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Articles 31 - 60 of 102

Full-Text Articles in Bioelectrical and Neuroengineering

Blood–Brain Barrier Breakdown And Astrocyte Reactivity Evident In The Absence Of Behavioral Changes After Repeated Traumatic Brain Injury, Celeste Dunn, Nasya Sturdivant, Sara Venier, Syed Ali, Jeffery Wolchok, Kartik Balachandran Aug 2021

Blood–Brain Barrier Breakdown And Astrocyte Reactivity Evident In The Absence Of Behavioral Changes After Repeated Traumatic Brain Injury, Celeste Dunn, Nasya Sturdivant, Sara Venier, Syed Ali, Jeffery Wolchok, Kartik Balachandran

Biomedical Engineering Faculty Publications and Presentations

Repeated traumatic brain injuries (TBIs) cause debilitating effects. Without understanding the acute effects of repeated TBIs, treatment options to halt further degeneration and damage cannot be developed. This study sought to examine the acute effects of blood–brain barrier (BBB) dysfunction, edema, inflammation and behavioral changes after either a single or double TBI using a C57BL/6 mouse model. We examined the effects of one or two TBIs, of either a mild or moderate severity. Double injuries were spaced 7 days apart, and all analysis was performed 24 h post-injury. To examine edema and inflammation, protein levels of glial fibrillary acidic protein …


Acute Effect Of High‑Definition And Conventional Tdcs On Exercise Performance And Psychophysiological Responses In Endurance Athletes: A Randomized Controlled Trial, Daniel Gomes Da Silva Machado, Marom Bikson, Abhishek Datta, Egas Caparelli‑Dáquer, Gozde Unal, Abrahão F. Baptista, Edilson Serpeloni Cyrino, Li Min Li, Edgard Morya, Alexandre Moreira, Alexandre Hideki Okano Jul 2021

Acute Effect Of High‑Definition And Conventional Tdcs On Exercise Performance And Psychophysiological Responses In Endurance Athletes: A Randomized Controlled Trial, Daniel Gomes Da Silva Machado, Marom Bikson, Abhishek Datta, Egas Caparelli‑Dáquer, Gozde Unal, Abrahão F. Baptista, Edilson Serpeloni Cyrino, Li Min Li, Edgard Morya, Alexandre Moreira, Alexandre Hideki Okano

Publications and Research

Transcranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called “conventional” tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg− 1 min− …


The Impact Of Nanopulse Treatment On The Tumor Microenvironment In Breast Cancer: Overturning The Treg Immunosuppressive Dominance, Anthony Nanajian Jul 2021

The Impact Of Nanopulse Treatment On The Tumor Microenvironment In Breast Cancer: Overturning The Treg Immunosuppressive Dominance, Anthony Nanajian

Biomedical Sciences Theses & Dissertations

Nanopulse treatment (NPT) is a high-power electric engineering modality that has been shown to be an effective local tumor treatment approach in multiple cancer models. Our previous studies on the orthotopic 4T1-luc breast cancer model demonstrated that NPT ablated local tumors. The treatment consequently conferred protection against a second live tumor challenge and minimized spontaneous metastasis. This study aims to understand how NPT mounts a potent immune response in a predominantly immunosuppressive tumor.

NPT changed the local and systemic dynamics of immunosuppressive cells by significantly reducing the numbers of regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages …


Somatic Inhibition By Microscopic Magnetic Stimulation, Hui Ye Jun 2021

Somatic Inhibition By Microscopic Magnetic Stimulation, Hui Ye

Biology: Faculty Publications and Other Works

Electric currents can produce quick, reversible control of neural activity. Externally applied electric currents have been used in inhibiting certain ganglion cells in clinical practices. Via electromagnetic induction, a miniature-sized magnetic coil could provide focal stimulation to the ganglion neurons. Here we report that high-frequency stimulation with the miniature coil could reversibly block ganglion cell activity in marine mollusk Aplysia californica, regardless the firing frequency of the neurons, or concentration of potassium ions around the ganglion neurons. Presence of the ganglion sheath has minimal impact on the inhibitory effects of the coil. The inhibitory effect was local to the …


Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler Jan 2021

Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler

Bioelectrics Publications

The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious …


Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano Jan 2021

Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano

Bioelectrics Publications

In this study, we used B16-F10 cells grown in the dorsal skinfold chamber (DSC) preparation that allowed us to gain optical access to the processes triggered by photodynamic therapy (PDT). Partial irradiation of a photosensitized melanoma triggered cell death in non-irradiated tumor cells. Multiphoton intravital microscopy with genetically encoded fluorescence indicators revealed that bystander cell death was mediated by paracrine signaling due to adenosine triphosphate (ATP) release from connexin (Cx) hemichannels (HCs). Intercellular calcium (Ca2+) waves propagated from irradiated to bystander cells promoting intracellular Ca2+ transfer from the endoplasmic reticulum (ER) to mitochondria and rapid activation of …


The Role Of Reactive Oxygen Species In The Immunity Induced By Nano-Pulse Stimulation, Siqi Guo, Niculina I. Burcus, Megan Scott, Yu Jing, Iurii Semenov Jan 2021

The Role Of Reactive Oxygen Species In The Immunity Induced By Nano-Pulse Stimulation, Siqi Guo, Niculina I. Burcus, Megan Scott, Yu Jing, Iurii Semenov

Bioelectrics Publications

Reactive oxygen species (ROS) are byproducts of tumor cells treated with Nano-Pulse Stimulation (NPS). Recently, ROS have been suggested as a contributing factor in immunogenic cell death and T cell-mediated immunity. This research further investigated the role of NPS induced ROS in antitumor immunity. ROS production in 4T1-luc breast cancer cells was characterized using three detection reagents, namely, Amplex Red, MitoSox Red, and Dihydroethidium. The efficiency of ROS quenching was evaluated in the presence or absence of ROS scavengers and/or antioxidants. The immunogenicity of NPS treated tumor cells was assessed by ex vivo dendritic cell activation, in vivo vaccination assay …


Photodynamic Therapy Of Inorganic Complexes For The Treatment Of Cancer, Chloe B. Smith, Lindsay C. Days, Duaa R. Alajroush, Khadija Faye, Yara Khodour, Stephen J. Beebe, Alvin Holder Jan 2021

Photodynamic Therapy Of Inorganic Complexes For The Treatment Of Cancer, Chloe B. Smith, Lindsay C. Days, Duaa R. Alajroush, Khadija Faye, Yara Khodour, Stephen J. Beebe, Alvin Holder

Chemistry & Biochemistry Faculty Publications

Photodynamic therapy (PDT) is a medicinal tool that uses a photosensitiser and a light source to treat several conditions, including cancer. PDT uses reactive oxygen species (ROS) such as cytotoxic singlet oxygen 1O2 to induce cell death in cancer cells. Chemotherapy has historically utilized the cytotoxic effects of many metals, especially transition-metal complexes. However, chemotherapy is a systemic treatment so all cells in a patient's body are exposed to the same cytotoxic effects. Transition metal complexes have also shown high cytotoxicity as PDT agents. PDT is a potential localized method for treating several cancer types by using inorganic …


Bio-Inspired Materials For Electrochemical Sensors, Matthew Joseph Hummel Jan 2021

Bio-Inspired Materials For Electrochemical Sensors, Matthew Joseph Hummel

Electronic Theses and Dissertations

Electrochemical biosensors are a rapidly growing research area that has greatly improved its specificity, accuracy, and precision in the detection of biomolecules in contemporary literature and industry alike. Typically, these systems exist in a three-electrode conformation with a working electrode functioning as the anode, a counter electrode functioning as the cathode, and a reference electrode allowing for the control of potential in the system. The method by which these sensors work is through the sharing of electrons via redox reactions with the target molecule and the working electrode or modifications on its surface. By exploiting the function of biomaterials that …


Evaluating Neuromuscular Function Of The Biceps Brachii After Spinal Cord Injury: Assessment Of Voluntary Activation And Motor Evoked Potential Input-Output Curves Using Transcranial Magnetic Stimulation, Thibault Roumengous Jan 2021

Evaluating Neuromuscular Function Of The Biceps Brachii After Spinal Cord Injury: Assessment Of Voluntary Activation And Motor Evoked Potential Input-Output Curves Using Transcranial Magnetic Stimulation, Thibault Roumengous

Theses and Dissertations

Activation of upper limb muscles is important for independent living after cervical spinal cord injury (SCI) that results in tetraplegia. An emerging, non-invasive approach to address post-SCI muscle weakness is modulation of the nervous system. A long-term goal is to develop neuromodulation techniques to reinnervate (i.e. resupply nerve to) muscle fiber and thereby increase muscle function in individuals with tetraplegia. Towards this goal, developing monitoring techniques to quantify neuromuscular function is needed to better direct neurorehabilitation. Assessment of voluntary activation (VA) is a promising approach because the location of the stimulus can be applied cortically using transcranial magnetic stimulation (TMS) …


Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand Jan 2021

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …


When The Brain Plays A Game: Neural Responses To Visual Dynamics During Naturalistic Visual Tasks, Jason Ki Jan 2021

When The Brain Plays A Game: Neural Responses To Visual Dynamics During Naturalistic Visual Tasks, Jason Ki

Dissertations and Theses

Many day-to-day tasks involve processing of complex visual information in a continuous stream. While much of our knowledge on visual processing has been established from reductionist approaches in lab-controlled settings, very little is known about the processing of complex dynamic stimuli experienced in everyday scenarios. Traditional investigations employ event-related paradigms that involve presentation of simple stimuli at select locations in visual space and discrete moments in time. In contrast, visual stimuli in real-life are highly dynamic, spatially-heterogeneous, and semantically rich. Moreover, traditional experiments impose unnatural task constraints (e.g., inhibited saccades), thus, it is unclear whether theories developed under the reductionist …


Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt Dec 2020

Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt

Publications and Research

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation approach in which low level currents are administered over the scalp to influence underlying brain function. Prevailing theories of tDCS focus on modulation of excitation-inhibition balance at the local stimulation location. However, network level effects are reported as well, and appear to depend upon differential underlying mechanisms. Here, we evaluated potential network-level effects of tDCS during the Serial Reaction Time Task (SRTT) using convergent EEG- and fMRI-based connectivity approaches. Motor learning manifested as a significant (p <.0001) shift from slow to fast responses and corresponded to a significant increase in beta-coherence (p <.0001) and fMRI connectivity (p <.01) particularly within the visual-motor pathway. Differential patterns of tDCS effect were observed within different parametric task versions, consistent with network models. Overall, these findings demonstrate objective physiological effects of tDCS at the network level that result in effective behavioral modulation when tDCS parameters are matched to network-level requirements of the underlying task.


Update On The Use Of Transcranial Electrical Brain Stimulation To Manage Acute And Chronic Covid-19 Symptoms, Giuseppina Pilloni, Marom Bikson, Bashar W. Badran, Mark S. George, Steven A. Kautz, Alexandre Hideki Okano, Abrahão Fontes Baptista, Leigh E. Charvet Nov 2020

Update On The Use Of Transcranial Electrical Brain Stimulation To Manage Acute And Chronic Covid-19 Symptoms, Giuseppina Pilloni, Marom Bikson, Bashar W. Badran, Mark S. George, Steven A. Kautz, Alexandre Hideki Okano, Abrahão Fontes Baptista, Leigh E. Charvet

Publications and Research

The coronavirus disease 19 (COVID-19) pandemic has resulted in the urgent need to develop and deploy treatment approaches that can minimize mortality and morbidity. As infection, resulting illness, and the often prolonged recovery period continue to be characterized, therapeutic roles for transcranial electrical stimulation (tES) have emerged as promising non-pharmacological interventions. tES techniques have established therapeutic potential for managing a range of conditions relevant to COVID-19 illness and recovery, and may further be relevant for the general management of increased mental health problems during this time. Furthermore, these tES techniques can be inexpensive, portable, and allow for trained self-administration. Here, …


Characterization Of Neuronal Differentiation And Activity In Human-Induced Pluripotent Neural Stem Cells, Allison Biddinger Aug 2020

Characterization Of Neuronal Differentiation And Activity In Human-Induced Pluripotent Neural Stem Cells, Allison Biddinger

The Journal of Purdue Undergraduate Research

No abstract provided.


Validation Of Nanosecond Pulse Cancellation Using A Quadrupole Exposure System, Hollie A. Ryan Aug 2020

Validation Of Nanosecond Pulse Cancellation Using A Quadrupole Exposure System, Hollie A. Ryan

Biomedical Engineering Theses & Dissertations

Nanosecond pulsed electric fields (nsPEFs) offer a plethora of opportunities for developing integrative technologies as complements or alternatives to traditional medicine. Studies on the biological effects of nsPEFs in vitro and in vivo have revealed unique characteristics that suggest the potential for minimized risk of complications in patients, such as the ability of unipolar nsEPs to create permanent or transient pores in cell membranes that trigger localized lethal or non-lethal outcomes without consequential heating. A more recent finding was that such responses could be diminished by applying a bipolar pulse instead, a phenomenon dubbed bipolar cancellation, paving the way …


Secretion Of Proteins And Antibody Fragments From Transiently Transfected Endothelial Progenitor Cells, Loree Heller, Reynald Thinard, Melanie Chevalier, Sezgi Arpag, Yu Jing, Ruth Greferath, Richard Heller, Claude Nicolau Jul 2020

Secretion Of Proteins And Antibody Fragments From Transiently Transfected Endothelial Progenitor Cells, Loree Heller, Reynald Thinard, Melanie Chevalier, Sezgi Arpag, Yu Jing, Ruth Greferath, Richard Heller, Claude Nicolau

Bioelectrics Publications

In neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and amyotrophic lateral sclerosis, neuroinflammation can lead to blood-brain barrier (BBB) breakdown. After intravenous or intra-arterial injection into mice, endothelial progenitor cells (EPCs) home to the damaged BBB to promote neurovascular repair. Autologous EPCs transfected to express specific therapeutic proteins offer an innovative therapeutic option. Here, we demonstrate that EPC transfection by electroporation with plasmids encoding the reporter protein GFP or an anti-beta-amyloid antibody fragment (Fab) leads to secretion of each protein. We also demonstrate the secreted anti-beta-amyloid Fab protein functions in beta-amyloid aggregate solubilization.


Functional Connectivity Of Eeg Is Subject-Specific, Associated With Phenotype, And Different From Fmri, Maximilian Nentwich, Lei Ai, Jens Madsen, Qawi K. Telesford, Stefan Haufe, Michael P. Milham, Lucas C. Parra May 2020

Functional Connectivity Of Eeg Is Subject-Specific, Associated With Phenotype, And Different From Fmri, Maximilian Nentwich, Lei Ai, Jens Madsen, Qawi K. Telesford, Stefan Haufe, Michael P. Milham, Lucas C. Parra

Publications and Research

A variety of psychiatric, behavioral and cognitive phenotypes have been linked to brain ‘’functional connectivity’’ -- the pattern of correlation observed between different brain regions. Most commonly assessed using functional magnetic resonance imaging (fMRI), here, we investigate the connectivity-phenotype associations with functional connectivity measured with electroencephalography (EEG), using phase-coupling. We analyzed data from the publicly available Healthy Brain Network Biobank. This database compiles a growing sample of children and adolescents, currently encompassing 1657 individuals. Among a variety of assessment instruments we focus on ten phenotypic and additional demographic measures that capture most of the variance in this sample. The largest …


Can Transcranial Electrical Stimulation Motor Threshold Estimate Individualized Tdcs Doses Over The Prefrontal Cortex? Evidence From Reverse-Calculation Electric Field Modeling, Kevin A. Caulfield, Bashar W. Badran, Xingbao Li, Marom Bikson, Mark S. George May 2020

Can Transcranial Electrical Stimulation Motor Threshold Estimate Individualized Tdcs Doses Over The Prefrontal Cortex? Evidence From Reverse-Calculation Electric Field Modeling, Kevin A. Caulfield, Bashar W. Badran, Xingbao Li, Marom Bikson, Mark S. George

Publications and Research

No abstract provided.


Probing Nanoelectroporation And Resealing Of The Cell Membrane By The Entry Of Ca2+ And Ba2+ Ions, Wenfei Bo, Mantas Silkunas, Uma Mangalanathan, Vitalij Novickij, Maura Casciola, Iurii Semenov, Shu Xiao, Olga N. Pakhomova, Andrei G. Pakhomov May 2020

Probing Nanoelectroporation And Resealing Of The Cell Membrane By The Entry Of Ca2+ And Ba2+ Ions, Wenfei Bo, Mantas Silkunas, Uma Mangalanathan, Vitalij Novickij, Maura Casciola, Iurii Semenov, Shu Xiao, Olga N. Pakhomova, Andrei G. Pakhomov

Bioelectrics Publications

The principal bioeffect of the nanosecond pulsed electric field (nsPEF) is a lasting cell membrane permeabilization, which is often attributed to the formation of nanometer-sized pores. Such pores may be too small for detection by the uptake of fluorescent dyes. We tested if Ca2+, Cd2+, Zn2+, and Ba2+ ions can be used as nanoporation markers. Time-lapse imaging was performed in CHO, BPAE, and HEK cells loaded with Fluo-4, Calbryte, or Fluo-8 dyes. Ca2+ and Ba2+ did not change fluorescence in intact cells, whereas their entry after nsPEF increased fluorescence within <1 ms. The threshold for one 300-ns pulse was at 1.5–2 kV/cm, much lower than >7 …


Transcranial Electrical Stimulation Motor Threshold Can Estimate Individualized Tdcs Dosage From Reverse-Calculation Electric-Field Modeling, Kevin A. Caulfield, Bashar W. Badran, William H. Devries, Philipp M. Summers, Emma Kofmehl, Xingbao Li, Jeffrey J. Borckardt, Marom Bikson, Mark S. George Apr 2020

Transcranial Electrical Stimulation Motor Threshold Can Estimate Individualized Tdcs Dosage From Reverse-Calculation Electric-Field Modeling, Kevin A. Caulfield, Bashar W. Badran, William H. Devries, Philipp M. Summers, Emma Kofmehl, Xingbao Li, Jeffrey J. Borckardt, Marom Bikson, Mark S. George

Publications and Research

Background

Unique amongst brain stimulation tools, transcranial direct current stimulation (tDCS) currently lacks an easy or widely implemented method for individualizing dosage.

Objective

We developed a method of reverse-calculating electric-field (E-field) models based on Magnetic Resonance Imaging (MRI) scans that can estimate individualized tDCS dose. We also evaluated an MRI-free method of individualizing tDCS dose by measuring transcranial magnetic stimulation (TMS) motor threshold (MT) and single pulse, suprathreshold transcranial electrical stimulation (TES) MT and regressing it against E-field modeling. Key assumptions of reverse-calculation E-field modeling, including the size of region of interest (ROI) analysis and the linearity of multiple E-field …


Transcutaneous Auricular Vagus Nerve Stimulation-Paired Rehabilitation For Oromotor Feeding Problems In Newborns: An Open-Label Pilot Study, Bashar W. Badran, Dorothea D. Jenkins, Daniel Cook, Sean Thompson, Morgan Darcy, William H. Devries, Georgia Mappin, Philipp Summers, Marom Bikson, Mark S. George Mar 2020

Transcutaneous Auricular Vagus Nerve Stimulation-Paired Rehabilitation For Oromotor Feeding Problems In Newborns: An Open-Label Pilot Study, Bashar W. Badran, Dorothea D. Jenkins, Daniel Cook, Sean Thompson, Morgan Darcy, William H. Devries, Georgia Mappin, Philipp Summers, Marom Bikson, Mark S. George

Publications and Research

Neonates born premature or who suffer brain injury at birth often have oral feeding dysfunction and do not meet oral intake requirements needed for discharge. Low oral intake volumes result in extended stays in the hospital (>2 months) and can lead to surgical implant and explant of a gastrostomy tube (G-tube). Prior work suggests pairing vagus nerve stimulation (VNS) with motor activity accelerates functional improvements after stroke, and transcutaneous auricular VNS (taVNS) has emerged as promising noninvasive form of VNS. Pairing taVNS with bottle-feeding rehabilitation may improve oromotor coordination and lead to improved oral intake volumes, ultimately avoiding the …


Enhanced Tes And Tdcs Computational Models By Meninges Emulation, Jimmy Jiang, Dennis Q. Truong, Zeinab Esmaeilpour, Yu Huang, Bashar W. Badran, Marom Bikson Jan 2020

Enhanced Tes And Tdcs Computational Models By Meninges Emulation, Jimmy Jiang, Dennis Q. Truong, Zeinab Esmaeilpour, Yu Huang, Bashar W. Badran, Marom Bikson

Publications and Research

Objective. Understanding how current reaches the brain during transcranial electrical stimulation (tES) underpins efforts to rationalize outcomes and optimize interventions. To this end, computational models of current flow relate applied dose to brain electric field. Conventional tES modeling considers distinct tissues like scalp, skull, cerebrospinal fluid (CSF), gray matter and white matter. The properties of highly conductive CSF are especially important. However, modeling the space between skull and brain as entirely CSF is not an accurate representation of anatomy. The space conventionally modeled as CSF is approximately half meninges (dura, arachnoid, and pia) with lower conductivity. However, the resolution …


Effects Of Weak Electric Fields On Long-Term Synaptic Plasticity, Gregory Kronberg Jan 2020

Effects Of Weak Electric Fields On Long-Term Synaptic Plasticity, Gregory Kronberg

Dissertations and Theses

Transcranial direct current stimulation (tDCS) is a technique where a weak direct electrical current is applied to the scalp with the goal of stimulating the brain. There is tremendous interest in the use of tDCS for treating brain disorders and improving brain function. However, the effects of tDCS have been highly variable across studies, leading to a debate over its efficacy. A major challenge is therefore to design tDCS protocols that yield predictable effects, which will require a better understanding of its basic mechanisms of action. One commonly discussed mechanism is that tDCS may alter synaptic plasticity, but the biophysics …


Electropermeabilization Does Not Correlate With Plasma Membrane Lipid Oxidation, Olga Michel, Andrei G. Pakhomov, Maura Casciola, Jolanta Saczko, Julita Kulbacka, Olga N. Pakhomova Dec 2019

Electropermeabilization Does Not Correlate With Plasma Membrane Lipid Oxidation, Olga Michel, Andrei G. Pakhomov, Maura Casciola, Jolanta Saczko, Julita Kulbacka, Olga N. Pakhomova

Bioelectrics Publications

The permeabilized condition of the cell membrane after electroporation can last minutes but the underlying mechanisms remain elusive. Previous studies suggest that lipid peroxidation could be responsible for the lasting leaky state of the membrane. The present study aims to link oxidation within the plasma membrane of live cells to permeabilization by electric pulses. We have introduced a method for the detection of oxidation by ratiometric fluorescence measurements of BODIPY-C11 dye using total internal reflection fluorescence (TIRF) microscopy, limiting the signal to the cell membrane. CHO-K1 cells were cultured on glass coverslips coated with an electroconductive indium tin oxide (ITO) …


Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu Aug 2019

Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu

Mechanical Engineering Research Theses and Dissertations

My research focuses on electrokinetic transport. Particularly, in this dissertation, we focus on fabrication and testing of micro electrodes with nanostructured surfaces to minimize the electrode polarization (EP) effects for biosensor applications. In the first study, electrochemical deposition of gold nanoparticles on to planar gold electrodes was used to generate rough surfaces. Dendritic nanostructures that reduced EP up to two orders of magnitude was obtained by optimizing the deposition conditions. These structures also enhanced dielectrophoresis (DEP) response of our bio-chips, making them usable in physiological buffers. In further studies we discovered a universal scaling of EP in the frequency domain, …


Coupled Influence Of Heart Rate Variability And Subcellular Calcium Heterogeneity On Cardiac Electromechanical Dynamics, Vrishti M. Phadumdeo, Seth H. Weinberg Ph.D May 2019

Coupled Influence Of Heart Rate Variability And Subcellular Calcium Heterogeneity On Cardiac Electromechanical Dynamics, Vrishti M. Phadumdeo, Seth H. Weinberg Ph.D

Biology and Medicine Through Mathematics Conference

No abstract provided.


Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel May 2019

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel

University Scholar Projects

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …


Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel May 2019

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel

Honors Scholar Theses

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …


Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty May 2019

Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty

Graduate Theses and Dissertations

The conglomeration of myriad activities in neural systems often results in prominent oscillations. The primary goal of the research presented in this thesis was to study effects of sensory stimulus on the olfactory system of rats, focusing on the olfactory bulb (OB) and the anterior piriform cortex (aPC). Extracellular electrophysiological measurements revealed distinct frequency bands of oscillations in OB and aPC. However, how these oscillatory fluctuations help the animal to process sensory input is not clearly understood. Here we show high frequency oscillations in olfactory bulb carry feedforward signals to anterior piriform cortex whereas feedback from the aPC is predominantly …