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This paper proposes a general stability control method that uses the concept of zero-moment-point (ZMP) and a turning algorithm with a light detection and ranging (LiDAR) sensor for a bipedal alpine skiing robot. There is no elaborate simulator for skiing robots since the snow has complicated characteristics, such as compression and melting. However, real experiments are laborious because of the many varied skiing conditions. The proposed skiing simulator could be used, so that a humanoid robot can track its desired turning radius by modeled forces that are similar to real ones in the snow. Subsequently, the robot will be able to pass through gates with LiDAR sensors. By using ZMP control, the robot can avoid falling down while tracking its desired path. The performance of the proposed stabilization method and autonomous turning algorithm are verified by a dynamics simulation software, Webots, and the simulation results are obtained while using the small humanoid robot platform DARwIn-OP.

Drawing from work adjustment theory and person-environment fit theory, we examine the relationship between job characteristics needs-supplies fit/misfit and affective organizational commitment acro...

Background Scrub typhus, a mite-borne disease caused by bites of Orientia tsutsugamushi-infected chiggers, is endemic in Asia-Pacific countries. In Korea, it is a seasonal disease prevalent in autumn and one of the important causes of acute undifferentiated febrile illness. The purpose of this study was to identify the risk factors for the prediction of the severe clinical course of scrub typhus and to investigate the differences in the clinical and laboratory findings of hospitalized elderly and non-elderly patients with scrub typhus. Materials and methods This study retrospectively reviewed the medical records of patients diagnosed with scrub typhus. Results A total of 710 patients were enrolled and 43.9% of them were elderly patients. The number of patients with complicated scrub typhus was 168 (23.7%) and the most common complication of severe scrub typhus was hepatic dysfunction (10.7%) followed by pneumonia (7.2%), acute kidney injury (4.9%) and shock (2.4%). Blood urea nitrogen ≥20 mg/dL, adenosine deaminase (ADA) ≥100 IU/L, pulmonary edema or pleural effusion, lactate dehydrogenase ≥500 U/L, alkaline phosphatase ≥400 IU/L, ferritin ≥500 ng/mL and absence of skin rash were independently associated with severe scrub typhus. There was no significant difference in the incidence of complicated scrub typhus between elderly and non-elderly patients. Absence of skin rash, pulmonary edema, pleural effusion, serum creatinine ≥1.5 mg/dL, total bilirubin ≥1.5 mg/dL, ADA ≥100 IU/L and ferritin ≥500 ng/mL were significantly associated with a longer hospitalization (≥10 days). Conclusion The several independent predictors of complicated scrub typhus were identified in this study. Absence of skin rash, the increased levels of serum ADA and ferritin were identified as the predictors of complicated scrub typhus, which were also associated with a prolonged hospitalization.

Background Recently, Citrobacter freundii bacteremia outbreak in a neonatal intensive care unit has attracted public attention in Korea. However, Citrobacter bacteremia is uncommon and usually occurs in patients with underlying diseases such as malignancy and hepatobiliary diseases. Increase in resistance and emerging of multidrug resistance among Citrobacter species have gradually been reported. The aim of this study was to investigate the clinical characteristics and outcome of C. freundii and non-freundii bacteremia and antimicrobial susceptibility trends. Materials and methods We reviewed the medical records of patients with Citrobacter bacteremia at St. Mary's Hospital, from 2007 to 2017. Results A total of 43 patients with a median age of 72 (24-93) years was identified and 90.7% of them had comorbidities. Twenty-nine (67.4%) patients had C. freundii bacteremia while 14 had non-freundii bacteremia (six of C. braakii, five of C. koseri, two of C. amalonaticus and one of C. youngae). A total of 26 (51.2%) patients had community-acquired infection and intra-abdominal infection including hepatobiliary tract was the most common portal of entry (24/43, 55.8%). Moreover, hepatobiliary tract was the leading primary site of nosocomial infection (9/17, 52.9%). Polymicrobial bacteremia was observed in 21 (48.8%) patients. The percentages of Citrobacter species susceptible to ampicillin, amikacin, aztreonam, cefazolin, cefoxitin, cefotaxime, cefepime, piperacillin-tazobactam, ciprofloxacin, and imipenem were 9.5%, 97.6%, 73.8%, 9.5%, 14.3%, 71.4%, 92.9%, 83.3%, 83.3% and 100%, respectively. The resistance rate did not increase during the study period. Of 39 patients treated with antibiotics, 36 (92.3%) received appropriate empirical antibiotics. Overall mortality was 18.6%. High Charlson comorbidity index and Pitt bacteremia score were significant risk factors for death in univariate analysis and showed trends in the multivariate analysis. No significant difference in clinical features and antimicrobial susceptibility rate was observed between C. freundii and non-freundii bacteremia. Conclusion Citrobacter bacteremia was predominant in the elderly with comorbidities, while no pediatric case was observed. Hepatobiliary tract is the leading primary focus of bacteremia both in community-acquired and nosocomial infection. The rate of susceptibility to antibiotics has not changed in the last 11 years.

Background: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously.Methods: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem- susceptible clinical strains.Results: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results.Conclusion: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories. (Ann Clin Microbiol 2019;22:9-13)

Background Vertebral osteomyelitis (VO) is a rare but serious condition, and a potentially significant cause of morbidity. Methicillin-susceptible Staphylococcus aureus (MSSA) is the most common microorganism in native VO. Long-term administration of parenteral and oral antibiotics with good bioavailability and bone penetration is required for therapy. Use of oral β-lactams against staphylococcal bone and joint infections in adults is not generally recommended, but some experts recommend oral switching with β-lactams. This study aimed to describe the current status of antibiotic therapy and treatment outcomes of oral switching with β-lactams in patients with MSSA VO, and to assess risk factors for treatment failure. Materials and methods This retrospective study included adult patients with MSSA VO treated at nine university hospitals in Korea between 2005 and 2014. Treatment failure was defined as infection-related death, microbiological relapse, neurologic deficits, or unplanned surgical procedures. Clinical characteristics and antibiotic therapy in the treatment success and treatment failure groups were compared. Risk factors for treatment failure were identified using the Cox proportional hazards model. Results A total of 100 patients with MSSA VO were included. All patients were treated, initially or during antibiotic therapy, with one or more parenteral antibiotics. Sixty-nine patients received one or more oral antibiotics. Antibiotic regimens were diverse and durations of parenteral and oral therapy differed, depending on the patient and the hospital. Forty-two patients were treated with parenteral and/or oral β-lactams for a total duration of more than 2 weeks. Compared with patients receiving parenteral β-lactams only, no significant difference in success rates was observed in patients who received oral β-lactams for a relatively long period. Sixteen patients had treatment failure. Old age (adjusted hazard ratio [HR] 5.600, 95% confidence interval [CI] 1.402 - 22.372, P = 0.015) and failure to improve C-reactive protein levels at follow-up (adjusted HR 3.388, 95% CI 1.168 - 9.829, P = 0.025) were independent risk factors for treatment failure. Conclusion In the study hospitals, diverse combinations of antibiotics and differing durations of parenteral and oral therapy were used. Based on the findings of this study, we think that switching to oral β-lactams may be safe in certain adult patients with MSSA VO. Since limited data are available on the efficacy of oral antibiotics for treatment of staphylococcal VO in adults, further evaluation of the role of oral switch therapy with β-lactams is needed.

Background Genetic polymorphisms of cytochrome P450 enzymes, especially CYP2C19 influence voriconazole pharmacokinetics. However, the impact of CYP2C19 genetic polymorphisms on the therapeutic efficacy and toxicity of voriconazole therapy are not well established. Materials and Methods In this prospective observational study, we analyzed all consecutive adult patients with hematologic diseases who were treated for invasive aspergillosis (IA) with voriconazole between January 2011 and June 2012. CYP2C19 genotype and routine therapeutic drug monitoring of voriconazole were performed. The target range for voriconazole trough levels was 1-5.5 mg/L. Results A total of 104 consecutive patients were enrolled, including 39 homozygous extensive metabolizers (EMs, 38%), 50 heterozygous extensive metabolizers (HEMs, 48%), and 15 poor metabolizers (PMs, 14%). The initial voriconazole trough levels were 1.8, 2.7, and 3.2 mg/L in EMs, HEMs, and PMs, respectively (P = 0.068). Out-of-range initial trough levels were most frequently observed in EMs (46%) followed by HEMs (26%) and PMs (0%) (P = 0.001). The frequency of initial trough levels < 1 mg/L but not > 5.5 mg/L differed significantly among the 3 groups (P = 0.005). However, treatment response, all-cause and IA-attributable mortality, and the occurrence of voriconazole-related adverse events did not differ significantly among the 3 groups (P = 0.399, P = 0.412, P = 0.317, and P = 0.518, respectively). Conclusions While none of the initial voriconazole trough levels in PMs was outside the target range, subtherapeutic initial trough levels were frequent in EMs. Although there was no significant relationship between CYP2C19 genotype and either the clinical outcomes of IA or toxicity of voriconazole, further large-scale multicenter studies using clinical data from homogeneous populations are required.

[Purpose] The purpose of this study was to determine the effects of a 4-week program of active condylar rotation exercise on the extent of the lateral mandibular shift during mouth opening in patients with temporomandibular disorder. [Subjects and Methods] Patients with temporomandibular disorder (n = 12; 7 men and 5 women) were recruited. The active range of temporomandibular motion was recorded using 3-dimensional ultrasound-based motion analysis. The paired t-test was used to assess changes in lateral mandibular shift before and after active condylar rotation exercise. [Results] The degree of the lateral mandibular shift during mouth opening and the mouth opening-lateral mandibular shift ratio were significantly lower after active condylar rotation exercise than before the exercise. [Conclusion] Active condylar rotation exercise may effectively reduce the degree of the lateral mandibular shift during mouth opening to produce symmetrical mouth opening in patients with mild temporomandibular disorder.

Limited hip flexion may lead to a poor lumbopelvic motion during seated active hip flexion in people with low-back pain (LBP). The purpose of this study was to compare lumbopelvic motion during seated hip flexion between subjects with and without LBP accompanying limited hip flexion.Fifteen patients with LBP accompanying limited hip flexion and 16 healthy subjects were recruited. The subjects performed seated hip flexion with the dominant leg three times. A three-dimensional motion-analysis system was used to measure lumbopelvic motion during seated hip flexion.During seated active hip flexion, the angle of hip flexion was significantly lower in patients with LBP accompanying limited hip flexion (17.4 ± 4.4 in the LBP group, 20.8 ± 2.6 in the healthy group; t = 2.63, p = 0.014). The angle of the lumbar flexion (4.8 ± 2.2 in the LBP group, 2.6 ± 2.0 in the healthy group; t = -2.96, p = 0.006) and posterior pelvic tilting (5.0 ± 2.6 in the LBP group, 2.9 ± 2.0 in the healthy group; t = 2.48 p = 0.019), however, were significantly greater in patients with this condition.The results of this study suggest that limited hip flexion in LBP can contribute to excessive lumbar flexion and posterior pelvic tilting during hip flexion in the sitting position. Further studies are required to confirm whether improving the hip flexion range of motion can reduce excessive lumbar flexion in patients with LBP accompanying limited hip flexion.

The time to positivity (TTP) of blood cultures is associated with the microbial load in the blood and prognosis in patients with bloodstream infections caused by various bacterial species. However, relevant information about the TTP for Candida species in candidaemia is limited. We investigated the clinical impact of the TTP on mortality in patients with candidaemia.All consecutive patients ≥ 18 years of age with candidaemia between January 2006 and July 2012 were included. The demographics, clinical and microbiological characteristics, antifungal treatment and outcomes of the patients were collected retrospectively.A total of 152 patients were identified. The overall mortality rate at 6 weeks was 53%. The median TTP for Candida isolates was 27 h (IQR 19-37 h). A TTP of ≤ 24 h was significantly related to a higher mortality rate (P = 0.021). In a multivariate Cox regression analysis, the Charlson comorbidity index value [adjusted hazard ratio (HR) 1.15, 95% CI 1.02-1.29, P = 0.018], sequential organ failure assessment score (adjusted HR 1.23, 95% CI 1.13-1.34, P0.001), TTP ≤ 24 h (adjusted HR 2.74, 95% CI 1.51-4.97, P = 0.001), timing of appropriate antifungal therapy72 h (adjusted HR 2.38, 95% CI 1.26-4.51, P = 0.008) and persistent candidaemia (adjusted HR 2.50, 95% CI 1.33-4.72, P = 0.005) were independently associated with the 6 week mortality rate.A short TTP (≤ 24 h) for Candida species was independently associated with increased mortality in patients with candidaemia. Additional studies on the relevance of the TTP to clinical outcome in patients with candidaemia are needed.

The purpose of this study was to assess the intra-rater test-retest reliability of tibial external rotation angle measurement using a smartphone-based photographic goniometer, DrGoniometer (DrG) compared to a three-dimensional motion analysis system (Vicon). The current study showed an interchangeable method using DrG to measure the tibial external rotation angle in standing knee flexion at 90˚. Twelve healthy subjects participated in this study. A rest session was conducted 30 minutes later for within-day reliability and five days later for between-day intra-rater test-retest reliability. To assess the validity of the measurement using DrG, we used a three dimensional motion analysis system as a gold standard to measure the angle of tibial external rotation. Intra-class correlation coefficient (ICC) and the standard error of measurement (SEM) values were used to determine the within-and between-day intra-rater test-retest reliability of using DrG and a three dimensional motion analysis system. To assess validity, Pearson correlation coefficients were used for two measurement techniques. The measurement for tibial external rotation had high intra-rater test-retest reliability of within-day (ICC=.88) and between-day (ICC=.83) reliability using DrG and of within-day (ICC=.93) and between-day (ICC=.77) reliability using a three-dimentional motion analysis system. Tibial external rotation angle measurement using DrG was highly correlated with those of the three-dimensional motion analysis system (r=.86). These results represented that the tibial external rotation angle measurement using DrG showed acceptable reliability and validity compared with the use of three-dimensional motion analysis system.

The purpose of this study was to compare the immediate effects of upper trapezius muscle stretching in more tensed position (MTP) and less tensed position (LTP) on the change of range of motion (ROM) for neck rotation, and the ROM for conjunct neck motions at end-range of neck rotation toward the painful side in patients with unilateral neck pain. Eighteen patients with unilateral neck pain were recruited for the study`s MTP group, and 18 age-, weight- and gender-matched patients with unilateral neck pain were recruited for LTP group. The ROM changes in active neck primary and conjunct motions were measured using a cervical ROM inclinometer in the sitting position. Our results showed that both upper trapezius stretching method in MTP and LTP were significantly effective in increasing the ROM of neck rotation toward painful side in patients with unilateral neck pain. However, a significantly greater increase in the ROM for neck rotation and a further decrease in conjunct neck extension during neck rotation toward the painful side were shown in MTP group, compared to LTP group. The upper trapezius stretching in MTP is useful in increasing the ROM of neck rotation and decreasing the range of conjunct neck extension during neck rotation toward the painful side in patients with unilateral neck pain.

BACKGROUND: Overuse of the extensor carpi radialis (ECR) may play a role in the development of lateral epicondylitis (LE). However, no studies have investigated the muscle activity ratio between the ECR and extensor carpi ulnaris (ECU) associated with the kinematics during wrist extension in workers with LE. OBJECTIVE: We compared the ratio (ECR/ECU) of muscle activity between the ECR and ECU and the kinematics of the wrist during wrist extension between workers with and without LE. METHODS: Fifteen automobile assembly line workers with LE and 15 workers without LE participated in this study. The ratio of muscle activity was measured using surface electromyography, and wrist kinematics were measured by a threedimensional motion analysis system while the workers extended their wrists actively to the maximum range to which they did not feel uncomfortable. RESULTS: Significantly greater ratios of muscle activity, ranges of radial deviation, and combined motion of radial deviation and extension (CMDE) were shown in workers with LE compared to those without LE. Also, the range of wrist extension was significantly lower in workers with LE than in those without LE. CONCLUSIONS: Quantifying the ratio of muscle activity with altered kinematics of wrist extension may help researchers to understand why overuse of ECR is occurring and explain LE development in automobile assembly line workers.

We report the development of a colorimetric sensor that allows for the quantitative measurement of the acid content via acid-base titration in a single-step. In order to create the sensor, we used a cobalt coordination system (Co-complex sensor) that changes from greenish blue colored Co(H2O)4(OH)2 to pink colored Co(H2O)6(2+) after neutralization. Greenish blue and pink are two complementary colors with a strong contrast. As a certain amount of acid is introduced to the Co-complex sensor, a portion of greenish blue colored Co(H2O)4(OH)2 changes to pink colored Co(H2O)6(2+), producing a different color. As the ratio of greenish blue and pink in the Co-complex sensor is determined by the amount of neutralization reaction occurring between Co(H2O)4(OH)2 and an acid, the sensor produced a spectrum of green, yellow green, brown, orange, and pink colors depending on the acid content. In contrast, the color change appeared only beyond the end point for normal acid-base titration. When we mixed this Co-complex sensor with different concentrations of citric acid, tartaric acid, and malic acid, three representative organic acids in fruits, we observed distinct color changes for each sample. This color change could also be observed in real fruit juice. When we treated the Co-complex sensor with real tangerine juice, it generated diverse colors depending on the concentration of citric acid in each sample. These results provide a new angle on simple but quantitative measurements of analytes for on-site usage in various applications, such as in food, farms, and the drug industry.

Introduction.Streptococcus pneumoniaeis an important pathogen with high morbidity and mortality rates. The aim of this study was to evaluate the distribution of common serotypes and antimicrobial susceptibility ofS. pneumoniaein Korea.Methods. A total of 378 pneumococcal isolates were collected from 2008 through 2014. We analyzed the serotype and antimicrobial susceptibility for both invasive and noninvasive isolates.Results. Over the 7 years, 3 (13.5%), 35 (10.8%), 19A (9.0%), 19F (6.6%), 6A (6.1%), and 34 (5.6%) were common serotypes/serogroups. The vaccine coverage rates of PCV7, PCV10, PCV13, and PPSV23 were 21.4%, 23.3%, 51.9%, and 62.4% in all periods. The proportions of serotypes 19A and 19F decreased and nonvaccine serotypes increased between 2008 and 2010 and 2011 and 2014. Of 378S. pneumoniaeisolates, 131 (34.7%) were multidrug resistant (MDR) and serotypes 19A and 19F were predominant. The resistance rate to levofloxacin was significantly increased (7.2%).Conclusion. We found changes of pneumococcal serotype and antimicrobial susceptibility during the 7 years after introduction of the first pneumococcal vaccine. It is important to continuously monitor pneumococcal serotypes and their susceptibilities.

Ely's test is commonly used to assess rectus femoris muscle flexibility. however, a reliability limit of this test was demonstrated by a previous study. In this study, we present an alternative method using an application for a digital horizontal level in a smartphone (DHLS) to complement the reliability limit of Ely's test. The aim of this study was to examine the reliability of Ely's test using DHLS on the pelvis, compared to using visual observation (VO) of pelvic and hip motions. Nineteen patients with lumbar extension-rotation syndrome were recruited for this study. An examiner examined the rectus femoris flexibility (both pass/fail and goniometer scoring) through Ely's test using both DHLS and VO. A retest session was completed two hours later for within-day reliability and seven days later for between-day intra-rater test-retest reliability. Results showed higher Kappa values for pass/fail scoring and higher intraclass correlation coefficient values for goniometer scoring in Ely's test using DHLS, compared to using VO. Measurement error and Bland and Altman plots further demonstrated the degree of intra-rater variance during Ely's test using DHLS in a clinical setting, compared to using VO. These results demonstrated that Ely's test using DHLS showed acceptable reliability compared to using VO. Ely's test using DHLS could be widely used for measuring the rectus femoris muscle flexibility in patients with lumbar extension-rotation syndrome, although the inter-rater reliability needs to be established first.

Escherichia coli and Klebsiella pneumoniae are main pathogens in neutropenic fever even if the proportion of Gram-positive cocci is increasing. Extended-spectrum β-lactamases (ESBL)-producing organisms are an emerging problem in nosocomial infection. Nevertheless, until now, information about risk factors for the acquisition and clinical outcomes of bacteremia due to ESBL-producing organisms is limited in neutropenic patients. From medical records collected between January 2007 and December 2008, we identified a total of 101 consecutive patients who developed bacteremia due to E. coli (n = 87) or K. pneumoniae (n = 14). Twenty-six (26 %) cases of bacteremia were caused by ESBL-producing organisms. A hospital stay of >2 weeks during the 3 months preceding bacteremia [adjusted odds ratio (OR), 5.887; 95 % confidence interval (CI), 1.572–22.041] and the use of broad-spectrum cephalosporins in the 4 weeks prior to bacteremia (adjusted OR, 6.186; 95 % CI, 1.616–23.683) were significantly related to the acquisition of ESBL. Twenty-four (92 %) of the ESBL-producing organisms were susceptible to either piperacillin–tazobactam or amikacin. Aminoglycosides (amikacin or isepamicin) were the main appropriate antimicrobial agents used against the ESBL-producing isolates during the initial empirical treatment (16/22, 73 %). However, the 30-day mortality rates for ESBL bacteremia and non-ESBL bacteremia were not significantly different (15 vs 5 %; p = 0.199). As alternatives to carbapenem, piperacillin–tazobactam plus amikacin or isepamicin combinations may be effective empirical therapeutic options for patients with neutropenic fever who are at high risk of developing bacteremia with ESBL-producing pathogens.

To determine the most effective exercise to specifically activate the scapular posterior tilting muscles by comparing muscle activity generated by different exercises (wall facing arm lift, prone arm lift, backward rocking arm lift, backward rocking diagonal arm lift).Repeated-measure within-subject intervention.The subjects were 20 healthy young men and women.Lower trapezius (LT) and serratus anterior (SA) muscle activity was measured when subjects performed the four exercises.Muscle activity was significantly different among the four exercise positions (p0.05). The backward rocking diagonal arm lift elicited significantly greater activity in the LT muscle than did the other exercises (p0.05). The backward rocking arm lift showed significantly more activity in the SA muscle than did the other exercises (p0.05).Clinicians can use these results to develop scapular posterior tilting exercises that specifically activate the target muscle.

Reduced vancomycin susceptibility in Staphylococcus aureus can cause serious problems relating to treatment failure and persistent infection. We investigated vancomycin susceptibility, genetic relationships and transcriptional changes of the accessory gene regulator (agr) in vancomycin-intermediate S. aureus (VISA) strains isolated from South Korea compared with vancomycin-susceptible S. aureus (VSSA) strains. Molecular characterization, population analysis profiling, agr sequencing and transcriptional profiling of RNAIII by real-time RT-PCR were performed. Of 16 VISA strains tested, eight exhibited ST5, agr II and type II SCCmec. The others exhibited ST239, agr I and type III SCCmec. A point mutation in AgrA (Asp8Gly or Ile238Lys) was found in only five VISA strains; no mutations were detected in the other strains. However, RNAIII levels markedly decreased in all VISA strains (mean of 1.39-fold change) compared with the VSSA strains (31.51-fold change) in late-exponential phases (P

To define the risk factors and clinical outcomes of community-onset bacteremia caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBLEC), we analyzed 50 consecutive cases of community-onset bacteremia caused by ESBLEC at a secondary hospital in South Korea from 2005 to 2010. Risk factors were assessed by conducting a case-double control study in which cases were compared with (1) control patients with community-onset bacteremia due to non-ESBLEC, and (2) those with community-onset bacteremia not caused by E. coli. Clinical outcome was assessed among patients with community-onset E. coli bacteremia. Community-onset bacteremia due to ESBLEC accounted for 6.7% of all community-onset E. coli bacteremia. In addition, an increasing proportion of ESBLEC among patients without any healthcare risk factors was observed. Comparison with both control groups revealed that the recent use of antibiotics (odds ratio [OR], 4.3; 95% confidence interval [CI], 1.5-12.3) was an independent risk factor for ESBL acquisition. Factors influencing the 30-day mortality were a high Acute Physiology and Chronic Health Evaluation (APACHE) II score (OR, 1.5; 95% CI, 1.1-2.0) and severe sepsis or septic shock (OR, 26.6; 95% CI, 1.5-470.7) and malignancy (OR, 11.9; 95% CI, 1.1-134.8). Increased mortality was not statistically associated either with ESBL production or with inappropriate empirical therapy. ESBLEC has emerged as a significant cause of community-onset bacteremia in this hospital, suggesting that ESBLEC are widely disseminated in the South Korean community.

Background We investigated the prevalence of plasmid-mediated quinolone resistance and its association with extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase in Enterobacteriaceae. Methods A total of 347 non-duplicated isolates of Enterobacteriaceae were collected between August and October 2006 from 2 hospitals. Qnr determinant screening was conducted using PCR amplification, and all positive results were confirmed by direct sequencing. Qnr-positive strains were determined on the basis of the presence of ESBL and AmpC beta-lactamase genes. Results The qnr gene was detected in 47 of 347 clinical Enterobacteriaceae isolates. Among the 47 qnr-positive strains, Klebsiella pneumoniae (N=29) was the most common, followed by Escherichia coli (N=6), Enterobacter cloacae (N=6), Citrobacter freundii (N=5), and Enterobacter aerogenes (N=1). These isolates were identified as qnrA1 (N=6), 8 qnrB subtypes (N=40), and qnrS1 (N=1). At least 1 ESBL was detected in 38 of the 47 qnr-positive strains. Qnr-positive strains also showed high positive rates of ESBL or AmpC beta-lactamase, such as TEM, SHV, CTX-M, and DHA. DHA-1 was detected in 23 of 47 qnr-positive strains, and this was co-produced with 1 qnrA1 and 22 qnrB4. Strains harboring MIR-1T and CMY were also detected among the qnr-positive strains. Antimicrobial-resistance rates of qnr-positive strains to ciprofloxacin, levofloxacin, norfloxacin, nalidixic acid, and moxifloxacin were 51.1%, 46.8%, 46.8%, 74.5%, and 53.2%, respectively. Conclusions The qnr genes were highly prevalent in Enterobacteriaceae, primarily the qnrB subtypes. They were closely associated with EBSL and AmpC beta-lactamase.

Summary Invasive aspergillosis (IA) remains an important cause of mortality in acute leukaemia patients. Previous studies reported that serum galactomannan (GM) levels correlate strongly with IA outcomes in patients with haematological cancers. This study aimed to clarify the usefulness of serial GM testing for outcome evaluation of IA in acute leukaemia patients. We retrospectively analysed 58 acute leukaemia patients who had IA during neutropenic period after chemotherapy and whose serum GM was serially monitored until discharge or death. The kappa correlation coefficient was used to determine the strength of correlation between GM and clinical outcome (survival or death) of IA. The correlation between clinical outcome and GM kinetics was good at week 6 [κ = 0.663, 95% confidence interval (CI): 0.465–0.861] and excellent at week 12 (κ = 0.819, 95% CI: 0.667–0.91). Survival was significantly better in patients whose GM values normalised than in patients with persistently positive GM (P

Introduction Coagulase-negative staphylococcus (CoNS) is the most common pathogen in continuous ambulatory peritoneal dialysis (CAPD)–associated peritonitis. There is no well-organized, standardized database for CoNS, and few studies have used gene sequencing in reporting species distribution in CAPD peritonitis. In the present study, we used 3 housekeeping genes to evaluate the prevalence of CoNS isolated from CAPD peritonitis episodes and to estimate the accuracy of, and the characteristic differences between, these genes for species identification. Methods All 51 non-duplicated CoNS isolates obtained from CAPD peritonitis between April 2006 and May 2008 were used. The strains were identified by polymerase chain reaction and by direct sequencing using the 16S ribosomal RNA (rRNA), tuf, and sodA genes. We determined species distribution, and using selected databases, we analyzed the characteristics and diagnostic utility of the individual genes for species identification. Results In GenBank (National Institutes of Health, Bethesda, MD, USA), we found 49 type or reference strains for CoNS 16S rRNA, 17 for tuf, and 46 for sodA, and we used those data for sequence-similarity comparisons with CAPD isolates. Among our 51 strains, S. epidermidis (66.7%) was the most common, followed by S. haemolyticus (11.8%), S. warneri (7.8%), S. caprae (5.9%), S. capitis (3.9%), and S. pasteuri (2.0%). For 1 strain, different species results were obtained with each gene. The identification rates with 16S rRNA, sodA, and tuf gene sequencing were 84.0%, 96.0%, and 92.2% respectively. The discrimination capability of 16S rRNA gene was lower in a few individual species, and for the sodA gene, the percentage similarity to sequences from reference strains was also lower. The tuf gene had excellent identification capacity, but relatively few type strains are available in public databases. The 16S rRNA gene did not discriminate between S. caprae and S. capitis. The sodA gene showed a similarity rate that was lower than that for sequences of the 16S rRNA gene. The tuf type strain sequences for S. caprae and S. pasteuri are not available in public databases. Conclusions The sodA, tuf, and 16S rRNA genes were very useful for CoNS identification. Each has its own characteristics of similarity, discriminative power, and inclusion in databases.

While the epidemiology and clinical differences of various Candida spp. has been relatively well-identified, data regarding invasive aspergillosis (IA) caused by different Aspergillus spp. are insufficient. We aimed to determine the epidemiology of culture-positive invasive pulmonary aspergillosis (IPA) and to compare the characteristics and outcomes of Aspergillus fumigatus IPA with those of non-fumigatus IPA in patients with hematologic diseases. All consecutive cases of IPA from 2011 to 2015 were reviewed retrospectively. There were 430 proven/probable IPA and 76 culture-positive proven/probable IPA. Excluding cases of multiple species of fungi or cases having difficulties in species-level identification, 41 A fumigatus and 22 non-fumigatus IPA (Aspergillus flavus [n = 11], Aspergillus niger [n = 6], and Aspergillus terreus [n = 5]) were compared. There were no significant differences in baseline characteristics between the 2 groups. However, disseminated IA was more common in non-fumigatus IPA (2.4% vs 18.2%; P = .046). Paranasal sinus (PNS) involvement was more common in non-fumigatus IPA. There was a trend towards higher peak serum galactomannan values in non-fumigatus IPA than in A fumigatus IPA group (median 1.33 [interquartile 0.98–3.29] vs 0.97 [0.66–1.97]; P = .084). Clinical response and mortality did not differ between groups. The culture-positive rate of proven/probable IPA was 17.7%, of which non-fumigatus Aspergillus accounted for about one-third. Disseminated IA, especially involving the PNS, was more frequent in non-fumigatus IPA than in A fumigatus IPA.

Objectives. To evaluate the incidence of infectious complications after receiving alemtuzumab as part of a conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in Korean patients. Methods. From November 2004 to January 2006, 12 patients who received alemtuzumab-based conditioning regimens for allogeneic HSCT were evaluated retrospectively until death or until the end of the follow-up in July 2007; they were compared with 18 patients who received rabbit anti-thymocyte globulin (ATG)-containing conditioning regimens from January 2002 to January 2006. Results. Post-engraftment infections occurred more frequently in the alemtuzumab recipients than in the ATG recipients; the mean number of infections, excluding cytomegalovirus (CMV) infections, per patient during the follow-up period was 2.6±1.4 vs. 1.0±0.8 (P=0.003), respectively. Although there was no statistical difference in the cumulative incidence of CMV infection between the 2 groups (91.7% vs. 55.6%, P=0.381), the alemtuzumab recipients had a higher incidence of CMV diseases (41.6% vs. 0%, P=0.0006) and a higher recurrence rate of CMV infection (90.0% vs. 27.3%, P=0.008) than did the ATG recipients, irrespective of the dose of alemtuzumab. Hemorrhagic cystitis (HC) (66.7% vs. 16.7%, P=0.009) and BK virus-associated HC (41.7% vs. 5.6%, P=0.026) developed more frequently in the alemtuzumab recipients. The all-cause mortality rate was not significantly different between the alemtuzumab and the ATG recipients (75% vs. 55.6%, P=0.28). Conclusion. Alemtuzumab recipients had a high incidence of CMV disease as well as BK virus-associated HC compared with the ATG recipients. The dose of alemtuzumab should be tailored to patients' risk; in addition, the implementation of the appropriate prophylaxis for CMV and early detection strategies for BK virus are recommended.

Meticillin-resistant Staphylococcus aureus (MRSA) strains harbouring staphylococcal cassette chromosome mec (SCCmec) type IVA are known to be more prevalent in South Korea than in other countries. Variations in the SCCmec IVA structure have been identified, including in sequence type (ST) 1 and ST72 strains. This study compared and investigated the genetic characteristics of two subtypes common in South Korea. Type IVA SCCmec of ST1 strains was characterized by type IV features with the linearized pUB110 at the junkyard (J) 3 region. However, that of ST72 strains carried a variant class B mec complex, ccrA2, with an identity of ∼96 % and the linearized pUB110 at the J3 region. In SCCmec of ST72 strains, the organization of the class B variant and the J3 region may be more similar to that of type IA than to other types, but the ccr type and other J regions seemed to be derived from type IV. These genetic characteristics showed that type IVA appears to result from the dynamic genetic exchange and recombination of SCC DNA.

Summary Posaconazole was introduced as the primary antifungal prophylaxis (PAP) in acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS) patients during remission induction chemotherapy. Data on breakthrough invasive fungal infections (IFIs) from various centres are essential, as there are several considerations in treating IFIs in the posaconazole era. The aim of this study was to evaluate the effectiveness of posaconazole PAP and identify characteristics of IFIs at a single centre in Korea. We retrospectively reviewed consecutive patients with AML/MDS undergoing remission induction chemotherapy between December 2010 and November 2013. Of the 424 patients, 140 received posaconazole and 284 received fluconazole prophylaxis. The incidence of breakthrough proven/probable IFIs (15.5% vs. 2.9%, P

Purpose Posaconazole is effective for the prophylaxis of invasive fungal infections (IFIs) in patients with acute myeloid leukemia or myelodysplastic syndrome during remission induction chemotherapy. However, a cost–benefit analysis of posaconazole versus fluconazole or itraconazole has not been conducted in Korea. Methods We retrospectively reviewed data for all consecutive patients who received primary antifungal prophylaxis during remission induction chemotherapy in our acute myeloid leukemia/myelodysplastic syndrome cohort from December 2010 to November 2013. Patient characteristics and factors known as a risk of IFI were matched with propensity score analysis. We evaluated the medical cost according to the prophylactic antifungal agents (posaconazole vs fluconazole/itraconazole), the development of breakthrough IFIs, and survival status after propensity score matching in a 1:1 ratio. Findings Of the 419 baseline patients, 100 patients in each group were analyzed after matching. A significant decrease was found in the development of breakthrough proven or probable IFIs (3.0% vs 14.0%; P = 0.009) and the rate of empirical antifungal therapy (EAFT) (12.0% vs 46.0%; P 0.001) in the posaconazole group. Total in-hospital medical costs per patient were not statistically different between posaconazole and fluconazole/itraconazole prophylaxis. However, the daily medical cost was lower for posaconazole prophylaxis, resulting in a total daily cost savings of $72 (₩79,458) per patient ( P = 0.002). In the cases of breakthrough proven/probable IFIs, EAFT, and in-hospital deaths, the total medical costs per patient were significantly higher than in nonproven/probable IFIs, non-EAFT, and in-hospital survivors, as much as $7,916 (₩8,700,758), $4605 (₩5,062,529), and $11,134 (₩12,238,422), respectively. Costs for the antifungal agent used in targeted or empirical therapy were lower in the posaconazole group, resulting in a savings of $697 (₩766,347) per patient ( P 0.001). Implications Posaconazole appears to be cost beneficial for primary antifungal prophylaxis in high-risk patients with hematologic malignancy, at a single center, in Korea. Cost–benefit is closely related with clinical outcomes, including breakthrough IFI development, EAFT, and survival status.

Nonspecific low back pain (LBP) is a common musculoskeletal problem that is intensified during physical activity. Patients with LBP have been reported to change their abdominal muscle activity during walking; however, the effects of pain intensity, disability level, and fear-avoidance belief on this relationship have not been evaluated. Thus, we compared abdominal muscle activity in patients with LBP and asymptomatic controls, and assessed the impact of pain intensity, disability level, and fear-avoidance belief. Thirty patients with LBP divided into groups reporting low (LLBP) and high-pain intensity low back pain (HLBP), and 15 participants without LBP were recruited. LBP patients’ self-reported pain intensity, disability, and fear-avoidance belief were recorded. To examine abdominal muscle activity (rectus abdominis [RA], internal [IO], and external oblique [EO] muscles) during walking, all subjects walked at a self-selected speed. Abdominal muscle activity (RA, IO, and EO) was compared among groups (LLBP, HLBP, and controls) in different phases of walking (double support vs swing). Relationships between abdominal muscle activity and clinical measures (pain intensity, disability, fear-avoidance belief) were analyzed using partial correlation analysis. Right IO muscle activity during walking was significantly decreased in LLBP and HLBP compared with controls in certain walking phase. Partial correlation coefficients showed significant correlations between fear-avoidance belief and right EO activity (r = .377, P .05). This study demonstrated decreased IO muscle activity during certain walking phases in LLBP and HLBP compared with asymptomatic participants. Although altered IO muscle activity during walking was observed in patients with LBP, no changes were found with other abdominal muscles (EO, RA). Thus, these results provide useful information about abdominal muscle activity during walking in patients with LBP.

Purpose To describe the incidence, clinical courses, and risk factors for mortality of lower respiratory tract diseases (LRDs) caused by common respiratory viruses (CRVs) in stem cell transplantation (SCT) recipients. Materials and methods We retrospectively reviewed the medical records of 1038 patients who received SCT between January 2007 and August 2011 at a single center in Korea. Results Seventy-one CRV-LRDs were identified in 67 (6.5%) patients. The human parainfluenza virus (HPIV) was the most common causative pathogen of CRV-LRDs at 100 days [cumulative incidence estimate, 23.5%; 95% confidence interval (CI), 3.3-43.7] and 1 year (cumulative incidence estimate, 69.2%; 95% CI, 45.9-92.5) following SCT. The 30-day overall mortality rates due to influenza-LRDs, respiratory syncytial virus-LRDs, HPIV-LRDs, and human rhinovirus-LRDs were 35.7, 25.8, 31.6, and 42.8%, respectively. Co-pathogens in respiratory specimens were detected in 23 (33.8%) patients. The overall mortality at day 30 after CRV-LRD diagnosis was 32.8% (22/67). High-dose steroid usage (p=0.025), a severe state of immunodeficiency (p=0.033), and lymphopenia (p=0.006) were significantly associated with death within 30 days following CRV-LRD diagnosis in a univariate analysis. Multivariate logistic regression analysis revealed that high-dose steroid usage [odds ratio (OR), 4.05; 95% CI, 1.12-14.61; p=0.033] and lymphopenia (OR, 6.57; 95% CI, 1.80-24.03; p=0.004) were independent risk factors for mortality within 30 days of CRV-LRDs. Conclusion CRV-LRDs among SCT recipients showed substantially high morbidity and mortality rates. Therefore, the implement of an active diagnostic approaches for CRV infections is required for SCT recipients with respiratory symptoms, especially those receiving high-dose steroids or with lymphopenia.

Purpose Posaconazole is a second-generation triazole with a broad spectrum. However, there is a lack of data to support a significant role for posaconazole in the treatment of invasive fungal infection (IFI), especially in Korea. Until recently, posaconazole was available only through the Korean Orphan Drug Center. This study was designed to review the use of posaconazole at a single-center in Korea. Materials and methods Data from patients who received posaconazole treatment at Catholic Blood and Marrow Transplantation Center were retrospectively reviewed between January 2007 and September 2012. Results A total of 11 cases (3 males and 8 females, median age 52 years) received posaconazole. Five patients were given the drug for mucormycosis, two for invasive aspergillosis, and four for unspecified IFI for which galactomannan (GM) assays were negative. The treatment duration ranged from 4-250 days. Three patients received posaconazole for management refractory IFI, two for intolerance of previous antifungal therapy, and six for long-term maintenance treatment. The overall successful response rate to posaconazole was 55% (six of eleven patients). Five of eleven patients died during the study period. However, only one death was attributed to the progression of IFI. None of the patients discontinued posaconazole therapy due to adverse events. Conclusion Posaconazole is an attractive oral antifungal agent for salvage treatment of IFI, particularly upon diagnosis of mucormycosis or in cases in which mucormycosis cannot be ruled out due to a negative GM.

Summary Accumulation of eight key mutations located in the X/preC regions of the hepatitis B virus (HBV) genome (G1613A, C1653T, T1753V, A1762T, G1764A, A1846T, G1896A and G1899A) is a risk marker for the development of hepatocellular carcinoma (HCC). In this study, we analysed the 8 key mutations in 442 serum samples collected from 310 non-HCC and 132 HCC patients to identify the combinations linked to HCC. After the patients were stratified according to the age groups and mutation combinations, clinical parameters were compared between the HCC and the non-HCC groups. Analyses were focused on patient ≥40 years of age infected by HBV genotype C with A1762T and G1764A mutations in the basal core promoter region (BCP double mutation). In patients with ≥6 mutations, the combination of [G1613A + C1653T + A1846T + G1896A] mutations was closely linked to HCC, whereas no specific single or double mutation combination was associated with HCC. In patients with ≤5 mutations, HBeAg and HBV DNA serum titres were lower in the HCC group than those in the non-HCC group. Unlike the number of mutations, no specific combination correlated with advanced clinical stage in HCC. Of the BCP double mutation–based HBV mutant types, combinations of ≥6 mutations that include G1613A + C1653T + A1846T + G1896A, and combinations of ≤5 mutations with reduced HBeAg production, may be more specific indicators of HCC risk than only the number of mutations or any specific combination(s).

Background Vancomycin-resistant Enterococcus (VRE) bloodstream infection (BSI) is generally associated with the delayed administration of adequate antibiotics. The identification of risk factors and outcomes of VRE BSI is necessary for establishing strategies for managing neutropenic fever in patients with hematological malignancies. Methods We retrospectively analysed consecutive cases of enterococcal BSI in patients with neutropenia after chemotherapy or stem cell transplantation between July 2009 and December 2011 at a single center. Results During the 30-month period, among 1,587 neutropenic patients, the incidence rate of enterococcal BSI was 1.76 cases per 1,000 person-days. Of the 91 enterococcal BSIs, there were 24 cases of VRE. VRE BSI was associated with E. faecium infection (P < .001), prolonged hospitalization (P = .025) and delayed administration (≥48 hours after the febrile episode) of adequate antibiotics (P = .002). The attributable mortality was 17% and 9% for VRE and vancomycin-susceptible Enterococcus (VSE), respectively (P = .447). The 30-day crude mortality was 27% and 23% for VRE and VSE, respectively (OR 1.38, 95% CI 0.53–3.59; P = .059). Only SAPS-II was an independent predictive factor for death (adjusted OR 1.12, 95% CI 1.08–1.17; P < .001). Conclusions In conclusion, vancomycin resistance showed some trend towards increasing 30-day mortality, but is not statistically significant despite the delayed use of adequate antibiotics (≥48 hours). Only underlying severity of medical condition predicts poor outcome in a relatively homogeneous group of neutropenic patients.

Gram-positive bacteria naturally produce extracellular vesicles. However, little is known regarding the functions of Gram-positive bacterial extracellular vesicles, especially in the bacterial community. Here, we investigated the role of Staphylococcus aureus extracellular vesicles in interbacterial communication to cope with antibiotic stress. We found that S. aureus liberated BlaZ, a β-lactamase protein, via extracellular vesicles. These extracellular vesicles enabled other ampicillin-susceptible Gram-negative and Gram-positive bacteria to survive in the presence of ampicillin. However, S. aureus extracellular vesicles did not mediate the survival of tetracycline-, chloramphenicol-, or kanamycin-susceptible bacteria. Moreover, S. aureus extracellular vesicles did not contain the blaZ gene. In addition, the heat-treated S. aureus extracellular vesicles did not mediate the survival of ampicillin-susceptible bacteria. The β-lactamase activities of S. aureus soluble and extracellular vesicle-associated BlaZ were similar, but only the extracellular vesicle-associated BlaZ was resistant to protease digestion, which suggests that the enzymatic activity of BlaZ in extracellular vesicles is largely protected by the vesicle structure. Our observations provide evidence of the important role of S. aureus extracellular vesicles in antibiotic resistance, which allows the polymicrobial community to continue to evolve and prosper against antibiotics.

The aim of this study was to compare the activity of the erector spinae (ES) and hamstring muscles and the amount and onset of lumbar motion during standing knee flexion between individuals with and without lumbar extension rotation syndrome. Sixteen subjects with lumbar extension rotation syndrome (10 males, 6 females) and 14 healthy subjects (8 males, 6 females) participated in this study. During the standing knee flexion, surface electromyography (EMG) was used to measure muscle activity, and surface EMG electrodes were attached to both the ES and hamstring (medial and lateral) muscles. A three-dimensional motion analysis system was used to measure kinematic data of the lumbar spine. An independent-t test was conducted for the statistical analysis. The group suffering from lumbar extension rotation syndrome exhibited asymmetric muscle activation of the ES and decreased hamstring activity. Additionally, the group with lumbar extension rotation syndrome showed greater and earlier lumbar extension and rotation during standing knee flexion compared to the control group. These data suggest that asymmetric ES muscle activation and a greater amount of and earlier lumbar motion in the sagittal and transverse plane during standing knee flexion may be an important factor contributing to low back pain.