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In this paper a numerical simulation analysis of a modified stent-based electrode is introduced to be used as a bipolar electrode for radio frequency ablation of tumours located in hollow organs. The purpose of this paper is to study the possibility of achieving a more regular volume of induced lesion with the presented electrode without imperilling the ductal organ where the tumour is located.

Three types of bipolar electrode configurations were considered, formed by two, three and five tubular segments. Numerical simulations were performed considering a tumour located in the bile duct, where two important blood vessels – the portal vein and the hepatic artery – have a significant impact due to the convective heat transfer caused by the blood flow (heat sink effect) which significantly affects the shape of lesion that is intended to induce in order to destroy the tumour.

The results obtained show that the five-segment electrode arrangement allows a regular volume for the induced lesion, independently of the different values of applied voltage considered.

The presented work introduces a numerical simulation analysis on a modified based-stent electrode previously studied. In this case, the electrode is configured so it can be used as a bipolar electrode, i.e., active and ground electrode are placed in the same device. Besides the results evinced by the obtained results, this kind of electrode avoids eventual skin burns that might occur due to the need of the return electrodes when monopolar electrodes are used.

The purpose of this paper is to propose a planning strategy for the radio frequency ablation (RFA) treatment of hepatic tumors. The goal is to give to the surgeon the opportunity of controlling the shape and the size of the treated volume and preserving the healthy tissues.

A FEM model of the human torso is built from radiographic and MRI scans of the patients, and then the RFA treatment “dynamically optimized” by controlling currents in multiple external electrodes, in such a way to drive currents in the desired regions, burning the tumor while trying to preserve healthy regions. A suitable cellular death model is considered in order to achieve an effective description of the biological modifications in the tumor volume.

A numerical method to plan the RFA treatment of hepatic tumors has been defined, aiming to preserve as much as possible healthy tissues.

The method depends on the knowledge of inner structure and properties of the patient's torso; while the structure of tissues can be determined by TAC or MRI scans, the physiological properties are much more uncertain.

The proposed approach allows optimized RFA treatments to be designed, allowing reduction of damage to healthy tissues deriving from application of the treatment.

The problem of optimal design of RFA treatments has been previously tackled in literature, but in this paper, dynamical optimization techniques and a cell death rate model have been included.

Cholangiocarcinoma is an adenocarcinoma of the bile ducts which drain bile from the liver into the small intestine. Unfortunately, most patients are diagnosed at an advanced stage of the disease with almost no chances for surgery, the only potentially curative treatment. As nitinol stents can be used to reduce stricture problems of the bile duct, these can be also considered as potential electrodes for hyperthermia treatments. Previous works show that, in fact, these metallic stents might be used as part of a feasible solution for delivering radiofrequency (RF) energy into a tumor located in a hollow organ to destroy the tumor tissue. However, the tissue lesion induced is not completely uniform due to convective heat transfer associated to the blood flow in the nearby vessels. The purpose of this paper is to study the use of saline solution for modifying the electrical conductivity of the tissue in order to obtain a more uniform lesion.

A numerical analysis using finite element method on a simplified model of the porta hepatis is performed. The tumor tissue is divided in three sections and simulations were performed considering a higher electrical conductivity in the middle section of the tumor, imitating the presence of a saline solution in this part of the tissue.

Results show that it is possible to obtain a more regular volume, by the way the tumor tissue is preferentially heated, although there are still some risks on exceeding the dimension of the bile duct.

This study presents the numerical analysis of a saline‐enhanced RF tissue thermoablation of a cholangiocarcinoma considering a stent‐based electrode. Results point to the possibility of obtaining a more regular volume of damaged tissue in order to heat and preferentially destroy the tumor tissue.

The purpose of this paper is to enable the correct selection of the radiofrequency thermal ablation (RFTA) process parameters for an individual patient by applying a computer modelling of RFTA.

The model is based on the X‐ray computer tomography images of the primary and metastatic hepatic tumours. The authors used the professional package of FLUX3D to generate the geometric models, assign materials properties, assign boundary conditions, perform mesh, carry out coupled thermo‐electromagnetic analysis and for post processing. The distribution of temperature and electric potential in the tissues of tumour and liver had been obtained as main results of the calculations.

The computational results show that the RFTA algorithm is effective in solving this practical problem. The computational results show that the selection of the type of electrodes used in the RFTA process is as important as the correct selection of the process parameters, i.e. voltage and frequency.

The paper presents a method to simulate the RFTA process and to select the process parameters.

Chronic ethanol consumption induces lipid peroxidation by increasing free radicals or reducing antioxidants and may increase damage to hepatic DNA. Tannins are polyphenolic metabolites present in various plants and one of their effects is antioxidant activity that reduces lipoperoxidation, as is the case for vitamin E. This paper aims to assess the role of tannic acid and vitamin E in lipid peroxidation and in DNA damage in rats receiving ethanol.

A total of 60 Wistar rats were divided into six groups: control+ethanol (0‐24hs), tannic acid+ethanol (0‐24 hs), and vitamin E+ethanol (0‐24 hs). The animals were sacrificed immediately (0 hour) or 24 hours after a period of four weeks of ethanol administration and the following measurements were made: plasma vitamin E and liver glutathione, thiobarbituric acid resistant substances, and α‐tocopherol. The comet test was also applied to hepatocytes.

Ethanol administration led to an increase in DNA damage (148.67±15.45 versus 172.63±18.94) during a period of 24 hours which was not detected in the groups receiving tannic acid or vitamin E. Steatosis was lower in the groups receiving tannic acid.

The paper highlights that antioxidant role of vitamin E and of tannic acid in biological systems submitted to oxidative stress should be reevaluated, especially regarding the protective role of tannic acid against hepatic steatosis.

Almost all people realise in a vague sort of way what inflation means in terms of the purchasing power of the pound ; that prices rise as its value goes down and that if this slowly declining trend is not arrested, then some sort of a crisis looms ahead.

The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution.

The present sensor consists in the spatial coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (polyvinylchloride [PVC]) and a plasticizer (dioctyl phthalate [DOP]). Several techniques have been used to characterize this sensor: the cyclic voltammetry, the electrochemical impedance spectroscopy and the optical microscopy. The sensibility, the selectivity and the kinetic study of a modified platinum electrode have been evaluated by cyclic voltammetry.

The obtained results reveal the possibility of a linear relationship between the current of reduction peaks and MG concentration. A linear response was obtained in a wide-concentration range that stretches from 10⁻⁵ to 10⁻¹³ mol L⁻¹, with a good correlation coefficient (0.976) and a good detection limit of 5.74 × 10⁻¹⁴ mol L⁻¹ (a signal-to-noise ratio of 3). In addition, the voltammetric response of modified electrode can be enhanced by adding a layer of Nafion membrane. Under this optimal condition, a linear relationship was obtained, with a correlation coefficient of 0.986 and a detection limit of 1.92 × 10⁻¹⁸ mol L⁻¹.

In the present research, a convenient, inexpensive and reproducible method for the detection of MG was developed. The developed sensor is capable of competing against the conventional techniques in terms of speed, stability and economy.

The use of physical 3D models has been used in the industry for a while, fulfilling the function of prototypes in the majority of cases where the designers, engineers and manufacturers optimize their designs before taking them into production. In recent years, there has been an increasing number of reports on the use of 3D models in medicine for preoperative planning. In some highly complex surgeries, the possibility of using printed models to previously perform operations can be determining in the success of the surgery. With the aim of providing new functionalities to an anatomical 3D-printed models, in this paper, a cost-effective manufacturing process has been developed. A set of tradition of traditional techniques have been combined with 3D printing to provide a maximum geometrical freedom to the process. By the use of an electroluminescent set of functional paints, the tumours and vessels of the anatomical printed model have been highlighted, providing to this models the possibility to increase its interaction with the surgeon. These set of techniques has been used to increase the value added to the reproduced element and reducing the costs of the printed model, thus making it more accessible.

Successfully case in where the use of a low-cost 3D-printed anatomical model was used as a tool for preoperative planning for a complex oncological surgery. The said model of a 70-year-old female patient with hepatic metastases was functionalized with the aim of increasing the interaction with the surgeons. The analysis of the construction process of the anatomical model based on the 3D printing as a tool for their use in the medical field has been made, as well as its cost.

The use of 3D printing in the construction of anatomical models as preoperative tools is relatively new; however, the functionalization of these tools by using conductive and electroluminescent materials with the aim of increasing the interaction with it by the surgeons is a novelty. And, based on the DIY principles, it offers a geographical limitlessness, reducing its cost without losing the added value.

The process based on 3D printing presented in this paper allows to reproduce low-cost anatomical models by following a simple sequence of steps. It can be done by people with low qualification anywhere with only access to the internet and with the local costs. The interaction of these models with the surgeon based on touch and sight is much higher, adding a very significant value it, without increasing its cost.

The purpose of this paper is to examine the potential effects of the intake of fermented milk containing the probiotic bacteria Lactobacilli spp. and Befidobacteria sp. as a supplementation for daily food and the possible prevention of hepatic lesions induced by the oral administration of a carcinogenic mutagen 3 amino‐I methyl‐5H‐pyrido (4, 3‐b) indole.

In total, 20 mice were divided into four groups. A control group was fed the murine pallet food for 30 days. Another three groups were given orally one dose of the toxic mutagen at the beginning of the experimental period and then fed the normal diet. At the 15th day, mice of the first group were dissected while the mice of the second group were given a second dose then continued feeding normal diet. Animals of the third group were given the second dose of the toxic mutagen and started feeding fermented milk for another 15 days. The quality of life was measured by specific strain count in stool, histopathological, histochemical changes of liver and count of lymphocytes were studied.

The variable count of Lac. sp. and Bif. sp. in stool of mice indicated that feeding these mice on the fermented milk repaired the slightly damaged areas and prevented the progressive damage effects of the toxic mutagen in these areas, while those which were severely damaged remained unrepaired. Moreover, the presented histochemical study recorded slight depletion in the total carbohydrate and total protein contents only in group C in comparison with controls.

The paper shows that the potential effect of fermented milk ingestion was capable of endorsing protective measures to hepatic tissue architecture and decreasing the toxic effect induced by mutagen administration.

This paper aims to study the feasibility of proposed method to focus the electroporation ablation by mean of multi-output multi-electrode system.

The proposed method has been developed based on a previously designed electroporation system, which has the capabilities to modify the electric field distribution in real time, and to estimate the impedance distribution. Taking into consideration the features of the system and biological tissues, the problem has been addressed in three phases: modeling, control system design and simulation testing. In the first phase, a finite element analysis model has been proposed to reproduce the electric field distribution within the hepatic tissue, based on the characteristics of the electroporation system. Then, a control strategy has been proposed with the goal of ensuring complete ablation while minimizing the affected volume of healthy tissue. Finally, to check the feasibility of the proposal, several representative cases have been simulated, and the results have been compared with those obtained by a traditional system.

The proposed method achieves the proposed goal, as part of a complex electroporation system designed to improve the targeting, effectiveness and control of electroporation treatments and serve to demonstrate the feasibility of developing new electroporation systems capable of adapting to changes in the preplanning of the treatment in real-time.

The work presents a thorough study of control method to multi-output multi-electrode electroporation system by mean of a rigorous numerical simulation.