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1.
Int J Radiat Biol ; 88(3): 245-52, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22124250

RESUMEN

PURPOSE: To investigate whether mobile phone radiation might affect snail nociception, employing radiofrequency (RF) electromagnetic fields (EMF) which, to our knowledge, have hitherto not been studied in a snail model. Exposure to extremely low frequency (ELF) magnetic fields has however been shown to significantly affect nociceptive responses. MATERIALS AND METHODS: In the present study, we exposed 29 land snails of the strain Helix pomatia to global system for mobile communications (GSM) EMF at 1900 MHz at the non-thermal level 48 mW/kg for 1 hour each and 29 snails were sham controls. The experiments took place during the onset of summer, with all snails being well out of hibernation. Before and after GSM or sham exposure, the snails were subjected to thermal pain by being placed on a hot plate. The reaction time for retraction from the hot plate was measured by two blinded observers. RESULTS: Comparing the reaction pattern of each snail before and after exposure, the GSM-exposed snails were less sensitive to thermal pain as compared to the sham controls, indicating that RF exposure induces a significant analgesia (Mann-Whitney p < 0.001). CONCLUSION: This study might support earlier findings, describing beneficial effects of EMF exposure upon nociception.


Asunto(s)
Campos Electromagnéticos , Caracoles Helix , Nocicepción/efectos de la radiación , Terapia por Radiofrecuencia , Animales , Teléfono Celular
2.
Environ Health Perspect ; 118(3): 394-9, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20064781

RESUMEN

BACKGROUND: It is widely accepted that DNA double-strand breaks (DSBs) and their misrepair in stem cells are critical events in the multistage origination of various leukemias and tumors, including gliomas. OBJECTIVES: We studied whether microwaves from mobile telephones of the Global System for Mobile Communication (GSM) and the Universal Global Telecommunications System (UMTS) induce DSBs or affect DSB repair in stem cells. METHODS: We analyzed tumor suppressor TP53 binding protein 1 (53BP1) foci that are typically formed at the sites of DSB location (referred to as DNA repair foci) by laser confocal microscopy. RESULTS: Microwaves from mobile phones inhibited formation of 53BP1 foci in human primary fibroblasts and mesenchymal stem cells. These data parallel our previous findings for human lymphocytes. Importantly, the same GSM carrier frequency (915 MHz) and UMTS frequency band (1947.4 MHz) were effective for all cell types. Exposure at 905 MHz did not inhibit 53BP1 foci in differentiated cells, either fibroblasts or lymphocytes, whereas some effects were seen in stem cells at 905 MHz. Contrary to fibroblasts, stem cells did not adapt to chronic exposure during 2 weeks. CONCLUSIONS: The strongest microwave effects were always observed in stem cells. This result may suggest both significant misbalance in DSB repair and severe stress response. Our findings that stem cells are most sensitive to microwave exposure and react to more frequencies than do differentiated cells may be important for cancer risk assessment and indicate that stem cells are the most relevant cellular model for validating safe mobile communication signals.


Asunto(s)
Teléfono Celular , Fibroblastos/efectos de la radiación , Péptidos y Proteínas de Señalización Intracelular/efectos de la radiación , Microondas/efectos adversos , Células Madre/efectos de la radiación , Roturas del ADN de Doble Cadena , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células Madre/citología , Células Madre/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53
3.
Pathophysiology ; 16(2-3): 103-12, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19345073

RESUMEN

Microwaves were for the first time produced by humans in 1886 when radio waves were broadcasted and received. Until then microwaves had only existed as a part of the cosmic background radiation since the birth of universe. By the following utilization of microwaves in telegraph communication, radars, television and above all, in the modern mobile phone technology, mankind is today exposed to microwaves at a level up to 10(20) times the original background radiation since the birth of universe. Our group has earlier shown that the electromagnetic radiation emitted by mobile phones alters the permeability of the blood-brain barrier (BBB), resulting in albumin extravasation immediately and 14 days after 2h of exposure. In the background section of this report, we present a thorough review of the literature on the demonstrated effects (or lack of effects) of microwave exposure upon the BBB. Furthermore, we have continued our own studies by investigating the effects of GSM mobile phone radiation upon the blood-brain barrier permeability of rats 7 days after one occasion of 2h of exposure. Forty-eight rats were exposed in TEM-cells for 2h at non-thermal specific absorption rates (SARs) of 0mW/kg, 0.12mW/kg, 1.2mW/kg, 12mW/kg and 120mW/kg. Albumin extravasation over the BBB, neuronal albumin uptake and neuronal damage were assessed. Albumin extravasation was enhanced in the mobile phone exposed rats as compared to sham controls after this 7-day recovery period (Fisher's exact probability test, p=0.04 and Kruskal-Wallis, p=0.012), at the SAR-value of 12mW/kg (Mann-Whitney, p=0.007) and with a trend of increased albumin extravasation also at the SAR-values of 0.12mW/kg and 120mW/kg. There was a low, but significant correlation between the exposure level (SAR-value) and occurrence of focal albumin extravasation (r(s)=0.33; p=0.04). The present findings are in agreement with our earlier studies where we have seen increased BBB permeability immediately and 14 days after exposure. We here discuss the present findings as well as the previous results of altered BBB permeability from our and other laboratories.

4.
Bioelectromagnetics ; 30(2): 129-41, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18839414

RESUMEN

We have recently described frequency-dependent effects of mobile phone microwaves (MWs) of global system for mobile communication (GSM) on human lymphocytes from persons reporting hypersensitivity to electromagnetic fields and healthy persons. Contrary to GSM, universal global telecommunications system (UMTS) mobile phones emit wide-band MW signals. Hypothetically, UMTS MWs may result in higher biological effects compared to GSM signal because of eventual "effective" frequencies within the wideband. Here, we report for the first time that UMTS MWs affect chromatin and inhibit formation of DNA double-strand breaks co-localizing 53BP1/gamma-H2AX DNA repair foci in human lymphocytes from hypersensitive and healthy persons and confirm that effects of GSM MWs depend on carrier frequency. Remarkably, the effects of MWs on 53BP1/gamma-H2AX foci persisted up to 72 h following exposure of cells, even longer than the stress response following heat shock. The data are in line with the hypothesis that the type of signal, UMTS MWs, may have higher biological efficiency and possibly larger health risk effects compared to GSM radiation emissions. No significant differences in effects between groups of healthy and hypersensitive subjects were observed, except for the effects of UMTS MWs and GSM-915 MHz MWs on the formation of the DNA repair foci, which were different for hypersensitive (P < 0.02[53BP1]//0.01[gamma-H2AX]) but not for control subjects (P > 0.05). The non-parametric statistics used here did not indicate specificity of the differences revealed between the effects of GSM and UMTS MWs on cells from hypersensitive subjects and more data are needed to study the nature of these differences.


Asunto(s)
Teléfono Celular , Reparación del ADN , Histonas/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Linfocitos/efectos de la radiación , Microondas , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteína 1 de Unión al Supresor Tumoral P53
5.
Brain Res Bull ; 77(5): 257-63, 2008 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-18782606

RESUMEN

In order to mimic the real life situation, with often life-long exposure to the electromagnetic fields emitted by mobile phones, we have investigated in a rat model the effects of repeated exposures under a long period to Global System for Mobile Communication-900 MHz (GSM-900) radiation. Out of a total of 56 rats, 32 were exposed once weekly in a 2-h period, for totally 55 weeks, at different average whole-body specific absorption rates (SAR) (of in average 0.6 and 60 mW/kg at the initiation of the experimental period). The animals were exposed in a transverse electromagnetic transmission line chamber (TEM-cell) to radiation emitted by a GSM-900 test phone. Sixteen animals were sham exposed and eight animals were cage controls, which never left the animal house. After behavioural tests, 5-7 weeks after the last exposure, the brains were evaluated for histopathological alterations such as albumin extravasation, dark neurons, lipofuscin aggregation and signs of cytoskeletal and neuritic neuronal changes of the type seen in human ageing. In this study, no significant alteration of any these histopathological parameters was found, when comparing the GSM exposed animals to the sham exposed controls.


Asunto(s)
Encéfalo , Teléfono Celular , Campos Electromagnéticos/efectos adversos , Envejecimiento/efectos de la radiación , Animales , Conducta Animal/efectos de la radiación , Barrera Hematoencefálica/efectos de la radiación , Encéfalo/patología , Encéfalo/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Neuronas/citología , Neuronas/efectos de la radiación , Ratas , Ratas Endogámicas F344 , Irradiación Corporal Total
6.
Electromagn Biol Med ; 27(3): 215-29, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18821198

RESUMEN

We investigated the effects of global system for mobile communication (GSM) microwave exposure on the permeability of the blood-brain barrier and signs of neuronal damage in rats using a real GSM programmable mobile phone in the 900 MHz band. Ninety-six non-anaesthetized rats were either exposed to microwaves or sham exposed in TEM-cells for 2 h at specific absorption rates of average whole-body Specific Absorption Rates (SAR) of 0.12, 1.2, 12, or 120 mW/kg. The rats were sacrificed after a recovery time of either 14 or 28 d, following exposure and the extravazation of albumin, its uptake into neurons, and occurrence of damaged neurons was assessed. Albumin extravazation and also its uptake into neurons was seen to be enhanced after 14 d (Kruskal Wallis test: p = 0.02 and 0.002, respectively), but not after a 28 d recovery period. The occurrence of dark neurons in the rat brains, on the other hand, was enhanced later, after 28 d (p = 0.02). Furthermore, in the 28-d brain samples, neuronal albumin uptake was significantly correlated to occurrence of damaged neurons (Spearman r = 0.41; p < 0.01).


Asunto(s)
Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de la radiación , Teléfono Celular , Microondas/efectos adversos , Neuronas/patología , Neuronas/efectos de la radiación , Absorción , Albúminas/metabolismo , Animales , Femenino , Hipocampo/citología , Hipocampo/metabolismo , Hipocampo/efectos de la radiación , Masculino , Neuronas/metabolismo , Permeabilidad/efectos de la radiación , Ratas , Factores de Tiempo
7.
Electromagn Biol Med ; 27(2): 103-26, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18568929

RESUMEN

During the last century, mankind has introduced electricity and during the very last decades, the microwaves of the modern communication society have spread a totally new entity--the radiofrequency fields--around the world. How does this affect biology on Earth? The mammalian brain is protected by the blood-brain barrier, which prevents harmful substances from reaching the brain tissue. There is evidence that exposure to electromagnetic fields at non thermal levels disrupts this barrier. In this review, the scientific findings in this field are presented. The result is a complex picture, where some studies show effects on the blood-brain barrier, whereas others do not. Possible mechanisms for the interactions between electromagnetic fields and the living organisms are discussed. Demonstrated effects on the blood-brain barrier, as well as a series of other effects upon biology, have caused societal anxiety. Continued research is needed to come to an understanding of how these possible effects can be neutralized, or at least reduced. Furthermore, it should be kept in mind that proven effects on biology also should have positive potentials, e.g., for medical use.


Asunto(s)
Barrera Hematoencefálica/fisiología , Barrera Hematoencefálica/efectos de la radiación , Permeabilidad Capilar/fisiología , Permeabilidad Capilar/efectos de la radiación , Electricidad , Ondas de Radio , Animales , Campos Electromagnéticos , Humanos , Modelos Cardiovasculares
8.
Bioelectromagnetics ; 29(3): 219-32, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18044737

RESUMEN

Considering the frequent use of mobile phones, we have directed attention to possible implications on cognitive functions. In this study we investigated in a rat model the long-term effects of protracted exposure to Global System for Mobile Communication-900 MHz (GSM-900) radiation. Out of a total of 56 rats, 32 were exposed for 2 h each week for 55 weeks to radio-frequency electromagnetic radiation at different SAR levels (0.6 and 60 mW/kg at the initiation of the experimental period) emitted by a (GSM-900) test phone. Sixteen animals were sham exposed and eight animals were cage controls, which never left the animal house. After this protracted exposure, GSM-900 exposed rats were compared to sham exposed controls. Effects on exploratory behaviour were evaluated in the open-field test, in which no difference was seen. Effects on cognitive functions were evaluated in the episodic-like memory test. In our study, GSM exposed rats had impaired memory for objects and their temporal order of presentation, compared to sham exposed controls (P = 0.02). Detecting the place in which an object was presented was not affected by GSM exposure. Our results suggest significantly reduced memory functions in rats after GSM microwave exposure (P = 0.02).


Asunto(s)
Teléfono Celular , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Cognición/efectos de la radiación , Memoria/efectos de la radiación , Microondas , Irradiación Corporal Total/métodos , Animales , Femenino , Masculino , Ratas
9.
Bioelectromagnetics ; 27(4): 295-306, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16511873

RESUMEN

We investigated whether exposure of rat brain to microwaves (MWs) of global system for mobile communication (GSM) induces DNA breaks, changes in chromatin conformation and in gene expression. An exposure installation was used based on a test mobile phone employing a GSM signal at 915 MHz, all standard modulations included, output power level in pulses 2 W, specific absorption rate (SAR) 0.4 mW/g. Rats were exposed or sham exposed to MWs during 2 h. After exposure, cell suspensions were prepared from brain samples, as well as from spleen and thymus. For analysis of gene expression patterns, total RNA was extracted from cerebellum. Changes in chromatin conformation, which are indicative of stress response and genotoxic effects, were measured by the method of anomalous viscosity time dependencies (AVTD). DNA double strand breaks (DSBs) were analyzed by pulsed-field gel electrophoresis (PFGE). Effects of MW exposure were observed on neither conformation of chromatin nor DNA DSBs. Gene expression profiles were obtained by Affymetrix U34 GeneChips representing 8800 rat genes and analyzed with the Affymetrix Microarray Suite (MAS) 5.0 software. In cerebellum from all exposed animals, 11 genes were upregulated in a range of 1.34-2.74 fold and one gene was downregulated 0.48-fold (P < .0025). The induced genes encode proteins with diverse functions including neurotransmitter regulation, blood-brain barrier (BBB), and melatonin production. The data shows that GSM MWs at 915 MHz did not induce PFGE-detectable DNA double stranded breaks or changes in chromatin conformation, but affected expression of genes in rat brain cells.


Asunto(s)
Encéfalo/efectos de la radiación , Cromatina/efectos de la radiación , Daño del ADN , ADN/efectos de la radiación , Expresión Génica/efectos de la radiación , Microondas , Animales , Western Blotting , Cromatina/química , Electroforesis en Gel de Campo Pulsado , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Endogámicas F344
10.
Environ Health Perspect ; 113(9): 1172-7, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16140623

RESUMEN

The data on biologic effects of nonthermal microwaves (MWs) from mobile telephones are diverse, and these effects are presently ignored by safety standards of the International Commission for Non-Ionizing Radiation Protection (ICNIRP). In the present study, we investigated effects of MWs of Global System for Mobile Communication (GSM) at different carrier frequencies on human lymphocytes from healthy persons and from persons reporting hypersensitivity to electromagnetic fields (EMFs). We measured the changes in chromatin conformation, which are indicative of stress response and genotoxic effects, by the method of anomalous viscosity time dependence, and we analyzed tumor suppressor p53-binding protein 1 (53BP1) and phosphorylated histone H2AX (gamma-H2AX), which have been shown to colocalize in distinct foci with DNA double-strand breaks (DSBs), using immunofluorescence confocal laser microscopy. We found that MWs from GSM mobile telephones affect chromatin conformation and 53BP1/gamma-H2AX foci similar to heat shock. For the first time, we report here that effects of MWs from mobile telephones on human lymphocytes are dependent on carrier frequency. On average, the same response was observed in lymphocytes from hypersensitive and healthy subjects.


Asunto(s)
Cromatina/efectos de la radiación , Histonas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Linfocitos/efectos de la radiación , Microondas/efectos adversos , Fosfoproteínas/metabolismo , Adulto , Teléfono Celular , Células Cultivadas , Campos Electromagnéticos , Humanos , Hipersensibilidad , Linfocitos/patología , Masculino , Persona de Mediana Edad , Proteína 1 de Unión al Supresor Tumoral P53
11.
Bioelectromagnetics ; 26(3): 173-84, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15768430

RESUMEN

We used exposure to microwaves from a global system for mobile communication (GSM) mobile phone (915 MHz, specific absorption rate (SAR) 37 mW/kg) and power frequency magnetic field (50 Hz, 15 muT peak value) to investigate the response of lymphocytes from healthy subjects and from persons reporting hypersensitivity to electromagnetic field (EMF). The hypersensitive and healthy donors were matched by gender and age and the data were analyzed blind to treatment condition. The changes in chromatin conformation were measured with the method of anomalous viscosity time dependencies (AVTD). 53BP1 protein, which has been shown to colocalize in foci with DNA double strand breaks (DSBs), was analyzed by immunostaining in situ. Exposure at room temperature to either 915 MHz or 50 Hz resulted in significant condensation of chromatin, shown as AVTD changes, which was similar to the effect of heat shock at 41 degrees C. No significant differences in responses between normal and hypersensitive subjects were detected. Neither 915 MHz nor 50 Hz exposure induced 53BP1 foci. On the contrary, a distinct decrease in background level of 53BP1 signaling was observed upon these exposures as well as after heat shock treatments. This decrease correlated with the AVTD data and may indicate decrease in accessibility of 53BP1 to antibodies because of stress-induced chromatin condensation. Apoptosis was determined by morphological changes and by apoptotic fragmentation of DNA as analyzed by pulsed-field gel electrophoresis (PFGE). No apoptosis was induced by exposure to 50 Hz and 915 MHz microwaves. In conclusion, 50 Hz magnetic field and 915 MHz microwaves under specified conditions of exposure induced comparable responses in lymphocytes from healthy and hypersensitive donors that were similar but not identical to stress response induced by heat shock.


Asunto(s)
Daño del ADN , Campos Electromagnéticos , Hipersensibilidad/sangre , Hipersensibilidad/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Linfocitos/metabolismo , Linfocitos/efectos de la radiación , Microondas , Fosfoproteínas/metabolismo , Adulto , Apoptosis/efectos de la radiación , Teléfono Celular , Células Cultivadas , Cromatina/efectos de la radiación , Respuesta al Choque Térmico/efectos de la radiación , Humanos , Hipersensibilidad/patología , Técnicas In Vitro , Linfocitos/patología , Masculino , Persona de Mediana Edad , Conformación de Ácido Nucleico/efectos de la radiación , Método Simple Ciego , Proteína 1 de Unión al Supresor Tumoral P53
12.
Environ Health Perspect ; 111(7): 881-3; discussion A408, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12782486

RESUMEN

The possible risks of radio-frequency electromagnetic fields for the human body is a growing concern for our society. We have previously shown that weak pulsed microwaves give rise to a significant leakage of albumin through the blood-brain barrier. In this study we investigated whether a pathologic leakage across the blood-brain barrier might be combined with damage to the neurons. Three groups each of eight rats were exposed for 2 hr to Global System for Mobile Communications (GSM) mobile phone electromagnetic fields of different strengths. We found highly significant (p< 0.002) evidence for neuronal damage in the cortex, hippocampus, and basal ganglia in the brains of exposed rats.


Asunto(s)
Encéfalo/efectos de la radiación , Teléfono Celular , Campos Electromagnéticos/efectos adversos , Neuronas/efectos de la radiación , Albúminas/metabolismo , Animales , Barrera Hematoencefálica/efectos de la radiación , Encéfalo/citología , Femenino , Masculino , Microondas/efectos adversos , Ratas , Ratas Endogámicas F344 , Suecia
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