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Öğe Distortion Product Otoacoustic Emissions in Infant, Pregnant and Non-pregnant Adult Rabbits: Comparison for Different Stimulus Levels(Aves, 2011) Muluk, Nuray Bayar; Budak, Gurer G.; Budak, Bilgehan; Apan, Alpaslan; Ozturk, Goknur Guler; Seyhan, NesrinObjectives: In the present study, we investigated Distortion Product Otoacoustic Emissions in pregnant (Group 1); non-pregnat adult female rabbits (Group 2) and infant rabbits (Group 3). We assessed Distortion Product Otoacoustic Emission amplitudes in both stimulus levels of F2/F1=1.22 and 1.14; and analyzed the amplitude differences in different groups. Methods: Thirty-six New Zealand White rabbits were included into the study. They were divided into three groups. Group 1 consisted of 9 each 13-month-old, adult, pregnant female rabbits. Group 2 consisted of 9 each 13-month-old, adult, nonpregnant female rabbits. Group 3 consisted of 18 each one-month-old, infant rabbits (Nine of them, male; and nine of them, female). In all groups, cochlear functions were assessed by Distortion Product Otoacoustic Emissions at 1.0-8.0 kHz. Stimulus parameters were used as F2/F1=1.22 in the first recording; and 1.14, in the second recording for each of the ears. Results: In all groups (1 to 3), Distortion Product Otoacoustic Emission amplitudes were found as higher with F2/F1:1.22 measurements than F2/F1:1.14 measurements. In F2/F1:1.22; and F2/F1:1.14 measurements seperately; at each Distortion Product Otoacoustic Emission frequencies (1.0-8.0 kHz), the difference between Distortion Product Otoacoustic Emission amplitudes of Group1-3 were analyzed by "Kruskal Wallis Variance Analysis": The statistically significant difference were present at frequencies of 1.5-2.0 kHz and 8.0 kHz for F2/F1:1.22 measurements; and 1.0-2.0 kHz and 4.0-8.0 kHz for F2/F1:1.14 measurements. In F2/F1:1.22 measurements, at 1.5 kHz, the mean value of Group 1 (Pregnant rabbits) was significantly higher than that of Group 3 (Infant rabbits). In F2/F1:1,14 measurements, at 1.0, 4.0 and 8.0 khz, the mean values of Group 1 (Pregnant rabbits) was significantly higher than those of Group 3 (Infant rabbits); and at 1.0, 2.0 and 4.0 kHz, the mean values of Group 2 (Non-pregnant rabbits) were significantly higher than those of Group 3 (Infant rabbits) Conclusion: Our study demonstrated that, in pregnant rabbits, higher corticosteroid levels may cause higher DPOAE amplitudes than infant rabbits by F2/F1:1.14 measurements. In all rabbits and especially in infant rabbits, Distortion Product Otoacoustic Emissions could be taken by F2/F1:1.22 measurements with higher amplitudes. The importance of our study is, when Distortion Product Otoacoustic Emission measurement is planned, measurements should be done using F2/F1: 1.22 to get healthy and accurate results in experimental studies. In measurements made by F2/F1: 1.14, amplitudes can be observed as lower than F2/F1: 1.22 measurements. This decline is evident especially in infant rabbit groups. Water containing medium in the middle ear of infant rabbits may cause the reduce in Distortion Product Otoacoustic Emission amplitudes than adult rabbits at both F2/F1:1.22 and 1.14 measurements.Öğe Effects of cell phone radiation on lipid peroxidation, glutathione and nitric oxide levels in mouse brain during epileptic seizure(Elsevier Science Bv, 2016) Esmekaya, Meric Arda; Tuysuz, Mehmet Zahid; Tomruk, Arin; Canseven, Ayse G.; Yucel, Engin; Aktuna, Zuhal; Seyhan, NesrinThe objective of the this study was to evaluate the effects of cellular phone radiation on oxidative stress parameters and oxide levels in mouse brain during pentylenetetrazole (PTZ) induced epileptic seizure. Eight weeks old mice were used in the study. Animals were distributed in the following groups: Group I: Control group treated with PTZ, Group II: 15 min cellular phone radiation + PTZ treatment + 30 min cellular phone radiation, Group III: 30 min cellular phone radiation + PTZ treatment + 30 min cellular phone radiation. The RF radiation was produced by a 900 MHz cellular phone. Lipid peroxidation, which is the indicator of oxidative stress was quantified by measuring the formation of thiobarbituric acid reactive substances (TBARS). The glutathione (GSH) levels were determined by the Ellman method. Tissue total nitric oxide (NOx) levels were obtained using the Griess assay. Lipid peroxidation and NOx levels of brain tissue increased significantly in group II and III compared to group I. On the contrary, GSH levels were significantly lower in group II and III than group I. However, no statistically significant alterations in any of the endpoints were noted between group II and Group III. Overall, the experimental findings demonstrated that cellular phone radiation may increase the oxidative damage and NOx level during epileptic activity in mouse brain. (C) 2016 Elsevier B.V. All rights reserved.Öğe Effects of extremely low frequency electromagnetic fields on distortion product otoacoustic emissions in rabbits(Elsevier Sci Ltd, 2009) Budak, Bilgehan; Budak, Gürer G.; Öztürk, Göknur Güler; Muluk, Nuray Bayar; Apan, Alpaslan; Seyhan, NesrinObjective: Humans are continuously exposed to extremely low frequency (ELF), electromagnetic fields (EMF), transmitted from the common Sources like power stations, electric transmission lines, communication and radio-television signal transmission units. The present study aimed to assess the effects of 50 Hz ELF-EMF of 5.068 and 10.182 kV/m electric fields, which refer to the lower and upper intensity limits beyond which hazardous effects can be observed, on the auditory functions of rabbits via Distortion Product Otoacoustic Emission (DPOAE) recordings. Methods: The study was performed on 20 healthy adult female New Zealand White rabbits randomly divided into two groups and applied 50 Hz ELF-EMF with either 5.068 kV/m (Group 1) or 10.182 kV/m (Group 2) of electric field for 3 h/day during 14 days. DPOAE responses recorded on the 0th day before exposure (B-EMF) and on the 6th (A-EMF-6th) and 14th (A-EMF-14th) days after exposure (AE). Mean stimulus intensity and emission amplitudes at 1.0-8.0 kHz were analyzed. Results: In Group 2 rabbits, on 6th and 14th days, the DPOAE amplitudes were observed as increased at 1.5-4.0 kHz (at 2.0 and 4.0 kHz significantly) than B-EMF values. At 6.0 kHz, A-EMF-14th amplitudes were significantly lower than A-EMF values. Conclusion: These results suggest that ELF EMFs might affect hearing functions by frequency dependent manner. Higher ELF EMFs exposure caused increase of cochlear activity. Ototoxic effect of 10.182 kV/m ELF EMFs may begin at the basal turn of the cochlea by reducing DPOAEs at high frequencies. (C) 2008 Elsevier Ireland Ltd. All rights reserved.Öğe Effects of extremely low frequency electromagnetic fields on transient evoked otoacoustic emissions in rabbits(Elsevier Ireland Ltd, 2009) Budak, Gürer G.; Budak, Bilgehan; Öztürk, Göknur Güler; Muluk, Nuray Bayar; Apan, Alpastan; Seyhan, NesrinObjective: Humans are continuously exposed to an extremely low frequency (ELF) of electromagnetic fields (EMF), transmitted from the common sources like power stations, electric transmission lines, communication and radio-television signal transmission units. The present study aimed to assess the effects of 5.068 kV/m and 10.182 kV/m electric fields, which refer to the lower and upper intensity limits beyond which hazardous effects can be observed, on the auditory functions of rabbits via transient evoked otoacoustic emission (TEOAE) recordings. Methods: The study was performed on 20 healthy adult female New Zealand White rabbits randomly divided into two groups and applied either 5.068 kV/m (Group 1) or 10.182 kV/m (Group 2) of electric field for 3 h/day for 14 days. TEOAE responses were recorded on day 0 before the exposure (0-BE) and on the 6th (6th-AE) and 14th (14th-AE) days after the exposure (AE). Emission amplitudes at 1.0-4.0 kHz were analyzed. Results: In Groups 1 and 2, the amplitudes separately recorded on the 6th-AE day were not different from the amplitudes recorded on day 0-BE. On the 6th-AE day, the only significant difference was detected in the right ear recordings of Group 1 at the frequency of 1.5 kHz (p = 0.007). In Group 1, at 1.5 kHz, the median 6th day AE value (3.8 dB SPL) for the right ear was significantly tower than the median BE value. No significant difference in terms of amplitudes was detected in the comparison of 14th day AE with day 0-BE recordings. In the comparison of the groups for the recordings obtained at all the time points, no statistically significant differences were found. Conclusion: It was concluded that the TEOAE decrease at 1.5 kHz of the right ears of Group I on the 6th day AE was transient; and on the 14th day AE, no significant decrease was determined in the TEOAEs of both groups. Our results showed that the ELF EMFs have no significant effects on the hearing sensation of rabbits, the cochlear functions of whose were evaluated using TEOAE recordings. (C) 2008 Elsevier Ireland Ltd. All rights reserved.Öğe Effects of GSM-like radiofrequency on distortion product otoacoustic emissions in pregnant adult rabbits(Canadian Soc Clinical Investigation, 2009) Budak, Gürer G.; Muluk, Nuray Bayar; Öztürk, Göknur Güler; Budak, Bilgehan; Apan, Alpaslan; Seyhan, Nesrin; Şanlı, CihatObjectives: To determine the effects of 1800 MHz GSM-like Radiofrequency (RFR) on the cochlear functions of pregnant adult rabbits by Distortion Product Otoacoustic Emissions (DPOAEs). Methods: Eighteen 13-month-old pregnant and eighteen 13-month-old non-pregnant New Zealand White rabbits were studied. They were randomly divided into four groups. Nine pregnant rabbits (Group 2) and nine nonpregnant rabbits (Group 4) were exposed to 1800 MHz GSM-like RFR 15 min daily for 7 days. Nine pregnant (Group 1) and nine non-pregnant rabbits (Group 3) were not exposed to GSM like RFR. Cochlear functions were assessed by DPOAEs at 1.0-8.0 kHz. Results: In all pregnant groups except 2.0 kHz, DPOAE amplitudes were not different in Group 2 and Group1. In Group 4, DPOAE amplitudes at 1.0-4.0 kHz (-1.68 dB SPL at 1.0 kHz, 3.05 dB SPL at 1.5 kHz, 2.96 dB SPL at 2.0 kHz, 1.30 dB SPL at 3.0 kHz and 12.22 dB SPL at 4.0 kHz) were lower than Group 3 (8.67 dB SPL at 1.0 kHz, 17.67 dB SPL at 1.5 kHz, 26.10 dB SPL at 2.0 kHz, 18.10 dB SPL at 3.0 kHz and 35.13 dB SPL at 4.0 kHz) (P<0.0125). In the pregnant group, harmful effects of GSM-like RFR were less than in the non-pregnant group. Conclusion: GSM-like RFR caused decreases in DPOAE amplitudes mainly in non-pregnant adult rabbits. Prolonged exposure may affect the DPOAE amplitude. Recommendations are given to prevent the potential hazardous effects of RF in humans.Öğe Effects of GSM-like Radiofrequency on distortion product otoacoustic emissions of rabbits: Comparison of infants versus adults(Elsevier Ireland Ltd, 2009) Budak, Gürer G.; Muluk, Nuray Bayar; Budak, Bilgehan; Öztürk, Göknur Güler; Apan, Alpaslan; Seyhan, Nesrinobjectives: The aim of this study is to investigate the potential hazardous effects of 1800 MHz Global System for Mobile Communications-like (GSM-like) Radiofrequency (RF) exposure on the cochlear functions of female infant and adult rabbits by measuring Distortion Product Otoacoustic Emission (DPOAE) response amplitudes. Methods: Eighteen each one-month-old New Zealand White female rabbits and eighteen each 13-month-old adult rabbits were included into the study. They were randomly divided into four groups. Nine infant rabbits (Group 1) were not exposed to 1800 MHz GSM-like RF (Infant Control, C-In). Nine infant rabbits (Group 2) were exposed to 1800 MHz GSM-like RF, 15 min daily for 7 days after they reached one-month of age (Infant RF, RF-In). Nine adult rabbits were not exposed to 1800 MHz GSM-like RF, 15 min daily for 7 (Adult Control, C-Ad). Nine adult rabbits were exposed to 1800 MHz GSM-like RF, 15 min daily for 7 days (Adult RF, RF-Ad). Cochlear functions were assessed by DPOAEs at 1.0-8.0 kHz. Results: At 1.0-2.0 and 6.0 kHz, the mean DPOAE values of Group 2 were significantly higher than that of Group 1. At 3.0-8.0 kHz, the mean DPOAE values of Group 4 were significantly lower than that of Group 1. At 6.0-8.0 kHz, the mean DPOAE values of Group 2 were significantly higher than that of Group 3. At 1.0-8.0 kHz, the mean DPOAE values of Group 4 were significantly lower than that of Group 2. At 1.08.0 kHz, the mean DPOAE values of Group 4 were significantly lower than that of Group 3. Conclusion: Harmful effects of GSM-like 1800 MHz RF exposure was detected more in the adult female rabbits than infant female rabbits by DPOAE measurement. Prolonged exposure and hyperthermia related to the power density of applied RFR, increasing the temperature in the ear canal, may decrease the DPOAE amplitudes. Water containing medium in the middle ear of infant rabbits may play the protective role **from the RF damage. (C) 2009 Elsevier Ireland Ltd. All rights reserved.Öğe Effects of intrauterine and extrauterine GSM-like radiofrequency on distortion product otoacoustic emissions in infant female rabbits(2009) Budak, Gurer G.; Muluk, Nuray Bayar; Budak, Bilgehan; Ozturk, Goknur Guler; Apan, Alpaslan; Seyhan, NesrinObjective: We investigated the effects of 1,800 MHz GSM-like Radiofrequency (RF) on the cochlear functions of female infant rabbits by Distortion Product Otoacoustic Emission (DPOAE) recordings upon intrauterine (IU) and/or extrauterine (EU) exposure. Materials and Methods: Thirty-six infant female New Zealand White rabbits, each one-month-old, were randomly divided into four groups, Groups 1-4, each having 9 rabbits. Group 1 animals were remained untreated (Control), whereas other groups were treated by virtue of extrauterine (Group 2, EU), intrauterine (Group 3, IU), or both type of exposure (Group 4, IU and EU) to 1800 MHz GSM-like Radiofrequency (RF). EU exposure started after they reached to one-month of age, and IU was at intrauterine period which was in between 15th to 22nd days of gestation. The duration for exposures was 7 days with 15 minutes per day protocol. Cochlear functions were assessed by DPOAEs at 1.0-8.0 kHz. Results: DPOAE amplitudes for EU-RF group at 1.0 and 1.5 kHz was found higher with respect to control. At 2.0 kHz, the recordings for EU-RF group were higher than control and IU-RF groups. At 6.0 kHz, EU-RF group were higher than control, IU-RF, and (IU+EU)-RF groups. At 8.0 kHz, EU-RF group were higher than IU-RF and (IU+EU)-RF groups. Conclusions: We conclude that if the anatomical growth of exposed animate is completed and the extrauterine GSM-like RF exposure is not prolonged, there will not be much harmful effects on inner ear of female rabbits, measured by DPOAEs. The observed increase in DPOAE amplitudes at 1.0-2.0 kHz shows the increase in cochlear activity and outer hair cell electromotility. Prolonged exposure and hyperthermia related to the power density of applied RFR, increasing the temperature in the ear canal, may affect the DPOAE amplitudes especially during intrauterine period. When pregnant women use earphone or even carry their mobile phones in their bags or pockets, foetus may expose to GSM-like RF from the very short distance with the exposure level higher than the standard limits, which may cause ear toxicity with decreased DPOAEs. Copyright 2005 © The Mediterranean Society of Otology and Audiology.Öğe Effects of Intrauterine and Extrauterine GSM-like Radiofrequency on Distortion Product Otoacoustic Emissions in Infant Female Rabbits(Aves, 2009) Budak, Gürer G.; Muluk, Nuray Bayar; Budak, Bilgehan; Öztürk, Göknur Güler; Apan, Alpaslan; Seyhan, NesrinObjective: We investigated the effects of 1,800 MHz GSM-like Radiofrequency (RF) on the cochlear functions of female infant rabbits by Distortion Product Otoacoustic Emission (DPOAE) recordings upon intrauterine (IU) and/or extrauterine (EU) exposure. Materials and Methods: Thirty-six infant female New Zealand White rabbits, each one-month-old, were randomly divided into four groups, Groups 1-4, each having 9 rabbits. Group 1 animals were remained untreated (Control), whereas other groups were treated by virtue of extrauterine (Group 2, EU), intrauterine (Group 3, IU), or both type of exposure (Group 4, IU and EU) to 1800 MHz GSM-like Radiofrequency (RF). EU exposure started after they reached to one-month of age, and IU was at intrauterine period which was in between 15th to 22nd days of gestation. The duration for exposures was 7 days with 15 minutes per day protocol. Cochlear functions were assessed by DPOAEs at 1.0-8.0 kHz. Results: DPOAE amplitudes for EU-RF group at 1.0 and 1.5 kHz was found higher with respect to control. At 2.0 kHz, the recordings for EU-RF group were higher than control and IU-RF groups. At 6.0 kHz, EU-RF group were higher than control, IU-RF, and (IU+EU)-RF groups. At 8.0 kHz, EU-RF group were higher than IU-RF and (IU+EU)-RF groups. Conclusions: We conclude that if the anatomical growth of exposed animate is completed and the extrauterine GSM-like RF exposure is not prolonged, there will not be much harmful effects on inner ear of female rabbits, measured by DPOAEs. The observed increase in DPOAE amplitudes at 1.0-2.0 kHz shows the increase in cochlear activity and outer hair cell electromotility. Prolonged exposure and hyperthermia related to the power density of applied RFR, increasing the temperature in the ear canal, may affect the DPOAE amplitudes especially during intrauterine period. When pregnant women use earphone or even carry their mobile phones in their bags or pockets, foetus may expose to GSM-like RF from the very short distance with the exposure level higher than the standard limits, which may cause ear toxicity with decreased DPOAEs.Öğe Effects of Intrauterine and Extrauterine GSM-like Radiofrequency on Distortion Product Otoacoustic Emissions in Infant Female Rabbits(Aves, 2009) Budak, Gurer G.; Muluk, Nuray Bayar; Budak, Bilgehan; Ozturk, Goknur Guler; Apan, Alpaslan; Seyhan, NesrinObjective: We investigated the effects of 1,800 MHz GSM-like Radiofrequency (RF) on the cochlear functions of female infant rabbits by Distortion Product Otoacoustic Emission (DPOAE) recordings upon intrauterine (IU) and/or extrauterine (EU) exposure. Materials and Methods: Thirty-six infant female New Zealand White rabbits, each one-month-old, were randomly divided into four groups, Groups 1-4, each having 9 rabbits. Group 1 animals were remained untreated (Control), whereas other groups were treated by virtue of extrauterine (Group 2, EU), intrauterine (Group 3, IU), or both type of exposure (Group 4, IU and EU) to 1800 MHz GSM-like Radiofrequency (RF). EU exposure started after they reached to one-month of age, and IU was at intrauterine period which was in between 15th to 22nd days of gestation. The duration for exposures was 7 days with 15 minutes per day protocol. Cochlear functions were assessed by DPOAEs at 1.0-8.0 kHz. Results: DPOAE amplitudes for EU-RF group at 1.0 and 1.5 kHz was found higher with respect to control. At 2.0 kHz, the recordings for EU-RF group were higher than control and IU-RF groups. At 6.0 kHz, EU-RF group were higher than control, IU-RF, and (IU+EU)-RF groups. At 8.0 kHz, EU-RF group were higher than IU-RF and (IU+EU)-RF groups. Conclusions: We conclude that if the anatomical growth of exposed animate is completed and the extrauterine GSM-like RF exposure is not prolonged, there will not be much harmful effects on inner ear of female rabbits, measured by DPOAEs. The observed increase in DPOAE amplitudes at 1.0-2.0 kHz shows the increase in cochlear activity and outer hair cell electromotility. Prolonged exposure and hyperthermia related to the power density of applied RFR, increasing the temperature in the ear canal, may affect the DPOAE amplitudes especially during intrauterine period. When pregnant women use earphone or even carry their mobile phones in their bags or pockets, foetus may expose to GSM-like RF from the very short distance with the exposure level higher than the standard limits, which may cause ear toxicity with decreased DPOAEs.Öğe Pentylenetetrazol-induced seizures are not altered by pre- or post-drug exposure to a 50 Hz magnetic field(Taylor & Francis Ltd, 2007) Canseven, Ayşe G.; Keskil, Zuhal Aktuna; Keskil, Semih; Seyhan, NesrinPurpose: 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. Material and methods: 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. Results: 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. Conclusion: The present study failed to provide any support for a therapeutic potential of a 50 Hz, 0.2 mT MF for epilepsy.
