Search

A novel and versatile plasma reactor was used to modify Polyethersulphone commercial membranes. The equipment was applied to: i) functionalize the membranes with low-temperature plasmas, ii) deposit a film of poly(methyl methacrylate) (PMMA) by Plasma Enhanced Chemical Vapor Deposition (PECVD) and, iii) deposit silver nanoparticles (SNP) by Gas Flow Sputtering. Each modification process was performed in the same reactor consecutively, without exposure of the membranes to atmospheric air. Scanning electron microscopy and transmission electron microscopy were used to characterize the particles and modified membranes. SNP are evenly distributed on the membrane surface. Particle fixation and transport inside membranes were assessed before- and after-washing assays by X-ray photoelectron spectroscopy depth profiling analysis. PMMA addition improved SNP fixation. Plasma-treated membranes showed higher hydrophilicity. Anti-biofouling activity was successfully achieved against Gram-positive ( Enterococcus faecalis ) and -negative ( Salmonella Typhimurium) bacteria. Therefore, disinfection by ultrafiltration showed substantial resistance to biofouling. The post-synthesis functionalization process developed provides a more efficient fabrication route for anti-biofouling and anti-bacterial membranes used in the water treatment field. To the best of our knowledge, this is the first report of a gas phase condensation process combined with a PECVD procedure in order to deposit SNP on commercial membranes to inhibit biofouling formation.

Primary intraosseous salivary gland tumors of the mandible are rare, with mucopidermoid carcinoma being the most frequent, followed by adenoid cystic carcinoma (ACC). We present a case of a central ACC involving the mandible of a 46-year-old man. He presented an indurated swelling on the vestibular aspect of the left mandibular body and ipsilateral paraesthesia of the lower lip. A panoramic radiography revealed a large radiolucent area, with irregular margins, involving the body and ramus of the left mandible, and CT scan confirmed that the lesion was confined within the mandibular bone. The histopathological features were of an ACC. CT scan also revealed multiple nodular lesions in both lungs suggestive of metastases. The patient was surgically treated by hemi-mandibulectomy. The patient is well with no evidences of recurrences in the mandible. The present case shows that the clinical and immunohistochemical profile of primary intraosseous ACC is similar to what is found in ACC involving the salivary glands.