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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.
Lung ; 194(4): 581-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27164984

RESUMO

PURPOSE: Aging is associated with changes in the lung that leads to a decrease in its function. Alterations in structure and function in the small airways are well recognized in chronic lung diseases. The aim of this study was the assessment of cell turnover in the bronchiolar epithelium of mouse through the normal aging process. METHODS: Lungs from CD1 mice at the age of 2, 6, 12, 18, or 24 months were fixed in neutral-buffered formalin and paraffin-embedded. Proliferating cell nuclear antigen was examined by immunohistochemistry. Apoptosis was analyzed by in situ end-labeling of fragmented DNA. Epithelial dimensions were analyzed by morphometry. RESULTS: The 2-month-old mice showed significantly higher number of proliferating cells when compared with mice at all other age groups. The number of apoptotic cells in mice at 24 months of age was significantly greater than in mice at all other age groups. Thus, the number of epithelial cells decreased as the age of the subject increased. We also found reductions in both area and height of the bronchiolar epithelium in mice at 18 and 24 months of age. CONCLUSIONS: We found a decrease in the total number of epithelial cells in the aged mice, which was accompanied by a thinning of the epithelium. These changes reflect a dysregulated tissue regeneration process in the bronchiolar epithelium that might predispose to respiratory diseases in elderly subjects.


Assuntos
Envelhecimento/fisiologia , Bronquíolos/citologia , Bronquíolos/fisiologia , Células Epiteliais/fisiologia , Epitélio/fisiologia , Animais , Apoptose , Proliferação de Células , Senescência Celular , Epitélio/anatomia & histologia , Masculino , Camundongos , Antígeno Nuclear de Célula em Proliferação/metabolismo
3.
J Cell Mol Med ; 19(11): 2679-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26257389

RESUMO

Regeneration of the lung airway epithelium after injury has been extensively studied. In contrast, analysis of its turnover in healthy adulthood has received little attention. In the classical view, this epithelium is maintained in the steady-state by the infrequent proliferation of basal or Clara cells. The intermediate filament protein nestin was initially identified as a marker for neural stem cells, but its expression has also been detected in other stem cells. Lungs from CD1 mice at the age of 2, 6, 12, 18 or 24 months were fixed in neutral-buffered formalin and paraffin-embedded. Nestin expression was examined by an immunohistochemical peroxidase-based method. Nestin-positive cells were detected in perivascular areas and in connective tissue that were in close proximity of the airway epithelium. Also, nestin-positive cells were found among the cells lining the airway epithelium. These findings suggest that nestin-positive stem cells circulate in the bloodstream, transmigrate through blood vessels and localize in the lung airway epithelium to participate in its turnover. We previously reported the existence of similar cells able to differentiate into lung chondrocytes. Thus, the stem cell reported here might be a bone marrow-derived mesenchymal stem cell (BMDMSC) able to generate several types of lung tissues. In conclusion, our findings indicate that there exist a BMDMSC in healthy adulthood that participates in the turnover of the lung airway epithelium. These findings may improve our knowledge about the lung stem cell biology and also provide novel approaches to therapy for devastating pulmonary diseases.


Assuntos
Células-Tronco Mesenquimais , Nestina , Mucosa Respiratória/fisiologia , Animais , Diferenciação Celular , Pulmão/citologia , Pulmão/fisiologia , Pneumopatias/terapia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Regeneração
4.
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.

5.
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
6.
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
7.
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
8.
In Vitro Cell Dev Biol Anim ; 46(9): 758-63, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20835776

RESUMO

It has been reported that 50-60 Hz magnetic fields (MF) with flux densities ranging from microtesla to millitesla are able to induce heat shock factor or heat shock proteins in various cells. In this study, we investigated the effect of 60 Hz sinusoidal MF at 8 and 80 µT on the expression of the luciferase gene contained in a plasmid labeled as electromagnetic field-plasmid (pEMF). This gene construct contains the specific sequences previously described for the induction of hsp70 expression by MF, as well as the reporter for the luciferase gene. The pEMF vector was transfected into INER-37 and RMA E7 cell lines that were later exposed to either MF or thermal shock (TS). Cells that received the MF or TS treatments and their controls were processed according to the luciferase assay system for evaluate luciferase activity. An increased luciferase gene expression was observed in INER-37 cells exposed to MF and TS compared with controls (p < 0.05), but MF exposure had no effect on the RMA E7 cell line.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Luciferases/genética , Magnetismo/métodos , Regiões Promotoras Genéticas/fisiologia , Ativação Transcricional , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Regiões Promotoras Genéticas/genética , Transfecção
9.
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
10.
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
11.
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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