No abstract

No abstract

Complexes [Au(2Ac4oT)Cl][AuCl2] (1), [Au(Hpy2Ac4mT)Cl2]Cl·H2O (2), [Au(Hpy2Ac4pT)Cl2]Cl (3), [Pt(H2Ac4oT)Cl]Cl (4), [Pt(2Ac4mT)Cl]·H2O (5), [Pt(2Ac4pT)Cl] (6) and [Pt(L)Cl2OH], L = 2Ac4mT (7), 2Ac4oT (8), 2Ac4pT (9) were prepared with N(4)-ortho- (H2Ac4oT), N(4)-meta- (H2Ac4mT) and N(4)-para- (H2Ac4pT) tolyl-2-acetylpyridine thiosemicarbazone. The cytotoxic activities of all compounds were assayed against U-87 and T-98 human malignant glioma cell lines. Upon coordination cytotoxicity improved in 2, 5 and 8. In general, the gold(III) complexes were more cytotoxic than those with platinum(II,IV). Several of these compounds proved to be more active than cisplatin and auranofin used as controls. The gold(III) complexes probably act by inhibiting the activity of thioredoxin reductase enzyme whereas the mode of action of the platinum(II,IV) complexes involves binding to DNA. Cells treated with the studied compounds presented morphological changes such as cell shrinkage and blebs formation, which indicate cell death by apoptosis induction.

18F-Fluoroestradiol ([18F]FES), an estrogen analog, is a radiopharmaceutical used in Positron Emission Tomography (PET) that allows evaluating the tumor cell receptor profile and the best therapy strategy, the staging, the prognosis and the response to therapy in several breast cancer cases. As there is not any pharmacopoeia’s monograph of [18F]FES to standardize its quality control criteria, this work presents a new HPLC’s method to perform the [18F]FES radiochemical purity. A liquid chromatograph was used with radioactivity and ultraviolet detectors. Three concentrations of fluoroestradiol standard solution were used along the test. Their retention time was compared to its relative radiolabelled analogue to confirm its identity. Several mobile phases with acetonitrile and two mobile phase flows were tested to optimize the runs. Peaks symmetry, retention time, theoretical plates and resolution were analyzed to choose the best conditions. The mean retention time of both standard Fluoroestradiol and [18F]FES solutions were the same, demonstrating that [18F]FES formulation did not interfere with [18F]FES analysis. The best conditions were 1.2 mL/min and isocratic 40% V/V acetonitrile in water, which gave [18F]FES peak resolution greater than 6 and symmetry factor of 1. Thus, the developed method is ready to be validated and implemented in [18F]FES quality control routine in CDTN/Brazil.

Activimeters (or dose calibrators) are essential instruments to verify activity of radiopharmaceutical after production and also before the dose administration in humans or animals for molecular imaging. The efficiency and safety measurements depend on, beside other factors, constancy tests and quality assurance. Thereby, the aim of this work was to perform constancy tests and quality assurance in the activimeters of the UPPR/CDTN, based on the CNEN-NN 3.05 Brazilian standard and the manufacturer's manual. Physical inspection, auto zero, background check, camera voltage, data check and constancy test were done. In addition, accuracy and precision tests were performed using a set of standard certified radioactive sources (57Co, 133Ba and 137Cs), according to the CNEN NN 3.05 Brazilian standard. Linearity test was also performed to evaluate the response of the equipment in over the entire range of activities used in routine. The equipments are periodically submitted to the quality control tests and the results were compared. After performing the proposed tests it is possible to conclude that activimeters are in accordance with the requirements of the CNEN standard and manufacturer´s manual. A quality control checklist was prepared to guide users and to record the results of quality assurance testing to monitor the equipment performance. This initiative is part of the quality assurance program implemented at UPPR.