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This study evaluates the utility of OpenCap (v0.3), a smartphone-based motion capture system, for performing gait analysis in patients with neurological disorders. We compared kinematic and kinetic gait parameters between 10 healthy controls and 10 patients with neurological conditions, including stroke, Parkinson's disease, and cerebral palsy. OpenCap captured 3D movement dynamics using two smartphones, with data processed through musculoskeletal modeling. The key findings indicate that the patient group exhibited significantly slower gait speeds (0.67 m/s vs. 1.10 m/s, p = 0.002), shorter stride lengths (0.81 m vs. 1.29 m, p = 0.001), and greater step length asymmetry (107.43% vs. 91.23%, p = 0.023) compared to the controls. Joint kinematic analysis revealed increased variability in pelvic tilt, hip flexion, knee extension, and ankle dorsiflexion throughout the gait cycle in patients, indicating impaired motor control and compensatory strategies. These results indicate that OpenCap can effectively identify significant gait differences, which may serve as valuable biomarkers for neurological disorders, thereby enhancing its utility in clinical settings where traditional motion capture systems are impractical. OpenCap has the potential to improve access to biomechanical assessments, thereby enabling better monitoring of gait abnormalities and informing therapeutic interventions for individuals with neurological disorders.

Objective: This study aimed to investigate the long-term effects and functional outcomes of androgen suppression therapy using leuprorelin among Korean patients with spinal and bulbar muscular atrophy (SBMA)., Methods: This observational study enrolled patients with genetically confirmed SBMA who provided informed consent. Leuprorelin was administered via subcutaneous injection every 12 weeks. The primary outcome measure was the change in total Spinal and Bulbar Muscular Atrophy Functional Rating Scale (SBMAFRS) scores., Results: A total of 48 SBMA patients were evaluated in this study. Among them, 39 patients underwent androgen suppression therapy over a 3-year period. The total SBMAFRS score decreased from 41.72 ± 5.55 to 36.74 ± 7.74 (p < 0.001) in patients who completed their treatment. The subgroup with a baseline SBMAFRS score of ≥ 42 had a significantly lower decline in SBMAFRS score than did those with a baseline SBMAFRS score of ≤ 41. We determined that at a baseline, SBMAFRS cutoff value of 41.5 could predict good prognosis, with a corresponding area under the curve of 0.689., Conclusion: Despite androgen suppression therapy, all enrolled participants exhibited a decrease in the overall SBMAFRS score. However, those with a baseline SBMAFRS of ≥ 42 showed a mild decrease in scores, indicating a more favorable prognosis. These findings suggest that a higher baseline motor function was a key prognostic indicator in SBMA treatment and that initiating early leuprorelin treatment in patients with high baseline function may lead to good clinical outcomes., (© 2024. Fondazione Società Italiana di Neurologia.)

Background: Disturbance of circadian rhythms caused by shift work has adverse effects on insulin resistance. Many previous studies have confirmed that shift work and insulin resistance are related using homeostasis model assessment-insulin resistance, one of the insulin resistance indicators. However, the triglycerides and glucose index (TyG index) has recently been studied as an insulin resistance indicator. The aim of this study is to investigate the association of shift work and TyG index, one of the indirect indicators of insulin resistance, using results of health checkups in one workplace., Methods: Based on medical examination data collected in February 2019, a total of 3,794 subjects from one chemical plant in Korea were selected for this study. Cut-off value of TyG index for predicting development of diabetes mellitus (DM) was 4.69. A multiple logistic regression analysis was performed after adjusting for age, employment period, obesity, abdominal obesity, smoking, drinking, physical activity, hypertension, stroke, heart disease., Results: As a result of logistic regression analysis, compared to day workers, odds ratio (OR) with a TyG index above cut-off value for predicting development of DM in shift workers was 1.220 after adjusting for age, employment period, obesity, abdominal obesity, smoking, drinking, physical activity, hypertension, stroke, heart disease (Model 1, OR: 1.276; 95% confidence interval [CI]: 1.099-1.482; Model 2, OR: 1.232; 95% CI: 1.055-1.438; Model 3, OR: 1.220, 95% CI: 1.030-1.444)., Conclusions: There was a significant association between shift work and TyG index among male workers in a chemical plant. More research studies on the association between shift work and TyG index are needed in the future., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Korean Society of Occupational & Environmental Medicine.)

In this study, we investigated the efficacy of kaempferol (a flavonoid found in plants and plant-derived foods such as kale, beans, tea, spinach and broccoli) on vascular contractibility and aimed to clarify the detailed mechanism underlying the relaxation. Isometric contractions of divested muscles were stored and linked with western blot analysis which was carried out to estimate the phosphorylation of myosin phosphatase targeting subunit 1 (MYPT1) and phosphorylation-dependent inhibitory protein for myosin phosphatase (CPI-17) and to estimate the effect of kaempferol on the RhoA/ROCK/CPI-17 pathway. Kaempferol conspicuously impeded phorbol ester-, fluoride- and a thromboxane mimetic-derived contractions regardless of endothelial nitric oxide synthesis, indicating its direct effect on smooth muscles. It also conspicuously impeded the fluoride-derived elevation in phospho-MYPT1 rather than phospho-CPI-17 levels and phorbol 12,13-dibutyrate-derived increase in phospho-CPI-17 and phospho-ERK1/2 levels, suggesting the depression of PKC and MEK activities and subsequent phosphorylation of CPI-17 and ERK1/2. Taken together, these outcomes suggest that kaempferol-derived relaxation incorporates myosin phosphatase retrieval and calcium desensitization, which appear to be modulated by CPI-17 dephosphorylation mainly through PKC inactivation.

Background: The rise in single-person households is a global phenomenon with well-documented implications for both physical and mental well-being. However, there remains a scarcity of studies focusing specifically on the health impacts of single-person households on workers. This study aims to address this gap by comparing insomnia symptoms between single- and multi-person household workers, shedding light on the health implications of household composition., Methods: This study utilized data from the Sixth Korean Working Conditions Survey. Insomnia symptoms were categorized into normal sleep and insomnia symptom groups utilizing the 3-item Minimal Insomnia Symptom Scale. Multiple logistic regression analysis was employed to examine the association between single-person household wage workers and insomnia symptoms., Results: In comparison to wage workers from multi-person households, those from single-person households exhibited heightened risks of reporting insomnia symptoms. In the fully adjusted model, the odds ratios for symptoms of insomnia among single-person household wage workers was 1.173 (95% confidence interval: 1.020-1.349)., Conclusions: This study underscores that single-person household wage workers in Korea face an elevated risk of insomnia symptoms compared to their counterparts in multi-person households.

Objective: Providing inpatient nursing care inevitably involves night shift work. However, night shift work nurses often face psychiatric health problems such as burnout. If night shift work is an essential work type for nurses, it is necessary to select personnel suitable for night shift work or establish improvement measures such as psychiatric intervention through psychiatric evaluation. The objective of this study was to identify factors that could be interventional among factors affecting burnout in shift-working nurses., Methods: A total of 231 night shift female nurses participated in this study. A questionnaire survey was given to assess their general characteristics. To assess burnout, the Maslach Burnout Inventory-General Survey Korean version was adopted. In addition, several mental health scales were used to identify individual psychological characteristics. To identify variables associated with the presence of burnout, odds ratios were calculated using a logistic regression model taking three dimensions of burnout as a dependent variable after adjusting for psychological and occupational factors., Results: High resilience was a significant preventive factor in the three dimensions of burnout. Regarding occupational factor, the longer the duration of employment, the higher depersonalization, but the professional efficacy was good., Conclusion: Our results indicate that resilience and social support could be prevention factors for burnout. This study is meaningful in examining items that require active intervention and support for burnout targeting night shift nurses who are indispensable for patient care.

Objectives: To investigate the predictability of synthetic relaxometry for neurodevelopmental outcomes in premature infants and to evaluate whether a combination of relaxation times with clinical variables or qualitative MRI abnormalities improves the predictive performance., Methods: This retrospective study included 33 premature infants scanned with synthetic MRI near or at term equivalent age. Based on neurodevelopmental assessments at 18-24 months of corrected age, infants were classified into two groups (no/mild disability [n = 23] vs. moderate/severe disability [n = 10]). Clinical and MRI characteristics associated with moderate/severe disability were explored, and combined models incorporating independent predictors were established. Ultimately, the predictability of relaxation times, clinical variables, MRI findings, and a combination of the two were evaluated and compared. The models were internally validated using bootstrap resampling., Results: Prolonged T1-frontal/parietal and T2-parietal periventricular white matter (PVWM), moderate-to-severe white matter abnormality, and bronchopulmonary dysplasia were significantly associated with moderate/severe disability. The overall predictive performance of each T1-frontal/-parietal PVWM model was comparable to that of individual MRI finding and clinical models (AUC = 0.71 and 0.76 vs. 0.73 vs. 0.83, respectively; p > 0.27). The combination of clinical variables and T1-parietal PVWM achieved an AUC of 0.94, sensitivity of 90%, and specificity of 91.3%, outperforming the clinical model alone (p = 0.049). The combination of MRI finding and T1-frontal PVWM yielded AUC of 0.86, marginally outperforming the MRI finding model (p = 0.09). Bootstrap resampling showed that the models were valid., Conclusions: It is feasible to predict adverse outcomes in premature infants by using early synthetic relaxometry. Combining relaxation time with clinical variables or MRI finding improved prediction., Clinical Relevance Statement: Synthetic relaxometry performed during the neonatal period may serve as a biomarker for predicting adverse neurodevelopmental outcomes in premature infants., Key Points: • Synthetic relaxometry based on T1 relaxation time of parietal periventricular white matter showed acceptable performance in predicting adverse outcome with an AUC of 0.76 and an accuracy of 78.8%. • The combination of relaxation time with clinical variables and/or structural MRI abnormalities improved predictive performance of adverse outcomes. • Synthetic relaxometry performed during the neonatal period helps predict adverse neurodevelopmental outcome in premature infants., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Neuropathic pain (NP) following spinal cord injury (SCI) is refractory to pain control strategies, and the underlying neuronal mechanisms remain poorly understood. This study aimed to determine the brain regions engaged in maintaining a spontaneous resting state and the link between those regions and the severity of NP in patients with incomplete SCI. Seventy-three subjects (41 patients and 32 age- and sex-matched healthy controls) participated in this retrospective study. Regarding the neurological level of injury, patients with incomplete SCI experienced at-level or below-level NP. The severity of NP was evaluated using a visual analog scale (VAS), and patients were divided into mild and moderate-severe NP groups based on VAS scores. Graph theory and fractional amplitude of low-frequency fluctuation (fALFF) analyses were performed to compare resting-state functional magnetic resonance imaging (fMRI) analysis results among the three groups. Graph theory analysis was performed through a region of interest (ROI)-to-ROI analysis and then fALFF analysis was performed in the brain regions demonstrating significant differences among the three groups analyzed using the graph theory. We evaluated whether the brain regions showing significant differences using graph theory and fALFF correlated with the VAS scores. Patients with moderate-severe NP showed reduced node degree and fALFF in the left middle frontal gyrus compared with those with mild NP and healthy controls. Furthermore, patients with severe NP demonstrated increased average path lengths and reduced fALFF values in the posterior cingulate gyrus. This study found that changes in intrinsic oscillations of fMRI signals in the middle frontal gyrus and posterior cingulate gyrus were significant considering the severity of NP.

Background: The purpose of this study is to investigate the relationship between job stress and impaired fasting glycemia (IFG) of male workers in a manufacturing industry., Methods: Data were collected from 5,886 male workers in a manufacturing industry who participated in the medical examination from June 19 to August 14, 2020 through self-reported questionnaires. The general characteristics of the subjects, shift work, high blood pressure, dyslipidemia, and job stress were included. Job stress was measured using the Korean Occupational Stress Scale (KOSS) consisting of 8 items and 43 questions. Multivariable logistic regression analysis was used to investigate the IFG association with job stress., Results: Among the various factors that can cause job stress, only high job demand was associated with a risk of IFG (odds ratio, 1.43; 95% confidence interval, 1.13-1.82) especially in non-shift worker. For all other factors, no statistically significant results were obtained., Conclusions: In this study of male workers engaged in the Korean steel manufacturing industry, the 'job demand' item among job stress of non-shift worker was related to IFG., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2023 Korean Society of Occupational & Environmental Medicine.)

A styrene monomer (SM) oil vapor leak occurred at a chemical plant in Seosan, South Korea on 17 May 2019. A bad odor developed, and many residents complained of various symptoms and visited nearby medical institutions. We analyzed the demographic and clinical characteristics of patients treated at local hospitals and clinics for symptoms related to SM exposure, and identified factors affecting symptom persistence in any organ. Data were collected by the main Seosan office, and 1201 (33.0%) subjects agreed to participate in this study. We used the Assessment of Chemical Exposure toolkit of the Agency for Toxic Substances and Disease Registry. Logistic regression was performed to determine whether mental health symptoms prior to the accident were risk factors for symptom persistence. The strongest risk factor for persistence of at least one symptom in any organ was a preexisting mental health symptom (odds ratio [OR] = 5.47, 95% confidence interval [CI]: 2.57-11.65). Persistent symptoms of the nervous (OR = 1.54), musculoskeletal (OR = 1.92), and gastrointestinal (OR = 1.45) systems were observed. Prior mental health symptoms are risk factors for persistent physical symptoms after a chemical disaster. After a disaster, management of individuals with preaccident mental symptoms or disease is needed.

Background: Perfluoroalkyl substances (PFAS) are chemicals widely used in various products in everyday life. Due to its unique strong binding force, the half-life of PFAS is very long, so bioaccumulation and toxicity to the human body are long-standing concerns. In particular, effects on kidney function have recently emerged and there are no studies on the effect of PFAS on kidney function through epidemiological investigations in Korea. From 2018 to 2020, the Korean National Environmental Health Survey (KoNEHS) cycle 4, conducted an epidemiological investigation on the blood concentration of PFAS for the first time in Korea. Based on this data, the relationship between PFAS blood concentration and kidney function was analyzed for adolescents., Methods: We investigated 5 types of PFAS and their total blood concentration in 811 middle and high school students, living in Korea and included in KoNEHS cycle 4, and tried to find changes in kidney function in relation to PFAS concentration. After dividing the concentration of each of the 5 PFAS and the total concentration into quartiles, multivariable linear regression was performed to assess the correlation with kidney function. The bedside Schwartz equation was used as an indicator of kidney function., Results: As a result of multivariable linear regression, when observing a change in kidney function according to the increase in the concentration of each of the 5 PFAS and their total, a significant decrease in kidney function was confirmed in some or all quartiles., Conclusions: In this cross-sectional study of Korean adolescents based on KoNEHS data, a negative correlation between serum PFAS concentration and kidney function was found. A well-designed longitudinal study and continuous follow-up are necessary., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2023 Korean Society of Occupational & Environmental Medicine.)

Acute lymphocytic leukemia is one of the most common cancers in children. Multi-drug chemotherapy is used for treatment, and the representative drug is vincristine. Although various side effects may occur due to vincristine, the association with peripheral neuropathy is high compared to that of other drugs. This study focused on children under the age of 18 years of age with ALL who received chemotherapy containing vincristine. We retrospectively analyzed the results of a nerve conduction study and a cumulative dose of vincristine in 30 children diagnosed with peripheral neuropathy. The average cumulative dose until diagnosis of vincristine-induced peripheral neuropathy was 14.99 ± 1.21 mg/m 2 , and motor nerves were predominantly involved. Additionally, a marked decrease in average amplitude was also observed in motor nerves. In addition, when the relationship between the incidence of peripheral neuropathy and the cumulative dose was analyzed through the survival curve, about 50% of children developed peripheral neuropathy at a dose of 15.5 ± 1.77 mg/m 2 . Based on the electrophysiological characteristics of pediatric vincristine-induced peripheral neuropathy, as well as the relationship between the incidence rate and the cumulative dose, it is possible to observe more closely the vincristine-induced peripheral neuropathy occurrence in children with ALL at an appropriate time.

Background: Circadian rhythm disturbance caused by shift work has adverse effects on the metabolic homeostasis of the liver. Disruption of the metabolic homeostasis of the liver causes fat accumulation in the liver. The aim of this study was to investigate the correlation between shift work and non-alcoholic fatty liver disease (NAFLD) among male workers in the steel manufacturing industry of Korea., Methods: Based on medical examination data collected in June 2020, 2,511 male subjects from one steel manufacturing company in Korea were selected in total. NAFLD was evaluated using abdominal ultrasound, which was performed by two experienced radiologists. The multinomial logistic regression analysis was performed by adjusting for age, physical activity, smoking history, alcohol consumption, body mass index, waist circumference, blood pressure, blood glucose, lipidemia, liver function test, employment duration, and hepatotoxic materials exposure status., Results: Compared to daytime workers, the odds ratio (OR) of moderate-severe NAFLD in shift workers was 1.449 (95% confidence interval [CI], 1.028-2.043). Compared to daytime workers, the ORs of moderate-severe NAFLD were significantly higher for the group that engaged in total shift work for more than 20 years (OR, 2.285; 95% CI, 1.051-4.970), the group that was not allowed to sleep during night shift work (OR, 1.463; 95% CI, 1.030-2.078), and the group that consumed food during night shift work (OR, 1.580; 95% CI, 1.093-2.284)., Conclusions: There was a correlation between shift work and moderate-severe NAFLD in male steel manufacturing workers. There will be a need for more research related to the correlation of shift work with steatohepatitis and cirrhosis in the future., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2022 Korean Society of Occupational & Environmental Medicine.)

Background: This study aimed to investigate the association between lead exposure and serum gamma-glutamyl transpeptidase (γGT) levels as an oxidative stress marker in male steelworkers., Methods: Data were collected during the annual health examination of workers in 2020. A total of 1,654 steelworkers were selected, and the variables for adjustment included the workers' general characteristics, lifestyle, and occupational characteristics. The association between the blood lead level (BLL) and serum γGT level was investigated by multiple linear and logistic regression analyses. The BLL and serum γGT values that were transformed into natural logarithms were used in multiple linear regression analysis, and the tertile of BLL was used in logistic regression analysis., Results: The geometric mean of the participants' BLLs and serum γGT level was 1.36 μg/dL and 27.72 IU/L, respectively. Their BLLs differed depending on age, body mass index (BMI), smoking status, drinking status, shift work, and working period, while their serum γGT levels differed depending on age, BMI, smoking status, drinking status, physical activity, and working period. In multiple linear regression analysis, the difference in models 1, 2, and 3 was significant, obtaining 0.326, 0.176, and 0.172 (all: p < 0.001), respectively. In the multiple linear regression analysis stratified according to drinking status, BMI, and age, BLLs were positively associated with serum γGT levels. Regarding the logistic regression analysis, the odds ratio of the third BLL tertile in models 1, 2, and 3 (for having an elevated serum γGT level within the first tertile reference) was 2.74, 1.83, and 1.81, respectively., Conclusions: BLL was positively associated with serum γGT levels in male steelworkers even at low lead concentrations (< 5 μg/dL)., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2022 Korean Society of Occupational & Environmental Medicine.)

Background: Haenyeo is a woman who has the job of collecting seafood in the Jeju Sea at an average temperature of 13°C-14°C. The purpose of this study was to examine the cold acclimatization and occupational characteristics of Haenyeo through biomarkers such as orexin and irisin related to heat generation in the body., Methods: Twenty-one Haenyeo and 25 people with similar age, body type, and body mass index were selected as the control group (Control G). In the cold exposure experiment, a climate chamber was set to 5°C and both feet were immersed in a 15°C water tank for 30 minutes. Tympanic temperature (T ty ) and skin temperature (T sk ) were measured, and the mean body temperature (mT b ) was calculated. Blood samples were collected before and immediately after the examination. Orexin and irisin levels were analyzed., Results: Orexin levels were elevated after cold stimulation from 12.17 ± 4.44 to 12.95 ± 4.53 ng/mL (Haenyeo group [Haenyeo G], p < 0.01) and 10.37 ± 3.84 to 11.25 ± 4.02 ng/mL (Control G, p < 0.001). Irisin levels were elevated after cold stimulation from 4.83 ± 2.28 to 5.36 ± 2.23 ng/mL (Haenyeo G, p < 0.001) and 3.73 ± 1.59 to 4.18 ± 2.04 ng/mL (Control G, p < 0.001). The difference between Haenyeo G and Control G values in orexin and irisin appears not only in pre-exposure but also in post-exposure ( p < 0.05)., Conclusions: Our experimental results suggest that Haenyeo G were relatively superior in cold tolerance to Control G under cold exposure conditions. Haenyeo's cold acclimatization is due to the basic differences in pyrogens regarding body temperature control such as orexin and irisin. This means that Haenyeo are advantageous for cold survival., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2022 Korean Society of Occupational & Environmental Medicine.)

This study was conducted to determine the degree of depression in family caregivers of spinal-cord-injury patients and to identify factors influencing family caregivers' depression. The final study subjects were 30 (family caregivers: 6 males and 24 females). The CES-D of family caregivers; general characteristics of spinal-cord-injury patients and family caregivers; and information on physical health, household income, leisure, social activity, family relationship, and life-in-general status of family caregiver were collected. A frequency analysis, normality test, Mann-Whitney test, Kruskal-Wallis test, Spearman Correlation analysis, hierarchical regression analysis, and spider network through a path model analysis were performed. As for the general characteristics, when the patient was economically active, the caregiver's depression was mean ± SD; 2.04 ± 0.71; otherwise, it was mean ± SD 2.86 ± 0.74, indicating that the caregiver of the non-economic activity patient was more depressed ( p = 0.013). In Model 1 of the multiple regression analysis to understand the effect on the depression of the caregiver, it was confirmed that the depression of the caregiver decreased as the family caregiver had more leisure and social activities (B = -0.718, p = 0.001). In Model 2, it was found that the depression of caregivers increased when the patient did not engage in economic activity (B = 0.438, p = 0.016). In the spider-web form through the path model analysis, as the family's economic level increased, physical health increased by B = 0.755 ( p < 0.001), and the increase in physical health (B = 0.424, p = 0.042) was, in turn, a factor in the increase of engagement in leisure and social activities. Various policies will be needed for the successful return to society of spinal-cord-injury patients by ensuring that their leisure and social activities and establishing measures to support their economical income.

Introduction: Cognitive dysfunction reduces patients' quality of life and social participation with traumatic brain injury (TBI). Computerized cognitive rehabilitation is increasingly being used for cognitive therapy in TBI patients. The purpose of this study was to investigate the influence of age on the effect of computerized cognitive rehabilitation in cognitive dysfunction after TBI., Material and Methods: A total of 34 patients with cognitive dysfunction after TBI were enrolled. Participants performed 30 sessions of computerized cognitive rehabilitation (Comcog) for 6 weeks. A cognitive evaluation was performed before and after treatment with Mini-Mental State Examination (MMSE) and Computerized Neurophyschologic Test (CNT)., Results: There were no cognitive tests that differed between the young group and the old group at baseline. However, after computerized cognitive rehabilitation, the young group showed significant improvement compared to the old group in verbal memory, visual memory, attention, and visuo-motor coordination tests. The young group showed improvement in MMSE, verbal and visual memory, and visuo-motor coordination tests after computerized cognitive rehabilitation. In contrast, the old group showed significant improvement only in MMSE and visual learning test, one of the visual memory tests., Conclusion: Our findings demonstrate that age may be an important factor related to the effect of computer cognitive rehabilitation on cognitive dysfunction after TBI. Methodologically more ordered studies with larger sample sizes are needed in the future., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Gastric adenocarcinoma is among the top causes of cancer-related death and is one of the most commonly diagnosed carcinomas worldwide. Benzyl isothiocyanate (BITC) has been reported to inhibit the gastric cancer metastasis. In our previous study, BITC induced apoptosis in AGS cells. The purpose of the present study was to investigate the effect of BITC on autophagy mechanism in AGS cells. First, the AGS cells were treated with 5, 10, or 15 μM BITC for 24 h, followed by an analysis of the autophagy mechanism. The expression level of autophagy proteins involved in different steps of autophagy, such as LC3B, p62/SQSTM1, Atg5-Atg12, Beclin1, p-mTOR/mTOR ratio, and class III PI3K was measured in the BITC-treated cells. Lysosomal function was investigated using cathepsin activity and Bafilomycin A1, an autophagy degradation stage inhibitor. Methods including qPCR, western blotting, and immunocytochemistry were employed to detect the protein expression levels. Acridine orange staining and omnicathepsin assay were conducted to analyze the lysosomal function. siRNA transfection was performed to knock down the LC3B gene. BITC reduced the level of autophagy protein such as Beclin 1, class III PI3K, and Atg5-Atg12. BITC also induced lysosomal dysfunction which was shown as reducing cathepsin activity, protein level of cathepsin, and enlargement of acidic vesicle. Overall, the results showed that the BITC-induced AGS cell death mechanism also comprises the inhibition of the cytoprotective autophagy at both initiation and degradation steps.

This study aims to investigate the difference in physiological loading on the spine in three different motions (flexion-extension, lateral bending, and axial rotation) between osteoporotic and normal spines, using finite element modelling. A three-dimensional finite element (FE) model centered on the lumbar spine was constructed. We applied two different material properties of osteoporotic and normal spines. For the FE analysis, three loading conditions (flexion-extension, lateral bending, and axial rotation) were applied. The von Mises stress was higher on the nucleus pulposus at all vertebral levels in all movements, in the osteoporosis group than in the normal group. On the annulus fibrosus, the von Mises stress increased at the level of L3-L4, L4-L5, and L5-S in the flexion-extension group and at L4-L5 and L5-S levels in the lateral bending group. The values of two motions, flexion-extension and lateral bending, increased in the L4 and L5 cortical bones. In axial rotation, the von Mises stress increased at the level of L5 of cortical bone. Additionally, the von Mises stress increased in the lower endplate of L5-S and L4-L5 in all movements, especially lateral bending. Even in the group with no increase, there was a part that received increased von Mises stress locally for each element in the three-dimensional reconstructed view of the pressure distribution in color. The von Mises stress on the lumbar region in the three loading conditions, was greater in most components of osteoporotic vertebrae than in normal vertebrae and the value was highest in the nucleus pulposus. Considering the increase in the measured von Mises stress and the local increase in the pressure distribution, we believe that these results can contribute to explaining discogenic pain and degeneration., (© 2022. The Author(s).)

We demonstrated how the photoelectrochemical (PEC) performance was enhanced by conformal deposition of an amorphous molybdenum sulfide (a-MoS x ) thin film on a nanostructured surface of black Si using atomic layer deposition (ALD). The a-MoS x is found to predominantly consist of an octahedral structure (S-deficient metallic phase) that exhibits high electrocatalytic activity for the hydrogen evolution reaction with a Tafel slope of 41 mV/dec in an acid electrolyte. The a-MoS x has a smaller work function (4.0 eV) than that of crystalline 2H-MoS 2 (4.5 eV), which induces larger energy band bending at the p-Si surface, thereby facilitating interface charge transfer. These features enabled us to achieve an outstanding kinetic overpotential of ∼0.2 V at 10 mA/cm 2 and an onset potential of 0.27 V at 1 mA/cm 2 . Furthermore, the a-MoS x layer provides superior protection against corrosion of the Si surface, enabling long-term PEC operation of more than 50 h while maintaining 87% or more performance. This work highlights the remarkable advantages of the ALD a-MoS x layer and leads to a breakthrough in the architectural design of PEC cells to ensure both high performance and stability.

In this study, we investigated the influence of galangin on vascular contractibility and to determine the mechanism underlying the relaxation. Isometric contractions of denuded aortic muscles were recorded and combined with western blot analysis which was performed to measure the phosphorylation of phosphorylation-dependent inhibitory protein of myosin phosphatase (CPI-17) and myosin phosphatase targeting subunit 1 (MYPT1) and to evaluate the effect of galangin on the RhoA/ROCK/CPI-17 pathway. Galangin significantly inhibited phorbol ester-, fluoride- and thromboxane mimetic-induced vasoconstrictions regardless of endothelial nitric oxide synthesis, suggesting its direct effect on vascular smooth muscle. Galangin significantly inhibited the fluoride-dependent increase in pMYPT1 and pCPI-17 levels and phorbol 12,13-dibutyrate-dependent increase in pERK1/2 level, suggesting repression of ROCK and MEK activity and subsequent phosphorylation of MYPT1, CPI-17 and ERK1/2. Taken together, these results suggest that galangin-induced relaxation involves myosin phosphatase reactivation and calcium desensitization, which appears to be mediated by CPI-17 dephosphorylation via not PKC but ROCK inactivation.

Few studies have examined rheumatoid arthritis (RA) risk and severity in Korean workers exposed to silica. We compared the hospitalization risk of RA between silica-exposed workers and the general Korean population. The study cohort consisted of male workers exposed to silica who had undergone at least one silica-associated special medical examination between 1 January 2000 and 31 December 2004 ( N = 149,948). The data were from the Korea Occupation Safety and Health Agency. RA morbidity based on hospital admission records was estimated from 2000 to 2005 using the Korea National Health Insurance Service claims data. The standardized admission ratio (SAR) was calculated by dividing the observed number of admissions in silica-exposed workers by the expected number of admissions in the general reference population. For the sum of "Seropositive rheumatoid arthritis" (M05) and "Other rheumatoid arthritis" (M06), the SAR was higher in the silica-exposed group (1.34, 95% CI 1.08-1.64). For M05, workers with <10 years of silica exposure had a significantly higher SAR (2.54, 95% CI 1.10-5.01) than the general population. More silica-exposed workers without a diagnosis of pneumoconiosis were hospitalized for RA than the general population. Our analysis reaffirms the link between silica exposure and RA and suggests that the severity of RA is increased by silica. Further studies of silica-exposed workers with longer follow-up are needed.

Background: Incremental peritoneal dialysis (iPD) can be useful in patients with residual renal function (RRF). RRF was well preserved and similar survival was shown in iPD compared to conventional PD (cPD) in previous study. However, the long-term survival of iPD remains unclear compared to cPD in diabetic patients. This study evaluated whether patient survival, hospitalization and peritonitis, and PD survival in iPD were lower than cPD or not., Methods: We conducted a 12-year retrospective observational study of 303 PD patients (232 cPD and 71 iPD) using propensity score matching by age, gender, and diabetes mellitus (DM). Finally, 78 cPD patients and 39 iPD patients were included and 44 patients had DM. Incremental PD was defined as starting PD with two or three manual exchanges per day., Results: The median duration of iPD was 24.1 months and iPD had higher RRF than cPD. Compared to cPD, the patient survival, PD survival and hospitalization benefits were not found in iPD but diabetic iPD patients had significantly longer survival and less hospitalization. Cumulative risk for peritonitis was lower iPD and PD duration of iPD was longer than those of cPD. The iPD was an independent factor associated with survival in patients with DM., Conclusions: Incremental PD may be a safe PD modality to initiate and maintain PD in less uremic patients with tolerable RRF. Incremental PD would be a benefit for survival in diabetic patients. Further prospective studies are necessary to confirm the effectiveness of iPD in PD patients with similar RRF.

Background: The aim of this study was to investigate the relationship between occupational exposure to various hazards and hospital admission due to endocrine diseases in Korean male firefighters., Methods: From 2000 to 2008, former and current male firefighters registered in the Korean National Emergency Management Agency were investigated based on their hospitalized health insurance admission data for the same period. Admission data for endocrine, nutritional, and metabolic diseases were obtained from the Korean National Health Insurance Service database. Standardized admission ratio (SAR) with reference to the general population of Korean men was analyzed., Results: SAR for firefighters with endocrine, nutritional, and metabolic diseases was 0.56 (95% confidence interval [CI]: 0.49-0.65), which was significantly less than that of the general population of Korean men. For those with endocrine, nutritional, and metabolic diseases, SARs for those with a history of fire suppression tasks and those without experience of fire suppression tasks were 0.58 (95% CI: 0.49-0.68) and 0.53 (95% CI: 0.40-0.70), respectively., Conclusions: The admission rate of Korean male firefighters due to endocrine, nutritional and metabolic diseases was significantly lower than that of the general Korean men population, the hazardous potential of endocrine disruptors remains an open question. Further studies of firefighters with longer follow-up are needed., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2021 Korean Society of Occupational & Environmental Medicine.)

Background: The study aimed to determine the association between shift work and metabolic syndrome and the prevalence of metabolic syndrome in the shift and day work groups among workers working in chemical plants., Methods: Based on medical examination data collected in February 2019, 3,794 workers working at a chemical plant in Korea were selected. Multiple logistic regression analysis was performed by adjusting for age, sex, body mass index (BMI), drinking, exercise, smoking, employment period and organic compounds exposure., Results: The prevalence of metabolic syndrome in the entire study group was 23.4%, and the prevalence and components of metabolic syndrome in shift worker; waist circumference were higher than those of day workers (84.77 ± 8.64 vs. 83.41 ± 9.42, p < 0.001), systolic blood pressure (129.89 ± 9.47 vs. 127.57 ± 9.47, p < 0.001), diastolic blood pressure (81.22 ± 7.59 vs. 79.34 ± 7.46, p < 0.001), fasting blood glucose (99.27 ± 17.13 vs. 97.87 ± 13.07, p = 0.007), triglycerides (149.70 ± 101.15 vs. 133.55 ± 105.17, p < 0.001), and decreased high-density lipoprotein (53.18 ± 12.82 vs. 55.61 ± 14.17, p < 0.001). As a result of logistic regression analysis on the risk of metabolic syndrome, even after adjusting for age, sex BMI, drinking, smoking, exercise, employment period, organic compound exposure. the odds ratio (OR) for the shift group was 1.300 for daytime workers (Model 1, OR: 1.491; 95% confidence interval [CI]: 1.273-1.747; Model 2, OR: 1.260; 95% CI: 1.070-1.483; Model 3, OR: 1.309, 95% CI: 1.081-1.585; Model 4, OR: 1.300; 95% CI: 1.063-1.591)., Conclusions: Shift work in chemical plant workers increased the risk of metabolic syndrome, even after adjusting for general factors. To analyze the occupational cause and risk control, it is necessary to analyze the hazardous substances the workers were exposed to and their working environment. Additionally, a large-scale prospective analysis including general factors not analyzed in this study, such as eating habits, is required., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2021 Korean Society of Occupational & Environmental Medicine.)

Competing Interests: CONFLICTS OF INTEREST: The authors have nothing to disclose.

Background: This study aimed to investigate the effect of androgen suppression therapy using leuprorelin focused on the bulbar function of patients with spinal and bulbar muscular atrophy (SBMA)., Methods: Genetically confirmed SBMA patients who consented to participate in this observational study were enrolled. Leuprorelin was subcutaneously injected every 12 weeks. Videofluoroscopic swallowing study was performed at baseline and after androgen suppression therapy for 1 year. The primary outcome measures were the changes in the vallecular residue and pyriform sinus residue. The videofluoroscopic swallowing study data were analyzed and interpreted by two experienced physiatrists., Results: A total of 40 patients with SBMA were analyzed in this study. The inter-rater reliability testing showed good agreement for the pharyngeal residue (ICC = 0.84) and videofluoroscopic dysphagia scale (ICC = 0.75). The vallecular residue and pyriform sinus residue after swallowing 9 mL yogurt were significantly reduced (26.8 ± 22.6 to 14.6 ± 14.5, p < 0.001, 14.9 ± 16.9 to 7.6 ± 9.9, p < 0.001, respectively). The swallowing subscore of amyotrophic lateral sclerosis functional rating scale-revised improved after androgen suppression therapy (3.3 ± 0.5 to 3.5 ± 0.6, p = 0.041)., Conclusions: Leuprorelin significantly reduced the pharyngeal residue in patients with SBMA after 1 year of treatment without any serious adverse events and longitudinal studies are needed to confirm these results., (© 2021. Springer-Verlag GmbH, DE part of Springer Nature.)

Background: Spinal and bulbar muscular atrophy (SBMA) is an X-lined motor neuron disease characterized by progressive muscle weakness, bulbar palsy, and dysphagia. Dysphagia is associated with tongue weakness, which is a common manifestation of SBMA. This study aimed to investigate the correlations between tongue pressure and dysphagia in patients with SBMA. Materials and Methods: Thirty-nine genetically confirmed SBMA patients underwent a videofluoroscopic swallowing study (VFSS) and tongue pressure assessment. Then, we analyzed the maximal tongue pressure (MTP), oral transit time, penetration-aspiration scale (PAS), videofluoroscopic dysphagia scale (VDS), amyotrophic lateral sclerosis functional rating scale-revised (ALSFRS-R), and 6-min walk test (6MWT). Pearson and Spearman correlation coefficients were calculated to analyze the association of the MTP with clinical, swallowing, and functional parameters. Results: In the correlation analysis, MTP was negatively correlated with disease duration ( r = -0.396, p = 0.013) and VDS ( r = -0.426, p = 0.007), and positively correlated with ALSFRS-R ( r = 0.483, p = 0.002) and 6MWT ( r = 0.396, p = 0.013). The bulbar ( r = 0.367, p = 0.022) and gross motor ( r = 0.486, p = 0.002) domains of the ALSFRS-R were correlated with MTP. Conclusion: Tongue pressure assessment can be used as a safe and easy tool to assess swallowing function in SBMA patients. Moreover, MTP reflects functional states, including activities of daily living and gait performance, showing it to be a potential biomarker for physical performance in SBMA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Gwak, Jung, Min, Park, Cho, Park, Hong and Kang.)

This study aimed to investigate the effects of blood lead levels (BLLs) and lead and cadmium exposure on endometriosis (EM). The study cohort consisted of female workers who underwent a lead-associated special medical examination between 1 January 2000 and 31 December 2004 ( n = 26,542). The standard admission rate (SAR) and admission odds ratio (OR) for EM were calculated using the general population and noise-exposed groups, respectively, for the same period as the reference standards. The SAR for EM was 1.24 (95% confidence interval (CI): 1.03-1.48) in lead-exposed workers and 1.44 (95% CI: 1.11-1.85) in workers with BLLs < 5 μg/dL when compared with that of the general population. Admission ORs of EM in lead-exposed workers and those with BLLs < 5 μg/dL were statistically higher than those of noise-exposed workers (OR, 1.40; 95% CI, 1.15-1.70 and OR, 1.48; 95% CI, 1.11-1.98, respectively). The relative excess risk due to interaction of lead and cadmium was 0.33. Lead exposure was associated with EM admission. EM admission in lead-exposed workers with BLLs < 5 μg/dL was statistically higher than that of the general population and noise-exposed workers. Co-exposure to lead and cadmium has a synergistic effect with EM.

Background: There is growing evidence that exposure to organic solvents can play a role in the etiology of rheumatoid arthritis (RA). This prospective cohort study aimed to investigate the association between RA and toluene exposure., Methods: The study cohort consisted of Korea Occupational Safety and Health Agency data from male workers exposed to toluene who had undergone a toluene-associated special medical examination at least once between January 1, 2000 and December 31, 2004 (n = 148,870). The morbidity from RA based on hospital admission records was estimated from 2000 to 2005 using National Health Insurance Claim Data. The standardized admission ratio (SAR) for RA was calculated with reference to the general population. Levels of urinary hippuric acid (HA), a metabolite of toluene, were measured and used for exposure assessment., Results: Toluene-exposed workers were at an elevated risk of seropositive rheumatoid arthritis (ICD-10 code M05) with an SAR of 2.38 (95% confidence interval [CI]: 1.14-4.37) and other rheumatoid arthritis (M06) with an SAR of 1.22 (95% CI: 0.91-1.59). When data were stratified according to the duration of toluene exposure and by tertiles of urinary HA level, no significant difference was apparent., Conclusion: SARs of the toluene-exposed workers are higher than that of the general reference population, indicating that exposure to toluene may contribute to an increased risk of RA. Further studies of toluene-exposed workers with longer follow-up are needed., (© 2021 Wiley Periodicals LLC.)

Rationale: Spinal muscular atrophy (SMA) is a genetic disorder caused by genetic defect of SMN1 gene. SMA was an untreatable disease until 2016, when Nusinersen an antisense oligonucleotide therapy was approved for treatment. We report the effect of Nusinersen in a late onset SMA for 14 months., Patient Concerns: A 13-year-old boy who was diagnosed as SMA with progressive proximal limb weakness was treated with intrathecal injection of Nusinersen., Diagnosis: The patient had progressive proximal limb weakness after 2 years of age. The patient had elevated creatine kinase level and shoed neurogenic changes in the needle electromyography study. After genetic analysis, homozygous deletion in Exon 7 and 8 of SMN1 protein was found and he was diagnosed as late onset SMA., Interventions: Intrathecal Nusinersen was administered per protocol., Outcomes: After 14 months of treatment, the patient showed significant clinical improvement in the revised Hammersmith functional rating scale and 6-minute walk test., Lessons: Although there is limited data on the effect of Nusinersen in late onset SMA patients, our case adds on the effectiveness even in late onset SMA. More studies are needed to consolidate the effects and adverse events of Nusinersen in late onset SMA., Competing Interests: The authors have no conflict of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Post-stroke depression (PSD) is a consequential neuropsychiatric sequela that occurs after stroke. However, the pathophysiology of PSD are not well understood yet., Objective: To explore alterations in functional connectivity (FC) between anterior insula and fronto-cortical and other subcortical regions in the non-affected hemisphere in patients with PSD compared to without PSD and healthy control., Methods: Resting-state FC was estimated between the anterior insula and cortical and subcortical brain regions in the non-affected hemisphere in 13 patients with PSD, 12 patients without PSD, and 13 healthy controls. The severity of depressive mood was measured by the Beck Depression Inventory (BDI)-II., Results: Patients with PSD showed significant differences in FC scores between the anterior insula and the superior frontal, middle frontal, and orbitofrontal gyrus in the non-affected hemisphere than healthy control or patients without PSD (P< 0.05). In post-hoc, patients with PSD showed higher FC scores between the anterior insula and the superior frontal region than patients without PSD (P< 0.05). Furthermore, alterations in FC of the superior frontal, middle frontal, and orbitofrontal gyrus were positively correlated with depression severity, as measured with the BDI-II (P< 0.001).

Purpose: Upper limb hemiparesis is the most common impairment in stroke survivors, and adequate assessment is crucial for setting the rehabilitation strategy and monitoring the effect of treatment. However, adequate timely assessments are difficult due to the limited accessibility to clinics for stroke survivors. We designed this study to investigate whether teleassessments for motor impairments of the spastic elbow (i.e., passive range of motion (PROM), muscle strength, and spasticity) are feasible in stroke survivors. Methods: To implement a telerobotic system for remote assessment with physical interaction, we constructed a system with a master robot interacting with a doctor (assessor) and a slave robot interacting with the elbow of a subject with stroke. The master robot is operated by the doctor, where the torque and the speed are transferred to the slave robot via the Internet, and the reaction of the patient's elbow to the slave robot's movement is measured with a torque sensor, then finally transferred back to the master robot. An intercontinental remote assessment, which is considered one of the worst possible scenarios, was used as a clinical test to strictly check the feasibility. For the clinical tests, the examiner for the teleassessment was located at a lab in the National Institutes of Health (NIH, Bethesda, MD, USA) while the stroke patients were located at Seoul National University Bundang Hospital (Bundang, Kyeonggido, South Korea). Results: In total, 12 stroke patients' elbows (age range, 28-74; M:F = 6:6) were tested. For the PROM, the absolute difference between two assessments (in-person vs. remote) was 5.98 ± 3.51° on average (range, 0-11.2). The agreements for the strength and the spasticity of elbow flexor between in-person and remote assessments were substantial ( k = 0.643) and fair ( k = 0.308), respectively. No adverse events were observed during or immediately after the telerobotic assessment. Conclusions: Internet-based telerobotic remote assessment for motor impairment of spastic elbow in stroke using our system is feasible even in the worst setting, with too long of a distance and a delayed communication network., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Kim, Sin, Kim, Min, Kim, Paik, Cho and Park.)

Background: Studies have investigated the relationship between long work hours and sleep disorders; however, they have focused on shift workers or specific workers who are at high risk of industrial accidents rather than wage workers in general. The purpose of this study is to investigate the effects of long work hours on sleep disorders among non-shift daytime wage workers., Methods: We conducted a secondary analysis of data from the 5th Korean Working Conditions Survey. From the 50,205 total participants, we included 26,522 non-shift daytime wage workers after excluding self-employed people, business owners, unpaid family employees, and wage workers who work nights and shifts. Sleep disorders were categorized into "difficulty in falling asleep," "frequent waking," and "waking up with fatigue." Logistic regression analysis was used to evaluate the influence of long work hours on sleep disorders, and the odds ratios (ORs) were calculated., Results: The OR of working > 52 hours per week was 1.183 (95% confidence interval [CI]: 1.002-1.394) for the risk of developing insomnia compared with working ≤ 40 hours per week. The OR of waking up with fatigue was 1.531 (95% CI: 1.302-1.801). Long work hours showed no significant relationship with difficulty in falling asleep or with frequent waking., Conclusions: Working for extended hours was associated with increased fatigue upon waking in non-shift daytime wage workers., Competing Interests: Competing interests: The authors declare that they have no competing interest., (Copyright © 2020 Korean Society of Occupational & Environmental Medicine.)

Background: Nusinersen has recently been approved and more widely used as first-line treatment of spinal muscular atrophy (SMA). This study aimed to evaluate the real-world experience of nusinersen use for patients with a broad spectrum of SMA., Methods: We reviewed consecutive patients with SMA treated with nusinersen from April 2018 to April 2020. Data collected included clinical and diagnostic characteristics, molecular genetics, functional motor outcomes, and adverse events., Results: Seven patients including four with SMA type 1 and three with SMA type 2 were treated with nusinersen. The median disease duration at the time of the first dose and the median follow-up duration were 37 months (range: 0.5-254 months) and 6.1 months (range: 2.1-22.1 months), respectively. Of the 41 lumbar punctures (LPs), seven fluoroscopy-guided LPs were successfully performed for two patients without sedation. All patients showed improvement in motor function even though the current tools for motor assessment seemed unable to detect subtle subjective improvement. All patients maintained a stable respiratory status. No patient has experienced a severe adverse event or discontinued treatment so far., Conclusion: Although the number of patients in this study was small, our results suggest that nusinersen is effective even in patients with a later stage of the disease. Additional long-term prospective studies with more number of patients having a broad spectrum of diseases are needed to identify meaningful improvement in the motor function and quality of life after nusinersen treatment., Competing Interests: There are no conflicts of interest., (Copyright: © 2006 - 2020 Annals of Indian Academy of Neurology.)

Introduction: We aimed to determine the optimal placement of electrodes for neuromuscular electrical stimulation (NMES) for post-stroke dysphagia therapy., Methods: 31 patients with post-stroke dysphagia were randomised to three groups according to NMES electrode placement. In Group A (n = 10), two pairs of electrodes were attached horizontally on the suprahyoid and infrahyoid muscles. In Group B (n = 11), one pair of electrodes was attached horizontally on the suprahyoid muscles while the other was attached vertically on the infrahyoid muscles. In Group C (n = 10), the electrodes were attached vertically, with one pair above the hyoid bone and the other above the cricoid cartilage. All patients received rehabilitation treatment via NMES combined with effortful swallowing training five times weekly for four weeks. The effect of NMES electrode placement was assessed in terms of the Functional Dysphagia Scale (FDS) and Dysphagia Outcome and Severity Scale (DOSS) scores., Results: Group A showed significantly greater improvement than Group B in overall FDS (p = 0.009) and pharyngeal-phase FDS (FDS-P; p = 0.005) scores. Group A also showed significant improvement when compared with Group C in overall FDS (p = 0.001) and FDS-P (p = 0.001) scores., Conclusion: Horizontal placement of the NMES electrodes on the suprahyoid and infrahyoid muscles for the treatment of post-stroke dysphagia by NMES combined with effortful swallowing was more effective than the horizontal and vertical placement of electrodes on the suprahyoid and infrahyoid muscles, respectively, and their vertical placement above the hyoid bone and cricoid cartilage., (Copyright: © Singapore Medical Association.)

Background: This study aimed to investigate the association between job stress and suicide ideation/attempts among display manufacturing workers., Methods: Data were collected from 836 workers in a display manufacturing company who participated in health screenings from May 22 to June 16, 2017. The data included general characteristics, night work, job tenure, previous physician-diagnosed chronic diseases, suicidal ideation/suicide attempts, and job stress. We investigated suicidal ideation/suicide attempts that covered the past year by using a self-reported questionnaire. Job stress was measured using the 43-item Korean Occupational Stress Scale. Multiple logistic regression analysis was used to investigate the association between job stress and suicidal ideation/suicide attempts. The mediator effect of depression on suicidal ideation/suicide attempts was tested using a series of logistic regression by applying Baron and Kenny's mediation method., Results: In the model adjusting for variables (e.g., age, body mass index, smoking, alcohol consumption, regular exercise, shift work, job tenure, chronic disease and depression), physical environment (OR: 3.60, 95% CI: 1.08-12.02), lack of reward (OR: 5.31, 95% CI: 1.54-18.34), and occupation climate (OR: 7.36, 95% CI: 2.28-23.72) were correlated with suicidal ideation/suicide attempts in women. However, all subscales of job stress were not significantly correlated with suicidal ideation/suicide attempts in men. In mediation analysis, job instability and occupational climate were correlated with suicidal ideation/suicide attempts and were mediated by depression in men workers., Conclusions: In women workers, the experiences of suicidal ideation/suicide attempts were significantly correlated with the physical environment, lack of reward, and occupational climate that were subscales of job stress. In men workers, depression rather than job stress was correlated with experiences of suicidal ideation/suicide attempts., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2020 Korean Society of Occupational & Environmental Medicine.)

We investigated changes in the cranial/cephalic index of the Korean population in millennia, centuries, and recent decades. Secular changes of Korean's cephalic index in history were studied using the data of archaeology literature and our measurement data of different adult skull sets for the fifteenth-nineteenth century Joseon people, the Korean War victims (1950-1953), and the Korean skeletons collected by medical schools in the 1960s. A change in head shape during the last century was also estimated by the analysis on Korean cephalometric datasets of Korean Research Institute of Standards and Science. In brief, over the past 2000 years, the crania of Korean people have steadily changed from mesocephalic to brachycephalic, mainly due to the cranial length shortening. Brachycephalization accelerated at the beginning of the twentieth century and continued until the early twenty-first century, largely caused by increased cephalic breadth. We also note that debrachycephalization began in birth cohorts around 1965 for males and around 1970 for females. Taken together, we figure out that the head shape of Korean people has been gradually shortened over millennia and then has undergone dramatic shortening in the last century. In recent decades, however, the changing pattern has reversed to debrachycephalization, for which we discussed about the possible causes in the present report.

Background: Sleep disorders are common and serious problems for mental health. This study investigated the relationship between spouses' weekly working hours (SWWH) and sleep problems by using the data from the 5th Korean Working Conditions Survey., Methods: Data from 14,921 wage workers were used in the 5th Korean Working Conditions Survey. General and occupational characteristics, sleep problems are included in the questionnaire. Multivariate logistic regression analysis was used after adjustment for general and occupational characteristics to find the relationship between SWWH and sleep problems., Results: Compared to those whose spouses worked less than 40 hours per week, risk of trouble falling asleep, waking up repeatedly while sleeping, and waking up with a feeling of exhaustion and fatigue was significantly higher as SWWH increase among those whose spouses worked 53 or more hours per week (odds ratio [OR]: 1.40, 95% confidence interval [CI]: 1.16-1.70; OR: 1.50, 95% CI: 1.23-1.82; OR: 1.51, 95% CI: 1.24-1.83)., Conclusions: SWWH were related to sleep problems among Korean wage workers., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2020 Korean Society of Occupational & Environmental Medicine.)

Predicting prognosis in patients with basal ganglia hemorrhage is difficult. This study aimed to investigate the usefulness of diffusion tensor imaging in predicting motor outcome after basal ganglia hemorrhage. A total of 12 patients with putaminal hemorrhage were included in the study (aged 50 ± 12 years), 8 patients were male (aged 46 ± 11 years) and 4 were female (aged 59 ± 9 years). We performed diffusion tensor imaging and measured clinical outcome at baseline (pre) and 3 weeks (post1), 3 months (post2), and 6 months (post3) after the initial treatment. In the affected side of the brain, the mean fractional anisotropy (FA) value on pons was significantly higher in the good outcome group than that in the poor outcome group at pre ( p = 0.004) and post3 ( p = 0.025). Pearson correlation analysis showed that mean FA value at pre significantly correlated with the sum of the Brunnstrom motor recovery stage scores at post3 ( R = 0.8, p = 0.002). Change in the FA ratio on diffusion tractography can predict motor recovery after hemorrhagic stroke.

This study aimed to evaluate the usefulness of interhemispheric functional connectivity (FC) as a predictor of motor recovery in severe hand impairment and to determine the cutoff FC level as a clinically useful parameter. Patients with stroke ( n = 22; age, 59.9 ± 13.7 years) who presented with unilateral severe upper-limb paresis and were confirmed to elicit no motor-evoked potential responses were selected. FC was measured using resting-state functional magnetic resonance imaging (rsfMRI) scans at 1 month from stroke onset. The good recovery group showed a higher FC value than the poor recovery group ( p = 0.034). In contrast, there was no statistical difference in FC value between the good recovery and healthy control groups ( p = 0.182). Additionally, the healthy control group showed a higher FC value than that shown by the poor recovery group ( p = 0.0002). Good and poor recovery were determined based on Brunnstrom stage of upper-limb function at 6 months as the standard, and receiver operating characteristic curve indicated that a cutoff score of 0.013 had the greatest prognostic ability. In conclusion, interhemispheric FC measurement using rsfMRI scans may provide useful clinical information for predicting hand motor recovery during stroke rehabilitation.

Background/aims: This study aimed to evaluate the correlation between clinical risk factors of post-extubation dysphagia (PED) and the severity of impaired pharyngeal swallowing function assessed via videofluoroscopic swallowing studies (VFSSs)., Methods: This study was a retrospective review of medical records. Of 116 patients who were admitted to the intensive care unit and underwent VFSS, 32 who had non-neurologic disorders and experienced prolonged intubation (for more than 48 hours) were diagnosed with PED. The severity of PED was evaluated by using a functional dysphagia scale (FDS) and a penetration aspiration scale (PAS), on the basis of VFSS., Results: The Simplified Acute Physiology Score 3 and total FDS score were positively correlated (r = 0.40, p = 0.02). Intubation duration was positively correlated with total PAS and FDS scores (r = 0.62, p < 0.001; r = 0.65, p < 0.001, respectively). The amounts of residue in the valleculae (RV) and pyriform sinuses (RP) were associated with intubation duration (r = 0.58, p < 0.001; r = 0.57, p < 0.001, respectively). Multivariate regression analysis revealed that intubation duration was significantly associated with the total FDS score, RV and RP subscales of the FDS, and total PAS score., Conclusion: The severity of impaired swallowing function, particularly the amount of residue in the pharyngeal recesses assessed via VFSS, was strongly associated with both severity of medical illness and intubation duration. Intubation duration could be a prognostic factor for assessing impaired swallowing function on the basis of VFSS.

Background: The mechanisms by which mobility function and neuropathic pain are mutually influenced by supraspinal plasticity in motor- and pain-related brain networks following spinal cord injury (SCI) remains poorly understood., Objective: To determine cortical and subcortical resting-state network alterations using power spectral density (PSD) analysis and investigate the relationships between these intrinsic alterations and mobility function and neuropathic pain following SCI., Methods: A total of 41 patients with incomplete SCI and 33 healthy controls were included. The degree of mobility and balance function and severity of neuropathic pain and depressive mood were evaluated. The resting-state functional magnetic resonance imaging data of low-frequency fluctuations were analyzed based on PSD. Differences in PSD values between patients with SCI and controls were assessed using the two-sample t-test (false discovery rate-corrected P < 0.05). The relationship between PSD values and mobility function and pain intensity was assessed using Pearson's correlation coefficient adjusted for the severity of depressive mood., Results: Compared with healthy controls, lower PSD values in supplementary motor and medial prefrontal areas (the anterior cingulate cortex, ventral medial prefrontal cortex, and superior orbito-prefrontal cortex) were associated with greater pain severity and poorer postural balance and mobility (P < 0.05) in patients with SCI, whereas higher PSD values in the primary motor cortex, premotor cortex, thalamus, and periaqueductal gray were associated with greater pain severity and poorer postural balance and mobility (P < 0.05)., Conclusions: Cortical and subcortical plastic alterations in intrinsic motor- and pain-related networks were observed in patients with SCI and were simultaneously associated with neuropathic pain intensity and degree of mobility function., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Mixed reality (MR) technology, which combines the best features of augmented reality and virtual reality, has recently emerged as a promising tool in cognitive rehabilitation therapy., Objective: To investigate the effectiveness of an MR-based cognitive training system for individuals with mild cognitive impairment (MCI)., Methods: Twenty-one individuals aged 65 years and older who had been diagnosed with MCI were recruited for this study and were divided into two groups. Participants in the MR group (n=10, aged 70.5±4.2 years) received 30 minutes of training 3 times a week for 6 weeks using a newly developed MR-based cognitive training system. Participants in the control group (n=11, aged 72.6±5.3 years) received the same amount of training using a conventional computer-assisted cognitive training system. Both groups took the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) both before and after intervention. To determine the effect of the intervention on cognitive function, we compared the difference in each group's CERAD-K scores., Results: There was a statistically significant interaction between intervention (MR group vs control group) and time (before vs after intervention) as assessed by the Constructional Recall Test. The individuals with MCI who participated in the MR training showed significantly improved performance in visuospatial working memory compared with the individuals with MCI who participated in the conventional training., Conclusion: An MR-based cognitive training system can be used as a cognitive training tool to improve visuospatial working memory in individuals with MCI.

Purpose: Recently, the international agency for research on cancer recommended that methanol should be recognized as a medium-priority, human cancer risk. Therefore, we performed an epidemiological study to evaluate the relationship between methanol exposure and the cancer mortality of Korean workers occupationally exposed to methanol., Methods: The study cohort was composed of methanol-exposed 25,218 male workers, data on whom were available from the Korea Occupational Safety and Health Agency; all participants underwent methanol-associated medical check-ups at least once between January 2000 and December 2004. The durations of methanol exposure were categorized as < 10, 10-20, and ≥ 20 years. Workplace methanol exposure levels for each worker were divided into three grades. We compared their standardized cancer mortality rates (SMRs) to those of the general population. Intra-cohort hazard ratios were estimated using a Cox's proportional hazards model., Results: We found no positive association between methanol exposure and cancer mortality. In terms of all cancer mortality, methanol-exposed workers exhibited significantly lower SMRs than the general population. In terms of other cancer mortality, no significant difference or trend was evident as a function of duration of methanol exposure., Conclusions: Although we found no significant correlation between methanol exposure and cancer mortality, we believe the work is meaningful; this is the first, large-scale, human epidemiological study. The carcinogenic potential of methanol remains an open question, and studies with longer-term follow-up periods are needed.

Study Design: Retrospective study., Purpose: Associations among risk factors related to adjacent segmental disease (ASD) remain unclear. We evaluated the risk factors and segmental lordosis ratio to prevent ASD developing after lumbar spinal fusion., Overview of Literature: Risk factors related to ASD development are age, sex, obesity, pre-existing degeneration, number of fusion segments, and decreased postoperative lumbar lordosis (LL). However, the associations among these factors are still unclear and should be clearly identified., Methods: We retrospectively reviewed data on 274 patients who underwent lumbar spinal fusion of three segments or below for lumbar degenerative disease from January 2010 to December 2012, with over 5 years of follow-up. Patients with preoperative sagittal vertical axis (SVA) >5 cm were excluded due to sagittal imbalance. A total of 37 patients with ASD and 40 control patients (CTRL) were randomly selected in a similar distribution of matching variables: age, sex, and preoperative degenerative changes. Sex, age, number of fusion segments, radiologic measurements, L4-5-S1/L1-S1 LL ratio, and spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], sacral slope [SS], and SVA) were analyzed. Logistic regression was used to analyze the correlation between PI-LL mismatch and L4-5-S1 segmental lordosis rate., Results: No significant difference was found between ASDs and CTRL groups regarding age, sex, number of fusion segments, fusion method, and preoperative and postoperative spinopelvic parameters (PI, SS, PT, and LL). However, regarding the L4-5-S1/L1-S1 lordosis ratio, 50% (p=0.045), 60% (p=0.031), 70% (p=0.042), 80% (p=0.023), and 90% (p=0.023) were statistically significant; <20% (p=0.478), 30% (p=0.223), and 40% (p=0.089) were not statistically significant. In the postoperative PI-LL <10 group, ASD occurred less frequently than in the PI-LL >10 group, and the difference was statistically significant (p=0.048)., Conclusions: Patients with a postoperative L4-5-S1/L1-S1 lordosis ratio >50% had less occurrence of ASD. Correcting LL according to PI and physiologic segmental lordosis ratio is important in preventing ASD.

Our study aimed to investigate the effects of the polysaccharide-rich extract of Phragmites rhizoma (PEP) against water immersion restraint (WIR) stress and forced swimming-induced fatigue. Exposure to WIR stress significantly increased the ulcer index, bleeding score, the weight of the adrenal gland, blood glucose concentrations, total cholesterol, cortisol, and creatine kinase (CK). The weight of the spleen decreased significantly. In addition, myeloperoxidase (MPO) and thiobarbituric acid-reactive substance (TBARS) were significantly upregulated by WIR stress. The antioxidative factors such as glutathione (GSH) and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the stomach were decreased by WIR stress. Alterations induced by WIR stress were effectively reversed by pretreatment with PEP. The swimming endurance capacity of mice was significantly prolonged by the oral administration of PEP. Swimming-induced fatigue significantly reduced the body weight; however, the injection of PEP inhibited the decrease of body weight. The PEP-treated group had significantly lower CK levels in plasma, an indicator of muscle damage. These results indicated that PEP has anti-stress and anti-fatigue effects, which are mediated by suppressing the hyperactivation of the hypothalamus-pituitary-adrenal axis, and antagonism of the oxidative damages induced by WIR stress and prolonged swimming times.

Background: Prognostic measures of long-term motor recovery are important in patients with stroke presenting with severe hemiplegia., Objective: We aimed to investigate whether initial power spectral density (PSD) analysis of resting-state functional magnetic resonance (fMRI) data can provide a sensitive prognostic predictor in patients with subacute stroke with severe hand disability., Methods: Twelve patients with good recovery, 14 patients with poor recovery, and 12 healthy subjects were included. PSD analysis was performed using resting-state fMRI data. Contralesional and ipsilesional PSD in the motor cortex were measured. Pearson correlation analysis was performed to assess a possible association between the difference in ipsilesional versus contralesional PSD and motor outcomes. A receiver operating characteristic (ROC) curve was constructed to estimate the discriminative value of the difference between the ipsilesional PSD and the contralesional PSD for good versus poor recovery., Results: There were no differences in PSD between the contralesional and ipsilesional hemispheres in the good recovery group ( P = .77). In contrast, there were significant differences in PSD between the 2 hemispheres in the poor recovery group ( P = .07). The difference in PSD between the 2 hemispheres had a positive correlation with post Brunnstrom stage scores. ROC analysis showed that the difference in PSD between the 2 hemispheres was sensitive in discriminating good versus poor recovery., Conclusion: The present study suggests that PSD in the motor cortex may be a sensitive predictor of late-onset motor recovery following stroke.