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1.
Int J Radiat Biol ; 89(12): 1053-60, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23786626

RESUMEN

PURPOSE: To determine whether 50 Hz extremely low frequency-magnetic fields (ELF-MF) affects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes. MATERIALS AND METHODS: Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 µT ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated. RESULTS: There were no significant differences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no difference was observed between the final apoptosis score of the sham and the 100 µT ELF-MF group (p > 0.05), the final apoptosis score was higher in the 500 µT ELF-MF exposure group than in the sham group (p < 0.05). CONCLUSION: Long-term exposure to 100 µT and 500 µT ELF-MF did not affect oxidative or antioxidative processes, lipid peroxidation, or reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 µT ELF-MF did affect active-caspase-3 activity, which is a well-known apoptotic indicator.


Asunto(s)
Apoptosis , Campos Magnéticos , Estrés Oxidativo , Reproducción , Testículo/metabolismo , Animales , Antioxidantes/metabolismo , Caspasa 3/metabolismo , Catalasa/metabolismo , Epidídimo/metabolismo , Inmunohistoquímica , Peroxidación de Lípido , Masculino , Malondialdehído/metabolismo , Oxidantes/metabolismo , Peroxidasa/metabolismo , Ratas , Ratas Sprague-Dawley
2.
Med Sci Monit ; 12(6): BR215-20, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16733479

RESUMEN

BACKGROUND: The aim of this study was to investigate the effect of extremely low frequency magnetic fields (ELFMF) on the uterus and ovary of rats. MATERIAL/METHODS: Forty-eight female Wistar albino rats were divided into two groups, one for 50 and the other for 100 days of exposure. Each group was further divided into two groups, one sham exposed (n=12) and the other the experimental group (n=12). The experimental rats were exposed to 50-Hz 1-mT ELFMF for three hours/day for 50 or 100 days. The sham groups of rats were kept under the same circumstances without applying ELFMF. Electron microscopic examination was performed to evaluate the ovaries and uterus. RESULTS: Ultrastructural dissolution, decrease in cell organelles, cavities in cells, heterochromative appearance, and typical structural loss of the nucleus were observed in germinal epithelial cells of the rat ovaries in the 50-days ELFMF exposure group. Ultrastructural alterations in germinal epithelium and tunica albuginea of ovaries, irregularity in nucleus and nucleolus, increase in lipid vacuoles of cell cytoplasm and reduction in organelles were observed in rat ovaries in the 100-days ELFMF exposure group. Similar alterations were observed in uterus. Malondialdehyde concentration (MDA) of the ovaries and uterus increased in rats of the two exposure groups (p<0.001). CONCLUSIONS: The results of the study showed that 50 and 100 days of exposure to a 1-mT ELFMF can cause alterations at the cellular level and in MDA concentration.


Asunto(s)
Magnetismo , Ovario/efectos de la radiación , Ovario/ultraestructura , Útero/efectos de la radiación , Útero/ultraestructura , Animales , Femenino , Microscopía Electrónica , Ratas , Ratas Wistar
3.
Med Sci Monit ; 12(11): BR366-71, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17072266

RESUMEN

BACKGROUND: Some epidemiological and laboratory studies suggest a possible connection between extremely low-frequency (ELF) magnetic fields and certain illnesses, such as cancer, immune suppression, as well as reproductive toxic effects and abnormalities. Therefore, the aim of this study was to investigate the effects of ELF magnetic fields (1.35 mT) on sperm count, malondialdehyde concentration, the histology of such organs as the testes, brain, liver, and kidney tissues, p53 immunoreactivity of bone marrow, and the serum concentrations of Cu2+, Zn2+, Mn2+, and Fe3+ in rats. MATERIAL/METHODS: Sixteen Sprague-Dawley male rats were divided into two groups. The rats in the experimental group were exposed to an ELF magnetic field 2 hr/day for 2 months (7 days a week). The rats in the control group were not exposed to the ELF magnetic field. The exposure was performed in a Faraday cage (130 x 65 x 80 cm) with grounded shielding against the electric component. The Mann-Whitney U-test was used for the statistical analysis of the data. RESULTS: Magnetic field measurements showed that, under the experimental conditions, the magnetic field-exposure system produced a stable flux density of 1.35+/-0.018 mT and a stable frequency of 50 Hz, with negligible harmonics and no transients. However, no statistically significant alteration was observed in the parameters measured in this study except in Mn2+ concentrations (p<0.001). CONCLUSIONS: The present study found no evidence of an adverse effect of ELF magnetic fields on the measured parameters except for significantly increased Mn2+ concentrations (p<0.001).


Asunto(s)
Campos Electromagnéticos , Regulación de la Expresión Génica , Peroxidación de Lípido/efectos de la radiación , Recuento de Espermatozoides , Proteína p53 Supresora de Tumor/biosíntesis , Animales , Cobre/sangre , Hierro/sangre , Masculino , Malondialdehído/metabolismo , Manganeso/sangre , Ratas , Ratas Sprague-Dawley , Distribución Tisular , Zinc/sangre
4.
J Bone Miner Metab ; 20(6): 345-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12434162

RESUMEN

Osteoporosis is a common health problem, especially in the elderly and in women after menopause. Although there are some treatment methods, they impose serious side effects. Recently, the use of an electromagnetic field (EMF) has been a promising candidate for better treatment of osteoporosis. In the present study, we investigated the preventive effects of low-frequency (50 Hz), low-intensity (1 mT), and long-term (6 weeks) EMF on bone loss in ovariectomized rats. We used 18 female albino Wistar rats (8 unexposed and 10 exposed) to assess the effect of EMF. We examined the mineralization and the morphology of the tibia in control and EMF-exposed rats. The cortical thickness of the tibia was increased in EMF-exposed rats ( P < 0.002). The levels of Na and K in the tibia were significantly increased in rats exposed to EMF ( P < 0.001; P < 0.002, respectively). We also observed an increased blood alkaline phosphatase (ALP) level after EMF exposure ( P < 0.05). No significant differences in the levels of Ca, Mg, Li, or creatine were found between the exposed and unexposed groups. Our data support the notion that an EMF may prove to be an effective treatment method for osteoporosis and other abnormalities related to bone loss.


Asunto(s)
Campos Electromagnéticos , Osteoporosis/prevención & control , Osteoporosis/radioterapia , Fosfatasa Alcalina/sangre , Animales , Densidad Ósea/efectos de la radiación , Calcificación Fisiológica/efectos de la radiación , Femenino , Osteoporosis/patología , Osteoporosis/fisiopatología , Ovariectomía , Ratas , Ratas Wistar , Tibia/patología , Tibia/fisiología , Tibia/efectos de la radiación
5.
Bioelectromagnetics ; 24(3): 182-8, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12669301

RESUMEN

The objective of this study was to investigate the effects of radiofrequency radiation emitted from cellular phones on the lipid composition, malondialdehyde concentration, p53 immune reactivity, sperm count, morphology, histological structure of testes, and on rectal temperature of rats exposed to microwave radiation emitted from cellular phones. Sixteen Spraque-Dawley rats were separated into two groups of eight, sham exposed (control) and experimental. The rats were confined in plexiglas cages specially designed for this study, and cellular phones were placed 0.5 cm under the cages. For the experimental group, cellular phones were activated 20 min per day (7 days a week) for 1 month. For the control group, the cellular phones were placed beneath the cages for 20 min a day, but the phones were turned off. Rectal temperatures were measured weekly. For 250 mW radiated power, the whole body average SAR (rms) is 0.52 W/kg and 1 g averaged peak SAR (rms) is 3.13 W/kg. The Mann-Whitney U-test was used for statistical comparisons of groups. No statistically significant alteration in any of the endpoints was noted. This study found no evidence suggesting an adverse effect of cell phone exposure on measures of testicular function or structure.


Asunto(s)
Teléfono Celular/instrumentación , Microondas , Testículo/fisiología , Testículo/efectos de la radiación , Irradiación Corporal Total , Animales , Temperatura Corporal/efectos de la radiación , Teléfono Celular/clasificación , Relación Dosis-Respuesta en la Radiación , Masculino , Malondialdehído/análisis , Malondialdehído/metabolismo , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Recuento de Espermatozoides , Espermatozoides/citología , Espermatozoides/efectos de la radiación , Testículo/citología , Proteína p53 Supresora de Tumor/inmunología
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