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: Over the last decade, extracorporeal membrane oxygenation (ECMO) use in critically ill children has increased and is associated with favorable outcomes. Our study aims to evaluate the current status of pediatric ECMO in Korea, with a specific focus on its volume and changes in survival rates based on diagnostic indications. Methods: This multicenter study retrospectively analyzed the indications and outcomes of pediatric ECMO over 10 years in patients at 14 hospitals in Korea from January 2012 to December 2021. Four diagnostic categories (neonatal respiratory, pediatric respiratory, postcardiotomy, and cardiac-medical) and trends were compared between periods 1 (2012–2016) and 2 (2017–2021). Results: Overall, 1065 ECMO runs were performed on 1032 patients, with the annual number of cases remaining unchanged over the 10 years. ECMO was most frequently used for post-cardiotomy (42.4%), cardiac-medical (31.8%), pediatric respiratory (17.5%), and neonatal respiratory (8.2%) cases. A 3.7% increase and 6.1% decrease in pediatric respiratory and post-cardiotomy cases, respectively, were noted between periods 1 and 2.Among the four groups, the cardiac-medical group had the highest survival rate (51.2%), followed by the pediatric respiratory (46.4%), post-cardiotomy (36.5%), and neonatal respiratory (29.4%) groups. A consistent improvement was noted in patient survival over the 10 years, with a significant increase between the two periods from 38.2% to 47.1% (P = 0.004). Improvement in survival was evident in post-cardiotomy cases (30–45%, P = 0.002).Significant associations with mortality were observed in neonates, patients requiring dialysis, and those treated with extracorporeal cardiopulmonary resuscitation (P < 0.001). In pediatric respiratory ECMO, immunocompromised patients also showed a significant correlation with mortality (P < 0.001). Conclusion Pediatric ECMO demonstrated a steady increase in overall survival in Korea;however, further efforts are needed since the outcomes remain suboptimal compared with global outcomes.

Purpose: Alzheimer’s disease (AD) dementia may not be a single disease entity. Early-onset AD (EOAD) and late-onset AD (LOAD) have been united under the same eponym of AD until now, but disentangling the heterogeneity according to the age of sonset has been a major tenet in the field of AD research. Materials and Methods: Ninety-nine patients with AD (EOAD, n=54; LOAD, n=45) and 66 cognitively normal controls completed both [18F]THK5351 and [18F]flutemetamol (FLUTE) positron emission tomography scans along with structural magnetic resonance imaging and detailed neuropsychological tests. Results: EOAD patients had higher THK retention in the precuneus, parietal, and frontal lobe, while LOAD patients had higher THK retention in the medial temporal lobe. Intravoxel correlation analyses revealed that EOAD presented narrower territory of local FLUTE-THK correlation, while LOAD presented broader territory of correlation extending to overall parieto-occipito-temporal regions. EOAD patients had broader brain areas which showed significant negative correlations between cortical thickness and THK retention, whereas in LOAD, only limited brain areas showed significant correlation with THK retention. In EOAD, most of the cognitive test results were correlated with THK retention. However, a few cognitive test results were correlated with THK retention in LOAD. Conclusion LOAD seemed to show gradual increase in tau and amyloid, and those two pathologies have association to each other. On the other hand, in EOAD, tau and amyloid may develop more abruptly and independently. These findings suggest LOAD and EOAD may have different courses of pathomechanism.

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.

Cotinine ; Daegu ; Firefighters ; Fires ; Humans ; Male ; Sensitivity and Specificity ; Smoke ; Smoking ; Tobacco Use

BACKGROUND: In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters. METHODS: This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results. RESULTS: The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease. CONCLUSIONS In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.

BACKGROUND: In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters. METHODS: This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results. RESULTS: The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease. CONCLUSIONS In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.

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.

BACKGROUND/AIMS: In addition to the globally endorsed Barcelona Clinic Liver Cancer (BCLC) staging system, other algorithms or staging systems have been developed, including the Hong Kong Liver Cancer (HKLC) staging system. This study aimed to validate the HKLC staging system relative to the BCLC staging system for predicting survival for hepatocellular carcinoma (HCC) patients in Korea. METHODS: From 2004 to 2013, 2,571 patients newly diagnosed with HCC were consecutively enrolled at three Korea University medical centers. RESULTS: Both staging systems differentiated survival well (p < 0.001). However, 1-year and 3-year survival were predicted better using the HKLC system than the BCLC system (area under the receiver operating characteristic curve: 0.869 vs 0.856 for 1 year, p=0.002; 0.841 vs 0.827 for 3 years, p=0.010). In hypothetical survival curves, the HKLC system exhibited better median overall survival than the BCLC system (33.1 months vs 19.2 months). In evaluations of prognosis according to either BCLC or HKLC treatment guidelines, risk of death was reduced in the group following only HKLC guidelines compared with the group following only BCLC guidelines (hazard ratio, 0.601; 95% confidence interval, 0.443 to 0.816; p=0.001). CONCLUSIONS: Although both staging systems predicted and discriminated HCC prognoses well, the HKLC system showed more encouraging survival benefits than the BCLC system.
Academic Medical Centers ; Carcinoma, Hepatocellular ; Hong Kong ; Humans ; Korea ; Liver Neoplasms ; Liver ; Neoplasm Staging ; Prognosis ; ROC Curve