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1.
Indian J Exp Biol ; 52(9): 890-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25241589

RESUMO

Reports of declining male fertility have renewed interest in assessing the role of electromagnetic fields (EMFs). Testicular function is particularly susceptible to the radiation emitted by EMFs. Significant decrease in sperm count, increase in the lipid peroxidation damage in sperm cells, reduction in seminiferous tubules and testicular weight and DNA damage were observed following exposure to EMF in male albino rats. The results suggest that mobile phone exposure adversely affects male fertility.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Espermatozoides/efeitos da radiação , Testículo/efeitos da radiação , Animais , Ensaio Cometa , Masculino , Tamanho do Órgão/efeitos da radiação , Ratos , Ratos Wistar , Contagem de Espermatozoides
2.
Int J Radiat Biol ; 89(3): 147-54, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23078358

RESUMO

UNLABELLED: Abstract Purpose: Reports of declining male fertility have renewed interest in the role of environmental and occupational exposures in the etiology of human infertility. The aim of the present work was to investigate the effect of 10 GHz exposure on the male Wistar rat's reproductive system and to find out the possible causative factors. MATERIALS AND METHODS: The study was divided into sham-exposed and exposed groups. Seventy day-old rats were exposed to 10 GHz microwave radiation for 2 h per day for 45 days at power density 0.21 mW/cm(2) and specific absorption rate (SAR) of 0.014 W/kg. After the end of the experiment, blood samples were collected for the estimation of in vivo chromosomal aberration damage and micronucleus test. Spermatozoa were taken out for estimation of Caspase-3, comet assay, testosterone and electron microscopy and compared with sham-exposed. RESULTS: The study of scanning electron microscopic revealed shrinkage of the lumen of the seminiferous tubules. Apoptotic bodies were found in exposed group. A flow cytometry examination showed formation of micronuclei body in lymphocytes of exposed group. Comet assay confirmed DNA (deoxyribonucleic acid) strand break. Testosterone level was found significantly decreased with the shrinkage of testicular size. CONCLUSIONS: 10 GHz field has an injurious effect on fertility potential of male-exposed animals.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Infertilidade Masculina/etiologia , Animais , Caspase 3/metabolismo , Aberrações Cromossômicas , Ensaio Cometa , Quebras de DNA , Modelos Animais de Doenças , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Masculino , Testes para Micronúcleos , Tamanho do Órgão , Ratos , Ratos Wistar , Túbulos Seminíferos/patologia , Estresse Fisiológico , Testículo/metabolismo , Testículo/patologia , Testosterona/sangue
3.
Indian J Exp Biol ; 51(12): 1079-85, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24579373

RESUMO

A specific absorption rate (SAR) measurements system has been developed for compliance testing of personal mobile phone in a brain phantom material contained in a Perspex box. The volume of the box has been chosen corresponding to the volume of a small rat and illuminated by a 3G mobile phone frequency (1718.5 MHz), and the emitted radiation directed toward brain phantom .The induced fields in the phantom material are measured. Set up to lift the plane carrying the mobile phone is run by a pulley whose motion is controlled by a stepper motor. The platform is made to move at a pre-determined rate of 2 degrees per min limited up to 20 degrees. The measured data for induced fields in various locations are used to compute corresponding SAR values and inter comparison obtained. These data are also compared with those when the mobile phone is placed horizontally with respect to the position of the animal. The SAR data is also experimentally obtained by measuring a rise in temperature due to this mobile exposures and data compared with those obtained in the previous set. To seek a comparison with the safety criteria same set of measurements are performed in 10 g phantom material contained in a cubical box. These results are higher than those obtained with the knowledge of induced field measurements. It is concluded that SAR values are sensitive to the angular position of the moving platform and are well below the safety criteria prescribed for human exposure. The data are suggestive of having a fresh look to understand the mode of electromagnetic field -bio interaction.


Assuntos
Encéfalo/efeitos da radiação , Telefone Celular , Radiometria , Absorção , Animais , Campos Eletromagnéticos , Humanos , Imagens de Fantasmas , Ratos
5.
Electromagn Biol Med ; 31(3): 195-203, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22897400

RESUMO

The specific absorption rate (SAR) measurements are carried out for compliance testing of personal 3G Mobile phone. The accuracy of this experimental setup has been checked by comparing the SAR in 10 gm of simulated tissue and an arbitrary shaped box. This has been carried out using a 3G mobile Phone at 1718.5 MHz, in a medium simulating brain and muscle phantom. The SAR measurement system consists of a stepper motor to move a monopole E-field probe in two dimensions inside an arbitrary shaped box. The phantom is filled with appropriate frequency-specific fluids with measured electrical properties (dielectric constant and conductivity). That is close to the average for gray and white matters of the brain at the frequencies of interest (1718.5 MHz). Induced fields are measured using a specially designed monopole probe in its close vicinity. The probe is immersed in the phantom material. The measured data for induced fields are used to compute SAR values at various locations with respect to the mobile phone location. It is concluded that these SAR values are position dependent and well below the safety criteria prescribed for human exposure.


Assuntos
Telefone Celular , Imagens de Fantasmas , Radiometria/instrumentação , Absorção/efeitos da radiação , Encéfalo/efeitos da radiação , Eletricidade , Humanos , Músculos/efeitos da radiação , Ondas de Rádio/efeitos adversos , Irradiação Corporal Total
6.
Electromagn Biol Med ; 31(3): 223-32, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22897403

RESUMO

Reports of declining male fertility have renewed interest in assessing the role of environmental and occupational exposures to electromagnetic fields (EMFs) in the aetiology of human infertility. Testicular functions are particularly susceptible to electromagnetic fields. The aim of the present work was to investigate the effect of 10-GHz EMF on male albino rat's reproductive system and to investigate the possible causative factor for such effect of exposure. The study was carried out in two groups of 70-day old adult male albino rats: a sham-exposed and a 10-GHz-exposed group (2 h a day for 45 days). Immediately after completion of the exposure, animals were sacrificed and sperms were extracted from the cauda and caput part of testis for the analysis of MDA, melatonin, and creatine kinase. Creatine kinase results revealed an increased level of phosphorylation that converts creatine to creatine phosphate in sperms after EMF exposure. EMF exposure also reduced the level of melatonin and MDA. It is concluded that microwave exposure could adversely affect male fertility by reducing availability of the above parameters. These results are indications of deleterious effects of these radiations on reproductive pattern of male rats.


Assuntos
Infertilidade Masculina/etiologia , Micro-Ondas/efeitos adversos , Animais , Contagem de Células Sanguíneas , Creatina Quinase/metabolismo , Infertilidade Masculina/sangue , Infertilidade Masculina/metabolismo , Infertilidade Masculina/fisiopatologia , Masculino , Malondialdeído/metabolismo , Melatonina/sangue , Estresse Oxidativo/efeitos da radiação , Ratos , Ratos Wistar , Reprodução/efeitos da radiação , Espermatozoides/enzimologia , Espermatozoides/metabolismo , Espermatozoides/efeitos da radiação
7.
Electromagn Biol Med ; 31(3): 233-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22897404

RESUMO

The present study deals with the effects of chronic exposure of low-level microwave radiation on developing rat brain. Starting at 35 days of age, male rats were exposed to 2 h/day for another 35 days to a 16.5-GHz microwave radiation field. After the exposure period, the rats were sacrificed, and brain tissues dissected out and used for biochemical assay. Results showed that exposure to a 16.5-GHz radiation caused significant changes in the activity of protein kinase C as compared to the control group. Furthermore, electron microscopic study revealed an increase in glial cell population. These results confirm that brain cell membrane is an interactive site for electromagnetic field causing an inflammation and possibly tumor promotion.


Assuntos
Encéfalo/enzimologia , Encéfalo/efeitos da radiação , Micro-Ondas/efeitos adversos , Animais , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Relação Dose-Resposta à Radiação , Imageamento por Ressonância Magnética , Masculino , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar
8.
Cell Biochem Biophys ; 63(1): 97-102, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22426826

RESUMO

Present study concerns with various biochemical changes in the developing rat brain exposed to 9.9 GHz (square wave modulated, 1 kHz) at power density 0.125 mW/cm(2) (specific absorption rate 1.0 W/kg) for 2 h/day for 35 days. Thirty days old male wistar rats were used for this present study. Each group consists of eight animals. After the exposure, biochemical assays such as calcium ion efflux, calcium-dependent protein kinase (PKC), and ornithine decarboxylase (ODC) were performed on the brain tissue. Results of this study reveal that chronic exposure of rat to microwave radiation alter the activity of certain enzymes. There was a significant increase in calcium ion efflux and the activity of ODC. On the other hand, there is a significant decrease in PKC activity. Since these enzymes are related to growth, any alteration may lead to affect functioning of the brain and its development.


Assuntos
Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Micro-Ondas , Animais , Encéfalo/enzimologia , Cálcio/metabolismo , Masculino , Ornitina Descarboxilase/metabolismo , Proteínas Quinases/metabolismo , Ratos , Ratos Wistar
10.
Toxicol Mech Methods ; 21(1): 13-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21080782

RESUMO

This study aims to suggest the limits of silver nanoparticle (AgNP) uses for medicinal purpose and was performed to explore the effect of various doses of silver nanoparticle in rats. Four different doses of AgNP (4, 10, 20, and 40 mg/kg) were injected intravenously. For safety evaluation of injected AgNP, body weight, organ coefficient, whole blood count, and biochemistry panel assay for liver function enzyme (AST, ALT, ALP, and GGTP), comet assay, ROS, and histological parameter were performed; 10-12 week old animals were randomly divided into groups of six individuals each for control, and doses of 40, 20, 10, and 4 mg/kg AgNP injected. Significant changes were observed (p < 0.01) in hematological parameters (WBC count, platelets counts, haemoglobin, and RBC count) in the 40 and 20 mg/kg groups. The changes were non-significant in the other groups (4 and 10 mg/kg group). In the 40 mg/kg group, a significant increase was also found in liver function enzymes like ALT and AST (p < 0.01), ALP (p < 0.01), GGTP (p < 0.01), and bilirubin (p < 0.01). ROS in blood serum increased in the high dose group. Tail migration in single cell gel electrophoresis in the 40, 20, 10, 4 mg/kg, and control groups was 34.9, 29.5, 17.8, 5.8, and 0.0 µm, respectively, which indicated damage in the DNA strand in the high dose group. EDXRF showed a ∼ 10-times increase in silver concentration in the 40 mg/kg group and TEM image also showed particle deposition in the 40 mg/kg group. This study indicates that the AgNP in doses (< 10 mg/kg) is safe for biomedical application and has no side-effects, but its high dose (> 20 mg/kg) is toxic.


Assuntos
Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Rim/efeitos dos fármacos , Rim/ultraestrutura , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio , Prata/administração & dosagem , Prata/química , Baço/efeitos dos fármacos
11.
Mol Cell Biochem ; 348(1-2): 191-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21086023

RESUMO

This study concerns with the multiple treatment of the target site to potent carcinogen and the super imposition of low level radiofrequency and microwave radiation. Swiss albino mice (male) were used for this investigation. The study has been divided in two parts, part A: a single dose of 7,12-dimethylbenz(a)anthracene (DMBA) 100 µg/animal was applied topically on the skin of mice and were exposed to 112 MHz amplitude modulated (AM) at 16 Hz (power density 1.0 mW/cm(2), specific absorption rate (SAR) 0.75 W/kg). Similarly after a single dose of DMBA, mice were exposed to 2.45 GHz radiation (power density of 0.34 mW/cm(2), SAR, 0.1 W/kg), 2 h/day, 3 days a week for a period of 16 weeks. The two sets of experiments were carried out separately. Part B: mice were transplanted intraperitoneally (ip) with ascites 8 × 10(8) (Ehrlich-Lettre ascites, strain E) carcinoma cells per mouse. These mice were exposed to 112 MHz amplitude modulated at 16 Hz and 2.45 GHz radiation separately for a period of 14 days. There was no tumor development in mice exposed to RF and MW. Similarly a topical application of single dose of DMBA followed by RF/MW exposure also did not produce any visible extra tumor on the skin of mice. On the other hand mice were transplanted intraperitoneally with ascites (8 × 10(8) cell/ml) and subsequently exposed to above mentioned fields for 14 days showed a slight increase in the cell numbers as compared to the control group. However, the increase is insignificant. There were insignificant differences either in the mortality or cell proliferation among the control and exposed group. This results show that low level RF or MW do not alter tumor growth and development as evidenced by no observable change in tumor size.


Assuntos
Carcinoma de Ehrlich/etiologia , Micro-Ondas , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Cutâneas/etiologia , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinoma de Ehrlich/patologia , Proliferação de Células/efeitos da radiação , Hiperplasia , Masculino , Camundongos , Neoplasias Induzidas por Radiação/patologia , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia , Fatores de Tempo , Carga Tumoral/efeitos da radiação
12.
Int J Radiat Biol ; 86(4): 334-43, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20353343

RESUMO

PURPOSE: To investigate the effect of 2.45 GHz microwave radiation on rat brain of male wistar strain. MATERIAL AND METHODS: Male rats of wistar strain (35 days old with 130 +/- 10 g body weight) were selected for this study. Animals were divided into two groups: Sham exposed and experimental. Animals were exposed for 2 h a day for 35 days to 2.45 GHz frequency at 0.34 mW/cm(2) power density. The whole body specific absorption rate (SAR) was estimated to be 0.11 W/Kg. Exposure took place in a ventilated Plexiglas cage and kept in anechoic chamber in a far field configuration from the horn antenna. After the completion of exposure period, rats were sacrificed and the whole brain tissue was dissected and used for study of double strand DNA (Deoxyribonucleic acid) breaks by micro gel electrophoresis and the statistical analysis was carried out using comet assay (IV-2 version software). Thereafter, antioxidant enzymes and histone kinase estimation was also performed. RESULTS: A significant increase was observed in comet head (P < 0.002), tail length (P < 0.0002) and in tail movement (P < 0.0001) in exposed brain cells. An analysis of antioxidant enzymes glutathione peroxidase (P < 0.005), and superoxide dismutase (P < 0.006) showed a decrease while an increase in catalase (P < 0.006) was observed. A significant decrease (P < 0.023) in histone kinase was also recorded in the exposed group as compared to the control (sham-exposed) ones. One-way analysis of variance (ANOVA) method was adopted for statistical analysis. CONCLUSION: The study concludes that the chronic exposure to these radiations may cause significant damage to brain, which may be an indication of possible tumour promotion (Behari and Paulraj 2007).


Assuntos
Antioxidantes/efeitos da radiação , Encéfalo/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Micro-Ondas , Animais , Antioxidantes/metabolismo , Encéfalo/enzimologia , Encéfalo/metabolismo , Encéfalo/patologia , Catalase/metabolismo , Catalase/efeitos da radiação , Ensaio Cometa , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/efeitos da radiação , Masculino , Protamina Quinase/metabolismo , Protamina Quinase/efeitos da radiação , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Superóxido Dismutase/efeitos da radiação , Fatores de Tempo
13.
Int J Nanomedicine ; 4: 133-44, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19774112

RESUMO

The purpose of the present study was to use capacitive coupling of pulsed electromagnetic field (CC-PEMF) and hydroxyapatite nanoparticles (HAp) as a countermeasure to prevent osteoporosis induced by simulated microgravity. We used the hind-limb suspension (HLS) rat model to simulate microgravity-induced bone losses for 45 days. In order to compare the resulting changes, mineralogical (bone mineral density [BMD], calcium [Ca], and phosphorus [P]), biochemical (osteocalcin, alkaline phosphatase [ALP], and type I collagen), and histological (scanning electron microscopy) parameters were adopted. As a countermeasure to the above, the effect of PEMF and HAp application were examined. Three-month-old female Wistar rats were randomly divided into control (n = 8), HLS (n = 8), HLS with PEMF (n = 8), HLS with HAp nanoparticles (n = 8), and HLS with HAp and PEMF (n = 8). We observed: 1) significant decrease (p < 0.01) in BMD, Ca, P, type I collagen, and ALP activity in femur and tibia in hind-limb bone and serum osteocalcin in HLS rats as compared with the ground control. 2) Nonsignificant increase in BMD (p < 0.1), Ca (p < 0.1), P (p < 0.5), type I collagen (p < 0.1), and ALP activity (p < 0.5) in femur and tibia in hind-limb bone and serum osteocalcin (p < 0.5) in HLS + PEMF rats compared with HLS rats. 3) Significant increase in BMD (p < 0.02), Ca (p < 0.05), P (p < 0.05), type I collagen (p < 0.02), and ALP activity (p > 0.02) in femur and tibia in hind-limb bone with a nonsignificant increase in serum osteocalcin (p > 0.1) in HLS + HAp rats compared to HLS rats. 4) Significant increase in BMD (p > 0.01). Ca (p > 0.01). P (p > 0.01). type I collagen (p > 0.01). and ALP activity (p > 0.01) in femur and tibia in hind-limb bone and serum osteocalcin (p > 0.02) were also observed. Results suggest that a combination of low level PEMF and Hap nanoparticles has potential to control bone loss induced by simulated microgravity.


Assuntos
Durapatita/uso terapêutico , Magnetoterapia/métodos , Nanopartículas/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteogênese/efeitos da radiação , Osteólise/etiologia , Osteólise/prevenção & controle , Simulação de Ausência de Peso/efeitos adversos , Animais , Terapia Combinada/métodos , Campos Eletromagnéticos , Feminino , Elevação dos Membros Posteriores/efeitos adversos , Nanomedicina/métodos , Osteólise/patologia , Ratos , Ratos Wistar , Resultado do Tratamento
14.
Int J Cosmet Sci ; 31(3): 177-82, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19302510

RESUMO

Kajal and surma are eye cosmetics extensively used in Indian subcontinent. Kajal is prepared by burning of vegetable oil and butter oil while surma by grinding of the stones. High performance liquid chromatography and gas chromatography-mass spectrometry instruments were used for quantification and confirmation of 16 polyaromatic hydrocarbons (PAHs). Significant concentration of PAH was found in all the samples examined. The median concentration of PAH ranged from 0.14 (lowest, anthracene) to 31.18 microg g(-1) [dibenz(a,h)anthracene] in kajal sample and from not detectable concentration (naphthalene) to 197.47 microg g(-1) of benzo(a)pyrene in surma sample. Fifteen PAHs were detected in all the samples. Therefore the use of kajal and surma in eye should be strictly restricted.


Assuntos
Cosméticos/química , Compostos Policíclicos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Índia , Espectrofotometria Ultravioleta
15.
Appl Biochem Biotechnol ; 158(1): 126-39, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19089649

RESUMO

The object of this study is to investigate the effects of 50-GHz microwave radiation on the brain of Wistar rats. Male rats of the Wistar strain were used in the study. Animals of 60-day age were divided into two groups-group 1, sham-exposed, and group 2, experimental (microwave-exposed). The rats were housed in a temperature-controlled room (25 degrees C) with constant humidity (40-50%) and received food and water ad libitum. During exposure, rats were placed in Plexiglas cages with drilled ventilation holes and kept in an anechoic chamber. The animals were exposed for 2 h a day for 45 days continuously at a power level of 0.86 microW/cm(2) with nominal specific absorption rate 8.0 x 10(-4) w/kg. After the exposure period, the rats were killed and homogenized, and protein kinase C (PKC), DNA double-strand break, and antioxidant enzyme activity [superoxides dismutase (SOD), catalase, and glutathione peroxidase (GPx)] were estimated in the whole brain. Result shows that the chronic exposure to these radiations causes DNA double-strand break (head and tail length, intensity and tail migration) and a significant decrease in GPx and SOD activity (p = or<0.05) in brain cells, whereas catalase activity shows significant increase in the exposed group of brain samples as compared with control (p = or<0.001). In addition to these, PKC decreased significantly in whole brain and hippocampus (p < 0.05). All data are expressed as mean +/- standard deviation. We conclude that these radiations can have a significant effect on the whole brain.


Assuntos
Encéfalo/efeitos da radiação , Micro-Ondas/efeitos adversos , Animais , Antioxidantes/metabolismo , Encéfalo/citologia , Encéfalo/enzimologia , Encéfalo/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Masculino , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar
16.
Bull Environ Contam Toxicol ; 79(3): 306-10, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17639317

RESUMO

Effect of selenium pretreatment (0.2 mg/kg/day, as sodium selenite), 4 h prior to mercury treatment (0.4 mg/kg/day, as mercuric chloride), administered intraperitoneally, was examined after daily exposure for 20 days' in rats. Liver, kidney and brain tissues were assayed for malondialdehyde (MDA) level, glutathione (GSH) content and mercury concentration. Mercury induced MDA levels, which was also observed in selenium pretreated animals. Significant reduction in GSH levels was observed in mercury alone and selenium pretreated animals. Mercury accumulation was in the order of kidney, liver and brain. Selenium pretreatment resulted in further enhancement in mercury accumulation in liver and kidney.


Assuntos
Encéfalo/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Mercúrio/toxicidade , Selênio/farmacologia , Animais , Encéfalo/metabolismo , Glutationa/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Mercúrio/farmacocinética , Ratos
18.
Indian J Exp Biol ; 45(1): 77-85, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17249331

RESUMO

The present article delineates the epidemiological and experimental studies of electromagnetic field which affects various tissues of human body. These affects lead to cell proliferation, which may lead to cancer formation. Certain biomarkers have been identified which are one way or the other responsible for tumor promotion or co-promotion. These are (i) melatonin, a hormone secreted by pineal gland, (ii) Ca2+, which is essential in the regulation of the resting membrane potential and in the sequence of events in synaptic excitation and neurotransmitter, release are affected by electromagnetic field, (iii) ornithine decarboxylase (ODC), a rate-limiting enzyme in the biosynthesis of polyamines, considered as a useful biological marker; over expression of ODC can cause cell transformation and enhancement of tumor promotion. (iv) protein kinase is an enzyme, which transfers phosphate groups from ATP to hydroxyl groups in the amino acid chains of acceptor proteins, and (v) Na+-K+ ATPase, which transports sodium and potassium ions across the membrane has a critical role in living cells. The various possible mechanisms depending upon non equilibrium thermodynamics, co-operativism, stochastic and resonance are discussed as possible models of signal transduction in cytosol, thereby controlling the transcription phenomena. Finally a mechanism comprising the extremely low frequency and radio frequency (RF)/microwave (MW) modulated field is compared.


Assuntos
Biomarcadores Tumorais/análise , Campos Eletromagnéticos/efeitos adversos , Neoplasias Induzidas por Radiação/diagnóstico , Animais , DNA/efeitos da radiação , Quebras de DNA , Humanos , Micro-Ondas/efeitos adversos , Ondas de Rádio/efeitos adversos
19.
Clin Chim Acta ; 377(1-2): 92-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17027950

RESUMO

BACKGROUND: The effects of lead on the hematological system results in the inhibition of heme synthesis and in anemia. Lead may affect the absorption and metabolism of essential trace metals also. There is little information especially from the northern region of India regarding the relationship between blood lead levels>or=10 microg/dl and anemia in children. We performed a cross-sectional study to evaluate the association of blood lead levels>or=10 microg/dl with anemia, and its effect on hematological system and some essential trace metals in children. METHODS: A total of 75 children aged 1-7 years, 50 anemic (Hb8 g%), drawn from Lucknow, India and nearby areas were recruited to determine blood levels of lead, iron, zinc, copper, and calcium along with hematological parameters [delta-aminolevulinic acid dehydratase (delta-ALAD) hemoglobin (Hb), hematocrit, and ascorbic acid]. RESULTS: Based on Centre for Disease Control and Prevention's intervention level of blood lead, children were categorized into those with blood lead<10 microg/dl (6.89+/-2.44) (n=19) (GI) and those with blood lead<10 microg/dl (21.86+/-7.58) (n=56) (GII). After adjustment for child's age, sex, and area of residence, children with blood lead levels>or=10 microg/dl were 2.87 (95% CI: 1.60-2.87) times as likely to have anemia as children with blood lead levels<10 microg/dl. The differences of the adjusted mean values of Hb, delta-ALAD, and hematocrit were significantly lower in children from the GII group when compared to children from the GI group (p<0.01, p<0.01, and p<0.05, respectively). Among essential trace metals, adjusted mean levels of blood iron, zinc, and calcium were significantly lower in GII as compared to GI (P<0.05 each). There were significant negative correlations of blood lead levels with delta-ALAD (r=-0.612, p<0.01), hematocrit (r=-0.427, p<0.05), iron (r=-0.552, p<0.05) zinc (r=-0.427, p<0.05), and calcium (r=-0.324, p<0.05). CONCLUSION: Results indicate that elevated blood lead levels (>or=10 microg/dl) in children were significantly associated with risk of anemia and that blood lead levels also influenced the status of essential trace metals. However, results of this study may be limited due to limited sample size but certainly form the basis of a larger sample size study, taking into account all the known potential confounders of anemia in children.


Assuntos
Anemia/sangue , Cálcio/sangue , Cobre/sangue , Ferro/sangue , Chumbo/sangue , Zinco/sangue , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino
20.
Electromagn Biol Med ; 25(1): 61-70, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16595335

RESUMO

There is growing concern by the public regarding the potential human health hazard due to exposure to microwave frequencies. 2.45 GHz radiation widespread use in industry, research, and medicine, and leakage into the environment is possible. In order to quantitate this, experiments were performed on developing rat brain. Male Wistar 35-day-old rats (n = 6) were used for this study. Animals were exposed to 2.45 GHz radiation for 2 h/day for a period of 35 days at a power density of 0.344 mW/cm(2) (SAR 0.11 W/kg). The control group was sham irradiated. After 35 days these rats were sacrificed and whole brain tissue was isolated for protein kinase C (PKC) assay. For morphological study the forebrain was isolated from the whole brain and PKC activity was measured using P(32) labeled ATP. Our study reveals a statistically significant (p < 0.05) decrease in PKC activity in hippocampus as compared to the remaining portion of the whole brain and the control group. A similar experiment conducted on hippocampus and the whole brain gave a similar result. Electron microscopic study shows an increase in the glial cell population in the exposed group as compared to the control group. This present study is indicative of a significant change after exposure to the above-mentioned field intensity. This suggests that chronic exposures may affect brain growth and development.


Assuntos
Encéfalo/efeitos da radiação , Micro-Ondas/efeitos adversos , Neuroglia/efeitos da radiação , Proteína Quinase C/efeitos da radiação , Ondas de Rádio/efeitos adversos , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Masculino , Microscopia Eletrônica , Neuroglia/metabolismo , Proteína Quinase C/metabolismo , Doses de Radiação , Ratos , Ratos Wistar
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