Purpose: Declines in masticatory function have been reported to be closely associated with cognitive impairment and reduced brain activity in older adults. This study aimed to investigate the effects of intraoral vibratory stimulation on masticatory function, cognitive performance, and brain activity in elderly individuals and to evaluate its potential efficacy. Materials and Methods: Participants were divided into a vibration-stimulation group (n=9) and a non-vibration control group (n=7). Baseline assessments were conducted at the first visit. Participants then received either vibratory stimulation or a wash-out (control) condition for two weeks, followed by the same assessments at the final visit. Evaluation measures were dental assessments (maximum bite force, masticatory performance, and salivary flow rate), cognitive tests (CANTAB, paper-based and computerized tests), quantitative electroencephalography (qEEG), and functional magnetic resonance imaging (fMRI) during a short-term memory task. Results: No significant long-term effects or statistically meaningful differences were observed between the two groups in cognitive performance or brain activity. Similarly, no pre- to post-intervention differences were found between groups in dental measures related to masticatory function (maximum bite force, masticatory performance, and salivary flow rate). Due to the limited sample size, this study functioned as a pilot study focusing on descriptive rather than inferential statistical analysis. Conclusion Intraoral vibratory stimulation did not demonstrate immediate or clear effects on cognitive function or brain activity in older adults, suggesting the need for optimization of stimulation parameters such as location and intensity. Future studies with larger sample sizes and improved stimulation methods replicating masticatory function are warranted to further explore the potential cognitive benefits.

Background: and Purpose The National Brain Biobank of Korea (NBBK) is a brain bank consortium supported by the Korea Disease Control and Prevention Agency and the Korea National Institute of Health, and was launched in 2015 to support research into neurodegenerative disease dementia (NDD). This study aimed to introduce the NBBK and describes clinicopathological correlations based on analyses of data collected from the NBBK. Methods: Four hospital-based brain banks have been established in South Korea: Samsung Medical Center Brain Bank (SMCBB), Seoul National University Hospital Brain Bank (SNUHBB), Pusan National University Hospital Brain Bank (PNUHBB), and Myongji Hospital Brain Bank (MJHBB). Clinical and pathological data were collected from these brain banks using standardized protocols. The prevalence rates of clinical and pathological diagnoses were analyzed in order to characterize the clinicopathological correlations. Results: Between August 2016 and December 2023, 185 brain specimens were collected and pathologically evaluated (SNUHBB: 117; PNUHBB: 27; SMCBB: 34; MJHBB: 7). The age at consent was 70.8±12.6 years, and the age at autopsy was 71.7±12.4 years. The four-most-common clinical diagnoses were Alzheimer’s disease (AD) dementia (20.0%), idiopathic Parkinson’s disease (15.1%), unspecified dementia (11.9%), and cognitively unimpaired (CU) (11.4%).Most cases of unspecified dementia had a pathological diagnosis of central nervous system (CNS) vasculopathy (31.8%) or AD (31.8%). Remarkably, only 14.2% of CU cases had normal pathological findings. The three-most-common pathological diagnoses were AD (26.5%), CNS vasculopathy (14.1%), and Lewy body disease (13.5%). Conclusions These clinical and neuropathological findings provide a deeper understanding of the mechanisms underlying NDD in South Korea.

Background: and Purpose The National Brain Biobank of Korea (NBBK) is a brain bank consortium supported by the Korea Disease Control and Prevention Agency and the Korea National Institute of Health, and was launched in 2015 to support research into neurodegenerative disease dementia (NDD). This study aimed to introduce the NBBK and describes clinicopathological correlations based on analyses of data collected from the NBBK. Methods: Four hospital-based brain banks have been established in South Korea: Samsung Medical Center Brain Bank (SMCBB), Seoul National University Hospital Brain Bank (SNUHBB), Pusan National University Hospital Brain Bank (PNUHBB), and Myongji Hospital Brain Bank (MJHBB). Clinical and pathological data were collected from these brain banks using standardized protocols. The prevalence rates of clinical and pathological diagnoses were analyzed in order to characterize the clinicopathological correlations. Results: Between August 2016 and December 2023, 185 brain specimens were collected and pathologically evaluated (SNUHBB: 117; PNUHBB: 27; SMCBB: 34; MJHBB: 7). The age at consent was 70.8±12.6 years, and the age at autopsy was 71.7±12.4 years. The four-most-common clinical diagnoses were Alzheimer’s disease (AD) dementia (20.0%), idiopathic Parkinson’s disease (15.1%), unspecified dementia (11.9%), and cognitively unimpaired (CU) (11.4%).Most cases of unspecified dementia had a pathological diagnosis of central nervous system (CNS) vasculopathy (31.8%) or AD (31.8%). Remarkably, only 14.2% of CU cases had normal pathological findings. The three-most-common pathological diagnoses were AD (26.5%), CNS vasculopathy (14.1%), and Lewy body disease (13.5%). Conclusions These clinical and neuropathological findings provide a deeper understanding of the mechanisms underlying NDD in South Korea.

Background: South Korean on-site workers in the public sector, fully covered by the Occupational Safety and Health Act, often perform hazardous tasks. However, their status and injury rates remain poorly documented. This study aimed to analyze changes in injury rates and the proportion of work-related diseases (WRDs) among on-site workers in basic local governments (BLGs) following workforce reductions between 2016 and 2018. Methods: Data from two sources provided by the Ministry of Employment and Labor were analyzed: organizational data on the number of on-site workers, and cases of injuries, deaths, and diseases among on-site workers in 226 BLGs from 2016 to 2018; and workers’ compensation claims data (individual data) for on-site workers in BLGs during the same period. Injury, mortality, and disease incidence rates were calculated and compared between BLGs with increased and decreased workforce. The proportion of WRDs among all the injuries was also examined. Results: The total number of on-site workers in BLGs decreased by 18.1% in 2018 compared with 2016. The injury rate increased from 0.46% in 2016 to 0.62% in 2018. BLGs with workforce reductions showed higher injury rates, particularly in those with fewer than 1,000 on-site workers. The proportion of WRDs among all injuries increased by 1.34 times in 2018 compared with 2016. Conclusions Workforce reductions among on-site workers in BLGs are associated with higher injury rates and a great proportion of WRDs. These findings highlight the need for improved occupational safety and health practices within the public sector and serve as an important basis for establishing workforce management and injury prevention policies. However, limitations in the available data made it challenging to identify worker groups particularly vulnerable to WRDs. Further research is needed, as it is critical for the development of effective occupational safety and health policies.

Background: and Purpose The National Brain Biobank of Korea (NBBK) is a brain bank consortium supported by the Korea Disease Control and Prevention Agency and the Korea National Institute of Health, and was launched in 2015 to support research into neurodegenerative disease dementia (NDD). This study aimed to introduce the NBBK and describes clinicopathological correlations based on analyses of data collected from the NBBK. Methods: Four hospital-based brain banks have been established in South Korea: Samsung Medical Center Brain Bank (SMCBB), Seoul National University Hospital Brain Bank (SNUHBB), Pusan National University Hospital Brain Bank (PNUHBB), and Myongji Hospital Brain Bank (MJHBB). Clinical and pathological data were collected from these brain banks using standardized protocols. The prevalence rates of clinical and pathological diagnoses were analyzed in order to characterize the clinicopathological correlations. Results: Between August 2016 and December 2023, 185 brain specimens were collected and pathologically evaluated (SNUHBB: 117; PNUHBB: 27; SMCBB: 34; MJHBB: 7). The age at consent was 70.8±12.6 years, and the age at autopsy was 71.7±12.4 years. The four-most-common clinical diagnoses were Alzheimer’s disease (AD) dementia (20.0%), idiopathic Parkinson’s disease (15.1%), unspecified dementia (11.9%), and cognitively unimpaired (CU) (11.4%).Most cases of unspecified dementia had a pathological diagnosis of central nervous system (CNS) vasculopathy (31.8%) or AD (31.8%). Remarkably, only 14.2% of CU cases had normal pathological findings. The three-most-common pathological diagnoses were AD (26.5%), CNS vasculopathy (14.1%), and Lewy body disease (13.5%). Conclusions These clinical and neuropathological findings provide a deeper understanding of the mechanisms underlying NDD in South Korea.

Background: s/Aims: Liver stiffness measurement (LSM) using vibration-controlled transient elastography (VCTE) can assess fibrotic burden in chronic liver diseases. The systematic review and meta-analysis was conducted to determine whether LSM using VCTE can predict the risk of development of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. Methods: A systematic literature search of the Ovid-Medline, EMBASE, Cochrane, and KoreaMed databases (from January 2010 to June 2023) was conducted. Of the 1,345 individual studies identified, 10 studies that used VCTE were finally registered. Hazard ratios (HRs) and the 95% confidence intervals (CIs) were considered summary estimates of treatment effect sizes of ≥11 kilopascal (kPa) standard for HCC development. Meta-analysis was performed using the restricted Maximum Likelihood random effects model. Results: Among the ten studies, data for risk ratios for HCC development could be obtained from nine studies. When analyzed for the nine studies, the HR for HCC development was high at 3.33 (95% CI, 2.45–4.54) in CHB patients with a baseline LSM of ≥11 kPa compared to patients who did not. In ten studies included, LSM of ≥11 kPa showed the sensitivity and specificity for predicting HCC development were 61% (95% CI, 50–71%) and 78% (95% CI, 66–86%), respectively, and the diagnostic accuracy was 0.74 (95% CI, 0.70–0.77). Conclusions The risk of HCC development was elevated in CHB patients with VCTE-determined LSM of ≥11 kPa. This finding suggests that VCTE-determined LSM values may aid the risk prediction of HCC development in CHB patients.

Background: s/Aims: This meta-analysis examined whether preoperative vibration-controlled transient elastography (VCTE) can predict postoperative complications and recurrence in patients undergoing hepatic resection for hepatocellular carcinoma (HCC). Methods: A systematic literature search was conducted using Ovid-Medline, EMBASE, Cochrane, and KoreaMed databases. Out of 431 individual studies, thirteen published between 2008 and 2022 were included. Five studies focused on HCC recurrence, while eight examined postoperative complications. Results: The meta-analysis of five studies on HCC recurrence showed that the high-risk group with a high VCTE score had a significantly increased recurrence rate after hepatic resection (hazard ratio 2.14). The cutoff value of VCTE in the high-risk group of HCC recurrence was 7.4–13.4 kPa, the sensitivity was 0.60 (95% confidence interval [CI] 0.47–0.72), and the specificity was 0.60 (95% CI 0.46–0.72). The area under the receiver operating characteristic curve (AUC) of the liver stiffness measured by VCTE to predict the HCC recurrence was 0.63 (95% CI 0.59–0.67). The meta-analysis on the postoperative complications revealed a significantly increased risk of postoperative complications in the high-risk group (12–25.6 kPa) with a high VCTE value (odds ratio [OR], 8.32). The AUC of the liver stiffness measured by VCTE to predict the postoperative complications was 0.87 (95% CI 0.84–0.90), the sensitivity was 0.76 (95% CI 0.55–0.89) and the specificity was 0.85 (95% CI 0.73–0.92). Conclusions This meta-analysis suggests that preoperative VCTE in patients undergoing hepatic resection for HCC is useful in identifying individuals at a high risk of postoperative complications and HCC recurrence.

Objective: To validate a simplified ordinal scoring method, referred to as modified length-based grading, for assessing coronary artery calcium (CAC) severity on non-electrocardiogram (ECG)-gated chest computed tomography (CT). Materials and Methods: This retrospective study enrolled 120 patients (mean age ± standard deviation [SD], 63.1 ± 14.5 years; male, 64) who underwent both non-ECG-gated chest CT and ECG-gated cardiac CT between January 2011 and December 2021. Six radiologists independently assessed CAC severity on chest CT using two scoring methods (visual assessment and modified length-based grading) and categorized the results as none, mild, moderate, or severe. The CAC category on cardiac CT assessed using the Agatston score was used as the reference standard. Agreement among the six observers for CAC category classification was assessed using Fleiss kappa statistics. Agreement between CAC categories on chest CT obtained using either method and the Agatston score categories on cardiac CT was assessed using Cohen’s kappa. The time taken to evaluate CAC grading was compared between the observers and two grading methods. Results: For differentiation of the four CAC categories, interobserver agreement was moderate for visual assessment (Fleiss kappa, 0.553 [95% confidence interval {CI}: 0.496–0.610]) and good for modified length-based grading (Fleiss kappa, 0.695 [95% CI: 0.636–0.754]). The modified length-based grading demonstrated better agreement with the reference standard categorization with cardiac CT than visual assessment (Cohen’s kappa, 0.565 [95% CI: 0.511–0.619 for visual assessment vs. 0.695 [95% CI: 0.638–0.752] for modified length-based grading). The overall time for evaluating CAC grading was slightly shorter in visual assessment (mean ± SD, 41.8 ± 38.9 s) than in modified length-based grading (43.5 ± 33.2 s) (P < 0.001). Conclusion The modified length-based grading worked well for evaluating CAC on non-ECG-gated chest CT with better interobserver agreement and agreement with cardiac CT than visual assessment.