• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.143-153
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• 2003

Purpose : Infection with Shiga-like toxin (SLT)-producing Escherichia coli, an emerging human pathogen found particularly in young children under 5 years of age, causes a spectrum of illnesses with high morbidity and mortality, ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome. Host mediators play an important role in the pathogenesis of SLT-I toxicity. The experiments described here were designed to investigate the effect of SLT-I on TNF-${\alpha}$ production and to understand the effect of TNF-${\alpha}$ on GB3 expression. We also further examine the relationship between the Gb3 level and the differential susceptibility of cells to the cytotoxic action of SLT-I. Methods : The effect of purified SLT-1 from E. coli O157 : H7 (ATCC 43890) on tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) production in Raw264.7 cells was investigated. Many mediators regulate endothelial cell membrane expression of the glycolipid globotriaosyleramide (Gb3), which serves as the toxin receptor, suggesting that the host response to the toxin or other bacterial products may contribute to pathogenesis by regulating target cell sensitivity to the toxins. Therefore, the relationships between Gb3 expression and cytotoxicity against SLT-I on three types of cells were evaluated. Results : Detectable levels of TNF-${\alpha}$ were produced as early as six hours after induction and continued to increase during 48 hours by SLT-I. It was also found that Vero cells and dendritic cells (DC2.4 cells) expressed high levels of Gb3, 83% and 68%, respectively, and that Raw264.7 cells had a low level of Gb3 (29%) and appeared refractory to cytotoxicity against SLT-I. Vero cells and DC2.4 cells expressing high levels of Gb3 were highly susceptible to SLT-I. Furthermore, macrophages showed a resistance to SLT-I cytotoxicity, despite the fact that Gb3 expression was enhanced. Conclusion : These results strongly suggest that the expression of Gb3 is necessary but not sufficient to confer sensitivity of macrophages to SLT-I and further underpin the important role of SLT-I and its Gb3 receptors in the pathogenesis of E. coli O157 infection.

• Childhood Kidney Diseases
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• v.5 no.2
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• pp.78-86
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• 2001

Purpose: Rapidly progressive glomerulonephritis (RPGN) is characterized by the rapid increase in serum creatitnin and crescents formation involving more than $50\%$ of glomeruli. 10 patients who had been treated for RPGN were studied retrospectively for thier underlying diseases and clinical features Method: Cilinical review was performed on 10 children who were diagnosed with RPGN by clinical features and renal biopsy and followed up at department of pediatrics during tile last 10 years, from May 1990 to May 2000. Result: There were 6 males and 4 females between the ages of 2.1 and 14.3 years (mean $10.9{\pm}3.8$). 3 had Henoch-$Sch{\ddot{o}}nlein$ purpura nephritis; 2, idiopathic rapidly progressive glomerulonephritis; 2, lupus nephritis; 1, hemolytic uremic syndrome; 1, membranous glomerulonephritis and 1, microscopic polyangiitis. The most common chief complaints were gross hematuria and oliguria. Initial clinical features included proteinuria, edema, hypertension, nausea and arthralgia. Mean serum BUN was $74.2{\pm}39.1\;mg/dL$ mean serum creatinin, $3.2{\pm}1.8\;mg/dL$ and mean creatinin clearance, $26.5{\pm}13.2\;mL/min/1.73m^2$. Antineutrophil cytoplasmic antibody was positive only in microscopic polyangiitis. ANA and Anti-DNA antibody were positive in two lupus nephritis patients. Serum complements were decreased in 4 patients. All patients except Hemolytic uremic syndrome received steroid pulse therapy and immunosupressive agents. 3 patients were performed acute peritoneal dialysis and 2 patients were given plasmapheresis. At the last follow up, 1 patient was dead, 4 patients had elevated serum creatinin, 2 of these 4 patients were on chronic ambulatory peritoneal dialysis and 6 patients had normal renal function. Conclusion: Rapidly progressive glomerulonephritis is a medical emergency that requires very rapid diagnosis, classification, and therapy. Appropriate therapy selected on the basis of underlying disease mechanism can substantially improve renal survival. (J. Korean Soc Pediatr Nephrol 2001 ; 5 : 78-86)

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.126-131
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• 2015

Pathogenic Escherichia coli is recognized as an important cause of diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome worldwide. This study was conducted to investigate the prevalence E. coli contamination in the Korean traditional food bibimbap. E. coli were isolated from 84 of 1142 (7.3%) bibimbap investigated from 2005 to 2011. Antibiotic resistance profiling demonstrated that 6 of the 84 isolates (7.2%) showed multiple drug resistance. Fifteen virulence genes specific for pathogenic E. coli such as Shiga toxin-producing E. coli (STEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and enteroaggregative E. coli (EAEC) were examined by multiplex PCR for mixed bacterial cultures derived from bibimbap samples. The EPEC virulence gene (ent) was detected in 5 strains (5.9%), while ETEC, EAEC, and EIEC were not detected. STEC serotypes O103 (1.2%), O91 (1.2%), and O128 (6.0%) were found, but other serogroups such as O26, O157, O145, O111 and O121 were not detecded. Automated Repetitive-Sequence-Based PCR analysis showed different patterns.

• Pediatric Infection and Vaccine
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• v.4 no.1
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• pp.73-78
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• 1997

Purpose : Escherichia coli O157 can produce diarrhea as well as hemorrhagic colitis and hemolytic uremic syndrome. In many parts of North America, E. coli O157 often is the second or third most commonly isolated enteric bacterial pathogens. Recently, intakes of fast food, including hamburgers have increased in Korea. Therefore, E. coli O157 infection in Korea are likely to be increased. Methods : Stool samples from 317 pediatric diarrheal patients were analyzed by culture on sorbitol-MacConkey agar. Sorbitol-negative colonies were teated by E. coli O157 latex agglutination test. Results : Of the 317 specimens, one (0.3%) were E. coli O157:NM that not produced Shiga toxin. The 7 year old male patient who had complained of abdominal pain, vomiting and non-bloody diarrhea for 2 days. The patient was improved for 2 days after admission. Conclusions 1 Only one (0.3%) of all fecal samples were isolated E. coli O157 that not produced Shiga toxin. Therefore, routine stool culture for the isolation of E. coli O157 was not likely to be neccessary so far.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.876-884
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• 1997

Fourteen patients underwent orthotopic heart transplantation between March 1994 and May 1996 in Seoul National University Hospital. There were 9 male and 5 female patients, and the mean age was 40.8 $\pm$ 12.4 years ranged from 12 to 56 years. All patient were in NYHA Fc III or IV preoperatively. The underlying heart diseases were dilated cardiomyopathy in 11 and restrictive cardiomyopathy in 3. The mean age of donors was 24.9$\pm$ 10.2 years and the causes of the brain death were head trauma by traffic accidents in 8, subarachnoid hemorrhage in 2, 1 asphyxia, 1 fall down injury, 1 brain tumo , and 1 drowning, respectively The blood type was identical in 11, compatible in 2, and incompatible in 1 patient. The direct bicaval anastomosis technique was used in 11 cases, and standard right atrial anastomosis was done in the remaining 3 cases. The graft ischemic time was 158$\pm$44 minutes ranged 94 to 220 minutes. There were two hospital deaths(14.3%). The causes of deaths were 1 right ventricular failure followed by suspected cyclosporine induced hemolytic uremic syndrome and rejection, and 1 delayed massive bleeding, probably from rupture of the anastomotic pseudoaneurysm, respectively. The follow-up duration was 16$\pm$9 months(3 to 28 months). There was one late death(8.3%). All the other patients were in NYHA Fc I except one patient who was in hospital because of the acute rejection. The actuarial survival rates including hospital deaths were 93.7% at 1 month, 86.9% at 6 months, and 77$\pm$12% at 2 years. Conclusively, heart transplantation is the good strategy for the management of end stage heart disease with acceptable operative mortality and early follow-up results.

• Childhood Kidney Diseases
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• v.10 no.2
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• pp.109-118
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• 2006

Purpose : HUS usually occurs in children after infection with shiga toxin-producing microorganism(D＋HUS). In contrast, non-postdiarrheal(D-) HUS occurs at any age and has a high rate of relapse and a poor prognosis. The clinical presentation of D-HUS is similar to that of thrombotic thrombocytopenic purpura(TTP). Recently severe deficiencies of ADAMTS13 were reported not only in TTP and D- HUS but also in D+ HUS during their acute phase. The purpose of the study is to evaluate the plasma ADAMTS13 activity in D＋ and D-HUS. Methods : Nineteen children with HUS(D＋ HUS 12 and D- HUS 7) were enrolled. The assays of plasma ADAMTS13 activity were performed during the acute stage in the D＋ HUS and at various stages of relapsing courses in the D- HUS patients by multimer assay, based on electrophoresis. Results : The median plasma activity of ADAMTS13 in D＋ HUS and D- HUS were 80.9%(37.8-132.4%) and 53.9%(1.0-94.1%), respectively, which were not statistically significantly different from control(86.4%, 34.2-112.3%)(P>0.05). One boy with D- HUS had severe deficiency of ADAMTS13(1.0%). His platelet count was normalized temporarily by fresh frozen plasma infusion. Conclusion : We have demonstrated that there is no significant difference of the plasma ADAMTS13 activity between D＋ HUS, D- HUS and control. We detected severe deficiency of ADAMTS13 in one boy who presented with relapsing episodes of D- HUS. ADAMTS13 deficiency should be considered in the subgroup of D- HUS especially with early onset and recurrent courses. Plasma therapy can be beneficial in this subgroup.

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.129-134
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• 2017

Diarrheagenic Escherichia coli is now recognized as an important cause of diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome (HUS) worldwide. E. coli were isolated from 80 of 356 (22.5%) chicken and chilled chicken products in Korea. Fifteen virulence genes specific for pathogenic E. coli, including Shiga toxin-producing E. coli (STEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC) and enteroaggregative E. coli (EAEC), were examined by multiplex PCR. STEC virulence markers were detected for eaeA (20.0%), escV (21.3%), stx1 (3.8%), ent (2.5%), EHEC-hly (1.3%), stx2 (1.3%), EAEC virulence marker (astA) was detected in 32.5%. ETEC and EIEC were not detected. STEC serotypes O152, O1, O116, O26, O25, O119 and O153 were found in chicken samples. This suggests the importance of diarrheagenic Escherichia coli control in raw chicken and chilled chicken food for food safety.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.179-184
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• 2010

Escherichia coli O157:H7 is a food-borne pathogen that causes bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). We compared three selective media and evaluated the performance of immunomagnetic separation (IMS) for the detection of low levels of E. coli O157:H7 in ground beef and radish sprouts with different levels of background flora. Bulk food samples (500 g for each trial) were artificially inoculated with nalidixic acid-resistant E. coli O157:H7 at the lowest dose that would generate 20 partial-positive samples of 25 g each. All samples were homogenized in mTSB (225 mL) and incubated overnight at $37^{\circ}C$. IMS was performed using the enriched mTSB samples (1 mL) along with conventional spreads plated onto three different selective media: Sorbitol MacConkey agar (SMAC), Sorbitol MacConkey agar with cefixime and tellulite (CT-SMAC), and Sorbitol MacConkey agar with nalidixic acid (NAL-SMAC) as the gold standard. Two suspicious colonies from each medium were selected and confirmed usinga serological test after transfer to tryptic soy broth with yeast extract (TSAYE). CT-SMAC was better than SMAC for detecting E. coli O157:H7 in all food types. Although there was no statistical difference in the number of positive samples when using IMS vs. non-IMS techniques, more positive samples were detected when IMS was used in both ground beef and radish sprouts. It appears that the improvement was more significant in radish sprouts, which had a higher level of background flora than ground beef. The results also suggest that the combination of CT-SMAC and IMS is sufficient to recover low levels of E. coli O157:H7 in high background flora food samples.

• Childhood Kidney Diseases
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• v.1 no.1
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• pp.4-12
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• 1997

Purpose: To evaluate the prevalence and clinical manifestations of various glomerulonephritis (GN) in children, a clinicopathological anlysis of 310 biopsied cases were performed. Method: We conducted retrospective study with review of histopathologic findings and clinical manifestations of the 310 cases diagnosed as glomerulonephritis by percutaneous renal biopsy which were done between January 1986 and December 1996 at department of pediatrics, Pusan Paik hospital. Results: 1) Male to female ratio was 1.54:1 and the range of age was from 13 months to 15 years 10 months. 2) Among these, 217 (70.0%) patients were belong to primary GN and 93 (30.0%) patients were belong to secondary GN. As a whole, the most common pathologic diagnosis was minimal change lesion (MC, 32.6%), which was followed by IgA nephropathy (IgAN, 15.8%), $Henoch-Sch\"{o}nlein$ purpura nephritis (HSPN, 13.5%), Poststreptococcal glomerulonephritis (PSAGN, 8.1%). 3) Clinical manifestations of patients were asymptomatic urinary abnormality (43.2%), nephrotic syndrome (41.0%), acute glomerulonephritis (14.2%), chronic glomerulonephritis (1.0%), rapidly progressive glomerulonephritis (0.6%). 4) In primary GN, the most common pathologic diagnosis was MC (46.5%), IgAN (22.6%), thin glomerular basement membrane (GBM) disease (7.8%), membranoproliferative glomerulonephritis (MPGN, 5.5%), mesangial proliferative glomerulonephritis (MesPGN,4.6%), focal segmental glomerulosclerosis (FSGS, 4.6%), membranous nephropathy (MN, 0.9%), sclerosing glomerulonephritis (SCGN, 0.9%), crescentic glomerulonephritis (CreGN, 0.5%) and non-specific glomerulonephritis (NonspGN, 6.0%). 5) Major causes of secondary GN were HSPN (45.2%), PSAGN (26.9%), hepatitis B associated glomerulonephritis (HBGN, 17.2%), lupus nephritis (LN, 6.5%), Alport syndrome (2.2%), hemolytic uremic syndrome (1.0%), fibrillary glomerulonephritis (1.0%) in descending order. Conclusions: There are some differences of the results of clinicopathological stuidies of glomerulonephritis in children because of its different indications of renal biopsy, pathologic classification of renal disease and methods of analysis among investigators. In order to establish more reliable data of incidence and classification of childhood glomerulonephritis in Korea, multicenter cooperative study were necessary.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.329-334
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• 2010

Escherichia coli O157:H7 causes hemolytic uremic syndrome and hemorrhagic colitis in humans. The objectives of this study were to produce monoclonal antibody(MAb) against E. coli O157:H7 and to develop an enzyme linked immunosorbent assay(ELISA) for the rapid detection of E. coli O157:H7 in agri-stockbreeding. The characterization of MAb produced from hybridoma cell (HKEC 4G8-5) was validated by ELISA and Western blot. The produced MAb was specific to E. coli O157:H7 and showed weak cross-reaction to Staphylococcus aureus. The detection limit of ELISA based on 4G8-5 MAb was $10^5\;cell/mL$. Although the ELISA could not detect E. coli O157:H7 in the meat and sprout samples inoculated with $1{\times}10^1\;cell$/10 g without enrichment, the same samples after enrichment for 6 hr were confirmed to be positive by ELISA. These results indicated that the ELISA combined with short enrichment (6 hr) is useful tool for rapid screening of E. coli O157:H7 in various samples.