• The Korean Journal of Nuclear Medicine
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• v.36 no.2
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• pp.102-109
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• 2002

Purpose : In gene therapy, tumor cells expressing the herpes simplex virus thymidine kinase are sensitive to prodrugs. Potential prodrugs IVDU and IVFRU were synthesized and radiolabeled with radioiodine for noninvasive imaging of herpes simplex virus type 1 gene expression. Material and Methods : 5-(2-trimethysilyl) vinyl-2'-deoxyuridine and 5-(2-trimethylsilyl)vinyl-2'-fluoro-2'-deoxyuridine, precursors of 5-(2--iodo)viny l-2'-deoxy uridine(IVDU) and 5-(2-iodo)-2'-vinyl-2'-deoxy-2'-fluororibofuranosyl uracil(IVFRU), were synthesized from reaction of trans-1-trimethylsillyl-2-tri-n-butylstannylethylene with 5-iodo-2'-deoxyuridine and 5-iodo-2'-fluoro-2'-deoxyuridine, respectively, on the condition of Pd catalyst. These precursors were separated from reaction mixture by silica gel column chromatography method. Each precursor was radioiodinated with radioiodine by mixing with ICI oxidizing agent. These radioiodinated compounds were purified with HPLC. Radiohalogen exchange has been shown to be effective for the synthesis of products with lower specific activity. Similarly, carrier-added and high specific activity products have been isolated in respectable radiochemical yields using ICI method. Results : Synthetic yield of precursors, IVDU and IVFRU were 43% and 18%, respectively. Radiochemical purity of both compunds was over 98%. Conclusion : We synthesized precursors of IVDU and IVFRU for monitoring of HSV1-tk gene expression. Radiotracers were radioiodinated with high radiolabeling yield by ICI method.

• Journal of Radiation Protection and Research
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• v.42 no.2
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• pp.83-90
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• 2017

Background: Different cases exist in the measurement of thyroid radiobioassays owing to the individual characteristics of the subjects, especially the potential variation in the counting efficiency. An In situ Object Counting System (ISOCS) was developed to perform an efficiency calibration based on the Monte Carlo calculation, as an alternative to conventional calibration methods. The purpose of this study is to evaluate the applicability of ISOCS to thyroid radiobioassays by comparison with a conventional thyroid monitoring system. Materials and Methods: The efficiency calibration of a portable high-purity germanium (HPGe) detector was performed using ISOCS software. In contrast, the conventional efficiency calibration, which needed a radioactive material, was applied to a scintillator-based thyroid monitor. Four radioiodine samples that contained $^{125}I$ and $^{131}I$ in both aqueous solution and gel forms were measured to evaluate radioactivity in the thyroid. ANSI/HPS N13.30 performance criteria, which included the relative bias, relative precision, and root-mean-squared error, were applied to evaluate the performance of the measurement system. Results and Discussion: The portable HPGe detector could measure both radioiodines with ISOCS but the thyroid monitor could not measure $^{125}I$ because of the limited energy resolution of the NaI(Tl) scintillator. The $^{131}I$ results from both detectors agreed to within 5% with the certified results. Moreover, the $^{125}I$ results from the portable HPGe detector agreed to within 10% with the certified results. All measurement results complied with the ANSI/HPS N13.30 performance criteria. Conclusion: The results of the intercomparison program indicated the feasibility of applying ISOCS software to direct thyroid radiobioassays. The portable HPGe detector with ISOCS software can provide the convenience of efficiency calibration and higher energy resolution for identifying photopeaks, compared with a conventional thyroid monitor with a NaI(Tl) scintillator. The application of ISOCS software in a radiation emergency can improve the response in terms of internal contamination monitoring.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.72-79
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• 2017

Arbutin is a hydroquinone derivative with a glucose moiety. As a tyrosinase inhibitor, it is widely used as a skin-whitening cosmetic agent for the treatment of cutaneous hyperpigmentary disorders, such as melasma and freckles. In the medical field, many studies have addressed the use of arbutin in various tumors, but the mechanism for tumor uptake of arbutin is still unclear. In this paper, we radiolabeled arbutin using radioiodine and studied its pharmacokinetics and tumor uptake via biodistribution experiments and single-photon emission computed tomography (SPECT) imaging. Radiolabeled $^{131}I-arbutin$ was stable for up to 24 h in PBS and serum. Biodistribution studies and SPECT imaging indicated high uptake of the compound in the bladder and kidneys shortly after injection. Twenty-four hours post-injection, significant deiodination was observed. Apart from high thyroid uptake, selective tumor uptake was clearly observed. The tumor-to-muscle and tumor-to-blood ratios were 26 and 9, respectively.

• Korean Journal of Head & Neck Oncology
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• v.22 no.1
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• pp.58-61
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• 2006

Differentiated thyroid carcinomas are rarely associated with macroscopic vascular invasion and intraluminal tumor thrombus in great cervical veins. The best treatment for such cases appears to be a total thyroidectomy with en-block resection of the involved vessels, followed by postoperative radioiodine therapy(RI). We report two cases of follicular thyroid carcinoma with vascular invasion and intraluminal tumor thrombosis in great cervical veins that were successfully treated using complete surgical resection and postoperative RI.

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.41-45
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• 2007

A 60 years old female patient presented with $8{\times}6\;cm$ sized painless oval mass in the left parietal region. She had left lobectomy of thyroid gland 10 years ago. Cranial CT, MRI, FGD PET-CT showed a solid mass which invaded left parietal bone. After embolization, craniectomy with tumor excision was performed. Histological examination revealed metastatic follicular cancer originated thyroid gland, with vascular and dura invasion. Postoperatively, neck CT showed right thyroid multiple nodules and right level III multiple lymph node enlargement. Thyroid function test was normal, but level of thyroglobulin was high (72ng/ml). So she had right lobectomy of thyroid gland with lymph node dissection under a diagnosis of follicular carcinoma. But histological examination revealed adenomatous hyperplasia and not lymph node metastasis. After operation, she received radioiodine therapy of 150mCi and then the level of thyroglobulin normalized (8.4ng/ml). The patient is under follow-up since she had operation 4 months ago.

• The Korean Journal of Nuclear Medicine
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• v.8 no.1_2
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• pp.49-55
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• 1974

The authors studied on the 5 cases of solitary thyroid nodule by T3 suppression test and TSH stimulation test. Radioiodine uptake and thyroid scan were observed after administration of dssicated thyroid and TSH. 3 of 5 cases were teated by $^{131}I$ and 2 by long-term adiministration of dessicated thyroid. Following were the results: 1. Nodular tissue was not affected by the administration of dessicated thyroid or TSH. 2. Extranodular tissue responded as normal thyroid tissue on the administration of dessicated thyroid or TSH. 3. There were many gradations from euthyroid to hyperthroid in clinical state. 4. Treatments were succesful in all cases except one case who was treated by long-term administration of dessicated thyroid.

• Nuclear Engineering and Technology
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• v.12 no.2
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• pp.121-126
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• 1980

Selection methods of well labelled insulin fractions based on two different criteria were compared to establish an efficient low level RIA of insulin and to elucidate the correlation between the immunoreactivity and the charcoal-adsorptivity of the radioiodine labelled insulin. The results indicated that the selection of well labelled insulin fractions by means of a charcoal-adsorption test is inappropriate. Generally, the distribution of radioactivity antibody-bindability, and charcoal-adsorptivity of the labelled insulin was not consistent with each other. Thus. the selection should be carried out for every labelling batch to get the utmost assay reliability by antibody-bindability but not by charcoal-adsorptivity. By using the well selected labelled insulin fractions based on antibody-binding, a correct assay for a reference serum was possible, and by extending the incubation time upto 96 hrs, a sharp dose response curve could be obtained even in the range of below 5 $\mu$U/ml standard insulin doses.

• The Korean Journal of Nuclear Medicine
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• v.14 no.2
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• pp.35-40
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• 1980

In order to compare the therapeutic effect as well as side effects between antithyroid therapy and radioiodine therapy in hyperthyroidism, the author evaluated 111 cases of hyperthyroidism which were composed of 57 patients with antithyroid treatment, 23 patients with combined treatment comprising of antithyroid and radioactive iodine ($^{131}I$) and 31 patients with treatment of $^{131}I$ alone. The $^{131}I$ treatment was limited to older age, above 20 years of age, and not employed in patients with pregnancy and lactation. The patients treated with antithyroid belonged to relatively younger age, and also milder in symptoms and thyroid function tests. The remission rate of antithyroid therapy group was 97.8% within 16 months. Among them the early remission rate occured within 4 months was found to be 21.7%. The combined therapy group, having prescribed more severe cases, showed the remission rate to be 75% within 16 months. The remission rate of $^{131}I$ therapy group revealed 90.9% within 16 months. Among them the early remission rate taking place within 4 months disclosed 16.7%. The side effects of antithyroid drug, propylthiouracil, were noted as follows: itching (2.7%) skin rashes (1.3%), and adverse enlargement of goiter (10.7%). The side effects $^{131}I$ therapy were transient hypothyroidism(3.9%) permanent hypothyroidism (7.8%) and itching (2.0%).

• Journal of Radiation Protection and Research
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• v.44 no.4
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• pp.161-165
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• 2019

Background: Not only regulatory framework including radiation protection quantities and regulatory standards, but also methodology for regulatory compliance may be different in each country due to inherent philosophy for radiation protection. Materials and Methods: Based on the Korean regulatory models, off-site radiological dose resulting from the routine releases of gaseous radioactive effluents was calculated by applying the parameter values and assumptions recommended in the Korean and Japanese regulations. Results and Discussion: Effective dose for adult based on the Korean recommendation were 17.5 and 1.6 times higher than those of Japanese recommendation for ¹³¹I and ¹³³I, respectively, for the same atmosphere dispersion and ground deposition factors. Conclusion: It was due to different parameter values and assumptions recommended for the purpose of evaluating compliance with dose criteria for the radiation protection of the public in each country.

• The Korean Journal of Nuclear Medicine
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• v.3 no.2
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• pp.29-31
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• 1969

The author observed the uptake rate of $^{131}I$ by the thyroid gland, and disappearing rate of the $^{131}I$ at the site of the intradermal injection of 0.1ml of 5mCi of $^{131}I$ in normal physiologic saline on 20 patients with hyperthyroidism and on 15 patients with hypothyroidism who visited the Radioisotpe department of the Pusan National University Hospital during the period from January 1967 to Aug. 1968, and during the same period 15 normal persons were examined by the same methods and found. The results were as follows: (1) The disappearance rate of $^{131}I$ at the injected site was highest in the cases of hyperthyrodism. The next highest results were obtained in the normal cases. The lowest results were obtained in the cases of hypothyroidism. (2) The uptake rate of the thyroid gland after intradermal injection of the $^{131}I$ was highest in the cases of hyperthyroidism and the next highest results were obtained in the cases of nomal findings. The lowest results were obtained in the cases of hypothyroidism. (3) In conclusion, the intradermal method of injecting $^{131}I$ by the author is a useful way of testing the function of the thyroid gland.