• IMMUNE NETWORK
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• v.1 no.3
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• pp.250-259
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• 2001

To determine if initial infection with Mycobacterium tuberculosis changes the balance of cytokines between T cells and macrophages, we evaluated interferon (IFN)-${\gamma}$), interleukin-12 (IL)-12, and tumor necrosis factor (TNF)-${\alpha}$ productions by peripheral blood mononuclear cells (PBMC) from 15 untreated active pulmonary tuberculosis (TB) patients and 12 healthy tuberculin reactors (HTR). Freshly isolated PBMC were stimulated with Triton X-100 solubilized protein (TSP), 30-kDa or purified protein derivatives (PPD) antigen for 6, 18 and 96 hours. IL-12 p40 production by antigen-stimulated PBMC from TB patients was significantly decreased compared with that in HTR. In addition, IFN-${\gamma}$ production was significantly depressed in TB patients than that in HTR at a 96-hr stimulation. However, TNF-${\alpha}$ production was significantly higher in antigen-stimulated PBMC from TB than that of HTR. A pronounced increase in IFN-${\gamma}$ protein followed neutralization of IL-10 in early TB patients. However, neutralization of TNF-${\alpha}$ did not significantly alter IFN-${\gamma}$ induction in PBMC from TB patients. There were no significantly differences in the cytokine productions among three proteins, TSP, 30-kDa or PPD antigen. These results indicate that development of TB may be strongly associated with dysregulated productions of IL-12, IFN-${\gamma}$ and TNF-${\alpha}$, during the initial immune responses to M. tuberculosis. Further understanding of operative cytokine networks during human immune cell responses to protein antigens of M. tuberculosis may improve strategies for vaccine development.

• The Korean Journal of Nuclear Medicine
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• v.25 no.2
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• pp.245-251
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• 1991

결핵성 병변의 단순 x-ray 촬영이나 CT, MRI 소견은 매우 다양하며, 결핵과 전이암 혹은 원발성 암과 감별이 어려운 경우가 있어 결핵으로 확진하기 위하여서 조직 생검이나 수술 등 침습적인 진단 방법을 이용하여야 하였다. 그러므로 이러한 결핵 병변을 비 침습적인 방법으로 정확히 감별할 수 있는 방법을 연구하던 바, 결핵균에 대한 항체를 동위원소에 부착시켜 신티그래피로 진단할 수 있는지의 가능성을 동물실험을 통하여 알아보고자 하였다. 15마리의 가토에서 M.tuberculosis H37Rv를 슬관절에 주입시켜 결핵병변을 유발시키고, 대조군으로 2마리의 가토의 고환에 T.pallidum을 주입하여 매독병변을 유발시킨 후 M.bovis BCG에 대한 특이항체 (specific polyclonal antibody)와 정상 가토의 immunoglobulin을 I-131에 부착시켜 각각의 가토에 주입하여 preset time 10분간 감마카메라로 주사한 결과 다음과 같은 결과를 얻었다. (1) 8마리의 결핵에 감염된 가토에 M.bovis BCG에 대한 $F(ab')_2$를 1 mCi의 I -131 labeling 시킨후 주사한 결과 모두에서 주사후 2시간 부터 72시간까지 병소가 hot uptake으로 보였으며 주사후 24 시간에 가장 높은 target/background ratio를 보였다. (2) 2마리의 매독에 감염된 가토에서 anti-BCG $F(ab')_2$를 주사한 결과 2시간에서는 병소에 hot activity를 보였으나 24시간부터 급격히 activity가 감소하였다. (3) $F(ab')_2$ 대신에 intact antibody를 결핵에 감염된 가토에 투여한 결과 specific polyclonal antibody나 정상가토의 immunoglobulin 모두 결핵병소에 96시간까지 hot uptake를 보였다. 그러므로 결핵균에 대한 specific antibody fragment를 이용하면 방사면역 신티그램으로 진단이 가능하리라 사료되었고, intact antibody를 사용할 경우 sensitivity는 높으나 specificity는 적을 것으로 사료되었다.

• Pediatric Infection and Vaccine
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• v.21 no.1
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• pp.22-28
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• 2014

Purpose: This study aimed at determining the detection rate of respiratory viruses and at investigating the risk factors associated with respiratory virus detection in young infants. Methods: From September 2011 to August 2012, nasopharyngeal swabs were obtained from 227 infants aged ${\leq}90$ days with suspected infectious diseases, including sepsis. We performed a retrospective analysis of their clinical characteristics. The prevalence of respiratory viruses in their nasopharyngeal swabs was assayed by real-time polymerase chain reaction (real-time PCR). Results: In total, 157 (69.2%) infants had more than one of the following respiratory viruses: respiratory syncytial virus (n=75), rhinovirus (n=42), influenza virus (n=18), parainfluenza virus (n=15), human metapneumovirus (n=9), coronavirus (n=9), adenovirus (n=4), and bocavirus (n=3). During the same period, bacterial infections were confirmed in 24 infants (10.6%). The detection of respiratory viruses was significantly associated with the presence of cough, a family history of respiratory illness, and a seasonal preference (fall/winter). Using logistic regression analysis, these 3 variables were also identified as significant risk factors. During fall and winter, detection of respiratory viruses was significantly higher in infants who did not have a bacterial infection. Conclusion: Respiratory virus is an important pathogen in young infants admitted to a hospital, who are suspected with infectious diseases. Detection of respiratory viruses in young infants was associated with seasonality (fall/winter), presence of respiratory symptoms and a family history of respiratory illness.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.471-482
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• 1996

Early recognition of coalescence in pneumoconiotic lesions is important because such coalescence is associated with the respiratory symptoms and deterioration of lung function. This complicated form of pneumoconiosis also has worse prognosis than does simple pneumoconiosis. High resolution computerized tomography(HRCT) provides significant additional information on the stage of the pneumoconiosis because it easily detects coalescence of nodules and emphysema that may not be apparent on the simple radiograph. The purpose of this study is to clarify the role of HRCT in detection of large opacity and the relationship of change between the coalescence of nodules or emphysema and lung function in dust exposed workers. 1. There was good correlation between the HRCT grade of pneumoconiosis and ILO category of profusion. 5(9.09%) in 55 study population had confluent nodule extending eve, two o, more cuts on HRCT. HRCT could identify the pneumoconiotic nodules which was not found by simple radiogrphy in 6 workers with category 0/0. 2. No significant difference was observed coalescence of nodules and emphysema by dust type. 3. There was no significant difference in pulmonary function according to ILO and HRCT classification. 4. HRCT could detect the significant reduction in $FEV_1,\;FEV_1/FVC$, PEFR, $FEF_{25},\;FEF_{50},\;and\;FEF_{75}$ and remarkable increase in RV and TLC in study persons with emphysema compared with non-emphysema group. 5. Emphysema was found more often in nodules-coalescence group than small opacity group by HRCT. We found that HRCT could easily detect areas of coalescence and complicated emphysema compared to plain chest X-ray. Also our data suggest that it is primarily the degree of emphysema rather than the degree of pneumoconiosis that determines the level of pulmonary function.

• Journal of Chest Surgery
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• v.17 no.4
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• pp.593-606
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• 1984

With the ligation of patent ductus arteriosus by Gross in 1938, surgeons first entered the field of congenital heart disease. Interruption of a ductus is one of the most satisfactory and curative operations in the field of surgery for congenital heart disease. 27 cases of isolated patent ductus arteriosus were operated from Jan. 1978 to July 1984 at the Department of Thoracic & Cardiovascular Surgery in Kyung-Hee University Hospital. Retrospective clinical analysis of these patients were: 1. Sex ratio, female: male, was 2:1. 2. Mean age at operation was 9.85\ulcorner.58 years. The youngest patient was a 23 month-old girl and the oldest one was a 24 year-old male. 3. More than half of the patients had less than 50 percentile of growth retardation. 4. Chief complaints of the patients were frequent URI [52%], dyspnea on exertion [33%], generalized weakness [22%], palpitation [7%], but 7 patients [26%] had no subjective symptoms. 5. Continuous machinery murmur could be heard at the 2nd or 3rd intercostal space on the left sternal border in 22 patients [81%]. The other S patients made systolic murmur with accentuation of the second heart sound and those were associated with pulmonary hypertension. 6. Radiologic findings of Chest P-A were cardiac enlargement in 15 patients [55%], enlargement of pulmonary conus and/or increasing density of pulmonary vascularity in 20 patients [74%]. 7. Electrocardiographic findings of the patients were within normal limit in 13 patients [48%], LVH in 4 patients [15%], biventricular hypertrophy in 3 patients [11%]. 8; echocardiogram was obtained from 11 patients. Ductus was directly visualized in 7 patients. Left atrial enlargement is the secondary change of left to right shunt, 10 patients had LA/Ao ratio more than 1.2. 9. Cardiac catheterization performed in 25 patients. The mean value of the results were:SO2[PA-RV]= 14.72\ulcorner6.01%, Qp/Qs=2.22\ulcorner.80, peak systolic pulmonary arterial pressure=48.28\ulcorner1.60 mmHg. 10. 26 patients were operated through the left posterolateral thoracotomy: closure of ductus by double ligation in 14 cases, triple ligation in 5 cases, and division with suture in 8 cases. One patient suffer from aneurysmal rupture of main pulmonary artery, endocarditis, hemopericardium was treated with cardiopulmonary bypass via median sternotomy and closure of ductus through the ruptured main pulmonary artery. 11.There was no death associated with the operation, but 3 cases were experienced with intraoperative rupture around the ductus resulting in massive bleeding. The other complications were transient hoarseness in one patient, atelectasis in left lower lobe in 3 patients, and postoperative systemic hypertension in 4 patients with unknown etiology. 12. Pulse pressure was reduced, 11.47+5.92 mmHg, postoperatively, as compare to preoperative status. 13. Intraoperative wedge lung biopsy from lingular segment for the evaluation of the pulmonary vascular disease was taken in S patients with severe pulmonary hypertension. The result was Heath-Edward grade I in one case, grade II in two cases, and grade III in two cases.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2001.11a
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• pp.7-7
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• 2001

The increasing interest in light weight materials coupled to the need for cost -effective processing have combined to create a significant opportunity for aluminum P/M. particularly in the automotive industry in order to reduce fuel emissions and improve fuel economy at affordable prices. Additional potential markets for Al PIM parts include hand tools. Where moving parts against gravity represents a challenge; and office machinery, where reciprocating forces are important. Aluminum PIM adds light weight, high compressibility. low sintering temperatures. easy machinability and good corrosion resistance to all advantages of conventional iron bm;ed P/rv1. Current commercial alloys are pre-mixed of either the AI-Si-Mg or AL-Cu-Mg-Si type and contain 1.5% ethylene bis-stearamide as an internal lubricant. The powder is compacted in closed dies at pressure of 200-500Mpa and sintered in nitrogen at temperatures between $580~630^{\circ}C$ in continuous muffle furnace. For some applications no further processing is required. although most applications require one or more secondary operations such as sizing and finishing. These sccondary operations improve the dimension. properties or appearance of the finished part. Aluminum is often considered difficult to sinter because of the presence of a stable surface oxide film. Removal of the oxide in iron and copper based is usually achieved through the use of reducing atmospheres. such as hydrogen or dissociated ammonia. In aluminum. this occurs in the solid st,lte through the partial reduction of the aluminum by magncsium to form spinel. This exposcs the underlying metal and facilitates sintering. It has recently been shown that < 0.2% Mg is all that is required. It is noteworthy that most aluminum pre-mixes contain at least 0.5% Mg. The sintering of aluminum alloys can be further enhanced by selective microalloying. Just 100ppm pf tin chnnges the liquid phase sintering kinetics of the 2xxx alloys to produce a tensile strength of 375Mpa. an increilse of nearly 20% over the unmodified alloy. The ductility is unnffected. A similar but different effect occurs by the addition of 100 ppm of Pb to 7xxx alloys. The lend changes the wetting characteristics of the sintering liquid which serves to increase the tensile strength to 440 Mpa. a 40% increase over unmodified aIloys. Current research is predominantly aimed at the development of metal matrix composites. which have a high specific modulus. good wear resistance and a tailorable coefficient of thermal expnnsion. By controlling particle clustering and by engineering the ceramic/matrix interface in order to enhance sintering. very attractive properties can be achicved in the ns-sintered state. I\t an ils-sintered density ilpproaching 99%. these new experimental alloys hnve a modulus of 130 Gpa and an ultimate tensile strength of 212 Mpa in the T4 temper. In contest. unreinforcecl aluminum has a modulus of just 70 Gpa.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.51-62
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• 2007

Recently, the pavement distresses in the bridge deck have seriously affected the durability of bridge deck and driver's safety. The existing asphalt materials have the limitations in reducing the pavement distresses of brides deck. To protect the bridge deck and withstand the high deflection, it is necessary to develop the asphalt materials with good fatigue resistance for bridge deck pavement. The asphalt binder combined with SBS and two other admixtures has been developed for improving the resistance to fatigue cracking, productivity, and workability for bridge deck pavement. Based on the various binder test results, the developed binder is found to be PG 70-34 indicating very higher resistance against fatigue cracking. Fatigue testing, wheel tracking testing, and moisture susceptibility testing have been conducted to evaluate the performance of asphalt mixtures developed in this study. Laboratory test results show that the developed asphalt material has three times higher fatigue lives than the typical modified asphalt mixture. Full scale accelerated testing was also performed on the typical asphalt mixture and newly developed asphalt mixture to evaluate the full scale performance of asphalt mixtures. Test results indicate that the length of cracking on the new materials is only 38% of the typical material at the 250,000 load repetitions.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.237-246
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• 2005

Background: Little information is available on the identification and characterization of the upstream regulators of the signal transduction cascades for Mycobacterium tuberculosis (M. tbc)-induced ERK 1/2 activation and chemokine expression. We investigated the signaling mechanisms involved in expression of CCL3 /MIP-1 and CCL4/MIP-1 in human primary monocytes infected with M. tbc. Methods: MAP kinase phosphorylation was determined using western blot analysis with specific primary antibodies (ERK 1/2, and phospho-ERK1/2), and the upstream signaling pathways were further investigated using specific inhibitors. Results: An avirulent strain, M. tbc H37Ra, induced greater and more sustained ERK 1/2 phosphorylation, and higher CCL3 and CCL4 production, than did M. tbc H37Rv. Specific inhibitors for mitogen-activated protein kinase (MAPK) kinase (MEK; U0126 and PD98059) significantly inhibited the expression of CCL3 and CCL4 in human monocytes. Mycobactetia-mediated expression of CCL3 and CCL4 was not inhibited by the Ras inhibitor manumycin A or the Raf-1 inhibitor GW 5074. On the other hand, phospholipase C (PLC) inhibitor (U73122) and protein kinase C (PKC)specific inhibitors ($G\ddot{o}6976$ and Ro31-8220) significantly reduced M. tbc-induced activation of ERK 1/2 and chemokine synthesis. Conclusion: These results are the first to demonstrate that the PLC-PKC-MEK-ERK, not the Ras-Raf-MEK-ERK, pathway is the major signaling pathway inducing M. tbc-mediated CCL3 and CCL4 expression in human primary monocytes.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.8-13
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• 1996

Background: The 463 codon mutation of katG gene has been reported as an useful marker for the detection of isoniazid(INH) resistant strains of M. tuberculosis. This study aimed to elucidate relationship between 463 mutation in katG gene and INH resistance in M. tuberculosis. Method: DNA was extracted from 28 INH susceptible strains(MIC$\geq\;0.2{\mu}g/ml$ on the L$\ddot{o}$wenstein Jensen media) and used for amplification of 189bp fragment containing 463 codon by PCR. Amplified fragments were digested by restriction enzyme Msp I, analyzed by single strand conformation polymorphism(SSCP) in the MDE gel and sequenced to prove mutation. Result: Only 7(25%) out of 28 were digestible by restriction enzyme Msp I. The SSCP pattern of 21 strains were distinctly different from that of M. tuberculosis H37Rv. Msp I undigestible PCR fragment was substituted at 463 codon from Arg(CGG) to Leu(CTG). Conclusion: This finding clearly indicate no relationship between 463 codon mutation of the katG gene and INH resistance.

• Tuberculosis and Respiratory Diseases
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• v.57 no.2
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• pp.125-131
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• 2004

Tuberculosis (TB) remains an enormous global health problem, and a new vaccine against TB more potent than the current inadequate BCG vaccine is urgently needed. We constructed three recombinant Mycobacterium bovis BCG (rBCG) strains over-expressing antigen (Ag) 85A, Ag85B, or both of M. tuberculosis using their own promoter and secretory sequence, or hsp60 promoter. SDS-PAGE analysis of rBCG proteins showed overexpression of Ag85A and Ag85B proteins in higher level than of those in their parental strain of BCG. In addition, rBCG(rBCG/B.FA) over-expressing Ag85A and Ag85B induced strong IFN-${\gamma}$ production in splenocytes. However, there was no significant difference in protective efficacy between rBCG and their parental BCG strain. In this study, therefore, rBCG over-expressing Ag85A, Ag85B, or both failed to show enhanced protection against M. tuberculosis infection in a mouse model.