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Electroporation Safety Factor Of 300 Nanosecond And 10 Millisecond Defibrillation In Langendorff-Perfused Rabbit Hearts, Johanna U. Neuber, Andrei G. Pakhomov, Christian W. Zemlin

Bioelectrics Publications

Aims

Recently, a new defibrillation modality using nanosecond pulses was shown to be effective at much lower energies than conventional 10 millisecond monophasic shocks in ex vivo experiments. Here we compare the safety factors of 300 nanosecond and 10 millisecond shocks to assess the safety of nanosecond defibrillation.

Methods and results

The safety factor, i.e. the ratio of median effective doses (ED50) for electroporative damage and defibrillation, was assessed for nanosecond and conventional (millisecond) defibrillation shocks in Langendorff-perfused New Zealand white rabbit hearts. In order to allow for multiple shock applications in a single heart, a pair of needle electrodes …

Growth In A Biofilm Sensitizes Cutibacterium Acnes To Nanosecond Pulsed Electric Fields, Asia Poudel, Adenrele Oludiran, Esin B. Sözer, Maura Casciola, Erin B. Purcell, Claudia Muratori

Bioelectrics Publications

The Gram-positive anaerobic bacterium Cutibacterium acnes (C. acnes) is a commensal of the human skin, but also an opportunistic pathogen that contributes to the pathophysiology of the skin disease acne vulgaris. C. acnes can form biofilms; cells in biofilms are more resilient to antimicrobial stresses. Acne therapeutic options such as topical or systemic antimicrobial treatments often show incomplete responses. In this study we measured the efficacy of nanosecond pulsed electric fields (nsPEF), a new promising cell and tissue ablation technology, to inactivate C. acnes. Our results show that all tested nsPEF doses (250 to 2000 pulses, 280 ns pulses, …

Moderate Heat-Assisted Gene Electrotransfer As A Potential Delivery Approach For Protein Replacement Therapy Through The Skin, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller

Bioelectrics Publications

Gene-based approaches for protein replacement therapies have the potential to reduce the number of administrations. Our previous work demonstrated that expression could be enhanced and/or the applied voltage reduced by preheating the tissue prior to pulse administration. In the current study, we utilized our 16-pin multi-electrode array (MEA) and incorporated nine optical fibers, connected to an infrared laser, between each set of four electrodes to heat the tissue to 43 °C. For proof of principle, a guinea pig model was used to test delivery of reporter genes. We observed that when the skin was preheated, it was possible to achieve …

Moderate Heat-Assisted Gene Electrotransfer For Cutaneous Delivery Of A Dna Vaccine Against Hepatitis B Virus, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller

Bioelectrics Publications

An estimated 350 million people are living with chronic Hepatitis B virus (HBV) worldwide. Preventative HBV vaccination in infants has reduced the disease burden; however, insufficient immunization programs and access obstacles leave vulnerable populations at risk for infection in endemic regions. Gene electrotransfer (GET) using a noninvasive multielectrode array (MEA) provides an alternative platform for DNA vaccination in the skin. DNA vaccines are nonlive and nonreplicating and temperature stable unlike their counterparts. In addition, their simple engineering allows them to be manufactured quickly at a low cost. In the current work, we present the combination of GET and moderate heating …

Peculiarities Of Neurostimulation By Intense Nanosecond Pulsed Electric Fields: How To Avoid Firing In Peripheral Nerve Fibers, Vitalii Kim, Emily Gudvangen, Oleg Kondratiev, Luis Redondo, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Intense pulsed electric fields (PEF) are a novel modality for the efficient and targeted ablation of tumors by electroporation. The major adverse side effects of PEF therapies are strong involuntary muscle contractions and pain. Nanosecond-range PEF (nsPEF) are less efficient at neurostimulation and can be employed to minimize such side effects. We quantified the impact of the electrode configuration, PEF strength (up to 20 kV/cm), repetition rate (up to 3 MHz), bi- and triphasic pulse shapes, and pulse duration (down to 10 ns) on eliciting compound action potentials (CAPs) in nerve fibers. The excitation thresholds for single unipolar but not …