Phylogenetic Analysis and Characterization of Odorous Compound-Producing Actinomycetes in Sediments in the Sanbe Reservoir, A Drinking Water Reservoir in Japan.

Odor caused by the presence of geosmin and 2-methylisoborneol (2-MIB) in aquatic ecosystems leads to considerable economic loss worldwide. The odorous compounds are primarily produced by cyanobacteria and actinomycetes. While the contribution of odorous compounds-producing cyanobacteria has been thoroughly investigated, the production of geosmin and 2-MIB by actinomycetes in aquatic ecosystems is poorly understood. In this study, we isolated geosmin and/or 2-MIB-producing actinomycetes in sediments collected from the Sanbe Reservoir, Japan, identified the biosynthetic gene of geosmin and 2-MIB, and investigated the production of the odorous compounds by the isolated strains. Partial sequence of 16S rRNA and the biosynthetic genes was determined to analyze the phylogenetic relationship among the strains. The geosmin and 2-MIB concentrations in the culture of the isolated strains were measured using gas chromatography mass spectrometry. Fifty-four strains of odorous compounds-producing and non-geosmin-producing actinomycetes were isolated from sediments from the Sanbe Reservoir. Diverse actinomycetes were identified and many of them produced geosmin and/or 2-MIB. Many odorous compounds-producing actinomycetes were phylogenetically different from previously reported producing actinomycetes. The producing ability of the odorous compounds of the isolated strains in this study was not significantly related with the phylogenetic groups of 16S rRNA and the biosynthetic genes. The findings suggest that the odorous compounds-producing actinomycetes in the sediments are diverse and different from previously reported strains.

A case of anal canal carcinoma with pagetoid spread that was curatively resected by multiple endoscopic and surgical treatments.

A 57-year-old woman with no significant medical history was referred after a colonoscopy for abdominal distension, which revealed a tumor in the lower rectum. Pre-operative colonoscopy showed the tumor was 12 mm in size, located from the anorectal junction to beyond the dentate line, and was diagnosed as high-grade intramucosal neoplasia or shallow submucosal invasive cancer. Endoscopic submucosal dissection was performed, and the lesion was resected en bloc. Pathological examination revealed moderately differentiated tubular adenocarcinoma with tubulovillous adenoma. The stratified squamous epithelium adjacent to the anal side of the lesion showed pagetoid spread of atypical cells with positive horizontal margins. We referred her to a surgeon for radical treatment. The mucosa surrounding the endoscopic submucosal dissection scar was normal on narrow-band imaging magnification. We marked its oral side endoscopically as the resected boundary. Transanal local excision was performed. The horizontal margins were positive because atypical cells had spread into the stratified squamous epithelium of the anorectal side of the lesion. The patient was followed on an outpatient basis. Sixty days postoperatively, residual tumor growth was observed. The second local resection was performed after mapping biopsy. All resection margins were negative, there was no lymphovascular invasion. One year after surgery, no recurrence was observed. Regarding endoscopic findings, there are no reports of endoscopic findings of the rectal mucosa, or the squamous epithelium of the anus of pagetoid spread. Here, we report a review of perianal Paget's Disease that resulted in difficulties in borderline diagnosis of pagetoid spread, resulting in multiple therapeutic interventions.

Comparison of cold snare polypectomy for sessile serrated lesions ≥10 mm between experienced and trainee endoscopists: A propensity score matching cohort study.

Objectives: Previous studies of cold snare polypectomy (CSP) for sessile serrated lesions (SSLs) ≥10 mm were performed by experienced endoscopists, and therefore their skills might have significantly influenced results. In this study, we compared the efficacy and safety of CSP for SSLs ≥10 mm between experienced and trainee endoscopists. Methods: In a 1:1 propensity score matched retrospective cohort study, we compared the complete resection rate, en-bloc resection rate, adverse event rate, and procedure time between experienced and trainee groups. Thirteen endoscopists performed CSP, and we defined the experienced group as endoscopists with board certification from the Japan Gastroenterological Endoscopy Society. Results: We examined 616 lesions with SSLs ≥10 mm resected by CSP between February 2018 and May 2022. We excluded 61 lesions from the analysis because they had simultaneously undergone hot snare polypectomy (n = 57) or had been taken over by experienced endoscopists from trainees in the CSP procedure (n = 4). Finally, we identified 217 propensity score-matched pairs (n = 434). Between experienced and trainee groups, the results were complete resection rate (100 vs. 100%; p = 1.00), en-bloc resection rate (73.2 vs. 75.6%; p = 0.24), adverse event rate (3.2 vs. 2.8%; p = 0.77), or procedure time (6.2 vs. 5.9 min; p = 0.64). Conclusions: We have demonstrated the safety and efficacy of CSP for SSLs ≥10 mm performed by experienced and trainee endoscopists.

Endoscopic management of gastric ectopic pancreas with repeated ulcerations and bleeding: A case report.

A 25-year-old man was referred to our center for investigation of a gastric submucosal tumor and an ulcer that had developed on its oral side. Endoscopic ultrasonography findings suggested the presence of an ectopic pancreas, and treatment with an oral proton pump inhibitor was planned for the ulcer. Over the subsequent 3 years, the patient endured recurring epigastric pain and episodes of passing black stools. Emergency endoscopy revealed that the morphology of the gastric submucosal tumor had transformed into a pedunculated polyp-like morphology with a bleeding ulcer at the apex of the lesion. Endoscopic hemostasis using hemostatic forceps was performed. However, the patient continued to pass black stools. In light of the persistent symptoms and unique morphology of the lesion, endoscopic resection was attempted as a curative approach. The lesion was excised by hot snare polypectomy. Post-treatment, the patient exhibited no signs of recurrence, marking a successful resolution. Three months later, a gastroduodenal endoscopy showed that the excised site had undergone scar formation without recurrence of the lesion. This case holds significant clinical value as it demonstrates the efficacy of a minimally invasive treatment strategy in managing repeated bleeding ulcerations of an ectopic pancreas, ultimately achieving a complete cure.

Large submucosal hematoma after cold snare polypectomy for colorectal adenoma.

Cold snare polypectomy (CSP), for the treatment of colorectal polyps, has become widespread due to its low incidence of adverse events compared to that of endoscopic procedures such as endoscopic mucosal resection. However, we experienced a case of large hematoma development shortly after CSP for a colorectal adenoma despite no bleeding during the procedure. The patient underwent CSP for a 7-mm type Isp lesion in the ascending colon. She returned the following day because of hematochezia. Computed tomography showed a 70-mm, high-intensity mass in the ascending colon, consistent with the large hematoma that was detected by colonoscopy. Although the patient initially had right-sided abdominal pain, it gradually improved with conservative treatment. The hematoma decreased in size, and she was discharged 20 days after emergency admission. Although CSP can be a favorable alternative to more invasive procedures and is expected to be performed more frequently, adverse events, such as that described in this case, should be anticipated.

Gastric-type duodenal neoplasms with rapid growth: A report of two cases.

While duodenal neoplasms of the gastric phenotype are uncommon and their natural history is unknown, gastric neoplasms of gastric phenotype reportedly grow rapidly and can invade the submucosa. Several studies suggest that duodenal neoplasms of gastric phenotype might have a high risk of deep invasion and lymph node metastasis. Duodenal neoplasms of gastric phenotype might also have a high biological malignancy and likely require early treatment if detected. Here, we report two cases of intramucosal duodenal carcinoma with a gastric phenotype that grew rapidly but was successfully resected endoscopically.

Perigastric abscess caused by delayed perforation after gastric endoscopic submucosal dissection: successful conservative treatment without perforation closure: a case report.

BACKGROUND: Perigastric abscess caused by delayed perforation after endoscopic submucosal dissection is a very rare complication. In principle, delayed perforation after endoscopic submucosal dissection is treated surgically. Herein, we report a case of perigastric abscess caused by delayed perforation after gastric endoscopic submucosal dissection that was treated conservatively, without perforation closure, and in which the patient was discharged from hospital in a short period. CASE PRESENTATION: A-74-year-old Asian man was diagnosed with having early gastric cancer on follow-up endoscopy and was admitted to our hospital for endoscopic resection. Endoscopic submucosal dissection was performed without intraoperative complications. On postoperative day 2, the patient complained of a slight abdominal pain localized to the epigastric region and a small amount of melena. A computed tomography scan revealed the presence of free air in the peritoneal cavity, and a little fluid collection abutting the dorsal area of the stomach. An endoscopy examination showed a deep ulcer with the accumulation of pus, suggesting a perforation in the post-endoscopic submucosal dissection ulcer. We diagnosed a perigastric abscess, caused by delayed perforation after endoscopic submucosal dissection, and opted for conservative treatment, leaving the perforation site open to allow spontaneous drainage from the abscess into the stomach. A follow-up computed tomography scan revealed an encapsuled and localized perigastric abscess on postoperative day 5, and the disappearance of the free air and the regression of the perigastric abscess on postoperative day 7. A follow-up endoscopy examination on postoperative day 7 showed the closure of the perforation. Finally, surgery was avoided, and the patient was discharged on postoperative day 14, after a relatively short hospital stay. CONCLUSION: Regarding the treatment of perigastric abscess, caused by delayed perforation after endoscopic submucosal dissection, leaving the perforation site open to allow spontaneous drainage may shorten the conservative treatment period.

Efficacy and safety of cap-assisted endoscopic mucosal resection for superficial duodenal epithelial neoplasia ≤ 10 mm.

Background and study aims Endoscopic treatment strategies for small superficial duodenal epithelial neoplasia (SDET) have not been established, and the R0 resection rates of all previously reported endoscopic techniques are somewhat low. Furthermore, no reports of cap-assisted endoscopic mucosal resection (EMRC), which is reportedly associated with a relatively high R0 resection rate, have been evaluated in sufficient numbers of patients. Therefore, we assessed the efficacy and safety of EMRC for SDETs ≤ 10 mm in a retrospective cohort study. Patients and methods We examined a prospectively maintained database and identified 248 consecutive patients (248 lesions) who had undergone endoscopic resection for SDETs ≤ 10 mm between January 2017 and June 2022. Our treatment strategy was consistent, with EMRC indicated for all SDETs ≤ 10 mm without non-lifting signs. The primary endpoint was the R0 resection rate. Results Overall, 20 lesions had non-lifting signs and were selected for endoscopic submucosal dissection, while the remaining 228 lesions were treated with EMRC. As a result of EMRC, the median tumor size was 5 mm, and the mean procedure time was 5 minutes. Most of the lesions (89.2%) were located in the descending part. The R0 resection rate was 97.4% (222/228 cases), and the en bloc resection rate was 99.6%. Only seven patients(3.1%) experienced adverse events (6 patients, delayed bleeding; 1 patient, acute pancreatitis), which were successfully managed without surgical intervention. Furthermore, no recurrences were observed. Conclusions We have demonstrated that EMRC is an effective and safe treatment for SDETs ≤ 10 mm that do not have non-lifting signs.

Early gastric mixed neuroendocrine-non-neuroendocrine neoplasms with endoscopic findings of neuroendocrine cell carcinoma components exposed on the mucosal surface: a case report.

BACKGROUND: Gastric mixed neuroendocrine-non-neuroendocrine neoplasms are rare malignant tumors. The lack of specific findings makes it difficult to diagnose endoscopically. We report the case of early gastric mixed neuroendocrine-non-neuroendocrine neoplasms treated by endoscopic submucosal dissection. CASE PRESENTATION: An 81-year-old Japanese female underwent esophagogastroduodenoscopy for screening and was treated with endoscopic submucosal dissection for the diagnosis of early gastric cancer. Histopathologically, the lesion was diagnosed as mixed neuroendocrine-non-neuroendocrine neoplasms (tubular adenocarcinoma 2 60%, endocrine cell carcinoma 40%), pT1b(submucosa (SM) 900 µm), pUL(-), Ly(+), v(-), pHM0, pVM0. After additional surgical resection without adjuvant chemotherapy, she has had no recurrences or metastases for 3 years. CONCLUSIONS: Comparing narrow-band imaging magnified endoscopic findings with pathological findings, the depressed area with a lack of surface structure was consistent with the neuroendocrine cell carcinoma component, while narrow-band imaging magnification findings showed non-network vessels. In this case, we examined endoscopic findings of early stage mixed neuroendocrine-non-neuroendocrine neoplasms in detail and compared it with the pathological findings. We believe that these endoscopic findings contribute to the diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasms and can lead to its early detection.

Cross-term selective, two-pulse correlation measurements by phase-shifted parallel modulation for analysis of a multi-photon process.

We propose a new modulation technique for phase-sensitive detection to extract a cross-term signal appearing in multi-pulse experiments and demonstrate the selective detection of cross-term signal on two-pulse correlation measurements. This modulation technique can be widely applied to the selective detection in multi-beam laser experiments such as two-pulse correlation, auto-correlation, and double-resonance experiments, because the selectivity can be realized by using a conventional single-frequency mechanical chopper and 2f phase-sensitive detection. The effectiveness of the proposed technique was confirmed by two-pulse correlation measurements of two-photon-excited fluorescence from rhodamine 6G. In addition to the selective observation of a correlation peak, the technique succeeded in observing a weak correlation background. By combining asymmetric, two-pulse correlation measurements with the proposed technique, it was clarified that the background was produced by a three-photon process and assigned to fluorescence depletion caused by an up-conversion process. The results indicate that the cross-term selective, two-pulse correlation method that is based on the phase-shifted parallel modulation technique is powerful tool to find and analyze a high-order optical event buried in a low-order optical event.

Extraction of terminal ileal lipomas to cecum can facilitate endoscopic resection: A case series with video.

Large ileal lipomas over 2 cm can cause symptoms, that may require a resection. Due to the narrow lumen and thin walls of the ileum, endoscopic treatments can have a high risk of adverse events and require technical expertise, thus surgical resection is currently the mainstay of treatment. To overcome the technical challenges, we developed a novel method to endoscopically resect terminal ileal lipomas. The technique involves extracting the lesion into the cecum, which creates sufficient space to maneuver, and a better field of view. The lipoma is resected with endoscopic mucosal resection or endoscopic submucosal dissection. The appearance of the lipoma protruding out of the ileocecal valve resembles that of a tongue sticking out of the mouth, thus we named this the "tongue out technique". To assess the technical feasibility of this method, we retrospectively analyzed seven cases of terminal ileal lipoma that were endoscopically resected using the "tongue out technique" at NTT Medical Center Tokyo between January 2017 and October 2023. Technical success was 100% and en bloc resection was achieved in all cases. The median size was 31 (14-55) mm. Three cases were resected with endoscopic mucosal resection while endoscopic submucosal dissection was performed on the other four cases. There was one case of delayed post-endoscopic mucosal resection bleeding, which was caused by clip dislodgement. There were no perforations. No recurrence of the lipoma or associated symptoms have been observed. This new technique can allow more ileal lipomas to be treated with minimally invasive and organ-preserving endoscopic procedures.