Objectives: The purpose of this study was to compare the fracture strength and traslucency of 3D printing resin crowns according to different thicknesses. Methods: Resin crowns were designed with CAD software and a 3D scanner, using scanned data of the #61 tooth model. Resin Crowns with different thicknesses were printed using a 3D printer, and subsequently divided into four groups according to thickness (0.3, 0.5, 0.7, and 1.0 mm). Fracture strength was compared among groups with a resin strip crown of 1.0 mm thickness. Compressive force was applied using a universal testing machine at 30° along the lingual surface at 1 mm/min cross head speed. For translucency evaluation, thin square specimens were printed of thicknesses 0.3, 0.5, 0.7, and 1.0 mm, and translucency was measured using a spectrophotometer. Results: As a result of fracture strength measurement, fracture strength increased as thickness increased, and a significant difference was observed solely between thicknesses of 0.3 and 0.5 mm, and the thicknesses of 0.3 and 0.5 mm (P<0.05). Translucency decreased as thickness increased, and similarly, a significant difference was observed only between thicknesses of 0.3 and 0.5 mm and the thicknesses of 0.7 and 1.0 mm (P<0.05). Conclusions A 3D printing resin crown can be used as a clinical option for restoring a primary anterior tooth affected by caries.

Coronavirus disease 2019 (COVID-19) vaccination may non-specifically alter the host immune system. This study aimed to evaluate the effect of COVID-19 vaccination on hepatitis B surface Ag (HBsAg) titer and host immunity in chronic hepatitis B (CHB) patients. Consecutive 2,797 CHB patients who had serial HBsAg measurements during antiviral treatment were included in this study. Changes in the HBsAg levels after COVID-19 vaccination were analyzed. The dynamics of NK cells following COVID-19 vaccination were also examined using serial blood samples collected prospectively from 25 healthy volunteers. Vaccinated CHB patients (n=2,329) had significantly lower HBsAg levels 1–30 days post-vaccination compared to baseline (median, −21.4 IU/ml from baseline), but the levels reverted to baseline by 91–180 days (median, −3.8 IU/ml). The velocity of the HBsAg decline was transiently accelerated within 30 days after vaccination (median velocity: −0.06, −0.39, and −0.04 log 10 IU/ml/year in pre-vaccination period, days 1–30, and days 31–90, respectively). In contrast, unvaccinated patients (n=468) had no change in HBsAg levels. Flow cytometric analysis showed that the frequency of NK cells expressing NKG2A, an NK inhibitory receptor, significantly decreased within 7 days after the first dose of COVID-19 vaccine (median, −13.1% from baseline; p<0.001). The decrease in the frequency of NKG2A + NK cells was observed in the CD56dimCD16+ NK cell population regardless of type of COVID-19 vaccine. COVID-19 vaccination leads to a rapid, transient decline in HBsAg titer and a decrease in the frequency of NKG2A + NK cells.

Purpose: A critical indicator of the overall survival of patients with high-grade glioma is the successful isolation of tumor mesenchymal stem-like cells (tMSLCs), which play important roles in glioma progression. However, attempts to isolate tMSLCs from surgical specimens have not always been successful, and the reasons for this remain unclear. Considering that the amount of surgical high-grade glioma specimens varies, we hypothesized that larger surgical specimens would be better for tMSLC isolation. Materials and Methods: We assessed 51 fresh, high-grade glioma specimens and divided them into two groups according to the success or failure of tMSLC isolation. The success of tMSLC isolation was confirmed by plastic adherence, presenting antigens, tri-lineage differentiation, and non-tumorigenicity. Differences in characteristics between the two groups were tested using independent two sample t-tests, chi-square tests, or Kaplan-Meier survival analysis. Results: The mean specimen weights of the groups differed from each other (tMSLC-negative group: 469.9±341.9 mg, tMSLC positive group: 546.7±618.9 mg), but the difference was not statistically significant. The optimal cut-off value of specimen weight was 180 mg, and the area under the curve value was 0.599. Conclusion Our results suggested a minimum criterion for specimen collection, and found that the specimen amount was not deeply related to tMSLC detection. Collectively, our findings imply that the ability to isolate tMSLCs is determined by factors other than the specimen amount.

Purpose: A critical indicator of the overall survival of patients with high-grade glioma is the successful isolation of tumor mesenchymal stem-like cells (tMSLCs), which play important roles in glioma progression. However, attempts to isolate tMSLCs from surgical specimens have not always been successful, and the reasons for this remain unclear. Considering that the amount of surgical high-grade glioma specimens varies, we hypothesized that larger surgical specimens would be better for tMSLC isolation. Materials and Methods: We assessed 51 fresh, high-grade glioma specimens and divided them into two groups according to the success or failure of tMSLC isolation. The success of tMSLC isolation was confirmed by plastic adherence, presenting antigens, tri-lineage differentiation, and non-tumorigenicity. Differences in characteristics between the two groups were tested using independent two sample t-tests, chi-square tests, or Kaplan-Meier survival analysis. Results: The mean specimen weights of the groups differed from each other (tMSLC-negative group: 469.9±341.9 mg, tMSLC positive group: 546.7±618.9 mg), but the difference was not statistically significant. The optimal cut-off value of specimen weight was 180 mg, and the area under the curve value was 0.599. Conclusion Our results suggested a minimum criterion for specimen collection, and found that the specimen amount was not deeply related to tMSLC detection. Collectively, our findings imply that the ability to isolate tMSLCs is determined by factors other than the specimen amount.

PURPOSE: This study aimed to identify multidimensional factors influencing burnout in intensive care unit(ICU) nurses. METHODS: A descriptive cross-sectional design was used. Data were collected during February 2016 from a convenience sample of 222 tertiary hospital ICU nurses and analyzed using t-test, ANOVA, correlation analysis, and multiple regression analysis. RESULTS: Burnout correlated positively with compassion fatigue (CF)(r=.37, p < .001), and negatively with compassion satisfaction (CS)(r=-.66, p < .001). The regression model explained 57% of the variance in burnout. For individual characteristics in the model, perceived health status (β=-.27, p < .001) and gender (β=.14, p=.028) were the most influential factors for ICU nurses' burnout. In the model with added work-related characteristics, nursing environment (β=-.22, p=.001), perceived health status (β=-.20, p=.001), and satisfaction with department (β=-.19, p=.007) were the most influential factors. Finally, for the model with psychological characteristics added, CS (β=-.56, p < .001) and CF (β=.35, p < .001) were the most influential factors. CONCLUSION: Results reveal that most ICU nurses have a moderate level of CF and a moderate to high level of CS and burnout, and that individual, work-related and psychological factors are relevant in ICU nurses' burnout. Programs or interventions to reduce burnout should be developed taking into account these multidimensional factors.
Compassion Fatigue ; Critical Care ; Empathy ; Intensive Care Units ; Nursing ; Personal Satisfaction ; Psychology ; Tertiary Care Centers

BACKGROUND/AIMS: Commercially available sodium hyaluronate solutions are usually too thick to inject through catheters and need dilution with normal saline (NS) before use, which increases the risk of contamination. We evaluated the usefulness of ready-to-use 0.4% sodium hyaluronate, Endo-Ease (EE; UNIMED Pharm. Inc., Seoul, Korea). METHODS: We performed a prospective multicenter randomized study from May 2011 to September 2012. Patients requiring endoscopic resection (ER) for gastric or colorectal neoplasm at two referral hospitals were enrolled. RESULTS: One hundred fifty-four patients (72 with a gastric neoplasm and 82 with a colorectal neoplasm) were included in intention-to-treat analysis. Thirty-seven gastric neoplasms and 43 colorectal neoplasms were enrolled in the EE group. The usefulness rate was significantly higher in the EE group than in the NS group (89.2% vs. 60.0% for gastric neoplasms and 95.3% vs. 67.7% for colorectal neoplasms, p<0.001). In the EE group, the ease of mucosal resection was significantly higher than in the NS group (p<0.001). The injected volume was smaller in the EE group than in the NS group (p<0.05). CONCLUSIONS: The use of EE reduced the need for additional injections and improved the ease of ER. A submucosal injection of EE is useful for the ER of both gastric and colorectal neoplasms.
Catheters ; Colorectal Neoplasms ; Gastrointestinal Neoplasms* ; Humans ; Hyaluronic Acid* ; Prospective Studies ; Referral and Consultation ; Seoul ; Sodium* ; Stomach Neoplasms

BACKGROUND/AIMS: Second-look endoscopy is performed to check for the possibility of post-endoscopic submucosal dissection (ESD) bleeding and to perform prophylactic hemostasis in most hospitals; however, there is little evidence about the efficacy of second-look endoscopy. We investigated whether second-look endoscopy after ESD is useful in the prevention of post-ESD bleeding. METHODS: A total of 550 lesions with gastric epithelial neoplasms in 502 patients (372 men and 130 women) were treated with ESD between August 18, 2009 and August 18, 2010. After the exclusion of three lesions of post-ESD bleeding within 24 hours, 547 lesions (335 early gastric cancers and 212 gastric adenomas) were included for the final analysis. RESULTS: The occurrence rate of delayed post-ESD bleeding was not significantly different between the second-look group and the no second-look group (1% vs 2.5%, p>0.05). The only predictor of delayed bleeding was tumor size, regardless of second-look endoscopy after ESD (22.8+/-9.87 vs 15.1+/-10.47, p<0.05). There was no difference between the prophylactic hemostasis and nonprophylactic hemostasis groups, including the occurrence rate of delayed bleeding. In the second-look group with prophylactic hemostasis, the hospital stay was more prolonged than in the second-look group without prophylactic hemostasis, but there was no significant difference (p=0.08). CONCLUSIONS: Second-look endoscopy to prevent delayed bleeding after ESD provides no significant medical benefits.
Adult ; Aged ; Aged, 80 and over ; Female ; Gastrectomy/adverse effects ; Gastric Mucosa/surgery ; *Gastroscopy ; Humans ; Length of Stay ; Male ; Middle Aged ; Postoperative Hemorrhage/*diagnosis/etiology ; Retrospective Studies ; Risk Factors ; Second-Look Surgery ; Stomach/pathology/surgery ; Stomach Neoplasms/pathology/*surgery ; Time Factors

BACKGROUND/AIMS: We started a daily web-based E-mail learning program about gastrointestinal (GI) endoscopy. We surveyed the opinion of the E-mail recipients about the usefulness of the daily E-mail learning program. MATERIALS AND METHODS: Using the intranet system, PDF-file based education materials about interesting endoscopic cases were sent to 144 members of Samsung Medical Center every day. It included every resident of the Department of Medicine, and every fellow of the Division of Gastroenterology. They were invited to answer the questionnaires using E-mail. RESULTS: A total of 92 subjects replied the questionnaire (response rate: 64%). About half of the members (47%) answered that they read the education material in the morning. They answered that they read about more than 75% of the material (48%). It took less than 5 minutes to read a daily material (87%). However, only 13 percent answered that they have sent questions to the editor of the program via E-mail. The members wanted more information about GI pharmacologic treatment (54%). Also, they wanted more cases of benign and malignant upper GI diseases (54%). CONCLUSIONS: In our endoscopy unit, we have successfully established a daily E-mail learning program. It seems to be very useful for teaching and learning interesting cases during busy working hours.
Computer Communication Networks* ; Education ; Electronic Mail* ; Endoscopy ; Gastroenterology ; Learning*

BACKGROUND/AIMS: The aim of this study was to investigate the frequency of disseminated gastric mucosa-associated lymphoid tissue (MALT) lymphoma and the role of bone marrow study in the initial staging work-up. METHODS: A total of 194 patients with gastric MALT lymphoma was enrolled. The incidence of disseminated disease was evaluated in the initial staging work-up. The demographic data and tumor characteristics were compared according to Helicobacter pylori infection status. RESULTS: Localized disease of Lugano stage I accounted for 97.4% of the enrolled cases. Abdominal computed tomography revealed abdominal lymph node metastasis in five patients (2.6%). Bone marrow (BM) involvement was found in only one patient without H. pylori infection (0.5%). No patient showed positive findings on chest computed tomography or positron emission tomography. H. pylori-negative cases showed a significantly higher frequency of advanced-stage disease than H. pylori-positive cases (10.0% vs 0.6%). In patients achieving complete remission, no extragastric recurrence occurred during follow-up. CONCLUSIONS: The incidence of disseminated disease, including BM involvement, was very low in Korean gastric MALT lymphoma patients. It might be beneficial to perform BM aspiration and biopsy as a part of staging work-up only in patients with risk factors for advanced disease such as H. pylori negativity.
Abdomen ; Adult ; Aged ; Bone Marrow/*pathology ; Bone Marrow Examination ; Cohort Studies ; Female ; Helicobacter Infections/*complications ; Humans ; Lymph Nodes/*radiography ; Lymphoma, B-Cell, Marginal Zone/complications/*pathology ; Male ; Mediastinum/radiography ; Middle Aged ; Neoplasm Staging ; Radiography, Abdominal ; Republic of Korea ; Retrospective Studies ; Stomach Neoplasms/complications/*pathology ; Tomography, X-Ray Computed

BACKGROUND/OBJECTIVES: Although preclinical studies suggest that garlic has potential preventive effects on cardiovascular disease (CVD) risk factors, clinical trials and reports from systematic reviews or meta-analyses present inconsistent results. The contradiction might be attributed to variations in the manufacturing process that can markedly influence the composition of garlic products. To investigate this issue further, we performed a meta-analysis of the effects of garlic powder on CVD risk factors. MATERIALS/METHODS: We searched PubMed, Cochrane, Science Direct and EMBASE through May 2014. A random-effects meta-analysis was performed on 22 trials reporting total cholesterol (TC), 17 trials reporting LDL cholesterol (LDL-C), 18 trials reporting HDL cholesterol (HDL-C), 4 trials reporting fasting blood glucose (FBG), 9 trials reporting systolic blood pressure (SBP) and 10 trials reporting diastolic blood pressure (DBP). RESULTS: The overall garlic powder intake significantly reduced blood TC and LDL-C by -0.41 mmol/L (95% confidence interval [CI], -0.69, -0.12) (-15.83 mg/dL [95% CI, -26.64, -4.63]) and -0.21 mmol/L (95% CI, -0.40, -0.03) (-8.11 mg/dL [95% CI, -15.44, -1.16]), respectively. The mean difference in the reduction of FBG levels was -0.96 mmol/L (95% CI, -1.91, -0.01) (-17.30 mg/dL [95% CI, -34.41, -0.18]). Evidence for SBP and DBP reduction in the garlic supplementation group was also demonstrated by decreases of -4.34 mmHg (95% CI, -8.38, -0.29) and -2.36 mmHg (95% CI, -4.56, -0.15), respectively. CONCLUSIONS: This meta-analysis provides consistent evidence that garlic powder intake reduces the CVD risk factors of TC, LDL-C, FBG and BP.
Blood Glucose ; Blood Pressure ; Cardiovascular Diseases ; Cholesterol ; Cholesterol, HDL ; Cholesterol, LDL ; Fasting ; Garlic* ; Risk Factors*