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BACKGROUND: Extremely low frequency (ELF) electromagnetic fields (EMF) are known to produce a variety of biological effects. Clinical studies are ongoing using EMF in healing of bone fractures and skin wounds. However, little is known about the mechanisms of action of ELF-EMF. Several studies have demonstrated that expression and regulation of nitric oxide synthase (NOS) and cyclooxygenase-2 (COX-2) are vital for wound healing; however, no reports have demonstrated a direct action of ELF-EMF in the modulation of these inflammatory molecules in human keratinocytes. OBJECTIVES: The present study analysed the effect of ELF-EMF on the human keratinocyte cell line HaCaT in order to assess the mechanisms of action of ELF-EMF and to provide further support for their therapeutic use in wound healing. METHODS: Exposed HaCaT cells were compared with unexposed control cells. At different exposure times, expression of inducible NOS (iNOS), endothelial NOS (eNOS) and COX-2 was evaluated by Western blot analysis. Modulation of iNOS and eNOS was monitored by evaluation of NOS activities, production of nitric oxide (NO) and O(2)(-) and expression of activator protein 1 (AP-1). In addition, catalase activity and prostaglandin (PG) E(2) production were determined. Effects of ELF-EMF on cell growth and viability were monitored. RESULTS: The exposure of HaCaT cells to ELF-EMF increased iNOS and eNOS expression levels. These ELF-EMF-dependent increased expression levels were paralled by increased NOS activities, and increased NO production. In addition, higher levels of AP-1 expression as well as a higher cell proliferation rate were associated with ELF-EMF exposure. In contrast, ELF-EMF decreased COX-2 expression, PGE(2) production, catalase activity and O(2)(-) production. CONCLUSIONS: Mediators of inflammation, such as reactive nitrogen and PGE(2), and keratinocyte proliferation are critical for the tissue regenerative processes. The ability of ELF-EMF to upmodulate NOS activities, thus nitrogen intermediates, as well as cell proliferation, and to downregulate COX-2 expression and the downstream intermediate PGE(2), highlights the potential therapeutic role of ELF-EMF in wound healing processes.
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Ciclo-Oxigenase 2/metabolismo , Queratinócitos/metabolismo , Magnetoterapia/métodos , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Cicatrização , Linhagem Celular , Proliferação de Células , Campos Eletromagnéticos , HumanosRESUMO
BACKGROUND: Proliferation and differentiation of keratinocytes are central processes in tissue regeneration after injury. Chemokines, produced by a wide range of cell types including keratinocytes, play a regulatory role in inflammatory skin diseases. Several studies have shown that an electromagnetic field (EMF) can influence both inflammatory processes and repair mechanisms including wound healing on different tissue models. OBJECTIVES: To elucidate the effect of extremely low frequency EMF (ELF-EMF) on keratinocyte proliferation and production of chemokines [RANTES, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1 alpha and interleukin (IL)-8] in order to evaluate a potential therapeutic use of magnetic fields. METHODS: The human keratinocyte cell line HaCaT was exposed at 1 mT, 50 Hz for different lengths of time and compared with unexposed control cells. Cell growth and viability were evaluated at different exposure times by cell count and trypan blue exclusion. Chemokine production and expression were analysed by enzyme-linked immunosorbent assay (ELISA) and by real-time polymerase chain reaction. Total NF-kappaB p65 was quantified by ELISA. RESULTS: Significantly increased growth rates were observed after 48 h of EMF exposure as compared with control cells, while no difference in cell viabilities were detected. Gene expression and release of RANTES, MCP-1, MIP-1 alpha and IL-8 were significantly reduced after 72 h of exposure. NF-kappaB levels became almost undetectable after only 1 h of EMF exposure, and were inversely correlated with cell density. CONCLUSIONS: Our results show that ELF-EMF modulates chemokine production and keratinocyte growth through inhibition of the NF-kappaB signalling pathway and thus may inhibit inflammatory processes. ELF-EMF could represent an additional therapeutic approach in the treatment of skin injury.
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Proliferação de Células/efeitos da radiação , Quimiocinas/metabolismo , Dermatite/radioterapia , Campos Eletromagnéticos , Queratinócitos/efeitos da radiação , Quimiocina CCL5/metabolismo , Quimiocinas/efeitos da radiação , Relação Dose-Resposta à Radiação , Ensaio de Imunoadsorção Enzimática/métodos , Expressão Gênica , Humanos , Interleucina-8/metabolismo , Interleucina-8/efeitos da radiação , Queratinócitos/metabolismo , NF-kappa B/metabolismo , NF-kappa B/efeitos da radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Resultado do Tratamento , CicatrizaçãoRESUMO
In technologically developed countries, there is concern about hazards from electromagnetic fields (EMFs). Several studies have reported that immune and neuroendocrine systems exert an integrated response to EMF exposure. The aim of this review is to summarize the results of studies on the effect of low and high frequency EMF on immune and neuroendocrine systems on which our research group has been working for several years.
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Campos Eletromagnéticos/efeitos adversos , Neuroimunomodulação , Animais , Feminino , Humanos , Técnicas In Vitro , Células Matadoras Naturais/imunologia , Masculino , Camundongos , Sistemas Neurossecretores , Ratos , Linfócitos T Citotóxicos/imunologiaRESUMO
Quantitative proton magnetic resonance spectroscopy (MRS) was used to determine region-specific metabolic changes in young and aged animals subjected to a long-term hypoxic-ischemic injury. Focal ischemia, which was studied as an experimental stroke model, was induced in 3- and 24-month-old rats by unilateral common carotid artery occlusion associated with 24 h of hypoxia. Eight metabolites were quantified from extracts in three different brain regions (hippocampus, frontoparietal and occipital cortices) from both the ipsilateral and contralateral sides. Our findings showed significant differences in lactate and myo-inositol concentration values in the hippocampus of the aged rats as compared to the same area of the young adult group under normoxic conditions. After hypoxia-ischemia (HI), the most relevant changes in metabolite concentrations were found in the hippocampal region of both young and aged groups as compared to their age-matched controls. Of the three brain areas under investigation, the hippocampus proved to be particularly susceptible to the prolonged hypoxia-ischemia perturbation. The effects were more evident in the aged animals.
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Envelhecimento/metabolismo , Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Neurotransmissores/metabolismo , Fatores Etários , Animais , Química Encefálica , Doença Crônica , Feminino , Neurotransmissores/análise , Prótons , Ratos , Ratos Wistar , Fatores de Tempo , Distribuição TecidualRESUMO
The greatest impediment to extracting high-quality fetal signals from fetal magnetocardiography (fMCG) is environmental magnetic noise, which may have peak-to-peak intensity comparable to fetal QRS amplitude. Being an unstructured Gaussian signal with large disturbances at specific frequencies, ambient field noise can be reduced with hardware-based approaches and/or with software algorithms that digitally filter magnetocardiographic recordings. At present, no systematic evaluation of filters' performances on shielded and unshielded fMCG is available. We designed high-pass and low-pass Chebychev II-type filters with zero-phase and stable impulse response; the most commonly used band-pass filters were implemented combining high-pass and low-pass filters. The achieved ambient noise reduction in shielded and unshielded recordings was quantified, and the corresponding signal-to-noise ratio (SNR) and signal-to-distortion ratio (SDR) of the retrieved fetal signals was evaluated. The study regarded 66 fMCG datasets at different gestational ages (22-37 weeks). Since the spectral structures of shielded and unshielded magnetic noise were very similar, we concluded that the same filter setting might be applied to both conditions. Band-pass filters (1.0-100 Hz) and (2.0-100 Hz) provided the best combinations of fetal signal detection rates, SNR and SDR; however, the former should be preferred in the case of arrhythmic fetuses, which might present spectral components below 2 Hz.
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Coração Fetal/patologia , Monitorização Fetal/métodos , Magnetoencefalografia/instrumentação , Magnetoencefalografia/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Arritmias Cardíacas , Idade Gestacional , Frequência Cardíaca Fetal , Humanos , Magnetismo , Modelos Estatísticos , Distribuição Normal , Reconhecimento Automatizado de Padrão , Diagnóstico Pré-Natal , SoftwareRESUMO
Fetal magnetocardiography (fMCG) provides fetal cardiac traces useful for the prenatal monitoring of fetal heart function. In this paper, we describe an analytical model (ACWD) for the automatic detection of cardiac waves boundaries that works on fetal signals reconstructed from fMCG by means of independent component analysis. ACWD was validated for 45 healthy and 4 arrhythmic fetuses ranging from 22 to 37 weeks; ACWD outcomes were compared with the estimates of three independent investigators. Descriptive statistics were used to assess correspondence between the outcomes of the automatic and manual approaches. The parametric two-tailed Pearson correlation test (alpha=0.01) was employed to quantify, by means of the coefficients of determination, the amount of common variation between the sequences of intervals quantified automatically and manually. ACWD performances on short and long rhythm strips were investigated. ACWD demonstrated to be a robust tool providing dependable estimates of cardiac intervals and their variability during the third gestational trimester also in case of fetal arrhythmias. SNR and stability of fetal traces were the factors limiting ACWD performances. ACWD computation time, which was approximately 1:600 with respect to the manual procedure, was comparable with the time required for fCTI estimation on averaged beats.
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Algoritmos , Arritmias Cardíacas/diagnóstico , Cardiotocografia/métodos , Diagnóstico por Computador/métodos , Eletrocardiografia/métodos , Magnetismo , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador , Feminino , Humanos , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVES: This paper describes an integrated software suite (ISS) for the processing of magnetocardiographic (MCG) recordings obtained with super-conducting multi-channel systems having different characteristics. We aimed to develop a highly flexible suite including toolboxes for current MCG applications, organized consistently with an open architecture that allows function integrations and upgrades with minimal modifications; the suite was designed for the compliance not only of physicists and engineers but also of physicians, who have a different professional profile and are accustomed to retrieve information in different ways. METHODS: The MCG-ISS was designed to work with all common graphical user interface operative systems. MATLAB was chosen as the interactive programming environment (IPE), and the software was developed to achieve usability, interactivity, reliability, modularity, expansibility, interoperability, adaptability and graphics style tailoring. Three users, already experienced in MCG data analysis, have intensively tested MCG-ISS for six months. A great amount of MCG data on normal subjects and patients was used to assess software performances in terms of user compliance and confidence and total analysis time. RESULTS: The proposed suite is an all-in-one analysis tool that succeeded in speeding MCG data analysis up to about 55% with respect to standard reference routines; it consequently enhanced analysis performance and user compliance. CONCLUSIONS: Those results, together with the MCG-ISS advantage of being independent on the acquisition system, suggest that software suites like the proposed one could uphold a wider diffusion of MCG as a diagnostic tool in the clinical setting.
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Eletrocardiografia/métodos , Coração , Software , Estatística como Assunto , Diagnóstico por Computador , Coração/fisiologia , Humanos , Itália , Linguagens de ProgramaçãoRESUMO
M-mode and pulsed Doppler echocardiography, cardiotocography and transabdominal fetal ECG are available in clinical practice to monitor fetal cardiac activity during advancing gestation, but none of these methods allows the direct measurement of morphological and temporal parameters for fetal rhythm assessment. Fetal magnetocardiograms (fMCGs) are noninvasive recordings of magnetic field variations associated with electrical activity of the fetal heart obtained with superconducting sensors positioned over the maternal abdomen inside a shielded room. Because of maternal cardiac activity, fMCGs are contaminated by maternal components that need to be eliminated to reconstruct fetal cardiac traces. The aim of the present work was to use two methods working in the time domain, an independent component analysis algorithm (FastICA) and an adaptive maternal beat subtraction technique (AMBS), for the retrieval of fetal cardiac signals from fMCGs. Detection rates of both methods were calculated, and FastICA and AMBS performances were compared in the context of clinical applications by estimating several temporal and morphological characteristics of the retrieved fetal traces, such as the shape and duration P-QRS-T waves, arrhythmic beat detection and classification, and noise reduction. Quantitative and qualitative comparison produced figures that always suggested that FastICA was superior to AMBS from the perspective of clinical use of the recovered fetal signals.
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Algoritmos , Arritmias Cardíacas/diagnóstico , Campos Eletromagnéticos , Frequência Cardíaca Fetal , Diagnóstico Pré-Natal , Adulto , Artefatos , Eletrofisiologia , Feminino , Humanos , Gravidez , Processamento de Sinais Assistido por ComputadorRESUMO
Fetal magnetocardiography (fMCG) is the only noninvasive technique allowing effective assessment of fetal cardiac electrical activity during the prenatal period. The reconstruction of reliable magnetic field mapping associated with fetal heart activity would allow three-dimensional source localization. The efficiency of independent component analysis (ICA) in restoring reliable fetal traces from multichannel fMCG has already been demonstrated. In this paper, we describe a method of reconstructing a complete set of fetal signals hidden in multichannel fMCG preserving their correct spatial distribution, waveform, polarity and amplitude. Fetal independent components, retrieved with an ICA algorithm (FastICA), were interpolated (fICI method) using information gathered during FastICA iterations. The restored fetal signals were used to reconstruct accurate magnetic mapping for every millisecond during the average beat. The procedure was validated on fMCG recorded from the 22nd gestational week onward with a multichannel MCG system working in a shielded room. The interpolated traces were compared with those obtained with a standard technique, and the consistency of fetal mapping was checked evaluating source localizations relative to fetal echocardiographic information. Good magnetic field distributions during the P-QRS-T waves were attained with fICI for all gestational periods; their reliability was confirmed by three-dimensional source localizations.
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Algoritmos , Mapeamento Potencial de Superfície Corporal/métodos , Cardiotocografia/métodos , Diagnóstico por Computador/métodos , Frequência Cardíaca Fetal , Magnetismo , Processamento de Sinais Assistido por Computador , Eletrocardiografia/métodos , Feminino , Humanos , Gravidez , Análise de Componente Principal , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Nowadays, concerns about hazards from electromagnetic fields represent an alarming source for human lives in technologically developed countries. We are surrounded by electromagnetic fields everywhere we spend our working hours, rest or recreational activities. The aim of this review is to summarize the biological effects due to these fields arising from power and transmission lines, electrical cable splices, electronic devices inside our homes and work-places, distribution networks and associated devices such as cellular telephones and wireless communication tower, etc. Special care has been reserved to study the biological effects of electromagnetic fields on cell lines of the mammalian immune system about which our research group has been working for several years.
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A non-invasive, innovative approach to the study of Raynaud's Phenomenon is proposed. A group of patients, with respect of a control group, underwent a simultaneous assessment of thermal properties of all ten fingers using infrared functional imaging (IRFI). The assessment highlighted a quite different behaviour between patients with Primary- (PRP) and those with scleroderma - Raynaud's Phenomenon (SSc) and, compared with other existing techniques, seems to be an objective and effective tool to discriminate between PRP and RP secondary to SSc. 18 healthy volunteers (Norm), 20 Primary Raynaud's Phenomenon (PRP) and 20 Secondary Scleroderma (SSc) patients were studied subsequently to clinical evaluation and nail fold capillaroscopy. High-resolution infrared imaging of finger re-warming processes, immediately after a 2 min cold stress, allowed to identify objective parameters. Temperature integral Q (the temperature evaluation of the area under the time-temperature curve along the re-warming period) provided particularly effective figures in describing thermal properties of the fingers. Grand average Q values were (383.4 ∓ 12.5) °C×min, (502.9 ± 88.1) °C×min and (1022.0 ± 110.2) °C×min for the PRP, SSc and Normal groups, respectively. Separate evaluation of the temperature integral for each finger leads to very similar results for the fingers of all the PRP patients; a different thermoregulatory response was observed in SSc patients. The sensitivity of the method in order to distinguish healthy from ill fingers was 100%. The specificity in distinguishing SSc from PRP was 95%. In addition, IRFI parameters provided a better understanding of the impaired control of the finger's temperature in PRP and SSc with respect to the Normal group. This pilot study also applied IRFI for the measurement of drug effects in patients with Raynaud's Phenomenon. Sixteen out of twenty SSc patients were tested in a single 1-hour session of N-acetylcysteine infusion. IRFI clearly documented a significant increase of face and hands temperature during the drug administration. The grand average value of the finger's temperature after the 1 hour NAC administration was (29.6 ± 3.7) °C, while its value before was (27.9 ± 3.7) °C (p<0.001). N-acetylcysteine seems to act as a vasodilator in patients with Raynaud's phenomenon secondary to systemic sclerosis (scleroderma).
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The objective of this study was to validate a real-time 3-dimensional echocardiography (3DE) technique for the determination of left ventricular (LV) volume and ejection fraction (EF). In 10 mongrel dogs, an electromagnetic flow (EMF) probe was placed on the aorta, and the thorax was closed. Transthoracic imaging was performed during multiple hemodynamic conditions (n = 58) with simultaneous measurement of stroke volume (SV) with the use of EMF. From the volumetric data set, LV volumes were manually traced off-line by 2 independent observers with an apical rotation method (6 planes) and a conventional method (biplane) in a subset of conditions. This tracing technique was also evaluated in 18 human subjects in whom the calculated EF values were compared with values derived by multigated radionuclide angiography (MUGA). Excellent correlation and close limits of agreement were noted between SV measured by 3DE and EMF (r = 0.93) in dogs. In comparison with EMF-derived SV, 3DE provided better correlation than the biplane method (r = 0.93 versus r = 0.61). Interobserver and intraobserver variabilities were comparable (r = 0.94 and r = 0.94, respectively). In a comparison of MUGA-derived EF values and those obtained by 3DE in human subjects, 3DE provided better correlation than the biplane method (r = 0.94 versus r = 0.85). Real-time 3DE accurately measures left ventricular volumes transthoracically over a wide range of hemodynamic conditions in dogs and accurately determines EF in humans.
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Ecocardiografia Tridimensional/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Animais , Cães , Estudos de Viabilidade , Imagem do Acúmulo Cardíaco de Comporta , Hemodinâmica , Humanos , Modelos Lineares , Volume Sistólico , Fatores de Tempo , Função Ventricular EsquerdaRESUMO
Extremely low frequency electromagnetic fields (ELF-EMF) induce cellular changes and modulate signal transduction pathways, and may be beneficial in the treatment of inflammatory diseases. In this paper we studied two inflammatory chemokines, MCP-1 and RANTES produced by human cultured isolated monocytes from peripheral blood, with or without PHA and in the absence or presence of 50 Hz magnetic field of 1.0 mT for 24 h. The production of MCP-1 and RANTES was determined by ELISA method. Here, we found that ELF-EMF strongly inhibited the production of these chemokines stimulated by PHA, while the control was not affected. Since MCP-1 and RANTES exert chemoattraction for several populations inflammatory leukocytes, the inhibitory effect of these chemokines could be one of the mechanisms by which ELF-EMF is therapeutic in inflammatory diseases.
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Sera of 489 children from Northern Greece aged between 6 months and 15 years of age and aflicted with different clinical entities, were tested for anti Leishmania infantum specific IgG and IgM antibodies, using an ELISA (enzyme linked immunosorbent assay) technique. In this survey, a remarkably high percentage (8.5%) of hospitalized children reacted positively to this method. Twenty three out of 489 children (4.7%) had IgG antibodies, seventeen (3.5%) IgM, while two (0.4%) had both IgG and IgM antibodies against soluble antigen of L. infantum promastigotes. Females had a higher seropositivity than males. The highest prevalence was observed in males aged between 6 months and 5 years old (10 out of 19), while the lowest was observed also in males aged between 11 and 15 years old (5 out of 11). Seropositivity rate was higher in children below 5 years of age. Some epidemiologic, as well as clinical data of canine Leishmaniosis from Northern Greece are discussed.
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Carcinoid syndrome originates from metastatic carcinoid tumors localized in the gastrointestinal system, pancreas, biliary vessels, bronchi, ovaries, and testes; it is characterized by flushing, telangiectasias, diarrhea, bronchoconstriction, and fibrous endocardial plaques in the heart. Cardiac involvement is detected by echocardiography in over 50% of patients with this syndrome. Right-sided valvular heart disease occurs frequently in patients with carcinoid syndrome, involving most commonly the tricuspid and pulmonary valves. Involvement of the left-sided valves rarely occurs. Medical therapy for carcinoid heart disease includes digitalis and diuretics for congestive heart failure symptoms; the effects of carcinoid syndrome can be treated with the use of somatostatin analogues. Conventional chemotherapy has been of little beneficial value, with response rates of only 10% to 30%. The use of octreotide, a long-acting and potent somatostatin analogue, is a major advance in the management of carcinoid tumors. In addition to providing effective symptom relief in malignant carcinoid syndrome, octreotide can also be used for diagnostic purposes. Despite its expense, octreotide is the current agent of choice for the treatment of this condition. Analogues with different receptor specificities and pharmacokinetics hold promise for the future. Valve surgery is the only definitive treatment for intractable right-sided heart failure. Although cardiac surgery carries high perioperative mortality, marked symptomatic improvement occurs in survivors. Surgical intervention therefore should be considered in the appropriate patients when cardiac symptoms become severe. Balloon valvulotomy in patients with severe pulmonary artery stenosis often results in palliation of symptoms; however, surgery still is required often in these patients.
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We carried out flow cytometric analysis for multiparametric evaluation of cell surface markers related to cellular functions. Specifically, we studied the expression of CD4, CD8, CD3, CD16, CD19, HLA-DR, and CD14 macrophage receptors expression and cell cycle progression on cells exposed to ELF-EMF. In addition, we tested the effects of ELF-EMF on CD4 mRNA protein transcription and translation and the cell-cycle progression using an immunofluorescence method. Our data show that same CD surface marker expression are weakly influenced by electromagnetic fields, with no differences between cells exposed or not exposed to ELF-EMFs. However, when the CD4 protein generation was studied, an indication of protein production was found in lymphocytes exposed to ELF-EMF, as evidenced by immunofluorescence, Western blotting and RT-PCR analysis. CD16 and CD14 expression were affected by EMF exposure at all times studied (24, 48, 72 h). The results obtained with cell cycle analysis show that after 48 h of exposure to ELF-EMF, PHA-activated and not activated cells in S phase increase with respect to non-exposed cells. The findings from this study demonstrate that under our defined experimental conditions there is evidence that ELF-EMF has a slight effect on CD4, CD14 and CD16 receptor expression, while the other CD receptors are not affected.
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Antígenos CD/biossíntese , Antígenos CD4/genética , Campos Eletromagnéticos , Antígenos CD/genética , Biomarcadores , Western Blotting , Complexo CD3/biossíntese , Antígenos CD8/biossíntese , Ciclo Celular , Células Cultivadas , Técnica Indireta de Fluorescência para Anticorpo , Expressão Gênica , Humanos , Receptores de Lipopolissacarídeos/biossíntese , Monócitos/imunologia , RNA Mensageiro , Receptores de IgG/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição GênicaRESUMO
We present a SQUID susceptometer with a non-homogeneous magnetizing field which is null at the sensing coil and increases towards the patient position with a constant gradient plus a cubic term at large distances. Compared with the magnetizing fields of similar instruments described in the literature, our gradient field enhances the signal due to internal organs with respect to the signal due to superficial tissue. Preliminary measurements have been performed on phantoms of known magnetic susceptibility. The advantage of using a non-homogeneous field compared with a uniform field has been investigated in the case of a double-layer phantom.
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Espectroscopia de Ressonância de Spin Eletrônica , Magnetismo , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Humanos , Ferro/análise , Fígado/química , Imagens de FantasmasRESUMO
There is increasing evidence suggesting that extremely low frequency electromagnetic fields (ELF-EMF) may influence several cell functions. Here the effects of ELF-EMF were studied on the expression of CD4+ cell surface receptors of human peripheral blood mononuclear cells (PBMC) using fluorescence-activated cell sorter (FACScan). The expression of CD4+ in ELF-EMF exposed (24, 48 and 72 h) and not exposed PBMC were not statistically significant. In addition, a flow cytometric analysis was determined by using a fluorescent labeled antibody, at 24 and 72 h incubations. The amount of bound antibody was distributed with a slight difference in the ELF-EMF-exposed PBMC compared to the not exposed cells. Moreover, DNA CD4+ expression in PBMC strongly increased in exposed cells, resting and activated with Phytohaemaglutinin (PHA). When polymerase chain reaction was performed on CD4+ mRNA of PBMC an increase of CD4+ mRNA expression was found after the resting cells were exposed to ELF-EMF at 24 h compared to not exposed cells, while at 48 and 72 h no difference was found. In the cell cycle progression analysis, the PBMC exposed to ELF-EMF presented a significant increase of percentage expression of cell cycle progression in the S phase compared to not exposed cells; while in G1 and G2 phases, there were no differences. Our results provide new evidence that ELF-EMF can affect CD4+ expression in PBMC and describe an additional biological activity for ELF-EMF affecting CD4+ transcription and translation protein and the increase of the percentage expression of the cell cycle progression of the S phase.
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Antígenos CD4/metabolismo , Antígenos CD4/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/efeitos da radiação , Western Blotting , Antígenos CD4/genética , Ciclo Celular/efeitos da radiação , Citometria de Fluxo/métodos , Imunofluorescência , Humanos , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Transcrição GênicaRESUMO
The study of injury potentials associated with DC currents that generate the primary or secondary ST shifts during cardiac ischaemia is possible only through the invasive technique of the DC electrogram. Clinical surface ECG recordings are AC coupled and cannot be used. This paper reports the use of non-invasive and unshielded magnetocardiographic measurements to evaluate the DC injury currents associated with ST shifts during coronary artery occlusions in the isolated rabbit heart. The effect on the magnetic ST shift is studied under different ischaemic conditions including regional ischaemia, global ischaemia, global ischaemia following long periods of regional ischaemia, regional ischaemia after repeated episodes of reversible global ischaemia, and bilateral regional ischaemia. Recording of DC magnetic fields allows the characterization of primary and secondary ST displacement for each induced ischaemic condition. Our measurements show that the ST shift starts earlier when inducing ischaemia in hearts previously subjected to ischaemic episodes than in hearts where the ischaemia was produced for the first time.
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Eletrocardiografia , Isquemia Miocárdica/fisiopatologia , Animais , Campos Eletromagnéticos , CoelhosRESUMO
In the present study, we retrospectively examined our experience with the Palmaz-Schatz stent in patients with unstable angina to determine: a) different outcomes between patients with stable and unstable angina, b) correlation between the class of unstable angina and 1-month and 6-month results, c) correlation between lesion morphology and procedural complications. From January 1994 to January 1996, 160 patients with unstable angina (Group A) and 104 with stable angina (Group B) underwent coronary stenting. According to the modified Braunwald classification patients with unstable angina were divided into four classes. Lesion morphology was classified in simple and complex. Procedural success was 98% in Group A patients and 99% in Group B patients. We observed 9 (5.6%) major complications in Group A vs 2 (1.9%) in Group B. Subacute thrombosis occurred in 9 patients in Group A and in 2 patients in Group B and these different rates were responsible for the higher number of acute myocardial infarction and urgent revascularization procedures in Group A patients. At 6-month follow-up there were no differences between Group A and Group B patients. Patients in different classes of angina showed a similar cardiac event rate at 1-month and 6-month follow-up. We found 108 complex lesions in patients with unstable angina vs 20 in patients with stable angina (p = 0.0001). Among the 9 patients with unstable angina and subacute thrombosis, 6 had a complex lesion and 3 a simple lesion (NS). In conclusion, patients with unstable angina receiving intracoronary stent have similar clinical outcome at 1-month and 6-month follow-up as compared to patients with stable angina. The class of unstable angina and the complex morphology of the lesion are not related to procedural complications.