Star-Branched Polyamides as the Matrix in Thermoplastic Composites.

The aim of this study is the preparation of star-shaped branched polyamides (sPA6) with low melt viscosity, but also with improved mechanical properties by reactive extrusion. This configuration has been obtained by grafting a tri-functional, three-armed molecule: 5-aminoisophthalic-acid, used as a linking agent (LA). The balance between the fluidity, polarity and mechanical properties of sPA6s is the reason why these materials have been investigated for the impregnation of fabrics in the manufacture of thermoplastic composites. For these impregnation processes, the low viscosity of the melt has allowed the processing parameters (temperature, pressure and time) to be reduced, and its new microstructure has allowed the mechanical properties of virgin thermoplastic resins to be maintained. A significant improvement in the ultrasonic welding processes of the composites was also found when an energy director based on these materials was applied at the interface. In this work, an exhaustive microstructural characterization of the obtained sPAs is presented and related to the final properties of the composites obtained by film stacking.

Setting Relationships between Structure and Devulcanization of Ground Tire Rubber and Their Effect on Self-Healing Elastomers.

The use of devulcanized tire powder as an effective reinforcement in self-healing styrene-butadiene rubber (SBR) compounds has been investigated for the first time in this work. For this purpose, the evolution of the microstructure of the rubber from end-of-life tires (ELTs) was studied during granulation, grinding and devulcanization through an exhaustive characterization work in order to relate the final microstructure with the mechanical response of the repaired systems. Different morphologies (particle size distribution and specific surface area) obtained by cryogenic and water jet grinding processes, as well as different devulcanization techniques (thermo-mechanical, microwave, and thermo-chemical), were analyzed. The results demonstrated the key influence of the morphology of the ground tire rubber (GTR) on the obtained devulcanized products (dGTR). The predictions of the Horikx curves regarding the selectivity of the applied devulcanization processes were validated, thereby; a model of the microstructure of these materials was defined. This model made it possible to relate the morphology of GTR and dGTR with their activity as reinforcement in self-healing formulations. In this sense, higher specific surface area and percentage of free surface polymeric chains resulted in better mechanical performance and more effective healing. Such a strategy enabled an overall healing efficiency of more than 80% in terms of a real mechanical recovery (tensile strength and elongation at break), when adding 30 phr of dGTR. These results open a great opportunity to find the desired balance between the mechanical properties before and after self-repair, thus providing a high technological valorization to waste tires.

Black tongue associated with linezolid.

Darkening of the tongue and oral mucosa is a reaction pattern that can be related to a number of physiologic, metabolic, and toxic disorders, and medications and exogenous substances. Black discoloration of the tongue should be distinguished from black "hairy" tongue, which is characterized by hypertrophy of the filiform papillae. We report a case of a 42-year-old man presented with a black discoloration of his tongue during treatment with linezolid for spondylodiscitis. So in conclusion, tongue discoloration is a benign and reversible condition and a probable adverse event associated with linezolid. We present this case to increase clinicians' awareness of a new potential adverse effect of linezolid.

[Multiple inflammatory liver pseudotumors and Enterococcus durans bacteremia]. / Seudotumor inflamatorio hepático múltiple y bacteriemia por Enterococcus durans.

Inflammatory pseudotumors are rare benign lesions that can occur throughout the body. These masses are usually associated with fever, pain, and mass effect, and are frequently mistaken for malignant neoplasms. Liver pseudotumors are especially rare, with 150 cases reported up to 2007, since the original report of Pack and Baker in 1953. We describe the case of a patient with suspected multiple hepatic abscesses, who was finally diagnosed with an inflammatory pseudotumor by percutaneous biopsy. The patient received prolonged antibiotic therapy, with complete resolution of the pseudotumor. The differential diagnosis and management of this entity is discussed.

Seudotumor inflamatorio hepático múltiple y bacteriemia por Enterococcus durans / Multiple inflammatory liver pseudotumors and Enterococcus durans bacteremia

Los seudotumores inflamatorios son lesiones raras, benignas y con diferentes localizaciones. Habitualmente asocian fiebre, dolor y efecto masa, y con frecuencia pueden diagnosticarse erróneamente como neoplasias. Los seudotumores hepáticos son especialmente infrecuentes, con menos de 150 casos descritos hasta 2007 tras la primera descripción de Pack y Baker en 1953. Describimos el caso de un paciente con sospecha de abscesos hepáticos múltiples, diagnosticado finalmente de seudotumor inflamatorio hepático mediante biopsia de la lesión. Recibió tratamiento antibiótico prolongado hasta la resolución del cuadro. Se discutirá el manejo clínico y el diagnóstico diferencial(AU)

Inflammatory pseudotumors are rare benign lesions that can occur throughout the body. These masses are usually associated with fever, pain, and mass effect, and are frequently mistaken for malignant neoplasms. Liver pseudotumors are especially rare, with 150 cases reported up to 2007, since the original report of Pack and Baker in 1953. We describe the case of a patient with suspected multiple hepatic abscesses, who was finally diagnosed with an inflammatory pseudotumor by percutaneous biopsy. The patient received prolonged antibiotic therapy, with complete resolution of the pseudotumor. The differential diagnosis and management of this entity is discussed(AU)

Probable caso de anaplasmosis humana importada / Probable case of imported human anaplasmosis

No disponible

Meningitis por Bacteroides fragilis en pacientes con infección por el VIH / Bacteroides fragilis meningitis in HIV patient

No disponible