@article {184, title = {Auricular transcutaneous vagus nerve stimulation improves memory persistence in na{\"\i}ve mice and in an intellectual disability mouse model}, journal = {Brain Stimulation}, volume = {13}, year = {2020}, pages = {494-498}, chapter = {494}, doi = {10.1016/j.brs.2019.12.024}, url = {https://doi.org/10.1016/j.brs.2019.12.024}, author = {Anna V{\'a}zquez-Oliver and Cecilia Brambilla-Pisoni and Mikel Domingo-Gainza and Rafael Maldonado and Antoni Ivorra and Andr{\'e}s Ozaita} } @article {197, title = {Physiological changes may dominate the electrical properties of liver during reversible electroporation: measurements and modelling}, journal = {Bioelectrochemistry}, volume = {(In Press, Journal Pre-proof)}, year = {2020}, doi = {10.1016/j.bioelechem.2020.107627}, url = {https://doi.org/10.1016/j.bioelechem.2020.107627}, author = {Tomas Garcia-Sanchez and Damien Voyer and Clair Poignard and Lluis M. Mir} } @article {195, title = {Pulsed radiofrequency for chronic pain: in vitro evidence of an electroporation mediated calcium uptake}, journal = {Bioelectrochemistry}, volume = {136}, year = {2020}, pages = {107624}, chapter = {107624}, doi = {10.1016/j.bioelechem.2020.107624}, author = {Borja Mercadal and Rub{\'e}n Vicente and Antoni Ivorra} } @article {171, title = {Irreversible electroporation for the treatment of cardiac arrhythmias}, journal = {Expert Review of Cardiovascular Therapy}, volume = {16}, year = {2018}, pages = {349-360 }, chapter = {349}, doi = {10.1080/14779072.2018.1459185}, url = {https://www.tandfonline.com/doi/abs/10.1080/14779072.2018.1459185}, author = {Alan Sugrue and Elad Maor and Antoni Ivorra and Vaibhav Vaidya and Chance Witt and Suraj Kapa and Samuel Asirvatham} } @article {166, title = {Focused Transhepatic Electroporation Mediated by Hypersaline Infusion throuth the Portal Vein in Rat Model. Preliminary Results on Differential Conductivity}, journal = {Radiology and Oncology}, volume = {51}, year = {2017}, pages = {415-421}, chapter = {415}, author = {Clara Pa{\~n}ella and Q. Castellv{\'\i} and Xavier Moll and Rita Quesada and Alberto Villanueva and M. Iglesias and Dolores Naranjo and Patricia S{\'a}nchez-Vel{\'a}zquez and Andaluz, Anna and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @article {158, title = {Long-term effectiveness of irreversible electroporation in a murine model of colorectal liver metastasis}, journal = {Scientific reports}, volume = {7}, year = {2017}, chapter = {44821}, doi = {10.1038/srep44821}, author = {Patricia S{\'a}nchez-Vel{\'a}zquez and Q. Castellv{\'\i} and Alberto Villanueva and M. Iglesias and Rita Quesada and Clara Pa{\~n}ella and Marta C{\'a}ceres and Dimitri Dorcaratto and Andaluz, Anna and Xavier Moll and Jos{\'e} M. Burd{\'\i}o and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @article {151, title = {Dependence of electroporation detection threshold on cell radius: an explanation to observations non compatible with Schwan{\textquoteright}s equation model}, journal = {Journal of Membrane Biology}, volume = {249}, year = {2016}, pages = {663-676}, chapter = {663}, abstract = {

It is widely accepted that electroporation occurs when the cell transmembrane voltage induced by an external applied electric field reaches a threshold. Under this assumption, in order to trigger electroporation in a spherical cell, Schwan{\textquoteright}s equation leads to an inversely proportional relationship between the cell radius and the minimum magnitude of the applied electric field. And, indeed, several publications report experimental evidences of an inverse relationship between the cell size and the field required to achieve electroporation. However, this dependence is not always observed or is not as steep as predicted by Schwan{\textquoteright}s equation. The present numerical study attempts to explain these observations that do not fit Schwan{\textquoteright}s equation on the basis of the interplay between cell membrane conductivity, permeability and transmembrane voltage. For that, a single cell in suspension was modeled and it was determined the electric field necessary to achieve electroporation with a single pulse according to two effectiveness criteria: a specific permeabilization level, understood as the relative area occupied by the pores during the pulse, and a final intracellular concentration of a molecule due to uptake by diffusion after the pulse, during membrane resealing. The results indicate that plausible model parameters can lead to divergent dependencies of the electric field threshold on the cell radius. These divergent dependencies were obtained through both criteria and using two different permeabilization models. This suggests that the interplay between cell membrane conductivity, permeability and transmembrane voltage might be the cause of results which are non compatible with the Schwan{\textquoteright}s equation model.\ 

}, author = {Borja Mercadal and P. Thomas Vernier and Antoni Ivorra} } @article {150, title = {Irreversible electroporation of the liver: is there a safe limit to the ablation volume?}, journal = {Scientific Reports}, volume = {6}, year = {2016}, pages = {23781}, doi = {10.1038/srep23781}, author = {Patricia S{\'a}nchez-Vel{\'a}zquez and Q. Castellv{\'\i} and Alberto Villanueva and Rita Quesada and Clara Pa{\~n}ella and Marta C{\'a}ceres and Dimitri Dorcaratto and Andaluz, Anna and Xavier Moll and Trujillo, Macarena and Jos{\'e} M. Burd{\'\i}o and Berjano, Enrique and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @conference {132, title = {Charge Counter for Performing Active Charge-Balance in Miniaturized Electrical Stimulators}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering SE - 64}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, month = {2015///}, pages = {256 - 259}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, keywords = {active charge-balance, dc-blocking capacitor, FES, miniaturization, rectifier}, isbn = {978-3-319-11127-8}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_64}, author = {Laura Becerra-Fajardo and Antoni Ivorra}, editor = {Lackovi{\'c}, Igor and Vasic, Darko} } @conference {139, title = {Impact of Liver Vasculature on Electric Field Distribution during Electroporation Treatments: An Anatomically Realistic Numerical Study}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, pages = {573-576}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, keywords = {blood vessels, conductivity, Electroporation, numerical modeling}, isbn = {978-3-319-11127-8}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_143}, author = {Radwan Qasrawi and Antoni Ivorra}, editor = {Lackovi{\'c}, Igor and Vasic, Darko} } @article {142, title = {In vivo assessment of corneal barrier function through non-invasive impedance measurements using a flexible probe}, journal = {Journal of Physics: Conference Series}, volume = {434}, year = {2013}, pages = {012072}, abstract = {

The cornea is a transparent structure composed of three layers: the epithelium, the stroma and the endothelium. To maintain its ransparency the stroma remains in a constant state of dehydration. Consequently, any ion flow disorder through the covering layers can compromise the barrier function and, therefore the corneal homeostasis. Since ionic permeability has a fundamental impact on the passive electrical properties of living tissues, in this work it is proposed and demonstrated a diagnosis method based on tetrapolar impedance measurements performed by electrodes placed on the corneal surface. The contribution of each cornea layer to the total measured impedance has been analysed over a frequency range. Following the obtained guidelines, a flexible probe with integrated electrodes has been developed and manufactured using SU-8 photoresin. The feasibility of the proposed method has been evaluated in vivo by monitoring corneal epithelium wound healing. Obtained impedance measurements have been compared with measurements of permeability to sodium fluorescein from different excised corneas. Successful results demonstrate the feasibility of this novel flexible sensor and its capability to quantify corneal permeability in vivo in a noninvasive way.

}, url = {http://stacks.iop.org/1742-6596/434/i=1/a=012072}, author = {A Guimera and X Illa and E Traver and S Marchan and C Herrero and C Lagunas and M J Maldonado and Antoni Ivorra and R Villa} } @article {Ivorra2010, title = {{Electrical modeling of the influence of medium conductivity on electroporation.}}, journal = {Physical chemistry chemical physics : PCCP}, volume = {12}, number = {34}, year = {2010}, pages = {10055{\textendash}64}, abstract = {

Electroporation is the phenomenon in which cell membrane permeability is increased by exposing the cell to short high electric field pulses. Experimental data show that the amount of permeabilization depends on the conductivity of the extracellular medium. If medium conductivity decreases then it is necessary to deliver a pulse of larger field amplitude in order to achieve the same effect. Models that do not take into account the permeabilization effect on the membrane conductivity cannot reproduce qualitatively the experimental observations. Here we employ an exponential function for describing the strong dependence of membrane conductivity on transmembrane potential. Combining that model with numerical methods we demonstrate that the dependence on medium conductivity can be explained as being the result of increased membrane conductance due to electroporation. As experimentally observed, extracellular conductivities of about 1 and 0.1 S m(-1) yield very similar results, however, for lower conductivities (\<0.01 S m(-1)) the model predicts that significantly higher field magnitudes will be required to achieve the same amount of permeabilization.

}, keywords = {Biological, Cell Membrane, Cell Membrane Permeability, Cell Membrane: metabolism, Diffusion, Electric Conductivity, Electroporation, Membrane Potentials, Models, Reproducibility of Results}, issn = {1463-9084}, doi = {10.1039/c004419a}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20585676}, author = {Antoni Ivorra and J. Villemejane and L.M. Mir} } @inbook {Silve2010, title = {{Nanosecond pulsed electric field delivery to biological samples: difficulties and potential solutions}}, booktitle = {Advanced Electroporation Techniques in Biology and Medicine}, year = {2010}, pages = {353{\textendash}370}, abstract = {

In this chapter we discuss particular features of the nanosecond electric pulsed fields (nsPEFs) that must be taken into account when experimenting on their delivery to biological samples. The purpose of the chapter is to provide future users of this technology with some advice on how to correctly apply it. It is first analyzed how propagation related phenomena can impact on the actual electric field pulse that is applied to the sample. In particular, it is shown that impedance matching for the exposure chamber will be a key element. It is then proposed to employ monitoring systems for voltage and current signals and some indications about their use and limitations are given. Finally, the electrochemical and thermal consequences of nsPEFs delivery are also discussed. We conclude that only excellent experimental conditions can result in robust, controlled and reproducible data on the nsPEFs biological effects.

}, keywords = {breakdown of dielectric, electrochemical reactions, impedance, matching, materials, monitoring, nanosecond electric pulses, thermal effects, transmission line, waves propagation}, isbn = {978-1-439-81906-7}, author = {Aude Silve and J. Villemejane and Joubert, V. and Antoni Ivorra and L.M. Mir} } @article {Guimera2010, title = {{Non-invasive assessment of corneal endothelial permeability by means of electrical impedance measurements.}}, journal = {Medical engineering \& physics}, volume = {32}, number = {10}, year = {2010}, pages = {1107{\textendash}15. {\textcopyright} 2010 IPEM. Published by Elsevier Ltd.}, abstract = {

The permeability of the corneal endothelial layer has an important role in the correct function of the cornea. Since ionic permeability has a fundamental impact on the passive electrical properties of living tissues, here it is hypothesized that impedance methods can be employed for assessing the permeability of the endothelial layer in a minimally invasive fashion. Precisely, the main objective of the present study is to develop and to analyze a minimally invasive method for assessing the electrical properties of the corneal endothelium, as a possible diagnostic tool for the evaluation of patients with endothelial dysfunction. A bidimensional model consisting of the main corneal layers and a four-electrode impedance measurement setup placed on the epithelium has been implemented and analyzed by means of the finite elements method (FEM). In order to obtain a robust indicator of the permeability of the endothelium layer, the effect of the endothelium electrical properties on the measured impedance has been studied together with reasonable variations of the other model layers. Simulation results show that the impedance measurements by means of external electrodes are indeed sufficiently sensitive to the changes in the electrical properties of the endothelial layer. It is concluded that the method presented here can be employed as non-invasive method for assessing endothelial layer function.

}, keywords = {Biomedical Engineering, Biomedical Engineering: methods, Corneal, Corneal: abnormalities, Corneal: metabolism, Corneal: pathology, Electric Impedance, Electric Impedance: diagnostic use, Endothelium, Finite Element Analysis, Humans, Permeability, Reproducibility of Results, Sensitivity and Specificity}, issn = {1873-4030}, doi = {10.1016/j.medengphy.2010.07.016}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20832346}, author = {A Guimera and Antoni Ivorra and Gabriel, G and R Villa} }