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Background Even though Korea was known to have the highest number of coronavirus disease-2019 (COVID-19) infection in the early phase of the pandemic, Korea was able to successfully flatten the curve in a short period of time without extreme measures. We compared the status of cancer management before and after COVID-19 and analysed how cancer care continuity was maintained in Korea. Patients and methods We investigated the medical records on the number of cancer diagnosis, cancer surgery, radiation therapy and scheduled chemotherapy conducted in Korea University Anam Hospital from January 1 to April 30, 2019 and from the same period in 2020. We also collected the data of metastatic cancer patients who were hospitalised due to respiratory disease. Results Of all diagnoses, 1694 cancer diagnoses were made in the study period of 2019, and 1445 diagnoses in 2020 (decreased by 14.7%); the cancer surgery performed 830 and 800 cases; the set-up for radiation therapy decreased from 185 to 140 cases; the number of systemic chemotherapies for metastatic cancer patients treated in department of medical oncology increased from 2555 to 2878 cases. Among hospitalised patients, emergency centre visit, intensive care unit admission, discharge after recovery and death reveal no drastic changes. Conclusions Routine cancer care for patients with metastatic cancer has been maintained without significant difference before and after the COVID-19 pandemic. The Korean government's innovative countermeasures in the early phase of outbreak made it possible for cancer care practitioners to provide cancer patients with regular care under the standard infection control protocol., Highlights • Routine cancer care has been maintained before and after the coronavirus disease-2019 pandemic. • The Korean government's innovative countermeasures were important. • Information provided will help you understand public health in pandemic times.

Background While herd effects and serotype replacement by childhood pneumococcal protein conjugated vaccines (PCVs) continues to accumulate worldwide, direct effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPV23) against pneumococcal diseases in the elderly has been challenged. We estimated the direct effectiveness of PPV23 in the elderly population. Methods For a hospital-based case-control study, cases of invasive pneumococcal disease (IPD) and non-bacteremic pneumococcal pneumonia (NBPP) (adults ≥ 65 years) were identified in 14 hospitals participated in the pneumococcal surveillance program from March 2013 to October 2015, following implementation of PPV23 national immunization program (NIP) for the elderly in the Republic of Korea. Controls matched by age, sex, and hospital were selected at ratios of 1:2 (IPD) or 1:1 (NBPP). Clinical data and vaccination records were collected. Vaccine effectiveness was calculated as (1-adjusted odds ratio) × 100. Results We enrolled 148 IPD and 557 NBPP cases, and 295 IPD and 557 NBPP controls for analyses. Overall effectiveness of PPV23 against IPD was 28.5% [95% confidence interval (CI) −5.8%–51.6%] and against NBPP was 10.2% (-15.1-30.6) in all patients ≥ 65 years. However, in subgroup analysis of patients aged 65–74 years, PPV23 was protective against IPD [effectiveness 57.4% (19.4–77.5)] and against NBPP [effectiveness 35.0% (2.3–56.7)]. Furthermore, serotype-specific effectiveness of PPV23 against IPD was 90.6% (27.6–98.8) for PPV23-unique serotypes and 81.3% (38.6–94.3) for PPV23 serotypes excluding serotype 3. Conclusions This study indicates that PPV23 with broad serotype coverage might be beneficial in preventing IPD and NBPP due to non-PCV13 serotypes in the young-elderly, with potentially increasing effectiveness in the setting of childhood PCV NIP.

Objectives: This study aimed to characterize the risk factors for mortality in adult patients with invasive pneumococcal disease (IPD) stratified by age groups, after implementation of the national immunization program of 23-valent polysaccharide vaccine (PPSV23) for those aged ≥65 years in the Republic of Korea (ROK). Methods: Clinical data and pneumococcal isolates from adult patients with IPD (≥18 years of age) were collected prospectively from 20 hospitals through the nationwide surveillance program from March 2013 to October 2015. Results: A total of 319 patients with IPD were enrolled. Median age was 69 years. Overall in-hospital mortality was 34.2%: 17.1% in those aged 18–49 years, 23.7% in those aged 50–64 years, 33.0% in those aged 65–74 years, and 51.0% in those aged ≥75 years (p

This study was conducted to investigate the epidemiology and antimicrobial susceptibility patterns of Gram-negative bacilli (GNB) isolated from intra-abdominal infections (IAIs) in the Asia-Pacific region (APR) from 2010-2013. A total of 17 350 isolates were collected from 54 centres in 13 countries in the APR. The three most commonly isolated GNB were Escherichia coli (46.1%), Klebsiella pneumoniae (19.3%) and Pseudomonas aeruginosa (9.8%). Overall, the rates of extended-spectrum β-lactamase (ESBL)-producing E. coli and K. pneumoniae were 38.2% and 24.3%, respectively, and they were highest in China (66.6% and 38.7%, respectively), Thailand (49.8% and 36.5%, respectively) and Vietnam (47.9% and 30.4%, respectively). During 2010-2013, the rates of ESBL-producing E. coli and K. pneumoniae isolates causing community-associated (CA) IAIs (collected48 h after admission) were 26.0% and 13.5%, respectively, and those causing hospital-associated (HA) IAIs were 48.0% and 30.6%, respectively. Amikacin, ertapenem and imipenem were the most effective agents against ESBL-producing isolates. Piperacillin/tazobactam displayed good in vitro activity (91.4%) against CA ESBL-producing E. coli. For other commonly isolated Enterobacteriaceae, fluoroquinolones, cefepime and carbapenems exhibited better in vitro activities than third-generation cephalosporins. Amikacin possessed high in vitro activity against all GNB isolates (80%) causing IAIs, except for Acinetobacter calcoaceticus-baumannii (ACB) complex (30.9% for HA-IAI isolates). All of the antimicrobial agents tested exhibited45% in vitro activity against ACB complex. Antimicrobial resistance is a persistent threat in the APR and continuous monitoring of evolutionary trends in the susceptibility patterns of GNB causing IAIs in this region is mandatory.

Background Endogenous fungal endophthalmitis (EFE) is a critical complication of candidemia. We conducted a study to investigate the prevalence and risk factors for EFE. Methods Adult candidemia patients ≥ 19 years who underwent an ophthalmological examination at a tertiary care hospital in the Republic of Korea from 2006 to 2018 were enrolled. Results There was a total of 152 adult candidemia patients analyzed. EFE was found in 29 patients (19.1%). Patients were categorized into two groups (Non-endophthalmitis [NE] and endophthalmitis [E]). Between the two groups, there was no significant difference in terms of age, sex, and underlying comorbidities. However, there were more Candida albicans candidemia, abnormal alanine aminotransferase (ALT) at the time of candidemia diagnosis, receipt of antifungal treatment ≥ 48 hours after onset of candidemia symptoms and blood culture sample (AOCS), and candidemia clearance ≥ 5 days after initiation of antifungal treatment (AIAT) in the E group. A predictive model for the E was created, which had an area of 0.811 under the receiver operating characteristics curve. In a multivariate logistic regression analysis, C. albicans candidemia, ALT at the time of candidemia diagnosis, receipt of antifungal treatment ≥ 48 hours AOCS, and candidemia clearance ≥ 5 days AIAT were significantly associated with EFE. Conclusion EFE occurred in 19% of adult patients with candidemia. Adult candidemia patients with C. albicans candidemia, abnormal ALT, receipt of antifungal treatment ≥ 48 hours AOCS, and candidemia clearance ≥ 5 days AIAT need to be closely monitored for the possibility of EFE.

Highlights • The current status of individual hospital-based infection prevention and control programs in the Republic of Korea is variable. • More specialist personnel and single rooms are necessary to achieve effective infection prevention and control. • Sensible policy support is also required for extensive program implementation., Background There is significant variability in personnel and infrastructural resources for infection prevention and control (IPC) among health care institutions. The aim of this study is to evaluate the current status of individual hospital-based IPC programs in the Republic of Korea (ROK). Methods A multicenter cross-sectional survey of 100 hospitals participating in the national surveillance programs for multidrug-resistant organisms (MDROs) in the ROK was conducted in September 2015. The survey consisted of 140 standardized Web-based questionnaires. Results The survey response rate was 41.0%. The responding hospitals are largely organized with multibed rooms, with an insufficient numbers of single rooms. Employment status of infection specialists and hand hygiene resources were better in larger hospitals. The responding hospitals had 1 full-time infection control nurse per 400.3 ± 154.1 beds, with wide variations in training and experience. Facilities have great diversity in their approach to preventing MDROs. There appeared to be no difference in supplies consumption and protocols for IPC among the hospitals, stratified according to size. Conclusions A greater availability of specialist personnel, single rooms, and a comprehensive IPC program, with the support of a policy-oriented management, is necessary to achieve effective IPC.

Summary Objectives To assess the safety and immunogenicity of a meningococcal polysaccharide diphtheria toxoid conjugate vaccine (MenACYW–D) in a Korean population. Methods This was a phase III, blind-observer, controlled study in which participants aged 11–55 years were randomized (2:1 ratio) to a single dose of MenACYW–D or tetanus/diphtheria/acellular pertussis (Tdap) vaccine. Outcomes included rates of seroconversion against all serogroups (≥4-fold increase in antibody titer from pre-vaccination), geometric mean titers (GMTs) at days 0 and 28 based on a serum bactericidal assay using baby rabbit complement, rates of seroprotection (titer ≥1:128) at day 28, and safety. Results A total of 300 participants were enrolled in the study (200 MenACYW–D and 100 Tdap). Seroconversion rates for serogroups A, C, Y, and W-135 were 77.8%, 88.3%, 74.6%, and 92.4%, respectively, for the MenACYW–D group and 9.3%, 8.1%, 12.2%, and 8.2%, respectively, for the Tdap group. The proportions of participants with pre-vaccination titers ≥1:128 were 57.3%, 12.6%, 51.5%, and 22.2% for serogroups A, C, Y, and W-135, respectively; post-vaccination rates were 98.5%, 89.4%, 96.0%, and 95.0% for the MenACYW–D group. A lower proportion of participants reported solicited reactions with MenACYW–D (46.2%) compared with Tdap (76.8%). Conclusion A single dose of MenACYW–D was well tolerated and elicited a robust immune response in Korean adolescents and adults.

Legionella pneumophila serogroup 1 (sg1) accounts for the majority of infections in humans, but other Legionella species are also associated with human disease. In this study, a new SYBR Green I-based multiplex real-time PCR assay in a single reaction was developed to allow the rapid detection and differentiation of Legionella species by targeting specific gene sequences. Candidate target genes were selected, and primer sets were designed by referring to comparative genomic hybridization data of Legionella species. The Legionella species-specific groES primer set successfully detected all 30 Legionella strains tested. The xcpX and rfbA primers specifically detected L. pneumophila sg1-15 and L. pneumophila sg1, respectively. In addition, this assay was validated by testing clinical samples and isolates. In conclusion, this novel multiplex real-time PCR assay might be a useful diagnostic tool for the rapid detection and differentiation of Legionella species in both clinical and epidemiological studies.

An ultrasensitive electrochemical immunosensor based on a ZnO nanorod (NR) matrix electrode was developed for detecting Legionella pneumophila for the first time. The ZnO NR matrix electrode was grown on an underlying Au working electrode (dia. 1.6 mm) using a hydrothermal method at a low temperature. A sandwich enzyme-linked immunosorbent assay was performed using the fabricated immunosensor. A primary antibody (1–4 μg/mL) was immobilized onto the ZnO NR matrix electrode by electrostatic interaction and the peptidoglycan-associated lipoprotein of L. pneumophila , as a component of Legionella antigen (1–5000 pg/mL) was bound to the primary antibody. A secondary antibody (1–4 μg/mL) conjugated to horseradish peroxidase was then bound to the antigen. The fabricated immunosensor was evaluated in a 0.1 M acetate buffer (pH 5) containing 0.05 mM 3,3′,5,5′-tetramethylbenzidine and 1 mM H 2 O 2 by cyclic voltammetry. In the fabricated immunosensors based on 1 μg/mL and 2 μg/mL antibody concentrations, the current output logarithmically increased with the L. pneumophila antigen concentrations from 1 to 5000 pg/mL. The detection limit is ∼1 pg/mL ( S / N = 4) with excellent selectivity.

Liposuction is the most widely performed cosmetic procedure in the world, and is considered safe and without serious complications. However, necrotising fasciitis has been documented as a rare complication following abdomen and thigh liposuction. We present a case of necrotising fasciitis in a 22-year-old female who underwent cosmetic liposuction in both calves. The diagnosis of necrotising fasciitis was delayed, leading to multi-organ dysfunction and skin necrosis with consequent massive skin loss. Non-cosmetic physicians are generally unfamiliar with liposuction-induced complications, and may not suspect necrotising fasciitis due to its rarity. However, awareness of its clinical features is critical since early diagnosis and prompt surgical debridement can prevent significant morbidity and even death.

An electrochemical immunosensor based on patterned plasma-functionalized multiwalled carbon nanotubes (pf-MWCNTs) working electrode for Legionella pneumophila detection is described in this paper. Polyclonal antibody was immobilized using passive adsorption and covalent immobilization on the surface of the pf-MWCNTs. Various dilutions of Legionella 19-kDa peptidoglycan-associated lipoprotein (PAL) were added onto the electrode surface and incubated. The assay was then completed using polyclonal antibody conjugated to horseradish peroxidase (HRP) as the enzyme label. 3,3',5,5'-Tetramethylbenzidine dihydrochloride (TMB)/substrate solution (H2O2) was used as the mediator/substrate system. Electrochemical detection was conducted using cyclic voltammetric at 500 mV versus silver/silver chloride (Ag/AgCl) reference electrode. L pneumophila detection of 0.16 ng ml(-1) and similar to 0.0025 ng ml(-1) was achieved respectively for passive adsorption and covalent immobilization. (C) 2010 Elsevier B.V. All rights reserved.

Summary Objectives To evaluate the clinical outcome and predictive factors of recurrence among patients with Kikuchi's disease. Methods Between January 2001 and December 2006, all patients with Kikuchi's disease were included in the study. Data were collected on co-morbidities, clinical manifestations, and ultrasound/laboratory findings, and the differences were compared between recurrent disease and non-recurrent disease groups. Results The study included 102 patients with a mean age of 26.7 years. Among these patients, three developed systemic lupus erythematosus during the follow-up period, while two cases were later associated with tuberculosis. Eight patients (7.8%) experienced early relapse and 13 (12.7%) showed late recurrence. Patients with recurrent episodes were more likely to have fever and fatigue with extranodal involvement. Compared to the non-recurrent cases, recurrent cases remained symptomatic for a rather longer duration. The positive rate of the fluorescence anti-nuclear antibody (FANA) test was significantly higher in the recurrent disease group compared to the non-recurrent disease group. Conclusions Kikuchi's disease took a self-limiting clinical course in most cases, but the recurrence rate found in the present study was higher than that of previous reports. Kikuchi's disease might be a phenotype of diverse disease entities. The prognosis is different according to the underlying cause. The FANA test would be useful in predicting recurrence.

A photometric immunosensor that can be used for on-site diagnosis has been constructed. The sensor system was assembled by partially superimposing a nitrocellulose membrane strip (the lower) containing an immobilized antigen on the surface with a glass fiber membrane strip (the upper) including two electrodes on the opposite surfaces. To amplify the signal, we introduced a liposome, containing ruthenium molecules trapped in the core, chemically coupled to an antibody specific to the analyte (e.g. Legionella antigen). In the presence of the analyte, immune complexes were formed by antigen-antibody reactions upon addition of the immuno-liposome into a sample. This mixture was then absorbed by the capillary action from the bottom of the membrane strip. The liposome particles in the complexes were carried by a medium through the antigen pad without interaction, while free immuno-liposome was trapped by immune reactions on the pad surfaces. The aqueous medium influx into the glass pad dissolved a detergent pre-located within the compartment and the liposome rupture thereby released ruthenium molecules into the solution. The molecules were oxidized on the electrode surfaces and produced an electro-chemiluminescence (ECL) in proportion to the analyte concentration. The signal generation based on ECL resulted in an exponential dose-response pattern and the analyte detection limit of 2 ng/ml was approximately 10-fold more sensitive than that obtained from a conventional system.

In a national sample of high school students, 43 per cent had drunk regularly, 32 per cent had smoked regularly, and 11 per cent had experienced sexual intercourse. Boys were more likely to have experienced these behaviors than girls. Going to school in Seoul, not having two parents in the family, and having an experience of living away from immediate family were associated with higher livelihood of experiencing these behaviors. Students who had friends with sexual experiences were much more likely to experience sex themselves than those without.

Microbial phosphatases are known or suspected to play a role in the pathogenesis of several intracellular pathogens, including Legionella micdadei. Legionella pneumophila also possess phosphatase activities, but their possible roles in cellular infection are unknown. We generated mutants of a serogroup 1 isolate of L. pneumophila that lack the major phosphatase. Isolation of a Pho- mutant after random mutagenesis with transposon MudII4041 allowed us to dissociate the major alkaline phosphatase (pH optimum approximately 8) from a minor acid phosphatase activity. Both activities were concentrated in the bacterial periplasm. The gene encoding the major alkaline phosphatase (pho) was cloned by expression in E. coli and used to generate a site directed mutation in two L. pneumophila strains. Each parent-mutant pair was compared in a U937 cell tissue culture assay for capacity to infect, lyse, and grow within mammalian cells. Although the parental stains differed in their U937 cell cytopathicity, neither was significantly more infective than its Pho- derivative, suggesting that the alkaline phosphatase activity is not essential for cellular infection. Because they are not attenuated, Pho- mutants can be used to generate gene fusions with E. coli alkaline phosphatase to study and secretion and cellular infectivity in L. pneumophila.

High-quality GaN nanowires have been synthesized by applying the laser ablation method. FE-SEM, XRD, HR-TEM, and EDX measurements show that the GaN nanowires are single crystals prepared through the vapor-liquid-solid growth mechanism. The light emitting devices (LEDs) with the structure of ITO-coated glass/PEDOT:PSS/GaN nanowire-PVK nanocomposites/DCM-doped Alq 3 /Li:Al have been fabricated and examined together with the investigations of luminescence and device characteristics.

We have fabricated and characterized novel organic electroluminescent devices based on a single-walled carbon nanotube (SWCNT)-2-(4-biphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (PBD) nanocomposite. Studies of luminescence and device characteristics demonstrate that as the fraction of SWCNTs in the PBD medium increases in the range of 0-1.0 wt%, the device performances such as external quantum efficiency (EQE) are significantly improved by a factor of 3 to 4 due to the efficient electron transport through highly conductive nanotubes.