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Full-Text Articles in Life Sciences

Donor Platelet Plasma Components Inactivate Sensitive And Multidrug Resistant Acinetobacter Baumannii Isolates, Chelsea M. Edelblute, Olga N. Pakhomova, Fanying Li, Barbara Y. Hargrave, Loree C. Heller Dec 2015

Donor Platelet Plasma Components Inactivate Sensitive And Multidrug Resistant Acinetobacter Baumannii Isolates, Chelsea M. Edelblute, Olga N. Pakhomova, Fanying Li, Barbara Y. Hargrave, Loree C. Heller

Bioelectrics Publications

Acinetobacter baumannii is an environmentally resilient healthcare-associated opportunistic pathogen responsible for infections at many body sites. In the last 10 years, clinical strains resistant to many or all commonly used antibiotics have emerged globally. With few antimicrobial agents in the pharmaceutical pipeline, new and alternative agents are essential. Platelets secrete a large number of proteins, including proteins with antimicrobial activity. In a previous study, we demonstrated that donor platelet supernatants and plasma significantly inhibited the growth of a reference strain of A. baumannii in broth and on skin. This inhibition appeared to be unrelated to the platelet activation state. In …


P53: "The Wall Watcher", Nektarios Barabutis, John D. Catravas Oct 2015

P53: "The Wall Watcher", Nektarios Barabutis, John D. Catravas

Bioelectrics Publications

No abstract provided.


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 …


Dose-Dependent Atp Depletion And Cancer Cell Death Following Calcium Electroporation, Relative Effect Of Calcium Concentration And Electric Field Strength, Emilie Louise Hansen, Esin Bengisu Sozer, Stefania Romeo, Stine Krog Frandsen, P. Thomas Vernier, Julie Gehl Jan 2015

Dose-Dependent Atp Depletion And Cancer Cell Death Following Calcium Electroporation, Relative Effect Of Calcium Concentration And Electric Field Strength, Emilie Louise Hansen, Esin Bengisu Sozer, Stefania Romeo, Stine Krog Frandsen, P. Thomas Vernier, Julie Gehl

Bioelectrics Publications

Background: Electroporation, a method for increasing the permeability of membranes to ions and small molecules, is used in the clinic with chemotherapeutic drugs for cancer treatment (electrochemotherapy). Electroporation with calcium causes ATP (adenosine triphosphate) depletion and cancer cell death and could be a novel cancer treatment. This study aims at understanding the relationship between applied electric field, calcium concentration, ATP depletion and efficacy. Methods: In three human cell lines — H69 (small-cell lung cancer), SW780 (bladder cancer), and U937 (leukaemia), viability was determined after treatment with 1, 3, or 5 mM calcium and eight 99 μs pulses with 0.8, 1.0, …


Effects Of Nanosecond Pulse Electric Fields On Cellular Elasticity, Diganta Dutta, Anthony Asmar, Michael W. Stacey Jan 2015

Effects Of Nanosecond Pulse Electric Fields On Cellular Elasticity, Diganta Dutta, Anthony Asmar, Michael W. Stacey

Bioelectrics Publications

We investigated the effects of a single 60 nanosecond pulsed electric field (nsPEF) of low (15 kV/cm) and high (60 kV/cm) field strengths on cellular morphology and membrane elasticity in Jurkat cells using fluorescent microscopy and atomic force microscopy (AFM). We performed force displacement measurements on cells using AFM and calculated the Young's modulus for membrane elasticity. Differential effects were observed depending upon pulsing conditions. We found that a single nsPEF of low field strength did not induce any apparent cytoskeletal breakdown and had minor morphological changes. Interestingly, force measurements and calculation of Young's modulus showed a significant decrease in …


Mechanisms Of Nanosecond Pulsed Electric Field (Nspef)-Induced Cell Death In Cells And Tumors, Stephen J. Beebe Jan 2015

Mechanisms Of Nanosecond Pulsed Electric Field (Nspef)-Induced Cell Death In Cells And Tumors, Stephen J. Beebe

Bioelectrics Publications

The evolution of pulse power technology from high power physics to biology and medicine places nanosecond pulsed electric fields (nsPEFs) in positions for in vitro and in vivo applications as non-ligand agonists that not only bypass plasma membrane receptors for induction of intracellular signaling pathways, but also bypass intracellular oncogenic impasses to induce cell death by regulated mechanisms. Based on work reviewed here, a likely scenario for cell and tumor demise includes nsPEF-induced permeabilization of the plasma membrane, Ca2+ influx, dissipation of the mitochondrial membrane potential, which is likely due to events beyond permeabilization of the inner mitochondrial membrane, cytochrome …


Increased Tissue Temperature Improves Electro-Transfer Mediated Gene Delivery To Skin, Anna Bulysheva, Amy Donate, Chelsea Edelblute, Derrick Jung, Karl Schoenbach, Richard Heller Jan 2015

Increased Tissue Temperature Improves Electro-Transfer Mediated Gene Delivery To Skin, Anna Bulysheva, Amy Donate, Chelsea Edelblute, Derrick Jung, Karl Schoenbach, Richard Heller

Bioelectrics Publications

[Introduction] Developing an optimal gene electro-transfer system for delivery of plasmid DNA to the skin in vivo has been challenging with expression often confined in the epithelium requiring high voltage electric fields, which can cause cellular and tissue damage. Minimizing such damage, while optimizing gene expression profiles, are highly desirable for therapeutic applications of gene delivery to the skin. Cell membrane fluidity is temperature dependent, thus moderate temperature elevation can increase membrane fluidity. Utilizing this concept, we developed a novel gene electro-transfer electrode for in vivo applications with ability to heat tissue with a laser integrated into a four pin …


Gadolinium Modifies The Cell Membrane To Inhibit Permeabilization By Nanosecond Electric Pulses, Elena C. Gianulis, Andrei G. Pakhomov Jan 2015

Gadolinium Modifies The Cell Membrane To Inhibit Permeabilization By Nanosecond Electric Pulses, Elena C. Gianulis, Andrei G. Pakhomov

Bioelectrics Publications

Lanthanide ions are the only known blockers of permeabilization by electric pulses of nanosecond duration (nsEP), but the underlying mechanisms are unknown. We employed timed applications of Gd3+ before or after nsEP (600-ns, 20 kV/cm) to investigate the mechanism of inhibition, and measured the uptake of the membrane-impermeable YO-PRO-1 (YP) and propidium (Pr) dyes. Gd3+ inhibited dye uptake in a concentration-dependent manner. The inhibition of Pr uptake was always about 2-fold stronger. Gd3+ was effective when added after nsEP, as well as when it was present during nsEP exposure and removed afterward. Pores formed by nsEP in …


Histone Deacetylase Inhibitors Prevent Pulmonary Endothelial Hyperpermeability And Acute Lung Injury By Regulating Heat Shock Protein 90 Function, Atul D. Joshi, Nektarios Barabutis, Charalampos Birmpas, Christiana Dimitropoulou, Gagan Thangjam, Mary Cherian-Shaw, John Dennison, John D. Catravas Jan 2015

Histone Deacetylase Inhibitors Prevent Pulmonary Endothelial Hyperpermeability And Acute Lung Injury By Regulating Heat Shock Protein 90 Function, Atul D. Joshi, Nektarios Barabutis, Charalampos Birmpas, Christiana Dimitropoulou, Gagan Thangjam, Mary Cherian-Shaw, John Dennison, John D. Catravas

Bioelectrics Publications

Transendothelial hyperpermeability caused by numerous agonists is dependent on heat shock protein 90 (Hsp90) and leads to endothelial barrier dysfunction (EBD). Inhibition of Hsp90 protects and restores transendothelial permeability. Hyperacetylation of Hsp90, as by inhibitors of histone deacetylase (HDAC), suppresses its chaperone function and mimics the effects of Hsp90 inhibitors. In this study we assessed the role of HDAC in mediating lipopolysaccharide (LPS)-induced transendothelial hyperpermeability and acute lung injury (ALI). We demonstrate that HDAC inhibition protects against LPS-mediated EBD. Inhibition of multiple HDAC by the general inhibitors panobinostat or trichostatin provided protection against LPS-induced transendothelial hyperpermeability, acetylated and suppressed Hsp90 …


Diffuse, Non-Polar Electropermeabilization And Reduced Propidium Uptake Distinguish The Effect Of Nanosecond Electric Pulses, Iurii Semenov, Christian W. Zemlin, Olga N. Pakhomova, Shu Xiao, Andrei G. Pakhomov Jan 2015

Diffuse, Non-Polar Electropermeabilization And Reduced Propidium Uptake Distinguish The Effect Of Nanosecond Electric Pulses, Iurii Semenov, Christian W. Zemlin, Olga N. Pakhomova, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Ca2+ activation and membrane electroporation by 10-ns and 4-ms electric pulses (nsEP and msEP) were compared in rat embryonic cardiomyocytes. The lowest electric field which triggered Ca2+ transients was expectedly higher for nsEP (36 kV/cm)than forms EP (0.09 kV/cm) but the respective doses were similar (190 and460 mJ/g). At higher intensities, both stimuli triggered prolonged firing in quiescent cells. An increase of basal Ca2+ level by N10 nM in cells with blocked voltage-gated Ca2+ channels and depleted Ca2+ depot occurred at 63 kV/cm (nsEP) or 0.14 kV/cm (msEP) and was regarded as electroporation threshold. These …


In Situ Oh Generation From O2- And H2o2 Plays A Critical Role In Plasma Induced Cell Death, Dehui Xu, Dingxing Liu, Biqing Wang, Chen Chen, Zeyu Chen, Dong Li, Yanjie Yang, Hailan Chen, Michael G. Kong Jan 2015

In Situ Oh Generation From O2- And H2o2 Plays A Critical Role In Plasma Induced Cell Death, Dehui Xu, Dingxing Liu, Biqing Wang, Chen Chen, Zeyu Chen, Dong Li, Yanjie Yang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Reactive oxygen and nitrogen species produced by cold atmospheric plasma (CAP) are considered to be the most important species for biomedical applications, including cancer treatment. However, it is not known which species exert the greatest biological effects, and the nature of their interactions with tumor cells remains ill-defined. These questions were addressed in the present study by exposing human mesenchymal stromal and LP-1 cells to reactive oxygen and nitrogen species produced by CAP and evaluating cell viability. Superoxide anion (O2-) and hydrogen peroxide (H2O2) were the two major species present in plasma, but their …


Presence And Localization Of Pro-And Mature Forms Of Biglycan And Decorin In Human Costal Cartilage Derived From Chest Wall Deformities, Anthony Asmar, A. Werner, R. E. Kelly Jr., A. Fecteau, Michael W. Stacey Jan 2015

Presence And Localization Of Pro-And Mature Forms Of Biglycan And Decorin In Human Costal Cartilage Derived From Chest Wall Deformities, Anthony Asmar, A. Werner, R. E. Kelly Jr., A. Fecteau, Michael W. Stacey

Bioelectrics Publications

Costal cartilage is a type of hyaline cartilage that forms rod-like structures that connect the ribs to the sternum. The most common chest wall deformities, pectus excavatum and pectus carinatum involved efective costal cartilage resulting in sternal displacement. Costal cartilage is not widely studied leaving little insight into possible factors involved in the pathogenesis of these pectus deformities. This study focused on the presence and distribution of two important regulators of collagen fibrillogenesis and organization, biglycan and decorin. Immunohistochemical analysis of transverse cross sections of normal and deformed costal cartilage revealed that biglycan and decorin mainly localized in the territorial …


Electroporation Of Mammalian Cells By Nanosecond Electric Field Oscillations And It's Inhibition By The Electric Field Reversal, Elena C. Gianulis, Jimo Lee, Chunqi Jiang, Shu Xiao, Bennet L. Ibey, Andrei G. Pakhomov Jan 2015

Electroporation Of Mammalian Cells By Nanosecond Electric Field Oscillations And It's Inhibition By The Electric Field Reversal, Elena C. Gianulis, Jimo Lee, Chunqi Jiang, Shu Xiao, Bennet L. Ibey, Andrei G. Pakhomov

Bioelectrics Publications

The present study compared electroporation efficiency of bipolar and unipolar nanosecond electric field oscillations (NEFO). Bipolar NEFO was a damped sine wave with 140 ns first phase duration at 50% height; the peak amplitude of phases 2-4 decreased to 35%, 12%, and 7% of the first phase. This waveform was rectified to produce unipolar NEFO by cutting off phases 2 and 4. Membrane permeabilization was quantified in CHO and GH3 cells by uptake of a membrane integrity marker dye YO-PRO-1 (YP) and by the membrane conductance increase measured by patch clamp. For treatments with 1-20 unipolar NEFO, at 9.6-24 …


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.