• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.72-77
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• 2013

Purpose: Whole-body PET using radiopharmaceutical is one of the imaging study methods for physiological changes of body. High specificity of the PET-CT examination is used to detect an early stages of cancer and metastatic cancer by imaging a physiological changes. During the imaging process, PET image has been characterized by a relatively low image quality due to its low sensitivity and the acquisition of random and scatter coincidences as well as patients figure. Therefore, the image quality as the changes of the acquisition times of patient weight was evaluated in this study. Materials and Methods: Thirty patients who presented to our hospital were enrolled. They were divided to normal, overweight, and obese group using BMI index, respectively. The patients with a liver disease and diabetes were excluded. $^{18}F-FDG$ was administered to the patients as 5.2 MBq per kg. After an hour from an injection, image acquisition was obtained as List mode in a part of liver in 1 bed. SNR (signal-to-noise ratio) of each groups acquisition times were confirmed from the calculated radiation counts and random fractions. The statistical significance of three groups was confirmed through one-way ANOVA test. On the basis of the counts of 2 minutes on normal group, the SNR of overweight group and obese group were compared. Results: The SNR were increased with loger aquisition time in 3 groups. In the condition of same acquisition time, the SNR had a statistical significance (P<0.05). The SNR were decreased to the normal, overweight, and obese, respectively. Liver activity had no significance difference on each group and RF had the significance differences (P<0.05). On the basis of the counts of 2 minutes on normal group, there were no statistical significance in a three minute acquisitions of overweight group and two minute acquisitions of obese group (P=0.150). Conclusion: In this study, the administrated amount of radiation dose did not adjust as the change of the patients weight. Increasing the acquisition time when the administration of the same amount of dose was able to get a good result of SNR. When the Based 2 minute on normal group, if overweight and obese case the increased acquisition time of 3 minute was able to obtain a similar SNR. On the basis of the normal group, the acquisition times of overweight and obese group were increased to 3 minutes per bed and the SNR were similar to the normal group.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.528-535
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• 2020

Recently, the protection coordination method of DC systems has been presented because renewable energy and distributed resources are being installed and operated in distribution systems. On the other hand, it is difficult to detect ground faults because there is no significant difference compared to a steady-state current in ungrounded IT systems, such as DC load networks and urban railways. Therefore, this paper formulates the detection principle of IMD (Insulation Monitoring Device) to use it as a protection coordination device in a DC system. Based on the signal injection method of IMD, which is analyzed by a wavelet transform, this paper presents an algorithm of detecting ground faults in a DC system in a fast and accurate manner. In addition, this paper modeled an IMD and an ungrounded DC system using the PSCAD/EMTDC S/W and performed numerical analysis of a wavelet transform with the Matlab S/W. The simulation results of a ground fault case in an ungrounded DC system showed that the proposed algorithm and modeling are useful and practical tools for detecting a ground fault in a DC system.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.292-297
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• 2007

Purpose : Kawasaki disease (KD) rarely occurs in school-aged children. We clarified the characteristics of KD in this age group to provide tips for a high index of suspicion. Methods : Features of 38 patients with KD who were 7 years of age or older were retrospectively reviewed. Results : The incidence of the KD patients ${\geq}7years$ was 4.9 percent. The ratio of male to female was 2.5:1. Of the 38 patients, nine patients (24.0 percent) were diagnosed with typical KD and 29 patients (76.0 percent) with incomplete KD. In incomplete KD patients, cervical lymphadenopathy (69.0 percent) occurred most frequently, followed by conjunctival injection (62.0 percent) and polymorphous rash (45.0 percent). These patients occasionally presented with other additional symptoms including abdominal pain, headache, vomiting and arthralgia. Incomplete KD was initially diagnosed as cervical lymphadenitis (34.0 percent), viral infection (14.0 percent), scarlet fever (7.0 percent), meningitis (7.0 percent), and Kikuchi disease (7.0 percent). Coronary complications were noted in 15 patients (39.0 percent). Of the 37 patients treated with intravenous immunoglobulin, five (14.0 percent) were resistant to the therapy and all had coronary abnormalities. Conclusion : Most patients with KD ${\geq}7years$ of age have incomplete presentations. They tend to have a higher incidence of initial presentations of unilateral neck mass and coronary artery involvement. In school-aged children, fever and cervical lymphadenitis or suspected neck infection unresponsive to intravenous antibiotics should signal the possibility of KD. A high index of suspicion and prompt treatment is essential in this age group of patients.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.307-312
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• 1994

Interictal single photon emission computed tomography of regional cerebral blood flow (rCBF SPECT) in 18 intractable temporal lobe epilepsy patients(8 male and 10 female patients: average 23.5 years old) were compared with 2.0 T magnetic resonance imaging (MRI). And surgical outcome was analysed with the findings, symptom duration and lateralization of temporal lobe. Preoperatively rCBF SPECT was done in all 18 patients with intravenous injection of 740 MBq 99mTc-HMPAO. MRI was also done preoperatively in 13 patients. Surgical outcome was classified by Engel's outcome classification(four-part classification recommended at the first Palm Desert conference). rCBF SPECT detected correctly lateralising abnormality of temporal lobe hypoperfusion in 13/18(72.2%), contralateral temporal lobe hypoperfusion in 2/18(11.1%) and showed no def-inite abnormality in 3/18(16.7%). The positive predictive value of unilateral temporal lobe hypoperfusion was 87%. MRI detected correct localising abnormality in 8/13(61.5%), such as hippocampal atrophy(7/13), asymmetric temporal horn(6/13), anterior temporal lobe atrophy(1/13), increased signal intensity from hippocampus(1/13) and calcific density(1/13), and no abnormal finding was noted in 5/13(38.5%). There was no false positive findings and the positive predictive value of MRI was 100%. Only 2 cases showed same lateralization findings in rCBF SPECT and MRI. There was no significant correlation between symptom duration and no abnormal findings on SPECT or MRI. Surgical outcome showed class I in 15/18(83.3%), and class II in 2/18(11.1%). One case of no abnormal finding in both SPECT and MRI showed class III surgical outcome. No class IV surgical outcome was noted. Surgical outcome, lateralization of epileptic focus in temporal lobe and abnormal findings in rCBR SPECT or MRI were not significantly correlated.

• Applied Microscopy
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• v.41 no.1
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• pp.37-45
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• 2011

Known as a female hormone, estrogen, has an effect on the male reproductive organs. The estrogen has to combine with the estrogen receptor to communicate a signal. Propyl pyrazole triol (PPT) is an estrogen receptor alpha selective agonist with a 410-, or 1,000-fold relative binding affinity for estrogen receptor alpha versus estrogen receptor beta. In this study, adult male mice were treated weekly with subcutaneously injections of PPT (0.01 mg, 0.1 mg, 1mg and 4 mg) suspended in castor oil (as control) for 8 weeks and observed histologically changes in testis, efferent ductule and epididymis. In the high concentrations of PPT 4 mg treatment group, a remarkable reduction was observed in the weight of the body, testis and epididymis. Microscopic examination revealed a reduction in seminiferous tubular diameter of the testis, and epithelial cell height of the epididymis in treated group during the experiment. In addition, as the diameter of the efferent ductule increased gradually, the height of epithelial cells was decreased. PPT 4 mg treatment group caused inhibition of spermatogenesis due to atrophied germinal epithelium in the testis, and decrease of adipocyte size attached to the epididymis. Sperm was not observed in the caudal epididymis of PPT 4 mg treated group. In conclusion, the injection of high concentrations of PPT into adult male mice induced physiological changes, such as an inhibition of spermatogenesis, and also histological changes within the reproductive organs.

• Korean Journal of Optics and Photonics
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• v.28 no.1
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• pp.9-15
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• 2017

We precisely measured and analyzed the dynamics of peptide-antibody interactions, using an ellipsometric biosensor based on a silicon substrate. To reduce the signal error due to the imperfect flatness of the substrate for extremely low concentrations of peptide, we fabricated the biosensor with a silicon substrate coated with Dextran SAM, instead of a glass prism coated with a thin metallic thin film. At an injection speed of $100{\mu}l/min$ of buffer liquid, we detected the dynamics of antibody-Dextran SAM or peptide-antibody fixed on biosensor, respectively. We detected the dynamics of antibody-Dextran SAM interactions down to a low concentration of 5 ng per liter, and we precisely measured the dynamics of association and dissociation of peptide and antibody down to 100 nM of peptide. We obtained the rate constants for association and dissociation from fitting the data by using deduced dynamical equation. As a result, we obtained an equilibrium constant for dissociation of 97 nM of peptide-antibody complex, which belongs to Class I.

• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.902-909
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• 1995

Detection limit as well as calibration curves on organophosphorus pesticide(dimethoate, diazinon, parathion-methyl, fenitrothion, malathion) and BHCs were measured for evaluation of utility on qualitative or quantitative analysis of pesticides with ion Trap mass spectrometer and quadrupole mass spectrometer. As ionization source, EI and CI were adopted for qualitative analysis of pesticides by comparison of each fragmentation pattern. At the same time, the utility as trace analysis techniques through scan or selected ion monitoring(SIM) mode was evaluated. With ion trap for all pesticides, detection limit(DL, 1 ${\mu}L$ injection) on scan mode was ranged 0.008∼0.225 ng at signal to noise ratio 3. With quadrupole DL on scan mode was ranged 0.23∼3.1 ng over 0.032∼0.68 ng on SIM mode. The calibration curve with ion trap generated good linearity over 0.99 as correlation coefficient. As clean up procedure, Bio Beads S-X3 was used for the separation of oils from five organophosphorous pesticides in flour extractant showing more than 80% as recovery at most cases. In case of BHCs in jinseng with Florisil column, the recovery of pesticides has been 60% to 90%.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1529-1536
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• 2006

We cloned a gene of ompH(D:4) from pigs infected with P. multocida D:4 in Korea [16]. The gene is composed of 1,026 nucleotides coding 342 amino acids (aa) with a signal peptide of 20 aa (GenBank accession number AY603962). In this study, we analyzed the ability of the ompH(D:4) to induce protective immunity against a wild-type challenge in mice. To determine appropriate epitope(s) of the gene, one full and three different types of truncated genes of the ompH(D:4) were constructed by PCR using pET32a or pRSET B as vectors. They were named ompH(D:4)-F (1,026 bp [1-1026] encoding 342 aa), ompH(D:4)-t1 (693 bp [55-747] encoding 231 aa), ompH(D:4)-t2 (561 bp [187-747] encoding 187 aa), and ompH(D:4)-t3 (540 bp [487-1026] encoding 180 aa), respectively. The genes were successfully expressed in Escherichia coli BL21(DE3). Their gene products, polypeptides, OmpH(D:4)-F, -t1, -t2, and -t3, were purified individually using nickel-nitrilotriacetic acid (Ni-NTA) affinity column chromatography. Their $M_rs$ were determined to be 54.6, 29, 24, and 23.2 kDa, respectively, using SDS-PAGE. Antisera against the four kinds of polypeptides were generated in mice for protective immunity analyses. Some $50{\mu}g$ of the four kinds of polypeptides were individually provided intraperitoneally with mice (n=20) as immunogens. The titer of post-immunized antiserum revealed that it grew remarkably compared with pre-antiserum. The lethal dose of the wild-type pathogen was determined at $10{\mu}l$ of live P. multocida D:4 through direct intraperitoneal (IP) injection, into post-immune mice (n=5, three times). Some thirty days later, the lethal dose ($10{\mu}l$) of live pathogen was challenged into the immunized mouse groups [OmpH(D:4)-F, -t1, -t2, and -t3; n=20 each, two times] as well as positive and negative control groups. As compared within samples, the OmpH(D:4)-F-immunized groups showed lower immune ability than the OmpH(D:4)-t1, -t2, and -t3. The results show that the truncated-OmpH(D:4)-t1, -t2, and -t3 can be used for an effective vaccine candidate against swine atrophic rhinitis caused by pathogenic P. multocida (D:4) isolated in Korea.

• Korean Journal of Medicinal Crop Science
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• v.25 no.4
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• pp.231-237
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• 2017

Background: Cisplatin is one of the most extensively used chemotherapeutic agents for the treatment of cancer, including bladder, and ovarian cancers. However, it has been shown to induce nephrotoxicity, despite being an outstanding anti-cancer drug. In this study, we investigated the protective effect of dopaol ${\beta}$-D-glucoside (dopaol) on cisplatin-induced nephrotoxicity. Methods and Results: To confirm the protective effect of dopaol on cisplatin-induced nephrotoxicity, HK-2 cells were treated with $20{\mu}M$ cisplatin and $80{\mu}M$ dopaol. Cisplatin increased apoptosis, caspase-3 activity and mitochondrial dysfunction; however pretreatment with $80{\mu}M$ dopaol successfully attenuated apoptosis, caspase-3 activity and mitochondrial dysfunction. To evaluate the protective effect dopaol on cisplatin-induced nephrotoxicity in vivo, we used an animal model (balb/c mice, 20 mg/kg, i.p. once/day for 3 day). The results were similar to those obtained using HK-2 cells; renal tubular damage and neutrophilia induced by cisplatin reduced following dopaol injection (10 mg/kg, i.p. once/day for 3 day). Conclusions: These results indicate that dopaol treatment reduced cisplatin-induced nephrotoxicity in vitro and in vivo, and can be used to treat cisplatin-induced nephrotoxicity. However, further studies are required to determine the toxicity high dose dopaol and the signal pathways involved in its mechanism of action in animal models.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.207-213
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• 2019

The fuel-cut coast-down driving mode is activated when the acceleration pedal is released with transmission gear engaged, and it's a default function for electronic-controlled engine of vehicles. The fuel economy becomes better because fuel injection stops during fuel-cut driving mode. A fuel-cut detection method is suggested in the study and it's based on the speed, acceleration and road gradient data from GPS sensor. It detects fuel-cut driving mode by comparing calculated acceleration and realtime acceleration value. The one is estimated with driving resistance in the condition of fuel-cut driving and the other is from GPS sensor. The detection accuracy is about 80% when the method is verified with road driving data. The result is estimated with 9,600 data set of vehicle speed, acceleration, fuel consumption and road gradient from test driving on the road of 12km during 16 minutes, and the road slope is rather high. It's easy to detect fuel-cut without injector signal obtained by connecting wire. The detection error is from the fact that the variation range of speed, acceleration and road gradient data, used for road resistance force, is larger than the value of fuel consumption data.