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Gene electrotransfer is a promising nonviral method for transferring genes into the cells. The method is based on electroporation and it has been proven to be successful in both in vivo and in vitro conditions. This phenomenon occurs when cells are exposed to electric field established by high and low voltage pulses. The first high voltage pulse results in a high level of cell permeabilization (permeabilization pulse), while the second low voltage pulse provides a driving force for transport of DNA into cells (electrophoretic pulse). The efficiency and successfulness of gene electrotransfer significantly depends on electrical devices in use. A voltage commutator presents one of the most important electrical components in bipolar or multi electrodes devices. Its main function is commutating high and low voltage pulses, which are delivered through the microelectrodes to the skin cells. Even though gene electrotransfer is based on electroporation, our previous voltage commutator for electroporation is appropriate for gene electrotransfer because of its slow switching between voltage pulses.

The aim of our study was to evaluate feasibility and therapeutic potential of electrotransfer of alone or combined with electrochemotherapy using cisplatin on two murine sarcomas with different status. Antitumor effectiveness of three consecutive electrotransfer of was more effective in wild-type LPB tumor than mutated SA-1 tumors, resulting in 21.4% of tumor cures in LPB tumor and 12.5% in SA-1 tumors. Pretreatment of tumors with electrotransfer of enhanced chemosensitivity of both tumor models treated by electrochemotherapy with cisplatin. After only one application of this treatment combination in LPB tumor model, specific tumor growth delay was prolonged in combined treatment group compared to electrotransfer of or electrochemotherapy with cisplatin alone, whereas in SA-1 tumors this treatment combination resulted in 31.6% of cured animals. Results of our study show that electrotransfer of alone or combined with electrochemotherapy is feasible and effective treatment of tumors. The combination of electrotransfer and electrochemotherapy after only one application resulted in complete regression of tumors.

Electrochemotherapy is a treatment that combines electroporation, i.e. application of electric pulses to the tumors, that induces under suitable conditions reversible permeabilization of cell membrane and administration of nonpermeant or poorly permeant chemotherapeutic drugs with intracellular targets, whose entry into the cells is facilitated by electroporation. In veterinary medicine, the predominant chemotherapeutic drug used in electrochemotherapy is cisplatin, followed by bleomycin. In this review, the results of the studies performed at the University of Ljubljana, Veterinary faculty are presented. Spontaneous tumors of different origin in dogs, cats and horses were treated with electrochemotherapy using either cisplatin or bleomycin. Different electroporation protocols were used and the results on antitumor effectiveness compared. The results demonstrated that electrochemotherapy is highly effective and safe local treatment regardless of tumor histology, chemotherapeutic drug or electroporation protocol used.

Electroporation is an effective alternative to viral methods to significantly improve DNA transfection after intradermal and topical delivery. We performed a series of in vivo experiments on rat skin using external plate electrodes. The experiments showed that skin layers below stratum corneum can be permeabilized in this way. In order to study the course of skin tissue permeabilization by means of electric pulses, a numerical model was built, with COMSOL Multiphysics, using the finite element method. The model is based on the tissue-electrode geometry and electric pulses from our in vivo experiments. We took into account the layered structure of skin and changes of its bulk electric properties during electroporation, as observed in the in vivo experiments. We were using tissue conductivity values found in literature and experimentally determined electric field threshold values needed for tissue permeabilization. The results obtained with the model were then compared to the in vivo results of gene transfection in rat skin and a good agreement was obtained.

The aim of this study was to determine the tumor blood flow modifying, and potential vascular disrupting effect of electrochemotherapy with bleomycin or cisplatin. Electrochemotherapy was performed by application of short intense electric pulses to the tumors after systemic administration of bleomycin or cisplatin. Evaluated were antitumor effectiveness of electrochemotherapy by tumor measurement, tumor blood flow modifying effect by Patent blue staining technique, and sensitivity of endothelial and tumor cells to the drugs and electrochemotherapy by clonogenicity assay. Electrochemotherapy was effective in treatment of SA-1 tumors in A/J mice resulting in substantial tumor growth delay and also tumor cures. Tumor blood flow reduction following electrochemotherapy correlated well with its antitumor effectiveness. Virtually complete shut down of the tumor blood flow was observed already at 24 h after electrochemotherapy with bleomycin whereas only 50% reduction was observed after electrochemotherapy with cisplatin.

Electrochemotherapy consists of chemotherapy followed by local application of electric pulses to the tumour to increase drug delivery into cells. Drug uptake can be increased by electroporation for only those drugs whose transport through the plasma membrane is impeded. Among many drugs that have been tested so far, only bleomycin and cisplatin found their way from preclinical testing to clinical trials. This local drug delivery approach is aimed at the treatment with palliative intent of cutaneous and subcutaneous tumour nodules of different histology. In clinical studies electrochemotherapy has proved to be highly effective and safe treatment approach for the treatment of cutaneous and subcutaneous tumour nodules. Treatment response for various tumours was 75% complete and 10% partial responses of the treated nodules. The main advantages of electrochemotherapy are its high effectiveness on tumours with different histology, simple application, minimal side effects and the possibility of effective repetitive treatment.

Electrochemotherapy has been established in preclinical and clinical studies as an effective therapy; however, the currently available technology for delivery of this treatment is limited to surface tumours and is reliant on macroelectrodes such as callipers and needles. Internal cancers are not currently amenable to electrochemotherapy. If it were possible to deliver permeabilising electric pulses to intraluminal gastrointestinal or urinary tract tumours endoscopically, or to intra-abdominal tumours via the laparoscopic approach, many cancers which are now deemed inoperable or which are unresponsive to conventional therapies would become accessible to electrochemotherapy. Tumour reduction or regression would be a feasible aim, facilitating the achievement of palliation of symptoms, improved quality of life, prolonged survival and ultimately cure.

Kishida has shown that in mice having B16 tumors, simultaneous administration of bleomycin and DNAc coding interleukin 12 (IL12) by electropermeabilization (electrochemo- immuno-geno-therapy : ECIGT) induces an immune response resulting in tumors volume decrease as well as decrease of metastatic lesions.

In the present study we explored the effect of longterm intervention protocol (3 w, 1 h/day) with sensory stimulation on neuroplastic changes in the human motor cortex. Interventions consisted of repetitive activation of afferent pathways of the right abductor policies brevis (APB) muscle with tendon vibration (TV) and transcutaneous electrical nerve stimulation (TENS). The representations of the hand (APB, ADM) and forearm (FCR, ECR) muscles were mapped using transcranial magnetic stimulation (TMS) before and after the 3 weeks of sensory intervention (TV and TENS) groups or after similar periods of daily active training of the APB or rest (control). Our observations showed a significant increase in motor cortical representation of all the four muscles (as measured by changes in the map size) for the TENS group. No such effects were observed in the tendon vibration group, active training group or the control group.

Functional Electrical Stimulation (FES) can be effective in assisting or restoring paralyzed motor functions caused by the spinal cord injury or the celebrovascular disease. The purpose of this study was to develop a control method of gait induced by FES. We had proposed a fuzzy control system based on cycle-to-cycle control for controlling hip, knee and ankle joints during the swing phase of FESinduced gait and evaluated it in computer simulation studies. In this report, the fuzzy controller was tested experimentally in controlling maximum knee extension angle stimulating the vastus muscles using surface electrodes with neurologically intact subjects. The fuzzy controller worked properly in regulating stimulation burst duration time and the maximum knee extension angle was controlled well. The experimental results suggested that the fuzzy controller would be practical in clinical applications for the control of FES-induced gait. However, it was also suggested that electrical stimulation with large burst duration time or muscle fatigue caused a change in muscle response.