• Title/Summary/Keyword: Thallium

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Bonding of Electron Deficient Thallium-Metal Cluster Compound

  • Kang, Sung-Kwon
    • Bulletin of the Korean Chemical Society
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    • v.14 no.2
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    • pp.191-195
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    • 1993
  • Molecular orbital calculations at the extended Huckel level have been carried out for an electron deficient cluster, $Tl_3(FeL_3)_2{(FeL_4)_3}^{-3}$, where L=CO or $H^-$. The LUMO, $2a_2$", is destabilized by the secondary interaction of the LUMO with $1a_2$" on $(FeL_3)_2$ fragment. This is one of six skeletal bonding orbitals which are associated with $Tl-FeL_3$ bonds. Overlap population analysis has been applied to account for two kinds of Tl-Fe bonds. Replacement of the terminal $C_{3v}$, $FeL_4$, by the $C_{2v}$, $FeL_4$ units in cluster results in slight energy stabilization of the cluster.

The Study on the drug pharmacokinetics according to the progression of liver disease

  • Sohn, Soo-Jung;Choi, Hong-Serck;Ahn, Mee-Ryung;Chung, Hye-Joo;Yoo, Tae-Moo;Lee, Min-Ho;Park, Moon-Seung;Shin, In-Chul;Kim, Ju-ll
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.308.1-308.1
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    • 2003
  • We underwent this study to know correlation between the amount of portosysternic shunt/hepatic fibrosis and bioavailability parameters such as AUC, Cmax, Tmax and t1 /2 of high extraction ratio drug, propranolol, in CCl4-induced liver cirrhosis model of rats. This study describes the bioavaility study of propranolol(5 mg/kg), Shunt Index using thallium-201 per rectum scintigraphy to to measure the amount of portosystemic shunt indirectly and intrahepatic hydroxyproline content performed in the CCl4-induced liver cirrhosis model of rats. (omitted)

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Prediction of Salvaged Myocardium in Patients with Acute Myocardial Infarction after Primary Percutaneous Coronary Angioplasty using early Thallium-201 Redistribution Myocardial Perfusion Imaging (급성심근경색증의 일차적 관동맥성형술 후 조기 Tl-201 재분포영상을 이용한 구조심근 예측)

  • Choi, Joon-Young;Yang, You-Jung;Choi, Seung-Jin;Yeo, Jeong-Seok;Park, Seong-Wook;Song, Jae-Kwan;Moon, Dae-Hyuk
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.4
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    • pp.219-228
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    • 2003
  • Purpose: The amount of salvaged myocardium is an important prognostic factor in patients with acute myocardial infarction (MI). We investigated if early Tl-201 SPECT imaging could be used to predict the salvaged myocardium and functional recovery in acute MI after primary PTCA. Materials and Methods: In 36 patients with first acute MI treated with primary PTCA, serial echocardiography and Tl-201 SPECT imaging ($5.8{\pm}2.1$ days after PTDA) were performed. Regional wall motion and perfusion were quantified with on 16-segment myocardial model with 5-point and 4-point scaling system, respectively. Results: Wall motion was improved in 78 of the 212 dyssynergic segments on 1 month follow-up echocardiography and 97 on 7 months follow-up echocardiography, which were proved to be salvaged myocardium. The areas under receiver operating characteristic curves of Tl-201 perfusion score for detecting salvaged myocardial segments were 0.79 for 1 month follow-up and 0.83 for 7 months follow-up. The sensitivity and specificity of Tl-201 redistribution images with optimum cutoff of 40% of peak thallium activity for detecting salvaged myocardium were 84.6% and 55.2% for 1 month follow-up, and 87.6% and 64.3% for 7 months follow-up, respectively. There was a linear relationship between the percentage of peak thallium activity on early redistribution imaging and the likelihood of segmental functional improvement 7 months after reperfusion. Conclusion: Tl-201 myocardial perfusion SPECT imaging performed early within 10 days after reperfusion can be used to predict the salvaged myocardium and functional recovery with high sensitivity during the 7 months following primary PTCA in patients with acute MI.

Quantitative Measurement of Membrane $Na^+-K^+$ ATPase Activity using Thallium-201 : Comparison with Rubidium-86 (Thallium-201을 이용한 세포막 $Na^+-K^+$ ATPase 활성도 측정: Rubidium-86 측정법과의 비교)

  • Lee, Jae-Tae;Lee, In-Kyu;Sohn, Sang-Kyun;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.2
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    • pp.121-128
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    • 1998
  • Purpose: $Na^+-K^+$ ATPase activity has been estimated by the degree of inhibition of cation transport by cardiac glycosides (ouabain) using Rb-86 as a substrate. The biological characteristisc of T1-201 is known to be similar to those of potassium as a transport substrate in the presence of glucose, insulin or phobol myristate acetate (PMA). The purpose of this study was to measure ouabain sensitive $Na^+-K^+$ ATPase activity using T1-201 and compare with that using Rb-86. Materials and Methods: Smooth muscle cells isolated from rat aorta or human placental umbilical artery were cultured, and used to measure cellular $Na^+-K^+$ ATPase activity. $Na^+-K^+$ ATPase activity was measured as a percentage decrease in cellular uptake of T1-201 or Rb-86 by ouabain under the presence of glucose, insulin or PMA in media. Results: $Na^+-K^+$ ATPase activity measured with T1-201, as a transport substrate, was not different from those measured with Rb-86 in rat or human smooth muscle cell preparation. Incubation with high concentration glucose resulted in about 30% decrease in enzyme activity. In contrast, insulin or PMA resulted in 10-70% or 28% increases from baseline activity, respectively. Conclusion: These results suggests that 71-201 could replace Rb-86 in measurement of ouabain sensitive $Na^+-K^+$ ATPase activity in vitro. High level of glucose concentration decreased cellular $Na^+-K^+$ ATPase activity, but insulin or PMA increased it.

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Effects of Pinacidil, a Potassium-Channel Opener, on Biodistribution of Thallium-201 in Tumor-Bearing Mice ($K^+$ 통로개방제 Pinacidil이 종양이식 생쥐에서 Tl-201의 체내분포에 미치는 영향)

  • Lee, Jae-Tae;Chun, Kyung-Ah;Lee, Sang-Woo;Kang, Do-Young;Ahn, Byeong-Cheol;Jun, Soo-Han;Lee, Kyu-Bo;Ha, Jeoung-Hee
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.4
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    • pp.303-311
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    • 2000
  • Purpose: Thallium behaves similarly to potassium in vivo. Potassium channel opener (K-opener) opens ATP-sensitive $K^+$-channel located at cell membrane, resulting in potassium efflux from cytosol. We have previously reported that K-opener can alter biokinetics of Tl-201 in cultured cells and in vivo. Malignant tumor cells have high Na-K ATPase activity due to increased metabolic activities and dedifferentiation, and differential delineation of malignant tumor can be possible with Tl-201 imaging. K-opener may affect tumoral uptake of Tl-201 in vivo. To investigate the effects of pinacidil (one of the potent K-openers) on the localization of the tumor with Tl-201 chloride, we evaluated the changes in biodistribution of Tl-201 with pinacidil treatment in tumor-bearing mice. Materials and Methods: Baltic mice received subcutaneous implantation of murine breast cancer cells in the thigh and were used for biodistribution study 3 weeks later. $100{\mu}g$ of pinacidil dissolved in $200{\mu}l$ DMSO/PBS solution was injected intravenously via tail vein at 10 min after 185 KBq ($5{\mu}Ci$) Tl-201 injection. Percentage organ uptake and whole body retention ratio of Tl-201 were measured at various periods after injection, and values were compared between control and pinacidil-treated mice. Results: Pinacidil treatment resulted in mild decrease in blood levels of Tl-201, but renal uptakes were markedly decreased at 30-min, 1- and 2-hour, compared to control group. Hepatic, intestinal and muscular uptake were not different. Absolute percentage uptake and tumor to blood ratios of Tl-201 were lower in pinacidil treated mice than in the control group at all time points measured. Whole body retention ratio of Tl-201 was lower in pinacidil treated mice ($58{\pm}4%$ ), than in the control group ($67{\pm}3%$) at 24 hours after with injection of $100{\mu}g$ pinacidil. Conclusion: K-opener did not enhance, but rather decreased absolute tumoral uptake and tumor-to-blood ratios of Tl-201. Decreased whole body retention ratio and renal uptake were observed with pinacidil treatment in tumor-bearing mice.

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Quantitative Analysis of Thallium-201 Myocardial Tomograms (Thallium-201 심근 단층영상의 정량적 분석)

  • Kim, Sang-Eun;Nam, Gi-Byoung;Choi, Chang-Woon;Choi, Kee-Joon;Lee, Dong-Soo;Sohn, Dae-Won;Ahn, Cu-Rie;Chung, June-Key;Lee, Myoung-Mook;Lee, Myung-Chul;Park, Young-Bae;Choi, Yun-Shik;Seo, Jung-Don
    • The Korean Journal of Nuclear Medicine
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    • v.25 no.2
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    • pp.165-176
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    • 1991
  • The purpose of this study was to assess the ability of quantitative Tl-201 tomography to identify and localize coronary artery disease (CAD). The study population consisted of 41 patients (31 males, 10 females; mean age $55{\pm}7$ yr) including 14 with prior myocardial infarction who underwent both exercise Tl-201 myocardium SPECT and coronary angiography for the evaluation of chest pain. From the short axis and vertical long axis tomograms, stress extent polar maps were generated by Cedars-Sinai Medical Center program, and the % stress defect extent (SDE) was quantified for each coronary artery territory. For the purpose of this study, the coronary circulation was divided into 6 arterial segments, and the "myocardial ischemic score" (MIS) was calculated from the coronary angiogram. Sensitivity for the detection of CAD ($\geq50%$ coronary stenosis by angiography) by angiography) by stress extent polar map was 95% in single vessel disease, and 100% in double and triple vessel deseases. Overall sensitivity was 97%. Sensitivity and specificity for the detection of individual diseased vessels were, respectively, 87% and 90% for the left anterior descending artery (LAD), 36% and 93% for the left circumflex artery (LCX), and 71% and 70% for the right coronary artery (RCA). Concordance for the detection of individual diseased vessels between the coronary angiography and stress polar map was fair for the LAD (kappa=0.70), and RCA (kappa=0.41) lesions, whereas it was poor for the LCX lesions (kappa : 0.32). There were siginificant correlations between the MIS and SDE in LAD (rs=0.56, p=0.0027), and RCA territory (rs=0.60, p=0.0094). No significant correlation was found in LCX territory. When total vascular territories were combined, there was a significant correlation between the MIS and SDE (rs=0.42, p=0.0116). In conclusion, the quantitative analysis of Tl-201 tomograms appears to be accurate for determining the presence and location of CAD.

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Dual-Isotope SPECT Imaging with Thallium-201 and Technetium-99m MIBI in Detecting Coronary Artery Disease (관상동맥질환 진단에서 Thallium-201과 Technetium-99m MIBI를 이용한 Dual-Isotope SPECT 영상)

  • Lee, Gyu-Gwang;Cho, Ihn-Ho;Lee, Hyoung-Woo;Park, Jong-Sun;Won, Kyu-Chang;Sin, Dong-Gu;Kim, Young-Jo;Shim, Bong-Sup
    • Journal of Yeungnam Medical Science
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    • v.16 no.1
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    • pp.101-107
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    • 1999
  • We evaluated the results of sequential SPECT dual-isotope imaging with Tl-201 and Tc-99m MIBI in 24 patients. all of whom also had coronary angiography within the past one month. Coronary angiography showed that 12 patients had no CAD, 4 patients had one-vessel CAD, 7 patients had two-vessel CAD and 1 patient had three-vessel CAD. Serial studies of resting Tl-201 and dipyridamole stress Tc-99m MIBI were completed within 2 hours. When more than 50% of coronary artery narrowing was considered significant, the overall sensitivity and specificity of CAD detection were 91.7%. The sensitivity of CAD detection in patients with one-vessel and multi-vessel diseases was 75% and 100%. respectively. Therefore, sequential dual-isotope SPECT demonstrated high sensitivity and specificity for CAD detection. In conclusion, sequential dual-isotope imaging is feasible and can be completed in a short time and may therefore enhance laboratory throughput and patient convenience.

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Radiopharmaceuticals Used in Cardiac Imaging (심장영상에 이용되는 방사성의약품)

  • Hwang, Kyung-Hoon;Chung, Yong-An;Lee, Byeong-Il;Lee, Yu-Kyung;Lee, Min-Kyung;Choe, Won-Sick
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.3
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    • pp.174-178
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    • 2009
  • Many radiopharmaceuticals have been developed and wildy used in the imaging cardiac function. Myocardial perfusion imaging (MPI) is a well established noninvasive method of assessing coronary blood flow and has been widely used in patients diagnosed or suspected with coronary artery diseases. The innovation of radiopharmaceuticals used in the cardiac imaging is one of the most important contributors to the development of nuclear cardiology. Thallium-201 and various technetium-99m agents have been globally used for myocardial perfusion SPEG, and N-13 ammonia (13NH3), rubidium-82 (82Rb), 0-15 water (H2150) for myocardial perfusion PET. As well as the cardiac perfusion studies, new radiopharmaceuticals that visualize fat metabolism or receptors of the sympathetic nervous system have successfully been applied to clinical practice. Useful information can be obtained for diagnosing coronary artery disease, evaluating patients' condition, or assessing therapeutic effects. In this review, we describe the characteristics and clinical usefulness of radiopharmaceuticals used for cardiac SPEG and PET.

Radiolabelled Monoclonal Antibodies (McAb): An Alternate Approach to the Conventional Methods for the Assessment of Cardiomyocyte Damage in an Experimental Brain-Death Pig Model

  • Haider, Kh.H.;Stimson, W.H.
    • Archives of Pharmacal Research
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    • v.21 no.5
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    • pp.496-502
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    • 1998
  • The present study was carried out to determine the possible use of cTn-I in the cardiac myofibrillar architecture, as a potential target for in vivo radioimmunodetection of cardiac damage in a brain death pig model. Radioiodiantion of the anti-cTn-I 5F4 McAb was carried out by lactoperoxidase method. the percentage iodine incorporation achieved was 70-75%. The radioiodinated McAbs were purified on Sephadex G-25 column and characterised by Paper chromatography, Phast Gel electrophoresis and electroimmunoblotting. Radioiodinated anticTn-I 5F4 McAbs were employed alongside Pyrophosphate($Tc_{99m}$-PPi$) and $Thallium^{201}$ chloride($TI^{201}$) in 24 landrace pigs (brain-dead=18 & sham-operated=6). The percentage cardiac uptake of the radiolabelled antibody injected dose was significantly higher in the brain dead animals(0.196%) as compared to that of sham-operated animals (0.11%). Specific in vivo localization of radiolabelled McAbs in the infarcted cardiac tissue was confirmed by computer-aided reconstruction of 3-D images of the isolated heart. The preliminary results of the study revealed preferential uptake of radiolabelled antibody at the site of myocyte damage resulting from artificially induced brain death.

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AN INFRA-RED SPECTROPHOTOMETRIC STUDY OF THE REACTION IN CALCIUM HYDROXIDE DENTAL CEMENT (치과용(齒科用) 수산화(水酸化)칼슘 시멘트의 경화반응(硬化反應)에 관(關)한 적외선분석학적(赤外線分析學的) 연구(硏究))

  • Kim, Choong-Jong;Min, Byung-Soon;Choi, Ho-Young;Park, Sang-Jin
    • Restorative Dentistry and Endodontics
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    • v.10 no.1
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    • pp.71-83
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    • 1984
  • The purpose of this study was to evaluate the transmission spectrum of the set calcium hydroxide dental cement (Dycal, L.D. Caulk Co. Milford, Del.) Cement was prepared for A T R spectra at a low powder-to-liquid ratio of 3.0gm/ml in order to retard the reaction and facilitate the manipulation of loading the cement into the cell. Spectra were recorded on an I R Spectrophotometer (MX-1, FT) at an agle of incidence of 55. The A T R cell was a RIIc Model TR5 with a hemisperical KRS-5 (Thallium-Bromide-Iodide). A spectrum was recorded within 3 minutes. Further spectra were recorded after 5,10,30 minutes and 1,5,24, 72 hours. The results were as follows; 1. The setting reaction between acid paste and base past would take place fastly within 10 minutes after mix, and that would be slow until 72 hours after mix. 2. In the set cements, some methyl salicylate and calcium hydroxide remained unreacted until 72 hours after mix. 3. The setting reaction and the reaction rate occuring at the surface and in the bulk cements were similar. 4. The chelates were bound together between calcium hydroxide and methyl salicylate.

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