Exercise Affects Mucosa-Associated Microbiota and Colonic Tumor Formation Induced by Azoxymethane in High-Fat-Diet-Induced Obese Mice.

The only reliable factor that reduces the risk of colorectal carcinogenesis is physical activity. However, the underlying mechanisms remain unclear. In this study, we examined the effects of physical activity against gut microbiota, including mucosa-associated microbiota (MAM) on azoxymethane-induced colorectal tumors in obese mice. We divided the subjects into four groups: normal diet (ND), high-fat diet (HFD), ND + exercise (Ex), and HFD + Ex groups. The Ex group performed treadmill exercise for 20 weeks. Thereafter, fecal and colonic mucus samples were extracted for microbiota analysis. DNA was collected from feces and colonic mucosa, and V3-V4 amplicon sequencing analysis of the 16SrRNA gene was performed using MiSeq. The HFD group had significantly more colonic polyps than the ND group (ND 6.5 ± 1.3, HFD 11.4 ± 1.5, p < 0.001), and the addition of Ex suppressed the number of colonic polyps in ND and HFD groups (ND 6.5 ± 1.3, ND + Ex 2.8 ± 2.5, p < 0.05). The HFD group showed significantly lower concentrations of succinic, acetic, butyric, and propionic acids (mg/g) in feces, compared with the ND group (succinic acid HFD 0.59, ND 0.17; acetic acid HFD 0.63, ND 2.41; propionic acid HFD 0.10, ND 0.47; and N-butyric acid HFD 0.31, ND 0.93). In the case of ND, succinic acid and butyric acid tended to decrease with Ex (succinic acid ND 0.17, ND + Ex 0.12; N-butyric acid ND 0.93, ND + Ex 0.74 0.74). Succinic acid, acetic acid, butyric acid, and propionic acid levels in feces were significantly lower in the HFD group than in the ND group; in both feces and mucus samples, Butyricicoccus and Lactobacillus levels were significantly lower in the HFD group. Akkermansia was significantly increased in ND + Ex and HFD + Ex groups. Diet and exercise affected the number of colorectal tumors. Furthermore, diet and exercise alter intestinal MAM, which may be involved in colorectal tumor development.

Factors Associated with Overlap between Functional Dyspepsia and Nonerosive Reflux Disease in Endoscopy-based Helicobacter pylori-uninfected Japanese Health Checkup Participants: A Prospective, Multicenter Cross-sectional Study.

Objective We assessed the factors associated with overlap between functional dyspepsia (FD) and nonerosive reflux disease (NERD) in endoscopy-based Helicobacter pylori-uninfected Japanese health checkup participants. Methods We utilized baseline data from 3,085 individuals who underwent upper endoscopy for health screening in a prospective, multicenter cohort study. The participants were asked to complete a questionnaire detailing their upper abdominal symptoms and lifestyle. Anxiety was assessed using the State-Trait Anxiety Inventory (STAI) score. FD, postprandial distress syndrome (PDS), and epigastric pain syndrome (EPS) were defined according to the Rome III criteria. NERD was defined as heartburn or regurgitation ≥1 day/week without erosive esophagitis. Results Of the 3,085 participants, 73 (2.4%), 97 (3.1%), and 84 (2.7%) had FD alone, NERD alone, and FD-NERD overlap, respectively. Factors associated with FD-NERD-overlap participants compared with participants with neither FD nor NERD were women [odds ratio (OR): 2.08, 95% confidence interval (CI): 1.24-3.52], body mass index (BMI) <18.5 (OR: 2.87, 95% CI: 1.56-5.07), alcohol consumption ≥20 g/day (OR: 1.85, 95% CI: 1.06-3.15), and a high STAI score (OR: 2.53, 95% CI: 1.62-4.00). Increasing age (OR: 1.06, 95% CI: 1.01-1.11) and EPS symptoms [pure EPS (OR: 3.67, 95% CI: 1.65-8.51) and PDS-EPS overlap (OR: 11.6, 95% CI: 4.09-37.2)] were associated with FD-NERD overlap vs. FD alone. Women (OR: 3.17, 95% CI: 1.47-7.04), BMI <18.5 (OR: 3.03, 95% CI: 1.04-9.90), and acid reflux symptoms ≥2 days a week (OR: 3.57, 95% CI: 1.83-7.14) were associated with FD-NERD overlap vs. NERD alone. Conclusion Understanding the clinical features of overlap between FD and NERD will lead to better management.

Reduced abundance of butyric acid-producing bacteria in the ileal mucosa-associated microbiota of ulcerative colitis patients.

Compositional changes in the microbiota are associated with various inflammatory diseases, including ulcerative colitis (UC). Aim: This study aimed to investigate the mucosa-associated microbiota (MAM) in patients with UC and its difference related with disease activity and classification. Brush samples were collected from the terminal ileum and sigmoid colon during endoscopic procedures. The microbiota of samples was profiled using the Illumina MiSeq platform. The V3-V4 regions of the gene encoding 16S rRNA (460 bp) were amplified using PCR. Fifty UC patients and twenty healthy controls were enrolled. UC patients displayed significantly reduced α-diversity in both the ileum and sigmoid colon compared to controls. A difference in ß-diversity in the unweighted analysis was observed between the two groups. The abundance of Lactobacillus and Veillonella was significantly higher and that of Butyricicoccus, Ruminococcus and Lachnospiraceae was significantly lower in the ileum of UC patients than in controls. The abundance of Odoribacter in the ileum was significantly lower in left-sided colitis and pancolitis patients than in proctitis patients and lower in patients with highly severe disease activity than with mild disease activity. The reduction in abundance of butyric acid-producing bacteria, especially Odoribacter, in ileal MAM may play an important role in the pathophysiology of UC.

Reduction of butyric acid-producing bacteria in the ileal mucosa-associated microbiota is associated with the history of abdominal surgery in patients with Crohn's disease.

Fecal microbiota is a significant factor determining the cause, course, and prognosis of Crohn's disease (CD). However, the factors affecting mucosa-associated microbiota (MAM) remain unclear. This retrospective study examined the differences in ileal MAM between CD patients and healthy controls and investigated the factors affecting MAM in CD patients to clarify potential therapeutic targets. Ileal MAM was obtained using brush forceps during endoscopic examination from 23 healthy controls and 32 CD patients (most were in remission). The samples' microbiota was profiled using the Illumina MiSeq platform. Compared to controls, CD patients had significantly reduced α-diversity in the ileum and a difference in ß-diversity. The abundance of butyric acid-producing bacteria in the ileal MAM was significantly lower in CD patients with a history of abdominal surgery than in those without. Because butyric acid is a major energy source in the intestinal epithelium, its metabolism via ß-oxidation increases oxygen consumption in epithelial cells, reducing oxygen concentration in the intestinal lumen and increasing the abundance of obligate anaerobic bacteria. The suppression of obligate anaerobes in CD patients caused an overgrowth of facultative anaerobes. Summarily, reducing the abundance of butyric acid-producing bacteria in the ileal MAM may play an important role in CD pathophysiology.

Assessment of predictive factors associated with the technical difficulty of endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma: Japanese multicenter retrospective study.

OBJECTIVES: Endoscopic submucosal dissection (ESD) for superficial esophageal squamous cell carcinoma (ESCC) is performed for the treatment of lesions with varied backgrounds and factors. However, the predictive factors associated with the technical difficulty of ESD remain unknown in patients with varied lesions. Therefore, this study aimed to identify the predictive factors associated with the technical difficulty of ESD for ESCC using a retrospective cohort. METHODS: This multicenter, retrospective study was conducted in 10 hospitals in Japan. Consecutive patients who underwent esophageal ESD between January 2013 and December 2019 were enrolled. Lesions of subepithelial tumors, adenocarcinoma, and adenoma were excluded. Difficult lesions were defined as ESD requiring a long procedure time (≥120 min), perforation development, piecemeal resection, or discontinued ESD. In the present study, the clinical factors were assessed to identify the technical difficulty of ESD using univariate and multivariate analyses. RESULTS: Among 1708 lesions treated with esophageal ESD, eight subepithelial tumors, 44 adenocarcinomas, and two adenomas were excluded. Finally, 1505 patients with 1654 lesions were analyzed, and 217 patients with 217 lesions (13.1%) were classified as patients with difficult lesions. In multivariate analysis, the predictive factors associated with the technical difficulty of ESD were as follows: tumors with varices, tumors with diverticulum, antiplatelet use (discontinued), circumference of tumor (≥1/2), preoperative tumor size ≥30 mm, trainee, and nonhigh-volume center. CONCLUSION: This multicenter retrospective study identified the predictive factors associated with the technical difficulty of ESD for ESCC with varied backgrounds and factors.

Long-Term Outcomes of Endoscopic Submucosal Dissection for Early Remnant Gastric Cancer: A Retrospective Multicenter Study.

INTRODUCTION: Favorable long-term outcomes of endoscopic submucosal dissection (ESD) for early remnant gastric cancer (ERGC) have been reported in single-center studies from advanced institutions. However, no studies have examined the long-term outcomes using a multicenter database. This study aimed to investigate the long-term outcomes of the aforementioned approach using a large multicenter database. METHODS: This retrospective multicenter cohort study included 242 cases with 256 lesions that underwent ESD for ERGC between April 2009 and March 2019 across 12 centers. We investigated the long-term outcomes of these patients with the Kaplan-Meier method, and the relationship between curability, additional treatment, or hospital category, and the survival time was evaluated using the log-rank test. RESULTS: During the median follow-up period of 48.4 months, the 5-year overall survival rate was 81.3%, and the 5-year gastric cancer-specific survival rate was 98.1%. The survival time of patients of endoscopic curability (eCura) C-2 without additional surgery was significantly shorter than the corresponding of patients of eCura A/B/C-1 and eCura C-2 with additional surgery. There was no significant difference in either overall survival or gastric cancer-specific survival rate between the high-volume and non-high-volume hospitals. CONCLUSION: The gastric cancer-specific survival of ESD for ERGC using a multicenter database was favorable. ESD for ERGC is widely applicable regardless of the hospital case volume. Management in accordance with the latest guidelines will lead to long-term survival.

Linked Color Imaging for Stomach.

Image-enhanced endoscopy (IEE) plays an important role in the detection and further examination of gastritis and early gastric cancer (EGC). Linked color imaging (LCI) is also useful for detecting and evaluating gastritis, gastric intestinal metaplasia as a pre-cancerous lesion, and EGC. LCI provides a clear excellent endoscopic view of the atrophic border and the demarcation line under various conditions of gastritis. We could recognize gastritis as the lesions of the diffuse redness to purple color area with LCI. On the other hand, EGCs are recognized as the lesions of the orange-red, orange, or orange-white color area in the lesion of the purple color area, which is the surround atrophic mucosa with LCI. With further prospective randomized studies, we will be able to evaluate the diagnosis ability for EGC by IEE, and it will be necessary to evaluate the role of WLI/IEE and the additional effects of the diagnostic ability by adding IEE to WLI in future.

Comparison of mucosa-associated microbiota in Crohn's disease patients with and without anti-tumor necrosis factor-α therapy.

Most studies on the gut microbiome of Crohn's disease have been conducted using feces, instead of intestinal mucus to analyze the mucosa-associated microbiota. To investigate the characteristics of mucosa-associated microbiota in Crohn's disease patients and the effect of anti-tumor necrosis factor (TNF)-α therapy on mucosa-associated microbiota, we analyzed microbiota in Crohn's disease patients using brushing samples taken from terminal ileum. The recruited subjects were 18 Crohn's disease patients and 13 controls. There were 10 patients with anti-TNF-α therapy in Crohn's disease group. Crohn's disease patients had significantly reduced α-diversity in Shannon index compared to the controls. The comparative analysis of the taxonomic composition at the genus level between the Crohn's disease group and the controls indicated that butyrate-producing bacteria were less abundant in the Crohn's disease group compared to the controls. There were no differences in the diversity between the patients taking anti-TNF-α therapy and the patients without. The comparative analysis of the taxonomic composition at the genus level between the two groups indicated that some of anti-inflammatory bacteria were less abundant in the anti-TNF-α therapy group than the other. Reduction of specific bacteria producing anti-inflammatory molecules, especially butyrate-producing bacteria may play important roles in the pathophysiology of Crohn's disease.

The risk scoring system for assessing the technical difficulty of endoscopic submucosal dissection in cases of remnant gastric cancer after distal gastrectomy.

BACKGROUND: Endoscopic submucosal dissection (ESD) for remnant gastric cancer (RGC) after distal gastrectomy (DG) is considered technically challenging due to the narrow working space, and severe fibrosis and staples from the previous surgery. Technical difficulties of ESD for RGC after DG have not been thoroughly investigated. This study aimed to develop and validate a risk-scoring system for assessing the technical difficulty of ESD for RGC after DG in a large multicenter cohort. METHODS: We investigated patients who underwent ESD for RGC after DG in 10 institutions between April 2008 and March 2018. A difficult case was defined as ESD lasting ≥ 120 min, involving piecemeal resection, or the occurrence of perforation during the procedure. A risk-scoring system for the technical difficulty of the procedure was developed based on multiple logistic regression analyses, and its performance was internally validated using bootstrapping. RESULTS: A total of 197 consecutive patients with 201 lesions were analyzed. There were 90 and 111 difficult and non-difficult cases, respectively. The scoring model consisted of four independent risk factors and points of risk scores were assigned for each as follows: tumor size > 20 mm: 2 points; anastomosis site: 2 points; suture line: 1 point; and non-expert endoscopist: 2 points. The C-statistics of the scoring system for technical difficulty was 0.72. CONCLUSIONS: We developed a validated risk-scoring model for predicting the technical difficulty of ESD for RGC after DG that can contribute to its safer and more reliable performance.

P2Y12 Inhibitors Exacerbate Low-dose Aspirin-induced Small Bowel Injury in Dual Antiplatelet Therapy.

Objective Antithrombotic drugs are being used increasingly frequently to prevent cardiovascular diseases. Few studies have evaluated small bowel mucosal injury induced by dual antiplatelet therapy (DAPT). The aim of the present study was to evaluate small bowel mucosal injury induced by DAPT compared with other antithrombotics using video capsule endoscopy (VCE). Methods The study included chronic users of antithrombotics who underwent VCE for obscure gastrointestinal bleeding between January 2007 and July 2018. We evaluated the instances of small bowel injury classified into erosions and ulcers. Results Overall, 183 patients (114 men and 69 women; mean age, 73.6 years old) were enrolled, and the study groups comprised 49 patients taking low-dose aspirin (LDA) only, 50 taking anticoagulants only, 37 being treated with DAPT, 33 on combined LDA and anticoagulants, and 14 taking P2Y12 inhibitors. Small bowel erosions and ulcers were most frequently observed in the DAPT group, with frequencies of 78.4% and 37.8%, respectively. Exacerbating factors of small bowel ulcers were DAPT [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.2-7.7] and age over 80 years old (OR 2.4, 95% CI 1.1-5.4). Conclusion P2Y12 inhibitors seem to exacerbate LDA-induced small bowel injury. Preventive strategies for small bowel injury induced by LDA, especially DAPT, are urgently required.

Usefulness of radiographic targeting on the evaluation of the location of a patency capsule using abdominal ultrasonography.

BACKGROUND AND AIM: The usefulness of a radio-tag-free PillCam patency capsule (PatCap) has been reported to evaluate the patency of the small intestine. If the PatCap is not excreted within 33 h, the location of the failed PatCap must be confirmed. Although several methods for locating the failed PatCap have been reported, a universal method has not been established. In this study, we aimed to confirm the clinical feasibility of abdominal ultrasonography combined with abdominal X-ray in the determination of the location of a failed PatCap. PATIENTS AND METHODS: Consecutive patients who were scheduled to undergo the capsule endoscopy and had received PatCap examination between July 2012 and September 2019 were retrospectively analyzed. Failed PatCap was assessed using ultrasonography combined with abdominal X-ray. RESULTS: Among the eligible 250 patients, 129 retrieved the PatCap in their stool within 33 h after ingestion. Among the remaining 121 patients, abdominal X-ray was performed and the PatCaps were suspected to be in the small bowel in 57 patients. Among these 57 patients, abdominal ultrasonography identified 17 PatCaps in the small bowel. Among the selected 250 patients, 233 patients (93.2%) were eligible for capsule endoscopy examination, while 17 patients (6.8%) were not eligible. Capsule endoscopy passed through the small intestine without any incident. CONCLUSION: We confirmed that the abdominal ultrasonography with a radiographic targeting of the PatCap location is a reliable indicator to avoid the risk of capsule endoscopy retention or impaction and can be performed in most hospitals and clinics.

Evaluation of efficacy and safety of lubiprostone in patients with chronic constipation.

OBJECTIVES: Lubiprostone is an apical type 2 chloride channel activator approved for the treatment of chronic constipation (CC), and nausea is the most common adverse symptom. However, the associated factors with the efficacy and the precise mechanism of nausea remain unclear. The aim of this study is to characterize clinical backgrounds related with the efficacy and the adverse symptoms of lubiprostone. MATERIALS AND METHODS: Subjects were patients with CC who were prescribed lubiprostone from April 2017 to October 2019. The efficacy and safety of lubiprostone were retrospectively examined using the electronic medical record. RESULTS: Hundred and fifty-five patients (76 men, and mean age 69) were evaluated. Lubiprostone was effective in 74 patients (47.8%), and the discontinuation due to adverse in 34 patients (21.9%). including nausea, diarrhea and abdominal pain in 16, 12 and 3 patients, respectively. The efficacy was significantly associated with gender, age, body mass index (BMI), diabetes mellitus, hypertension, calcium channel blockers and antipsychotics. In multivariate analysis, the efficacy was significantly associated with men (odds ratio [OR], 3.21; 95% confidence interval (CI), 1.42-7.27) and BMI (OR, 1.14; 95% CI, 1.02-1.28). The incidence of nausea was higher in patients under 65 years old, and hypertension was the significant protective factor for nausea. CONCLUSIONS: Lubiprostone was effective for men patients with CC, and hypertension seems to be the protective factor for nausea.

A novel gene associated with small bowel bleeding in patients taking low-dose aspirin.

OBJECTIVE: We have previously revealed the clinical factors and genetic polymorphisms associated with gastrointestinal mucosal injury and bleeding, induced by low-dose aspirin (LDA). After performing genome-wide analysis of single nucleotide polymorphisms (SNPs) using the Drug Metabolizing Enzymes and Transporters (DMET) system among drug metabolism and transporter genes, certain SNPs were found to increase the risk for LDA-induced small bowel bleeding. The aim of this study was to identify the SNPs involved in LDA-induced small bowel bleeding. SUBJECTS AND METHODS: Subjects were patients taking LDA, with small bowel bleeding diagnosed using capsule endoscopy. We investigated the clinical characteristics and the previously identified SNPs, that were examined by the DNA direct sequence method. RESULTS: 56 patients with bleeding and 410 controls taking LDA were enrolled. The risk factors associated with small bowel bleeding included smoking, cerebrovascular diseases, chronic renal failure, non-steroidal anti-inflammatory drug (NSAID) or anticoagulants combination, and two SNPs (CYP4F11 20043G>A (D446N) rs1060463, GSTP1 313A>G rs1695). After propensity score matching, GSTP1 rs1695 was significantly associated with small bowel bleeding. CONCLUSION: The GSTP1 SNP may be a predictive marker for small bowel bleeding among patients taking LDA.

Evaluation of Performance in Colon Capsule Endoscopy Reading by Endoscopy Nurses.

Background: Although there are papers reporting on the accuracy of colon capsule endoscopy (CCE) compared with colonoscopy (CS), there are few reports on the detection rates of significant lesions by endoscopy nurses. We previously reported no significant difference in the detection rates for small bowel capsule endoscopy (SBCE) images among two well-trained physicians and one expert nurse. Objective: To evaluate the reading time and detection rate of the significant lesions of CCE images among novice and trained expert endoscopy nurses and novice physicians. Methods: CCE videos of 20 consecutive patients who performed both CCE and CS with clinically significant localized lesions were selected. Two trained expert endoscopy nurses, untrained two novice physicians, and novice three endoscopy nurses reviewed CCE videos. The detection rate of the lesions and reading time were compared among the three groups and were evaluated by comparison between the first and the second 10 videos. Results: The median reading time was the shortest (19 min) in the trained expert endoscopy nurses and the longest (45 min) in the novice nurses. The number of thumbnails tended to be more in the trained expert endoscopy nurses in the first 10-video reading. Although the detection rates of small polyps (<5 mm) were significantly lower (46.5%, p=0.025) in the novice nurses compared to the others, they were improved (35.2% to 63.5%, p=0.015) in the second 10 videos. The detection rates of tumor lesions by either one of two trained expert endoscopy nurses were higher compared to those by each novice physician. Conclusions: The trained expert endoscopy nurses for CCE reading can reduce physician's time and improve the diagnostic yield.

Fibrin glue: Novel submucosal injection agent for endoscopic submucosal dissection.

Background and study aims Adequate mucosal elevation by submucosal injection is crucial for patient safety and efficiency during endoscopic submucosal dissection (ESD). This study aimed to evaluate the efficacy of fibrin glue (FG) as a long-lasting submucosal injection agent and to evaluate the technical feasibility of FG injection for ESD. Materials and methods To compare the capabilities of different agents in maintaining submucosal evaluation, we injected FG, hyaluronic acid solution, and normal saline into the porcine gastric specimen that was incised into approximately 5 × 5 cm squares. Then, we measured the height of submucosal elevations over time. Moreover, three hypothetical lesions from the resected porcine stomach underwent ESD with FG injection. Thereafter, we conducted macroscopic and histopathologic analyses. Results FG maintained the greatest submucosal elevation among all the injection agents. Three ESD procedures were performed with en bloc resection. Both macroscopic and histopathologic findings showed a thick FG clot on the ulcers. Conclusions The FG solution can be potentially used as an ESD submucosal injection agent in an in vitro model.

PDZK1 induces resistance to apoptosis in esophageal adenocarcinoma cells.

BACKGROUND: Esophageal cancer is a lethal malignancy with a poor prognosis. The incidence of esophageal adenocarcinoma, which develops from Barrett's esophagus (BE), has recently been increasing. In a previous study, we found that PDZK1 expression is higher in long segment BE compared to that in short-segment BE. However, the function of PDZK1 in the mucosa of BE is unclear. AIMS: Clarify the role of PDZK1 in BE mucosa using PDZK1 overexpressed cells. METHODS: Human adenocarcinoma-derived OE33 cells were used as a parental cell line and transfected to generate PDZK1 overexpressed OE33 cells (PC cells) or transfected with empty vector as control cells (NC cells). Cell growth of NC and PC cells in 10% fetal bovine serum was evaluated by cell counting. The effect of PDZK1 on proteasome inhibitor (PSI)-induced apoptosis was qualified by fluorescence microscopy and quantified by flow cytometry. Expression of apoptosis-related proteins was evaluated by western blotting. RESULTS: There were no significant differences in cell growth between NC and PC cells. PSI significantly increased apoptosis in NC cells, but not in PC cells. In response to PSI, increased levels of cleaved-caspase3 and decreased pro-caspase3 levels were found in NC cells, but not in PC cells. In NC cells, PSI significantly decreased Bcl-2 expression without affecting Bax levels. In contrast, high expression of both Bcl-2 and Bax was observed in PC cells. CONCLUSION: Overexpression of PDZK1 protein induces an apoptosis-resistant phenotype in BE cells, which may be a potential therapeutic target.

Development and validation of an endoscopic submucosal dissection video assessment tool.

BACKGROUND: Despite a need for assessment of endoscopic submucosal dissection (ESD) skills in order to track progress and determine competence, there is no structured measure of assessing competency in ESD performance. The present study aims to develop and examine validity evidence for an assessment tool to evaluate the recorded performance of ESD for gastric neoplasms. METHODS: The ESD video assessment tool (EVAT) was systematically developed by ESD experienced endoscopists. The EVAT consists of a 25-item global rating scale and 3-item checklist to assess competencies required to perform ESD. Five unedited videos were each evaluated by 2-blinded experienced ESD endoscopists to assess inter-rater reliability using intraclass correlation coefficients (ICC). Seventeen unedited videos in total were rated by 3 blinded experienced ESD endoscopists. Validity evidence for relationship to other variables was examined by comparing scores of inexperienced (fellows) and experienced endoscopists (attending staff), and by evaluating the relationship between the EVAT scores and ESD case experience. Internal consistency was evaluated using Cronbach's alpha. RESULTS: The inter-rater reliability for the total score was high at 0.87 (95% confidence interval 0.11 to 0.99). The total score [median, interquartile range (IQR)] was significantly different between the inexperienced (71, 63-77) and experienced group (95, 91-97) (P = 0.005). The total scores demonstrated high correlation with the number of ESD cases (Spearman's ρ = 0.79, P < 0.01). The internal consistency was 0.97. CONCLUSIONS: This study provides preliminary validity evidence for the assessment of video-recorded ESD performances for gastric neoplasms using EVAT.

Molecular biomarker identification for esophageal adenocarcinoma using endoscopic brushing and magnified endoscopy.

BACKGROUND: Barrett's esophagus (BE) is a predisposing factor for esophageal adenocarcinoma (EAC); however, the precise mechanism underlying this association remains unclear. The identification of biomarkers that are associated with an increased risk of BE progression to EAC would facilitate diagnosis and early treatment. Toward this goal, we aimed to identify biomarkers associated with BE and EAC in patients. METHODS: In conjunction with high-resolution magnified endoscopy with narrow-band imaging (ME-NBI), we obtained brushing samples from the long-segment BE (LSBE) or short-segment BE (SSBE) of patients with EAC or without EAC (control). To identify candidate biomarker genes, microarray analysis was performed for a training set of 28 American samples. To confirm the microarray results, expression levels of the 16 candidate biomarkers were evaluated by real-time polymerase chain reaction analysis, using samples collected from an additional 53 American patients. In addition, we also performed a functional analysis for these genes using Gene Ontology (GO) enrichment analysis. RESULTS: Among the 16 genes identified as differentially expressed by microarray analysis, the GO analysis indicated matrix metalloproteinase (MMP) family associated with 'collagen metabolic process' and 'multicellular organismal macromolecule metabolic process' as the two top biological processes. Brushing samples of patients with EAC showed up-regulated expression of decay-accelerating factors (DAF and CD55) and topoisomerase type Iiα (TOP2A), and down-regulated expression of the sodium channel epithelial 1 beta subunit (SCNN1B). CONCLUSIONS: The up-regulation of CD55 and TOP2A, and the down-regulation of SCNN1B were common to the brushing samples and might serve as molecular biomarkers for identifying EAC in patients with SSBE. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN) (000004004).

Endoscopic submucosal dissection involving the anal canal presents a risk factor for postoperative stricture.

BACKGROUND: Although postoperative strictures after endoscopic submucosal dissection (ESD) in the rectum are relatively rare, some rectal lesions require resection involving the anal canal, which is a narrow tract comprising squamous epithelium. To the best of our knowledge, no studies have investigated narrow anal canals when evaluating post-ESD strictures. This study aimed to evaluate the impact of resections involving the anal canal on postoperative stricture development. METHODS: Between April 2005 and October 2017, 707 rectal lesions were treated with ESD. We retrospectively investigated 102 lesions that required ≥ 75% circumferential resection. Risk factors for post-ESD stricture and, among patients with strictures, obstructive symptoms, and number of dilation therapies required were investigated. RESULTS: Post-ESD stricture occurred in 18 of 102 patients (17.6%). In the multivariate analysis, circumferential resection ≥ 90% and ESD involving the anal canal (ESD-IAC) were risk factors for postoperative strictures (P ≤ 0.0001 and 0.0115, respectively). Among the patients with strictures, obstructive symptoms were significantly related to anal strictures compared to rectal strictures (100% vs. 27.2%, P = 0.0041). Furthermore, the number of dilation therapies required was significantly greater among patients with anal strictures compared to those with rectal strictures (6.5 times vs. 2.7 times, P = 0.0263). CONCLUSION: Not only circumferential resection ≥ 90% but also ESD-IAC was a significant risk factor for the stricture after rectal ESD. Furthermore, anal strictures were associated with a significantly higher frequency of obstructive symptoms and larger number of required dilation therapies than were rectal strictures.