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1.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769173

RESUMO

In the human environment, the increasing exposure to radiofrequency (RF) radiation, especially that emitted by wireless devices, could be absorbed in the body. Recently, mobile and emerging wireless technologies (UMTS, DECT, LTE, and Wi-Fi) have been using higher frequencies than 2G GSM systems (900/1800 MHz), which means that most of the circulating RF currents are absorbed into the skin and the superficial soft tissue. The harmful genotoxic, cytotoxic, and mutagenic effects of solar ultraviolet (UV) radiation on the skin are well-known. This study aimed at investigating whether 2422 MHz (Wi-Fi) RF exposure combined with UV radiation in different sequences has any effect on the inflammation process in the skin. In vitro experiments examined the inflammation process by cytokines (IL-1α, IL-6, IL-8) and MMP-1 enzyme secretion in a 3D full-thickness human skin model. In the first study, UV exposure was immediately followed by RF exposure to measure the potential additive effects, while in the second study, the possible protective phenomenon (i.e., adaptive response) was investigated when adaptive RF exposure was challenged by UV radiation. Our results suggest that 2422 MHz Wi-Fi exposure slightly, not significantly increased cytokine concentrations of the prior UV exposure. We could not detect the adaptive response phenomenon.


Assuntos
Inflamação , Ondas de Rádio , Humanos , Ondas de Rádio/efeitos adversos , Raios Ultravioleta/efeitos adversos , Pele , Citocinas
2.
Artigo em Inglês | MEDLINE | ID: mdl-32575398

RESUMO

The absorption of exposure to radiofrequency (RF) emitted by wireless devices leads to a high specific absorption rate in the skin. Ultraviolet (UV) radiation can induce several damages to the skin. The aim of this study was to examine whether combined, consecutive exposure to solar UV radiation and 1950 MHz RF exposure of third generation (3G) mobile system have any effect on inflammation processes in the skin. Under in vitro experiments, the inflammation process was examined by cytokines (IL-1α, IL-6, and IL-8) and MMP-1 enzyme secretion on 3D full thickness human skin model. The RF exposure was applied before or after UV irradiation, in order to study either the possible cooperative or protective effects of exposure to RF and UV. We did not find changes in cytokines due to exposure to RF alone. The RF exposure did not enhance the effects of UV radiation. There was a statistically not-significant decrease in cytokines when the skin tissues were pre-exposed to RF before being exposed to 4 standard erythemal dose (SED) UV compared to UV exposure alone. We found that RF exposure reduced the previously UV-treated MMP-1 enzyme concentration. This study might support the evaluation of the effects on the skin exposed to microwave radiation of 5G mobile technology.


Assuntos
Telefone Celular , Inflamação , Ondas de Rádio , Raios Ultravioleta , Citocinas/metabolismo , Humanos , Modelos Biológicos , Ondas de Rádio/efeitos adversos , Pele , Raios Ultravioleta/efeitos adversos
3.
Artigo em Inglês | MEDLINE | ID: mdl-31561904

RESUMO

The widespread presence of electromagnetic sources in daily life has initiated several studies on the effects of radiofrequency and power frequency fields. Only few investigations on the genotoxic effects of exposure to intermediate frequency magnetic fields (IF-MF) have been done so far. Therefore, the aim of this study was to evaluate possible genotoxic effects of exposure to 123.90 kHz and 250.80 kHz IF-MF on canine and human blood. Blood was exposed to IF-MF at 630 A/m (0.79 mT) and 80 A/m (0.10 m T) with exposure durations of 1-5 h (hourly), 20 and 24 h. Cylindrically divided Petri dish system was developed for in vitro exposures where different induced current could be achieved in the samples at the same magnetic flux density level. For the assessment of genotoxicity the alkaline comet assay was applied. We detected a statistically significant increase in DNA damage only following 20 h exposure to IF-MF.


Assuntos
Ensaio Cometa , Dano ao DNA , Leucócitos/efeitos da radiação , Campos Magnéticos/efeitos adversos , Adulto , Animais , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , DNA/sangue , DNA/efeitos da radiação , Cães , Relação Dose-Resposta à Radiação , Campos Eletromagnéticos , Desenho de Equipamento , Feminino , Humanos , Leucócitos/química , Magnetismo/instrumentação , Masculino , Pessoa de Meia-Idade
4.
Int J Radiat Biol ; 89(10): 870-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23679232

RESUMO

PURPOSE: This study focuses on the effects of high-field (3T) magnetic resonance imaging (MRI) scans on the DNA integrity of human leukocytes in vitro in order to validate the study where genotoxic effects were obtained and published by Lee et al. MATERIALS AND METHODS: The scanning protocol and exposure situation were the same as those used under routine clinical brain MRI scan. Peripheral blood samples from healthy non-smoking male donors were exposed to electromagnetic fields (EMF) produced by 3T magnetic resonance imaging equipment for 0, 22, 45, 67, and 89 min during the scanning procedure. Samples of positive control were exposed to ionizing radiation (4 Gy of (60)Co-γ). Single breaks of DNA in leukocytes were detected by single-cell gel electrophoresis (Comet assay). Chromosome breakage, chromosome loss and micronuclei formations were detected by a micronucleus test (MN). Three independent experiments were performed. RESULTS: The data of comet tail DNA%, olive tail moment and micronucleus frequency showed no DNA damages due to MRI exposure. CONCLUSIONS: The results of the Comet assay and the micronucleus test indicate that the applied exposure of MRI does not appear to produce breaks in the DNA and has no significant effect on DNA integrity.


Assuntos
DNA/genética , Leucócitos/metabolismo , Leucócitos/efeitos da radiação , Imageamento por Ressonância Magnética/efeitos adversos , Adulto , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Quebras de DNA de Cadeia Simples/efeitos da radiação , Raios gama/efeitos adversos , Humanos , Masculino , Testes para Micronúcleos
5.
Bioelectromagnetics ; 31(6): 488-94, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20564169

RESUMO

The aim of this study was to reveal whether static magnetic fields (SMFs) influence the repair of radiation-damaged DNA on leukocytes or has any effect on DNA. After 4 Gy of (60)Co-gamma irradiation, some of the samples were exposed to inhomogeneous SMFs with a lateral magnetic flux density gradient of 47.7, 1.2, or 0.3 T/m by 10 mm lateral periodicity, while other samples were exposed to homogeneous SMF of 159.2 +/- 13.4 mT magnetic flux density for a time period of 0.5 min, 1, 2, 4, 6, 18, 20, or 24 h. Another set of samples was exposed to the aforementioned SMFs before gamma irradiation. The following three groups were examined: (i) exposed to SMF only, (ii) exposed to SMF following irradiation by (60)Co-gamma, and (iii) exposed to SMF before (60)Co-gamma irradiation. The analysis of the DNA damage was made by single-cell gel electrophoresis technique (comet assay). Statistically significant differences were found at 1 h (iSMF), 4 h (hSMF), and 18 h (hSMF) if samples were exposed to only SMF, compared to control. When the SMF exposure followed the (60)Co-gamma irradiation, statistically significant differences were found at 1 h (iSMF) and 4 h (hSMF). If exposure to SMF preceded (60)Co-gamma irradiation, no statistically significant difference was found compared to 4 Gy gamma-irradiated group.


Assuntos
Reparo do DNA/efeitos da radiação , DNA/genética , Raios gama , Magnetismo , Adulto , Dano ao DNA , Humanos , Leucócitos/metabolismo , Leucócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
6.
Radiat Res ; 172(2): 244-51, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19630529

RESUMO

Abstract The European project EMFnEAR was undertaken to assess potential changes in human auditory function after a short-term exposure to radiofrequency (RF) radiation produced by UMTS (Universal Mobile Telecommunication System) mobile phones. Participants were healthy young adults with no hearing or ear disorders. Auditory function was assessed immediately before and after exposure to radiofrequency radiation, and only the exposed ear was tested. Tests for the assessment of auditory function were hearing threshold level (HTL), distortion product otoacoustic emissions (DPOAE), contralateral suppression of transiently evoked otoacoustic emission (CAS effect on TEOAE), and auditory evoked potentials (AEP). The exposure consisted of speech at a typical conversational level delivered via an earphone to one ear, plus genuine or sham RF-radiation exposure produced by a commercial phone controlled by a personal computer. Results from 134 participants did not show any consistent pattern of effects on the auditory system after a 20-min UMTS exposure at the maximum output of the phone with 69 mW/kg SAR in the cochlea region in a double blind comparison of genuine and sham exposure. An isolated effect on the hearing threshold at high frequencies was identified, but this was statistically nonsignificant after correction for multiple comparisons. It is concluded that UMTS short-term exposure at the maximum output of consumer mobile phones does not cause measurable immediate effects on the human auditory system.


Assuntos
Percepção Auditiva/fisiologia , Percepção Auditiva/efeitos da radiação , Telefone Celular , Exposição Ambiental , Audição/fisiologia , Audição/efeitos da radiação , Adolescente , Adulto , Campos Eletromagnéticos , Europa (Continente) , Feminino , Testes Auditivos , Humanos , Masculino , Doses de Radiação , Adulto Jovem
7.
BMC Public Health ; 7: 325, 2007 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-17997856

RESUMO

BACKGROUND: There are about 1.6 billion GSM cellular phones in use throughout the world today. Numerous papers have reported various biological effects in humans exposed to electromagnetic fields emitted by mobile phones. The aim of the present study was to advance our understanding of potential adverse effects of the GSM mobile phones on the human hearing system. METHODS: Auditory Brainstem Response (ABR) was recorded with three non-polarizing Ag-AgCl scalp electrodes in thirty young and healthy volunteers (age 18-26 years) with normal hearing. ABR data were collected before, and immediately after a 10 minute exposure to 900 MHz pulsed electromagnetic field (EMF) emitted by a commercial Nokia 6310 mobile phone. Fifteen subjects were exposed to genuine EMF and fifteen to sham EMF in a double blind and counterbalanced order. Possible effects of irradiation was analyzed by comparing the latency of ABR waves I, III and V before and after genuine/sham EMF exposure. RESULTS: Paired sample t-test was conducted for statistical analysis. Results revealed no significant differences in the latency of ABR waves I, III and V before and after 10 minutes of genuine/sham EMF exposure. CONCLUSION: The present results suggest that, in our experimental conditions, a single 10 minute exposure of 900 MHz EMF emitted by a commercial mobile phone does not produce measurable immediate effects in the latency of auditory brainstem waves I, III and V.


Assuntos
Telefone Celular/estatística & dados numéricos , Campos Eletromagnéticos/efeitos adversos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos da radiação , Adolescente , Adulto , Comércio/instrumentação , Método Duplo-Cego , Feminino , Humanos , Masculino , Ondas de Rádio/efeitos adversos , Ondas de Rádio/classificação , Fatores de Tempo
8.
Reprod Toxicol ; 22(1): 111-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16434166

RESUMO

The aim of our study was to evaluate the possible effects of whole-body 1800 MHz GSM-like microwave exposure on male reproduction. After repeated exposure of mice to microwaves at 0.018-0.023 W/kg whole-body specific energy absorption rate (SAR) an elevated serum testosterone level was measured, but no microwave exposure related histopathological alteration could be detected in the reproductive organs. The in vitro steroidogenic response of 48 h Leydig cell cultures obtained from exposed animals did not differ from the controls, suggesting that Leydig cells were not the primary targets of the applied microwave exposure or direct action of microwaves on Leydig cells was temporary only. In exposed animals the red blood cell count and volume of packed red cells were also increased. Further investigations are required to clarify the mechanism of action of the applied microwave exposure on male mice, as well as to establish the biological significance of the observed phenomena.


Assuntos
Micro-Ondas/efeitos adversos , Hormônios Testiculares/biossíntese , Testículo/efeitos da radiação , Irradiação Corporal Total/métodos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal/efeitos da radiação , Células Cultivadas , Colesterol/sangue , Contagem de Eritrócitos , Técnicas In Vitro , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos , Doses de Radiação , Testículo/metabolismo , Testosterona/biossíntese , Triglicerídeos/sangue
9.
Magy Onkol ; 49(2): 149-51, 2005.
Artigo em Húngaro | MEDLINE | ID: mdl-16249811

RESUMO

The aim of this study was to evaluate the possible effects of in vivo 1800 MHz GSM-like exposure on male reproduction. In five separate experiments, male NMRI mice (35-41 g) were exposed (11-12 mice each) to 1800 MHz GSM-like radiation. The average power density was 100 microW/cm2, the estimated SAR was 0.018-0.023 W/kg. The animals were exposed ten times (over two weeks on workdays) and the duration of exposure was 2 h/day. On the day of the last treatment, mice were anesthetized with i.p. pentobarbital, and blood samples were taken for hematology, serum chemistry and serum testosterone (T) determinations (ELISA). Testicles, epididymes, adrenals, prostates and pituitary glands were removed for histology. One testicle of each animal was used for culture of Leydig cells. The cells were cultured for 48 h in the presence or absence of human chorionic gonadotropin (hCG) to evaluate the in vitro steroidogenic response of Leydig cells. In the exposed animals red blood cell count (RBC: 8.59+/-0.10 T/l, n=37) and volume of packed red cells (VPRC: 42.29+/-0.43%, n=37) were significantly higher (p<0.01) compared with the controls (RBC: 8.12+/-0.08 T/l, n=36; VPRC: 39.76+/-0.36%, n=36). The serum testosterone level of the exposed animals (7.85+/-1.08 ng/ml, n=56) was also significantly elevated (p<0.05) compared to the controls (5.12+/-0.79, n=52), while the in vitro steroidogenic capacity of the Leydig cells was unaltered. No significant differences in the other investigated variables were found between controls and exposed mice. Our results indicate that the applied GSM-like microwave exposure may induce slight, but statistically significant alterations in some hematological and endocrine parameters of male mice within the physiological range. Further investigations are required to establish the biological significance of these phenomena.


Assuntos
Biomarcadores/sangue , Campos Eletromagnéticos/efeitos adversos , Gônadas/efeitos da radiação , Micro-Ondas/efeitos adversos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Colesterol/sangue , Relação Dose-Resposta à Radiação , Contagem de Eritrócitos , Hematócrito , Hemoglobinas/metabolismo , Contagem de Leucócitos , Masculino , Camundongos , Contagem de Plaquetas , Doses de Radiação , Triglicerídeos/sangue
10.
ScientificWorldJournal ; 4 Suppl 2: 83-90, 2004 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-15517106

RESUMO

The main goal of this study was to evaluate the possible effect of whole-body magnetic field (MF) exposure on the steroidogenic capacity of Leydig cells in vitro. In four separate experiments, male CFLP mice were exposed to sinusoidal 50-Hz, 100-microT MF. The duration of exposure was 23.5 h/day over a period of 14 days. At the end of the exposure, interstitial (Leydig) cells were isolated from the testicles of the sham-exposed and exposed animals. The cells were cultured for 48 h in the presence or absence of 1, 10, or 100 mIU/ml human chorionic gonadotropin (hCG). The luteinizing hormone (LH) analog hCG was used to check the testosterone (T) response of the sham-exposed controls and to evaluate the possible effect of the whole-body MF exposure on the steroidogenic capacity of Leydig cells in vitro. Testosterone content of the culture media and blood sera was measured by radioimmunoassay (RIA). In the cultures obtained from MF-exposed animals, the hCG-stimulated T response was significantly higher (p < 0.01) compared with the sham-exposed controls, while the basal T production of cells and the level of serum T remained unaltered. No MF exposure-related histopathological alterations were found in testicles, epididymes, adrenals, prostates, and pituitary glands. The MF exposure did not affect the animal growth rate and the observed hematologic and serum chemical variables. Our results indicate a presumably direct effect of whole-body MF exposure on the hCG-stimulated steroidogenic response of mouse Leydig cells.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Células Intersticiais do Testículo/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Glândulas Suprarrenais/fisiologia , Glândulas Suprarrenais/efeitos da radiação , Animais , Peso Corporal/efeitos da radiação , Células Cultivadas , Epididimo/patologia , Epididimo/efeitos da radiação , Humanos , Células Intersticiais do Testículo/química , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Hipófise/patologia , Hipófise/efeitos da radiação , Próstata/patologia , Próstata/efeitos da radiação , Doses de Radiação , Lesões Experimentais por Radiação/sangue , Radiação não Ionizante/efeitos adversos , Testículo/patologia , Testículo/efeitos da radiação , Testosterona/biossíntese , Testosterona/sangue , Irradiação Corporal Total/métodos
11.
Bioelectromagnetics ; 24(8): 531-4, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14603472

RESUMO

In this study, the effect of exposure to 900 and 1800 MHz GSM-like radiofrequency radiation upon the urinary 6-sulfatoxymelatonin (6SM) excretion of adult male Wistar rats was studied. Seventy-two rats were used in six independent experiments, three of which were done with 900 MHz and the other three with 1800 MHz. The exposures were performed in a gigahertz transverse electromagnetic mode (GTEM) cell. The power densities of radiation were 100 and 20 microW/cm(2) at 900 and 1800 MHz frequency, respectively. The carrier frequency was modulated with 218 Hz, as in the GSM signal. The animals were exposed for 2 h between 8:00 AM and noon daily during the 14 day exposure period. The urine of rats was collected from 12:00 AM to 8:00 AM, collecting from exposed and control animal groups on alternate days. The urinary 6SM concentration was measured by (125)I radioimmunoassay and was referred to creatinine. The combined results of three experiments done with the same frequency were statistically analyzed. Statistically significant changes in the 6SM excretion of exposed rats (n = 18) compared to control group (n = 18) were not found either at 900 or 1800 MHz.


Assuntos
Telefone Celular , Relação Dose-Resposta à Radiação , Melatonina/análogos & derivados , Melatonina/urina , Micro-Ondas , Glândula Pineal/metabolismo , Glândula Pineal/efeitos da radiação , Radiometria/métodos , Animais , Masculino , Melatonina/metabolismo , Doses de Radiação , Ratos , Ratos Wistar , Irradiação Corporal Total
12.
Aviat Space Environ Med ; 74(5): 506-11, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12751577

RESUMO

INTRODUCTION: In spite of the known importance of cerebral blood flow (CBF) monitoring for aviation, spaceflight, military and emergency medicine, and neurosurgical intra- and postoperative monitoring, there is no standard noninvasive technique for continuous CBF monitoring. One potential method for this purpose is the electrical impedance technique, called rheoencephalography (REG). The development of improved electronics and computation tools has done much to overcome the difficulties of REG measurement. REG technology now has possibilities for application to the fields mentioned above. HYPOTHESIS: Our hypothesis was that REG would reflect CBF changes. METHODS: Three experimental studies were undertaken to further define in vivo (rat, pig) CBF measurements by analysis of REG pulse waves. CO2 inhalation (4-20%), brain electrical stimulation, and aorta compression (5 min) were the applied CBF manipulations. In the case of aorta compression, global CBF was measured by REG, and local CBF by the laser Doppler method. Data were digitized and processed off-line. RESULTS: During CO2 inhalation and electrical stimulation of the brain, REG amplitude increased, indicating increased cerebral fluid volume. A linear relationship was established between CO2 concentration and REG peak amplitude (correlation coefficient: 0.88, p = 0.05), and the ascending portion of the curve (0.88, p = 0.05). During aorta compression, systemic arterial pressure increased (p = 0.008), and REG amplitude decreased (-23.75%, p = 0.01). CONCLUSION: These studies have confirmed the REG amplitude changes during known CBF manipulations. The difference between local and global CBF response demonstrated CBF autoregulation and heterogeneity. Together, these studies indicate the usefulness and potential benefit of computerized REG monitoring for the above-mentioned fields.


Assuntos
Circulação Cerebrovascular , Eletroencefalografia/métodos , Animais , Dióxido de Carbono/metabolismo , Impedância Elétrica , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Suínos
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