Browsing by Subject "Radiofrequency"

Now showing 1 - 3 of 3
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    Histological changes in connective tissue of rat tails after bipolar radiofrequency treatment
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Bernal-Mañas, C.M.; Navarro, S.; Zuasti Elizondo, Adelina; Ferrer Cazorla, Concepción; Canteras Jordana, Manuel; García Collado, Angel Joaquín; Beltrán Frutos, Ester; Pastor García, Luis Miguel; Seco Rovira, Vicente; Facultades, Departamentos, Servicios y Escuelas::Departamentos de la UMU::Biología Celular e Histología
    Radiofrequency (RF) has been included in the techniques used in aesthetic surgery/medicine. To date, no studies have performed a histological assessment of changes in the tissue after application of bipolar radiofrequency (BRF) with low energy and frequency. The aim of this study was to examine changes that are produced in connective tissue, principally in the fibroblasts, following BRF treatment. Four groups of rats received a different number of RF sessions (1, 2, 3 and 5). The following parameters were determined: the number of fibroblasts/unit area (FA), the proliferation index (PI), the Heat shock Protein 47 index (HSPI) and the percentage of connective tissue (PC). For statistical analysis, two subgroups (A and B) were made for the variables FA, PI and PC, and another two subgroups (C and D) for the variable HSPI. Significant differences for FA, PI and PC were observed between subgroups A and B, FA and PI having higher values in A, while PC had higher values in B. The HSPI in subgroup C showed significantly higher values than in D. Low energy and frequency BRF led to an increase in the number, proliferation and biosynthetic activity of fibroblasts. The resulting stress suffered by fibroblasts as a result of heat may be associated with the phenomenon of hormesis
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    Modeling of radio frequency heating of packed fluid foods moving on a conveyor belt: A case study for tomato puree
    (Elsevier, 2023-05-20) Abea, Andrés; Kravets, Marina; Gou, Pera; Guàrdia, Dolors; Felipe, Xavier; Bañón, Sancho; Muñoz, Israel; Tecnología de Alimentos, Nutrición y Bromatología
    Computer simulation models were used to study radiofrequency heating of liquid foods moving on a conveyor belt between staggered-through field electrodes of non-uniform electric field distribution. Voltage across the electrodes was estimated using a finite-element model and a one-dimensional model, and these were utilized to simulate heating of tomato puree mixtures of varying dielectric and thermal properties, at various nominal voltages and electrode gaps. The experimental results for volume average temperatures showed good agreement with the outcome of both simulation models. Although the temperature profiles indicate a concentration of heat at the bottom and edges of the bottle, natural convection and the shape of the container helped mitigate heat localization. It was determined that, while simple models could provide accurate volume average temperatures,incorporating convectively enhanced conductivity was necessary to accurately predict temperature distribution. The heating rate was found to decrease with an increase in salt concentration.
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    Radiofrequency preserves histoarchitecture and enhances collagen synthesis in experimental tendon injury
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Akamatsu, Flavia Emi; Saleh, Samir Omar; Hojaij, Flávio; Real Martinez, Carlos Augusto; Andrade, Mauro; Teodoro, Walcy Rosolia; Jacomo, Alfredo Luiz
    We investigated the action of radiofrequency (RF) on the healing process after inducing experimental lesions of the Achilles tendon in rats. Wistar rats were surgically subjected to bilateral partial transverse sectioning of the Achilles tendon. The right tendon was treated with radiofrequency (RFT), whereas the left tendon served as a control (CT). On the third postoperative day, the rats were divided into three experimental groups consisting of ten rats each, which were treated with monopolar radiofrequency (Tonederm™) until they were sacrificed on the 7th, 14th or 28th days. The histological specimens were studied for inflammatory cell content, collagen types I and III, immunostaining and morphometry. Total collagen were biochemically analyzed and to evalute fibroblast and myofibroblast proliferation by vimentin and α-actin smooth muscle immunohistochemistry methods. Statistical analysis was performed using the Student's ttest, the sign test and the Kruskal-Wallis test to compare tendons treated with radiofrequency with the non-treated tendons (α=5%; α=10%). Larger amounts of collagen I with hydroxyproline content and myofibroblast cells were clearly evident within 7 days (p<0.05). No difference was observed in the inflammatory cell content between the groups. We found better collagen arrangement with RF administration across the entire time studied. Radiofrequency administration preserves histoarchitecture and enhances collagen synthesis during the initial phases of cicatrization, suggesting that the treatment can provide improved stiffness during the most vulnerable phases of tendon healing. Clinical studies may include RF among the therapeutic tools in tendinous lesion management.