Marija Jeremic

Unexpected effect of furosemide on radioiodine urinary excretion in patients with differentiated thyroid carcinomas treated with iodine 131.

BACKGROUND In patients receiving (131)I for therapeutic purposes, diuretics are frequently used in an attempt to accelerate elimination of unbound radioiodine, reduce its adverse effects, and shorten the hospital stay. The aims of our study were to investigate the influence of furosemide therapy on urinary excretion of (131)I in patients with differentiated thyroid cancer (DTC), referred to radioiodine ablation after thyroidectomy, and to investigate whether diuretics are useful in daily practice in patients with DTC. METHODS Forty-three patients with DTC who had normal renal function and low (131)I uptake in cervical region (3.55 +/- 3.45%) were included in this study. The furosemide (20 mg) and potassium chloride (250 mg) were given orally to 23 patients 3 hours after the (131)I administration, and then q8h for 3 days. Twenty patients did not receive either furosemide or potassium chloride. After (131)I administration, the patients collected their urine for 3 days, and radioactivity of urine sample from each micturition was expressed as percentage of the administered dose. Radioactivity of blood samples was measured after 72 hours, and the values were corrected for decay of (131)I and expressed in relation to the administered dose. Initial whole-body measurement (immediately after (131)I administration) and the whole-body measurement after 72 hours were recorded for all patients. The 72-hour whole-body measurement was corrected for decay of (131)I, and expressed as a percentage of the initial whole-body measurement. RESULTS Urinary excretion of (131)I was significantly lower in the patients who were taking furosemide and potassium chloride compared with the control group. The whole-body measurements after 72 hours (13.22 +/- 6.55% vs. 8.24 +/- 3.39% of the initial; p < 0.01, respectively) and the blood radioactivity (34.66 +/- 24.84 vs. 11.64 +/- 8.32 cpm/mL per 1 MBq of administered (131)I, p < 0.01) were found to be unexpectedly higher in the patients who were taking furosemide and potassium chloride compared with the control group. CONCLUSION Our results demonstrated that furosemide given as an adjuvant medication in patients with DTC causes a significant decrease in urinary excretion of radioiodine and its higher blood concentration. Therefore, furosemide should not be recommended as an adjuvant therapy to radioiodine ablation in patients with DTC previously iodine depleted by low-iodine diet.

Preparation, configurational and DFT-NBO analysis of nickel(II) complexes with edta-type ligands containing six-membered backbone ring: crystal structure of [Ni(H2O)(6)][Ni(1,3-pdta)]center dot 2H(2)O

New hexadentate nickel(II) complex Mg[Ni(1,3-pd3ap)]·10H2O containing unsymmetrical edta-type ligand, 1,3-propanediamine-N,N,N′-triacetate-N′-3-propionate (1,3-pd3ap), has been prepared, chromatographically separated, and characterized. Only one [trans(O5)] of the two possible geometrical isomers was isolated. In this isomer, the two five-membered glycinate rings (R rings) occupy trans-axial sites while the one glycinate ring and one β-alaninate ring lie in the equatorial plane with the two diamine nitrogens (G rings). This result confirms the assignment made on the basis of the density functional theory (DFT), IR, and UV–Vis spectral data analysis. In order to see cation influence on the structural and electronic behavior, [Ni(H2O)6][Ni(1,3-pdta)]·2H2O complex has also been prepared and its structure verified by an X-ray analysis. Spectral data and electronic transition assignment, DFT–natural bonding orbital, and an extensive strain analysis are discussed in comparison with those of other [Ni(edta-type)]2− complexes of known configuration.

Synthesis, structural analysis, solution equilibria and biological activity of rhodium(III) complexes with a quinquedentate polyaminopolycarboxylate

Two rhodium(III) complexes [Rh(ed3a)(OH2)]·H2O (1) and Na[Rh(ed3a)Cl]·H2O (2) with ethylenediamine-N,N,N′-triacetate (ed3a) have been synthesized and characterized by elemental, spectroscopic and structural analyses. The crystal structure of (1) and (2) and the spectroscopic analysis of the two rhodium(III)–ed3a complexes are discussed in detail. The protonation constants of H3ed3a and the conditional stability constants of its RhIII complexes have been determined in aqueous solution by pH potentiometry and UV-Vis spectrophotometry. Molecular mechanics (MM) and density functional theory (DFT) have been used to model all possible geometric isomers, determine the global energy minimum and compare the computed with the experimentally observed structures. The cytotoxic activity of the new RhIII complexes was evaluated by an MTT assay against four human cancer lines (MCF-7, A549, HT-29 and HeLa) and a normal human cell line (MRC-5). A549, HT-29 and HeLa cells were sensitive to all compounds tested, while the breast carcinoma cell line MCF-7 was only sensitive to the reference compounds (doxorubicin and cisplatin). Western blot (WB) analysis of the effects of the tested compounds indicates that both complexes increase the expression of caspase 3 and consequently the involvement of this enzyme in apoptotic processes of the treated cells. WB also demonstrates proteolytic cleavage of poly-(ADP-ribose)polymerase (PARP) in HeLa cells after treatment with both tested substances. Flow cytometry confirmed apoptotic cell death and showed the induction of cell cycle termination as a possible promoter of apoptosis.

Hybrid Vision-Fusion system for whole-body scintigraphy

Radioiodine therapy in the treatment of differentiated thyroid carcinoma (DTC) is used in clinical practice for the ablation of thyroid residues and/or destruction of tumour tissue. Whole-body scintigraphy for visualization of the spatial 131I distribution performed by a gamma camera (GC) is a standard procedure in DTC patients after application of radioiodine therapy. A common problem is the precise topographic localization of regions where radioiodine is accumulated even in SPECT imaging. SPECT/CT can provide precise topographic localization of regions where radioiodine is accumulated, but it is often unavailable, especially in developing countries because of the high price of the equipment. In this paper, we present a Vision-Fusion system as an affordable solution for 1) acquiring an optical whole-body image during routine whole-body scintigraphy and 2) fusing gamma and optical images (also available for the auto-contour mode of GC). The estimated prediction error for image registration is 1.84 mm. The validity of fusing was tested by performing simultaneous optical and scintigraphy image acquisition of the bar phantom. The fusion result shows that the fusing process has a slight influence and is lower than the spatial resolution of GC (mean value ± standard deviation: 1.24 ± 0.22 mm). The Vision-Fusion system was used for radioiodine post-therapeutic treatment, and 17 patients were followed (11 women and 6 men, with an average age of 48.18 ± 13.27 years). Visual inspection showed no misregistration. Based on our first clinical experience, we noticed that the Vision-Fusion system could be very useful for improving the diagnostic possibility of whole-body scintigraphy after radioiodine therapy. Additionally, the proposed Vision-Fusion software can be used as an upgrade for any GC to improve localizations of thyroid/tumour tissue.

Hybrid SPECT/MSCT 3D computational preoperative simulation in breast cancer surgery

Hybrid imaging combining CT and SPECT is becoming a state of the art nuclear medicine technique. Advantages of hybrid imaging are improved quality of the images using CT data for attenuation correction based on true transmission density data in an individual patient, and CT and SPECT fusion images providing accurate localization of the tracer uptake. Accurate localization of increased tracer uptake is very important especially in the diagnostic of tumors. For this purpose a software developed for generating 3D models from standard DICOM images, obtained from CT and SPECT, and then merging these 3D objects, provides us with the exact location of sentinels nodes. This is certainly very helpful for a surgeon performing biopsy. The ability of SPECT/CT to improve diagnostic accuracy, especially specificity, has a great potential in further development of nuclear medicine techniques in evaluation of tumors.