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: 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

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: 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

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: Carrying antimicrobial resistance genes is a burden to bacteria. Therefore, in the absence of antimicrobial selective pressure, susceptible bacteria are expected to replace resistant ones. The cost was reported to decrease with time, but the effect of different species of susceptible bacteria on extended-spectrum -lactamase (ESBL)-, AmpC beta-lactamase-, and VIM-2 metallo-beta-lactamase-producing gram-negative bacilli are not known. The aim of this study was to determine the effect in vitro. METHODS: Antimicrobial-susceptible and -resistant strains of Escherichia coli, Enterobacter aerogenes, Klebsiella p neumoniae, and Acinetobacter baumannii were subcultured daily in glucose limited minimal salt medium at 30degrees C and 37degrees C, and the numbers of cells (CFU/mL) were determined by culturing on Mueller-Hinton agar and MacConkey agar plates. RESULTS: Continued incubation without subculture of both individual and mixed cultures at 37degrees C showed higher counts of a ESBL-producing K. p neumoniae than a susceptible E. coli. Daily subcultures of two strains in a tube showed the counts were : ESBL-producing K. pneumoniae >susceptible E. coli; susceptible E. aerogenes >ESBL-producing K. p neumoniae; susceptible E. aerogenes >VIM-2-beta-lactamase-producing Acinetobacter baumannii. The counts were similar for susceptible K. p neumoniae and AmpC beta-lactamasehyperproducing E. aerogenes. Initial low count of a susceptible E. coli and an ESBL-producing K. p neumoniae at 30degrees C gradually increased with continued subculture. CONCLUSION: Growth of not all resistant bacteria are slower and the growth improves with continued subculture. Coexistence of a susceptible bacteria with resistant bacteria in GLMS medium both at 30degrees C and 37degrees C does not reduce the number of resistant bacteria.
Acinetobacter baumannii ; Agar ; Anti-Infective Agents* ; Bacteria ; Enterobacter aerogenes ; Escherichia coli ; Glucose ; Klebsiella ; Pneumonia

BACKGROUND AND OBJECTIVES: The purpose of this study was to examine whether the different etiologies of intrauterine growth restriction (IUGR) produce different autonomic nervous modulation and instability of the fetal heart rate (FHR) regulation. SUBJECTS AND METHODS: We investigated the frequency-domain variability and instability in the FHR from 150 uneventful pregnancies (control group), 47 pregnancies with idiopathic IUGR (iIUGR group) and 48 with IUGR associated with severe pre-eclampsia of the mother (PEIUGR group). The FHR was analyzed for the power spectrum and very short-term intermittency (C1alpha), which are used to quantify the instability in FHR. RESULTS: Compared to the control group, the iIUGR group showed significantly increased low- and high-frequency powers (LFP and HFP, respectively). In contrast, the PEIUGR group showed significantly decreased LFP and LFP/HFP ratio, but significantly increased C1alpha compared to the control and iIUGR groups. CONCLUSION: The IUGR of an idiopathic cause produces abnormally increased the autonomic modulation of the FHR. In contrast, the IUGR due to pre-eclampsia abnormally decreased the autonomic modulation in the low-frequency range, but increased the instability of the fetal heart rate regulation.
Autonomic Nervous System ; Female ; Fetal Growth Retardation ; Fetal Heart* ; Heart Rate, Fetal* ; Humans ; Mothers ; Pre-Eclampsia ; Pregnancy