Study of Bone Surface Absorbed Dose in Treatment of Bone Metastases via Selected Radiopharmaceuticals: Using MCNP4C Code and Available Experimental Data

2015 ◽  
Vol 30 (4) ◽  
pp. 174-181 ◽  
Author(s):  
Reza Bagheri ◽  
Hossein Afarideh ◽  
Mohammad Ghannadi Maragheh ◽  
Seyed Pezhman Shirmardi ◽  
Ali Bahrami Samani
Keyword(s):  
Experimental Data ◽  
Bone Metastases ◽  
Absorbed Dose ◽  
Bone Surface ◽  
Mcnp4c Code

scholarly journals Evaluation of the 223Ra-dichloride biodistribution models for the assessment of the doses from internal exposure

2020 ◽  
Vol 2 (1) ◽  
pp. 54-69
Author(s):  
Aleksandr V. Vodovatov ◽  
Larisa A. Chipiga ◽  
Anna E. Petrova ◽  
Andrey A. Stanzhevsky
Keyword(s):  
Prostate Cancer ◽  
Bone Marrow ◽  
Bone Metastases ◽  
Absorbed Dose ◽  
The Body ◽  
Internal Exposure ◽  
Bone Surface ◽  
Red Bone Marrow ◽  
Absorbed Doses ◽  
Healthy Part

Prostate cancer is the most common men urogenital tumor. For most patients with the disseminated neoplastic process in the prostate after the hormonal therapy, the disease gradually progresses in the form of castration-resistant prostate cancer (mCRPC). The use of 223Ra agents is aimed at the treatment of the bone lesions as part of palliative therapy. The physical properties of 223Ra significantly complicate the require direct radiometry for patients with alpha emitters. Hence, the distribution of 223Ra in the body should be evaluated based on the dedicated biodistribution models. The aim of this study was to review and analyze the existing approaches to the evaluation of the biodistribution of 223Ra and its pharmaceutical forms (223Ra-dichloride) for the further assessment of absorbed doses in radiosensitive organs and tissues. The study includes the mathematical models for the estimation of the absorbed doses in various organs and tissues of the body. A review of three different 223Ra biodistribution models is presented: two ICRP models for occupational exposure and a model based on the results of an experimental assessment of 223Ra distribution in patients with mCRPC. It was indicated that the latter model is in good agreement with the results of direct radiometry of patients. A significant drawback of all models is the simulation of the red bone marrow and bone surface as single chambers. During the radionuclide therapy, 223Ra will specifically accumulate in bone metastases, instead of being evenly distributed in the skeleton. Hence, the use of any of the reviewed models will lead both to a significant overestimation of the absorbed dose in a healthy part of the bone surface and red bone marrow, and to an underestimation of the absorbed dose in bone metastases. Currently, this problem has not been solved. That requires the development of new improved models that consider the accumulation of 223Ra in the healthy part of the skeleton and in skeletal metastases.

Effect of ionizing radiation on the kinetics of hydrogenation on the Ni-MgO mixed catalyst

1982 ◽  
Vol 47 (7) ◽  
pp. 1780-1786 ◽  
Author(s):  
Rostislav Kudláček ◽  
Jan Lokoč
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Liquid Phase ◽  
Ionizing Radiation ◽  
Oxide Catalyst ◽  
Absorbed Dose ◽  
Hydrogenation Rate ◽  
Solution Composition ◽  
Mixed Catalyst ◽  
Kinetics Of

The effect of gamma pre-irradiation of the mixed nickel-magnesium oxide catalyst on the kinetics of hydrogenation of maleic acid in the liquid phase has been studied. The changes of the hydrogenation rate are compared with the changes of the adsorbed amount of the acid and with the changes of the solution composition, activation energy, and absorbed dose of the ionizing radiation. From this comparison and from the interpretation of the experimental data it can be deduced that two types of centers can be distinguished on the surface of the catalyst under study, namely the sorption centres for the acid and hydrogen and the reaction centres.

scholarly journals Calculated neutron energy dependence of the dose-response of large recombination chamber

Nukleonika ◽  
2019 ◽  
Vol 64 (4) ◽  
pp. 117-121
Author(s):  
Katarzyna Tymińska ◽  
Michał A. Gryziński ◽  
Maciej Maciak
Keyword(s):  
Experimental Data ◽  
Energy Range ◽  
Total Dose ◽  
Energy Dependence ◽  
Neutron Energy ◽  
Dose Response ◽  
Absorbed Dose ◽  
Wide Energy Range ◽  
Mcnpx Code ◽  
Wide Energy

Abstract A model of REM-2-type chamber was modeled with MCNPX code to study the dose-response to monoenergetic neutrons in wide energy range from thermal to 20 MeV for various compositions of gas in the chamber. The energy dependence of the total dose absorbed in the filling gas was compared with the energy dependence of ambient absorbed dose D*(10) and with experimental data. The results of the studies will be useful for designing new, improved generation of recombination chambers.

A case report of image-based dosimetry of bone metastases with Alpharadin (223Ra-dichloride) therapy: inter-fraction variability of absorbed dose and follow-up

2015 ◽  
Vol 30 (2) ◽  
pp. 163-168 ◽  
Author(s):  
Massimiliano Pacilio ◽  
Guido Ventroni ◽  
Bartolomeo Cassano ◽  
Pasquale Ialongo ◽  
Leda Lorenzon ◽  
...  
Keyword(s):  
Case Report ◽  
Bone Metastases ◽  
Absorbed Dose

Study of inter-fraction variability of absorbed dose to bone metastases and follow-up for a patient who underwent 223Ra-dichloride therapy

2016 ◽  
Vol 32 ◽  
pp. 100-101
Author(s):  
M. Pacilio ◽  
B. Cassano ◽  
G. Ventroni ◽  
P. Ialongo ◽  
L. Lorenzon ◽  
...  
Keyword(s):  
Bone Metastases ◽  
Absorbed Dose

scholarly journals Dosimetry of Bone-Seeking Radiopharmaceuticals for Palliative Therapy of Bone Metastases: A Simulation Study Using GATE Monte Carlo Code

2020 ◽  
Author(s):  
Saman Dalvand ◽  
Hossein Rajabi ◽  
Ameneh Omidi ◽  
Etesam Malekzadeh
Keyword(s):  
Bone Marrow ◽  
Monte Carlo ◽  
Bone Metastases ◽  
Bone Structure ◽  
Palliative Therapy ◽  
Absorbed Dose ◽  
Monte Carlo Code ◽  
Pain Palliation ◽  
Beta Particles ◽  
Absorbed Doses

Purpose: Radiopharmaceutical Therapy (RPT) is one of the effective methods for pain palliation of bone metastases. Bone marrow is a critical organ in bone structure whose absorbed dose should be kept below a certain threshold. The purpose of this study was to calculate and compare absorbed doses of bone-seeking radiopharmaceuticals used in the palliative treatment of bone metastases. Materials and Methods: In this study, the GATE Monte Carlo code was used to simulate a femur bone, which consists of bone marrow, endosteal layer, bone, and soft tissue phantom model. Absorbed doses of the 153Sm-EDTMP, 89SrCl2, 177Lu-EDTMP, 188Re-HEDP, and 223RaCl2 radiopharmaceuticals were calculated in the femur phantom compartments. Results: bone absorbed doses per disintegration from alpha particles of 223RaCl2 is approximately 24 times higher than absorbed doses from beta particles of 89SrCl2. Also, absorbed dose per disintegration from beta particles of 89SrCl2 in the bone is approximately 12, 6 and 1.5 times higher than 177Lu-EDTMP, 153Sm-EDTMP, and 188Re-HEDP, respectively. Moreover, the bone and bone marrow absorbed dose from beta particles of 153Sm-EDTMP is 1.9 times higher than 177Lu-EDTMP. Besides, absorbed dose per disintegration from beta particles of 188Re-HEDP in the bone marrow is approximately 40, 30, 7, and 4 times higher than 223RaCl2, 89SrCl2, 177Lu-EDTMP and 153Sm-EDTMP, respectively. Conclusion: Our results show that 223RaCl2 could be a more efficient radiopharmaceutical for radionuclide therapy of bone metastases. Also, 177Lu-EDTMP, due to low marrow toxicity and comparable bone absorbed dose with 153Sm-EDTMP, can be used for achieving bone pain palliation. Moreover, significantly high bone marrow absorbed dose of 188Re-HEDP should be considered for palliative therapy of metastatic bone patients.

DNA damage modeled with Geant4-DNA: effects of plasmid DNA conformation and experimental conditions

2021 ◽  
Author(s):  
Jorge Naoki Domínguez-Kondo ◽  
Eduardo Barbosa Moreno ◽  
Vaclav Stepan ◽  
Klára Stefanová ◽  
Yann Perrot ◽  
...  
Keyword(s):  
Experimental Data ◽  
Dna Damage ◽  
Standard Deviation ◽  
Brownian Dynamics ◽  
Comprehensive Evaluation ◽  
Reaction Times ◽  
Absorbed Dose ◽  
Strand Break ◽  
Experimental Conditions ◽  
Dna Concentration

Abstract The chemical stage of the Monte Carlo track-structure code Geant4-DNA was extended for its use in DNA strand break (SB) simulations and compared against published experimental data. Geant4-DNA simulations were performed using pUC19 plasmids (2686 base pairs) in a buffered solution of DMSO irradiated by 60Co or 137Cs γ-rays. A comprehensive evaluation of SSB yields was performed considering DMSO, DNA concentration, dose and plasmid supercoiling. The latter was measured using the super helix density value used in a Brownian Dynamics (BD) plasmid generation algorithm. The Geant4-DNA implementation of the Independent Reaction Times method (IRT), developed to simulate the reaction kinetics of radiochemical species, allowed to score the fraction of supercoiled, relaxed and linearized plasmid fractions as a function of the absorbed dose. The percentage of the number of strand breaks after •OH + DNA and H• + DNA reactions, referred as SSB efficiency, obtained using MCTS were 13.77% and 0.74% respectively. This is in reasonable agreement with published values of 12% and 0.8%. The SSB yields as a function of DMSO concentration, DNA concentration and super helix density recreated the expected published experimental behaviors within 5%, one standard deviation. The dose response of SSB and DSB yields agreed with published measurements within 5%, one standard deviation. We demonstrated that the developed extension of IRT in Geant4-DNA, facilitated the reproduction of experimental conditions. Furthermore, its calculations were strongly in agreement with experimental data. These two facts will facilitate the use of this extension in future radiobiological applications, aiding the study of DNA damage mechanisms with a high level of detail.

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