• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.842-851
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• 1996

Background : Rifampicin(RFP) is a key component of the antituberculous shon-course chemotherapy and the RFP-resistance is a marker of multi-drug resistant(MDR) M. tuberculosis. rpoB gene encodes the ${\beta}$-subunit of RNA polymerase of M. tuberculosis which is the target of RFP. Recent reports show that rpoB gene mutations are the cause of RFP resistance of M. tuberculosis and the main mechanism of rpoB gene mutation is point mutation. And PCR-SSCP is a rapid and easy method for detecting point mutations. So we performed PCR-SSCP of rpoB gene of M. tuberculosis and compared the result with traditional RFP sensitivity test. Method : The 27 RFP sensitive M. tuberculosis culture isolates and 25 RFP resistant isolates were evaluated. The RFP sensitivity test was done at the Korean Tuberculosis istitute. The DNA was extracted by bead beater method and was amplified with primers TR-8 and TR-9 in a 20ul PCR reaction containing 0.1ul(luCi) [${\alpha}-^{32}P$] - dCTP. After amplification, SSCP was done using non-denaturaring polyacrylamide gel electrophoresis. Then direct sequencing was done in cases of different eletrophoretic mobility compared with that of H37Rv. In 19 cases, we compared PCR-SSCP results with patient's clinical course and the results of traditional RFP sensitivity test. Results : 1) All 27 RFP sensitive M. tuberculosis isolates showed the same electrophoretic mobility compared with that of H37Rv. And all 25 RFP resistant M. tuberculosis isolates showed different electrophoretic mobility. 2) The mechanism of rpoB gene mutation of M. tuberculosis is mainly point mutation. 3) The PCR-SSCP results correlate well with traditional RFP sensitivity and patient's clinical response to antituberculous treatment. Conclusion: The PCR-SSCP of rpoB gene is a very sensitive and rapid mehod in detecting RFP- resistant M. tuberculosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.796-801
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• 2001

A total of 277 mineral spring water samples in Kangwon province from 1999 to 2000 were analyzed for the presence of Yersinia spp. by the conventional Food and Drug Administration protocol, and presumptive strains were identified by morphological, cultural and biochemical tests according to Bergey’s manual. Also, the biotypes, serotypes, and susceptibility to 12 antibiotics were tested. Among the total 277 mineral spring water samples, 40 samples (14.4%) were found to be contaminated with Yersinia species. Among the 40 strains of Yersinia spp. isolates, 33 strains (82.5%) for Yersinia enterocolitica, 4 strains (10%) for Yersinia frederiksenii, 2 strains (5%) for Yersinia intermedia, and 1 strain (2.5%) for Yersinia sakazaki were identified, respectively. Of 40 Yersinia spp. isolates, Yersinia enterocolitica (82.5%) was the most predominant species in the mineral spring water samples compared to other Yersinia species. Compared to direct culture method after KOH treatment and KOH treatment method after cold enrichment for better isolation ratio of according to comparision of Yersinia species, the detection ration (18.5%) of KOH treatment method after cold enrichment was about 3 times better than that (6.1%) of direct culture method after KOH treatment. According to serotypes of Y. enterocolitica isolates, O : 5 (12.9%) was the most predominant and followed by O : 3 (9.7%), O : 8 (6.5%), and O : 9 (3.2%), and others. For biotypes of Y. enterocolitica isolates, 1A (71.0%) was the most predominantly abundant and followed by 3A (12.9%), 3B (9.7%), 1B (3.2%) and 5 (3.2%). Also, an antibiotic susceptibility test showed that Yersinia spp. isolates were very susceptible to the antibiotics tested, but they were very strongly resistant to ampicillin, cephalothin and carbenicillin.

• Applied Microscopy
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• v.30 no.4
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• pp.347-355
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• 2000

Zinc is one of the most abundant oligoelements in the living cell. It appears tightly bound to some metalloproteins and nucleic acids, loosely bound to some metallothioneins or even as free ion. Small amounts of zinc ions (in the nanomolar range) regulate a plentitude of enzymatic proteins, receptors and transcription factors, thus rolls need accurate homeostasis of zinc ions. Zinc is an essential catalytic or structural element of many proteins, and a signaling messenger that is released by neural activity at many central excitatory synapses. Growing evidences suggest that zinc may also be a key mediator and modulator of the neuronal death associated with transient global ischemia and sustained seizures, as well as perhaps other neurological disease stoles. Some neurons have developed mechanisms to accumulate zinc in specific membrane compartment ('vesicular zinc') which can be evidenced using histochemical techniques. Substances giving a bright colour or emitting fluorescence when in contact with divalent metal ions are currently used to detect them inside cells; their use leads to the so called 'direct' methods. The fixation and precipitation of metal ions as insoluble salt precipitates, their maintenance along the histological process and, finally, their demonstration after autometallographic development are essential steps for other methods, the so called 'indirect methods'. This study is a short report on the autometallograhical approaches for zinc detection in the central nervous system (CNS) by means of a modified selenium method.

• Clinical and Experimental Pediatrics
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• v.45 no.2
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• pp.183-191
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• 2002

Purpose : X-linked agammaglobulinemia(XLA) is an immunodeficiency caused by abnormalities in Bruton's tyrosine kinase(Btk), and is characterized by a deficiency of peripheral blood B cells. We studied the cytoplasmic expression of Btk protein and analyzed the Btk gene in peripheral blood mononuclear cells from two siblings and one cousin with XLA, as well as additional family members. Methods : Btk protein expression was analyzed by flow cytometry. Isolation of the coding sequence of the Btk gene was performed by amplification using the reverse transcription-polymerase chain reaction(RT-PCR) technique. Sequence alterations were screened by the single-stranded conformation polymorphism(SSCP) method and characterized by standard sequencing protocols. Results : Cytoplasmic expression of Btk protein in monocytes was not detected in three patients with XLA. In addition, Btk protein analysis clearly showed cellular mosaicism in monocytes from four obligate carriers, findings further supported by SSCP. A single base pair mutation(T to C) in Btk-exon three, which encodes the PH domain, was identified in four XLA patients. A diagnostic sequencing analysis was established to detect heterozygotic pattern in 4 carrier females. Furthermore, we found significant clinical heterogeneity in individuals with the same gene mutation. Conclusion : The implicating genetic alteration provided valuable clues to the pathogenesis of XLA in Korea and the flow cytometric analysis was suggested as a useful tool for rapid detection of XLA patients and carriers. The present study has identified a genetic mutation in the Btk coding region and demonstrated heterogeneity in clinical manifestations among patients with the same mutation. A flow cytometric analysis was found to be informative in establishing a deficiency of Btk protein in both patients and carriers and is recommended as a frontline procedure in the molecular diagnosis and work-up of XLA.

• Tuberculosis and Respiratory Diseases
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• v.60 no.2
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• pp.171-179
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• 2006

Background : Despite the emerging danger of MDR-TB to human beings, there have only been a limited number of drugs developed to treat MDR-TB since 1970. This study investigated the cross-resistance rate between rifampicin (RFP) and rifabutin (RBU) in order to determine the efficacy of rifabutin in treating MDR-TB. In addition, the results of rifabutin were correlated with the rpoB mutations, which are believed to be markers for MDR-TB and RFP resistance. Methods : The MICs of RBU were tested against 126 clinical isolates of MDR-TB submitted to the clinical laboratory of National Masan TB Hospital in 2004. Five different concentrations ($10-160{\mu}g/ml$) were used for the MICs. The detection of the rpoB mutations was performed using a RFP resistance detection kit with a line probe assay(LiPA), which contains the oligonucleotide probes for 5 wide type and 3 specific mutations (513CCA, 516GTC, and 531TTG) The rpoB mutation was determined by direct sequencing. Results : The rate of cross-resistance between RFP and RBU was 70.5%(74/105) at $20{\mu}g/ml$ RBU(ed note: How much RFP?) Most mutations (86.3%) occurred in the 524~534 codons. The His526Gln, His526Leu, Leu533Pro, Gln513Glu, and Leu511Pro mutations(Ed note: Is this correct?) were associated with the susceptibilty to RBU. Conclusion : Based on the cross-resistance rate between RFP and RBU, RBU may be used effectively in some MDR-TB patients. Therefore, a conventional drug susceptibility test for RBU and a determination of the critical concentration are needed. However, rpoB gene mutation test may be have limited clinical applications in detecting RBU resistance.

• Journal of the Korean Society of Radiology
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• v.5 no.2
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• pp.93-96
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• 2011

Currently, the development of direct conversion radiation detector using photoconductor materials is progressing in widely. Among of theses photoconductor materials, mercuric iodide compound than amorphous selenium has excellent absorption and sensitivity of high energy radiation. Also, the detection efficiency of signal generated in photoconductor film varies by electric filed and geometric distribution according to top-bottom electrode size. Therefore, in this work, the x-ray detection characteristics are investigated about the size of top electrode in $HgI_2$ photoconductor film. For sample fabrication, to solve the problem that is difficult to make a large area film, we used the spatial paste screen-print method. And the sample thickness is $150{\mu}m$ and an film area size is $3cm{\times}3cm$ on ITO-coated glass substrate. ITO(Indium-Tin-Oxide) electrode was used as top electrode using a magnetron sputtering system and each area is $3cm{\times}3cm$, $2cm{\times}2cm$ and $1cm{\times}1cm$. From experimental measurement, the dark current, sensitivity and SNR of the $HgI_2$ film are obtained from I-V test. From the experimental results, it shows that the sensitivity increases in accordance with the area of the electrode but the SNR is decreased because of the high dark current. Therefore, the optimized size of electrode is importance for the development of photoconductor based x-ray imaging detector.

• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.121-138
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• 2011

More affordable and available cutting-edge technologies (e.g., wireless vehicle communication) are regarded as a possible alternative to the fixed infrastructure-based traffic information system requiring the expensive infrastructure investments and mostly implemented in the uninterrupted freeway network with limited spatial system expansion. This paper develops an advanced decentralized traveler information System (ATIS) using vehicle-to-vehicle (V2V) communication system whose performance (drivers' travel time savings) are enhanced by three complementary functions (autonomous automatic incident detection algorithm, reliable sample size function, and driver behavior model) and evaluates it in the typical $6{\times}6$ urban grid network with non-recurrent traffic state (traffic incident) with the varying key parameters (traffic flow, communication radio range, and penetration ratio), employing the off-the-shelf microscopic simulation model (VISSIM) under the ideal vehicle communication environment. Simulation outputs indicate that as the three key parameters are increased more participating vehicles are involved for traffic data propagation in the less communication groups at the faster data dissemination speed. Also, participating vehicles saved their travel time by dynamically updating the up-to-date traffic states and searching for the new route. Focusing on the travel time difference of (instant) re-routing vehicles, lower traffic flow cases saved more time than higher traffic flow ones. This is because a relatively small number of vehicles in 300vph case re-route during the most system-efficient time period (the early time of the traffic incident) but more vehicles in 514vph case re-route during less system-efficient time period, even after the incident is resolved. Also, normally re-routings on the network-entering links saved more travel time than any other places inside the network except the case where the direct effect of traffic incident triggers vehicle re-routings during the effective incident time period and the location and direction of the incident link determines the spatial distribution of re-routing vehicles.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.4
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• pp.291-298
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• 2007

Purpose: To investigate the feasibility of TI-201 SPECT with intra coronary injection (lC-I) in the detection of viable myocardium, we have performed SPECT imaging after direct intracoronary injection of TI-201 and images were compared with those of stress-reinjection (Re-I) SPECT. Methods: Fourteen coronary artery disease patients (male 11, mean age 54 years) who had myocardial infarction or demonstrated left ventricular wall motion abnormality on echocardiography were enrolled. Three mCi of TI-201 was injected into both coronary arteries during angiography and images were acquired between 6- and 24-hour after injection. Reinjection imaging with 1 mCi of TI-201 was performed at 4-hour after adenosine stress imaging with 3 mCi of TI-201. Images were interpreted according to 4-grade visual scoring system (grade 0-3). Segments with mild to moderated uptake (${\leq}$grade 1), and upgraded more than one score with reinjection, and were defined as viable myocardium. Results: Image quality was poor in two cases with IC-I. Numbers of non-viable segments were 60 (23.8%) with IC-I, and 38 (15.1%) with Re-I, respectively. Overall agreement for perfusion grade per myocardial segment in each IC-I and Re-I was 76.5%. Overall agreement for viable segment between IC-I and Re-I was 90.5%. Only one out of 38 segments interpreted as non-viable with Re-I were interpretated as viable with IC-I. And 23 out of 214 segments interpreted as viable with Re-I were interpreted as non-viable with IC-I. Conclusion: Intracoronary TI-201 SPECT seemed to be not advantageous over stress-rest reinjection imaging in the assessment of myocardial viability, mainly due to low count statistics at 6-hour or 24-hour delayed time points. The feasibility of intracoronary TI- 201 SPECT is considered to be limited.

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.57-67
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• 1975

The poxvirus group is considered to be a typical cytoplasmic inclusion forming virus. Every poxvirus has been reported to produce only one kind of inclusion in the infected tissues. A vague concept that inclusions of poxviruses are eosinophilic or acidophilic has prevailed. Although many papers and theories about the nature of the inclusion have been presented, most of them are not quite convincing on the point of the relations with virus multiplication, and an analysis of papers published showed that there seem to be many discrepancies in the descriptions of the nature of the poxvirus inclusions. Comparative studies on host-virus interaction with cowpox, orf, swinepox and fowlpox viruses which selected from each Group (I-IV) of poxviruses were performed from the morphological and virological standpoints. At first, in cowpox virus-FL cell system, as a comparative model, cytoplasmic inclusion, nucleic acid metabolism by autoradiography and detection of viral antigen by immunofluorescence were studied and obtained the results as follows: 1. The focus-like cytopathic effect (CPE) at early stage developed to entire culture at terminal stage of infection, and also the developing status of CPE was correlated to viral doses for inoculation. Two kinds of cytoplasmic inclusions which named A and B type were easily observed by Giemsa, hematoxylin-eosin (H & E) and May-Greenwald Giemsa (MGG) stainings in the infected cells. The B type inclusions were formed at early stage of infection and the A type inclusions were produced subsequently the B type formation. The B type which common type inclusion in poxviruses was a small compact or aggregate at early stage and developed to a large diffuse body at terminal stage of infection. On the other hand, the A type inclusion which depend upon the kind of virus was appeared as round and discrete shape, and its size and number was increased gradually during the culture period. It was characteristic to form distinct halos around the both types of inclusions in acid fixed, H & E stained preparations of infected cultures. The B type inclusion was always positive in Feulgen reaction and showed as DNA containing body but the A type inclusion was not. 2. In the relationship between inclusion and DNA metabolism of infected cells by the qualitative autoradiography using 3H-thymidine, the appearance of silver grains was coincided with B type inclusion but not with A type inclusion. This showed that the DNA synthesis was proceeded in all B type inclusions except those in the terminal stage with a diffuse form. This suggested that the B type inclusions are only sites of DNA synthesis and this was proceeded after the cell infection independently. The activity of DNA synthesis of the inclusions was nearly the same as that of the nucleic of normal cells and non-inclusion bearing cells. and non-inclusion bearing cells. Regardless of the size of the degree of DNA synthesis of the B type inclusion, inclusion bearing cells all showed remarkable suppression of nuclear DNA synthesis. 3. By the direct fluorescent antibody technique viral antigen in infected cells was detected. The B type inclusions have been proved to contain a great deal of viral antigen, whereas the basic substance of A type inclusion did not show antigenicity except the round edge. It was suggested that the round edge fluorescence might be caused by the glare of cytoplasmic viral antigen which pushed out and concentrated by the A type inclusion development. 4. Hemorrhagic red pock formations on chorioallantoic membrane of embryonated chicken egg had proved the characteristic of used viral strain. 5. By the above studies on the nature of two types of inclusions and the role they play in virus multiplication, it was concluded that the B type inclusion must be the site of the synthesis of viral DNA and protein as well as the site of the virus.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.85-90
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• 2017

The $TiCl_4$ as a blocking material is adsorbed in the mesoporous $TiO_2$ electron transfer layer(ETL) of the Perovskite solar cell to prevent the direct contact between the FTO electrode and the photoactive layer(AL), and facilitate the movement of the electrons between $TiO_2:TiCl_4$ ETL and Perovskite AL to improve the photoelectric conversion efficiency(PCE). The structure of the perovskite solar cell is FTO/$TiO_2:TiCl_4$/Perovskite($CH_3NH_3PbI_3$)/spiro-OMeTAD/Ag. It was investigated that the dipping time of the $TiO_2$ into $TiCl_4$ aqueous solution affects on the photoelectric characteristics of the device. By the dipping for 30 minutes, the PCE of the perovskite solar cell with the $TiO_2:TiCl_4$ ETL was the highest 10.46%, which is 27% higher than the cell with $TiO_2$ ETL. From SEM, EDS, and XRD characterization on the $TiO_2:TiCl_4$ ETL and the perovskite AL, it was measured that the decrease of the porosity of the $TiO_2$ layer, the detection of the Cl component by the $TiCl_4$ adsorption, the cube-type morphology of perovskite AL, and shift of the $PbI_2$ peak of the perovskite AL. From these results, it was confirmed that the $TiO_2:TiCl_4$ ETL and the perovskite AL were formed.