• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.213-218
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• 2014

The enterotoxin production and antimicrobial susceptibility on hemolytic strains from stools of diarrheal pigs was investigated in this study. Through morphological observation, gyrB nucleotide sequence, and API kit analysis, the selected potential pathogenic strain BY06 was identified as Bacillus cereus. Because the characteristic of enterotoxin symptoms were widely caused by Bacillus cereus strains, a PCR test was carried out in order to check the enterotoxin genes (hblA) in this strain. According to the results, this strain was an enterotoxin positive strain containing the hblA gene. The minimum inhibitory concentrations of 10 different antimicrobial agents were screened by the agar dilution test, indicating that this strain was resistant to penicillin G and intermediate to erythromycin; however, it susceptible to cephalothin, vancomycin, clindamycin, fusidic acid, gentamicin, ciprofloxacin, tetracycline and rifampin. These results suggest that the B. cereus BY06 isolated from pig feces has a potential risk of producing enterotoxin and is resistant to penicillin G, but susceptible to various antimicrobial agents.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.581-586
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• 2018

Enterococcus spp. have been considered major indicator organisms for antibiotic resistance due to their ability to easily acquire and to harbor antibiotic resistance. In this study, Enterococcus spp. were isolated from 174 retail fresh-cut products (fresh vegetable salads, microgreens, and sprouts) in Korea. Among the 20 Enterococcus isolates obtained, 18 (90.0%) were Enterococcus faecalis and 2 (10.0%) were Enterococcus faecium. The patterns of antibiotic resistance against nine antimicrobials were analyzed. Most of the isolates (85.0%) were resistant to quinupristin/dalfopristin, 40.0% and 50.0% of the isolates showed intermediate resistance to two critically important antimicrobials for human medicine, ciprofloxacin and erythromycin, respectively. Vancomycin-resistant enterococci were not detected in this study. Given the importance of antimicrobial resistance of enterococci in food safety as well as in public health, our results regarding the occurrence (level of contamination) and antimicrobial resistance of Enterococcus spp. could provide useful information that aids the risk analysis of antibiotic resistance.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.167-177
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• 2003

Purpose : To know the trends of antimicrobial susceptibility is critical for antimicrobial treatment. We studied the organisms isolated from blood, urine, stool, and cerebrospinal fluid from 1997 to 2001 to reveal the trends of their antimicrobial susceptibility. Methods : We conducted a retrospective study with isolates obtained from 0~18 year old outpatients and inpatients from 1997 to 2001 at Department of Pediatrics, Hanil general hospital. We gathered the data through the laboratory test files and the origin of microorganisms cultured from blood, urine, stool and cerebrospinal fluid and their antimicrobial susceptibility. Results : Microorganisms were isolated from 226(3.3%) out of 6,974 blood cultures, 365 (8.0%) out of 4,549 urine cultures, 50(1.9%) out of 2,593 stool cultures and 9(1.4%) in 655 cerebrospinal fluid cultures. The most frequently isolated organisms from blood cultures was Staphylococcus epidermidis(33.5%) which was followed by Staphylococcus aureus(19.7%), Escherichia coli(13.8%), and Burkholderia cepacia(9.0%). Among the urine cultures, E. coli was the most common(74.7%) which was followed by Group D Enterococcus(11.3%), Klebsiella pneumoniae(7.1%) and Proteus mirabilis(2.5%). The positive stool cultures all yield Salmonella species. Group D Salmonella was obtained most frequently. Among the positive cerebrospinal fluid cultures, Group B Streptococcus was isolated most frequently. Among the 40 cases of S. aureus in blood cultures, 27 cases were methicillin-resistant. The rates of susceptibility for amikacin, ceftizoxime and ceftriaxone of E. coli isolated from blood cultures were 80%, 100% and 60% in 1997 and 60%, 80% and 60% in 2001. The rates of susceptibility for amikacin, ceftizoxime and ceftriaxone of K. pnumoniae isolated from urine cultures. were 80%, 100% and 80% in 1997 and 50%, 83% and 50% in 2001 Enterococcus was isolated from 6.7% to 15.8% and vancomycin-resistant Enterococcus was observed in 17% of Group D Enterococcus isolated from urine cultures. The rates of susceptibility for amikacin, ceftizoxime and ceftriaxone of Group D Salmonella were 96%, 96% and 92% during the study period. Conclusion : Among the blood cultures S. epidermidis, S. aureus, E. coli and B. cepacia were isolated in order of frequency and among the urine cultures E. coli, Group D Enterococcus, K. pneumoniae and P. mirabilis were isolated in order of frequency. During the study period there was no big difference in major organisms isolated from blood and urine. The methicillin-resistant S. aureus was observed in 67% of S. aureus isolated from blood cultures but vancomycin-reistant S. aureus or vancomycin intermediate resistant S. aureus was not observed. The rates of susceptibility to amikacin and the third generation cephalosporin of E. coli isolated from blood cultures and K. pneumoniae from urine cultures have decreased. The isolation rates of Group D Enterococcus and vancomycin resistant Enterococcus have increased.

• Pediatric Infection and Vaccine
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• v.14 no.1
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• pp.83-90
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• 2007

Purpose : Staphylococcal scalded skin syndrome (4S) is a well known disease defined by clinical, microbiological and histological criteria caused by Staphylococcus aureus. This disease is uncommon but has been increasingly recognized. We investigated the clinical features of staphylococcal scalded skin syndrome. Methods : We reviewed retrospectively medical records of 53 patients diagnosis of staphylococcal scalded skin syndrome who were admitted to Changwon Fatima hospital from February 2002 to December 2005. These patients were divided into 3 clinical types; generalized type, intermediate type, abortive type. Age, sex ratio, clinical manifestations, laboratory findings, response to therapy and prognosis were investigated. Result : 1)The mean age of patients was 2.8 years, ranging from 20 days to 7 years. Male-to-female ratio was 1.9:1. 2) By clinical types, 6 patients were in the generalized type (11%), 29 patients in the intermediate type (55%), 18 patients in the abortive type (34%). The coexisting diseases were variable, including conjunctivitis (25 cases), atopic dermatitis (11 cases), otitis media (1 case). On laboratory findings, most of patients didn't have leukocytosis or increased C-reactive protein. 4) A total of fifteen Methicillin Resistant Staphylococcal Aureus (MRSA) strains were isolated from September 2003 through December 2005. Fourteen strains were positive for exfoliative toxin B gene by PCR and negative for enterotoxin, toxic shock syndrome toxin and Panton-Valentine leukocidin genes. 5) The mean duration of admission was 7.3 days. Patients were treated with vancomycin or amoxacillin/clavulanate or ampicillin/sulbactam or cefuroxime without significant sequelaes. Conclusion : Recently, Staphylococcal scalded skin syndrome caused by exfoliative toxin B produced by MRSA in the Changwon area has been increasing.

• Journal of fish pathology
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• v.10 no.2
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• pp.153-164
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• 1997

Characteristics and pathogenicity of Yersinia sp. strain isolated from diseased cultured olive flounder, Paralichthys olivaceous were studied. The causative organisms were identified as Yersinia sp. by biochemical and biophysical characteristics. The strain was named KF-1, and it showed the optimal growth rate at pH 9.0 and 1% NaCl. Total cell protein peptide bands of the Yersinia sp. KF-1 were between 14.4-100.6 Kd in molecular weight by the electrophoretic analysis, and a total of 28 bands appeared. The band found at 32.8 Kd in molecular weight was the major one of electrophoretic phase. In the pathogenicity test of the isolate to the flounder injecting with $1.0{\times}10^7$ cfu/fish 9 died out of 10 within 60 hrs, and in the group with $1.0{\times}10^7$ cfu/fish 5 died within 60 hrs. Thus the $LD_{50}$ was presumed to be $1.0{\times}10^7$ cfu/fish. In the drug sensitivity test KF-1 strain was sensitive to chloramphenicol, gentamycin, kanamycin, streptomycin and pefloxacin, and intermediate to erythromycin, and resistant to ampicillin, cephalothin, sulfamethoxazole/trimethoprim, tetracycline and vancomycin.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.799-808
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• 2021

This study was performed to investigate the extent of microbial contamination, the presence of enterotoxin genes, and the antibiotic susceptibility of Bacillus cereus in 58 red pepper plants and 43 environmental samples (soil, irrigation water, and gloves) associated with the plant cultivation. The detected counts of total aerobic bacteria, coliform bacteria, Escherichia coli, Bacillus cereus, and Staphylococcus aureus were lower in these samples, as compared to the regulations of standards for foods; moreover, pathogens, such as E. coli, E. coli O157:H7, Listeria monocytogenes, and Salmonella spp., were not detected. Genes encoding hemolysin BL enterotoxins (hblA, hblC, and hblD) as well as non-hemolytic enterotoxins (nheA, nheB, and nheC) were detected in 23 B. cereus specimens that were isolated from the test samples and had β-hemolytic activity. Interestingly, B. cereus is resistant to β-lactam and susceptible to non-β-lactam antibiotics. However, in this case, the isolated B. cereus specimens exhibited a shift from resistant to intermediate in response to cefotaxime and from susceptible to intermediate in case of rifampin, trimethoprim-sulfamethoxazole, vancomycin, clindamycin, and erythromycin. Therefore, the levels of B. cereus should be monitored to detect changes in antibiotic susceptibility and guarantee their safety.

• Pediatric Infection and Vaccine
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• v.15 no.2
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• pp.152-161
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• 2008

Purpose : Staphylococcal scalded skin syndrome (4S) is uncommon, but reports of 4S are on the increase during the recent years. The purpose of this study is to determine the clinical features and associated factors of 4S during the recent 10 years. Methods : We retrospectively reviewed the medical records and microbiologic results of 63 patients (27 neonates and 36 children) from January 1998 to December 2007. Results : Since 2003, the incidence of 4S has increased. The mean age of the patients was 16.3 months and the gender ratio was 1:1. The clinical types of 4S were 38 cases of the abortive type (60%), 19 cases of the intermediate type (30%) and 6 cases of the generalized type (10%). The culture results were 36 cases of Methicillin resistant S. aureus (MRSA), 4 cases of Methicillin sensitive S. aureus and 17 cases of no growth. The patients were treated with semi-synthetic penicillin. For the 9 patients who had MRSA isolated and who didn't improve with penicillin, they were treated with vancomycin instead of penicillin. All the patients had no complications. 4S abruptly increased in 2005, and especially in neonates, due to an MRSA outbreak at a local nursery room. The associated factors of 4S in neonates were hospitalization (27 cases), including nursery infection in 2005 (18 cases) and dermatitis (1 case). There was an unknown origin for some children, and the suggested factors for their infection were community acquired infection (24 cases), atopic dermatitis (9 cases) and hospitalization (3 cases). Conclusion : 4S has recently been increasing. The major associated factors of 4S are a history of hospitalization, an outbreak in a nursery room, atopic dermatitis and community acquired infection.