... 10-8 G, uyarılmış durumda (0-100 Hz) 10-9 G; gözün manyetik alanı (0-10 Hz) 10-7 G; kalp kası... more ... 10-8 G, uyarılmış durumda (0-100 Hz) 10-9 G; gözün manyetik alanı (0-10 Hz) 10-7 G; kalp kası manyetik alanı (0-40 Hz) 2x10-6 G, iskelet kası manyetik alanı ise (1-100 Hz) 10-7 G şiddetindedir. ... Clin. Chim. Acta 2004; 340:153-62. 3. Meral I, Mert H, Mert N et al. ...
Most of the national and international organizations have formulated guidelines establishing limi... more Most of the national and international organizations have formulated guidelines establishing limits for occupational and residential EMF exposure. ICNIRP also developed the exposure limits for EMF. The international EMF project of WHO has completed a standards database limiting exposure to EMF. From this database it can be easily seen that the public safety level E field ranges between 3 V/m to 46.35 V/m for 900 MHz and between 6 V/m to 61.40 V/m for 1800 MHz. Some of the developed countries prefer to make their EMF standard as low as technically possible with "precautionary approach". For 900 MHz cellular phone frequency the E field limit value is 3 V/m in China, 3.88 V/m in Switzerland, 4 V/m in Italia, 0.614 V/m in Salzburg, Austria, 6.14 V/m in Bulgaria and Russia, and 10 V/m - 41.25 V/m in Turkey, 46.35 V/m in America, Canada and England and 41.25 V/m in other European Countries. Disparities in EMF standards around the world have now arisen the question that should al...
ABSTRACT Electromagnetic (EM) fields are generated by several natural and man-made sources. Part ... more ABSTRACT Electromagnetic (EM) fields are generated by several natural and man-made sources. Part of the electromagnetic spectrum called Radiofrequency (RF; 10 kHz – 300 GHz) is used in communications, mobile phones, radio and television broadcasts, etc. Extremely Low Frequency (ELF; 0 - 300 Hz) region of the spectrum is radiated by transformers, high power lines, household or working area appliances, and by the electrical goods. The use of electromagnetic waves increases due to the technological improvements, therefore, people are exposed to high levels of electromagnetic fields in their daily lives. The health priority of public concerns occurred about the mobile phones, base stations and wireless technologies. Furthermore, the sensitivity of the public is increasing on their adverse effects on the human health. The biological and health effects of EM radiation have been investigated for more than 25 years in Biophysics Department at Gazi University. In this study, the sources and the effects of EM fields along with the studies performed in Gazi Biophysics are summarized, and Gazi Non-Ionizing Radiation Protection Center (GNRK), the first scientific center founded to measure EM fields, is introduced. (Archives of Neuropsychiatry 2010; 47: 158-61)
Journal of Experimental and Clinical Medicine, 2013
This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 o... more This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 or 4 hrs) to Enhanced Data rates for Global System for Mobile Communication Evolution (GSM-EDGE) modulated radiofrequency radiation (RFR) at 900 MHz and 1800 MHz frequencies on the viability of the hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt [2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium] (WST-1) by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4,6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour-exposure produced more pronounced effects than the other exposure durations. 1800-MHz RFR had more impact on cell viability and injury of Hep G2 than the RFR at 900 MHz. Morphological observations also supported the biochemical results that most of the cells showed irregular nuclei pattern as a marker of late stage apoptosis using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 hrs of exposure to 1800-MHz RFR. The results showed that proliferation of Hep G2 cells increased after 1 hour of exposure whereas a decrease was observed after four hours of-exposure to the 1800-MHz radiation. The 900-MHz radiation had no significant effect on cell proliferation after 1 hour of exposure, but a decrease was observed after 4 hrs of exposure. Further studies will involve other frequency bands of RFR and longer duration of exposure.
Biological effects of static electric and 50-Hz electric (E) and magnetic (B) fields with intensi... more Biological effects of static electric and 50-Hz electric (E) and magnetic (B) fields with intensities similar to occupational exposure have been analyzed at the Bioelectromagnetic Laboratory of Biophysics Department in the Medical Faculty of Gazi University for more than 25 years. A principal aim of this review is to evaluate the results of our in vivo studies. Static electric field in the range of 0.3-1.9 kV/m (0.3, 0.6, 0.8, 0.9, 1.35, 1.8, 1.9 kV/m) and ELF electric field in the range of 1.35-12 kV/m (1.35, 2, 2.5, 3, 3.5, 4, 4.5, 5, 12 kV/m) were applied to lab animals, directions (vertical and horizontal) and exposure periods (4-8 h/day, for 1, 3, 5, 7, 10 days). ELF magnetic fields were also applied with intensities of 1, 1.5, 2, and 3 mT. Magnetic field exposure periods were 4 h/day for 4, 5 or 7 days and 8 h/day for 5 days. Under the above exposure conditions, cellular enzymatic activities (SOD, GSH-Px, MPO, CAT, ADA and XO) and free radicals (MDA and NOx) were analyzed in t...
ELF Magnetic (B) fields and Static Electric (E) fields effects on different tissues of Guinea pig... more ELF Magnetic (B) fields and Static Electric (E) fields effects on different tissues of Guinea pigs and mice in laboratory conditions were carried out at the Bioelectromagnetic Laboratory of Biophysics Department in Medical Faculty of Gazi University. Effects of Static Electric (E) fields (0.3 kV/m, 0.9 kV/m, 1.8 kV/m and 1.9 kV/m) generated from a specially designed parallel plate capacitor system were studied on collagen synthesis, free oxygen radicals and antioxidant enzyme. The guinea pigs were exposed to E fields for 3 days, 9 hours/day (between 8 a.m. and 5 p.m.) in wooden cages with copper plates mounted vertically or horizontally over them. Effects of magnetic fields (50 Hz, 2 G and 20 G) generated from a specially designed Helmholtz coil system were studied on brain and plasma electrolytes, immune system (NK cell) and epilepsy. The duration of test sessions were 4 hours (5 days). The results of these studies indicated that ELF Magnetic (B) fields and Static Electric fields h...
2003 IEEE International Symposium on Electromagnetic Compatibility, 2003. EMC '03., 2003
ABSTRACT Dosimetry is necessary to scale exposures across species to compare biological responses... more ABSTRACT Dosimetry is necessary to scale exposures across species to compare biological responses. The functionally equivalent exposure of a human is estimated from animal exposure by dosimetry. Induced electric fields and current densities were calculated for 50 Hz, 10 G, 20 G and 30 G magnetic fields exposures using ellipsoid models representing human standing and guinea pig on all four feet on the ground. E fields induced by 10 G, 20 G and 30 G fields of 50 Hz were calculated as 4.04 mV/m, 8.07 mV/m and 12.11 mV/m respectively for guinea pigs. For the human model these fields were found 12.5 mV/m, 25 mV/m and 37.7 mV/m. Induced current densities were calculated between 0.404 mA/m2 and 1.211 mA/m2 for guinea pig, between 1.25 mA/m2 and 3.77 mA/m2 for human by taking the conductivity 0.1 S/m. Average value of human: guinea pig ratios (scaling factor - SF) was calculated as 3.1. The functionally equivalent exposure of human was obtained from SF of 3.1 and found between 3.23 G and 9.68 G.
... _____ * To whom correspondence should be addressed: Nesrin Seyhan, Gazi University Faculty of... more ... _____ * To whom correspondence should be addressed: Nesrin Seyhan, Gazi University Faculty of Medicine, Đ 2006 Springer. ... NK cell activity was evaluated by natural anticandidial colorimetric index according to Öztürk et. al.'s method in spleen tissues of Guinea pigs33. ...
Journal of Experimental and Clinical Medicine, 2013
This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 o... more This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 or 4 hrs) to Enhanced Data rates for Global System for Mobile Communication Evolution (GSM-EDGE) modulated radiofrequency radiation (RFR) at 900 MHz and 1800 MHz frequencies on the viability of the hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt [2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium] (WST-1) by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4,6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour-exposure produced more pronounced effects than the other exposure durations. 1800-MHz RFR had more impact on cell viability and injury of Hep G2 than the RFR at 900 MHz. Morphological observations also supported the biochemical results that most of the cells showed irregular nuclei pattern as a marker of late stage apoptosis using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 hrs of exposure to 1800-MHz RFR. The results showed that proliferation of Hep G2 cells increased after 1 hour of exposure whereas a decrease was observed after four hours of-exposure to the 1800-MHz radiation. The 900-MHz radiation had no significant effect on cell proliferation after 1 hour of exposure, but a decrease was observed after 4 hrs of exposure. Further studies will involve other frequency bands of RFR and longer duration of exposure.
In order to test whether antioxidants have beneficiary effects on electric field induced damage, ... more In order to test whether antioxidants have beneficiary effects on electric field induced damage, we determined the pulmonary levels of heme oxygenase-1 (HO-1), protein carbonyl content (PCO), malondialdehyde (MDA), nitric oxide (NO) and hydroxyproline (HP) under extremely low frequency (ELF) electric (E) field exposure (50 Hz, 12 kV/m, 7 days/for 8 h/day). While PCO levels significantly increased (p<0.05), insignificant changes (p>0.05) were observed in HO-1, MDA, NO and HP levels for electric field exposure groups compared to the control group. We have not observed any significant change in these parameters on the electric field group compared to the group where NAC and EGCG were separately applied along with electric field. However, during our previous studies, we have concluded that NAC and EGCG are potent antioxidants and we believe that new studies should be established by way of setting up different experimental conditions.
To investigate whether pre- and post-drug magnetic field (MF) exposure of 50 Hz, 0.2 mT has any s... more To investigate whether pre- and post-drug magnetic field (MF) exposure of 50 Hz, 0.2 mT has any significant effect on pentylenetetrazol (PTZ)-induced seizures in mice. MF was generated by a pair of Helmholtz coils. Seizures were induced by PTZ injection intraperitoneally (i.p.) at a dose of 60 mg/kg. A total of 48 locally bred adult female mice 25-35 g in weight were used. Latency to seizure, total seizure duration, and mortality were recorded for each mouse. Neither pre- nor post-drug exposure to a 50 Hz, 0.2 mT MF was found to have any effect on PTZ-induced epileptic seizures or mortality rates in mice. The present study failed to provide any support for a therapeutic potential of a 50 Hz, 0.2 mT MF for epilepsy.
In vivo effects of Static Electric and ELF Magnetic and Electric fields have been carried out for... more In vivo effects of Static Electric and ELF Magnetic and Electric fields have been carried out for more than 20 years in the Bioelectromagnetic Laboratory at the Biophysics Department of the Medical Faculty of Gazi University. In this article, the results of in vivo ELF Electric field studies are presented as a review. Static and 50 Hz ELF (Extremely Low Frequency) Electric (E) fields effects on free radical synthesis, antioxidant enzyme level, and collagen synthesis were analyzed on tissues of guinea pigs, such as brain, liver, lung, kidney, spleen, testis, and plasma. Animals were exposed to static and ELF electric fields with intensities ranging from 0.3 kV/m to 1.9 kV/m in vertical and horizontal directions. Exposure periods were 1, 3, 5, 7, and 10 days. Electric fields were generated from a specially designed parallel plate capacitor system. The results indicate that the effects of electric fields on the tissues studied depend significantly on the type and magnitude of electric field and exposure period.
In this study, the results related with the effects of 50 Hz, 0.2 mT-3 mT MFs exposures on collag... more In this study, the results related with the effects of 50 Hz, 0.2 mT-3 mT MFs exposures on collagen synthesis, epilepsy, electrolytes, lipid peroxidation (MDA), Nitric Oxide (NOx), respiratory burst system (MPO), antioxidant defense system (GSH), and immune system (NK cell activity) in spleen, skin, lung, kidney, brain, and plasma tissues performed at Gazi Biophysics Department are reviewed. Our studies indicate that ELF MFs had effects on the tissues examined.
The present study was carried out to investigate the potential effects of ELF (extremely low freq... more The present study was carried out to investigate the potential effects of ELF (extremely low frequency) electric field exposure on generating free radicals in guinea pigs. For this purpose, we determined thiobarbituric acid reactive substances (TBARS) levels, one of the byproducts of lipid peroxidation, the changes of the activities of superoxide dismutase (SOD), as an antioxidant enzyme, and gamma-Glutamyl transferase (GGT) as the key enzyme in GSH metabolism. Moreover, in order to investigate electric field effects on functions of organs, we measured the alanine aminotransferase (ALT) activity, alkaline phosphatase (ALP) activity, lactate dehydrogenase (LDH) activity, total cholesterol (TC), LDL cholesterol, HDL cholesterol, VLDL cholesterol, triglycerides (TG), urea, uric acid, creatin, glucose, and blood-urea nitrogen (BUN) in serum of guinea pigs exposed to different intensities and directions electric fields. In this study we have found that vertical and horizontal application of ELF electric fields in the range of 1.35, 1.5, and 1.8 kV/m increased TBARS and SOD levels as compared to the controls (p < 0.05) and to applied electric fields of 0.3, 0.6, 0.8, and 1 kV/m. On the other hand, other serum levels of some biochemical parameters that were also investigated did not undergo statistically significant changes (p > 0.05).
The purpose of this study was to reveal the apoptotic cell formation, using histopathological and... more The purpose of this study was to reveal the apoptotic cell formation, using histopathological and immunohistochemical methods, in non-pregnant and pregnant New Zealand White rabbits, and in offspring of the pregnant group exposed to GSM modulated signal in 1,800 MHz frequency. Apoptotic cells were detected in the brain, eyes, kidneys, liver, lung, heart, and spleen by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) staining. Histopathological changes were observed in the examined organs. TUNEL positivity was seen in the brain (group VI) and eyes (groups IV and VI). In groups I, II, III, and V, the positivity was lesser than 5% and was not taken into account.
We aimed to evaluate the effect of 2100MHz radiofrequency radiation emitted by a generator, simul... more We aimed to evaluate the effect of 2100MHz radiofrequency radiation emitted by a generator, simulating a 3G-mobile phone on the brain of rats during 10 and 40 days of exposure. The female rats were randomly divided into four groups. Group I; exposed to 3G modulated 2100MHz RFR signal for 6h/day, 5 consecutive days/wk for 2 weeks, group II; control 10 days, were kept in an inactive exposure set-up for 6h/day, 5 consecutive days/wk for 2 weeks, group III; exposed to 3G modulated 2100MHz RFR signal for 6h/day, 5 consecutive days/wk for 8 weeks and group IV; control 40 days, were kept in an inactive exposure set-up for 6h/day, 5 consecutive days/wk for 8 weeks. After the genomic DNA content of brain was extracted, oxidative DNA damage (8-hydroxy-2'deoxyguanosine, pg/mL) and malondialdehyde (MDA, nmoL/g tissue) levels were determined. Our main finding was the increased oxidative DNA damage to brain after 10 days of exposure with the decreased oxidative DNA damage following 40 days of exposure compared to their control groups. Besides decreased lipid peroxidation end product, MDA, was observed after 40 days of exposure. The measured decreased quantities of damage during the 40 days of exposure could be the means of adapted and increased DNA repair mechanisms.
With the increased use of mobile phones, their biological and health effects have become more imp... more With the increased use of mobile phones, their biological and health effects have become more important. Usage of mobile phones near the head increases the possibility of effects on brain tissue. This study was designed to investigate the possible effects of pulse modulated 900MHz and 1800MHz radio-frequency radiation on the permeability of blood-brain barrier of rats. Study was performed with 6 groups of young adult male and female wistar albino rats. The permeability of blood-brain barrier to intravenously injected evans blue dye was quantitatively examined for both control and radio-frequency radiarion exposed groups. For male groups; Evans blue content in the whole brain was found to be 0.08±0.01mg% in the control, 0.13±0.03mg% in 900MHz exposed and 0.26±0.05mg% in 1800MHz exposed animals. In both male radio-frequency radiation exposed groups, the permeability of blood-brain barrier found to be increased with respect to the controls (p<0.01). 1800MHz pulse modulated radio-fre...
... 10-8 G, uyarılmış durumda (0-100 Hz) 10-9 G; gözün manyetik alanı (0-10 Hz) 10-7 G; kalp kası... more ... 10-8 G, uyarılmış durumda (0-100 Hz) 10-9 G; gözün manyetik alanı (0-10 Hz) 10-7 G; kalp kası manyetik alanı (0-40 Hz) 2x10-6 G, iskelet kası manyetik alanı ise (1-100 Hz) 10-7 G şiddetindedir. ... Clin. Chim. Acta 2004; 340:153-62. 3. Meral I, Mert H, Mert N et al. ...
Most of the national and international organizations have formulated guidelines establishing limi... more Most of the national and international organizations have formulated guidelines establishing limits for occupational and residential EMF exposure. ICNIRP also developed the exposure limits for EMF. The international EMF project of WHO has completed a standards database limiting exposure to EMF. From this database it can be easily seen that the public safety level E field ranges between 3 V/m to 46.35 V/m for 900 MHz and between 6 V/m to 61.40 V/m for 1800 MHz. Some of the developed countries prefer to make their EMF standard as low as technically possible with "precautionary approach". For 900 MHz cellular phone frequency the E field limit value is 3 V/m in China, 3.88 V/m in Switzerland, 4 V/m in Italia, 0.614 V/m in Salzburg, Austria, 6.14 V/m in Bulgaria and Russia, and 10 V/m - 41.25 V/m in Turkey, 46.35 V/m in America, Canada and England and 41.25 V/m in other European Countries. Disparities in EMF standards around the world have now arisen the question that should al...
ABSTRACT Electromagnetic (EM) fields are generated by several natural and man-made sources. Part ... more ABSTRACT Electromagnetic (EM) fields are generated by several natural and man-made sources. Part of the electromagnetic spectrum called Radiofrequency (RF; 10 kHz – 300 GHz) is used in communications, mobile phones, radio and television broadcasts, etc. Extremely Low Frequency (ELF; 0 - 300 Hz) region of the spectrum is radiated by transformers, high power lines, household or working area appliances, and by the electrical goods. The use of electromagnetic waves increases due to the technological improvements, therefore, people are exposed to high levels of electromagnetic fields in their daily lives. The health priority of public concerns occurred about the mobile phones, base stations and wireless technologies. Furthermore, the sensitivity of the public is increasing on their adverse effects on the human health. The biological and health effects of EM radiation have been investigated for more than 25 years in Biophysics Department at Gazi University. In this study, the sources and the effects of EM fields along with the studies performed in Gazi Biophysics are summarized, and Gazi Non-Ionizing Radiation Protection Center (GNRK), the first scientific center founded to measure EM fields, is introduced. (Archives of Neuropsychiatry 2010; 47: 158-61)
Journal of Experimental and Clinical Medicine, 2013
This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 o... more This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 or 4 hrs) to Enhanced Data rates for Global System for Mobile Communication Evolution (GSM-EDGE) modulated radiofrequency radiation (RFR) at 900 MHz and 1800 MHz frequencies on the viability of the hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt [2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium] (WST-1) by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4,6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour-exposure produced more pronounced effects than the other exposure durations. 1800-MHz RFR had more impact on cell viability and injury of Hep G2 than the RFR at 900 MHz. Morphological observations also supported the biochemical results that most of the cells showed irregular nuclei pattern as a marker of late stage apoptosis using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 hrs of exposure to 1800-MHz RFR. The results showed that proliferation of Hep G2 cells increased after 1 hour of exposure whereas a decrease was observed after four hours of-exposure to the 1800-MHz radiation. The 900-MHz radiation had no significant effect on cell proliferation after 1 hour of exposure, but a decrease was observed after 4 hrs of exposure. Further studies will involve other frequency bands of RFR and longer duration of exposure.
Biological effects of static electric and 50-Hz electric (E) and magnetic (B) fields with intensi... more Biological effects of static electric and 50-Hz electric (E) and magnetic (B) fields with intensities similar to occupational exposure have been analyzed at the Bioelectromagnetic Laboratory of Biophysics Department in the Medical Faculty of Gazi University for more than 25 years. A principal aim of this review is to evaluate the results of our in vivo studies. Static electric field in the range of 0.3-1.9 kV/m (0.3, 0.6, 0.8, 0.9, 1.35, 1.8, 1.9 kV/m) and ELF electric field in the range of 1.35-12 kV/m (1.35, 2, 2.5, 3, 3.5, 4, 4.5, 5, 12 kV/m) were applied to lab animals, directions (vertical and horizontal) and exposure periods (4-8 h/day, for 1, 3, 5, 7, 10 days). ELF magnetic fields were also applied with intensities of 1, 1.5, 2, and 3 mT. Magnetic field exposure periods were 4 h/day for 4, 5 or 7 days and 8 h/day for 5 days. Under the above exposure conditions, cellular enzymatic activities (SOD, GSH-Px, MPO, CAT, ADA and XO) and free radicals (MDA and NOx) were analyzed in t...
ELF Magnetic (B) fields and Static Electric (E) fields effects on different tissues of Guinea pig... more ELF Magnetic (B) fields and Static Electric (E) fields effects on different tissues of Guinea pigs and mice in laboratory conditions were carried out at the Bioelectromagnetic Laboratory of Biophysics Department in Medical Faculty of Gazi University. Effects of Static Electric (E) fields (0.3 kV/m, 0.9 kV/m, 1.8 kV/m and 1.9 kV/m) generated from a specially designed parallel plate capacitor system were studied on collagen synthesis, free oxygen radicals and antioxidant enzyme. The guinea pigs were exposed to E fields for 3 days, 9 hours/day (between 8 a.m. and 5 p.m.) in wooden cages with copper plates mounted vertically or horizontally over them. Effects of magnetic fields (50 Hz, 2 G and 20 G) generated from a specially designed Helmholtz coil system were studied on brain and plasma electrolytes, immune system (NK cell) and epilepsy. The duration of test sessions were 4 hours (5 days). The results of these studies indicated that ELF Magnetic (B) fields and Static Electric fields h...
2003 IEEE International Symposium on Electromagnetic Compatibility, 2003. EMC '03., 2003
ABSTRACT Dosimetry is necessary to scale exposures across species to compare biological responses... more ABSTRACT Dosimetry is necessary to scale exposures across species to compare biological responses. The functionally equivalent exposure of a human is estimated from animal exposure by dosimetry. Induced electric fields and current densities were calculated for 50 Hz, 10 G, 20 G and 30 G magnetic fields exposures using ellipsoid models representing human standing and guinea pig on all four feet on the ground. E fields induced by 10 G, 20 G and 30 G fields of 50 Hz were calculated as 4.04 mV/m, 8.07 mV/m and 12.11 mV/m respectively for guinea pigs. For the human model these fields were found 12.5 mV/m, 25 mV/m and 37.7 mV/m. Induced current densities were calculated between 0.404 mA/m2 and 1.211 mA/m2 for guinea pig, between 1.25 mA/m2 and 3.77 mA/m2 for human by taking the conductivity 0.1 S/m. Average value of human: guinea pig ratios (scaling factor - SF) was calculated as 3.1. The functionally equivalent exposure of human was obtained from SF of 3.1 and found between 3.23 G and 9.68 G.
... _____ * To whom correspondence should be addressed: Nesrin Seyhan, Gazi University Faculty of... more ... _____ * To whom correspondence should be addressed: Nesrin Seyhan, Gazi University Faculty of Medicine, Đ 2006 Springer. ... NK cell activity was evaluated by natural anticandidial colorimetric index according to Öztürk et. al.&#x27;s method in spleen tissues of Guinea pigs33. ...
Journal of Experimental and Clinical Medicine, 2013
This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 o... more This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3 or 4 hrs) to Enhanced Data rates for Global System for Mobile Communication Evolution (GSM-EDGE) modulated radiofrequency radiation (RFR) at 900 MHz and 1800 MHz frequencies on the viability of the hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt [2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium] (WST-1) by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4,6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour-exposure produced more pronounced effects than the other exposure durations. 1800-MHz RFR had more impact on cell viability and injury of Hep G2 than the RFR at 900 MHz. Morphological observations also supported the biochemical results that most of the cells showed irregular nuclei pattern as a marker of late stage apoptosis using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 hrs of exposure to 1800-MHz RFR. The results showed that proliferation of Hep G2 cells increased after 1 hour of exposure whereas a decrease was observed after four hours of-exposure to the 1800-MHz radiation. The 900-MHz radiation had no significant effect on cell proliferation after 1 hour of exposure, but a decrease was observed after 4 hrs of exposure. Further studies will involve other frequency bands of RFR and longer duration of exposure.
In order to test whether antioxidants have beneficiary effects on electric field induced damage, ... more In order to test whether antioxidants have beneficiary effects on electric field induced damage, we determined the pulmonary levels of heme oxygenase-1 (HO-1), protein carbonyl content (PCO), malondialdehyde (MDA), nitric oxide (NO) and hydroxyproline (HP) under extremely low frequency (ELF) electric (E) field exposure (50 Hz, 12 kV/m, 7 days/for 8 h/day). While PCO levels significantly increased (p&amp;amp;amp;amp;amp;amp;lt;0.05), insignificant changes (p&amp;amp;amp;amp;amp;amp;gt;0.05) were observed in HO-1, MDA, NO and HP levels for electric field exposure groups compared to the control group. We have not observed any significant change in these parameters on the electric field group compared to the group where NAC and EGCG were separately applied along with electric field. However, during our previous studies, we have concluded that NAC and EGCG are potent antioxidants and we believe that new studies should be established by way of setting up different experimental conditions.
To investigate whether pre- and post-drug magnetic field (MF) exposure of 50 Hz, 0.2 mT has any s... more To investigate whether pre- and post-drug magnetic field (MF) exposure of 50 Hz, 0.2 mT has any significant effect on pentylenetetrazol (PTZ)-induced seizures in mice. MF was generated by a pair of Helmholtz coils. Seizures were induced by PTZ injection intraperitoneally (i.p.) at a dose of 60 mg/kg. A total of 48 locally bred adult female mice 25-35 g in weight were used. Latency to seizure, total seizure duration, and mortality were recorded for each mouse. Neither pre- nor post-drug exposure to a 50 Hz, 0.2 mT MF was found to have any effect on PTZ-induced epileptic seizures or mortality rates in mice. The present study failed to provide any support for a therapeutic potential of a 50 Hz, 0.2 mT MF for epilepsy.
In vivo effects of Static Electric and ELF Magnetic and Electric fields have been carried out for... more In vivo effects of Static Electric and ELF Magnetic and Electric fields have been carried out for more than 20 years in the Bioelectromagnetic Laboratory at the Biophysics Department of the Medical Faculty of Gazi University. In this article, the results of in vivo ELF Electric field studies are presented as a review. Static and 50 Hz ELF (Extremely Low Frequency) Electric (E) fields effects on free radical synthesis, antioxidant enzyme level, and collagen synthesis were analyzed on tissues of guinea pigs, such as brain, liver, lung, kidney, spleen, testis, and plasma. Animals were exposed to static and ELF electric fields with intensities ranging from 0.3 kV/m to 1.9 kV/m in vertical and horizontal directions. Exposure periods were 1, 3, 5, 7, and 10 days. Electric fields were generated from a specially designed parallel plate capacitor system. The results indicate that the effects of electric fields on the tissues studied depend significantly on the type and magnitude of electric field and exposure period.
In this study, the results related with the effects of 50 Hz, 0.2 mT-3 mT MFs exposures on collag... more In this study, the results related with the effects of 50 Hz, 0.2 mT-3 mT MFs exposures on collagen synthesis, epilepsy, electrolytes, lipid peroxidation (MDA), Nitric Oxide (NOx), respiratory burst system (MPO), antioxidant defense system (GSH), and immune system (NK cell activity) in spleen, skin, lung, kidney, brain, and plasma tissues performed at Gazi Biophysics Department are reviewed. Our studies indicate that ELF MFs had effects on the tissues examined.
The present study was carried out to investigate the potential effects of ELF (extremely low freq... more The present study was carried out to investigate the potential effects of ELF (extremely low frequency) electric field exposure on generating free radicals in guinea pigs. For this purpose, we determined thiobarbituric acid reactive substances (TBARS) levels, one of the byproducts of lipid peroxidation, the changes of the activities of superoxide dismutase (SOD), as an antioxidant enzyme, and gamma-Glutamyl transferase (GGT) as the key enzyme in GSH metabolism. Moreover, in order to investigate electric field effects on functions of organs, we measured the alanine aminotransferase (ALT) activity, alkaline phosphatase (ALP) activity, lactate dehydrogenase (LDH) activity, total cholesterol (TC), LDL cholesterol, HDL cholesterol, VLDL cholesterol, triglycerides (TG), urea, uric acid, creatin, glucose, and blood-urea nitrogen (BUN) in serum of guinea pigs exposed to different intensities and directions electric fields. In this study we have found that vertical and horizontal application of ELF electric fields in the range of 1.35, 1.5, and 1.8 kV/m increased TBARS and SOD levels as compared to the controls (p &amp;amp;amp;amp;lt; 0.05) and to applied electric fields of 0.3, 0.6, 0.8, and 1 kV/m. On the other hand, other serum levels of some biochemical parameters that were also investigated did not undergo statistically significant changes (p &amp;amp;amp;amp;gt; 0.05).
The purpose of this study was to reveal the apoptotic cell formation, using histopathological and... more The purpose of this study was to reveal the apoptotic cell formation, using histopathological and immunohistochemical methods, in non-pregnant and pregnant New Zealand White rabbits, and in offspring of the pregnant group exposed to GSM modulated signal in 1,800 MHz frequency. Apoptotic cells were detected in the brain, eyes, kidneys, liver, lung, heart, and spleen by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) staining. Histopathological changes were observed in the examined organs. TUNEL positivity was seen in the brain (group VI) and eyes (groups IV and VI). In groups I, II, III, and V, the positivity was lesser than 5% and was not taken into account.
We aimed to evaluate the effect of 2100MHz radiofrequency radiation emitted by a generator, simul... more We aimed to evaluate the effect of 2100MHz radiofrequency radiation emitted by a generator, simulating a 3G-mobile phone on the brain of rats during 10 and 40 days of exposure. The female rats were randomly divided into four groups. Group I; exposed to 3G modulated 2100MHz RFR signal for 6h/day, 5 consecutive days/wk for 2 weeks, group II; control 10 days, were kept in an inactive exposure set-up for 6h/day, 5 consecutive days/wk for 2 weeks, group III; exposed to 3G modulated 2100MHz RFR signal for 6h/day, 5 consecutive days/wk for 8 weeks and group IV; control 40 days, were kept in an inactive exposure set-up for 6h/day, 5 consecutive days/wk for 8 weeks. After the genomic DNA content of brain was extracted, oxidative DNA damage (8-hydroxy-2&amp;amp;amp;amp;#39;deoxyguanosine, pg/mL) and malondialdehyde (MDA, nmoL/g tissue) levels were determined. Our main finding was the increased oxidative DNA damage to brain after 10 days of exposure with the decreased oxidative DNA damage following 40 days of exposure compared to their control groups. Besides decreased lipid peroxidation end product, MDA, was observed after 40 days of exposure. The measured decreased quantities of damage during the 40 days of exposure could be the means of adapted and increased DNA repair mechanisms.
With the increased use of mobile phones, their biological and health effects have become more imp... more With the increased use of mobile phones, their biological and health effects have become more important. Usage of mobile phones near the head increases the possibility of effects on brain tissue. This study was designed to investigate the possible effects of pulse modulated 900MHz and 1800MHz radio-frequency radiation on the permeability of blood-brain barrier of rats. Study was performed with 6 groups of young adult male and female wistar albino rats. The permeability of blood-brain barrier to intravenously injected evans blue dye was quantitatively examined for both control and radio-frequency radiarion exposed groups. For male groups; Evans blue content in the whole brain was found to be 0.08±0.01mg% in the control, 0.13±0.03mg% in 900MHz exposed and 0.26±0.05mg% in 1800MHz exposed animals. In both male radio-frequency radiation exposed groups, the permeability of blood-brain barrier found to be increased with respect to the controls (p<0.01). 1800MHz pulse modulated radio-fre...
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