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1.
Rev Neurol (Paris) ; 178(5): 484-489, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35527085

RESUMO

Nuclear medicine with positron emission tomography (PET) and single photon emission computed tomography (SPECT) develops powerful tools in molecular imaging to help clinicians in the challenging diagnosis of parkinsonism. These techniques can provide biomarkers for neurodegenerative parkinsonism and to distinguish Parkinson disease (PD) from atypical parkinsonism. This review summarizes the main SPECT and PET contributions to the diagnosis of parkinsonism. We will also discuss new technologies in the field of nuclear imaging and their potential contribution to the diagnosis of parkinsonian syndromes.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Diagnóstico Diferencial , Humanos , Imagem Molecular/métodos , Doença de Parkinson/diagnóstico por imagem , Transtornos Parkinsonianos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
2.
Rev Neurol (Paris) ; 176(7-8): 608-613, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32164972

RESUMO

INTRODUCTION: Multiple system atrophy (MSA) is a neurodegenerative disorder in which vocal fold mobility can be affected, sometimes leading to life-threatening situations. Our aim was to know if laryngeal examination could help differentiate MSA from Parkinson's disease (PD). MATERIALS AND METHODS: Between 2004 to 2014, all consecutive patients diagnosed with probable MSA were included in this retrospective, monocentric study. Flexible laryngoscopy was obtained in 51 MSA patients and compared with 27 patients with Parkinson's disease (PD). Laryngeal muscles EMG was available in 6 MSA patients. RESULTS: Vocal fold motion impairments (VFMI) was found in 35 (68.6%) MSA patients: 15 (29.4%) had uni- or bilateral vocal fold abnormal movement (VFAM), 13 (25.5%) had uni- or bilateral vocal fold abductor paresis (VFABP), 4 (7.8%) had uni- or bilateral vocal fold adductor paresis (VFADP), 10 (19.6%) had bilateral vocal fold paralysis (BVFP). VFMI was found in 13 PD patients (48.1%) all of whom had VFADP. Presence of BVFP was found associated with stridor (P<0.001) and dysphagia (P=0.002). In all muscles examined in 6 MSA patients, the EMG showed neuropathic patterns. CONCLUSIONS: Our data support that VFMI may be encountered in two-thirds of MSA with a variable degree of gravity. Laryngological examination should be considered as a supplementary tool for the diagnosis and prognosis of MSA. VFMI in particular VFAM, VFABD and BVFP should be discussed as an additional possible red flag even at an early stage of MSA and could help discriminate MSA from PD.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Humanos , Prevalência , Estudos Retrospectivos , Prega Vocal
4.
Electromagn Biol Med ; 36(1): 55-62, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27368079

RESUMO

Heretofore only observed in living systems, we report that weak-field ion cyclotron resonance (ICR) also occurs in inanimate matter. Weak magnetic field (50 nT) hydronium ICR at the field combination (7.84 Hz, 7.5 µT) markedly changes water structure, as evidenced by finding an altered index of refraction exactly at this combined field. This observation utilizes a novel technique which measures the scattering of a He-Ne laser beam as the sample is exposed to a ramped magnetic field frequency. In addition to the hydronium resonance, we find evidence of ICR coupling to a more massive structure, possibly a tetrahedral combination of three waters and a single hydronium ion. To check our observations, we extended this technique to D2O, successfully predicting the specific ICR charge-to-mass ratio for D3O+ that alters the index of refraction.


Assuntos
Ciclotrons , Oniocompostos/química , Refratometria/instrumentação , Água/química , Óxido de Deutério/química , Campos Magnéticos , Vibração
5.
Environ Monit Assess ; 188(2): 118, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26812952

RESUMO

Monitoring surface water velocity during flood events is a challenging task. Techniques based on deploying instruments in the flow are often unfeasible due to high velocity and abundant sediment transport. A low-cost and versatile technology that provides continuous and automatic observations is still not available. Among remote methods, large-scale particle image velocimetry (LSPIV) is an optical method that computes surface water velocity maps from videos recorded with a camera. Here, we implement and critically analyze findings obtained from a recently introduced LSPIV experimental configuration during a flood event in the Tiber River at a cross section located in the center of Rome, Italy. We discuss the potential of LSPIV observations in challenging environmental conditions by presenting results from three tests performed during the hydrograph flood peak and recession limb of the event for different illumination and weather conditions. The obtained surface velocity maps are compared to the rating curve velocity and to benchmark velocity values. Experimental findings show that optical methods should be preferred in extreme conditions. However, their practical implementation may be associated with further hurdles and uncertainties.


Assuntos
Monitoramento Ambiental/instrumentação , Inundações/estatística & dados numéricos , Rios/química , Movimentos da Água , Monitoramento Ambiental/métodos , Cidade de Roma , Tempo (Meteorologia)
6.
Electromagn Biol Med ; 34(4): 370-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25020009

RESUMO

There is an ongoing question regarding the structure forming capabilities of water at ambient temperatures. To probe for different structures, we studied effects in pure water following magnetic field exposures corresponding to the ion cyclotron resonance of H3O(+). Included were measurements of conductivity and pH. We find that under ion cyclotron resonance (ICR) stimulation, water undergoes a transition to a form that is hydroxonium-like, with the subsequent emission of a transient 48.5 Hz magnetic signal, in the absence of any other measurable field. Our results indicate that hydronium resonance stimulation alters the structure of water, enhancing the concentration of EZ-water. These results are not only consistent with Del Giudice's model of electromagnetically coherent domains, but they can also be interpreted to show that these domains exist in quantized spin states.


Assuntos
Ciclotrons , Oniocompostos/química , Água/química , Campos Eletromagnéticos , Hidrogênio/química , Concentração de Íons de Hidrogênio , Íons , Temperatura , Fatores de Tempo , Vibração
7.
Hernia ; 28(3): 871-881, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38568350

RESUMO

BACKGROUND: Surgical management of large ventral hernias (VH) has remained a challenge. Various techniques like anterior component separation and posterior component separation (PCS) with transversus abdominis release (TAR) have been employed. Despite the initial success, the long-term efficacy of TAR is not yet comprehensively studied. Authors aimed to investigate the early-, medium-, and long-term outcomes and health-related quality of life (QoL) in patients treated with PCS and TAR. METHODS: This multicenter retrospective study analyzed data of 308 patients who underwent open PCS with TAR for primary or recurrent complex abdominal hernias between 2015 and 2020. The primary endpoint was the rate of hernia recurrence (HR) and mesh bulging (MB) at 3, 6, 12, 24, and 36 months. Secondary outcomes included surgical site events and QoL, assessed using EuraHS-QoL score. RESULTS: The average follow-up was 38.3 ± 12.7 months. The overall HR rate was 3.5% and the MB rate was 4.7%. Most of the recurrences were detected by clinical and ultrasound examination. QoL metrics showed improvement post-surgery. CONCLUSIONS: This study supports the long-term efficacy of PCS with TAR in the treatment of large and complex VH, with a low recurrence rate and an improvement in QoL. Further research is needed for a more in-depth understanding of these outcomes and the factors affecting them.


Assuntos
Músculos Abdominais , Hérnia Ventral , Herniorrafia , Qualidade de Vida , Telas Cirúrgicas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Herniorrafia/métodos , Pessoa de Meia-Idade , Hérnia Ventral/cirurgia , Músculos Abdominais/cirurgia , Idoso , Recidiva , Itália
9.
J Neurol ; 270(10): 4841-4850, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37330976

RESUMO

BACKGROUND: New diagnostic criteria of Progressive Supranuclear Palsy (PSP) have highlighted the interest of Eye Movement Records (EMR) at the early stage of the disease. OBJECTIVES: To investigate the metabolic brain correlates of ocular motor dysfunction using [18F] Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) in early PSP. METHODS: Retrospective observational descriptive study on longitudinal data with patients who underwent EMR and FDG-PET at the stage of suggestive and possible PSP according to Movement Disorders Society criteria. Longitudinal follow-up enables to confirm diagnosis of probable PSP. Using the Statistical Parametric Mapping software, we performed whole-brain voxel-based correlations between oculomotor variables and FDG-PET metabolism. RESULTS: Thirty-seven patients with early PSP who fulfilled criteria of probable PSP during the follow-up were included. Decrease in the gain of vertical saccades correlated with reduced metabolism in Superior Colliculi (SC). We also found a positive correlation between mean velocity of horizontal saccades and SC metabolism as well as dorsal nuclei in the pons. Finally, increase in horizontal saccades latencies correlated with decrease of posterior parietal metabolism. CONCLUSIONS: These findings suggest the early involvement of SC in saccadic dysfunction in the course of PSP.


Assuntos
Fluordesoxiglucose F18 , Paralisia Supranuclear Progressiva , Humanos , Fluordesoxiglucose F18/metabolismo , Estudos Retrospectivos , Movimentos Sacádicos , Encéfalo , Paralisia Supranuclear Progressiva/diagnóstico , Tomografia por Emissão de Pósitrons/métodos
10.
Eur J Neurol ; 18(12): 1417-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21819489

RESUMO

BACKGROUND AND PURPOSE: There are other options open to patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who are non-responders to conventional treatment, including immunosuppressive and immunomodulatory agents (IA). The aim of this study was to assess whether the use of IA is able to increase the number of responders. METHODS: Clinical and electrophysiological data of patients with refractory CIDP, followed at 10 Italian centres, were collected, and the clinical outcome (Rankin Scale) and drug side effects (SE) for the different therapies were analysed. RESULTS: A total of 110 patients were included. These patients underwent 158 different therapeutic procedures with IA. Seventy-seven patients were treated with azathioprine, 18 rituximab, 13 cyclophosphamide, 12 mycophenolate mofetil, 12 cyclosporine, 12 methotrexate, 11 interferon-alpha and three interferon beta-1a. The percentage of patients who responded to azathioprine (27%) was comparable to the percentage of responders to other therapies, after the exclusion of interferon beta-1a that was not effective in any of the three patients treated. The percentage of SE ranges from 8% (methotrexate) to 50% (cyclosporine). CONCLUSIONS: One-fourth of patients, refractory to conventional treatment, showed an improvement in their disability with IA. Methotrexate had the lowest SE; cyclosporine was associated with severe SE and often led to drug discontinuation.


Assuntos
Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais Murinos/uso terapêutico , Axônios/patologia , Azatioprina/uso terapêutico , Criança , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Resistência a Medicamentos , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Interferon beta-1a , Interferon-alfa/uso terapêutico , Interferon beta/uso terapêutico , Itália , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Plasmaferese , Indução de Remissão , Estudos Retrospectivos , Rituximab , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
11.
Eur Rev Med Pharmacol Sci ; 15(1): 61-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21381500

RESUMO

OBJECTIVES: One important limitation in cell therapy protocols, and regenerative medicine (an innovative and promising strategy for different pathologies treatment), is the lack of knowledge about cells engraftment, proliferation and differentiation. In order to allow an efficient and successful cell transplant, it is necessary to predict the logistics, economic and timing issues during cellular injection. It has been reported that several parameters, such as cells number, temperature and extracellular pH (pH0) value can influence metabolic pathways and cellular growth. Numerical analysis and model can help to reduce and understand the effects of the above environmental conditions on cell survival. The aim of this paper is to develop the first step of cells transplantation in order to identify "in vitro", which parameters can be useful to develop and validate a numerical model, able to evaluate "in vivo" cells engraftment and proliferation. MATERIAL AND METHODS: We studied the variation of extracellular parameters--such as medium volume, buffer system, nutrient concentrations and temperature on human colon carcinoma cells (CaCo-2) "in vitro culture"--pursuing the goal of understanding in deeper details cellular processes such as growth, metabolic activity, survival and pH0. RESULTS: Results showed that CaCo-2 cells growth and mortality increase after two days in culture when cells were suspended in 3.5 ml volume to respect of 10 ml volume. Different temperature values influenced CaCo-2 cells growth and metabolic activity showing a direct relationship with the volume of the medium. CONCLUSIONS: Our results describe as CaCo-2 cell growth, metabolic activity, mortality and extracellular pH were influenced by extracellular parameters, enabling us to develop and validate a numerical model to be use to predict cells engraftment and proliferation.


Assuntos
Proliferação de Células , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos , Temperatura
12.
G Chir ; 32(8-9): 357-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22018255

RESUMO

Researchers believe that human muscle-derived cells are able to restore leak-point pressure to normal levels by differentiating into new muscle fibres that prevent anal sphincter muscle atrophy. Laboratory data are needed to identify exactly how these cells work to regenerate muscle. The objective of this study is to test whether stem cells can be employed to treat internal anal sphincter (IAS) injuries in humans; to this end, this work will use a two-step process to study: first, the effectiveness of the treatment in a sample of animals with artificial injuries to the IAS and then to verify the results in a population of selected humans affected by pathology.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Incontinência Fecal/cirurgia , Transplante de Células-Tronco Mesenquimais , Canal Anal/fisiopatologia , Canal Anal/cirurgia , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Dexametasona/farmacologia , Humanos , Hidrocortisona/farmacologia , Modelos Animais , Desenvolvimento Muscular/efeitos dos fármacos , Músculo Esquelético/citologia , Ratos , Ratos Mutantes , Ratos Wistar , Regeneração , Células Satélites de Músculo Esquelético/fisiologia , Imunodeficiência Combinada Severa , Transplante Heterólogo
13.
Acta Neurol Scand ; 122(1): 36-40, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20002006

RESUMO

OBJECTIVES: Peripheral neuropathy has been reported in association with end-stage liver disease, but there is only a limited number of reports on the incidence and features of these neuropathies. MATERIALS AND METHODS: In this study, 83 patients awaiting liver transplantation were evaluated for the presence of peripheral and autonomic neuropathy. RESULTS: Sixty-five percent of the patients had evidence of neuropathy, in agreement with peripheral NCS or cardiovascular autonomic function test. The neuropathy was more frequent in patients with advanced hepatic failure, evaluated with the MELD score. The most frequent abnormalities in nerve conduction studies were sensory-motor neuropathies and sensory neuropathies, with a length-dependent pattern. CONCLUSION: Peripheral neuropathy and autonomic neuropathy are common in patients with end-stage liver disease with different etiology and correlate with the severity of the liver disease.


Assuntos
Falência Renal Crônica/complicações , Polineuropatias/etiologia , Adulto , Idoso , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Falência Renal Crônica/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Polineuropatias/diagnóstico , Polineuropatias/epidemiologia , Prevalência , Estudos Retrospectivos , Índice de Gravidade de Doença
14.
Science ; 232(4757): 1554-6, 1986 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-3012779

RESUMO

In many viral infections the host cell carries the viral genome without producing viral particles, a phenomenon known as viral latency. The cellular mechanisms by which viral latency is maintained or viral replication is induced are not known. The modulation of intracellular calcium concentrations by calcium ionophores induced Epstein-Barr viral antigens in lymphoblastoid cell lines that carry the virus. When calcium ionophores were used in conjunction with direct activators of protein kinase C (12-O-tetradecanoyl phorbol-13-acetate and a synthetic diacylglycerol), a greater induction of viral antigens was observed than with either agent alone. Activation of protein kinase C may be required for the expression of the viral genome.


Assuntos
Cálcio/farmacologia , Transformação Celular Viral/efeitos dos fármacos , Genes Virais/efeitos dos fármacos , Herpesvirus Humano 4/genética , Aminoquinolinas , Linfoma de Burkitt , Calcimicina/farmacologia , Linhagem Celular , Meios de Cultura , Éteres/farmacologia , Corantes Fluorescentes , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Ionomicina , Cinética , Acetato de Tetradecanoilforbol/farmacologia
15.
J Biomed Biotechnol ; 2009: 834239, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19672456

RESUMO

Electromagnetic fields are an assessed cause of prolonging free radicals lifespan. This study was carried out to investigate the influence of extremely low frequency electromagnetic fields on protein oxidation and on the 20S proteasome functionality, the complex responsible for the degradation of oxidized proteins. Caco 2 cells were exposed, for 24-72 hours, to 1 mT, 50 Hz electromagnetic fields. The treatment induced a time-dependent increase both in cell growth and in protein oxidation, more evident in the presence of TPA, while no changes in cell viability were detected. Exposing the cells to 50 Hz electromagnetic fields caused a global activation of the 20S proteasome catalytic components, particularly evident at 72 hours exposure and in the presence of TPA. The finding that EGCG, a natural antioxidant compound, counteracted the field-related pro-oxidant effects demonstrates that the increased proteasome activity was due to an enhancement in intracellular free radicals.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/efeitos da radiação , Carbonilação Proteica/efeitos da radiação , Análise de Variância , Células CACO-2 , Carcinógenos/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta à Radiação , Humanos , Protetores contra Radiação/farmacologia , Temperatura , Acetato de Tetradecanoilforbol/farmacologia
16.
Sci Data ; 6: 180309, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644852

RESUMO

Identifying floodplain boundaries is of paramount importance for earth, environmental and socioeconomic studies addressing riverine risk and resource management. However, to date, a global floodplain delineation using a homogeneous procedure has not been constructed. In this paper, we present the first, comprehensive, high-resolution, gridded dataset of Earth's floodplains at 250-m resolution (GFPLAIN250m). We use the Shuttle Radar Topography Mission (SRTM) digital terrain model and set of terrain analysis procedures for geomorphic floodplain delineations. The elevation data are processed by a fast geospatial tool for floodplain mapping available for download at https://github.com/fnardi/GFPLAIN. The GFPLAIN250m dataset can support many applications, including flood hazard mapping, habitat restoration, development studies, and the analysis of human-flood interactions. To test the GFPLAIN250m dataset, we perform a consistency analysis with floodplain delineations derived by flood hazard modelling studies in Europe.

17.
Gene Ther ; 15(3): 161-70, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18033312

RESUMO

Human embryonic stem cells (hESCs) may become important for cardiac repair due to their potentially unlimited ability to generate cardiomyocytes (CMCs). Moreover, genetic manipulation of hESC-derived CMCs would be a very promising technique for curing myocardial disorders. At the present time, however, inducing the differentiation of hESCs into CMCs is extremely difficult and, therefore, an easy and standardizable technique is needed to evaluate differentiation strategies. Vectors driving cardiac-specific expression may represent an important tool not only for monitoring new cardiac-differentiation strategies, but also for the manipulation of cardiac differentiation of ESCs. To this aim, we generated cardiac-specific lentiviral vectors (LVVs) in which expression is driven by a short fragment of the cardiac troponin-I proximal promoter (TNNI3) with a human cardiac alpha-actin enhancer, and tested its suitability in inducing tissue-specific gene expression and ability to track the CMC lineage during differentiation of ESCs. We determined that (1) TNNI3-LVVs efficiently drive cardiac-specific gene expression and mark the cardiomyogenic lineage in human and mouse ESC differentiation systems (2) the cardiac alpha-actin enhancer confers a further increase in gene-expression specificity of TNNI3-LVVs in hESCs. Although this technique may not be useful in tracking small numbers of cells, data suggested that TNNI3-based LVVs are a powerful tool for manipulating human ESCs and modifying hESC-derived CMCs.


Assuntos
Células-Tronco Embrionárias/citologia , Terapia Genética/métodos , Insuficiência Cardíaca/terapia , Miócitos Cardíacos/citologia , Actinas/genética , Animais , Diferenciação Celular , Linhagem Celular , Elementos Facilitadores Genéticos , Citometria de Fluxo , Engenharia Genética , Vetores Genéticos/farmacologia , Humanos , Lentivirus/genética , Camundongos , Regiões Promotoras Genéticas , Transdução Genética/métodos , Troponina I/genética
18.
J Microsc ; 229(Pt 3): 551-4, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18331509

RESUMO

Human HaCaT cells, exposed for 24 h to a 1 mT (rms) 50 Hz sinusoidal magnetic field in a temperature-regulated solenoid, suffer detectable changes in their biochemical properties and shapes. By using infrared wavelength-selective scanning near-field optical microscopy, we observed changes in the distribution of the inner chemical functional groups and in the cell morphology with a resolution of 80-100 nm.


Assuntos
Campos Eletromagnéticos , Queratinócitos , Pele/citologia , Linhagem Celular , Humanos , Raios Infravermelhos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Queratinócitos/ultraestrutura , Microscopia de Varredura por Sonda
19.
Biochim Biophys Acta ; 1280(1): 161-8, 1996 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-8634311

RESUMO

Infection of Epstein Barr virus (EBV) to its host cells is initiated by the attachment of the glycoprotein gp 350/220 to the CR2 molecule. We used the sensitivity at the polar environment of the fluorescent probe Laurdan to study the membrane viscosity distribution from single leaving cells on two lymphoid cell lines Raji and Akata. Lipid analysis on both cells line demonstrated a lower cholesterol to phospholipid molar ratio on Akata than Raji cells. Cell fluidity analysis by Laurdan generalized emission polarization (GP) or by DPH polarization, indicated that membrane viscosity of Akata was lower than Raji cells. This difference was correlated to the increased susceptibility of Akata cells in expressing EBV early antigens (EA) after EBV superinfection.


Assuntos
Membrana Celular/fisiologia , Herpesvirus Humano 4/fisiologia , Fluidez de Membrana , 2-Naftilamina/análogos & derivados , Linhagem Celular , Colesterol/metabolismo , Corantes Fluorescentes , Herpesvirus Humano 4/patogenicidade , Humanos , Lauratos , Fusão de Membrana , Lipídeos de Membrana/metabolismo , Microscopia de Fluorescência , Fosfolipídeos/metabolismo , Proteína Quinase C/metabolismo , Sensibilidade e Especificidade , Temperatura , Termodinâmica , Viscosidade
20.
Biochim Biophys Acta ; 1357(3): 281-90, 1997 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-9268052

RESUMO

Human B lymphoid cells (Raji) were exposed for 72 h to a 50 Hz sinusoidal magnetic field at a density of 2 milliTesla (rms). The results of exposure showed a decrease in membrane fluidity as detected by Laurdan emission spectroscopy and DPH fluorescence polarization. Field exposure also resulted in a reorganization of cytoskeletal components. Scanning electron microscopy (SEM) revealed a loss of microvilli in the exposed cells. This change in plasma membrane morphology was accompanied by a different actin distribution, as detected by phalloidin fluorescence. We also present evidence that EMF exposure of Raji cells can interfere with protein phosphorylation. Our observations confirm the hypothesis that electric and magnetic fields may modify the plasma membrane structure and interfere with the initiation of the signal cascade pathways.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Actinas/ultraestrutura , Divisão Celular , Linhagem Celular/efeitos da radiação , Linhagem Celular/ultraestrutura , Membrana Celular/efeitos da radiação , Citoesqueleto/efeitos da radiação , Citoesqueleto/ultraestrutura , Humanos , Fluidez de Membrana/efeitos da radiação , Microscopia Confocal , Microscopia Eletrônica de Varredura , Faloidina/análogos & derivados , Proteínas Quinases/metabolismo
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