The Development Of Motion Sickness, George S. Vogen

Theses and Dissertations

A topographical analysis was performed on 12 electroencephalograms (EEGs) collected from 10 volunteers who experienced motion sickness through cross-coupled Coriolis stimulation. Seven males and three females participated in the research conducted at the Air Force Institute of Technology, Wright- Patterson AFB. Two male volunteers participated in double-blind placebo/ phenytoin trials. Static brain maps and dynamic EEGs which focused on delta (below 3Hz) activity during the development of motion sickness revealed a seizure-like propagation pattern. With initial symptoms, a clear left parietal focus was seen in all records. A less dominant left fronto-temporal focus was present in 11 of the 12 …