Case of needle tract seeding during preoperative neoadjuvant chemotherapy for resectable pancreatic cancer

Reports of needle tract seeding (NTS) as a complication of endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) have been increasing. To date, most of the reported cases of NTS have been diagnosed during the postoperative follow‐up period. Herein, we report a case of NTS that occurred during preoperative neoadjuvant chemotherapy after EUS‐FNA for resectable pancreatic cancer. The patient underwent transgastric EUS‐FNA for a pancreatic tail tumor. He was diagnosed as having resectable pancreatic cancer and received preoperative neoadjuvant chemotherapy. After completion of the chemotherapy, computed tomography showed a thick‐walled cyst‐like structure appearing between the pancreas and the gastric wall. Combined resection revealed adenocarcinoma invasion into the cyst‐like structure. Based on the clinical course, and surgical and pathological findings, the condition was diagnosed as NTS. It is thus crucial that after EUS‐FNA, a detailed review of the imaging findings be conducted in the preoperative period. If adhesions between the stomach and the pancreas are observed after transgastric EUS‐FNA, combined resection of the gastric wall should be considered.

Initial drainage‐related prognostic factors for perihilar cholangiocarcinoma: A single‐center retrospective study

Objectives

Perihilar cholangiocarcinoma (PCC) is a complex disorder involving the hepatic hilum. Multiple endoscopic retrograde cholangiopancreatography sessions are necessary for diagnosis and treatment with underlying cholangitis risk. Our aim is to clarify the initial‐drainage‐related prognostic factors of PCC.

Methods

This study was a single‐center retrospective study. A total of 104 consecutive patients diagnosed with PCC from January 2010 to February 2020 were enrolled. We defined the diagnostic period as the time between the first biliary drainage attempt and the final drainage when treatment, including surgery or chemotherapy, was started. We focused on this initial period and analyzed the endoscopy‐related factors that affected mortality.

Results

Overall survival of all PCC patients was 599 days. Overall survival of surgically treated patients and unresectable patients were 893 days and 512 days, respectively. In 48 surgically treated patients, drainage‐related cholangitis within the diagnostic period, defined as new cholangitis that occurred after the first biliary drainage attempt, worsened overall survival from 1460 days to 607 days. Endoscopic sphincterotomy, the first drainage method other than endoscopic nasobiliary drainage, and four or more endoscopic retrograde cholangiopancreatography sessions were risk factors for drainage‐related cholangitis. Drainage‐related cholangitis increased pathological lymph node metastasis. Percutaneous transhepatic biliary drainage as final drainage was the only prognostic factor in unresectable chemotherapy‐treated patients.

Conclusions

Drainage‐related cholangitis worsened the prognosis in PCC patients who underwent surgery. Appropriate endoscopic retrograde cholangiopancreatography strategies, especially during the diagnostic period, are of great importance in PCC.

Advancing Nitinol: From heat treatment to surface functionalization for nickel–titanium (NiTi) instruments in endodontics

Nickel-titanium (NiTi) alloy has been extensively researched in endodontics, particularly in cleaning and shaping the root canal system. Research advances have primarily focused on the design, shape, and geometry of the NiTi files as well as metallurgy and mechanical properties. So far, extensive investigations have been made surrounding surface and thermomechanical treatments, however, limited work has been done in the realm of surface functionalization to augment its performance in endodontics. This review summarizes the unique characteristics, current use, and latest developments in thermomechanically treated NiTi endodontic files. It discusses recent improvements in nano-engineering and the possibility of customizing the NiTi file surface for added functionalization. Whilst clinical translation of this technology has yet to be fully realized, future research direction will lie in the use of nanotechnology.

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Nitinol (Nickel Titanium alloy) is widely used to clean/shape root canal system in endodontics.

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To enhance its performance, various thermo-mechanical and nano-engineering modifications have been performed.

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This comprehensive review summarizes the latest advances and future trends relating to functionalized NiTi endodontic files.

Pronounced temporal changes in soil microbial community and nitrogen transformation caused by benzalkonium chloride

As one typical cationic disinfectant, quaternary ammonium compounds (QACs) were approved for surface disinfection in the coronavirus disease 2019 pandemic and then unintentionally or intentionally released into the surrounding environment. Concerningly, it is still unclear how the soil microbial community succession happens and the nitrogen (N) cycling processes alter when exposed to QACs. In this study, one common QAC (benzalkonium chloride (BAC) was selected as the target contaminant, and its effects on the temporal changes in soil microbial community structure and nitrogen transformation processes were determined by qPCR and 16S rRNA sequencing-based methods. The results showed that the aerobic microbial degradation of BAC in the two different soils followed first-order kinetics with a half-life (4.92 vs. 17.33 days) highly dependent on the properties of the soil. BAC activated the abundance of N fixation gene (nifH) and nitrification genes (AOA and AOB) in the soil and inhibited that of denitrification gene (narG). BAC exposure resulted in the decrease of the alpha diversity of soil microbial community and the enrichment of Crenarchaeota and Proteobacteria. This study demonstrates that BAC degradation is accompanied by changes in soil microbial community structure and N transformation capacity.

Specification testing for ordinary differential equation models with fixed design and applications to COVID-19 epidemic models

Checking the models about the ongoing Coronavirus Disease 2019 (COVID-19) pandemic is an important issue. Some famous ordinary differential equation (ODE) models, such as the SIR and SEIR models have been used to describe and predict the epidemic trend. Still, in many cases, only part of the equations can be observed. A test is suggested to check possibly partially observed ODE models with a fixed design sampling scheme. The asymptotic properties of the test under the null, global and local alternative hypotheses are presented. Two new propositions about U-statistics with varying kernels based on independent but non-identical data are derived as essential tools. Some simulation studies are conducted to examine the performances of the test. Based on the available public data, it is found that the SEIR model, for modeling the data of COVID-19 infective cases in certain periods in Japan and Algeria, respectively, maybe not be appropriate by applying the proposed test.

Delayed endoscopic necrosectomy improves hospital length of stay and reduces endoscopic interventions in patients with symptomatic walled‐off necrosis

Objectives

Advancements in the endoscopic management of walled‐off necrosis using lumen apposing metal stents have improved outcomes over its surgical and percutaneous alternatives. The ideal procedural technique and timing of direct endoscopic necrosectomy (DEN) have yet to be clarified.

Methods

From November 2015 to June 2021, a retrospective comparative cohort analysis was performed comparing clinical outcomes for patients undergoing immediate DEN (iDEN) versus delayed DEN (dDEN). Subgroups were identified based on the quantification of necrosis. Wilcoxon two‐sample tests were used to compare continuous variables and Fisher's exact test was used to compare categorical variables.

Results

A total of 80 patients underwent DEN for management of walled‐off necrosis (iDEN = 43, dDEN = 37). Technical success was achieved in all patients. Clinical success was seen in 39 (91%) patients in the iDEN group and 34 (92%) in the dDEN group. Amongst iDEN patients, the mean number of necrosectomies was 2.5 (standard deviation [SD] 1.4) in comparison to 1.5 (SD 1.0) for dDEN (p‐value = 0.0011). The median index hospital length of stay was longer with iDEN than dDEN (7.5 days vs. 3.0 days respectively, p‐value = 0.010). Subgroup analysis was performed based on the percentage of necrosis (<25% vs. >25% necrosis). iDEN was associated with more necrosectomies than dDEN regardless of the percentage of necrosis (p = 0.017 and 0.0067, respectively).

Conclusion

Patients undergoing dDEN had a shorter index hospital stay and fewer necrosectomies than iDEN. The large diameter of lumen apposing metal stents permits adequate drainage allowing a less aggressive approach thereby improving clinical outcomes and avoiding unnecessary interventions.

A case report of olmesartan‐associated sprue‐like enteropathy: Diagnosis and healing confirmed by capsule endoscopy

Herein, we describe a case of olmesartan‐related sprue‐like enteropathy in which improvement in villous atrophy was confirmed by small‐bowel capsule endoscopy (CE). We successfully treated a 66‐year‐old man with a chief complaint of loose diarrhea. The patient had persistent watery diarrhea 10 times a day and experienced a weight loss of 9 kg in 3 months. An abdominal computed tomography scan showed fluid retention in the small intestine. Blood test results revealed no inflammatory reaction. Esophagogastroduodenoscopy detected villous atrophy in the stomach and duodenum. Moreover, small‐bowel CE showed villous atrophy in about two‐thirds of the small intestine. Based on other examinations, hyperthyroidism, intestinal tuberculosis, intestinal amyloidosis, and intestinal malignant lymphoma were ruled out. Therefore, the patient was suspected of having an olmesartan‐related sprue‐like disease. Early after discontinuation of medication, diarrhea symptoms improved, and a repeat CE indicated improvements in small intestinal villous atrophy. Since the patient had been administered olmesartan for a long time and CE showed villous atrophy throughout the small bowel, we suspected him of having the olmesartan‐associated sprue‐like disease. The findings of gastric mucosa atrophy on esophagogastroduodenoscopy may lead to an early diagnosis of this disease. Olmesartan‐related sprue‐like enteropathy should be considered as a differential diagnosis in patients with chronic severe watery diarrhea.

Diffuse intestinal ulcerations: Diagnostic challenge in a patient with complicated celiac disease

A 48‐year‐old female patient presented with longstanding unrecognized celiac disease (CD), a family history of CD, and a short duration of alarming symptoms. The diagnostic evaluation revealed the concomitant presence of small and large bowel ulcers raised a dilemma about differential diagnosis in her case. Pathologic examination of tissue specimens from the jejunal ulcer led to the diagnosis of enteropathy‐associated T‐cell lymphoma. In recent years, the availability of modern cross‐sectional imaging and endoscopy modalities has dramatically improved the detection and characterization of small bowel lesions. Characterization of small bowel ulcers by endoscopy and radiology imaging in a patient with suspected complicated CD (CCD) needs to be made in conjunction with all clinical factors, as there is a wide overlap of the possible etiologic factors. Enteropathy‐associated T‐cell lymphoma is a highly aggressive T‐cell lymphoma with a poor prognosis, since early diagnosis and appropriate treatment may be delayed due to nonspecific clinical and endoscopic presentation. Therefore, it is crucial to timely recognize patients with suspected CCD and properly navigate diagnostic imaging tools, acquire adequate biopsy, and perform immunophenotyping to set early diagnosis in patients with diffuse intestinal ulcers and CD.

Ex‐vivo investigation of radiofrequency ablation in pancreatic adenocarcinoma after neoadjuvant chemotherapy

Objective

Endoscopic ultrasound (US)‐guided radiofrequency ablation (RFA) has been investigated for pancreatic ductal adenocarcinoma (PDAC) but studies are limited and heterogeneous. Computed tomography (CT) scan features may predict RFA response after chemotherapy but their role is unexplored. The primary aim was to investigate the efficacy of ex‐vivo application of a dedicated RFA system at three power on surgically resected PDAC in patients who underwent neoadjuvant chemotherapy. The secondary aim was to explore the association between pre‐treatment CT‐based quantitative features and RFA response.

Methods

Fifteen ex‐vivo PDAC samples were treated by RFA under US control at three power groups (10, 30, and 50 W). Short axis necrosis diameter was measured by two expert blinded pathologists as the primary outcome. Two radiologists independently reviewed preoperative CT images.

Results

Eighty percent of specimens showed coagulative necrosis consisting of few millimeters: 5.7 ± 3.9 mm at 10 W, 3.7 ± 2.2 mm at 30 W, and 3.5 ± 2.4 mm at 50 W (p = 0.3), without a significant correlation between power setting and mean necrosis short axis (rho = –0.28; p = 0.30). Good agreement was seen between pathologists (k = 0.76; 95% confidence interval 0.55–0.98). Logistic regression analysis did not show associations between CT features and RFA response.

Conclusions

RFA causes histologically evident damage with coagulative necrosis of a few millimeters in 80% of ex‐vivo PDAC samples after chemotherapy and no clinical or pre‐operative CT features can predict efficacy. Power settings do not correlate with the histological ablation area. These results are of relevance when employing RFA in vivo and planning clinical trials on its role in PDAC patients.

Acute necrotic disorder of the small intestine post‐coronavirus disease‐2019 vaccination

The Pfizer‐BioNTech coronavirus disease 2019 (COVID‐19) vaccine is extensively used worldwide, and its safety has been proven. Herein, we report a case of an acute necrotic disorder in the small intestine post‐COVID‐19 vaccination. The patient developed severe abdominal pain the day after the first vaccination. Contrast‐enhanced computed tomography showed extensive ileum wall thickening and ascites. Colonoscopy revealed a ring‐shaped ulcer and stricture in the terminal ileum. Ileocecal resection was performed, and the patient did not have further episodes of a necrotic disorder in the small intestine. Although it is unknown if this event is associated with vaccination, and this occurrence also does not outweigh the efficacy and safety of the Pfizer‐BioNTech COVID‐19 vaccine, gastroenterologists need to be aware of this rare case, given its noteworthy timing.

Dynamic photoelectrical regulation of ECM protein and cellular behaviors

Dynamic regulation of cell-extracellular matrix (ECM)-material interactions is crucial for various biomedical applications. In this study, a light-activated molecular switch for the modulation of cell attachment/detachment behaviors was established on monolayer graphene (Gr)/n-type Silicon substrates (Gr/Si). Initiated by light illumination at the Gr/Si interface, pre-adsorbed proteins (bovine serum albumin, ECM proteins collagen-1, and fibronectin) underwent protonation to achieve negative charge transfer to Gr films (n-doping) through π-π interactions. This n-doping process stimulated the conformational switches of ECM proteins. The structural alterations in these ECM interactors significantly reduced the specificity of the cell surface receptor-ligand interaction (e.g., integrin recognition), leading to dynamic regulation of cell adhesion and eventual cell detachment. RNA-sequencing results revealed that the detached bone marrow mesenchymal stromal cell sheets from the Gr/Si system manifested regulated immunoregulatory properties and enhanced osteogenic differentiation, implying their potential application in bone tissue regeneration. This work not only provides a fast and feasible method for controllable cells/cell sheets harvesting but also gives new insights into the understanding of cell-ECM-material communications.

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A light-activated molecular switch for regulation of cell attachment/detachment behaviors was established on (Gr/Si) substrates.

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Light-induced charge transfer from ECM protein to Gr/Si through π-π interactions, resulting in the conformational alteration of ECM proteins.

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Structural changes in ECM weakened the binding between RGD and integrin, inducing cell detachment.

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This work provides a feasible method for cell harvesting and improves the understanding of cell-ECM-material communications.

A case of occult pancreaticobiliary reflux due to endoscopically confirmed relaxation of the Oddi sphincter

An otherwise healthy 45‐year‐old woman had been experiencing intermittent right upper abdominal pain for the past 1 year. Computed tomography showed pneumobilia and pancreatic duct emphysema despite a normal duodenal papilla. Magnetic resonance cholangiopancreatography and endoscopic ultrasound confirmed bile duct dilation but without a pancreaticobiliary maljunction. Duodenoscopy detected a slightly sunken, unfixed, and spontaneously enlarged duodenal papilla. During the cholangiogram, the Oddi sphincter was relaxed and the catheter could be easily inserted into the bile duct. Further, no findings suggestive of pancreaticobiliary maljunction were observed, and the contrast medium leaked spontaneously from the duodenal papilla. As biliary amylase level was high, we surmised the occurrence of occult pancreaticobiliary reflux due to relaxation of the Oddi sphincter. However, as there are no guidelines on the management of this condition, we did not offer any treatment. Nevertheless, the patient continued to experience similar symptoms and was retested 1 year later with similar results. As occult pancreaticobiliary reflux was reconfirmed, we suggested that the patient undergo laparoscopic extrahepatic bile duct resection and cholecystectomy, which is the standard treatment for pancreaticobiliary maljunction. Pathological evaluation revealed fibrous thickening of the bile duct wall and chronic cholecystitis, which are typical findings of pancreaticobiliary reflux. Even though pancreaticobiliary reflux is mainly observed in pancreaticobiliary maljunction, it has also been reported in normal patients. Here, we describe a novel mechanism of pancreaticobiliary reflux, namely, a relaxed or defective Oddi sphincter.

Massive bleeding from a duodenal ulcer in a child with influenza infection: A case report of endoscopic findings

Gastrointestinal bleeding or perforation following influenza infection is rare. We encountered a pediatric case of hemorrhagic duodenal ulcer following influenza A infection. The patient was a 1‐year and 4‐month‐old boy who was diagnosed with influenza A infection and treated with laninamivir octanoate. After inhalation, he had diarrhea, poor appetite, and melena. The next day, he had hematochezia and developed hemorrhagic shock. Contrast‐enhanced computed tomography showed extravasation in the descending part of the duodenum. Esophagogastroduodenoscopy revealed spurting bleeding from a Dieulafoy's lesion on the oral side of the major papilla, and he underwent hemostasis by clipping. From the bulb to the descending part of the duodenum, the mucosa appeared atrophic with spotty redness on the circular folds and multiple and irregularly shaped erosions. Almost all mucosal lesions had healed by the eighth day, and he was monitored as an outpatient for more than one year without re‐bleeding. Intestinal ischemia, viral invasion, and drug reaction of laninamivir octanoate may be involved in duodenal mucosal injury. Acute duodenal ulcers may occur in children with influenza infection, especially young children.

The effect of fear and situational motivation on online information avoidance: The case of COVID-19

During the COVID-19 pandemic, a plethora of online sources for information and news dissemination have emerged. Extant research suggests that very quickly, individuals become disinterested and begin avoiding the information. In this study, we investigate how an individual's fear and situational motivation impact Online Information Avoidance. Using the self-determination theory and information avoidance theories, we argue that fear and external regulation are associated with increased Online Information Avoidance. We also argue that intrinsic motivation and identified regulation are associated with a decrease in Online Information Avoidance. Our findings suggest that fear, intrinsic motivation, and external regulation drive Online Information Avoidance, where intrinsic motivation is the most significant driver. We also found that identified regulation is a crucial inhibitor of Online Information Avoidance. While focusing on COVID-19, our study contributes to the broader information systems research literature and specifically to the information avoidance literature during a pandemic or a prolonged crisis. Our study's findings will be useful for governments, health organizations, and communities that utilize online platforms, forums, and related outlets to reach larger audiences for disseminating pertinent information and recommendations during a crisis.

Evaluation of the effect of COVID-19 mandated shift to virtual teaching on medical students' performance at King Khalid University, Abha

Objectives

The rapid spread of the COVID-19 pandemic required populations in most parts of the world to take drastic precautions. Face-to-face teachings were suspended, and the teaching and learning process was shifted to the virtual mode. This was a formidable challenge for students, teachers, parents, guardians, and academic administrators. The main objective of this study was to assess the impact of the shift to virtual mode on medical students' academic performance in general and systemic pathology courses.

Methods

The grades achieved in a quiz and practical test taken before the shift to virtual classes were compared to another quiz and practical exam taken by the same groups of students after several weeks of virtual teaching. The paired t-test was conducted to test the hypotheses, and SPSS software was used for data analyses. A short electronic survey was designed and sent to the targeted students (N = 103). The targeted students were also surveyed to understand their experience with e-learning during this time.

Results

In total, 60% of the students reported their e-learning experience as valuable, and 84% prefer to have e-learning as part of the teaching and learning process even after normalcy is restored. The students' performance in the post-virtual tests was significantly better than that in the pre-virtual tests.

Conclusion

The virtual learning format was well received by the students and influenced their academic outcomes. Institutes should provide training sessions for staff and students to address potential education drawbacks and provide modern educational technologies and simulation labs to enhance the educational systems.

Setting up a three‐stage pre‐endoscopy triage during the coronavirus disease 2019 pandemic: A multicenter observational study

Objectives

Between May and July 2021, the coronavirus disease 2019 (COVID‐19) pandemic led to a sharp surge in community transmission in Taiwan. We present a three‐stage restructuring process of pre‐endoscopy triage at the beginning of the pandemic, which can support urgent endoscopic procedures while protecting endoscopy staff.

Methods

The pre‐endoscopy triage framework was set up with three checkpoints at the hospital entrance, outpatient department, and endoscopy unit, with a specific target patient population and screening methods. Relevant data included the number of endoscopic procedures performed, outpatient department visits, and performing screening methods such as temperature measurement, travel, occupation, contact, and clustering history checking, polymerase chain reaction assay, and rapid antigen test.

Results

Forehead temperature measurement and verification of travel, occupation, contact, and clustering history provided rapid, easy, and early mass screening of symptomatic patients at the hospital entrance. During the pandemic, outpatient department visits and endoscopic procedures decreased by 37% and 64%, respectively. The pre‐endoscopy screening methods used displayed regional variations in COVID‐19 prevalence. Among 16 endoscopy units with a community prevalence of ≥ 31.04 cases per 100,000 residents, 12 (75%) used polymerase chain reaction assay and four (25%) used rapid antigen test to identify asymptomatic patients before endoscopy. Of 6540 pre‐endoscopy screening patients, 15 (0.23%) tested positive by laboratory testing. No endoscopy‐related nosocomial COVID‐19 infections were reported during the pandemic.

Conclusions

We present a three‐stage pre‐endoscopy triage based on the local laboratory capacity, medical resources, and community prevalence. These measures could be useful during the COVID‐19 pandemic.

Incarceration of a colonoscope in an inguinal hernia: A report of two cases

We report two cases of the rare complication of a colonoscope incarcerated in an inguinal hernia. The first patient was a 73‐year‐old man in whom a colonoscope was incarcerated in a left inguinal hernia on attempted withdrawal. The incarcerated colonoscope was successfully reduced manually under fluoroscopic guidance. The hernia was subsequently repaired using an extraperitoneal approach followed by a successful colonoscopy. The second patient was a 74‐year‐old man in whom the colonoscope became incarcerated in a left inguinal hernia on insertion. Similar to the first case, the colonoscope was manually reduced under fluoroscopy and the entire colonoscopy was then uneventfully performed. An advanced sigmoid cancer was identified and treated with sigmoidectomy. The hernia resolved after this operation. When a colonoscope becomes incarcerated in an inguinal hernia, the manual reduction should be attempted. Subsequent colonoscopy can be safely performed under certain circumstances.

3D printing of conch-like scaffolds for guiding cell migration and directional bone growth

Regeneration of severe bone defects remains an enormous challenge in clinic. Developing regenerative scaffolds to directionally guide bone growth is a potential strategy to overcome this hurdle. Conch, an interesting creature widely spreading in ocean, has tough spiral shell that can continuously grow along the spiral direction. Herein, inspired by the physiological features of conches, a conch-like (CL) scaffold based on β-TCP bioceramic material was successfully prepared for guiding directional bone growth via digital light processing (DLP)-based 3D printing. Benefiting from the spiral structure, the CL scaffolds significantly improved cell adhesion, proliferation and osteogenic differentiation in vitro compared to the conventional 3D scaffolds. Particularly, the spiral structure in the scaffolds could efficiently induce cells to migrate from the bottom to the top of the scaffolds, which was like “cells climbing stairs”. Furthermore, the capability of guiding directional bone growth for the CL scaffolds was demonstrated by a special half-embedded femoral defects model in rabbits. The new bone tissue could consecutively grow into the protruded part of the scaffolds along the spiral cavities. This work provides a promising strategy to construct biomimetic biomaterials for guiding directional bone tissue growth, which offers a new treatment concept for severe bone defects, and even limb regeneration.

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A conch-like scaffold was firstly developed for guiding directional bone growth.

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The CL scaffolds efficiently induced cells “climbing stairs”- like-migrating.

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The CL scaffolds showed improved bioactivities benefited from the spiral structure.

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This work provided a new treatment concept for severe bone defects.

Application and usefulness of a new eight‐wire basket catheter for endoscopic extraction of small common bile duct stones: A retrospective multicenter study

Objectives

Distally located small common bile duct stones are often difficult to treat or grasp endoscopically. Therefore, multiple devices, such as baskets or balloon catheters, are frequently used in such cases. However, it is desirable to use a single device for stone extraction from the perspective of cost‐effectiveness. In this multicenter study, we evaluated the efficacy of a new eight‐wire basket catheter for extracting small (≤10 mm) common bile duct stones.

Methods

We retrospectively analyzed the records of 144 patients who underwent stone extraction using the eight‐wire basket catheter for common bile duct stones ≤10 mm. The success rate of complete stone extraction and the risk factors for the difficulty in stone extraction with the eight‐wire catheter alone were mainly evaluated.

Results

The success rate of stone extraction with the eight‐wire catheter alone was 86.1%. The final rate of complete stone extraction was 98.0%. The mean of the maximum diameter of the common bile duct and the largest stone dimension were 10.5 ± 3.5, and 5.1 ± 2.1 mm, respectively. Common bile duct diameter ≥12 mm and stone diameter ≥6 mm were identified as independent risk factors for the difficulty in stone extraction with the eight‐wire catheter alone.

Conclusions

The success rate of the new eight‐wire basket for small common bile duct stone extraction was acceptable. The device is beneficial and could be used from the start for the extraction of small stones < 6 mm.

Factors that affect the development of acute hemorrhagic rectal ulcer syndrome and rebleeding

Objectives

Acute hemorrhagic rectal ulcer syndrome (AHRUS) causes massive bleeding and often recurrent rebleeding from rectal ulcers that form immediately above the dentate line. This study aimed to determine the clinical background and risk factors contributing to rebleeding in patients with AHRUS and the most appropriate method of hemostasis treatment.

Methods

This retrospective study included 93 patients diagnosed with AHRUS at Showa University Fujigaoka Hospital, Japan, between April 2009 and November 2018. Information on clinical background factors, endoscopic findings, and hemostasis was obtained from medical records. The relationship with episodes of rebleeding was analyzed by multivariate logistic regression analysis.

Results

The median age was 79 years, and 84 patients (90%) had a performance status of grade 2 or higher. The patients had multiple background factors, with a median number of 5 per patient. The background factors could be classified into two major factors: those related to arteriosclerosis and those related to delayed wound healing.

In the multivariate analysis, significantly more rebleeding occurred in patients with active bleeding during the initial endoscopy (odds ratio 4.88, 95% confidence interval 1.80–14.46, p = 0.003); significantly less rebleeding occurred in patients for whom hemostasis was first performed by clipping (odds ratio 0.30, 95% confidence interval 0.09–0.88, p = 0.035).

Conclusions

In bedridden older individuals with poor general health, multiple combinations of arteriosclerosis‐related factors and protracted wound healing factors can induce AHRUS. We strongly recommend performing hemostasis via the clipping method on suspected bleeding points, including active bleeding sites, in AHRUS.

Linked color imaging improves the diagnostic accuracy of eosinophilic esophagitis

Objectives

To assess the usefulness of linked color imaging (LCI), a recently developed image‐enhanced endoscopy technique, in the endoscopic diagnosis of eosinophilic esophagitis (EoE).

Methods

Thirty white light images (WLIs) and 30 WLI+LCI images collected from patients with and without EoE were randomly and blindly reviewed by 10 endoscopists, including four experts (Exs) and six non‐Exs. Edema, ring, exudate furrows, and strictures were rated on the adjusted EoE endoscopic reference score; the diagnosis of EoE was assessed. Using the kappa value, inter‐ and intra‐observer agreements were analyzed among endoscopists.

Results

WLI+LCI images had a higher diagnostic accuracy for EoE than WLIs (0.85 vs. 0.70, respectively), especially in non‐Exs or endoscopists with no experience with EoE patients. Inter‐observer agreement for WLI+LCI images statistically surpassed WLIs for furrows (kappa, 0.73 vs. 0.67, respectively; p = 0.0013), stricture (kappa, 0.51 vs. 0.39, respectively; p = 0.0072), and diagnosis (kappa, 0.67 vs. 0.57, respectively; p < 0.0001) of EoE. The increase in inter‐observer agreement in WLI+LCI images allowed for a reduction in the differences between the Exs and non‐Ex endoscopists. Intra‐observer agreement for WLI+LCI images surpassed WLIs for a ring (kappa, 0.62 vs. 0.43, p = 0.0052), and a similar trend was found in exudates, furrows, and diagnosis irrespective of the Exs or non‐Exs.

Conclusions

LCI can contribute to the improvement of the endoscopic diagnosis for EoE, with “moderate” to “substantial” consistency, by enhancing the visibility of abnormal findings, leading to reduced diagnostic disparities among endoscopists.

Assessment of photodynamic therapy as a salvage treatment for local failure after chemoradiotherapy or radiotherapy for esophageal cancer in patients aged 80 years or older

Objectives

Chemoradiotherapy (CRT) or radiotherapy (RT) alone is often the treatment of choice for elderly patients with esophageal cancer with the expectation of organ preservation. However, salvage treatment remains a problem when endoscopic resection is not indicated for local failure after CRT/RT. Photodynamic therapy (PDT) is indicated for local failure after CRT/RT, but there are few reports on its efficacy and safety in elderly patients. This study aimed to assess the outcome of PDT for local failure after CRT/RT for esophageal cancer in elderly patients.

Methods

This retrospective single‐center study included 42 patients who first underwent PDT between April 2013 and June 2021. Patients aged ≥80 and <80 years were classified into the elderly and nonelderly groups, respectively. Local complete response rate, overall survival, progression‐free survival, and incidence of adverse events related to PDT were compared retrospectively between the groups.

Results

The local complete response rate was 93.3% in the elderly group and 85.7 in the non‐elderly group. The 2‐year overall survival rate was 68.6% and 72.5%, and the 2‐year progression‐free survival rate was 49.5% and 70.0% in the elderly and nonelderly groups, respectively. There was no significant difference in any of these outcomes between the groups. In terms of adverse events, pneumonia and delirium tended to occur more frequently in the elderly group, but there were no serious adverse events in either group.

Conclusion

The outcome of salvage PDT in the local control was comparable between the elderly and nonelderly patients for local failure after CRT/RT for esophageal cancer.

Potential significance of uncovered self‐expandable metal stents for distal malignant biliary obstruction: A propensity score‐adjusted competing risk regression analysis

Objectives

Selection criteria for self‐expandable metal stents (SEMSs) with or without cover during palliative treatment of distal malignant biliary obstruction (DMBO) remain unclear. We evaluated factors associated with time to recurrent biliary obstruction (TRBO) in fully covered SEMSs (FCSEMSs) and uncovered SEMSs (UCSEMSs).

Methods

We retrospectively analyzed consecutive patients with DMBO who received a SEMS. TRBO was determined using the Kaplan–Meier analysis, and complications were compared between the FCSEMS and UCSEMS groups. After TRBO‐associated factors were extracted using multivariate competing‐risks regression (CRR), propensity score‐adjusted CRRs were performed to verify their robustness.

Results

There were 180 patients (66 FCSEMSs and 114 UCSEMSs) enrolled in this study. There was no significant difference between median TRBO in the FCSEMS and UCSEMS groups (275 vs. 255 days, p = 0.67). Complications were more frequent in the FCSEMS than UCSEMS group (21.2% vs. 8.8%; p = 0.023). Multivariate CRR for TRBO‐associated factors revealed that “pancreatic ductal carcinoma (PDAC) treated with UCSEMS” was the only independent predictor of TRBO (p = 0.03). Similarly, the propensity score‐adjusted CRRs showed no significant difference in TRBO in “FCSEMS” vs “UCSEMS” (p = 0.96); however, there was a significant difference in “PDAC using UCSEMS” vs “other” (p = 0.043). In the palliative care group including any DMBO without chemotherapy, the first quartile of the TRBO of UCSEMS was 100 days.

Conclusions

UCSEMSs are a possible option for both patients with DMBO arising from PDAC and for patients with any DMBO receiving palliative care who should avoid SEMS‐related complications.

A rare case of inflammatory polyp in the common bile duct with cholangitis

The diagnosis of bile duct tumors can be difficult at times. A transpapillary bile duct biopsy findings with endoscopic retrograde cholangiopancreatography sometimes contradict diagnostic imaging findings. In bile duct tumors, inflammatory polyps in the extrahepatic bile duct are relatively rare with extrahepatic cholangitis. The disease's clinical relevance, including its natural history and prognosis, is not always clear. We show here a rare case of an inflammatory polyp in the common bile duct. A 69‐year‐old woman with abdominal pain was diagnosed with cholangitis. The findings of contrast‐enhanced computed tomography and magnetic resonance cholangiopancreatography suggested that she had extrahepatic cholangiocarcinoma. The examination and therapy of cholangitis were performed by endoscopic retrograde cholangiopancreatography. The cholangiography revealed a suspected tumor in the hilar bile duct with some common bile duct stones. Then, after endoscopic sphincterotomy to remove tiny common bile duct stones, further detailed examinations were performed at the same time using an oral cholangioscope revealed a papillary raised lesion with a somewhat white surface in the bile duct; a biopsy was conducted on the same spot, and epithelial cells with mild atypia appeared in the shape of a papilla. Since the malignant tumor or the intraductal papillary neoplasm of the bile duct could not be ruled out, extrahepatic bile duct resection was conducted with the patient's informed consent. Bile duct inflammatory polyp was the histopathological diagnosis.

Evaluation of the effect of fish oil in the prevention of pressure ulcers in patients admitted to the intensive care unit

Introduction

Today, the anti-inflammatory property of fish oil is used to heal wounds, but this property has not been investigated to prevent the occurrence of pressure ulcers. So the research team decided to evaluate this feature as well.

Materials and methods

This clinical trial study was performed on 102 patients admitted to the intensive care unit located at Besat Hospital in 2020. Samples were assigned to three groups control, placebo, and intervention using permutation blocks. Before the intervention, the questionnaire of demographic and clinical variables, level of consciousness, Braden scale, and short nutritional status questionnaire was completed by the main researcher. In the intervention group, in addition to routine care, 2 cc of fish oil was gently rubbed into the sacrum once a day for 5 days. The same intervention was repeated in the placebo group, with the difference that soybean oil was used instead of fish oil, and the control group received only the usual care. The daily evaluation of pressure ulcers by one of the ICU nurses lasted up to 6 days.

Results

The results showed that there was a significant difference in the incidence of pressure ulcers in the three groups (P = 0.043). The risk of pressure ulcers in the control group was 11.9 and 2.7 times higher than the fish oil group and placebo group (P = 0.023) & (P = 0.132).

Conclusion

The use of topical fish oil can be effective in preventing pressure ulcers.

Efficacy and safety of endoscopic stent placement for afferent loop obstruction using a short double‐balloon endoscopy

Background

Methods

Results

Conclusions

Palliative stenting for malignant colorectal stenosis in the elderly

Objectives

Self‐expandable metal stents are widely used for the treatment of malignant colorectal stenosis (MCS). In elderly individuals with MCS, self‐expandable metal stents are often used as a palliative treatment, but prophylactic stent placement is not recommended. We investigated the efficacy and safety of self‐expandable metal stents for the elderly in a palliative setting, specifically in a prophylactic setting.

Methods

Elderly patients with MCS who received a palliative stent (the stent group) or palliative stoma (the stoma group) were retrospectively enrolled between April 2017 and June 2022, and the prognosis and complication rates were assessed. Additionally, patients in the stent group were divided into symptomatic and asymptomatic subgroups, and prognosis, stent patency, and complication rates were evaluated.

Results

During the study period, 31 patients with a mean age of 85.4 years and 12 patients with a mean age of 82.0 years were enrolled in the stent and stoma groups, respectively. While overall survival and complication rates were comparable, the length of hospital stay was significantly shorter in the stent group. Of the 31 patients in the stent group, 16 asymptomatic patients received prophylactic stenting, which was not associated with increased complication rates.

Conclusions

Palliative stents for MCS appear to be effective and safe even in the elderly, and thus, prophylactic stents can be considered for asymptomatic patients.

The impact of early‐stage COVID‐19 pandemic on the diagnosis and treatment of gastric cancer: A cross‐sectional study using a large‐scale cancer registry in Hiroshima, Japan

Background

After the confirmation of coronavirus infection in Japan, a behavioral change caused people and physicians to refrain from visiting hospitals or undergoing examinations. This study aimed to assess how the trend of diagnosis in gastric cancers changed, and how it affected the therapeutic strategies and the interval from diagnosis to treatment during the COVID‐19 pandemic.

Methods

We use 15 cancer‐designated hospitals’ registries in Hiroshima, Japan. The target period was March to December 2020, and the same period in 2019 was set as the control period. The monthly mean of diagnoses and the interval from diagnosis to treatment were compared overall and separately by age, treatment procedure, diagnostic process, and clinical stage.

Result

In 2020, the monthly mean (standard deviation [SD]) of patients was 192.2 (29.9), a significant 20.1% decrease from 240.7 (20.7) in 2019 due to older age and curative treatment groups. By reason for performing endoscopy, the change rate in cancer screening, endoscopic follow‐up, and symptomatic status were ‐27.0%, ‐18.0%, and ‐17.3%, respectively. Meanwhile, the interval (days) from diagnosis to treatment (SD) was 37.8 (26.5) in 2020, significantly shorter than 46 (31.5) in 2019.

Conclusion

From 2019 to 2020, we observed a significant decrease in the diagnosis of curable early‐stage gastric cancer and treatments, although the interval from diagnosis to treatment decreased. This study suggests that cancer screening played a significant role in the decline in cancer diagnosis that occurred during the COVID‐19 pandemic. Even under COVID‐19 pandemic conditions, there should be an awareness of cancer screening and endoscopic follow‐up.

Endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma in patients with cirrhosis and esophageal varices

Endoscopic submucosal dissection (ESD) has become the standard treatment for superficial esophageal squamous cell carcinoma (SESCC). However, the treatment strategy for SESCC complicated by esophageal varices (EVs) has not been established. We report two cases of SESCC in patients with alcoholic cirrhosis complicated by EVs who underwent ESD. Case 1 presented with EVs on the anal side of the SESCC, and endoscopic variceal ligation (EVL) was performed before ESD. After EVL, the SESCC was successfully treated by ESD without any adverse events. Case 2 presented EVs from the anal side of the SESCC to the submucosa just below the SESCC. Then, EVL and endoscopic injection sclerotherapy with polidocanol were performed before ESD. However, ESD was not completed because of severe bleeding by uncontrolled blood flow below and around the SESCC. Bleeding during ESD was controlled in case 1, but not in case 2.

Piezoresistive MXene/Silk fibroin nanocomposite hydrogel for accelerating bone regeneration by Re-establishing electrical microenvironment

The electrical microenvironment plays an important role in bone repair. However, the underlying mechanism by which electrical stimulation (ES) promotes bone regeneration remains unclear, limiting the design of bone microenvironment–specific electroactive materials. Herein, by simple co-incubation in aqueous suspensions at physiological temperatures, biocompatible regenerated silk fibroin (RSF) is found to assemble into nanofibrils with a β-sheet structure on MXene nanosheets, which has been reported to inhibit the restacking and oxidation of MXene. An electroactive hydrogel based on RSF and bioencapsulated MXene is thus prepared to promote efficient bone regeneration. This MXene/RSF hydrogel also acts as a piezoresistive pressure transducer, which can potentially be utilized to monitor the electrophysiological microenvironment. RNA sequencing is performed to explore the underlying mechanisms, which can activate Ca²⁺/CALM signaling in favor of the direct osteogenesis process. ES is found to facilitate indirect osteogenesis by promoting the polarization of M2 macrophages, as well as stimulating the neogenesis and migration of endotheliocytes. Consistent improvements in bone regeneration and angiogenesis are observed with MXene/RSF hydrogels under ES in vivo. Collectively, the MXene/RSF hydrogel provides a distinctive and promising strategy for promoting direct osteogenesis, regulating immune microenvironment and neovascularization under ES, leading to re-establish electrical microenvironment for bone regeneration.

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MXene nanosheets could direct the selective growth of silk nanofibrils.

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Prepared MXene/RSF hydrogel exhibited good conductivity and sensing ability.

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The electroactive hydrogel could promote osteogenic differentiation of BMSCs by activating the Ca²⁺/CALM signaling pathway.

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The conductive system created an osteoblast–macrophage–endotheliocyte virtuous circle for bone microenvironment.

Predictive model for bleeding after gastric submucosal dissection before and after guidelines: A single‐center retrospective study

Objectives

In July 2017, supplementary guidelines on anticoagulants, including direct oral anticoagulants, were published in Japan. We investigated the changes in endoscopic submucosal dissection (ESD) of gastric mucosal lesions after the publication of the supplement, examined the risk factors, and developed a predictive model for post‐ESD bleeding.

Methods

We included 2272 gastric ESD cases from our hospital between May 2003 and June 2021 and classified them into two groups: 1789 cases before and 483 after the publication of the supplementary guidelines. A predictive model for post‐ESD bleeding was developed using the pre‐publication cohort data.

Results

The proportion of patients receiving warfarin decreased (5.0% vs. 1.4%) and those receiving direct oral anticoagulants increased (1.2% vs. 6.8%) after the publication of the supplementary guidelines. Post‐ESD bleeding occurred in 61 patients, but there was no significant difference in the bleeding rate between the groups (50 [2.8%] vs. 11 [2.3%] patients, respectively). Five risk factors (number of antithrombotic agents, dialysis, heparin replacement, resection specimen size, and procedure time) were identified for model development. The C‐statistic for the model and post‐publication cohorts were 0.83 and 0.72, respectively. In the model, each risk factor for postoperative bleeding was scored, and the risk was classified into three levels according to the total score. Bleeding rates at low, intermediate, and high risks were 1.6%, 10.3%, and 38.9%, respectively.

Conclusion

Despite changes in patient characteristics and clinical practice regarding ESD before and after the publication of the supplementary guidelines, we could still develop a simple and useful predictive model.

Electrosurgical knife with the water‐jet function of tip‐type during endoscopic treatment injection

Objectives

This study aimed to objectively evaluate the water‐jet‐functioned electrosurgical knife injection performances in a desktop experiment.

Methods

Five types of water‐jet‐functioned electrosurgical knives, including two injection styles of sheath‐type (A: DualKnife J, KD‐655L; B: FlushKnife, DK2620‐J‐B20S; C: Splash M‐Knife, DN‐D2718B; D: ISSEN, SN1650‐20) and tip‐type (E: ORISE ProKnife, M00519361) were evaluated. These knives were compared with an injection needle (Control: SuperGrip 25G) as a control. The injection speed under constant pressure and the injection efficiency for each knife against prepared porcine stomach mucosa were evaluated. The additional clear gel injections using an injection needle were observed using an indigo blue‐colored gel to evaluate the difference between the locations of water‐jet holes.

Results

Four types of knives, except for A, showed significantly higher water‐jet speeds (A: 0.79 ± 0.03 g/20 s, B: 2.56 ± 0.05 g/20 s, C: 3.09 ± 0.06 g/20 s, D: 2.86 ± 0.05 g/20 s, and E: 1.79 ± 0.03 g/20 s) compared to that of the control (1.21 ± 0.03 g/20 s). Meanwhile, significantly higher efficacy of injection was found in the tip‐type water‐jet function knife, second to the injection needle (Control: 37.2% ± 35.5%, A: 20.9% ± 20.2%, B: 1.1% ± 2.2%, C: 6.2% ± 12.6%, D: 12.5% ± 15.6%, and E: 33.3% ± 32.2%). An additional injection experiment revealed that the injection with a piercing tip into the gel could achieve sufficient additional injection inside the stacked clear gel.

Conclusions

The tip‐type water‐jet function electrosurgical knife is preferable for effective submucosal injection during endoscopic treatments.

Prediction of depth of invasion and lymph node metastasis in superficial pharyngeal cancer by magnifying endoscopy using the Japan Esophageal Society classification

Backgrounds

The pharynx has no muscularis mucosae, so it is unclear whether diagnostic techniques used for the esophagus can be applied to the pharynx. This study investigated the usefulness of magnifying endoscopy with narrowband imaging using the Japan Esophageal Society (JES) classification for predicting the depth of invasion and lymph node metastasis (LNM) in pharyngeal cancer.

Methods

A total of 123 superficial pharyngeal carcinoma lesions that had been observed preoperatively with magnifying endoscopy with narrowband imaging between January 2014 and June 2021 were analyzed. Predictors of subepithelial invasion (SEP) and LNM were sought based on endoscopic findings, including microvascular morphology, using the JES classification.

Results

The lesions were divided into carcinoma in situ (n = 41) and SEP (n = 82). Multivariate analysis identified B2–B3 vessels (odds ratio [OR] 6.54, 95% confidence interval [CI] 1.74–24.61, p = 0.005) and a middle/large avascular area (OR 4.15, 95% CI 1.18–14.62, p = 0.027) as independent predictors of SEP. Significant predictors of LNM were protruding type, B2–B3 vessels, middle/large avascular area, SEP, venous invasion, lymphatic invasion, and tumor thickness > 1000 μm. Median tumor thickness increased significantly in the order of B1 < B2 < B3 vessels (B1, 305 μm; B2, 1045 μm; B3, 4043 μm; p < 0.001). The LNM rates for B1, B2, and B3 vessels were 1.6% (1/63), 4.8% (2/42), and 55.6% (10/18), respectively (p < 0.001).

Conclusions

Magnifying endoscopy with narrowband imaging using the JES classification could predict the depth of invasion in superficial pharyngeal carcinoma. The JES classification may contribute to the prediction of LNM, suggesting that it could serve as an alternative to tumor thickness.

A single‐sided trans‐nasal catheter for smooth and efficient oxygen delivery can improve the safety in patients undergoing pancreato‐biliary endoscopy under intravenous sedation: A randomized trial

Background

Pancreato‐biliary endoscopic procedures often need to be performed under deep intravenous sedation. The patients are at an increased risk of respiratory depression influenced by the anatomical dead space of the upper respiratory system. We aimed to evaluate the benefit of oxygen delivery through a single‐sided trans‐nasal catheter (TC) for patients undergoing pancreato‐biliary endoscopy.

Methods

Oxygen supplementation during the procedure was provided either by insertion of a single‐sided TC or insertion of a conventional nasal catheter (NC). A prospective, single‐blind, randomized controlled study was conducted in two groups.

Results

The number of patients who indicated a decrease in the peripheral transcutaneous oxygen saturation (SpO2; desaturation) was significantly lower in the TC group than in the counterpart (8/58; 13.8% vs. 26/58; 44.8% p < 0.001). The efficient oxygen delivery in the safe range was better conserved in the TC group than in the NC one. There was no adverse effect on both groups. The maximum SpO2 while the endoscopic procedure was significantly higher in the TC group (99.7% vs. 99.3% p = 0.016) and the minimum SpO2 was also significantly higher in the same group (97.7% vs. 94.1% p < 0.0001), which meant that the efficient oxygen delivery was better maintained in TC group than the NC group.

Conclusions

A single‐sided TC placed in the pharynx in patients undergoing pancreato‐biliary endoscopy prepares a superior condition of the patients for venous sedation, maintained hyper‐oxygen saturation and a relatively higher SpO2 level to be maintained in limited conditions to reduce the dead space with acceptable tolerance, as compared to the placement of a conventional NC.

Nanodrugs alleviate acute kidney injury: Manipulate RONS at kidney

Currently, there are no clinical drugs available to treat acute kidney injury (AKI). Given the high prevalence and high mortality rate of AKI, the development of drugs to effectively treat AKI is a huge unmet medical need and a research hotspot. Although existing evidence fully demonstrates that reactive oxygen and nitrogen species (RONS) burst at the AKI site is a major contributor to AKI progression, the heterogeneity, complexity, and unique physiological structure of the kidney make most antioxidant and anti-inflammatory small molecule drugs ineffective because of the lack of kidney targeting and side effects. Recently, nanodrugs with intrinsic kidney targeting through the control of size, shape, and surface properties have opened exciting prospects for the treatment of AKI. Many antioxidant nanodrugs have emerged to address the limitations of current AKI treatments. In this review, we systematically summarized for the first time about the emerging nanodrugs that exploit the pathological and physiological features of the kidney to overcome the limitations of traditional small-molecule drugs to achieve high AKI efficacy. First, we analyzed the pathological structural characteristics of AKI and the main pathological mechanism of AKI: hypoxia, harmful substance accumulation-induced RONS burst at the renal site despite the multifactorial initiation and heterogeneity of AKI. Subsequently, we introduced the strategies used to improve renal targeting and reviewed advances of nanodrugs for AKI: nano-RONS-sacrificial agents, antioxidant nanozymes, and nanocarriers for antioxidants and anti-inflammatory drugs. These nanodrugs have demonstrated excellent therapeutic effects, such as greatly reducing oxidative stress damage, restoring renal function, and low side effects. Finally, we discussed the challenges and future directions for translating nanodrugs into clinical AKI treatment.

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AKI is a common clinical acute syndrome with high morbidity and mortality but without effective clinical drug available.

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Hypoxia and accumulation of toxic substances are key pathological features of various heterogeneous AKI.

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Excessive RONS is the core of the pathological mechanism of AKI.

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The development of nanodrugs is expected to achieve successful treatment in AKI.

Distinguishing the papilla of Vater during biliary cannulation using texture and color enhancement imaging: A pilot study

Objectives

Understanding the exact morphology of the bile duct opening is important for determining the success of bile duct cannulation. Texture and color enhancement imaging (TXI) has been reported to enhance slight changes in color tone and structure that are difficult to see with white light imaging. This study investigated whether TXI mode1 could improve papillary recognition by trainees inexperienced in endoscopic retrograde cholangiopancreatography.

Methods

We included 31 patients with naive papilla of Vater at a single institution in the study. Trainee endoscopists (n = 4) evaluated and identified the papilla according to the Inomata classification using white light imaging and TXI. The degree of agreement with the evaluation of supervising physicians (n = 4) was examined using the McNemar test.

Results

In the trainee group, the kappa coefficient agreements were κ = 0.346 and κ = 0.754 for white light imaging and TXI, respectively. When further evaluated, the separate and septal types of papilla groups showed an increased concordance rate in one of the four trainees (76.67%–96.67%, p = 0.031, respectively). Moreover, comparison for two‐group evaluation showed an increased kappa coefficient in two of four trainees (0.34–0.92, p = 0.010, 0.45–0.92, p = 0.024).

Conclusions

Observation of the duodenal papilla using TXI improved papillary differentiation and suggested the potential of TXI as a clinical tool. Further study of this method is necessary; it is expected to help reduce cannulation time and the incidence of pancreatitis.

Ion elemental-optimized layered double hydroxide nanoparticles promote chondrogenic differentiation and intervertebral disc regeneration of mesenchymal stem cells through focal adhesion signaling pathway

Chronic low back pain and dyskinesia caused by intervertebral disc degeneration (IDD) are seriously aggravated and become more prevalent with age. Current clinical treatments do not restore the biological structure and inherent function of the disc. The emergence of tissue engineering and regenerative medicine has provided new insights into the treatment of IDD. We synthesized biocompatible layered double hydroxide (LDH) nanoparticles and optimized their ion elemental compositions to promote chondrogenic differentiation of human umbilical cord mesenchymal stem cells (hUC-MSCs). The chondrogenic differentiation of LDH-treated MSCs was validated using Alcian blue staining, qPCR, and immunofluorescence analyses. LDH-pretreated hUC-MSCs were differentiated prior to transplantation into the degenerative site of a needle puncture IDD rat model. Repair and regeneration evaluated using X-ray, magnetic resonance imaging, and tissue immunostaining 4–12 weeks after transplantation showed recovery of the disc space height and integrated tissue structure. Transcriptome sequencing revealed significant regulatory roles of the extracellular matrix (ECM) and integrin receptors of focal adhesion signaling pathway in enhancing chondrogenic differentiation and thus prompting tissue regeneration. The construction of ion-specific LDH nanomaterials for in situ intervertebral disc regeneration through the focal adhesion signaling pathway provides theoretical basis for clinical transformation in IDD treatment.

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LDH nanoparticles with different elemental compositions are constructed to optimize the chondrogenic differentiation of hUC-MSCs.

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Optimized-LDH pretreated hUC-MSCs transplantation show recovery of disc space height and integrated tissue structure.

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ECM and focal adhesion signaling pathway play significant roles in LDH-promoted cell differentiation and tissue regeneration.

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Ion-specific optimizing LDH provides theoretical basis for clinical transformation on IDD treatment.

Comparison of endoscopic submucosal resection with ligation and endoscopic submucosal dissection for small rectal neuroendocrine tumors: A multicenter retrospective study

Objectives

Endoscopic submucosal resection with band ligation (ESMR‐L) and endoscopic submucosal dissection (ESD) are both standard endoscopic resection methods for rectal neuroendocrine tumors (NETs) <10 mm in size. However, there is no definitive consensus on which is better. Here, we compared the efficacy of ESMR‐L and ESD for small rectal NETs.

Methods

This was a multicenter retrospective cohort study including 205 patients with rectal NETs who underwent ESMR‐L or ESD. Treatment outcomes were compared by univariate analysis, multivariate analysis, and inverse probability treatment weighting (IPTW) using propensity scores. Subgroup analysis evaluated the impact of the endoscopist's experience on the technical outcome.

Results

Eighty‐nine patients were treated by ESMR‐L and 116 by ESD. The R0 resection rate was not significantly different between the two (90% vs. 92%, p = 0.73). The procedure time of ESMR‐L was significantly shorter than for ESD (17 min vs. 52 min, p < 0.01) and the hospitalization period was also significantly shorter (3 days vs. 5 days, p < 0.01). These results were confirmed by multivariate analysis and also after IPTW adjustment. The procedure time of ESD was significantly prolonged by a less‐experienced endoscopist (49 min vs. 70 min, p = 0.02), but that of ESMR‐L was not affected (17 min vs. 17 min, p = 0.27).

Conclusions

For small rectal NETs, both ESMR‐L and ESD showed similar high complete resection rates. However, considering the shorter procedure time and shorter hospitalization period, ESMR‐L is the more efficient treatment method, especially for less‐experienced endoscopists.

A case of multiple solitary neurofibromas located in the hypopharynx and cervical esophagus

A 50‐year‐old female was admitted to our hospital because of mild throat discomfort. Esophagogastroduodenoscopy demonstrated multiple 2–3 mm diameter whitish granules in her hypopharynx and cervical esophagus. Based on biopsy specimens, we considered the lesions to represent normal tissue or very mild mucosal dysplasia. However, S‐100 immunohistochemical staining 3 years later led to a diagnosis of multiple solitary neurofibromas located in the hypopharynx and cervical esophagus. Histological finding characteristics of neurofibroma were present in 72.7% of hypopharyngeal biopsy specimens and 33.3% of esophageal specimens. When diagnosing neurofibroma, it is important to perform biopsies at multiple locations and at different times and to enlist the cooperation of endoscopists and pathologists for immunohistochemical staining with S‐100.

Hemostasis using a covered self‐expandable metal stent for pseudoaneurysm bleeding from the perihilar bile duct

Although there are many reports of hemostasis with covered self‐expandable metal stent (CSEMS) for bleeding from the papilla of Vater and the intrapapillary and distal bile duct, there are rare reports of its use for hemostasis in the perihilar bile duct. We report the case of a patient undergoing supportive care for perihilar cholangiocarcinoma with acute cholecystitis after side‐by‐side placement of uncovered SEMS for perihilar bile duct obstruction. Percutaneous transhepatic gallbladder aspiration was performed upon admission, and hematemesis occurred the next day. Since computed tomography scanning showed a pseudoaneurysm in the right uncovered SEMS, hemostasis by interventional radiology (IVR) was performed thrice for massive bleeding; however, hemostasis could not be achieved. When endoscopic retrograde cholangiopancreatography was performed for scrutiny and treatment of melena and increased hepatobiliary enzyme, the endoscopic visual field could not be secured by bleeding, and changes in hemodynamics were observed; thus, IVR was required, but it was difficult to perform. Since bleeding from the right bile duct was expected, hemostasis was performed using CSEMS. This is the first report of hemostasis performed by placing a covered SEMS for bleeding from a pseudoaneurysm of the intrahepatic bile duct.

Can transcranial direct current stimulation (tDCS) of the cerebellum improve implicit social and cognitive sequence learning?

Accumulating evidence shows that the posterior cerebellum is involved in mentalizing inferences of social events by detecting sequence information in these events, and building and updating internal models of these sequences. By applying anodal and sham cerebellar transcranial direct current stimulation (tDCS) on the posteromedial cerebellum of healthy participants, and using a serial reaction time (SRT) task paradigm, the current study examined the causal involvement of the cerebellum in implicitly learning sequences of social beliefs of others (Belief SRT) and non-social colored shapes (Cognitive SRT). Apart from the social or cognitive domain differences, both tasks were structurally identical. Results of anodal stimulation (i.e., 2 mA for 20 min) during the social Belief SRT task, did not show significant improvement in reaction times, however it did reveal generally faster responses for the Cognitive SRT task. This improved performance could also be observed after the cessation of stimulation after 30 min, and up to one week later. Our findings suggest a general positive effect of anodal cerebellar tDCS on implicit non-social Cognitive sequence learning, supporting a causal role of the cerebellum in this learning process. We speculate that the lack of tDCS modulation of the social Belief SRT task is due to the familiar and overlearned nature of attributing social beliefs, suggesting that easy and automatized tasks leave little room for improvement through tDCS.

Successful treatment of mediastinal pancreatic pseudocyst and pancreatic pleural effusion with endoscopic pancreatic duct drainage: A case report

An 81‐year‐old man with chronic pancreatitis was being treated with a protease inhibitor. He developed an acute exacerbation of chronic pancreatitis and dyspnea. Contrast‐enhanced computed tomography showed disruption of the main pancreatic duct, a cystic lesion connecting the mediastinum to the main pancreatic duct, and left pleural effusion. We diagnosed a pancreatic pseudocyst, mediastinal pancreatic pseudocyst, and pancreatic pleural effusion. Endoscopic retrograde pancreatography showed leakage of contrast medium from the pancreatic body; furthermore, a cystic cavity extending to the mediastinum through a pancreatic duct fistula was visualized. An endoscopic transpapillary nasopancreatic drainage tube was placed in the cystic cavity. Computed tomography showed that the mediastinal pseudocyst and pleural effusion had disappeared. Endoscopic transpapillary pancreatic duct drainage may be useful when a connection between the main pancreatic duct and a mediastinal pseudocyst is confirmed by imaging.

Delayed perforation after cold snare polypectomy for small colonic polyps in a patient receiving oral corticosteroids

This case report describes a fatal outcome due to delayed perforation after cold snare polypectomy in a patient with bullous pemphigoid receiving oral corticosteroids. Cold snare polypectomy has become the standard treatment for small colorectal polyps because of the procedure's safety and simplicity. In this case, however, corticosteroid therapy and vasculitis may have caused local necrosis and tearing of the intestinal wall. Corticosteroids are widely used, and perforation after cold snare polypectomy is extremely rare. However, some patients on corticosteroid therapy may have special pathologies, such as in this case, and we advise physicians to use appropriate judgment and extreme caution in determining the indication for endoscopic therapy.

Treatment of efferent loop syndrome after pancreatoduodenectomy with a fully covered self‐expandable metal stent: A case report

Efferent loop syndrome is a very rare complication following pancreatoduodenectomy. The treatment of efferent loop syndrome varies depending on the cause of the syndrome. Conservative treatment methods, including nasogastric drainage and enteral nutrition, are adopted that are effective in most of patients; however, surgical treatment is usually required in patients with complete loop obstruction. Herein, we report a case of severe efferent loop obstruction that occurred after pancreatoduodenectomy, which was refractory to conservative treatment and successfully resolved by insertion of a fully covered self‐expandable metal stent.