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This study aims to investigate the effect of electronic stimulation (ES) as a non-pharmacological treatment in restless legs syndrome (RLS). This is a randomized, single-blind study. A total of 46 patients were included, consisting of an active group and a sham group with 22 and 24 members, respectively. The stimulation was administered to bilateral lower legs using the tapping mode (3 Hz) on a handheld ES device, and symptom changes were measured in both groups. The effects of the stimuli were analyzed with repeated measures ANOVA. The symptom severity was significantly reduced in the active group, and showed significant interaction effects in the time * group (F = 4.441, p = 0.031). Although both the active and sham groups reported improved symptoms upon receiving longer periods of treatment, the effect of the ES was greater in the active group. ES treatment resulted in symptom improvement when using ideal levels of stimulation intensity. ES can be considered as a non-pharmacological treatment option for RLS. [ABSTRACT FROM AUTHOR]

Background and purpose: Restless legs syndrome (RLS) is a neurological disorder which is most commonly identified by an urge to move the legs. It often shows alterations in sensory processing which implies the salience network (SN) is experiencing changes. This study investigates the functional connectivity (FC) between the SN and other areas of the brain in RLS patients during the resting state period. Methods: Thirty patients with drug naïve idiopathic RLS and 30 healthy age and gender matched controls were included in this study. Resting state fMRIs were performed in the morning during the asymptomatic period. The SN comparisons were conducted between the two groups. Results: The RLS group showed a reduction in SN FC in the right pyramis, and an increase in SN FC in the bilateral orbitofrontal gyri and right postcentral gyrus. Conclusions: The results of this study give reason to believe that SN FC in RLS patients is altered during asymptomatic periods. This could have an influence on the processing of the saliency of information, particularly sensory information processing and inhibition mechanisms. [ABSTRACT FROM AUTHOR]

Objectives: Resting-state brain connectivity has been shown to differ for Restless Legs Syndrome (RLS) compared to healthy control (CON) groups. This study evaluates the degree these RLS-CON differences are changed by concurrent treatment.Methods: Resting-state functional MRIs were obtained from 32 idiopathic RLS patients during the morning asymptomatic period and 16 age and gender-matched CON subjects. Of the 32 RLS patients, 16 were drug-naïve (DN-RLS), and 16 were regularly drug-treated using a dopamine agonist (DT-RLS). Various assessments of disease characteristics were also performed. The primary purpose was to assess the replicability of prior results and the effects of treatment on these differences between controls and untreated RLS patients. Resting-state connectivity was analyzed by a seed-based method using the bilateral ventral-posterolateral nuclei (VPLN) in the thalamus.Results: In the DN-RLS group, compared to the CON group, three areas (the bilateral lingual gyri and right middle temporal gyrus) were replicated. The three replicated areas did not significantly differ for DT-RLS compared to DN-RLS. DT-RLS compared to DN-RLS had significantly higher thalamic connectivity for the left uvula, right tuber, left anterior insula, and right declive.Conclusions: Thalamic connectivity to the bilateral lingual gyri and right middle temporal gyrus is a replicable finding in DN-RLS that was not affected by dopamine agonist treatments. Other changes in thalamic connectivity were altered by dopamine agonist treatment. These treatment effects may be pertinent to the known treatment benefits of a dopamine agonist on RLS symptoms. [ABSTRACT FROM AUTHOR]

Objective: Restless legs syndrome (RLS) patients compared to controls have been found to have abnormal patterns in the default mode network (DMN) in the morning when symptom threshold is the highest and symptoms are least likely to occur. If these morning abnormalities in DMN are pertinent to disease expression, then similar or further detectable differences may be expected on a nighttime assessment when RLS symptom threshold is at its lowest. The purpose of this study was to elucidate the potential neural mechanisms underlying the circadian aspect of RLS symptom expression by assessing diurnal changes in DMN.Methods: Fifteen drug-naïve subjects with idiopathic RLS and 15 age- and gender-matched healthy subjects had fMRI scans in the morning and evening. The DMN patterns were compared both for differences between morning and evening and between RLS and controls.Results: RLS patients compared to the healthy controls showed significant differences in morning and evening DMN. In particular, RLS patients showed consistent increased connectivity in the parietal lobule in both the morning and evening. In contrast, connectivity in the thalamus was increased in the morning and reduced in the evening. In addition, there were negative correlations between thalamic connectivity and the Korean versions of the international RLS scale and the quality-of-life subscore.Conclusions: The results indicated diurnal disturbances of the DMN in RLS subjects are consistent with both the circadian rhythm and severity of RLS. The circadian expression of RLS may relate to changes in arousal cortical-activation thresholds occurring with diurnal changes in the thalamic circuits of the DMN. [ABSTRACT FROM AUTHOR]

Background: The unusual sensations of restless legs syndrome/Willis-Ekbom disease (RLS/WED) are induced by rest or a low arousal state with a circadian variation in the threshold for induction. It has been suggested that the emergence of RLS/WED symptoms relates to abnormal brain functions dealing with internally generated stimuli. The purpose of this study was to investigate the changes in the default mode network (DMN) in RLS/WED subjects.Methods: Sixteen drug-naïve, idiopathic, RLS/WED subjects, and 16 age-matched and gender-matched healthy subjects were scanned in an asymptomatic resting state. A comparison of the DMN was conducted between the two groups. Resting state functional magnetic resonance imaging (MRI), Korean versions of the International RLS scale, and other sleep questionnaires were used.Results: The results showed reductions in the DMN connectivity in the left posterior cingulate cortex, the right orbito-frontal gyrus, the left precuneus, and the right subcallosal gyrus of the RLS/WED subjects. The DMN connectivity was increased in sensory-motor-associated circuits, which included the right superior parietal lobule, the right supplementary motor area, and the left thalamus. In addition, the connectivity between the DMN and thalamus was negatively correlated with that in the orbito-frontal gyrus and the subcallosal gyrus in the subjects.Conclusions: The results showed disturbances of the DMN in RLS/WED subjects that influence the thalamic relay sensory-motor-associated circuit. These findings may underscore the fact that RLS/WED subjects have disturbances in default mode network functions involving internal stimuli in the resting state. This may be related to compensatory changes to maintain resting. [ABSTRACT FROM AUTHOR]

Abstract: The presence of fluoroquinolone resistance-associated alterations in topoisomerase II and IV were investigated for 103 nfxC-like type Pseudomonas aeruginosa isolates. The most nfxC-like type isolates (98.1%) possessed the substitution of Ile for Thr-83 in GyrA. A single alteration in GyrA (Thr-83→Ile) was the most frequently detected and the next common alteration was two alterations with Thr-83→Ile in GyrA and Ser-87→Leu in ParC. A novel alteration at position Glin-106 of GyrA, which was suggested to be responsible for fluoroquinolone resistance, was identified. Our study revealed that the alterations in GyrB (Glu-468→Asp) and in ParE (Asp-419→Asn or Glu-459→Asp) play a complementary role in the acquisition of resistance to fluoroquinolone. There was a correlation between the ciprofloxacin MIC and the number of resistance-associated alterations in GyrA, GyrB, ParC and ParE of P. aeruginosa isolates. [Copyright &y& Elsevier]

Of 18 vanA -positive vancomycin-susceptible Enterococcus faecium isolates, vanRS in the vanA cluster was detected in all isolates, while vanHAX was detected in only 2 isolates. Following exposure to glycopeptides, 22.2% of vancomycin-susceptible E . faecium (VSE) converted into vancomycin-resistant E . faecium . The vanA cluster of the revertant mutant was transferred to the VSE isolates. [ABSTRACT FROM AUTHOR]

Background: Rabies is a major public health problem with a fatality rate close to 100%; however, complete prevention can be achieved through pre- or post-exposure prophylaxis. The rapid fluorescent focus inhibition test (RFFIT) is one of the recommended testing methods to determine the production of neutralizing antibodies after vaccination. Here, we report the development of a new monoclonal antibody (mAb) designed to react specifically with Rabies virus (RABV) phosphoprotein (P protein), and the evaluation of its applicability to the RFFIT and its effectiveness as a diagnostic reagent for human rabies. Methodology/principal findings: The mAb KGH P 16B8 was produced to target the P protein of the Korean KGH RABV strain. An indirect immunofluorescence assay (IFA) was conducted to detect various strains of RABV in various cell lines. Alexa-conjugated KGH P 16B8 (16B8-Alexa) was developed for the RFFIT. The IFA test could detect RABV up to a 1:2,500 dilution, with a detection limit comparable to that of a commercial diagnostic reagent. The sensitivity, specificity, positive predictive value, and negative predictive value of the RFFIT using 16B8-Alexa in 414 clinical specimens were 98.67%, 99.47%, 99.55%, and 98.42%, respectively. The results of the RFFIT with 16B8-Alexa were strongly correlated with those obtained using an existing commercial diagnostic reagent (r = 0.995, p<0.001). Conclusions/significance: The mAb developed in this study shows high sensitivity and specificity, confirming its clinical utility with the RFFIT to measure the rabies neutralizing antibody titer and establish a diagnosis in human. Thus, 16B8-Alexa is expected to serve as an alternative diagnostic reagent that is widely accessible, with potentially broad applications beyond those of the RFFIT in Korea. Further studies with 16B8-Alexa should provide insight into the immunological mechanism of the P protein of Korean RABV. [ABSTRACT FROM AUTHOR]

Objective: Previous studies have suggested that early-onset RLS (EOR) and late-onset RLS (LOR) might have different etiopathophysiologies. Few previous studies have examined accumulation of cerebrovascular ischemic changes as a potential cause of LOR.Methods: We recruited 39 RLS subjects (LOR: defined as age of RLS onset ≥45, n = 18 and EOR: age of onset <45; n = 21); and 39 healthy control subjects matched on age and sex. Structural magnetic resonance imaging (MRI) of the brain was performed for each subject, and images were graded for severity of periventricular white matter hyperintensities (PVH) and deep white matter hyperintensities (DWMH) independently by trained raters according to standardized methods.Results: Interrater reliabilities were 0.861 (p <0.001) for PVH and 0.900 (p <0.001) for DWMH. LOR subjects had a significantly higher grade of DWMH than the EOR subjects (p = 0.043) and age- and sex-matched controls (p = 0.015). In contrast, there was no difference in DWMH severity rating between the EOR group and the EC group or in PVH severity between the LOR or EOR groups and their age-matched controls.Conclusion: Our findings suggest that the presence and severity of DWMH is associated with LOR, but not with EOR. Further examination of the contribution of cerebrovascular disease to the etiopathogenesis of LOR is warranted. [ABSTRACT FROM AUTHOR]

Abstract: Background: Restless legs syndrome (RLS) is a primary sensory disorder with a secondary motor component (e.g., urge to move), and the thalamus is known to play a central role in RLS. The purpose of our study was to explore the intrinsic changes in the thalamocortical circuit in RLS patients using a resting-state functional magnetic resonance imaging (fMRI) paradigm. Methods: Resting-state fMRIs were obtained in the morning from 25 idiopathic RLS patients who were not using RLS medications and 25 controls. Resting-state connectivity was analyzed by a seed-based method using Analysis of Functional NeuroImages (AFNI) software with the bilateral thalami (ventroposterolateral nucleus [VPLN]). The connectivity characteristics of RLS patients were compared to those of the controls. Results: We found that RLS patients showed reduced thalamic connectivity with the right parahippocampal gyrus, right precuneus, right precentral gyrus, and bilateral lingual gyri; however, the right superior temporal gyrus, bilateral middle temporal gyrus, and right medial frontal gyrus showed enhanced connectivity with the thalamus. RLS severity was negatively correlated with connectivity between the thalamus and right parahippocampal gyrus (r =−0.414; P =.040). Conclusions: Our results suggest that the characteristics of the connectivity changes may reflect the pathways involved in producing RLS symptoms and indicate that RLS patients may have deficits in controlling and managing sensory information, which supports the act of viewing RLS as a disorder disrupting somatosensory processing. [Copyright &y& Elsevier]

Abstract: 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). The planktonic MICs, minimal bactericidal concentrations, and minimum biofilm eradication concentrations (MBECs) of 6 antibiotics (clindamycin, gentamicin, linezolid, vancomycin, daptomycin, and tigecycline) were measured for 8 MRSA isolates. The planktonic isolates were susceptible to all agents, with daptomycin being the most effective, followed by gentamicin and vancomycin. However, clindamycin, linezolid, and tigecycline showed bacteriostatic activity against most of the isolates. The biofilms were resistant to high concentrations of most drugs. However, the MBEC values of daptomycin and tigecycline were lower overall than that of other antibiotics. Microscopy studies verified that daptomycin was the most effective drug used in adhesive biofilms, while gentamicin and tigecycline exhibited some bactericidal efficacy. Our results demonstrated that ST72 and ST89 form strong biofilms that may cause problems in hospital setting, and daptomycin, gentamicin, and tigecycline may be choice therapeutics against biofilm-mediated S. aureus infections. [Copyright &y& Elsevier]

Background: The number of human Q fever cases in South Korea has been rapidly increasing since 2015. We report the first isolation of Coxiella burnetii in Korea in two patients who initially presented with non-specific febrile illness and were finally diagnosed with acute Q fever in South Korea.Case Presentation: Two adult patients with fever had serologic tests against C. burnetii initially negative, and polymerase chain reaction against 16S rRNA using whole blood was also negative. After bacterial amplification of C. burnetii in immune-depressed mice, we isolated C. burnetii from patients with acute Q fever. The isolates KZQ2 and KZQ3 were confirmed by polymerase chain reaction, nucleotide sequence analysis, and morphologic observation using a transmission electron microscope.Conclusions: These results can help us understand the clinical and epidemiologic features of Q fever in South Korea. [ABSTRACT FROM AUTHOR]

Prion propagation is mediated by the structural alteration of normal prion protein (PrPC) to generate pathogenic prion protein (PrPSc). To date, compounds for the inhibition of prion propagation have mainly been screened using PrPSc-infected cells. Real time–quaking-induced conversion (RT-QuIC) is one alternative screening method. In this study, we assessed the propagation inhibition effects of known anti-prion compounds using RT-QuIC and compared the results with those from a PrPSc-infected cell assay. Compounds were applied to RT-QuIC reactions at 0 h or 22 h after prion propagation to determine whether they inhibited propagation or reduced amplified aggregates. RT-QuIC reactions in presence of acridine, dextran sulfate sodium (DSS), and tannic acid inhibited seeded aggregation with sporadic Creutzfeldt-Jakob disease at 0 h. After treatment at 22 h, amplified fluorescence was decreased in wells treated with either acridine or tannic acid. Compound activities were verified by western blot of RT-QuIC products and in a dye-independent conversion assay, the Multimer Detection System. Protease K-resistant PrPSc fragments (PrPres) were reduced by DSS and tannic acid in the PrPSc-infected cell assay. Importantly, these inhibitory effects were similar despite different treatment times (0 h versus 3 days). Consequentially, RT-QuIC enabled the more specific classification of compounds according to action (i.e., inhibition of prion propagation versus reduction of amplified aggregates). RT-QuIC addresses the limitations of cell-based screening methods and can be used to further aid our understanding of the mechanisms of action of anti-prion compounds. [ABSTRACT FROM AUTHOR]

Most reverse genetic (RG) systems for rabies viruses (RVs) have been constructed on the genome background of laboratory-adapted strains. In this study, we developed an RG system using a Korean wild type (KGH) strain to investigate the pathogenic potential of different strains. We developed a RG system with the KGH strain for the first time. Following the complete genome sequencing of the KGH strain, pKGH infectious clones were constructed using the CMV/T7 promoter, and HamRz and HdvRz were introduced to allow self-cleavage of the synthesized RNA. We successfully recovered the rescued virus by constructing chimeric RVs in which we replaced a part of the construct with the partial gene from the fixed RC-HL strain. The rescued viruses formed clearer and countable plaques in an immunostaining plaque assay, with a distinct plaque morphology. Furthermore, compared with the chimeric RVs, the pKGH/RCinsΔ4 strain containing the KGH strain G protein exhibited a decreased efficiency of cell-to-cell spreading in BHK-21 cells and significantly reduced (100–1000 fold) replication kinetics. However, pKGH/RCinsΔ4 strain-infected mice revealed 100% morbidity at 11 days post-infection, whereas other chimeric RV strains showed no mortality. Our RG system is a useful tool for studying differences in the cell-to-cell spreading efficiency and replication with respect to the different internalization patterns of street and fixed laboratory-adapted viruses. [ABSTRACT FROM AUTHOR]

Inherited prion diseases (IPDs), including genetic Creutzfeldt-Jakob disease (gCJD), account for 10–15% of cases of prion diseases and are associated with several pathogenic mutations, including P102L, V180I, and E200K, in the prion protein gene (PRNP). The valine to isoleucine substitution at codon 180 (V180I) of PRNP is the most common pathogenic mutation causing gCJD in East Asian patients. In this study, we conducted follow-up analyses to identify candidate factors and their associations with disease onset. Whole-genome sequencing (WGS) data of five gCJD patients with V180I mutation and 145 healthy individuals were used to identify genomic differences. A total of 18,648,850 candidate variants were observed in only the patient group, 29 of them were validated as variants. Four of these validated variants were nonsense mutations, six were observed in genes directly or indirectly related to neurodegenerative disorders (NDs), such as LPA, LRRK2, and FGF20. More than half of validated variants were categorized in Gene Ontology (GO) terms of binding and/or catalytic activity. Moreover, we found differential genome variants in gCJD patients with V180I mutation, including one uniquely surviving 10 years after diagnosis of the disease. Elucidation of the relationships between gCJD and Alzheimer’s disease or Parkinson’s disease at the genomic level will facilitate further advances in our understanding of the specific mechanisms mediating the pathogenesis of NDs and gold standard therapies for NDs. [ABSTRACT FROM AUTHOR]

The fluorescent antibody test (FAT) is the most commonly used method for detection of the rabies virus (RV). The plaque assay can only be applied to fixed RVs, and cannot be used for street RVs. In this study, plaque formation allowing the determination of both fixed and street RVs was achieved using the immune plaque assay. The immune plaque assay carried out using both fixed and street RVs showed the formation of clear and countable plaques after immunostaining with anti-RV P monoclonal antibody and HRP-conjugated anti-mouse IgG. Plaque size increased with incubation time, and the plaque morphology differed according to viral strain. Fixed RVs had the dot-shaped regular plaque morphology and street RVs had the small irregular-shape plaque morphology. In addition, no significant differences were observed between the growth kinetics of the KGH strain when the virus was titrated using the FAT and the immune plaque assay. It allowed the successful detection and quantification of both street and fixed RVs through the production of clear, countable plaques, making it easy to obtain objective results. The assay is an applicable tool for the detection of RVs in various investigations, including virus neutralizing antibody testing, cell-to-cell spread, and viral drug sensitivity testing. [ABSTRACT FROM AUTHOR]

Successful empirical therapy of Staphylococcus aureus infections requires the ability to predict methicillin resistance. Our aim was to identify predictors of methicillin resistance in community-onset (CO) invasive S. aureus infections. Sixteen hospitals across Korea participated in this study from May to December 2012. We prospectively included cases of S. aureus infection in which S. aureus was isolated from sterile clinical specimens ≤72 hours after hospitalization. Clinical and epidemiological data were gathered and compared in methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) cases. Community-associated (CA) infections were defined as in previous studies. In total, there were 786 cases of community-onset S. aureus infection, 102 (13.0%) of which were CA-MRSA. In addition to known risk factors, exposure to 3rd generation cephalosporins in the past 6 months [odds ratio (OR), 1.922; 95% confidence interval (CI), 1.176–3.142] and close contact with chronically ill patients in the past month (OR, 2.647; 95% CI, 1.189–5.891) were independent risk factors for MRSA infection. However, no clinical predictors of CA-MRSA were identified. Methicillin resistance, CO infection, and appropriateness of empirical antibiotics were not significantly related to 30-day mortality. MRSA infection should be suspected in patients recently exposed to 3rd generation cephalosporins or chronically-ill patients. There were no reliable predictors of CA-MRSA infection, and mortality was not affected by methicillin resistance. [ABSTRACT FROM AUTHOR]

Abstract: In order to characterize molecular mechanisms of first- and second-line drug resistance in Mycobacterium tuberculosis and to evaluate the use of molecular markers of resistance, we analyzed 62 multidrug-resistant, 100 extensively drug-resistant, and 30 pan-susceptible isolates from Korean tuberculosis patients. Twelve genome regions associated with drug resistance, including katG, ahpC, and inhA promoter for isoniazid (INH); embB for ethambutol (EMB), rpoB for rifampin (RIF), pncA for pyrazinamide (PZA), gyrA for fluoroquinolones; rpsL, gidB, and rrs for streptomycin; rrs and eis for kanamycin (KM); rrs and tylA for capreomycin (CAP); and rrs for amikacin (AMK) were amplified simultaneously by polymerase chain reaction, and the DNA sequences were determined. We found mutations in 140 of 160 INH-resistant isolates (87.5%), 159 of 162 RIF-resistant isolates (98.15%), 127 of 143 EMB-resistant isolates (88.8%), 108 of 123 ofloxacin-resistant isolates (87.8%), and 107 of 122 PZA-resistant isolates (87.7%); 43 of 51 STM-resistant isolates (84.3%), 15 of 17 KM-resistant isolates (88.2%), and 14 of 15 (AMK and CAP)-resistant isolates (93.3%) had mutations related to specific drug resistance. In addition, the sequence analyses of the study revealed many novel mutations involving these loci. This result suggests that mutations in the rpoB531, katGSer315Thr, and C-15T in the inhA promoter region, and gyrA94, embB306, pncA159, rpsL43, and A1401G in the rrs gene could serve as useful markers for rapid detection of resistance profile in the clinical isolates of M. tuberculosis in Korea, with potentials for the new therapeutic benefits in actual clinical practice. [Copyright &y& Elsevier]

Abstract: The present study aimed to describe the prevalence and molecular epidemiology of metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa isolates obtained from non-tertiary care hospitals and geriatric hospitals in South Korea. Of the 644 isolates, 224 were carbapenem-resistant, amongst which 41 (18.3%) were MBL-producers and the major MBL type was IMP-6 (35 isolates). IMP-6-producing isolates were multidrug-resistant and showed higher minimum inhibitory concentrations for meropenem than imipenem. All of the IMP-6-producing isolates had class 1 integrons with amplification sizes of 4.5kb/5.5kb (34 isolates) or 3.0kb (1 isolate); 4.5kb/5.5kb integrons had bla IMP-6–qac–aacA4–bla OXA-1–aadA1 (5.5kb) and aadB–cmlA–bla OXA-10–aadA1 (4.5kb). Pulsed-field gel electrophoresis (PFGE) analysis indicated that all IMP-6-producing P. aeruginosa from various geographic areas had nearly identical patterns with >85% similarity. All IMP-6-producing isolates showed high genetic similarity to those obtained from tertiary care hospitals and had the same integron type, indicating the spread of these strains to the three types of hospitals nationwide. These data show the wide spreading of clonally related IMP-6-producing P. aeruginosa (sequence type235) through tertiary, non-tertiary and geriatric hospitals in South Korea. Continuous monitoring and thorough infection control should be performed in all types of hospitals to prevent further spreading of MBL-producing P. aeruginosa. [Copyright &y& Elsevier]

PCR fingerprinting and multilocus sequence typing were applied to determine the major molecular types of the Cryptococcus neoformans/ Cryptococcus gattii species complex in the Republic of Korea. Of the 78 strains isolated from patients diagnosed with cryptococcosis between 1990 and 2008, 96% were C. neoformans serotype A, mating type MATα and molecular type VNI. The remaining 4% were C. gattii, serotype B, mating type MATα and either molecular type VGIIb or VGIII. Of the 62 strains with known HIV status, only 14 (22.6%) were isolated from HIV-positive patients and belonged to molecular type VNI. Remarkably, 93% of the C. neoformans isolates had identical PCR fingerprint profiles with the VNIc genotype that has been identified recently as the major genotype among C. neoformans strains in China. Most strains (81.8%) of the VNIc genotype were associated with non-HIV patients compared with strains of the non-VNIc genotype (20%) ( P=0.009). Unlike the Chinese strains, a majority (60%) of the non-HIV patients infected with strains of the VNIc genotype in the Republic of Korea had serious underlying conditions, with cancer and liver disease being the most common. This study affirms VNIc to be the most prevalent genotype of C. neoformans isolated from non-HIV patients with cryptococcosis. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to investigate for the first time the prevalence and types of extended-spectrum β-lactamase (ESBL) and plasmid-mediated AmpC β-lactamase (PABL) in Enterobacteriaceae in Korean long-term care facilities (LTCFs). ESBL rates were 45.3% (72/159) in Escherichia coli and 42.7% (50/117) in Klebsiella pneumoniae. In E. coli, CTX-M-28, the most prevalent ESBLs, was identified for the first time in Korea in 44 isolates. In K. pneumoniae, SHV-12 was found in 27 isolates (52.9% of ESBLs), among which 25 isolates also contained SHV-11. Twenty-seven isolates had SHV and CTX-M β-lactamase simultaneously. PABL genes were detected in 39.3% (46/117) of K. pneumoniae and 3.1% (5/159) E. coli. In E. coli, DHA-1(3), CMY-2(1), and CMY-6(1) were detected, whereas in K. pneumoniae, only DHA-1 was detected. Among the PABL-producing organisms, 80.0% (E. coli) and 52.2% (K. pneumoniae) simultaneously produced ESBLs. In conclusion, LTCF residents in Korea have a very high prevalence of E. coli and K. pneumoniae producing ESBLs, PABLs, or both, and the genotypes of ESBL and PABL were identical with those found in general hospitals. [Copyright &y& Elsevier]

Objectives: To examine mutations within the penA, mtrR, porB, ponA and pilQ genes of Neisseria gonorrhoeae to determine their contribution to cephalosporin resistance.Methods: A total of 46 N. gonorrhoeae isolates with reduced susceptibility to cefixime or ceftriaxone (MICs > or = 0.12 mg/L) and two susceptible isolates were selected. The full sequence of penA and partial sequences previously reported as hot mutation sites of the other genes were analysed. Genotyping by N. gonorrhoeae multiantigen sequence typing (NG-MAST) was also performed.Results: A mosaic penicillin-binding protein 2 (PBP 2) was found in a single isolate that exhibited the highest cefixime MIC (0.5 mg/L). The majority of the isolates with reduced susceptibility to cephalosporins contained non-mosaic PBP 2 sequences, of which PBP 2 pattern XIII was most common (28/46). All isolates with reduced susceptibility to cephalosporins also had mtrR and porB mutations. Two susceptible isolates had the PBP 2 pattern XIV and an incomplete MtrR protein, which was a new mutation. Isolates with identical PBP 2 patterns comprised multiple NG-MAST sequence types.Conclusions: Reduced susceptibility of N. gonorrhoeae to ceftriaxone and cefixime was associated with diverse penA mutations, particularly PBP 2 pattern XIII containing an Ala-501-->Val substitution, together with mtrR and porB mutations. The existence of only one strain having the mosaic penA sequence indicated that ceftriaxone and cefixime resistance in Korea is mostly not associated with a mosaic penA sequence. Highly heterogeneous NG-MAST sequence types excluded the clonal expansion of a particular subtype. [ABSTRACT FROM AUTHOR]

Abstract: High-level mupirocin resistance results from the acquisition of a mupirocin resistance (Mupr) plasmid carrying the mupA gene. In this study, we investigated the heterogeneous location of the mupA gene as well as sequence variations in mupA restriction fragment length polymorphism (RFLP) types of high-level mupirocin-resistant (MuH) staphylococci isolated from tertiary hospitals and long-term care facilities in South Korea. RFLP patterns of the mupA gene were investigated in 14 MuH staphylococci isolates, and sequence variations of the cassette-like construction composed of the transfer gene complex (trs), an insertion sequence (IS257-like) and the mupA gene of the Mupr plasmid were also studied. Among the 14 isolates, four different EcoRI/HindIII banding patterns were observed, which were determined to be caused by sequence deletion between the mupA gene and trsLM of the trs gene complex. Four different sequence types were also identified for the trsLM–IS257-like–mupA cassette. The IS257-like sequence of all MuH staphylococci showed two base pair substitutions and one base deletion compared with the sequence of IS257. The heterogeneous location of the mupA gene was caused by sequence deletion adjacent to the IS257-like sequence of the trsLM–IS257-like–mupA cassette construction, and the IS257-like sequence was found in all MuH staphylococci. [Copyright &y& Elsevier]

Abstract: 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). Resistance rates to the major antipseudomonal agents, ceftazidime, imipenem, meropenem, and aztreonam, were 18.8%, 20.5%, 18.7%, and 19.7%, respectively, in 2003. However, they had all decreased to below 10% in 2006. The proportion of multidrug-resistant isolates that were resistant to at least 3 of 5 major antipseudomonal agent decreased from 33.5% in 2003 to 23.1% in 2006 (P < 0.05). In this study, we found a decreasing trend in resistance rates and low resistance rates in P. aeruginosa from non-tertiary care hospitals compared with those from general hospitals, including tertiary care hospitals, in Korea. Our data provide valuable information for the selection of reliable empiric therapies for P. aeruginosa infections in non-tertiary care hospital patients, including outpatients. [Copyright &y& Elsevier]

The article discusses the results of a study that examined the nosocomial transmission of New Delhi metallo-beta-lactamase-1 (NDM-1)-producing Escherichia coli St101 among patients sharing a hospital room in Korea. It noted that the transmission of the NDM-1 was related to poor hygiene standards in the hospital. Stringent infection control procedures including contact barrier precautions and rigorous cleaning resulted to absence of NDM-1-producing Escherichia coli.

Background: Despite the importance of invasive Staphylococcus aureus (ISA) infection, its overall burden in non-selected populations has only been defined in a small number of studies in Europe and North America. To define the characteristics of ISA infections in Korea, we conducted a multi-center cohort study to estimate population-based incidence rates.Methods: We conducted a multicenter prospective cohort study at nine university-affiliated active-surveillance core centers (ASCs) in three regions of Korea. To cover all available clinical microbiologic laboratories, we classified the laboratories in these regions into three groups according to their clinical environment as: 1) Nine ASCs, 2) Five major commercial laboratories and 3) Forty-four acute-care hospital-affiliated microbiology laboratories. We requested all the laboratories to report prospectively their numbers of cases of S. aureus isolated from normally sterile sites. Detailed clinical information was collected about the cases in the nine ASCs.Results: From 1 July 2009 to 30 June 2011, a total of 1,198 cases of ISA infection were identified at the nine ASCs, including 748 (62%) methicillin-resistant S. aureus (MRSA) infections. Most (81%) ISA infections were healthcare-associated (HCA): 653 (55%) hospital-onset and 322 (27%) community-onset. 223 (19%) were community-associated infections. The most common primary diagnosis was catheter-associated infection (225 cases, 19%). Respiratory tract infection (160, 13%), skin & soft tissue (152, 13%) and bone & joint infections (120, 10%) were also common. 30-day and 12-week mortality rates were 25.6% (262/1,024) and 36.5% (314/860), respectively. Complications, including metastatic infection within 12 weeks, occurred in 17.8% of ISA infections. The most common site of metastatic infection was the lung (9.8%, 84/860). Based on the total of 2,806 observed cases of ISA infection, estimated annual rates of ISA and invasive MRSA infections were 43.3 and 27.7 per 100,000 populations, respectively.Conclusions: Our data provide important information about the clinical characteristics of ISA infections. We estimate that over 21,000 ISA infections and 13,000 invasive MRSA infections occurred in Korea in 2010. [ABSTRACT FROM AUTHOR]