Usefulness of electronic stimulation in restless legs syndrome: a pilot study.

PURPOSE: This study aims to investigate the effect of electronic stimulation (ES) as a non-pharmacological treatment in restless legs syndrome (RLS). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Isolation of Coxiella burnetii in patients with nonspecific febrile illness in South Korea.

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.

Impact of Vancomycin MIC on Treatment Outcomes in Invasive Staphylococcus aureus Infections.

There are conflicting data on the association of vancomycin MIC (VAN-MIC) with treatment outcomes in Staphylococcus aureus infections. We investigated the relationship between high VAN-MIC and 30-day mortality and identified the risk factors for mortality in a large cohort of patients with invasive S. aureus (ISA) infections, defined as the isolation of S. aureus from a normally sterile site. Over a 2-year period, 1,027 adult patients with ISA infections were enrolled in 10 hospitals, including 673 (66%) patients with methicillin-resistant S. aureus (MRSA) infections. There were 200 (19.5%) isolates with high VAN-MIC (≥1.5 mg/liter) by Etest and 87 (8.5%) by broth microdilution (BMD). The all-cause 30-day mortality rate was 27.4%. High VAN-MIC by either method was not associated with all-cause 30-day mortality, and this finding was consistent across MIC methodologies and methicillin susceptibilities. We conclude that high VAN-MIC is not associated with increased risk of all-cause 30-day mortality in ISA infections. Our data support the view that VAN-MIC alone is not sufficient evidence to change current clinical practice.

Clinical and Genetic Features of Coxiella burnetii in a Patient with an Acute Febrile Illness in Korea.

Although Q fever is an important zoonotic infection with a worldwide distribution, no human isolates of Coxiella burnetii have been identified in Korea. For the first time, we identified the nucleotide sequence of C. burnetii from a 32-year-old man with an acute febrile illness in Korea. Diagnosis of acute Q fever was confirmed by seroconversion using indirect immunofluorescence antibody assays. Phylogenetic analysis demonstrated high sequence similarity (99.6%-100%) with C. burnetii 16S rRNA sequences identified from the reservoir. These results are the first genetic analysis of C. burnetii in a human case of Q fever in Korea.

The SAV1322 gene from Staphylococcus aureus: genomic and proteomic approaches to identification and characterization of gene function.

BACKGROUND: Bacterial two-component regulatory systems (TCRS) are associated with the expression of virulence factors and antibiotic susceptibility. In Staphylococcus aureus, 16 TCRS types have been identified. The histidine kinase/response regulator SAV1321/SAV1322 in the S. aureus shares considerable homology with the TCRS DesKR in Bacillus subtilis. However, a function for the SAV1322 locus has not yet been assigned. RESULTS: Deletion of the SAV1322 locus in S. aureus results in reduced growth when cultured under low (25 °C) and high (46 °C) temperature conditions. The sav1322 deletion mutant is more tolerant to oxidative stress in vitro and is less pathogenic in a murine infection model when compared with wild-type parent strain Mu50. Furthermore, the sav1322 mutant exhibits lower MICs for gentimicin, tetracyclines and glycopeptides, increased autolysis, and a thinner cell wall when compared with the wild-type strain. Microarray and proteomic analyses show that the expression of cell-wall-associated genes glmS and murZ are lower, and the expression of heat shock and stress-related genes (hrcA, ctsR, dnaK, dnaJ, grpE, clpB, and clpC) are higher in the sav1322 mutant when compared with the wild-type strain. In addition, the sav1322 mutant displays altered expression of proteins involved in carbohydrate/energy metabolism, cell wall metabolism, and stress or heat shock response, as well as other metabolic processes including lipid metabolism, amino acid biosynthesis, purine or pyrimidine metabolism, transcription, and protein biosynthesis. CONCLUSIONS: The S. aureus SAV1322 locus plays a pronounced role in temperature adaptation, antibiotic resistance, and virulence by regulating a wide range of genes and proteins involved in metabolism and stress tolerance.

Characteristics of invasive Staphylococcus aureus infections in three regions of Korea, 2009-2011: a multi-center cohort study.

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.

Molecular characterization of methicillin-resistant Staphylococcus aureus isolates in Korea.

We used several molecular typing methods to analyze 196 methicillin-resistant Staphylococcus aureus (MRSA) and 139 methicillin-susceptible S. aureus (MSSA) isolates collected between 1996 and 2005. The sequence type 72 MRSA has increased in frequency in the community in the Republic of Korea and in hospitals in recent years.

Characterization of two newly identified genes, vgaD and vatH, [corrected] conferring resistance to streptogramin A in Enterococcus faecium.

We characterized two new streptogramin A resistance genes from quinupristin-dalfopristin-resistant Enterococcus faecium JS79, which was selected from 79 E. faecium isolates lacking known genes encoding streptogramin A acetyltransferase. A 5,650-bp fragment of HindIII-digested plasmid DNA from E. faecium JS79 was cloned and sequenced. The fragment contained two open reading frames carrying resistance genes related to streptogramin A, namely, genes for an acetyltransferase and an ATP efflux pump. The first open reading frame comprised 648 bp encoding 216 amino acids with a predicted left-handed parallel ß-helix domain structure; this new gene was designated vatH. [corrected] The second open reading frame consisted of 1,575 bp encoding 525 amino acids with two predicted ATPase binding cassette transporters comprised of Walker A, Walker B, and LSSG motifs; this gene was designated vgaD. vgaD is located 65 bp upstream from vatH, [corrected] was detected together with vatH [corrected] in 12 of 179 quinupristin-dalfopristin-resistant E. faecium isolates, and was located on the same plasmid. Also, the 5.6-kb HindIII-digested fragment which was observed in JS79 was detected in nine vgaD- and vatH-containing [corrected] E. faecium isolates by Southern hybridization. Therefore, it was expected that these two genes were strongly correlated with each other and that they may be composed of a transposon. Importantly, vgaD is the first identified ABC transporter conferring resistance to streptogramin A in E. faecium. Pulsed-field gel electrophoresis patterns and sequence types of vgaD- and vatH-containing [corrected] E. faecium isolates differed for isolates from humans and nonhumans.

Various penA mutations together with mtrR, porB and ponA mutations in Neisseria gonorrhoeae isolates with reduced susceptibility to cefixime or ceftriaxone.

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.

Prevalence of the VNIc genotype of Cryptococcus neoformans in non-HIV-associated cryptococcosis in the Republic of Korea.

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 MATalpha and molecular type VNI. The remaining 4% were C. gattii, serotype B, mating type MATalpha 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.

Bloodstream infections and clinical significance of healthcare-associated bacteremia: a multicenter surveillance study in Korean hospitals.

Recent changes in healthcare systems have changed the epidemiologic paradigms in many infectious fields including bloodstream infection (BSI). We compared clinical characteristics of community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA) BSI. We performed a prospective nationwide multicenter surveillance study from 9 university hospitals in Korea. Total 1,605 blood isolates were collected from 2006 to 2007, and 1,144 isolates were considered true pathogens. HA-BSI accounted for 48.8%, CA-BSI for 33.2%, and HCA-BSI for 18.0%. HA-BSI and HCA-BSI were more likely to have severe comorbidities. Escherichia coli was the most common isolate in CA-BSI (47.1%) and HCA-BSI (27.2%). In contrast, Staphylococcus aureus (15.2%), coagulase-negative Staphylococcus (15.1%) were the common isolates in HA-BSI. The rate of appropriate empiric antimicrobial therapy was the highest in CA-BSI (89.0%) followed by HCA-BSI (76.4%), and HA-BSI (75.0%). The 30-day mortality rate was the highest in HA-BSI (23.0%) followed by HCA-BSI (18.4%), and CA-BSI (10.2%). High Pitt score and inappropriate empirical antibiotic therapy were the independent risk factors for mortality by multivariate analysis. In conclusion, the present data suggest that clinical features, outcome, and microbiologic features of causative pathogens vary by origin of BSI. Especially, HCA-BSI shows unique clinical characteristics, which should be considered a distinct category for more appropriate antibiotic treatment.

Nationwide surveillance study of vancomycin intermediate Staphylococcus aureus strains in Korean hospitals from 2001 to 2006.

We investigated the prevalence and the molecular characteristics of vancomycin-intermediate Staphylococcus aureus (VISA) among methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from clinical samples at tertiary or general hospitals participating in a nationwide surveillance program for VISA and vancomycin-resistant Staphylococcus aureus (VRSA) in Korea during an 8-week period in each year from 2001 to 2006. Of 41,639 MRSAs isolated, 37,856 were screened and 169 grew on brain heart infusion agar supplemented with 4 microg/ml vancomycin. A vancomycin MIC of 4 microg/ml was confirmed for 33 VISA isolates of the 169 isolates. Eighteen of the 33 isolates were classified as hetero-VISA (hVISA) by the population analysis profile (PAP) method. All VISA isolates were susceptible to linezolid, tigecycline, and quinupristin-dalfopristin. Most VISA isolates (MIC 4 microg/ml) showed a PFGE C pattern with sec, seg, and sei enterotoxin genes, including ST5-SCCmec type II, or a PFGE A pattern with sea, including ST239-SCCmec type III.

Alterations in Salience Network Functional Connectivity in Individuals with Restless Legs Syndrome.

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.

Resting-state connectivity and the effects of treatment in restless legs syndrome.

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.

BMD42-2910, a Novel Benzoxazole Derivative, Shows a Potent Anti-prion Activity and Prolongs the Mean Survival in an Animal Model of Prion Disease.

Prion diseases are a group of neurodegenerative and fatal central nervous system disorders. The pathogenic mechanism involves the conversion of cellular prion protein (PrPC) to an altered scrapie isoform (PrPSc), which accumulates in amyloid deposits in the brain. However, no therapeutic drugs have demonstrated efficacy in clinical trials. We previously reported that BMD42-29, a synthetic compound discovered in silico, is a novel anti-prion compound that inhibits the conversion of PrPC to protease K (PK)-resistant PrPSc fragments (PrPres). In the present study, 14 derivatives of BMD42-29 were obtained from BMD42-29 by modifying in the side chain by in silico feedback, with the aim to determine whether they improve anti-prion activity. These derivatives were assessed in a PrPSc-infected cell model and some derivatives were further tested using real timequaking induced conversion (RT-QuIC). Among them, BMD42-2910 showed high anti-prion activity at low concentrations in vitro and also no toxic effects in a mouse model. Interestingly, abundant PrPres was reduced in brains of mice infected with prion strain when treated with BMD42- 2910, and the mice survived longer than control mice and even that treated with BMD42-29. Finally, high binding affinity was predicted in the virtual binding sites (Asn159, Gln 160, Lys194, and Glu196) when PrPC was combined with BMD-42-2910. Our findings showed that BMD42-2910 sufficiently reduces PrPres generation in vitro and in vivo and may be a promising novel anti-prion compound.

National surveillance of antifungal susceptibility of Candida species in South Korean hospitals.

We investigated the species distribution and antifungal susceptibility of Candida isolates from tertiary and non-tertiary hospitals in South Korea from 2002-2004. Of the 612 Candida isolates that were collected, Candida albicans, C. parapsilosis, C. tropicalis, and C. glabrata occurred most frequently, accounting for 97.3% and 96.8% of the isolates in tertiary and non-tertiary hospitals, respectively. C. albicans was the most common isolate, but the incidence of non-C. albicansCandida species was higher than that of C. albicans in tertiary hospitals. The Candida species had much lower MIC(90) to voriconazole (tertiary hospitals: 0.5 microg/ml, non-tertiary hospitals: 0.25 microg/ml) than to fluconazole (tertiary hospitals: 8 microg/ml, non-tertiary hospitals: 4 microg/ml). The MIC(90) of Candida isolates to 5-flucytosine in non-tertiary hospitals was two times higher than that observed in tertiary facilities. The C. glabrata isolates showed a tendency toward strong resistance to fluconazole, but C. parapsilosis isolates were susceptible to all of the evaluated antifungal agents. Voriconazole showed strong in vitro activity against Candida species, especially C. krusei, which is resistant to fluconazole and 5-flucytosine. To our knowledge, this is the first report of Candida antifungal susceptibility that includes non-tertiary hospitals in South Korea.

Investigation of Klebsiella pneumoniae isolates producing SHV-12 and SHV-11 beta-lactamases in Korean hospitals.

Of 143 clinical isolates of Klebsiella pneumoniae collected from Korean non-tertiary hospitals, 24 (16.8%) showed an extended-spectrum beta-lactamase-positive phenotype. PCR and sequence analysis revealed the presence of TEM-116 (n=13), CTX-M-3 (n=5), CTX-M-14 (n=2), CTX-M-15 (n=3), and SHV-12 (n=16). Each of the 24 isolates encoded more than one beta-lactamase, and seven isolates (29%) harbored two different SHV-type beta-lactamase genes (blaSHV-11 and blaSHV-12) bounded by insertion sequence IS26 in a single transferable plasmid.

Case Report: Scrub Typhus and Q Fever Coinfection.

A 56-year-old female goat herder had scrub typhus that persisted after receiving doxycycline for 5 days. Her symptoms continued, prompting us to perform further examinations that revealed coinfection of Q fever and scrub typhus via molecular and serological testing. We also isolated Orientia tsutsugamushi using BALB/c mice and L929 cells.

Sensitivity and specificity evaluation of multiple neurodegenerative proteins for Creutzfeldt-Jakob disease diagnosis using a deep-learning approach.

The diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) can only be confirmed by abnormal protease-resistant prion protein accumulation in post-mortem brain tissue. The relationships between sCJD and cerebrospinal fluid (CSF) proteins such as 14-3-3, tau, and α-synuclein (a-syn) have been investigated for their potential value in pre-mortem diagnosis. Recently, deep-learning (DL) methods have attracted attention in neurodegenerative disease research. We established DL-aided pre-mortem diagnostic methods for CJD using multiple CSF biomarkers to improve their discriminatory sensitivity and specificity. Enzyme-linked immunosorbent assays were performed on phospho-tau (p-tau), total-tau (t-tau), a-syn, and ß-amyloid (1-42), and western blot analysis was performed for 14-3-3 protein from CSF samples of 49 sCJD and 256 non-CJD Korean patients, respectively. The deep neural network structure comprised one input, five hidden, and one output layers, with 20, 40, 30, 20 and 12 hidden unit numbers per hidden layer, respectively. The best performing DL model demonstrated 90.38% accuracy, 83.33% sensitivity, and 92.5% specificity for the three-protein combination of t-tau, p-tau, and a-syn, and all other patients in a separate CSF set (n = 15) with other neuronal diseases were correctly predicted to not have CJD. Thus, DL-aided pre-mortem diagnosis may provide a suitable tool for discriminating CJD patients from non-CJD patients.

Complete genome sequence of Neisseria gonorrhoeae NCCP11945.

Neisseria gonorrhoeae is an obligate human pathogen that is the etiological agent of gonorrhea. We explored variations in the genes of a multidrug-resistant N. gonorrhoeae isolate from a Korean patient in an effort to understand the prevalence, antibiotic resistance, and importance of horizontal gene transfer within this important, naturally competent organism. Here, we report the complete annotated genome sequence of N. gonorrhoeae strain NCCP11945.