Background: The modified Gompertz equation has been proposed to fit experimental data for direct current treated tumors when multiple-straight needle electrodes are individually inserted into the base perpendicular to the tumor long axis. The aim of this work is to evaluate the efficacy of direct current generated by multiple-electrode arrays on F3II mammary carcinoma that grow in the male and female BALB/c/Cenp mice, when multiple-straight needle electrodes and multiple-pairs of electrodes are inserted in the tumor. Methods: A longitudinal and retrospective preclinical study was carried out. Male and female BALB/c/Cenp mice, the modified Gompertz equation, intensities (2, 6 and 10 mA) and exposure times (10 and 20 min) of direct current, and three geometries of multiple-electrodes (one formed by collinear electrodes and two by pair-electrodes) were used. Tumor volume and mice weight were measured. In addition, the mean tumor doubling time, tumor regression percentage, tumor growth delay, direct current overall effectiveness and mice survival were calculated. Results: The greatest growth retardation, mean doubling time, regression percentage and growth delay of the primary F3II mammary carcinoma in male and female mice were observed when the geometry of multiple-pairs of electrodes was arranged in the tumor at 45, 135, 225 and 325 o and the longest exposure time. In addition, highest direct current overall effectiveness (above 66%) was observed for this EChT scheme. Conclusions: It is concluded that electrochemical therapy may be potentially addressed to highly aggressive and metastic primary F3II murine mammary carcinoma and the modified Gompertz equation may be used to fit data of this direct current treated carcinoma. Additionally, electrochemical therapy effectiveness depends on the exposure

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At present, sports injuries that occur during the practice of a sport or physical exercise are becoming more and more common, due to a series of predisposing factors that make an individual more susceptible to suffer these injuries. In Cuba there is a high prevalence of articular affections of knees and ankles, with a high prevalence in people older than 60 years; in the province of Santiago de Cuba 45% of the total number of consultations correspond to soft tissue injuries. One of the applications of the electromagnetic field is in the treatment of different pathologies of the osteomuscular system (Soma). The objective of this work lies in the design of a magnetic bed with permanent magnets, in analogy to a circular Halbach type configuration for the treatment of different diseases of the soma, which consists of three main parts: the magnetic system, which generates magnetic induction for therapeutic purposes, the opening and closing system of the magnetic system, which allows the radial variation of the magnetic system and the patient-support bed system, which allows the positioning of the patient in the treatment area. The principle of operation is that the therapist selects the induction of the magnetic field and the homogeneity of the magnetic field, depending on the pathology(s) to be treated, through a software that controls the movement of the opening and closing system of the magnetic system and the patient-bed support system, which is coupled to a stepper motor reducer that ensures a precise and accurate positioning of the sample (or patient) according to the area to be treated, which allows more than 80% effectiveness of the therapy with respect to conventional treatment.

At present, the application of magnetizers (magnetic conditioners) is increasingly booming, in the different branches of socioeconomic work such as Industry, Agriculture, and Medicine. In this work the calculation and design of a magnetizer is proposed; formed by equal permanent magnets type Halbach with rectangular shape, distributed and confined in a non-ferromagnetic structure, circular section in the form of a ring, consisting of an octagonal inner circle, with a magnetic field induction (25,7-42,8) mT and a homogeneity of magnetic field, in the volume of interest, of 1,5 x 10-2 ppm (in a sphere of radius of 0,025 m), in the center of the configuration lines are distributed transversally for different water flow capacities.