Background and Objectives: Accumulating evidence shows that sodium-glucose cotransporter 2 inhibitors (SGLT2is) reduce adverse cardiovascular outcomes. However, whether SGLT2i, compared with other antidiabetic drugs, reduce the new development of atrial fibrillation (AF) is unclear. In this study, we compared SGLT2i with dipeptidyl peptidase-4 inhibitors (DPP-4is) in terms of reduction in the risk of AF in individuals with type 2 diabetes. Methods: We included 42,786 propensity score-matched pairs of SGLT2i and DPP-4i users without previous AF diagnosis using the Korean National Health Insurance Service database between May 1, 2016, and December 31, 2018. Results: During a median follow-up of 1.3 years, SGLT2i users had a lower incidence of AF than DPP-4i users (1.95 vs. 2.65 per 1,000 person-years; hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.55–0.97; p=0.028]). In individuals without heart failure, SGLT2i users was associated with a decreased risk of AF incidence (HR, 0.70; 95% CI, 0.52–0.94; p=0.019) compared to DPP-4i users. However, individuals with heart failure, SGLT2i users was not significantly associated with a change in risk (HR, 1.04; 95% CI, 0.44–2.44; p=0.936). Conclusions In this nationwide cohort study of individuals with type 2 diabetes, treatment with SGLT2i was associated with a lower risk of AF compared with treatment with DPP-4i.

Myosin heavy chain 9 (MYH9) related diseases are autosomal dominant diseases characterized by macrothrombocytopenia and inclusion bodies in leukocyte, which can be accompanied by extra-hematologic symptoms such as sensorineural hearing loss, renal dysfunction, and cataract. They are often diagnosed incidentally in adulthood or misdiagnosed as idiopathic thrombocytopenic purpura (ITP), leading to unnecessary treatment with intravenous high-dose gamma-globulin, steroids, or splenectomy. Here, we report the case of a brother and sister confirmed to have a MYH9 gene mutation during follow-up. An 8-year-old boy was confirmed to have thrombocytopenia at birth and treated with intravenous gamma-globulin under suspicion of ITP or sepsis. He was discharged after showing an increase in platelet count. Subsequently, during outpatient workup, he exhibited thrombocytopenia, large platelets, and neutrophilic inclusion bodies. His 10-year-old sister also presented with the same findings. In 2021, DNA analysis revealed that they share a mutation (c.4270G> A, p. Asp1424Asn), a pathogenic variant associated with MYH9-related disorder.

Background: There is insufficient data on the benefits of empiric antibiotic combinations for hospital-acquired pneumonia (HAP). We aimed to investigate whether empiric antipseudomonal combination therapy with fluoroquinolones decreases mortality in patients with HAP. Methods: This multicenter, retrospective cohort study included adult patients admitted to 16 tertiary and general hospitals in Korea between January 1 and December 31, 2019.Patients with risk factors for combination therapy were divided into anti-pseudomonal non-carbapenem β-lactam monotherapy and fluoroquinolone combination therapy groups.Primary outcome was 30-day mortality. Propensity score matching (PSM) was used to reduce selection bias. Results: In total, 631 patients with HAP were enrolled. Monotherapy was prescribed in 54.7% (n = 345) of the patients, and combination therapy was prescribed in 45.3% (n = 286).There was no significant difference in 30-day mortality between the two groups (16.8% vs.18.2%, P = 0.729) or even after the PSM (17.5% vs. 18.2%, P = 0.913). After the PSM, adjusted hazard ratio for 30-day mortality from the combination therapy was 1.646 (95% confidence interval, 0.782–3.461; P = 0.189) in the Cox proportional hazards model. Moreover, there was no significant difference in the appropriateness of initial empiric antibiotics between the two groups (55.0% vs. 56.8%, P = 0.898). The proportion of multidrug-resistant (MDR) pathogens was high in both groups. Conclusion Empiric anti-pseudomonal fluoroquinolone combination therapy showed no survival benefit compared to β-lactam monotherapy in patients with HAP. Caution is needed regarding the routine combination of fluoroquinolones in the empiric treatment of HAP patients with a high risk of MDR.

Background: A study on coronavirus disease 2019 (COVID-19) phobia among students revealed that fear of contracting COVID-19 was associated with commuting to school and spending time with others at school. Therefore, it is the need-of-the-hour for the Korean government to identify factors affecting COVID-19 phobia among university students and to consider these factors while framing the policy direction for the process of returning to normalcy in university education. Consequently, we aimed to identify the current state of COVID-19 phobia among Korean undergraduate and graduate students and the factors affecting COVID-19 phobia. Methods: This cross-sectional survey was conducted to identify the factors affecting COVID-19 phobia among Korean undergraduate and graduate students. The survey collected 460 responses from April 5 to April 16, 2022. The questionnaire was developed based on the COVID-19 Phobia Scale (C19P-S). Multiple linear regression was performed on the C19P-S scores using five models with the following dependent variables: Model 1, total C19P-S score; Model 2, psychological subscale score; Model 3, psychosomatic subscale score; Model 4, social subscale score; and Model 5, economic subscale score. The fit of these five models was established, and a P-value of less than 0.05 (F test) was considered statistically significant. Results: An analysis of the factors affecting the total C19P-S score led to the following findings: women significantly outscored men (difference: 4.826 points, P = 0.003); the group that favored the government’s COVID-19 mitigation policy scored significantly lower than those who did not favor it (difference: 3.161 points, P = 0.037); the group that avoided crowded places scored significantly higher than the group that did not avoid crowded places (difference: 7.200 points, P < 0.001); and those living with family/friends scored significantly higher than those in other living situations (difference: 4.606 points, P = 0.021). Those in favor of the COVID-19 mitigation policy had significantly lower psychological fear than those who were against it (difference: -1.686 points, P = 0.004). Psychological fear was also significantly higher for those who avoided crowded places compared to those who did not difference: 2.641 points, P < 0.001). Fear was significantly higher in people cohabitating than those living alone (difference: 1.543 points, P= 0.043). Conclusion The Korean government, in their pursuit of a policy that eases COVID-19-related restrictions, will also have to spare no efforts in providing correct information to prevent the escalation of COVID-19 phobia among people with a high fear of contracting the disease. This should be done through trustworthy information sources, such as the media, public agencies, and COVID-19 professionals.

Subclinical hypothyroidism (SCH), characterized by elevated serum thyroid-stimulating hormone (TSH) levels and normal free thyroxine levels, usually presents without symptoms, and is often discovered incidentally during routine blood test. The Task Force of the Korean Thyroid Association Committee of Clinical Practice Guidelines has established a guideline to evaluate and manage SCH; the guideline emphasizes the implementation of diagnostic criteria based on the TSH reference range for Koreans and focuses on the proven health benefits of levothyroxine (LT4) treatment. Based on the Korea National Health and Nutrition Examination Survey (2013-2015), serum TSH level of 6.8 mIU/L is considered the reference value for SCH. SCH can be categorized as mild (TSH 6.8-10.0 mIU/L) or severe (TSH ＞10.0 mIU/L), and patients are classified as adults (age ＜70 years) or elderly patients (age ≥70years) depending on the health effects of LT4 treatment. An initial increase in serum TSH levels should be reassessed with a subsequent measurement, along with the thyroid peroxidase antibody test, preferably 2-3 months after the initial evaluation. Usually, LT4 treatment is not recommended for mild SCH in adults; however, treatment is necessary for severe SCH in patients with underlying coronary artery disease or heart failure and can be considered for coexisting dyslipidemia. LT4 treatment is not recommended for mild or even severe SCH in elderly patients, in general. Patients with SCH who receive LT4 treatment, the LT4 dosage should be personalized, and serum TSH levels should be monitored to ensure optimal LT4 dosage (dosage that is neither excessive nor insufficient). Patients with SCH who do not receive LT4 treatment require periodic follow-up at appropriate testing intervals determined by disease severity. The guideline also provides several educational points applicable in clinical settings.

Melanogenesis is the production of melanin from tyrosine by a series of enzyme-catalyzed reactions, in which tyrosinase and DOPA oxidase play key roles. The melanin content in the skin determines skin pigmentation. Abnormalities in skin pigmentation lead to various skin pigmentation disorders. Recent research has shown that the expression of EMP2 is much lower in melanoma than in normal melanocytes, but its role in melanogenesis has not yet been elucidated. Therefore, we investigated the role of EMP2 in the melanogenesis of MNT1 human melanoma cells. We examined TRP-1, TRP-2, and TYR expression levels during melanogenesis in MNT1 melanoma cells by gene silencing of EMP2. Western blot and RT-PCR results confirmed that the expression levels of TYR and TRP-2 were decreased when EMP2 expression was knocked down by EMP2 siRNA in MNT1 cells, and these changes were reversed when EMP2 was overexpressed. We verified the EMP2 gene was knocked out of the cell line (EMP2 CRISPR/Cas9) by using a CRISPR/Cas9 system and found that the expression levels of TRP-2 and TYR were significantly lower in the EMP2 CRISPR/Cas9 cell lines. Loss of EMP2 also reduced migration and invasion of MNT1 melanoma cells. In addition, the melanosome transfer from the melanocytes to keratinocytes in the EMP2 KO cells cocultured with keratinocytes was reduced compared to the cells in the control coculture group. In conclusion, these results suggest that EMP2 is involved in melanogenesis via the regulation of TRP-2 expression.

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.

Objective: The purpose of this study was to investigate the differences in the characteristics between rental car crashes and non-rental car crashes on Jeju Island, and to investigate the association between rental car crashes and the severity of injuries. Methods: This study analyzed data on traffic accidents that occurred on Jeju Island, South Korea from January 2010 to December 2019. The data on traffic accident-related factors were collected using the Traffic Accident Analysis System operated by the Road Traffic Authority. The primary outcome was a fatal injury and secondary outcomes were severe and minor injuries. We analyzed the differences in the characteristics of each factor between rental car crashes and nonrental crashes. We also analyzed the correlation between rental car accidents and the outcome variables. Results: A total of 40,713 traffic accidents occurred during the study period, of which 4,601 (11.3%) were rental car crashes and 36,112 (88.7%) were non-rental crashes. In the rental car crash group, the proportions of the 20-30s age group and female drivers were higher; however, the proportion of the risky driving behaviors was lower. Also, the incidence rate in summer and daytime was higher, and the proportions of vehicle-to-vehicle crashes, single vehicle crashes, and head-on collisions were higher. According to the results of the Poisson regression test, the rental car crash group showed a higher risk of severe injuries (adjusted incidence rate ratio, 1.07; 95% confidence interval, 1.01-1.14), but there was no significant difference in their risk of fatal injuries. Conclusion Our results suggest the need for traffic accident prevention programs considering the characteristics of rental car crashes on Jeju Island, South Korea.