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1.
Bioelectromagnetics ; 39(3): 217-230, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29125193

RESUMO

Exposure to specific electromagnetic field (EMF) patterns can affect a variety of biological systems. We have shown that exposure to Thomas-EMF, a low-intensity, frequency-modulated (25-6 Hz) EMF pattern, inhibited growth and altered cell signaling in malignant cells. Exposure to Thomas-EMF for 1 h/day inhibited the growth of malignant cells including B16-BL6 mouse melanoma cells, MDA-MB-231, MDA-MB-468, BT-20, and MCF-7 human breast cancer and HeLa cervical cancer cells but did not affect non-malignant cells. The Thomas-EMF-dependent changes in cell proliferation were mediated by adenosine 3',5'-cyclic monophosphate (cAMP) and extracellular-signal-regulated kinase (ERK) signaling pathways. Exposure of malignant cells to Thomas-EMF transiently changed the level of cellular cAMP and promoted ERK phosphorylation. Pharmacologic inhibitors (SQ22536) and activators (forskolin) of cAMP production both blocked the ability of Thomas-EMF to inhibit cell proliferation, and an inhibitor of the MAP kinase pathway (PD98059) was able to partially block Thomas-EMF-dependent inhibition of cell proliferation. Genetic modulation of protein kinase A (PKA) in B16-BL6 cells also altered the effect of Thomas-EMF on cell proliferation. Cells transfected with the constitutively active form of PKA (PKA-CA), which interfered with ERK phosphorylation, also interfered with the Thomas-EMF effect on cell proliferation. The non-malignant cells did not show any EMF-dependent changes in cAMP levels, ERK phosphorylation, or cell growth. These data indicate that exposure to the specific Thomas-EMF pattern can inhibit the growth of malignant cells in a manner dependent on contributions from the cAMP and MAP kinase pathways. Bioelectromagnetics. 39;217-230, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
AMP Cíclico/metabolismo , Campos Eletromagnéticos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Camundongos , Fosforilação/efeitos da radiação , Fatores de Tempo
2.
Bioelectromagnetics ; 38(3): 165-174, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28026051

RESUMO

Exposure to low intensity, low frequency electromagnetic fields (EMF) has effects on several biological systems. Spatiotemporal characteristics of these EMFs are critical. The effect of several complex EMF patterns on the proliferation of B16-BL6 mouse melanoma cells was tested. Exposure to one of these patterns, the Thomas-EMF, inhibited cell proliferation and promoted calcium uptake. The Thomas-EMF is coded from a digital-to-analog file comprised of 849 points, which provides power to solenoids and can be set to alter timing, intensity, and duration of variable EMF. Setting the point duration to 3 ms generated a time-varying EMF pattern which began at 25 Hz and slowed to 6 Hz over a 2.5 s repeat. Exposing B16-BL6 cells to Thomas-EMF set to 3 ms for 1 h/day inhibited cell proliferation by 40% after 5 days, while setting the point duration to 1, 2, 4, or 5 ms had no effect on cell proliferation. Similarly, exposing cells to Thomas-EMF set to 3 ms promoted a three-fold increase in calcium uptake after 1 h, while the other timings had no effect. Exposure to Thomas-EMF for as short as 15 min/day slowed cell proliferation, but exposure for 1 h/day was optimal. This corresponded to the effect on calcium uptake where uptake was detected after 15 min exposure and was maximal by 1 h of treatment. Studies show that the specific spatiotemporal character of EMF is critical in mediating their biological activities. Bioelectromagnetics. 38:165-174, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Campos Eletromagnéticos , Melanoma Experimental/patologia , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Magnetoterapia , Melanoma Experimental/metabolismo , Melanoma Experimental/terapia , Camundongos , Fatores de Tempo
3.
J Radiol Prot ; 36(1): R23-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26910391

RESUMO

Exposure to ionising radiation is clearly associated with an increased risk of developing some types of cancer. However, the contribution of non-targeted effects to cancer development after exposure to ionising radiation is far less clear. The currently used cancer risk model by the international radiation protection community states that any increase in radiation exposure proportionately increases the risk of developing cancer. However, this stochastic cancer risk model does not take into account any contribution from non-targeted effects. Nor does it consider the possibility of a bystander mechanism in the induction of genomic instability. This paper reviews the available evidence to date for a possible role for non-targeted effects to contribute to cancer development after exposure to ionising radiation. An evolution in the understanding of the mechanisms driving non-targeted effects after exposure to ionising radiation is critical to determine the true contribution of non-targeted effects on the risk of developing cancer. Such an evolution will likely only be achievable through coordinated multidisciplinary teams combining several fields of study including: genomics, proteomics, cell biology, molecular epidemiology, and traditional epidemiology.


Assuntos
Carcinogênese , Neoplasias Induzidas por Radiação/etiologia , Efeito Espectador/efeitos da radiação , Instabilidade Genômica/efeitos da radiação , Humanos , Proteção Radiológica , Risco
4.
Cancer Causes Control ; 26(10): 1421-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26208590

RESUMO

PURPOSE: Previously published findings have documented increased breast cancer risks associated with the nursing profession. The aim of the present study was to assess whether an increased risk of breast cancer was associated with nursing in a population-based case-control breast cancer study of women in Northeastern Ontario, Canada. METHODS: A total of 1519 women (1380 never-nurses: 716 controls and 664 cases; 139 ever-nurses: 59 controls and 80 cases) were included in the present study. Study participants filled out a detailed questionnaire which included a history of smoking, general health information, breast cancer risk factors, and a detailed occupational history. RESULTS: Ever-nurses were at higher, but nonsignificant risk of breast cancer compared to never-nurses (adjusted OR 1.39, 95 % CI 0.93-2.07). Ever-nurses who worked for longer than 10 years were at a significantly increased risk of breast cancer compared to never-nurses (adjusted OR 1.70, 95 % CI 1.04-2.79). A nonsignificant, but increased risk of breast cancer was observed in ever-nurses who worked full-time compared to never-nurses (OR 1.52, 95 % CI 0.92-2.52), while nurses who worked part-time, or both part-time and full-time were not at increased risk. Ever-nurses who worked in a hospital setting had a significantly increased risk of breast cancer (OR 1.65, 95 % CI 1.04-2.62) compared to never-nurses. CONCLUSIONS: The results indicate that the nurses in the present study population are at increased risk of breast cancer. A prolonged duration of nursing years and prolonged intensity (being a full-time nurse) are factors associated with this increased risk.


Assuntos
Neoplasias da Mama/epidemiologia , Enfermeiras e Enfermeiros , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Ontário , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e Questionários
5.
Naturwissenschaften ; 101(2): 87-94, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24424785

RESUMO

During the first 24 h after removal from incubation, melanoma cells in culture displayed reliable increases in emissions of photons of specific wavelengths during discrete portions of this interval. Applications of specific filters revealed marked and protracted increases in infrared (950 nm) photons about 7 h after removal followed 3 h later by marked and protracted increases in near ultraviolet (370 nm) photon emissions. Specific wavelengths within the visible (400 to 800 nm) peaked 12 to 24 h later. Specific activators or inhibitors for specific wavelengths based upon Cosic's resonant recognition model elicited either enhancement or diminishment of photons at the specific wavelength as predicted. Inhibitors or activators predicted for other wavelengths, even within 10 nm, were less or not effective. There is now evidence for quantitative coupling between the wavelength of photon emissions and intrinsic cellular chemistry. The results are consistent with initial activation of signaling molecules associated with infrared followed about 3 h later by growth and protein-structural factors associated with ultraviolet. The greater-than-expected photon counts compared with raw measures through the various filters, which also function as reflective material to other photons, suggest that photons of different wavelengths might be self-stimulatory and could play a significant role in cell-to-cell communication.


Assuntos
Substâncias Macromoleculares/química , Melanoma Experimental/fisiopatologia , Modelos Teóricos , Fótons , Luz , Melanoma Experimental/química , Células Tumorais Cultivadas , Raios Ultravioleta
6.
Gen Physiol Biophys ; 33(1): 63-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23970034

RESUMO

If parameters for lateral diffusion of lipids within membranes are macroscopic metaphors of the angular magnetic moment of the Bohr magneton then the energy emission should be within the visible wavelength for applied ~1 µT magnetic fields. Single or paired digital photomultiplier tubes (PMTs) were placed near dishes of ~1 million B16 mouse melanoma cells that had been removed from incubation. In very dark conditions (10(-11) W/m(2)) different averaged (RMS) intensities between 5 nT and 3.5 µT were applied randomly in 4 min increments. Numbers of photons were recorded directly over or beside the cell dishes by PMTs placed in pairs within various planes. Spectral analyses were completed for photon power density. The peak photon emissions occurred around 1 µT as predicted by the equation. Spectra analyses showed reliable discrete peaks between 0.9 and 1.8 µT but not for lesser or greater intensities; these peak frequencies corresponded to the energy difference of the orbital-spin magnetic moment of the electron within the applied range of magnetic field intensities and the standard solution for Rydberg atoms. Numbers of photons from cooling cells can be modified by applying specific intensities of temporally patterned magnetic fields. There may be a type of "cellular" magnetic moment that, when stimulated by intensity-tuned magnetic fields, results in photon emissions whose peak frequencies reflect predicted energies for fundamental orbital/spin properties of the electron and atomic aggregates with large principal quantum numbers.


Assuntos
Magnetismo , Melanoma Experimental/diagnóstico , Melanoma/diagnóstico , Animais , Lipídeos/química , Campos Magnéticos , Melanoma/patologia , Melanoma Experimental/patologia , Camundongos , Fotoquímica/métodos , Fótons , Processamento de Sinais Assistido por Computador , Software , Espectrofotometria/métodos , Fatores de Tempo
7.
FEBS Open Bio ; 14(3): 515-524, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38143305

RESUMO

Exposure to time-varying electromagnetic fields (EMF) has the capacity to influence biological systems. Our results demonstrate that exposure to time-varying EMF modeled after the physiological firing frequency of intercellular calcium waves can inhibit proliferation and induce apoptosis in malignant cells. Single exposure of B16-BL6 cells to a Ca2+ EMF for 40 min reduced the number of viable cells by 50.3%. Cell imaging with acridine orange and ethidium bromide dye revealed substantial cellular apoptosis, preapoptotic cells, nuclear fragmentation, and large spacing between cells in the Ca2+ EMF condition when compared to the control condition. The ability of Ca2+ EMF to influence the proliferation and survival of malignant cells suggests that exposure to specific EMF may function as a potential anticancer therapy.


Assuntos
Sinalização do Cálcio , Melanoma Experimental , Animais , Humanos , Campos Eletromagnéticos , Apoptose , Fatores de Tempo
8.
J Antimicrob Chemother ; 65(4): 684-93, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20159770

RESUMO

OBJECTIVES: This study examined the activities of tobramycin and bismuth against quorum sensing, virulence factors and biofilms of Pseudomonas aeruginosa by co-encapsulating the agents in liposomes in order to achieve greater delivery of the agents. METHODS: The inhibitory effects of the agents, in either their conventional (free) or vesicle-entrapped (liposomal) formulations, were assessed by measuring the changes in the quorum-sensing signal molecule N-acyl homoserine lactone, pyoverdine, pyocyanin, elastase, protease, chitinase, bacterial attachment and biofilms in vitro. RESULTS: The effectiveness of tobramycin and bismuth was superior when they were co-administered as a liposomal formulation as measured by their ability to attenuate the production of N-acyl homoserine lactone, elastase (P < 0.01), protease (P < 0.05) and chitinase (P < 0.01). In the presence of non-lethal concentrations of free and liposomal tobramycin and bismuth, bacterial attachment was attenuated. Biofilm formation was also attenuated with free tobramycin and bismuth, yet, in the presence of liposomal tobramycin and bismuth, biofilm complexes could form but contained mostly dead bacteria. When established biofilms were treated with higher concentrations, free tobramycin and bismuth killed and detached bacteria, while the liposomal tobramycin and bismuth penetrated and killed bacteria in the cores of the biofilms. CONCLUSIONS: These data suggest that treatment of P. aeruginosa with tobramycin and bismuth, as measured by the changes in quorum sensing, virulence factors and biofilms, is most effective when delivered as a liposomal formulation at a lower concentration compared with the free formulation.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Lipossomos/farmacocinética , Mercaptoetanol/análogos & derivados , Pseudomonas aeruginosa/efeitos dos fármacos , Tobramicina/farmacologia , Fatores de Virulência/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Humanos , Lipossomos/farmacologia , Mercaptoetanol/farmacocinética , Mercaptoetanol/farmacologia , Percepção de Quorum/efeitos dos fármacos , Tobramicina/farmacocinética
9.
Heliyon ; 5(8): e02251, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31440598

RESUMO

Flaxseed oil is widely recognized for its exceptional nutritional value, high concentration of fiber-based lignans and large amounts of ω-fatty acids. It is one of a generic group of functional foods that is often taken by cancer patients as a potential treatment. We have examined the anti-cancer effects of flaxseed oil by studying its direct effects on cancer cell growth in vitro. Treatment of a variety of cancer cell lines with flaxseed oil decreased their growth in a dose-dependent manner while non-malignant cell lines showed small increases in cell growth. Cells treated with a mixture of fatty acids, including α-linolenic acid, docosahexaenoic acid, and eicosapentaenoic acid and lignans including enterodiol and enterolactone was also able to decrease the growth of cancer cells. Treatment of B16-BL6 murine melanoma and MCF-7 breast cancer cells with flaxseed oil induced apoptosis as determined by changes in cell morphology, annexin V staining, DNA fragmentation and/or caspase activation. In addition, treatment with flaxseed oil also disrupted mitochondrial function in B16-BL6 and MCF-7 cells. These results indicate that flaxseed oil can specifically inhibit cancer cell growth and induce apoptosis in some cancer cells and suggests it has further potential in anti-cancer therapy.

10.
Clin Breast Cancer ; 19(6): 433-442, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31383605

RESUMO

BACKGROUND: The frequency of circulating leukocytes has been shown to be a prognostic factor in patients being treated for different types of cancer. In breast cancer, tumor-infiltrating leukocytes may predict patient outcome, but few studies have investigated such associations for circulating leukocytes. PATIENTS AND METHODS: Multiparametric flow cytometry was used to examine the immunophenotypes of circulating peripheral blood mononuclear cells for 88 patients with metastatic breast cancer, which was then correlated to breast cancer-specific survival. Patients had been treated either with high-dose cyclophosphamide-containing regimens (group 1, n = 51 patients) or high-dose paclitaxel-containing regimens (group 2, n = 37 patients). RESULTS: The frequency of peripheral blood CD14+ monocytes indicated prognosis for patients in group 1 (but not group 2), while higher levels of CD11c+ dendritic cells indicated a better prognosis for patients in group 2 (but not group 1). The frequency of a number of different CD4+ or CD8+ T cell subtypes also predicted prognosis for patients in group 2. For example, patients in group 2 with a higher frequency of circulating CD4+ or CD8+ naive T cells (CD45RA+CD95-CD27+CD28+) showed a poorer prognosis. In contrast, T cells were not associated with prognosis for patients in group 1. CONCLUSION: Circulating leukocytes can predict clinical outcome for patients with breast cancer. Prediction of clinical outcome in this cohort of metastatic breast cancer patients was specific to the type of chemotherapy, and this finding is likely to apply to other therapies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/mortalidade , Células Dendríticas/imunologia , Leucócitos Mononucleares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Monócitos/imunologia , Recidiva Local de Neoplasia/mortalidade , Adulto , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Carboplatina/administração & dosagem , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Células Dendríticas/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Monócitos/efeitos dos fármacos , Metástase Neoplásica , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Paclitaxel/administração & dosagem , Prognóstico , Taxa de Sobrevida , Tiotepa/administração & dosagem , Vimblastina/administração & dosagem
11.
J Ethnopharmacol ; 109(2): 312-7, 2007 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-16959454

RESUMO

Uncaria tomentosa, commonly known as cat's claw, is a medicinal plant native to Peru, which has been used for decades in the treatment of various inflammatory disorders. Uncaria tomentosa can be used as an antioxidant, has anti-apoptotic properties, and can enhance DNA repair, however it is best know for its anti-inflammatory properties. Treatment with Uncaria tomentosa extracts inhibits the production of the pro-inflammatory cytokine, TNF-alpha, which is a critical mediator of the immune response. In this paper, we showed that treatment of THP-1 monocyte-like cells with Uncaria tomentosa extracts inhibited the MAP kinase signaling pathway and altered cytokine expression. Using ELISA assays, we showed that treatment with Uncaria tomentosa extracts augmented LPS-dependent expression of IL-1beta by 2.4-fold, while inhibiting the LPS-dependent expression of TNF-alpha by 5.5-fold. We also showed that treatment of LPS-stimulated THP-1 cells with Uncaria tomentosa extracts blocked ERK1/2 and MEK1/2 phosphorylation in a dose-dependent manner. These data demonstrate that treatment of THP-1 cells with Uncaria tomentosa extracts has opposite effects on IL-1beta and TNF-alpha secretion, and that these changes may involve effects on the MAP kinase pathway.


Assuntos
Unha-de-Gato/química , Interleucina-1beta/metabolismo , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Extratos Vegetais/química , Plantas Medicinais
12.
Pharmacognosy Res ; 9(3): 221-229, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28827961

RESUMO

BACKGROUND: Uncaria tomentosa (Willd. ex Schult.) DC (Rubiaceae), known as Cat's Claw or Uña de gato, is a traditionally used medicinal plant native to Peru. Some studies have shown that U. tomentosa can act as an antiapoptotic agent and enhance DNA repair in chemotherapy-treated cells although others have shown that U. tomentosa enhanced apoptosis. OBJECTIVE: To determine if treatment with U. tomentosa can significantly enhance cell death in THP-1 cells exposed to ionizing radiation. MATERIALS AND METHODS: THP-1 monocyte-like cells were treated with ethanolic extracts of U. tomentosa in the presence or absence of bacterial lipopolysaccharide and then exposed to ionizing radiation. Cell proliferation was assessed by MTT and clonogenic assays and the effects on cell cycle measured by flow cytometry and immunoblotting. Changes in cell signaling were determined by immunoblotting and cytokine ELISA and activation of apoptosis measured by caspase activation and DNA fragmentation analysis. RESULTS: Treatment of THP-1 cells with U. tomentosa had a small effect on cell proliferation. However, when the U. tomentosa-pretreated cells were also subjected to 5-9 Gy ionizing radiation, they showed a significant decrease in cell proliferation and increased cellular apoptosis as measured by DNA fragmentation and caspase activation. Treatment with U. tomentosa also decreased the expression of Cyclin E and Cyclin B, key regulators of normal cell cycle progression, and decreased the phosphorylation of various stress-activated, cell survival proteins including p38, ERK, and SAP/JNK kinase. CONCLUSIONS: These results suggest that U. tomentosa could be useful in enhancing cell death following anticancer therapies including ionizing radiation. SUMMARY: Treatment of THP-1 cells with Uncaria tomentosa increases their susceptibility to X-rays. The combination of Uncaria tomentosa and X-ray exposure strongly inhibits cell signaling and promotes apoptosis. Abbreviations Used: LPS: Lipopolysaccharide, TNF: Tumor necrosis factor: IL-1, Interleukin-1: SDS: Sodium dodecylsulphate, TBS: Tris-buffered saline.

13.
Curr Pharm Des ; 12(22): 2833-48, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16918414

RESUMO

Cellular adhesion molecules are critical components during carcinogenesis and cancer metastasis and contribute to the mechanisms underlying resistance to chemotherapeutic drugs. Since drug resistance is associated with a very poor prognosis for patients with cancer, a better understanding of the role of adhesion molecules could improve patient outcome by identifying novel mechanisms that promote drug resistance. Epigenetic factors, such as cellular adhesion, are shown to promote the resistance of cancers to various chemotherapeutic drugs by altering cellular signalling pathways that activate cellular growth and inhibit apoptosis. In addition, cellular adhesion molecules can provide a means to specifically target more conventional chemotherapy to the unique tumour microenvironment. However, the expression and function of cellular adhesion molecules, and the signals activated by adhesion, are highly interrelated making the development of rational therapies more difficult.


Assuntos
Antineoplásicos/administração & dosagem , Moléculas de Adesão Celular/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/imunologia , Animais , Moléculas de Adesão Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Transdução de Sinais/efeitos dos fármacos
14.
PLoS One ; 10(4): e0124136, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25875081

RESUMO

Electromagnetic field (EMF) exposures affect many biological systems. The reproducibility of these effects is related to the intensity, duration, frequency, and pattern of the EMF. We have shown that exposure to a specific time-varying EMF can inhibit the growth of malignant cells. Thomas-EMF is a low-intensity, frequency-modulated (25-6 Hz) EMF pattern. Daily, 1 h, exposures to Thomas-EMF inhibited the growth of malignant cell lines including B16-BL6, MDA-MB-231, MCF-7, and HeLa cells but did not affect the growth of non-malignant cells. Thomas-EMF also inhibited B16-BL6 cell proliferation in vivo. B16-BL6 cells implanted in syngeneic C57b mice and exposed daily to Thomas-EMF produced smaller tumours than in sham-treated controls. In vitro studies showed that exposure of malignant cells to Thomas-EMF for > 15 min promoted Ca(2+) influx which could be blocked by inhibitors of voltage-gated T-type Ca(2+) channels. Blocking Ca(2+) uptake also blocked Thomas-EMF-dependent inhibition of cell proliferation. Exposure to Thomas-EMF delayed cell cycle progression and altered cyclin expression consistent with the decrease in cell proliferation. Non-malignant cells did not show any EMF-dependent changes in Ca(2+) influx or cell growth. These data confirm that exposure to a specific EMF pattern can affect cellular processes and that exposure to Thomas-EMF may provide a potential anti-cancer therapy.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Campos Eletromagnéticos , Animais , Apoptose , Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Células HeLa , Humanos , Células MCF-7 , Magnetoterapia , Masculino , Melanoma Experimental/patologia , Melanoma Experimental/radioterapia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Fatores de Tempo , Transplante Homólogo
16.
PLoS One ; 8(4): e61714, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23620783

RESUMO

A tandem sequence composed of weak temporally-patterned magnetic fields was discovered that produced 100% dissolution of planarian in their home environment. After five consecutive days of 6.5 hr exposure to a frequency-modulated magnetic field (0.1 to 2 µT), immediately followed by an additional 6.5 hr exposure on the fifth day, to another complex field (0.5 to 5 µT) with exponentially increasing spectral power 100% of planarian dissolved within 24 hr. Reversal of the sequence of the fields or presentation of only one pattern for the same duration did not produce this effect. Direct video evidence showed expansion (by visual estimation ∼twice normal volume) of the planarian following the first field pattern followed by size reduction (estimated ∼1/2 of normal volume) and death upon activation of the second pattern. The contortions displayed by the planarian during the last field exposure suggest effects on contractile proteins and alterations in the cell membrane's permeability to water.


Assuntos
Campos Magnéticos , Planárias/fisiologia , Animais , Análise Espectral , Fatores de Tempo
17.
Int J Radiat Biol ; 89(5): 384-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23206181

RESUMO

PURPOSE: To discern if physiologically and naturally-patterned electromagnetic fields presented with base frequencies of 7 Hz within the 100 nT range could facilitate regeneration in planarian similar to microTesla, 60 Hz fields. METHODS: In two separate experiments planarian were decapitated and exposed to either 140 or 400 nT peak amplitude-modulated 7 Hz magnetic fields for 6 min once per hour, 8 h per night for 5 days. Daily regeneration rates and movement velocities (cm/min) were measured. RESULTS: The planarian exposed to either intensity magnetic field exhibited faster regeneration of photoreceptors and auricles compared to sham field and reference groups. The magnetic field exposure accommodated 50% of the variance during the faster growth days. CONCLUSIONS: Naturally-patterned, intermittently-presented weaker electromagnetic fields may produce enhanced regeneration rates in flat worms similar to those observed for 60 Hz, higher intensity fields.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Planárias/fisiologia , Planárias/efeitos da radiação , Regeneração/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Movimento/efeitos da radiação , Fatores de Tempo
18.
Neurosci Lett ; 523(2): 131-4, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22750152

RESUMO

Weak (1 µT) physiologically patterned magnetic fields produce changes in behavioral, physiological, and cellular activity. In the present experiments 12 temporal samples of the electroencephalographic anomaly and normal activity of a person (SLH) whose proximity reliably affected the brain activity of others were extracted from QEEG data, digitized, and presented as equivalent magnetic field patterns to B16 mouse melanoma cells. Only two of the patterns, both originating from the primary source (right temporal lobe) of the EEG anomaly reduced the cell growth by one-third compared to the other patterns extracted from his QEEG or sham field exposures. In previous experiments these EEG transients were also associated with marked increases in photon emissions from the right side of SLH's head. The results suggest that the intrinsic complexity of electroencephalographic patterns of some people, when amplified appropriately and applied as computer-generated magnetic fields in the three spatial planes, could diminish cancer cell growth.


Assuntos
Campos Magnéticos , Melanoma Experimental/patologia , Animais , Proliferação de Células , Eletroencefalografia , Humanos , Camundongos , Software , Lobo Temporal/fisiologia , Células Tumorais Cultivadas
19.
J Cancer Res Clin Oncol ; 137(3): 543-50, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20508946

RESUMO

PURPOSE: Inter-individual variations in treatment efficacy may be influenced by polymorphisms in DNA repair genes. We investigated the association of 3 functional polymorphisms in the nucleotide excision repair (NER) pathway with survival outcome of 95 patients with metastatic breast cancer (MBC) treated with DNA-damaging chemotherapy. METHODS: ERCC1 8092 C/A, ERCC2 Asp312Asn and ERCC2 Lys751Gln were determined using Taqman-based genotyping assays. Genotype associations with breast cancer-specific survival (BCSS) and progression-free survival (PFS) were evaluated using Kaplan-Meier estimates and hazard ratios calculated using Cox regression analysis. Tests for trend were conducted by calculating P-values for the HR coefficient in proportional hazards regression models. RESULTS: ERCC2 Lys751Gln was significantly associated with BCSS (median: 24.8 months for AA/AC combined and 14.2 months for CC, HR: 1.9 (95% CI 1.06-3.26)). Median BCSS decreased with increasing number of designated adverse genotypes for the 3 polymorphisms (P (trend) = 0.003). Risk estimates for PFS were nonsignificantly elevated and were significantly elevated for BCSS for patients with 2 (HR = 2.21, 95% CI: 1.04-4.72) or 3 (HR = 6.67, 95% CI: 2.19-20.29) adverse genotypes. In treatment subgroup analysis, risk estimates for BCSS were significantly elevated for patients with 3 adverse genotypes treated with cyclophosphamide, mitoxantrone and vinblastine (HR: 11.9, 95% CI 1.77-79.51) and P (trend) = 0.02 for increasing number of adverse genotypes. Risk of progression was significantly increased for patients with 1 adverse genotype treated with cyclophosphamide, mitoxantrone and carboplatin (HR: 3.5, 95% CI 1.19-10.6) and P (trend) = 0.02 for increasing number of adverse genotypes. CONCLUSION: Polymorphisms in NER pathway may impact survival outcome for patients with MBC following treatment with DNA-damaging chemotherapy. These results provide support for a polygenic pathway approach for assessing the prognostic and predictive potential of polymorphisms in treatment outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Reparo do DNA , Adulto , Neoplasias da Mama/patologia , Dano ao DNA , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Taxa de Sobrevida , Resultado do Tratamento , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adulto Jovem
20.
Brain Res ; 1388: 77-88, 2011 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-21396353

RESUMO

Light flashes delivered to one aggregate of cells evoked increased photon emission in another aggregate of cells maintained in the dark in another room if both aggregates shared the same temporospatial configuration of changing rate, circular magnetic fields. During the presentation of the same shared circumcerebral magnetic fields increases in photon emission occurred beside the heads of human volunteers if others in another room saw light flashes. Both cellular and human photon emissions during the light flashes did not occur when the shared magnetic fields were not present. The summed energy emissions from the dark location during light stimulation to others was about 10(-11) W/m(2) and calculated to be in the order of 10(-20) J per cell which is coupled to membrane function. These results support accumulating data that under specific conditions changes in photon emissions may reflect intercellular and interbrain communications with potential quantum-like properties.


Assuntos
Encéfalo/fisiologia , Comunicação Celular/fisiologia , Campos Eletromagnéticos , Neurônios/fisiologia , Fótons , Adolescente , Adulto , Animais , Células Cultivadas , Humanos , Luz , Camundongos , Estimulação Luminosa , Teoria Quântica , Rotação , Adulto Jovem
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