Byung-Jun Cho

Background and Objectives: Dental scaling may be associated with mental health, but whether this reflects dental care itself or broader healthcare engagement is unclear. We examined the association between dental scaling within the previous year and depressive symptoms among Korean adults and its attenuation after sequential adjustment. Materials and Methods: We analyzed 231,410 adults aged ≥ 19 years from the 2024 Korea Community Health Survey. Scaling was self-reported; depressive symptoms were defined as a Patient Health Questionnaire-9 score ≥ 10. Survey-weighted logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs). Model 2 was the primary confounder-adjusted model, whereas Model 3 (exploratory attenuation model) was additionally adjusted for oral health, healthcare access, and general health. Sensitivity analyses included an alternative PHQ-9 threshold, expanded covariate models, multiple imputation, E-values, and restricted cubic splines. Results: Depressive symptoms were less prevalent among participants reporting scaling than those not reporting scaling (3.2% vs. 5.3%). The crude OR was 0.58 (95% CI: 0.55–0.61); the Model 2 OR was 0.74 (95% CI: 0.70–0.78) and was attenuated to 0.88 (95% CI: 0.83–0.93) in Model 3. Expanded models and multiple imputation yielded similar estimates. The Model 3 E-value was 1.54 (confidence-limit E-value: 1.36). With flexible modeling of age and sleep duration, the Model 3 OR was 0.93 (95% CI: 0.87–0.98). Conclusions: Self-reported scaling within the previous year was inversely associated with PHQ-9-defined depressive symptoms, with attenuation after additional adjustment and flexible modeling. The cross-sectional design precludes causal inference, and these findings do not establish that scaling prevents or treats depressive disorders.

Background and Objectives: This study investigated the association between periodontal procedure intensity, serving as an indirect proxy for periodontal disease burden, and incident tinnitus in Korean adults. Materials and Methods: Using the Korean National Health Insurance Service–National Health Screening Cohort (2002–2019), we included adults aged ≥40 years who had a diagnosis of periodontal disease (International Classification of Diseases, 10th Revision [ICD-10] code K05), had undergone relevant periodontal treatment, and had available health-screening data. Because direct clinical periodontal measures were unavailable, participants were classified according to treatment intensity into: a mild procedure group (scaling or root planing only) and a moderate-to-severe procedure group (subgingival curettage, extraction, periodontal flap surgery, bone grafting, or guided tissue regeneration). Incident tinnitus was defined as an ICD-10 H93.1 diagnosis recorded during two or more outpatient visits to a neurology or otolaryngology department to improve diagnostic specificity. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models adjusted for demographic, socioeconomic, cardiometabolic, and behavioral factors. Results: Among 132,808 participants (76,844 mild; 55,964 moderate-to-severe), the incidence rate of tinnitus was higher in the moderate-to-severe group than in the mild group (4.38 vs. 3.87 per 1000 person-years). After adjustment, the moderate-to-severe group showed a significantly higher risk of tinnitus (HR 1.24, 95% CI 1.17–1.30). These associations were consistent across sex- and age-stratified analyses and in sensitivity analyses using stricter tinnitus definitions. Conclusions: Greater periodontal procedure intensity was associated with a modestly higher incidence of tinnitus in this nationwide cohort. Because procedure intensity serves only as an indirect surrogate for periodontal disease burden, and because auditory confounders and short-term procedure-related factors were unavailable, causality and a specific inflammatory mechanism cannot be established. Further studies incorporating direct periodontal measurements, audiological data, and prespecified lag-time analyses are warranted to confirm these findings.

Volatile organic compounds (VOCs) are common indoor air pollutants known to pose significant health risks, yet little is known about how internal exposure varies across populations and environments. This study investigated the associations between indoor air pollutants and urinary VOC biomarkers in a nationally representative sample. We analyzed data from 1880 adults in the eighth Korea National Health and Nutrition Examination Survey (2020–2021) who completed an indoor air quality (IAQ) survey and provided urine samples, assessing the influence of sociodemographic, behavioral, and environmental factors. Indoor concentrations of PM_2.5, CO₂, formaldehyde, total VOCs, benzene, ethylbenzene, toluene, xylene, and styrene were measured, alongside the urinary concentrations of nine VOC biomarkers. Associations between pollutants, sociodemographic variables, and biomarkers were evaluated using univariate and multivariable linear regression with Bonferroni correction. Older age, female, lower socioeconomic status (SES), and smoking were associated with higher urinary VOC biomarker concentrations, with smoking showing the strongest associations. Indoor ethylbenzene, styrene, benzene, and CO₂ were also associated with multiple metabolites. These findings indicated significant associations between household air pollutants and urinary VOC metabolites, with disparities by age, sex, SES, and smoking status, underscoring the importance of targeted IAQ interventions for vulnerable populations.

Severe patients visited regional emergency centers more frequently during the COVID-19 period, and disposition status warranting admission to the intensive care unit or resulting in death was more common during the COVID-19 period. This study was conducted to compare the characteristics and severity of patients, and emergency department length of stay before and after the COVID-19 outbreak. Subjects were 75,409 patients who visited the regional emergency medical center from 1 February 2019 to 19 January 2020 and from 1 February 2020 to 19 January 2021. Data was analyzed using the SPSS/WIN 22.0 program. The significance level was p < 0.05. The chi-square test and t-test were used for variables, and Cramer V was used for correlation. We found that the total number of patients visiting the emergency room decreased by 37.6% after COVID-19, but emergency department length of stay among severely ill patients increased by 203.7%. Additionally, the utilization rate of 119 ambulances and relatively more severe patients increased by 9.0% and by 2.1%. More studies about emergency department designs and operational programs should be conducted for better action not only during regular periods but also during periods of pandemic.

Despite of the changes of out-of-hospital cardiac arrest (OHCA) survival rise when bystander CPR is provided, this was only conducted in about 23% of OHCA patients in Korea in 2018. Police officers acting as first responders have a high chance of witnessing situations requiring CPR. We investigated long-term effects on CPR quality between chest compression-only CPR training and conventional CPR training in police officers to find an efficient CPR training method in a prospective, randomized, controlled trial. Police officers underwent randomization and received different CPR training. With the Brayden Pro application, we compared the accuracy of CPR skills immediately after training and the one after 3 months. Right after training, the conventional CPR group presented the accuracy of the CPR skills (compression rate: 74.6%, compression depth: 66.0%, recoil: 78.0%, compression position: 96.1%) and chest compression-only CPR group presented the accuracy of the CPR skills (compression rate: 74.5%, compression depth: 71.6%, recoil: 79.2%, compression position: 99.0%). Overall, both groups showed the good quality of CPR skills and had no meaningful difference right after the training. However, three months after training, overall accuracy of CPR skills decreased, a significant difference between two groups was observed for compression position (conventional CPR: 80.0%, chest compression only CPR: 95.0%). In multiple linear regression analysis, three months after CPR training, chest compression-only CPR training made CPR skills accuracy 28.5% higher. In conclusion, police officers showed good-quality CPR right after CPR training in both groups. But three months later, chest compression-only CPR training group had better retention of CPR skills. Therefore, chest compression-only CPR training is better to be a standard training method for police officers as first responders.

Peltophorum pterocarpum is regarded as one of the most important medicinal plants in the traditional medicine system of Vietnam. However, scientific evidence for the antioxidant effects against lipid peroxidation and the potential effects in cancer of this plant are lacking. In our experiments, 70% ethanolic extracts of P. pterocarpum leaves (LPP) and stem bark (SPP) were evaluated for their low-density lipoprotein (LDL) oxidation and cytotoxic activity against cancer cell lines. Both LPP and SPP inhibited Cu²⁺-mediated LDL by increasing the lag time of conjugated diene formation and inhibiting the generation of thiobarbituric acid reactive substances (TBARS) in a dose-dependent manner. In cancer cells, LPP and SPP triggered the most potent cytotoxic effects against human leukemia cells, CRF-SBA and HL-60, with half-maximal inhibitory concentration (IC₅₀) values ranging from 118.5 to 157.2 µg/mL. SPP exhibited significant cytotoxicity against MIA PACA2, A549, and KG cell lines with IC₅₀ values of 167.5, 244.1 and 255.0 µg/mL, respectively. Meanwhile, LPP showed cytotoxic activity against KG with an IC₅₀ value of 228.1 µg/mL. SPP mediated cytotoxicity in HL-60 and CCRF-SBA cells through the activation of the apoptosis pathway, including the activation of caspases 3, and 9 and poly (ADP-ribose) polymerase (PARP). These results suggested that SPP may prevent the development and progression of atherosclerosis and leukemia in humans.

BACKGROUND:Osteoprotegerin (OPG) is a soluble glycoprotein that belongs to the tumor necrosis factor (TNF) receptor superfamily. OPG is mainly secreted by bone. The relationship between acute resistance training, serum OPG levels and metabolic syndro...

[Purpose] This study applied active rehabilitation therapy to muscular back strength and assessed the subjective pain degree in chronic low back pain patients. [Subjects and Methods] Subjects were randomly assigned to two groups: experimental (n=8) and control (n=8). The experimental group performed two types of rehabilitation therapy programs four times per week for eight weeks. The rehabilitation program was based on the Korea Occupational Safety and Health Agency's program. There were several types of stretching and strengthening. Back strength was measured using the Back Muscle Dynamometer TKK-5402. The visual analog scale score, selected to measure degrees of subjective pain, was used to assess treatment efficacy. [Results] For the experimental group, muscular back strength increased from 133.90 ± 11.84 kg before exercise to 145.59 ± 14.49 kg after exercise. In the control group, muscular back strength decreased from 133.92 ± 3.84 kg before exercise to 133.90 ± 5.81 kg after exercise. In the experimental group, the visual analog scale score for subjective pain decreased from 6.63 ± 0.52 before exercise to 5.75 ± 0.46 after exercise; in the control group, it decreased from 5.61 ± 0.52 before exercise to 5.61 ± 0.52 after exercise. [Conclusion] Active rehabilitation therapy is a positive intervention that can provide relief from back pain.