Background/Aims: Besifovir dipivoxil maleate (BSV) and tenofovir alafenamide fumarate (TAF) have been recently approved in Korea as the initial antiviral agents for chronic hepatitis B (CHB).However, the real-world outcome data for these drugs remain limited. Therefore, we conducted a noninferiority analysis using real-world data to compare the clinical outcomes of the two nucleotide analogs in treatment-naïve patients with CHB. Methods: We retrospectively investigated a cohort of patients with CHB who received BSV or TAF as first-line antiviral agents. The endpoints were virological response (VR) and liver-related clinical outcomes. Results: A total of 537 patients, consisting of 202 and 335 patients administered BSV and TAF, respectively, were followed up for 42 months. No significant difference was observed between the VRs of the patients from the two groups. The rates of biochemical response, virologic breakthrough, and incidence rates of hepatocellular carcinoma did not differ between the groups. However, the hepatitis B e antigen seroclearance rate was higher and the renal function declined less in the BSV group. Multivariable analysis indicated older age, alcohol abuse, cirrhosis and ascites, and lower serum HBV DNA level to be independently associated with increased hepatocellular carcinoma risk. The 1:1 propensity score-matched analysis with 400 patients showed VR rates of 85.0% and 88.7% in the BSV and TAF group patients, respectively, at 2 years. The absolute value of the 95% confidence interval for the difference (–0.04 to 0.12) satisfied the a priori limit of a noninferiority of 0.15. Conclusions BSV is noninferior to TAF in terms of VR, and their clinical outcomes are comparable to CHB.

Osteoarthritis (OA) involves cartilage degeneration, thereby causing inflammation and pain. Cardiovascular diseases, such as dyslipidemia, are risk factors for OA; however, the mechanism is unclear. We investigated the effect of dyslipidemia on the development of OA. Treatment of cartilage cells with low-density lipoprotein (LDL) enhanced abnormal autophagy but suppressed normal autophagy and reduced the activity of transcription factor EB (TFEB), which is important for the function of lysosomes. Treatment of LDL-exposed chondrocytes with rapamycin, which activates TFEB, restored normal autophagy. Also, LDL enhanced the inflammatory death of chondrocytes, an effect reversed by rapamycin. In an animal model of hyperlipidemia-associated OA, dyslipidemia accelerated the development of OA, an effect reversed by treatment with a statin, an anti-dyslipidemia drug, or rapamycin, which activates TFEB. Dyslipidemia reduced the autophagic flux and induced necroptosis in the cartilage tissue of patients with OA. The levels of triglycerides, LDL, and total cholesterol were increased in patients with OA compared to those without OA. The C-reactive protein level of patients with dyslipidemia was higher than that of those without dyslipidemia after total knee replacement arthroplasty. In conclusion, oxidized LDL, an important risk factor of dyslipidemia, inhibited the activity of TFEB and reduced the autophagic flux, thereby inducing necroptosis in chondrocytes.

After tooth extraction, alveolar bone is resorbed over time. Loss of alveolar bone and reduction of upper soft tissue poses difficulties in future implant placement and long-term survival of the implant. This case report focuses on increasing the soft and hard tissues at the implant placement site by using alveolar ridge augmentation and a xenogeneic collagen matrix as a soft tissue substitute in an extraction socket affected by periodontal disease. In each case, the width of the alveolar bone increased to 6 mm, 8 mm, and 4 mm, and regeneration of the interdental papilla around the implant was shown, as well as buccal keratinized gingiva of 4 mm, 6 mm, and 4 mm, respectively. Enlarged alveolar bone facilitates implant surgery, and interdental papillae and keratinized gingiva enable aes-thetic prosthesis. This study performed alveolar ridge augmentation on patients with extraction sockets affected by periodontal dis-ease and additionally used soft tissue substitutes to provide a better environment for implant placement and have positive effects for aesthetic and predictive implant surgery.

Background/Aims: Efficient anti-fibrotic therapies are required for the treatment of liver cirrhosis. Hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) and cyclooxygenase-2 (COX-2) inhibitors have been reported to have anti-fibrotic effects. Here, we investigated whether combined treatment with a statin and a COX-2 inhibitor has synergistic anti-fibrotic effects. Methods: The effects of treatment strategies incorporating both simvastatin and a COX-2 inhibitor, NS-398, were investigated using an immortalized human hepatic stellate cell line (LX-2) and a hepatic fibrosis mouse model developed using thioacetamide (TAA) in drinking water. Cellular proliferation was investigated via 5-bromo-2-deoxyuridine uptake. Pro- and anti-apoptotic factors were investigated through Western blotting and real-time polymerase chain reaction analysis. Results: The evaluation of the anti-proliferative effects on LX-2 cells showed that the observed effects were more pronounced with combination therapy than with single-drug therapy. Moreover, hepatic fibrosis and collagen deposition decreased significantly in TAA-treated mice in response to the combined treatment strategy. The mechanisms underlying the anti-fibrotic effects of the combination therapy were investigated. The effects of the combination therapy were correlated with increased expression levels of extracellular signal-regulated kinase 1/2 signaling molecules, upregulation of the Bax/Bcl-2 signaling pathway, inhibition of the transforming growth factor-β signaling pathway, and inhibition of tissue inhibitor of matrix metalloproteinases 1 and 2. Conclusions The combination of simvastatin and NS-398 resulted in a synergistic anti-fibrotic effect through multiple pathways. These findings offer a theoretical insight into the possible clinical application of this strategy for the treatment of advanced liver diseases with hepatic fibrosis.

Background/Aims: Sorafenib is the first approved systemic treatment for advanced hepatocellular carcinoma (HCC). However, its clinical utility is limited, especially in Asian countries. Several reports have suggested the survival benefits of hepatic arterial infusion chemotherapy (HAIC) for advanced HCC with main portal vein tumor thrombosis (PVTT). This study aimed to compare the efficacy of sorafenib-based therapy with that of HAIC-based therapy for advanced HCC with main PVTT. Methods: Advanced HCC patients with main PVTT treated with sorafenib or HAIC between 2008 and 2016 at Korea University Medical Center were included. We evaluated overall survival (OS), time-to-progression (TTP), and the disease control rate (DCR). Results: Seventy-three patients were treated with sorafenib (n=35) or HAIC (n=38). Baseline characteristics were not significantly different between groups, except the presence of solid organ metastasis (46% vs 5.3%, p<0.001). The median OS time was not significantly different between the groups (6.4 months vs 10.0 months, p=0.139). TTP was longer in the HAIC group than in the sorafenib group (2.1 months vs 6.2 months, p=0.006). The DCR was also better in the HAIC group than in the sorafenib group (37% vs 76%, p=0.001). Subgroup analysis, which excluded patients with extrahepatic solid organ metastasis, showed the same trends for the median OS time (8.8 months vs 11.1 months, p=0.097), TTP (1.9 months vs 6.0 months, p<0.001), and DCR (53% vs 81%, p=0.030). Conclusions HAIC-based therapy may be an alternative to sorafenib for advanced HCC with main PVTT by providing longer TTP and a better DCR.

Background/Aims: Besifovir dipivoxil maleate (BSV), an acyclic nucleotide phosphonate, shows potent antiviral activity against hepatitis B virus. Our previous 48-week trial revealed that BSV has comparable antiviral efficacy to tenofovir disoproxil fumarate (TDF) and better safety profiles in terms of improved renal and bone safety. This extension study evaluated the prolonged efficacy and safety of BSV in treatment-naive chronic hepatitis B patients. Methods: Patients continued to participate in an open-label BSV study after an initial 48-week double-blind comparison of BSV and TDF treatment. The antiviral efficacy and drug safety was evaluated up to 192 weeks in two groups: patients continuing BSV treatment (BSV-BSV) and patients switching from TDF to BSV after 48 weeks (TDF-BSV). Results: Among 197 patients receiving randomized treatments, 170 (86%) entered the open-label phase and 152 (77%) entered the 192-week extension study. Virological response rates over 192 weeks were 92.50% and 93.06% in the BSV-BSV and TDF-BSV groups, respectively (P=0.90). Hepatitis B envelop antigen seroconversion and alanine aminotransferase normalization rates were similar between the groups (P=0.75 and P=0.36, respectively). There were no drug-resistant mutations to BSV. Bone mineral density and renal function were well preserved in the BSV-BSV group, whereas these initially worsened then recovered after switching therapy in the TDF-BSV group. Conclusions BSV maintained potent antiviral efficacy after 192 weeks and showed no evidence of drug resistance. BSV was safe, well tolerated, and effective in patients who switched from TDF to BSV. Trial Registration Number: NCT01937806 (date: 10 Sep 2013).

Background/Aims: Irreversible electroporation (IRE) is a relatively new ablation method. However, the application of IRE ablation in the treatment of biliary disease has not been attempted. A minimally invasive approach using endoscopic retrograde cholangiopancreatography (ERCP) can be a novel therapeutic modality for IRE ablation. In this study, we aimed to investigate the feasibility of endoscopic IRE for the biliary tract using an animal model. Methods: A new catheter-type electrode was developed for endoscopic IRE ablation of the biliary tract. We performed ERCP and endoscopic IRE ablations in the normal common bile duct of Yorkshire pigs. The experimental setting of IRE was 500 V/cm (50 pulses, 100-µs length). The animals were sacrificed after 24 hr, and the ablated bile duct was examined. Results: Well-demarcated focal color changes were observed on the mucosa of the common bile duct. The depth of change after IRE was confined to the mucosal and submucosal layers. Apoptotic changes in the bile duct were observed only around the IRE ablation area. Immunohistochemistry assay showed cell death in the bile duct along the electrode. Conclusions Endoscopic IRE ablation using ERCP was successfully performed in the common bile duct. It can be a potential option for the treatment of biliary tumors.

Background/Aims: Several attempts have been made to incorporate smart glasses in the medical field. We applied wearable display glasses to show the position of an observer during endoscopy and compared students’ responses between the conventional and new methods. Methods: We surveyed 28 medical students regarding the use of wearable display devices. The students used wearable display glasses to observe an endoscopic procedure and answered the prepared questionnaire. Their collected responses were analyzed for statistical correlations between each variable. Results: The survey of medical students revealed disadvantages including dizziness (dissatisfied and very dissatisfied: 21.5%) and eye fatigue (25% dissatisfied) and advantages including concentration (satisfied and very satisfied: 57.2%) and securing patient rights (71.4%). The students showed more positive than negative reviews regarding the new devices (32.1% vs. 21.5%). Conclusions We investigated the advantages and disadvantages of viewing the endoscope image with new wearable display glasses compared to the conventional method using the survey to record user experience. The results revealed relatively positive responses from the medical students in the survey. If the new device compensates for some shortcomings, its use in the endoscopy room will be feasible.

Background/Aims: Most prognostic prediction models for patients with liver cirrhosis include serum total bilirubin (TB) level as a component. This study investigated prognostic performance of serum direct bilirubin (DB) and developed new DB level-based prediction models for cirrhosis. Methods: A total of 983 hospitalized patients with liver cirrhosis were included. DB-Model for End-Stage Liver Disease (MELD) score was calculated using MELD score formula, with serum DB level replacing TB level. Results: Mean age of study population was 56.1 years. Alcoholic liver disease was the most frequent underlying condition (471 patients, 47.9%). Within 6 months, 144 patients (14.6%) died or received liver transplantation due to severe liver dysfunction. The area under the receiver operating characteristic curve (AUROC) for prediction of 6-month mortality with DB level was significantly higher than that with TB level (p<0.001). The AUROC of DB-MELD score for prediction of 6-month mortality was significantly higher than that of MELD score (p<0.001). Patients were randomly divided into training (n=492) and validation (n=491) cohorts. A new prognostic prediction model, “Direct Bilirubin, INR, and Creatinine” (DiBIC) score, was developed based on the most significant predictors of 6-month mortality. In training set, AUROC of DiBIC score for prediction of 6-month mortality was 0.892, which was significantly higher than that of the MELD score (0.875, p=0.017), but not different from that of DB-MELD score (0.886, p=0.272). Similar results were observed in validation set. Conclusions New prognostic models, DB-MELD and DiBIC scores, have good prognostic performance in liver cirrhosis patients, outperforming other currently available models.

Background/Aims: We investigated changes in recurrence rates and significant recurrence predictors over time after complete cure of hepatocellular carcinoma (HCC). Methods: A total of 1,491 patients with first-time diagnosis of Barcelona Clinic Liver Cancer stage A HCC, completely cured by treatment between 2007 and 2016, were recruited from two Korean tertiary institutes. Results: The mean age of the population (1,144 men and 347 women) was 58.6 years. Of the total population, 914 patients (61.3%) had liver cirrhosis. Nine-hundred and forty-one (63.1%) and 550 (36.9%) patients were treated with surgical resection and radiofrequency ablation (RFA), respectively. One-year cumulative incidences of HCC recurrence were 14.3%, 9.9%, and 5.1% from the time of treatment, 3 years after treatment, and 5 years after treatment, respectively. Upon multivariate analysis, multiple tumors, maximal tumor size ≥3 cm, and high Model for End-Stage Liver Disease scores were independently associated with increased HCC recurrence risk from the time of treatment and 1 and 2 years after curative treatment (all p<0.05, except for maxi-mal tumor size ≥3 cm for recurrence 2 years after treatment). Meanwhile, liver cirrhosis and RFA were independently associated with the increased HCC recurrence risk for almost all time points (liver cirrhosis: all p<0.05; RFA: all p<0.005 except for recurrence from 5 years after treatment). Conclusions The recurrence rate of HCC after curative treatment gradually decreased over time. Two years after treatment, when tumor-related factors lose their prognostic implications, may be used as a cutoff to define the boundary between early and late recurrence of HCC.