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1.
Bioelectromagnetics ; 39(3): 217-230, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29125193

RESUMEN

Exposure to specific electromagnetic field (EMF) patterns can affect a variety of biological systems. We have shown that exposure to Thomas-EMF, a low-intensity, frequency-modulated (25-6 Hz) EMF pattern, inhibited growth and altered cell signaling in malignant cells. Exposure to Thomas-EMF for 1 h/day inhibited the growth of malignant cells including B16-BL6 mouse melanoma cells, MDA-MB-231, MDA-MB-468, BT-20, and MCF-7 human breast cancer and HeLa cervical cancer cells but did not affect non-malignant cells. The Thomas-EMF-dependent changes in cell proliferation were mediated by adenosine 3',5'-cyclic monophosphate (cAMP) and extracellular-signal-regulated kinase (ERK) signaling pathways. Exposure of malignant cells to Thomas-EMF transiently changed the level of cellular cAMP and promoted ERK phosphorylation. Pharmacologic inhibitors (SQ22536) and activators (forskolin) of cAMP production both blocked the ability of Thomas-EMF to inhibit cell proliferation, and an inhibitor of the MAP kinase pathway (PD98059) was able to partially block Thomas-EMF-dependent inhibition of cell proliferation. Genetic modulation of protein kinase A (PKA) in B16-BL6 cells also altered the effect of Thomas-EMF on cell proliferation. Cells transfected with the constitutively active form of PKA (PKA-CA), which interfered with ERK phosphorylation, also interfered with the Thomas-EMF effect on cell proliferation. The non-malignant cells did not show any EMF-dependent changes in cAMP levels, ERK phosphorylation, or cell growth. These data indicate that exposure to the specific Thomas-EMF pattern can inhibit the growth of malignant cells in a manner dependent on contributions from the cAMP and MAP kinase pathways. Bioelectromagnetics. 39;217-230, 2018. © 2017 Wiley Periodicals, Inc.


Asunto(s)
AMP Cíclico/metabolismo , Campos Electromagnéticos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de la radiación , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de la radiación , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Humanos , Ratones , Fosforilación/efectos de la radiación , Factores de Tiempo
2.
Bioelectromagnetics ; 38(3): 165-174, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28026051

RESUMEN

Exposure to low intensity, low frequency electromagnetic fields (EMF) has effects on several biological systems. Spatiotemporal characteristics of these EMFs are critical. The effect of several complex EMF patterns on the proliferation of B16-BL6 mouse melanoma cells was tested. Exposure to one of these patterns, the Thomas-EMF, inhibited cell proliferation and promoted calcium uptake. The Thomas-EMF is coded from a digital-to-analog file comprised of 849 points, which provides power to solenoids and can be set to alter timing, intensity, and duration of variable EMF. Setting the point duration to 3 ms generated a time-varying EMF pattern which began at 25 Hz and slowed to 6 Hz over a 2.5 s repeat. Exposing B16-BL6 cells to Thomas-EMF set to 3 ms for 1 h/day inhibited cell proliferation by 40% after 5 days, while setting the point duration to 1, 2, 4, or 5 ms had no effect on cell proliferation. Similarly, exposing cells to Thomas-EMF set to 3 ms promoted a three-fold increase in calcium uptake after 1 h, while the other timings had no effect. Exposure to Thomas-EMF for as short as 15 min/day slowed cell proliferation, but exposure for 1 h/day was optimal. This corresponded to the effect on calcium uptake where uptake was detected after 15 min exposure and was maximal by 1 h of treatment. Studies show that the specific spatiotemporal character of EMF is critical in mediating their biological activities. Bioelectromagnetics. 38:165-174, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Campos Electromagnéticos , Melanoma Experimental/patología , Animales , Calcio/metabolismo , Línea Celular Tumoral , Proliferación Celular , Magnetoterapia , Melanoma Experimental/metabolismo , Melanoma Experimental/terapia , Ratones , Factores de Tiempo
3.
PLoS One ; 10(4): e0124136, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25875081

RESUMEN

Electromagnetic field (EMF) exposures affect many biological systems. The reproducibility of these effects is related to the intensity, duration, frequency, and pattern of the EMF. We have shown that exposure to a specific time-varying EMF can inhibit the growth of malignant cells. Thomas-EMF is a low-intensity, frequency-modulated (25-6 Hz) EMF pattern. Daily, 1 h, exposures to Thomas-EMF inhibited the growth of malignant cell lines including B16-BL6, MDA-MB-231, MCF-7, and HeLa cells but did not affect the growth of non-malignant cells. Thomas-EMF also inhibited B16-BL6 cell proliferation in vivo. B16-BL6 cells implanted in syngeneic C57b mice and exposed daily to Thomas-EMF produced smaller tumours than in sham-treated controls. In vitro studies showed that exposure of malignant cells to Thomas-EMF for > 15 min promoted Ca(2+) influx which could be blocked by inhibitors of voltage-gated T-type Ca(2+) channels. Blocking Ca(2+) uptake also blocked Thomas-EMF-dependent inhibition of cell proliferation. Exposure to Thomas-EMF delayed cell cycle progression and altered cyclin expression consistent with the decrease in cell proliferation. Non-malignant cells did not show any EMF-dependent changes in Ca(2+) influx or cell growth. These data confirm that exposure to a specific EMF pattern can affect cellular processes and that exposure to Thomas-EMF may provide a potential anti-cancer therapy.


Asunto(s)
Canales de Calcio Tipo T/metabolismo , Campos Electromagnéticos , Animales , Apoptosis , Calcio/metabolismo , Línea Celular Tumoral , Proliferación Celular , Células HeLa , Humanos , Células MCF-7 , Magnetoterapia , Masculino , Melanoma Experimental/patología , Melanoma Experimental/radioterapia , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Factores de Tiempo , Trasplante Homólogo
4.
J Altern Complement Med ; 20(8): 649-53, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24967637

RESUMEN

OBJECTIVES: The study objective was to discern whether the coherence between brain activities of the "patient" and practitioner differ between Reiki experts and novices. RATIONALE: If the physical process associated with Reiki involves "convergence" between the practitioner and subject, then this congruence should be evident in time-dependent shared power within specific and meaningful frequency electroencephalographic bands. DESIGN: Simultaneous quantitative electroencephalogram measures (19 channels) were recorded from 9 pairs of subjects when 1 of the pairs was an experienced Reiki practitioner or had just been shown the procedure. Pairs recorded their experiences and images. SETTING/LOCATION: The "practitioner" and "patient" pairs were measured within a quiet, comfortable acoustic chamber. OUTCOME MEASURES: Real-time correlations and coherence between pairs of brains for power (µV(2)·Hz(-1)) within the various frequency bands over the 10-min sessions were recorded and analyzed for each pair. Descriptors of experiences were analyzed for word meanings. RESULTS: Only the coherence within the theta range increased over time between the brains of the Reiki pairs relative to the Sham pairs, particularly over the left hemisphere. The pleasantness-unpleasantness rating for the words employed to describe experiences written after the experiment were more congruent for the Reiki pairs compared to the reference pairs. CONCLUSIONS: The increased synchronization of the cerebral activity of the participant and the practitioner during proximal therapies involving touch such as Reiki may be an important component of any subsequent beneficial effects.


Asunto(s)
Encéfalo/fisiología , Personal de Salud/psicología , Pacientes/psicología , Tacto Terapéutico/psicología , Ritmo Teta/fisiología , Análisis de Varianza , Electroencefalografía , Femenino , Humanos , Masculino , Adulto Joven
5.
Epilepsy Behav ; 27(1): 220-4, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23348244

RESUMEN

The similarity of the proportions of different types of experiences reported during surgical electrical stimulation of epileptic temporal lobes published in the scientific literature and those reported following exposures to weak, applied magnetic fields was supported by direct comparisons in a retrospective analysis. Of the 20 types of specific experiences, the surgical stimulation groups reported proportionally more fear experiences, while the groups exposed to temporally patterned magnetic fields applied across the temporoparietal regions reported more somesthetic and vestibular experiences. There were no group differences for the other 17 types of experiences. Calculations indicated that the spread of charge displacement from neuronal membranes by the currents employed in the surgical studies and the magnetic field energy associated with the applied fields could affect similar numbers of cortical neurons. The similar subjective experiences of the two techniques indicate that the less invasive procedures might be employed to systematically study complex partial seizures.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Epilepsia del Lóbulo Temporal/terapia , Magnetoterapia/métodos , Lóbulo Temporal/fisiología , Electrodos Implantados , Humanos , Estudios Retrospectivos , Encuestas y Cuestionarios
6.
J Altern Complement Med ; 17(4): 351-5, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21480784

RESUMEN

OBJECTIVES: The study objective was to determine the quantitative electroencephalographic correlates of meditation, as well as the effects of hindering (15 Hz) and facilitative (7 Hz) binaural beats on the meditative process. DESIGN: The study was a mixed design, with experience of the subject as the primary between-subject measure and power of the six classic frequency bands (δ, θ, low α, high α, ß, γ), neocortical lobe (frontal, temporal, parietal, occipital), hemisphere (left, right), and condition (meditation only, meditation with 7-Hz beats, meditation with 15-Hz beats) as the within-subject measures. LOCATION: The study was conducted at Laurentian University in Sudbury, Ontario, Canada. SUBJECTS: The subjects comprised novice (mean of 8 months experience) and experienced (mean of 18 years experience) meditators recruited from local meditation groups. INTERVENTION: Experimental manipulation included application of hindering and facilitative binaural beats to the meditative process. RESULTS: Experienced meditators displayed increased left temporal lobe δ power when the facilitative binaural beats were applied, whereas the effect was not observed for the novice subjects in this condition. When the hindering binaural beats were introduced, the novice subjects consistently displayed more γ power than the experienced subjects over the course of their meditation, relative to baseline. CONCLUSIONS: Based on the results of this study, novice meditators were not able to maintain certain levels of θ power in the occipital regions when hindering binaural beats were presented, whereas when the facilitative binaural beats were presented, the experienced meditators displayed increased θ power in the left temporal lobe. These results suggest that the experienced meditators have developed techniques over the course of their meditation practice to counter hindering environmental stimuli, whereas the novice meditators have not yet developed those techniques.


Asunto(s)
Estimulación Acústica/métodos , Encéfalo/fisiología , Meditación , Psicofisiología , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Meditación/psicología , Ontario
7.
Cogn Process ; 12(2): 141-50, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21350845

RESUMEN

Previous researchers have studied meditation practices as a means to understand consciousness as well as altered states of consciousness. Various meditation techniques, such as Transcendental Meditation (TM) and Qigong, have been explored with source localization tools; however, the concentrative meditation technique has yet to be fully studied in this manner. The current study demonstrates findings, which outline differential activation in a self-referential default network during meditation in participants who espouse themselves as regular concentrative meditation practitioners, as well as comparisons with a control group practicing a modified version of the relaxation response. The results are compared with other putative experimental findings employing other meditation techniques, and the findings outlined in the current study are discussed with respect to changes in perceptual awareness often reported by meditators.


Asunto(s)
Encéfalo/fisiología , Meditación , Adulto , Concienciación/fisiología , Mapeo Encefálico , Electroencefalografía , Femenino , Humanos , Masculino , Relajación/fisiología
8.
J Photochem Photobiol B ; 102(2): 156-60, 2011 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-21146998

RESUMEN

The therapeutic effects elicited by photobiostimulation in the near infrared range may be associated with increased proliferation rate of particular cell-types. The present study utilized commercial light emitting diodes to investigate the effects of low-level near-infrared radiation on the proliferation rate of stem cells in amputated planarian. Whole and amputated animals were exposed to either ambient diurnal lighting, darkness, white light, red light, or near-infrared (880 nm) light. Irradiation was consistent for the duration of the experiments and was provided using commercial 5mm light emitting diodes (∼1.0 mW/m(2) in power density and ∼0.01 J/cm(2) in radiant exposure). Compared to other groups amputated planarian exposed to near-infrared displayed increased mobility by the 3rd day of exposure (F((4,26))=4.31, p<0.04, η(2)=41%). Higher densities of stem cells were measured in these worms 84 h post injury (F((4,72))=4.78, p<0.01, η(2)=21%). These findings suggest that non-coherent light sources with power-densities about 1000 times lower than contemporary low-power laser settings remain effective in generating photobiostimulation effects and warrants further investigation on stem-cell proliferation induced by near-infrared light emitting diodes.


Asunto(s)
Planarias/efectos de la radiación , Células Madre/citología , Animales , Movimiento Celular , Proliferación Celular , Terapia por Luz de Baja Intensidad , Planarias/citología , Factores de Tiempo
9.
Int J Radiat Biol ; 86(2): 79-88, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20148694

RESUMEN

PURPOSE: To measure the effect of exposure to a specific spatial-temporal, hysiologically-patterned electromagnetic field presented using different geometric configurations on the growth of experimental tumours in mice. METHODS: C57b male mice were inoculated subcutaneously with B16-BL6 melanoma cells in two blocks of experiments separated by six months (to control for the effects of geomagnetic field). The mice were exposed to the same time-varying electromagnetic field nightly for 3 h in one of six spatial configurations or two control conditions and tumour growth assessed. RESULTS: Mice exposed to the field that was rotated through the three spatial dimensions and through all three planes every 2 sec did not grow tumours after 38 days. However, the mice in the sham-field and reference controls showed massive tumours after 38 days. Tumour growth was also affected by the intensity of the field, with mice exposed to a weak intensity field (1-5 nT) forming smaller tumours than mice exposed to sham or stronger, high intensity (2-5 microT) fields. Immunochemistry of tumours from those mice exposed to the different intensity fields suggested that alterations in leukocyte infiltration or vascularisation could contribute to the differences in tumour growth. CONCLUSIONS: Exposure to specific spatial-temporal regulated electromagnetic field configurations had potent effects on the growth of experimental tumours in mice.


Asunto(s)
Magnetoterapia , Melanoma Experimental/terapia , Animales , Línea Celular Tumoral , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Masculino , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Neovascularización Patológica
10.
Electromagn Biol Med ; 28(4): 374-82, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20017628

RESUMEN

The proportions of Stage 2 spindles present per second over the prefrontal and temporal lobes of a patient who had been experiencing complex partial epileptic-like experiences and disturbances in sleep patterns for four years following a closed head injury were measured while a weak (1 microT) burst-firing magnetic field was applied transcerebrally through the temporoparietal regions. In several successive segments during the exposure the onsets of the spindles were significantly correlated (rhos between 0.30 and 0.40) with the onset of the field that was presented once every 3 s for about 0.7 s. Lag/lead analyses indicated only the contemporary occurrence of the fields and the spindles were significantly correlated over time. These results suggest that some states of consciousness, particularly those associated with the "epilepsy spectrum disorder" may be more sensitive to entrainment or "synchronization" by weak complex magnetic fields whose temporal structures are designed to simulate natural brain activity.


Asunto(s)
Corteza Cerebral/fisiología , Electroencefalografía , Epilepsia/fisiopatología , Epilepsia/terapia , Magnetoterapia , Magnetismo , Fases del Sueño/fisiología , Corteza Cerebral/fisiopatología , Sincronización Cortical , Epilepsia/etiología , Femenino , Traumatismos Cerrados de la Cabeza/complicaciones , Humanos , Persona de Mediana Edad , Factores de Tiempo
11.
Int J Neurosci ; 119(2): 166-84, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19125372

RESUMEN

To discern if specific structures of the rat brain contained more foci of lymphocytes following induction of experimental allergic encephalomyelitis and exposures to weak, amplitude-modulated magnetic fields for 6 min once per hour during the scotophase, the residuals between the observed and predicted values for the numbers of foci for 320 structures were obtained. Compared to the brains of sham-field exposed rats, the brains of rats exposed to 7-Hz 50 nT (0.5 mG) amplitude-modulated fields showed more foci within hippocampal structures and the dorsal central grey of the midbrain while those exposed to 7-Hz 500 nT (5 mG) fields showed greater densities within the hypothalamus and optic chiasm. The brains of rats exposed to either the 50 nT or 500 nT amplitude-modulated 40-Hz fields displayed greater densities of foci within the midbrain structures related to rapid eye movement. Most of the enhancements of infiltrations within the magnetic field-exposed rats occurred in structures within periventricular or periaqueductal regions and were both frequency- and intensity-dependent. The specificity and complexity of the configurations of the residuals of the numbers of infiltrated foci following exposures to the different fields suggest that the brain itself may be a "sensory organ" for the detection of these stimuli.


Asunto(s)
Encéfalo/efectos de la radiación , Ritmo Circadiano/efectos de la radiación , Campos Electromagnéticos , Encefalomielitis Autoinmune Experimental/fisiopatología , Activación de Linfocitos/efectos de la radiación , Linfocitos/efectos de la radiación , Animales , Encéfalo/anatomía & histología , Encéfalo/inmunología , Ventrículos Cerebrales/fisiología , Quimiotaxis de Leucocito/inmunología , Quimiotaxis de Leucocito/efectos de la radiación , Ritmo Circadiano/inmunología , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Hipocampo/inmunología , Hipocampo/efectos de la radiación , Hipotálamo/inmunología , Hipotálamo/efectos de la radiación , Mesencéfalo/inmunología , Mesencéfalo/efectos de la radiación , Quiasma Óptico/inmunología , Quiasma Óptico/efectos de la radiación , Ratas , Ratas Endogámicas Lew , Sueño REM/inmunología , Sueño REM/efectos de la radiación
12.
Med Hypotheses ; 66(4): 811-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16321472

RESUMEN

A biophysical hypothesis to explain the powerful ameliorating effects of weak (nanoTesla range) magnetic fields on melatonin-related diseases is presented. The effects are dependent upon the molarity of the melatonin within specific organ spaces. The optimal ameliorating effects upon experimental allergic encephalomyelitis for both the derived intensities (about 35 and 70 nT) and the frequency (7 Hz) were congruent with the empirical observations from previously published and unpublished experiments with rats involving about 1-5000 nT strengths of either 0.5, 7, 40, or 60 Hz magnetic fields. The hypothesis predicts that weaker magnetic fields within the nanoTesla to picoTesla range would optimally affect concentrations of melatonin (in this situation) within the micromolar range and that neurological states (epilepsy) or conditions (ethanol, antidepressants, sleep deprivation) that affect nocturnal melatonin levels in human beings would determine the optimal effective intensity within the 7 Hz range. The resonance solution also suggests that mitochondrial proton gradients may be critical to the process. The model offers an alternative explanation to the variations of Faraday's Law and the Boltzmann constant that have been employed to explain and to dismiss biological effects from weak magnetic fields.


Asunto(s)
Magnetismo/uso terapéutico , Melatonina/metabolismo , Esclerosis Múltiple/terapia , Animales , Humanos , Ratas
13.
Phytother Res ; 18(9): 700-5, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15478209

RESUMEN

About 1 week after the induction of status epilepticus in male rats by a single systemic injection of lithium (3 mEq/kg) and pilocarpine (30 g/kg), rats were continuously administered one of three herbal treatments through the water supply for 30 days. A fourth group received colloidal minerals and diluted food grade hydrogen peroxide in tap water, while a fifth group of rats received only tap water (control). Herbal treatments were selected for their historical antiseizure activities and sedative actions on the nervous system. The numbers of spontaneous seizures per day during a 15 min observation interval were recorded for each rat during the treatment period and during an additional 30 days when only tap water was given. Rats that received a weak solution of the three herbal fluid extracts of Scutellaria lateri flora (Skullcap), Gelsemium sempervirens (Gelsemium) and Datura stramonium (Jimson Weed) displayed no seizures during treatment while all the other groups were not seizure-free. However, when this treatment was removed, the rats in this group displayed numbers of spontaneous seizures comparable to the controls. Although there is no proof that herbal remedies can control limbic or temporal lobe epilepsy, the results of this experiment strongly suggest that the appropriate combination of herbal compounds may be helpful as adjunctive interventions.


Asunto(s)
Anticonvulsivantes/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales , Convulsiones/prevención & control , Administración Oral , Animales , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/uso terapéutico , Datura stramonium , Gelsemium , Litio , Pilocarpina , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Distribución Aleatoria , Ratas , Ratas Wistar , Scutellaria , Convulsiones/inducido químicamente
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