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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.
Acta Crystallogr C Struct Chem ; 73(Pt 8): 632-637, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28776515

RESUMO

Phosphine-phosphoramidites (PPAs) are heterobidentate ligands that have been developed in the last two decades and have been used successfully in asymmetric catalytic reactions. A single crystal of the PPA (11bS)-N-[(2S,4S)-4-(diphenylphosphanyl)pentan-2-yl]-N-methyldinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepin-4-amine, C38H35NO2P2, was prepared and structurally characterized by single-crystal X-ray diffraction and density functional theory (DFT) calculations. Structure elucidation revealed unique features which might have a significant effect in the excellent chemical stability of this type of molecule. The conformation of the molecule provides an optimal chelating structure. Iridium complexes of UPPhos were found to be efficient catalysts in the asymmetric hydrogenation of imines {UPPhos is (11bS)-N-[(2S,4S)-4-(diphenylphosphanyl)pentan-2-yl]-N-(propan-2-yl)dinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepin-4-amine}.

5.
Artigo em Inglês | MEDLINE | ID: mdl-27598182

RESUMO

We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Monitoramento de Radiação , Campos Eletromagnéticos/efeitos adversos , Eletrônica/instrumentação , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Europa (Continente)/epidemiologia , Guias como Assunto , Utensílios Domésticos , Humanos , Centrais Elétricas , Radiometria , Medição de Risco
6.
Int J Occup Med Environ Health ; 27(6): 1036-42, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25519943

RESUMO

OBJECTIVES: Nowadays more and more newly introduced light sources (tungsten-halogen, compact fluorescent (CFL) and light-emitting diode (LED) lamps) are used in households. It is important to know whether their radiation poses any possible risk for human health or not. These light sources emit optical radiation not solely in the visible spectrum. Other bands emitted by these sources, i.e., ultraviolet and infrared, are potentially hazardous for human health. The visible light, especially the blue light, could also damage human retina. The purpose of this study was to determine the ultraviolet (UV) and blue light (BL) emissions from halogen bulbs, CFLs and LED lamps, and to evaluate them from the point of view of possible health risks for general public. MATERIAL AND METHODS: The exposure of UV and BL emissions from 19 types of CFLs, 11 types of halogen lamps and 4 types of LED lamps produced by different manufacturers were measured at 200 mm distance from the source. RESULTS: The exposures to UV and BL were below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) exposure limits in spite of the very conservative assumption of the assessment. CONCLUSIONS: Results of this study indicate that the UV and BL radiation from the newly introduced lamps does not exceed the current exposure limit values and thus, in comparison with the former incandescent bulbs, does not result in a higher risk for general public.


Assuntos
Exposição Ambiental/análise , Utensílios Domésticos , Iluminação/instrumentação , Raios Ultravioleta , Cor , Fluorescência , Halogênios , Humanos , Iluminação/efeitos adversos , Fotobiologia , Radiometria , Medição de Risco
7.
Lasers Surg Med ; 46(8): 644-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24909318

RESUMO

BACKGROUND AND OBJECTIVE: Low level laser therapy (LLLT) has been developed for non-invasive treatment of joint diseases. We have previously shown that LLLT influenced synovial protein expression in rheumatoid arthritis (RA). The aim of this study was to assess the effects of laser irradiation on osteoarthritic (OA) synovial protein expression. STUDY DESIGN/MATERIALS AND METHODS: The synovial membrane samples removed from the knees of 6 OA patients were irradiated ex vivo using near infrared diode laser (807-811 nm; 25 J/cm(2) ). An untreated sample taken from the same patient served as control. Synovial protein separation and identification were performed by two-dimensional differential gel electrophoresis and mass spectrometry, respectively. RESULTS: Eleven proteins showing altered expression due to laser irradiation were identified. There were three patients whose tissue samples demonstrated a significant increase (P < 0.05) in mitochondrial heat shock 60 kD protein 1 variant 1. The expression of the other proteins (calpain small subunit 1, tubulin alpha-1C and beta 2, vimentin variant 3, annexin A1, annexin A5, cofilin 1, transgelin, and collagen type VI alpha 2 chain precursor) significantly decreased (P < 0.05) compared to the control samples. CONCLUSIONS: A single diode laser irradiation of the synovial samples of patients with osteoarthritis can statistically significantly alter the expression of some proteins in vitro. These findings provide some more evidence for biological efficacy of LLLT treatment, used for osteoarthritis.


Assuntos
Citosol/química , Terapia com Luz de Baixa Intensidade/métodos , Osteoartrite do Joelho/terapia , Proteínas/metabolismo , Membrana Sinovial/química , Idoso , Eletroforese em Gel Bidimensional , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
8.
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
9.
Dalton Trans ; 41(31): 9493-502, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22760339

RESUMO

A series of new phosphine-phosphite ligands P(C)(n)OP (n = 1-4) have been synthesized and used for rhodium-catalyzed asymmetric hydrogenation of prochiral olefins in order to study the effect of the chelate ring size. Excellent ees (up to 97.5%) were obtained in the hydrogenation of dimethyl itaconate and an increase of activity and enantioselectivity was observed in the hydrogenation of (Z)-α-acetamidocinnamic acid methyl ester with the increasing length of the backbone of the ligands.

10.
Prog Biophys Mol Biol ; 107(3): 449-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21986474

RESUMO

Personal RF exposimetry has been in the focus of the bioelectromagnetics community in the last few years. With a few exceptions, exposimetry studies focused on adults, because measuring the exposure of children, one of the most important target groups, introduces many complications. The main feature of our study is to select teachers and kindergarten caretakers as volunteers. They are expected to receive similar exposure patterns as the children because they spend the workday close to them. Thus they can stand as proxies for estimation of exposures of children. Volunteers belonging to one of two groups (elementary school teachers, n=31; employees of kindergartens and day nurseries, n=50) in Hungarian cities received a Personal Exposimeter (PEM) for 24h each. Only workdays, when the volunteers worked near children, were considered. 51 additional volunteers (office workers) were measured as controls. The volunteers wore the PEMs on their bodies. Those activities marked in the exposure diaries as work were further classified into 5 categories based on the level of certainty that they actually worked near children during that activity. Subsets of the full dataset were derived and compared based on this categorization. It was found that relaxation of the selection criteria often under- or overestimates exposure. The differences of estimation depend on the frequency band and sub-population: the kindergarten and teacher groups differ in this regard. For most frequency bands the majority of data points was below the detection limit. Derived child exposures are comparable to the worktime exposure of adults (control group).


Assuntos
Creches/estatística & dados numéricos , Exposição Ocupacional/análise , Ondas de Rádio , Instituições Acadêmicas/estatística & dados numéricos , Adulto , Criança , Pré-Escolar , Estudos de Viabilidade , Humanos , Lactente , Ondas de Rádio/efeitos adversos , Radiometria , Telecomunicações/instrumentação
11.
Phys Ther ; 91(5): 665-74, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21436364

RESUMO

BACKGROUND: Soft-laser therapy has been used to treat rheumatic diseases for decades. The major effects of laser treatment may be dependent not on thermal mechanisms but rather on cellular, photochemical mechanisms. However, the exact cellular and molecular mechanisms of action have not been elucidated. OBJECTIVE: The aim of this study was to investigate the ex vivo effects of low-level laser treatment (with physical parameters similar to those applied previously) on protein expression in the synovial membrane in rheumatoid arthritis (RA). DESIGN: Synovial tissues were laser irradiated, and protein expression was analyzed. METHODS: Synovial membrane samples obtained from 5 people who had RA and were undergoing knee surgery were irradiated with a near-infrared diode laser at a dose of 25 J/cm(2) (a dose used in clinical practice). Untreated synovial membrane samples obtained from the same people served as controls. Synovial protein expression was assessed with 2-dimensional polyacrylamide gel electrophoresis followed by mass spectrometry. RESULTS: The expression of 12 proteins after laser irradiation was different from that in untreated controls. Laser treatment resulted in the decreased expression of α-enolase in 2 samples and of vimentin and precursors of haptoglobin and complement component 3 in 4 samples. The expression of other proteins, including 70-kDa heat shock protein, 96-kDa heat shock protein, lumican, osteoglycin, and ferritin, increased after laser therapy. LIMITATIONS: The relatively small sample size was a limitation of the study. CONCLUSIONS: Laser irradiation (with physical parameters similar to those used previously) resulted in decreases in both α-enolase and vimentin expression in the synovial membrane in RA. Both proteins have been considered to be important autoantigens that are readily citrullinated and drive autoimmunity in RA. Other proteins that are expressed differently also may be implicated in the pathogenesis of RA. Our results raise the possibility that low-level laser treatment of joints affected with RA may be effective, at least in part, by suppressing the expression of autoantigens. Further studies are needed.


Assuntos
Artrite Reumatoide/metabolismo , Artrite Reumatoide/cirurgia , Autoantígenos/metabolismo , Terapia com Luz de Baixa Intensidade/métodos , Fosfopiruvato Hidratase/metabolismo , Membrana Sinovial/metabolismo , Vimentina/metabolismo , Adulto , Idoso , Análise de Variância , Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Estudos de Casos e Controles , Proteoglicanas de Sulfatos de Condroitina/imunologia , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Feminino , Ferritinas/imunologia , Ferritinas/metabolismo , Proteínas de Choque Térmico/imunologia , Proteínas de Choque Térmico/metabolismo , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Sulfato de Queratano/imunologia , Sulfato de Queratano/metabolismo , Lumicana , Espectrometria de Massas , Pessoa de Meia-Idade , Fosfopiruvato Hidratase/imunologia , Membrana Sinovial/imunologia , Vimentina/imunologia
12.
Radiat Prot Dosimetry ; 142(2-4): 354-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20924120

RESUMO

Starting in 2009, certain types of incandescent light bulbs will be withdrawn from the market in the European Union and elsewhere. However, compact fluorescent lamps that are among the candidates to replace them produce intermediate frequency electric fields (EFs) much higher than any other device or appliance previously available to the general public. Measurement results of these EFs showed that the maximum recorded EF strength in the 1.2-100 kHz frequency range in close proximity to the lamps was > 42 V m(-1) for all tested lamps. In nine cases, the field strength exceeded 87 V m(-1) and the highest measured value was 216 V m(-1).


Assuntos
Campos Eletromagnéticos , Exposição Ambiental , Iluminação/instrumentação , Eletricidade , Habitação , Humanos
13.
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
14.
Dalton Trans ; (33): 6528-35, 2009 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-19672498

RESUMO

New stereodynamic diphosphinites derived from 2,2'-biphosphole, were synthesised by introduction of a linker obtained from chiral diols between the two phosphorus atoms and used for catalytic hydrogenation through a dual chirality control induced by Rh-coordination. The application of these ligands in hydrogenation of dimethyl itaconate shows that the enantioselectivity strongly depends on steric and electronic properties of the chiral linker whereas the sense of enantioselection is determined by the configuration of these stereocentres. These stereodynamic diphosphinites induce higher enantioselectivities than the analogous stereodynamic diphosphanes derived from 2,2-biphosphole.

15.
Radiat Prot Dosimetry ; 131(4): 469-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18667401

RESUMO

Exposure to 50 Hz magnetic field (MF) was evaluated in 31 multi-level apartment buildings with built-in step-down transformer stations. In each building, three apartments were selected: one apartment located immediately above the transformer room (index apartment), one located on the same floor and one on a higher floor. The mean value of measured MFs was 0.98 microT in apartments above transformers, 0.13 microT on the same floor, and 0.1 microT in on higher floors. The mean measured MF value was higher than 0.2 microT in 30 (97%) index apartments, 4 (14%) on the same floor as the index apartments and 4 (13%) on higher floors. The corresponding numbers were 25 (81%), 0 and 0, respectively, when 0.4 microT was used as cut-point. It is concluded that apartments in building with built-in transformers can be reliably classified into high and low-exposure categories based on their location in relation to transformers.


Assuntos
Eletricidade , Campos Eletromagnéticos , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Habitação , Doses de Radiação , Monitoramento de Radiação/métodos , Hungria
16.
Orv Hetil ; 148(7): 319-25, 2007 Feb 18.
Artigo em Húngaro | MEDLINE | ID: mdl-17344152

RESUMO

INTRODUCTION: The vitamin D3 formation in skin is the most important natural source of vitamin D demands of humans. The key step of the phototransformation of provitamin D into previtamin D from which the vitamin D3 is formed by thermal conversion. According to studies run at the latitudes of Hungary the UV-B radiation in winter time is not satisfactory to ensure the need of the vitamin D, which can result in vitamin D 3 deficiency and increases risk of osteoporosis. AIMS: The aim of this study was to verify whether in the Hungarian population the UV radiation from the Sun ensures the daily synthesis of 1000 IU vitamin D3, or Vitamin D deficiency could occur in the winter and spring months which are less favourable in terms of UV exposure. METHODS: The data of UV-B radiation reaching the Earth's surface were used for the evaluation. These data based on regular measurements in Budapest. According to the average of UV-B radiation of each months the "best case scenario" of vitamin D3 production was estimated by using the most optimal conditions of vitamin D synthesis. RESULTS: It was calculated, that the effective UV irradiance reaching the Earth's surface at noon in Budapest is the highest in July, while the lowest is in December. The difference between these two months is more than 35-fold for July. In the period between November and March more than 200 minutes have to be spent outdoor to ensure the production of satisfactory amount of vitamin D in skin. On one hand, it is irrealistically long time because it exceeds the duration of maximum irradiation around noon which was the basis of our calculation. On the other hand, if only the face and hands are uncovered then the required radiant exposure exceeds the 1 minimal erythemal dose, i.e. the skin would be burnt. CONCLUSIONS: Based on our calculations it was found, that in Budapest more than 95% of yearly effective UV-B radiation is measurable in the period between March and October. Therefore it can be assumed that the UV-B radiation would not be sufficient in the period between November and February, even if its efficacy would not be limited by clothing and less time spent outdoor which are anyway characteristic and necessary in that part of the year.


Assuntos
Estações do Ano , Luz Solar , Raios Ultravioleta , Deficiência de Vitamina D/prevenção & controle , Vitamina D/biossíntese , Vitamina D/efeitos da radiação , Vestuário , Humanos , Hungria , Queimadura Solar , Protetores Solares/administração & dosagem , Fatores de Tempo , Deficiência de Vitamina D/etiologia
17.
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
18.
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
19.
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
20.
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
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