Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

Background: Current international guidelines recommend against deep sedation as it is associated with worse outcomes in the intensive care unit (ICU). However, in Korea the prevalence of deep sedation and its impact on patients in the ICU are not well known. Methods: From April 2020 to July 2021, a multicenter, prospective, longitudinal, noninterventional cohort study was performed in 20 Korean ICUs. Sedation depth extent was divided into light and deep using a mean Richmond Agitation–Sedation Scale value within the first 48 hours. Propensity score matching was used to balance covariables; the outcomes were compared between the two groups. Results: Overall, 631 patients (418 [66.2%] and 213 [33.8%] in the deep and light sedation groups, respectively) were included. Mortality rates were 14.1% and 8.4% in the deep and light sedation groups (P = 0.039), respectively. Kaplan-Meier estimates showed that time to extubation (P < 0.001), ICU length of stay (P = 0.005), and death P = 0.041) differed between the groups. After adjusting for confounders, early deep sedation was only associated with delayed time to extubation (hazard ratio [HR], 0.66; 95% confidence inter val [CI], 0.55– 0.80; P < 0.001). In the matched cohort, deep sedation remained significantly associated with delayed time to extubation (HR, 0.68; 95% 0.56–0.83; P < 0.001) but was not associated with ICU length of stay (HR, 0.94; 95% CI, 0.79–1.13; P = 0.500) and in-hospital mortality (HR, 1.19; 95% CI, 0.65–2.17; P = 0.582). Conclusion In many Korean ICUs, early deep sedation was highly prevalent in mechanically ventilated patients and was associated with delayed extubation, but not prolonged ICU stay or in-hospital death.

Background: As the number of large-scale studies involving multiple organizations producing data has steadily increased, an integrated system for a common interoperable format is needed. In response to the coronavirus disease 2019 (COVID-19) pandemic, a number of global efforts are underway to develop vaccines and therapeutics. We are therefore observing an explosion in the proliferation of COVID-19 data, and interoperability is highly requested in multiple institutions participating simultaneously in COVID-19 pandemic research. Results: In this study, a laboratory information management system (LIMS) approach has been adopted to systemically manage various COVID-19 non-clinical trial data, including mortality, clinical signs, body weight, body temperature, organ weights, viral titer (viral replication and viral RNA), and multiorgan histopathology, from multiple institutions based on a web interface. The main aim of the implemented system is to integrate, standardize, and organize data collected from laboratories in multiple institutes for COVID-19 non-clinical efficacy testings. Six animal biosafety level 3 institutions proved the feasibility of our system. Substantial benefits were shown by maximizing collaborative high-quality non-clinical research. Conclusions This LIMS platform can be used for future outbreaks, leading to accelerated medical product development through the systematic management of extensive data from non-clinical animal studies.

PURPOSE: The aim of the current study is to assess the spectrum of genetic variation in the BRIP1 gene among Korean high-risk breast cancer patients who tested negative for the BRCA1/2 mutation. MATERIALS AND METHODS: Overall, 235 Korean patientswith BRCA1/2 mutation-negative high-risk breast cancerwere screened for BRIP1 mutations. The entire BRIP1 gene was analyzed using fluorescent-conformation sensitive gel electrophoresis. In silico analysis of BRIP1 variants was performed using PolyPhen-2 and SIFT. RESULTS: A total of 20 sequence alterations including 12 exonic and eight intronic variantswere found. Among the 12 exonic variants, 10 were missense and two were silent mutations. No protein-truncating mutation was found among the tested patients. Among the 10 missense variants, four (p.L263F, p.L340F, p.L474P, and p.R848H) were predicted to be pathogenic by both PolyPhen-2 and SIFT, and these variants were found in five patients. Of the four missense variants, p.L263F, p.L474P, and p.R848H localize to regions between the helicase motifs, while p.L340F resides in an iron-sulfur domain of BRIP1. CONCLUSION: No protein-truncating mutation in BRIP1 was found among the tested patients. The contribution of BRIP1 variants is thought to be minor in Korean non-BRCA1/2 high-risk breast cancer.
Breast Neoplasms* ; Breast* ; Computer Simulation ; Electrophoresis ; Exons ; Genetic Variation ; Hereditary Breast and Ovarian Cancer Syndrome ; Humans ; Introns ; Korea ; Silent Mutation

During a Korean mushroom diversity survey from 2011 to 2014, we found one new Xylaria species (X. ripicola sp. nov.) and one Xylaria species that had not been previously observed in Korea (X. tentaculata). To confirm the phylogenetic placement of the new species, we conducted a phylogenetic investigation based on internal transcribed spacer regions of ribosomal DNA sequences. Additionally, the new species, X. ripicola, was subsequently analyzed for RNA polymerase II subunit sequences. We also evaluated the macroscopic and microscopic features of this species. Herein, X. ripicola is described as a new species that was collected from a natural beach habitat and X. tentaculata is formally reported as newly found in Korea.
Agaricales ; Ascomycota ; Classification ; DNA, Ribosomal ; Ecosystem ; Korea* ; Phylogeny ; RNA Polymerase II

Anatomic variations in the biliary tree may not be detected until adulthood and they can cause unexplained jaundice and biliary pain. Recognition of these anatomic variations is important to avoid an incorrect diagnosis and significant ductal injury during biliary surgery. Although there are numerous anatomic bile duct variations, an accessory cystic duct draining into the right hepatic duct is rare. We report a case of an accessory cystic duct draining into the right hepatic duct with cholelithiasis, in which the abnormality was identified by endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography and confirmed by laparoscopic cholecystectomy.
Bile Ducts ; Biliary Tract ; Cholangiopancreatography, Endoscopic Retrograde ; Cholangiopancreatography, Magnetic Resonance ; Cholecystectomy, Laparoscopic ; Cholecystitis ; Choledocholithiasis ; Cholelithiasis ; Cystic Duct* ; Diagnosis ; Hepatic Duct, Common ; Jaundice

Pseudomembranous colitis (PMC) is a frequent cause of morbidity and mortality among hospitalized patients. Although diarrhea is the most common manifestation, PMC may be associated with intraperitoneal fluid accumulation in the severe cases. And a few cases showing both ascites and pleural effusion have been reported in patients with PMC. We report a case of PMC who showed elevated serum and ascites levels of carcinoembryonic antigen (CEA) with a normal CEA level in pleural effusion and who successfully recovered after oral administration of metronidazole. After treatment, the serum CEA level returned to the reference range.
Administration, Oral ; Ascites ; Carcinoembryonic Antigen* ; Diarrhea ; Enterocolitis, Pseudomembranous* ; Humans ; Metronidazole ; Mortality ; Pleural Effusion ; Reference Values

We conducted five times surveys, in June, September and October in 2012; June and September 2013, to catalog the mushroom flora in Ulleung-gun, Republic of Korea. More than 400 specimens were collected, and 317 of the specimens were successfully sequenced using the ribosomal DNA internal transcribed spacer barcode marker. We also surveyed the morphological characteristics of the sequenced specimens. The specimens were classified into 2 phyla, 7 classes, 21 orders, 59 families, 122 genera, and 221 species, and were deposited in the herbarium of Korea National Arboretum. Among the collected species, 72% were saprophytic, 25% were symbiotic, and 3% were parasitic. The most common order was Agaricales (189 specimens, 132 species), followed by Polyporales (47 specimens, 27 species), Russulales (31 specimens, 22 species), Boletales (10 specimens, 7 species), and so on. Herein, we also reported the first Bovista species in Korea, which was collected from Dokdo, the far-eastern island of Korea.
Agaricales* ; DNA, Ribosomal ; Humans ; Korea ; Polyporales ; Republic of Korea*

The successful treatment of community-acquired pneumonia requires appropriate, empirical antimicrobial therapy. The etiology and antimicrobial susceptibility of major pneumonia pathogens can differ by country. Therefore, the ideal treatment guidelines for community-acquired pneumonia should be based on the studies performed in each country. We developed a treatment guideline for community-acquired pneumonia for immunocompetent adults in Korea. This guideline was developed by the joint committee of the Korean Society for Chemotherapy, the Korean Society of Infectious Diseases, and the Korean Academy of Tuberculosis and Respiratory diseases.
Adult ; Anti-Bacterial Agents ; Communicable Diseases ; Humans ; Joints ; Korea ; Pneumonia ; Tuberculosis