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2.
Int J Biol Macromol ; 262(Pt 2): 130212, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38365142

RESUMEN

A novel electromagnetic heat extraction method was presented, whereby mandarin peels residue solution was located in a winding coil subjected to an oscillating magnetic field, and the pectin was extracted under appropriate conditions. Numerical relationships between applied magnetic field and induced electric field (IEF) in the extraction process were elaborated. The results showed that the induced current density, IEF and terminal temperature increased with increasing magnetic field. The maximum current density of 0.35 A/cm corresponds to the highest terminal temperature of 84.6 °C and IEF intensity of 26.6 V/cm. When magnetic field intensity was 1.39 T and the extraction time was 15 min, the maximum yield of pectin reached 9.16 %. In addition, all treatments impacted the ash content, protein content, water-holding capacity (WHC), and oil-holding capacity (OHC) of the obtained pectin. The pectin extracted by electromagnetic heat had the lowest DE value of 71.3 % with 126.55 kDa molecular weight, while the GalA content was at the highest level of 76.18 %. After different treatments, the composition of pectin monosaccharides changed, but there were slight differences in the composition of pectin polysaccharides. Moreover, the electromagnetic heat extracted pectin had light color and an obvious surface fragmentation of the peel residue.


Asunto(s)
Calor , Pectinas , Pectinas/química , Polisacáridos , Monosacáridos , Fenómenos Electromagnéticos
3.
Neuromodulation ; 27(1): 126-129, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37245139

RESUMEN

INTRODUCTION: Peripheral neuropathy has several causes, with diabetes being the most common. Conservative management may fail to control pain. Our study aimed at evaluating the use of peripheral nerve stimulation of the posterior tibial nerve for treating peripheral neuropathy. MATERIALS AND METHODS: This was an observational study of 15 patients who received peripheral nerve stimulation at the posterior tibial nerve to treat peripheral neuropathy. Outcomes measured were improvement of pain scores and Patient Global Impression of Change (PGIC) at 12 months compared with before the implant. RESULTS: Mean pain scores with the verbal rating scale were 3 ± 1.8 at >12 months compared with 8.6 ± 1.2 at baseline, a reduction of 65% (p < 0.001). Median satisfaction with the PGIC at >12 months was 7 of 7, with most subjects reporting a 6 (better) or a 7 (a great deal better). CONCLUSION: Peripheral nerve stimulation of the posterior tibial nerve can be a safe and effective modality for treating chronic pain symptoms related to peripheral neuropathy of the foot.


Asunto(s)
Dolor Crónico , Enfermedades del Sistema Nervioso Periférico , Estimulación Eléctrica Transcutánea del Nervio , Humanos , Dolor Crónico/terapia , Nervio Tibial , Fenómenos Electromagnéticos
4.
Environ Sci Pollut Res Int ; 30(48): 106083-106098, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37723396

RESUMEN

The impact of climate change on water resource availability and soil quality is more and more emphasized under the Mediterranean basin, mostly characterized by drought and extreme weather conditions. The present study aims to investigate how electromagnetic induction technique and soil mapping combined with crop yield data can be used to optimize phosphorus (P) use efficiency by chickpea crop under drip fertigation system. The study was carried out on a 2.5-ha agricultural plot and the agronomic experiments in two growing cycles of chickpea crop. Soil spatial variability was first assessed by the measurement of soil apparent electrical conductivity (ECa) using the CMD Mini-Explorer sensor, and then, soil physicochemical properties were evaluated based on an oriented soil sampling scheme to explore other soil spatial variabilities influencing chickpea yield and quality. Data from the first agronomic experiment were used in geostatistical, multiple linear regression (MLR), and fuzzy c-means unsupervised classification algorithms to properly identify P drip fertigation management zones (MZs). Results from the Person's correlation analysis revealed that chickpea grain yield was more influenced by soil ECa (r = - 0.56), pH (r = - 0.84), ECe (r = - 0.6), P content (r = 0.72), and calcium (Ca) content (r = - 0.83). The proposed MLR-based model to predict chickpea grain yield showed good performances with a normalized root mean square error (NRMSE) of 0.11% and a coefficient of determination (R2) equal to 0.69. The identified MZs were verified by the one-way variance analysis for the studied soil and plant attributes, revealing that the first MZ1 presents a high grain yield, high soil P content, and low ECa. The low fertility MZ2 located in the south part of the studied site presented a low chickpea grain yield due to the low P content and the high ECa. Moreover, the application of P-variable rate fertigation regimes in the second field experiment significantly improved P use efficiency, chickpea grain yield, seed quality, and farmer income by 18%, 12%, 9%, and 136 $/ha, respectively, as compared to the conventional drip fertigation practices. The approach proposed in this study can greatly contribute to optimizing agro-input use efficiency under drip fertigation system, thereby improving farmers' incomes, preserving the ecosystem, and ensuring sustainable cropping systems in the Mediterranean climate.


Asunto(s)
Cicer , Suelo , Humanos , Suelo/química , Fósforo/análisis , Ecosistema , Agricultura , Fenómenos Electromagnéticos , Grano Comestible/química
5.
J Neuroeng Rehabil ; 20(1): 129, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37752553

RESUMEN

PURPOSE: Tremor is one of the key characteristics of Parkinson's disease (PD), leading to physical disabilities and often showing limited responses to pharmacological treatments. To suppress tremors in PD patients, several types of non-invasive and non-pharmacological methods have been proposed so far. In the current systematic review, three electromagnetic-based radiation strategies including electrical stimulation, magnetic stimulation, and light stimulation methods were reviewed and compared. METHODS: Major databases were searched to retrieve eligible studies. For the meta-analysis, a random-effect Bayesian framework was used. Also, heterogeneity between studies was assessed using I2 statistic, prediction interval, and tau2. Publication bias was assessed using funnel plot, and the effectiveness of methods for reducing tremor was compared using network Bayesian meta-analysis. RESULTS AND CONCLUSION: Thirty-one studies were found for qualitative analysis, and 16 studies were found for quantitative synthesis. Based on the suppression ratio, methods can be ordered as electrical stimulation, light therapy, and magnetic stimulation. Furthermore, the results showed that electrical and magnetic stimulation were more effective for tremor suppression at early stages of PD, while light therapy was found to be more effective during the later stages of PD.


Asunto(s)
Terapia por Estimulación Eléctrica , Enfermedad de Parkinson , Humanos , Teorema de Bayes , Terapia por Estimulación Eléctrica/efectos adversos , Fenómenos Electromagnéticos , Radiación Electromagnética , Fenómenos Magnéticos , Enfermedad de Parkinson/radioterapia , Temblor/etiología , Temblor/terapia , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto
6.
Europace ; 25(7)2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37487241

RESUMEN

BACKGROUND: Transcutaneous electrical nerve stimulation (TENS) is an established method for pain relief. But electrical TENS currents are also a source of electromagnetic interference (EMI). Thus, TENS is considered to be contraindicated in implantable cardioverter-defibrillator (ICD) patients. However, data might be outdated due to considerable advances in ICD and cardiac resynchronization therapy (CRT) filtering and noise protection algorithm technologies. The aim of this pilot safety study was to re-evaluate the safety of TENS in patients with modern ICDs. METHODS AND RESULTS: One hundred and seven patients equipped with 55 different models of ICD/CRT with defibrillators from 4 manufacturers underwent a standardized test protocol including TENS at the cervical spine and the thorax, at 2 stimulation modes-high-frequency TENS (80 Hz) and burst-mode TENS (2 Hz). Potential interference monitoring included continuous documentation of ECG Lead II, intracardiac electrograms and the marker channel. Electromagnetic interference was detected in 17 of 107 patients (15.9%). Most frequent were: interpretations as a premature ventricular beats (VS/S) in 15 patients (14%), noise reversion in 5 (4.6%) which resulted in temporary asynchronous pacing in 3 (2.8%), interpretation as ventricular tachycardia/ventricular fibrillation in 2 (1.9%), and premature atrial beat in 2 (1.9%) patients. Electromagnetic interference occurrence was influenced by position (chest, P < 0.01), higher current intensity (P < 0.01), and manufacturer (P = 0.012). CONCLUSION: Overall, only intermittent and minor EMI were detected. Prior to the use of TENS in patients with ICDs, they should undergo testing under the supervision of a cardiac device specialist.


Asunto(s)
Desfibriladores Implantables , Estimulación Eléctrica Transcutánea del Nervio , Humanos , Manejo del Dolor , Algoritmos , Fibrilación Ventricular , Fenómenos Electromagnéticos
7.
ACS Appl Mater Interfaces ; 15(19): 23653-23661, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37155934

RESUMEN

An energy-saving scheme that can simultaneously realize electromagnetic interference (EMI) shielding, passive solar radiative heating, and active Joule heating in a single wearable device is still a huge challenge. Here, by combining the unique properties of Ti3C2Tx MXene and biocompatible cellulose nanofibers (CNFs), a flexible, degradable, and antibacterial multifunctional Ti3C2Tx/CNF paper (∼0.6 Ω/sq) is constructed through a facile vacuum filtration strategy. The resultant device not only exhibits an admirable EMI shielding effectiveness of ∼48.5 dB at the X-band and a superior heating property including dual-driven electrothermal and photothermal conversion without energy but also possesses wide temperature range regulation and long-time stability. More impressively, both high antibacterial efficiency (toward both gram-positive and gram-negative bacteria) and good degradability with low-concentration hydrogen peroxide solution can also be achieved in Ti3C2Tx/CNF papers. This study provides a promising platform for practical applications of multifunctional Ti3C2Tx/CNFs in EMI shielding, thermotherapy, heat preservation, and antibacterial protection in harsh environments, satisfying the demands for energy-saving, environmentally friendly, and sustainable development.


Asunto(s)
Antibacterianos , Bacterias Gramnegativas , Antibacterianos/farmacología , Bacterias Grampositivas , Titanio , Celulosa , Fenómenos Electromagnéticos
8.
Biomed J ; 46(1): 30-40, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36496151

RESUMEN

There are a growing number of studies investigating how grounding (earthing) the body may benefit biological performance and aid the treatment of non-communicable diseases. Research also indicates how biological grounding initiatives can sometimes be compromised, or inappropriate, and the need to take additional factors into account as potential contributory factors, or confounders, to expected results. It is proposed that expanding electromagnetic hygiene measures beyond biological grounding alone may help reduce spread of communicable diseases, incidence of respiratory conditions, neurodegenerative disease and all-cause mortality. Identifying potential synergies that exist could enable multilevel interventions to further increase the efficacy of measures. It is hoped that this review will help act as a catalyst to inspire and inform multi-disciplinary research within these topic areas, best practices and policies to help drive medical innovation, reduce health burdens, improve bioelectromagnetic-based therapies, and influence the general design of the built environment and next-generation technologies.


Asunto(s)
Enfermedades Neurodegenerativas , Humanos , Fenómenos Electromagnéticos , Higiene
9.
Protoplasma ; 260(1): 209-224, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35546647

RESUMEN

Unprecedented growth in the communication sector and expanded usage of the number of wireless devices in the past few decades have resulted in a tremendous increase in emissions of non-ionizing electromagnetic radiations (EMRs) in the environment. The widespread EMRs have induced many significant changes in biological systems leading to oxidative stress as well as DNA damage. Considering this, the present study was planned to study the effects of EMRs at 900 MHz frequency with the power density of 10.0 dBm (0.01 W) at variable exposure periods (0.5 h, 1 h, 2 h, 4 h, and 8 h per day for 7 days) on percentage germination, morphological characteristics, protein content, lipid peroxidation in terms of malondialdehyde content (MDA), and antioxidant defense system of Trigonella foenum-graecum test system. The genotoxicity was also evaluated using similar conditions. It was observed that EMRs significantly decreased the germination percentage at an exposure time of 4 h and 8 h. Fresh weight and dry weight of root and shoot did not show significant variations, while the root and shoot length have shown significant variations for 4 h and 8 h exposure period. Further, EMRs enhanced MDA indicating lipid peroxidation. In response to exposure of EMRs, there was a significant up-regulation in the activities of enzymes such as ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione-S-transferase (GST), guaiacol peroxidase (POD), and glutathione reductase (GR) in the roots and shoots of Trigonella-foenum graecum. The genotoxicity study showed the induction of chromosomal aberrations in root tip cells of the Trigonella foenum-graecum test system. The present study revealed the induction of oxidative stress and genotoxicity of EMRs exposure in the test system.


Asunto(s)
Trigonella , Trigonella/metabolismo , Estrés Oxidativo , Antioxidantes/metabolismo , Extractos Vegetales/farmacología , Daño del ADN , Fenómenos Electromagnéticos
10.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36232421

RESUMEN

The role of signalling in initiating and perpetuating effects triggered by deposition of ionising radiation energy in parts of a system is very clear. Less clear are the very early steps involved in converting energy to chemical and biological effects in non-targeted parts of the system. The paper aims to present a new model, which could aid our understanding of the role of low dose effects in determining ultimate disease outcomes. We propose a key role for electromagnetic signals resulting from physico-chemical processes such as excitation decay, and acoustic waves. These lead to the initiation of damage response pathways such as elevation of reactive oxygen species and membrane associated changes in key ion channels. Critically, these signalling pathways allow coordination of responses across system levels. For example, depending on how these perturbations are transduced, adverse or beneficial outcomes may predominate. We suggest that by appreciating the importance of signalling and communication between multiple levels of organisation, a unified theory could emerge. This would allow the development of models incorporating time, space and system level to position data in appropriate areas of a multidimensional domain. We propose the use of the term "infosome" to capture the nature of radiation-induced communication systems which include physical as well as chemical signals. We have named our model "the variable response model" or "VRM" which allows for multiple outcomes following exposure to low doses or to signals from low dose irradiated cells, tissues or organisms. We suggest that the use of both dose and infosome in radiation protection might open up new conceptual avenues that could allow intrinsic uncertainty to be embraced within a holistic protection framework.


Asunto(s)
Efecto Espectador , Traumatismos por Radiación , Efecto Espectador/efectos de la radiación , Conservación de los Recursos Naturales , Relación Dosis-Respuesta en la Radiación , Fenómenos Electromagnéticos , Humanos , Radiación Ionizante , Especies Reactivas de Oxígeno/metabolismo
12.
Int J Hyperthermia ; 39(1): 987-997, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35876086

RESUMEN

PURPOSE: Tumor perfusion is considered to be the principal factor determining the build-up of therapeutically effective thermal fields. This assumes that malignancies have lower perfusions than their homologous tissues. This assumption, however, ignores the fact that several tumor types have higher perfusions than their healthy counterparts. Additionally, flow changes upon hyperthermia (39-43 °C) are non-predictable and extremely heterogeneous. Therefore, modeling temperature distribution further requires a more robust parameter, different in malignancies and healthy tissues, i.e., water content (Cw), which highly determines thermal properties upon electromagnetic irradiation. METHOD: Systematic literature reviews of Cw and specific heat capacities (cp) were conducted up to 28 February 2022, providing an updated, comprehensive data overview based on original manuscripts, reviews and databases. RESULTS: Cw- and cp-values of cancers and their corresponding healthy tissues are presented. Strong correlations between these two parameters are described. In general, malignant tumors have distinctly higher Cw values than their homologous tissues. With increasing Cw in low-water-content normal tissues (<70 wt.%), cp rises exponentially from 1.5 to 3.3 J·g-1·K-1. In high-water-content normal tissues (≥70 wt.%), cp increases linearly from 3.5 to 3.8 J·g-1·K-1. In malignant tumors (>80 wt.%), cp rises linearly from 3.6 to 3.9 J·g-1·K-1. Cancers contain up to 27% more water than their tissues of origin and must be considered as 'high-capacitance-tissues'. CONCLUSIONS: Hyperhydration of cancers result in higher cp-values, causing cancers to be better heat reservoirs than corresponding normal tissues upon electromagnetic irradiation. Reliable, tissue-/cancer-specific cp values must be considered when modeling temperature distributions in hyperthermic treatment.


Asunto(s)
Hipertermia Inducida , Neoplasias , Fenómenos Electromagnéticos , Calor , Humanos , Neoplasias/radioterapia , Agua
13.
Bioelectromagnetics ; 43(5): 336-346, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35544783

RESUMEN

A large number of studies on the biological effects of microwaves are carried out using rodents and cells, but the conditions are difficult to control, and the irradiation period is short; the results obtained have always been controversial and difficult to reproduce. In this study, we expose nematodes to an electromagnetic environment for a long-term and multigeneration period to explore the possible biological effects. Wild-type N2 strains of Caenorhabditis elegans are exposed to 9.4 GHz microwaves at a specific adsorption rate of 4 W/kg for 10 h per day from L1 larvae to adults. Then, adult worms are washed off, and the laid eggs are kept to hatch L1 larvae, which are continuously exposed to microwaves until passing through 20 generations. The worms of the 10th, 15th, and 20th generations are collected for index detection. Interestingly, we found that the fecundity of C. elegans decreased significantly in the exposed group from the 15th generation. At the same time, we found that the growth of C. elegans decreased, motility decreased, and oxidative stress occurred in the exposed group from the 10th generation, which may play roles in the decreased spawning in worms. We preliminarily believe that the microwave energy received by worms leads to oxidative stress, which causes a decrease in the spawning rate, and the underlying mechanism needs to be further studied. © 2022 Bioelectromagnetics Society.


Asunto(s)
Caenorhabditis elegans , Microondas , Animales , Caenorhabditis elegans/efectos de la radiación , Fenómenos Electromagnéticos
14.
Bioelectromagnetics ; 43(4): 217, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35445747
15.
Molecules ; 27(6)2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35335204

RESUMEN

To transform tall goldenrods, which are invasive alien plant that destroy the ecosystem of South Korea, into useful materials, cellulose fibers isolated from tall goldenrods are applied as EMI shielding materials in this study. The obtained cellulose fibers were blended with CNTs, which were used as additives, to improve the electrical conductivity. TGCF/CNT papers prepared using a facile paper manufacturing process with various weight percent ratios and thickness were carbonized at high temperatures and investigated as EMI shielding materials. The increase in the carbonization temperature, thickness, and CNT content enhanced the electrical conductivity and EMI SE of TGCF/CNT carbon papers. TGCF/CNT-15 papers, with approximately 4.5 mm of thickness, carbonized at 1300 °C exhibited the highest electrical conductivity of 6.35 S cm-1, indicating an EMI SE of approximately 62 dB at 1.6 GHz of the low frequency band. Additionally, the obtained TGCF/CNT carbon papers were flexible and could be bent and wound without breaking.


Asunto(s)
Nanotubos de Carbono , Solidago , Celulosa , Ecosistema , Fenómenos Electromagnéticos
16.
Plast Reconstr Surg ; 149(5): 893e-900e, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35259147

RESUMEN

BACKGROUND: Radiofrequency-based and high-intensity focused electromagnetic (HIFEM)-based devices have proved effective and safe for abdominal body shaping. Radiofrequency is known to reduce adipose tissue, whereas HIFEM treatment is effective for muscle definition. The authors investigated the efficacy of a novel device delivering synchronized radiofrequency and HIFEM treatment simultaneously for abdominal toning and fat reduction. METHODS: Seventy-two patients were enrolled and randomly divided into active (n = 48; age, 45.5 ± 13.0 years) and sham groups (n = 24; age, 44.6 ± 12.3 years). Both groups received three treatments on the abdomen once a week. The intensity in the active group was set to maximum tolerable level; in the sham group, the intensities were set to 5 percent. Ultrasound images were taken before treatment and at 1, 3, and 6 months after treatment to examine changes in subcutaneous fat and rectus abdominis muscle thickness. Digital photographs were taken, and satisfaction and therapy comfort were assessed. RESULTS: Ultrasound images of the active group at 1 month showed significant (p < 0.05) reduction in adipose tissue thickness by 20.5 percent (4.8 ± 2.6 mm), whereas rectus abdominis muscle thickness increased by 21.5 percent (2.0 ± 0.8 mm). Results at 3 months improved to 28.3 percent (7.6 ± 3.7 mm) and 24.2 percent (2.3 ± 0.9 mm), respectively. Improvements were maintained at 6 months after treatment in the active group, whereas the sham group showed no significant changes. Treatments were found to be comfortable. The active group showed higher satisfaction with outcomes. CONCLUSION: Active treatment utilizing simultaneous application of radiofrequency and HIFEM therapy resulted in a significant increase in rectus abdominis thickness and subcutaneous fat reduction, exceeding previously published results for separate HIFEM and radiofrequency treatments. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.


Asunto(s)
Contorneado Corporal , Magnetoterapia , Adulto , Contorneado Corporal/métodos , Fenómenos Electromagnéticos , Calefacción , Humanos , Magnetoterapia/métodos , Persona de Mediana Edad , Grasa Subcutánea
17.
BMC Neurol ; 22(1): 48, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35139806

RESUMEN

BACKGROUND: By definition, the background EEG is normal in juvenile myoclonic epilepsy (JME) patients and not accompanied by other developmental and cognitive problems. However, some recent studies using quantitative EEG (qEEG) reported abnormal changes in the background activity. QEEG investigation in patients undergoing anticonvulsant treatment might be a useful approach to explore the electrophysiology and anticonvulsant effects in JME. METHODS: We investigated background EEG activity changes in patients undergoing valproic acid (VPA) treatment using qEEG analysis in a distributed source model. In 17 children with JME, non-parametric statistical analysis using standardized low-resolution brain electromagnetic tomography was performed to compare the current density distribution of four frequency bands (delta, theta, alpha, and beta) between untreated and treated conditions. RESULTS: VPA reduced background EEG activity in the low-frequency (delta-theta) bands across the frontal, parieto-occipital, and limbic lobes (threshold log-F-ratio = ±1.414, p < 0.05; threshold log-F-ratio= ±1.465, p < 0.01). In the delta band, comparative analysis revealed significant current density differences in the occipital, parietal, and limbic lobes. In the theta band, the analysis revealed significant differences in the frontal, occipital, and limbic lobes. The maximal difference was found in the delta band in the cuneus of the left occipital lobe (log-F-ratio = -1.840) and the theta band in the medial frontal gyrus of the left frontal lobe (log-F-ratio = -1.610). CONCLUSIONS: This study demonstrated the anticonvulsant effects on the neural networks involved in JME. In addition, these findings suggested the focal features and the possibility of functional deficits in patients with JME.


Asunto(s)
Epilepsia Mioclónica Juvenil , Ácido Valproico , Encéfalo/diagnóstico por imagen , Niño , Electroencefalografía , Fenómenos Electromagnéticos , Lóbulo Frontal , Humanos , Epilepsia Mioclónica Juvenil/tratamiento farmacológico , Tomografía , Ácido Valproico/uso terapéutico
18.
Sensors (Basel) ; 22(4)2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35214230

RESUMEN

The combination of interstitial hyperthermia treatment (IHT) with high dose rate brachytherapy (HDR-BT) can improve clinical outcomes since it highly enhances the efficiency of cell kill, especially when applied simultaneously. Therefore, we have developed the ThermoBrachy applicators. To effectively apply optimal targeted IHT, treatment planning is considered essential. However, treatment planning in IHT is rarely applied as it is regarded as difficult to accurately calculate the deposited energy in the tissue in a short enough time for clinical practice. In this study, we investigated various time-efficient methods for fast computation of the electromagnetic (EM) energy deposition resulting from the ThermoBrachy applicators. Initially, we investigated the use of an electro-quasistatic solver. Next, we extended our investigation to the application of geometric simplifications. Furthermore, we investigated the validity of the superpositioning principle, which can enable adaptive treatment plan optimization without the need for continuous recomputation of the EM field. Finally, we evaluated the accuracy of the methods by comparing them to the golden standard Finite-Difference Time-Domain calculation method using gamma-index analysis. The simplifications considerably reduced the computation time needed, improving from >12 h to a few seconds. All investigated methods showed excellent agreement with the golden standard by showing a >99% passing rate with 1%/0.5 mm Dose Difference and Distance-to-Agreement criteria. These results allow the proposed electromagnetic simulation method to be used for fast and accurate adaptive treatment planning.


Asunto(s)
Braquiterapia , Hipertermia Inducida , Braquiterapia/métodos , Simulación por Computador , Fenómenos Electromagnéticos , Hipertermia Inducida/métodos , Dosificación Radioterapéutica
19.
Nanoscale ; 14(4): 1187-1194, 2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35005765

RESUMEN

Browning of white adipose tissue (WAT) is becoming an attractive therapeutic target for obesity. Great efforts have been made to develop effective approaches to induce browning. Unfortunately, the current methods suffer from a series of disadvantages, such as low efficiency, unsatisfactory stability, and side effects. Herein, we report a new approach to induce browning of 3T3-L1 white adipocytes based on electromagnetic induction heating (EIH) hyperthermia. In particular, adipocyte-targeting aptamer modified gold nanoclusters (Apt-AuNCs) were employed as the mediators of EIH. Apt-AuNCs had good biocompatibility and excellent targeting performance with white adipocytes. After Apt-AuNCs/EIH treatment, adipocytes with characteristic multilocular and small lipid droplets increased, and the content of triglycerides reduced effectively. Apt-AuNCs/EIH treatment also significantly increased the mitochondrial activity in adipocytes. Meanwhile, the mRNA levels of key genes that are involved in browning, for example UCP1, PRDM16, PPARγ, and PGC-1α, were upregulated. Finally, the induction mechanism of Apt-AuNCs/EIH on browning of white adipocytes was explained by the synergistic effects of EIH hyperthermia and pharmacological action of AuNCs. To the best of our knowledge, this is the first attempt on induction of browning by metal nanocluster-mediated EIH hyperthermia, thus providing an interesting and efficient channel for obesity treatment.


Asunto(s)
Adipocitos Blancos , Hipertermia Inducida , Células 3T3-L1 , Animales , Fenómenos Electromagnéticos , Oro , Calefacción , Ratones
20.
Bioelectromagnetics ; 43(1): 5-13, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34962293

RESUMEN

Because of the extensive application of electromagnetic technology, its health impact on humans has attracted widespread attention. Due to the lack of a model organism with a stable response to electromagnetic waves, the research conclusions on the biological effects of electromagnetic waves have been vague. Therefore, the aim of this study was to investigate the effects of irradiation by pulsed 9.4 GHz high-power microwaves with a peak power density of 2126 W/cm2 using Caenorhabditis elegans. The development, movement, egg production, ROS, and lifespan of C. elegans were detected at different times after irradiation with different repetitive frequencies of 10, 20, and 50 Hz for 30 min. The results indicated that no obvious changes in basic life indices were induced compared with the sham radiation group, but the survival rate of positive control was significantly decreased compared with other groups, which is of interest for microwave protection research based on C. elegans and provides data for updating safety standards with respect to pulsed high-peak power microwave. © 2021 Bioelectromagnetics Society.


Asunto(s)
Caenorhabditis elegans , Microondas , Animales , Fenómenos Electromagnéticos , Humanos
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