1.Biological characteristics and serovars of vibrio vulnificus.
Shin Moo KIM ; Yeal PARK ; Yunsop CHONG
Journal of the Korean Society for Microbiology 1991;26(5):403-415
No abstract available.
Population Characteristics*
;
Vibrio vulnificus*
;
Vibrio*
2.Haemophilus influence isolated from sputum specimens: prevalence biotypes and antimicrobial susceptibility.
Yunsop CHONG ; Kyung Soon SONG ; Chik Hyun PAI ; Eui Chong KIM ; Tae Yeal CHOI
Korean Journal of Infectious Diseases 1992;24(2):107-113
No abstract available.
Haemophilus*
;
Prevalence*
;
Sputum*
3.Haemophilus influence isolated from sputum specimens: prevalence biotypes and antimicrobial susceptibility.
Yunsop CHONG ; Kyung Soon SONG ; Chik Hyun PAI ; Eui Chong KIM ; Tae Yeal CHOI
Korean Journal of Infectious Diseases 1992;24(2):107-113
No abstract available.
Haemophilus*
;
Prevalence*
;
Sputum*
4.(99m)Tc Generator Safety Simulation Based on GEANT4.
Sung Koo KANG ; Dong Hyun HAN ; Chong Yeal KIM
Korean Journal of Medical Physics 2008;19(1):1-8
Technisium ((99m)Tc) is one of the most widely used radioactive isotopes for diagnosis in nuclear medicine. In general, technisium is produced inside the so called (99m)Tc generator which is usually made out of lead to shield relatively high energy radiation from (99)Mo and its daughter nuclide (99m)Tc. In this paper, a GEANT4 simulation is carried out to test the safety of the (99m)Tc generator, taking the Daiichi product with radioactivity of 500 mCi as an example. According to the domestic regulation on radiation safety, the dose at 10 cm and 100 cm away from the surface of shielding container should not exceed 2.0 mSv/h and 0.02 mSv/h, respectively. The simulated dose turned out to be less than the limit, satisfying the domestic regulation.
Nuclear Family
;
Nuclear Medicine
;
Radioactivity
;
Radioisotopes
5.Korean Nationwide Surveillance of Antimicrobial Resistance in 2000 with Special Reference to Vancomycin Resistance in Enterococci, and Expanded-Spectrum Cephalosporin and Imipenem Resistance in Gram-Negative Bacilli.
Kyungwon LEE ; Moon Yeun KIM ; Sung Ha KANG ; Jung Oak KANG ; Eui Chong KIM ; Tae Yeal CHOI ; Yun Sop CHONG
Yonsei Medical Journal 2003;44(4):571-578
Antimicrobial resistance surveillance is necessary to determine the size of the problem and to guide empirical selection of antimicrobial agents for treating infected patients. The aim of this study was to analyze the results of susceptibility tests performed by hospitals participating in the Korean Nationwide Surveillance of Antimicrobial Resistance (KONSAR) program. The rates of oxacillin-resistant staphylococci, penicillin-nonsusceptible pneumococci, and ampicillin-resistant E. faecium were over 70%. Ampicillin-resistant H. influenzae increased to 68%. Expanded-spectrum cephalosporin-resistant K. pneumoniae, fluoroquinolone-resistant E. coli, and imipenem-resistant P. aeruginosa remained at 16% through 27%, depending on the species. The proportions of vancomycin-resistant E. faecium and imipenem-resistant P. aeruginosa were 18 - 24% and 19-21%, respectively, indicating the seriousness of antimicrobial resistance. In conclusion, the increasing prevalence of resistant bacteria indicates that more concerted effort is required to conserve the usefulness of precious new antimicrobial agents.
Anti-Bacterial Agents/*pharmacology
;
Cephalosporins/*pharmacology
;
*Drug Resistance, Microbial
;
Enterococcus/*drug effects
;
Gram-Negative Bacteria/*drug effects
;
Human
;
Imipenem/*pharmacology
;
Korea
;
*Vancomycin Resistance
6.Antimicrobial Resistance of Clinically Important Bacteria Isolated from 12 Hospitals in Korea in 2005 and 2006.
Hyukmin LEE ; Chang Ki KIM ; Jongwook LEE ; Sung Hee LEE ; Ji Young AHN ; Seong Geun HONG ; Yeon Jun PARK ; Seok Hoon JEONG ; Eui Chong KIM ; Wee Kyo LEE ; Young UH ; Jong Hee SHIN ; Tae Yeal CHOI ; Hyo Sun KWAK ; Kyungwon LEE
Korean Journal of Clinical Microbiology 2007;10(1):59-69
BACKGROUND: Emergence and spread of antimicrobial resistant bacteria make it difficult to treat infections. A rapid increase in antimicrobial-resistant bacteria has become a serious problem in many countries including Korea, and it is important to perform a nationwide study of antimicrobial resistance to obtain some basic data that will help solve these problems. The aim of this study was to determine the nationwide prevalence of resistance among frequently isolated bacterial pathogens in 2005 and 2006 in Korea. METHODS: We collected routine susceptibility data for medically important bacterial pathogens from 12 university and general hospital laboratories in Korea from April to September in 2005 and from January to June in 2006. Collected data was analyzed by patient group. RESULTS: The proportions of methicillin-resistant Staphylococcus aureus (MRSA) were 65% in 2005 and 72% in 2006, respectively. The resistance rates of Enterococcus faecium to vancomycin were 29% in 2005 and 24% in 2006. The non-susceptible rates of Streptococcus pneumoniae to penicillin were 68% in 2005 and 74% in 2006. The resistant rates of Escherichia coli and Klebsiella pneumoniae to the 3rd generation cephalosporin were 10~12% and 25~39%, respectively, in 2005 and 11~15% and 30~34% in 2006. In Citrobacter freundii, Enterobacter cloacae and Serratia marcescens, the resistance rates to 3rd generation cephalosporin were 23~31%, 32~34%, and 17~27%, respectively, in 2005 and 21~37%, 37~43%, and 13~31% in 2006. The resistance rates to imipenem and meropenem were 21% and 18%, respectively, in Pseudomonas aeruginosa and 18% and 25% in Acinetobacter baumannii in 2005; 29% and 20% in P. aeruginosa and 18% and 23% in A. baumannii in 2006. Cotrimoxazole and levofloxacin resistance rates of Stenotrophomonas maltophilia were 5% and 13%, respectively, in 2005 and 3% and 7% in 2006. There were no isolates resistant to 3rd generation cephalosporin and fluoroquinolone among non-typhoidal Salmonella in 2005. CONCLUSION: Antimicrobial resistance of medically important bacteria is still a serious problem in Korea. To manage the problem, a continuous nationwide surveillance and diversified investigation and effort have become more important.
Acinetobacter baumannii
;
Bacteria*
;
Citrobacter freundii
;
Enterobacter cloacae
;
Enterococcus faecium
;
Escherichia coli
;
Hospitals, General
;
Humans
;
Imipenem
;
Klebsiella pneumoniae
;
Korea*
;
Levofloxacin
;
Methicillin-Resistant Staphylococcus aureus
;
Penicillins
;
Prevalence
;
Pseudomonas aeruginosa
;
Salmonella
;
Serratia marcescens
;
Stenotrophomonas maltophilia
;
Streptococcus pneumoniae
;
Trimethoprim, Sulfamethoxazole Drug Combination
;
Vancomycin
7.Emergence of CTX-M-12, PER-1 and OXA-30 beta-Lactamase-Producing Klebsiella pneumoniae.
Il Kwon BAE ; Yu Nae LEE ; Seok Hoon JEONG ; Kyungwon LEE ; Dongeun YONG ; Jongwook LEE ; Seong Geun HONG ; Eui Chong KIM ; Yeon Jun PARK ; Tae Yeal CHOI ; Young UH ; Jong Hee SHIN ; Wee Gyo LEE ; Ji Young AHN ; Sung Hee LEE ; Gun Jo WOO ; Hyo Sun KWAK
Korean Journal of Clinical Microbiology 2006;9(2):102-109
BACKGROUND: The aim of this study was to determine a nation-wide prevalence of Ambler class A and D extended-spectrum-lactamases (ESBL) in Klebsiella pneumoniae isolates in Korea. METHODS: During the period of April to May 2005, 189 isolates of K.pneumoniae were collected from 11 Korean hospitals. Antimicrobial susceptibilities to ceftazidime and cefotaxime were tested by the disk diffusion method, and ESBL production was determined by double-disk synergy test. Determinants of ceftazidime or cefotaxime-resistance were transferred to Escherichia coli J53 (azide-resistant) by transconjugation. Genotypes of class A and D ESBL genes were determined by PCR amplification and sequencing. RESULTS: One hundred-sixty isolates of K.pneumoniae showed positive results in double-disk synergy test. The most prevalent ESBL was SHV-12 (n=148). Also detected were genes encoding ESBLs including TEM-52 (n=1), SHV-2a (n=2), CTX-M-3 (n=15), CTX-M-9 (n=6), CTX-M-12 (n=2), CTX-M-14 (n=9), CTX-M-15 (n=1), PER-1 (n=1), GES-5 (n=3), and OXA-30 (n=2) beta-lactamases. CONCLUSION: With the emergence of CTX-M-12, PER-1, and OXA-30 beta-lactamases, the ESBLs in K.pneumoniae isolates are becoming more diverse in Korea.
beta-Lactamases
;
Cefotaxime
;
Ceftazidime
;
Diffusion
;
Escherichia coli
;
Genotype
;
Klebsiella pneumoniae*
;
Klebsiella*
;
Korea
;
Polymerase Chain Reaction
;
Prevalence
8.Antimicrobial Resistance of Clinically Important Bacteria Isolated from 12 Hospitals in Korea.
Seong Geun HONG ; Jongwook LEE ; Dongeun YONG ; Eui Chong KIM ; Seok Hoon JEONG ; Yeon Jun PARK ; Tae Yeal CHOI ; Young UH ; Jong Hee SHIN ; Wee Kyo LEE ; Ji Young AHN ; Sung Hee LEE ; Gun Jo WOO ; Kyungwon LEE
Korean Journal of Clinical Microbiology 2004;7(2):171-177
BACKGROUND: A rapid increase in antimicrobial-resistant bacteria has become a serious problem in Korea. Moreover, the antibiotic resistance problem has worsened noticeably during the past several years. The aim of this study was to determine the prevalence of resistance among frequently isolated gram-positive and -negative bacteria in Korea. METHODS: Routine susceptibility data for medically important bacteria isolated during 6 months of 2003 were collected from 12 university and general hospital laboratories in Korea. RESULTS: The proportion of methicillin-resistant Staphylococcus aureus (MRSA) was 66%; however, vancomycin-resistant strains were not detected. The rates of vancomycin-resistant Enterococcus faecium and penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) were 22% and 73%, respectively. The resistance rates to 3rd generation cephalosporins and monobactam were: Escherichia coli 8-12%, Klebsiella pneumoniae 18-22%, Citrobacter freundii 22-32%, Enterobacter cloacae 34-37%, and Serratia marcescens 12-21%, respectively. Imipenem resistance rates of Acinetobacter baumannii and Pseudomonas aeruginosa were 23% and 25%, respectively. CONCLUSIONS: Antimicrobial resistant strains were already prevalent among the clinically important isolates, especially, MRSA, PNSP, and extended-spectrum cephalosporin resistant gram-negative bacilli in Korea. The imipenem-resistant rates of A. baumannii and P. aeruginosa increased, respectively, from 13% and 20% in 2002 to 23% and 25% in 2003. The results of this study will provide a basis for proper treatment of bacterial infections and prevention of spread of resistant bacteria. A continuous nationwide surveillance of antimicrobial resistance is very important and should be performed.
Acinetobacter baumannii
;
Bacteria*
;
Bacterial Infections
;
Cephalosporins
;
Citrobacter freundii
;
Drug Resistance, Microbial
;
Enterobacter cloacae
;
Enterococcus faecium
;
Escherichia coli
;
Hospitals, General
;
Imipenem
;
Klebsiella pneumoniae
;
Korea*
;
Methicillin-Resistant Staphylococcus aureus
;
Prevalence
;
Pseudomonas aeruginosa
;
Serratia marcescens
;
Streptococcus pneumoniae
9.Antimicrobial Resistance of Clinically Important Bacteria Isolated from 12 Hospitals in Korea in 2004.
Hyukmin LEE ; Dongeun YONG ; Kyungwon LEE ; Seong Geun HONG ; Eui Chong KIM ; Seok Hoon JEONG ; Yeon Jun PARK ; Tae Yeal CHOI ; Young UH ; Jong Hee SHIN ; Wee Kyo LEE ; Jongwook LEE ; Ji Young AHN ; Sung Hee LEE ; Gun Jo WOO
Korean Journal of Clinical Microbiology 2005;8(1):66-73
BACKGROUND: A rapid increase in antimicrobial-resistant bacteria has become a serious problem in many countries including Korea, but the rate and pattern of antimicrobial resistance may vary significantly depending on countries and even on hospitals. The aim of this study was to determine the nationwide prevalence of resistance among frequently isolated bacterial pathogens in Korea. METHODS: Routine susceptibility data for medically important bacterial pathogens from 12 university hospital and general hospital laboratories in Korea were analysed by patient group. These pathogens had been isolated during the period from April to November in 2004. RESULTS: The proportion of methicillin-resistant Staphylococcus aureus (MRSA) was 67%. Van-comycin-resistance rate of Enterococcus faecalis was 1% and that of E.faecium was 20%. The resistance rates of Streptococcus pneumoniae to penicillin and Haemophilus influenzae to ampicillin were 70% and 54%, respectively. The resistant rates of Escherichia coli and Klebsiella pneumoniae were 7-10% and 26-31% to the 3rd generation cephalosporin, respectively. The resistance rates to 3rd generation cephalosporin were 22-30% in Citrobacter freundii, 35-44% in Enterobacter cloacae and 15-22 % in Serratia marcescens. Imipenem resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii were 26% and 17%. Cotrimoxazole and levofloxacin resistance rates of Stenotrophomonas maltophilia were 46% and 44%, respectively. CONCLUSION: Antimicrobial resistance rates of clinically important pathogens in Korea were still high and were generally higher among the bacteria isolated from the intensive care unit patients. Strict infection control and continuous nationwide surveillance program will be required to manage the antimicrobial resistance problem.
Acinetobacter baumannii
;
Ampicillin
;
Bacteria*
;
Citrobacter freundii
;
Enterobacter cloacae
;
Enterococcus faecalis
;
Escherichia coli
;
Haemophilus influenzae
;
Hospitals, General
;
Humans
;
Imipenem
;
Infection Control
;
Intensive Care Units
;
Klebsiella pneumoniae
;
Korea*
;
Levofloxacin
;
Methicillin-Resistant Staphylococcus aureus
;
Penicillins
;
Prevalence
;
Pseudomonas aeruginosa
;
Serratia marcescens
;
Stenotrophomonas maltophilia
;
Streptococcus pneumoniae
;
Trimethoprim, Sulfamethoxazole Drug Combination
10.Mechanism of VanB Phenotype in Vancomycin-Resistant Enterococci carrying vanA gene.
Il Joong PARK ; Wee Gyo LEE ; Hyukmin LEE ; Dongeun YONG ; Kyungwon LEE ; Eui Chong KIM ; Seok Hoon JEONG ; Yeon Jun PARK ; Tae Yeal CHOI ; Young UH ; Jong Hee SHIN ; Jongwook LEE ; Ji young AHN ; Sung Hee LEE ; Gun Jo WOO
The Korean Journal of Laboratory Medicine 2006;26(6):412-417
BACKGROUND: Recently, vancomycin-resistant enterococci (VRE) with the vanA genotype that are susceptible to teicoplanin have been described in Japan, Taiwan, and Korea. The investigators suggested three point mutations in the putative sensor domain of vanS or impairment of accessory proteins VanY and VanZ as an explanation for the VanB phenotype-vanA genotype VRE. In this study, we analyzed Tn1546-like elements to determine the molecular mechanisms responsible for the impaired glycopeptide resistance of clinical VRE isolates with VanB phenotype-vanA genotype from Korea. METHODS: From 2001 to 2004, 28 clinical isolates of Enterococcus faecium with VanB phenotypevanA genotype were collected from 8 different university hospitals in diverse geographic areas in Korea. For structural analysis of Tn1546-like elements, PCR amplifications for internal regions of Tn1546 were performed. The purified PCR products were directly sequenced with an ABI Prism 3100 DNA sequencer. RESULTS: The sequence data of the vanS regulatory gene revealed that none of the isolates had any point mutations in this gene. All 28 isolates had a complete or incomplete deletion of vanY gene. Of these, 13 strains represented a complete deletion of vanZ, and 2 strains showed the deletion of nucleotides near the end point of vanX. CONCLUSIONS: The mechanism of VanB phenotype-vanA genotype in VRE isolates from Korea is not point mutations of vanS but the rearrangements of vanX, vanY and vanZ.
DNA
;
Enterococcus faecium
;
Genes, Regulator
;
Genotype
;
Hospitals, University
;
Humans
;
Japan
;
Korea
;
Nucleotides
;
Phenotype*
;
Point Mutation
;
Polymerase Chain Reaction
;
Research Personnel
;
Taiwan
;
Teicoplanin