The auditory brainstem response (ABR) is a noninvasive test that measures neural activity in response to auditory stimuli. Racial differences in head shape have provided strong evidence for specific normative data and accurate device calibration. International standards emphasize the need for standardized procedures and references. This study aimed to outline the standard procedure and related normative ABR values. Standard procedures were performed according to International Electrotechnical Commission (IEC) standards. Five studies from two countries were included to compare the normative values of the ABR. The dataset from the National Standard Reference Data Center (NSRDC) was used as reference. Normative values were described in terms of stimuli, latency, and amplitude. For click stimuli, the latency of the ABR showed different patterns across populations, such as those from Korea and the USA. Although the latencies reported by the NSRDC and for Koreans were relatively short, those reported for USA populations were longer. Using clicks, it was shown that the USA population had the largest ABR amplitude compared to those reported for the other two datasets. For Wave V latency using tone bursts, a similar pattern was identified with click stimuli. Frequency-specific trends were also observed. Although there is a lack of ABR datasets, the information and insights of the present study could be utilized as standard guidelines in research on ABR.

Background: Exhaled condensates contain inflammatory biomarkers; however, their roles in the clinical field have been under-investigated. Methods: We prospectively enrolled subjects admitted to pulmonology clinics. We collected exhaled breath condensates (EBC) and analysed the levels of six and 12 biomarkers using conventional and multiplex enzyme-linked immunosorbent assay, respectively. Results: Among the 123 subjects, healthy controls constituted the largest group (81 participants; 65.9%), followed by the preserved ratio impaired spirometry group (21 patients; 17.1%) and the chronic obstructive pulmonary disease (COPD) group (21 patients; 17.1%). In COPD patients, platelet derived growth factor-AA exhibited strong positive correlations with COPD assessment test (ρ=0.5926, p=0.0423) and COPD-specific version of St. George’s Respiratory Questionnaire (SGRQ-C) score (total, ρ=0.6725, p=0.0166; activity, ρ=0.7176, p=0.0086; and impacts, ρ=0.6151, p=0.0333). Granzyme B showed strong positive correlations with SGRQ-C score (symptoms, ρ=0.6078, p=0.0360; and impacts, ρ=0.6007, p=0.0389). Interleukin 6 exhibited a strong positive correlation with SGRQ-C score (activity, ρ=0.4671, p=0.0378). The absolute serum eosinophil and basophil counts showed positive correlations with pro-collagen I alpha 1 (ρ=0.6735, p=0.0164 and ρ=0.6295, p=0.0283, respectively). In healthy subjects, forced expiratory volume in 1 second (FEV1)/forced vital capacity demonstrated significant correlation with CC chemokine ligand 3 (CCL3)/macrophage inflammatory protein 1 alpha (ρ=0.3897 and p=0.0068). FEV1 exhibited significant correlation with CCL11/eotaxin (ρ=0.4445 and p=0.0017). Conclusion Inflammatory biomarkers in EBC might be useful to predict quality of life concerning respiratory symptoms and serologic markers. Further studies are needed.

Background: Blastocystis is a genus of intestinal, anaerobic protozoan parasites that can be isolated from humans, animals, and the environment. We aimed to determine the distribution of Blastocystis and subtypes (STs) using stool samples obtained from healthy volunteers at collection centers in South Korea. Methods: A total of 478 stool samples from volunteers were collected at five collection centers throughout South Korea. The presence of Blastocystis was determined using PCR based on the small subunit (SSU) rRNA gene, and Blastocystis STs were confirmed through sequencing of the SSU rRNA gene. Results: Molecular analysis revealed the presence of Blastocystis in 27 (5.6%) of the enrolled participants. Two STs were identified: ST3 (66.7%) and ST1 (33.3%). The positive rates of Blastocystis varied by geographical region, ranging from 1.2%–12.0%. ST3 was the predominant subtype in all centers except one, where only ST1 was isolated. Phylogenic analysis showed clustering based on ST, but no significant differences were found among the regions. There was no association between Blastocystis colonization and either age or sex of the participants. Conclusions The results of this multicenter study demonstrated colonization by Blastocystis, mainly ST3, in the gastrointestinal tracts of asymptomatic individuals in South Korea.

Background: Although most studies focused on the alignment or union of the tibia in same-level distal third tibiofibular fractures, the outcome of a concomitant fibular fracture is generally regarded as being of secondary importance in the literature. This study aimed to assess the outcomes of fibular fractures in same-level distal third tibiofibular fractures. Methods: In this retrospective study, we enrolled 111 patients with same-level distal third tibiofibular fractures treated at our institute between January 2016 and August 2020. Tibial fractures were stabilized with intramedullary nailing, and the cases were divided into two groups based on whether they additionally underwent fibular fixation (group 1, 57 cases) or not (group 2, 54 cases). Clinical and radiographic outcomes were used for the evaluation of tibial and fibular alignments, union of the tibia and fibula, number of interlocking screws in the distal tibial fragment, range of motion of the ankle joint, and complications. Results: No statistically significant differences in the tibial union rate or mean tibial alignment were observed between the two groups on either the immediate postoperative or final radiographs. The fibular union rate in group 1 was significantly higher than that in group 2 (fibular nonunion, 0 vs. 15; p < 0.001). Statistically significant differences in fibular displacement were observed on immediate postoperative radiographs between patients with fibular union and those without it. At the final follow-up, the mean range of ankle motion and lower extremity functional scale scores did not differ between the two groups. Conclusions Regardless of whether fibular fixation was performed, the overall tibial alignment with intramedullary nailing was well restored and the union rate of the tibia was comparable in the two groups. Fibular nonunion is not uncommon in unfixed fibula fractures. Displacement of the fibula as seen on immediate postoperative radiographs was related to fibular nonunion.

Purpose: To establish a prospective registry for the active surveillance (AS) of prostate cancer (PC) using the Korean Urological Oncology Society (KUOS) database and to present interim analysis. Materials and Methods: The KUOS registry of AS for PC (KUOS-AS-PC) was organized in May 2019 and comprises multiple institutions nationwide. The eligibility criteria were as follows: patients with (1) pathologically proven PC; (2) pre-biopsy prostate-specific antigen (PSA) ≤20 ng/mL; (3) International Society of Urological Pathology (ISUP) grade 1 or 2 (no cribriform pattern 4); (4) clinical T stage ≤T2c; (5) positive core ratio ≤50%; and (6) maximal cancer involvement in the core ≤50%.Detailed longitudinal clinical information, including multi-parametric magnetic resonance imaging and disease-specific outcomes, was recorded. Results: From May 2019 to June 2021, 296 patients were enrolled, and 284 were analyzed. The mean±standard deviation (SD) age at enrollment was 68.7±8.2 years. The median follow-up period was 11.2 months (5.9–16.8 mo). Majority of patients had pre-biopsy PSA ≤10 ng/mL (91.2%), PSA density <0.2 ng/mL 2 (79.7%), ISUP grade group 1 (94.4%), single positive core (65.7%), maximal cancer involvement in the core ≤20% (78.1%), and clinical T stage of T1c or lower (72.9%). Fifty-two (18.3%) discontinued AS for various reasons. Interventions included radical prostatectomy (80.8%), transurethral prostatectomy (5.8%), primary androgen deprivation therapy (5.8%), radiation (5.8%), and focal therapy (1.9%). The mean±SD time to intervention was 8.9±5.2 months. The reasons for discontinuation included pathologic reclassification (59.6%), patient preference (25.0%), and radiologic reclassification (9.6%). Two (4.8%) patients with pathologic Gleason score upgraded to ISUP grade group 4, no biochemical recurrence. Conclusions The KUOS established a successful prospective database of PC patients undergoing AS in Korea, named the KUOS-AS-PC registry.

Sacrococcygeal teratoma is the most common congenital tumor in neonates, and is reported in approximately 1/35,000 to 1/40,000 live births. Oligodendroglioma is a rare central nervous system tumor that is usually found in the cerebral hemisphere of young and middle aged adults. When associated with a teratoma, it is mainly identified in ovarian teratoma in adolescents and adults. We describe a rare case of a preterm infant with oligodendroglioma in a mature sacrococcygeal teratoma. The male neonate was born at a gestational age of 30 weeks with a protruding mass in the sacrococcygeal region. Pelvic magnetic resonance imaging showed a sacrococcygeal teratoma of approximately 11 cm comprising fat components and skeletal structure, that extended from the anterior part of the sacrum to the abdominal cavity. Radical resection was performed at 36 days of age. Macroscopically, the resected intra-abdominal mass had the characteristics of a cystic lesion, and the intrapelvic mass was a predominantly solid mixed cystic-solid lesion. Histologically, this solid lesion in the intrapelvic mass was composed of mature glial tissue, which comprised as a proliferation of monotonous cells with small and round nuclei, surrounded by a perinuclear halo (“fried egg” appearance). Additionally, these cells were immunohistochemically positive for glial fibrillary acidic protein. These findings confirmed the diagnosis of oligodendroglioma in sacrococcygeal mature teratoma. After the treatment, no recurrence was observed during the follow-up period, and no additional intervention was required. However, the patient is undergoing treatment for voiding dysfunction caused by a neurogenic bladder.

Purpose: This study aimed to identify prognostic factors based on treatment outcomes for congenital diaphragmatic hernia (CDH) at a single-center and to identify factors that may improve these outcomes. Methods: Thirty-five neonates diagnosed with CDH between January 2011 and December 2021 were retrospectively analyzed. Pre- and postnatal factors were correlated and analyzed with postnatal clinical outcomes to determine the prognostic factors. Highest oxygenation index (OI) within 24 hours of birth was also calculated. Treatment strategy and outcome analysis of published literatures were also performed. Results: Overall survival rate of this cohort was 60%. Four patients were unable to undergo anesthesia and/or surgery. Three patients who commenced extracorporeal membrane oxygenation (ECMO) post-surgery were non-survivors. Compared to the survivor group, the non-survivor group had a significantly higher occurrence of pneumothorax on the first day, need for high-frequency ventilator and inhaled nitric oxide use, and high OI within the first 24 hours. The non-survivor group showed an early trend towards the surgery timing and a greater number of patch closures. Area under the receiver operating characteristic curve was 0.878 with a sensitivity of 76.2% and specificity of 92.9% at an OI cutoff value of 7.75. Conclusion OI within 24 hours is a valuable predictor of survival. It is expected that the application of ECMO based on OI monitoring may help improve the opportunity for surgical repair, as well as the prognosis of CDH patients.

Background/Aims: Efficient anti-fibrotic therapies are required for the treatment of liver cirrhosis. Hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) and cyclooxygenase-2 (COX-2) inhibitors have been reported to have anti-fibrotic effects. Here, we investigated whether combined treatment with a statin and a COX-2 inhibitor has synergistic anti-fibrotic effects. Methods: The effects of treatment strategies incorporating both simvastatin and a COX-2 inhibitor, NS-398, were investigated using an immortalized human hepatic stellate cell line (LX-2) and a hepatic fibrosis mouse model developed using thioacetamide (TAA) in drinking water. Cellular proliferation was investigated via 5-bromo-2-deoxyuridine uptake. Pro- and anti-apoptotic factors were investigated through Western blotting and real-time polymerase chain reaction analysis. Results: The evaluation of the anti-proliferative effects on LX-2 cells showed that the observed effects were more pronounced with combination therapy than with single-drug therapy. Moreover, hepatic fibrosis and collagen deposition decreased significantly in TAA-treated mice in response to the combined treatment strategy. The mechanisms underlying the anti-fibrotic effects of the combination therapy were investigated. The effects of the combination therapy were correlated with increased expression levels of extracellular signal-regulated kinase 1/2 signaling molecules, upregulation of the Bax/Bcl-2 signaling pathway, inhibition of the transforming growth factor-β signaling pathway, and inhibition of tissue inhibitor of matrix metalloproteinases 1 and 2. Conclusions The combination of simvastatin and NS-398 resulted in a synergistic anti-fibrotic effect through multiple pathways. These findings offer a theoretical insight into the possible clinical application of this strategy for the treatment of advanced liver diseases with hepatic fibrosis.

Background/Aims: Sorafenib is the first approved systemic treatment for advanced hepatocellular carcinoma (HCC). However, its clinical utility is limited, especially in Asian countries. Several reports have suggested the survival benefits of hepatic arterial infusion chemotherapy (HAIC) for advanced HCC with main portal vein tumor thrombosis (PVTT). This study aimed to compare the efficacy of sorafenib-based therapy with that of HAIC-based therapy for advanced HCC with main PVTT. Methods: Advanced HCC patients with main PVTT treated with sorafenib or HAIC between 2008 and 2016 at Korea University Medical Center were included. We evaluated overall survival (OS), time-to-progression (TTP), and the disease control rate (DCR). Results: Seventy-three patients were treated with sorafenib (n=35) or HAIC (n=38). Baseline characteristics were not significantly different between groups, except the presence of solid organ metastasis (46% vs 5.3%, p<0.001). The median OS time was not significantly different between the groups (6.4 months vs 10.0 months, p=0.139). TTP was longer in the HAIC group than in the sorafenib group (2.1 months vs 6.2 months, p=0.006). The DCR was also better in the HAIC group than in the sorafenib group (37% vs 76%, p=0.001). Subgroup analysis, which excluded patients with extrahepatic solid organ metastasis, showed the same trends for the median OS time (8.8 months vs 11.1 months, p=0.097), TTP (1.9 months vs 6.0 months, p<0.001), and DCR (53% vs 81%, p=0.030). Conclusions HAIC-based therapy may be an alternative to sorafenib for advanced HCC with main PVTT by providing longer TTP and a better DCR.

Background: Prognosis of patients with diverse chronic diseases is reportedly associated with 25-hydroxyvitamin D levels. In this study, we investigated the potential role of 25-hydroxyvitamin D3 (25[OH]D3) levels in improving the predictive power of conventional prognostic models for patients with liver cirrhosis. Methods: We investigated clinical findings, including serum 25(OH)D3 levels at admission, of 155 patients with cirrhosis who were followed up for a median of 16.9 months. Results: Median 25(OH)D3 levels were significantly different among patients exhibiting Child-Pugh grades A, B, and C. Mortality, including urgent transplantation, was significantly associated with 25(OH)D3 levels in univariate analysis. Severe vitamin-D deficiency (serum 25[OH]D3 level < 5.0 ng/mL) was significantly related to increased mortality, even after adjusting for Child-Pugh and Model for End-stage Liver Disease (MELD) scores. In particular, the presence of severe vitamin D deficiency clearly defined a subgroup with significantly poorer survival among patients with Child-Pugh scores of 5–10 or MELD scores ≤ 20. A new combination model of MELD score and severe vitamin D deficiency showed significantly more accurate predictive power for short- and long-term mortality than MELD scores alone. Additionally, serum 25(OH)D3 levels and new model scores were significantly associated with the development of spontaneous bacterial peritonitis, overt encephalopathy, and acute kidney injury. Conclusion Serum 25(OH)D3 level is an independent prognostic factor for patients with liver cirrhosis and has a differential impact on disease outcomes according to MELD and Child-Pugh scores.