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La estimulación magnética transcraneal (EMT) es una técnica no invasiva que consiste en la utilización de campos magnéticos para estimular a las neuronas de la corteza cerebral. Si bien la electricidad se ha pretendido emplear previamente en el campo de la medicina, la historia de la EMT se remonta al descubrimiento de la inducción electromagnética, por Faraday, en el siglo XIX. Sin embargo, no fue hasta la década de 1980 cuando Anthony Barker, en la Universidad de Sheffield, desarrolló el primer dispositivo de EMT. La EMT funciona mediante una bobina colocada en el cuero cabelludo, la cual produce un campo magnético que puede atravesar el cráneo y estimular las neuronas corticales. La intensidad y la frecuencia del campo magnético pueden ajustarse para dirigirse a zonas específicas del cerebro y producir efectos excitatorios e inhibitorios. Los principios de la EMT se basan en el concepto de neuroplasticidad, que se refiere a la capacidad del cerebro para cambiar y adaptarse en respuesta a nuevas experiencias y estímulos. Al estimular las neuronas del cerebro con la EMT, es posible inducir cambios en la actividad neuronal y la conectividad, lo que a su vez puede provocar cambios cognitivos y en el estado de ánimo.
Transcranial magnetic stimulation (TMS) is a noninvasive technique that uses magnetic fields to stimulate neurons in the cerebral cortex. While electricity has previously been intended to be used in the medical field, the history of TMS dates back to the discovery of electromagnetic induction by Faraday in the 19th century. However, it was not until the 1980s when Anthony Barker developed the first TMS device at the University of Sheffield. TMS works by means of a coil placed against the scalp, thereby producing a magnetic field. This magnetic field can pass through the skull and stimulate cortical neurons. The intensity and frequency of the magnetic field can be adjusted to target specific areas of the brain and produce excitatory and inhibitory effects. The principles of TMS are based on the concept of neuroplasticity, which refers to the brain's ability to change and adapt in response to new experiences and stimuli. By stimulating neurons in the brain with TMS, it is possible to cause changes in neuronal activity and connectivity, which in turn can lead to cognitive and mood changes.
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Abstract Background: There have been scattered reports indicating the possibility that applied magnetic fields can lower human blood viscosity, which has been considered as encouraging for decreasing blood pressure as a result of greater fluidity. Additional motivation comes from partial studies in animals showing some response of vascular variables to magnetic fields. Recently developed FeNbB magnets enable topical application to appropriate sites of much stronger permanent magnetic fields than previously available. Objectives: To establish whether powerful magnetic fields permanently applied along important arteries of the human body can lower blood pressure and, if so, to what extent. Methods: Ambulatory blood pressure tests were performed on 70 patients, half of them wearing real magnets, while the other 35 patients were wearing a similar placebo. Magnets or placebo devices were assigned at random. Each patient underwent two consecutive ambulatory 24-hour blood pressure (BP) tests; the first without a device and the second one with a device. Results: Results were compiled and analyzed only after the last measurement was completed. Individual responses, average values, standard deviations, information content, and Student's t test showed that no difference was found between measurements in either group. Conclusion: Permanent strong magnetic fields applied along the main arteries of the human body do not alter blood pressure. This was observed both in statistical terms and in individuals as well.
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Magnetic fields in biological systems is a promising research field; however, their application for microalgae has not been fully exploited. This work aims to measure the enzymatic activity and non-enzymatic activity of two microalgae species in terms of superoxide dismutase (SOD), catalase (CAT), and carotenoids, respectively, in response to static magnetic fields-induced stress. Two magnet configurations (north and south) and two exposure modes (continuous and pulse) were applied. Two microalgae species were considered, the Scenedesmus obliquus and Nannochloropsis gaditana. The SOD activity increased by up to 60% in S. obliquus under continuous exposure. This trend was also found for CAT in the continuous mode. Conversely, under the pulse mode, its response was hampered as the SOD and CAT were reduced. For N. gaditana, SOD increased by up to 62% with the south configuration under continuous exposure. In terms of CAT, there was a higher activity of up to 19%. Under the pulsed exposure, SOD activity was up to 115%. The CAT in this microalga was increased by up to 29%. For N. gaditana, a significant increase of over 40% in violaxanthin production was obtained compared to the control, when the microalgae were exposed to SMF as a pulse. Depending on the exposure mode and species, this methodology can be used to produce oxidative stress and obtain an inhibitory or enhanced response in addition to the significant increase in the production of antioxidant pigments.
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Microalgas , Animais , Campos Magnéticos , Estresse OxidativoRESUMO
BACKGROUND: There has been an increasing interest in researching on the effects of extremely low-frequency magnetic fields on living systems. The mechanism of action of extremely low-frequency magnetic fields on organisms has not been established. One of the hypotheses is related to induce changes in oxidative balance. In this study, we measured the effects of chronic unpredictable mild stress induced-oxidative balance of rat's brain exposed to extremely low-frequency magnetic fields. METHODS: A first experiment was conducted to find out if 14 days of chronic unpredictable mild stress caused oxidative unbalance in male Wistar rat's brain. Catalase activity, reduced glutathione concentration, and lipoperoxidation were measured in cerebrum and cerebellum. In the second experiment, we investigate the effects of 7 days extremely low-frequency magnetic fields exposure on animals stressed and unstressed. RESULTS: The main results obtained were a significant increase in the catalase activity and reduced glutathione concentration on the cerebrum of animals where the chronic unpredictable mild stress were suspended at day 14 and then exposed 7 days to extremely low-frequency magnetic fields. Interestingly, the same treatment decreases the lipoperoxidation in the cerebrum. The stressed animals that received concomitant extremely low frequency magnetic fields exposure showed an oxidative status like stressed animals by 21 days. Thus, no changes were observed on the chronic unpredictable mild stress induced-oxidative damage in the rat's cerebrum by the extremely low-frequency magnetic field exposure together with chronic unpredictable mild stress. CONCLUSIONS: The extremely low-frequency electromagnetic field exposure can partially restore the cerebrum antioxidant system of previously stressed animals.
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Encéfalo/metabolismo , Campos Eletromagnéticos , Estresse Oxidativo/fisiologia , Estresse Psicológico/metabolismo , Estresse Psicológico/terapia , Animais , Masculino , Ratos , Ratos Wistar , Estresse Psicológico/psicologiaRESUMO
The problem of finding covariance matrices that remain constant in time for arbitrary multi-dimensional quadratic Hamiltonians (including those with time-dependent coefficients) is considered. General solutions are obtained.
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In this work, we studied the impact of magnetic nanoparticles (MNPs) interactions with HeLa cells when they are exposed to high frequency alternating magnetic field (AMF). Specifically, we measured the nanobiomechanical properties of cell interfaces by using atomic force microscopy (AFM). Magnetite (Fe3O4) MNPs were synthesized by coprecipitation and encapsulated with silica (SiO2): Fe3O4@SiO2and functionalized with amino groups (-NH2): Fe3O4@SiO2-NH2, by sonochemical processing. HeLa cells were incubated with or without MNPs, and then exposed to AMF at 37 °C. A biomechanical analysis was then performed through AFM, providing the Young's modulus and stiffness of the cells. The statistical analysis (p < 0.001) showed that AMF application or MNPs interaction modified the biomechanical behavior of the cell interfaces. Interestingly, the most significant difference was found for HeLa cells incubated with Fe3O4@SiO2-NH2and exposed to AMF, showing that the local heat of these MNPs modified their elasticity and stiffness.
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Fenômenos Biomecânicos/fisiologia , Fenômenos Fisiológicos Celulares/fisiologia , Nanopartículas de Magnetita/química , Dióxido de Silício/química , Módulo de Elasticidade/fisiologia , Células HeLa , Humanos , Microscopia de Força Atômica , Nanotecnologia , Propriedades de SuperfícieRESUMO
The extremophilic bacterium Deinococcus radiodurans displays an extraordinary ability to withstand lethal radiation effects, due to its complex mechanisms for both proteome radiation protection and DNA repair. Published results obtained recently at this laboratory show that D. radiodurans submitted to ionizing radiation results in its DNA being shattered into small fragments which, when exposed to a "static electric field' (SEF), greatly decreases cell viability. These findings motivated the performing of D. radiodurans exposed to gamma radiation, yet exposed to a different exogenous physical agent, "static magnetic fields" (SMF). Cells of D. radiodurans [strain D.r. GY 9613 (R1)] in the exponential phase were submitted to 60Co gamma radiation from a gamma cell. Samples were exposed to doses in the interval 0.5-12.5 kGy, while the control samples were kept next to the irradiation setup. Exposures to SMF were carried out with intensities of 0.08 T and 0.8 T delivered by two settings: (a) a device built up at this laboratory with niobium magnets, delivering 0.08 T, and (b) an electromagnet (Walker Scientific) generating static magnetic fields with intensities from 0.1 to 0.8 T. All samples were placed in a bacteriological incubator at 30 °C for 48 h, and after incubation, a counting of colony forming units was performed. Two sets of cell surviving data were measured, each in triplicate, obtained in independent experiments. A remarkable similarity between the two data sets is revealed, underscoring reproducibility within the 5% range. Appraisal of raw data shows that exposure of irradiated cells to SMF substantially increases their viability. Data interpretation strongly suggests that the increase of D. radiodurans cell viability is a sole magnetic physical effect, driven by a stochastic process, improving the efficiency of the rejoining of DNA fragments, thus increasing cell viability. A type of cut-off dose is identified at 10 kGy, above which the irradiated cellular system loses recovery and the cell survival mechanism collapses.
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Deinococcus/citologia , Deinococcus/efeitos da radiação , Raios gama , Campos Magnéticos , Sobrevivência Celular/efeitos da radiação , Fragmentação do DNA/efeitos da radiação , Deinococcus/genéticaRESUMO
Magnetic field (MF) can interact with the metabolism of microalgae and has an effect (positive or negative) on the synthesis of molecules. In addition to MF, the use of pentose as a carbon source for cultivating microalgae is an alternative to increase carbohydrate yield. This study aimed at evaluating the MF application on the mixotrophic culture of Chlorella minutissima in order to produce carbohydrates. MF of 30 mT was generated by ferrite magnets and applied diurnally for 12 days. The addition of 5% pentose, MF application of 30 mT, and nitrogen concentration reduced (1.25 mM of KNO3) was the best conditions to obtain higher carbohydrate concentrations. MF application of 30 mT increased biomass and carbohydrate contents in 30% and 163.1%, respectively, when compared with the assay without MF application. The carbohydrate produced can be used for bioethanol production.
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Carboidratos/biossíntese , Chlorella/crescimento & desenvolvimento , Chlorella/metabolismo , Técnicas de Cultura/métodos , Campos Magnéticos , Biomassa , Etanol/metabolismoRESUMO
Resumen Introducción: la demanda de energía eléctrica va de la mano del aumento de la población, por lo que para satisfacerla se debe asegurar la capacidad de generación eléctrica, esto incentivaría la construcción de plantas térmicas; aumentando los trabajadores expuestos a los peligros de termoeléctricas. Esta revisión tiene como fin identificar cuáles riesgos y peligros en termoeléctricas han sido estudiadas en el mundo durante el periodo 20072017. Objetivo: identificar, a través de una revisión bibliográfica, los principales peligros a que están expuestos los trabajadores de termoeléctricas. Materiales y métodos: se realizó una revisión sistemática teniendo en cuenta las recomendaciones de la guía PRISMA, se tuvieron en cuenta estudios acerca de los factores de riesgos a los que se exponen el personal de operaciones de centrales térmicas; para la búsqueda se establecieron dos algoritmos con descriptores DeCS y MeSH en las bases de datos Scopus, Pubmed, Scient Direct y Google académico, encontrándose 21 publicaciones que cumplían con los criterios de inclusión. Resultados: los peligros más relevantes para los trabajadores en termoeléctricas son físicos, ergonómicos, químicos, biológicos y psicosociales. Conclusión: los trabajadores de termoeléctricas están expuestos a varios peligros que pueden aumentar el riesgo de ocasionarles enfermedades respiratorias, musculoesqueleticas, pérdida de capacidad auditiva, cáncer, leucemia y su variedad, pericarditis, Alzheimer, Parkinson, daño genético y celular; también se pudo evidenciar que el efecto en la salud por exposición en campos magnéticos requiere de estudios de más profundidad.
Abstract Introduction: the demand for electric power, goes hand in hand with the population increasing, to satisfy it, the power generation capacity must be ensured, this would encourage the construction of thermal plants; increasing the exposition of workers to the thermoelectric plant dangers. This review aims to identify which risks and dangers in thermoelectric plants have been studied in the world for the period 2007-2017. Objective: identify the main hazards to which thermoelectric workers are exposed through a literature review. Materials and methods: a systematic review was carried out taking into account the recommendations of the PRISMA guide, studies were taken into account about the risk factors to which thermal power plant operations personnel are exposed; Two algorithms with DeCS and MeSH descriptors were established in the Scopus, PubMed, Scient Direct and Google academic databases, with 21 publications meeting the inclusion criteria. Results: the most relevant hazards for thermoelectric workers are physical, ergonomic, chemical, biological and psychosocial. Conclusion: thermoelectric workers are exposed to various hazards that may increase the risk of respiratory, musculoskeletal, hearing loss, cancer, leukemia and its variety, pericarditis, Alzheimer's, Parkinson's, genetic and cellular damage; It could also be evidenced that the effect on health by exposure in magnetic fields requires more in-depth studies.
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Humanos , Centrais Elétricas , Riscos Ocupacionais , Fatores de Risco , Morbidade , Saúde Ocupacional , Gases de Efeito Estufa , Campos MagnéticosRESUMO
In order to run a series of in vitro studies on the effect of extremely low-frequency magnetic fields on cell cultures, developing and characterizing an appropriate exposure system is required. The present design is based on a two-shielded Lee-Whiting coils system. The circular design was chosen because its axial symmetry allowed for both reducing simulation unknowns and measurement points during the characterization, and additionally made the machining of the parts easier. The system can generate magnetic flux densities (B fields) up to 1 mT root-mean-square amplitude (rms) with no active cooling system in the incubator, and up to 3 mTrms with it. The double-wrapped windings with twisted pairs allow for the use of each set of coils either as exposure or control with no detectable parasitic B field in the control. The artifacts have also been analyzed; the B field in the center of the sham control chamber is about 1 µTrms for a maximum of 3 mTrms in the exposure chamber, the parasitic incident electric fields are less than 1 V/m, the temperature difference between sham and exposure chamber is less than or equal to 0.2 °C, and the typical vibration difference between sham and exposure is less than 0.1 m/s2 . © 2020 Bioelectromagnetics Society.
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Campos Eletromagnéticos/efeitos adversos , Exposição à Radiação/análise , Radiometria/instrumentação , Desenho de EquipamentoRESUMO
Silicosis is a pneumoconiosis caused by inhaled crystalline silica microparticles, which trigger inflammatory responses and granuloma formation in pulmonary parenchyma, thus affecting lung function. Although systemic administration of mesenchymal stromal cells (MSCs) ameliorates lung inflammation and attenuates fibrosis in experimental silicosis, it does not reverse collagen deposition and granuloma formation. In an attempt to improve the beneficial effects of MSCs, magnetic targeting (MT) has arisen as a potential means of prolonging MSC retention in the lungs. In this study, MSCs were incubated with magnetic nanoparticles and magnets were used for in vitro guidance of these magnetized MSCs and to enhance their retention in the lungs in vivo. In vitro assays indicated that MT improved MSC transmigration and expression of chemokine receptors. In vivo, animals implanted with magnets for 48 hours had significantly more magnetized MSCs in the lungs, suggesting improved MSC retention. Seven days after magnet removal, silicotic animals treated with magnetized MSCs and magnets showed significant reductions in static lung elastance, resistive pressure, and granuloma area. In conclusion, MT is a viable technique to prolong MSC retention in the lungs, enhancing their beneficial effects on experimentally induced silicosis. MT may be a promising strategy for enhancing MSC therapies for chronic lung diseases.
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Pulmão/patologia , Magnetismo/métodos , Células-Tronco Mesenquimais/patologia , Nanopartículas/metabolismo , Silicose/terapia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Silicose/fisiopatologiaRESUMO
Los neonatos pretérminos nacen con inmadurez en los órganos, lo que lleva al compromiso del sistema inmunológico. Los campos electromagnéticos afectan la producción de melatonina a niveles bajos de exposición. Estos niños necesitan equipamiento médico las 24 horas del día para su recuperación, por lo que están expuestos a los campos magnéticos durante todo el tiempo que se encuentren en la Unidad de Terapia Intensiva. El objetivo fue medir los niveles de campo magnético que se generan alrededor de cada una de las incubadoras utilizando un gaussímetro y comparar los resultados con las recomendaciones de la Comisión Internacional para la Protección contra las Radiaciones No Ionizantes de 2010 y la norma de la International Electrotechnical Commission (IEC) IEC 60601-1-2:2004. En 11 neonatos internados, los valores de radiación se encontraban dentro de los recomendados, pero existía interferencia electromagnética por problemas de disposición de los equipos en el área.
Preterm infants are born with immature organs, thus affecting the immune system. Electromagnetic fields influence melatonin production with low exposure levels. These infants require medical equipment 24/7 to recover, so they are constantly exposed to magnetic fields during their stay in the Intensive Care Unit. Our objective was to measure magnetic field levels generated around each incubator using a gauss meter and compare our results to the 2010 recommendations by the International Commission on Non-Ionizing Radiation Protection and the IEC 60601-1-2:2004 standard by the International Electrotechnical Commission (IEC). Among 11 hospitalized newborn infants, radiation was found within the recommended limits, but there was electromagnetic interference resulting from medical equipment layout problems in the unit.
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Humanos , Masculino , Feminino , Recém-Nascido , Campos Magnéticos/efeitos adversos , Recém-Nascido Prematuro , Equipamentos e Provisões , Medição de Níveis de Água/análise , Incubadoras , Unidades de Terapia Intensiva , Concentração Máxima Permitida , MelatoninaRESUMO
Preterm infants are born with immature organs, thus affecting the immune system. Electromagnetic fields influence melatonin production with low exposure levels. These infants require medical equipment 24/7 to recover, so they are constantly exposed to magnetic fields during their stay in the Intensive Care Unit. Our objective was to measure magnetic field levels generated around each incubator using a gauss meter and compare our results to the 2010 recommendations by the International Commission on Non-Ionizing Radiation Protection and the IEC 60601-1-2:2004 standard by the International Electrotechnical Commission (IEC). Among 11 hospitalized newborn infants, radiation was found within the recommended limits, but there was electromagnetic interference resulting from medical equipment layout problems in the unit.
Los neonatos pretérminos nacen con inmadurez en los órganos, lo que lleva al compromiso del sistema inmunológico. Los campos electromagnéticos afectan la producción de melatonina a niveles bajos de exposición. Estos niños necesitan equipamiento médico las 24 horas del día para su recuperación, por lo que están expuestos a los campos magnéticos durante todo el tiempo que se encuentren en la Unidad de Terapia Intensiva. El objetivo fue medir los niveles de campo magnético que se generan alrededor de cada una de las incubadoras utilizando un gaussímetro y comparar los resultados con las recomendaciones de la Comisión Internacional para la Protección contra las Radiaciones No Ionizantes de 2010 y la norma de la International Electrotechnical Commission (IEC) IEC 60601-1-2:2004. En 11 neonatos internados, los valores de radiación se encontraban dentro de los recomendados, pero existía interferencia electromagnética por problemas de disposición de los equipos en el área.
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Exposição Ambiental/estatística & dados numéricos , Unidades de Terapia Intensiva Neonatal , Campos Magnéticos , Exposição Ambiental/análise , Exposição Ambiental/prevenção & controle , Exposição Ambiental/normas , Humanos , Incubadoras para Lactentes , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal/normas , Terapia Intensiva Neonatal/normas , Campos Magnéticos/efeitos adversos , Guias de Prática Clínica como AssuntoRESUMO
Magnetic fields (MFs) have been used as an external stimulus to increase cell proliferation in chondrocytes and extracellular matrix (ECM) synthesis of articular cartilage. However, previously published studies have not shown that MFs are homogeneous through cell culture systems. In addition, variables such as stimulation times and MF intensities have not been standardized to obtain the best cellular proliferative rate or an increase in molecular synthesis of ECM. In this work, a stimulation device, which produces homogeneous MFs to stimulate cell culture surfaces was designed and manufactured using a computational model. Furthermore, an in vitro culture of primary rat chondrocytes was established and stimulated with two MF schemes to measure both proliferation and ECM synthesis. The best proliferation rate was obtained with an MF of 2 mT applied for 3 h, every 6 h for 8 days. In addition, the increase in the synthesis of glycosaminoglycans was statistically significant when cells were stimulated with an MF of 2 mT applied for 5 h, every 6 h for 8 days. These findings suggest that a stimulation with MFs is a promising tool that could be used to improve in vitro treatments such as autologous chondrocyte implantation, either to increase cell proliferation or stimulate molecular synthesis. Bioelectromagnetics. 2020;41:41-51 © 2019 Bioelectromagnetics Society.
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Cartilagem Articular/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Campos Magnéticos/efeitos adversos , Animais , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Células Imobilizadas , Simulação por Computador , Glicosaminoglicanos/química , Ratos , Ratos Wistar , Propriedades de Superfície , Temperatura , Fatores de TempoRESUMO
This study aimed at evaluating whether a magnetic field (MF) affects the growth of Spirulina sp. when applied to it at different exposure times in indoor and outdoor culture systems. The effects of MF on chlorophyll content, medium consumption and protein profile were also investigated. In raceway tanks, a 25â¯mT MF was applied for 24â¯h or for 1â¯hâ¯d-1. MF for 24â¯h to outdoor assays increased biomass concentration and chlorophyll-a content besides altering the protein profile. Outdoor Spirulina growth was higher (â¼3.65â¯gâ¯L-1) than the growth found in indoor assays (â¼1.80â¯gâ¯L-1), while nitrogen and phosphorus consumption was not enhanced by the application of MF. This is the first study that investigated the influence of MF on outdoor microalga assays, and the results showed that MF affected the metabolism of Spirulina cultured in raceways, especially when it was grown outdoors in uncontrolled environmental conditions.
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Campos Magnéticos , Spirulina , Biomassa , Nitrogênio , FósforoRESUMO
Static or modulated magnetic fields (MF) may interact with the biological system and affect the metabolism of microorganisms, such as their photosynthetic capacity or synthesis of carbohydrates. Their effects on microorganisms, which can be classified into inhibiting, stimulating and null, may be interpreted as the result of stress that cells undergo, thus, leading to responses through the same mechanisms. Biological effects of exposure to magnetic forces depend on magnetic intensity, frequency and exposure time. Modifications in these parameters may enhance product formation. Effects differ according to the form and application of MF characteristic parameters. Magnetic treatments have the advantages of being convenient and non-toxic, having low running cost, emitting no secondary pollution, enabling wide application and being easily shielded. MF application to the cultivation of microalgae, to improve the production of finished biomolecules, is a simple, inexpensive and powerful process. However, bioeffects of MF on microalgae need to be further investigated because there have currently been very few available reports in the literature. Thus, studies which aim at optimizing parameters involved in MF application must be developed in order to obtain the best conditions for the production of molecules with high economic potential.
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Bioengenharia/métodos , Microalgas/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Fenômenos Magnéticos , Microalgas/metabolismo , FotossínteseRESUMO
This chapter provides a review of different advanced methods that help to increase the success rate of a crystallization project, by producing larger and higher quality single crystals for determination of macromolecular structures by crystallographic methods. For this purpose, the chapter is divided into three parts. The first part deals with the fundamentals for understanding the crystallization process through different strategies based on physical and chemical approaches. The second part presents new approaches involved in more sophisticated methods not only for growing protein crystals but also for controlling the size and orientation of crystals through utilization of electromagnetic fields and other advanced techniques. The last section deals with three different aspects: the importance of microgravity, the use of ligands to stabilize proteins, and the use of microfluidics to obtain protein crystals. All these advanced methods will allow the readers to obtain suitable crystalline samples for high-resolution X-ray and neutron crystallography.
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Cristalização/métodos , Cristalografia/métodos , Microfluídica/métodos , Proteínas/ultraestrutura , Sefarose/química , Sulfato de Amônio/química , Precipitação Química , Cristalografia/instrumentação , Campos Eletromagnéticos , Géis , Microfluídica/instrumentação , Difração de Nêutrons , Polietilenoglicóis/química , Proteínas/química , Solubilidade , Ausência de Peso , Difração de Raios XRESUMO
Inserido no paradigma da transdisciplinaridade, o presente trabalho foi desenvolvido em etapas, com os seguintes objetivos: a) Construir um dispositivo com base de metal não magnético para ímãs permanentes, visando à geração de um Campo Magnético Estático (CME) ou de um Campo Magnético Compensado (CMC); b) Expor culturas de células mesenquimais a um CME e a um CMC, ou a nenhum campo (controle); c) Analisar a influência destes campos na viabilidade e proliferação celular e nos casos em que houve alteração em pelo menos um destes parâmetros, utilizar a análise proteômica como ferramenta para a compreensão dos mecanismos envolvidos. O dispositivo foi construído utilizando aço inoxidável, capaz de gerar dois tipos de Campos Magnéticos: Compensado (CMC) com intensidade de aproximadamente 0 mT e Estático (CME) com intensidade média de 165 mT. Estes campos foram aplicados a culturas de células mesenquimais de medula óssea de camundongos AJ (MSC/AJ), nos períodos de 0, 24, 48, 72 e 96 h (CMC) e 24 h (CME). Os efeitos sobre a proliferação e a viabilidade foram avaliados por método de contagem manual de células com marcação por azul de tripan. A análise proteômica foi realizada para os experimentos com CMC, com o objetivo de descrever as proteínas envolvidas nas alterações encontradas. A exposição ao CMC tendeu a reduzir a proliferação das células de medula óssea MSC/AJ em relação ao controle em 96 h, porém sem diferença significativa, o que poderia estar relacionado a proteínas que inibem a transcrição, como a Forkhead box protein P2 Foxp2. Este mesmo campo aumentou a viabilidade celular em relação ao baseline para todos os tempos experimentais, o que poderia estar relacionado a proteínas relacionadas à ligação ao Ca+2. Esses mecanismos, entretanto, precisam ser estudados mais profundamente para que possam ser comprovados ou não. Já a exposição ao CME levou a uma tendência à diminuição da proliferação e viabilidade celular em relação ao grupo controle, embora sem diferenças significativas, provavelmente por conta do tamanho amostral e tempo de avaliação (24 h).(AU)
Inserted in the transdisciplinarity paradigm, the present work was developed by steps with the following aims: a) To build a device of non-magnetic metal to hold permanent magnets for the generation of a Static Magnetic Field (SMF) or a Compensated Magnetic Field (CMF); b) To expose mesenchimal cells to the SMF and to CMF or to none of the fields (control); c) To analyze the influence of these fields on cell viability and cell proliferation and in the case where it occurred alteration in at least one of these parameters, to use proteomics as a tool for the comprehension of the involved mechanisms. The device was built in stainless steel, able to generate two kinds of Magnetic Fields: Compesated (CMF) with an intensity of nearly zero mT and Static (SMF) with a mean intensity of 165 mT. These fields were applied to bone marrow mesenchimal cell cultures from AJ mice (MSC/AJ), for 0, 24, 48, 72 and 96 h (CMF) and 24 h (SMF) periods. The effects on the proliferation and viability were assessed by tripan blue dying and manual counting of the cells. Proteomics was done for the experiments with CMF, aiming to describe the involved proteins on found alterations. The exposition to CMF tends to reduce the bone marrow cell proliferation of MSC/AJ in relation to control in 96 h, but with no significant difference, which may be related to proteins that inhibit the transcription, like Forkhead box protein P2 Foxp2. This very field raised the cell viability in relation to the baseline for all the experimental times that could be related to proteins connected to Ca2+ binding. However, these mechanisms need more experiments, so they can be confirmed or not. The exposition to the SMF tends to decrease both cell proliferation and viability in relation to the control group, although with no significant difference, probably because of the sample number and the exposition time (24h).(AU)