Objectives: The purpose of this study is to analyze the relationship between dental school students’admission scores and their grade point average (GPA) after admission, as well as the relationship between student admission scores at dental school and continuation into the residency program. Methods: This study analyzed data collected from students who entered dental school between 2013 and 2017. The outcome variables were dental school GPA and continuation into residency program. Explanatory variables included admission type (early decision admission/regular admission), academic achievements (undergraduate GPA, Dental Education Eligibility Test [DEET], Test of English Proficiency [TEPS], screening by document review, and in-depth interview score), age, sex, college alma mater, high school alma mater, college major, as well as students’ academic performance in dental school. Regression analysis was performed to determine which factors relating to dental school admissions score had an influence on academic performance in dental school, whereas logistic regression analysis was conducted to determine the students’ decision to pursue a residency. Results: Students who were foreign college graduates, majored in health sciences, accepted on the basis of early decision admission, female, or had a higher college GPA showed higher dental school GPA with statistical significance. Additionally, the likelihood of students pursuing residency was found to be higher in students who were female, of younger age, college graduates in Jeolla Provinces, or who had a higher dental school GPA. Conclusions To ensure regional equality of dental service quality, it is essential that high quality students pursue residency training. For further improvement of dental school, this study’s results can be used as a reference to make students coming from other regions pursue the residency program and contribute to the regional community.

Objective: We implemented a novel resectable myocardial model for mock myectomy using a hybrid method of threedimensional (3D) printing and silicone molding for patients with apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: From January 2019 through May 2020, 3D models from three patients with ApHCM were generated using the end-diastolic cardiac CT phase image. After computer-aided designing of measures to prevent structural deformation during silicone injection into molding, 3D printing was performed to reproduce anatomic details and molds for the left ventricular (LV) myocardial mass. We compared the myocardial thickness of each cardiac segment and the LV myocardial mass and cavity volumes between the myocardial model images and cardiac CT images. The surgeon performed mock surgery, and we compared the volume and weight of the resected silicone and myocardium. Results: During the mock surgery, the surgeon could determine an ideal site for the incision and the optimal extent of myocardial resection. The mean differences in the measured myocardial thickness of the model (0.3, 1.0, 6.9, and 7.3 mm in the basal, midventricular, apical segments, and apex, respectively) and volume of the LV myocardial mass and chamber (36.9 mL and 14.8 mL, 2.9 mL and -9.4 mL, and 6.0 mL and -3.0 mL in basal, mid-ventricular and apical segments, respectively) were consistent with cardiac CT. The volume and weight of the resected silicone were similar to those of the resected myocardium (6 mL [6.2 g] of silicone and 5 mL [5.3 g] of the myocardium in patient 2; 12 mL [12.5 g] of silicone and 11.2 mL [11.8 g] of the myocardium in patient 3). Conclusion Our 3D model created using hybrid 3D printing and silicone molding may be useful for determining the extent of surgery and planning surgery guided by a rehearsal platform for ApHCM.

Objective: We implemented a novel resectable myocardial model for mock myectomy using a hybrid method of threedimensional (3D) printing and silicone molding for patients with apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: From January 2019 through May 2020, 3D models from three patients with ApHCM were generated using the end-diastolic cardiac CT phase image. After computer-aided designing of measures to prevent structural deformation during silicone injection into molding, 3D printing was performed to reproduce anatomic details and molds for the left ventricular (LV) myocardial mass. We compared the myocardial thickness of each cardiac segment and the LV myocardial mass and cavity volumes between the myocardial model images and cardiac CT images. The surgeon performed mock surgery, and we compared the volume and weight of the resected silicone and myocardium. Results: During the mock surgery, the surgeon could determine an ideal site for the incision and the optimal extent of myocardial resection. The mean differences in the measured myocardial thickness of the model (0.3, 1.0, 6.9, and 7.3 mm in the basal, midventricular, apical segments, and apex, respectively) and volume of the LV myocardial mass and chamber (36.9 mL and 14.8 mL, 2.9 mL and -9.4 mL, and 6.0 mL and -3.0 mL in basal, mid-ventricular and apical segments, respectively) were consistent with cardiac CT. The volume and weight of the resected silicone were similar to those of the resected myocardium (6 mL [6.2 g] of silicone and 5 mL [5.3 g] of the myocardium in patient 2; 12 mL [12.5 g] of silicone and 11.2 mL [11.8 g] of the myocardium in patient 3). Conclusion Our 3D model created using hybrid 3D printing and silicone molding may be useful for determining the extent of surgery and planning surgery guided by a rehearsal platform for ApHCM.

BACKGROUND: Busulfan, an alkylating agent administered prior to hematopoietic stem cell transplantation, has a narrow therapeutic range and wide variability in metabolism. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for rapid and accurate quantification of plasma busulfan. METHODS: Busulfan was separated and detected using an LC system containing a C18 column equipped with MS/MS. The sample was eluted with a mobile phase gradient for a total run time of 10 min. Plasma busulfan concentration was quantified against a 6-point standard curve in a multiple reaction monitoring mode at mass-to-charge (m/z) 264.1 > 151.1. Precision, recovery, matrix effect, linearity, detection capability, carryover, and stability were evaluated. The range of plasma busulfan concentration was obtained by analyzing samples from 9 children receiving busulfan. RESULTS: The coefficients of variation of within-run and within-laboratory precision were all below 5%. Recoveries were all within the range of 100-105%. Linearity was verified from 0 to 5,000 ng/mL. Limit of detection and limit of quantification were 1.56 and 25 ng/mL, respectively. Carryover rate was within allowable limits. Plasma busulfan concentration was stable for 2 weeks at -20degrees C and -80degrees C, but decreased by 25% when the plasma was stored for 24 hr at room temperature, and by <5% in 24 hr at 4degrees C. The plasma busulfan concentrations were between 347 ng/mL and 5,076 ng/mL. CONCLUSIONS: Our method using LC-MS/MS enables highly accurate, reproducible, and rapid busulfan monitoring with minimal sample preparation. The method may also enable safe and proper dosage.
Busulfan/*blood/standards ; Child ; Child, Preschool ; *Chromatography, High Pressure Liquid/standards ; Hematopoietic Stem Cell Transplantation ; Humans ; Infant ; Quality Control ; Reference Standards ; *Tandem Mass Spectrometry/standards