Investigation of the effects of static magnetic field on apoptosis in bone marrow stem cells of rat

This research was carried out to evaluate the influence of static magnetic field on the rate of apoptosis in bone marrow stem cells (BMSCs) of rats. Extracted cells were suspended in αMEM as a culture media for 48 h. After that, cells were exposed to 15 mT static magnetic field (SMF) for 5 h, incessantly with or without FeCl₂. The rate of apoptosis was then assessed via flow cytometery. The results showed that either treatment with FeCl₂ or exposure to SMF enhanced the rate of apoptotic cells. Moreover, cells that were treated simultaneously with FeCl₂ and SMF have higher rate of apoptosis. An increase in apoptosis by 26.5% was induced by SMF alone and an increase in apoptosis by 28.2% was induced by a combination of FeCl₂ and SMF, compared to their corresponding controls. The results recommended that the effects of SMF on apoptosis may be related to increment of the number of free radicals in the cells.     

Application of magnetic field and iron in order to change medicinal products of <Emphasis Type="Italic">Ocimum basilicum</Emphasis>

In the present research, the effects of static magnetic field, with or without iron on the growth, the activity of certain enzymes (like polyphenol oxidase and phenyle alanine ammonialyase), the content of phenolic compounds and the essential oil composition of sweet basil (Ocimum basilicum) were studied. Treatment of plants with static magnetic field with or without iron led to decrease of the growth of plants as well as decrease in the activity of phenyle alanine ammonialyase and of phenolic compounds content. In addition in those plants exposed to magnetic field the amount of essential oils, notably of methyl chavicol, was increased. Exposure of plants to the magnetic field decreased the activity of polyphenol oxidase, whereas treatment of plants with iron when exposed to magnetic field increased polyphenol oxidase activity. In this group the content of essential oil was reduced.     

50 Hz alternating extremely low frequency magnetic fields affect excitability,firing and action potential shape through interaction with ionic channels in snail neurones

In spite of growing concern about the influence of magnetic fields on biological systems, the interaction between extremely low frequency magnetic field (ELF magnetic fields) and biological structures at the cellular level remains obscure. The aim of this study was to investigate if 50 Hz magnetic fields could have an effect on the neuronal excitability and firing responses. Under Current-Clamp condition, exposure to 50 Hz ELF magnetic fields at 2 mT or 0.8 mT intensities resulted in an increase in the peak amplitude of action potential and after hyperpolaization potential in a time dependent manner. Both magnetic field intensities decreased also the firing frequency and the duration of action potential. Taken together, these data suggest that 50 Hz ELF magnetic fields at 2 mT or 0.8 mT intensities may change the electrophysiological behavior of neuronal cells and underlying ion channel currents.     

Radical Scavengers Suppress Low Frequency EMF Enhanced Proliferation in Cultured Cells and Stress Effects in Higher Plants

Summary In previous publications, we reported that sinusoidal varying magnetic fields (SVMF) modify the activity and dynamics of the malignancy marker adenosine deaminase, and enhance the proliferation of chick embryo fibroblasts (CEF). While the SVMF examined by us (50, 60 & 100 Hz / 0.06–0.7 mT) were all below kT, they may have the potential of altering chemical processes in which excited radicals are involved. We tested this hypothesis in two experimental systems: CEF in culture and Spirodela oligorrhiza (Lemnaceae) (a small aquatic plant, commonly known as Duckweed). CEF were exposed to SVMF of 100 Hz/0.7 mT for 24 h. The addition of the exogenous radical scavengers catalase, superoxide dismutase or vitamin E to the cells during exposure significantly suppressed enhancement of cell proliferation caused by the field (by 79, 67 and 82%, respectively, as evaluated by the MTT colorimetric assay). ¹⁵N NMR analysis of Duckweed plants fed by ¹⁵N-labeled ammonium chloride and exposed to SVMF at 60 and 100 Hz/0.7 mT for 24 h, revealed augmented alanine production. Alanine did not accumulate in the absence of SVMF. The addition of vitamin C, a radical scavenger, reduced alanine production by 82%. Exposure to SVMF resulted in specific metabolic stress effects in Duckweed plants and enhanced proliferation of CEF. In both cases, it is suggested that free radicals are involved.     

Clinical aspects of static magnetic field effects on circulatory system

Increased knowledge of the magnetic field influence on hemodynamic function may have significant therapeutic potential and possible health effects. For example, magnetic field therapy using moderate intensity static magnetic fields (SMF) in the mT range (in particular, 1–600 mT) could be useful for circulatory diseases, including ischemic pain, inflammation, and hypertension, primarily due to the modulation of blood flow and/or blood pressure through the nervous system. We suggested that the mechanisms of SMF effects on the circulatory system in the mT range could be mediated by suppressing or enhancing the action of biochemical effectors, thereby inducing homeostatic effects biphasically. The potent mechanisms of SMF effects have often been linked to nitric oxide pathway, Ca²⁺-dependent pathway, sympathetic nervous system (e.g., BRS and the action of sympathetic agonists or antagonists), and neurohumoral regulatory system (e.g., production and secretion of angiotensin II and aldosterone). Thus, this review mainly focuses on the experimental studies of SMF effects on the circulatory system in animals and may provide the physiological basis for future clinical investigations of SMF therapy.     

Occupational risk from static magnetic fields of MRI scanners

The health care staff operating magnetic resonance imaging (MRI) scanners are exposed to static magnetic field of significant spatial heterogenity and high level of flux density—usually existing permanently during the shift. The personnel can also be exposed to pulses of magnetic field of high rate of rise/fall, so-called gradient fields, which exist only during examination of patients. The level of workers’ exposure depends both on the type of the magnet and on the ergonomical characteristic of design of the particular MRI scanner. This paper presents the current state of the art on occupational exposure to static magnetic field health effects, gaps in scientific data, MRI workers’ exposure characteristics, research needs, and suggestions for the exposure assessment protocol for future investigations.     

Study the effect of static magnetic field on chromosomal aberrations on Vicia faba in area with high natural radioactivity

This investigation was performed to evaluate the influence of the static magnetic field (SMF) on chromosomes in Vicia faba cultivated in soil from high background natural activity. Fourteen soil samples were collected from Ramsar area, in north of Iran, which the annual radiation absorbed dose from background radiation is substantially higher than the 20 mSv/year. The specific activity of the radionuclides of ²³²Th, ²³⁶Ra, and ⁴⁰K was measured using gamma spectrometry. The collected soil samples were then divided into 2 separate groups including HR (high natural radioactivity) and LR (low natural radioactivity). The cultivated Vicia faba in both groups were continuously exposed to SMF of 15 mT for 8 days, each 8 h/day starting from 2nd day. The chromosomal aberrations were counted in both groups with and without SMF from root of samples using chromosomal aberration method. The results showed a significant difference between treated and control plants. Chromosomal aberrations including bridge, fragments, and lagging chromosomes in prophase, metaphase, anaphase, and telophase enhanced significantly in treated groups compared with controls.     

EMF effects on microcirculatory system

Authors review the importance of studying the effects of electromagnetic fields (EMF) on microcirculatory system, especially in respect of possibility that vasculature may have direct and indirect role in interaction of static magnetic fields (SMF). We outline the physiological importance of microcirculation and relatively new methods of evaluation technique in vivo and explain in details the local and/or whole body exposure effects of SMF with␣range of 0.3–180 mT, power frequency EMF with range of 0.1–30 mT and microwaves at 1.5 GHz with range 0.08–8 W/kg brain average specific absorption rate (SAR) on microcirculatory systems in different tissues in experimental animals.     

Immune stimulation in fish and chicken through weak low frequency electromagnetic fields

A hypothesis is proposed how Low Frequency Electromagnetic Field (LF EMF) exposure can stimulate an immune response, based on recent insights in immunology. We hypothesize that the Immunent EMF treatment induces mild stress to cells, which then produce cytokines that function as alarms or so called danger signals for the immune system. In this way EMF treatment takes the place of multiplying pathogens, and the damage these cause, in the triggering of an immune response. In a first series of experiments in␣vitro common carp head kidney-derived phagocytes were used to determine ROS production as a measure for immune activation. Exposure to LF EMF signals (200–5,000 Hz) at 5 μT or 1.5 mT led to 42 or 33% increase in immune activity, respectively, compared to negative control values. EMF could also additionally stimulate chemically pre-stimulated samples up to 18% (5 μT) or 22% (1.5 mT). Significance of increase in ROS production in the total series was: p < 0.0001. In a second series of experiments in␣vitro commercial goldfish were used. Groups of fish were housed under equal conditions in at least four control tanks and 8–16 EMF-exposed tanks. Exposure was done with a predominantly vertical field at field strengths (rms) between 0.15 and 50 μT. Without treatment mortality was about 50% after 18 days, while the treatment at 5 μT reduced it to 20% on average. At field strengths 0.15, 0.5, 1.5, 5, 15 and 50 μT an equally strong effect was found. Reducing the field strength to 0.05, 0.06, 0.01 and 0.003 μT showed a gradually decreasing effect, which only at 0.003 μT is no longer statistically significant. Finally, in␣vitro experiments were done with 560 commercial broiler chickens exposed to infection pressure from coccidiosis. EMF exposure at 6.5 μT reduced intestinal lesions by 40% and improved feed conversion by 8%.     

In Vitro Evaluation of Biological Effects on Human Keratinocytes Exposed to 900 MHz Electromagnetic Field

Summary The biological effects of electromagnetic radiation at ultra high frequency on human keratinocytes were investigated. HaCaT cell system, a spontaneously immortalized human keratinocytes cell line, was chosen as model since skin is usually exposed to electromagnetic radiation at considered frequency more than inner tissues. HaCaT cells were exposed to a pure sinusoidal field at a frequency of 900 MHz (average SAR levels ranging from 0.04 to 0.08 W/kg) in plane wave condition inside a GTEM chamber for time intervals of 18 hours at a controlled temperature of 37^∘C. Growth curves were obtained for exposed and control cells, and a reduction in the number of exposed cells in comparison to unexposed ones was found; however the number of dead cells was not significantly different in exposed and unexposed samples. In order to investigate whether the reduction in cell proliferation of exposed cells was due to the activation of a differentiative process, the expression of two hallmarks of differentiation was examined. Both keratin 1 and involucrin expression was increased in exposed in comparison to unexposed cells. These results suggest that this protocol of exposure to 900 MHz electromagnetic field can trigger a differentiation program in HaCaT cells.     

Static magnetic field action on some markers of inflammation in animal model system—in vivo

Experimentally induced acute inflammation in rats is a good model system which includes the complexity and dynamics of the processes; moreover there are many defined markers for following and estimating changes in an observed system. In this paper, we discuss an in vivo model of acute inflammation induced by carrageenan. Carrageenan-induced paw edema is a model of non-infectious acute inflammatory reaction to assess the contribution of mediators involved in vascular changes associated with acute inflammation and potential treatments. A complex approach into the investigation of possible effects of static magnetic fields (SMF) action on experimentally induced acute inflammation in rats (by measurements of the levels of specific stress markers) is very important in understanding the possible inflammatory mitigation effects, pain relief, and oxidative stress state of an organism. This approach could help for better understanding of the possible mechanisms of interaction of dynamic processes such as inflammation healing and pain relief with external SMF (25 mT at 10, 20 and 30 min exposure time). Results indicate that SMF with B = 25 mT for 30 min diminished the inflammatory process and decreased the levels of inflammatory markers (fibrinogen) and stress markers (ACTH, Cor) into the blood plasma in rats as when compared with sham exposed animals. The exact mechanism by which SMF contributes to the acceleration of inflammatory healing and decrease of inflammation markers in blood plasma in rats still remains unclear. We assume that two possible mechanisms exist. One is the direct interaction of SMF with free active oxygen forms (free radicals) affected by their membrane processes and related with the physiological functions. Another possible mechanism might be related to dynamic regulation of inflammation healing process.     

弱磁场强化零价铁对水中偶氮染料脱色降解的作用初探

本文以橙黄Ⅰ、橙黄Ⅱ、橙黄Ⅳ和日落黄4种偶氮染料为目标染料,首次尝试利用外加弱磁场(~20 mT)的方法来强化零价铁脱色降解偶氮染料。结果表明加磁或不加磁时反应过程均符合一级反应动力学。在磁场的存在下,4种偶氮染料的降解速率都较不加磁场时有很大的提高,提高倍数分别为110.67、111.97、59.51和94.00。弱磁场对零价铁降解偶氮染料的促进作用可能是由于外加磁场所产生的洛伦兹力以及零价铁表面产生的感应磁场所产生的磁场梯度力促进了Fe2+的释放,加快了零价铁的腐蚀,促进零价铁释放更多电子和新生态氢,加速了—N=N—键的断裂,从而强化了染料的脱色降解。     

Influence of DC electric and magnetic fields on silicon solar cells/modules

ABSTRACT

In this study, the impact of DC electric and magnetic fields on the output power, open-circuit voltage, and photocurrent density of a silicon photovoltaic (PV) cell/module is assessed. In this regard, the influence of DC electric and magnetic fields is first evaluated in theory by formulating and discussing related basis and concepts. Then, experimental measurements and data obtained from two different sets of experiments are given that verify theoretical results. In theory and practice, it is shown that depending on the direction of a DC electric field applied to a silicon PV cell/module, it causes an increase or reduction in the output power and open-circuit voltage of the PV cell/module. In detail, when the DC electric field points in the direction of the junction electric field of the PV cell(s), the output power and open-circuit voltage of the silicon PV cell/module increase, otherwise the output power and open-circuit voltage decrease. Regarding the magnetic field, it is proved that depending on the direction of a DC magnetic field applied to a silicon PV cell/module, different effects are observed. In detail, when the DC magnetic field points along the junction electric field of the PV cell(s), it has no effect on the output power and open-circuit voltage of the silicon PV cell/module. But, the output power and open-circuit voltage of the silicon PV cell/module decrease when the DC magnetic field points in the other directions. Moreover, the reduction in the output power and open-circuit voltage reaches its peak when the DC magnetic field is applied in the direction perpendicular to the junction electric field.     

Histochemical and histopathological study of the intestine of the earthworm (Pheretima elongata) exposed to a field dose of the herbicide glyphosate

Histopathological and histochemical variations in non-specific esterases of the intestinal epithelial lining of the earthworm (Pheretima elongata), exposed to a single field dose of the herbicide glyphosate, were studied on the first, second, third, and fourth week of exposure. A severe cell death was observed in the intestine during the first and second weeks of exposure and mortality exceeded 50 percent. In the third week of exposure, the cells of the intestinal lining of the worms which had survived started regenerating and in the fourth week of exposure the epithelial lining regained its original characteristics and architecture, suggesting the high regenerative power of earthworms. Non-specific esterases showed an intense activity in the first week of the exposure and then decreased in the second week to nearly a minimum, where the entire cell structure was lost. However, the activity of the enzyme remained low until the third week where there was a small rise in the activity, and was confined to certain places in the cytoplasm. In the fourth week, almost a complete regeneration of the epithelial lining as well as the non-specific esterases activity was observed and became quite similar to that of the control worms. These results suggest that glyphosate, even at the recommended field dose, could cause cell death and interfere with non-specific esterases activity of the epithelial lining of the intestine of P. elongata causing at least 50 percent mortality in the population of the worms.     

The role of nitrilotriacetate in copper uptake by tobacco

In growth chamber experiments we studied the effect of nitrilotriacetate (NTA) on Cu uptake by tobacco (Nicotiana tabacum L.). Plants were exposed for 6 d to 126 microM Cu and 500 microM NTA in nutrient solutions without and with 10 g L(-1) montmorillonite. Approximately seven times less Cu was dissolved in the montmorillonite solutions than in the nutrient solutions alone. In the absence of NTA, montmorillonite effectively competed with plant roots for Cu, although Cu remained bound to the roots. Nitrilotriacetate increased Cu uptake and translocation into shoots of tobacco by a factor of 3.5 from the nutrient solution and by a factor of 26 from the montmorillonite nutrient solution. Neither growth reduction nor any other visible sign of Cu toxicity was found in the presence of NTA with Cu concentrations of 190 mg kg(-1) in the shoots. In the absence of NTA, high Cu concentrations in root samples led to a brownish discoloration of the roots.     

Biodegradation during contaminant transport in porous media: V. The influence of growth and cell elution on microbial distribution

This study investigated the interaction between microbial growth and cell elution, and their influence on resultant microbial distribution between the aqueous and solid phases during solute transport in a sandy, low-organic-carbon-content porous medium. Miscible displacement experiments were conducted with salicylate as the model compound, and with different initial conditions (e.g., substrate concentrations and cell densities) to attain various degrees of microbial growth. For each experiment, salicylate and dissolved oxygen concentrations as well as cell densities were monitored in the column effluent. Cell densities were also measured in the porous medium at the beginning and end of each experiment. Total microbial growth was determined in two ways, one based on a cell mass balance for the system and the other based on total amount of salicylate degraded. For conditions yielding a considerable amount of microbial growth, the majority of the biomass was associated with the aqueous phase (68-90%). Conversely, under minimal-growth conditions, most cells (approximately 60-70%) were attached to particle surfaces. Significant cell elution was observed for most conditions, the rate of which increased in the presence of the substrate. The results suggest that the increase in aqueous-phase cells observed for the experiments exhibiting the greatest growth is associated with the production of new cells, and that under appropriate conditions aqueous-phase biomass can contribute significantly to contaminant biodegradation.     

Systemic Effect: A New Approach to Magnetic Field Therapy

Summary Despite of decades of successful worldwide use of magnetic/electromagnetic field therapy, the answer to the question of possible mechanisms of action is still lacking. Scientific reports of successful therapeutic use of magnetic/electromagnetic fields are worldwide; however, our understanding of the underlying mechanism is limited. This paper presents a new hypothesis that therapeutic benefit of magnetic fields might result from effects that originated on the level of important systems in human body. It is known now that the life is an electromagnetic event in aqueous medium. Therefore, an appropriate choice of magnetic and/or electromagnetic field may be expected to initiate systemic changes that result in efficacious effects distant from the point of application. Observations of this phenomenon have been reported in at least two forms: (1) neutralization of the pain experience distant to the point of magnetic field exposure; and, (2) various alterations of T-lymphocytes in response to pain and to magnetic fields. Extrapolating these observations to the level of blood-vessel system, one might hypothesize that a “healthy” cell does not respond as readily to the applied fields as do abnormal cells (which are in a disease or injury state).     

Influence of static magnetic fields on nerve regeneration in vitro

Our research involves determining how non-invasive electric and magnetic fields influence neuronal growth in vitro. In previous studies we have shown that pulsed electromagnetic fields (PEMF) as well as direct current (DC) alone stimulate neurite outgrowth from dorsal root ganglion explants [Sisken et al. 1984; Sisken et al. (Restor Neurol Neurosci 1:303–309, 1990); Greenebaum et al. (Bioelectromagnetics 17:293–302, 1996)]. A maximum response was obtained when nerve growth factor (NGF) was also present in the medium. The results of our experiments using static magnetic fields of different strengths are presented below and indicate that fields of high magnetic strength (450–900 gauss) with added NGF stimulate neurite outgrowth comparable to the response obtained with PEMF plus NGF.