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[EN] This paper deals with an investigation of hexagonal W-Nb-O and W-V-Nb-O bronzes as catalysts for the one-pot oxidehydration of glycerol into acrylic acid. In a previous work, we reported that the best yield to acrylic acid obtained with the W-V-O bronze was 25%; in the current work, the incorporation of Nb in the tri-component bronze structure allowed us to obtain the best acrylic acid yield of 34%. The W-Nb-O bronze was an efficient acid catalyst for the dehydration of glycerol into acrolein - more selective than WO3 at temperatures lower than 300 degrees C -, whereas in the tri-component system the presence of V conferred to the catalyst the redox properties for the partial oxidation of acrolein into acrylic acid. The characterization of the catalysts confirmed the incorporation of Nb5+ in the hexagonal structure, and the generation of acid sites with enhanced strength compared to the bi-component W-V-O system. This also enhanced the stability of catalytic performance during short-term lifetime experiments. (C) 2012 Elsevier B.V. All rights reserved., CIRI (Centro Interdipartimentale per la Ricerca industriale, Universita di Bologna) Energia e Ambiente is acknowledged for the research grant assigned to Alessandro Chieregato. MIUR (Ministero dell'Universita e della Ricerca Scientifica) is acknowledged for the PhD grant to Stefania Guidetti (Progetto Giovani). MIPAAF (Ministero delle Politiche Agricole Alimentari e Forestali) is acknowledged for partially financing the project (Progetto Extravalore, PNR 2005-2007). Financial support from DGICYT in Spain (Project CTQ-2009-14495) and Generalitat Valenciana (ACOMP/2010/091) is gratefully acknowledged.

Endoscopic enteral stenting (ES) in malignant gastric outlet obstruction (GOO) is limited by high rates of stent obstruction. EUS-guided gastroenterostomy (EUS-GE) is a novel procedure that potentially offers sustained patency without tumor ingrowth/overgrowth. The aim of this study is to compare EUS-GE with ES in terms of (1) symptom recurrence and need for re-intervention, (2) technical success (proper stent positioning as determined via endoscopy and fluoroscopy), (3) clinical success (ability to tolerate oral intake without vomiting), and (4) procedure-related adverse events (AEs). Multicenter retrospective study of all consecutive patients who underwent either EUS-GE at four centers between 2013 and 2015 or ES at one center between 2008 and 2010. A total of 82 patients (mean age 66-years ± 13.5 and 40.2% female) were identified: 30 in EUS-GE and 52 in ES. Technical and clinical success was not significantly different: 86.7% EUS-GE versus 94.2% ES (p = 0.2) and 83.3% EUS-GE versus 67.3% ES (p = 0.12), respectively. Symptom recurrence and need for re-intervention, however, was significantly lower in the EUS-GE group (4.0 vs. 28.6%, (p = 0.015). Post-procedure mean length of hospitalization was comparable at 11.3 days ± 6.6 for EUS-GE versus 9.5 days ± 8.3 for ES (p = 0.3). Rates and severity of AEs (as per the ASGE lexicon) were also similar (16.7 vs. 11.5%, p = 0.5). On multivariable analysis, ES was independently associated with need for re-intervention (OR 12.8, p = 0.027). EUS-GE may be ideal for malignant GOO with comparable effectiveness and safety to ES while being associated with fewer symptom recurrence and requirements for re-intervention.

Background and aims: The ability to safely and effectively obtain sufficient tissue for pathologic evaluation by using endoscopic ultrasound (EUS) guidance remains a challenge. Novel designs in EUS needles may provide for improved ability to obtain such core biopsies. The aim of this study was to evaluate the diagnostic yield of core biopsy specimens obtained using a novel EUS needle specifically designed to obtain core biopsies. Patients and methods: Multicenter retrospective review of all EUS-guided fine-needle biopsies obtained using a novel biopsy needle (SharkCore FNB needle, Medtronic, Dublin, Ireland). Data regarding patient demographics, lesion type/location, technical parameters, and diagnostic yield was obtained. Results: A total of 250 lesions were biopsied in 226 patients (Median age 66 years; 113 (50 %) male). Median size of all lesions (mm): 26 (2 – 150). Overall, a cytologic diagnosis was rendered in 81 % specimens with a median number of 3 passes. When rapid onsite cytologic evaluation (ROSE) was used, cytologic diagnostic yield was 126/149 (85 %) with a median number of 3 passes; without ROSE, cytologic diagnostic yield was 31/45 (69 %, P = 0.03) with a median number of 3 passes. Overall, a pathologic diagnosis was rendered in 130/147 (88 %) specimens with a median number of 2 passes. Pathologic diagnostic yield for specific lesion types: pancreas 70/81 (86 %), subepithelial lesion 13/15 (87 %), lymph node 26/28 (93 %). Ten patients (10/226, 4 %) experienced adverse events: 4 acute pancreatitis, 5 pain, 1 fever/cholangitis. Conclusions: Initial experience with a novel EUS core biopsy needle demonstrates excellent pathologic diagnostic yield with a minimum number of passes.

Endoscopic placement of fully covered self-expanding metal stents (FCSEMS) to treat malignant dysphagia in patients with esophageal cancer significantly improves dysphagia; however, these stents have a high migration rate. To determine whether FCSEMS fixation using an endoscopic suturing device treated malignant dysphagia and prevented stent migration in patients with locally advanced esophageal cancer receiving neoadjuvant therapy when compared to patients with FCSEMS placement alone. A review of patients with locally advanced esophageal cancer who underwent FCSEMS placement at 3 centers was performed. Patients were divided into two groups: Group A (n = 26) was composed of patients who underwent FCSEMS placement with suture placement, and Group B (n = 67) was composed of patients with FCSEMS placement alone. There were no significant differences between Groups A and B in demographics, and tumor characteristics. The technical success rate for stent placement was 100 %. There was no difference between Groups A and B in the median stent diameter and stent lengths. Mean dysphagia score obtained at 1 week after stent placement had improved significantly from baseline (2.4 and 1, respectively, p

Background & Aims Endoscopic ultrasound–guided transmural drainage and necrosectomy have become the standard treatment for patients with pancreatic walled-off necrosis (WON). Lumen-apposing metal stents (LAMS) have shown success in the management of pancreatic fluid collections. However, there are few data on their specific roles in management of WON. We investigated the efficacy and safety of LAMS in treatment of WON. Methods We performed a retrospective multicenter case series of 124 patients with WON who underwent endoscopic transmural drainage by using LAMS at 17 tertiary care centers from January 2014 through May 2015. Patients underwent endoscopic ultrasound–guided cystogastrostomy or cystoenterostomy with placement of an LAMS into the WON collection. At the discretion of the endoscopist, we performed direct endoscopic necrosectomy, irrigation with hydrogen peroxide, and/or nasocystic drain placement. We performed endoscopic retrograde cholangiopancreatography with pancreatic duct stent placement when indicated. Concomitant therapies included direct endoscopic debridement (n = 78), pancreatic duct stent placement for leak (n = 19), hydrogen peroxide–assisted necrosectomy (n = 38), and nasocystic irrigation (n = 22). We collected data for a median time of 4 months (range, 1–34 months) after the LAMS placement. The primary outcomes were rates of technical success (successful placement of the LAMS), clinical success (resolution of WON, on the basis of image analysis, without need for further intervention via surgery or interventional radiology), and adverse events. Results The median size of the WON was 9.5 cm (range, 4–30 cm). Eight patients had 2 LAMS placed for multiport access, all with technical success (100%). Clinical success was achieved in 107 patients (86.3%) after 3 months of follow-up. Thirteen patients required a percutaneous drain, and 3 required a surgical intervention to manage their WON. The stents remained patent in 94% of patients (117 of 124) and migrated in 5.6% of patients (7 of 124). The median number of endoscopic interventions was 2 (range, 1–9 interventions). Conclusions On the basis of a retrospective analysis of 124 patients, endoscopic therapy of WON by using LAMS is safe and effective. Creation of a large and sustained cystogastrostomy or cystoenterostomy tract is effective in the drainage and treatment of WON.

En este estudio se investigó cómo los adolescentes con experiencia de embarazo evaluaron el apoyo que recibieron de su familia, en comparación con un grupo de adolescentes que no había pasado por esta experiencia. Participaron 452 adolescentes de ambos sexos, con edades entre 14 y 19 años y nivel socioeconómico bajo. Los resultados señalan que, proporcionalmente, más mujeres (64.2%) que hombres (35.8%) relataron haber tenido experiencia de embarazo, ?2 (2, n = 2617) = 48.32, p < .001. Además, se observó que el grupo con experiencia de embarazo, comparado con el grupo sin experiencia, reveló mayor percepción de seguridad en las relaciones familiares, t (408) = -3.0, p < .01; de respeto mutuo entre los miembros de la familia, t (392) = -2.3, p < .05; y que recibieron apoyo general más fuerte de su familia, t (397) = -1.3, p < .05. Estos resultados son discutidos en este texto.

[EN] In this paper we present the synthesis, characterization and catalytic behaviour in the oxidative dehydrogenation of ethane of NiO-CeO2 mixed oxides. The addition of cerium oxide to NiO strongly modifies its catalytic performance, although the changes in the catalytic behaviour depend on the catalyst composition. The incorporation of low amounts of cerium oxide to NiO multiplies the productivity to ethylene in the oxidative dehydrogenation of ethane by a factor of ca. 7, which is the result of an increase in both catalytic activity and selectivity to ethylene. The enhanced activity has been related to the remarkable increase of the surface area of catalyst and the low crystal sizes of NiO that takes place when a tiny amount of cerium oxide is incorporated to the NiO. The higher selectivity to ethylene has been related to the modification of the nature of Ni-O species, which implies a lower production of carbon oxides. On the other hand, high activity and selectivity is also observed over catalysts rich in cerium ( with Ni/ Ce ratios between 0.2 and 3). In this case, a different mechanism can be proposed in which the high capacity of CeO2 to bomb oxygen from bulk to surface and the partial formation of NiO and Ce1-xNixO2 facilitates a faster reoxidation of active Ni-sites by a synergic effect improving catalytic activity. (C) 2011 Elsevier B.V. All rights reserved., The authors would like to thank the DGICYT in Spain (Project CTQ2009-14495) for financial support. SH thanks a fellowship from DGICYT.

[EN] This work reports the applicability of reflux to the synthesis of Mo-V-Te-Nb-O metal oxide catalysts for the first time. The well-formed and defined orthorhombic M1 phase, i.e. Te2M20O57 (M = Mo, V, Nb), was found to be better developed when a longer time was used to reflux the mixed metal clusters. The catalysts efficient for propane selective oxidation to acrylic acid, reaching ca. 60% of selectivity to acrylic acid at propane conversion of ca. 50% and at a reaction temperature of 693 K. In addition, a parallel between catalytic activity and catalyst reducibility is also concluded. (C) 2011 Elsevier B.V. All rights reserved., The authors would like to thank the Malaysian government (Science Fund 03-01-04-SF0642 and research fellowship grants) and DGICYT in Spain (Project CTQ2009-14495) for their financial support.

Nocturnal reflux is a largely undiagnosed and unmanaged condition predisposing to multiple esophageal complications. We evaluated the effects of rabeprazole and pantoprazole on nocturnal intragastric pH and gastric acid output during Day 1 of therapy following the consumption of standard meals.The study had a double-blinded, randomized, two-way crossover design, and involved 15 patients with a history of mild reflux. Following an overnight fast, patients were given either rabeprazole (20 mg) or pantoprazole (40 mg) prior to the first of three standard Western meals. They then underwent overnight continuous intragastric pH monitoring and gastric acid output measurement. The drug effect was analyzed using a two-treatment, two-period crossover mixed model.The percentage of time during which the mean intragastric pH was greater than 4.0 and gastric acid output was less than 2.0 was higher for oral rabeprazole (p0.05). The inhibition of acid output was greater for rabeprazole at almost all time points. Furthermore, the mean time-matched pH values differed significantly over the first 8.3 hours (p0.05).On day 1, oral rabeprazole inhibited acid output to a greater extent and for a longer period than pantoprazole, and the intragastric pH was significantly higher for rabeprazole than for pantoprazole over the first 8.3 hours.

To improve diagnostic yield of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in solid pancreatic lesions, on-site cytology review has been recommended. Because this is not widely available throughout the world, the aim of this study was to compare the diagnostic yield of EUS-FNA performed with rapid on-site evaluation (ROSE) versus 7 FNA passes without ROSE in pancreatic masses.In this multicenter randomized noninferiority trial, patients were randomized to ROSE versus 7 passes into a solid pancreatic mass. On the basis of the absolute difference in diagnostic yield with 7 passes versus cytopathologist-guidance, the noninferiority margin for the difference in diagnostic yield was defined as -15%. Definite diagnosis was defined to include positive for malignancy, neoplastic cells present, and negative for malignancy.A total of 142 patients were randomized with 73 in the cytopathologist arm and 69 in the 7 passes arm. Diagnostic yield for definite diagnosis was 78.3% with 7 passes and 78.1% with cytopathology guidance. With an absolute difference 0.2%, 95% CI -14.4 to 14.6, performing 7 passes was noninferior to cytopathologist-guided EUS-FNA. There was no significant difference in complications or time to perform FNA. A median of 5 passes were performed with ROSE. The median charge with onsite cytopathology was significantly greater than performing 7 passes [$1058 (958, 1445) versus $375 (275, 460), p0.001].The diagnostic yield for performing 7 passes during EUS-FNA into solid pancreatic masses is noninferior with lower charge compared to cytopathologist-guidance. This article is protected by copyright. All rights reserved.

Nonalcoholic fatty liver disease (NAFLD) is a serious public health concern that affects almost one third of the US population. The prevalence of NAFLD varies among ethnic/racial groups, with the Latin American population being affected disproportionately. The severity of NAFLD also may be greater in the Latino population. The increased prevalence and severity of NAFLD in Latino Americans likely is related to the interplay between issues such as genetic factors, access to health care, or the prevalence of chronic diseases such as metabolic syndrome or diabetes. In this review, we summarize the current literature on the prevalence and risk factors of NAFLD that are seen to be more common in the Latino population in the United States. Finally, we discuss available treatment options, medical and surgical, that are available for NAFLD and how they affect the Latino population. Health care providers need to address modifiable risk factors that impact the natural history as well as treatment outcomes for NAFLD among Latinos. Additional efforts are needed to improve awareness and health care utilization for Latinos.

Background and Aims EUS-guided drainage of peripancreatic fluid collection (PFC) (pancreatic pseudocyst [PP] or walled-off necrosis [WON]) by using a novel lumen-apposing, fully covered, self-expandable metal stent (LAMS) has been promising, but few of these data are from the United States. The aim of this study was to evaluate clinical outcomes and safety of EUS-guided drainage of pancreatic pseudocysts and WON by using the LAMS. Methods We conducted a multicenter, retrospective study on 82 patients with symptomatic PFC who underwent EUS-guided drainage by using the LAMS at 4 U.S. tertiary care centers. Outcomes evaluated included successful placement of the LAMS, the number of patients in whom complete resolution of PPs or WON was achieved, the number of procedures performed per patient to achieve PFC resolution, and adverse events. Results The mean size of the PFC was 11.8 cm. LAMSs were successfully placed in 80 patients (97.5%). Twelve patients had PP and 68 had WON. The median stent in-dwelling time was 2 months (range 1-3 months). Endoscopic debridement with the LAMS in WON was performed in 54 patients. The patency of the stent was maintained in 98.7% of the patients (77/78). There was spontaneous dislodgment of 2 LAMSs. Successful endoscopic therapy by using the LAMS was successful in 12 of 12 patients (100%) with PP compared with 60 of 68 patients (88.2%) with WON. All stents were endoscopically removed from all patients after peripancreatic fluid collection (PFC) resolution. There was 1 PFC recurrence during the 3-month median follow-up period. Procedure-related adverse events occurred in 8 patients (9.8%), and included stent maldeployment (n = 2), and self-limited bleeding (n = 6). In 1 patient with stent maldeployment gastric perforation developed, and the patient underwent surgical repair. Conclusion EUS-guided drainage of PFCs by using the novel LAMS has high technical and long-term success rates. Due to its ease of use, the LAMSs may simplify and streamline EUS-guided management of PFCs, particularly for the endoscopic debridement of WON, and may help in its widespread adoption as an alternative to surgery.

V-containing materials have been proposed as active and selective catalysts in the selective oxidative transformation of C2–C4 alkanes to the corresponding olefins, oxygenates and nitriles. Although vanadium ions are generally assumed as the active sites in the oxidative activation of short chain alkanes, the coordination, the oxidation state and the environment of V atoms strongly influence both the catalytic activity and the nature of the reaction products. A comparative study on the catalytic behaviour of V-containing catalysts, i.e. metal vanadates, supported vanadium oxides, V-containing microporous/mesoporous materials and multicomponent bulk Mo–V–Te(Sb)–Nb mixed metal oxides, on the alkane oxidation is presented. The influence of the structure (including the V-coordination and V-environment) and the physico-chemical properties (especially redox and acid–base characteristics) of the catalysts on their behaviour in the selective oxidation of paraffins and alkenes is discussed.

Vanadium oxide supported on siliceous ITQ-6 catalysts have been synthesized, characterized and tested in the oxidative dehydrogenation of propane. Yields to propylene of about 15% were obtained over the best catalyst. In contrast with conventional amorphous SiO 2 the high surface area of the delaminated zeolite ITQ-6 allowed a very good dispersion of vanadium oxide on its surface leading to high productivities of propylene during the oxidative dehydrogenation of propane. Unlike MCM-41, the delaminated zeolite ITQ-6 allows the incorporation of higher vanadium loadings without collapsing its structure.

The number of patients listed for liver transplantation has outpaced the number of transplants that can be performed. This disparity between transplant candidates and the availability of donor grafts has led to an increase in mortality for patients waiting for liver transplantation. One strategy used to increase the donor pool has been the utilization of expanded donor grafts, such as those from donors with hepatitis B core antibody (anti-HBc). However, use of anti-HBc-positive grafts can potentially place the recipient at risk of de novo post-transplant hepatitis B virus (HBV) infection. The spectrum of liver disease from de novo hepatitis B ranges from mild hepatitis to graft loss. Fortunately, the risk of de novo HBV infection can be decreased with administration of oral nucleosides or nucleotides and hepatitis B immunoglobulin to the recipient. This review focuses on the epidemiology, natural history, and prophylactic strategies to reduce the risk of de novo hepatitis B in liver transplant recipients who receive anti-HBc-positive grafts.

Zollinger-Ellison syndrome is characterised by refractory peptic ulcer disease, diarrhoea and gastric acid hypersecretion associated with a gastrin-secreting tumour. The incidence is unknown, but, in the US, the frequency is 0.1-3.0 million people. Zollinger-Ellison syndrome is associated with multiple endocrine neoplasia type 1 in 25-35% of the cases. The diagnosis of Zollinger-Ellison syndrome is suggested when plasma gastrin is > 1000 pg/ml and the basal acid output is > 15 mEq/h or when associated with a pH < 2. The treatment is focused on controlling gastric acid hypersecretion and localisation of the tumour and its metastases. Proton pump inhibitors are the most effective antisecretory drugs and can be administered at high dosages. This review focuses on the role of the proton pump inhibitors in the management of gastric acid hypersecretion in Zollinger-Ellison syndrome.

Although NF-κB plays an important role in pancreatitis, mechanisms underlying its activation remain unclear. We investigated the signaling pathways mediating NF-κB activation in pancreatic acinar cells induced by high-dose cholecystokinin-8 (CCK-8), which causes pancreatitis in rodent models, and TNF-α, which contributes to inflammatory responses of pancreatitis, especially the role of PKC isoforms. We determined subcellular distribution and kinase activities of PKC isoforms and NF-κB activation in dispersed rat pancreatic acini. We applied isoform-specific, cell-permeable peptide inhibitors to assess the role of individual PKC isoforms in NF-κB activation. Both CCK-8 and TNF-α activated the novel isoforms PKC-δ and -ε and the atypical isoform PKC-ζ but not the conventional isoform PKC-α. Inhibition of the novel PKC isoforms but not the conventional or the atypical isoform resulted in the prevention of NF-κB activation induced by CCK-8 and TNF-α. NF-κB activation by CCK-8 and TNF-α required translocation but not tyrosine phosphorylation of PKC-δ. Activation of PKC-δ, PKC-ε, and NF-κB with CCK-8 involved both phosphatidylinositol-specific PLC and phosphatidylcholine (PC)-specific PLC, whereas with TNF-α they only required PC-specific PLC for activation. Results indicate that CCK-8 and TNF-α initiate NF-κB activation by different PLC pathways that converge at the novel PKCs (δ and ε) to mediate NF-κB activation in pancreatic acinar cells. These findings suggest a key role for the novel PKCs in pancreatitis.