No abstract available.
Female ; Fetal Heart* ; Fractals* ; Heart Rate, Fetal* ; Pregnancy

Antimicrobial resistance, plasmid profile, and ribotype were determined from the 49 strains of Shigella sonnei isolated from 1992 to 1994 in Korea. Four patterns of antimicrobial resistance were shown. Based on the and microbial resistance test, 49 isolates of Shigella sonnei showed resistance to at least one antimicrobial drugs. These Shigella sonnei isolates are placed into 7 different plasmid profiles. Thirty-eight strains showed pattern III and pattern IV. From endonuclease analysis, twelve (Hind III), nine (Bam HI), seventeen (Eco RI) patterns of plasmid profile were shown. To determine whether ribotyping could be used to distinguish among Shiglla sonnei isolates, Southern hybridization studies were conducted. Shigella sonnri genomic DNA fragments by digestion with Sal I and ribotyping revealed five distinct patterns of ribotype (strains with patterns I, II, III, IV, and V) after hybridization with Escherichia coli 16s and 23s rRNAs. Compared with Sal I only a single pattern of ribotype by Hinc II was found. According to these data, Shigella sonnei strains in Korea seemed to be more than five clones. However, we cannot find consistent relationship among antimicrobial resistance, plasmid profile, and ribotyping. Thus it is needed to consider antimicrobial resistance, plasmid profile, and ribotyping for the epidemiological study of Shigella sonnei in Korea.
Clone Cells ; Digestion ; DNA ; Drug Resistance, Microbial ; Escherichia coli ; Korea* ; Plasmids ; Ribotyping* ; Shigella sonnei* ; Shigella*

BACKGROUND: Clinical isolates of AmpC beta-lactamase- producing Enterobacteriaceae were evaluated to determine the prevalence of CTX-M extended-spectrum beta-lactamases (ESBLs) and their genetic environments. METHODS: A total of 250 non-duplicate isolates of Eneterobacter aerogenes, E. cloacae, Citrobacter freundii, Serratia marcescens and Morganella morganii were collected at a Korean hospital. ESBL production was determined by double disk synergy test. For ESBL producers, bla genes were sequenced and blaCTX-M environment was characterized by PCR mapping and sequencing. RESULTS: Among the 250 isolates 29 (11.6%) produced ESBL, and 14 of the 29 isolates produced CTX-M ESBLs, including CTX-M-9 by 8 isolates, CTX-M-3 by 4 isolates, CTX-M-12 by 1 isolate, and CTX-M-14 by 1 isolate. ISEcp1 was present upstream of blaCTX-M-3, 12, and 14. Three of the four CTX- M-3 producers had the same genetic environment (pemK-ISEcp1-blaCTX-M-3-orf477-mucA). An IS903-like element was found downstream of blaCTX-M-14. ISCR1 was identified upstream of blaCTX-M-9 and ISCR1 and blaCTX-M-9 were located on sul1-type class 1 integron. The variable region between the 5'-CS and the first 3'-CS contained dfrA16 and aadA2. Its structure was similar to that of In60, but our isolates did not have IS3000 or second 3'-CS. CONCLUSION: CXT-M type ESBL was prevalent in AmpC beta-lactamase-producing Enterobacteriaceae, particularly E. cloacae. blaCTX-M genes were associated with ISEcp1 or ISCR1. This is the first report on the genetic environment of blaCTX-M in Korean isolates.
beta-Lactamases ; Citrobacter freundii ; Cloaca ; Enterobacteriaceae ; Integrons ; Korea ; Morganella morganii ; Polymerase Chain Reaction ; Prevalence ; Serratia marcescens

Clindamycin resistance in Staphylococcus species can be either constitutive or inducible. Inducible resistance cannot be detected by the conventional antimicrobial susceptibility test. In this study, we determined the prevalence of inducible clindamycin resistance in staphylococcal isolates at a Korean tertiary care hospital. Between February and September 2004, 1,519 isolates of Staphylococcus aureus and 1,043 isolates of coagulase-negative staphylococci (CNS) were tested for inducible resistance by the D-zone test. Overall, 17% of MRSA, 84% of MSSA, 37% of MRCNS, and 70% of MSCNS were susceptible to clindamycin. Of the erythromycin non-susceptible, clindamycin-susceptible isolates, 32% of MRSA, 35% of MSSA, 90% of MRCNS, and 94% of MSCNS had inducible clindamycin resistance. Inducible clindamycin resistance in staphylococci was highly prevalent in Korea. This study indicates importance of the D-zone test in detecting inducible clindamycin resistance in staphylococci to aid in the optimal treatment of patients.
Staphylococcus aureus/metabolism ; Staphylococcal Infections/*metabolism ; Prevalence ; *Microbial Sensitivity Tests ; Korea ; Humans ; Drug Resistance, Multiple, Bacterial ; *Drug Resistance, Microbial ; Clindamycin/*pharmacology ; Anti-Infective Agents/*pharmacology ; Anti-Bacterial Agents/*pharmacology

BACKGROUND: Recently a novel plasmid-mediated resistant mechanism that conferred high-level resistance to aminoglycoside via methylation of 16S rRNA was reported. The aims of this study were to determine the prevalence of the 16S rRNA methylase genes and to characterize the coresistance to other antibiotics in Gram-negative bacilli. METHODS: Consecutive non-duplicate Gram-negative bacilli were isolated from clinical specimens at a Korean secondary- and tertiary-care hospital from July 2006 to June 2007. The antimicrobial susceptibility was tested by the CLSI agar dilution method,and PCR was performed to detect the 16S rRNA methylase genes in the arbekacin-resistant isolates. RESULTS: In Gram-negative bacilli, the proportions of 16S rRNA methylase gene-positive isolates were 5% (75/1,471) in the secondary-carehospital and 4% (48/1,251) in the tertiary-care hospital, and the positive rates by species were 1% Escherichiae coli 16% (10/1,062), Klebsiella pneumoniae 16% (75/460), K. oxytoca 2% (1/44), Citrobacter spp. 9% (7/82), Enterobacter spp. 2% (4/181), Serratia marcescens 6% (6/100), Proteus miriabilis 4% (2/57), Achromobacter xylosoxidans 20% (1/5), Pseudomonas aeruginosa < 1% (1/505), Acinetobacter spp. 10% (11/112), and Stenotrophomonas maltophilia 2% (1/66), respectively. Among 16S rRNA methylase-positive isolates from secondary- and tertiary-care hospitals, 93% (70/75) and 90% (43/48), respectively, were armA positive, and others, except one rmtA positive isolate, were positive for the rmtB gene, according to PCR results. The rates of ESBL-positive and cefoxitin-resistant K. pneumoniae were 59% and 92%,s respectively. In addition, 91% of 16S rRNA methylase-producing K. pneumoniae were positive for qnrB. There were no MBL producers among 16S rRNA methylase-producing Pseudomonas and Acinetobacter species. CONCLUSION: The novel aminoglycoside-resistant mechanisms involving16S rRNA methylase were prevalent and widely distributed among Gram-negative bacilli in Korea, and other resistance mechanisms were commonly associated with 16S rRNA methylase-mediated resistance in Korea.
Achromobacter denitrificans ; Acinetobacter ; Agar ; Anti-Bacterial Agents ; Citrobacter ; Enterobacter ; Escherichia ; Klebsiella pneumoniae ; Korea ; Methylation ; Methyltransferases ; Pneumonia ; Polymerase Chain Reaction ; Prevalence ; Proteus ; Pseudomonas ; Pseudomonas aeruginosa ; Serratia marcescens ; Stenotrophomonas maltophilia

No Abstract available.
Fetus* ; Heart Rate* ; Heart* ; Pre-Eclampsia*

BACKGROUND: Panipenem is a carbapenem antimicrobial agent which has been shown to have broad-spectrum activities against various aerobic and anaerobic bacteria. In this study, in vitro activities of panipenem against recent clinical isolates of aerobic and anaerobic bacteria were determined. METHODS: Aerobic and anaerobic bacteria were isolated in 2001 and in 2000-2001, respectively, from a tertiary-care hospital patients. Antimicrobial susceptibility was tested by the NCCLS agar dilution method. RESULTS: MIC90s of panipenem were:similar to those of imipenem for aerobic gram-positive cocci and Enterobacteriaceae; slightly lower than those of meropenem for gram-positive cocci, but slightly higher for Enterobacteriaceae; slightly higher than imipenem for A. baumannii, but similar for anaerobic bacteria. CONCLUSION: MIC90s of panipenem were similar to those of imipenem for aerobic and anaerobic bacterial isolates, which frequently involve respiratory, urinary, intraabdominal and wound infections. When imipenem breakpoints are applied to interpret panipenem susceptibilities, panipenem can be considered useful for the treatment of various infections, including nosocomially acquired ones.
Agar ; Bacteria, Anaerobic* ; Enterobacteriaceae ; Gram-Positive Cocci ; Humans ; Imipenem ; Wound Infection

BACKGROUND: Panipenem is a carbapenem antimicrobial agent which has been shown to have broad-spectrum activities against various aerobic and anaerobic bacteria. In this study, in vitro activities of panipenem against recent clinical isolates of aerobic and anaerobic bacteria were determined. METHODS: Aerobic and anaerobic bacteria were isolated in 2001 and in 2000-2001, respectively, from a tertiary-care hospital patients. Antimicrobial susceptibility was tested by the NCCLS agar dilution method. RESULTS: MIC90s of panipenem were:similar to those of imipenem for aerobic gram-positive cocci and Enterobacteriaceae; slightly lower than those of meropenem for gram-positive cocci, but slightly higher for Enterobacteriaceae; slightly higher than imipenem for A. baumannii, but similar for anaerobic bacteria. CONCLUSION: MIC90s of panipenem were similar to those of imipenem for aerobic and anaerobic bacterial isolates, which frequently involve respiratory, urinary, intraabdominal and wound infections. When imipenem breakpoints are applied to interpret panipenem susceptibilities, panipenem can be considered useful for the treatment of various infections, including nosocomially acquired ones.
Agar ; Bacteria, Anaerobic* ; Enterobacteriaceae ; Gram-Positive Cocci ; Humans ; Imipenem ; Wound Infection

BACKGROUND: Enterococcus gallinarum, an organism often found in the intestine, is intrinsically resistant to low level vancomycin, but some of them are highly resistant to vancomycin due to acquisition of vanA gene. We occasionally detected both vanA carrying E. gallinarum and E. faecalis or E. faecium in the same patients, suggesting transfer of the resistance gene from the latter. In this study, the structures of Tn1546-like elements in E. gallinarum, and E. faecalis or E. faecium from the same patients were compared to determine the clinical significance of the vanA genotype E. gallinarum isolates. METHODS: Six pairs of vanA genotype E. gallinarum and E. faecalis or E. faecium were isolated at a tertiary- care hospital in Korea during 2000 to 2004. Species identification was performed by conventional methods. and the vancomycin-resistance genotypes were determined by PCR. For structural analysis of Tn1546-like elements, overlapping PCR amplification and sequencing of the internal regions were performed. RESULTS: All isolates were positive for vanA genes by PCR. The analysis of Tn1546-like elements showed structurally related three types of distribution of IS elements integrated: Type I had insertion of an IS1542 in the orf2-vanR intergenic region, and an IS1216V in the vanX-vanY intergenic region. Type II was similar with Type I but accompanied with the partial and complete deletions of orf1 and orf2. Type III had an IS1216V and an IS1542 in the orf2-vanR intergenic region, and an IS1216V in the vanX-vanY intergenic region. Two of the six vanA clusters in E. gallinarum isolates had structures identical to those in E. faecalis or E. faecium strains isolated from the same patients. However, in some isolate pairs, the origin of Tn1546 cannot be determined, because the structures were not identical, and colonization of multiple clones was supposed. CONCLUSION: vanA clusters in some E. gallinarum, and in E. faecalis or E. faecium isolates from the same patients had an identical structure, indicating their transfer from the latter. It is assumed that vanA type E. gallinarum can act as a reservoir of vanA gene for interspecies spread.
Clone Cells ; Colon ; DNA Transposable Elements ; DNA, Intergenic ; Enterococcus* ; Genotype* ; Humans ; Intestines ; Korea ; Lifting ; Polymerase Chain Reaction ; Vancomycin

BACKGROUND: Gram-negative bacilli can be stored in cystine tryptic agar (CTA) at room temperature for over 1 year, but we experienced a loss of imipenem resistance among VIM-2-producing isolates. The aims of this study were to determine the frequency of loss of IMP-1 and VIM-2 genes during storage in CTA at room temperature and to document any change in the MIC of antimicrobial agents and the location of the gene. METHODS: Bacteria were isolated from clinical specimens at Severance Hospital collected from 1995-2000. Modified Hodge and double disk synergy tests were performed for screening of MBL-production isolates, and blaIMP-1 and blaVIM-2 were detected by PCR. Loss of resistance was tested in CTA at room temperature. PFGE and hybridization using a blaVIM-2 probe were carried out to determine the location of the VIM-2 gene. RESULTS: When VIM-2- and IMP-1-producing strains of eight P. aeruginosa and two Acinetobacter spp. were stored in CTA at room temperature, some isolates lost imipenem resistance after 3 days and 90% lost resistance after 15 weeks. Loss of resistance genes resulted in a decrease of the MIC of imipenem from 32-128 mug/mL to 0.5-8 mug/mL for P. aeruginosa, and from 32 mug/mL to 0.25-4 mug/mL for Acinetobacter spp. Hybridization of I-CeuI and S1-digested and PFGE suggested that VIM-2 genes are located on approximately 50-100 kb or 400 kb plasmids. CONCLUSION: Isolates may lose resistance genes when stored in CTA at room temperature. Therefore, it is necessary for MBL-production tests including the Modified Hodge test and double disk synergy test and detection of MBL genes.
Acinetobacter ; Agar ; Anti-Infective Agents ; Bacteria ; Carbapenems ; Chimera ; Cystine ; Imipenem ; Mass Screening ; Polymerase Chain Reaction ; Sprains and Strains