Purpose: Ductal carcinoma In Situ (DCIS) is common in South Korea. We evaluated the patterns of axillary surgery among patients with DCIS to highlight the need for compliance with the updated national guidelines. We also evaluated whether sentinel lymph node biopsy (SLNB) was performed in accordance with the national guidelines. Methods: The Korean Health Insurance Review and Assessment Service-National Inpatient Sample database was searched for patients with DCIS (2009–2015) to identify axillary surgery patterns by breast surgery type, year of diagnosis, age at diagnosis, and the location and volume of surgeries for DCIS at the hospital. The rates of SLNB and axillary dissection were compared using descriptive statistics and univariate analyses. Analyses were also conducted using the chi-squared test and multiple logistic regression analysis. Results: We identified 16,315 Korean women who underwent surgery for DCIS, including 11,292 cases of SLNB (69.2%) and 131 cases of axillary lymph node dissection (0.8%).Breast-conserving surgery (BCS) was performed in 10,323 patients (63.3%) with an SLNB rate of 56.0%, while total mastectomy (TM) was performed in 5,992 patients (36.7%), with an SLNB rate of 92.0%. During 2009–2015, the SLNB rate during TM increased from 88.23% to 92.80%. SLNB was influenced by hospital region and surgical volume, and hospitals performing low volumes of surgeries were significantly more likely to perform SLNB regardless of the surgery type (odds ratio, 1.372; 95% confidence interval, 1.265–1.488). Conclusion Although the Korean guidelines recommend SLNB for all TM procedures and select BCS procedures for DCIS, relatively high rates of SLNB were performed for BCS, and there was inter-hospital variability in performing SLNB. Improved compliance with the guidelines by the surgeons is critical for Korean patients with DCIS.

Purpose: Ductal carcinoma In Situ (DCIS) is common in South Korea. We evaluated the patterns of axillary surgery among patients with DCIS to highlight the need for compliance with the updated national guidelines. We also evaluated whether sentinel lymph node biopsy (SLNB) was performed in accordance with the national guidelines. Methods: The Korean Health Insurance Review and Assessment Service-National Inpatient Sample database was searched for patients with DCIS (2009–2015) to identify axillary surgery patterns by breast surgery type, year of diagnosis, age at diagnosis, and the location and volume of surgeries for DCIS at the hospital. The rates of SLNB and axillary dissection were compared using descriptive statistics and univariate analyses. Analyses were also conducted using the chi-squared test and multiple logistic regression analysis. Results: We identified 16,315 Korean women who underwent surgery for DCIS, including 11,292 cases of SLNB (69.2%) and 131 cases of axillary lymph node dissection (0.8%).Breast-conserving surgery (BCS) was performed in 10,323 patients (63.3%) with an SLNB rate of 56.0%, while total mastectomy (TM) was performed in 5,992 patients (36.7%), with an SLNB rate of 92.0%. During 2009–2015, the SLNB rate during TM increased from 88.23% to 92.80%. SLNB was influenced by hospital region and surgical volume, and hospitals performing low volumes of surgeries were significantly more likely to perform SLNB regardless of the surgery type (odds ratio, 1.372; 95% confidence interval, 1.265–1.488). Conclusion Although the Korean guidelines recommend SLNB for all TM procedures and select BCS procedures for DCIS, relatively high rates of SLNB were performed for BCS, and there was inter-hospital variability in performing SLNB. Improved compliance with the guidelines by the surgeons is critical for Korean patients with DCIS.

This study aimed to evaluate the long-term outcomes of teeth treated with reattachment technique in children and adolescents. Twenty seven permanent anterior teeth from 21 patients treated with fragment reattachment were evaluated. Clinical photos and medical records were used to assess treatment outcomes. Effect of pulp treatment and the ratio of fragment on success rate were statistically analyzed. Detachment of fragment was observed in 17 teeth, and their duration of retention was 21.41 ± 23.39 months. Repeated trauma was found to be the most frequent causes of failure. Pulp treatment before reattachment did not affect the success rate (p > 0.05). The mean ratio of fragment was 0.482 ± 0.147, and the success rate was affected by the ratio of fragment (p = 0.018). The median retention time of the teeth was 72 months if the ratio was under 0.5, and 8 months for that of the others. A significant correlation was found between the ratio of fragment and retention time (p = 0.003). Reattachment can be a predictable treatment option for crown fracture in anterior teeth in children and adolescents when a fracture involves less than 50% of the clinical crown.

Background: Low-density lipoprotein cholesterol is an important marker highly associated with cardiovascular disease. Since the direct measurement of it is inefficient in terms of cost and time, it is common to estimate through the Friedewald equation developed about 50 years ago. However, various limitations exist since the Friedewald equation was not designed for Koreans. This study proposes a new low-density lipoprotein cholesterol estimation equation for South Koreans using nationally approved statistical data. Methods: This study used data from the Korean National Health and Nutrition Examination Survey from 2009 to 2019. The 18,837 subjects were used to develop the equation for estimating low-density lipoprotein cholesterol. The subjects included individuals with low-density lipoprotein cholesterol levels directly measured among those with high-density lipoprotein cholesterol, triglycerides, and total cholesterol measured. We compared twelve equations developed in the previous studies and the newly proposed equation (model 1) developed in this study with the actual low-density lipoprotein cholesterol value in various ways. Results: The low-density lipoprotein cholesterol value estimated using the estimation formula and the actual low-density lipoprotein cholesterol value were compared using the root mean squared error. When the triglyceride level was less than 400 mg/dL, the root mean squared of the model 1 was 7.96, the lowest compared to other equations, and the model 2 was 7.82. The degree of misclassification was checked according to the NECP ATP III 6 categories. As a result, the misclassification rate of the model 1 was the lowest at 18.9%, and Weighted Kappa was the highest at 0.919 (0.003), which means it significantly reduced the underestimation rate shown in other existing estimation equations. Root mean square error was also compared according to the change in triglycerides level. As the triglycerides level increased, the root mean square error showed an increasing trend in all equations, but it was confirmed that the model 1 was the lowest compared to other equations. Conclusion The newly proposed low-density lipoprotein cholesterol estimation equation showed significantly improved performance compared to the 12 existing estimation equations. The use of representative samples and external verification is required for more sophisticated estimates in the future.

OBJECTIVES: This study was conducted to elucidate the effects of an air quality warning system (AQWS) implemented in January 2015 in Korea by analyzing changes in the incidence and exacerbation rates of environmental diseases. METHODS: Data from patients with environmental diseases were extracted from the National Health Insurance Service-National Sample Cohort database from 2010 to 2019, and data on environmental risk factors were acquired from the AirKorea database. Patient and meteorological data were linked based on residential area. An interrupted time series analysis with Poisson segmented regression was used to compare the rates before and after AQWS introduction. Adjustment variables included seasonality, air pollutants (carbon monoxide, nitrogen dioxide, sulfur dioxide, particulate matter less than 10 μm in diameter, and ozone), temperature, and humidity. RESULTS: After AQWS implementation, the incidence of asthma gradually decreased by 20.5%. Cardiovascular disease and stroke incidence also significantly decreased (by 34.3 and 43.0%, respectively). However, no immediate or gradual decrease was identified in the exacerbation rate of any environmental disease after AQWS implementation. Sensitivity analyses were performed according to age, disability, and health insurance coverage type. Overall, the AQWS effectively mitigated the occurrence of most environmental diseases in Korea. However, the relationships between alarm system implementation and reduced incidence differed among diseases based on the characteristics of vulnerable and sensitive individuals. CONCLUSIONS Our results suggest that by tailoring the AQWS to demographic and sociological characteristics and providing enhanced education about the warning system, interventions can become an efficient policy tool to decrease air pollution-related health risks.

Information on precise effects of deflazacort on bone cell function, especially osteoclasts, is quite limited. Therefore, the present study was undertaken to test effects of deflazacort on osteoclast-like cell formation in mouse bone marrow cultures and on the regulation of osteoprotegerin (OPG) and its ligand (RANKL) mRNA expressions by RT-PCR in the ST2 marrow stromal cells. TRAP-positive mononuclear cells increased after the treatment of deflazacort at 10(-9) to 10(-7) M alone for 6 days in a dose-dependent manner. Number of TRAP-positive multi-nucleated cells (MNCs) increased significantly with combined treatment of deflazacort at 10(-7) M and 1,25-(OH)2D3 at 10(-9) M compared to that of cultures treated with 1,25-(OH)2D3 alone (p<0.05). Exposure to deflazacort at 10(-7) M in the presence of 1,25-(OH)2D3 at 10(-9) M in the last 3-day culture had greater stimulatory effect on osteoclast-like cell formation than that of the first 3-day culture did. Deflazacort at 10(-10) -10(-6) M downregulated OPG and upregulated RANKL in mRNA levels in a dose-dependent manner. These observations suggest that deflazacort stimulate osteoclast precursor in the absence of 1,25-(OH)2D3 and enhance differentiation of osteoclasts in the presence of 1,25-(OH)2D3. These effects are, in part, thought to be mediated by the regulation of the expression of OPG and RANKL mRNA in marrow stromal cells.
Animal ; Bone Marrow Cells/*cytology ; Calcitriol/pharmacology ; Calcium Channel Agonists/pharmacology ; Carrier Proteins/*genetics ; Cell Differentiation/drug effects ; Cells, Cultured ; Dexamethasone/pharmacology ; Gene Expression/drug effects ; Glucocorticoids, Synthetic/pharmacology ; Glycoproteins/*genetics ; Immunosuppressive Agents/*pharmacology ; Male ; Membrane Glycoproteins/*genetics ; Mice ; Mice, Inbred ICR ; Osteoclasts/*cytology ; Pregnenediones/*pharmacology ; RNA, Messenger/analysis ; Receptors, Cytoplasmic and Nuclear/*genetics ; Stromal Cells/cytology