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1.
Environ Pollut ; 222: 153, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28063714
2.
J Sch Health ; 85(11): 810-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26440823

RESUMO

BACKGROUND: Growing health disparities have a negative impact on young people's educational achievement. Community schools that involve deep relationships with partners across multiple domains address these disparities by providing opportunities and services that promote healthy development of young people, and enable them to graduate from high school ready for college, technical school, on-the-job training, career, and citizenship. METHODS: Results from Milwaukie High School, North Clackamas, OR; Oakland Unified School District, Oakland, CA; and Cincinnati Community Learning Centers, Cincinnati, OH were based on a review of local site documents, web-based information, interviews, and e-mail communication with key local actors. RESULTS: The schools and districts with strong health partnerships reflecting community schools strategy have shown improvements in attendance, academic performance, and increased access to mental, dental, vision, and health supports for their students. CONCLUSIONS: To build deep health-education partnerships and grow community schools, a working leadership and management infrastructure must be in place that uses quality data, focuses on results, and facilitates professional development across sectors. The leadership infrastructure of community school initiatives offers a prototype on which others can build. Moreover, as leaders build cross-sector relationships, a clear definition of what scaling up means is essential for subsequent long-term systemic change.


Assuntos
Relações Comunidade-Instituição , Relações Interinstitucionais , Relações Interprofissionais , Serviços de Saúde Escolar/organização & administração , California , Participação da Comunidade , Escolaridade , Humanos , Entrevistas como Assunto , Liderança , Governo Local , Ohio , Oregon , Administração em Saúde Pública , Instituições Acadêmicas , Estudantes
3.
Electromagn Biol Med ; 34(4): 387-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25152029

RESUMO

Living cells react defensively and start to synthesize stress proteins when exposed to potentially harmful stimuli. Electromagnetic fields (EMF) are among the many different environmental stimuli that initiate stress protein synthesis. Although there is greater energy transfer and heating due to EMF at higher frequencies, there is no greater stress response. The cellular stress response is far more sensitive to EMF than to an increase in temperature. It should be obvious that an EMF safety standard should be based on the more sensitive, natural biological response.


Assuntos
Campos Eletromagnéticos , Segurança do Paciente/normas , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Biologia Celular , DNA/efeitos da radiação , Dano ao DNA , Exposição Ambiental , Saúde Ambiental , Fractais , Humanos , Gestão da Segurança/métodos , Temperatura
5.
Electromagn Biol Med ; 31(4): 243-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22676645

RESUMO

We propose a biologically based measure of EMF radiation to replace the energy-based "specific absorption rate" (SAR). A wide range of EMF frequencies has been linked to an increased risk of cancer. The SAR value used to measure the EMF dose and set the safety standard in the radiofrequency (RF) range fails as a standard for predicting cancer risk in the ELF power frequency range. Because cancers are believed to arise from mutations in DNA, changes in DNA induced by interaction with EMF could be a better measure of the biologically effective dose in both frequency ranges. The changes can be measured by transcriptional alterations and/or translational changes in specific proteins. Because ionizing radiation also causes DNA damage, a biologically based standard related to stimulation of DNA could apply over a much wider range of the electromagnetic spectrum. A safety standard for exposure to a wide range of non ionizing frequencies can be based on the documented changes in DNA biochemistry that arise from interactions with EMF.


Assuntos
DNA/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Saúde , Radiometria/métodos , Absorção , Animais , DNA/genética , Dano ao DNA , Radiometria/normas , Padrões de Referência
6.
New Dir Youth Dev ; 2011(131): 55-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22028080

RESUMO

Community schools expand learning time and opportunities as one important dimension of a comprehensive strategy to ensure that students are ready for college, career, and citizenship.


Assuntos
Currículo , Aprendizagem , Instituições Acadêmicas/classificação , Humanos
7.
Int J Radiat Biol ; 87(4): 409-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21457072

RESUMO

PURPOSE: To review the responses of deoxyribonucleic acid (DNA) to electromagnetic fields (EMF) in different frequency ranges, and characterise the properties of DNA as an antenna. MATERIALS AND METHODS: We examined published reports of increased stress protein levels and DNA strand breaks due to EMF interactions, both of which are indicative of DNA damage. We also considered antenna properties such as electronic conduction within DNA and its compact structure in the nucleus. RESULTS: EMF interactions with DNA are similar over a range of non-ionising frequencies, i.e., extremely low frequency (ELF) and radio frequency (RF) ranges. There are similar effects in the ionising range, but the reactions are more complex. CONCLUSIONS: The wide frequency range of interaction with EMF is the functional characteristic of a fractal antenna, and DNA appears to possess the two structural characteristics of fractal antennas, electronic conduction and self symmetry. These properties contribute to greater reactivity of DNA with EMF in the environment, and the DNA damage could account for increases in cancer epidemiology, as well as variations in the rate of chemical evolution in early geologic history.


Assuntos
Dano ao DNA , DNA/química , DNA/efeitos da radiação , Modelos Químicos , DNA/genética , Campos Eletromagnéticos , Fractais , Modelos Genéticos , Doses de Radiação
8.
Inflamm Bowel Dis ; 16(9): 1505-13, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20803697

RESUMO

BACKGROUND: Migration of colonic lamina propria fibroblasts (CLPF) is an important mechanism during wound healing in inflammatory bowel disease (IBD). The concentration of prostaglandin E2 (PGE2) is increased in the intestinal mucosa of IBD patients. We therefore investigated the role of PGE2 in CLPF migration. METHODS: Primary cultures of CLPF were isolated from healthy controls and Crohn's disease patients. Migration assays were performed in the Boyden chamber and scratch assays. EP receptors, PGE2, intracellular cyclic adenosine monophosphate (cAMP), expression and distribution of F-actin, alpha-smooth muscle actin (SMA), and myosin light chain (MLC) were determined by immunoblotting, immunocytochemistry, and enzyme-linked immunosorbent assay (ELISA). RESULTS: All four EP receptor subtypes were present on CLPF. PGE2 and agonists to the EP2 and EP4 receptor reduced the migration of CLPF. Blockade of the EP2 and the EP4 receptor inhibited the effect of PGE2 on CLPF migration. An increase in intracellular cAMP reduced CLPF migration. PGE2 increased the concentrations of cAMP in CLPF, with abrogation after addition of EP2 and EP4 receptor antagonists. PGE2 and forskolin decreased the expression of alpha-SMA and F-actin and reduced cell polarization and lamellipodium formation in a scratch assay. In addition, forskolin reduced the phosphorylation of MLC (pMLC) and led to lack of accumulation of pMLC in the leading edge of CLPF. CONCLUSIONS: PGE2 reduced the migration of CLPF via elevation of intracellular cAMP. Potential mechanisms are changes in expression of cytoskeletal proteins, failure of CLPF to polarize, and a decreased amount of pMLC. This might be a possible reason for the impairment of intestinal wound healing in IBD.


Assuntos
Movimento Celular/efeitos dos fármacos , Colo/citologia , Colo/efeitos dos fármacos , Dinoprostona/farmacologia , Fibroblastos/citologia , Mucosa/citologia , Ocitócicos/farmacologia , Western Blotting , Células Cultivadas , Colo/metabolismo , AMP Cíclico/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Humanos , Mucosa/efeitos dos fármacos , Mucosa/metabolismo , Receptores de Prostaglandina E Subtipo EP1/metabolismo , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Cicatrização/efeitos dos fármacos
9.
Int J Radiat Biol ; 85(10): 851-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19639507

RESUMO

PURPOSE: To use regenerating Planaria Dugesia dorotocethala as a model to determine whether an intermittent modulated extremely low frequency electro-magnetic field (ELF-EMF) produces elevated levels of the heat shock protein hsp70 and stimulates intracellular pathways known to be involved in injury and repair. We focused on serum response element (SRE) binding through the extra-cellular signal-regulated kinase (ERK) cascade. MATERIALS AND METHODS: Planaria were transected equidistant between the tip of the head and the tip of the tail. Individual head and tail portions from the same worm were exposed to a 60 Hertz 80 milliGauss ELF-EMF for 1 h twice daily for 15 days post-transection under carefully controlled exposure conditions. The regenerating heads and tails were photographed and the lengths measured at three-day intervals. In other experiments, the timing of the appearance of pigmented eyes was monitored in the tail portion at 12-h intervals following transection in both ELF-EMF exposed and sham control. In some experiments protein lysates were analysed for hsp70 levels, doubly phosphorylated (pp)-ERK, Elk-1 kinase activity and serum response factor (SRF)-SRE binding. RESULTS: ELF-EMF exposure during the initial 3-days post-surgery caused a significant increase in regeneration for both heads and tails, but especially tails. The first appearance of eyes occurred at day seven post-transection in tail portions exposed to ELF-EMF. In the sham control tail samples the initial appearance of eyes occurred 48 h later. Concurrently, ELF-EMF-exposed heads and tails exhibited an elevation in the level of hsp70 protein, an activation of an ERK cascade, and an increase in SRF-SRE binding. CONCLUSION: Exposures to a modulated sinusoidal ELF-EMF were delivered by a Helmholtz configuration at a frequency of 60 Hz and 80 mG twice a day for one hour. This is accompanied by an increase in hsp70 protein levels, activation of specific kinases and upregulation of transcription factors that are generally associated with repair processes.


Assuntos
Campos Eletromagnéticos , Proteínas de Choque Térmico HSP70/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Planárias/fisiologia , Planárias/efeitos da radiação , Regeneração/efeitos da radiação , Animais , Fatores de Tempo
10.
Pathophysiology ; 16(2-3): 67-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19264462
11.
Pathophysiology ; 16(2-3): 71-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19268550

RESUMO

Electromagnetic fields (EMF), in both ELF (extremely low frequency) and radio frequency (RF) ranges, activate the cellular stress response, a protective mechanism that induces the expression of stress response genes, e.g., HSP70, and increased levels of stress proteins, e.g., hsp70. The 20 different stress protein families are evolutionarily conserved and act as 'chaperones' in the cell when they 'help' repair and refold damaged proteins and transport them across cell membranes. Induction of the stress response involves activation of DNA, and despite the large difference in energy between ELF and RF, the same cellular pathways respond in both frequency ranges. Specific DNA sequences on the promoter of the HSP70 stress gene are responsive to EMF, and studies with model biochemical systems suggest that EMF could interact directly with electrons in DNA. While low energy EMF interacts with DNA to induce the stress response, increasing EMF energy in the RF range can lead to breaks in DNA strands. It is clear that in order to protect living cells, EMF safety limits must be changed from the current thermal standard, based on energy, to one based on biological responses that occur long before the threshold for thermal changes.

12.
J Cell Physiol ; 216(3): 816-23, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18446816

RESUMO

Studies on myocardial function have shown that hsp70, stimulated by an increase in temperature, leads to improved survival following ischemia-reperfusion (I-R). Low frequency electromagnetic fields (EMFs) also induce the stress protein hsp70, but without elevating temperature. We have examined the hemodynamic changes in concert with EMF pre-conditioning and the induction of hsp70 to determine whether improved myocardial function occurs following I-R injury in Sprague-Dawley rats. Animals were exposed to EMF (60 Hz, 8 microT) for 30 min prior to I-R. Ischemia was then induced by ligation of left anterior descending coronary artery (LAD) for 30 min, followed by 30 min of reperfusion. Blood and heart tissue levels for hsp70 were determined by Western blot and RNA transcription by rtPCR. Significant upregulation of the HSP70 gene and increased hsp70 levels were measured in response to EMF pre-exposures. Invasive hemodynamics, as measured using a volume conductance catheter, demonstrated significant recovery of systolic contractile function after 30 min of reperfusion following EMF exposure. Additionally, isovolemic relaxation, a measure of ventricular diastolic function, was markedly improved in EMF-treated animals. In conclusion, non-invasive EMF induction of hsp70 preserved myocardial function and has the potential to improve tolerance to ischemic injury.


Assuntos
Campos Eletromagnéticos , Proteínas de Choque Térmico HSP70/metabolismo , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Idoso , Animais , Feminino , Proteínas de Choque Térmico HSP70/genética , Hemodinâmica , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão
13.
Electromagn Biol Med ; 27(1): 3-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18327711

RESUMO

The stimulation of protein and DNA by electromagnetic fields (EMF) has been problematic because the fields do not appear to have sufficient energy to directly affect such large molecules. Studies with electric and magnetic fields in the extremely low-frequency range have shown that weak fields can cause charge movement. It has also been known for some time that redistribution of charges in large molecules can trigger conformational changes that are driven by large hydration energies. This review considers examples of direct effects of electric and magnetic fields on charge transfer, and structural changes driven by such changes. Conformational changes that arise from alterations in charge distribution play a key role in membrane transport proteins, including ion channels, and probably account for DNA stimulation to initiate protein synthesis. It appears likely that weak EMF can control and amplify biological processes through their effects on charge distribution.


Assuntos
DNA/metabolismo , Campos Eletromagnéticos , Proteínas/metabolismo , Membrana Celular/metabolismo , Hemoglobinas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo
14.
J Cell Physiol ; 214(1): 20-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17620313

RESUMO

Electrons have been shown to move in DNA, and a specific DNA sequence is associated with the response to EM fields. In addition, there is evidence from biochemical reactions that EM fields can accelerate electron transfer. Interaction with electrons could displace electrons in H-bonds that hold DNA together leading to chain separation and initiating transcription. The effect of charging due to electron displacement on the energetics of DNA aggregation shows that electron transfer would favor separation of base pairs, and that DNA geometry is optimized for disaggregation under such conditions. Electrons in the H-bonds of both DNA and the surrounding water molecules fluctuate at frequencies that are much higher than the frequencies of the EM fields studied. The characteristics of the fluctuations suggest that the applied EM fields are effectively DC pulses and that interactions extend to microwave frequencies.


Assuntos
Pareamento de Bases/genética , Bioquímica , DNA/efeitos da radiação , Campos Eletromagnéticos , Transcrição Gênica/efeitos da radiação , Animais , Fenômenos Bioquímicos , DNA/química , Elétrons , Humanos , Ligação de Hidrogênio/efeitos da radiação , Transdução de Sinais , Água/química
16.
Electromagn Biol Med ; 25(4): 203-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17178580

RESUMO

Regulatory action based on the Precautionary Principle is generally guided by the results of epidemiology studies. Even though laboratory research on electromagnetic fields (EMF) has supplied much relevant information and continues to do so, it is often overlooked. Laboratory research has shown that EMF of many frequencies stimulate many biological systems, and at low thresholds of both field strength and duration. It has also shown that EMF stimulate protein synthesis in cells and accelerate electron transfer reactions. In the last few years, important practical insights have been provided by the research on the cellular stress response, where the same specific biological response is induced in cells by both ELF (power frequency) and RF (radio frequency) fields, despite the very different energy levels. Since this protective biological response is not determined by the level of energy absorbed, safety standards based on the best available biological evidence must (1) recognize non thermal protective responses and (2) include cumulative exposures across the EM spectrum.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Saúde Ambiental , Medicina Preventiva , Saúde Pública , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Medição de Risco/métodos , DNA/efeitos da radiação , Meio Ambiente , Exposição Ambiental , Humanos , Prevenção Primária , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Ondas de Rádio , Pesquisa , Medição de Risco/normas , Gestão da Segurança/métodos , Gestão da Segurança/normas
17.
Bioelectromagnetics ; 26(8): 677-83, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16189824

RESUMO

The effects of low frequency electric and magnetic fields on several biochemical systems, including the Na,K-ATPase, indicate that electromagnetic (EM) fields interact with electrons. The frequency optima for two enzymes in response to EM fields are very close to their turnover numbers, suggesting that these interactions directly affect reaction rates. Nevertheless, generally accepted ideas about Na,K-ATPase function and ion transport mechanisms do not consider interactions with electrons. To resolve the clash of paradigms, we hypothesize interaction with transient electrons and protons that arise from flickering of H-bonds in the hydrated protein. These transient charges in the enzyme could provide a trigger for the sequence of conformation changes that are part of the ion transport mechanism. If the distributions of transient electrons and protons in the membrane are affected by their concentration and the membrane potential, as expected from electric double layer theory, this can account for the different effects of low frequency electric and magnetic fields, as well as for the observation that membrane hyperpolarization reverses the ATPase reaction to generate ATP.


Assuntos
Campos Eletromagnéticos , Elétrons , ATPase Trocadora de Sódio-Potássio/química , Ligação de Hidrogênio , Potenciais da Membrana , Conformação Proteica
18.
Bioelectromagnetics ; 25(8): 642-6; discussion 647-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15515027

RESUMO

Questions of safety of electromagnetic (EM) fields should be based on relevant biological properties, i.e., specific cellular reactions to potentially harmful stimuli. The stress response is a well documented protective reaction of plant and animal cells to a variety of environmental threats, and it is stimulated by both extremely low frequency (ELF) and radio frequency (RF) EM fields. It involves activation of DNA to initiate synthesis of stress proteins. Thermal and non-thermal stimuli affect different segments of DNA and utilize different biochemical pathways. However, both ELF and RF stimulate the same non-thermal pathway. Since the same biochemical reactions are stimulated in different frequency ranges with very different specific absorption rates (SARs), SAR level is not a valid basis for safety standards. Studies of EM field interactions with DNA and with model systems provide insight into a plausible mechanism that can be effective in ELF and RF ranges.


Assuntos
Campos Eletromagnéticos , Guias como Assunto , Estresse Oxidativo/efeitos da radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Medição de Risco/métodos , Doses de Radiação , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Medição de Risco/normas , Fatores de Risco , Gestão da Segurança/métodos , Gestão da Segurança/normas
19.
J Cell Physiol ; 199(3): 359-63, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15095282

RESUMO

Low frequency electromagnetic (EM) fields induce gene expression, and recent insights into physical interactions of EM fields with model systems suggest a mechanism that could initiate this process. The consistently low thresholds at which EM fields stimulate biological processes indicate that they require little energy. Since it has been shown that such weak fields accelerate electron transfer reactions, they could stimulate transcription by interacting with electrons in DNA to destabilize the H-bonds holding the two DNA strands together. Such a mechanism is consistent with the low electron affinity of the bases in previously identified electromagnetic response elements (EMREs) needed for EM field interaction with DNA. It is also in line with both endogenous and in vitro stimulation of biosynthesis by electric fields. The frequency response of several EM sensitive biological systems suggests that EM fields require repetition and are most effective at frequencies that coincide with natural rhythms of the processes affected.


Assuntos
DNA/efeitos da radiação , Campos Eletromagnéticos , Transcrição Gênica/efeitos da radiação , Animais , Elétrons , Humanos , Ligação de Hidrogênio/efeitos da radiação
20.
Bioelectrochemistry ; 61(1-2): 93-7, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14642914

RESUMO

Acceleration of the Belousov-Zhabotinski (BZ) reaction, in stirred homogeneous solutions, by low frequency electromagnetic (EM) fields has provided new insights into EM interaction mechanisms. The acceleration varies inversely with the basal reaction rate, indicating that the applied magnetic field and the intrinsic chemical driving forces affect the same electron transfer reaction. The amplitude and frequency dependence of the EM field interactions are also consistent with interaction during electron transfer. A mechanism based on interaction with moving electrons offers a way of explaining the ability of EM fields to stimulate gene expression, in particular the stress response, since electrons have been shown to move in DNA.


Assuntos
DNA/química , Campos Eletromagnéticos , Transporte de Elétrons/efeitos da radiação , Bromatos/química , Bromo/química , Catálise , DNA/efeitos da radiação , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Expressão Gênica/efeitos da radiação , Proteínas de Choque Térmico/biossíntese , Ferro/química , Cinética , Malonatos/química , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo
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