Films of TiO2 were deposited over glass substrates using sedimentation under acidity conditions in order to evaluate in laboratory conditions the COD, colour and faecal coliforms removal in pre-treated leaching for anaerobic digestion. In agreement with the ANOVA results of factorial design 2², the interaction of X1 (Number of cycles of growth associated with sedimentations) and X2 (Steeping time of the TiO2) did not have a significant effect on the glass adhered milligrams of TiO2 (p = 0,138). Nevertheless, X1 factor in its high level (Two cycles made up of: 2 sedimentations of 1 h and 2 calcinations of 1 h to 450 °C) results in a significant effect (p < 0.0001) adhering 7.42 mg/cm² of TiO2 on the glass substrate . The films displayed a rough, irregular surface and presented small fractures. The X-ray diffractograms of these were TiO2 films showed the presence of the phases rutile (110), (101) and anatase (101), (200), (211) and (004), which intensified after the heat treatment. In the photocatalytic curves the results were 26 %, 40 % and 60 % the colour, COD and faecal coliforms removal respect at 12 h.

Se elaboraron películas de TiO2 sobre vidrio empleando sedimentación bajo condiciones de acidez para evaluarlas a escala de laboratorio en la remoción de DQO, color y coliformes fecales presentes en un lixiviado pre-tratado por digestión anaeróbica. De acuerdo con los resultados de la prueba ANOVA para el diseño factorial 2², la interacción de X1 (Número de ciclos de crecimiento asociados con sedimentación) y X2 (Tiempo de reposo del TiO2) no tuvo un efecto significativo sobre los miligramos de TiO2 adheridos (p = 0.138). Sin embargo, el factor X1 en su nivel alto (Dos ciclos compuestos por: 2 etapas de sedimentación de 1 h y 2 calcinaciones de 1 h a 450 °C) sí tuvo un efecto significativo (p < 0.0001) adhiriéndose 7.42 mg/cm² de TiO2. Las películas presentaron una superficie rugosa, granular y con pequeñas fracturas. Con respecto al patrón de difracción de las películas de TiO2 se observaron las fases rutilo (110), (101) y anatasa (101), (200), (211) y (004), las cuales se intensificaron después del tratamiento térmico. En las curvas de remoción se obtuvo 26 %, 40 % y 60 % de decoloración, remoción de DQO e inactivación de coliformes fecales respectivamente a las 12 h.

Staphylococcus aureus is a pathogen that has been associated with nosocomial infections since the preantibiotic era. Since the introduction of antibiotics in medical practice in the 1940 s, methicillin-resistant S. aureus (MRSA) strains have been emerging in various parts of the world. In view of the important role of the phagocytic system in the defense against this bacteria, we decided to study phagocytosis by neutrophils and monocytes of an epidemic MRSA strain in São Paulo, Brazil, in comparison with methicillin-sensitive strains. Complement system opsonins are fundamental for efficient ingestion of the resistant and sensitive strains by both types of phagocytes. We found no association of the opsonic requirement of the MRSA strain with the multiresistance phenotype. On the other hand, the MRSA strain was found to be more resistant to the effector mechanisms of neutrophils than both sensitive strains when opsonized with fresh serum, despite the phagocytosis results. This fact suggests that the intracellular killing of S. aureus is an additional parameter of bacterial virulence, but new approaches must be implemented to study the interactions of this MRSA strain with phagocytes in order to investigate the possible factors involved in its behavior in response to neutrophil effector mechanisms.