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1.
Rev. Pesqui. Fisioter ; 14(1)mar., 2024. tab, ilus
Article de Anglais, Portugais | LILACS | ID: biblio-1555417

RÉSUMÉ

INTRODUCTION: Shoulder pain after stroke, a complication with a prevalence of up to 16­84% usually occurs after 2­3 months and leads to patients withdrawing from rehabilitation programs, staying in the hospital longer, having less limb function and having a great negative impact on their quality of life. The aim of the present study was to determine the effect of PEMF and NMES in reducing shoulder pain in patients with stroke. MATERIAL AND METHODS: A prospective, randomized controlled trial included 51 patients with shoulder pain following stroke. The patients were randomly assigned to three groups (17 people in each group): Pulsed Electromagnetic Field (PEMF), Neuromuscular Electrical Stimulation (NMES) and Control group. The outcome measures were Visual Analogue Scale (VAS), Modified Ashworth Scale (MAS) and Fugl Meyer Assessment­Upper Extremity (FMA-UE), Active and Passive Range of Motion (AROM/PROM) assessed at the baseline, six weeks into the intervention, and one week into the follow-up. RESULTS: VAS score for pain showed a mean change of 1.60, 1.60 and 4.94 in PEMF, NMES, and control respectively after 20 sessions. It showed pain was significantly improved in all the groups (p<0.001), but the effectiveness of the PEMF and NMES groups was superior to the control group. CONCLUSION: The current literature showed that PEMF & NMES are effective in improving post-stroke shoulder pain, spasticity, range of motion and motor function and a novel method for stroke patients undergoing rehabilitation.


INTRODUÇÃO: Dor no ombro após acidente vascular cerebral com prevalência de 16­84% geralmente ocorre após 2­3 meses e pode resultar na suspensão de programas de reabilitação, internações hospitalares mais longas e redução da função dos membros, prejudicando qualidade de vida dos pacientes com AVC. O objetivo do presente estudo foi determinar o efeito da PEMF e da EENM na redução da dor no ombro em pacientes com acidente vascular cerebral. MATERIAL E MÉTODOS: Um estudo prospectivo, randomizado e controlado incluiu 51 pacientes com dor no ombro pós-AVC. Os pacientes foram divididos aleatoriamente em três grupos (17 pessoas em cada grupo): grupo Campo Eletromagnético Pulsado (PEMF), grupo Estimulação Elétrica Neuromuscular (EENM) e grupo Controle. As medidas de resultados foram na Escala Visual Analógica (VAS), Escala de Ashworth Modificada (MAS) e Avaliação de Fugl Meyer ­ Extremidade Superior (FMA-UE), Amplitude de Movimento (AROM/PROM) foram avaliadas no início do estudo, após seis semanas de tratamento, e após um acompanhamento semanal. RESULTADOS: A pontuação VAS para dor mostrada uma alteração média de 1,60, 1,60 e 4,94 na PEMF, EENM e Controle, respectivamente, após 20 sessões. Mostrou melhora significativa entre os três grupos (p<0,001), mas a eficácia do grupo PEMF e EENM foi superior ao grupo Controle. CONCLUSÃO: O presente estudo mostrou que PEMF e EENM são eficazes na melhora da dor no ombro pós-AVC, espasticidade, amplitude de movimento e função motora e um novo método para pacientes com AVC em reabilitação. Nossas descobertas indicam que a eficácia da EENM é claramente superior à do PEMF na manutenção da analgesia a longo prazo.


Sujet(s)
Accident vasculaire cérébral , Scapulalgie , Stimulation électrique
2.
Heliyon ; 10(3): e24927, 2024 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-38317962

RÉSUMÉ

Understanding the effects of electromagnetic fields is crucial in the fermentation of cocoa beans, since through precise control of fermentation conditions the sensory and nutritional properties of cocoa beans could be improved. This study aimed to evaluate the effect of oscillating magnetic fields (OMF) on the kinetic growth of the core microbial communities of the Collections Castro Naranjal (CCN 51) cocoa bean. The data was obtained by three different models: Gompertz, Baranyi, and Logistic. The cocoa beans were subjected to different OMF strengths ranging from 0 mT to 80 mT for 1 h using the Helmholtz coil electromagnetic device. The viable microbial populations of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeast (Y) were quantified using the colony-forming unit (CFU) counting method. The logistic model appropriately described the growth of LAB and Y under magnetic field exposure. Whereas the Baranyi model was suitable for describing AAB growth. The microbial populations in cocoa beans exposed to magnetic fields showed lower (maximum specific growth rate (µmax), values than untreated controls, with AAB exhibiting the highest average growth rate value at 5 mT and Y having the lowest average maximum growth rate value at 80 mT. The lower maximum specific growth rates and longer lag phases when exposed to magnetic fields compared to controls demonstrate the influence of magnetic fields on microbial growth kinetics.

3.
Heliyon ; 9(9): e20323, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37809888

RÉSUMÉ

Exposure to radiofrequency electromagnetic fields (RF-EMFs) is considered an area of significant importance in the medical and scientific community. However, the availability of exposure data for indoor and outdoor locations in universities is limited and currently inconsiderate in Latin America. The aim of this work was to evaluate the electric field levels due to mobile telecommunication technologies and Wi-Fi to which students and faculty staff from two campuses of a higher education institution are exposed. Using a portable spectrum analyzer, we carried out 516 short-term measurements in the 800-3000 MHz frequency range at both indoor and outdoor locations. These locations were chosen to cover all areas of the assessed buildings. The electric field differences between floors and buildings are discussed. Finally, we compared the electric field levels with exposure limits. The highest electric field level measured was 13.97 V/m at the 850 MHz band. However, the average electric field values were below 2 V/m. The greatest contribution to the total electric field was due to sources using the 850 MHz and 1900 MHz bands (98%), while the contribution of the Wi-Fi network was low (1.0%). The results show that all the electric field levels measured were lower than the ICNIRP reference levels for radio-frequency exposure.

4.
Heliyon ; 9(4): e15065, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-37077687

RÉSUMÉ

Acid and bitter notes of the cocoa clone Cacao Castro Naranjal 51 (CCN 51) negatively affect the final quality of the chocolate. Thence, the fermentative process of cocoa beans using native species and electromagnetic fields (EMF) was carried out to evaluate the effect on the yield and quality of CCN 51 cocoa beans. The variables magnetic field density (D), exposure time (T), and inoculum concentration (IC) were optimized through response surface methodology to obtain two statistically validated second-order models, explaining 88.39% and 92.51% of the variability in the yield and quality of the beans, respectively. In the coordinate: 5 mT(D), 22.5 min (T), and 1.6% (CI), yield and bean quality improved to 110% and 120% above the control (without magnetic field). The metagenomic analysis showed that the changes in the microbial communities favored the aroma profile at low and intermediate field densities (5-42 mT) with high yields and floral, fruity, and nutty notes. Conversely, field densities (80 mT) were evaluated with low yields and undesirable notes of acidity and bitterness. The findings revealed that EMF effectively improves the yield and quality of CCN 51 cocoa beans with future applications in the development and quality of chocolate products.

5.
J Cosmet Dermatol ; 22(4): 1266-1272, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-36718803

RÉSUMÉ

BACKGROUND: Currently, even individuals who do physical activity regularly have some degree of dissatisfaction with their own bodies. The electromagnetic field for supramaximal muscle contraction has been the subject of research. High-intensity supramaximal muscle stimulation (HI-SMS) is a non-invasive technology used to strengthen, firm, and tone the abdominal muscles, arms, buttocks, and thighs and has been indicated for aesthetic purposes. AIMS: The present study aimed to examine the safety and efficacy of HI-SMS used in the abdominal muscles of patients through the analysis of clinical evaluation, biochemical serum profile, and patient satisfaction with the procedure. PATIENTS/METHODS: This is retrospective non-randomized and non-controlled study collected in a private clinic; all data from healthy participants (n = 25), aged between 18 and 55 years, were compiled and analyzed. All received eight 30 min sessions of electromagnetic field ONIX HI-SMS (intensity of the 90%-100%) located in abdominal, twice a week with intervals of 2-3 days. RESULTS: The results show that BMI, fat thickness, and waist circumference improved the body contour after the treatment. There was no statistical difference in the data referring to the values of AST, ALT, ALP, creatinine, cholesterol, LDL-C, VLDL-C, HDL-C, glycemia, LDH, CK, and IL-6. However, there was a reduction of "non-esterified" free fatty acids when compared to baseline. This treatment provided high levels of tolerance, comfort, and high level of satisfaction. CONCLUSIONS: Thus, it can be suggested that the treatment with HI-SMS in abdominal muscles proves to be a safe technology with potential for non-invasive therapy for aesthetic purposes.


Sujet(s)
Muscles abdominaux , Magnétothérapie , Contraction musculaire , Satisfaction des patients , Adolescent , Adulte , Humains , Adulte d'âge moyen , Jeune adulte , Brésil , Champs électromagnétiques , Études rétrospectives , Résultat thérapeutique , Contraction musculaire/physiologie , Magnétothérapie/méthodes , Muscles abdominaux/physiologie , Esthétique
6.
Rev. cuba. invest. bioméd ; 40(2): e570, 2021. graf
Article de Espagnol | LILACS, CUMED | ID: biblio-1347461

RÉSUMÉ

Introducción: El panorama demográfico en el mundo está cambiando. La población mayor de 60 años es el segmento que está creciendo más rápidamente y en el que las enfermedades del tejido óseo se presentan con más frecuencia, lo que aumenta la demanda de materiales y tecnologías apropiadas para restaurar estos tejidos. Objetivo: Analizar la información que se ha generado sobre el desarrollo de biomateriales compuestos para la reparación ósea, con énfasis en la identificación de las tecnologías emergentes basadas en el uso del campo electromagnético, sus aplicaciones y potencialidades. Métodos: Se consultaron trabajos científicos publicados en libros, revistas, patentes y tesis. El 80 por ciento de la documentación seleccionada pertenece al periodo 2010-2019. Análisis e integración de la información: Los métodos identificados fueron clasificados en cinco grupos: electrodeposición química, ya sea por electrólisis, electroforesis o síntesis electroforética in situ; electroporación; electrohilado; control magnético distal y bioestimulación electromagnética de células y tejidos, directamente o por la introducción de dispositivos que convierten la energía electromagnética en energía mecánica. Conclusiones: Estos métodos permiten la conformación de matrices celulares y acelulares compuestas y, además, dispositivos bioestimuladores con control de los parámetros de construcción y acción, de tal manera, que se logran procesos con mayor grado de reproducibilidad y a la medida de los requerimientos específicos para cada paciente(AU)


Introduction: The global demographic panorama is changing. The population aged over 60 years is the fastest growing segment, as well as the one where bone tissue diseases are most common, increasing the demand of appropriate materials and technologies to restore those tissues. Objective: To analyze the information so far generated about the development of composite biomaterials for bone repair, with an emphasis on the identification of emerging technologies based on the use of the electromagnetic field, its applications and potential. Methods: An analysis was performed of scientific papers published in books, journals, patents and theses. Of the documentation selected, 80 percent was from the period 2010-2019. Data analysis and integration: The methods identified were classified into five groups: chemical electrodeposition, be it by in situ electrophoretic synthesis, electrolysis or electrophoresis; electroporation; electrospinning; distal magnetic control and electromagnetic biostimulation of cells and tissues, either directly or incorporating devices which convert electromagnetic energy into mechanical energy. Conclusions: These methods permit the conformation of composite cellular and acellular matrices as well as biostimulator devices controlling construction and action parameters in such a way that the processes obtained display greater reproducibility and are more in keeping with the specific requirements of each patient(AU)


Sujet(s)
Humains , Matériaux biocompatibles/analyse , Stimulation électrique/méthodes , Champs électromagnétiques
7.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;79(2): 139-148, Feb. 2021. tab, graf
Article de Anglais | LILACS | ID: biblio-1153165

RÉSUMÉ

ABSTRACT Background: The use of technological devices is growing rapidly, and the use of cell phones increases in parallel. Dependence on technological devices is a particular factor in this increased exposure. Many studies have been performed on this electromagnetic field, but no definite conclusions have been drawn. Objective: The purpose of this research was to investigate exposure to electromagnetic field, cell phone use behaviors, the specific absorption rate (SAR) values, and changes in health occurring after exposure in university students. Methods: A questionnaire was administered to 1,019 volunteer students aged 18-24 years at the Niğde Ömer Halisdemir and Recep Tayip Erdoğan Universities in 2018-2019. The questions were based on a survey of the literature. Results: The students spent an average 4-8 hours per day on their cell phones, and findings such as headache (p=0.002), concentration deficit (p=0.001), tiredness on waking in the morning (p=0.001), hyperactivity (p=0.001), general feeling of fatigue (p=0.001), and lethargy (p=0.001) increased in a statistically significant manner with length of use. Conclusions: Participants exhibited high levels of cell phone use and experienced biological, behavioral, and sleep problems. They also had very little knowledge about specific SAR values, an important criterion concerning cell phones.


RESUMO Introdução: O uso de dispositivos tecnológicos está crescendo rapidamente e o uso de telefone celulares aumenta em paralelo. A dependência de dispositivos tecnológicos é um fator nesse aumento de exposição. Diversos estudos sobre o campo eletromagnético foram realizados, mas nenhuma conclusão definitiva foi alcançada. Objetivo: O objetivo desta pesquisa foi investigar a exposição ao campo eletromagnético, os comportamentos de uso do telefone celular, os valores de absorção específica (specific absorption rate — SAR) dos telefones celulares utilizados e as alterações na saúde ocorridas após a exposição em adolescentes universitários. Métodos: Um questionário foi aplicado a 1.019 alunos voluntários com idades entre 18-24 anos nas universidades Niğde Ömer Halisdemir e Recep Tayip Erdoğan em 2018-2019. As perguntas foram baseadas em um levantamento bibliográfico. Resultados: Os estudantes gastaram em média 4-8 horas por dia em seus celulares, e achados como cefaleia (p=0,002), dificuldade de concentração (p=0,001), cansaço ao acordar pela manhã (p=0,001), hiperatividade (p=0,001), sensação geral de fadiga (p=0,001) e letargia (p=0,001) aumentaram de forma estatisticamente significativa com o tempo de uso. Conclusões: Os participantes exibiram altos níveis de uso de telefone celular e problemas biológicos, comportamentais e de sono. Eles também tinham pouco conhecimento sobre valores específicos de SAR, um critério importante para telefones celulares.


Sujet(s)
Humains , Adolescent , Jeune adulte , Téléphones portables , Utilisation du téléphone portable , Étudiants , Universités , Champs électromagnétiques/effets indésirables
8.
Rev. cuba. ortop. traumatol ; 34(2): e231, jul.-dic. 2020. ilus
Article de Espagnol | CUMED, LILACS | ID: biblio-1156596

RÉSUMÉ

RESUMEN Introducción: Las fracturas abiertas del tercio distal de tibia o pilón son poco frecuentes, en nuestro medio se producen por traumas de alta energía como los accidentes de tránsito, y pueden ser de distintos grados según su envergadura. Entre las complicaciones frecuentes están la seudoartrosis, deformidades y artritis postraumática. Cuando el dolor es refractario a los analgésicos están indicadas las artrodesis. Objetivo: Presentar los resultados del tratamiento realizado en un paciente con seudoartrosis distal de tibia y artritis postraumática del tobillo, dolorosa, con gran lesión de partes blandas, por lo que fue imposible realizar los procedimientos quirúrgicos habituales. Presentación del caso: Se realizó artrodesis de las articulaciones tibio-peronea-astragalina-calcánea, mediante un injerto libre del peroné autólogo, compresión, y estabilización con un fijador externo RALCA®; se asoció un campo electromagnético pulsátil para acelerar la formación del callo óseo y disminuir el dolor posquirúrgico. Durante dos años se le hizo seguimiento. Conclusiones: Se logró el objetivo del tratamiento al fusionar la articulación tibiotarsiana, comenzar el apoyo precoz y su capacidad funcional. Los resultados demuestran además los beneficios de la compresión realizada con los fijadores externos en las artrodesis; el uso del campo electromagnético asociado aceleró la osteogénesis, se consiguió la consolidación ósea, la estabilización, disminuyó el edema y el dolor, además la reincorporación del paciente a la sociedad. No se encontró en la bibliografía revisada otra técnica quirúrgica similar(AU)


ABSTRACT Introduction: Open fractures of the distal third of the tibia or pilon are rare, in our environment they are caused by high-energy traumas such as traffic accidents, and can be of different degrees depending on their size. Common complications include nonunion, deformities, and post-traumatic arthritis. When pain is refractory to analgesics, arthrodesis is indicated. Objective: To report the results of the treatment carried out in a patient with distal tibial pseudoarthrosis and post-traumatic arthritis of the ankle, painful, with a large soft tissue injury, which made it impossible to perform the usual surgical procedures. Case report: Arthrodesis of the tibiofibular-talar-calcaneal joints was performed, using a free graft of the autologous fibula, compression, and stabilization with a RALCA® external fixator. A pulsatile electromagnetic field was associated to accelerate bone callus formation and reduce postoperative pain. This patient was followed up for two years. Conclusions: The treatment objective was achieved by fusing the tibiotarsal joint, by starting early support and functional capacity. The results also prove the benefits of compression performed with external fixators in arthrodesis. The use of the associated electromagnetic field accelerated osteogenesis, bone consolidation and stabilization were achieved, edema and pain decreased, as well as the patient's reincorporation into society. No other similar surgical technique was found in the reviewed literature(AU)


Sujet(s)
Arthrodèse/méthodes , Pseudarthrose/chirurgie , Fibula/transplantation , Fractures ouvertes/chirurgie
9.
Biofouling ; 36(7): 862-869, 2020 08.
Article de Anglais | MEDLINE | ID: mdl-32993357

RÉSUMÉ

The objective was to test the influence of a pulsed electromagnetic field (PEMF) on bacterial biofilm colonization around implants incorporated with healing abutments. Healing abutments with (test group) and without (control group) active PEMF devices were placed in a multispecies biofilm consisting of 31 different bacterial species. The biofilm composition and total bacterial counts (x105) were analyzed by checkerboard DNA-DNA hybridization. After 96 h, the mean level of 7 out of the 31 bacterial species differed significantly between groups, namely Eubacterium nodatum, Fusobacterium nucleatum ssp. nucleatum, Streptococcus intermedius, Streptococcus anginosus, Streptococcus mutans, Fusobacterium nucleatum ssp. Vicentii and Capnocytophaga ochracea were elevated in the control group (p < 0.05). The mean total bacterial counts were lower in the Test group vs the control group (p < 0.05). An electromagnetic healing cap had antimicrobial effects on the bacterial species and can be used to control bacterial colonization around dental implants. Further clinical studies should be conducted to confirm these findings.


Sujet(s)
Anti-infectieux , Bacteroides , Biofilms , Champs électromagnétiques , Capnocytophaga
10.
Braz. j. otorhinolaryngol. (Impr.) ; Braz. j. otorhinolaryngol. (Impr.);85(3): 282-289, May-June 2019. tab, graf
Article de Anglais | LILACS | ID: biblio-1011624

RÉSUMÉ

Abstract Introduction: In daily life biological systems are usually exposed to magnetic field forces at different intensities and frequencies, either directly or indirectly. Despite negative results, the therapeutic use of the low dose magnetic field has been found in recent studies. The effect of magnetic field forces on cochlear cells is not clear in the literature. Objective: In our study, we first applied in vivo pulsed magnetic fields to laboratory rats to investigate the effects on cochlea with distortion product otoacoustic emission test followed by histopathological examinations. Methods: Twelve rats were included in this study, separated into two groups as study group and control group. The rats in the study group were exposed to 40 Hz pulsed magnetic field for 1 h/day for 30 days; the hearing of the rats was controlled by otoacoustic emission test. Also, their cochleas were removed and histochemical examination was performed by Caspase-3, Caspase-9, and TUNEL methods. Results: A statistically significant difference was determined (p < 0.05) when the hearing thresholds of the groups obtained by using 5714 Hz and 8000 Hz stimuli were compared by Kruskal-Wallis test. A significant reaction was observed in the study group, especially in the outer ciliated cells during immunohistochemical examinations by using Caspase-3 and Caspase-9 methods. A significantly positive difference was determined in the study group, especially at the outer ciliated cells and the support cells of the corti organ, when compared to the control group (p < 0.05) by the TUNEL method. Conclusion: According to the results of our study, the very low dose magnetic field, which is considered to be used for therapeutic purposes recently, can cause both auditory function defects and histopathologic damage in cochlear cells.


Resumo Introdução: Os sistemas biológicos são geralmente expostos a forças de campo magnético em diferentes intensidades e frequências, direta ou indiretamente, na vida diária. Apesar dos resultados negativos, o uso terapêutico do campo magnético de baixa dose tem sido encontrado em estudos recentes. O efeito das forças do campo magnético sobre as células cocleares não está claro na literatura. Objetivo: Em nosso estudo, aplicamos pela primeira vez campos magnéticos pulsados in vivo em ratos de laboratório para investigar os efeitos na cóclea através do teste de emissão otoacústica por produto de distorção e análises histopatológicas. Método: Doze ratos foram incluídos neste estudo, os quais foram separados em dois grupos, grupo de estudo e grupo controle. Os ratos do grupo de estudo foram expostos a campo magnético pulsado de 40 Hz por 1 hora/dia por 30 dias, e a audição dos ratos foi controlada por testes de emissão otoacústica. Além disso, suas cócleas foram colhidas e o exame histoquímico foi feito pelos métodos caspase-3, caspase-9 e TUNEL. Resultados: Foi determinada uma diferença estatisticamente significante (p < 0,05) quando os limiares auditivos dos grupos obtidos por meio dos estímulos de 5714 Hz e 8000 Hz foram comparados pelo teste de Kruskal-Wallis. Uma reação significante foi observada no grupo de estudo, especialmente nas células ciliadas externas nas análises imuno-histoquímicas, com os métodos caspase-3 e caspase-9. Uma diferença significantemente positiva foi determinada no grupo de estudo, especialmente nas células ciliadas externas e nas células de suporte do órgão de Corti, quando comparadas com o grupo controle (p < 0,05) pelo método TUNEL. Conclusão: De acordo com os resultados do nosso estudo, o campo magnético de dose baixa, que tem sido considerado para uso terapêutico recentemente, pode causar defeitos na função auditiva e danos histopatológicos nas células cocleares.


Sujet(s)
Animaux , Mâle , Rats , Cochlée/anatomopathologie , Cellules ciliées auditives externes/anatomopathologie , Champs électromagnétiques/effets indésirables , Immunohistochimie , Rat Wistar , Émissions otoacoustiques spontanées , Statistique non paramétrique
11.
Int. j. morphol ; 37(2): 719-723, June 2019. tab, graf
Article de Anglais | LILACS | ID: biblio-1002283

RÉSUMÉ

Mobile phone use has increased rapidly. The central nervous system has been shown to be adversely affected by its electromagnetic field (EMF) resulting in headache and sleep disturbances. How the cells make up the CNS and are affected by EMF is unclear. However, because of their central role in inflammation through diverse stimuli including radiation, this study aimed to investigate the effects of electromagnetic fields induced by mobile phones on mast cells in rat dura mater. A total of 18 adult, female, SpragueDawley rats were divided into two groups. The choice of female rats for his study was based on recent surveys demonstrating that mobile phone use is more frequent and prolonged among females. The study group was exposed to 900 MHz electromagnetic field (1 h/day for 45 days). In the end of the study, duramater tissue was extracted and stained using Toluidine blue. Mast cells were counted and results were analysed using Student t test. Mean mast cell number was 202.33±9.82 and 456.78±35.01 in the control and study groups, respectively (p<0.05). Analysis of serum electrolyte and immunoglobulin E levels showed no statistically significant difference between the two groups (p>0.05). The study showed that mobile phone exposure increased mast cell number and degranulation in rat dura mater. Further studies are required to evaluate the clinical implications of these findings.


El uso del teléfono móvil ha aumentado rápidamente. Se ha demostrado que el sistema nervioso central (SNC) se ve afectado de manera adversa debido al campo electromagnético (CEM) que produce dolor de cabeza y trastornos del sueño. No está claro cómo se ve afectada la composición celular del SNC por el CEM. Sin embargo, debido a su función principal en la inflamación a través de diversos estímulos que incluyen la radiación, este estudio tuvo como objetivo investigar los efectos de los campos electromagnéticos inducidos por los teléfonos móviles en los mastocitos de la duramadre de ratas. Un total de 18 ratas Sprague-Dawley adultas, hembras, se dividieron en dos grupos. Se usaron ratas hembras para este estudio en base a investigaciones recientes que han demostrado que el uso de teléfonos móviles es más frecuente y prolongado en las mujeres. Los grupos de estudio fueron expuestos a un campo electromagnético de 900 MHz (1 h / día durante 45 días). Al término del estudio, fue extirpado el tejido de la duramadre y teñido con azul de toluidina. Se contaron los mastocitos y se analizaron los resultados utilizando la prueba t de Student. La cantidad media de células cebadas fue de 202,33 ± 9.82 y 456,78 ± 35,01 en los grupos control y estudio, respectivamente (p <0,05). El análisis del electrolito sérico y los niveles de inmunoglobulina E no mostraron diferencias estadísticamente significativas entre los dos grupos (p> 0,05). El estudio mostró que la exposición a teléfonos móviles aumentó el número de mastocitos y la desgranulación en la duramadre de las ratas. Se requieren estudios adicionales para evaluar las implicaciones clínicas de estos hallazgos.


Sujet(s)
Animaux , Rats , Téléphones portables , Dure-mère/effets des radiations , Champs électromagnétiques/effets indésirables , Mastocytes/effets des radiations , Rat Sprague-Dawley
12.
Sensors (Basel) ; 19(10)2019 May 22.
Article de Anglais | MEDLINE | ID: mdl-31121884

RÉSUMÉ

A sugar solution measurement system was developed based on the dielectric properties of the sucrose molecule. An ac conductivity and tan δ study as a function of the frequency was performed to find the suitable frequency range for the measuring system. The results indicate that it is possible to obtain a better response of the sensor using the frequencies as the maxima peak in tan δ appears. Developed setup for sucrose solution was appropriate to measure in a 0.15 to 1 g/mL range with an experimental error of about 3%. The proposed system improves the measurement time over some other methods.

13.
Bioelectromagnetics ; 40(2): 83-90, 2019 Feb.
Article de Anglais | MEDLINE | ID: mdl-30763468

RÉSUMÉ

This study was designed to evaluate the effect of pulsed signal therapy (PST) on patellofemoral pain syndrome associated with patellar chondropathy. A prospective randomized double-blind placebo controlled trial included 25 patients (41 knees) between 20 and 50 years with pain due to isolated patellofemoral syndrome with chondropathy. PST group received nine 60-min daily sessions of PST treatment. Control group received the same protocol of blinded placebo treatment. The main outcome was change from baseline Kujala score at 3 months. After 3 months, patients in the control group received effective treatment (placebo post-treatment). All patients were then followed, for up to 12 months. Seventeen knees (5 males and 12 females, mean age 36.7 ± 7.9) received placebo and 24 knees (8 males and 16 females, mean age 35.5 ± 8.9) received PST. By the third month, PST group exhibited a mean change from baseline of 9.63 ± 7.5 Kujala points, compared to 0.53 ± 1.8 in the placebo group (P < 0.001). A significant progressive improvement was seen in the PST group between the 3rd and 6th and between the 6th and 12th month (P < 0.016). Patients initially allocated in the control group also improved at 3 months (P < 0.001) and 6 months (P = 0.005) post-effective treatment. In conclusion, PST in patellofemoral pain syndrome with chondropathy was effective compared to placebo at 3 months, showing an important improvement of Kujala score. The improvement was progressive and maintained up to 12 months. PST is safe and should be considered as a non-invasive option for management of this condition. Bioelectromagnetics. 40:83-90, 2019. © 2019 Bioelectromagnetics Society.


Sujet(s)
Magnétothérapie/méthodes , Patella/traumatismes , Syndrome fémoro-patellaire/thérapie , Rachitisme/thérapie , Adulte , Méthode en double aveugle , Champs électromagnétiques , Femelle , Fémur/anatomopathologie , Humains , Maladies articulaires/traitement médicamenteux , Genou , Mâle , Adulte d'âge moyen , Mesure de la douleur , Syndrome fémoro-patellaire/complications , Résultat thérapeutique
14.
Braz J Phys Ther ; 23(3): 244-249, 2019.
Article de Anglais | MEDLINE | ID: mdl-30177406

RÉSUMÉ

BACKGROUND: Further research on pulsed electromagnetic field (PEMF) effects on the different conditions of low back pain was warranted due to lack of studies in this area. OBJECTIVES: To investigate the effects of pulsed electromagnetic field therapy with 50Hz frequency, with low intensity of 20Gauss compared to conventional non-invasive treatment modalities in patients with chronic non-specific low back pain. METHODS: Design - A prospective, randomized, patient-blinded, controlled trial. Setting - The study was conducted at Outpatient Physiotherapy Clinic in Cairo, Egypt. The study was conducted between May 2015 and September 2016. Participants - Fifty participants with non-specific low back pain enrolled into experimental and control groups. Interventions - The experimental group received the Conventional physical therapy Protocol as well as magnetic field, while the control group received the same Conventional physical therapy and sham electromagnetic field. Both groups received 12 sessions over 4 weeks' period. Outcome measures - Primary outcome measures was pain intensity while the secondary outcome measures were disability and lumbar range of motion - ROM. There were no adverse events occurred during the study. RESULTS: Fifty participants with non-specific low back pain (control group n=25; experimental group n=25) were randomized. There were significant between-group differences in pain scores (mean difference - MD 1.52; 95%CI -0.34 to 3.35), function disability (MD 8.14; 95%CI 6.5 to 9.96), Range of Motion (ROM) of lumbar flexion (MD -1.27; 95%CI -1.09 to -1.45), ROM of lumbar extension (MD -1.1; 95%CI -0.97 to -1.23), ROM of lumbar right side bending (MD 8.2; 95%CI 6.56 to 9.84) and ROM of lumbar left side bending (MD 10.4; 95%CI 8.81 to 11.99) in favour of the experimental group. CONCLUSION: Adding pulsed electromagnetic field to Conventional physical therapy Protocol yields superior clinical improvement in pain, functional disability, and lumbar ROM in patients with non-specific low back pain than Conventional physical therapy alone.


Sujet(s)
Lombalgie/physiopathologie , Champs électromagnétiques , Humains , Région lombosacrale/physiologie , Techniques de physiothérapie , Études prospectives , Amplitude articulaire
15.
Braz J Otorhinolaryngol ; 85(3): 282-289, 2019.
Article de Anglais | MEDLINE | ID: mdl-30583943

RÉSUMÉ

INTRODUCTION: In daily life biological systems are usually exposed to magnetic field forces at different intensities and frequencies, either directly or indirectly. Despite negative results, the therapeutic use of the low dose magnetic field has been found in recent studies. The effect of magnetic field forces on cochlear cells is not clear in the literature. OBJECTIVE: In our study, we first applied in vivo pulsed magnetic fields to laboratory rats to investigate the effects on cochlea with distortion product otoacoustic emission test followed by histopathological examinations. METHODS: Twelve rats were included in this study, separated into two groups as study group and control group. The rats in the study group were exposed to 40Hz pulsed magnetic field for 1h/day for 30 days; the hearing of the rats was controlled by otoacoustic emission test. Also, their cochleas were removed and histochemical examination was performed by Caspase-3, Caspase-9, and TUNEL methods. RESULTS: A statistically significant difference was determined (p<0.05) when the hearing thresholds of the groups obtained by using 5714Hz and 8000Hz stimuli were compared by Kruskal-Wallis test. A significant reaction was observed in the study group, especially in the outer ciliated cells during immunohistochemical examinations by using Caspase-3 and Caspase-9 methods. A significantly positive difference was determined in the study group, especially at the outer ciliated cells and the support cells of the corti organ, when compared to the control group (p<0.05) by the TUNEL method. CONCLUSION: According to the results of our study, the very low dose magnetic field, which is considered to be used for therapeutic purposes recently, can cause both auditory function defects and histopathologic damage in cochlear cells.


Sujet(s)
Cochlée/anatomopathologie , Champs électromagnétiques/effets indésirables , Cellules ciliées auditives externes/anatomopathologie , Animaux , Immunohistochimie , Mâle , Émissions otoacoustiques spontanées , Rats , Rat Wistar , Statistique non paramétrique
16.
Methods Mol Biol ; 1651: 205-212, 2017.
Article de Anglais | MEDLINE | ID: mdl-28801909

RÉSUMÉ

Gene expression can be modified by physical factors, such as heat, electricity and magnetic fields , and several types of ionizing and non-ionizing radiation. Promoter activation with extremely low-frequency electromagnetic fields is possible with an appropriate promoter, containing electromagnetic field response elements. Here, we describe how to examine promoter activation with extremely low-frequency electromagnetic fields, and we provide a step-by-step guide to the assembly of a solenoid suitable for promoter activation.


Sujet(s)
Champs électromagnétiques , Régulation de l'expression des gènes , Régions promotrices (génétique) , Transfection/méthodes , Animaux , Lignée cellulaire , Électroporation/méthodes , Vecteurs génétiques/génétique , Cellules HeLa , Humains , Luciferases/génétique , Souris , Souris de lignée BALB C
17.
Mol Biol (Mosk) ; 51(3): 524-533, 2017.
Article de Russe | MEDLINE | ID: mdl-28707669

RÉSUMÉ

The coupling between peptides and MHC-II proteins in the human immune system is not well understood. This work presents an evidence-based hypothesis of a guiding intermolecular force present in every human MHC-II protein (HLA-II). Previously, we examined the spatial positions of the fully conserved residues in all HLA-II protein types. In each one, constant planar patterns were revealed. These molecular planes comprise of amino acid groups of the same chemical species (for example, Gly) distributed across the protein structure. Each amino acid plane has a unique direction and this directional element offers spatial selectivity. Constant within all planes, too, is the presence of an aromatic residue possessing electrons in movement, leading the authors to consider that the planes generate electromagnetic fields that could serve as an attractive force in a single direction. Selection and attraction between HLA-II molecules and antigen peptides would, therefore, be non-random, resulting in a coupling mechanism as effective and rapid as is clearly required in the immune response. On the basis of planar projections onto the HLA-II groove, modifications were made by substituting the key residues in the class II-associated invariant chain peptide-a peptide with a universal binding affinity-resulting in eight different modified peptides with affinities greater than that of the unmodified peptide. Accurate and reliable prediction of MHC class II-binding peptides may facilitate the design of universal vaccine-peptides with greatly enhanced binding affinities. The proposed mechanisms of selection, attraction and coupling between HLA-II and antigen peptides are explained further in the paper.


Sujet(s)
Épitopes/métabolisme , Antigènes HLA/métabolisme , Oligopeptides/métabolisme , Séquence d'acides aminés/génétique , Acides aminés/composition chimique , Acides aminés/immunologie , Antigènes de différenciation des lymphocytes B/composition chimique , Antigènes de différenciation des lymphocytes B/immunologie , Sites de fixation , Épitopes/composition chimique , Épitopes/immunologie , Antigènes HLA/composition chimique , Antigènes HLA/immunologie , Antigènes d'histocompatibilité de classe II/composition chimique , Antigènes d'histocompatibilité de classe II/immunologie , Humains , Conformation moléculaire , Oligopeptides/composition chimique , Oligopeptides/immunologie , Liaison aux protéines
18.
Article de Anglais | MEDLINE | ID: mdl-26430395

RÉSUMÉ

BACKGROUND: Extremely low-frequency (50 Hz) electromagnetic field (ELF-EMF) is produced by electric power transmission lines and electronic devices of everyday use. Some phenomena are proposed as "first effects" of ELF-EMF: the discrete changes in the membrane potential and the increase of the calcium channel activity as well as the intracellular concentration of Ca(2+). Interaction of the scorpion alpha toxin with the sodium channel depends on the orientation of the charges and may be perturbed by changes in the membrane polarization. The toxin induces overexcitability in the nervous system and an increase in the neurotransmitters released with different consequences, mainly the paralysis of muscles. We assumed that the exposure to ELF-EMF 0.7 mT will change the effects of the insect selective scorpion alpha toxin (recombinant LqhαIT from Leiurus quinquestriatus hebraeus) at the level of the cercal nerve function, the synaptic transmission and on the level of entire insect organism. Taking into account the compensatory mechanisms in organisms, we tested in addition ten times higher ELF-EMF on whole insects. METHODS: Experiments were performed in vivo on cockroaches (Periplaneta americana) and in vitro - on isolated cockroach abdominal nerve cord with cerci. In biotests, the effects of LqhαIT (10(-8) M) were estimated on the basis of the insect ability to turn back from dorsal to ventral side. Three groups were compared: the control one and the two exposed to ELF-EMF - 0.7 and 7 mT. Bioelectrical activity of the cercal nerve and of the connective nerve that leaves the terminal abdominal ganglion was recorded using extracellular electrodes. LqhαIT (5 × 10(-8) M) induced modifications of neuronal activity that were observed in the control cockroach preparations and in the ones exposed to ELF-EMF (0.7 mT). The exposure to ELF-EMF was carried out using coils with a size appropriate to the examined objects. RESULTS: The exposure to ELF-EMF (0.7 mT) modified the effects of LqhαIT (5 × 10(-8) M) on activity of the cercal nerve and of the connective nerve. We observed a decrease of the toxin effect on the cercal nerve activity, but the toxic effect of LqhαIT on the connective nerve was increased. Biotests showed that toxicity of LqhαIT (10(-8) M) on cockroaches was reduced by the exposure to ELF-EMF (0.7 and 7 mT). CONCLUSIONS: The exposure to 50 Hz ELF-EMF modified the mode of action of the anti-insect scorpion alpha toxin LqhαIT at cellular level of the cockroach nervous system and in biotests. Toxin appeared as a usefull tool in distinguishing between the primary and the secondary effects of ELF-EMF.

19.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 21: 1-11, Oct. 20, 2015. ilus, graf
Article de Anglais | VETINDEX | ID: vti-28012

RÉSUMÉ

Background Extremely low-frequency (50 Hz) electromagnetic field (ELF-EMF) is produced by electric power transmission lines and electronic devices of everyday use. Some phenomena are proposed as first effects of ELF-EMF: the discrete changes in the membrane potential and the increase of the calcium channel activity as well as the intracellular concentration of Ca 2+ . Interaction of the scorpion alpha toxin with the sodium channel depends on the orientation of the charges and may be perturbed by changes in the membrane polarization. The toxin induces overexcitability in the nervous system and an increase in the neurotransmitters released with different consequences, mainly the paralysis of muscles. We assumed that the exposure to ELF-EMF 0.7 mT will change the effects of the insect selective scorpion alpha toxin (recombinant LqhIT from Leiurus quinquestriatus hebraeus) at the level of the cercal nerve function, the synaptic transmission and on the level of entire insect organism. Taking into account the compensatory mechanisms in organisms, we tested in addition ten times higher ELF-EMF on whole insects.Methods Experiments were performed in vivo on cockroaches (Periplaneta americana) and in vitro on isolated cockroach abdominal nerve cord with cerci. In biotests, the effects of LqhIT (10 8 M) were estimated on the basis of the insect ability to turn back from dorsal to ventral side. Three groups were compared: the control one and the two exposed to ELF-EMF 0.7 and 7 mT. Bioelectrical activity of the cercal nerve and of the connective nerve that leaves the terminal abdominal ganglion was recorded using extracellular electrodes. LqhIT (5 × 10 8 M) induced modifications of neuronal activity that were observed in the control cockroach preparations and in the ones exposed to ELF-EMF (0.7 mT). The exposure to ELF-EMF was carried out using coils with a size appropriate to the examined objects.Results The exposure to ELF-EMF (0.7 mT) modified the effects of LqhIT (5 × 108 M) on activity of the cercal nerve and of the connective nerve. We observed a decrease of the toxin effect on the cercal nerve activity, but the toxic effect of LqhIT on the connective nerve was increased. Biotests showed that toxicity of LqhIT (10 8 M) on cockroaches was reduced by the exposure to ELF-EMF (0.7 and 7 mT).Conclusions The exposure to 50 Hz ELF-EMF modified the mode of action of the anti-insect scorpion alpha toxin LqhIT at cellular level of the cockroach nervous system and in biotests. Toxin appeared as a usefull tool in distinguishing between the primary and the secondary effects of ELF-EMF.(AU)


Sujet(s)
Animaux , Animaux venimeux , Venins de scorpion , Champs électromagnétiques/effets indésirables , Tests de toxicité/médecine vétérinaire
20.
Genet Mol Biol ; 38(2): 227-30, 2015 May.
Article de Anglais | MEDLINE | ID: mdl-26273227

RÉSUMÉ

Several studies of the physiological responses of different organisms exposed to extremely low-frequency electromagnetic fields (ELF-EMF) have been described. In this work, we report the minimal effects of in situ exposure to ELF-EMF on the global protein expression of Chromobacterium violaceum using a gel-based proteomic approach. The protein expression profile was only slightly altered, with five differentially expressed proteins detected in the exposed cultures; two of these proteins (DNA-binding stress protein, Dps, and alcohol dehydrogenase) were identified by MS/MS. The enhanced expression of Dps possibly helped to prevent physical damage to DNA. Although small, the changes in protein expression observed here were probably beneficial in helping the bacteria to adapt to the stress generated by the electromagnetic field.

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