Interplay of internal stresses, electric stresses and surface diffusion in polymer films

We investigate two destabilization mechanisms for elastic polymer films and put them into a general framework: first, instabilities due to in-plane stress and second due to an externally applied electric field normal to the film's free surface. As shown recently, polymer films are often stressed due to out-of-equilibrium fabrication processes as e.g. spin coating. Via an Asaro-Tiller-Grinfeld mechanism as known from solids, the system can decrease its energy by undulating its surface by surface diffusion of polymers and thereby relaxing stresses. On the other hand, application of an electric field is widely used experimentally to structure thin films: when the electric Maxwell surface stress overcomes surface tension and elastic restoring forces, the system undulates with a wavelength determined by the film thickness. We develop a theory taking into account both mechanisms simultaneously and discuss their interplay and the effects of the boundary conditions both at the substrate and the free surface.Comment: 14 pages, 7 figures, 1 tabl

Criptococosis felina : un caso clínico

Un gato común macho de 10 años de edad, se presentó con una historia crónica de vómitos, diarreas, anorexia y abatimiento. Posteriormente se desarrolló un cuadro neurológico, ocular y renal. El estudio de la citología permitió el diagnóstico de una criptococosis diseminada.A ten year old domestic male cat was presented with a chronic history of vomiting, diarrhea, anorexia and depression. Neurological, ocular and renal signs subsequently developed. A diagnosis of systemic cryptococosis was made by citology

Citizenship:Contrasting Dynamics at the Interface of Integration and Constitutionalism

EUDO Citizenship ObservatoryThis paper explores the different ways in which citizenship has played a role in polity formation in the context of the European Union. It focuses on both the ‘integration’ and the ‘constitution’ dimensions. The paper thus has two substantive sections. The first addresses the role of citizenship of the Union, examining the dynamic relationship between this concept, the role of the Court of Justice, and the free movement dynamic of EU law. The second turns to citizenship in the Union, looking at some recent political developments under which concepts of citizenship, and democratic membership as a key dimension of citizenship, have been given greater prominence. One key finding of the paper is that there is a tension between citizenship of the Union, as part of the EU's ‘old’ incremental constitutionalism based on the constitutionalisation of the existing Treaties, and citizenship in the Union, where the possibilities of a ‘new’ constitutionalism based on renewed constitutional documents have yet to be fully realise

Archivo sobre cardiopatías congénitas. Grupo GECAR-AVEPA

En este artículo se presentan los objetivos y las pautas para la elaboración de un archivo sobre cardiopatías congénitas en pequeños animales a nivel nacional, elaborados por una comisión de miembros del Grupo de Especialistas en Cardiorrespiratorio (GECAR) de AVEPA.

Plasmocitoma intratraqueal en un perro : diagnóstico y tratamiento

Un perro macho entero de 12 años, se presentó en la consulta con cuadro clínico cíclico de aumento de los sonidos respiratorios de 2-3 meses de duración. Estas crisis se presentaban siempre con el animal en reposo, nunca durante el ejercicio. En la exploración física no se detectaron ni tos ni anormalidades anatómicas en la palpación de la región cervical. Radiografías de la zona cérvico-torácica revelaron una estructura con densidad de tejido blando en la luz traqueal, a la altura del espacio intervertebral C5-C6. Se confirmó, mediante examen broncoscópico, la presencia de una masa pediculada que se extendía en el lumen traqueal y ocupaba aproximadamente el 90% de su diámetro, aunque permitía el paso del broncoscopio hasta la carina. Esta masa fue extirpada quirúrgicamente sin complicaciones. Los resultados del examen anatomopatológico resultaron diagnósticos de plasmocitoma, y seis meses tras la resección quirúrgica no ha habido recidiva de los signos clínicos

Mobilization of xanthine oxidase from the gastrointestinal tract in acute pancreatitis

BACKGROUND: Xanthine oxidoreductase has been proposed to play a role in the development of local and systemic effects of acute pancreatitis. Under physiologic conditions, the enzyme exists mainly as xanthine dehydrogenase (XDH) but can be converted by proteolytic cleavage to its superoxide-generating form xanthine oxidase (XOD). In addition to its intracellular location XDH/XOD is also associated to the polysaccharide chains of proteoglycans on the external endothelial cell membrane. In the early stages of acute pancreatitis, this enzyme seems to be arising from its mobilization from the gastrointestinal endothelial cell surface. Taking into account the ability of α-amylase to hydrolyze the internal α-1,4 linkages of polysaccharides, we wanted to elucidate the involvement of α-amylase in XDH/XOD mobilization from the gastrointestinal endothelial cell surface and the relevance of the ascitic fluid (AF) as the source of α-amylase in experimental acute pancreatitis. METHODS: Acute pancreatitis was induced in male Wistar rats by intraductal administration of 5% sodium taurocholate. In another experimental group 3000 U/Kg α-amylase was i.v. administered. The concentrations of XDH, XOD and α-amylase in plasma and AF and myeloperoxidase (MPO) in lung have been evaluated. In additional experiments, the effect of peritoneal lavage and the absorption of α-amylase present in the AF by an isolated intestine have been determined. RESULTS: Similar increase in XDH+XOD activity in plasma was observed after induction of acute pancreatitis and after i.v. administration of α-amylase. Nevertheless, the conversion from XDH to XOD was only observed in the pancreatitis group. Lung inflammation measured as MPO activity was observed only in the pancreatitis group. In addition peritoneal lavage prevented the increase in α-amylase and XDH+XOD in plasma after induction of pancreatitis. Finally, it was observed that α-amylase is absorbed from the AF by the intestine. CONCLUSIONS: During the early stages of acute pancreatitis, α-amylase absorbed from AF through the gastrointestinal tract could interfere with the binding of XDH/XOD attached to glycoproteins of the endothelial cells. Proteolytic enzymes convert XDH into its oxidase form promoting an increase in circulating XOD that has been reported to be one of the mechanisms involved in the triggering of the systemic inflammatory process

Dietary Fat Patterns and Outcomes in Acute Pancreatitis in Spain

Background/Objective: Evidence from basic and clinical studies suggests that unsaturated fatty acids (UFAs) might be relevant mediators of the development of complications in acute pancreatitis (AP). Objective: The aim of this study was to analyze outcomes in patients with AP from regions in Spain with different patterns of dietary fat intake. Materials and Methods: A retrospective analysis was performed with data from 1,655 patients with AP from a Spanish prospective cohort study and regional nutritional data from a Spanish cross-sectional study. Nutritional data considered in the study concern the total lipid consumption, detailing total saturated fatty acids, UFAs and monounsaturated fatty acids (MUFAs) consumption derived from regional data and not from the patient prospective cohort. Two multivariable analysis models were used: (1) a model with the Charlson comorbidity index, sex, alcoholic etiology, and recurrent AP; (2) a model that included these variables plus obesity. Results: In multivariable analysis, patients from regions with high UFA intake had a significantly increased frequency of local complications, persistent organ failure (POF), mortality, and moderate-to-severe disease in the model without obesity and a higher frequency of POF in the model with obesity. Patients from regions with high MUFA intake had significantly more local complications and moderate-to-severe disease; this significance remained for moderate-to-severe disease when obesity was added to the model. Conclusions: Differences in dietary fat patterns could be associated with different outcomes in AP, and dietary fat patterns may be a pre-morbid factor that determines the severity of AP. UFAs, and particulary MUFAs, may influence the pathogenesis of the severity of AP

Validation of bioelectrical impedance analysis for body composition assessment in children with obesity aged 8-14y

BACKGROUND & AIMS: The aim was to generate a predictive equation to assess body composition (BC) in children with obesity using bioimpedance (BIA), and avoid bias produced by different density levels of fat free mass (FFM) in this population. METHODS: This was a cross-sectional validation study using baseline data from a randomized intervention trial to treat childhood obesity. Participants were 8 to 14y (n = 315), underwent assessments on anthropometry and BC through Air Displacement Plethysmography (ADP), Dual X-Ray Absorptiometry and BIA. They were divided into a training (n = 249) and a testing subset (n = 66). In addition, the testing subset underwent a total body water assessment using deuterium dilution, and thus obtained results for the 4-compartment model (4C). A new equation to estimate FFM was created from the BIA outputs by comparison to a validated model of ADP adjusted by FFM density in the training subset. The equation was validated against 4C in the testing subset. As reference, the outputs from the BIA device were also compared to 4C. RESULTS: The predictive equation reduced the bias from the BIA outputs from 14.1% (95%CI: 12.7, 15.4) to 4.6% (95%CI: 3.8, 5.4) for FFM and from 18.4% (95%CI: 16.9, 19.9) to 6.4% (95% CI: 5.3, 7.4) for FM. Bland-Altman plots revealed that the new equation significantly improved the agreement with 4C; furthermore, the observed trend to increase the degree of bias with increasing FM and FFM also disappeared. CONCLUSION: The new predictive equation increases the precision of BC assessment using BIA in children with obesity