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1.
Methods Mol Biol ; 1651: 205-212, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28801909

RESUMO

Gene expression can be modified by physical factors, such as heat, electricity and magnetic fields , and several types of ionizing and non-ionizing radiation. Promoter activation with extremely low-frequency electromagnetic fields is possible with an appropriate promoter, containing electromagnetic field response elements. Here, we describe how to examine promoter activation with extremely low-frequency electromagnetic fields, and we provide a step-by-step guide to the assembly of a solenoid suitable for promoter activation.


Assuntos
Campos Eletromagnéticos , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Transfecção/métodos , Animais , Linhagem Celular , Eletroporação/métodos , Vetores Genéticos/genética , Células HeLa , Humanos , Luciferases/genética , Camundongos , Camundongos Endogâmicos BALB C
2.
Environ Entomol ; 46(2): 376-382, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334331

RESUMO

Worldwide mobile telephone and microwave use have resulted in an increasing presence of extremely low-frequency electromagnetic field radiations (ELF-EMFs) in ecosystems. ELF-EMFs have been associated with altered physiological processes that can adversely affect exposed organisms. In this study, Trichoplusia ni Hübner larvae were exposed for 24, 48, or 72 h to ELF-EMFs (60 Hz and 2.0 mT) to assess effects on immune response parameters and fertility. Trichoplusia ni life cycle and fertility were not affected by 24-h exposure. However, the number of apoptotic-like cells and cellular immune response significantly increased (P < 0.01) after 72-h exposure (2- and 1.1-fold, respectively), whereas hemolymph total protein and hemocyte cells were reduced (P < 0.01; 16 and 50%, respectively) after 48-h exposure. Hemocyte cell type analysis resulted in significantly (P < 0.01) higher granulocytes number in the unexposed (2-fold increase) and oenocytoids in the 72-h-exposed larvae (28.6-fold increase). Quantitative retrotranscription (RT-qPCR) showed that after 72-h ELF-EMF exposure, the antimicrobial peptides cecropin, lysozyme, gallerimycin, and pgrp were downregulated by 24,866.0, 2.69-, 119.1-, and 1.45-fold, respectively, whereas attacin and defensin were upregulated by 1.59- and 1.85-fold, respectively. The effect of ELF-EMFs on the T. ni larvae immune response and their potential impact on its physiology and susceptibility to pathogens are discussed. This information may provide new insight of ELF-EMFs on other pest species, as well as for the preservation of ecologically important species.


Assuntos
Campos Eletromagnéticos , Fertilidade/efeitos da radiação , Imunidade Celular/efeitos da radiação , Imunidade Humoral/efeitos da radiação , Lepidópteros/efeitos da radiação , Animais , Feminino , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/efeitos da radiação , Lepidópteros/crescimento & desenvolvimento , Lepidópteros/imunologia , Lepidópteros/fisiologia , Masculino
3.
Cell Biol Int Rep (2010) ; 19(1): e00014, 2012 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-23124775

RESUMO

Exposure to EMFs (electromagnetic fields) results in a number of important biological changes, including modification of genetic expression. We have investigated the effect of 60 Hz sinusoidal EMFs at a magnetic flux density of 80 µT on the expression of the luciferase gene contained in a plasmid labelled as pEMF (EMF plasmid). This gene construct contains the specific sequences for the induction of hsp70 (heat-shock protein 70) expression by EMFs, as well as the reporter for the luciferase gene. The pEMF vector was electrotransferred into quadriceps muscles of BALB/c mice that were later exposed to EMFs. Increased luciferase expression was observed in mice exposed to EMFs 2 h daily for 7 days compared with controls (P<0.05). These data along with other reports in the literature suggest that EMFs can have far-reaching effects on the genome.

4.
Biol Trace Elem Res ; 147(1-3): 180-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22147334

RESUMO

Zeolites, especially clinoptilolites, have wide application in removing heavy metals from different solutions and wastewater. The detoxification capacity of the clinoptilolite sorbent KLS-10-MA, a modified natural Bulgarian zeolite, applied as a food supplement in conditions of an ecotoxicological experiment with conventional food and lead was demonstrated for the first time. Laboratory mice, inbred imprinting control region strain, were used in a 90-day ecotoxicological experiment. Animals were divided into four experimental groups. Lead bioaccumulations in exposed and non-supplemented/supplemented with KLS-10-MA animals were compared. As additional control, healthy animals non-exposed to Pb were fed with conventional forage mixed with 12.5% KLS-10-MA. The dietary inclusion of the sorbent reduced Pb concentrations in exposed and supplemented mice by 84%, 89%, 91%, 77%, and 88% in carcass, liver, kidneys, bones, and feces, respectively. A mathematical model was proposed to outline the common trends of bone Pb bioaccumulation in exposed and non-supplemented/supplemented animals. Characteristic parameters of the kinetics of Pb concentrations were determined. Based on the model, the coefficient of absorption of Pb by gastrointestinal mucosa in the supplemented mice was found-η = 3.53% (versus η = 15% in non-supplemented ones). The present study clearly indicates that there is a realistic perspective to create a new drug based on modified natural clinoptilolites in cases of chronic heavy metal intoxication, without negatively affecting the environment.


Assuntos
Algoritmos , Chumbo/farmacocinética , Chumbo/toxicidade , Modelos Biológicos , Zeolitas/farmacologia , Adsorção , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Bulgária , Fezes/química , Geografia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Cinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Distribuição Tecidual/efeitos dos fármacos , Zeolitas/química
5.
Biol Trace Elem Res ; 147(1-3): 206-16, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22144018

RESUMO

The detoxification capacity of the clinoptilolite modification KLS-10-MA used as food additive in small mammals, chronically lead-exposed, was proven for the first time. The modified clinoptilolite was prepared based on natural Bulgarian clinoptilolite deposits. As a powder, it was mechanically mixed at 12.5% concentration with the conventional forage for small rodents. Lead in the form of aqueous solution of Pb(NO(3))(2) was diluted in the drinking water. In the ecotoxicological experiment covering 90 days, imprinting control region laboratory mice were used. They were allocated into four groups: group 1, (control): animals fed with conventional food for small rodents and water; group 2: animals fed with conventional food + clinosorbent KLS-10-MA and water; group 3: animals fed with conventional food and water + Pb(NO(3))(2); and group 4: animals fed with conventional food + KLS-10-MA and water + Pb(NO(3))(2). A group of non-exposed healthy animals was fed with conventional forage mixed with KLS-10-MA to prove eventual toxicity of the sorbent and influence on growth performance. The changes in the chromosome structure, mitotic index, erythrocyte form, erythropoiesis, and body weight gain were recorded. On day 90, the following relations were established: Pb-exposed and clinoptilolite-supplemented mice exhibited 2.3-fold lower chromosome aberrations frequency, 2.5-fold higher mitotic index, and 1.5-fold higher percentage normal erythrocytes 1.3-fold higher body weight compared to Pb-exposed and unsupplemented animals. The obtained data showed that the sorbent is practically non-toxic. The results of the present study encourage a further elaboration of a reliable drug based on the tested substance in the cases of chronic lead intoxication.


Assuntos
Aberrações Cromossômicas/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Chumbo/toxicidade , Zeolitas/farmacologia , Adsorção , Algoritmos , Animais , Peso Corporal/efeitos dos fármacos , Bulgária , Proliferação de Células/efeitos dos fármacos , Eritrócitos/patologia , Eritropoese/efeitos dos fármacos , Chumbo/administração & dosagem , Chumbo/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Índice Mitótico , Modelos Biológicos , Modelos Genéticos , Nitratos/administração & dosagem , Nitratos/farmacocinética , Nitratos/toxicidade , Fatores de Tempo , Zeolitas/química
6.
Exp Parasitol ; 127(1): 80-3, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20603119

RESUMO

The influence of low-frequency electromagnetic (LF-EM) waves on microorganisms has been a subject of experimental investigations for more than two decades and the results are promising. In parallel, an interesting procedure known as biophysical-information-therapy or bioresonance therapy (BRT) which in principle is based on LF-EM stimulation, has emerged. BRT was discovered in the late 1980's but it is still poorly studied. This paper demonstrates that by transferring metronidazole information to water samples by an electronic amplifier (BRT device), the growth of axenically cultured trophozoites of Entamoeba histolytica and Trichomonasvaginalis is significantly inhibited, compared with those cultures treated with non and sham electro-transferred water samples. A positive control of metronidazole, a well-known cytotoxic drug against parasites, was used as a reference.


Assuntos
Antiprotozoários/farmacologia , Entamoeba histolytica/crescimento & desenvolvimento , Metronidazol/farmacologia , Radiossensibilizantes/farmacologia , Trichomonas vaginalis/crescimento & desenvolvimento , Água/química , Bioensaio , Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/efeitos da radiação , Radiação , Trichomonas vaginalis/efeitos dos fármacos , Trichomonas vaginalis/efeitos da radiação , Água/farmacologia
7.
Cell Biol Int ; 33(3): 419-23, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18957326

RESUMO

We have evaluated the effect of 60 Hz sinusoidal magnetic fields (MF) at 8 and 8 microT on expression of the luciferase gene contained in a gene construct labelled as Electromagnetic Field-plasmid (pEMF). The vector included the hsp70 promotor containing the 3 nCTCTn sequences previously described for the induction of hsp70 expression by magnetic fields, as well as the reporter of the luciferase gene. We also replicated the study of Lin et al. [Lin H, Blank M, Rossol-Haseroth K, Goodman R. Regulating genes with electromagnetic response elements. J Cell Biochem 2001;81(1):143-48]. The pEMF plasmid was transfected into HeLa and BMK16 cell lines that were later exposed to either MF or thermal shock (TS). An increased luciferase expression was found in both the cells exposed to MF and TS compared with their control groups (P < 0.05). Furthermore, the combined effect of MF and TS was also analyzed. A synergistic effect between two factors was observed for this co-exposure condition in terms of luciferase gene expression.


Assuntos
Campos Eletromagnéticos , Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Regiões Promotoras Genéticas , Animais , Linhagem Celular Tumoral , Genes Reporter , Células HeLa , Humanos , Luciferases/biossíntese , Camundongos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo
8.
Exp Parasitol ; 119(2): 202-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18396281

RESUMO

Exposure to extremely low-frequency (ELF) electromagnetic fields appears to result in a number of important biological changes. In the present study, we evaluated the effects of 60 Hz sinusoidal magnetic fields (MF) at magnetic flux densities of 1.0, 1.5 and 2.0 mT on growth and differentiation of the protozoan Entamoeba invadens. We demonstrated an inhibitory growth effect when trophozoite cultures were exposed to 1.5 and 2.0 mT. Furthermore, we found that there was not a synergistic effect in cultures co-exposed to MF and Metronidazole, a cytotoxic drug against amoebic cells. In addition, MF exposure inhibited the encystation process of E. invadens.


Assuntos
Campos Eletromagnéticos , Entamoeba/crescimento & desenvolvimento , Entamoeba/efeitos da radiação , Animais , Antiprotozoários/farmacologia , Relação Dose-Resposta à Radiação , Entamoeba/efeitos dos fármacos , Entamoeba/fisiologia , Dose Letal Mediana , Metronidazol/farmacologia , Distribuição Aleatória
9.
Bioelectromagnetics ; 25(1): 63-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14696055

RESUMO

The effect of in vivo exposure of mice to a 60 Hz sinusoidal magnetic field (MF) at 2.0 mT on male germ cells was studied. The cytological endpoints measured included meiotic chromosome aberrations in spermatocytes and sperm morphology. Three independent experiments were carried out: (a) animals exposed for 72 h, (b) 10 days/8 h daily, and (c) 72 h exposure to MF plus 5 mg/kg of Mitomycin-C. No statistically significant differences indicative of MF effects were observed between MF exposed and control animals. In addition, an opposite effect between MF exposure and Mitomycin-C treatment in terms of chromosomal aberrations and sperm morphology was observed.


Assuntos
Aberrações Cromossômicas , Cromossomos/efeitos da radiação , Eletricidade , Campos Eletromagnéticos , Meiose/genética , Meiose/efeitos da radiação , Espermatozoides/patologia , Espermatozoides/efeitos da radiação , Animais , Tamanho Celular/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Doses de Radiação , Irradiação Corporal Total
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