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Research involving a Force-Balanced Coil (FBC), which is a helically wound toroidal coil, is described and discussed.

A small helical coil was designed and fabricated using 340 m of Ag-sheathed Bi-2223 high-temperature superconductive (HTS) tapes. The purpose was to estimate helically winding problems involving a Force-Balanced Coil.

A Stress-Balanced Coil is proposed for application to superconducting magnetic energy storage systems with large aspect ratio coil.

Objectives: This systematic review and meta-analysis aimed to evaluate the diagnostic ability and examine the efficacy of countermeasures to adverse events of mucosal incision-assisted biopsy (MIAB) for gastric subepithelial tumors (SETs)., Methods: We performed a literature search and identified 533 relevant articles. Eleven articles, including 339 lesions, were ultimately used in the meta-analysis. The primary end-point was the pathological diagnostic rate of MIAB for gastric SETs, and the secondary end-point was the incidence of adverse events. The efficacy of acid secretion inhibitors in preventing postoperative bleeding and that of local injection before incision to prevent perforation were also examined., Results: Nine studies were conducted in Japan and two in South Korea, of which only two were prospective studies. The pooled pathological diagnostic rate of MIAB for gastric SETs was 87.8% (95% confidence interval [CI] 80.2-94.0; I 2  = 68.7%). The adverse event rate of the pooled population was 0.2% (95% CI 0-1.4; I 2  = 0%). The acid secretion inhibitors significantly reduced postoperative bleeding (odds ratio 0.06, 95% CI 0.01-0.66, P = 0.02). Perforation occurred in 0% and 2.6% of the local and nonlocal injection cohorts, respectively, and the pathological diagnostic rates were 50% and 66.7%, respectively., Conclusions: MIAB is a reliable technique with a favorable diagnostic rate and few adverse events. Acid secretion inhibitors may effectively prevent postoperative bleeding; however, the efficacy of local injection remains unclear. This technique could be an option for tissue sampling in gastric SETs., (© 2024 Japan Gastroenterological Endoscopy Society.)

Competing Interests: Osamu Goto is tied with Olympus as a paid speaker, and has a history of complimentary use of the flexible needle holder and scissor forceps for research purposes for the said company. Naohiko Akimoto, Yumiko Ishikawa, Eriko Koizumi, Kazutoshi Higuchi, Jun Omori, and Katsuhiko Iwakiri have no COI.

Aims: During intraoperative bleeding in endoscopic submucosal dissection (ESD), switching to spray coagulation may be beneficial compared with the continuous use of swift coagulation and can reduce the need for hemostatic forceps. We retrospectively assessed the effectiveness of spray modes on intraoperative bleeding during gastric ESD., Methods and Results: A total of 316 bleeding events (156 in the Swift group and 160 in the Spray group) were consecutively recorded. In the Swift group, hemostasis was performed using the swift mode with a retracted tip of the needle-type knife, followed by the hemostatic forceps. In the Spray group, bleeding was treated in a stepwise manner: the swift mode, the spray mode, and the hemostatic forceps. All bleeding events were assigned to one of two groups by an endoscopist who retrospectively reviewed the videos. We compared the use of hemostatic forceps, the total hemostatic time, and the cumulative hemostasis rate between the two groups.The use of hemostatic forceps was significantly lower in the Spray group than in the Swift group (32.7% vs. 13.8%, P  < 0.001). There was no significant difference in the total hemostatic time (Swift group, 20 s.; Spray group, 16 s.; P  = 0.42), whereas the cumulative hemostasis rate with the knife was significantly higher in the Spray group ( P  = 0.007)., Conclusion: The results suggested that spray coagulation from the tip of the needle-type knife could reduce the use of hemostatic forceps. In gastric ESD, spray coagulation may facilitate the hemostasis of intraoperative bleeding., (© 2024 The Author(s). JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Endoscopic hand suturing (EHS) was first developed to firmly close a mucosal defect following endoscopic submucosal dissection and has the potential for expanded applications. This study aimed to investigate the feasibility and safety of EHS in various clinical settings. In this single-center pilot study, 15 patients who had diseases with potential indications for EHS were prospectively recruited. Technical success, clinical success after the procedure, and severe EHS-related adverse events (AEs) were evaluated. EHS was applied for defect closure after gastric subepithelial lesion removal under laparoscopic observation (n = 9), defect closure after rectal endoscopic full-thickness resection (EFTR) (n = 2), defect closure after thoracoscopy-assisted esophageal EFTR (n = 1), mucosal closure for gastric ulcer bleeding (n = 1), mucosal closure after peroral endoscopic myotomy (POEM) (n = 1), and postoperative anastomotic leak (n = 1). EHS was completed without severe AEs and the clinical courses were also favorable in 13 patients (87%). The median suturing time was 61 minutes. In patients with POEM and anastomotic leak, EHS was discontinued because of the narrow lumen. In conclusion, EHS appears feasible and safe in situations., Competing Interests: Conflict of Interest The flexible needle holder and the scissors forceps which were used in this study were complimentarily provided by Olympus Co., Ltd. Dr. Osamu Goto has ties with Olympus Co. Ltd. as a consultant and a paid speaker. The remaining authors have no conflict of interest to declare., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Background: Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection (ESD); however, the preoperative evaluation of tumor size is often different from histological assessment. Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD., Aim: To investigate the tumor size discrepancy between endoscopic and pathological evaluations and the influencing factors., Methods: This was a retrospective study conducted at a single institution. A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected. We first assessed the difference in size with an absolute percentage of the scaling discrepancy. Subsequently, we compared the clinicopathological characteristics of the correct scaling group (> -33% and < 33%) with that of the incorrect scaling group (< -33% or > 33%), which was further subdivided into the underscaling group (-33% or less of the discrepancy) and overscaling group (33% or more of the discrepancy), respectively. As secondary outcome measures, parameters on size estimation were compared between the underscaling and correct scaling groups, as well as between the overscaling and correct scaling groups. Finally, multivariate analysis was performed in terms of the following relevant parameters on size estimation: Pathological size, location, and possible influential factors ( P < 0.1) in the univariate analysis., Results: The mean of absolute percentage in the scaling discordance was 21%, and 91 lesions were considered to be incorrectly estimated in size. The incorrect scaling was significantly remarkable in larger lesions (40 mm vs 28 mm; P < 0.001) and less experience ( P < 0.001), and these two factors were influential on the underscaling (75 lesions; P < 0.001). Conversely, compared with the correct scaling group, 16 lesions in the overscaling group were significantly small (20 mm vs 28 mm; P < 0.001), and the small lesion size was influential on the overscaling ( P = 0.002)., Conclusion: Lesions indicated for colorectal ESD tended to be underestimated in large tumors, but overestimated in small ones. This discrepancy appears worth understanding for optimal procedural preparation., Competing Interests: Conflict-of-interest statement: The authors have no conflicts of interest to declare., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background and Aims: An increasing number of patients are undergoing gastric endoscopic submucosal dissection (ESD) with active prescriptions of direct oral anticoagulants (DOACs). Only a few reports have described the effects of DOAC intake on postoperative bleeding. We aimed to investigate the bleeding risk associated with DOACs after gastric ESD., Methods: Clinical studies published up to April 2022 showing bleeding rates after gastric ESD in patients taking DOACs were identified using electronic searches. The primary outcome was the rate of bleeding after gastric ESD in patients receiving DOACs compared to those not receiving antithrombotic therapy. In this meta-analysis, odds ratios (ORs) were calculated and pooled using a random effects model. The secondary outcome was the difference in the bleeding rate between patients treated with DOACs and those treated with warfarin and antiplatelet drugs., Results: Seven studies were included in this meta-analysis. The pooled analysis showed that DOACs had a higher bleeding rate than non-thrombotic therapy (17.0% vs. 3.4%; OR 5.72; 95% confidence interval [CI], 4.33-7.54; I 2  = 0%). The bleeding risk associated with DOAC administration was similar to that associated with warfarin (17.0% vs. 20.0%; OR 0.83; 95% CI 0.59-1.18; I 2  = 0%), whereas it was higher than that associated with antiplatelet administration (16.9% vs. 11.0%; OR 1.63; 95% CI 1.14-2.34; I 2  = 8%)., Conclusions: This meta-analysis reveals that the bleeding risk of DOACs is higher than that of non-antithrombotics and antiplatelets, whereas it is comparable to that of warfarin. Gastric ESD in patients on anticoagulants requires careful postoperative management., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Subclinical stricture after esophageal endoscopic submucosal dissection (ESD) makes the detection and re-ESD of metachronous lesions difficult. This study aimed to investigate the effectiveness of prophylactic steroid use after esophageal ESD for mucosal defects with a circumference less than 75% for the prevention of symptomatic and asymptomatic stricture., Methods: In 80 retrospectively enrolled patients, we collected paired endoscopic images of a mucosal defects immediately after resection and a scar thereafter. After calculating circumference by image analysis software, all patients were classified into three groups in reference to mucosal defect circumference (MDC; ≤ 50%, 50-75%, ≥ 75%). Frequency of steroid use and symptomatic stricture were compared, and in < 75% MDC patients, a degree of asymptomatic stricture with or without steroid was compared by calculating a scar contraction rate (SCR)., Results: In the ≤ 50% (43 patients), 50-75% (27 patients) and ≥ 75% (10 patients) MDC groups, steroids were used in 12%, 59% and 100%, respectively, and symptomatic stricture occurred in 0%, 7% and 40%, respectively. In < 75% MDC patients, SCR in the steroid cohort was significantly lower than that in the nonsteroid cohort (42% vs. 65%, p = 0.002). No steroid-related adverse events occurred., Conclusion: Steroid use even for mucosal defects with < 75% circumference appears effective for the reduction of the risk on both symptomatic and asymptomatic stricture after esophageal ESD., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: Mucosal incision-assisted biopsy (MIAB) has been introduced as an alternative to endoscopic ultrasound-guided fine needle aspiration for tissue sampling of subepithelial lesions. However, there have been few reports on MIAB, and the evidence is lacking, particularly in small lesions. In this case series, we investigated the technical outcomes and postprocedural influences of MIAB for gastric subepithelial lesions 10 mm or greater in size., Methods: We retrospectively reviewed cases with the intraluminal growth type of possible gastrointestinal stromal tumors, in which MIAB was performed at a single institution between October 2020 and August 2022. Technical success, adverse events, and clinical courses following the procedure were evaluated., Results: In 48 MIAB cases with a median tumor diameter of 16 mm, the success rate of tissue sampling and the diagnostic rate were 96% and 92%, respectively. Two biopsies were considered sufficient for making the definitive diagnosis. Postoperative bleeding occurred in one case (2%). In 24 cases, surgery has performed a median of two months after MIAB, and no unfavorable findings caused by MIAB were seen intraoperatively. Finally, 23 cases were histologically diagnosed as gastrointestinal stromal tumors, and no patients who underwent MIAB experienced recurrence or metastasis during a median observation period of 13 months., Conclusions: The data indicated that MIAB appears feasible, safe, and useful for histological diagnosis of gastric intraluminal growth types of possible gastrointestinal stromal tumors, even those of a small size. Postprocedural clinical effects were considered negligible., Competing Interests: None., (© 2023 The Authors. DEN Open published by John Wiley & Sons Australia, Ltd on behalf of Japan Gastroenterological Endoscopy Society.)

Golden cyst nematodes have threatened the cultivation of 'Toyoshiro', a major potato variety used for chip processing in Japan. Common scab is a soilborne disease that occurs in potato fields worldwide. To solve these problems, we crossed two US varieties and selected a clone that showed a slightly higher marketable yield and a significantly higher yield rate, compared with 'Toyoshiro', and had good chip processing quality, extreme resistance to cyst nematodes, and moderately high resistance to common scab. This clone was named 'Poroshiri'; it is the first variety released from the Calbee Potato breeding program., (Copyright © 2023 by JAPANESE SOCIETY OF BREEDING.)

Introduction: Endoscopic suturing of a mucosal defect is expected to prevent postoperative bleeding after endoscopic submucosal dissection (ESD). Endoscopic suturing causes mucosal deformity, which may interfere with endoscopic surveillance thereafter. We retrospectively investigated long-term chronological changes in mucosal suturing by endoscopic suturing., Methods: Forty-three patients who underwent endoscopic hand suturing (EHS) after gastric ESD at three institutions were enrolled. First, our hypothesis that the suturing sites healed via inflammation, disappearance of mucosal inversion, and flattening was validated. Subsequently, the duration required to reach each healing step was evaluated., Results: A total of 137 follow-up endoscopies were assessed, in which all cases showed the hypothesized chronological course on the suturing sites. The 95th percentiles of the duration when showing the disappearance of the inflammatory change and the inverted change were 63 days and 15.5 months after the procedure, respectively., Discussion/conclusion: The data show that the mucosal deformity induced by EHS disappeared within 16 months. Endoscopic suturing is thus considered to have a negligible effect on endoscopic surveillance following the procedure., (© 2022 S. Karger AG, Basel.)

Competing Interests: The flexible needle holder and the scissor forceps that were used for the endoscopic hand suturing were provided complimentarily by Olympus Co., Ltd.

Background: The risk of bleeding after gastric endoscopic submucosal dissection (ESD) in antithrombotic agent users has increased, and its management remains a problem. Second-look endoscopy (SLE) following gastric ESD in antithrombotic agent users may be effective in preventing delayed bleeding, but this requires elucidation. Therefore, this study aimed to investigate the efficacy of SLE in reducing bleeding after gastric ESD in patients receiving antithrombotic agents., Methods: This retrospective cohort study was conducted at 19 referral hospitals in Japan. A total of 1,245 patients who were receiving antithrombotic agents underwent gastric ESD between January 2013 and July 2018. The incidence of delayed bleeding was compared between SLE and non-SLE groups using propensity score matching analysis., Results: Overall, 858 patients (SLE group, 657 patients; non-SLE group, 201 patients) were analyzed. After matching, 198 pairs were created. Delayed bleeding occurred in 10 patients (5.1%) in the SLE group and 16 patients (8.1%) in the non-SLE group [odds ratio (OR) 0.605, 95% confidence interval (CI) 0.23-1.46, p = 0.310]. In the subgroup analysis, SLE reduced the incidence of delayed bleeding in patients receiving heparin bridging therapy (6.3% and 40.0%, respectively; p = 0.004). In the SLE group, prophylactic coagulation did not significantly reduce delayed bleeding compared to the no treatment group (14.6% and 8.6%, respectively; p = 0.140)., Conclusions: SLE was ineffective in reducing bleeding after gastric ESD in antithrombotic agent users, overall. A prospective comparative study is warranted to definitively evaluate the effectiveness of SLE in reducing bleeding in high-risk patients., (© 2022. The Author(s) under exclusive licence to The International Gastric Cancer Association and The Japanese Gastric Cancer Association.)

Background: Endocytoscopy (ECS) aids early gastric cancer (EGC) diagnosis by visualization of cells. However, it is difficult for non-experts to accurately diagnose EGC using ECS. In this study, we developed and evaluated a convolutional neural network (CNN)-based system for ECS-aided EGC diagnosis., Methods: We constructed a CNN based on a residual neural network with a training dataset comprising 906 images from 61 EGC cases and 717 images from 65 noncancerous gastric mucosa (NGM) cases. To evaluate diagnostic ability, we used an independent test dataset comprising 313 images from 39 EGC cases and 235 images from 33 NGM cases. The test dataset was further evaluated by three endoscopists, and their findings were compared with CNN-based results., Results: The trained CNN required 7.0 s to analyze the test dataset. The area under the curve of the total ECS images was 0.93. The CNN produced 18 false positives from 7 NGM lesions and 74 false negatives from 28 EGC lesions. In the per-image analysis, the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 83.2%, 76.4%, 92.3%, 93.0%, and 74.6%, respectively, with the CNN and 76.8%, 73.4%, 81.3%, 83.9%, and 69.6%, respectively, for the endoscopist-derived values. The CNN-based findings had significantly higher specificity than the findings determined by all endoscopists. In the per-lesion analysis, the accuracy, sensitivity, specificity, PPV, and NPV of the CNN-based findings were 86.1%, 82.1%, 90.9%, 91.4%, and 81.1%, respectively, and those of the results calculated by the endoscopists were 82.4%, 79.5%, 85.9%, 86.9%, and 78.0%, respectively., Conclusions: Compared with three endoscopists, our CNN for ECS demonstrated higher specificity for EGC diagnosis. Using the CNN in ECS-based EGC diagnosis may improve the diagnostic performance of endoscopists., (© 2022. The Author(s).)

Background: It is unclear whether prophylactic endoscopic closure after colorectal endoscopic submucosal dissection (ESD) reduces the risk of postoperative adverse events due to variability in lesion characteristics. Therefore, we conducted a retrospective study using propensity score matching to evaluate the efficacy of prophylactic clip closure in preventing postoperative adverse events after colorectal ESD., Methods: This single-center retrospective cohort study included 219 colorectal neoplasms which were removed by ESD. The patients were allocated into the closure and non-closure groups, which were compared before and after propensity-score matching. Post-ESD adverse events including major and minor bleeding and delayed perforation were compared between the two groups., Results: In this present study, 97 and 122 lesions were allocated to the closure and non-closure groups, respectively, and propensity score matching created 61 matched pairs. The rate of adverse events was significantly lower in the closure group than in the non-closure group (8% vs. 28%, P = 0.008). Delayed perforation occurred in two patients in the non-closure group, whereas no patient in the closure group developed delayed perforation. In contrast, there were no significant differences in other postoperative events including the rate of abdominal pain; fever, white blood cell count, and C-reactive protein; and appetite loss between the two groups., Conclusions: Propensity score matching analysis demonstrated that prophylactic closure was associated with a significantly reduced rate of adverse events after colorectal ESD. When technically feasible, mucosal defect closure after colorectal ESD may result in a favorable postoperative course., (© 2022. The Author(s).)

Bleeding after gastric endoscopic submucosal dissection (ESD) remains problematic, especially in patients receiving antithrombotic therapy. Therefore, this study aimed to identify the risk factors. In this retrospective study, patients ( n  = 1,207) who underwent gastric ESD while receiving antithrombotic therapy were enrolled at Osaka Medical and Pharmaceutical University Hospital and 18 other referral hospitals in Japan. Risks of post-ESD bleeding were calculated using multivariable logistic regression. The dataset was divided into a derivation cohort and a validation cohort. We created a prediction model using the derivation cohort. The accuracy of the model was evaluated using the validation cohort. Post-ESD bleeding occurred in 142 (11.8%) participants. Multivariable analysis yielded an odds ratio of 2.33 for aspirin, 4.90 for P2Y12 receptor antagonist, 1.79 for cilostazol, 0.95 for other antithrombotic agents, 6.53 for warfarin, 5.65 for dabigatran, 7.84 for apixaban, 10.45 for edoxaban, 6.02 for rivaroxaban, and 1.46 for heparin bridging. The created prediction model was called safe ESD management using the risk analysis of post-bleeding in patients with antithrombotic therapy (SAMURAI). This model had good predictability, with a C-statistic of 0.77. In conclusion, use of the SAMURAI model will allow proactive management of post-ESD bleeding risk in patients receiving antithrombotic therapy., Competing Interests: No potential conflicts of interest were disclosed., (Copyright © 2022 JCBN.)

Background and Aims: Surgery is recommended in early gastric cancer (EGC) after noncurative endoscopic submucosal dissection (ESD), although observation can be an alternative. We aimed to develop a tailor-made treatment strategy for noncurative EGCs by comparing the lymph node metastasis risk (LNMR) and the surgical risk., Methods: We retrospectively identified 485 patients with differentiated-type, noncurative EGCs removed by ESD and classified them into two groups: a surgery-preferable group and an observation-preferable group, according to the clinical courses. Subsequently, LNMR and surgery-related death risk were assessed using a published scoring system and a risk calculator for gastrectomy, respectively. Finally, we investigated the optimal cutoff value of the risk difference (LNMR minus surgery-related death risk) to efficiently allocate these cases into either of two groups, surgery-preferable or observation-preferable., Results: In 485 patients (surgery in 322, observation in 163), 57 and 428 patients were classified into the surgery-preferable group and the observation-preferable group, respectively. The optimal cutoff value of the risk difference (LNMR minus surgery-related death risk) to allocate the cases to the two preferable groups was 7.85 with the highest area under the curve (0.689). When cases with >7.85 LNMR over the surgery-related death risk were allocated into the surgery-preferable group and vice versa, the discriminability was 73.2%, which was sufficiently higher than that in the clinical decision (44.5%)., Conclusion: Personalized comparison of LNMR and surgery-related death risk is helpful to provide a favorable treatment option for each patient with EGCs after noncurative ESD., (© 2022 S. Karger AG, Basel.)