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Physiology

Bioelectrics Publications

Articles 1 - 7 of 7

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

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 …

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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 …

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Picosecond To Terahertz Perturbation Of Interfacial Water And Electropermeabilization Of Biological Membranes, P. Thomas Vernier, Zachary A. Levine, Ming-Chak Ho, Shu Xiao, Iurii Semenov, Andrei G. Pakhomov Jan 2015

Picosecond To Terahertz Perturbation Of Interfacial Water And Electropermeabilization Of Biological Membranes, P. Thomas Vernier, Zachary A. Levine, Ming-Chak Ho, Shu Xiao, Iurii Semenov, Andrei G. Pakhomov

Bioelectrics Publications

Non-thermal probing and stimulation with subnanosecond electric pulses and terahertz electromagnetic radiation may lead to new, minimally invasive diagnostic and therapeutic procedures and to methods for remote monitoring and analysis of biological systems, including plants, animals, and humans. To effectively engineer these still-emerging tools, we need an understanding of the biophysical mechanisms underlying the responses that have been reported to these novel stimuli. We show here that subnanosecond (≤500 ps) electric pulses induce action potentials in neurons and cause calcium transients in neuroblastoma-glioma hybrid cells, and we report complementary molecular dynamics simulations of phospholipid bilayers in electric fields in which …

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Introduction To Fifth Special Issue On Electroporation-Based Technologies And Treatments, Damijan Miklavčič, Lluis M. Mir, P. Thomas Vernier Jan 2015

Introduction To Fifth Special Issue On Electroporation-Based Technologies And Treatments, Damijan Miklavčič, Lluis M. Mir, P. Thomas Vernier

Bioelectrics Publications

This special issue of the Journal of Membrane Biology contains reports on recent developments in the field of electroporation by participants in the International Workshop and Postgraduate Course on Electroporation-Based Technologies and Treatments held in November 2014 in Ljubljana. This was the eighth session of what is now an annual event, first organized in 2003.

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Basic Features Of A Cell Electroporation Model: Illustrative Behavior For Two Very Different Pulses, Reuben S. Son, Kyle C. Smith, Thiruvallur R. Gowrishankar, P. Thomas Vernier, James C. Weaver Jan 2014

Basic Features Of A Cell Electroporation Model: Illustrative Behavior For Two Very Different Pulses, Reuben S. Son, Kyle C. Smith, Thiruvallur R. Gowrishankar, P. Thomas Vernier, James C. Weaver

Bioelectrics Publications

Science increasingly involves complex modeling. Here we describe a model for cell electroporation in which membrane properties are dynamically modified by poration. Spatial scales range from cell membrane thickness (5 nm) to a typical mammalian cell radius (10 μm), and can be used with idealized and experimental pulse waveforms. The model consists of traditional passive components and additional active components representing nonequilibrium processes. Model responses include measurable quantities: transmembrane voltage, membrane electrical conductance, and solute transport rates and amounts for the representative "long" and "short" pulses. The long pulse-1.5 kV/cm, 100 μs-evolves two pore subpopulations with a valley at ~5 …

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Introduction To Fourth Special Issue On Electroporation-Based Technologies And Treatments, Damijan Miklavčič, Lluis M. Mir, P. Thomas Vernier Jan 2014

Introduction To Fourth Special Issue On Electroporation-Based Technologies And Treatments, Damijan Miklavčič, Lluis M. Mir, P. Thomas Vernier

Bioelectrics Publications

This fourth special electroporation-based technologies and treatments issue of the Journal of Membrane Biology contains reports on recent developments in the field of electroporation by participants in the 7th International Workshop and Postgraduate Course on electroporation based technologies and treatments (EBTT 2013) held in Ljubljana, November 17–23, 2013. The 65 participants included faculty members, invited lecturers, special guests, and young scientists, and students from 16 countries. In addition to lectures on the fundamentals, this year’s sessions included talks on microbial inactivation by pulsed electric fields, modeling of intracellular electroporation, electroporation in food processing, and electrotransfer-facilitated DNA vaccination.

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Electric Field Exposure Triggers And Guides Formation Of Pseudopod-Like Blebs In U937 Monocytes, Mikhail A. Rassokhin, Andrei G. Pakhomov Jan 2012

Electric Field Exposure Triggers And Guides Formation Of Pseudopod-Like Blebs In U937 Monocytes, Mikhail A. Rassokhin, Andrei G. Pakhomov

Bioelectrics Publications

We describe a new phenomenon of anodotropic pseudopod-like blebbing in U937 cells stimulated by nanosecond pulsed electric field (nsPEF). In contrast to "regular," round-shaped blebs, which are often seen in response to cell damage, pseudopod-like blebs (PLBs) formed as longitudinal membrane protrusions toward anode. PLB length could exceed the cell diameter in 2 min of exposure to 60-ns, 10-kV/cm pulses delivered at 10-20 Hz. Both PLBs and round-shaped nsPEF-induced blebs could be efficiently inhibited by partial isosmotic replacement of bath NaCl for a larger solute (sucrose), thereby pointing to the colloid-osmotic water uptake as the principal driving force for bleb …

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