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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Dosimetry,Gallium-67,Radiation Dose
- چکیده:
- چکیده انگلیسی: Introduction
Gallium-67 (67Ga) has been used as a radionuclide for imaging a variety of solid tumors since 1969. Since then use of various gallium-based radiotracers has been reported. Recently, 67Ga-labeled acetylacetate bis(thiosemicarbazones) (67Ga-AATS) complex with significant tumor accumulation and fast blood clearance has been employed.
Materials and Methods
In this study, the absorbed dose of 67Ga-AATS in each human organ was evaluated and compared with 67Ga-citrate as the most commonly used form of 67Ga in nuclear medicine. 67Ga was produced via 68Zn(p,2n)67Ga reaction at 30 MeV cyclotron. Moreover, 67Ga-AATS was produced by adding 50 µl of AATS to absolute ethanol (1 mg/ml) in a gallium-containing vial at 80-90 °C. The absorbed dose of each human organ was calculated, using RADAR method, based on biodistribution data in Wistar rats.
Results
According to the results, 67Ga-AATS was produced with radionuclidic and radiochemical purity higher than 99% and 93%, respectively. The highest absorbed dose was reported in the bone surface (0.401 mGy/MBq), whereas the whole-body absorbed dose was 0.092 mGy/MBq.
Conclusion
The absorbed dose of each human organ was comparable with the absorbed dose received by each organ after 67Ga-citrate injection. Considering this interesting finding and the significant tumor uptake, it seems that 67Ga-AATS can be used as an appropriate SPECT tracer.- انتشار مقاله: 07-07-1393
- نویسندگان: Hassan Yousefnia,Samaneh Zolghadri,Amir Reza Jalilian
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Inhibition,thermodynamic changes,dithiocarbamate sodium salts,mushroom tyrosinase
- چکیده:
- چکیده انگلیسی: A mono- and a bi-functional dithiocarbamates as sodium salts were obtained by treating p-peridine or p-perazine in aceton-water mixture with CS2 in the presence of NaOH. These anionic water soluble compounds have been characterized by elemental analysis, IR and 1H NMR spectroscopic studies. Both compounds (p-peridine (I) and p-perazine-bis dithiocarbamate (II) sodium salts) were examined for inhibition of mushroom tyrosinase (MT) activity. The results showed that they inhibit MT competitively. KI values of two compounds at 27°C are 2 and 4 mM. Therefore, the compound (I) is more potent than (II). They chelate active site of tyrosinase via electrostatic interactions. These conclusions are proved by obtained thermodynamic parameters and fluorescence studies. Extrinsic fluorescence studies disprove any tertiary structure changes of MT. Major enthalpy changes in binding of compound (II) in comparison to (I) show that including two carbamate tails in such compounds disturb balancing of hydrophobic interactions with vicinity of active site of enzyme.
- انتشار مقاله: 13-09-1396
- نویسندگان: Ehsan Amin,Ali Akbar Saboury,Hassan Mansouri-Torshizi,Samaneh Zolghadri
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Oceania Journal of Nuclear Medicine and Biology
- نوع مقاله: Journal Article
- کلمات کلیدی: Ga-68,Octreotide,Internal Dosimetry,Somatostatin
- چکیده:
- چکیده انگلیسی:
Objective(s): Gallium-68 DOTA-DPhe1-Tyr3-Octreotide (68Ga-DOTATOC) has been applied by several European centers for the treatment of a variety of human malignancies. Nevertheless, definitive dosimetric data are yet unavailable. According to the Society of Nuclear Medicine and Molecular Imaging, researchers are investigating the safety and efficacy of this radiotracer to meet Food and Drug Administration requirements. The aim of this study was to introduce the optimized procedure for 68Ga-DOTATOC preparation, using a novel germanium-68 (68Ge)/68Ga generator in Iran and evaluate the absorbed doses in numerous organs with high accuracy.
Methods: The optimized conditions for preparing the radiolabeled complex were determined via several experiments by changing the ligand concentration, pH, temperature and incubation time. Radiochemical purity of the complex was assessed, using high-performance liquid chromatography and instant thin-layer chromatography. The absorbed dose of human organs was evaluated, based on biodistribution studies on Syrian rats via Radiation Absorbed Dose Assessment Resource Method.
Results: 68Ga-DOTATOC was prepared with radiochemical purity of >98% and specific activity of 39.6 MBq/nmol. The complex demonstrated great stability at room temperature and in human serum at 37°C at least two hours after preparation. Significant uptake was observed in somatostatin receptor-positive tissues such as pancreatic and adrenal tissues (12.83 %ID/g and 0.91 %ID/g, respectively). Dose estimations in human organs showed that the pancreas, kidneys and adrenal glands received the maximum absorbed doses (0.105, 0.074 and 0.010 mGy/MBq, respectively). Also, the effective absorbed dose was estimated at 0.026 mSv/MBq for 68Ga-DOTATOC.
Conclusion: The obtained results showed that 68Ga-DOTATOC can be considered as an effective agent for clinical PET imaging in Iran.- انتشار مقاله: 15-02-1394
- نویسندگان: Mojdeh Naderi,Samaneh Zolghadri,Hassan Yousefnia,Ali Ramazani,Amir Reza Jalilian
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Oceania Journal of Nuclear Medicine and Biology
- نوع مقاله: Journal Article
- کلمات کلیدی: Bone pain palliation,Lu-177,TTHMP,Dosimetry
- چکیده:
- چکیده انگلیسی: Objective(s): Recently, bone-avid radiopharmaceuticals have been shown to have potential benefits for the treatment of widespread bone metastases. Although 177Lutriethylene tetramine hexa methylene phosphonic acid (abbreviated as 177Lu- TTHMP), as an agent for bone pain palliation, has been evaluated in previous studies, there are large discrepancies between the obtained results. In this study, production, quality control, biodistribution, and dose evaluation of 177Lu-TTHMP have been investigated and compared with the previously reported data.
Methods: TTHMP was synthesized and characterized, using spectroscopic methods. Radiochemical purity of the 177Lu-TTHMP complex was determined using instant thin-layer chromatography (ITLC) and high performance liquid chromatography (HPLC) methods. The complex was injected to wild-type rats and biodistribution was studied for 7 days. Preliminary dose evaluation was investigated based on
biodistribution data in rats.
Results: 177Lu was prepared with 2.6-3 GBq/mg specific activity and radionuclide purity of 99.98%. 177Lu-TTHMP was successfully prepared with high radiochemical purity (>99%). The complex showed rapid bone uptake, while accumulation in other organs was insignificant. Dosimetric results showed that all tissues received almost insignificant absorbed doses in comparison with bone tissues.
Conclusion: Based on the obtained results, this radiopharmaceutical can be a good candidate for bone pain palliation therapy in skeletal metastases.- انتشار مقاله: 23-01-1393
- نویسندگان: Samaneh Zolghadri,Hassan Yousefnia,Amir Reza Jalilian,Mohammad Ghannadi-maragheh
- مشاهده