Comparison of genetic epidemiology of vancomycin-resistant Enterococcus faecium isolates from humans and poultry.

This study was conducted to investigate the molecular characteristics and genetic relatedness of vancomycin-resistant Enterococcus faecium (VREF) isolates obtained from humans and poultry in Korea. A total of 147 VREF isolates from humans (71 clinical isolates) and poultry (76 isolates) in Korea were compared with respect to their antibiotic susceptibilities, organization of the Tn1546 transposon element, detection of virulence genes (esp and hyl), pulsed-field gel electrophoresis (PFGE) typing and multilocus sequence typing (MLST). All of the human and poultry isolates had the vanA gene and 11.

Epidemics of viral meningitis caused by echovirus 6 and 30 in Korea in 2008.

Background: Enteroviruses (EVs) are the leading cause of aseptic meningitis, which is the most frequent central nervous system infection worldwide. We aimed to characterize the EVs involved in an aseptic meningitis outbreak in Korea in 2008. In Korea, Echovirus type 30 (E30) and E6 have been associated with outbreaks and frequent meningitis.

Hepatitis B vaccination and liver cancer mortality reduction in Korean children and adolescents.

Liver cancer is one of the three most common causes of cancer mortality in the world and it is closely related to chronic hepatitis B viral (HBV) infection in Korea. The decline of HBV prevalence for the last two decades in Korea might be partly due to the HBV vaccination, which was implemented as a national program starting in 1995. The aim of this study was to assess the period effect of the national HBV vaccination on liver cancer mortality in a young population.

Clustering of Mycobacterium tuberculosis strains from foreign-born patients in Korea.

Information on drug resistance and transmission patterns of tuberculosis (TB) in foreign-born patients is lacking in Asia where immigration is increasing. We examined the drug-resistance profiles of 288 Mycobacterium tuberculosis isolates from foreign-born patients in South Korea, and assessed for potential transmission in the host country by analysing their IS6110 genotypes, as well as those of 4780 strains from native Korean TB patients. The prevalence of multidrug-resistant (MDR) TB was 9.

Development of a highly sensitive real-time one step RT-PCR combined complementary locked primer technology and conjugated minor groove binder probe.

Background: Enterovirus (EV) infections are commonly associated with encephalitis and meningitis. Detection of enteroviral RNA in clinical specimens has been demonstrated to improve the management of patients, by ruling out other causes of disease.

Method: To develop a sensitive and reliable assay for routine laboratory diagnosis, we developed a real-time one step reverse transcription polymerase chain reaction (RT-PCR) assay with minor groove binder probes and primers modified with complementary locked primer technology (TMC-PCR).

Epidemics of enterovirus infection in Chungnam Korea, 2008 and 2009.

Previously, we explored the epidemic pattern and molecular characterization of enteroviruses isolated in Chungnam, Korea from 2005 to 2006. The present study extended these observations to 2008 and 2009. In this study, enteroviruses showed similar seasonal prevalent pattern from summer to fall and age distribution to previous investigation.

Mitogen-activated protein kinase kinase 1 (MEK1) stabilizes MyoD through direct phosphorylation at tyrosine 156 during myogenic differentiation.

Previously, we reported that mitogen-activated protein kinase kinase 1 (MEK1) activated in the mid-stage of skeletal muscle differentiation promotes myogenic differentiation. To elucidate the molecular mechanism, we investigated an activity of MEK1 for MyoD. Activated MEK1 associates with MyoD in the nucleus of differentiating myoblasts.

In vitro biofilm formation and bactericidal activities of methicillin-resistant Staphylococcus aureus clones prevalent in Korea.

The purpose of this study was to quantify the biofilm formations of various methicillin-resistant Staphylococcus aureus (MRSA) clones (ST1, ST5, ST72, ST89, ST239, and ST254) and to evaluate the in vitro activities of antibiotics. Of 86 MRSA isolates tested, 44 isolates (51.2 %) formed biofilms, including 8 strong biofilm producers (7 isolates of ST72 and 1 isolate of ST89).

Molecular cloning of Plasmodium vivax calcium-dependent protein kinase 4.

A family of calcium-dependent protein kinases (CDPKs) is a unique enzyme which plays crucial roles in intracellular calcium signaling in plants, algae, and protozoa. CDPKs of malaria parasites are known to be key regulators for stage-specific cellular responses to calcium, a widespread secondary messenger that controls the progression of the parasite. In our study, we identified a gene encoding Plasmodium vivax CDPK4 (PvCDPK4) and characterized its molecular property and cellular localization.

Study of the genetic discrimination between imported and autochthonous cases of malaria in South Korea.

There has been a great increase of Plasmodium vivax incidences in the Republic of Korea and the genetic diversity of the parasite became more complex with the rapid dissemination of newly introduced genotypes. Surveillance of imported malaria is very important, but there is no good way to determine imported vs. internal cases.

An aminopeptidase from Streptomyces sp. KK565 degrades beta amyloid monomers, oligomers and fibrils.

The accumulation of beta amyloid (Aβ) has been a primary target for Alzheimer disease therapeutic strategies. Previously, we discovered an activity from Streptomyces sp. KK565 growth media that inhibits Aβ aggregation.

Glutamate carboxypeptidase II: an amyloid peptide-degrading enzyme with physiological function in the brain.

Proteolytic processing of amyloid peptides (Aβs) is one important mechanism that controls the brain Aβ level. Although several Aβ-degrading enzymes were identified, evidence has suggested the presence of other peptidases. Here, we report a novel function of glutamate carboxypeptidase II (GCPII) in Aβ degradation in brain, which is a peptidase involved in N-acetylaspartylglutamate cleavage, folate metabolism, and prostate tumorigenesis.

Seasonal prevalence of asymptomatic norovirus infection in Korean children.

The prevalence of asymptomatic norovirus (NoV) infection was investigated in children registered for kindergarten in Korea during the winter and summer. Children with no gastrointestinal symptoms, including diarrhea and abdominal pain, during the 2 weeks before and following sample collection were included in this investigation. NoV presence and genetic identification were determined with real-time reverse transcriptase-polymerase chain reaction and conventional nested reverse transcriptase-polymerase chain reaction.

Clinical and etiological characteristics of enterovirus 71-related diseases during a recent 2-year period in Korea.

Human enterovirus 71 (EV 71) has caused large-scale outbreaks of hand-foot-and-mouth disease (HFMD), particularly in the Asian-Pacific region. In this study, we report a major outbreak of EV 71 infection in Korea and describe the clinical differences between EV 71 and non-EV 71 enterovirus infections. We prospectively enrolled patients with suspected viral infections during a recent 2-year period through a nationwide surveillance system.

Identification of type 2 diabetes-associated combination of SNPs using support vector machine.

Background: Type 2 diabetes mellitus (T2D), a metabolic disorder characterized by insulin resistance and relative insulin deficiency, is a complex disease of major public health importance. Its incidence is rapidly increasing in the developed countries. Complex diseases are caused by interactions between multiple genes and environmental factors.

Two-step maturation of immature DCs with proinflammatory cytokine cocktail and poly(I:C) enhances migratory and T cell stimulatory capacity.

Effective induction of cell-mediated immune responses strongly depends on the ability of dendritic cells (DCs) to produce Th1-polarizing cytokines, migrate to lymph nodes and stimulate T cells through antigen-presenting complex and costimulatory molecules. While various protocols for optimizing DC maturation with single or multiple stimuli mimicking infections or inflammatory milieu have been proposed for the generation of DCs with features desired for clinical application, stepwise maturation of DCs by these multiple stimuli has not been systemically assessed. Among the combinations of several immune-modulating factors with known effects on DC maturation, we found that stepwise DC maturation with cytokine cocktail (TNF-alpha+IL-6+IL-1 beta+PGE(2)) followed by poly(I:C) stimulation enhanced the production of IL-12 with strong allostimulatory capacity.

Genotype of Toxoplasma gondii from blood of stray cats in Gyeonggi-do, Korea.

Genotyping of Toxoplasma gondii has been performed in 23 PCR positive blood samples from stray cats in Korea. We used 2 separate PCR-restriction fragment length polymorphism (RFLP) patterns of SAG2 gene, amplifying the 5' and 3' ends of the locus. The results revealed that all samples belonged to the type I clonal lineage.

MEK1 plays contrary stage-specific roles in skeletal myogenic differentiation.

The role of extracellular signal-regulated kinase (ERK) signaling in skeletal myogenesis has been reported to be both stimulatory and inhibitory. We propose that this discrepancy may arise from the stage-specific, different roles of mitogen-activated protein kinase kinase 1 (MEK1). We found that the phosphorylated MEK1 level of differentiating C2C12 cells was low on day 1 (early-stage) and reached a maximum on days 2-3 (mid-stage).

Sustained viral activity of epstein-Barr virus contributes to cellular immortalization of lymphoblastoid cell lines.

EBV-transformed lymphoblastoid cell lines (LCLs) are used as a resource for human genetic, immunological, and pharmacogenomic studies. We investigated the biological activity of 20 LCL strains during continuous long-term subculture up to a passage number of 160. Out of 20 LCL strains, 17 proliferated up to a passage number of 160, at which point LCLs are generally considered as "immortalized".

Prevalence of Toxoplasma gondii in stray cats of Gyeonggi-do, Korea.

Toxoplasma gondii is an obligate intracellular zoonotic protozoan with a worldwide distribution. It infects humans as well as a broad spectrum of vertebrate hosts. Cats and wild felidae play crucial roles in the epidemiology of toxoplasmosis.

New predictive equations for spirometric reference values and comparison with Morris equation in a Korean population.

Background And Objective: The clinical importance of the differences between actual and predicted spirometric indices in non-Western populations is poorly defined. This study evaluated the differences between the spirometric values derived from Morris equation, traditionally used in South Korea, and the actual values, in the classification and detection of patients with respiratory diseases, and developed new predictive equations for the calculation of reference spirometric values for healthy Koreans.

Methods: Data derived from a subset of the population who completed the initial baseline survey of the Korean Health and Genome Study were used to develop new predictive equations for spirometric reference values, using multiple linear regression.

Development of real-time PCR assays for detection and quantification of human bocavirus.

Background: Human bocavirus (HBoV) is a parvovirus that has been recently detected in patients with respiratory illness.

Objectives: We developed a sensitive, specific, and quantitative real-time PCR assay based on the TaqMan method for HBoV detection and quantification in respiratory specimens.

Study Design: Three individual real-time PCR assays were designed to amplify HBoV NS1, NP-1, and VP1 genes.

Five-year report of national surveillance of antimicrobial resistance in Pseudomonas aeruginosa isolated from non-tertiary care hospitals in Korea (2002-2006).

A nationwide surveillance of the antimicrobial resistance of Pseudomonas aeruginosa isolates from non-tertiary care hospitals was conducted in Korea from 2002 to 2006. Resistance to almost all antimicrobial agents decreased significantly from 2003 (P < 0.01).

Anopheles kleini, Anopheles pullus, and Anopheles sinensis: potential vectors of Plasmodium vivax in the Republic of Korea.

Anopheles sinensis Wiedemann (63.3%) was the most abundant Anopheles mosquito captured at cowshed resting collections in malaria high-risk areas (northern Gyeonggi Province) near the demilitarized zone (DMZ) in Korea during 2005, followed by Anopheles kleini Rueda (24.7%) and Anopheles pullus M.

Universal and mutation-resistant anti-enteroviral activity: potency of small interfering RNA complementary to the conserved cis-acting replication element within the enterovirus coding region.

The promising potential of RNA interference-based antiviral therapies has been well established. However, the antiviral efficacy is largely limited by genomic diversity and genetic instability of various viruses, including human enterovirus B (HEB). In this work, the first evidence supporting the anti-HEB activity of the small interfering RNA (siRNA) targeting the highly conserved cis-acting replication element (CRE) within virus coding region 2C is presented.