Purpose: . This study evaluated the accuracy of implant impression techniques using scan healing abutments compared to conventional techniques. Materials and methods: . A mandibular model with implants at #34, 36, and 46 was used. Experiments were conducted for single implant and 3-unit bridge scenarios. Groups were as follows: Group IOS - Scan healing abutments were scanned with an intraoral scanner. Group Imp - Scan healing abutments were used, and impressions were taken with silicone material, followed by model scanning. Group Sb - Scan bodies were scanned with an intraoral scanner. Group Trans - Impressions were taken with transfer copings, and models were scanned. Each group was scanned 10 times, and deviations in central distance and angulation of analogs were measured. Statistical analyses were performed using ANOVA and post-hoc tests at a 95% confidence level. Results: . For single implants, there were no significant differences in distance deviation (P > .05). Angular deviation values were: IOS (0.24 ± 0.10°), Imp (0.19 ± 0.06°), Sb (0.38 ± 0.05°), and Trans (0.29 ± 0.06°), with Sb showing significantly larger values than IOS and Imp (P < .05). For bridges, distance deviation did not significantly differ (P > .05). Angular deviations were: IOS (0.21 ± 0.08°), Imp (0.21 ± 0.09°), Sb (0.25 ± 0.10°), and Trans (0.46 ± 0.19°), with Trans showing significantly larger values than the others (P < .05). Conclusion . Scan healing abutment techniques showed similar accuracy to traditional methods. They could be a viable alternative for single implant crowns or short-span fixed dental prostheses.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: Infliximab treatment failure in patients with inflammatory bowel disease may result from sub-optimal infliximab trough level. An understanding of pharmacokinetics (PKs) is important to maintain an optimal trough level. PK studies of the switch to subcutaneous (SC) infliximab from intravenous (IV) infliximab using real-world data are lacking. We aimed to develop a population PK model of IV and SC infliximab to predict individual infliximab exposure during maintenance therapy. Methods: We used data from prospectively collected data on IV and SC infliximab concentrations in patients with inflammatory bowel disease receiving maintenance treatment from February 2020 to December 2022 at Samsung Medical Center. Population PK analysis was conducted by using a two-compartment model with first-order absorption and first-order elimination. Goodness-of-fit plots and visual predictive check were used to evaluate the PK model. Results: A total of 2,132 samples from 181 patients (149 Crohn’s disease and 32 ulcerative colitis) were analyzed. We developed an infliximab population PK model using body mass index, albumin, C-reactive protein level, and the anti-drug antibody level and validated its predictive performance. Conclusions It may be possible to predict the infliximab trough level of both IV and SC infliximab in patients with inflammatory bowel disease during maintenance treatment by using our model in real-world practice.

Oxidative stress due to hyperglycemia damages the functions of retinal pigment epithelial (RPE) cells and is a major risk factor for diabetic retinopathy (DR). Paeoniflorin is a monoterpenoid glycoside found in the roots of Paeonia lactiflora Pall and has been reported to have a variety of health benefits. However, the mechanisms underlying its therapeutic effects on high glucose (HG)-induced oxidative damage in RPE cells are not fully understood. In this study, we investigated the protective effect of paeoniflorin against HG-induced oxidative damage in cultured human RPE ARPE-19 cells, an in vitro model of hyperglycemia. Pretreatment with paeoniflorin markedly reduced HG-induced cytotoxicity and DNA damage. Paeoniflorin inhibited HG-induced apoptosis by suppressing activation of the caspase cascade, and this suppression was associated with the blockade of cytochrome c release to cytoplasm by maintaining mitochondrial membrane stability. In addition, paeoniflorin suppressed the HG-induced production of reactive oxygen species (ROS), increased the phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), a key redox regulator, and the expression of its downstream factor heme oxygenase-1 (HO-1). On the other hand, zinc protoporphyrin (ZnPP), an inhibitor of HO-1, abolished the protective effect of paeoniflorin against ROS production in HG-treated cells. Furthermore, ZnPP reversed the protective effects of paeoniflorin against HG-induced cellular damage and induced mitochondrial damage, DNA injury, and apoptosis in paeoniflorin-treated cells. These results suggest that paeoniflorin protects RPE cells from HG-mediated oxidative stress-induced cytotoxicity by activating Nrf2/HO-1 signaling and highlight the potential therapeutic use of paeoniflorin to improve the symptoms of DR.

Purpose: There is few evidence regarding the optimal salvage treatment options for loco-reginal recurrence of esophageal cancer. This study aimed to evaluate the clinical outcomes of salvage radiotherapy (RT) in patients with loco-regional recurrence (LRR) after surgery for esophageal cancer. Materials and Methods: We retrospectively reviewed 147 esophageal cancer patients who received salvage RT for loco-regional recurrence between 1996 and December 2019. A total dose of 60 Gy in 20 fractions was used for RT alone and 60-70 Gy in 30-35 fractions for concurrent chemoradiotherapy (CCRT). Results: The patients’ median age was 65 years (range, 41 to 86 years). The median disease-free interval was 13.5 months (1.0 to 97.4 months). After a median 18.8 months follow-up, the 2-year overall survival (OS) and progression-free survival (PFS) rates were 38.1% and 25.9%, respectively. The median OS and PFS were 18.8 and 8.4 months, respectively. The CCRT could not improve OS compared to RT (p=0.336), but there was a trend of better PFS in the CCRT group. Regarding toxicities, the rate of grade 3 or higher toxicity was 10.9% occurring in 16 patients, and it was higher in patients who received CCRT than in the RT alone group (19.6% vs. 6.3%, p=0.023). Conclusion Salvage RT alone as well as CCRT could be effective in patients with locoregionally recurrent esophageal cancer.

Purpose: . This study evaluated the accuracy of implant impression techniques using scan healing abutments compared to conventional techniques. Materials and methods: . A mandibular model with implants at #34, 36, and 46 was used. Experiments were conducted for single implant and 3-unit bridge scenarios. Groups were as follows: Group IOS - Scan healing abutments were scanned with an intraoral scanner. Group Imp - Scan healing abutments were used, and impressions were taken with silicone material, followed by model scanning. Group Sb - Scan bodies were scanned with an intraoral scanner. Group Trans - Impressions were taken with transfer copings, and models were scanned. Each group was scanned 10 times, and deviations in central distance and angulation of analogs were measured. Statistical analyses were performed using ANOVA and post-hoc tests at a 95% confidence level. Results: . For single implants, there were no significant differences in distance deviation (P > .05). Angular deviation values were: IOS (0.24 ± 0.10°), Imp (0.19 ± 0.06°), Sb (0.38 ± 0.05°), and Trans (0.29 ± 0.06°), with Sb showing significantly larger values than IOS and Imp (P < .05). For bridges, distance deviation did not significantly differ (P > .05). Angular deviations were: IOS (0.21 ± 0.08°), Imp (0.21 ± 0.09°), Sb (0.25 ± 0.10°), and Trans (0.46 ± 0.19°), with Trans showing significantly larger values than the others (P < .05). Conclusion . Scan healing abutment techniques showed similar accuracy to traditional methods. They could be a viable alternative for single implant crowns or short-span fixed dental prostheses.

Purpose: . This study evaluated the accuracy of implant impression techniques using scan healing abutments compared to conventional techniques. Materials and methods: . A mandibular model with implants at #34, 36, and 46 was used. Experiments were conducted for single implant and 3-unit bridge scenarios. Groups were as follows: Group IOS - Scan healing abutments were scanned with an intraoral scanner. Group Imp - Scan healing abutments were used, and impressions were taken with silicone material, followed by model scanning. Group Sb - Scan bodies were scanned with an intraoral scanner. Group Trans - Impressions were taken with transfer copings, and models were scanned. Each group was scanned 10 times, and deviations in central distance and angulation of analogs were measured. Statistical analyses were performed using ANOVA and post-hoc tests at a 95% confidence level. Results: . For single implants, there were no significant differences in distance deviation (P > .05). Angular deviation values were: IOS (0.24 ± 0.10°), Imp (0.19 ± 0.06°), Sb (0.38 ± 0.05°), and Trans (0.29 ± 0.06°), with Sb showing significantly larger values than IOS and Imp (P < .05). For bridges, distance deviation did not significantly differ (P > .05). Angular deviations were: IOS (0.21 ± 0.08°), Imp (0.21 ± 0.09°), Sb (0.25 ± 0.10°), and Trans (0.46 ± 0.19°), with Trans showing significantly larger values than the others (P < .05). Conclusion . Scan healing abutment techniques showed similar accuracy to traditional methods. They could be a viable alternative for single implant crowns or short-span fixed dental prostheses.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: Infliximab treatment failure in patients with inflammatory bowel disease may result from sub-optimal infliximab trough level. An understanding of pharmacokinetics (PKs) is important to maintain an optimal trough level. PK studies of the switch to subcutaneous (SC) infliximab from intravenous (IV) infliximab using real-world data are lacking. We aimed to develop a population PK model of IV and SC infliximab to predict individual infliximab exposure during maintenance therapy. Methods: We used data from prospectively collected data on IV and SC infliximab concentrations in patients with inflammatory bowel disease receiving maintenance treatment from February 2020 to December 2022 at Samsung Medical Center. Population PK analysis was conducted by using a two-compartment model with first-order absorption and first-order elimination. Goodness-of-fit plots and visual predictive check were used to evaluate the PK model. Results: A total of 2,132 samples from 181 patients (149 Crohn’s disease and 32 ulcerative colitis) were analyzed. We developed an infliximab population PK model using body mass index, albumin, C-reactive protein level, and the anti-drug antibody level and validated its predictive performance. Conclusions It may be possible to predict the infliximab trough level of both IV and SC infliximab in patients with inflammatory bowel disease during maintenance treatment by using our model in real-world practice.

Oxidative stress due to hyperglycemia damages the functions of retinal pigment epithelial (RPE) cells and is a major risk factor for diabetic retinopathy (DR). Paeoniflorin is a monoterpenoid glycoside found in the roots of Paeonia lactiflora Pall and has been reported to have a variety of health benefits. However, the mechanisms underlying its therapeutic effects on high glucose (HG)-induced oxidative damage in RPE cells are not fully understood. In this study, we investigated the protective effect of paeoniflorin against HG-induced oxidative damage in cultured human RPE ARPE-19 cells, an in vitro model of hyperglycemia. Pretreatment with paeoniflorin markedly reduced HG-induced cytotoxicity and DNA damage. Paeoniflorin inhibited HG-induced apoptosis by suppressing activation of the caspase cascade, and this suppression was associated with the blockade of cytochrome c release to cytoplasm by maintaining mitochondrial membrane stability. In addition, paeoniflorin suppressed the HG-induced production of reactive oxygen species (ROS), increased the phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), a key redox regulator, and the expression of its downstream factor heme oxygenase-1 (HO-1). On the other hand, zinc protoporphyrin (ZnPP), an inhibitor of HO-1, abolished the protective effect of paeoniflorin against ROS production in HG-treated cells. Furthermore, ZnPP reversed the protective effects of paeoniflorin against HG-induced cellular damage and induced mitochondrial damage, DNA injury, and apoptosis in paeoniflorin-treated cells. These results suggest that paeoniflorin protects RPE cells from HG-mediated oxidative stress-induced cytotoxicity by activating Nrf2/HO-1 signaling and highlight the potential therapeutic use of paeoniflorin to improve the symptoms of DR.