Background: Three automobile company workers (one from Factory D and two from Factory E) were diagnosed with amyotrophic lateral sclerosis. The Korean Epidemiologic Investigation and Evaluation Committee determined that there is considerable scientific evidence supporting the association between amyotrophic lateral sclerosis and combined exposure to heavy metals, organic solvents, and diesel exhaust at the manufacturing plant. Case presentation: Patient A, who primarily engaged in engine processing and completed vehicle inspection at Factory D, was exposed to considerable amounts of heavy metals and organic solvents during medium- and large-engine processing, welding, and painting for over 23 years. Additionally, the patient was likely exposed to diesel exhaust for 33 years from forklifts delivering engines in the workshop. Patients B and C, who were responsible for engine assembly, ignition testing, and engine shipment at Factory E since around 1990, were exposed to lead and benzene from gasoline during engine ignition tests in the engine department for 15 and 16 years, respectively. They also encountered welding fumes, heavy metals, and organic solvents during welding and painting tasks. In addition, Patients B and C were continuously exposed to diesel exhaust from logistics vehicles on standby during work hours for 25 and 30 years, respectively. Conclusions Although the specific level of lead exposure causing amyotrophic lateral sclerosis remains undetermined, numerous studies have consistently reported a relationship between lead exposure and disease development. Limited evidence suggests that exposure to organic solvents and diesel exhaust may increase the risk of amyotrophic lateral sclerosis. Therefore, the Epidemiological Investigation and Evaluation Committee concluded that the three patients’ work-related exposure to heavy metals, organic solvents, and diesel exhaust is significantly supported by scientific evidence as a cause of their amyotrophic lateral sclerosis.

Background: Three automobile company workers (one from Factory D and two from Factory E) were diagnosed with amyotrophic lateral sclerosis. The Korean Epidemiologic Investigation and Evaluation Committee determined that there is considerable scientific evidence supporting the association between amyotrophic lateral sclerosis and combined exposure to heavy metals, organic solvents, and diesel exhaust at the manufacturing plant. Case presentation: Patient A, who primarily engaged in engine processing and completed vehicle inspection at Factory D, was exposed to considerable amounts of heavy metals and organic solvents during medium- and large-engine processing, welding, and painting for over 23 years. Additionally, the patient was likely exposed to diesel exhaust for 33 years from forklifts delivering engines in the workshop. Patients B and C, who were responsible for engine assembly, ignition testing, and engine shipment at Factory E since around 1990, were exposed to lead and benzene from gasoline during engine ignition tests in the engine department for 15 and 16 years, respectively. They also encountered welding fumes, heavy metals, and organic solvents during welding and painting tasks. In addition, Patients B and C were continuously exposed to diesel exhaust from logistics vehicles on standby during work hours for 25 and 30 years, respectively. Conclusions Although the specific level of lead exposure causing amyotrophic lateral sclerosis remains undetermined, numerous studies have consistently reported a relationship between lead exposure and disease development. Limited evidence suggests that exposure to organic solvents and diesel exhaust may increase the risk of amyotrophic lateral sclerosis. Therefore, the Epidemiological Investigation and Evaluation Committee concluded that the three patients’ work-related exposure to heavy metals, organic solvents, and diesel exhaust is significantly supported by scientific evidence as a cause of their amyotrophic lateral sclerosis.

Background: Three automobile company workers (one from Factory D and two from Factory E) were diagnosed with amyotrophic lateral sclerosis. The Korean Epidemiologic Investigation and Evaluation Committee determined that there is considerable scientific evidence supporting the association between amyotrophic lateral sclerosis and combined exposure to heavy metals, organic solvents, and diesel exhaust at the manufacturing plant. Case presentation: Patient A, who primarily engaged in engine processing and completed vehicle inspection at Factory D, was exposed to considerable amounts of heavy metals and organic solvents during medium- and large-engine processing, welding, and painting for over 23 years. Additionally, the patient was likely exposed to diesel exhaust for 33 years from forklifts delivering engines in the workshop. Patients B and C, who were responsible for engine assembly, ignition testing, and engine shipment at Factory E since around 1990, were exposed to lead and benzene from gasoline during engine ignition tests in the engine department for 15 and 16 years, respectively. They also encountered welding fumes, heavy metals, and organic solvents during welding and painting tasks. In addition, Patients B and C were continuously exposed to diesel exhaust from logistics vehicles on standby during work hours for 25 and 30 years, respectively. Conclusions Although the specific level of lead exposure causing amyotrophic lateral sclerosis remains undetermined, numerous studies have consistently reported a relationship between lead exposure and disease development. Limited evidence suggests that exposure to organic solvents and diesel exhaust may increase the risk of amyotrophic lateral sclerosis. Therefore, the Epidemiological Investigation and Evaluation Committee concluded that the three patients’ work-related exposure to heavy metals, organic solvents, and diesel exhaust is significantly supported by scientific evidence as a cause of their amyotrophic lateral sclerosis.

A resorbable barrier membrane is commonly used for the repair of perforated sinus membranes during sinus lifting surgeries. However, repairing largescale perforations poses challenges for clinicians as the protection and isolation of graft material remain uncertain. With this technique, we aimed to prevent graft material loss and subsequent sinus-related complications using intra-sinus rigid fixation of the resorbable barrier membrane in cases with a large perforation of the sinus membrane.

Purpose: Intramedullary nailing is used widely for treating tibial diaphysis fractures because of its relatively rigid internal fixation, which allows weight bearing, resulting in rapid bone healing and functional recovery. This study evaluated the results of exchange nailing in treating aseptic nonunion of tibial shaft fractures. Materials and Methods: From November 2015 to December 2021, a retrospective study was conducted on patients who had undergone intramedullary nailing for tibial diaphysis fractures. Among them, this study focused on patients diagnosed with nonunion and who underwent exchange nailing. Twenty patients with a minimum follow-up period of at least 12 months were included in the study. Results: The mean ages of patients were 60 years (range, 30-79 years). Of the 20 cases in which exchange nailing was performed, bone union was achieved in 18 cases (90.0%), and the mean period was 23 weeks (range, 14-46 weeks). Among the 18 cases of bone union, one case exhibited delayed union and achieved union without additional treatment after 46 weeks, while two cases of nonunion failed to achieve union and were lost to follow-up until the final assessment. Conclusion Reamed exchange nailing performed on aseptic nonunion after intramedullary nailing for tibial diaphysis fractures had satisfactory clinical outcomes.

Microplastics are environmental pollutants that prevail in the oceans, remote islands, and polar regions. Exposure to microplastics presents a major emerging threat to the ecosystems due to their potential adverse effects. Herein, we reviewed the literature to provide an up-to-date synopsis of the current understanding of the sources, compositions, and adverse effects of microplastics in humans and the environment. Most studies on microplastics have focused on developing standardized methods for monitoring the occurrence, distribution, and movement of microplastics in the environment, as well as developing microplastic substitutes; however, although humans are exposed to microplastics via various routes, research on the adverse effects of microplastics in humans remains limited. Little is known about the impact of microplastics on human health and the toxic effects that may vary depending on the type, size, shape, and concentration of microplastics. Therefore, more research is needed to understand the cellular and molecular mechanisms of microplastic toxicity and related pathologies.

Background: s/Aims: This study was performed to reveal the usefulness of the trabecular bone score (TBS) in assessing bone strength in patients with ankylosing spondylitis (AS) in comparison with dual-energy X-ray absorptiometry (DXA) methods. Methods: A total of 215 AS patients (75.8% male) were enrolled from a single university hospital in Korea. Demographic and clinical information were assessed. Patients completed X-rays of the cervical and lumbar spine (L-spine), and spinal ankyloses were quantified using the modified Stoke AS Spine Score (mSASSS). Hip, anteroposterior and lateral L-spine bone mineral density (BMD) and TBS were assessed by DXA methods. Clinical characteristics and bone strength measurement results were compared between male and female AS patients. The accuracy of each bone strength evaluation method in predicting Fracture Risk Assessment Tool (FRAX) scores indicating moderate or higher fracture risk was compared by receiver operating characteristic curves in patients aged ≥ 40 years. Correlations between each bone strength measurement method and mSASSS were examined. Results: Male patients showed higher mSASSS and less prevalent peripheral joint involvement compared to female patients (p < 0.05). TBS, hip BMD, and L-spine lateral BMD showed comparably high areas under the curve (AUCs) for predicting FRAX-major osteoporotic fractures (MOF) ≥ 10% (AUC ranged 0.72 to 0.76). TBS negatively correlated with mSASSS in both male and female patients (p < 0.01). Conclusions TBS could predict the risk of MOF and is not influenced by spinal osteoproliferation in AS patients, even in those with advanced spinal changes.

Background: s: Recently, alternative surrogate endpoints such as a 30% or 40% decline in estimated glomerular filtration rate (eGFR) or eGFR slope over 2 to 3 years have been proposed for predicting renal outcomes. However, the impact of GFR estimation methods on the accuracy and effectiveness of surrogate markers is unknown. Methods: We retrospectively enrolled participants in health screening programs at three hospitals from 1995 to 2009. We defined two different participant groups as YR1 and YR3, which had available 1-year or 3-year eGFR values along with their baseline eGFR levels. We compared the effectiveness of eGFR percentage change or slope to estimate end-stage renal disease (ESRD) risk according to two estimating equations (modified Modification of Diet in Renal Disease equation [eGFRm] and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation [eGFRc]) for GFR. Results: In the YR1 and YR3 groups, 9,971 and 10,171 candidates were enrolled and ESRD incidence during follow-up was 0.26% and 0.19%, respectively. The eGFR percentage change was more effective than eGFR slope in estimating ESRD risk, regardless of the method of estimation. A 40% of decline in eGFR was better than 30%, and a 3-year baseline period was better than a 1-year period for prediction accuracy. Although some diagnostic indices from the CKD-EPI equation were better, we found no significant differences in the discriminative ability and hazard ratios for incident ESRD between eGFRc and eGFRm in either eGFR percentage change or eGFR slope. Conclusion There were no significant differences in the prediction accuracy of GFR percentage change or eGFR slope between eGFRc and eGFRm in the general population.

Background: s: Recently, alternative surrogate endpoints such as a 30% or 40% decline in estimated glomerular filtration rate (eGFR) or eGFR slope over 2 to 3 years have been proposed for predicting renal outcomes. However, the impact of GFR estimation methods on the accuracy and effectiveness of surrogate markers is unknown. Methods: We retrospectively enrolled participants in health screening programs at three hospitals from 1995 to 2009. We defined two different participant groups as YR1 and YR3, which had available 1-year or 3-year eGFR values along with their baseline eGFR levels. We compared the effectiveness of eGFR percentage change or slope to estimate end-stage renal disease (ESRD) risk according to two estimating equations (modified Modification of Diet in Renal Disease equation [eGFRm] and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation [eGFRc]) for GFR. Results: In the YR1 and YR3 groups, 9,971 and 10,171 candidates were enrolled and ESRD incidence during follow-up was 0.26% and 0.19%, respectively. The eGFR percentage change was more effective than eGFR slope in estimating ESRD risk, regardless of the method of estimation. A 40% of decline in eGFR was better than 30%, and a 3-year baseline period was better than a 1-year period for prediction accuracy. Although some diagnostic indices from the CKD-EPI equation were better, we found no significant differences in the discriminative ability and hazard ratios for incident ESRD between eGFRc and eGFRm in either eGFR percentage change or eGFR slope. Conclusion There were no significant differences in the prediction accuracy of GFR percentage change or eGFR slope between eGFRc and eGFRm in the general population.

Background: s/Aims: This study was performed to reveal the usefulness of the trabecular bone score (TBS) in assessing bone strength in patients with ankylosing spondylitis (AS) in comparison with dual-energy X-ray absorptiometry (DXA) methods. Methods: A total of 215 AS patients (75.8% male) were enrolled from a single university hospital in Korea. Demographic and clinical information were assessed. Patients completed X-rays of the cervical and lumbar spine (L-spine), and spinal ankyloses were quantified using the modified Stoke AS Spine Score (mSASSS). Hip, anteroposterior and lateral L-spine bone mineral density (BMD) and TBS were assessed by DXA methods. Clinical characteristics and bone strength measurement results were compared between male and female AS patients. The accuracy of each bone strength evaluation method in predicting Fracture Risk Assessment Tool (FRAX) scores indicating moderate or higher fracture risk was compared by receiver operating characteristic curves in patients aged ≥ 40 years. Correlations between each bone strength measurement method and mSASSS were examined. Results: Male patients showed higher mSASSS and less prevalent peripheral joint involvement compared to female patients (p < 0.05). TBS, hip BMD, and L-spine lateral BMD showed comparably high areas under the curve (AUCs) for predicting FRAX-major osteoporotic fractures (MOF) ≥ 10% (AUC ranged 0.72 to 0.76). TBS negatively correlated with mSASSS in both male and female patients (p < 0.01). Conclusions TBS could predict the risk of MOF and is not influenced by spinal osteoproliferation in AS patients, even in those with advanced spinal changes.