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1.
Front Bioeng Biotechnol ; 12: 1432189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161353

RESUMEN

Magnetic induction hyperthermia (MIH), is a technique that has developed rapidly in recent years in the field of tumor thermotherapy. It implants a magnetic heating medium (millimeter-sized heat seeds, micron-sized magnetic particles and nanometer-sized magnetic fluids, etc.) inside the tumor. The material heats up under the induction of an external alternating magnetic field (100-500 kHz), which causes a high temperature zone to rapidly form in the local biological tissues and induces apoptosis in tumor cells. Magnetic induction hyperthermia has the advantages of high safety, strong targeting, repeatable treatment, and the size of the incision during treatment is negligible compared to surgical resection, and is currently used in clinical treatment. However, the millimeter-scale heat seed heating that is typically used in treatments can result in uneven temperatures within the tissue. Common MIH heating devices are bulky and complex in design, and are not easy for medical staff to get their hands on, which are issues that limit the diffusion of MIH. In this view, this paper will discuss the basic theoretical research on MIH and the progress of MIH-related technologies, with a focus on the latest research and development results and research hotspots of nanoscale ferromagnetic media and magnetic heat therapy devices, as well as the validation results and therapeutic efficacy of the new MIH technology on animal experiments and clinical trials. In this paper, it is found that induction heating using magnetic nanoparticles improves the uniformity of the temperature field, and the magneto-thermal properties of nanoscale ferromagnetic materials are significantly improved. The heating device was miniaturized to simplify the operation steps, while the focusing of the magnetic field was locally enhanced. However, there are fewer studies on the biotoxicity aspects of nanomedicines, and the localized alternating magnetic field uniformity used for heating and the safety of the alternating magnetic field after irradiation of the human body have not been sufficiently discussed. Ultimately, the purpose of this paper is to advance research related to magnetic induction thermotherapy that can be applied in clinical treatment.

2.
Radiat Prot Dosimetry ; 200(14): 1329-1338, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39016042

RESUMEN

The electromagnetic environment of a railway station is composed of electrical, magnetic, and electromagnetic fields, which are generated by various sources such as traction current, voltage, pantograph-catenary arc, locomotive braking, wheel-rail rolling arc, and communication systems. However, there is public growing concern among the public about the potential negative human health effects of this electromagnetic environment. To analyze the distribution of electromagnetic fields in human tissues, electromagnetic simulation software is used to create a model that includes six track contact wires and four waiting passengers on three platforms. This model is used to analyze the magnetic field environment created by high currents in the contact wires of a multi-track high-speed railway station. By varying the loads on different contact wires, the distribution of electric field and magnetic flux density within human tissues of waiting passengers on different platforms is studied using this model. When the track is unoccupied, the calculation results show that the maximum values of the electric field and magnetic flux density of the passenger's human body tissue at the blind way on the platform and 1 m of the blind way are 17.6 mV m-1 and 52.7 µT, respectively. These values increase by 9.28 mV m-1 and 16.4 µT compared to when the track is occupied. When more contact wires are loaded with currents, the electric field mode and magnetic flux density mode of human tissues increase at the same position on the platform. Specifically, when the contact wires of six tracks are loaded with current at the same time, the maximum values of the electric field mode and magnetic flux density mode of the waiting passengers' human tissues at the blind way on different platforms are 29.6 mV m-1 and 88.1 µT, respectively. These maximum values are lower than the public electromagnetic exposure limits that are designated by the International Commission on Non-Ionizing Radiation Protection guidelines. The research results demonstrate that the magnetic field environment generated by the current in the contact wires of a railway station with six tracks does not pose a health risk to human tissues of passengers waiting at the blind way and 1 m of the blind way on the platform. These findings can provide valuable data reference for the formulation of relevant standards for the design of electrified rail transit, as well as the suppression of electromagnetic interference and protection of human bioelectromagnetism.


Asunto(s)
Simulación por Computador , Campos Electromagnéticos , Exposición a Riesgos Ambientales , Humanos , Exposición a Riesgos Ambientales/análisis , Vías Férreas , Monitoreo de Radiación/métodos , Dosis de Radiación
3.
Bioengineering (Basel) ; 11(7)2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39061776

RESUMEN

In recent years, the progressively escalating incidence and exceptionally high fatality rate of cutaneous melanoma have drawn the attention of numerous scholars. Magnetic induction hyperthermia, as an efficacious tumor treatment modality, has been promoted and applied in the therapy of some tumors. In this paper, the melanoma atop the mice's heads was chosen as the research subject, and a magnetic induction hyperthermia approach based on Helmholtz coils as the magnetic field excitation was investigated and designed. The influence of the electromagnetic field and thermal field on organisms was addressed through modeling by COMSOL simulation software. The results showed that the maximum values of induced electric field and magnetic induction strength in mouse tumor tissues were 63.1 V/m and 8.5621 mT, respectively, which reached the threshold value of magnetic field strength required for magnetic induction hyperthermia. The maxima of the induced electric field and magnetic induction intensity in brain tissues are, respectively, 35.828 V/m and 8.57 mT. Approximately 93% of the tumor tissue can reach 42 °C, and the maximum temperature is 44.2 °C. Within this temperature range, a large quantity of tumor cells can be successfully induced to undergo apoptosis without harming normal cells, and the therapeutic effect is favorable.

4.
Sensors (Basel) ; 24(13)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39001174

RESUMEN

The number of individuals wearing cardiac pacemakers is gradually increasing as the population ages and cardiovascular disease becomes highly prevalent. The safety of pacemaker wearers is of significant concern because they must ensure that the device properly functions in various life scenarios. Electric vehicles have become one of the most frequently used travel tools due to the gradual promotion of low-carbon travel policies in various countries. The electromagnetic environment inside the vehicle is highly complex during driving due to the integration of numerous high-power electrical devices inside the vehicle. In order to ensure the safety of this group, the paper takes passengers wearing cardiac pacemakers as the object and the electric vehicle drive motors as the exposure source. Calculation models, with the vehicle body, human body, heart, and cardiac pacemaker, are built. The induced electric field, specific absorption rate, and temperature changes in the passenger's body and heart are calculated by using the finite element method. Results show that the maximum value of the induced electric field of the passenger occurs at the ankle of the body, which is 60.3 mV/m. The value of the induced electric field of the heart is greater than that of the human trunk, and the maximum value (283 mV/m) is around the pacemaker electrode. The maximum specific absorption rate of the human body is 1.08 × 10-6 W/kg, and that of heart positioned near the electrode is 2.76 × 10-5 W/kg. In addition, the maximum temperature increases of the human torso, heart, and pacemaker are 0.16 × 10-5 °C, 0.4 × 10-6 °C, and 0.44 × 10-6 °C within 30 min, respectively. Accordingly, the induced electric field, specific absorption rate, and temperature rise in the human body and heart are less than the safety limits specified in the ICNIRP. The electric field intensity at the pacemaker electrode and the temperature rise of the pacemaker meet the requirements of the medical device standards of ICNIRP and ISO 14708-2. Consequently, the electromagnetic radiation from the motor operation in the electric vehicle does not pose a safety risk to the health of passengers wearing cardiac pacemakers in this paper. This study also contributes to advancing research on the electromagnetic environment of electric vehicles and provides guidance for ensuring the safe travel of individuals wearing cardiac pacemakers.


Asunto(s)
Campos Electromagnéticos , Marcapaso Artificial , Humanos , Electricidad , Vehículos a Motor
5.
Life (Basel) ; 14(5)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38792662

RESUMEN

BACKGROUND: Implanted titanium skull plates (TSPs) in cranioplasty are used to replace or reconstruct areas of the skull that have been damaged or removed due to trauma, surgery, or other medical conditions. However, the presence of a TSP in the head may influence the distribution of the electric field induced during transcranial magnetic stimulation (TMS) procedures. The purpose of this study was to determine how the presence of TSP would interfere with TMS-induced cortical electric fields. METHODS: The TMS with a figure-of-eight coil was applied to a realistic head model with TSPs. The distribution of the induced electric field in head tissues was calculated by employing the impedance method, and the results were compared with that of a normal head without TSP. RESULTS: Simulation results show that the distribution of the induced electric field has changed greatly for the head model with TSP. The maximum value of the induced electric field in head tissues was present under one of the circular coil wings rather than in the tissues beneath the junction of the two wings of the Fo8 coil. CONCLUSIONS: The induced electric field in deep brain regions was increased for the head model with TSP, which could potentially lead to deep brain stimulation. Since the presence of metallic TSP can greatly influence the distribution of the induced electric field in TMS applications, it is important to adjust the treatment scheme when considering TMS for individuals with cranial titanium plates.

6.
PLoS One ; 19(3): e0300049, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38466737

RESUMEN

In order to assess the electromagnetic exposure safety of passengers under the civil communication system of the subway, the radio-frequency (RF) electromagnetic environment of subway carriage is established by using COMSOL Multiphysics software, it includes a 1-1/4 " leaky coaxial cable (LCX1) and a 1-5/8" leaky coaxial cable (LCX2), which are designed to be the exposure sources, and twelve passengers at different position. The electromagnetic environment model has been verified through field measurement. The exposure dose distribution of twelve passengers is compared and analyzed, when LCX1 and LCX2 works respectively. The simulated results show that, to compare with LCX2, the electromagnetic dose absorbed by the passengers is reduced by 9.19% and 22.50% at 2100 MHz and 2600 MHz respectively. The specific absorption rate (SAR) of passengers obtains the maximum value of 1.91×10-4 W/Kg and the temperature rise to 0.214 K when the LCX1 works at 3400 MHz. By comparing with the public exposure limitation of the International Commission of Non-Ionizing Radiation Protection (ICNIRP), it demonstrates the electromagnetic exposure safety of the passengers under the civil communication system. More importantly, the proposed LCX1 not only could add the 5G signal cover but also lower the SAR absorbed by the passengers, which indicates that the public electromagnetic exposure dose could be reduced by adjusting the radiation performances of exposure source, which provide a new way for electromagnetic protecting.


Asunto(s)
Campos Electromagnéticos , Vías Férreas , Campos Electromagnéticos/efectos adversos , Ondas de Radio/efectos adversos , Temperatura , Comunicación
7.
Radiat Prot Dosimetry ; 200(6): 588-597, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38486443

RESUMEN

When the popular means of transportation-high-speed trains meet the increasing rate of pacemaker implantation year by year, the research on the magnetic field environment on the health of pacemaker wearers in the carriage becomes an urgent problem. In this work, models of an electric multiple unit carriage with a pantograph as well as passengers with pacemakers were built by using COMSOL Multiphysics software. The B, Ein and Jin of human heart and other tissues, and the induced voltage (Vin) at the pacemaker electrode were calculated under the pantograph operating condition, so as to assess the effect of its magnetic field on the health of pacemaker wearers. The results showed that Bmax in the carriage without passengers is 121.246 µT, occurs near the window. In the carriage, the Bmax, Ein max and Jin max of heart and body, Vin at the pacemaker electrode of the passenger next to the window are greater than that in the middle of the carriage. The Bmax, Ein max and Jin max of passengers' heart are 11.301µT, 1.613 mV/m and 139.030 µA/m2, respectively. The Bmax, Ein max and Jin max of passengers' body are 12.597µT, 0.788 mV/m and 75.299 µA/m2, respectively. The maximum value of Vin at the tip of the pacemaker electrode of the passengers' is 0.048 mV. The Bmax, Ein max in all tissues of passengers are much smaller than the basic limits of electromagnetic exposure to the public set by the International Commission on Non-Ionizing Radiation. Vin at the electrode tip of passengers' pacemakers are less than the perception sensitivity set by the International Organization for Standardization. This work illustrated that the magnetic field generated by the pantograph is within the recognized accepted limits for passengers with pacemakers, but we still recommended that passengers wearing pacemakers should stay as far away from windows as possible.


Asunto(s)
Campos Electromagnéticos , Marcapaso Artificial , Humanos , Campos Electromagnéticos/efectos adversos , Campos Magnéticos
8.
Radiat Prot Dosimetry ; 200(2): 187-200, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38038046

RESUMEN

This study employs the transient finite element method and electromagnetic heat transfer theory to assess the heating generated by high-power wireless chargers during electric vehicle charging. The analysis includes simulating and analyzing the temperature distribution of two different types of shielding plates of the wireless charger and the specific absorption rate (SAR) and head temperature rise of both adults and children in close proximity to the charger. Simulation results show that the maximum temperature rise of the copper shielding plate is 16°C lower than that of the aluminum shielding plate after charging for 1 h. This temperature increase does not affect the chassis' s equipment. Regarding human safety, the induced electric field strength and SAR values in the child's head tissue are higher than those in the adult, meeting the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits. When the initial temperature is set to 37°C, the temperature rise in the heads of both adults and children is approximately equal after 1 h of charging, reaching a maximum temperature rise of 0.21 and 0.23°C, respectively. These values remain below the thermal limit of ICNIRP (2°C for Type 2 tissues). The findings indicate that the copper shielding plate can provide both electromagnetic shielding and heat dissipation functions, and the electromagnetic exposure absorbed by the human body and head temperature rise within safe ranges.


Asunto(s)
Cobre , Suministros de Energía Eléctrica , Niño , Adulto , Humanos , Temperatura , Simulación por Computador , Campos Electromagnéticos
9.
Pediatrics ; 151(Suppl 2)2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37125889

RESUMEN

OBJECTIVES: Delayed child skill development is a common phenomenon in low- and middle-income countries. Effective and low-cost strategies suitable for application to less-developed countries are needed. We summarize empirical findings from recent papers that study a replication of the Jamaica Reach Up and Learn home visiting program in China, China REACH, and compare child skill growth profiles in the China Reach Up and Jamaica interventions. METHODS: Different interventions often use different measures for assessing early childhood skill development. To estimate the growth of underlying skills across programs, we address the challenge that different programs use different assessments. We use a modified version of the Rasch model to anchor scores on common items to estimate skill development. RESULTS: Language skill growth curves are comparable for both interventions. This pattern is consistent for the treatment and control groups across the interventions. Skill growth curves are not statistically significantly different between China REACH and Jamaican interventions. We find evidence of the importance of early investment. CONCLUSIONS: The China REACH intervention significantly improves the development of multiple skills. At the same ages, treatment effect sizes and skill growth curves are comparable across the Jamaica and China REACH interventions, despite differences in scale and cultural settings. The scale of the program is much greater in China than in Jamaica, showing that the Jamaican curriculum can be effectively expanded to larger populations. Annual costs per child are roughly $500 (2015 US dollars).


Asunto(s)
Desarrollo Infantil , Curriculum , Niño , Humanos , Preescolar , Jamaica , Países en Desarrollo , China
10.
Radiat Prot Dosimetry ; 199(3): ncac269 216 229-234, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36562627

RESUMEN

On the basis of the basic principle of electromagnetic dosimetry, the paper studies the electromagnetic exposure of a passenger's body to a compound electromagnetic field caused by the combined action of DC and AC bus currents of a pure electric vehicle inverter. By building an electromagnetic model of a pure electric vehicle body, adult human body and inverter, the finite element method is used to calculate the magnetic induction intensity(|B|), induced electric field intensity(|E|) and induced current density(|J|) of the compound electromagnetic field to the human trunk and central nervous system in the driver and front seat passenger. The numerical results are compared with the exposure limits defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The fields are well below the safe exposure limits defined by ICNIRP.


Asunto(s)
Campos Electromagnéticos , Protección Radiológica , Adulto , Humanos , Cuerpo Humano , Electricidad , Radiometría
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(4): 685-693, 2022 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-36008332

RESUMEN

Currently, transcranial magnetic stimulation (TMS) has been widely used in the treatment of depression, Parkinson's disease and other neurological diseases. To be able to monitor the brain's internal activity during TMS in real time and achieve better treatment outcomes, the researchers proposed combining TMS with neuroimaging methods such as magnetic resonance imaging (MRI), both of which use Tesla-level magnetic fields. However, the combination of strong current, large magnetic field and small size is likely to bring physical concerns which can lead to mechanical and thermal instability. In this paper, the MRI static magnetic field, the TMS coil and human head model were built according to the actual situations. Through the coupling of the magnetic field and the heat transfer module in the finite element simulation software COMSOL, the force and temperature of the TMS coil and head were obtained when the TMS was used in combination with MRI (TMS-MRI technology). The results showed that in a 3 T MRI environment, the maximum force density on the coil could reach 2.51 × 109 N/m3. Both the direction of the external magnetic field and the current direction in the coil affected the force distributions. The closer to the boundary of the external magnetic field, the greater the force. The magnetic field generated by the coil during TMS treatment increased the temperature of the brain tissue by about 0.16 °C, and the presence of the MRI static magnetic field did not cause additional thermal effects. The results of this paper can provide a reference for the development of the use guidelines and safety guidelines of TMS-MRI technology.


Asunto(s)
Imagen por Resonancia Magnética , Estimulación Magnética Transcraneal , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Humanos , Campos Magnéticos , Imagen por Resonancia Magnética/métodos , Temperatura , Estimulación Magnética Transcraneal/métodos
12.
J Fish Biol ; 101(1): 144-153, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35514248

RESUMEN

Tripartite motif (TRIM) proteins play a regulatory function in cancer, cell apoptosis and innate immunity. To understand the role of TRIM39 in Nile tilapia (Oreochromis niloticus), TRIM39 cDNA was isolated. The total length of TRIM39 cDNA was 5025 bp. The deduced OnTRIM39 protein contains 549 amino acids and has conserved domains of the TRIM family, which are the RING, B-box, coiled-coil and PRY-SPRY domains. OnTRIM39 mRNA was widely expressed in various tissues. After challenge with Streptococcus agalactiae and stimulation with polyinosinic polycytidylic acid [poly (I:C)] and lipopolysaccharides (LPS), the amount of OnTRIM39 transcript was changed in various tested tissues. OnTRIM39 overexpression increased NF-κB activity. OnTRIM39 was present in the cytoplasm. Mass spectrometry of proteins pulled down with recombinant OnTRIM39 showed that 250 proteins potentially interact with OnTRIM39. The authors selected I3K4I3 from the 250 candidate proteins to verify its interaction with TRIM39. They also selected I3KL45, a member of the same 14-3-3 protein family, to verify its interaction with TRIM39. The results of pull-down assays showed that OnTRIM39 interacted with both I3K413 and I3KL45. These results contribute to further study of the innate immune mechanism of tilapia.


Asunto(s)
Cíclidos , Enfermedades de los Peces , Infecciones Estreptocócicas , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Cíclidos/metabolismo , ADN Complementario , Proteínas de Peces/metabolismo , Regulación de la Expresión Génica , Inmunidad Innata , FN-kappa B/genética , FN-kappa B/metabolismo , Poli I-C/farmacología , Streptococcus agalactiae
13.
Dis Aquat Organ ; 149: 33-45, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35510819

RESUMEN

The largemouth bass Micropterus salmoides is an important freshwater aquaculture fish in China. Recently, largemouth bass at a fish farm in Guangdong province experienced an outbreak of a serious ulcer disease. As part of the investigations conducted to identify the aetiology and identify potentially effective control measures, we isolated a pathogenic bacterium (NK-1 strain) from the diseased fish. It was identified as Nocardia seriolae through morphological observation, physiological and biochemical analysis, and molecular identification, and its pathogenicity was verified by experimental infection. Pathological changes in the diseased fish included granulomatous lesions in the liver and spleen, destruction of renal tubules, necrosis of intestinal epithelial cells, infiltration of inflammatory cells in the brain, vacuolation of cells, and swelling and cracking of the mitochondria and endoplasmic reticulum. Bacterial detection using qPCR showed that the spleen and intestine were the main organs targeted by N. seriolae. The mortality of largemouth bass experimentally infected with N. seriolae at 21°C was significantly lower than that in fish infected at higher temperatures between 24 and 33°C; there were no significant differences in the levels of mortality at these higher temperatures. The level of mortality of largemouth bass infected with N. seriolae was lowest at a neutral water pH of 7 but increased significantly at higher and lower pH. Of the tested Chinese herbal medicines, Chinese sumac Galla chinensis and Chinese skullcap Scutellaria baicalensis exhibited the best antibacterial effects. This study lays a foundation for the clinical diagnosis and scientific control of ulcer disease in largemouth bass.


Asunto(s)
Lubina , Enfermedades de los Peces , Nocardia , Animales , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/microbiología , Úlcera/veterinaria
14.
Dev Comp Immunol ; 127: 104300, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34673140

RESUMEN

Toll-like receptors (TLRs) play a critical role in the innate immune response of fish. In this study, we isolated the cDNA sequence of Nile tilapia TLR1 (OnTLR1). The deduced OnTLR1 protein contains a signal peptide, 7 leucine-rich repeats (LRRs), a C-terminal LRR (LRR-CT), a transmembrane region and a highly conserved TIR domain. In healthy Nile tilapia, the OnTLR1 transcript was broadly expressed in all examined tissues, with the highest expression levels in the spleen. After infection with Streptococcus agalactiae, the OnTLR1 transcripts were upregulated in the gill and kidney. After stimulation with polyinosinic-polycytidylic acid (poly(I:C)), the expression levels of OnTLR1 were significantly downregulated in the intestine, whereas OnTLR1 transcripts were significantly upregulated in the kidney. After challenge with lipopolysaccharide (LPS), the expression levels of OnTLR1 were significantly upregulated in the spleen and kidney. The subcellular localization showed that OnTLR1 was expressed in the cytoplasm. TLR1 significantly increased MyD88-dependent NF-κB activity. However, the results of a pull-down assay showed that OnTLR1 did not interact with MyD88 or TIRAP. Binding assays revealed the specificity of OnTLR1 for pathogen-associated molecular patterns (PAMPs) and bacteria that included S. agalactiae, Aeromonas hydrophila and poly(I:C) and LPS. Taken together, these findings suggest that OnTLR1, as a pattern recognition receptor (PRR), might play an important role in the immune response to pathogen invasion.


Asunto(s)
Cíclidos , Enfermedades de los Peces , Animales , Proteínas de Peces/metabolismo , Regulación de la Expresión Génica , Inmunidad Innata/genética , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Filogenia , Streptococcus agalactiae , Receptor Toll-Like 1/genética
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 528-538, 2021 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-34180199

RESUMEN

Cholangiocarcinoma is a highly malignant tumor. It is not sensitive to radiotherapy and chemotherapy and has a poor prognosis. At present, there is no effective treatment. As a new method for treating cancer, magnetic fluid hyperthermia has been clinically applied to a variety of cancers in recent years. This article introduces it to the cholangiocarcinoma model and systematically studies the effect of magnetic fluid hyperthermia on cholangiocarcinoma. Starting from the theory of magnetic fluid heating, the electromagnetic and heat transfer models were constructed in the finite element simulation software COMSOL using the Pennes biological heat transfer equation. The Helmholtz coil was used as an alternating magnetic field generating device. The relationship between the magnetic fluid-related properties and the heating power was analyzed according to Rosensweig's theory. After the multiphysics coupling simulation was performed, the electromagnetic field and thermal field distribution in the hyperthermia region were obtained. The results showed that the magnetic field distribution in the treatment area was uniform, and the thermal field distribution met the requirements of hyperthermia. After the magnetic fluid injection, the cholangiocarcinoma tissue warmed up rapidly, and the temperature of tumor tissues could reach above 42 °C, but the surrounding healthy tissues did not heat up significantly. At the same time, it was verified that the large blood vessels around the bile duct, the overflow of the magnetic fluid, and the eddy current heat had little effect on thermotherapy. The results of this article can provide a reference for the clinical application of magnetic fluid hyperthermia for cholangiocarcinoma.


Asunto(s)
Colangiocarcinoma , Hipertermia Inducida , Humanos , Hipertermia , Campos Magnéticos , Magnetismo
16.
Mol Immunol ; 132: 60-78, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33545626

RESUMEN

Toll-like receptors (TLRs) play a crucial role in the innate immune system, which is the first line of defence against pathogens and pathogenic products in fish. In the present study, we cloned the full-length cDNA and genome sequences of two TLR13 s (OnTLR13a, OnTLR13b) from Nile tilapia (Oreochromis niloticus). TLR family motifs, i.e., the leucine-rich repeat (LRR) domains and Toll/interleukin (IL)-1 receptor (TIR) domains, were conserved in the putative proteins OnTLR13a and OnTLR13b, with fifteen LRR domains and one TIR domain. Four exons and three introns were identified in the OnTLR13a genome sequence, and three exons and two introns were identified in the OnTLR13b genome sequence. In healthy Nile tilapia tissues, OnTLR13a and OnTLR13b were ubiquitously expressed in all 11 tested tissues/organs. The highest expression levels were observed in the spleen (OnTLR13a) and blood (OnTLR13b), and the lowest expression levels were observed in the liver (OnTLR13a) and stomach (OnTLR13b). The expression level of OnTLR13b at 5.5 days postfertilization (dpf) was significantly higher than that at the other 8 time points (2.5, 3.5, 4.5, 5, 6, 6.5, 7.5 and 8.5 dpf). Upon stimulation with an intraperitoneal injection of 200 µL (107 CFU/mL) Streptococcus agalactiae, the expression levels of OnTLR13a and OnTLR13b were significantly upregulated in the intestine and gill. After cotransfection with MyD88, OnTLR13a significantly increased MyD88-dependent NF-κB activation in 293 T cells. However, OnTLR13b significantly impaired MyD88-dependent NF-κB activation. In addition, TLR13a slightly increased MyD88-dependent AP-1 activation, and TLR13b significantly increased MyD88-dependent AP-1 activation. TLR13a significantly increased MyD88-dependent interferon-ß (IFN-ß) activation, and TLR13b had no effect on MyD88-dependent IFN-ß activation. These findings suggest that although the deduced protein structure of OnTLR13 is evolutionarily conserved between OnTLR13 and other TLR members, its signal transduction function is markedly different. Co-immunoprecipitation (Co-IP) assays showed that both OnTLR13a and OnTLR13b could interact with OnMyD88. RNA pulldown assays showed that TLR13a and TLR13b could combine with the 23S rRNA of S. agalactiae. These results indicate that TLR13a and TLR13b play important roles in the innate immune response against bacterial infection in Nile tilapia.


Asunto(s)
Cíclidos/genética , Cíclidos/inmunología , Inmunidad Innata/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Streptococcus agalactiae/inmunología , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Secuencia de Aminoácidos , Animales , Sangre/metabolismo , Cíclidos/metabolismo , Cíclidos/microbiología , Exones , Enfermedades de los Peces/inmunología , Proteínas de Peces/genética , Regulación de la Expresión Génica/inmunología , Células HEK293 , Humanos , Interferón beta/metabolismo , Intrones , Hígado/metabolismo , FN-kappa B/metabolismo , Filogenia , Dominios Proteicos , ARN Ribosómico 23S/genética , Alineación de Secuencia , Transducción de Señal/inmunología , Bazo/metabolismo , Factor de Transcripción AP-1/metabolismo
17.
Ann Work Expo Health ; 64(8): 838-851, 2020 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-32483584

RESUMEN

The objective of this work is to evaluate the safety of the electromagnetic environment in the carriage of high-speed trains exposed to power cables when the train is full of passengers. The electromagnetic model of a real carriage, two sets of power cables and the 84 passengers were set up by using COMSOL Multiphysics software based on CRH5. The distributions of induced electric and magnetic fields in the carriage, inside and on the surface of passengers were investigated. The results show that the induced electric and magnetic fields on the windows are greater than on the passengers and the max value of induced magnetic field is 2627.10 µT, and the max value of induced electric field is 2.0 × 105 mV m-1. The maximum values of the induced electric and magnetic fields in 84 passengers' brain tissues were obtained, and it was found that the maximum values occurred in the third row passengers. The distribution of induced electric and magnetic fields at the cross-section of passengers' heads in the third row was also obtained, and we found that the passengers at the window side were greater than those of aisle passengers. In the third row, the maximum values of the induced electric and magnetic fields in the head of two passengers near the window were 94.6 mV m-1, 90.9 µT, 96.3 mV m-1, and 90.4 µT, respectively. We also found the all data were below the ICNIRP Reference Levels, which indicates the electromagnetic exposure caused by power cables when the train is full of passengers will not threat passengers' health.


Asunto(s)
Campos Electromagnéticos , Campos Electromagnéticos/efectos adversos , Humanos , Campos Magnéticos , Exposición Profesional , Vías Férreas
18.
Phys Med Biol ; 65(2): 025007, 2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31796653

RESUMEN

Deep transcranial magnetic stimulation (dTMS) is a non-invasive technique used for the treatment of depression and obsessive compulsive disorder. In this study, we computationally evaluated group-level dosage for dTMS to characterize the targeted deep brain regions to overcome the limitations of using individualized head models to characterize coil performance in a population. We used an inter-subject registration method adapted to the deep brain regions that enable projection of computed electric fields (EFs) from individual realistic head models (n = 18) to the average space of deep brain regions. The computational results showed consistent group-level hotspots of the EF in the deep brain regions. The halo circular assembly coils induced the highest EFs in deep brain regions (up to 50% of the maximum EF in the cortex) for optimized positioning. In terms of the trade-off between field spread and penetration, the performance of the H7 coil was the best. The computational model allowed the optimization of generalized dTMS-induced EF on deep region targets despite inter-individual differences while informing and possibly minimizing unintended stimulation of superficial regions and possible mixed stimulation effects from deep and cortical areas. These results will facilitate the decision process during dTMS interventions in clinical practice.


Asunto(s)
Encéfalo/fisiología , Electricidad , Estimulación Magnética Transcraneal/instrumentación , Simulación por Computador , Diseño de Equipo , Humanos
19.
BMC Neurosci ; 20(1): 40, 2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31387538

RESUMEN

BACKGROUND: Transcranial direct current stimulation (tDCS) is a noninvasive neural control technology that has become a research hotspot. To facilitate further research of tDCS, the biosafety of 500 µA cathodal tDCS, a controversial parameter in rats was evaluated. RESULTS: 24 animals were randomly divided into two groups: a cathodal tDCS group (tDCS, n = 12) and control group (control, n = 12). Animals in the tDCS group received 5 consecutive days of cathodal tDCS (500 µA, 15 min, once per day) followed by a tDCS-free interval of 2 days and 5 additional days of stimulation, totally two treatments of tDCS for a total of 10 days. Computational 3D rat model was adopted to calculate the current density distributions in brain during tDCS treatment. Essential brain functions including motor function and learning and memory ability were evaluated. Additionally, to estimate the neurotoxicity of tDCS, the brain morphology, neurotransmitter levels and cerebral temperature were investigated. Our results showed that the current density inside the brain was less than 20 A/m2 during tDCS treatment in computational model. tDCS did not affect motor functions and learning and memory ability after tDCS treatment. In addition, no significant differences were found for the tDCS group in hematology, serum biochemical markers or the morphology of major organs. Moreover, tDCS treatment had no effect on the brain morphology, neural structures, neurotransmitter levels or cerebral temperature. CONCLUSION: 500 µA cathodal tDCS as performed in the present study was safe for rodents.


Asunto(s)
Biomarcadores/sangre , Aprendizaje/fisiología , Memoria/fisiología , Actividad Motora/fisiología , Corteza Motora/fisiología , Seguridad , Estimulación Transcraneal de Corriente Directa/efectos adversos , Animales , Simulación por Computador , Hipocampo/metabolismo , Pruebas de Función Renal , Pruebas de Función Hepática , Masculino , Corteza Motora/metabolismo , Corteza Motora/patología , Neurotransmisores/metabolismo , Ratas , Prueba de Desempeño de Rotación con Aceleración Constante , Temperatura
20.
Fish Shellfish Immunol ; 94: 249-257, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31470139

RESUMEN

In recent years, streptococcal diseases have severely threatened the development of tilapia aquaculture, but effective prevention and control methods have not yet been established. To understand the immune responses of vaccinated Nile tilapia (Oreochromis niloticus), digital gene expression (DGE) technology was applied in this study to detect the gene expression profile of the Nile tilapia (O. niloticus) liver in response to ScpB (Streptococcal C5a peptidase from group B Streptococcus, ScpB) vaccination and a Streptococcus agalactiae-challenge. The control and the ScpB-vaccinated Nile tilapia yielded a total of 25,788,734 and 27,088,598 clean reads, respectively. A total of 1234 significant differentially expressed unigenes were detected (P < 0.05), of which 236 were significantly up-regulated, and 269 were significantly down-regulated (P < 0.05, |fold|>2, FDR<0.05). Of the differentially expressed gene, the identified genes which were enriched using databases of GO and KEGG could be categorized into a total of 67 functional groups and were mapped to 153 signaling pathways including 15 immune-related pathways. The differentially expressed genes (TLR1, TLR2, TLR3, TLR5, TLR9, MyD88, C3, IL-1ß, IL-10) were detected in the expression profiles, and this was subsequently verified via quantitative real-time PCR (qPCR). The results of this study can serve as a basis for future research not only on the molecular mechanism of S. agalactiae invasion, but also on the anti-S. agalactiae mechanism in targeted tissues of Nile tilapia.


Asunto(s)
Cíclidos/inmunología , Enfermedades de los Peces/genética , Perfilación de la Expresión Génica/veterinaria , Regulación de la Expresión Génica , Infecciones Estreptocócicas/veterinaria , Streptococcus agalactiae/fisiología , Animales , Cíclidos/genética , Regulación hacia Abajo , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/microbiología , Biblioteca de Genes , Ontología de Genes , Hígado/metabolismo , Hígado/microbiología , Infecciones Estreptocócicas/genética , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Vacunas Estreptocócicas/administración & dosificación , Regulación hacia Arriba
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