Cell morphology impact on the set-up of electroporation protocols for in-suspension and adhered breast cancer cells.

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.

Instantaneous Position and Orientation of the Body Segments as an Arbitrary Object in 3D Space by Merging Gyroscope and Accelerometer Information / Posición y orientación instantánea de los segmentos corporales como un objeto arbitrario en el espacio 3D a través de la fusión de la información de acelerómetros y giroscopios

This work presents an algorithm to determine instantaneous orientation of an object in 3D space. The orientation was determined by using a Direction Cosine Matrix (DCM), performed by the combination of three consecutive rotations, around each to the main axes of the evaluated system, using quaternions. An inertial measurement unit (IMU), consisting of 3 axes gyroscope and 3 axes accelerometer was used in order to establish 2 coordinate systems; The first one describes object movement, by using gyroscope as a main source of information, relating the angular rate of change along time. The second defines a coordinate reference system, relating the acceleration of gravity to an inertial direction vector. A proportional integral (PI) feedback controller was used, which includes sensors information, eliminating offset, cancelling drift and improving the accuracy of the orientation. The proposed algorithm can be used for assessing both the position and orientation of the body segments which is very important in orthopedic, traumatology and rheumatology important for diagnosis, prognostic, therapeutic, research and as well as the design and fabrication of measuring devices used in surgical instrumentation, prostheses and ortheses. It is important to note that the developed system opens the opportunities to be implemented on ambulatory joint evaluation through a wearable system, due to the dimensions and requirements of the sensors.

El presente trabajo presenta un algoritmo para determinar la orientación instantánea de un objeto en el espacio 3D. La orientación fue determinada utilizando una matriz de cosenos directores (DCM) conformada por la combinación de 3 rotaciones consecutivas alrededor de cada uno de los ejes del sistema evaluado, utilizando cuaterniones. Una unidad inercial de medida (IMU) compuesta por un giroscopio de 3 ejes y un acelerómetro de 3 ejes fue utilizada con el objetivo de establecer 2 sistemas coordenados; Un sistema coordenado describiendo el movimiento del objeto, utilizando al giroscopio como fuente principal de información, estableciendo la relación de cambio con respecto al tiempo. Un sistema coordenado de referencia, relacionando la aceleración gravitacional a un vector inercial. Un control por retroalimentación proporcional integral (PI) fue utilizado con el objetivo de combinar la información de los sensores, eliminando las desviaciones por offset y deriva, mejorando la precisión en la orientación. Dadas sus características, el algoritmo propuesto permite su utilización en la evaluación de la posición y la orientación de los segmentos corporales, siendo de suma importancia en ortopedia, traumatología y reumatología para la determinación de diagnósticos, pronósticos terapéuticos e investigación así como el diseño y fabricación de dispositivos de medición, instrumentación quirúrgica, prótesis y ortesis. Cabe destacar que el sistema desarrollado abre oportunidades de ser implementado en el diseño de sistemas ambulatorios de evaluación de las articulaciones, mediante el uso de elementos transportables dadas las reducidas dimensiones y limitaciones de los sensores empleados.