@article {Jose2012, title = {{Irreversible electroporation shows efficacy against pancreatic carcinoma without systemic toxicity in mouse models.}}, journal = {Cancer letters}, volume = {317}, number = {1}, year = {2012}, pages = {16{\textendash}23}, abstract = {

Pancreatic ductal adenocarcinoma (PDAC) therapies show limited success. Irreversible electroporation (IRE) is an innovative loco-regional therapy in which high-voltage pulses are applied to induce plasma membrane defects leading to cellular death. In the present study we evaluated the feasibility of IRE against PDAC. IRE treatment exhibited significant antitumor effects and prolonged survival in mice with orthotopic xenografts. Extensive tumor necrosis, reduced tumor cell proliferation and disruption of microvessels were observed at different days post-IRE. Animals had transient increases in transaminases, amylase and lipase enzymes that normalized at 24h post-IRE. These results suggest that IRE could be an effective treatment for locally advanced pancreatic tumors.

}, keywords = {Alanine Transaminase, Alanine Transaminase: blood, Amylases, Amylases: blood, Animals, Aspartate Aminotransferases, Aspartate Aminotransferases: blood, Biological Markers, Biological Markers: blood, Blood Glucose, Blood Glucose: metabolism, Carcinoma, Cell Line, Cell Proliferation, Electrochemotherapy, Electrochemotherapy: adverse effects, Feasibility Studies, Genes, Humans, Lipase, Lipase: blood, Luminescent Measurements, Male, Mice, Microvessels, Microvessels: pathology, Necrosis, Nude, Pancreatic Ductal, Pancreatic Ductal: blood, Pancreatic Ductal: blood supply, Pancreatic Ductal: genetics, Pancreatic Ductal: pathology, Pancreatic Ductal: therapy, Pancreatic Neoplasms, Pancreatic Neoplasms: blood, Pancreatic Neoplasms: blood supply, Pancreatic Neoplasms: genetics, Pancreatic Neoplasms: pathology, Pancreatic Neoplasms: therapy, Reporter, Time Factors, Transfection, Tumor, Xenograft Model Antitumor Assays}, issn = {1872-7980}, doi = {10.1016/j.canlet.2011.11.004}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22079741}, author = {Jos{\'e}, Anabel and Sobrevals, Luciano and Antoni Ivorra and Fillat, Cristina} } @article {Ivorra2011, title = {{Electrochemical prevention of needle-tract seeding.}}, journal = {Annals of biomedical engineering}, volume = {39}, number = {7}, year = {2011}, month = {jul}, pages = {2080{\textendash}9}, abstract = {

Needle-tract seeding refers to the implantation of tumor cells by contamination when instruments, such as biopsy needles, are employed to examine, excise, or ablate a tumor. The incidence of this iatrogenic phenomenon is low but it entails serious consequences. Here, as a new method for preventing neoplasm seeding, it is proposed to cause electrochemical reactions at the instrument surface so that a toxic microenvironment is formed. In particular, the instrument shaft would act as the cathode, and the tissues would act as the electrolyte in an electrolysis cell. By employing numerical models and experimental observations reported by researchers on Electrochemical Treatment of tumors, it is numerically showed that a sufficiently toxic environment of supraphysiological pH can be created in a few seconds without excessive heating. Then, by employing an ex vivo model consisting of meat pieces, validity of the conclusions provided by the numerical model concerning pH evolution is confirmed. Furthermore, a simplified in vitro model based on bacteria, instead of tumor cells, is implemented for showing the plausibility of the method. Depending on the geometry of the instrument, suitable current densities will probably range from about 5 to 200 mA/cm(2), and the duration of DC current delivery will range from a few seconds to a few minutes.

}, keywords = {Animals, Electrochemistry, Electrochemistry: methods, Equipment Contamination, Equipment Contamination: prevention \& control, Humans, Needles, Neoplasm Seeding, Neoplasms, Neoplasms: etiology, Neoplasms: prevention \& control}, issn = {1573-9686}, doi = {10.1007/s10439-011-0295-4}, url = {http://www.ncbi.nlm.nih.gov/pubmed/21400019}, author = {Antoni Ivorra} } @article {Laufer2010, title = {{Electrical impedance characterization of normal and cancerous human hepatic tissue.}}, journal = {Physiological measurement}, volume = {31}, number = {7}, year = {2010}, pages = {995{\textendash}1009. {\textcopyright} 2010 Institute of Physics and IOP Publishing Limited.}, abstract = {

The four-electrode method was used to measure the ex vivo complex electrical impedance of tissues from 14 hepatic tumors and the surrounding normal liver from six patients. Measurements were done in the frequency range 1-400 kHz. It was found that the conductivity of the tumor tissue was much higher than that of the normal liver tissue in this frequency range (from 0.14 +/- 0.06 S m(-1) versus 0.03 +/- 0.01 S m(-1) at 1 kHz to 0.25 +/- 0.06 S m(-1) versus 0.15 +/- 0.03 S m(-1) at 400 kHz). The Cole-Cole models were estimated from the experimental data and the four parameters (rho(0), rho(infinity), alpha, f(c)) were obtained using a least-squares fit algorithm. The Cole-Cole parameters for the cancerous and normal liver are 9 +/- 4 Omega m(-1), 2.2 +/- 0.7 Omega m(-1), 0.5 +/- 0.2, 140 +/- 103 kHz and 50 +/- 28 Omega m(-1), 3.2 +/- 0.6 Omega m(-1), 0.64 +/- 0.04, 10 +/- 7 kHz, respectively. These data can contribute to developing bioelectric applications for tissue diagnostics and in tissue treatment planning with electrical fields such as radiofrequency tissue ablation, electrochemotherapy and gene therapy with reversible electroporation, nanoscale pulsing and irreversible electroporation.

}, keywords = {80 and over, Adult, Aged, Electric Impedance, Electrodes, Female, Humans, Liver, Liver Cirrhosis, Liver Cirrhosis: pathology, Liver Neoplasms, Liver Neoplasms: pathology, Liver: pathology, Male, Middle Aged}, issn = {1361-6579}, doi = {10.1088/0967-3334/31/7/009}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20577035}, author = {Laufer, Shlomi and Antoni Ivorra and Reuter, Victor E and Boris Rubinsky and Solomon, Stephen B} } @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} }