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In order to establish cancer-type-specific electroporation protocols for breast cancer, electroporation was performed in vitro in two modalities: in-suspension and adhered cells. Electroporation of cell suspensions was carried out through commercial electroporation cuvettes whereas a novel electrode for electroporation of adhered cells was designed and manufactured aimed to preserve cell structure, to provide a closer model to an in vivo scenario, and as a means to visualize the mechanical effects of electroporation on the cell membrane by using scanning electron microscopy. Electroporation protocols and electric field thresholds were predicted in silico and experimentally tuned through propidium iodide uptake and cell viability. Three breast-cancer cell lines (BT-20, MCF-7 and HCC1419) and a non-cancerous cell line (BEAS-2B) were used. Cancerous cells responded differently to electroporation depending on the electric parameters, cell histology, the cell culture modality, and the cell morphology (membrane thickness mainly), which was evaluated trough confocal and transmission electron microscopy. Particularly, it was found that electrochemotherapy may represent a promising alternative as an adjuvant treatment of metastatic breast tumours, and as a neoadjuvant therapy for Her2/neu tumours. Oppositely, triple negative breast tumours may show a high sensitivity to electroporation and therefore, they could be efficiently treated with irreversible electroporation. On the other hand, noncancerous cells demanded the highest voltage in both cell culture modalities in order to be electroporated. Hence, these cells in suspension may provide a reliable, easy-to-perform, low-cost model for the development of electroporation protocols for eradication of healthy tissue around a tumour in a safety margin.

The aim of this study was to design an applicator for haemostasis usage needing lower acoustic intensities (880 W/cm(2)) than in previous devices intended for it, which is based on ultrasound propagation FEM modelling using a 2-MHz HIFU transducer.Acoustic field characterisation and numerical simulations in water were performed with and without the proposed applicator. Parameters such as form factor, ellipsoidal shape ratio, and Euclidean distance were used (among others) to compare simulated data with transducer measurements without applicator. A low density polyethylene cone was manufactured from geometries validated from acoustic field modelling. The hollow cone was filled with 10% polyacrylamide gel as a coupling medium with liver phantom or chicken liver. Focal temperature was measured with a thermocouple embedded in the phantom for 1-20 W driving powers for 120 s. Standing wave ratios (SWR) were used as coupling indexes. Ex vivo experimentation in chicken liver was made at 10-20 W.Simulated acoustic patterns showed good concordance with measurements. Experimental focal distance was 20.72 ± 0.24 mm, while the simulated was 19.79 mm (≈4% error). SWR at low power were: 2.01 with transducer emitting in air, 1.53 at applicator tip, and 1.35 after phantom placement. Average SWR at high power was 1.31. Similarity of percentages for data comparison in focal plane was over 60%. Maximum temperature measured at focus was 88.7 °C with 20 W after 85 s.Temperatures reached at focus suggest that this applicator has good efficiency, which notably reduces the power typically needed for haemostasis effect.

This work investigates the use of electronic tongues for environmental monitoring. Electronic tongues were based on arrays of potentiometric sensors plus a complex data processing by artificial neural networks and data transmission by radiofrequency. A first application, intended for a system simulating real conditions in surface water, performed a simultaneous monitoring of ammonium, potassium, sodium, chloride, and nitrate ions. The proposed system allowed us to assess the effect of natural biodegradation stages for these species. A second application was used to monitor concentrations of ammonium, potassium, and sodium in the ‘Ignacio Ramirez’ dam (Mexico). The electronic tongue used here allowed us to determine the content of the three cations in real water samples, although a high matrix effect was encountered for sodium determination. The implemented radio transmission worked robustly during all the experiments, thus demonstrating the viability of the proposed systems for automated remote applications.

In the study of voltammetric electronic tongues, a key point is the preprocessing of the departure information, the voltammograms which form the response of the sensor array, prior to classification or modeling with advanced chemometric tools. This work demonstrates the use of the discrete wavelet transform (DWT) for compacting these voltammograms prior to modeling. After compression, a system based on artificial neural networks (ANNs) was used for the quantification of the electroactive substances present, using the obtained wavelet decomposition coefficients as their inputs. The Daubechies wavelet of fourth order permitted an effective compression up to 16 coefficients, reducing the original dimension by ca. 10 times. The case studied is a mixture of three oxidizable amino acids:tryptophan, cysteine, and tyrosine. With the reduced information, one ANN per specie was trained using the Bayesian regularization algorithm. The proposed procedure was compared with the more conventional treatments of ...

A method for determining ammonium ion concentration from complex aqueous samples is presented in this work. It does not need to eliminate chemical interferences, mainly sodium and potassium, because an array of potentiometric sensors with intrinsic responses is used. The measurements taken from the array are processed with a multicomponent data treatment. This approach is already known as electronic tongue. Multivariable calibration was implemented with an artificial neural network, trained under the rules of the Bayesian regularization. The developed system has been applied to water samples from rivers and wastewaters with ammonium content in the range 1 × 10−4–5 × 10−2 mol L−1. Results are similar to those obtained with other reference methods.