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1.
Osteoarthritis (OA) is a chronic degenerative condition involving the joints caused by metabolic changes in chondrocytes metabolism. Treatment with magnetic fields (EMFs) produces benefits to patients affected by this pathology. The present research has the aim to investigate, by a proteomic approach, the effect of magnetic fields on cultured chondrocytes, because EMFs interferes greatly with OA chondrocytes metabolism. Human osteoarthritic chondrocytes were obtained from the femur head of osteoarthritis adult patients and were cultured under standard conditions and exposed for precise times both to extremely low-frequency (ELF; 100-Hz) electromagnetic fields and to the Therapeutic Application of Musically Modulated Electromagnetic Fields (TAMMEF), which are characterized by variable frequencies, intensities, and wave shapes. We tested the effects of the different exposure by 2-DE analysis and demonstrated that chondrocytes metabolism was highly influenced by the treatment with EMFs; in fact many proteins change their expression after the stimulation, but differently, depending on whether we use ELF or TAMMEF system.  相似文献   

2.
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).  相似文献   

3.
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however, when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal. Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally, this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction.  相似文献   

4.
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for tissue repair are subjects of this review.  相似文献   

5.
During the last three decades the interest toward clinical application of magnetic and electromagnetic stimulation increased worldwide. Numerous publications have discussed the possibility of exogenous magnetic fields to initiate beneficial effects on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields are increasingly utilized for the treatment of numerous musculoskeletal injuries and pathologies. For example, selected magnetic fields were reported to be beneficial in the treatment of musculoskeletal injuries and post-surgical, post traumatic and chronic wounds, reduction of edema, in the acceleration of pain and stress relief, and thus contribute to healing processes. The application of this modality could be facilitated by establishing the exact dosimetry of application and by searching for biophysical mechanisms of action, as well. It should be remembered that “not all magnets are equal”, therefore the specific medical problem requires a proper diagnostics, a selection of the magnetic field to be applied and a design of the appropriate protocol for treatment. The paper advised that every study and report should carefully explain both the medical problem and the parameters of the applied magnetic field and cautions against generalized statements like “Magnetic field does/does not cause biological response”.  相似文献   

6.
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.  相似文献   

7.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli. Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most) sensitive indicators to detect and quantify physiological effects of electromagnetic fields.  相似文献   

8.
In our paper we studied the effects of exposure to ELF (extremely low frequency) or musically generated TAMMEF (therapeutic application of musically modulated electromagnetic fields) electromagnetic fields on the tumor necrosis factor alpha (TNF-α) release induced by a lipopolysaccharide (LPS) from cultured human lymphomonocytes of peripheral blood. Lymphomonocytes, isolated from blood donors buffy-coat, were prepared using standard techniques in cell culture flasks, kept in CO2 incubator, with controlled temperature and humidity for 5 days. Flasks were subjected to an ELF electromagnetic field (100 Hz sinusoidal) or to TAMMEF electromagnetic fields (with intensity, frequency, and wave shape randomly modified in time, so that all possible codes can occur during a single application). The TNF-α release was determined by ELISA test every 24 h for 92 h and the results were evaluated by a non-parametric test. LPS induces a stronger TNF-α release in cultures that were subjected to ELF when compared with cultures subjected to TAMMEF, at each time period of the experimental protocol. These results seem to indicate that TAMMEF is able to induce a complex modulation of LPS-induced TNF-α release, a cytokine with pro inflammatory property whose release during chronic or neoplastic inflammatory diseases has strong negative effects on several organ systems.  相似文献   

9.
There are many data about the extremely low-frequency electromagnetic fields (ELF-EMF) therapeutic use, especially in the field of oncology. Recent data suggest that 4 Hz EMF having dehydration effect on tissues has a pronounced antitumor activity on sarcoma-180 in mice. It was shown that 4 Hz EMF have pronounced effects on physicochemical properties of water and water solution. Therefore, the aim of the present work was the comparative study of the modulation effect of ELF-EMF on cisplatin-induced changes cell hydration and number of ouabain receptors in membrane of sarcoma-180 tumor tissues. Tissue hydration was measured as wet weight/dry weight and expressed as a water content of g/g in dry weight. The number of 3H-ouabain receptors in membrane was counted by isotope scintillation counter. In conclusion, ELF-EMF can be a possible tool for stimulation of cisPt antitumor effect.  相似文献   

10.
Summary Biological effects of extremely low-frequency electromagnetic fields (ELF-EMF) on microcirculation were investigated in vivo by monitoring arteriole diameters in conscious mice. Measurements of blood vessel diameter were monitored 33 min non-stop before during and after exposure with ELF-EMF and every 389 ms blood vessel diameter were calculated. Using a dorsal skinfold chamber (DSC), and following caudal vein injection of FITC-dextran 250 kDa, the microvasculature (initial arteriole diameter of 45–80 μm), was examined by intravital microscopy and video images were recorded for a total time of 33 min. Arteriole diameter was continuously measured by on-line analysis using a High-speed Digital Machine Vision System CV-2100, using an edge-gap detection algorithm. Since vessel diameters exhibit rhythmic variation expressed by vasomotion, for estimation of microcirculatory activity we used both raw data for frequency analysis of vasomotion (measured frequencies of vasomotion were in the range 0.008÷0.1 Hz) and evaluate mean blood vessel diameter for each 1 min period of time, and make a comparison between Pre, Exposure/Sham exposure and Post exposure periods, with the aim to evaluate possible changes in mean blood vessel diameter as a result of ELF-EMF action. During EMF exposure and post-exposure periods, arteriole diameters increased significantly compared with the pre-exposure period, and the changes were larger during post-exposure. In contrast to sham exposure, vasodilatation of the microvasculature was significantly greater during exposure and post-exposure to 16 Hz EMF. These findings suggest that ELF-EMF may have potential therapeutic use benefit for treating vascular disorders.  相似文献   

11.
Hodgkin–Huxley model, describing generation of action potentials in axons’ membranes, has been used for appreciation of the possible mechanisms of electromagnetic fields influence on neurons’ electrical activity. It follows from the carried calculations that flowing through an axon of the external current pulses, which have an area of rise, an area of DC, and an area of drop, does not influence own excitation pulses passage if periods of rise and drop are slope enough. Depending on the external current parameters, own excitation pulses may not be influenced or may be suppressed at greater velocity of rise and drop of an external current. Moreover, induced excitation pulses appear at definite parameters of an external current. In the case, when at passage through an axon of an external current, own excitation pulses follow one by one (paired pulse facilitation), and the second pulse may be suppressed if its level will not be increased additionally in comparison with the case of an external current absence. It is possible that such increase happens “automatically” as a result of “tuning” (adaptation) of axons to the conditions of flowing through them of an external current. It may be an explanation of the phenomena observed in experiments.  相似文献   

12.
The importance of the assessment of the electromagnetic fields /EMF/ background as a health risk factor for the physiotherapy personnel is discussed in this paper. Wide frequency and amplitude ranges as well as large variety of design prescribed in the rehabilitation program form complicated work conditions. In this paper, we attempt to present and classify this specific work environment, i.e., low intensive EMF background with non homogenous frequency and modulation characteristics, stochastic changes running during day, ground or even underground units’ placement and professional specifics, i.e., chronic EMF expositions, personnel’s trunk and hands exposure, dose-measurement absence, lack of program for prevention and prophylaxis for the assessment of the relatively insufficiently elucidated potential of EMF as a harmful factor for medical staff. Our “Study of the biological effects of the EMF among medical staff from PRM wards—potential of risk reduction”/initialized in 1999/and the original survey card structure are presented in general here first. It has been shown the importance to extend the “native” studies among homogenous professional groups, two of them presented there, as well as the study of the biological effects of EMF in their different aspects, especially taking into account the elevated levels of ionizing and non-ionizing radiation in the environment. This includes the special attention on the exposure of medical staff from PRM units and creation of adequate methods for prevention of unnecessary exposure to these physical factors.  相似文献   

13.
The purpose of this study was to explore the ability of place attachment to predict place-specific and general pro-environment behavioural intentions. The study sample (n = 355) consisted of visitors to a Canadian national park, Point Pelee National Park. The place attachment scale utilized in this study was designed to measure three subdimensions: place identity, place dependence, and place affect. Exploratory factor analysis of data measured by these scales revealed two place attachment subdimensions. Place affect, an individual’s emotions and feelings for a place, acted as a more generalized or pervasive phenomenon. Place affect items loaded on both the place identity (an individual’s cognitive assessment of a place) and place dependence (an individual’s functional assessment of a place). Structural equation modeling confirmed the strength of place attachment’s ability to predict place-related pro-environment intentions. It also identified place attachment’s prediction of pro-environment behavioural intensions related to everyday life. Place identity mediated the effects of place dependence in predicting pro-environment intentions. Further research which utilizes in-depth and longitudinal case studies is suggested to explore the role of place-specific emotion and feelings, as well as place identity in fostering environmentally-responsible action as these factors are theorized to play an important role in promoting pro-environmental behaviour. Studies of place attachment to everyday settings rather than iconic national parks are also called for.  相似文献   

14.
生态示范区建设是实施可持续发展战略的基本经济社会形式。本文简单介绍了彭州市的概况,根据建设的指导思想、建设目标,对彭州市进行生态经济分区,并确定了分区规划目标,相应的提出了重点建设领域,为当地开展生态示范区建设工作提供了理论参考。  相似文献   

15.
We studied the changes in wetland habitats and waterbird communities between the 1980s and the 2000s at Chongming Dongtan, a Ramsar site in the Yangtze River estuary, an ecologically important region. This region is an important stopover site for shorebirds along the East Asian–Australasian flyway and is extensively used by waterfowl. A net loss of 11% of the wetland area was estimated during study periods at Chongming Dongtan. The change was dependent on wetland types: while the area of artificial habitats such as paddy fields and aquacultural ponds more than doubled, more than 65% of natural habitats including sea bulrush (Scirpus mariqueter) and common reed (Phragmites australis) marshes were lost over the two decades. An exotic plant species introduced from North America, smooth cordgrass (Spartina alterniflora), occupied 30% of the vegetated intertidal zone by the 2000s. Although waterbird species richness did not change between the 1980s (110) and the 2000s (111), 13 species found in 1980s were replaced by 14 newly recorded species. Moreover, there were more species with declining trends (58) than with increasing trends (19). The population trends of species were affected by residential status and habitat types. Transients, wintering migrants, and habitat specialists were more likely to show declining trends compared to those breeding at Dongtan (including year-round and summer residents) and habitat generalists. Furthermore, species associated mainly with natural wetlands were more likely to decline than those associated mainly with artificial wetlands. These patterns suggest that the loss and change of wetland habitats at Chongming Dongtan adversely affected local population dynamics and might have contributed to the global decline of some waterbird species. Because Chongming Dongtan provides stopover and wintering habitats for many migratory waterbirds, protection and restoration of natural wetlands at Chongming Dongtan are urgently needed.  相似文献   

16.
Epidemiological studies suggesting the possibility of harmful effects on human (specifically children’s leukaemia) due to long-term exposure to magnetic fields of extremely low frequency (e.g. 50/60 Hz) and relatively low values (i.e. over the microtesla range) have stirred high activity in the topic of magnetic field mitigation. To reduce these fields, it is common to use passive metal screens (e.g. plates made of aluminium or steel). To design them, effective and fast numerical computations are highly desirable. In this article, a method is presented, which computes various parameters of screens in a given shielding problem and yields magnetic field distribution and shielding factors. The method takes into consideration the 3D field distribution and is able to solve systems with large aspect ratios (thin thickness in comparison with its other dimensions); this is a common problem where other methods such as finite elements often experience difficulties. The presented method computes separately the field inside and outside the screens. Afterwards, the solutions are “stitched” together along the border of the subregions. Two practical examples are given of the developed numerical method.  相似文献   

17.
Electromagnetic fields exposure assessment methodology is briefly presented. The basic problems defined for the practical use of electromagnetic fields measurements and numerical calculations carried out for workers exposure assessment in real occupational situations are discussed. The examples of data from real workplace are presented, focusing: spatial distribution of electromagnetic fields affecting worker’s body, complex characteristics of the frequency content, workers activities/moving in the workplace, field impedance, etc. The situation when the use of calculations is required is discussed. The basic requirements for workers exposure assessment protocols are presented. The possible range of the use of internal and external measures of exposure level is also discussed.  相似文献   

18.
In 1988 I published a paper “Electromagnetic fields—a new ecological factor” (Markov 1988). There was no internet and very few cell phones were available. It was not even fear from the hazard of the power lines. However, I want to cite the beginning of this paper: “The contemporary conditions of life put man in dependence of the complex of physical influences on the environment and in the first place—of the electromagnetic fields. The rapid development of science and technology has resulted in the introduction of many new devices and technologies in industry, agriculture, and everyday life. On the other hand, during their phylogenetic and ontogenic development, the living organisms are continuously exposed to the influence of different biotic and abiotic factors. The physical factors are included in the first group, and the entire evolution of life is connected with an adaptation to the action of these factors.” Could I repeat this statement nearly a quarter of century later? Sure, I will. The only difference would be that I will speak not only for electromagnetic fields, but for green-house effects, global warming, volcano eruption, and radiation disasters. I would also discuss the noise and vibration to which people are exposed from early days to the very end of their life traveling with private vehicles or public transport.  相似文献   

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