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7 zeer interessante recente studies - juni 2012


Electromagnetic fields and health: DNA-based dosimetry


We propose a biologically based measure of EMF radiation to replace the energy-based “specific absorption rate” (SAR). A wide range of EMF frequencies has been linked to an increased risk of cancer. The SAR value used to measure the EMF dose and set the safety standard in the radiofrequency (RF) range fails as a standard for predicting cancer risk in the ELF power frequency range. Because cancers are believed to arise from mutations in DNA, changes in DNA induced by interaction with EMF could be a better measure of the biologically effective dose in both frequency ranges. The changes can be measured by transcriptional alterations and/or translational changes in specific proteins. Because ionizing radiation also causes DNA damage, a biologically based standard related to stimulation of DNA could apply over a much wider range of the electromagnetic spectrum. A safety standard for exposure to a wide range of non ionizing frequencies can be based on the documented changes in DNA biochemistry that arise from interactions with EMF.
http://informahealthcare.com/doi/abs/10.3109/15368378.2011.624662
Martin Blank, Reba M. Goodman. Electromagnetic fields and health: DNA-based dosimetry. Electromagn Biol Med. Posted online on June 7, 2012. (doi:10.3109/15368378.2011.
624662).

Address Correspondence to Martin Blank, Physiology and Cellular Biophysics, Columbia University, 630 W 168 St, New York, NY 10032, USA; E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.
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The effects of long-term exposure of magnetic field via 900-MHz GSM radiation on some biochemical parameters and brain histology in rats

Celikozlu SD, Ozyurt MS, Cimbiz A, Yardimoglu MY, Cayci MK, Ozay Y. The effects of long-term exposure of magnetic field via 900-MHz GSM radiation on some biochemical parameters and brain histology in rats. Electromagn Biol Med. 2012 Jun 7. [Epub ahead of print]

Address correspondence to Saadet D. Celikozlu, Altintas Meslek Yuksek Okulu, 43800, Altintas, Kutahya, Turkey. E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.

Abstract

The aim of this study is to determine the effects of magnetic field via cell phones on some blood parameters and neurons in the brain of rats. Animals have been classified into three groups: control, Magnetic Field (MF), and F2 groups. Throughout this study, cell phones were placed on the wall of the cages. Rats were exposed to the effects of cell phones during prenatal and postnatal periods until they were 80 days old. During the study, the exposure procedure of rats was that the phone was in standby mode for a whole day and in talking mode for 30 min per day. The waves of cell phones caused an increased blood glucose level from 96.52 ± 5.64 mg/dl to 132.14 ± 5.93 mg/dl and an increased serum protein level from 131.14 ± 6.19 mg/dl to 319.29 ± 6.73 mg/dl compared to control. Statistically, significant difference wasn't observed in the blood cholesterol concentration between the groups compared to the control. Weekly weight gain decreased in all groups compared to the control. MF exposure decreased pyramidal neuron numbers 51.15% and increased ischemic neuron numbers 73% at cortex region of brain. In addition, vascular dilatations have increased clearly in group F2. Whereas the procedure of MF did not have any effects on hippocampal pyramidal cell numbers, magnetic fields increased the amount of ischemic neurons three-fold compared to the control. In conclusion, MF affected some biochemical parameters, especially the cortex region of the brain.

PDF available at: http://akademikpersonel.kocaeli.edu.tr/melda/sci/melda03.04.2012_12.13.35sci.pdf

http://informahealthcare.com/doi/abs/10.3109/15368378.2012.662192

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Brain proteome response following whole body exposure of mice to mobile phone or wireless DECT base radiation

Adamantia F. Fragopoulou, Athina Samara, Marianna H. Antonelou, Anta Xanthopoulou, Aggeliki Papadopoulou, Konstantinos Vougas, Eugenia Koutsogiannopoulou, Ema Anastasiadou, Dimitrios J. Stravopodis, George Th. Tsangaris, Lukas H. Margaritis. Brain proteome response following whole body exposure of mice to mobile phone or wireless DECT base radiation. Posted online on January 20, 2012. (doi:10.3109/15368378.2011.631068)

Address correspondence to Lukas H. Margaritis, Adamantia F. Fragopoulou, Department of Cell Biology and Biophysics, Faculty of Biology, Athens University, Panepistimiopolis, 15784 Athens, Greece. E-mails: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken., Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.

The objective of this study was to investigate the effects of two sources of electromagnetic fields (EMFs) on the proteome of cerebellum, hippocampus, and frontal lobe in Balb/c mice following long-term whole body irradiation. Three equally divided groups of animals (6 animals/group) were used; the first group was exposed to a typical mobile phone, at a SAR level range of 0.17–0.37 W/kg for 3 h daily for 8 months, the second group was exposed to a wireless DECT base (Digital Enhanced Cordless Telecommunications/Telephone) at a SAR level range of 0.012–0.028 W/kg for 8 h/day also for 8 months and the third group comprised the sham-exposed animals. Comparative proteomics analysis revealed that long-term irradiation from both EMF sources altered significantly (p < 0.05) the expression of 143 proteins in total (as low as 0.003 fold downregulation up to 114 fold overexpression). Several neural function related proteins (i.e., Glial Fibrillary Acidic Protein (GFAP), Alpha-synuclein, Glia Maturation Factor beta (GMF), and apolipoprotein E (apoE)), heat shock proteins, and cytoskeletal proteins (i.e., Neurofilaments and tropomodulin) are included in this list as well as proteins of the brain metabolism (i.e., Aspartate aminotransferase, Glutamate dehydrogenase) to nearly all brain regions studied. Western blot analysis on selected proteins confirmed the proteomics data. The observed protein expression changes may be related to brain plasticity alterations, indicative of oxidative stress in the nervous system or involved in apoptosis and might potentially explain human health hazards reported so far, such as headaches, sleep disturbance, fatigue, memory deficits, and brain tumor long-term induction under similar exposure conditions.

http://informahealthcare.com/doi/abs/10.3109/15368378.2011.631068

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GSM 900 MHz radiation inhibits ants' association between food sites and encountered cues

Marie-Claire Cammaerts, Philippe De Doncker, Xavier Patris, François Bellens2, Zoheir Rachidi1, David Cammaerts. GSM 900 MHz radiation inhibits ants' association between food sites and encountered cues. Electromagn Biol Med. June 2012, Vol. 31, No. 2 , Pages 151-165 (doi:10.3109/15368378.2011.624661)

Address correspondence to Marie-Claire Cammaerts, Université Libre de Bruxelles, Faculté des Sciences, DBO, CP 160/12, 50 Av. F. Roosevelt, 1050 Bruxelles, Belgium; E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.

The kinetics of the acquisition and loss of the use of olfactory and visual cues were previously obtained in six experimental colonies of the ant Myrmica sabuleti meinert 1861, under normal conditions. In the present work, the same experiments were conducted on six other naive identical colonies of M. sabuleti, under electromagnetic radiation similar to those surrounding GSM and communication masts. In this situation, no association between food and either olfactory or visual cues occurred. After a recovery period, the ants were able to make such an association but never reached the expected score. Such ants having acquired a weaker olfactory or visual score and still undergoing olfactory or visual training were again submitted to electromagnetic waves. Not only did they lose all that they had memorized, but also they lost it in a few hours instead of in a few days (as under normal conditions when no longer trained). They kept no visual memory at all (instead of keeping 10% of it as they normally do). The impact of GSM 900 MHz radiation was greater on the visual memory than on the olfactory one. These communication waves may have such a disastrous impact on a wide range of insects using olfactory and/or visual memory, i.e., on bees.

http://informahealthcare.com/doi/abs/10.3109/15368378.2011.624661

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Study of the frequency parameters of EEG influenced by zone-dependent local ELF-MF exposure on the human head

S.A. Shafiei, S.M. Firoozabadi, K. Rasoulzadeh Tabatabaie, M. Ghabaee. Study of the frequency parameters of EEG influenced by zone-dependent local ELF-MF exposure on the human head. Electromagn Biol Med. June 2012, Vol. 31, No. 2 , Pages 112-121 (doi:10.3109/15368378.2011.624658)

Address correspondence to S.M. Firoozabadi, Department of Medical Physics, Tarbiat Modares University, Tehran, Iran; E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.

It has been reported that human subjects exposed to electromagnetic fields exhibit changes in human EEG signals at the frequency of stimulation. The aim of the present study was to expose different parts of the brain to extremely low-frequency magnetic fields locally and investigate EEG power spectrum alters at the frequency of stimulation. EEG relative power spectrum were evaluated at 3, 5, 10, 17, and 45 Hz frequencies at T4, T3, F3, Cz, and F4 points, respectively, when these points were exposed to magnetic fields with similar frequencies and 100 T intensity. The paired t-test results showed that power value of EEG did not alter significantly at the frequency of stimulation (P < 0.05). Further, significant changes in different EEG bands caused by locally exposing to ELF-MF in different points of brain were observed. The changes in the EEG bands were not limited necessarily to the exposure point.

http://informahealthcare.com/doi/abs/10.3109/15368378.2011.624658

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Investigation of the spinal cord as a natural receptor antenna for incident electromagnetic waves and possible impact on the central nervous system

Sevaiyan Balaguru, Rajan Uppal, Ravinder Pal Vaid, Balasubramaniam Preetham Kumar. Investigation of the spinal cord as a natural receptor antenna for incident electromagnetic waves and possible impact on the central nervous system. Electromagn Biol Med. June 2012, Vol. 31, No. 2 , Pages 101-111 (doi:10.3109/15368378.2011.624653)

Address correspondence to B. P. Kumar, Department of Electrical and Electronic Engineering, California State University, 6000 J Street, Sacramento, CA-95819-6019; E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken.

The effects of electromagnetic field (EMF) exposure on biological systems have been studied for many years, both as a source of medical therapy and also for potential health risks. In particular, the mechanisms of EMF absorption in the human or animal body is of medical/engineering interest, and modern modelling techniques, such as the Finite Difference Time Domain (FDTD), can be utilized to simulate the voltages and currents induced in different parts of the body. The simulation of one particular component, the spinal cord, is the focus of this article, and this study is motivated by the fact that the spinal cord can be modelled as a linear conducting structure, capable of generating a significant amount of voltage from incident EMF.

In this article, we show, through a FDTD simulation analysis of an incoming electromagnetic field (EMF), that the spinal cord acts as a natural antenna, with frequency dependent induced electric voltage and current distribution. The multi-frequency (100–2400 MHz) simulation results show that peak voltage and current response is observed in the FM radio range around 100 MHz, with significant strength to potentially cause changes in the CNS. This work can contribute to the understanding of the mechanism behind EMF energy leakage into the CNS, and the possible contribution of the latter energy leakage towards the weakening of the blood brain barrier (BBB), whose degradation is associated with the progress of many diseases, including Acquired Immuno-Deficiency Syndrome (AIDS).

http://informahealthcare.com/doi/abs/10.3109/15368378.2011.624653

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Measurement and analysis of electromagnetic pollution generated by GSM-900 mobile phone networks in Erciyes University, Turkey

Ugur Sorgucu, Ibrahim Develi. Measurement and analysis of electromagnetic pollution generated by GSM-900 mobile phone networks in Erciyes University, Turkey. Electromagn Biol Med. Posted online on June 7, 2012. (doi:10.3109/15368378.2012.683223)

Address correspondence to Ugur Sorgucu, Department of Electrical & Electronics Engineering, Faculty of Engineering, Bartin University, 74100, Bartin, Turkey. E-mail: Dit e-mailadres wordt beveiligd tegen spambots. JavaScript dient ingeschakeld te zijn om het te bekijken..

Mobile phones are becoming increasingly important in our everyday lives. The rising number of mobile phones reflects a similar increase in the number of base stations. Because of this rapid evolution, the establishment and planning of new base stations has become mandatory. However, the rise in the number of base stations, in terms of human health, is potentially very harmful. It is important to analyze the radiation levels of base stations until we can confirm that they are definitely not harmful in the long term. Mapping of electromagnetic field (EMF) is also important from a medical point of view because it provides useful information, for example, on the detection of diseases caused by EMF. With the help of this information the distribution of diseases over different regions can be obtained. In this article, the electromagnetic radiation levels of base stations were measured at 80 different points in Erciyes University (ERU), Turkey and detailed information about the measurement tools and measurement method were given. It was observed that no area in ERU exceeded the national and international limits. It is also observed that the effects of base stations vary according to duration and degree of exposure. Therefore, if people are exposed to a very low-intensity electromagnetic field for a very long time, serious health problems can occur.

http://informahealthcare.com/doi/abs/10.3109/15368378.2012.683223