• The Korean Journal of Physiology and Pharmacology
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• v.9 no.4
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• pp.195-201
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• 2005

High extracellular glucose concentration was reported to suppress intracellular $Ca^{2+}$ clearing through altered sarcoplasmic reticulum (SR) function. In the present study, we attempted to elucidate the effects of pyruvate and fatty acid on SR function and reveal the mechanistic link with glucose-induced SR dysfunction. For this purpose, SR $Ca^{2+}$-uptake rate was measured in digitonin-permeabilized H9c2 cardiomyocytes cultured in various conditions. Exposure of these cells to 5 mM pyruvate for 2 days induced a significant suppression of SR $Ca^{2+}$-uptake, which was comparable to the effects of high glucose. These effects were accompanied with decreased glucose utilization. However, pyruvate could not further suppress SR $Ca^{2+}$-uptake in cells cultured in high glucose condition. Enhanced entry of pyruvate into mitochondria by dichloroacetate, an activator of pyruvate dehydrogenase complex, also induced suppression of SR $Ca^{2+}$-uptake, indicating that mitochondrial uptake of pyruvate is required in the SR dysfunction induced by pyruvate or glucose. On the other hand, augmentation of fatty acid supply by adding 0.2 to 0.8 mM oleic acid resulted in a dose-dependent suppression of SR $Ca^{2+}$-uptake. However, these effects were attenuated in high glucose-cultured cells, with no significant changes by oleic acid concentrations lower than 0.4 mM. These results demonstrate that (1) increased pyruvate oxidation is the key mechanism in the SR dysfunction observed in high glucose-cultured cardiomyocytes; (2) exogenous fatty acid also suppresses SR $Ca^{2+}$-uptake, presumably through a mechanism shared by glucose.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.219-225
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• 2008

Taurine is the most abundant amino acid in many tissues and is found to be enhancing the bone tissue formation or inhibits the bone loss. Although it is reported that taurine reduces the alveolar bone loss through inhibiting the bone resorption, its functions of taurine and expression of taurine transporter (TauT) in bone have not been identified yet. The purpose of this study is to clarify the uptake mechanism of taurine in osteoblast using mouse osteoblast cell lines. In this study, mouse stromal ST2 cells and mouse osteoblast-like MC3T3-E1 cells as osteoblast cell lines were used. The activity of taurine uptake was assessed by measuring the uptake of [$^3H$]taurine in the presence or absence of inhibitors. TauT mRNA was detected in ST2 and MC3T3-E1 cells. [$^3H$]Taurine uptake by these cells was dependent on the presence of extracellular calcium ion. The [$^3H$]taurine uptake in ST2 cells treated with 4 mM calcium was increased by 1.7-fold of the control which was a significant change. In contrast, in $Ca^{++}$-free condition and L-type calcium channel blockers (CCBs), taurine transport to osteocyte was significantly inhibited. In oxidative stress conditions, [$^3H$]taurine uptake was decreased by TNF-$\alpha$ and $H_2O_2$. Under the hyperosmotic conditions, taurine uptake was increased, but inhibited by CCBs in hyperosmotic condition. These results suggest that, in mouse osteoblast cell lines, taurine uptake by TauT was increased by the presence of extracellular calcium, whereas decreased by CCBs and oxidative stresses, such as TNF-$\alpha$ and $H_2O_2$.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.255-262
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• 2000

This study was carried out to investigate the physiological changes induced acutely with the low doses of lead acetate in the synaptosomes from the cerebrum and brain stem of the rat. The general uptake patterns of [$^3$H]-serotonin were observed in synaptosomes, as a model of presynaptic nerve terminal, from the cerebrum and brain stem. And the effects of the low doses of lead acetate on the uptake process were investigated id vitro and in vivo. The Km value of the uptake of the [$^3$H]-serotonin by the synaptosomes was 0.5 $\mu$M in the cerebrum and 0.1 $\mu$M in the brain stem. These low values reveal that the synaptosomes from the cerebrum and the brain stem have a high affinity to [$^3$H]-serotonin, especially in brain stem. The uptake of $\mu$M-serotonin was dependant on the sodium and potassium ions. When being treated with ouabain, the $Na^+$ $-K^+$ ATPase inhibitor, the uptake of [$^3$H]-serotonin was reduced. This supports strongly that the uptake of [$^3$H]-serotonin was sensitive to the changes of the concentrations of the sodium and potassium ions. When the calcium channel blocker, verapamil, was treated, the uptake of [$^3$H]-serotonin was changed only in synaptosomes from the brain stem. The uptake of [$^3$H]-serotonin was reduced by the lead treatment in the synaptosomes from the cerebrum and brain stem in vitro and in vivo. [lead acetate, synaptosomes, $^3$H-serotonin, rat]

• Journal of Magnetics
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• v.19 no.4
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• pp.372-377
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• 2014

The purpose of the study is to investigate how uptake counts of $^{201}Tl$ of radioisotopes in the human body could change, when taking computed tomography and magnetic resonance imaging right after injecting contrast media. $^{201}Tl$ radioisotope substances of iodine contrast medium, which is a computed tomography contrast medium, and paramagnetic contrast medium, which is an magnetic resonance imaging contrast medium, were used as study materials. First, $^{201}Tl$ was put into 4 cc of normal saline in test tube, and then a computed tomography contrast medium of Iopamidol$^{(R)}$ or Dotarem$^{(R)}$, was put into 2 cc of normal saline in test tube. An magnetic resonance imaging contrast medium of Primovist$^{(R)}$ or Gadovist$^{(R)}$ was also put into 2 cc of normal saline in test tube. Each contrast medium was distributed to make $^{201}Tl$ as 3 mCi, with a total of 4 cc. Gamma camera, low energy high resolution collimator, and pinhole collimator were used to obtain images. The uptake count of $^{201}Tl$ was measured with 1000 frames of images, and obtained after 10 times of repetition. This study revealed that the use of Gadovist$^{(R)}$, which is an magnetic resonance imaging contrast medium, showed the smallest number of uptake count, after measuring $^{201}Tl$ uptake count by low energy high resolution collimator. On the other hand, the use of Iopamidol$^{(R)}$, which is a computed tomography contrast medium, showed the biggest difference in uptake count, when measuring $^{99m}Tc$ uptake count by Pinhole collimator. When examining with gamma camera, using contrast medium and $^{201}Tl$, identifying the changes of uptake count is very important for improving the value of diagnosis.

• Journal of Environmental Science International
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• v.12 no.8
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• pp.853-860
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• 2003

Plants sequester atmospheric CO$_2$, a major agent of climate change, during the growing periods and mitigate its rising accumulation in the atmosphere. Pinus densiflora and Quercus mongolica are the native tree species dominant in the temperate forests of Korea. This study quantified the annual CO$_2$ uptake by the two species at forest sites in Chuncheon in the middle of the country. The quantification was based on seasonal measurements of CO$_2$ exchange rates under natural conditions by an infrared gas analyzer over the growing season (1999). The monthly CO$_2$ uptake per unit leaf area ranged from 1.6-6.7 mg/d㎡/h for P. densiflora and from 3.7-8.9 mg/d㎡/h for Q. mongolica, with a maximum in mid-summer. An equation for each species was generated to estimate easily the annual CO$_2$ uptake by total leaf area per tree, which subtracted the CO$_2$ release (i.e. respiration) by leaves and woody organs from the gross CO$_2$ uptake (diurnal uptake and release by leaves). Annual CO$_2$ release by leaves and woody organs accounted for 58-73％ of the gross CO$_2$ uptake across tree specimens. Annual CO$_2$ uptake per tree increased with increasing dbh (stem diameter at breast height) for the study diameter range, and was greater for Q. mongolica than for P. densiflora in the same dbh sizes. This was mainly associated with a greater total leaf area in the former. For example, the annual CO$_2$ uptake by one tree with dbh of 25 cm was 35.6 kg/yr for P. densiflora and 47.9 kg/yr for Q. mongolica. The results from this study can be applied to evaluate an atmospheric CO$_2$ reduction of woody plants by forest type and age class.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.66-70
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• 2008

Reports about FDG PET in biliary tumor are limited and there are almost no reports regarding its efficacy. Biliary tumor is divided to intrahepatic and extrahepatic bile duct cancer, and intrahepatic bile duct cancer can be further divided to peripheral type which occurs at lobular duct and hilar type which occurs at hepatic hilum. Surgical resection is the only curative method for bile duct tumor, and accurate staging plays an important role in deciding treatment modality. Among intrahepatic bile duct tumors, peripheral type and hilar type have the same histological characteristics, but different clinical manifestations and tumor growth pattern. On PET image, FDG uptake is also different between peripheral type and hilar type. Most of the former shows high FDG uptake at primary and metastasis site so it is very useful for determining stage and changing treatment plans. However, the later is diversified among low uptake and very high uptake. The FDG uptake pattern of hilar type is similar to that of extrahepatic bile duct cancer, and mucinous component is an important factor, which affects FOG uptake. When tumor cells are scattered in desmoplatsic stroma, then FDG uptake is low as well. In contrast, when FDG uptake is high, it is likely to be tubular type which has high tumor density. Tumor growth pattern also affects FDG uptake. Nodular type mostly takes higher FDG compared to infiltrative type. There are many cases where benign inflammatory diseases take high FDG that PET alone can not distinguish malignant lesion from benign lesion. In conclusion, studies about PET using FDG are still limited. Thus, it is hard to make accurate conclusion about the roles of PET or PET/CT in biliary cancers, but peripheral type intrahepatic bile duct cancers and mass forming hilar and extrahepatic bile duct cancers appear to be good indications performing FDG PET or PET/CT.

• The Korean Journal of Nuclear Medicine
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• v.26 no.2
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• pp.360-364
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• 1992

Treatment for the brain tumors consist of surgery, chemotherapy, and a variety of methods of irradiation. Therapy is aimed to destroy the tumor, but necrosis and edema occur concurrently. Conventional structural imaging techniques such as CT or MRI are unable to reliably distinguish persistent and recurrent tumor from necrosis or edema. T1-201 has been shown to be useful in the evaluation of the myocardial viability by comparing the early uptake and redistribution image. The aim of this study is to evaluate the clinical usefulness of the early uptake and delayed washout images of the T1-201 brain SPECT in the brain tumors. In the pathologically diagnosed various brain tumor patients, brain SPECT was done with rotating gamma camera 15 minutes and 3 hours after T1-201 injection, and the T1-201 uptake in the tumor was compared with the skull and scalp activity. In the glioblastoma multiforme, meningioma and metastatic tumor, the T1-201 uptake was higher than low grade glioma in both 15 minute and 3 hour images (p<0.02). In the low grade glioma,3 hour T1-201 uptake was significantly lower than 15 minute uptake (p<0.05) but in the glioblastoma, meningioma and metastatic tumor there was no significant difference. There was no significant difference in the T1-201 uptake among the glioblastoma, meningioma and metastatic tumors. In one matastatic tumor, T1-201 uptake was decreased after radiation therapy. T1-201 brain SPECT could distinguish the benign and malignancy, and seems to be useful in the follow-up after treatment. But one of the early or delayed SPECT seems not to be necessary for these purposes.

• Journal of Environmental Impact Assessment
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• v.18 no.1
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• pp.41-50
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• 2009

Using the "Statistical Yearbooks of Korean forestry", we assessed the uptake of nitrogen and base cations by Korean forest. Combined amount of base cations uptake by forest tress during its growth and that of at the time of harvest reached to 1,034 eq/ha/yr. The base cations uptake in the range of 900 ~ 1,100 eq/ha/yr occupied approximately 48.6% out of total. Coniferous forest in the range of 170 ~ 200 eq/ha/yr was 59.9%, deciduous forest in the range of 430 ~ 530 eq/ha/yr was 42.6%, and mixed forest in the range of 270 ~ 370 eq/ha/yr was 35.7% out of total. Deciduous forest recorded higher uptake rate of nitrogen and base cation than coniferous forest in Korea. Combined amounts of nitrogen uptake by forest tress during growth and that at the time of forest, was 1,108 eq/ha/yr and nitrogen uptake was in the range of 1,000 ~ 1,200 eq/ha/yr, Within Korea, forest with nitrogen uptake in the range of 1,000 ~ 1,200 eq/ha/yr account for 45.7% of the entire country. Locations in the range of 320 ~ 390 eq/ha/yr occupied 43.9% of all coniferous forest while deciduous forest in the range of 470 ~ 570 eq/ha/yr was 40.4% of total deciduous forest. As for mixed forest in the range of 270 ~ 370 eq/ha/yr, it occupied 35.9% of all mixed forest of Korea.

• Journal of Ginseng Research
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• v.17 no.3
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• pp.240-245
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• 1993

This study was conducted with ginseng plants to investigate photosynthetic response to changes of light intensity and leaf temperature. $CO_2$ uptake in diurnal course was highest in the first phase (8 00~5 : 30 Am.) on May 30, 1992. In $CO_2$ uptake related to stomatal conductance, these relationship was synchronized in diurnal course, but relationship between TEX>$CO_2$ uptake and intercellular $CO_2$ concentration in diurnal course was synchronized oppositely. Leaf temperature and light intensity at the highest $CO_2$ uptake were in the range of 23~$24^{\circ}C$) and 95$\mu$mol.$m^{-2}$.$s^{-1}$), $CO_2$ , respectively. In response to an increasing light intensity under a constant leaf temperature ($18^{\circ}C$), $CO_2$ uptake was increased throughout the light intensity sequence up to 250$\mu$mol.$m^{-2}$.$s^{-1}$), $CO_2$ When $CO_2$ uptake was measured with a series of leaf temperature under a constant light intensity (250 $\mu$mol.$m^{-2}$.$s^{-1}$), $CO_2$ uptake was highest at $18^{\circ}C$ as a 4.1$\mu$mol.$m^{-2}$.$s^{-1}$), $CO_2$ . Similar changes were also observed in stomatal conductance and intercellular $CO_2$ concentration. Evidences from several approaches indicate that synchronization of $CO_2$ uptake, stomatal conductance and intercellular $CO_2$ concentration were closely inter-related and changes of leaf temperature iuluenced the photo-response in photosynthetic processes.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.533-538
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• 2021

^99mTcO₄^- is used to measure thyroid uptake. When measuring background radioactivity of the thigh, the distance between the detector and the thigh was 20 cm at a position 10 cm above the knee from the knee to the pelvis. At 25 cm, many hospitals are measuring at different distances. The purpose of this study was to study the difference in effectiveness in obtaining the thyroid uptake rate by quantitatively analyzing the uptake rate measurement at two distances. As a result, the average thyroid uptake rate measured at 20 cm in the thigh of 50 patients was 3.532±4.312%, and the average thyroid uptake rate measured at 25 cm was 3.680±4.304%. As a result of the thyroid uptake rate test result, the femoral background radioactivity value measured at a distance of 20 cm was relatively higher than the background radioactivity value measured at a distance of 25 cm, and as a result, the thyroid uptake rate was 0.148% lower.