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Abstract This study retrospectively evaluated the outcomes of endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) using novel electrocautery-enhanced lumen-apposing metal stents (LAMS) in high-risk patients with acute cholecystitis (AC). Between January 1, 2021, and November 30, 2022, 58 high-risk surgical patients with AC underwent EUS-GBD with the novel electrocautery-enhanced LAMS. The technical success rate was 94.8% (55/58), with one case of duodenal perforation requiring surgery with complete stent migration and two of partial stent migration into the gallbladder. However, the clinical success rate was 100% (55/55). Recurrent AC occurred in 3.6% of the cases (2/55), managed with double pigtail plastic stents through the LAMS. Early AEs observed in 1.8% (1/55) due to stent obstruction. Late AEs occurred in 5.4% (3/55), including two cases of cholangitis and one of stent obstruction. For 33 patients followed over 6 months, LAMS maintenance was sustained in 30 cases. Two patients underwent double-pigtail plastic stent replacement after LAMS removal, and one underwent LAMS removal during surgery following tumor stage regression after chemotherapy for cholangiocarcinoma. The novel electrocautery-enhanced LAMS demonstrated high technical and clinical success rates in high-risk surgical patients with AC, maintaining effective gallbladder drainage with minimal AEs during long-term follow-up, thus highlighting its efficacy and safety in challenging patients.

Background/Aims: There are no consensus guidelines for patients with acute cholecystitis undergoing percutaneous cholecystostomy who are unfit for interval cholecystectomy. The current study aimed to compare the clinical outcomes of endoscopic gallbladder drainage, i.e. conversion from percutaneous cholecystostomy (including endoscopic transpapillary gallbladder stenting and endoscopic ultrasound-guided gallbladder drainage), and conservative treatment after percutaneous cholecystostomy tube removal. Methods : This retrospective review included patients who underwent percutaneous cholecystostomy for acute cholecystitis between January 2017 and December 2020. Consecutive patients who underwent endoscopic gallbladder drainage or percutaneous cholecystostomy tube removal without interval cholecystectomy were included. Outcome measures included recurrent acute cholecystitis and unplanned readmission due to gallstone-related diseases. Results : During the study period, 238 patients were selected (63 underwent endoscopic gallbladder drainage conversion and 175 underwent conservative treatment). Patients who underwent endoscopic gallbladder drainage conversion had lower rates of recurrent acute cholecystitis (3 [4.76%] vs 31 [17.71%], p=0.012) and unplanned readmission due to gallstone-related diseases (6 [9.52%] vs 40 [22.86%], p=0.022) than those who underwent conservative treatment following percutaneous cholecystostomy tube removal. In the univariate and multivariate analyses, calculus cholecystitis (odds ratio, 13.75; 95% confidence interval, 1.83 to 102.83; p=0.011) and conversion of endoscopic gallbladder drainage (odds ratio, 0.23; 95% confidence interval, 0.06 to 0.78; p=0.019) were significant predictive factors for recurrent acute cholecystitis. Conclusion : s: Endoscopic gallbladder drainage conversion led to more favorable outcomes than conservative treatment after percutaneous cholecystostomy tube removal. Therefore, endoscopic gallbladder drainage conversion may be considered a promising treatment option for patients undergoing percutaneous cholecystostomy who are at a high surgical risk.

An ilio-iliac arteriovenous fistula (AVF) is rare. Common factors leading to ilio-iliac AVF include congenital malformations, iatrogeny, and trauma. There is limited documentation in the literature of cases involving ilio-iliac AVF with May-Thurner syndrome. Here, we present a case of an ilio-iliac AVF with May-Thurner syndrome in an 80-year-old male. CT and angiography confirmed extensive ilio-iliac AVF. Successful endovascular procedures for ilio-iliac AVF were performed using several variablesized coils and 1400–2000 μm gelatin particles. After embolization, follow-up abdominopelvic CT revealed an improvement in edema in the left leg.

Background/Aims: Most guidelines recommend surgical resection of all main duct (MD) and mixed-type (MT) intraductal papillary mucinous neoplasms (IPMNs) in suitable patients. However, there is little evidence regarding the malignancy risk of enhancing mural nodules (EMNs) that are present only in the main pancreatic duct (MPD) in patients with MD- and MT-IPMNs. Therefore, this study aimed to identify the clinical and morphological features associated with malignancy in MD- and MT-IPMNs with EMNs only in the MPD.Methods: We retrospectively enrolled 50 patients with MD- and MT-IPMNs with EMNs only in the MPD on contrast-enhanced magnetic resonance imaging. We evaluated the clinical characteristics and preoperative radiologic imaging results of MPD morphology and EMN size and analyzed the risk factors associated with malignancy.Results: Histological findings of EMNs were low-grade dysplasia (38%), malignant lesions (62%), high-grade dysplasia (34%), and invasive carcinoma (28%). On the receiver operating characteristic curve, the cutoff value of EMN size on magnetic resonance imaging for best predicting malignancy was 5 mm (sensitivity, 93.5%; specificity, 52.6%; area under the curve, 0.753). Multivariate analysis showed that only EMN >5 mm (odds ratio, 27.69; confidence interval, 2.75 to 278.73; p=0.050) was an independent risk factor for malignancy.Conclusions: EMNs of >5 mm are associated with malignancy in patients with MD- and MT-IPMNs with EMNs that are present only in the MPD, in accordance with the international consensus guidelines.

Background/Aims: This study aimed to evaluate the prevalence and natural progression of subepithelial lesions (SELs) in the upper gastrointestinal (UGI) tract. Methods: The medical records of patients with UGI SELs who underwent endoscopic screening at eight university hospitals between January and December 2010 were retrospectively investigated. The follow-up evaluations were performed until December 2016. Results: UGI SELs were found in 1,044 of the 65,233 participants screened (endoscopic prevalence, 1.60%; the total number of lesions, 1,062; mean age, 55.1±11.2 years; men, 53.6%). The median follow-up period was 48 (range, 8–74) months. SELs were most frequently found in the stomach (63.8%) and had a mean size of 9.9±6.1 mm. Endoscopic ultrasonography (EUS) was performed in 293 patients (28.1%). The most common lesions were leiomyomas, followed by gastrointestinal stromal tumors (GISTs), and ectopic pancreas. The proportions of SELs with malignant potential according to size were 3% (

Abstract Metabolism, is a complex process involving the gut and the liver tissue, is difficult to be reproduced in vitro with conventional single cell culture systems. To tackle this challenge, we developed a gut-liver-axis chip consisting of the gut epithelial cell chamber and three-dimensional (3D) uniform-sized liver spheroid chamber. Two cell culture chamber compartments were separated with a porous membrane to prevent microorganisms from passing through the chamber. When the hepG2 spheroids cultured with microbiota-derived metabolites, we observed the changes in the physiological function of hepG2 spheroids, showing that the albumin and urea secretion activity of liver spheroids was significantly enhanced. Additionally, the functional validation of hepG2 spheroids treated with microbiota-derived exosome was evaluated that the treatment of the microbiota-derived exosome significantly enhanced albumin and urea in hepG2 spheroids in a gut-liver axis chip. Therefore, this gut-liver axis chip could be a potentially powerful co-culture platform to study the interaction of microbiota and host cells. Graphical Abstract

Background/Aims: Endoscopic ultrasonography (EUS) provides high-resolution images and is superior to computed tomography (CT) scan in diagnosing small pancreatic ductal adenocarcinoma (PDAC). As a result, the use of EUS for early detection of PDAC has attracted attention. This study aimed to identify the clinical and radiological characteristics of patients with PDAC diagnosed by EUS but not found on CT scan. Methods: The medical records of patients diagnosed with PDAC at 12 tertiary referral centers in Korea from January 2003 to April 2019 were reviewed. This study included patients with pancreatic masses not clearly observed on CT scan but identified on EUS. The clinical characteristics and radiological features of the patients were analyzed, and survival analysis was performed. Results: A total of 83 patients were enrolled. The most common abnormal CT findings other than a definite mass was pancreatic duct dilatation, which was identified in 61 patients (73.5%). All but four patients underwent surgery. The final pathologic stages were as follows: IA (n=31, 39.2%), IB (n=8, 10.1%), IIA (n=20, 25.3%), IIB (n=17, 21.5%), III (n=2, 2.5%), and IV (n=1, 1.4%). The 5-year survival rate of these patients was 50.6% (95% confidence interval, 38.8% to 66.7%). Elevated liver function testing and R1 resection emerged as significant predictors of mortality in the multivariable Cox regression analysis. Conclusions: This multicenter study demonstrated favorable long-term prognosis in patients with PDAC diagnosed by EUS but indeterminate on CT scan. EUS should be considered for patients with suspected PDAC but indeterminate on CT scan.

EUS-guided drainage for gallbladder, bile duct, pancreatic duct, and peripancreatic fluid collection has been performed more frequently in the last decade. The development of dedicated stents and delivery systems for EUS-guided interventions have improved the efficacy and safety of these procedures. Furthermore, the introduction of lumen-apposing metal stents has reduced the complication significantly of endoscopic transmural drainage of pancreatic collections and gallbladder. Recent studies show that EUS-guided drainage of pancreaticobiliary ducts and peripancreatic fluid collection produces good results and low complication rates. This review describes the current position and role of interventional EUS for pancreatobiliary disease in clinical practice.

Background/Aims: Percutaneous transhepatic cholangioscopy (PTCS) is used for the diagnosis and treatment of biliary diseases in patients with failed endoscopic retrograde cholangiopancreatography, particularly those with surgically altered anatomy. However, few studies are available on the clinical use of Spyglass DS direct visualization system (SpyDS)-assisted PTCS. This study aimed to assess the efficacy and safety of SpyDS-assisted PTCS in patients with surgically altered anatomy, particularly those with a Roux-en-Y reconstruction. Methods: Thirteen patients (six women, median age 71.4 years [range, 53 to 83 years]) with surgically altered anatomy (four Roux-en-Y choledochojejunostomies, seven Roux-en-Y hepaticojejunostomies, and two Roux-en-Y esophagojejunostomies) who underwent SpyDS-assisted PTCS between January 2019 and August 2020 were included and the data was acquired by retrospectively reviewing electronic medical record. Results: A total of 19 SpyDS-assisted PTCS procedures were performed in the 13 patients: eight had bile-duct stones, and five had biliary strictures. All SpyDS-assisted PTCS procedures were successfully performed. The total procedure time was 42.42±18.0 minutes (mean±standard deviation). Bile duct clearance was achieved in all bile duct stone cases after a median of 2 (range, 1 to 3) procedures. In the five biliary stricture cases, the results of SpyBite forceps-guided targeted biopsy were consistent with adenocarcinoma (100% accuracy). The median hospitalization duration was 20 days (range, 14 to 30 days). No procedure-related morbidity or mortality occurred. Conclusions: SpyDS-assisted PTCS may be a safe, feasible, and effective procedure for the diagnosis and treatment of biliary diseases in patients with surgically altered anatomy, particularly in those with the Roux-en-Y reconstruction requiring a percutaneous approach. However, our findings need to be validated in further studies.

Background/Aims The utility of endoscopic ultrasonography (EUS) for differentiating gastrointestinal stromal tumors (GISTs) and leiomyomas of the stomach is not well known. We aimed to evaluate the ability of EUS for differentiating gastric GISTs and leiomyomas. Methods We retrospectively reviewed the medical records of patients with histopathologically proven GISTs (n=274) and leiomyomas (n=87). In two consensus meetings, the inter-observer variability in the EUS image analysis was reduced. Using logistic regression analyses, we selected predictive factors and constructed a predictive model and nomogram for differentiating GISTs from leiomyomas. A receiver operating characteristic (ROC) curve analysis was performed to measure the discrimination performance in the development and internal validation sets. Results Multivariate analysis identified heterogeneity (odds ratio [OR], 9.48), non-cardia (OR, 19.11), and older age (OR, 1.06) as independent predictors of GISTs. The areas under the ROC curve of the predictive model using age, sex, and four EUS factors (homogeneity, location, anechoic spaces, and dimpling or ulcer) were 0.916 (sensitivity, 0.908; specificity, 0.793) and 0.904 (sensitivity, 0.908; specificity, 0.782) in the development and internal validation sets, respectively. Conclusions The predictive model and nomogram using age, sex and homogeneity, tumor location, presence of anechoic spaces, and presence of dimpling or ulcer on EUS may facilitate differentiation between GISTs and leiomyomas.

Mirizzi syndrome is a rare complication of gallbladder disease that can be difficult to treat. In particular, endoscopic treatment often fails because of the inability to access or to capture the impacted cystic duct stone. We report a case of Mirizzi syndrome grade III that was successfully managed by digital single-operator peroral cholangioscopy-guided electrohydraulic lithotripsy with endoscopic nasogallbladder drainage and interval laparoscopic cholecystectomy. Based on our experience, digital single-operator peroral cholangioscopy-guided electrohydraulic lithotripsy with endoscopic nasogallbladder drainage is a feasible minimally invasive approach for the management of high-grade Mirizzi syndrome.

Spontaneous rupture of a hemorrhagic pancreatic pseudocyst may be life-threatening. Endoscopic ultrasound (EUS)-guided drainage has been reported to be a valuable treatment option for pancreatic pseudocysts. However, its usefulness in the management of a ruptured pancreatic pseudocyst is limited. We report a rare case of a spontaneous rupture of a hemorrhagic pancreatic pseudocyst in a patient with chronic pancreatitis, which was successfully treated with EUS-guided gastrocystostomy with a fully covered self-expandable metallic stent.

Obesity produces many health problems, including systemic oxidative stress. This study comprehensively investigated the effects of Sanguisorba officinalis L. extract (SO) as an antioxidant on abnormal lipid accumulation and oxidative stress in 3T3-L1 adipocytes and high-fat diet (HFD)-induced obese mice (n = 48). We evaluated the anti-adipogenic and antioxidant effects of SO on 3T3-L1 by cell viability, Oil red O staining, and NBT assays. The ameliorative effects of SO in HFD-induced C57BL/6J mice were investigated by measuring body weight, serum lipids, adipocyte size, hepatic steatosis, AMPK pathway-related proteins, and thermogenic factors. In addition, the effect of SO on oxidative stress in obese mice was evaluated by the activity of antioxidant enzymes and the production of lipid peroxidation products and ROS production in adipose tissue. We found that SO dose-dependently decreased lipid accumulation and ROS production in 3T3-L1 adipocytes. In C57BL/6J obese mice, SO (above 200 mg/kg) attenuated the HFD-induced gain in body weight and white adipose tissue (WAT) weight without affecting appetite. SO also decreased serum glucose, lipid, and leptin levels and attenuated adipocyte hypertrophy and hepatic steatosis. Furthermore, SO increased the expression of SOD1 and SOD2 in WAT, decreased ROS and lipid peroxides, and activated the AMPK pathway and thermogenic factors. In summary, SO reduces oxidative stress in adipose tissue by increasing antioxidant enzyme activity and improves obesity symptoms through AMPK-pathway-regulated energy metabolism and mitochondrial respiratory thermogenesis.

Solid pseudopapillary tumors of the pancreas are rare and typically occur in young women. Compared with pancreatic adenocarcinoma, solid pseudopapillary tumors are characterized by notable indolent biological behavior associated with a favorable prognosis. Despite their large size, these tumors rarely metastasize. Even in cases of hepatic metastasis, most lesions are usually solitary in distribution and are amenable to resection. We report a case of a 55-year-old man with a small solid pseudopapillary tumor (≤3-cm diameter) mimicking a pancreatic adenocarcinoma, with multiple hepatic metastases. The diagnosis was confirmed by endoscopic ultrasound-guided fine-needle biopsy using a 22-G core needle. Unfortunately, rapid tumor progression led to patient mortality 5 months after diagnosis. To our knowledge, this is the first case report that describes a small solid pseudopapillary tumor of the pancreas with multiple hepatic metastasis and poor prognosis in a patient who was diagnosed with this condition at the time of initial diagnosis.

Background/Aims: Advanced biliary tract cancer (BTC) is associated with poor survival. A recent phase II study of triplet combination chemotherapy, including gemcitabine, cisplatin, and nanoparticle albumin-bound (nab)-paclitaxel, has shown promising results. This study aimed to compare the efficacy of triplet and standard doublet chemotherapy in a real-world setting. Methods: Patients with advanced BTC treated with triplet and doublet chemotherapy regimens were recruited. The propensity-score nearest neighbor matching method with a ratio of one-to-one was used to create a matched cohort for comparison. Progression-free survival (PFS), overall survival (OS), and safety profiles were examined in both groups. Results: A total of 68 patients (n=34 per group) were included in the matched cohort, and their baseline characteristics were well balanced. Survival outcomes in the triplet chemotherapy group were not better than those in the doublet chemotherapy group, with a median PFS of 7.5 months (95% confidence interval [CI], 4.1 to 10.9) versus 7.2 months (95% CI, 5.6 to 8.9) (hazard ratio [HR], 0.93; 95% CI, 0.53 to 1.62; p=0.793) and a median OS of 13.7 months (95% CI, 8.8 to 18.7) versus 12.2 months (95% CI, 8.4 to 16.0) (HR 0.73; 95% CI, 0.38 to 1.41; p=0.354), respectively. In addition, the treatment-related severe adverse events, such as neutropenia, were more common in the triplet chemotherapy group. Conclusions: Gemcitabine, cisplatin, and nab-paclitaxel did not improve the PFS or OS compared to that achieved by standard chemotherapy in patients with advanced BTC. The benefits of triplet chemotherapy in advanced BTC require examination in large randomized controlled trials.

A three-dimensional (3D) tumor spheroid model plays a critical role in mimicking tumor microenvironments in vivo. However, the conventional culture methods lack the ability to manipulate the 3D tumor spheroids in a homogeneous manner. To address this limitation, we developed a microfluidic-based droplet system for drug screening applications. We used a tree-shaped gradient generator to control the cell density and encapsulate the cells within uniform-sized droplets to generate a 3D gradient-sized tumor spheroid. Using this microfluidic-based droplet system, we demonstrated the high-throughput generation of uniform 3D tumor spheroids containing various cellular ratios for the analysis of the anti-cancer drug cytotoxicity. Consequently, this microfluidic-based gradient droplet generator could be a potentially powerful tool for anti-cancer drug screening applications.

Background/Aims This study aimed to evaluate the feasibility and efficacy of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a core needle for hepatic solid masses (HSMs). Additionally, the study aimed to assess factors that influence the diagnostic accuracy of EUS-FNB for HSMs. Methods A retrospective analysis of patients who underwent EUS-FNB for the pathological diagnosis of HSMs was conducted between January 2013 and July 2017. The procedure had been performed using core needles of different calibers. The assessed variables were mass size, puncture route, needle type, and the number of needle passes. Results Fifty-eight patients underwent EUS-FNB for the pathologic evaluation of HSMs with a mean mass size of 21.4±9.2 mm. EUS-FNB was performed with either a 20-G (n=14), 22-G (n=29) or a 25-G core needle (n=15). The diagnostic accuracy for this procedure was 89.7%, but both specimen adequacy for histology and available immunohistochemistry stain were 91.4%. The sensitivity and specificity of EUS-FNB were 89.7% and 100%, respectively. There was one case involving bleeding as a complication, which was controlled with endoscopic hemostasis. According to the multivariate analysis, no variable was independently associated with a correct final diagnosis. Conclusions EUS-FNB with core biopsy needle is a safe and highly accurate diagnostic option for assessing HSMs. There were no variable factors associated with diagnostic accuracy.

Abstract We have explored the effect of post-annealing on the electrical properties of an indium gallium zinc oxide (IGZO) transistor with an Al2O3 bottom gate dielectric, formed by a sol–gel process. The post-annealed IGZO device demonstrated improved electrical performance in terms of threshold variation, on/off ratio, subthreshold swing, and mobility compared to the non-annealed reference device. Capacitance–voltage measurement confirmed that annealing can lead to enhanced capacitance properties due to reduced charge trapping. Depth profile analysis using X-ray photoelectron spectroscopy proved that percentage of both the oxygen vacancy (VO) and the hydroxyl groups (M–OH) within the IGZO/Al2O3 layers, which serve as a charge trapping source, can be substantially reduced by annealing the fabricated transistor device. Furthermore, the undesired degradation of the contact interface between source/drain electrode and the channel, which mainly concerns VO, can be largely prevented by post-annealing. Thus, the facile annealing process also improves the electrical bias stress stability. This simple post annealing approach provides a strategy for realising better performance and reliability of the solid sol–gel oxide transistor.

ObjectivesEndoscopic transpapillary gallbladder drainage (ETGBD) has been proposed as an alternative to surgery or percutaneous cholecystostomy in patients with acute calculus cholecystitis (ACC). We aimed to evaluate the safety and efficacy of ETGBD via endoscopic transpapillary gallbladder stenting (ETGBS) or endoscopic naso-gallbladder drainage (ENGBD) as either a bridging or a definitive treatment option for patients with ACC when a cholecystectomy is delayed or cannot be performed.MethodsFrom July 2014 to December 2018, 171 patients with ACC in whom ETGBD were attempted were retrospectively reviewed. The technical and clinical success rates and adverse events were evaluated. Moreover, the predictive factors for technical success and the stent patency in the ETGBS group with high surgical risk were examined.ResultsThe technical and clinical success rates by intention-to-treat analysis for ETGBD were 90.6% (155/171) and 90.1% (154/171), respectively. Visible cystic duct on cholangiography were significant technical success predictor (adjusted odds ratio: 7.099, 95% confidence interval: 1.983-25.407, P = 0.003) as per logistic regression analysis. Adverse events occurred in 12.2% of patients (21/171: mild pancreatitis, n = 9; acute cholangitis, n = 6; post-endoscopic sphincterotomy bleeding, n = 4; and stent migration, n = 1; ACC recurrence, n = 1), but all patients were treated with conservative management and endoscopic treatment. Among the ETGBS group, the median stent patency in 70 patients with high surgical risk was 503 days (interquartile range: 404.25-775 days).ConclusionsETGBD, using either ETGBS or ENGBD, may be a suitable bridging option for ACC patients unfit for urgent cholecystectomy. In high surgical risk patients, ETGBS may be a promising and useful treatment modality with low ACC recurrence.

Abstract Background Endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) may facilitate tissue acquisition for a definitive diagnosis of gastrointestinal subepithelial tumors (SETs). This study aimed to determine the diagnostic yield of EUS-FNB using a novel 20-gauge ProCore needle with a coiled sheath in tissue sampling of gastrointestinal SETs. Methods Between July 2016 and February 2017, 39 patients with gastrointestinal SETs were prospectively recruited from six university hospitals in Korea. Hypoechoic SETs ≥2 cm in size and originating from the submucosal and/or muscularis propria layer under EUS were eligible. This study was registered on ClinicalTrials.gov (NCT02884154). Results A total of 36 patients were included in the final analyses. EUS-FNB was diagnostic in 88.9% of SETs. Tissue adequacy was judged as optimal in 97.2% of FNB specimens according to on-site visual evaluation by endosonographers, and in 88.9% of specimens according to pathologists. A macroscopically optimal core sample was obtained with two needle passes in 94.4% of cases. Technical failure rate was encountered in two cases (5.6%) after two needle passes. There were two cases (5.6%) of bleeding, which was managed endoscopically. Conclusions EUS-FNB using a 20-gauge ProCore needle is a technically feasible and effective modality for histopathologic diagnosis of gastrointestinal SETs, providing adequate core samples with fewer needle passes;ClinicalTrials.gov number, NCT02884154.

The semiconductor manufacturing processes have been evolved to improve the yield rate. Here, we studied a sequential and comprehensive algorithm that could be used for fault detection and classification (FDC) of the semiconductor chips. A statistical process control (SPC) method is employed for inspecting whether sensors used in the semiconductor manufacturing process become stable or not. When the sensors are individually stable, the algorithm conducts the relational inspection to identify the relationship between two sensors. The key factor here is the coefficient of determination (R2). If R2 is calculated as more than 0.7, their relationship is analyzed through the regression analysis, while the algorithm conducts the clustering analysis to the sensor pair with R2 less than 0.7. This analysis also provided the capability to determine whether the newly generated data are defective or defect-free. Therefore, this study is not only applied to the semiconductor manufacturing process but can also be to the various research fields where the big data are treated.

An isolated pyogenic pancreatic abscess (IPPA) without pancreatitis is extremely rare but can occur in patients with uncontrolled diabetes. This pathologic condition poses a clinical challenge in diagnosis and management because it can be confused easily with a malignancy. Endoscopic ultrasound (EUS) may be a useful diagnostic modality for indeterminate pancreatic lesions and IPPA. Here, we report two cases with elevated carbohydrate antigen 19-9 levels and pancreatic masses on cross sectional imaging. The patients were subsequently diagnosed with IPPA by EUS. EUS-guided drainage was performed successfully and the patients’ clinical symptoms and radiologic findings improved. In our experience, EUS and EUS-guided drainage are crucial steps for the diagnosis and management of patients with an indeterminate pancreatic lesion. In addition, EUS-guided drainage has excellent technical and clinical outcomes for the treatment of IPPA.

Most esophageal lipomas are discovered incidentally and are small and asymptomatic. However, large (＞4 cm) lipomas may cause various symptoms, including dysphagia, regurgitation, or epigastric discomfort. We present a 45-year-old woman with intermittent sudden choking and globus pharyngeus. Upper gastrointestinal endoscopy and endoscopic ultrasound revealed an approximately 10.0×1.5 cm pedunculated subepithelial tumor in the upper esophagus, identified as the cause of her symptoms. A thoracic computed tomography scan revealed a fat attenuated longitudinal mass along the upper esophagus, suggestive of a lipoma. Endoscopic resection of the lesion was performed with a detachable snare to relieve her symptoms, and the pathologic findings were consistent with a lipoma. (Korean J Gastroenterol 2016;68:210-213)

A 75-year-old woman with hypertension presented with acute suppurative cholangitis. Chest radiography revealed severe kyphosis. Abdominal computed tomography revealed a large stone impacted in the common bile duct (CBD). The patient underwent emergent endoscopic retrograde cholangiopancreatography, and cholangiography revealed a large stone (7×3 cm) in the CBD that could not be captured using a large basket. We could not use the percutaneous approach for stone fragmentation by using a cholangioscope because of severe degenerative kyphosis. Finally, we performed holmium laser lithotripsy under peroral cholangioscopy by using an ultraslim endoscope, and the large stone in the CBD was successfully fragmented and removed without complications.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is commonly used to obtain tissue external to the gastrointestinal tract. EUS-FNA is relatively safe, but occasionally adverse events have been reported. There is scarcity of data on risk factors of adverse events. The aim of this study is to identify risk factors associated with EUS-FNA.In this multicenter case-control study, we retrospectively reviewed 4,097 cases between 2009 and 2012 at 15 hospitals in Korea. Among the patients there were 104 cases (2.5%) who had adverse events of which 12 (0.29%) were severe. We matched 520 controls (1:5 ratios) stratified by hospital to analyze the potential risk factors.The most common adverse events were pancreatitis (45/104, 43.3%) and infection (46/104, 44.2%). Endoscopic retrograde cholangiopancreatography (ERCP) on the same day was a risk factor of all adverse events [OR = 2.41, 95% CI (1.41, 4.12)], pancreatitis [OR = 2.31, 95% CI (1.02, 5.25)], and infection [OR = 2.75, 95% CI (1.31, 5.78)]. More than 15 to-and-fro movements during puncture increased the risk of pancreatitis [OR = 2.30, 95% CI (1.11, 4.77)] and infection [OR = 3.65, 95% CI (1.55, 8.59)]. A higher number of punctures was positively correlated with pancreatitis [OR = 1.34, 95% CI (1.08, 1.67)] but negatively correlated with infection [OR = 0.66, 95% CI (0.48, 0.89)].EUS-FNA is a safe procedure in which serious adverse events are rare. We define some risk factors of adverse events during EUS-FNA, including ERCP on the same day, a higher number of punctures, and more than 15 to-and-fro movements.

The fermi-level pinning phenomenon, which occurs at the metal−semiconductor interface, not only obstructs the achievement of high-performance field effect transistors (FETs) but also results in poor long-term stability. This paper reports on the improvement in gate-bias stress stability in two-dimensional (2D) transition metal dichalcogenide (TMD) FETs with a titanium dioxide (TiO2) interfacial layer inserted between the 2D TMDs (MoS2 or WS2) and metal electrodes. Compared to the control MoS2, the device without the TiO2 layer, the TiO2 interfacial layer deposited on 2D TMDs could lead to more effective carrier modulation by simply changing the contact metal, thereby improving the performance of the Schottky-barrier-modulated FET device. The TiO2 layer could also suppress the Fermi-level pinning phenomenon usually fixed to the metal−semiconductor interface, resulting in an improvement in transistor performance. Especially, the introduction of the TiO2 layer contributed to achieving stable device performance. Threshold voltage variation of MoS2 and WS2 FETs with the TiO2 interfacial layer was ~2 V and ~3.6 V, respectively. The theoretical result of the density function theory validated that mid-gap energy states created within the bandgap of 2D MoS2 can cause a doping effect. The simple approach of introducing a thin interfacial oxide layer offers a promising way toward the implementation of high-performance 2D TMD-based logic circuits.

Autoimmune hepatitis (AIH) has been reported in association with Sjögren's syndrome (SS). Drug-induced AIH has been rarely reported. A rare case of the co-development of AIH and SS in a 53-year-old woman after the consumption of herbal medicines is described. After admission, the patient complained of dryness in her mouth, and she was subsequently diagnosed with SS, which had not been detected previously. The patient's bilirubin and aminotransferase levels initially decreased following conservative management; however, they later began to progressively increase. A diagnosis of AIH was made based on the scoring system proposed by the International Autoimmune Hepatitis Group. The patient was administered a combination of prednisolone and azathioprine, and the results of follow-up liver-function tests were found to be within the normal range. This is an unusual case of AIH and SS triggered simultaneously by the administration of herbal medicines.

This paper introduces a thin, polarizationinsensitive (PI), and multiple-band electromagnetic metamaterial absorber (MMA). The unit cell of the MMA consists of a slotted octagonal metallic patch printed on an FR4 dielectric substrate, backed by a grounded metallic layer, and notably does not incorporate resistive lumped elements. The proposed MMA exhibits measured absorption, exceeding 75% for normal incidence, across frequency bands ranging from 2.22– 2.38 GHz, 6.86–7.24 GHz, 11.68–12.71 GHz, 14.1–14.8 GHz, and 15.47–16 GHz. The proposed MMA unit cell has dimensions of 0.21λ0 × 0.21λ0 and a thickness of 0.001λ0, where λ0 represents the wavelength corresponding to the lowest frequency at 2.22 GHz. The performance of the proposed MMA is simulated using CST Microwave Studio and MATLAB, and subsequently validated through experimental measurements. [ABSTRACT FROM AUTHOR]