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1.
Electromagn Biol Med ; 32(4): 471-83, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23656297

RESUMO

Spinal cord injury (SCI) is unequivocally reported to produce hyperalgesia to phasic stimuli, while both hyper- and hypoalgesia to tonic stimuli. The former is spinally mediated and the latter centrally. Besides, its management is unsatisfactory. We report the effect of magnetic field (MF; 17.96 µT, 50 Hz) on tonic pain behavior and related neurotransmitters in the brain of complete thoracic (T13) SCI rats at week 8. Adult male Wistar rats were divided into Sham, SCI and SCI+MF groups. Formalin-pain behavior was compared utilizing 5 min block pain rating (PR), 60 min session-PR, time spent in various categories of increasing pain (T0-T3) and flinch incidences. Serotonin (5-HT), dopamine (DA), norepinepherine (NE), gamma-aminobutyric acid (GABA), glutamate and glycine were estimated in brain tissue by liquid chromatography-mass spectrometry. Session-PR, block-PR and number of flinches were significantly lower, while time spent in categories 0-1 was higher in the SCI versus Sham group. These parameters were comparable in the SCI+MF versus Sham group. 5-HT concentration in cortex, remaining forebrain areas and brain stem (BS), was lower while GABA and NE were higher in BS of SCI, which were comparable with Sham in the SCI+MF group. The concentration of DA, glutamate and glycine was comparable amongst the groups. The data indicate significant hypoalgesia in formalin pain while increased in GABA, NE and decreased in 5-HT post-SCI, which were restored in the SCI+MF group. We suggest beneficial effect of chronic (2 h/day × 8 weeks) exposure to MF (50 Hz, 17.96 µT) on tonic pain that is mediated by 5-HT, GABA and NE in complete SCI rats.


Assuntos
Encéfalo/metabolismo , Magnetoterapia , Neurotransmissores/metabolismo , Manejo da Dor , Dor/etiologia , Dor/metabolismo , Traumatismos da Medula Espinal/complicações , Animais , Comportamento Animal , Locomoção , Masculino , Dor/patologia , Dor/fisiopatologia , Ratos , Ratos Wistar , Medula Espinal/patologia
2.
Clinics (Sao Paulo) ; 66(7): 1237-45, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21876981

RESUMO

INTRODUCTION: Environmental exposure to man-made electromagnetic fields has been steadily increasing with the growing demand for electronic items that are operational at various frequencies. Testicular function is particularly susceptible to radiation emitted by electromagnetic fields. OBJECTIVES: This study aimed to examine the therapeutic effects of a pulsed electromagnetic field (100 Hz) on the reproductive systems of male Wistar rats (70 days old). METHODS: The experiments were divided into five groups: microwave sham, microwave exposure (2.45 GHz), pulsed electromagnetic field sham, pulsed electromagnetic field (100 Hz) exposure, and microwave/pulsed electromagnetic field exposure. The animals were exposed for 2 hours/day for 60 days. After exposure, the animals were sacrificed, their sperm was used for creatine and caspase assays, and their serum was used for melatonin and testosterone assays. RESULTS: The results showed significant increases in caspase and creatine kinase and significant decreases in testosterone and melatonin in the exposed groups. This finding emphasizes that reactive oxygen species (a potential inducer of cancer) are the primary cause of DNA damage. However, pulsed electromagnetic field exposure relieves the effect of microwave exposure by inducing Faraday currents. CONCLUSIONS: Electromagnetic fields are recognized as hazards that affect testicular function by generating reactive oxygen species and reduce the bioavailability of androgen to maturing spermatozoa. Thus, microwave exposure adversely affects male fertility, whereas pulsed electromagnetic field therapy is a non-invasive, simple technique that can be used as a scavenger agent to combat oxidative stress.


Assuntos
Magnetoterapia/efeitos adversos , Micro-Ondas/efeitos adversos , Testículo/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Biomarcadores/análise , Caspase 3/análise , Creatina Quinase/análise , Infertilidade Masculina/etiologia , Masculino , Melatonina/análise , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Testosterona/análise , Fatores de Tempo
3.
Clinics ; 66(7): 1237-1245, 2011. ilus
Artigo em Inglês | LILACS | ID: lil-596915

RESUMO

INTRODUCTION: Environmental exposure to man-made electromagnetic fields has been steadily increasing with the growing demand for electronic items that are operational at various frequencies. Testicular function is particularly susceptible to radiation emitted by electromagnetic fields. OBJECTIVES: This study aimed to examine the therapeutic effects of a pulsed electromagnetic field (100 Hz) on the reproductive systems of male Wistar rats (70 days old). METHODS: The experiments were divided into five groups: microwave sham, microwave exposure (2.45 GHz), pulsed electromagnetic field sham, pulsed electromagnetic field (100 Hz) exposure, and microwave/pulsed electromagnetic field exposure. The animals were exposed for 2 hours/day for 60 days. After exposure, the animals were sacrificed, their sperm was used for creatine and caspase assays, and their serum was used for melatonin and testosterone assays. RESULTS: The results showed significant increases in caspase and creatine kinase and significant decreases in testosterone and melatonin in the exposed groups. This finding emphasizes that reactive oxygen species (a potential inducer of cancer) are the primary cause of DNA damage. However, pulsed electromagnetic field exposure relieves the effect of microwave exposure by inducing Faraday currents. CONCLUSIONS: Electromagnetic fields are recognized as hazards that affect testicular function by generating reactive oxygen species and reduce the bioavailability of androgen to maturing spermatozoa. Thus, microwave exposure adversely affects male fertility, whereas pulsed electromagnetic field therapy is a non-invasive, simple technique that can be used as a scavenger agent to combat oxidative stress.


Assuntos
Animais , Masculino , Ratos , Magnetoterapia/efeitos adversos , Micro-Ondas/efeitos adversos , Testículo/efeitos da radiação , Apoptose/efeitos da radiação , Biomarcadores/análise , /análise , Creatina Quinase/análise , Infertilidade Masculina/etiologia , Melatonina/análise , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Fatores de Tempo , Testosterona/análise
4.
J Biomed Mater Res B Appl Biomater ; 92(1): 189-95, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19810112

RESUMO

Mineral content, mineral composition, and crystalline pattern of bone in osteoporosis are different from those of normal individuals. Present management of bone mineral loss is rather unsatisfactory primarily because of socioeconomic factors and untoward effects of the treatment drugs. We report the efficacy of capacitive-coupled pulsed electric field (CCPEF) to prevent bone loss in an ovariectomized rat model of osteoporosis. One month postsurgery either leg was stimulated with CCPEF, whereas the other leg did not receive any stimulation (sham exposed). The treatment was given in 60 sessions each of 2 h/d (5 days a week). The control group of rats was sham operated. At the end of the observation period, femur and tibia bones were removed. Their bone mineral content (BMC), calcium, phosphorus, and carbon contents were analyzed and bone mineral density (BMD) was calculated. The BMC data were supported by X-ray diffraction (XRD) method. In sham-exposed bones, a statistically significant decrease in BMC, BMD, calcium, and phosphorus contents were obtained as compared to the control. Although in CCPEF bones, there was an attenuation of decrement in the noted parameters except phosphorus. XRD pattern supported these observations. The results suggest that chronic, 60 sessions of 2 h/d, 5 d/wk CCPEF (14 MHz with 16 Hz modulation 16 Hz and 10 V peak to peak) is effective in attenuating the ovariectomy-induced bone mineral loss in rats.


Assuntos
Densidade Óssea , Estimulação Elétrica , Ovariectomia , Suporte de Carga , Animais , Osso e Ossos/química , Cálcio/química , Carbono/análise , Feminino , Fósforo/análise , Ratos , Ratos Wistar , Difração de Raios X
5.
Indian J Exp Biol ; 48(10): 982-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21299040

RESUMO

Chronic (2 h/d x 8 weeks) exposure to magnetic field (MF; 50 Hz, 17.9 microT) in complete spinal cord (T13) transected rats restored food intake (FI), water intake (WI) and body weight (BW) which were decreased in the spinal cord injured rats. The results suggest a significant beneficial effect of chronic exposure to magnetic field of paraplegic rats.


Assuntos
Magnetoterapia , Traumatismos da Medula Espinal/terapia , Animais , Peso Corporal , Ingestão de Líquidos , Ingestão de Alimentos , Masculino , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Tempo
6.
Indian J Exp Biol ; 48(10): 1008-19, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21299044

RESUMO

The scientific basis of nanotechnology as envisaged from the first principles is compared to bulk behavior. Development of nanoparticles having controllable physical and electronic properties has opened up possibility of designing artificial solids. Top down and bottom up approaches are emphasized. The role of nanoparticle (quantum dots) application in nanophotonics (photovoltaic cell), and drug delivery vehicle is discussed. Fundamentals of DNA structure as the prime site in bionanotechnological manipulations is also discussed. A summary of presently available devices and applications are presented.


Assuntos
Nanotecnologia , Animais , DNA/química , Durapatita/uso terapêutico , Magnetoterapia , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanopartículas/toxicidade , Nanotubos de Carbono/química , Fenômenos Ópticos , Osteoporose/terapia , Pontos Quânticos , Ratos , Eliminação de Resíduos Líquidos
7.
Indian J Med Res ; 130(6): 720-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20090133

RESUMO

BACKGROUND & OBJECTIVE: Postmenopausal osteoporosis leads to a significant decline in bone mass. That complicates the treatment outcome. The objective of the present study was to find out the effects of pulsed modulated low level electric field capacitively coupled on bone histology of induced osteoporotic rats, for screening the potential therapy for osteoporosis. METHODS: Osteopororosis was induced by performed by bilateral ovariectomy of female Wistar rats. After one month of surgery electric field stimulation was delivered to one leg of experimatal rats while the other was sham exposed. After 60 days of exposure treated rats were sacrificed and femur and tibia bones were segregated into (i) control (CON), (ii) ovariectomized (OVX) and (iii) ovariectomized + electrical stimulation (OVX+ES). RESULTS: Histopathological analyses showed that capacitively coupled pulsed electric field exposure treatment augmented and restored the bone marrow cell population. Immunohistological localization of alkaline phosphatase (ALP) showed the increased activity of this enzyme after electrostimulation, which showed an enhanced osteoblast differentiation. Collagen histochemistry showed high amount of collagen fiber in exposed rats bones than that of osteoporotic bones. Electron microscopic study revealed the enhancement of microstructural composition and compactness in cortical and trabecular part of treated bones. INTERPRETATION & CONCLUSION: Our results suggest that capacitively coupled pulsed electric field exposure treatment of specified parameters is efficacious in attenuating the effects of ovariectomy induced osteoporosis and restore the bone loss.


Assuntos
Osso e Ossos/patologia , Terapia por Estimulação Elétrica/métodos , Osteoporose/patologia , Osteoporose/terapia , Fosfatase Alcalina/metabolismo , Animais , Células da Medula Óssea/patologia , Osso e Ossos/metabolismo , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Osteoporose/metabolismo , Ovariectomia , Ratos , Ratos Wistar
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