Thermal Degradation Kinetics of ZnO/polyester Nanocomposites.

ZnO particles were synthetized by the sol-gel method and subsequent heat treatment of 400, 500 and 600 °C was applied. The nano ZnO particles were incorporated to the unsaturated polyester resin by solution blending at 0.05 wt % concentration. X-ray diffraction detected the formation of a wurtzite-like structure. Viscoelastic behavior of neat polyester and nanocomposites revealed the nano ZnO particles does not promote better mechanical properties because of a weak interaction and the glass transition temperature of the polyester was favored by the presence of a higher quantity of nano-size ZnO particles. Thermogravimetric analysis at 5, 10 and 20 °C/min allowed determining the degradation kinetic parameters based on the Friedman and Kissinger models for neat polyester and nanocomposites. Heating rates promoted an increase in the temperature degradation and the addition of ZnO particles promoted a catalyst effect that reduce the amount of thermal energy needed to start the thermal degradation.

[Thromboembolic complications in inflammatory bowel disease]. / Complicaciones tromboembólicas en la enfermedad inflamatoria intestinal.

Thromboembolic complications during the course of inflammatory bowel disease are infrequent but are mainly found in young patients and are associated with a high morbimortality. The etiopathogenesis of these complications has been widely debated and the existence of coagulation alterations and fibrinolysis have been suggested. Nonetheless, the mechanism must be complex since not only do not all the patients with these alterations present this complication but neither do all the patients with thromboembolism have recognized coagulation disorders. The most common clinical presentation is deep vein thrombosis with pulmonary embolism with arterial thrombosis being rare. Five patients with Crohn's disease and two with ulcerative colitis who presented a total of new thromboembolic episodes, six arterial (1 in primitive iliac artery, 1 in common femoral artery, 1 in humeral-axillary artery, 2 in internal carotid and 1 in superior mesenteric artery) and three of venous localization (1 in brachyocephalic-subclavian trunk, 1 axillary and 1 iliac-femoral/pulmonary thromboembolism) are reported. An updated review of the etiopathogenesis, presentation, treatment and prophylaxis of the thromboembolic complications of inflammatory bowel disease is presented.

[Purtscher's retinopathy and acute alcoholic pancreatitis]. / Retinopatía de Purtscher y pancreatitis aguda alcohólica.

We report the case of a 27-year-old man with alcoholic acute pancreatitis, who developed an acute loss of visual acuity; a bilateral Purtscher's retinopathy, a rare complication of acute pancreatitis, was confirmed by ophthalmoscopy.

[Caroli's syndrome: a variable entity]. / Síndrome de Caroli: una entidad variable.

We present the case of a 56 year old woman with Caroli's disease associated to congenital liver fibrosis, renal nephrocalcinosis and cutaneous vasculitis of the legs. Clinical signs of portal hypertension were treated by a shunt technique. After an asymptomatic period, the patient suffers now from crisis of angiocholitis.

Fish allergy: evaluation of the importance of cross-reactivity.

Fish constitute one of the most important groups of allergens in the induction of immediate (type I) food hypersensitivity. In our environment, fish allergy is present in 22% of all patients with a diagnosis of food hypersensitivity. We studied the allergenic significance of the fish species considered most representative because of their greater consumption in our environment (flatfishes: Pleuronectiformes such as sole, whiff, and witch; Gadiformes such as hake; and Scombriformes such as albacore) or because of the results of previous studies of Gadiformes such as cod. Through the use of isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting, we have observed that several allergens common to all these species are able to bind specific IgE from the sera of sensitized patients. This allergenic community has been confirmed by radioallergosorbent inhibition. Another group of species-specific allergens focuses in the regions at about pH 5 and with molecular weights less than 14 kilodaltons; these allergens correspond to sarcoplasmic parvoalbumins. From the results observed, which have been confirmed by various procedures and techniques, we conclude that hake is the fish with the capability to induce the strongest IgE response, followed by whiff; the witch seems to be the least allergenic of all flatfishes. Among all species studied, albacore was the least allergenic. These results may be considered when one introduces supplementary feeding with fish in infants, most particularly in infants at high risk for atopy.