RESUMEN
BACKGROUND: High level of attendance by population is considered a proof of the efficacy in the screening programmes. Public health aims to increase people's attendance to cancer screening. The study aimed at assessing the level of knowledge and awareness about screening of citizens in Cagliari, from June to July 2016. METHODS: Recruitment took place near the atrium of the two main shopping centres of the city. The sample included 270 adults (138 men), 18-75 years old (mean age 46 years old). The information gathered from interviews were categorized by dichotomizing answers according to the knowledge and understanding of the discussed topics. Descriptive analysis was performed. The Chi-square test was used to assess gender and educational differences. RESULTS: Results show that population's knowledge of screening is limited. Although the word "screening" is known, only half of the people who declared to have heard of this word know about the aim of screening. Colorectal cancer screening is the least known. Men and people with lower education are less informed than women and those with high education level. CONCLUSION: In order to raise knowledge and awareness about cancer screening, special attention should be paid to communication and to the use of plain language. Future action should highlight the benefit of the screening procedure and thus contributing to spread the cancer prevention culture. Gender and socioeconomic inequalities must be taken into account when planning screening communication campaigns. General practitioner are highly trusted by people. They could play a decisive role to promote screening attendance.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Conocimientos, Actitudes y Práctica en Salud , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Adulto , Anciano , Escolaridad , Femenino , Educación en Salud , Promoción de la Salud , Humanos , Italia , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto JovenRESUMEN
BACKGROUND: The Curitiba Statement of health promotion and equity is the main result of the World Conference on International Union for Health Promotion and Education (IUHPE - UIPES), held in May 2016 in Curitiba. The Curitiba Statement is the outcome of a participatory process, result of collaboration of all conference participants. The Curitiba Statement represents the continuity from Ottawa Charter for Health Promotion. This document remembers and asks to International Organizations, Governments, at all levels of the Institutions, the Health Sector, Citizens and Health Professionals and Researchers to change and eliminate all forms of discrimination and exclusion. STUDY DESIGN: Description of the translation and validation process. METHODS: The translation process from Spanish and English is based on the translation techniques enumerated by Fawcett in 1997: borrowing, calque, literal translation, transposition, modulation, reformulation, adaptation. RESULTS: The translation process produced some critical issues shifting from English to Italian: the most critical words and expressions correspond to the more significant ones of the Curitiba Statement, and these issues are reflected in research, politics and practice. In particular, we analyzed the translation of Inequity, Advocate, and Players, and then discussed their use in different expressions in the original text. CONCLUSION: Considering the Curitiba Statement's message has to be transversal, and it is addressed not only to Professionals but to all Citizens, researchers have made the choice of a clear translation for the Italian readers, not always similar to English form, but consistent and faithful in its content. To spread the culture and practice of Health Promotion, a deep attention in the translation of international documents could allow the propagation of ideas and strategies, from global to local.
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Política de Salud , Promoción de la Salud/normas , Prejuicio/prevención & control , Justicia Social/normas , Salud Global , Disparidades en Atención de Salud , Humanos , Italia , TraduccionesRESUMEN
Gliomas are histologically graded by cellularity, cytological atypia, necrosis, mitotic figures, and vascular proliferation, features associated with biologically aggressive behaviour. However, abundant evidence suggests the presence of unrecognized, clinically relevant subclasses of the diffuse gliomas, both in respect to their underlying molecular phenotype and their clinical response to therapy. It is well-known that patient prognosis and therapeutic decisions rely on accurate pathological grading. Recently, it was reported that human gliomas accumulate lipid droplets during progression, suggesting a lipid metabolism impairment. Considering the crucial role of peroxisomes in lipid metabolism, in the present work we studied the expression profiles of proteins either exclusively localized to peroxisomes, such as peroxin14 (PEX14), peroxisomal membrane protein 70Kda (PMP70), acyl-CoA oxidase, thiolase, or partially associated to peroxisomes such as Hydroxymethylglutaryl-CoA reductase (HMGCoA-red) and peroxisomal-related proteins, namely PPARalpha, in human glioma specimens at different grades of malignancy. Moreover, Nile red staining of lipid droplets, thin layer chromatography (TLC) and proton nuclear magnetic resonance spectroscopy (NMR) were carried out in order to correlate the biochemical results with the lipid content of tumor tissues. The results obtained indicate that correlating the malignancy grade with the expression of peroxisomal genes and proteins, may constitute a sensitive tool to highlight possible subtypes not recognized by the classical histological techniques.
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Glioma/metabolismo , Metabolismo de los Lípidos , Peroxisomas/química , Transportadoras de Casetes de Unión a ATP/análisis , Acil-CoA Oxidasa/análisis , Western Blotting , Glioma/química , Humanos , Inmunohistoquímica , Espectroscopía de Resonancia Magnética , Proteínas de la Membrana/análisis , Reacción en Cadena de la Polimerasa , Proteínas Represoras/análisisRESUMEN
Endovascular catheterisation is performed by an interventional radiologist using fluoroscopic guide and contrast-media. The X-Ray exposure both of the patient and of the operators can induce heavy collateral effects. The present paper describes an innovative magnetic position/orientation indicator capable to drive the endovascular probe during in-vivo medical diagnostic or interventional procedures. It uses the magnetic field produced by a thin permanent magnet installed on the endovascular probe and magnetic field sensors positioned outside the patient body: this allow the elimination of repetitive X-Ray scans used to monitor the probe position. The aims of the proposed system are: to drive the catheter inside the patient vascular tree with a reduction of the X-Ray exposure both of the patient and of the personnel involved in the intervention; to allow a more comfortable operative condition for the personnel due to the reduction of the time they wear X-Ray protective systems. The paper reports the mathematical problem formulation, the numerical simulations for the magnetic field calculation produced by the thin endovascular permanent magnet and the system design of the usable hardware.
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Modelos Teóricos , Monitoreo Intraoperatorio/efectos adversos , Exposición Profesional/prevención & control , Tomografía Computarizada por Rayos X/efectos adversos , Procedimientos Quirúrgicos Vasculares , Humanos , Magnetismo , Exposición Profesional/efectos adversos , Factores de TiempoRESUMEN
OBJECTIVE: In Italy the law on industrial risk has emphasised the necessity of building a local information process to answer people's questions on safety and provide greater community participation in risk management. The aim of this research is to analyse the local population's ideas and expectations of a participatory approach in risk management in order to design a risk communication programme based on health promotion principles. DESIGN, SETTING AND PARTICIPANTS: The study was carry out in Portoscuso (Italy), an industrial district. A questionnaire was administrated through home interviews to 147 citizens. MAIN RESULTS: Six risk management styles were identified on the basis of citizens' trust in the different stakeholders. Additional parameters (importance of information, organisations they would trust to get information on industrial risks, preferred risk communication methodologies) were analysed according to the management styles. CONCLUSIONS: On the basis of these elements, a multi-approach strategy could be proposed. Each management style can have different roles. A programme of public forums could involve citizens with an interactive approach, interactive courses could involve citizens with a semi-participative approach, and leaflets and booklets could inform citizens oriented towards unidirectional communication. The participative process should always be open to new contributions from citizens who are not directly involved, and should allow for flexibility in the form and nature of partnership, as well as the details of implementation.
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Actitud , Comunicación , Industrias , Salud Laboral , Accidentes de Trabajo/prevención & control , Adolescente , Adulto , Participación de la Comunidad , Femenino , Promoción de la Salud , Humanos , Italia , Masculino , Persona de Mediana Edad , Riesgo , Población RuralRESUMEN
The authors examined the influence of APOE and human leukocyte antigen-DRB1-DQB1 polymorphisms on the course of multiple sclerosis in 871 patients, 773 with relapsing and 98 with primary progressive disease, and 348 control subjects. The risk of the primary progressive course was increased (odds ratio = 6.81, p = 0.002) in women carrying the APOE4 but not the DRB1-DQB1 predisposing genotype, suggesting in this subgroup of patients a reciprocal influence between these genes and gender in modulating clinical variability of the disease.
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Apolipoproteínas E/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Apolipoproteína E4 , Progresión de la Enfermedad , Femenino , Genes MHC Clase II , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos/genética , Humanos , Italia/epidemiología , Masculino , Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente/epidemiología , Esclerosis Múltiple Recurrente-Remitente/genética , Esclerosis Múltiple Recurrente-Remitente/inmunología , Polimorfismo Genético , Riesgo , Factores SexualesRESUMEN
Clinical MRI/MRS applications require radio frequency (RF) surface coils positioned at an arbitrary angle alpha with respect to B(0). In these experimental conditions the standard circular loop (CL) coil, producing an axial RF field, shows a large signal loss in the central region of interest (ROI). We demonstrate that transverse-field figure-of-eight (FO8) RF surface coils design are not subject to the same amount of signal loss in the central ROI as loop coils when their orientations are changed. The 1.5-T CL and FO8 prototypes (diameter = 10 cm) were built on Plexiglas using copper strips (width = 4 mm, thickness = 100 mum). The two linear elements of the FO8 coil were 1 cm apart. Axial spoiled gradient echo (SPGR) images of a phantom containing doped water were acquired with the coil plane at alpha=0 degrees , 45 degrees , and 90 degrees . As alpha increases, the CL images show, in the central ROI, a signal that decreases from a maximum value to zero. Whereas the FO8 images show, in the same ROI, a signal that varies little from the maximum value (20%). Optimized FO8 coils can be oriented with the coil plane positioned along any direction with respect to B(0) without significant signal loss. Transverse RF coil design should be useful for clinical MRS studies and also for parallel imaging techniques where versatile RF coils disposed along arbitrary directions are required.
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Aumento de la Imagen/instrumentación , Imagen por Resonancia Magnética/instrumentación , Magnetismo/instrumentación , Modelos Biológicos , Transductores , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Muslo/anatomía & histologíaRESUMEN
Several lines of evidence indicate a genetic contribution to multiple sclerosis (MS) both in terms of predisposition to the disease and of immunological mechanisms which are known to play crucial roles in MS pathogenesis. The presence of high- and low-risk areas for MS in neighbouring regions supports the theory that MS predisposition is influenced by a complex interaction of genetic and environmental factors. Therefore, the use of genetically homogeneous and geographically isolated populations becomes an increasing requirement to reduce biasing biological variables. Sardinians fulfil these conditions well because of their different phylogeny from Europeans and the unique selective pressures which shaped their genome. Sardinians display amongst the highest MS prevalence rates world-wide and increasing MS incidence rates over time. Also, MS in Sardinia is linked to distinct human leucocyte antigen (HLA) alleles and associated to different patterns of cytokine production from lymphoid cells of different HLA subtypes. In this context, recent findings and future perspectives on the peculiarities of Sardinian MS concerning genetic, immunological and epidemiological aspects are presented. So far, our results indicate that variations at the level of territorial distribution and HLA-association are present which render MS heterogeneous even in this ethnically homogeneous population.
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Esclerosis Múltiple/epidemiología , Humanos , Italia/epidemiología , Esclerosis Múltiple/genética , Esclerosis Múltiple/inmunología , PrevalenciaRESUMEN
Several studies indicate that patients with multiple sclerosis (MS) have low serum levels of the endogenous antioxidant uric acid (UA), although it has not been established whether UA is primarily deficient or secondarily reduced due to its peroxynitrite scavenging activity. We measured serum urate levels in 124 MS patients and 124 age- and sex-matched controls with other neurological diseases. In addition, we compared UA levels when MS patients were stratified according to disease activity (by means of clinical examination and MRI), duration, disability and course. MS patients had significantly lower serum urate levels than controls (p= 0.001). However, UA levels did not significantly correlate with disease activity, duration, disability or course. Our study favors the view that reduced UA in MS is a primary, constitutive loss of protection against oxidative agents, which deserves further pathogenetic elucidation aimed at future therapeutic strategies.
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Esclerosis Múltiple/sangre , Ácido Úrico/sangre , Adolescente , Adulto , Enfermedad Crónica , Femenino , Gadolinio DTPA , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Valor Predictivo de las Pruebas , Valores de Referencia , Índice de Severidad de la Enfermedad , Factores SexualesRESUMEN
Electron paramagnetic resonance imaging (EPRI) is a recently developed imaging technique employed in the study of free radicals in living systems. A full understanding of many physiological and pathological processes involving free radicals has not yet been attempted. The reason for this is that whilst nuclear magnetic resonance imaging (NMRI) is able to generate very accurate images of soft tissues and organs, EPRI does not have this capability because of its sensitivity limitations and the large linewidths of paramagnetic probes. This work describes the development and optimization of a multimodal apparatus capable of performing both pulsed EPRI and NMRI experiments on the same sample. The instrument combines the possibilities offered by both techniques: the functional and biochemical information achieved with EPRI, and the high-resolution anatomical images generated by NMRI. At present, these experiments are performed by moving the sample from an EPRI spectrometer to an NMRI apparatus. Consequently, the acquisition times are very long and several problems arise in image reconstruction. On the other hand, a unique apparatus operating in the two modalities greatly reduces the acquisition times and makes it possible to relate accurately the observed distribution of electron spin density with the anatomical description of individual organs. The experiments are performed at 357 Gauss, corresponding to a resonance frequency of 1.52 MHz for NMR and 1 GHz for EPR. In the present work, a detailed description of the apparatus is reported, including the main magnet, the gradient assembly, the multimodal cavity and the transmitter and receiver systems. The preliminary experimental results obtained by this apparatus are presented.
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Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Espectroscopía de Resonancia por Spin del Electrón/métodos , Espectroscopía de Resonancia Magnética/instrumentación , Espectroscopía de Resonancia Magnética/métodos , Electrones , Magnetismo , Fantasmas de Imagen , Factores de TiempoRESUMEN
Chlamydia pneumoniae infection is a common event in neurological patients and recovery of C. pneumoniae DNA in the cerebrospinal fluids (CSF) of multiple sclerosis (MS) patients could represent an epiphenomenon. We assessed the relevance of C. pneumoniae infection in 62 CSF samples from 32 MS patients and 30 neurological controls by means of PCR, immunofluorescence microscopy, enzyme-linked fluorescence and antibody detection. Multiple sclerosis (9.3%) and neurological controls (13.3) had similar percentage of anti-C. pneumoniae antibodies. However, C. pneumoniae DNA was only detectable in MS patients' CSF (9.3%). Our data support the hypothesis that C. pneumoniae persistence in some MS patients may be the result of an impaired clearance within the central nervous system.
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Líquido Cefalorraquídeo/microbiología , Chlamydophila pneumoniae/aislamiento & purificación , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/microbiología , Enfermedades del Sistema Nervioso/líquido cefalorraquídeo , Enfermedades del Sistema Nervioso/microbiología , Adulto , Anticuerpos Antibacterianos/análisis , Chlamydophila pneumoniae/genética , Chlamydophila pneumoniae/inmunología , ADN Bacteriano/análisis , Femenino , Humanos , MasculinoRESUMEN
Continuous wave and pulsed wave electron paramagnetic resonance imaging (EPRI) makes use of classical methods of acquisition of projections. Acquisition/reconstruction techniques, such as spin-echo, gradient-echo, etc, cannot be applied to EPRI because they would require very short switching times for the gradient coils. Due to the use of the polar acquisition technique, it is necessary to define a centre of rotation about which the measured projections are rotated during the reconstruction process. This centre represents the point at which the field gradient coils must produce zero magnetic field. Due to the presence of a magnetic field control system that serves to compensate for field variations, principally due to heating, some interference can occur in the control system between the main magnetic field and the magnetic field produced by the gradient coils. The effect changes as the orientation changes. This results in a shift of the centres of the projections as a function of the variation of magnetic field produced by the gradient coils on the control Hall probe. If this condition is present, some artefacts can appear on the reconstructed image. This effect is irrelevant when EPR is used for imaging of paramagnetic probes whose linewidths are of the order of 10(-4) T, while it can be significant in the case of linewidths of the order of 10(-5) T or lower or when EPR is used in microimaging applications (i.e. for high values of magnetic field gradient). We describe the effects that misalignments of the projections have on the reconstructed images. We present a useful method for estimating the real position of the centre and correcting the measured projections before the application of the reconstruction algorithm. Moreover, we demonstrate the functioning of our technique by presenting some examples of EPR reconstruction collected by an X-band EPR imaging apparatus.
Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Espectroscopía de Resonancia por Spin del Electrón/métodos , Procesamiento de Imagen Asistido por Computador , Algoritmos , Magnetismo , Modelos EstadísticosRESUMEN
An omega-space adaptive acquisition technique for MRI from projections is presented. It is based on the evaluation of the information content of a set composed of four initial projections, measured at angles 0 degrees, 45 degrees, 90 degrees, and 135 degrees, followed by the selection of new angles where the information content is maximum. An entropy function is defined on the power spectrum of the projections that is useful for evaluating the information content of each projection. The method makes it possible to reduce the total acquisition time with little degradation of the reconstructed image and it adapts to the arbitrary shape of the sample. For this reason, it can be particularly useful in those applications where acquisition from projections is strongly recommended to save acquisition time, such as functional MRI, imaging of species having very short T(2), or angiography. The method has been tested both on simulated data and on experimental data collected by a commercial MRI apparatus. The method has also been compared to the regular acquisition method, that is, the standard acquisition method in MRI from projections.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador , Fantasmas de ImagenRESUMEN
Pulsed nuclear magnetic resonance imaging (NMRI) apparatus has developed very quickly. On the other hand, the development of apparatus for pulsed electron paramagnetic resonance imaging (EPRI) has been very slow. This fact is due to the extremely reduced relaxation times of the paramagnetic probes. EPR linewidths are larger than typical NMR linewidths. These large linewidths are also responsible for a substantial worsening of spatial resolution. Due to the brevity of the electronic relaxation times, not all the acquisition/reconstruction techniques currently used in NMRI (such as spin-echo, gradient-echo, etc) can be applied in pulsed EPRI. In fact, the usable sequences in pulsed EPRI are only acquisitions from projections, where it is possible to use stationary magnetic field gradients. Moreover, the use of high fixed magnetic field gradients induces a short decay time constant T2*. The low T2* value can make it impossible for the analogue to digital conversion system (ADC) to reproduce signal variations during the whole acquisition interval and the resolution can worsen. A new pulsed EPRI acquisition sequence from projections, based on selective reception, is presented that is particularly useful in solving the problems of worsening of spatial resolution associated with the use of an ADC. In order to demonstrate the capabilities of our acquisition method, simulated numerical tests will also be reported.
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Espectroscopía de Resonancia por Spin del Electrón/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Modelos Teóricos , Fantasmas de Imagen , Factores de TiempoRESUMEN
A novel coupling method that optimizes the axial RF distribution of low-frequency EPR loop-gap resonators is presented. It consists of a resonant coupling loop positioned at the centre of a two-section loop-gap resonator. This arrangement ensures a symmetrical distribution of the radio frequency field along the axis of the resonator. The design of a central coupling system suitable for EPR resonators operating at about 220 MHz is described. Experimental results show that with the central coupling system the RF field is symmetrical and has a very good axial homogeneity (100% of the resonator length).
Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Ondas de Radio , Fenómenos Biofísicos , Biofisica , Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Espectroscopía de Resonancia por Spin del Electrón/estadística & datos numéricos , Electrónica Médica/instrumentación , Diseño de Equipo , Estudios de Evaluación como AsuntoRESUMEN
The qualitative equivalence between the Fourier reconstruction (FR) algorithm and the filtered back projection (FBP) algorithm is demonstrated when all the different phase errors that can occur in FR are eliminated. The causes of phase errors are underlined and methods to eliminate them are presented. The practical comparison between FR and FBP has been evaluated on a numerical test image and the results are reported, demonstrating the qualitative equivalence. FR has the advantage of being very computationally efficient. In fact, the time spent to obtain the FR image was 1/20 of that used to obtain the FBP image. Because of the computational efficiency of FR and the good quality of the results obtained, an iterative version of FR has been used to implement the spectral-spatial imaging (SSI) algorithm in the field of electron paramagnetic resonance imaging (EPRI). An experimental example, demonstrating its good performance, is reported.
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Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Análisis de Fourier , Humanos , Fantasmas de ImagenRESUMEN
In the last decade radiofrequency continuous-wave EPR spectrometers have been developed to detect and localize free radicals in vivo. Only recently, pulsed radiofrequency EPR spectrometers have been described for imaging applications with small samples. In the present work, we show the first two-dimensional image obtained at 220 MHz on a large phantom (40 ml) that simulates typical conditions of in vivo EPR imaging. This pulsed EPR apparatus has the potential to make the time required for three-dimensional imaging compatible with the biological half-life of normally used paramagnetic probes.
Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Animales , Fenómenos Biofísicos , Biofisica , Espectroscopía de Resonancia por Spin del Electrón/estadística & datos numéricos , Análisis de Fourier , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Ondas de Radio , RatasRESUMEN
The use of pH-sensitive nitroxides, in conjunction with low-frequency EPR, offers a unique opportunity for non-invasive assessment of pH values (in the range 0 to 14) in living animals. In the present study, we have investigated the potential use of pH-sensitive nitroxide free radicals in conjunction with EPR imaging techniques at low and very low frequencies (280 MHz-2.1 GHz). In particular, we have measured the hyperfine splitting (hfs) of a pH-sensitive probe at three different EPR frequencies: 280 MHz, 1.1 GHz and 2.1 GHz. We have also developed EPR imaging experiments with phantoms simulating in vivo conditions, using pH-sensitive probes at 280 MHz (spatial-spatial) and 1.1 GHz (spectral-spatial). Finally, we discuss the actual sensitivity/resolution limits of the EPR imaging techniques at low frequencies. Practical applications of this method in the biomedical field are suggested for the continuous and non-invasive localization of pH in vivo.
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Espectroscopía de Resonancia por Spin del Electrón/métodos , Concentración de Iones de Hidrógeno , Animales , Fenómenos Biofísicos , Biofisica , Radicales Libres/metabolismo , Modelos Biológicos , Óxidos de Nitrógeno/metabolismo , Fantasmas de Imagen , Ondas de Radio , Ratas , Marcadores de SpinRESUMEN
A cylindrical 16-pole electromagnet (EM) for electron paramagnetic resonance imaging (EPRI) and low-field magnetic resonance imaging (MRI) has been designed by means of two-dimensional and three-dimensional (3-D) finite element analysis (FEA). The use of an automatic procedure that combines FEA with a minimization routine allowed the optimization of the design, in order to improve the homogeneity along the axis of the EM. A prototype has been built by using electrical steel sheets that were cut by laser; this solution reduced significantly the manufacturing cost. The EM operates with a maximum flux density, in the bore, of 0.08 T and has a homogeneity along the axis of about 40 parts per million (ppm) in a spherical region 10 cm in diameter. It generates the main field and two of the three field gradients required in the 3-D image reconstruction. Good agreement was found between the results of simulation and the measured values.
Asunto(s)
Fenómenos Electromagnéticos , Imagen por Resonancia Magnética/instrumentación , Diseño de Equipo , Modelos BiológicosRESUMEN
Radiofrequency continuous wave EPR spectrometers for detecting and localizing free radicals in vivo in samples of 50-100 g have been developed. The main limitation of these EPR instruments is the slow acquisition time, and a sensible improvement is expected by the adoption of pulsed EPR techniques. We present here a Fourier transform EPR spectrometer operating at 220 MHz suitable for large volume samples (up to 50 ml). A detailed description of the transmitter and receiver sections, including the EPR resonator, is given. Representative free induction decay data obtained from a sample with a relaxation time of about 900 ns are reported. Copyright 1998 Academic Press.