Influence of limestone grain size on glass homogeneity

International audienceThe lack of homogeneity in a glass is characterized by the occurrence of layers of different chemical compositions and densities. When starting materials relevant for the synthesis of soda-lime silicate glasses are melted in a crucible, silica- and calcium-enrichments are observed at the top and at the bottom of the melt respectively. This behaviour may be due to the occurrence of several reaction pathways. In this respect, an interesting observation is that the grain size of limestone is found to be an important parameter influencing the level of glass homogeneity. The reasons for this have been studied here using systematic differential thermal analysis and thermogravimetric analysis. The experiments showed that, in presence of limestone of small grain size (< 200 micrometers), sodium carbonate disappears before the temperature at which it is observed to interact with silica in the CaO - free system. We infer that this is most probably due to production of a mixed carbonate liquid, which subsequently reacts with silica to spontaneously yield a homogeneous silicate melt. A characteristic of this probable mixed carbonate (assumed to be close to the composition CaNa2(CO3)2) is its density of 2.54g/cm3, close to that of the silicates and of silica itself. On the contrary, coarse limestone decomposes to CaO (and CO2), which is slowly incorporated in the sodium silicate liquid formed when sodium carbonate interacts with silica. The much higher density of CaO (3.35 g/cm3) and of calcium silicates could explain the tendency for CaO concentrations to be greatest towards the base of melting crucibles

National survey of invasive procedural training for nephrology fellows and residents in France: from bedside mentoring to simulation-based teaching

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Liver transplantation for hepatocellular carcinoma after down staging with sorafenib: a monocentric case-matched series

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The white test for intraoperative screening of bile leakage: a potential trigger factor for acute pancreatitis after liver resection—a case series

International audienceAcute pancreatitis after liver resection is a rare but serious complication, and few cases have been described in the literature. Extended lymphadenectomy, and long ischemia due to the Pringle maneuver could be responsible of post-liver resection acute pancreatitis, but the exact causes of AP after hepatectomy remain unclear. Cases presentation We report here three cases of AP after hepatectomy and we strongly hypothesize that this is due to the bile leakage white test. 502 hepatectomy were performed at our center and 3 patients (0.6%) experienced acute pancreatitis after LR and all of these three patients underwent the white test at the end of the liver resection. None underwent additionally lymphadenectomy to the liver resection. All patient had a white-test during the liver surgery. We identified distal implantation of the cystic duct in these three patients as a potential cause for acute pancreatitis. Conclusion The white test is useful for detection of bile leakage after liver resection, but we do not recommend a systematic use after LR, because severe acute pancreatitis can be lethal for the patient, especially in case of distal cystic implantation which may facilitate reflux in the main pancreatic duct

Consequences of metabolic syndrome on postoperative outcomes after pancreaticoduodenectomy

AIM To analyze immediate postoperative outcomes after pancreaticoduodenectomy regarding metabolic syndrome. METHODS In two academic centers, postoperative outcomes of patients undergoing pancreaticoduodenectomy from 2002 to 2014 were prospectively recorded. Patients presenting with metabolic syndrome [defined as at least three criteria among overweight (BMI ≥ 28 kg/m2), diabetes mellitus, arterial hypertension and dyslipidemia] were compared to patients without metabolic syndrome. RESULTS Among 270 consecutive patients, 29 (11%) presented with metabolic syndrome. In univariable analysis, patients with metabolic syndrome were significantly older (69.4 years vs 62.5 years, p = 0.003) and presented more frequently with soft pancreas (72% vs 22%, p = 0.0001). In-hospital morbidity (83% vs 71%) and mortality (7% vs 6%) did not differ in the two groups so as pancreatic fistula rate (45% vs 30%, p = 0.079) and severity of pancreatic fistula (p = 0.257). In multivariable analysis, soft pancreas texture (p = 0.001), pancreatic duct diameter 30 kg/m2 (p = 0.041) were identified as independent risk factors of pancreatic fistula after pancreaticoduodenectomy, but not metabolic syndrome. CONCLUSION In spite of logical reasoning and appropriate methodology, present series suggests that metabolic syndrome does not jeopardize postoperative outcomes after pancreaticoduodenectomy. Therefore, definition of metabolic syndrome seems to be inappropriate and fatty pancreas needs to be assessed with an international consensual histopathological classification

Comparison of different feeding regimes after pancreatoduodenectomy - a retrospective cohort analysis

Abstract Background Delayed gastric emptying (DGE) is the most frequent pancreatic specific complication (PSC) after pancreaticoduodenectomy (PD). Several gastric decompression systems exist to manage DGE. Patients with a pancreatic tumor require prolonged nutrition; however, controversies exist concerning nutrition protocol after PD. The aim of the study was to assess the safety and efficacy of nasogastric (NG), gastrostomy (GT), and gastrojejunostomy (GJ) tubes with different feeding systems on postoperative courses. Methods Between January 2013 and March 2016, 86 patients underwent PD with pancreaticogastrostomy. Patients were divided into three groups: GJ group with enteral nutrition (EN, n = 12, 14%), NG (n = 31, 36%) and GT groups (n = 43, 50%), both with total parenteral nutrition (TPN). Results Patients in the GJ (n = 9, 75%) and GT (n = 18, 42%) groups had an American Society of Anesthesiologists (ASA) score of 3 more often than those in the NG group (n = 5, 16%, p ≤ 0.01). Multivariate analysis identified the GT tube with TPN as an independent risk factor of severe morbidity (p = 0.02) and DGE (p < 0.01). An ASA score of 3, jaundice, common pancreatic duct size ≤3 mm and soft pancreatic gland texture (p < 0.05) were found as independent risk factors of PSCs. Use of a GJ tube with EN, GT tube with TPN, jaundice, and PSCs were identified as independent risk factors for greater postoperative length of hospital stay (p < 0.01). Mean global hospitalization cost did not differ between groups. Conclusion GT tube insertion with TPN was associated with increased severe postoperative morbidity and DGE and should not be recommended. EN through a GJ tube after PD is feasible but does not have clear advantages on postoperative courses compared to an NG tube

Cognitive impairment was associated with brain-blood barrier permeability in two models of chronic kidney disease in rats

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Peri-operative risk factors of chronic kidney disease after liver transplantation

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