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    Effect of a plant origin drug on the biodistribution of Tc-99m-DTPA in Wistar albino rats
    (Soc Brasileira Farmacognosia, 2012) Zora, Hasan; Muftuler, Zumrut F. Biber; Demir, Ilknur; Kilcar, Ayfer Yurt; Ichedef, Cigdem; Unak, Perihan
    In recent years all over the world, medicinal plants are used quite a lot but side effects of biological and chemical contents and radiopharmaceutical interactions for each consumer in question aren't entirely well-known. The studies of plant origin drug interaction with radiopharmaceuticals are highly relevant and desired. One of them is passiflora syrup (Passiflora incarnata L., Passifloraceae) which is widely used for depression, insomnia, anxiety and menopause period. The aim of current study is to evaluate possible effects of passiflora syrup on the biodistribution of Tc-99m-DTPA and its blood cells uptake. DTPA was labeled with Tc-99m radionuclide. Biodistribution studies were performed on male Wistar albino rats which were treated via oral feeding-gavage-method with either passiflora syrup or 0.9 % NaCl as control group for ten days. Blood samples were obtained by cardiac blood withdrawal from the rats and they were radiolabeled. The biodistribution results showed that the passiflora syrup decreased the uptake of Tc-99m-DTPA in kidneys and in blood cells. Tc-99m-DTPA being used widely as a kidney diagnostic agent in nuclear medicine seems to be interacting with orally taken passiflora. Passiflora syrup may modify the uptake of Tc-99m-DTPA by kidney. The knowledge of this negative effect may contribute to reduce the risk of misdiagnosis and/or repetition of the examinations in nuclear medicine.
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    In Vivo Investigation of Radiolabeled Bevacizumab in Healthy Rat Tissues
    (Inst Tecnologia Parana, 2011) Demir, Ilknur; Muftuler, Fazilet Zumrut Biber; Unak, Perihan; Acar, Cigdem
    In this study, BevMab was conjugated with the bifunctional chelating agent [diethylenetriamine pentaacetic acid (DTPA)] and the product (BevMab-DTPA) was labeled with 99mTc using stannous chloride reducing method. The quality control studies of radiolabeled compound (99mTc-BevMab-DTPA) were done with Thin Layer Radio Chromatography (TLRC) and High Performance Liquid Radio Chromatography (HPLRC) methods (% 95 =) to confirm the labeling efficiency. High radiochemical yield [98.07 % +/- 2.17 (n = 13)] was obtained by TLRC method. Biodistribution studies of 99mTc labeled BevMab-DTPA was run on healthy female and male Albino Wistar rats. The distribution figures demonstrated that the radiolabeled compound was eliminated through the kidneys and accumulated in urinary bladder. The values of the BevMab-DTPA uptakes were similar in heart, blood, liver and spleen in both sexes.
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    Radiolabeling of EGCG with I-131 and biodistribution in rats
    (Birkhauser Boston Inc, 2012) Toksoz, Feriha; Demir, Ilknur; Bayrak, Elif; Kocagozoglu, Gamze; Onursal, Mehmet; Karademir, Gulgun; Lambrecht, Fatma Yurt
    Epigallocatechin gallate (EGCG), is the most abundant and widely studied catechin in green tea (Camellia sinensis Theaceae). The inhibitory effects of EGCG and green tea extract on carcinogenesis in various organs in rodents have now been demonstrated over the past decade. The aim of study was to label EGCG with I-131, to determinate its structure and to evaluate its biodistribution in Wistar rats. Radiolabeling was carried out by direct electrophilic iodination method (iodogen) and yield was determined by radio thin layer chromatography (RTLC). Radiolabelling yield is determined as 89 +/- A 1.0%. Besides, determination of structure of iodinated molecule, serum stability, and partition coefficient experiments was performed. The structure analysis of synthesized cold I-127-EGCG complex was assessed with LC-MS-MS and H-1-NMR. H-1-NMR and LC-MS-MS results of iodinated EGCG (I-127-EGCG) show that oxidize iodine reacts electrophilic with aromatic ring. Serum stability results showed that in vitro stability of I-131-EGCG was quite high. It is observed that labeling percentage decreased 83 +/- A 2% at 24th, Partition coefficient results show that the partition coefficient of EGCG was calculated as theoretical partition coefficient = 2.04 +/- A 0.42 and the experimental partition coefficient of I-131-EGCG was found as 1.46 +/- A 0.2. The biodistribution data shown that the maximum uptake of the radioiodinated EGCG was seen in lung and pancreas at 30 min. The blocking assay results indicated that the uptake of I-131-EGCG in lung was not significantly change (0.25, 0.23, and 0.22%ID/g at 30, 60, and 150 min, respectively). Biodistribution data showed no significant uptake in a specific organ of the rat. Hence radiolabeled EGCG is seen in some organs (lung, liver, pancreas, kidney, etc.).
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    Synthesis of a radioiodinated antiestrogen glucuronide compound (TAM-G)
    (Springer, 2011) Muftuler, Fazilet Zumrut Biber; Unak, Perihan; Ichedef, Cigdem; Demir, Ilknur
    Tamoxifen [TAM; ([Z]-2-[4-(1,2-diphenyl-1-di-butenyl)-phenoxy]-N,N-dimethylethanamine) has been used as an antiestrogen drug for treatment and prevention of human breast cancer. The aim of this study is conjugation of hydrophilic glucuronic acid to the starting substance TAM and labeling with I-131 using iodogen as oxidizing agent. The reactions are completed in three steps, including enzymatic reaction, with the following sub-steps; preparation of microsomal fraction from rat liver and subsequent purification of UDP-glucuronyl transferase (UDPGT), estimation of protein amount in microsomal samples and glucuronidation reaction. Synthesized glucuronide derivative (TAM-G) was purified using high performance liquid chromatography (HPLC). Mass spectroscopy of cold standard showed that the labeling most probably occurs in ortho position to the aromatic ring containing the ether group of TAM-G as expected. Radiochemical yield of the I-131 labeled TAM-G ([I-131]TAM-G) is determined by using Thin Layer Radio Chromatography (TLRC). The radiopharmaceutical potential of [I-131]TAM-G is examined by biodistribution studies that is run on normal female Albino Wistar rats. According to biodistribution results I-131 labeled TAM-G may be proposed as a new antiestrogen glucuronide imaging agent for breast and uterus.