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1.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298941

RESUMO

Clinical research aiming at objectively identifying and characterizing diseases via clinical observations and biological and radiological findings is a critical initial research step when establishing objective diagnostic criteria and treatments. Failure to first define such diagnostic criteria may lead research on pathogenesis and etiology to serious confounding biases and erroneous medical interpretations. This is particularly the case for electrohypersensitivity (EHS) and more particularly for the so-called "provocation tests", which do not investigate the causal origin of EHS but rather the EHS-associated particular environmental intolerance state with hypersensitivity to man-made electromagnetic fields (EMF). However, because those tests depend on multiple EMF-associated physical and biological parameters and have been conducted in patients without having first defined EHS objectively and/or endpoints adequately, they cannot presently be considered to be valid pathogenesis research methodologies. Consequently, the negative results obtained by these tests do not preclude a role of EMF exposure as a symptomatic trigger in EHS patients. Moreover, there is no proof that EHS symptoms or EHS itself are caused by psychosomatic or nocebo effects. This international consensus report pleads for the acknowledgement of EHS as a distinct neuropathological disorder and for its inclusion in the WHO International Classification of Diseases.


Assuntos
Biomarcadores/metabolismo , Hipersensibilidade/metabolismo , Sensibilidade Química Múltipla/metabolismo , Animais , Consenso , Diagnóstico por Imagem/métodos , Testes Diagnósticos de Rotina/métodos , Campos Eletromagnéticos , Humanos , Doenças do Sistema Nervoso/metabolismo
3.
Toxicol In Vitro ; 22(6): 1489-95, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18572378

RESUMO

The homeodomain transcription factors PHOX2A and PHOX2B are vital for development of the autonomic nervous system. Their spatial and temporal expression at the neural crest is instrumental in determining neuronal precursor fate, and by regulating DbetaH expression, the enzyme catalysing noradrenaline synthesis from dopamine, they also play a role in determination of noradrenergic phenotype. Disturbing this finely regulated process leads to disruption of autonomic development and autonomic dysfunction syndromes such as DbetaH deficiency. As it had previously been shown that the catecholamine system is responsive to ELF-EMF, and as this has also been linked to various pathologies and to certain types of cancer, we wondered whether exposure to this type of radiation could affect the expression of PHOX2A, PHOX2B and DbetaH, also during differentiation triggered by retinoic acid. To investigate this possibility we exposed the human SH-SY5Y neuroblastoma cell line to 50 Hz power-line magnetic field at various flux densities and for various exposure times. We measured gene expression in exposed cells compared to control cells and also investigated any changes at protein level. Using our exposure protocol, we found no changes at either transcript or protein level of these important components of the autonomic nervous system and catecholaminergic system.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Expressão Gênica/efeitos da radiação , Proteínas de Homeodomínio/efeitos da radiação , Fatores de Transcrição/efeitos da radiação , Linhagem Celular Tumoral , Dopamina beta-Hidroxilase/efeitos da radiação , Humanos , Neuroblastoma/metabolismo , Fatores de Tempo , Transcrição Gênica/efeitos da radiação , Tretinoína/farmacologia
4.
Int Arch Occup Environ Health ; 81(6): 755-67, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18278508

RESUMO

OBJECTIVE: Universal Mobile Telecommunication System (UMTS) was recently introduced as the third generation mobile communication standard in Europe. This was done without any information on biological effects and genotoxic properties of these particular high-frequency electromagnetic fields. This is discomforting, because genotoxic effects of the second generation standard Global System for Mobile Communication have been reported after exposure of human cells in vitro. METHODS: Human cultured fibroblasts of three different donors and three different short-term human lymphocyte cultures were exposed to 1,950 MHz UMTS below the specific absorption rate (SAR) safety limit of 2 W/kg. The alkaline comet assay and the micronucleus assay were used to ascertain dose and time-dependent genotoxic effects. Five hundred cells per slide were visually evaluated in the comet assay and comet tail factor (CTF) was calculated. In the micronucleus assay 1,000 binucleated cells were evaluated per assay. The origin of the micronuclei was determined by fluorescence labeled anticentromere antibodies. All evaluations were performed under blinded conditions. RESULTS: UMTS exposure increased the CTF and induced centromere-negative micronuclei (MN) in human cultured fibroblasts in a dose and time-dependent way. Incubation for 24 h at a SAR of 0.05 W/kg generated a statistically significant rise in both CTF and MN (P = 0.02). At a SAR of 0.1 W/kg the CTF was significantly increased after 8 h of incubation (P = 0.02), the number of MN after 12 h (P = 0.02). No UMTS effect was obtained with lymphocytes, either unstimulated or stimulated with Phytohemagglutinin. CONCLUSION: UMTS exposure may cause genetic alterations in some but not in all human cells in vitro.


Assuntos
Telefone Celular , DNA/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Fibroblastos/efeitos da radiação , Linfócitos/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Adulto , Células Cultivadas , Criança , Ensaio Cometa , Dano ao DNA/efeitos da radiação , Feminino , Humanos , Masculino , Testes para Micronúcleos/métodos , Pessoa de Meia-Idade , Doses de Radiação , Ondas de Rádio/efeitos adversos
5.
Mutat Res ; 585(1-2): 43-9, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16009595

RESUMO

Environmental exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) has been implicated in the development of cancer in humans. An important basis for assessing a potential cancer risk due to ELF-EMF exposure is knowledge of biological effects on human cells at the chromosomal level. Therefore, we investigated in the present study the effect of intermittent ELF electromagnetic fields (50 Hz, sinusoidal, 5'field-on/10'field-off, 2-24 h, 1 mT) on the induction of micronuclei (MN) and chromosomal aberrations in cultured human fibroblasts. ELF-EMF radiation resulted in a time-dependent increase of micronuclei, which became significant after 10 h of intermittent exposure at a flux density of 1 mT. After approximately 15 h a constant level of micronuclei of about three times the basal level was reached. In addition, chromosomal aberrations were increased up to 10-fold above basal levels. Our data strongly indicate a clastogenic potential of intermittent low-frequency electromagnetic fields, which may lead to considerable chromosomal damage in dividing cells.


Assuntos
Aberrações Cromossômicas , Campos Eletromagnéticos/efeitos adversos , Fibroblastos/fisiologia , Células Cultivadas , Dano ao DNA/genética , Diploide , Humanos , Masculino , Testes para Micronúcleos , Testes de Mutagenicidade
6.
Mutat Res ; 583(2): 178-83, 2005 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-15869902

RESUMO

Cultured human diploid fibroblasts and cultured rat granulosa cells were exposed to intermittent and continuous radiofrequency electromagnetic fields (RF-EMF) used in mobile phones, with different specific absorption rates (SAR) and different mobile-phone modulations. DNA strand breaks were determined by means of the alkaline and neutral comet assay. RF-EMF exposure (1800 MHz; SAR 1.2 or 2 W/kg; different modulations; during 4, 16 and 24h; intermittent 5 min on/10 min off or continuous wave) induced DNA single- and double-strand breaks. Effects occurred after 16 h exposure in both cell types and after different mobile-phone modulations. The intermittent exposure showed a stronger effect in the comet assay than continuous exposure. Therefore we conclude that the induced DNA damage cannot be based on thermal effects.


Assuntos
Telefone Celular , Dano ao DNA , Fibroblastos/efeitos da radiação , Células da Granulosa/efeitos da radiação , Micro-Ondas/efeitos adversos , Animais , Linhagem Celular Transformada , Ensaio Cometa , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Ratos , Fatores de Tempo
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