Publications by authors named "Maria Bellon"

Introduction: The purpose of this study was to investigate the systematic localization accuracy, treatment planning capability, and delivery accuracy of an integrated magnetic resonance imaging guided Linear Accelerator (MR-Linac) platform for stereotactic radiosurgery.

Materials And Methods: The phantom for the end-to-end test comprises three different compartments: a rectangular MR/CT target phantom, a Winston-Lutz cube, and a rectangular MR/CT isocenter phantom. Hidden target tests were performed at gantry angles of 0, 90, 180, and 270 degrees to quantify the systematic accuracy.

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The purpose of this study is to characterize the dosimetric properties and accuracy of a novel treatment platform (Edge radiosurgery system) for localizing and treating patients with frameless, image-guided stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT). Initial measurements of various components of the system, such as a comprehensive assessment of the dosimetric properties of the flattening filter-free (FFF) beams for both high definition (HD120) MLC and conical cone-based treatment, positioning accuracy and beam attenuation of a six degree of freedom (6DoF) couch, treatment head leakage test, and integrated end-to-end accuracy tests, have been performed. The end-to-end test of the system was performed by CT imaging a phantom and registering hidden targets on the treatment couch to determine the localization accuracy of the optical surface monitoring system (OSMS), cone-beam CT (CBCT), and MV imaging systems, as well as the radiation isocenter targeting accuracy.

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Background: Plantar ulcers, which commonly occur in leprosy patients, tend to recur increasing physical disability. The aim of this study is to identify both the bacteriological profile of these ulcers and the antibiotic susceptibility of the isolated bacteria.

Materials And Methods: 68 leprosy patients with chronic ulcers attending the in-patient department of Gambo General Hospital, West Arsi, were included in this study.

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The purpose of this study is to evaluate the overall accuracy of intensity-modulated radiation therapy (IMRT) and RapidArc delivery using both flattening filter (FF) and flattening filter-free (FFF) modalities based on test cases developed by AAPM Task Group 119. Institutional confidence limits (CLs) were established as the baseline for patient specific treatment plan quality assurance (QA). The effects of gantry range, gantry speed, leaf speed, dose rate, as well as the capability to capture intentional errors, were evaluated by measuring a series of Picket Fence (PF) tests using the electronic portal imaging device (EPID) and EBT3 films.

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The acquisition of high-quality, anatomic images is essential for the accurate delineation of tumor volumes and critical structures used for stereotactic radiosurgery (SRS) treatment planning. This study investigates the effect of CT slice thickness and field of view (FOV), i.e.

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Vaginal cuff dehiscence is a rare, but potentially serious complication after total hysterectomy. We report a case of vaginal cuff dehiscence after vaginal cuff brachytherapy. A 62 year old female underwent a robotic-assisted laparoscopic hysterectomy with bilateral salpingo-oophorectomy, and was found to have International Federation of Gynecology and Obstetrics (FIGO) 2009 stage IB endometrioid adenocarcinoma of the uterus.

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This study aimed to analyze how the prevalence and the distribution of dental caries influence the sample size in epidemiological surveys, and how much are the costs. Secondary data of oral health surveys in 12-year-old schoolchildren from Bauru in 1976, 1984, 1990, 1994, and 2001, and from Piracicaba in 2001 and 2005 were studied. Sample sizes were estimated taking into account the mean DMFT and standard deviation of each survey, establishing sampling errors of 1%, 2%, 5%, and 10%.

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The hepatic venous pressure gradient (HVPG) is the gold standard for assessing portal pressure and correlates with the occurrence of portal hypertension (PH)-related complications. Transient elastography (TE) is a new, highly accurate noninvasive technique, which enables us to evaluate hepatic fibrosis to detect advanced fibrosis and cirrhosis. We performed a hepatic haemodynamic study and TE in 38 HIV/HCV-coinfected patients.

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The objective of the present study was to analyse whether there is a relationship between the clinical severity at the time of starting transpyloric enteral nutrition (TEN) and the onset of digestive tract complications in critically ill children. Between May 2005 and December 2007, we performed a prospective, observational study with the participation of 209 critically ill children aged between 3 d and 17 years and who received TEN. The characteristics of the nutrition and its tolerance were compared with the paediatric risk of mortality (PRISM), the paediatric index of mortality (PIM) and the paediatric logistic organ dysfunction index (PELOD) at the time of starting the nutrition.

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Introduction: The development of resistance to antiretroviral therapy (ART) reduces the effectiveness of these drugs in HIV-infected children.

Methods: We performed a cross-sectional study in 86 vertically HIV-infected children, divided into four groups according to prior treatment: group 1: nucleoside reverse transcriptase inhibitor (NRTI), group 2: NRTI and non-nucleoside reverse transcriptase inhibitor (NNRTI), group 3: NRTI and protease inhibitor (PI), group 4: NRTI, NNRTI and PI.

Results: In group 1 (11 children), the median treatment duration was 35 months (26 to 108).

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Background: Antiretroviral treatment (ART) in children has special features and consequently, results obtained from clinical trials with antiretroviral drugs in adults may not be representative of children. Nelfinavir (NFV) is an HIV-1 Protease Inhibitor (PI) which has become as one of the first choices of PI for ART in children. We studied during a 3-year follow-up period the effects of highly active antiretroviral therapy with nelfinavir in vertically HIV-1 infected children.

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Background. Use of antiretroviral therapy has resulted in a decrease in morbidity and mortality rates in human immunodeficiency virus type 1 (HIV-1)-infected children.Methods.

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