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In electronic warfare systems, detecting low-probability-of-intercept (LPI) radar signals poses a significant challenge due to the signal power being lower than the noise power. Techniques using statistical or deep learning models have been proposed for detecting low-power signals. However, as these methods overlook the inherent characteristics of radar signals, they possess limitations in radar signal detection performance. We introduce a deep learning-based detection model that capitalizes on the periodicity characteristic of radar signals. The periodic autocorrelation function (PACF) is an effective time-series data analysis method to capture the pulse repetition characteristic in the intercepted signal. Our detection model extracts radar signal features from PACF and then detects the signal using a neural network employing long short-term memory to effectively process time-series features. The simulation results show that our detection model outperforms existing deep learning-based models that use conventional autocorrelation function or spectrogram as an input. Furthermore, the robust feature extraction technique allows our proposed model to achieve high performance even with a shallow neural network architecture and provides a lighter model than existing models. [ABSTRACT FROM AUTHOR]

A clinical efficacy study of 0.025-inch guidewires (GWs) according to mechanical property analysis has not been reported yet. This study was designed to evaluate the clinical efficacy of a newly developed 0.025-inch GW for biliary access according to the basic mechanical property. Commercially available 0.025-inch GWs were in vitro tested based on parameters of mechanical property. Patients with naïve papilla requiring diagnostic or therapeutic ERCP were randomly assigned to an experimental 0.025-inch newly developed GW or a control 0.025-inch GW group. Technical success rate of wire-guided cannulation (WGC), difficult biliary cannulation (DBC), and adverse event rates were measured in this multicenter randomized trial. The technical success rate of primary WGC was 79.1% (151 of 191) in the experimental group and 70.8% (131 of 185) in the control group (95% two-sided confidence interval: 8.25%; p < 0.001; for a noninferiority margin of 15%). The technical success rate including cross-over to each other was also non-inferior. However, the chi-square test showed a statistical difference (81.7% vs. 68.1%; p = 0.002). Median biliary cannulation time was shorter in the experimental group (53 s vs. 77 s; p = 0.047). The rate of DBC was more frequent in the control group (34.6% vs. 50.3% p = 0.002). Multivariate analysis revealed that control group was one of contributing factors for DBC. Overall rate of post-ERCP pancreatitis was not different (4.7% vs. 8.6%; p = 0.125). WGC using a newly developed GW with superior physical performance GW in a bench test showed similar clinical efficacy and the rate of DBC was significantly lower in experimental GW. [ABSTRACT FROM AUTHOR]

The choice of a group decision-making rule is one of the most important political issues. Buchanan and Tullock have provided a framework for analyzing the optimal k-majority rule from the perspective of "methodological individualism." They proposed the concept of "external costs" and "decision costs" and argued that the optimal k-majority rule takes place where the sum of these two costs–"total costs"–is minimized. Despite the fact that the approach is widely accepted as a tool for dealing with public decision-making rules, the study of formalizing these two costs in a quantitative manner has been relatively rare. We propose a systematic way of modeling these costs considering the assumptions mentioned by Buchanan and Tullock. We find that the resulting shape of the graphs is generally similar to that of the Buchanan-Tullock model, except for some minor details. Then, using this analytical model, we investigate several factors that could affect Buchanan-Tullock's two costs and the optimal k-majority rule. We show that "clustering of disadvantages" (social factor) and "loss aversion" (personal factor) could increase external costs in Buchanan-Tullock's model. These factors can result in a separation between the theoretical and actual optimal k-majority rules. Meanwhile, some recent developments in information and communication technologies can not only decrease decision costs, but also increase the same costs simultaneously through amplified "group polarization" (technological factor). If the effect of the former is not the same as that of the latter, this leads to a difference in optimal k-majority rules as well. These discrepancies bring us to the dilemma of "public choice before public choice." [ABSTRACT FROM AUTHOR]

Background and Aim: Endoscopic ultrasound‐guided pancreatic duct drainage (EUS‐PD) has been proposed for pancreatic duct obstruction after failure of endoscopic retrograde pancreatography. We evaluate the long‐term outcomes of EUS‐PD using a fully covered self‐expandable metal stent (FCSEMS) for pancreaticojejunal anastomosis (PJA) strictures following Whipple procedures. Methods: Twenty‐three patients with PJA strictures underwent EUS‐PD according to the findings of EUS‐guided pancreatogram and the passage of the guidewire through PJA stricture (complete vs partial stricture) after failure of endoscopic retrograde pancreatography. Technical and clinical success, adverse events (AEs), and long‐term outcomes were assessed. Results: Technical and clinical success was achieved in all patients. The complete and partial strictures were 11 and 12, respectively. The direct transanastomotic and transmural plastic stenting in partial PJA stricture was successful in only three patients (13%). Therefore, 20 patients underwent EUS‐guided transmural FCSEMS placement during the initial attempt. Early AEs, including abdominal pain (n = 3) and peripancreatic fluid collection (n = 1), occurred in four patients (17.4%). During the follow‐up periods (median, 27.2 months; interquartile range [IQR], 18.7–40.6), five patients (21.7%) developed late AEs, including asymptomatic stent fracture at the gastric end (n = 3), asymptomatic stent migration (n = 1), and stent occlusion (n = 1). The total duration of stent placement was 27.2 months (IQR, 18.7–40.6), and the median number of stent revision was 2 (IQR, 1–2). Conclusions: In terms of safety and efficacy, EUS‐PD with an FCSEMS showed favorable success and acceptable AEs rate and durable long‐term outcomes. [ABSTRACT FROM AUTHOR]

Backgrounds: A two-stage procedure involving endoscopic retrograde cholangiopancreatography (ERCP), followed by cholecystectomy, is one of the primary treatments of concomitant gallstones and choledocholithiasis. However, negative findings on ERCP and migrating gallstones after cholecystectomy are major concerns. This study aimed to identify the prevalence of unnecessary ERCP and to develop and validate a predictive nomogram using preoperative factors in patients who underwent a two-stage procedure.Methods: Consecutive 931 patients were treated with the two-stage procedure for evident gallstones and suspected choledocholithiasis. After the cholecystectomy, a cholangiogram was performed to confirm the absence of the migrating gallstones. The patients were divided into derivation (n = 652) and validation (n = 279) cohorts.Results: A total of 26.5% (247/931) patients had unnecessary ERCP (negative choledocholithiasis, 14.6%; migrating gallstones, 11.9%). No stones on images (P < 0.001), total bilirubin < 1.2 mg/dL (P = 0.006), and common bile duct diameter < 8.0 mm (P = 0.004) were independent factors associated with negative finding on ERCP with a validated nomogram area under the curve (AUC) of 0.72 (95% confidence interval [CI] 0.64-0.80). For migrating gallstones after cholecystectomy, radiolucent gallstones (P < 0.001), gallstone size ≤ 6.4 mm (P = 0.001), cystic duct stones (P < 0.001), gallbladder wall thickness ≥ 3.2 mm (P = 0.003), and low-lying cystic duct (P < 0.001) were independent factors with a validated nomogram AUC of 0.77 (95% CI 0.68-0.87).Conclusions: About one fourth of the patients may have unnecessary ERCP in the two-stage procedure. Based on our nomogram using preoperative factors, high-risk patients who are more likely to perform unnecessary ERCP could be considered for the one-stage procedure. [ABSTRACT FROM AUTHOR]

Background and Aim: Little is known about the standard care of small (<2 cm in diameter) pancreatic neuroendocrine tumors (PNET). The aim of the present study was to determine the clinical outcomes of small PNET after endoscopic ultrasound (EUS)‐guided ethanol‐lipiodol ablation (EUS‐ELA). Methods: In this prospective cohort study, consecutive patients who underwent EUS‐ELA for PNET were enrolled and were followed for ≥3 years. Treatment efficacy was the primary outcome measure. Results: In total, 33 patients who had 40 pathologically confirmed PNET (<2 cm in diameter) were enrolled for final analysis. A total of 63 EUS‐ELA sessions were successfully carried out (mean, 1.9 sessions per patient, 1.6 sessions per tumor), which included 40 initial sessions and 23 repeated sessions owing to incomplete ablation. Median actual volume of ethanol‐lipiodol mixture injected per session was 1.1 mL (IQR 0.8–1.9 mL). Complete ablation was achieved in 24 of 40 tumors (60%) with one (18 tumors, 45%) or two (24 tumors, 60%) sessions of EUS‐ELA. Lipiodol retention within tumor had better treatment outcomes (P = 0.004). Rate of procedure‐related adverse events was 3.2%. No malignancy or lymph node metastasis was discovered during a median follow up of 42 months (IQR 39–46 months). Conclusions: We found that EUS‐ELA was a safe and effective alternative option in the management of PNET <2.0 cm in diameter; 60% of patients achieved complete ablation. Lipiodol retention within tumor may be a useful early predictor of treatment effectiveness. Trial registered at ClinicalTrials.gov (NCT 01902238). [ABSTRACT FROM AUTHOR]

Background and Aims EUS-guided biliary drainage (EUS-BD) has been proposed as an alternative for patients after failed ERCP. To date, the evaluation of dedicated device for one-step EUS-BD has been limited. To determine feasibility and safety of a newly designed 7F stent introducer with tapered metal tip as a push-type dilator for one-step metal stent placement without additional fistula dilation in EUS-BD. Methods Thirty-two patients with malignant biliary obstruction and failed ERCP were randomly assigned to a dedicated stent introducer with a modified hybrid metal stent (DH group, n = 16) or a conventional 8.5F biliary metal stent introducer with a fully covered metal stent (FC group, n = 16). The technical success, procedural times, clinical success rate, and adverse event rates were evaluated. Results One-step technical success without additional fistula dilation in the DH was 88% (14/16). Multi-step process in a stent placement was performed in all patients of the FC group. The procedural time in the DH was significantly shorter than the FC (10 vs. 15 min, P = 0.007). No difference in overall technical or clinical success was seen between the groups. The rate of an early adverse event was common in the FC compared with the DH (31.3% [5/16] in the FC vs. 6.3% [1/16] in the DH, P = 0.172), although not statistically significant. Conclusions A dedicated device for one-step EUS-BD may be technically feasible, safe, and shorten the procedural times with less chance of an additional fistula dilation process, resulting in a potential reduction of the early adverse events. [ABSTRACT FROM AUTHOR]

Abstract: Background: Hilar cholangiocarcinoma is an uncommon cancer and its overall incidence is increasing. Photodynamic therapy (PDT) has been proposed as palliative management for unresectable hilar cholangiocarcinoma (UHC). To date, little is known about the role of the addition of systemic chemotherapy to PDT for UHC. We performed a prospective, randomised, phase II trial to compare PDT plus S-1 and PDT alone for UHC. Methods: Patients with UHC were randomly assigned (in a 1:1 ratio) to PDT plus S-1 or PDT alone. The primary end-point was overall survival. The secondary end-points were progression-free survival, complications, re-intervention rate and quality of life. This trial is registered with clinicalTrials.gov, number NCT00869635. Findings: Between February 2009 and May 2012, we randomly assigned 21 patients to receive PDT plus S-1 and 22 to receive PDT alone. The UHC patients treated with PDT plus S-1 showed higher 1-year survival rate compared with the patients treated with PDT alone (76.2% versus 32%, P =0.003) and prolonged overall survival (median 17months, 95% confidence interval [CI]: 12.6–21.4, versus 8months, 95% CI: 6–10, P =0.005, hazard ratio [HR], 0.36; 95% CI: 0.17–0.75). Regarding the secondary end-points, PDT plus S-1 was associated with prolonged progression-free survival compared with PDT alone (median 10months [95% CI: 4.1–16] versus 2months [95% CI: 0.4–3.5], P =0.009 (HR for progression 0.39, 95% CI: 0.19–0.83). There were no differences in the number of PDT sessions, the frequency of cholangitis, overall adverse events or the quality of life in either group. Interpretations: PDT plus S-1 was well tolerated and was associated with a significant improvement of overall survival and progression-free survival compared with PDT alone in patients with UHC. These findings warrant further clinical investigation of PDT plus S-1 in patients with UHC. [Copyright &y& Elsevier]

OBJECTIVES:Endoscopic ultrasound (EUS)-guided biliary drainage (EUSBD) with plastic stents has been introduced as an alternative to percutaneous transhepatic biliary drainage (PTBD) in cases of biliary obstruction when endoscopic retrograde cholangiopancreatography (ERCP) is unsuccessful. Although self-expandable metallic stents with a larger diameter might offer long-lasting patency compared with plastic stents, to date, EUSBD with one-step placement of a fully covered self-expandable metal stent (FCSEMS) has not been evaluated. We conducted this study to determine the feasibility and usefulness of EUSBD with one-step placement of FCSEMS.METHODS:A prospective feasibility study on EUSBD with one-step placement of FCSEMS was carried out in 14 patients with malignant biliary obstruction who were candidates for alternative techniques for biliary decompression because of unsuccessful ERCP.RESULTS:The technical and functional success rate was 100% (14/14). Nine patients were treated using the intrahepatic approach. The remaining five patients were treated using the extrahepatic approach. With the intrahepatic approach, two patients showed self-limited pneumoperitoneum. With the extrahepatic approach, no patients had pneumoperitoneum. No bile peritonitis or cholangitis was observed after the procedure in any of the patients treated using the intra- or extrahepatic approach. During follow-up periods (median 6 months), one case of re-intervention (7%, 1/14) necessitated by distal stent migration was observed.CONCLUSIONS:EUSBD with one-step placement of an FCSEMS may be feasible, safe, and effective as an alternative to PTBD in cases of malignant biliary obstruction when ERCP is unsuccessful. Prospective randomized trials of EUSBD with plastic stent vs. EUSBD with FCSEMS may be needed. [ABSTRACT FROM AUTHOR]

In this paper energy flow models for the transverse vibration of finite orthotropic plates are developed. These models are expressed with time- and locally space-averaged far-field energy density, and show more general forms than the conventional EFA models for isotropic plates. To verify the accuracy of the developed models, numerical analyses are performed for finite rectangular plates vibrating at a single frequency, and the calculated results expressed with the energy and intensity levels are compared with those of classical models by changing the frequency and the damping. [ABSTRACT FROM AUTHOR]

Background and Aim: Endoscopic ultrasound (EUS)‐guided biliary drainage is being increasingly performed as an alternative to percutaneous transhepatic biliary drainage (PTBD) to treat malignant hilar obstruction (MHO) after failed endoscopic retrograde cholangiopancreatography (ERCP). However, no study has compared EUS‐guided hepaticoduodenostomy (EUS‐HDS) with PTBD for right intrahepatic duct (IHD) obstruction after failed ERCP in patients with unresectable MHO. Methods: We retrospectively reviewed the data of consecutive patients with right IHD obstruction developed by unresectable MHO who underwent EUS‐HDS or PTBD after a previous placement of a stent in the left and/or right IHD between March 2018 and October 2021. Technical success, clinical success, stent or tube‐related adverse events, frequency of reintervention, and stent patency were evaluated. Results: A total of 42 patients (18 EUS‐HDS, 24 PTBD) were analyzed. Both groups did not show significant differences in technical success (EUS‐HDS, 94% vs PTBD, 100%; P = 0.429), clinical success (83% vs 83%; P = 0.999), early adverse events (24% vs 46%; P = 0.144), and stent or tube‐related late adverse events (29% vs 54%; P = 0.116). During follow‐up, the EUS‐HDS group had a longer median duration of patency (131 days vs 58.5 days; P = 0.041), and lower mean frequency of reinterventions per patient (0.35 vs 1.92; P = 0.030) than the PTBD group. Conclusions: EUS‐HDS showed comparable efficacy and safety to PTBD for drainage of the right biliary system and produced longer duration of patency and lower frequency of reinterventions in patients with unresectable MHO. [ABSTRACT FROM AUTHOR]

See article in J. Gastroenterol. Hepatol. 2011; 26: 1552-1558. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Identification of a Novel Antibody Associated With Autoimmune Pancreatitis," by L. Frulloni and colleagues in the November 26, 2009 issue.

Objectives: Many studies showed better outcomes of endoscopic ultrasound‐guided gallbladder drainage (EUS‐GBD) when compared with percutaneous transhepatic gallbladder drainage (P‐GBD) in which most tubes were left in situ. However, no studies have directly compared EUS‐GBD with P‐GBD after tube removal (ex situ). We compared the long‐term outcomes of EUS‐GBD and ex situ or in situ P‐GBD in high surgical risk patients with acute cholecystitis. Methods: We reviewed the records of 182 patients (EUS‐GBD, n = 75; P‐GBD, n = 107) who underwent gallbladder drainage. The procedural outcomes, long‐term outcomes, and adverse events were compared. Results: The EUS‐GBD group and the P‐GBD group had similar rates of technical and clinical success. Early adverse events were less common in the EUS‐GBD group (5.5% vs. 18.9%, P = 0.010). The long‐term outcomes were evaluated in 168 patients (EUS‐GBD, n = 67; P‐GBD ex situ, n = 84; P‐GBD in situ, n = 17). The rate of cholecystitis recurrence in the EUS‐GBD group (6.0%) was similar to that in the P‐GBD ex situ group (9.6%, P = 0.422), but significantly lower than that in the P‐GBD in situ group (23.5%, P = 0.049). P‐GBD in situ was a significant predictor of recurrent cholecystitis (hazard ratio 14.6; 95% confidence interval 2.9–72.8). Conclusion: The long‐term recurrence rate of acute cholecystitis in patients who underwent EUS‐GBD was comparable to that in patients whose P‐GBD could be removed. However, patients in whom P‐GBD could not be removed showed higher rates of recurrent cholecystitis than patients with EUS‐GBD. [ABSTRACT FROM AUTHOR]

Objectives: The goal of the study was to determine whether endoscopic ultrasound (EUS)-guided biliary drainage (EUS-BD) is comparable to conventional transpapillary stenting with endoscopic retrograde cholangiopancreatography (ERCP) in palliation of malignant distal biliary obstruction. Although ERCP for the palliation of malignant biliary obstruction is the standard of care, post-procedure pancreatitis and stent dysfunctions are not uncommon. While EUS-BD has garnered interest as a viable alternative when ERCP is impossible, its role as a primary palliation of malignant distal biliary obstruction is yet to be proven.Methods: We performed random allocation to EUS-BD or ERCP in 125 patients with unresectable malignant distal biliary obstruction at four tertiary academic referral centers in South Korea.Results: Technical success rates were 93.8% (60/64) for EUS-BD and 90.2% (55/61) for ERCP (difference 3.6%, 95% 1-sided confidence interval lower limit −4.4%, P = 0.003 for noninferiority margin of 10%). Clinical success rates were 90.0% (54/60) in EUS-BD and 94.5% (52/55) in ERCP (P = 0.49). Lower rates of overall adverse events (6.3% vs 19.7%, P = 0.03) including post-procedure pancreatitis (0 vs 14.8%), reintervention (15.6% vs 42.6%), and higher rate of stent patency (85.1% vs 48.9%) were observed with EUS-BD. EUS-BD was also associated with more preserved quality of life (QOL) than transpapillary stenting after 12 weeks of the procedure.Conclusions: This study demonstrated comparable technical and clinical success rates between EUS-BD and ERCP in relief of malignant distal biliary obstruction. Substantially longer duration of patency coupled with lower rates of adverse events and reintervention, and more preserved QOL were observed with EUS-BD (cris.nih.go.kr, Identifier: KCT0001396, https://cris.nih.go.kr/cris/search/search_result_st01_en.jsp?seq=9716amp:ltype=amp:rtype=). [ABSTRACT FROM AUTHOR]

Background and Aims: Immunoglobulin G4‐related sclerosing cholangitis (IgG4‐SC) is considered a biliary manifestation of IgG4‐related diseases. However, there has been a controversy on the clinical outcomes according to the location of the involved bile duct. We therefore compared the clinical outcomes and long‐term prognosis of IgG4‐SC with proximal bile duct involvement (proximal IgG4‐SC) and IgG4‐SC with distal bile duct involvement (distal IgG4‐SC). Methods: We reviewed the data of patients with IgG4‐SC that were prospectively collected at 10 tertiary centers between March 2002 and October 2020. Clinical manifestations, outcomes, association with autoimmune pancreatitis (AIP), steroid‐responsiveness, and relapse of IgG4‐SC were evaluated. Results: A total of 148 patients (proximal IgG4‐SC, n = 59; distal IgG4‐SC, n = 89) were analyzed. The median age was 65 years (IQR, 56.25–71), and 86% were male. The two groups were similar in terms of jaundice at initial presentation (51% vs 65%; P = 0.082) and presence of elevated serum IgG4 (66% vs 70%; P = 0.649). The two groups showed significant differences in terms of steroid‐responsiveness (91% vs 100%; P = 0.008), association with AIP (75% vs 99%; P = 0.001), and occurrence of liver cirrhosis (9% vs 1%; P = 0.034). During a median follow‐up of 64 months (IQR, 21.9–84.7), the cumulative relapse‐free survival was significantly different between the two groups (67% vs 79% at 5 years; P = 0.035). Conclusions: Relapse of IgG4‐SC frequently occurred during follow‐up. Proximal IgG4‐SC and distal IgG4‐SC had different long‐term outcomes in terms of steroid‐responsiveness, occurrence of liver cirrhosis, and recurrence. It may be advantageous to determine the therapeutic and follow‐up strategies according to the location of bile duct involvement. [ABSTRACT FROM AUTHOR]

Background and Aims: A fully covered self‐expandable metal stent (FCSEMS) has recently been applied in the management of chronic pancreatitis patients with pancreatic strictures. However, related long‐term effects remain unclear. This study aimed to evaluate the long‐term outcomes of FCSEMS placement in chronic pancreatitis patients with refractory strictures. Method: We retrospectively reviewed our database for patients undergoing FCSEMS placement for refractory pancreatic strictures between September 2008 and December 2010. The main outcomes were technical, radiological, and clinical success, as well as recurrence and adverse events. Results: A total of 35 patients were included. Technical success was achieved in all patients. The median FCSEMS indwelling time was 3.2 months (interquartile range [IQR], 3.0–4.9 months). Radiological success was achieved in all patients (complete, n = 2; partial, n = 33). Clinical success was achieved in 29 patients (82.9%; complete analgesic cessation, n = 19; analgesic reduction >50%, n = 11). During the median follow‐up of 136 months, (IQR, 85.8–145.5 months), eight patients (22.9%) experienced recurrence. The median interval from stent removal to recurrence was 24.9 months (IQR, 11.3–30.3 months). Biliary obstruction, an early adverse event, occurred in two patients (5.7%); the late adverse event stent‐induced de novo stricture was observed in 17 patients (48.6%). Conclusions: Our findings suggest that an FCSEMS is effective for relieving refractory strictures in chronic pancreatitis. However, FCSEMSs were associated with stent‐induced de novo strictures in nearly half of the patients. Prospective studies are required to further evaluate the long‐term efficacy and safety of FCSEMSs in chronic pancreatitis. [ABSTRACT FROM AUTHOR]

Background: Recently, the duodenum has garnered interest for its role in treating metabolic diseases, including type 2 diabetes (T2DM). Multiple sessions of external photobiomodulation (PBM) in previous animal studies suggested it resulted in improved hyperglycemia, glucose intolerance, and insulin resistance with a multifactorial mechanism of action, despite the target organ of PBM not being clearly proven. This study aimed to determine whether a single session of a duodenal light-emitting diode (LED) PBM may impact the T2DM treatment in an animal model. Methods: Goto–Kakizaki rats as T2DM models were subjected to PBM through duodenal lumen irradiation, sham procedure, or control in 1-week pilot (630 nm, 850 nm, or 630/850 nm) and 4-week follow-up (630 nm or 630/850 nm) studies. Oral glucose tolerance tests; serum glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide, and insulin levels; liver chemistry and histology; and gut microbiome in the PBM, sham control, and control groups were evaluated. Results: In the 1-week study, duodenal dual-wavelength (D, 630/850 nm) LED PBM showed improved glucose intolerance, alkaline phosphatase and cholesterol levels, and weight gain than other groups. The D-LED PBM group in the 4-week study also showed improved hyperglycemia and liver enzyme levels, with relatively preserved pancreatic islets and increased serum insulin and GLP-1 levels. Five genera (Bacteroides, Escherichia, Parabacteroides, Allobaculum, and Faecalibaculum) were significantly enriched 1 week after the D-LED PBM. Bacteroides acidifaciens significantly increased, while Lachnospiraceae significantly decreased after 1 week. Conclusion: A single session of D-LED PBM improved hyperglycemia and hepatic parameters through the change of serum insulin, insulin resistance, insulin expression in the pancreatic β-cells, and gut microbiome in T2DM animal models. [ABSTRACT FROM AUTHOR]

Background and Aim: EB‐RFA with self‐expandable metal stent (SEMS) may improve the stent patency and patient survival in malignant extrahepatic biliary obstruction. However, there are few studies on the role of EB‐RFA for malignant hilar obstruction (MHO). This study aimed to assess the feasibility, efficacy, and safety of EB‐RFA for MHO. Methods: We retrospectively compared the stent patency and survival among 79 consecutive patients with MHO who underwent bilateral uncovered SEMS placement without and with EB‐RFA between April 2016 and January 2020. Results: Fifty‐one patients (64.6%) underwent SEMS placement alone (stent alone group), whereas 28 (35.4%) underwent SEMS placement after EB‐RFA (RFA‐stent group). All procedures were successful (100%). During follow‐up, stent occlusion occurred in 59 patients (74.7%), of which 40 (78.4%) and 19 (67.9%) were in the stent alone and RFA‐stent groups, respectively. There was no difference in stent patency (192 ± 39.2 days vs 140 ± 53.7 days, P = 0.41) and survival (311 ± 24.7 days vs 311 ± 46.9 days, P = 0.73) between the stent alone and RFA‐stent groups. Multivariate cox analysis showed a hazard ratio (HR) of 2.892 (1.579–5.294, P = 0.001) for stent occlusion in patients who did not receive chemotherapy. EB‐RFA had no significant effect on stent occlusion (HR, 1.150, 0.644–2.053, P = 0.636). Conclusions: SEMS placement after EB‐RFA in MHO was not associated with improvement in the stent patency or patient survival. Further prospective randomized studies are necessary to establish the effectiveness of EB‐RFA with stents in MHO. [ABSTRACT FROM AUTHOR]

The article focuses on the case of a 67 year old man who reported to physicians with complaints of fatigue, fever and cramping abdominal pain. A discussion of an examination which was performed on the patient, and of a computed tomographic scan which was performed on the patient and revealed dilation of the common bile duct, is presented. A duodenoscopy which was performed on the patient and revealed the presence of leaf shaped worms called Clonorchis sinensis is discussed. The patient's treatment and recovery are reviewed.

Background and aims: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is frequently used for the preoperative histologic diagnosis of pancreatic cancer. However, debate continues regarding the clinical merits of preoperative EUS-FNA for the management of resectable pancreatic cancer. We aimed to evaluate the benefits and safety of preoperative EUS-FNA for resectable distal pancreatic cancer. Methods: The medical records of 304 consecutive patients with suspected distal pancreatic cancer who underwent EUS-FNA were retrospectively reviewed to evaluate the clinical benefits of preoperative EUS-FNA. We also reviewed the medical records of 528 patients diagnosed with distal pancreatic cancer who underwent distal pancreatectomy with or without EUS-FNA. The recurrence rates and cancer-free survival periods of patients who did or did not undergo preoperative EUS-FNA were compared. Results: The diagnostic accuracy of preoperative EUS-FNA was high (sensitivity, 87.5%; specificity, 100%; positive predictive value 100%; accuracy, 90.7%; negative predictive value, 73.8%). Among patients, 26.7% (79/304) avoided surgery based on the preoperative EUS-FNA findings. Of the 528 patients who underwent distal pancreatectomy, 193 patients received EUS-FNA and 335 did not. During follow-up (median 21.7 months), the recurrence rate was similar in the two groups (EUS-FNA, 72.7%; non-EUS-FNA, 75%; P = 0.58). The median cancer-free survival was also similar (P = 0.58); however, gastric wall recurrence was only encountered in the patients with EUS-FNA (n = 2). Conclusion: Preoperative EUS-FNA is not associated with increased risks of cancer-specific or overall survival. However, clinicians must consider the potential risks of needle tract seeding, and care should be taken when selecting patients. [ABSTRACT FROM AUTHOR]

Abstract: Pancreatic cancer may present as a peri-arterial soft tissue cuff (PSTC) around the superior mesenteric artery or celiac axis without an identifiable pancreatic mass. We evaluated the diagnostic yield of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in patients with a PSTC without definite pancreas involvement and those with a typical pancreatic mass. The patients who underwent EUS-FNA of a PSTC without pancreatic involvement were prospectively enrolled. The patients who underwent EUS-FNA for a pancreatic mass were recruited as a control group. A total of 224 patients underwent 247 EUS-FNAs. Among the 13 patients with a PSTC, 11 were positive for malignancy as determined by EUS-FNA, with 5 diagnosed after the first session and 6 after the second session. The diagnostic yield of PSTCs by EUS-FNA was significantly lower than that for typical pancreatic masses (65% vs. 87%, p = 0.02). An on-site cytopathologist and repeated EUS-FNA are recommended to improve the diagnostic accuracy of this disease entity. [Copyright &y& Elsevier]

Background/Aims: To evaluate the clinical usefulness of endoscopic biliary drainage (EBD) in patients with hepatocellular carcinoma (HCC). Methods: A total of 111 jaundiced patients underwent attempted EBD for relief of HCC-related biliary stricture at our hospital over a 5-year period and all were included in the intention-to-treat (ITT) analysis. Results: After an endoscopic attempt at drainage, 46 (41.4%) of the 111 patients achieved a favorable response. Biliary cannulation failed in 5 patients. Child-Pugh class C, portal vein thrombosis and severe hyperbilirubinemia were negatively correlated with a favorable EBD response. In the ITT population, 40 (87.0%) of the favorable responders received further treatment for HCC, >2 (3.1%) of the unfavorable responders (p < 0.001). The median survival time for ITT patients with and without a favorable response to EBD was 8.7 and 1.3 months, respectively (p < 0.001). Cox's model showed that a favorable EBD response was an independent predictor of longer survival (hazard ratio 0.20, p < 0.001). Conclusions: For HCC patients with tumor-related biliary obstruction, predictors of effective endoscopic palliation of cholestasis were relatively mild hyperbilirubinemia and preserved liver function and intact portal vein flow. A favorable EBD response was associated with longer survival outcomes. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background and Aim: While recent evidences support endoscopic resection as curative in ampullary tumors with high‐grade intraepithelial neoplasia, only small case series have reported endoscopic management of early‐stage ampullary cancer; thus, radical surgery remains the only accepted treatment modality. We evaluated the long‐term outcomes of early ampullary adenocarcinoma administered endoscopic management. Methods: We retrospectively reviewed electronic medical records of 715 patients undergoing endoscopic papillectomy (EP) in a single tertiary medical center in Korea in 2004–2016. We included patients incidentally diagnosed with early‐stage adenocarcinoma (Tis and T1a, American Joint Committee on Cancer 8th edition) after EP and with >2 years of follow‐up data and analyzed their demographics, histopathologic data, and clinical outcomes. Results: Among 70 total patients in the EP‐alone (n = 42) and subsequent surgery (n = 28) groups, we observed no significant differences in demographics or tumor size (2.0 ± 0.6 vs 1.9 ± 0.5 cm, P = 0.532), histologic grade (P = 0.077), tumor extent (P = 1.000), lymphovascular invasion (2.4% vs 10.7%, P = 0.344), or complete resection rates (57.1% vs 57.1%, P = 1.000) between groups. Adenocarcinoma lesions were larger in the subsequent surgery group (0.7 ± 0.5 vs 1.1 ± 0.7 cm, P = 0.002). The EP‐alone group received more additional ablative treatment (42.9% vs 14.3%, P = 0.024). The 5‐year disease‐free and cancer‐free survival rates were 79.1% vs 87.4% (P = 0.111) and 93.5% versus 87.4% (P = 0.726), respectively, and did not differ significantly between groups. Conclusions: Endoscopic papillectomy followed by endoscopic surveillance showed long‐term outcomes comparable with surgical resection for early ampullary cancer and maybe curable alternative to surgery for incidentally found early‐stage ampullary cancer, especially in patients unfit for or refusing radical surgery. [ABSTRACT FROM AUTHOR]

The literature survey reveals that condensation or evaporation study of R-404A alternative refrigerants are lacking. In this study, four R-404A alternative refrigerants - two short term refrigerants (GWP 100 ≤ 2500: R-448A, R-449A) and two long term refrigerants (GWP 100 ≤ 150: R-455A, R-454C) - including R-404A (GWP 100 = 3922) were tested under condensation condition. Test range included mass flux from 80 to 400 kg m−2s−1, vapour quality from 0.2 to 0.8. Test tube had 5.6 mm inne diameter. Results showed that, at a low mass flux, heat transfer coefficients of the alternative refrigerants were approximately the same as those of R-404A. On the other hand, at a high mass flux of 400 kg m−2s−1, heat transfer coefficients of the alternative refrigerants were higher than those of R-404A. The reason was attributed to the balance of superior thermal properties, which were beneficial, and larger temperature glide, which were malign, of the alternative refrigerants compared with those of R-404A. Pressure drops of alternative refrigerants were larger than those of R-404A. Furthermore, long term refrigerants (R-454C, R-455A) yielded larger pressure drops than short term refrigerants (R-448A, R-449A), probably due to the influence of vapour density. Furthermore, data are compared with predictions by existing correlations. [ABSTRACT FROM AUTHOR]

Objective. Few studies have assessed the diagnostic efficacy of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and/or trucut biopsy (TCB) in patients with rectal and perirectal lesions. We aimed to evaluate the diagnostic utility of EUS-FNA and/or TCB in patients with rectal and perirectal lesions. We also assessed their influence on the management and clinical course of these patients. Material and methods. We performed EUS-FNA and/or TCB in 11 consecutive patients (4 men and 7 women, 33-69 years) with rectal and perirectal lesions for whom conventional diagnostic tools could not provide definitive diagnoses. Patients with definite intraluminal cancer were excluded. Results. The 11 patients underwent 12 procedures, with 9 being EUS-FNA alone and 3 being EUS-FNA and TCB. Seven patients had rectal lesions and four had perirectal lesions. Initial EUS-FNA and/or TCB established a diagnosis of malignancy in five patients and of benign lesions in four. EUS-FNA plus TCB confirmed malignant lymphoma after diagnostic failure of initial EUS-FNA in one patient. In one other patient with suspicious secondary linitis plastica, EUS-FNA could not establish a definitive diagnosis. Correct diagnoses were obtained in 10 out of 11 patients who underwent EUS-FNA and/or TCB. EUS-FNA and/or TCB changed clinical courses, which included avoidance of unnecessary surgeries, having a chance of anal sphincter-saving surgeries, and timely administration of chemotherapy. No serious complications related to the use of EUS-FNA or TCB were evident. Conclusion. EUS-FNA and/or TCB are useful in the diagnostic evaluation of and appropriate therapeutic plan in patients with rectal and perirectal lesions. [ABSTRACT FROM AUTHOR]

Objective. To compare natural course and treatment results of various types of choledochal cysts. Material and methods. Complication rate in treated (T) and natural course in not treated (NT) patients with choledochal cysts were compared. The level of bilioenteric anastomosis after cyst resection was categorized and their post-procedure courses were analyzed. Results. A total of 204 patients (T, 174; NT, 30) were included. Patients with initial malignancies were excluded from the outcome analysis ( n = 13). Of the remaining 191 patients, the mean follow-up time was 35.9 months (range 6−310.7 months). Biliary stricture was the most troublesome post-operative complication, and occurred in 10 patients (6.1%). It occurred significantly more frequently in the above hilar anastomosis group than in at or below ( p-trend = 0.017), and also with older age ( p-trend = 0.019). Common bile duct stone was the most frequent adverse event among NT (42.9%). Overall, there were fewer complications among treated patients (T, 17.2%; NT, 67.9%; p < 0.001). Anomalous pancreaticobiliary union (APBU) was present in 69 patients (37.5%), which was associated with higher prevalence of carcinoma (APBU-present, 13%; APBU-absent, 3.5%; p = 0.019). No malignancy developed in both T and NT groups during follow-up. Conclusions. This study suggests, that even asymptomatic choledochal cysts should be treated, not only for prevention of malignancies, but also to lower the future adverse events. Bilioenteric anastomosis at larger caliber duct is recommended for prevention of post-operative biliary strictures. [ABSTRACT FROM AUTHOR]

In this paper, Energy Flow Boundary Element Method (EFBEM) was developed to predict the vibration behavior of one- and two-dimensional structures in the medium-to-high frequency ranges. Free Space Green functions used in the method were obtained from EFA energy equations. Direct and indirect EFBEMs were formulated for both one- and two-dimensional cases, and numerically applied to predict the energy density and intensity distributions of simple Euler-Bernoulli beams, single rectangular thin plates, and L-shaped thin plates vibrating in the medium-to-high frequency ranges. The results from these methods were compared with the EFA solutions to verify the EFBEM. [ABSTRACT FROM AUTHOR]

Abstract: The tripartite motif (TRIM) protein, TRIM5α, restricts infection by particular retroviruses. Many TRIM proteins form cytoplasmic bodies of unknown function. We investigated the relationship between cytoplasmic body formation and the structure and antiretroviral activity of TRIM5α. In addition to diffuse cytoplasmic staining, the TRIM5α proteins from several primate species were located in cytoplasmic bodies of different sizes; by contrast, TRIM5α from spider monkeys did not form cytoplasmic bodies. Despite these differences, all of the TRIM5α proteins exhibited the ability to restrict infection by particular retroviruses. Treatment of cells with geldanamycin, an Hsp90 inhibitor, resulted in disappearance or reduction of the TRIM5α-associated cytoplasmic bodies, yet exerted little effect on the restriction of retroviral infection. Studies of green fluorescent protein-TRIM5α fusion proteins indicated that no TRIM5α domain is specifically required for association with cytoplasmic bodies. Apparently, the formation of cytoplasmic bodies is not required for the antiretroviral activity of TRIM5α. [Copyright &y& Elsevier]

BACKGROUND : Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has been increasingly used for the management of various solid pancreatic tumors. This study aimed to evaluate the feasibility and safety of EUS-RFA for serous cystic neoplasms (SCNs). METHODS : 13 patients with microcystic SCNs with honeycomb appearance underwent EUS-RFA using a 19-gauge RFA needle. Before ablation, cystic fluid was aspirated until a thin layer of fluid remained. RESULTS : EUS-RFA was successful in all patients. Seven patients underwent a single session and the remaining six patients underwent a second session of EUS-RFA. One patient (7.7 %) experienced self-limited abdominal pain after EUS-RFA. During a median follow-up period of 9.21 months (interquartile range [IQR] 5.93 - 15.38), the median volume of the SCNs decreased from 37.82 mL (IQR 15.03 - 59.53) at baseline to 10.95 mL (IQR 4.79 - 32.39) at the end of follow-up. A radiologic partial response was achieved in eight patients (61.5 %). CONCLUSIONS : EUS-RFA is technically feasible and showed an acceptable rate of adverse events for patients with SCNs. A long-term follow-up study is required to evaluate the efficacy of EUS-RFA. [ABSTRACT FROM AUTHOR]

In this preliminary report, 3 mini-LED chips (2 with side and 1 with forward firing) a with 2.5-mm diameter and 5-mm diffuser length catheter were used for administering PDT in pancreatic cancer xenografts (Fig. 2 In vivo efficacy of interstitial-photodynamic therapy (i-PDT) in BxPC3 tumor-bearing mice within 15 days in different groups treated with Photofrin (Phf) and chlorin e6 (Ce6). Both LED-based i-PDT (100 J/cm2) with Photofrin and Ce6 had better suppression of tumor growth than in other groups. [Extracted from the article]

Introduction: For unresectable hilar obstruction, restoring and maintaining biliary ductal patency are crucial for improved survival and quality of life. The endoscopic placement of stents is now a mainstay of its treatment, and bilateral stenting is effective for biliary decompression. This study aimed to determine the clinical outcomes of bilateral metal stent placement using large cell-type stents and the clinical predictors of stent dysfunction in patients with malignant hilar obstruction. Methods: We performed a retrospective analysis of patients who underwent bilateral metal stent placement using two large cell-type stents at two academic teaching hospitals between September 2017 and February 2019. The primary outcome was stent dysfunction. Secondary outcomes included predictors related to stent dysfunction and overall survival. Results: The study included 87 patients who underwent bilateral metal stent placement for malignant hilar obstruction. Technical success and clinical success were achieved in 80 patients (92.0%) and 83 patients (95.4%), respectively. During the follow-up period (median: 201, range: 18–671 days), stent dysfunction occurred in 42 patients (48.3%), and the median stent patency was 199 days (95% confidence interval [CI]: 181–262). In univariate analysis, age, cholangitis before stent insertion, and subsequent chemotherapy were found to be associated with the cumulative risk of stent dysfunction. In multivariate analysis, cholangitis before stent insertion (hazards ratio [HR]: 2.26, 95% CI: 1.216–4.209, P = 0.010) and subsequent chemotherapy (HR: 0.250, 95% CI: 0.130–0.482, P<0.001) remained as statically significant factors associated with the cumulative risk of stent dysfunction. The median overall survival was 288 days (95% CI: 230–327). Conclusion: The bilateral placement of large cell-type stents for malignant hilar obstruction was effective with high technical and clinical success rates and acceptable patency. Cholangitis before stent insertion was associated with shorter patency, and subsequent chemotherapy was associated with longer stent patency. [ABSTRACT FROM AUTHOR]

Solobacterium moorei is an anaerobic gram-positive bacillus that rarely causes bacteremia. Herein, we report a case of S. moorei bacteremia associated with acute cholangitis in a patient without malignancy. The patient had a history of chronic pancreatitis with pancreaticogastrostomy and presented with fever and abdominal pain. Computed tomography scans showed acute cholangitis and S. moorei identified in blood cultures were confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry and 16S rRNA sequencing. The patient was successfully treated with endoscopic retrograde biliary drainage and antibiotics including meropenem and piperacillin-tazobactam. • Solobacterium moorei is an anaerobic gram-positive bacillus that rarely causes bacteremia. • We report a case of S. moorei bacteremia associated with acute cholangitis in a patient without malignancy in Korea. • S. moorei identified in blood cultures were confirmed by MALDI-TOF MS and 16S rRNA sequencing. • The patient was successfully treated with endoscopic retrograde biliary drainage and antibiotics. [ABSTRACT FROM AUTHOR]

Background and Aims: Segregated right intrahepatic duct dilatation (IHD) results from complete obstruction of the biliary tract proximal to the hilar level. We aimed to evaluate long‐term efficacy and safety of endoscopic ultrasound (EUS) hepaticoduodenostomy (HDS) in segregated right IHD. Methods: Consecutive patients who had undergone EUS‐guided HDS with a fully covered self‐expandable metal stent (FCSEMS) in an academic tertiary center were recruited. All patients had segregated right hepatic duct and failed drainage by endoscopic retrograde cholangiopancreatography (ERCP). Demographic data, endoscopic findings, procedure details, and outcome data were extracted from a prospectively maintained database. Results: From 2013 to 2017, there were 35 patients who had undergone EUS‐guided HDS with a median follow‐up duration of 169 (3–2091) days. Malignancy accounted for 71.4% of the ductal segregation, followed by surgical complication (17.1%). Technical and clinical success rate was 97.1% and 80%, respectively. Early adverse event (AE) happened in seven patients (20%), two of them required endoscopic reintervention, and no percutaneous transhepatic biliary drainage (PTBD) or surgery was performed because of AE. The median stent patency duration was 331 (3–1202) days. The median duration of fistula tract keeping was 1280 (3–1280) days. There was no significant difference in terms of patency rate with respect to whether the underlying pathology was benign or malignant (P = 0.776). EUS‐guided HDS for right posterior sectional duct segregation was associated with higher 3‐month stent patency rate when compared with right anterior sectional duct (79.1% vs 38.1%, P = 0.012). Conclusion: Endoscopic ultrasound‐guided HDS with an FCSEMS appears to be a safe and effective treatment as a viable alternative option to PTBD after failed ERCP. It creates a durable and reliable fistula tract for permanent access to an isolated ductal system, and this application deserves more attention. [ABSTRACT FROM AUTHOR]

A high-speed residue-free transfer method using PDMS (polydimethylsiloxane) stamp and water infiltration between graphene and a hydrophilic surface is reported. Monolayer graphene was transferred from an enhanced fluorinated Al 2 O 3 surface using PDMS. Water infiltration dramatically reduced the time required to separate the graphene from the Al 2 O 3 substrate to a few minutes. The graphene was then successfully transferred to a target substrate (SiO 2) using the PDMS stamp. Atomic force microscopy and lateral force microscopy was used to confirm the absence of residue on the transferred graphene surface. • High-speed residue-free transfer using UV-hardened PDMS stamp combined with increased water infiltration. • CF 4 /O 2 plasma-treatment enhanced hydrophilicity of Al 2 O 3 over a SiO 2. • Enhanced water infiltration boosted the separation of graphene from the substrate with the increased hydrophilicity. • UV treatment of PDMS reduced the residues of transferred graphene. [ABSTRACT FROM AUTHOR]

Background: Patients with borderline resectable pancreatic cancer (BRPC) have poor prognosis with upfront surgery.Methods: This was a single-arm Phase 2 trial for clinical and biomarker analysis. The primary endpoint is 1-year progression-free survival (PFS) rate. Patients received 8 cycles of neoadjuvant modified (m) FOLFIRINOX. Up to 6 cycles of gemcitabine were given for patients who underwent surgery. Plasma immune cell subsets were measured for analysing correlations with overall survival (OS).Results: Between May 2016 and March 2018, 44 chemotherapy- and radiotherapy-naïve patients with BRPC were included. With neoadjuvant mFOLFIRINOX, the objective response rate was 34.1%, and curative-intent surgery was done in 27 (61.4%) patients. With a median follow-up duration of 20.6 months (95% confidence interval [CI], 19.7-21.6 months), the median PFS and OS were 12.2 months (95% CI, 8.9-15.5 months) and 24.7 months (95% CI, 12.6-36.9), respectively. The 1-year PFS rate was 52.3% (95% CI, 37.6-67.0%). Higher CD14+ monocyte (quartile 4 vs 1-3) and lower CD69+ γδ T cell (γδ TCR+/CD69+) levels (quartiles 1-3 vs 4) were significantly associated with poor OS (p = 0.045 and p = 0.043, respectively).Conclusions: Neoadjuvant mFOLFIRINOX followed by postoperative gemcitabine were feasible and effective in BRPC patients. Monocyte and γδ T cells may have prognostic implications for patients with pancreatic cancer. ClinicalTrials.gov identifier: NCT02749136. [ABSTRACT FROM AUTHOR]

Background and Aim: Many post‐ERCP pancreatitis (PEP) risk factors, including pancreatic duct cannulation, have been identified; however, whether the number of repeated and unintentional wire placements (WPs) in the pancreatic duct during wire‐guided cannulation affects PEP risk is unknown. We aimed to identify the effects of repeated WP in the pancreatic duct and other potential risk factors on PEP incidence. Methods: We retrospectively analyzed 877 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP). We examined potential patient‐related and procedure‐related risk factors, and PEP incidence by univariable and multivariable logistic regression analyses. Results: Thirty‐four patients (3.9%) had PEP. Univariable analysis revealed younger age, malignant common bile duct or ampulla of Vater stricture, two or more episodes of WPs in the pancreatic duct, and metal biliary stent as risk factors for PEP. Following multivariable analysis, two or more episodes of WPs in the pancreatic duct and metal biliary stent remained in the final model. PEP did not increase significantly in case of a one episode of WP (4.0%) compared with no episode of WP in the pancreatic duct (2.7%). However, patients with two episodes of WPs had 8.0% incidence and three or more episodes of WPs had 14.3%. Conclusions: A WP in the pancreatic duct and a metal biliary stent were associated with increased PEP incidence in patients undergoing ERCP. As for the pancreatic duct wire cannulation, two or more WPs considerably increased PEP incidence. This suggests that preventive measures or alternative procedures might be considered in patients with such cases during and after ERCP. [ABSTRACT FROM AUTHOR]

Background and Aim: The clinical significance of incidental pancreatic cystic lesions (PCLs) remains unclear in those that are not accompanied by worrisome features or high‐risk stigmata. We aimed to investigate the natural course of PCLs without any risk features and examine the clinical factors associated with their progression. Methods: We conducted a retrospective cohort study of 427 patients with PCLs, which were incidentally detected by computed tomography between January 2003 and December 2012. Progression of PCLs without any risk features and the clinical factors associated with their progression were investigated. The length of time to significant growth was also evaluated. Results: Ninety‐four (22.0%) of the 427 patients had asymptomatic PCLs that showed significant growth after a median surveillance period of 5.3 years; approximately 27.7% of the patients showed significant size changes in the first 5 years, while the remaining 72.3% showed significant changes after 5 years. The cumulative rate of patients with significant growth was associated with initial cyst size and high body mass index. In the growth group, additional treatments were required for 12 patients, one of whom developed malignancy. Four patients in the stable group underwent additional treatment and showed no malignant change. Conclusions: One‐fifth of the asymptomatic PCLs significantly increased in size after a long‐term follow‐up period, which was associated with initial cyst size and obesity. The size of PCLs mostly increased after 5 years; although the malignancy risk of PCLs was low, it was still a concern. [ABSTRACT FROM AUTHOR]

In biliary tract cancer (BTC), standard chemotherapy has limited benefit and no molecular targeted agents have been approved. This study investigated the genetic profile of BTC to identify potential new therapeutic targets and predictive biomarkers. Targeted exome sequencing was performed for 124 patients with BTC [gallbladder cancer (GBC), 25; intrahepatic cholangiocarcinoma (ICC), 55; extrahepatic cholangiocarcinoma (ECC), 44]. Survival analysis was performed in 112 patients who received palliative chemotherapy for locally unresectable or metastatic disease. Genetic alterations were observed in 104 patients (83.8%); the most commonly mutated genes were TP53 (44.4%), KRAS (29.0%), ARID1A (12.1%) and IDH1 (9.7%). IDH1/2 mutations appeared more frequently in ICC (23.6%, P = 0.0002) than in GBC (4.0%) or ECC (2.3%), while ERBB2 / 3 mutations were found only in GBC (20.0%) and ECC (11.4%). Patients harbouring TP53 mutations had shorter overall survival (OS; median 15.2 vs. 37.8 months, P = 0.018), while IDH1 mutations showed a tendency for longer progression-free survival (PFS; 10.6 vs. 6.1 months, P = 0.124). Potentially actionable genetic alterations were found in 54.8%, and 7.1% received appropriate molecular targeted therapy in the clinical trial setting. Germline or somatic mutations in DNA damage repair (DDR) genes were found in 63.5% of patients and were significantly associated with longer PFS (6.9 vs. 5.7 months, P = 0.013) and OS (21.0 vs. 13.3 months, P = 0.009) in patients who received first-line platinum-containing chemotherapies (n = 88). A subgroup of patients with BTC may benefit from targeted therapy by the aid of genetic information. In particular, DDR alterations may be a predictive biomarker for response to platinum-containing chemotherapy in patients with BTC. • We examined genetic landscape of biliary tract cancer with targeted sequencing. • Certain genetic mutations were associated with clinical outcomes. • More than half of patients harboured at least one potentially actionable alteration. • DNA damage repair gene alterations were associated with a better response to platinum-based treatment. [ABSTRACT FROM AUTHOR]

Background: Recently, laparoscopic distal pancreatectomy (LDP) has become the standard procedure for resection of left-sided pancreatic tumors. Fluid collection (FC) at the resection margin of the pancreatic stump after LDP is a frequent radiological finding. However, there have been few treatment guidelines and the optimal management for this clinical finding is unclear. The aim of present study is to define the incidence of FC and suggest the optimal management for FC after LDP.Methods: A total of 1227 patients who underwent LDP between March 2005 and December 2015 were collected. FC was considered present when the longest diameter of the lesion on CT scan was > 3 cm.Results: A follow-up with at least two CT image was available for 1102 patients. Of these, 689 (62.5%) patients showed initial fluid collection (IFC) at the pancreas resection site in immediate postoperative CT. IFC (+) group had higher proportion of men, BMI, and higher rate of concomitant splenectomy than IFC (-) group. Among patients with FC after LDP, the treatment group had more frequent leukocytosis and accompanying symptoms than the observation group. Seventy-seven patients underwent therapeutic interventions for FC after LDP. Among them, 55 (71.4%) patients underwent endoscopic ultrasonography-guided gastrocystostomy (EUS-GC). EUS-GC group had a higher success rate (85.6 vs. 63.6%, p < 0.033) and shorter hospital stay after the intervention (5.2 vs. 13.3 days, p < 0.001) than those who underwent other procedures.Conclusions: High BMI, male, and concomitant splenectomy contribute to the occurrence of FC after LDP. In most cases, FC after LDP resolved spontaneously over time with observation. The patients with symptomatic FC ultimately required treatment. EUS-GC is the optimal intervention therapy for FC after LDP. [ABSTRACT FROM AUTHOR]

In this letter, a higher‐order‐mode coupler using waveguide for multimode monopulse satellite tracking and signal processing schemes handling the signal from the higher‐order‐mode coupler are proposed. The proposed higher‐order‐mode coupler uses TM01 mode for compactness and weight reduction, making it suitable for OTM satellite tracking systems. The TM01 mode is extracted from the two H‐plane slots of the circular waveguide and then divided signals are combined through magic‐T structure. Also, the sum and difference radiation patterns of antenna applicable to monopulse satellite tracking are generated. A monopulse tracking data is extracted using the proposed signal processing schemes to the antenna radiation patterns. The influence of Doppler effect and noise is concerned to enhance tracking accuracy and sliding techniques are adopted to deal with an instantaneous tracking system. Designed X‐band higher‐order‐mode coupler of TM01 mode and signal processing schemes are expected to be used for all OTM monopulse satellite tracking systems. [ABSTRACT FROM AUTHOR]

Background and Aims: Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) is increasingly accepted as an effective treatment option in patients who require drainage for acute cholecystitis. A newly designed lumen-apposing metal stent (LAMS) has been introduced recently in this procedure. In this study, we evaluated the feasibility and safety of the newly designed LAMS in patients with acute cholecystitis who were unsuitable for cholecystectomy.Methods: Between Mar 2017 and Oct 2017, 22 patients with acute cholecystitis who were unsuitable for cholecystectomy underwent EUS-GBD with the newly designed LAMS. We evaluated the technical and clinical success and the adverse event profiles.Results: EUS-GBD with newly designed LAMS was technically and clinically successful in 21 of the 22 patients. EUS-GB stenting was performed at urgent setting in 17 patients, while 5 patients, who had undergone initial PTGBD, underwent EUS-GB stenting to remove PTGBD tube. The median procedure time was 11.5 (range 8.8-17.0) min. A late adverse event of stent occlusion developed in one patient. Stent migration was not observed during follow-up (median 318.0 days, range 39.0-398.0 days) and cumulative stent patency rate at 1 year was 95%.Conclusion: EUS-GBD with newly designed LAMS is feasible and shows acceptable safety profiles for both the urgent drainage of acute cholecystitis and elective internalization following PTGBD in patients with high surgical risk. [ABSTRACT FROM AUTHOR]

Background and Aim: Few studies compared endoscopic ultrasound (EUS)‐guided fine needle aspiration (EUS‐FNA) with endoscopic retrograde cholangiopancreatography (ERCP)‐based tissue sampling in terms of diagnostic accuracy in suspected malignant biliary obstruction. We evaluated and compared the diagnostic performance of EUS‐FNA and ERCP‐based tissue sampling. Methods: This multicenter study included 263 patients with suspected malignant biliary obstruction who underwent same‐session EUS and ERCP between 2012 and 2016. Results: Malignancies were confirmed in 239 patients (90.9%) and benign in 24 patients (9.1%). Overall diagnostic sensitivity and accuracy were 73.6% and 76.1% for EUS‐FNA, 56.5% and 60.5% for ERCP, and 85.8% and 87.1% for EUS/ERCP combination. EUS‐FNA showed higher overall performances compared with ERCP (P < 0.001), whereas EUS/ERCP combination was superior to EUS‐FNA alone (P‐value < 0.001). EUS‐FNA showed higher sensitivity and accuracy compared with ERCP for pancreatic masses (n = 187, both P‐values < 0.001) but not for biliary lesions (n = 76, both P‐values = 0.847). Sensitivity and accuracy of EUS/ERCP combination were superior to those of EUS‐FNA for both pancreatic and biliary lesions (both P‐values < 0.001). For patients with large mass (≥ 4 cm), there was no significant differences between ERCP/EUS combination and EUS‐FNA (P‐value = 0.31). Conclusions: Same‐session EUS‐FNA and ERCP combination was superior to EUS‐FNA for both pancreatic masses and biliary lesions. Same‐session EUS/ERCP combination can be considered a proper diagnostic method for suspected malignant biliary obstruction regardless of the origin of lesions. On the other hand, EUS‐FNA alone was sufficient for diagnosis compared with EUS/ERCP combination in cases with large mass. Strategic diagnostic approach, according to clinical features of individual patient, is required. [ABSTRACT FROM AUTHOR]

Model-based systems engineering is becoming important and is being more widely used as the computing power is improved, because it can be extensively utilized for evaluating performances of vehicles with less effort and time than real-world tests. In this study, a port-based model technique is reviewed, especially for investigating the model connection between the transmission output and the final-drive input in vehicle powertrain models. Commercialized tools that model vehicle powertrains provide well-organized processes for users to connect conventional component models, but a confliction problem of connecting ports frequently arise when users develop their own models and integrate them into a vehicle system. In this study, several ideas to address the conflict issue have been reviewed, and an idea is implemented to solve the port conflict of the vehicle powertrain, and discussions about the method are provided. The idea is very useful especially when the powertrain model uses effort and flow signals to connect sub-component models. Simulation results show that the method produces accurate results and is fast enough, which requires additional calculation time less than 1 %, compared to an alternative method, and it is proved that it guarantees numerical stability in computations. The idea has been widely used in powertrain models, but the feasibility and the numerical stability have not been carefully investigated in the previous studies, so this study would be helpful for proving a basis to model users who develop new sub-component models. [ABSTRACT FROM AUTHOR]

Background: Radiofrequency ablation (RFA) has been increasingly employed in experimental and clinical settings for the management of pancreatic lesions. This study aimed to assess the safety and efficacy of endoscopic ultrasound (EUS)-guided RFA for benign solid pancreatic tumors.Methods: In a single-center, prospective study, 10 patients with benign solid pancreatic tumors underwent EUS-RFA. After the RFA electrode had been inserted into the pancreatic mass, the radiofrequency generator was activated to deliver 50 W of ablation power.Results: Among the 10 patients, 16 sessions of EUS-RFA were successfully performed. Diagnoses included nonfunctioning neuroendocrine tumor (n = 7), solid pseudopapillary neoplasm (n = 2), and insulinoma (n = 1); the median largest diameter of the tumors was 20 mm (range 8 - 28 mm). During follow-up (median 13 months), radiologic complete response was achieved in seven patients. Two adverse events (12.4 %; 1 moderate and 1 mild) occurred.Conclusions: EUS-RFA may be a safe and potentially effective treatment option in selected patients with benign solid pancreatic tumors. Multiple sessions may be required if there is a remnant tumor, and adverse events must be carefully monitored. [ABSTRACT FROM AUTHOR]