Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most prevalent dermatology pathogens in hospitals and increasingly recognized in communities. We determined PFGE pattern of SmaI-restricted genomic DNA, coagulase type, and antimicrobial susceptibility of MRSA isolated in 2008 from dermatology inpatients and healthy hospital employees in A Hospital and from primary school children in Iksan city, Korea. Overall, the isolation rate of MRSA was 3.8% from the 788 normal persons: 4.9% from hospital employees and 1.1% from primary school children. MRSA was isolated in six of 13 (46.2%) family members of four school children with MRSA. The most prevalent coagulase serotype was II from patients and V from healthy individuals. Ten of twenty and six of twenty MRSA isolates from patients and from healthy personnel, respectively, had identical PFGE patterns, suggesting that these are originated from identical clones. Against MRSA from patients, only vancomycin was the most active (MIC range < or =2 microg/ml), whereas the resistance rates were 35% to rifampin and 65% to mupirocin. The resistance rates of patient isolates were > or =90% to amikacin, clindamycin, ciprofloxacin, erythromycin, fusidic acid, gentamicin and tetracycline. In conclusion, the MRSA carriage rates of healthy hospital workers were relatively high, 2.3~7.7%, depending on groups. Family members of a few primary school children with MRSA showed a high carriage rate, suggesting that intrafamily transmission occurred. MRSAs isolated from dermatology inpatients were relatively more resistant to various antimicrobial agents, including mupirocin, but all isolates were susceptibility to vancomycin.
Amikacin ; Anti-Infective Agents ; Child ; Ciprofloxacin ; Clindamycin ; Clone Cells ; Coagulase ; Dermatology ; DNA ; Erythromycin ; Fusidic Acid ; Genotype ; Gentamicins ; Humans ; Inpatients ; Korea ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Mupirocin ; Rifampin ; Tetracycline ; Vancomycin ; Natural Resources

The objective of this study was to analyze quantitatively whether Weissella cibaria could affect the proliferation of five periodontopathic bacteria, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum, after incubation for 8~48 h. In addition, by using real-time PCR with a dual-labeled probe, each growth of bacteria was examined under different growth media conditions. The proliferation of periodontopathic bacteria was significantly inhibited by W. cibaria after incubation for 24~48 h (p < 0.05), whereas the growth of W. cibaria was not affected by these pathogenic bacteria. The growth of P. gingivalis, T. forsythia and T. denticola significantly increased in each growth media after incubation for 24 h (p < 0.05), as compared to the culture in mixed growth media. However, no differences in the growth of five periodontopathic bacteria were observed between each growth media and mixed media after incubation for 48 h. The growth and pH of W. cibaria culture significantly were changed in MRS after incubation for 24~48 h (p < 0.05), as compared to the bacterial culture in mixed growth media. The pH of P. gingivalis and F. nucleatum culture significantly was changed in both growth media and mixed media after incubation for 24~48 h (p < 0.05). Our data indicate that W. cibaria significantly inhibits the proliferation of five periodontopathic bacteria and each growth of bacteria is quantitatively analyzed under various media conditions by real-time PCR.
Bacteria ; Forsythia ; Fusobacterium nucleatum ; Hydrogen-Ion Concentration ; Porphyromonas gingivalis ; Real-Time Polymerase Chain Reaction ; Treponema denticola ; Weissella

All of the methicillin-resistant Staphylococcus aureus (MRSA) strains exhibit resistance to oxacillin by producing PBP2a encoded by mecA, whereas methicllin-susceptible Staphylococcus aureus (MSSA) strains do not. To investigate phenotypic differences other than oxacillin resistance level in responses to oxacillin between MSSA and MRSA, we compared alterations of viability and ultrastructure of MSSA by oxacillin treatment with those of MRSA. When MSSA and MRSA strains were exposed to oxacillin of their respective MICs, and then were assayed for viability and observed by transmission electron microscope, increase in thickness of cell wall was more prominent in MRSA strains than in MSSA strains, while decrease in number of surviving cells was more evident and change in morphology of growing cross wall was greater in MSSA strains than in MRSA strains. It is assumed that these different responses to oxacillin between MSSA and MRSA strains may be due to activation of some PBP2a unbound to oxacillin. In conclusion, MSSA and MRSA showed different functional and morphological responses to oxacillin, although they were treated with oxacillin of concentrations that respectively inhibit their proliferation.
Adenosine ; Cell Wall ; Electrons ; Methicillin-Resistant Staphylococcus aureus ; Oxacillin ; Staphylococcus aureus

This study examined the prevalence of oral microbes in the saliva of oncological patients and healthy subjects. PCR was used to assess the frequency of oral microbes including 3 cariogenic bacteria, 5 periodontopathic bacteria and 4 Candida species in the saliva of 104 oncological patients and 52 healthy subjects. Among these microorganims, Streptococcus mutans, Fusobacterium nucleatum and Candida albicans were most frequently detected in both groups. There were no significant differences in the prevalence of cariogenic bacteria between the patient and healthy groups, whereas significant differences in the frequency of Porphyromonas gingivalis and Tannerella forsythia were observed between the two groups (p < 0.05). The prevalence of all five periodontopathogens was higher in the healthy group than in the patient group. The prevalence of C. albicans in patients was significantly higher than that of healthy group (p < 0.05). In conclusion, there were significant differences in the prevalence of P. gingivalis, T. forsythia and C. albicans between the oncological patient group and healthy group.
Bacteria ; Candida ; Candida albicans ; Forsythia ; Fusobacterium nucleatum ; Humans ; Polymerase Chain Reaction ; Porphyromonas gingivalis ; Prevalence ; Saliva ; Streptococcus mutans

To find whether productivity of bacteriocin is controlled between different species under unusual cultural conditions, we used Rhodobacter capsulatus ATCC 17016 as a producer and Rhodopseudomonas palustris ATCC 17003 as an indicator. Rhodobacter capsulatus was cultured under aerobic conditions in the dark in Lascelles medium containing 0.3% Triton X-100. As a result, bacteriocin productivity increased enormously. The optimal pH range of bacteriocin production was 6~7.8. Through partial purification of bacteriocin, the molecular weight was roughly estimated at 14 kDa. Plasmid had no influence on bacteriocin production by Rhodobacter capsulatus. Our findings indicate that culture conditions affect bacteriocin productivity between more distantly related species, and bacteriocin of Rhodobacter capsulatus is not encoded by a plasmid.
Bacteria ; Efficiency ; Hydrogen-Ion Concentration ; Molecular Weight ; Octoxynol ; Plasmids ; Rhodobacter ; Rhodobacter capsulatus ; Rhodopseudomonas

A total of 1,395 Haemaphysalis longicornis ticks collected from Jeju Island of Korea were examined by 16S rRNA gene-based nested PCR for the presence of infection with Anaplasma and Ehrlichia species. Template DNAs to detect the tick-borne pathogens were prepared from a total 506 tick pools. Eight genera of Anaplasma and six Ehrlichia by 16S rRNA gene PCR and sequencing analysis were identified. A. phagocytophilum was the most prevalent (27 [1.9%]) by nested PCR, followed by A. bovis (5 [0.4%]), E. chaffeensis (4 [0.2%]), and A. centrale (1 [0.1%]). In the phylogenetic analysis based on 16S rRNA sequences, eight genera of Anaplasma group (> 99.4% homology) and six Ehrlichia group (> 99.5% homology) were close to deposited A. marginale strains (AF309867, AF414874, and FJ226454) and Ehrlichia sp. (DQ324547), respectively. Three Anaplasma species groups A. phagocytophilum (group A), A. bovis (group B), and A. centrale (group C) and one Ehrlichia species E. chaffeensis (group D) were determined by comparing with Anaplasma and Ehrlichia related sequences. First, twenty-eight A. phagocytophilum clones belonging to group A were divided into 7 genotypes. The sequence similarity among genotypes A1 to A4 was very high (> 99.6%). Genotype B2 was close to A. bovis from Korea (99.7%). Genotype D1 was close to known E. chaffeensis strains (M73222, AF147752, and AY350424) and their similarity value was 99.7%. In conclusion, the genera of Anaplasma/Ehrlichia, A. phagocytophilum, and E. chaffeensis identified in predominant H. longicornis ticks were ubiquitous throughout the Jeju Island. The various native groups have been found through sequence identities and phylogenetic analysis.
Anaplasma ; Anaplasma phagocytophilum ; Clone Cells ; DNA ; Ehrlichia ; Ehrlichia chaffeensis ; Genes, rRNA ; Genotype ; Korea ; Polymerase Chain Reaction ; Ticks

A total of 90 Acinetobacter isolates from freshwater and seawater in Gangjin Bay of Korea was investigated for the distribution of genomic species, antimicrobial resistance patterns and clonal relatedness. By amplified ribosomal DNA restriction analysis, eighty-nine Acinetobacter isolates were classified into 11 Acinetobacter genomic species. A. johnsonii (n=23) was the most prevalent, followed by A. baumannii (n=13), A. calcoaceticus (n=13), Acinetobacter genomic species 11 (n=10), A. phenon 6/ct13TU (n=9), A. junii (n=5), A. venetianus (n=5), Acinetobacter genomic species 17 (n=4), 14BJ (n=3), A. phenon 10/1271 (n=2), Acinetobacter genomic species 3 (n=1), and ungrouped (n=1). The majority of Acinetobacter genomic species were isolated from the site A and B, and some known nosocomial pathogens in the clinical environment were observed among them. Of the 11 antimicrobial drugs tested, several A. johnsonii isolates exhibited high-frequency resistance to a wide variety of antimicrobial agents, including ampicillin-sulbactam, piperacillin, ceftazidime, cefotaxime, and sulfamethoxazole (p < 0.001). Some Acinetobacter genomic species were resistant to currently used antibiotics but all isolates were susceptible to imipenem, amikacin, and tetracycline. Based on the results of antimicrobial resistance pattern and phylogenetic analysis, 23 A. johnsonii isolates were classified into 19 pulsotypes. In conclusion, there was a significant difference in the distribution of Acinetobacter species between freshwater and seawater. Predominance of A. johnsonii strains was probably due to their ability to proliferate in the contaminated aquatic environment originated from local geographic features. Therefore, the waste effluent from animals and humans plays an important role in the distribution of Acinetobacter species in aquatic environment.
Acinetobacter ; Amikacin ; Ampicillin ; Animals ; Anti-Bacterial Agents ; Anti-Infective Agents ; Bays ; Cefotaxime ; Ceftazidime ; DNA, Ribosomal ; Fresh Water ; Humans ; Imipenem ; Korea ; Piperacillin ; Seawater ; Sulbactam ; Sulfamethoxazole ; Tetracycline

Biofilms are well-organized, complex microbial communities that are often highly resistant to antimicrobial agents and host defenses. Biofilms are often formed on the surfaces of surgical implants and indwelling catheters. Being extremely resistant to removal, biofilms, once formed, cause numerous complications and often result in persistent infections that require long-term hospitalization for treatment. Until now, preventive measures employing prophylactic antimicrobials that prohibit or restrict biofilm formation have been the only feasible, effective options available, with the constant concomitant threat of antimicrobial resistance. However, the development of chemical agents that specifically act upon the virulence of biofilms, rather than destroying the microorganisms or suppressing their growth, is a promising new approach. Such agents are highly desirable in that they might allow clinicians to prevent the development of antimicrobial resistance. Effective suppression of biofilm formation would dramatically change the way to treat infectious disease. In this literature review, the types of infections associated with biofilms and relevant therapeutic options that have been approved, in use, or under development to treat biofilm infections are discussed, along with novel approaches to biofilm control that may be applicable to the development of future anti-biofilm agents.
Anti-Infective Agents ; Biofilms ; Catheters, Indwelling ; Communicable Diseases ; Diphtheria Toxoid ; Haemophilus Vaccines ; Hospitalization

No abstract available.
Base Sequence*

In this study, we examined the expression of Toll-like receptor3 (TLR3) by human retinal pigment epithelial cells (RPE) and determined whether exposure to the TLR3 agonist polyinosinic-polycytidylic acid (poly I:C) would induced the expression of cytokines in these cells. RT-PCR revealed that TLR3 was constitutively expressed in human RPE, and its expression was increased by treatment with poly I:C. After treatment with poly I:C, we determined the expression levels of pro-inflammatory cytokines in human RPE using RT-PCR and ELISA. We demonstrated that poly I:C treatment increased the production of TNF-alpha, IL-6, and IL-8 in human RPE. Upon exposure to poly I:C, human RPE initiated antiviral response resulting in the induction of IFN-beta mRNA expression and 2',5'-oligoadenylate synthetase mRNA expression. These results suggest that human RPE may participate in ocular defense mechanism against viral infection through TLR3.
2',5'-Oligoadenylate Synthetase ; Cytokines* ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells* ; Humans* ; Interferons ; Interleukin-6 ; Interleukin-8 ; Poly I-C ; Retinal Pigment Epithelium ; Retinaldehyde* ; RNA, Messenger ; Tumor Necrosis Factor-alpha