124 research outputs found

    Quantum measuring processes for trapped ultracold bosonic gases

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    The standard experimental techniques usually adopted in the study of the behaviour of ultracold atoms in optical lattices involve extracting the atom density profile from absorption images of the atomic sample after trap release. Quantum mechanically this procedure is described by a generalized measure (POVM); interference patterns found in absorption images suggest a generalized measure based on fixed-phase, coherent-like states. We show that this leads to an average atomic density which differs from the usually adopted one, obtained as the expectation value of the atom density operator in the many-body state.Comment: 11 pages, LaTe

    Noise induced current in a double-well trap

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    We study the behavior of cold atoms trapped in optical double well potentials in presence of noise, either generated by an external environment or by the trap itself. We show that quite in general the noise can induce a current between the two wells even when tunneling between the two wells is highly suppressed (Mott insulator phase). An engineered environment could provide a test ground for the behavior of such a current.Comment: 10 pages, LaTe

    Direct peroral cholangioscopy in the management of difficult biliary stones: a new tool to confirm common bile duct clearance. Results of a preliminary study

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    Background and aims: Endoscopic sphincterotomy (ES) with stone extraction is the standard treatment for choledocholithiasis. After stone retrieval, balloon-occluded cholangiography is generally performed to confirm bile duct clearance but can miss residual stones particularly in patients with residual small-sized stones, a large bile duct or pneumobilia. In addition, difficult common bile duct (CBD) stones requiring advanced endoscopic techniques for retrieval are a potential risk factor for choledocholithiasis recurrence. Methods: We performed a retrospective evaluation of a prospectively maintained procedures database. From July 2016 to December 2017, all patients with difficult CBD stones who underwent endoscopic retrograde cholangiopancreatography (ERCP) with papillary balloon dilation-assisted stone retrieval and subsequent direct per-oral cholangioscopy (DPOC) using standard gastroscopes to confirm CBD clearance were analyzed. Results: Thirty-six patients who underwent ERCP and DPOC were included. Technical success, defined as deep intubation of CBD with hepatic hilum visualization, was achieved in 31 of 36 patients (86%). During DPOC, residual CBD stones were visualized and removed in 7 of 31 patients (22.5%). After a mean of 241 +/- 56 days of follow-up post-DPOC, no serious adverse events were reported, and there was no evidence or suspicion of recurrent choledocholithiasis. Conclusions: Direct per-oral cholangioscopy immediately following difficult CBD stone removal was safe, feasible and accurate. In this setting, DPOC at the time of ERCP appears to be a very useful tool to achieve complete clearance of choledocholithiasis.info:eu-repo/semantics/publishedVersio

    Endoscopic ultrasound fine-needle biopsy vs fine-needle aspiration for lymph nodes tissue acquisition: A systematic review and meta-Analysis

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    Background: Endoscopic ultrasound (EUS)-guided tissue acquisition represents the choice of methods for suspected lymph nodes (LNs) located next to the gastrointestinal tract. This study aimed to compare the pooled diagnostic performance of EUS-guided fine-needle biopsy (EUS-FNB) and fine-needle aspiration (EUS-FNA) for LNs sampling. Methods: We searched PubMed/MedLine and Embase databases through August 2021. Primary outcome was diagnostic accuracy; secondary outcomes were sensitivity, specificity, sample adequacy, optimal histological core procurement, number of passes, and adverse events. We performed a pairwise meta-Analysis using a random-effects model. The results are presented as odds ratio (OR) or mean difference along with 95% confidence interval (CI). Results: We identified nine studies (1,276 patients) in this meta-Analysis. Among these patients, 66.4% were male; the median age was 67 years. Diagnostic accuracy was not significantly different between the two approaches (OR, 1.31; 95% CI, 0.81-2.10; P = 0.270). The accuracy of EUS-FNB was significantly higher when being performed with newer end-cutting needles (OR, 1.87; 95% CI, 1.17-3.00; P = 0.009) and in abdominal LNs (OR, 2.48; 95% CI, 1.52-4.05; P < 0.001) than that of EUS-FNA. No difference in terms of sample adequacy was observed between the two approaches (OR, 1.40; 95% CI, 0.46-4.26; P = 0.550); however, histological core procurement and diagnostic sensitivity with EUS-FNB were significantly higher than those with EUS-FNA (OR, 6.15; 95% CI, 1.51-25.07; P = 0.010 and OR, 1.87; 95% CI, 1.27-2.74, P = 0.001). The number of needle passes needed was significantly lower in the EUS-FNB group than in the EUS-FNA group (mean difference,-0.54; 95% CI,-0.97 to-0.12; P = 0.010). Conclusions: EUS-FNA and EUS-FNB perform similarly in LN sampling; however, FNB performed with end-cutting needles outperformed FNA in terms of diagnostic accuracy

    Microbiota Gut-Brain Axis in Ischemic Stroke: A Narrative Review with a Focus about the Relationship with Inflammatory Bowel Disease.

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    The gut microbiota is emerging as an important player in neurodevelopment and aging as well as in brain diseases including stroke, Alzheimer's disease, and Parkinson's disease. The complex interplay between gut microbiota and the brain, and vice versa, has recently become not only the focus of neuroscience, but also the starting point for research regarding many diseases such as inflammatory bowel diseases (IBD). The bi-directional interaction between gut microbiota and the brain is not completely understood. The aim of this review is to sum up the evidencesconcerningthe role of the gut-brain microbiota axis in ischemic stroke and to highlight the more recent evidences about the potential role of the gut-brain microbiota axis in the interaction between inflammatory bowel disease and ischemic stroke

    Methods for Drainage of Distal Malignant Biliary Obstruction after ERCP Failure: A Systematic Review and Network Meta‐Analysis

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    There is scarce evidence on the comparison between different methods for the drainage of distal malignant biliary obstruction (DMBO) after endoscopic retrograde cholangiopancreatography (ERCP) failure. Therefore, we performed a network meta‐analysis to compare the outcomes of these techniques. We searched main databases through September 2021 and identified five randomized controlled trials. The primary outcome was clinical success. The secondary outcomes were technical success, overall and serious adverse event rate. Percutaneous trans‐hepatic biliary drainage was found to be inferior to other interventions (PTBD: RR 1.01, 0.88– 1.17 with EUS‐choledochoduodenostomy (EUS‐CD); RR 1.03, 0.86–1.22 with EUS-hepaticogastrostomy (EUS‐HG); RR 1.42, 0.90–2.24 with surgical hepaticojejunostomy). The comparison between EUS‐HG and EUS‐CD was not significant (RR 1.01, 0.87–1.17). Surgery was not superior to other interventions (RR 1.40, 0.91–2.13 with EUS‐CD and RR 1.38, 0.88–2.16 with EUS‐HG). No difference in any of the comparisons concerning adverse event rate was detected, although PTBD showed a slightly poorer performance on ranking analysis (SUCRA score 0.13). In conclusion, all interventions seem to be effective for the drainage of DMBO, although PTBD showed a trend towards higher rates of adverse events

    Endoscopic ultrasound-guided ablation of solid pancreatic lesions: A systematic review of early outcomes with pooled analysis

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    Contains fulltext : 252157.pdf (Publisher’s version ) (Open Access)BACKGROUND: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is emerging as a complementary therapeutic approach for pancreatic solid masses. However, results of published data are difficult to interpret because of a retrospective design and small sample size. AIM: To systematically review data on EUS-RFA for solid lesions and to pool the results of the different experiences in order to provide more consistent evidence in terms of safety and efficacy. METHODS: A comprehensive systematic literature search on the main databases was performed to identify articles in which patients with pancreatic solid lesions underwent EUS-RFA. The primary outcomes were procedure-related adverse events (AEs) and mortality. Secondary outcomes were the technical success rate and the effects on primary tumor growth. Statistical analyses were performed using Stata version 14.0. RESULTS: In total, 14 studies were included, with 120 patients undergoing 153 ablations of 129 solid pancreatic lesions. The STARmed technology was used in seven studies, the Habib system in six studies, and the HybridTherm probe in one study. The pooled technical success rate was 99.0% (I (2): 25.82%). The pooled overall AE rate was 8.0% (I (2): 11.46%). Excluding mild AEs, the pooled rates of serious AEs was 1.0% (I (2): 0%). No mortality related to the procedure was reported. CONCLUSION: The present pooled analysis confirms the safety and feasibility of EUS-RFA

    Gastric peroral endoscopic pyloromyotomy for refractory gastroparesis: a systematic review of early outcomes with pooled analysis

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    Background and Aims: Gastroparesis (GP) is a chronic debilitating condition. Prior pyloric-targeted procedures are either invasive or have questionable efficacy. Gastric peroral pyloromyotomy (G-POEM) has been proposed as a minimally invasive approach. We performed a pooled analysis to evaluate the efficacy and safety of G-POEM for GP. Methods: Electronic databases (Medline, Scopus, EMBASE) were searched up to January 2019. Studies including patients who underwent G-POEM for GP were eligible. Procedural, clinical, and safety outcomes were assessed by pooling data with a random- or fixed-effect model according to the degree of heterogeneity to obtain a proportion with a 95% confidence interval. Results: Ten studies were eligible for inclusion (292 patients), and 2 of the 10 studies were prospective. Seven studies were performed in the United States, 2 in France, and 1 in China. Endoscopic pyloromyotomy was feasible in all patients. Significant symptomatic improvement was achieved after 83.9% of procedures (mean follow-up, 7.8 ± 5.5 months). When comparing the mean values of pre- and postprocedural scintigraphic evolution, there was a significant decrease of the residual percentage at 2 and 4 hours. The overall adverse events rate was 6.8%. Conclusions: G-POEM appears to be a promising approach for GP in terms of safety and efficacy outcomes in the short term
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