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  1. Article ; Online: First experimental demonstration of real-time neutron capture discrimination in helium and carbon ion therapy.

    Kielly, Marissa / Caracciolo, Anita / Chacon, Andrew / Vohradsky, James / Di Vita, Davide / Hamato, Akram / Tashima, Hideaki / Franklin, Daniel R / Yamaya, Taiga / Rosenfeld, Anatoly / Carminati, Marco / Fiorini, Carlo / Guatelli, Susanna / Safavi-Naeini, Mitra

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 2601

    Abstract: This work provides the first experimental proof of an increased neutron capture photon signal following the introduction of boron to a PMMA phantom during helium and carbon ion therapies in Neutron Capture Enhanced Particle Therapy (NCEPT). NCEPT ... ...

    Abstract This work provides the first experimental proof of an increased neutron capture photon signal following the introduction of boron to a PMMA phantom during helium and carbon ion therapies in Neutron Capture Enhanced Particle Therapy (NCEPT). NCEPT leverages [Formula: see text]B neutron capture, leading to the emission of detectable 478 keV photons. Experiments were performed at the Heavy Ion Medical Accelerator in Chiba, Japan, with two Poly(methyl methacrylate) (PMMA) targets, one bearing a boron insert. The BeNEdiCTE gamma-ray detector measured an increase in the 478 keV signal of 45 ± 7% and 26 ± 2% for carbon and helium ion irradiation, respectively. Our Geant4 Monte Carlo simulation model, developed to investigate photon origins, found less than 30% of detected photons originated from the insert, while boron in the detector's circuit boards contributed over 65%. Further, the model investigated detector sensitivity, establishing its capability to record a 10% increase in 478 keV photon detection at a target [Formula: see text]B concentration of 500 ppm using spectral windowing alone, and 25% when combined with temporal windowing. The linear response extended to concentrations up to 20,000 ppm. The increase in the signal in all evaluated cases confirm the potential of the proposed detector design for neutron capture quantification in NCEPT.
    Language English
    Publishing date 2024-01-31
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-52162-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: A Monte Carlo model of the Dingo thermal neutron imaging beamline.

    Jakubowski, Klaudiusz / Chacon, Andrew / Tran, Linh T / Stopic, Attila / Garbe, Ulf / Bevitt, Joseph / Olsen, Scott / Franklin, Daniel R / Rosenfeld, Anatoly / Guatelli, Susanna / Safavi-Naeini, Mitra

    Scientific reports

    2023  Volume 13, Issue 1, Page(s) 17415

    Abstract: In this study, we present a validated Geant4 Monte Carlo simulation model of the Dingo thermal neutron imaging beamline at the Australian Centre for Neutron Scattering. The model, constructed using CAD drawings of the entire beam transport path and ... ...

    Abstract In this study, we present a validated Geant4 Monte Carlo simulation model of the Dingo thermal neutron imaging beamline at the Australian Centre for Neutron Scattering. The model, constructed using CAD drawings of the entire beam transport path and shielding structures, is designed to precisely predict the in-beam neutron field at the position at the sample irradiation stage. The model's performance was assessed by comparing simulation results to various experimental measurements, including planar thermal neutron distribution obtained in-beam using gold foil activation and [Formula: see text]B[Formula: see text]C-coated microdosimeters and the out-of-beam neutron spectra measured with Bonner spheres. The simulation results demonstrated that the predicted neutron fluence at the field's centre is within 8.1% and 2.1% of the gold foil and [Formula: see text]B[Formula: see text]C-coated microdosimeter measurements, respectively. The logarithms of the ratios of average simulated to experimental fluences in the thermal (E[Formula: see text] 0.414 eV), epithermal (0.414 eV < E[Formula: see text] 11.7 keV) and fast (E[Formula: see text] 11.7 keV) spectral regions were approximately - 0.03 to + 0.1, - 0.2 to + 0.15, and - 0.4 to + 0.2, respectively. Furthermore, the predicted thermal, epithermal and fast neutron components in-beam at the sample stage position constituted approximately 18%, 64% and 18% of the total neutron fluence.
    Language English
    Publishing date 2023-10-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-44035-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Microdosing, isotopic labeling, radiotracers and metabolomics: relevance in drug discovery, development and safety.

    Wotherspoon, Andrew Tl / Safavi-Naeini, Mitra / Banati, Richard B

    Bioanalysis

    2017  Volume 9, Issue 23, Page(s) 1913–1933

    Abstract: This review discusses the use of stable ( ...

    Abstract This review discusses the use of stable (
    MeSH term(s) Drug Discovery ; Isotope Labeling ; Metabolomics ; Pharmaceutical Preparations/chemistry ; Pharmaceutical Preparations/metabolism ; Positron-Emission Tomography ; Radiation Dosage ; Radiopharmaceuticals/chemistry ; Radiopharmaceuticals/metabolism ; Tomography, Emission-Computed, Single-Photon
    Chemical Substances Pharmaceutical Preparations ; Radiopharmaceuticals
    Language English
    Publishing date 2017-11-24
    Publishing country England
    Document type Journal Article ; Review
    ISSN 1757-6199
    ISSN (online) 1757-6199
    DOI 10.4155/bio-2017-0137
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Optimisation of monolithic nanocomposite and transparent ceramic scintillation detectors for positron emission tomography.

    Wilson, Keenan J / Alabd, Roumani / Abolhasan, Mehran / Safavi-Naeini, Mitra / Franklin, Daniel R

    Scientific reports

    2020  Volume 10, Issue 1, Page(s) 1409

    Abstract: High-resolution arrays of discrete monocrystalline scintillators used for gamma photon coincidence detection in PET are costly and complex to fabricate, and exhibit intrinsically non-uniform sensitivity with respect to emission angle. Nanocomposites and ... ...

    Abstract High-resolution arrays of discrete monocrystalline scintillators used for gamma photon coincidence detection in PET are costly and complex to fabricate, and exhibit intrinsically non-uniform sensitivity with respect to emission angle. Nanocomposites and transparent ceramics are two alternative classes of scintillator materials which can be formed into large monolithic structures, and which, when coupled to optical photodetector arrays, may offer a pathway to low cost, high-sensitivity, high-resolution PET. However, due to their high optical attenuation and scattering relative to monocrystalline scintillators, these materials exhibit an inherent trade-off between detection sensitivity and the number of scintillation photons which reach the optical photodetectors. In this work, a method for optimising scintillator thickness to maximise the probability of locating the point of interaction of 511 keV photons in a monolithic scintillator within a specified error bound is proposed and evaluated for five nanocomposite materials (LaBr
    Language English
    Publishing date 2020-01-29
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-020-58208-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Localisation of the Lines of Response in a Continuous Cylindrical Shell PET Scanner.

    Wilson, Keenan J / Alabd, Roumani / Abolhasan, Mehran / Franklin, Daniel R / Safavi-Naeini, Mitra

    Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference

    2019  Volume 2019, Page(s) 4844–4850

    Abstract: This work presents a technique for localising the endpoints of the lines of response in a PET scanner based on a continuous cylindrical shell scintillator. The technique is demonstrated by applying it to a simulation of a sensitivity-optimised continuous ...

    Abstract This work presents a technique for localising the endpoints of the lines of response in a PET scanner based on a continuous cylindrical shell scintillator. The technique is demonstrated by applying it to a simulation of a sensitivity-optimised continuous cylindrical shell PET system using two novel scintillator materials - a transparent ceramic garnet, GLuGAG:Ce, and a LuF
    MeSH term(s) Algorithms ; Ceramics ; Nanocomposites ; Phantoms, Imaging ; Polystyrenes ; Positron-Emission Tomography
    Chemical Substances Polystyrenes
    Language English
    Publishing date 2019-12-30
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2694-0604
    ISSN (online) 2694-0604
    DOI 10.1109/EMBC.2019.8856676
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Neutron Capture Enhances Dose and Reduces Cancer Cell Viability in and out of Beam During Helium and Carbon Ion Therapy.

    Howell, Nicholas / Middleton, Ryan J / Sierro, Frederic / Fraser, Benjamin H / Wyatt, Naomi A / Chacon, Andrew / Bambery, Keith R / Livio, Elle / Dobie, Christopher / Bevitt, Joseph J / Davies, Justin / Dosseto, Anthony / Franklin, Daniel R / Garbe, Ulf / Guatelli, Susanna / Hirayama, Ryoichi / Matsufuji, Naruhiro / Mohammadi, Akram / Mutimer, Karl /
    Rendina, Louis M / Rosenfeld, Anatoly B / Safavi-Naeini, Mitra

    International journal of radiation oncology, biology, physics

    2024  

    Abstract: Purpose: Neutron capture enhanced particle therapy (NCEPT) is a proposed augmentation of charged particle therapy that exploits thermal neutrons generated internally, within the treatment volume via nuclear fragmentation, to deliver a biochemically ... ...

    Abstract Purpose: Neutron capture enhanced particle therapy (NCEPT) is a proposed augmentation of charged particle therapy that exploits thermal neutrons generated internally, within the treatment volume via nuclear fragmentation, to deliver a biochemically targeted radiation dose to cancer cells. This work is the first experimental demonstration of NCEPT, performed using both carbon and helium ion beams with 2 different targeted neutron capture agents (NCAs).
    Methods and materials: Human glioblastoma cells (T98G) were irradiated by carbon and helium ion beams in the presence of NCAs [
    Results: Cells placed inside the treatment volume reached 10% survival by 2 Gy of carbon or 2 to 3 Gy of helium in the presence of NCAs compared with 5 Gy of carbon and 7 Gy of helium with no NCA. Cells placed adjacent to the treatment volume showed a dose-dependent decrease in cell growth when treated with NCAs, reaching 10% survival by 6 Gy of carbon or helium (to the treatment volume), compared with no detectable effect on cells without NCA. The mean thermal neutron fluence at the center of the SOBP was approximately 2.2 × 10
    Conclusions: The addition of NCAs to cancer cells during carbon and helium beam irradiation has a measurable effect on cell survival and growth in vitro. Through the capture of internally generated neutrons, NCEPT introduces the concept of a biochemically targeted radiation dose to charged particle therapy. NCEPT enables the established pharmaceuticals and concepts of neutron capture therapy to be applied to a wider range of deeply situated and diffuse tumors, by targeting this dose to microinfiltrates and cells outside of defined treatment regions. These results also demonstrate the potential for NCEPT to provide an increased dose to tumor tissue within the treatment volume, with a reduction in radiation doses to off-target tissue.
    Language English
    Publishing date 2024-03-11
    Publishing country United States
    Document type Journal Article
    ZDB-ID 197614-x
    ISSN 1879-355X ; 0360-3016
    ISSN (online) 1879-355X
    ISSN 0360-3016
    DOI 10.1016/j.ijrobp.2024.02.052
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  7. Article ; Online: Detection and discrimination of neutron capture events for NCEPT dose quantification.

    Chacon, Andrew / Kielly, Marissa / Rutherford, Harley / Franklin, Daniel R / Caracciolo, Anita / Buonanno, Luca / D'Adda, Ilenia / Rosenfeld, Anatoly / Guatelli, Susanna / Carminati, Marco / Fiorini, Carlo / Safavi-Naeini, Mitra

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 5863

    Abstract: Neutron Capture Enhanced Particle Therapy (NCEPT) boosts the effectiveness of particle therapy by capturing thermal neutrons produced by beam-target nuclear interactions in and around the treatment site, using tumour-specific [Formula: see text]B or [ ... ...

    Abstract Neutron Capture Enhanced Particle Therapy (NCEPT) boosts the effectiveness of particle therapy by capturing thermal neutrons produced by beam-target nuclear interactions in and around the treatment site, using tumour-specific [Formula: see text]B or [Formula: see text]Gd-based neutron capture agents. Neutron captures release high-LET secondary particles together with gamma photons with energies of 478 keV or one of several energies up to 7.94 MeV, for [Formula: see text]B and [Formula: see text]Gd, respectively. A key requirement for NCEPT's translation is the development of in vivo dosimetry techniques which can measure both the direct ion dose and the dose due to neutron capture. In this work, we report signatures which can be used to discriminate between photons resulting from neutron capture and those originating from other processes. A Geant4 Monte Carlo simulation study into timing and energy thresholds for discrimination of prompt gamma photons resulting from thermal neutron capture during NCEPT was conducted. Three simulated [Formula: see text] mm[Formula: see text] cubic PMMA targets were irradiated by [Formula: see text]He or [Formula: see text]C ion beams with a spread out Bragg peak (SOBP) depth range of 60 mm; one target is homogeneous while the others include [Formula: see text] mm[Formula: see text] neutron capture inserts (NCIs) of pure [Formula: see text]B or [Formula: see text]Gd located at the distal edge of the SOBP. The arrival times of photons and neutrons entering a simulated [Formula: see text] mm[Formula: see text] ideal detector were recorded. A temporal mask of 50-60 ns was found to be optimal for maximising the discrimination of the photons resulting from the neutron capture by boron and gadolinium. A range of candidate detector and thermal neutron shielding materials were simulated, and detections meeting the proposed acceptance criteria (i.e. falling within the target energy window and arriving 60 ns post beam-off) were classified as true or false positives, depending on their origin. The ratio of true/false positives ([Formula: see text]) was calculated; for targets with [Formula: see text]B and [Formula: see text]Gd NCIs, the detector materials which resulted in the highest [Formula: see text] were cadmium-shielded CdTe and boron-shielded LSO, respectively. The optimal irradiation period for both carbon and helium ions was 1 µs for the [Formula: see text]B NCI and 1 ms for the [Formula: see text]Gd NCI.
    MeSH term(s) Boron ; Cadmium Compounds ; Monte Carlo Method ; Neutrons ; Quantum Dots ; Tellurium
    Chemical Substances Cadmium Compounds ; Boron (N9E3X5056Q) ; Tellurium (NQA0O090ZJ) ; cadmium telluride (STG188WO13)
    Language English
    Publishing date 2022-04-07
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-09676-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: An inception network for positron emission tomography based dose estimation in carbon ion therapy.

    Rutherford, Harley / Saha Turai, Rohan / Chacon, Andrew / Franklin, Daniel R / Mohammadi, Akram / Tashima, Hideaki / Yamaya, Taiga / Parodi, Katia / Rosenfeld, Anatoly B / Guatelli, Susanna / Safavi-Naeini, Mitra

    Physics in medicine and biology

    2022  Volume 67, Issue 19

    Abstract: ... ...

    Abstract Objective
    MeSH term(s) Carbon/therapeutic use ; Heavy Ion Radiotherapy/methods ; Monte Carlo Method ; Phantoms, Imaging ; Polymethyl Methacrylate ; Positron-Emission Tomography/methods
    Chemical Substances Carbon (7440-44-0) ; Polymethyl Methacrylate (9011-14-7)
    Language English
    Publishing date 2022-09-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/ac88b2
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  9. Article ; Online: A simulation study of BrachyShade, a shadow-based internal source tracking system for HDR prostate brachytherapy.

    Alabd, Roumani / Safavi-Naeini, Mitra / Wilson, Keenan J / Rosenfeld, Anatoly B / Franklin, Daniel R

    Physics in medicine and biology

    2018  Volume 63, Issue 20, Page(s) 205019

    Abstract: This paper presents a simulation study of BrachyShade, a proposed internal source-tracking system for real time quality assurance in high dose rate prostate brachytherapy. BrachyShade consists of a set of spherical tungsten occluders located above a ... ...

    Abstract This paper presents a simulation study of BrachyShade, a proposed internal source-tracking system for real time quality assurance in high dose rate prostate brachytherapy. BrachyShade consists of a set of spherical tungsten occluders located above a pixellated silicon photodetector. The source location is estimated by minimising the mean squared error between a parametric model of the shadow image and acquired images of the shadows projected on the detector plane. A novel algorithm is finally employed to correct the systemic error resulting from Compton scattering in the medium. The worst-case error obtained with BrachyShade for a 13.5 ms image acquisition is less than 1.3 mm in the most distant part of the treatment volume, while for 75% of source locations an error of less than 0.42 mm was achieved.
    MeSH term(s) Algorithms ; Brachytherapy/instrumentation ; Brachytherapy/methods ; Humans ; Male ; Models, Theoretical ; Prostatic Neoplasms/radiotherapy ; Quality Control ; Radiotherapy Dosage
    Language English
    Publishing date 2018-10-18
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/aae33d
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  10. Article ; Online: Opportunistic dose amplification for proton and carbon ion therapy via capture of internally generated thermal neutrons.

    Safavi-Naeini, Mitra / Chacon, Andrew / Guatelli, Susanna / Franklin, Daniel R / Bambery, Keith / Gregoire, Marie-Claude / Rosenfeld, Anatoly

    Scientific reports

    2018  Volume 8, Issue 1, Page(s) 16257

    Abstract: This paper presents Neutron Capture Enhanced Particle Therapy (NCEPT), a method for enhancing the radiation dose delivered to a tumour relative to surrounding healthy tissues during proton and carbon ion therapy by capturing thermal neutrons produced ... ...

    Abstract This paper presents Neutron Capture Enhanced Particle Therapy (NCEPT), a method for enhancing the radiation dose delivered to a tumour relative to surrounding healthy tissues during proton and carbon ion therapy by capturing thermal neutrons produced inside the treatment volume during irradiation. NCEPT utilises extant and in-development boron-10 and gadolinium-157-based drugs from the related field of neutron capture therapy. Using Monte Carlo simulations, we demonstrate that a typical proton or carbon ion therapy treatment plan generates an approximately uniform thermal neutron field within the target volume, centred around the beam path. The tissue concentrations of neutron capture agents required to obtain an arbitrary 10% increase in biological effective dose are estimated for realistic treatment plans, and compared to concentrations previously reported in the literature. We conclude that the proposed method is theoretically feasible, and can provide a worthwhile improvement in the dose delivered to the tumour relative to healthy tissue with readily achievable concentrations of neutron capture enhancement drugs.
    MeSH term(s) Boron/administration & dosage ; Boron Neutron Capture Therapy/instrumentation ; Boron Neutron Capture Therapy/methods ; Computer Simulation ; Dose-Response Relationship, Radiation ; Feasibility Studies ; Gadolinium/administration & dosage ; Heavy Ion Radiotherapy/instrumentation ; Heavy Ion Radiotherapy/methods ; Humans ; Isotopes/administration & dosage ; Models, Biological ; Monte Carlo Method ; Neoplasms/radiotherapy ; Neutrons ; Phantoms, Imaging ; Protons ; Radiotherapy Dosage ; Radiotherapy Planning, Computer-Assisted/methods
    Chemical Substances Boron-10 ; Gadolinium-157 ; Isotopes ; Protons ; Gadolinium (AU0V1LM3JT) ; Boron (N9E3X5056Q)
    Language English
    Publishing date 2018-11-02
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-018-34643-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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