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1.
Data Brief ; 48: 109109, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37122929

RESUMO

The CAMCATT-AI4GEO extensive field experiment took place in Toulouse, a city in the southwest of France, from 14th to 25th June 2021 (with complementary measurements performed on the 6 September 2021). Its main objective was the acquisition of a new reference dataset on an urban site to support the development and validation of data products from the future thermal infrared (TIR) satellite missions such as TRISHNA (CNES/ISRO), LSTM (ESA) and SBG (NASA). With their high spatial (between 30-60m) and temporal (2-3 days) resolutions, the future TIR satellite data will allow a better investigation of the urban climate at the neighbourhood scale. However, in order to validate the future products of these missions such as LST, air temperature, comfort index and Urban Heat Island (UHI), there is a need to accurately characterise the organisation of the city in terms of 3D geometry, spectral optical properties and both land surface temperature and emissivity (LST and LSE) at several scales. In this context, the CAMCATT-AI4GEO field campaign provides a set of airborne VISNIR-SWIR (Visible Near InfraRed - ShortWave InfraRed) hyperspectral imagery, multispectral thermal infrared (TIR) imagery and 3D LiDAR acquisitions, together with a variety of ground data collected, for some of them, simultaneously to the flight. The ground dataset includes surface reflectance measured spectrally with ASD spectroradiometers and in six spectral bands spreading from shortwave to thermal infrared and for two viewing angles with a SOC410-DHR handheld reflectometer. It is completed with LST and LSE retrieved from thermal infrared radiance acquired in six spectral bands with CIMEL radiometers. It also includes meteorological data coming from four radio soundings (one of which was taken during the flight), data routinely collected at the Blagnac airport reference station as well as air temperature and humidity acquired using instrumented cars following two different itineraries. In addition, a link is provided to access the data routinely collected by the network of weather stations set up by Toulouse Metropole in the city and its surroundings. This data paper describes this new reference urban dataset which can be useful for many applications such as calibration/validation of at-surface radiance, LST and LSE data products as well as higher level products such as air temperature or comfort index. It also provides valuable opportunities for other applications in urban climate studies, such as supporting the validation of microclimate models.

2.
Radiat Prot Dosimetry ; 198(1-2): 37-43, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35034129

RESUMO

The contribution of scattered neutrons is inevitable in neutron calibration facilities. This contribution complicates the measurements of neutron radiation, therefore, it should be estimated to correct the response of neutron probe instruments. In the present work, Monte Carlo simulation was performed for a neutron calibration bunker using the MCNP-4C code. This simulation aimed to calculate the contribution ratio of scattered neutrons to the neutron field. To simulate the neutron field, 241Am-Be neutron source defined in the ISO 8529-1 was used. The results of the simulation reported in this work were found to be consistent with those found experimentally in previous work. Additionally, the distribution of both the ambient dose equivalent rate and the contribution ratio of scattered neutrons in the bunker were mapped using this simulation.


Assuntos
Amerício , Nêutrons , Amerício/análise , Calibragem , Simulação por Computador , Método de Monte Carlo , Doses de Radiação , Radiometria/métodos
3.
Musculoskelet Surg ; 105(1): 61-67, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31894473

RESUMO

PURPOSE: The purpose of this work is to report mid- to long-term clinical results, recurrence rates and instability following surgery to repair anterior dislocation of the shoulder by the remplissage technique. METHODS: This was a retrospective case series at a single center with patients with anterior shoulder instability that received surgery using the remplissage technique. Rowe questionnaire, instability complaints, recurrence episodes and return to sport were analyzed. RESULTS: Of all patients screened, 21 (92.3%) were enrolled and only 2 patients were lost to follow-up. The mean age of the patients at the time of surgery was 27.8y.o., and the mean number of dislocations before surgery was 3.2 episodes. The follow-up average was 83.8 months (range 28-126). No case of postoperative infection was observed. Two patients (9.5%) had recurrent shoulder instability and required reintervention after 18 and 48 months. The average final Rowe score was 92.9 (range 75-100). All patients that played sports before surgery returned to the sport, and 73.7% of them returned to the same activity level. CONCLUSION: The remplissage technique applied to repair anterior shoulder dislocation with humeral bone loss presents good results regarding clinical scores, shoulder stability and acceptable rates of return to sports, even in a mid- to long-term follow-up. LEVEL OF EVIDENCE: IV.


Assuntos
Lesões de Bankart , Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Artroscopia , Seguimentos , Humanos , Instabilidade Articular/cirurgia , Recidiva , Estudos Retrospectivos , Ombro , Luxação do Ombro/diagnóstico por imagem , Luxação do Ombro/cirurgia
4.
Vet Med Int ; 2018: 4234791, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050673

RESUMO

Understanding the socioecology of domestic dog populations is essential for effective disease control, especially canine rabies. In Morocco, since 1986, the control efforts and plans put in place by the government have failed to eradicate this disease; this is because the management of the canine population was not taken into account during the establishment of these plans. It is against the background that this study was designed to estimate the dog population and determine its socioecological characteristics, as well as investigate the attitude of the inhabitants towards the dogs. A stratified random sampling was conducted using a structured questionnaire from May to December 2016. A total of 1931 households were interviewed, comprising 27.4% in urban areas and 72.6% in rural areas. A total of 3719 dogs were counted alongside a human population of 11302 for a dog : human ratio of 1 : 2.42 in rural areas and 1 : 46.58 in urban areas. The majority of dogs (92%) in rural areas were not vaccinated against rabies. In urban areas, about 88.5% were vaccinated against rabies. In addition, 78.5% of dogs in rural areas were free roaming, with more than 53% of births being abandoned by their owners, resulting in a large stray and feral dog population and increasing the potential for continued transmission of rabies virus. There was strong association between breed and rabies vaccination (p<0.05) and confinement with body condition score.

5.
Radiat Prot Dosimetry ; 179(2): 179-183, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29145639

RESUMO

Estimation of radiation intake and internal dose can be carried out through direct or indirect measurements during routine or special monitoring program. In case of Iodine-131 contamination, direct measurements, such as thyroid counting, are fast and efficient to give quick results. Generally, the calculation method implements suitable values for known parameters whereas default values are used if no information is available. However, in view to avoid significant discrepancies, IDEAS guidelines put in route a comprehensive method to evaluate the monitoring data for one and different types of monitoring. This article deals with a case of internal contamination of a worker who inhaled aerosols containing 131I during the production of radiopharmaceuticals. The interpretation of data obtained was done by following IDEAS guidelines.


Assuntos
Aerossóis , Radioisótopos do Iodo/análise , Exposição Ocupacional/análise , Doses de Radiação , Monitoramento de Radiação/métodos , Compostos Radiofarmacêuticos/análise , Glândula Tireoide/efeitos da radiação , Humanos , Proteção Radiológica/métodos , Síria
6.
Remote Sens Environ ; 193: 257-273, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-29743730

RESUMO

Two satellites are currently monitoring surface soil moisture (SM) using L-band observations: SMOS (Soil Moisture and Ocean Salinity), a joint ESA (European Space Agency), CNES (Centre national d'études spatiales), and CDTI (the Spanish government agency with responsibility for space) satellite launched on November 2, 2009 and SMAP (Soil Moisture Active Passive), a National Aeronautics and Space Administration (NASA) satellite successfully launched in January 2015. In this study, we used a multilinear regression approach to retrieve SM from SMAP data to create a global dataset of SM, which is consistent with SM data retrieved from SMOS. This was achieved by calibrating coefficients of the regression model using the CATDS (Centre Aval de Traitement des Données) SMOS Level 3 SM and the horizontally and vertically polarized brightness temperatures (TB) at 40° incidence angle, over the 2013 - 2014 period. Next, this model was applied to SMAP L3 TB data from Apr 2015 to Jul 2016. The retrieved SM from SMAP (referred to here as SMAP_Reg) was compared to: (i) the operational SMAP L3 SM (SMAP_SCA), retrieved using the baseline Single Channel retrieval Algorithm (SCA); and (ii) the operational SMOSL3 SM, derived from the multiangular inversion of the L-MEB model (L-MEB algorithm) (SMOSL3). This inter-comparison was made against in situ soil moisture measurements from more than 400 sites spread over the globe, which are used here as a reference soil moisture dataset. The in situ observations were obtained from the International Soil Moisture Network (ISMN; https://ismn.geo.tuwien.ac.at/) in North of America (PBO_H2O, SCAN, SNOTEL, iRON, and USCRN), in Australia (Oznet), Africa (DAHRA), and in Europe (REMEDHUS, SMOSMANIA, FMI, and RSMN). The agreement was analyzed in terms of four classical statistical criteria: Root Mean Squared Error (RMSE), Bias, Unbiased RMSE (UnbRMSE), and correlation coefficient (R). Results of the comparison of these various products with in situ observations show that the performance of both SMAP products i.e. SMAP_SCA and SMAP_Reg is similar and marginally better to that of the SMOSL3 product particularly over the PBO_H2O, SCAN, and USCRN sites. However, SMOSL3 SM was closer to the in situ observations over the DAHRA and Oznet sites. We found that the correlation between all three datasets and in situ measurements is best (R > 0.80) over the Oznet sites and worst (R = 0.58) over the SNOTEL sites for SMAP_SCA and over the DAHRA and SMOSMANIA sites (R= 0.51 and R= 0.45 for SMAP_Reg and SMOSL3, respectively). The Bias values showed that all products are generally dry, except over RSMN, DAHRA, and Oznet (and FMI for SMAP_SCA). Finally, our analysis provided interesting insights that can be useful to improve the consistency between SMAP and SMOS datasets.

7.
Appl Radiat Isot ; 113: 5-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27108068

RESUMO

Personal monitoring programs for workers handling radioactive materials are influenced by numerous factors as the measurements of radioactivity in tissues or/and in excreta can be carried out using different techniques. This paper summaries the basic procedures needed for accurate and fast measurement of different radionuclides like (235)U, (234)U, (238)U, (226)Ra, (210)Po, (131)I, (99m)Tc, (134)Cs, (137)Cs, (57)Co, (58)Co, and (60)Co. Overviews of in vitro and in vivo monitoring methods are provided as well as methods used to calculate detection limits and internal radiation dose. For the radionuclides of interest, in vivo and in vitro detection limits were converted into committed effective doses to evaluate the applicability and limitations of the systems used at the laboratory. The results proved that the systems' sensitivity is suitable for use in routine monitoring of workers subject to risk of internal exposure from such radionuclides. Consequently, monitoring programs suggested by the Syrian internal dosimetry laboratory are suitable to detect committed effective doses even below 1mSv in most cases.


Assuntos
Exposição Ocupacional/análise , Exposição à Radiação/análise , Monitoramento de Radiação/métodos , Radioisótopos/análise , Partículas alfa , Raios gama , Humanos , Limite de Detecção , Imagens de Fantasmas , Doses de Radiação , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/estatística & dados numéricos , Radioisótopos/urina , Síria , Glândula Tireoide/efeitos da radiação
8.
Appl Radiat Isot ; 82: 370-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24184740

RESUMO

Two methods for determination of internal dose due to (131)I intake during the preparation and handling of iodine radiopharmaceutical products have been compared. The first method was based on the measurement of (131)I in 24-hour urine samples while the second method was based on the measurement in vivo of (131)I in thyroid. The results have shown that urine analysis method can be used as a screening test but not for internal dose assessment of exposed workers. Thyroid monitoring method was found to be more reliable and accurate method for assessing internal dose from (131)I intake. In addition, the assessed internal dose showed that the annual internal effective dose for some workers was below 1 mSv with no risk classification, whereas the results of other group of workers were between 1 and 6 mSv with low risk classification. Only one worker reached 7.66 mSv with high risk classification; and this worker must be monitored individually.


Assuntos
Radioisótopos do Iodo/efeitos adversos , Radioisótopos do Iodo/análise , Exposição Ocupacional , Monitoramento de Radiação/métodos , Compostos Radiofarmacêuticos/efeitos adversos , Compostos Radiofarmacêuticos/análise , Calibragem , Humanos , Imagens de Fantasmas , Doses de Radiação , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/estatística & dados numéricos , Fatores de Risco , Software , Espectrometria gama/instrumentação , Espectrometria gama/estatística & dados numéricos , Glândula Tireoide/efeitos da radiação
9.
Radiat Prot Dosimetry ; 157(3): 310-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23782905

RESUMO

This paper describes a personal-computer-based software, REMAS, which helps users to estimate intake activity and resulting internal doses for all radionuclides existing in (International Commission on Radiological Protection) ICRP 78 and other important elements. In addition to its use in internal dose calculations, it facilitates management of data of monitored persons who are occupationally exposed to unsealed radioactive substances. Furthermore, REMAS offers the possibility to generate different reports of results. The program is suitable for laboratories working in the field of assessment of occupational intake and also for users of radioactive material who are routinely monitored. REMAS, which is bilingual program (English and Arabic), was built with GUI environment and was developed using Microsoft FoxPro. It runs on Microsoft Windows XP operating systems.


Assuntos
Exposição Ambiental/análise , Armazenamento e Recuperação da Informação , Exposição Ocupacional/análise , Monitoramento de Radiação , Proteção Radiológica , Humanos , Doses de Radiação , Lesões por Radiação/prevenção & controle
10.
Br J Neurosurg ; 27(4): 526-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23428147

RESUMO

A 26-year-old male presented with a mild confusion and hemianopsia after traumatic brain injury. Cerebral CT-scan revealed a 62.5 cm(3) left occipital extradural haematoma (EDH). Although conventional neurosurgical management would have been to evacuate the haematoma, a conservative strategy was preferred, and the patient made a total recovery.


Assuntos
Cavidades Cranianas/lesões , Hematoma Epidural Craniano/terapia , Adulto , Lesões Encefálicas/complicações , Gerenciamento Clínico , Escala de Coma de Glasgow , Hematoma Epidural Craniano/etiologia , Humanos , Masculino , Lobo Occipital/patologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
J Mater Chem B ; 1(10): 1381-1396, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32260777

RESUMO

Inorganic nanoparticles have become the focus of modern materials science due to their potential technological importance, particularly in bionanotechnology, which stems from their unique physical properties including size-dependent optical, magnetic, electronic, and catalytic properties. The present article provides an overview on the currently used individual inorganic nanoparticles for in vitro biomedical domains. These inorganic nanoparticles include iron oxides, gold, silver, silica, quantum dots (QDs) and second harmonic generation (SHG) particles. For each of these interesting nanoparticles, the main issues starting from preparation up to bio-related applications are presented.

12.
Neurochirurgie ; 58(6): 341-5, 2012 Dec.
Artigo em Francês | MEDLINE | ID: mdl-22770767

RESUMO

BACKGROUND AND PURPOSE: Paragangliomas of the cauda equina are rare tumors. The standard treatment is surgical resection. Our study aims to compare our clinical, radiological, prognostic data to the literature and to offer management and follow-up recommendations. METHODS: In this retrospective study, six patients with paraganglioma of the cauda equina region were treated. Symptoms included radicular nerve pain and low back pain with occasional sphincter dysfunction and motor deficit. MRI showed well-circumscribed lesions with homogeneous enhancement following gadolinium injection. Treatment involved complete surgical resection of the tumor under electrophysiological control. In addition to the characteristics of the tumor, we assessed operating results as well as postoperative morbidity and follow-up. RESULTS: All patients had complete removal of the tumor, which required in most cases the resection of the carrying root. The intervention allowed a regression of the initial symptoms, with possible postoperative regressive sphincter disorders. Clinical and radiological follow-up (19 months on average), showed no tumor recurrence. CONCLUSIONS: The reference treatment of these tumors is complete surgical resection, usually requiring the sacrifice of the carrying nerve root. Intra-operative nerve roots stimulation is recommended to reduce the risk of motor deficit linked to this radical treatment. A long-term clinical and radiological follow-up is recommended.


Assuntos
Cauda Equina/cirurgia , Eletrodiagnóstico/métodos , Monitorização Intraoperatória/métodos , Paraganglioma/cirurgia , Neoplasias do Sistema Nervoso Periférico/cirurgia , Adulto , Idoso , Cauda Equina/patologia , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias/prevenção & controle , Dor Lombar/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neurilemoma/diagnóstico , Paraganglioma/complicações , Paraganglioma/diagnóstico por imagem , Paraganglioma/patologia , Traumatismos dos Nervos Periféricos/prevenção & controle , Neoplasias do Sistema Nervoso Periférico/complicações , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/patologia , Polirradiculopatia/etiologia , Radiografia , Estudos Retrospectivos , Raízes Nervosas Espinhais/patologia , Raízes Nervosas Espinhais/fisiopatologia , Raízes Nervosas Espinhais/cirurgia , Incontinência Urinária por Estresse/etiologia
13.
Int J Lab Hematol ; 33(1): 1-18, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21054811

RESUMO

INTRODUCTION: Despite increasing evidence on the roles of aspirin and clopidogrel in decreasing morbidity and mortality from cardiovascular disease, resistance to therapy remains an emerging clinical entity. The aim of this review was to revisit current knowledge of the mechanisms, laboratory evaluation, clinical impact and management of resistance to aspirin and clopidogrel therapy. METHODS: Potentially relevant studies were identified from an electronic search of MEDLINE and PubMed databases. There were no language or publication year restrictions. References in published articles were also reviewed. RESULTS: Several definitions for resistance have been set, and various laboratory testing modalities are available. The pathophysiological mechanisms remain poorly understood; yet, several extrinsic, intrinsic and genetic factors are described. The clinical implications of this phenomenon are alarming and warrant concern. Management is currently limited to dosing alteration and introduction of other antiplatelet agents. CONCLUSION: Data from ongoing and future studies are awaited to better understand this entity and to highlight the most appropriate treatment strategies.


Assuntos
Aspirina/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Resistência a Medicamentos , Ticlopidina/análogos & derivados , Aspirina/farmacologia , Clopidogrel , Humanos , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico
14.
Neurochirurgie ; 56(5): 401-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20591451

RESUMO

Extradural meningiomas account for approximately 7% of all spinal meningiomas and are most commonly located in the thoracic spine. Although rare, they should be included in the differential diagnosis of an extradural contrast-enhancing mass. Prognosis depends greatly on the extent of surgical resection. If considered safe, complete resection should be attempted to decrease the risk of recurrence. We report a case of spinal epidural meningioma diagnosed in an elderly woman complaining of right cervicobrachial pain of several years duration, associated with diffuse paresthesia and permanent numbness of her right index finger. The surgical removal of the tumor was incomplete because of the deep lateral extension of the lesion.


Assuntos
Neoplasias Epidurais , Meningioma , Idoso , Vértebras Cervicais , Neoplasias Epidurais/diagnóstico , Neoplasias Epidurais/cirurgia , Feminino , Humanos , Meningioma/diagnóstico , Meningioma/cirurgia , Vértebras Torácicas
15.
Q J Nucl Med Mol Imaging ; 51(4): 343-51, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17538523

RESUMO

AIM: Targeted radionuclide therapy applications require the use of small animals for preclinical experiments. Accurate dose estimation is needed in such animals to explore and analyze the toxicity of injected radiopharmaceuticals. We developed two numerical models to allow for a more accurate mouse dosimetry. METHODS: A frozen nude mouse (30 g) was sliced and digital photographs were taken during the operation. More than 30 organs and tissues were identified and manually segmented. A digital (voxel-based) and a mathematical model were constructed from the segmented images. Important organs were simulated as radiation sources using the Monte-Carlo code MCNP4C. Mono-energetic photons from 0.005 to 2 MeV, and monoenergetic electrons from 0.1 to 2.5 MeV were simulated. Activity was supposed to be uniform in all source organs. RESULTS: Results from monoenergetic emissions were integrated over emission spectra. Radionuclide S-factors (Gy/Bq.s) were calculated by taking into account both electron and photon contributions. A comparison of the results obtained with either a voxel-based or mathematical model was carried out. The voxel-based model was then used to revise dosimetric results, obtained previously under the assumption that all emitted energy was absorbed locally. For (188)Re, the self-absorbed doses in xenografted tumors were 39-69% lower than that obtained by assuming local energy deposition. CONCLUSION: The voxel-based models represent more realistic anatomic approach. The rapid advancement of computer science and new features added to Monte-Carlo codes permit considerable reduction of computational run time. Cross-doses should not be neglected when medium to high energy beta emitters are being used for preclinical experiments on mice.


Assuntos
Modelos Animais de Doenças , Modelos Biológicos , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia/métodos , Contagem Corporal Total/métodos , Animais , Carga Corporal (Radioterapia) , Simulação por Computador , Camundongos , Camundongos Nus , Método de Monte Carlo , Neoplasias/fisiopatologia , Dosagem Radioterapêutica , Eficiência Biológica Relativa
16.
Phys Med Biol ; 52(4): 1013-25, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17264367

RESUMO

Murine models are useful for targeted radiotherapy pre-clinical experiments. These models can help to assess the potential interest of new radiopharmaceuticals. In this study, we developed a voxel-based mouse for dosimetric estimates. A female nude mouse (30 g) was frozen and cut into slices. High-resolution digital photographs were taken directly on the frozen block after each section. Images were segmented manually. Monoenergetic photon or electron sources were simulated using the MCNP4c2 Monte Carlo code for each source organ, in order to give tables of S-factors (in Gy Bq-1 s-1) for all target organs. Results obtained from monoenergetic particles were then used to generate S-factors for several radionuclides of potential interest in targeted radiotherapy. Thirteen source and 25 target regions were considered in this study. For each source region, 16 photon and 16 electron energies were simulated. Absorbed fractions, specific absorbed fractions and S-factors were calculated for 16 radionuclides of interest for targeted radiotherapy. The results obtained generally agree well with data published previously. For electron energies ranging from 0.1 to 2.5 MeV, the self-absorbed fraction varies from 0.98 to 0.376 for the liver, and from 0.89 to 0.04 for the thyroid. Electrons cannot be considered as 'non-penetrating' radiation for energies above 0.5 MeV for mouse organs. This observation can be generalized to radionuclides: for example, the beta self-absorbed fraction for the thyroid was 0.616 for I-131; absorbed fractions for Y-90 for left kidney-to-left kidney and for left kidney-to-spleen were 0.486 and 0.058, respectively. Our voxel-based mouse allowed us to generate a dosimetric database for use in preclinical targeted radiotherapy experiments.


Assuntos
Rim/efeitos da radiação , Método de Monte Carlo , Radioisótopos/farmacocinética , Radiometria/métodos , Baço/efeitos da radiação , Glândula Tireoide/efeitos da radiação , Animais , Carga Corporal (Radioterapia) , Transferência Linear de Energia , Camundongos , Camundongos Nus , Eficiência Biológica Relativa , Processamento de Sinais Assistido por Computador , Contagem Corporal Total
17.
Phys Med Biol ; 51(3): 601-16, 2006 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-16424584

RESUMO

Dosimetric studies are necessary for all patients treated with targeted radiotherapy. In order to attain the precision required, we have developed Oedipe, a dosimetric tool based on the MCNPX Monte Carlo code. The anatomy of each patient is considered in the form of a voxel-based geometry created using computed tomography (CT) images or magnetic resonance imaging (MRI). Oedipe enables dosimetry studies to be carried out at the voxel scale. Validation of the results obtained by comparison with existing methods is complex because there are multiple sources of variation: calculation methods (different Monte Carlo codes, point kernel), patient representations (model or specific) and geometry definitions (mathematical or voxel-based). In this paper, we validate Oedipe by taking each of these parameters into account independently. Monte Carlo methodology requires long calculation times, particularly in the case of voxel-based geometries, and this is one of the limits of personalized dosimetric methods. However, our results show that the use of voxel-based geometry as opposed to a mathematically defined geometry decreases the calculation time two-fold, due to an optimization of the MCNPX2.5e code. It is therefore possible to envisage the use of Oedipe for personalized dosimetry in the clinical context of targeted radiotherapy.


Assuntos
Radiometria/métodos , Radioterapia/métodos , Simulação por Computador , Estudos de Avaliação como Assunto , Humanos , Imageamento por Ressonância Magnética , Modelos Anatômicos , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Planejamento da Radioterapia Assistida por Computador , Reprodutibilidade dos Testes , Software
18.
J Sports Med Phys Fitness ; 45(1): 13-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16208285

RESUMO

AIM: The objective of the present study was to determine oxygen uptake (VO(2)) and percentage of maximum oxygen uptake (%VO2max) in obese and non-obese adolescents during various activities in standardised conditions, and the corresponding %VO2max in free-living conditions. METHODS: Twenty-seven obese and 50 non-obese adolescents aged 12 to 16 years participated in this study. Body composition was assessed by bioelectrical impedance analysis and dual energy X-ray absorptiometry (DXA), VO2max by treadmill tests, VO2 corresponding to various activities by whole body calorimetry, and time and % VO2max corresponding to various activities in free-living conditions using the heart-rate recording method and a physical activity diary. RESULTS: VO2max (l/min) was 27.4% higher in obese than in non-obese subjects (p<0.001), but not significantly different after adjustment for fat-free mass (FFM). In the whole body calorimeters, with the same activity program, % VO2max corresponding to sleep and sedentary activities were lower in obese than in non-obese girls (-15.1% and -12.3%, p<0.05), but not significantly different between obese and non-obese boys. However, walking at 4-5-6 km/h corresponded to 47-59% and 71% of VO2max, respectively, in obese, and 34-41% and 48% of VO2max in non-obese subjects (p<0.001). In free-living conditions, moderate physical activities and sports corresponded to 52% vs 35%, and 39% vs 51% of VO2max, respectively, in obese and non-obese adolescents. CONCLUSIONS: In standardised conditions %VO2max did not correspond to the same type of physical activity in obese compared to non-obese adolescents. Consequently, % VO2max is inadequate for comparing the types of physical activities of obese and non-obese adolescents in free-living conditions.


Assuntos
Atividade Motora/fisiologia , Obesidade/fisiopatologia , Consumo de Oxigênio/fisiologia , Absorciometria de Fóton , Adolescente , Análise de Variância , Composição Corporal , Criança , Impedância Elétrica , Metabolismo Energético , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino
19.
J Neurol Neurosurg Psychiatry ; 76(6): 845-51, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15897509

RESUMO

OBJECTIVES: Despite the growing use of intraoperative functional mapping in supratentorial low grade glioma (LGG) surgery, few studies have compared series of patients operated on without and with direct electrical stimulation (DES) by the same team. The present study compared the rate of LGG surgery performed in eloquent areas, the rate of postoperative sequelae, and the quality of resection during two consecutive periods in the same department-the first without and the second with the use of intraoperative electrophysiology. METHODS: Between 1985 and 1996, 100 patients harbouring a supratentorial LGG underwent surgery with no functional mapping (S1). Between 1996 and 2003, 122 patients were operated on in the same department for a supratentorial LGG using intraoperative cortico-subcortical DES (S2). RESULTS: Comparison between the two series showed that 35% of LGGs were operated on in eloquent areas in S1 versus 62% in S2 (p<0.0001), with 17% severe permanent deficits in S1 versus 6.5% in S2 (p<0.019). On postoperative MRI, 37% of resections were subtotal and 6% total in S1 versus 50.8% and 25.4%, respectively, in S2 (p<0.001). In both groups, survival was significantly related to the quality of resection. CONCLUSIONS: The results of the present study allow, for the first time, quantification of the contribution of intraoperative DES in LGG resection. Indeed, the use of this method leads to the extension of indications of LGG surgery within eloquent areas; to a decrease in the risk of sequelae; and to improvement of the quality of tumour resection, with an impact on survival.


Assuntos
Mapeamento Encefálico/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Glioma/patologia , Glioma/cirurgia , Cuidados Intraoperatórios , Imageamento por Ressonância Magnética , Procedimentos Neurocirúrgicos/instrumentação , Adolescente , Adulto , Idoso , Estimulação Elétrica/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
20.
Acta Neurochir (Wien) ; 146(4): 403-6; discussion 406, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15057536

RESUMO

We hereby report the endovascular management of a posttraumatic caroticocavernous fistula combined with an occlusive ipsilateral carotid dissection; this was successfully managed by a contra-lateral arterial approach via the anterior communicating artery.


Assuntos
Dissecação da Artéria Carótida Interna/etiologia , Dissecação da Artéria Carótida Interna/terapia , Fístula Carótido-Cavernosa/terapia , Embolização Terapêutica/métodos , Ferimentos por Arma de Fogo/complicações , Fístula Carótido-Cavernosa/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Resultado do Tratamento
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