As part of translational research projects, mice may be irradiated on radiobiology platforms such as the one at the ARRONAX cyclotron. Generally, these platforms do not feature an integrated imaging system. Moreover, in the context of ultra-high dose-rate radiotherapy (FLASH-RT), treatment planning should consider potential changes in the beam characteristics and internal movements in the animal.
View Article and Find Full Text PDFRadioactive particles often contain very high radioactivity concentrations and are widespread. They pose a potential risk to human health and the environment. Their detection, quantification, and characterization are crucial if we are to understand their impact.
View Article and Find Full Text PDFCesium-134 and -137 are prevalent, long-lived, radio-toxic contaminants released into the environment during nuclear accidents. Large quantities of insoluble, respirable Cs-bearing microparticles (CsMPs) were released into the environment during the Fukushima Daiichi nuclear accident. Monitoring for CsMPs in environmental samples is essential to understand the impact of nuclear accidents.
View Article and Find Full Text PDFPurpose: The ARRONAX cyclotron facility offers the possibility to deliver proton beams from low to ultra-high dose rates (UHDR). As a good control of the dosimetry is a prerequisite of UHDR experimentations, we evaluated in different conditions the usability and the dose rate dependency of several radiochromic films commonly used for dosimetry in radiotherapy.
Methods: We compared the dose rate dependency of three types of radiochromic films: GAFchromic™ EBT3 and GAFchromic™ EBT-XD (Ashland Inc.
Proton therapy (PRT) is an irradiation technique that aims at limiting normal tissue damage while maintaining the tumor response. To study its specificities, the ARRONAX cyclotron is currently developing a preclinical structure compatible with biological experiments. A prerequisite is to identify and control uncertainties on the ARRONAX beamline, which can lead to significant biases in the observed biological results and dose-response relationships, as for any facility.
View Article and Find Full Text PDFAim: The purpose of this work is to evaluate the precision with which the GEANT4 toolkit simulates the production of β emitters relevant for in-beam and real-time PET in proton therapy.
Background: An important evolution in proton therapy is the implementation of in-beam and real-time verification of the range of protons by measuring the correlation between the activity of β and dose deposition. For that purpose, it is important that the simulation of the various β emitters be sufficiently realistic, in particular for the N short-lived emitter that is required for efficient in-beam and real-time monitoring.
The characteristics of sudden infant death syndrome (SIDS) in the French region of Languedoc-Roussillon from 2003-2008 were examined in a retrospective study of two groups classified as unexplained sudden unexpected death in infancy (SUDI) (SIDS, n = 27) or explained SUDI (n = 22). The interval between the time the baby was last observed alive (time of last feed) and the discovery of death was evaluated. In SIDS, 67% (18/27) of deaths were discovered during the day (09:00-21:00 h) mostly within 4 h after feeding (66%).
View Article and Find Full Text PDFA previously healthy 4-year-old boy presented with typical measles and demonstrated lesions confined to basal ganglia. The clinical symptoms were an abrupt onset, impaired consciousness and mutism, extrapyramidal signs and severe neurovegetative dysfunction. No modification of the cerebrospinal fluid was observed; laboratory tests were all normal with the exception of a positive serologic test for measles.
View Article and Find Full Text PDFBackground: Severe central nervous system diseases, such as encephalitis, have been reported in association with Mycoplasma pneumoniae infections.
Case Report: After an ENT infection, a 9-year-old boy with Down's syndrome developed encephalitis revealed by an acute alteration in consciousness. Head computed tomography showed, after 2 weeks, an infiltration in the basal ganglia region.
A 1-month-old infant presented with a typical pattern of pyloric stenosis but US revealed an intense hyperechogenicity of the thickened pyloric muscle. Cholecystitis and pancreatitis were also present in this child. Familial hyperchylomicronemia was detected.
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