The PillCam patency capsule (PC) without a radio frequency identification tag was released to preclude retention of the small bowel capsule endoscope (CE) in Japan in 2012. We conducted a multicenter study to determine tag-less PC-related adverse events (AEs). We first conducted a retrospective survey using a standardized data collection sheet for the clinical characteristics of PC-related AEs among 1096 patients collected in a prospective survey conducted between January 2013 and May 2014 (Cohort 1). Next, we retrospectively investigated additional AEs that occurred before and after Cohort 1 within the period June 2012 and December 2014 among 1482 patients (Cohort 2). Of the 2578 patients who underwent PC examinations from both cohorts, 74 AEs occurred among 61 patients (2.37%). The main AEs were residual parylene coating in 25 events (0.97%), PC-induced small bowel obstruction, suspicious of impaction, in 23 events (0.89%), and CE retention even after patency confirmation in 10 events (0.39%). Residual parylene coating was significantly associated with Crohn's disease (P < 0.01). Small bowel obstruction was significantly associated with physicians with less than 1 year of experience handling the PC and previous history of postprandial abdominal pain (P < 0.01 and P < 0.03, respectively). CE retention was ascribed to erroneous judgment of PC localization in all cases. This large-scale multicenter study provides evidence supporting the safety and efficiency of a PC to preclude CE retention. Accurate PC localization in patients without excretion and confirmation of previous history of postprandial abdominal pain before PC examinations is warranted (UMIN000010513).

Mitochondrial dysfunction plays a crucial role in the progression of non-alcoholic steatohepatitis (NASH). Mitochondrial division inhibitor 1 (Mdivi1) is a potential inhibitor of dynamin-related protein (Drp1) and mitochondrial fission. However, the therapeutic effect of Mdivi1 against NASH and its underlying molecular mechanisms remain unclear. In this study, we established mouse models of NASH by inducing high-fat/high-cholesterol (HFHC) or methionine- and choline-deficient (MCD) diets and treated the animals with 5mg/kg/day Mdivi1 or placebo. Treatment with Mdivi1 significantly alleviated diet-induced fatty liver phenotypes, including increased liver weight/body weight ratio, insulin resistance, hepatic lipid accumulation, steatohepatitis, and liver injury. Furthermore, Mdivi1 treatment suppressed HFHC or MCD diet-induced changes in the expression of genes related to lipid metabolism and inflammatory cytokines. Additionally, Mdivi1 reduced macrophage infiltration in the injured liver and promoted polarization of macrophages towards the M1 phenotype. At the molecular level, Mdivi1 attenuated mitochondrial fission by reducing Drp1 activation and expression, thereby decreasing mitochondrial reactive oxygen species accumulation and mitochondrial DNA damage. Moreover, Mdivi1-treated mice exhibited elevated levels of phosphorylated-c-Jun N-terminal kinase (p-JNK), mitochondrial fission factor (MFF), cleaved caspase 3 protein, and TUNEL-positive cell expression in the liver, suggesting that Mdivi1 might ameliorate mitochondrial dysfunction and reduce hepatocyte apoptosis by inhibiting the JNK/MFF pathway. Collectively, Mdivi1 protected against diet-induced NASH by restoring mitochondrial homeostasis and function, potentially through its inhibitory effect on the JNK/MFF pathway. Consequently, further investigation of Mdivi1 as a promising drug for NASH treatment is warranted.

Although small-bowel capsule endoscopy (CE) is widely used for obscure gastrointestinal bleeding (OGIB), long-term outcomes for OGIB patients after negative CE remain unclear. Herein, we defined negative CE as P0 (no bleeding potential) or P1 (less likely to bleed), based on the P classification using CE. We aimed to clarify long-term outcomes of patients with OGIB after negative CE. This single-center observational study enrolled 461 consecutive patients with OGIB who underwent CE from March 2014 to October 2021 and were followed up for >1year. We examined rebleeding rates and predictive factors. Two hundred and twenty-four (49%) patients had P0, and 237 (51%) had P1 findings. Rebleeding occurred in 9% and 16% of patients in the P0 and P1 groups, respectively. Two patients in the P0 group and 15 in the P1 group showed rebleeding from the small bowel. The rate of small-bowel rebleeding was significantly lower in the P0 group than that in the P1 group (1% vs 6%, P=0.002), as was the cumulative rebleeding rate (P=0.004). In the multivariate analysis, history of endoscopic hemostasis (hazard ratio [HR]=15.958, 95% confidence interval [CI]:4.950-51.447, P<0.001) and P1 CE findings (HR=9.989, 95% CI: 2.077-48.030, P=0.004) were independently predicted small-bowel rebleeding. OGIB with P0 CE findings rarely showed rebleeding from the small bowel. Rebleeding may occur in patients with OGIB. Patients with history of endoscopic hemostasis for small-bowel lesions or P1 CE findings should be followed up intensively.

Convolutional neural network (CNN) systems that automatically detect abnormalities from small-bowel capsule endoscopy (SBCE) images are still experimental, and no studies have directly compared the clinical usefulness of different systems. We compared endoscopist readings using an existing and a novel CNN system in a real-world SBCE setting. Thirty-six complete SBCE videos, including 43 abnormal lesions (18 mucosal breaks, 8 angioectasia, and 17 protruding lesions), were retrospectively prepared. Three reading processes were compared: (A) endoscopist readings without CNN screening, (B) endoscopist readings after an existing CNN screening, and (C) endoscopist readings after a novel CNN screening. The mean number of small-bowel images was 14747 per patient. Among these images, existing and novel CNN systems automatically captured 24.3% and 9.4% of the images, respectively. In this process, both systems extracted all 43 abnormal lesions. Next, we focused on the clinical usefulness. The detection rates of abnormalities by trainee endoscopists were not significantly different across the three processes: A, 77%; B, 67%; and C, 79%. The mean reading time of the trainees was the shortest during process C (10.1min per patient), followed by processes B (23.1min per patient) and A (33.6min per patient). The mean psychological stress score while reading videos (scale, 1-5) was the lowest in process C (1.8) but was not significantly different between processes B (2.8) and A (3.2). Our novel CNN system significantly reduced endoscopist reading time and psychological stress while maintaining the detectability of abnormalities. CNN performance directly affects clinical utility and should be carefully assessed.

Strategies to reduce relapse using immunomodulators (IMs) after discontinuing anti-tumor necrosis factor-alpha (TNF-α) antibody treatment are controversial in patients with ulcerative colitis (UC). In this study, we assessed the association between IMs after discontinuing anti-TNF-α antibody treatment and relapse in patients with UC. This retrospective, multicenter cohort study included 257 patients with UC in clinical remission. These patients discontinued anti-TNF-α antibody treatment between June 2010 and March 2019 and were followed up until March 2020. We evaluated the differences in relapse rates between patients with IMs (IM group) and those without IMs (non-IM group) after discontinuing the treatment. Relapse was defined as further undergoing an induction treatment or colectomy. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for relapse. Exploratory analyses were performed to identify other factors that could predict relapse. During the median follow-up period of 22months (interquartile range: 10-41), 114 relapses occurred: 42/100 (42.0%) in the IM group and 72/157 (45.9%) in the non-IM group. In the multivariable analysis, IMs were not associated with relapse (HR, 0.95 [95% CI, 0.64-1.41]). In the exploratory analyses, discontinuation due to side effects (HR, 1.83 [95% CI, 1.18-2.82]) and younger age (HR, 0.99 [95% CI, 0.98-1.00]) predicted relapse. Immunomodulators were not associated with relapse after discontinuing anti-TNF-α antibody treatment in patients with UC. Careful patient follow-up is needed when discontinuing due to side effects or when the patient is of a younger age at the time of discontinuation.

Delayed bleeding is a rare but important major adverse event (mAE) after endoscopic submucosal tunneling procedures (ESTP), which is scarcely reported. We aimed to characterize the clinical characteristics of delayed bleeding and provide better management of this mAE. From August 2010 to October 2022, we reviewed 3852 patients with achalasia receiving peroral endoscopic myotomy (POEM) and 1937 patients with upper gastrointestinal tumors receiving submucosal tunneling endoscopic resection (STER). Among these, records of 22 patients (15 POEM, 7 STER) with delayed bleeding were collected. Clinical characteristics, treatment, and outcomes of delayed bleeding were analyzed. The mean age was 43.6years. Ten patients (45.5%) were intratunnel bleeding, seven (31.8%) were intratunnel bleeding accompanied by mucosal bleeding, and five (22.7%) were mucosal bleeding. The most common accompanied symptoms were hematemesis, fever, and melena. The most common accompanied mAEs were fistula, pulmonary inflammation, and pleural effusion with atelectasis. The mean duration from ESTP to endoscopic intervention was 5.3±4.9days. Active bleeding was identified in 21 patients (95.5%). The bleeding was successfully controlled by electrocoagulation (19 cases), endoscopic clipping (six cases), and Sengstaken-Blakemore tube insertion (three cases), and no patient required surgical intervention. The mean hemostatic procedure duration was 61.8±45.8min. The mean post-bleeding hospital stay was 10.0±6.2days. A brief meta-analysis of previous studies showed the pooled estimate delayed bleeding rate after POEM, STER, and G-POEM was 0.4%. Delayed bleeding is uncommon and could be effectively managed by timely emergency endoscopic procedures without requiring subsequent surgical interventions.

Necroptosis is an emerging cell death pathway that allows cells to undergo "cellular suicide" in a caspase-independent manner. We investigated the fate of hepatic stellate cells (HSCs) under necroptotic stimuli. The RNA level of mixed lineage kinase domain-like protein (MLKL) is higher in patients with non-alcoholic fatty liver disease than in healthy controls. Hepatic fibrosis was significantly lower in MLKL-KO bile duct ligation (KO-BDL) mice than in wild-type-BDL mice. Necroptotic stimuli caused the death of HT-29 and U937 cells. However, necroptotic stimuli activate HSCs instead of inducing cell death. MLKL inhibitors attenuated fibrogenic changes in HSCs during necroptosis. Unlike HT-29 and U937 cells, MLKL phosphorylation and oligomerization were not observed during necroptosis in HSCs. RNA sequencing showed that NF-κB signaling-related genes were upregulated in HSCs following necroptotic stimulation. Necroptotic stimuli in HSCs increased the nuclear expression of NF-κB, which decreased after MLKL inhibitor treatment. Induction of necroptosis in HSCs led to autophagosome activation and formation, which were attenuated by MLKL inhibitor treatment. HSCs avoid necroptosis due to the absence of MLKL phosphorylation and oligomerization and are activated through autophagosome and NF-κB pathways.

Our prior research revealed that the tumor enhancement ratio (TER) on triphasic abdominal contrast-enhanced MDCT (CE-MDCT) scans was a prognostic factor for patients with stages I-III colon cancer. Building upon this finding, the present study aims to investigate the proteomic changes in colon cancer patients with varying TER values. TER was analyzed on preoperative triphasic CE-MDCT scans of 160 stages I-III colon cancer patients. The survival outcomes of those in the low-TER and high-TER groups were compared. Proteomic analysis on colon cancer tissues was performed by mass spectrometry (MS) and verified by immune-histological chemistry (IHC) assays. In vivo, mouse xenograft models were employed to test the function of target proteins identified through the MS. CE-MDCT scans were conducted on mice xenografts, and the TER values were compared. Patients in the high-TER group had a significantly worse prognosis than those in the low-TER group. Proteomic analysis of colon cancer tissues revealed 153 differentially expressed proteins between the two groups. A correlation between TER and the abundance of α-SMA protein in tumor tissue was observed. IHC assays further confirmed that α-SMA protein expression was significantly increased in high-TER colon cancer, predominantly in cancer-associated fibroblasts (CAFs) within the cancer stroma. Moreover, CAFs promoted the growth of CRC xenografts in vivo and increased TER. Our study identified the distinct protein changes in colon cancer with low and high TER for the first time. The presence of CAFs may promote the growth of colon cancer and contribute to an increased TER.