Objectives: Presenteeism is known to be a much more economically damaging social cost than disease rest while going to work despite physical pain. Since COVID-19, social discussions on the sickness benefit have been taking place as a countermeasure against presenteeism, and in particular, farmers and fishermen do not have an institutional mechanism for livelihood support when a disease other than work occurs. This study attempted to examine the relationship between agricultural, fishing, and forestry workers and presenteeism using the 6th Korean Work Conditions Survey. Methods: From October 2020 to January 2021, data from the 6th working conditions survey conducted on 17 cities and provinces in Korea were used, and a total of 34,981 people were studied. Control variables were gender, age, self-health assessment, education level, night work, shift work, monthly income, occupation, working hours per week, and employment status. Results: As a result of the analysis, farmers and fishermen showed the characteristics of the self-employed and the elderly, and as a result of the regression analysis, when farmers and fishermen analyzed the relationship with presenteeism tendency compared to other industry workers, farmers and fishermen increased by 23% compared to other industry groups. Conclusion This study is significant in that it has representation by utilizing the 6th working conditions survey and objectively suggests the need for a sickness benefit for farmers and fishermen who may be overlooked in the sickness benefit.

Objectives: Presenteeism is known to be a much more economically damaging social cost than disease rest while going to work despite physical pain. Since COVID-19, social discussions on the sickness benefit have been taking place as a countermeasure against presenteeism, and in particular, farmers and fishermen do not have an institutional mechanism for livelihood support when a disease other than work occurs. This study attempted to examine the relationship between agricultural, fishing, and forestry workers and presenteeism using the 6th Korean Work Conditions Survey. Methods: From October 2020 to January 2021, data from the 6th working conditions survey conducted on 17 cities and provinces in Korea were used, and a total of 34,981 people were studied. Control variables were gender, age, self-health assessment, education level, night work, shift work, monthly income, occupation, working hours per week, and employment status. Results: As a result of the analysis, farmers and fishermen showed the characteristics of the self-employed and the elderly, and as a result of the regression analysis, when farmers and fishermen analyzed the relationship with presenteeism tendency compared to other industry workers, farmers and fishermen increased by 23% compared to other industry groups. Conclusion This study is significant in that it has representation by utilizing the 6th working conditions survey and objectively suggests the need for a sickness benefit for farmers and fishermen who may be overlooked in the sickness benefit.

Objectives: Presenteeism is known to be a much more economically damaging social cost than disease rest while going to work despite physical pain. Since COVID-19, social discussions on the sickness benefit have been taking place as a countermeasure against presenteeism, and in particular, farmers and fishermen do not have an institutional mechanism for livelihood support when a disease other than work occurs. This study attempted to examine the relationship between agricultural, fishing, and forestry workers and presenteeism using the 6th Korean Work Conditions Survey. Methods: From October 2020 to January 2021, data from the 6th working conditions survey conducted on 17 cities and provinces in Korea were used, and a total of 34,981 people were studied. Control variables were gender, age, self-health assessment, education level, night work, shift work, monthly income, occupation, working hours per week, and employment status. Results: As a result of the analysis, farmers and fishermen showed the characteristics of the self-employed and the elderly, and as a result of the regression analysis, when farmers and fishermen analyzed the relationship with presenteeism tendency compared to other industry workers, farmers and fishermen increased by 23% compared to other industry groups. Conclusion This study is significant in that it has representation by utilizing the 6th working conditions survey and objectively suggests the need for a sickness benefit for farmers and fishermen who may be overlooked in the sickness benefit.

Background: Fractional flow reserve (FFR) based on computed tomography (CT) has been shown to better identify ischemia-causing coronary stenosis. However, this current technology requires high computational power, which inhibits its widespread implementation in clinical practice. This prospective, multicenter study aimed at validating the diagnostic performance of a novel simple CT based fractional flow reserve (CT-FFR) calculation method in patients with coronary artery disease. Methods: Patients who underwent coronary CT angiography (CCTA) within 90 days and invasive coronary angiography (ICA) were prospectively enrolled. A hemodynamically significant lesion was defined as an FFR ≤ 0.80, and the area under the receiver operating characteristic curve (AUC) was the primary measure. After the planned analysis for the initial algorithm A, we performed another set of exploratory analyses for an improved algorithm B. Results: Of 184 patients who agreed to participate in the study, 151 were finally analyzed.Hemodynamically significant lesions were observed in 79 patients (52.3%). The AUC was 0.71 (95% confidence interval [CI], 0.63–0.80) for CCTA, 0.65 (95% CI, 0.56–0.74) for CT-FFR algorithm A (P = 0.866), and 0.78 (95% CI, 0.70–0.86) for algorithm B (P = 0.112). Diagnostic accuracy was 0.63 (0.55–0.71) for CCTA alone, 0.66 (0.58–0.74) for algorithm A, and 0.76 (0.68–0.82) for algorithm B. Conclusion This study suggests the feasibility of automated CT-FFR, which can be performed on-site within several hours. However, the diagnostic performance of the current algorithm does not meet the a priori criteria for superiority. Future research is required to improve the accuracy.

Background and Objectives: The aim of this study was to demonstrate the efficacy and safety of treatment with drug-coated balloon (DCB) in a large real-world population. Methods: Patients treated with DCBs were included in a multicenter observational registry that enrolled patients from 18 hospitals in Korea between January 2009 and December 2017. The primary outcome was target lesion failure (TLF) defined as a composite of cardiovascular death, target vessel myocardial infarction, and clinically indicated target lesion revascularization at 12 months. Results: The study included 2,509 patients with 2,666 DCB-treated coronary artery lesions (1,688 [63.3%] with in-stent restenosis [ISR] lesions vs. 978 [36.7%] with de novo lesions).The mean age with standard deviation was 65.7±11.3 years; 65.7% of the patients were men.At 12 months, the primary outcome, TLF, occurred in 179 (6.7%), 151 (8.9%), 28 (2.9%) patients among the total, ISR, and de novo lesion populations, respectively. A history of hypertension, diabetes, acute coronary syndrome, previous coronary artery bypass graft, reduced left ventricular ejection fraction, B2C lesion and ISR lesion were independent predictors of 12 months TLF in the overall study population. Conclusions This large multicenter DCB registry study revealed the favorable clinical outcome of DCB treatment in real-world practice in patient with ISR lesion as well as small de novo coronary lesion.

Background and Objectives: This study aimed to investigate the association between cardiovascular events and 2 different levels of elevated on-treatment diastolic blood pressures (DBP) in the presence of achieved systolic blood pressure targets (SBP). Methods: A nation-wide population-based cohort study comprised 237,592 patients with hypertension treated. The primary endpoint was a composite of cardiovascular death, myocardial infarction, and stroke. Elevated DBP was defined according to the Seventh Report of Joint National Committee (JNC7; SBP <140 mmHg, DBP ≥90 mmHg) or to the 2017 American College of Cardiology/American Heart Association (ACC/AHA) definitions (SBP <130 mmHg, DBP ≥80 mmHg). Results: During a median follow-up of 9 years, elevated on-treatment DBP by the JNC7 definition was associated with an increased risk of the occurrence of primary endpoint compared with achieved both SBP and DBP (adjusted hazard ratio [aHR], 1.14; 95% confidence interval [CI], 1.05–1.24) but not in those by the 2017 ACC/AHA definition. Elevated ontreatment DBP by the JNC7 definition was associated with a higher risk of cardiovascular mortality (aHR, 1.42; 95% CI, 1.18–1.70) and stroke (aHR, 1.19; 95% CI, 1.08–1.30). Elevated on-treatment DBP by the 2017 ACC/AHA definition was only associated with stroke (aHR, 1.10;95% CI, 1.04–1.16). Similar results were seen in the propensity-score-matched cohort. Conclusion Elevated on-treatment DBP by the JNC7 definition was associated a high risk of major cardiovascular events, while elevated DBP by the 2017 ACC/AHA definition was only associated with a higher risk of stroke. The result of study can provide evidence of DBP targets in subjects who achieved SBP targets.

Background/Aims: To evaluate the effectiveness and safety of direct acting antivirals (DAAs) available in chronic kidney disease (CKD) patients with hepatitis C virus (HCV) infection in Korea. Methods: In a retrospective, multicenter cohort study, 362 patients were enrolled from 2015 to 2019. The effectiveness and safety of DAAs including glecaprevir/pibrentasvir, sofosubvir/ribavirin, ledipasvir/sofosbuvir, and daclatasvir/asunaprevir were analyzed for patients according to CKD stage. We evaluated sustained virologic response at week 12 after treatment (SVR12) as primary endpoint. The effectiveness and safety were also evaluated according to CKD stage. Results: Among 362 patients, 307 patients completed DAAs treatment and follow-up period after end of treatment. The subjects comprised 87 patients (62 with CKD stage 3 and 25 with CKD stage (4–5), of whom 22 were undergoing hemodialysis). HCV patients with CKD stage 1 and 2 (estimated glomerular filtration rate [eGFR] ≥ 60 mL/min/1.73 m2) showed SVR12 of 97.2% and 95.4% respectively. SVR12 of CKD stage 3 and 4–5 (eGFR < 60 mL/min/1.73 m2) patients was 91.9% and 91.6% respectively. Patients undergoing hemodialysis achieved SVR12 (90.9%). Treatment failure of DAAs in stage 1, 2, 3, and 4–5 was 2.8%, 2.7%, 1.6%, and 4%. DAAs showed good safety profile and did not affect deterioration of renal function. Conclusions DAAs shows comparable SVR12 and safety in CKD patients (stage 3, 4, and 5) with HCV compared with patients with stage 1 and 2. The effectiveness and safety of DAAs may be related to the treatment duration. Therefore, it is important to select adequate regimens of DAAs and to increase treatment adherence.

BACKGROUND: Melanogenesis is a biological process resulting in the production of melanin pigment, which plays an important role in the prevention of sun-induced skin injury and determines the hair and skin color. Melanin has the ability to block ultraviolet radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. Hence, various approaches have been proposed to increase the synthesis of melanin. METHODS: The current study aimed to develop a three-dimensional hair follicle-like tissue (HFLT) model with human dermal papilla, melanocytes, and outer root sheaths cells. This model showed enhanced melanogenesis-related protein expression after rice bran ash extract (RBE) treatment. Next, we investigated the melanogenic effect of RBE in the HFLT and compared the results to those of hair follicle (HF) organ culture model. RESULTS: RBE was found to significantly increase the expression of microphthalmia-associated transcription factor, a key transcription factor involved in melanin production, in both HFLT and organ culture models. Results showed that melanogenesis-related protein expression levels were higher in the RBE group compared to those in the control group. Similar results were obtained by immunohistochemistry. CONCLUSION Our data suggested that RBE promotes melanin biosynthesis. Taken together, this simple in vitro HFLT model system has the potential to provide significant insights into the underlying molecular mechanisms of HF melanogenesis, and hence can be used for controlled evaluation of the efficacy of new materials for melanogenesis.

BACKGROUND: Melanogenesis is a biological process resulting in the production of melanin pigment, which plays an important role in the prevention of sun-induced skin injury and determines the hair and skin color. Melanin has the ability to block ultraviolet radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. Hence, various approaches have been proposed to increase the synthesis of melanin. METHODS: The current study aimed to develop a three-dimensional hair follicle-like tissue (HFLT) model with human dermal papilla, melanocytes, and outer root sheaths cells. This model showed enhanced melanogenesis-related protein expression after rice bran ash extract (RBE) treatment. Next, we investigated the melanogenic effect of RBE in the HFLT and compared the results to those of hair follicle (HF) organ culture model. RESULTS: RBE was found to significantly increase the expression of microphthalmia-associated transcription factor, a key transcription factor involved in melanin production, in both HFLT and organ culture models. Results showed that melanogenesis-related protein expression levels were higher in the RBE group compared to those in the control group. Similar results were obtained by immunohistochemistry. CONCLUSION Our data suggested that RBE promotes melanin biosynthesis. Taken together, this simple in vitro HFLT model system has the potential to provide significant insights into the underlying molecular mechanisms of HF melanogenesis, and hence can be used for controlled evaluation of the efficacy of new materials for melanogenesis.

While recently extending that research, however, the authors discovered that 236 members of the general population were mistakenly to be duplicated by the investigating agency (Word Research) and 1,241 were reported rather than 1,005. The authors present corrections and discuss the relevant data. The authors wish to apologize to the publisher and readers of Journal of Korean Medical Science for these errors.