• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.497-507
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• 2000

Purpose: We have examined the utility of $^{99m}Tc$-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. Materials and Methods: Our study included 80 renal transplant recipients (48 men and 32 women, mean age: 40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of $^{99m}Tc$-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. Results: The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN wore significantly greater than that of NG. WK-Tmax of AR was significantly longer than that of NG. K20/3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. Conclusion: TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups.

• Pediatric Infection and Vaccine
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• v.9 no.2
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• pp.182-192
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• 2002

Purpose : This study was performed to characterize the epidemiologic and clinical features of acute adenoviral lower respiratory tract infections(LRTIs). Methods : Virological analysis was done from respiratory specimens obtained from patients with LRTIs hospitalized to other hospitals and referred to the Department of Pediatrics, Seoul National University Children's Hospital(SNUCH) from June 1998 to July 2000. Viral diagnosis was made by isolation of viruses employing HEp-2 cell culture and indirect immunofluorescent staining with monoclonal antibodies. Serotypes of adenoviruses were determined by neutralization test using antiserum for types 1, 2, 3, 4, 5, 6, 7 and 11. Medical records of children admitted to the SNUCH were reviewed retrospectively. Results : Adenovirus was isolated from 118(9.0%) of 1,305 children with LRTIs. Serotypes were 3(39.0%), 7(16.9%), 1(11.0%), 2(7.6%), 4(7.6%), 6(5.9%), 11(2.5%), and 5(0.8%) and 10 strains(8.5%) were not neutralized by antisera included in the study. Infections by type 3 and type 7 occurred in outbreaks. Male to female ratio was 1.0:0.9 and mean age was 1.95 years. The clinical diagnoses were pneumonia(83%), acute tracheobronchitis(12%) and bronchiolitis(5%). Associated symptoms, signs and abnormal laboratory findings included cough(100%), sputum(73.5%), fever(54.2%), rale(59.3%), wheezing(34%), anemia(35%) and leukopenia(15.8%). Mortality was in 13.5%. Residual radiologic sequelae was identified in 32.6% of the patients followed. Conclusion : These data confirms that adenovirus may cause severe lower respiratory tract diseases, and infections by type 3 and 7 may occured in outbreaks.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.102-108
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• 2012

Purpose: We investigated the clinical presentation of febrile pediatric patients with acute pyelonephritis (APN) with a mixed urine culture from an aseptic urine sample, and compared with that of those with a single culture. Methods: We retrospectively reviewed the medical charts of 95 patients diagnosed as APN with fever between January 2008 and October 2010 at Korea University Medical Center. We classified the patients with APN into two groups with a positive single culture (S group) and a positive mixed culture (M group) from an aseptic urine sample of suprapubic bladder aspiration or urethral catheterization and compared the fever duration, laboratory markers such as serum white blood cell (WBC) counts and C-reactive protein (CRP) values in peripheral blood, and the presence of hydronephrosis, renal scar and vesicoureteral reflux (VUR) between the two groups (If presence of hydronephrosis, scar and VUR=1 and no=0). Results: Total pediatric patients with febrile APN were 95 patients, a positive S group was 89 patients and a positive M group was 6 patients. Fever duration (S vs. M, $4.7{\pm}3.1$ vs. $6{\pm}5.7$ days), serum WBC (S vs. M, $18,630{\pm}6,483$ vs. $20,153{\pm}7,660/{\mu}L$) and CRP (S vs. M, $100.6{\pm}2.46$ vs. $81.1{\pm}0.09\;mg/L$) values, and the presence of hydronephrosis, renal scar and VUR were not different between the two groups. Conclusion: Our data shows that there were no specific differences of clinical manifestation between a positive single urine culture and a positive mixed urine culture in pediatric APN. A mixed urine culture from an aseptic urine sample should be interpreted cautiously.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.89-94
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• 2012

Purpose: The option of selecting isotonic rather than hypotonic fluids for maintenance fluid in children has been advocated by some authors. Pneumonia and CNS infections are frequent clinical settings for acute hyponatremia because of nonosmotic anti-diuretic hormone stimuli in children. We conducted the present study to identify the incidence of hyponatremia in pneumonia and CNS infection of children and to determine the importance of maintenance intravenous fluid therapy regimen and other related factors. Methods: The study included 1,992 patients admitted to the Department of Pediatrics at Pusan National University Children's Hospital between November 2008 and August 2011, who were diagnosed with pneumonia or CNS infections and checked for serum sodium concentration. Their clinical data including laboratory findings were reviewed retrospectively. Results: During the study period, 218 patients were identified to have acute hyponatremia among 1,992 patients. The overall incidence of hyponatremia was 10.9%. The incidence of hyponatremia in encephalitis (37.3%) was highest and the incidence in bacterial meningitis (27.4%), viral meningitis (20.0%), bacterial pneumonia (11.1%), mycoplasma pneumonia (9.2%), and viral pneumonia (6.8%) were in descending order. The mean age was higher in hyponatremic patients than in isonatremic patients. The incidence of hyponatremia was higher in who had 0.18% NaCl in 5% dextrose (D5 0.18% NS) than 0.45% NaCl in 5% dextrose infusion (D5 1/2NS) (9.0% vs. 2.2%). SIADH was identified in 20.5% among hospital acquired hyponatremic patients after adequate evaluation for SIADH. Conclusion: We recommend D5 1/2NS rather than D5 0.18% NS as the maintenance fluid given to children with pneumonia or infectious CNS diseases.

• Tunnel and Underground Space
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• v.30 no.4
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• pp.382-393
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• 2020

The engineered barrier system of high-level radioactive waste disposal must maintain its performance in the long term, because it must play a role in slowing the rate of leakage to the surrounding rock mass even if a radionuclide leak occurs from the canister. In particular, it is very important to clarify gas dilation flow phenomenon clearly, that occurs only in a medium containing a large amount of clay material such as a bentonite buffer, which can affect the long-term performance of the bentonite buffer. Accordingly, DECOVALEX-2019 Task A was conducted to identify the hydraulic-mechanical mechanism for the dilation flow, and to develop and verify a new numerical analysis technique for quantitative evaluation of gas migration phenomena. In this study, based on the conventional two-phase flow and mechanical behavior with effective stresses in the porous medium, the hydraulic-mechanical model was developed considering the concept of damage to simulate the formation of micro-cracks and expansion of the medium and the corresponding change in the hydraulic properties. Model verification and validation were conducted through comparison with the results of 1D and 3D gas injection tests. As a result of the numerical analysis, it was possible to model the sudden increase in pore water pressure, stress, gas inflow and outflow rate due to the dilation flow induced by gas pressure, however, the influence of the hydraulic-mechanical interaction was underestimated. Nevertheless, this study can provide a preliminary model for the dilation flow and a basis for developing an advanced model. It is believed that it can be used not only for analyzing data from laboratory and field tests, but also for long-term performance evaluation of the high-level radioactive waste disposal system.

• Toxicological Research
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• v.8 no.2
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• pp.343-357
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• 1992

Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.112-117
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• 1996

Objective: Standard stress/rest Tc-99m MIBI and T1-201 myocardial perfusion study have some limitations such as stress/rest image overlap for Tc-99m-MIBI, low energy for T1-201 and long period of study time for two separate studies. Separate acquisition rest T1-201/stress Tc-99m MIBI dual isotope study is a potentially efficient myocardial perfusion imaging protocol that combines the high resolution of Tc-99m for stress perfusion assessment and T1-201 for viability assessment. This study assessed the usefulness and diagnostic accuracy for this new approach. Methods: We tried to evaluate sensitivity and specificity of dual isotope separate acquisition protocol in 67 patients. Immediately after resting T1-201 SPECT data was acquired, dipyridamole stress Tc-99m MIBI myocardial perfusion study was performed. Visual analysis was carried out qualitatively with 0 to 3 scoring system for 17 segments of left ventricle in the reconstructed horizontal long axis and short axis slices. Results: Total study was completed within 3 hours. In angiographic correlation, dual isotope SPECT demonstrated high sensitivity(85%) and in a small group of patients, high specificity was also observed (100%). Conclusion: Combined thallium-201/stress Tc-99m MIBI SPECT displayed similiar diagnostic accuracy to protocol using stress/rest Tc-99m MIBI SPECT. This protocol was completed in shorter period than the previous protocols and therefore enhance laboratory throughput and patients convenience.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.2
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• pp.162-168
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• 2006

Purpose: Microbial colonization of the intestine begins just after birth and development of the normal flora is a gradual process. The first bacteria colonizing the intestine in newborns are Staphylococcus, Enterobacteriaceae and Streptococcus. For several days after birth, the number of Bifidobacterium spp. increase. The aim of this study was to investigate the changes of microflora for seven days postnatally in neonatal stool. Methods: Fifteen neonates (breast : formula : mixed feeding 1 : 8 : 6, vaginal delivery : cesarean section 3 : 12) who were born at the Kangdong Sacred Heart Hospital, Hallym University were enrolled. First meconium and stools of postnatal 1-, 3-, and 7-day were innoculated. Blood agar plates for total aerobes, trypton bile X-glucuronide agar for E. coli, phenylethyl alcohol agar for gram positive anaerobes, MRS agar for Lactobacillus spp., bifidobacterium selective agar for Bifidobacterium spp. and cefoxitin-cycloserine-fructose agar for Clostridium difficile were used in the general incubator ($CO_2$ free incubator), $CO_2$ incubator or the anaerobic chamber for 48 or 72 hours at $37^{\circ}C$ and then colony forming units were counted. Results: No microflora was identified in the first meconium. Total aerobes, E. coli, and gram positive anaerobes were significantly increased with advancing postnatal days. In only one baby, Lactobacillus acidophilus was detected $2{\times}10^5CFU/g$ in the seven-day stool. Bifidobacterium spp. was detected in two babies. Clostridium difficile was not detected during the seven days. There were no significant differences in the bowel flora depending on the delivery pattern and feeding method. Conclusion: This study shows many changes in the intestinal normal flora in neonatal stool during seven days postnatally. If these findings are confirmed with larger studies, the data may be preliminary findings to support use of probiotics in neonates.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.186-192
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• 2007

This study was conducted to survey the hygienic status of chicken meats on the microbial levels, which were collected from poultry processing plants located in the local provinces in nationwide including the JeJu island (n=15) in 1997. In particular, Salmonella spp., Campylobacter jejuni, and Listeria monocytogenes, which were retarded as one of the most important entero-pathogens relating to food home illness from poultry, were investigated on their isolation frequency including the other pathogens related on the food-borne illness. A total of 115 processed chickens were submitted on the present study. In general, the bacterial contamination frequency showed more or less lower $(10{\sim}100 cells)$ than those of sold on the retail and super markets and department stores because of lacking of cross-contamination incidences, depending on the total cells, Coliforms and Staphylococcal cells count. While, Salmonella species, Campylobacter jejuni, Listeria monocytogenes, and coagulase positive Staphylococcus aureus isolation frequency of chicken meats from slaughter houses were 58.3%, 37.4%, 43.5%, and 30.4%, in order. But the present microbial isolation data were a little lower levels than those of sold on the retail and super markets and famous department stores in Seoul and GyeongGi province at the same period. It seemed that the cross-contamination problems (including the human, environmental and instrumental factors) during the marketing stage (after the last processing procedure; rinsing step) had the major roles on the increasing of the microbial contamination frequency on the chicken meats after the slaughter houses.

• Journal of Hospice and Palliative Care
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• v.5 no.1
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• pp.24-30
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• 2002

Background : Pain is one of the most feared consequences of cancer. $65{\sim}85%$ of cancer patients experienced severe pain, and sometimes high dose morphine is used to these patients. But many doctors still have 'opioid-phobia' and hesitate to use high dose morphine. We investigated the morphine therapy in terminal cancer patients during the last 1 week to death, and found any differences according to the morphine dosage. Methods : 93 patients admitted to National Health Insurance Corporation Ilsan Hospital, department of family medicine for hospice care between September 2000 and the end of October 2001 and lived more than 1 week entered in the study. We investigated the demographic data, laboratory tests and sufficient dosage of morphine for pain control. According to the calculated dosage by OME(oral morphine equivalent), patients were divided into low dosage group (${\leq}150mg/day$) and high dosage group (>150 mg/day). The chi-squared test were used to evaluate the influence of age, gender, tumor sites, metastasis and adverse effects of morphine. Results : Mean age was $65.0{\pm}13.1year$ in low dosage group and $59.9{\pm}11.6year$ in high dosage group. 32 men (50.0%) and 32 women (50.0%) were included in low dosage group and 15 men (51.7%) and 14 women (48.3%) in high dosage group. Stomach was the most frequent tumor site and lung was the next. Metastasis were found 58 (90.6%) in low dosage group and 28 (96.6%) in high dosage group. In other palliative radiotherapy and adverse effects, there were no differences in both group. Conclusion : During the last 1 week to death in cancer patients, there were no difference according to the morphine dosage. So we don't have to have 'opioid-phobia' in treating the terminal cancer patients.