Background/Aims: Although anti-hepatitis C virus (HCV) assay is widely used to screen for HCV infection, it has a high false-positive (FP) rate in low-risk populations. We investigated the accuracy of anti-HCV signal-to-cutoff (S/CO) ratio to distinguish true-positive (TP) from FP HCV infection. Methods: We retrospectively analyzed 77,571 patients with anti-HCV results. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic accuracy of anti-HCV S/CO ratio in anti-HCV positive patients. Results: Overall, 1,126 patients tested anti-HCV positive; 34.7% of patients were FP based on HCV RNA and/or recombinant immunoblot assay (RIBA) results. The age and sex-adjusted anti-HCV prevalence was 1.22%. We identified significant differences in serum aspartate transaminase and alanine transaminase levels, anti-HCV S/CO ratio, and RIBA results between groups (viremia vs. non-viremia, TP vs. FP). Using ROC curves, the optimal cutoff values of anti-HCV S/CO ratio for HCV viremia and TP were 8 and 5, respectively. The area under the ROC curve, sensitivity, specificity, positive and negative predictive values were 0.970 (95% CI, 0.959–0.982, p < 0.001), 99.7%, 87.5%, 87.4%, and 99.7%, respectively, for predicting HCV viremia at an anti-HCV S/CO ratio of 8 and 0.987 (95% CI, 0.980–0.994, p < 0.001), 95.3%, 94.7%, 97.1%, and 91.4%, respectively, for TP HCV infection at an anti-HCV S/CO ratio of 5. No patients with HCV viremia had an anti-HCV S/CO ratio below 5. Conclusions The anti-HCV S/CO ratio is highly accurate for discriminating TP from FP HCV infection and should be considered when diagnosing HCV infections.

Acarosporaceae is a crustose lichen and is known as a species that has more than 50 multispores, and has hyaline spores. Those taxa are often found in rock and soil in mountain areas or coastal regions in Korea, and very diverse forms and species are known. However, after an overall genetic phylogenetic analysis of carbonized ascomata in 2015, species consisting only of the morphological base are newly divided, and several species of Acarosporaceae in Korea are also being discovered in this situation. As a result of analysis using internal transcribed spacer (ITS) and nuLSU gene analysis, Korean species belonged to Acarospora and Sarcogyne clade, and i>Acarospora classified as the Acarospora clade was mixed with the Polysporina group and the Sarcogyne clade is mixed with the Acarospora. We identified two new species (Acarospora beangnokdamensis J. S. Park & S. O. Oh, sp. nov., Sarcogyne jejuensis J. S. Park & S. O. Oh, sp. nov.) through morphological, molecular, and secondary metabolite substance and found one new record (Sarcogyne oceanica K. Knudsen & Kocourk). We have made a classification key forAcarospora and Sarcogyne in Korea and reported all information together here.

Lecanora is one of the largest genera of lichens worldwide. These lichens can be easily seen, and are commonly found on trees and rocks. Most Korean Lecanora species belong to the Lecanora subfusca group, which has well-defined superficial thallus, red–brown apothecia, and soredia. The new species of L. neobarkmaniana grows on rocks, farinose soredia coalescing, usually covering the whole thallus, and containing atranorin and zeorin. We used internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequence data to identify the phylogenetic relationship across Lecanora sequence data and found the species to form different clades. In this study, we reported some interesting findings and described the genetic relationship with other sorediate Lecanora species and the characteristics of the new species. An identification key for the Korean sorediate Lecanoraspecies is given.

Background: Tenofovir disoproxil fumarate (TDF, Viread® ) had been used as a standard treatment option of chronic hepatitis B (CHB). This clinical trial was conducted to evaluate the efficacy and safety of DA-2802 (tenofovir disoproxil orotate) compared to TDF. Methods: The present study was a double blind randomized controlled trial. Patients with CHB were recruited from 25 hospitals in Korea and given DA-2802 at a dose of 319 mg once daily or Viread® at a dose of 300 mg once daily for 48 weeks from March 2017 to January 2019. Change in hepatitis B virus (HBV) DNA level at week 48 after dosing compared to baseline was the primary efficacy endpoint. Secondary efficacy endpoints were proportions of subjects with undetectable HBV DNA, those with normal alanine aminotransferase (ALT) levels, and those with loss of hepatitis B envelop antigen (HBeAg), those with loss of hepatitis B surface antigen (HBsAg). Adverse events (AEs) were also investigated. Results: A total of 122 patients (DA-2802 group: n = 61, Viread® group: n = 61) were used as full analysis set for efficacy analysis. Mean age, proportion of males, laboratory results and virologic characteristics were not different between the two groups. The change in HBV DNA level at week 48 from baseline was −5.13 ± 1.40 in the DA-2802 group and −4.97 ± 1.40 log 10 copies/mL in the Viread® group. The analysis of primary endpoint using the nonparametric analysis of covariance showed statistically significant results (P < 0.001), which confirmed non-inferiority of DA-2802 to Viread® by a prespecified noninferiority margin of 1. The proportion of undetectable HBV DNA was 78.7% in the DA-2802 group and 75.4% in the Viread® group (P = 0.698). The proportion of subjects who had normal ALT levels was 75.4% in the DA-2802 group and 73.3% in the Viread® group (P = 0.795). The proportion of those with HBeAg loss was 8.1% in the DA-2802 group and 10.8% in the Viread® group (P = 1.000). No subject showed HBsAg loss. The frequency of AEs during treatment was similar between the two groups. Most AEs were mild to moderate in severity. Conclusion DA-2802 is considered an effective and safe treatment for patients with CHB.

OBJECTIVE: Patients suspected as having acute ischemic stroke usually undergo blood tests, including coagulation-related indexes, because thrombocytopenia and coagulopathy are contraindications for recombinant tissue plasminogen activator (rtPA) administration. We aimed to identify blood test indexes associated with symptomatic intracranial hemorrhage (sICH) in patients with acute ischemic stroke who received intravenous rtPA.METHODS: This retrospective observational study included patients diagnosed with acute ischemic stroke who were treated with intravenous rtPA at the emergency department of a tertiary hospital in Seoul between February 2008 and January 2018. Blood test indexes were compared between the sICH and non-sICH groups. Logistic regression and receiver-operating characteristic curve analyses were performed.RESULTS: In this study, 375 patients were finally included. Of 375 patients, 42 (11.2%) showed new intracranial hemorrhage on follow-up brain computed tomography, of whom 14 (3.73%) had sICH. Platelet count, aspartate aminotransferase and lactate dehydrogenase levels were significantly different between the sICH and non-sICH groups, and platelet count showed statistical significance in the regression analysis. Significantly lower platelet counts were observed in the sICH group than in the non-sICH group (174,500 vs. 228,000/mm³, P=0.020). The best cutoff platelet count was 195,000/mm³, and patients with platelet counts of < 195,000/mm³ had a 5.4- times higher risk of developing sICH than those with platelet counts of ≥195,000/mm³.CONCLUSION: Platelet count was the only independent parameter associated with sICH among the blood test indexes. Mild thrombocytopenia may increase the risk of sICH after intravenous administration of rtPA.
Administration, Intravenous ; Aspartate Aminotransferases ; Brain ; Cerebral Infarction ; Emergency Service, Hospital ; Follow-Up Studies ; Hematologic Tests ; Humans ; Intracranial Hemorrhages ; L-Lactate Dehydrogenase ; Logistic Models ; Observational Study ; Platelet Count ; Retrospective Studies ; Seoul ; Stroke ; Tertiary Care Centers ; Thrombocytopenia ; Thrombolytic Therapy ; Tissue Plasminogen Activator

OBJECTIVE: The UE Video Stylet VL400-S2 (UE Medical Devices, Newton, MA, USA) and Ambu aScope (Ambu, Copenhagen, Denmark) were recently introduced rigid video stylets and single-use fiberoptic bronchoscopes, respectively. To compare the utility of the two sets of equipment, this study conducted a randomized cross-over study using a manikin. METHODS: Twenty-eight novice doctors performed tracheal intubation on an airway trainer manikin (Laerdal, Stavanger, Norway). The sequence of intubation devices was randomized. The following data were measured and recorded: time to complete tracheal intubation (primary end point), overall success rate, time to see the glottis, and time to tube passage. RESULTS: The video stylet (24 seconds; interquartile range [IQR] 18–36) showed a significantly shorter completion time of the tracheal intubation than the fiberoptic bronchoscope (43 seconds; IQR, 32–84) (P<0.001). The overall success rate of tracheal intubation was 96.4% (27/28) in the video stylet and 82.1% (23/28) in the fiberoptic bronchoscope, and the cumulative success rate over time to complete intubation was significantly higher in the video stylet (P<0.001). CONCLUSION: The video stylet was superior to the fiberoptic bronchoscope in terms of the time to complete and the cumulative success rate of intubation for novice operators in manikin model. Further research will be needed to determine the degree of education required to use fiberoptic bronchoscopy.
Bronchoscopes ; Bronchoscopy ; Cross-Over Studies ; Education ; Glottis ; Intubation ; Intubation, Intratracheal ; Manikins ; Microscopy, Video

OBJECTIVE: This study examined whether the depth of chest compression (CC) recommended by current cardiopulmonary resuscitation guidelines is equally appropriate to both men and women. METHODS: Retrospective analysis of the chest computed tomography (CT) findings was performed. The anteroposterior diameter (APD), internal compressible depth (ICD), and anterior chest wall thickness were measured at the midpoint of the lower half of the sternum. The residual diameter (RD) for simulated CC was also obtained. If the RD was less than 20 mm, it was assumed that a potential injury would occur. RESULTS: A total of 319 adults (173 men, 141 women), who underwent chest CT at the emergency room, were enrolled. A statistically significant difference was observed between the mean APD and ICD between men and women. The mean APD and IPD were 8 mm shorter and 9.5 mm shorter, respectively, in women than in men. When adjusted for age, height, weight, and body mass index (BMI), the differences in the value of these parameters increased even more. In simulated CC with a 60 mm depth, the predictors of RD of less than 20 mm were weighed (odds ratio [OR], 0.888; 95% confidence interval [CI], 0.826–0.954; P=0.001) and BMI (OR, 0.706; 95% CI, 0.579–0.862; P=0.001), and all cases with RD of less than 20 mm were women. CONCLUSION: Chest compression of more than 60 mm may increase the potential risk of injury, particularly in women. The maximum allowable chest compression depth of less than 60 mm should be emphasized for women.
Adult ; Body Mass Index ; Cardiopulmonary Resuscitation ; Emergency Service, Hospital ; Female ; Humans ; Male ; Retrospective Studies ; Sternum ; Thoracic Wall ; Thorax ; Tomography, X-Ray Computed

During the 2014 survey of the mushroom flora of Gwangneung forest in South Korea, we collected two specimens of boletoid mushroom growing on a felled tree of Pinus koraiensis. These specimens were characterized by a light brown to reddish-brown pileus with appressed tomentum, pore surface bluing instantly when bruised, golden-yellow mycelium at the base of stipe, and lignicolous habitat. Both specimens were identified as Buchwaldoboletus lignicola, a rare basidiomycete, based on morphological characteristics and sequences of internal transcribed spacer (ITS; fungal barcode). Here, we describe these specimens and provide the first report of this genus in South Korea.

The Tian Shan mountain system is one of the large mountain ranges located in Central Asia. This region is globally recognized as mountain ranges, offering inestimable wealth in fauna and flora with significant biodiversity values. We surveyed macrofungal diversity of Tian Shan in Kyrgyzstan from 2016 to 2018. A collection of macrofungi was made, and these were subjected to sequence comparisons and phylogenetic analysis to ensure the identity of the collected macrofungi. Of those collected, 95 out of 100 specimens were successfully sequenced and compared with those of other related species retrieved from GenBank. The sequenced specimens were classified into 2 phyla, 8 orders, 24 families, 47 genera, and 57 species, based on current taxonomic concepts (combining morphology and phylogeny). To the best of our knowledge, this study provides the first well-documented checklist and phylogenetic analysis of macrofungi recovered from the Tian Shan mountains in Kyrgyzstan.

Arthonia dokdoensis sp. nov., a lichenicolous fungus from the subcosmopolitan Arthonia molendoi complex growing on crustose thalli of species of the genus Orientophila (subfamily Xanthorioideae, Teloschistaceae), as well as the lichen species Rufoplaca toktoana sp. nov. (subfamily Caloplacoideae, Teloschistaceae) similar to Rufoplaca kaernefeltiana, both from Dokdo Islands, Republic of Korea, are described, illustrated, and compared with closely related taxa. In the phylogenetic tree of the Arthoniaceae based on 12S mtSSU and RPB2 gene sequences, the phylogenetic position of the A. dokdoensis and the relationship with the A. molendoi group are illustrated, while the position of the newly described R. toktoana is confirmed by phylogenetic tree based on ITS nrDNA data.