Background: The purpose of this study was to evaluate the clinical and radiological outcomes of high-flexion total knee arthroplasty (TKA) using Vega Knee System (B. Braun, Aesculap) at a long-term follow-up and to analyze the implant survivorship. Methods: We enrolled 165 patients (232 knees) with a minimum 7-year follow-up after TKA (VEGA Knee System). For clinical assessment, range of motion (ROM), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) were used. For radiologic assessment, hip-knee-ankle angle, component position, and the existence of radiolucent lines and loosening were used. Survival analysis was conducted using the Kaplan-Meier method. Results: The mean follow-up period was 9.8 years. The mean ROM increased from 124.4° to 131.4° at the final follow-up. The WOMAC score decreased from 38.5 to 17.4 at the final follow-up (p < 0.001). All 5 subscales of the KOOS improved at the final follow-up (all subscales, p < 0.001). Revision TKA was performed in 10 cases (4.3%), which included 9 cases of aseptic loosing and 1 case of periprostatic joint infection. Of the 9 aseptic loosening cases (3.9%), 8 cases (3.4%) were loosening of the femoral component and 1 case (0.4%) was loosening of the tibial component. When revision for any reason was considered an endpoint, the 10-year survivorship was 96.2% (95% confidence interval [CI], 93.9%–98.5%). On the other hand, when revision for aseptic loosening was considered the endpoint, the 10-year survivorship was 96.6% (95% CI, 94.4%–98.8%). Conclusions The Vega Knee System provided good clinical results in the long-term follow-up period. Although the VEGA Knee System showed acceptable implant survivorship, loosening of the femoral component occurred in about 3.4% of the patients. For more accurate evaluation of the survivorship of high-flexion design TKA with a short posterior flange, it is necessary to conduct more long-term follow-up studies targeting diverse races, especially Asians who frequently perform high-flexion activities.

Methods: 150 amyloid brain PET images were visually assessed by experts and categorized as negative and positive. Standardized uptake value ratio (SUVR) was calculated with cerebellum grey matter as the reference region, and receiver operating characteristic (ROC) and precision-recall (PR) analysis for BTXBrain-Amyloid were conducted. For comparison, same image processing and analysis was performed using Statistical Parametric Mapping (SPM) program. In addition, to evaluate the spatial normalization (SN) performance, mutual information (MI) between MRI template and spatially normalized PET images was calculated and SPM group analysis was conducted. Results: Both BTXBrain and SPM methods discriminated between negative and positive groups. However, BTXBrain exhibited lower SUVR standard deviation (0.06 and 0.21 for negative and positive, respectively) than SPM method (0.11 and 0.25). In ROC analysis, BTXBrain had an AUC of 0.979, compared to 0.959 for SPM, while PR curves showed an AUC of 0.983 for BTXBrain and 0.949 for SPM. At the optimal cut-off, the sensitivity and specificity were 0.983 and 0.921 for BTXBrain and 0.917 and 0.921 for SPM12, respectively. MI evaluation also favored BTXBrain (0.848 vs. 0.823), indicating improved SN. In SPM group analysis, BTXBrain exhibited higher sensitivity in detecting basal ganglia differences between negative and positive groups. Conclusion BTXBrain-Amyloid outperformed SPM in clinical performance evaluation, also demonstrating superior SN and improved detection of deep brain differences. These results suggest the potential of BTXBrain-Amyloid as a valuable tool for clinical amyloid PET image evaluation.

Purpose: In the latest staging system of the American Joint Committee on Cancer for intrahepatic cholangiocarcinoma (IHCCC), solitary tumors with vascular invasion and multiple tumors are grouped together as T2. However, recent studies report that multifocal IHCCC has a worse prognosis than a single lesion. This study aimed to investigate the risk factors for IHCCC and explore the prognostic significance of multiplicity after surgical resection. Materials and Methods: A total of 257 patients underwent surgery for IHCCC from 2010 to 2019 and the clinicopathological data were retrospectively reviewed. Risk factor analysis was performed to identify variables associated with survival after resection. Survival outcomes were compared between patients with solitary and multiple tumors. Results: In multivariable analysis, the presence of preoperative symptoms, tumor size, lymph node ratio, multiplicity, and tumor differentiation were identified as risk factors for survival. Among 82 patients with T2, overall survival was significantly longer in patients with solitary tumors (sT2) than in those with multiple tumors (mT2) (p=0.017). Survival was compared among patients with stage II-sT2, stage II-mT2, and stage III. The stage II-sT2 group showed prolonged survival when compared with stage II-mT2 or stage III. Survivals of stage II-mT2 and stage III patients were not statistically different. Conclusion Tumor multiplicity was an independent risk factor for overall survival of IHCCC after surgical resection. Patients with multiple tumors showed poorer survival than patients with a single tumor. The oncologic significance of multiplicity in IHCCC should be reappraised and reflected in the next staging system update.

This study aimed to compare the surface characteristics and the shear bond strength of veneering porcelain of 3D printed 4Y-TZP with milled 4Y-TZP. Thirty disks with 10 mm diameter and 1.2 mm thickness were fabricated. Fifteen were fabricated by 3D printing (Experimental group), and another 15 by milling (Control group). In each group, five were assigned to surface analysis. Surface roughness was measured using a confocal laser microscope. Surface energy was calculated by measuring the contact angles of water and diiodo-methane with a drop-shape analyzer. Another ten specimens were used to evaluate the shear bonding strength of veneering porcelain on the surface of 4Y-TZP. The surface of 3D-printed 4Y-TZP was very smooth, and the surface roughness (Ra, Rq) was significantly lower than that of milled 4Y-TZP (p<0.001). 3D-printed 4Y-TZP showed low wettability compared with milled 4Y-TZP, i.e., the water contact angle was significantly high (p=0.008), and the surface free energy was low (p=0.008). The shear bond strength to veneered porcelain of 3D printed 4Y-TZP was significantly lower than that of milled 4Y-TZP (p<0.001). The surface characteristics of 4Y-TZP were quite different by the manufacturing process. The smooth surface and low wettability of 3D-printed 4Y-TZP could affect its low shear bonding strength to veneering porcelain.

Background: As the coronavirus disease 2019 (COVID-19) pandemic continues, there are concerns regarding waning immunity and the emergence of viral variants. The immunogenicity of Ad26.COV2.S against wild-type (WT) and variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) needs to be evaluated.Method: This prospective cohort study was conducted between June 2021 and January 2022 at two university hospitals in South Korea. Healthy adults who were scheduled to be vaccinated with Ad26.COV2.S were enrolled in this study. The main outcomes included anti-spike (S) IgG antibody and neutralizing antibody responses, S-specific T-cell responses (interferon-γ enzyme-linked immunospot assay), solicited adverse events (AEs), and serious AEs. Results: Fifty participants aged ≥ 19 years were included in the study. Geometric mean titers (GMTs) of anti-S IgG were 0.4 U/mL at baseline, 5.2 ± 3.0 U/mL at 3–4 weeks, 55.7 ± 2.4 U/mL at 5–8 weeks, and 81.3 ± 2.5 U/mL at 10–12 weeks after vaccination. GMTs of 50% neutralizing dilution (ND50) against WT SARS-CoV-2 were 164.6 ± 4.6 at 3-4 weeks, 313.9 ± 3.6 at 5–8 weeks, and 124.4 ± 2.6 at 10–12 weeks after vaccination. As for the S-specific T-cell responses, the median number of spot-forming units/10 6 peripheral blood mononuclear cell was 25.0 (5.0–29.2) at baseline, 60.0 (23.3–178.3) at 5-8 weeks, and 35.0 (13.3–71.7) at 10–12 weeks after vaccination. Compared to WT SARS-CoV-2, ND50 against Delta and Omicron variants was attenuated by 3.6-fold and 8.2-fold, respectively. The most frequent AE was injection site pain (82%), followed by myalgia (80%), fatigue (70%), and fever (50%). Most AEs were grade 1–2, and resolved within two days. Conclusion Single-dose Ad26.COV2.S was safe and immunogenic. NAb titer and S-specific T-cell immunity peak at 5–8 weeks and rather decrease at 10–12 weeks after vaccination.Cross-reactive neutralizing activity against the Omicron variant was negligible.

Background: Gaucher disease (GD) is an autosomal recessive disorder characterized by excessive accumulation of glucosylceramide in multiple organs. This study was performed to determine the detection rate of GD in a selected patient population with unexplained splenomegaly in Korea. Methods: This was a multicenter, observational study conducted at 18 sites in Korea between December 2016 and February 2020. Adult patients with unexplained splenomegaly were enrolled and tested for β-glucosidase enzyme activity on dried blood spots (DBS) and in peripheral blood leukocytes. Mutation analysis was performed if the test was positive or indeterminate for the enzyme assay. The primary endpoint was the percentage of patients with GD in patients with unexplained splenomegaly. Results: A total of 352 patients were enrolled in this study (male patients, 199; mean age, 48.42 yr). Amongst them, 14.77% of patients had concomitant hepatomegaly. The most common sign related to GD was splenomegaly (100%), followed by thrombocytopenia (44.32%) and, anemia (40.91%). The β-glucosidase activity assay on DBS and peripheral leukocytes showed abnormal results in sixteen and six patients, respectively. Eight patients were tested for the mutation, seven of whom were negative and one patient showed a positive mutation analysis result. One female patient who presented with splenomegaly and thrombocytopenia was diagnosed with type 1 GD. The detection rate of GD was 0.2841% (exact 95% CI, 0.0072‒). Conclusion The detection rate of GD in probable high-risk patients in Korea was lower than expected.However, the role of hemato-oncologists is still important in the diagnosis of GD.

Background: This study aimed to determine factors affecting serum levels of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies 2 months after coronavirus disease 2019 (COVID-19) vaccination in young and middle aged healthy adults. Materials and Methods: Healthcare workers who have no history of SARS-CoV-2 infection, were enrolled at 2 months after second shot of BNT162b2 mRNA COVID-19 vaccine. Antibody immunoglobulin G against the spike protein subunit of SARS-CoV-2 was semi-quantitatively measured using 4 commercial enzyme-linked immunosorbent assay kits. Factors affecting anti-SARS-CoV-2 antibodies levels were investigated. Results: Fifty-one persons (22 - 54 years, male sex; 19.6%) were enrolled and all participants acquired anti-SARS-CoV-2 antibodies in four diagnostic kits. Anti-SARS-CoV-2 antibodies were strongly correlated between diagnostic kits; SG Medical and Genscript (r = 0.942), SG Medical and HB Healthcare (r = 0.903), and HB Healthcare and Genscript (r = 0.868). We investigated factors affecting antibody level using SG medical kit. The median inhibition was 93.1%, and 84.0% of participants showed >90.0% inhibition. Systemic adverse event severity had no association with the anti-SARS-CoV-2 antibodies level. Antibody level was inversely correlated with weight (-0.312, P = 0.027), body mass index (BMI) (r = -0.303, i>P = 0.032), and body surface area (r = -0.285, i>P = 0.044). In multivariate analysis, the upper 50% of antiSARS-CoV-2 antibodies (≥93.1%) was inversely associated with weight (odds ratio [OR]: 0.19; 95% confidence interval [CI]: 0.04 - 0.83 in weight ≥55kg) and BMI (OR: 0.12; 95% CI: 0.03 - 0.61 in BMI ≥22 kg/m2 ). Conclusion Anti-SARS-CoV-2 antibody was inversely correlated with weight and BMI, which may be used as a marker to predict immune response of BNT162b2 mRNA vaccination in young and middle aged adults.