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Technetium-99m : from nuclear medicine applications to fi ne sediment transport studies

Bandeira J. V., Salim L. H.

Nukleonika

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2017

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Vol. 62, No. 4

295--302

EN

The present work is a contribution to rescue the history of development of the application of 99mTc, widely used in nuclear medicine, to its use as tracer for the study of the transport of fi ne sediment in suspension, in water environment. It addresses the usefulness of its application in obtaining important parameters in environmental studies, illustrating them with some applications already performed and the results obtained. This kind of study, when associated with information on hydrodynamic parameters, for example, river, tidal, wind and wave currents, are powerful tools for the understanding and quantification of fi ne sediment transport in suspension. Fine sediment is an important vector in the transportation of heavy metals, organic matter and nutrients in water environment, and the quantitative knowledge of its behaviour is mandatory for studies of environmental impacts. Fine sediment labelled with 99mTc, can also be used to study the effect of human interventions, such as dredging of reservoirs, access channels and harbours, and the dumping of dredged materials in water bodies. Besides that, it can be used to optimize dredging works, evaluating the technical and economic feasibility of dumping sites and their environmental impact. It is a valuable support in the calibration and validation of mathematical models for sediment dynamics.

2

Preparation and biodistribution of 99mTc-IgG-HYNIC in normal rats

Rajabifar S., Akhlaghi M., Jalilian A. R., Bolourinovin F., Maashkar B., Talebimehrdar M., Ghafouri M.

Nukleonika

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2009

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Vol. 54, No. 4

279-284

EN

Human gamma globulin can be labeled by a direct or indirect method of radiotracer incorporated in a protein molecule. In this indirect method hydrazinonicotinic acid (HYNIC) is used which saves the structure and biological activity of the protein. Our goal was the efficient labeling of the human gamma globulin and evaluation of its biodistribution in different organs which can be used on experimentally induced infection causing inflammation. Immune globulin is mixed with s-hynic and IgG-hynic is developed using sidle A-lyzer and stored at –20°C which can be used at least for six months and then Sn-tricine kit is prepared which is used for 99mTc labeling. Efficiency of 99mTc-IgG-hynic labeling at pH 6.4 was very much dependent on ligand (hynic) and coligand (tricine) presence in the reaction mixture. Radiochemical purity was more than 90% in the kits prepared. Serum stability study showed no decomposition of 99mTc from the complex. The biodistribution studies showed the highest percentage ID/organ in the blood, liver and kidney, respectively. A human gamma globulin was successfully labeled through hynic to 99mTc by an indirect method with high radiochemical purity.

3

E.Cam DUET gamma camera model validation in GATE

Borys D., Szczucka K., Gorczewski K., Bekman B.

Journal of Medical Informatics & Technologies

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2007

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Vol. 11

245--252

EN

Monte Carlo simulations are more and more popular trend in nuclear medicine imaging. They were also widely used in radiotherapy and brachytherapy with use of more general simulation software. GATE (Geant4 Application for Tomographic Emission) is a platform developed on general Monte Carlo code designed for simulating and tracking the passage of particles through matter (Geant4) but is specifically designed for nuclear medicine imaging purposes. The aim of this work was to create and validate a model of specific gamma-camera (E.Cam DUET), used in our department, for further use in image analysis and dosimetry field, with GATE simulation platform. We have modeled in first step a point source in the air in three configurations of gamma camera (without collimator, with low-energy high-resolution (LEHR) collimator and with high-energy (HE collimator)), then we have created a phantom with three spherical sources of different sizes but with the same concentration of the radiopharmaceutical. Simulation results were compared to the measured values of the energy spectrum and images obtained on the detectors, and show a good agreement for the point source experiments and revealed some differences for the phantom studies. This results shows that some additional tests and refinements are required but also allows us to study the image degrading quality factors, such as septal penetration and to work towards eliminating them from the pictures.