RESUMO
In this work, our goal was to study the capability of a single metallic oxide to neutralize a chemical agent and to exhibit an antibacterial effect. We tested two types of magnesium oxides, MgO. The first MgO sample tested, which commercial data size characteristic was -325 mesh (MgO-1) destroyed in 3 h, 89.7% of paraoxon and 93.2% of 4-nitrophenol, the first degradation product. The second MgO sample, which commercial data size was <50 nm (MgO-2) neutralized in the same time, 19.5% of paraoxon and 10.9% of 4-nitrophenol. For MgO-1 no degradation products could be detected by GC-MS. MgO-1 had a bactericidal activity on Escherichia coli (6 log in 1 h), and showed a decrease of almost 3 log on a Staphylococcus aureus population in 3 h. MgO-2 caused a decrease of 2 log of a E.coli culture but had no activity against S. aureus. Neither of these two products had an activity on Bacillus subtilis spores. Analytical investigations showed that the real sizes of MgO nanoparticles were 11 nm for MgO-1 and 25 nm for MgO-2. Moreover, their crystalline structures were different. These results highlighted the importance of the size of the nanoparticles and their microscopic arrangements to detoxify chemical products and to inhibit or kill microbial strains.
Assuntos
Óxido de Magnésio/química , Nanopartículas Metálicas/química , Compostos Organotiofosforados/química , Paraoxon/química , Bacillus subtilis/fisiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Óxido de Magnésio/análise , Nanopartículas Metálicas/toxicidade , Nitrofenóis/química , Tamanho da Partícula , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Severe obesity is a common consequence of hypothalamic region diseases and their treatment. Only two previous case reports have described hypothalamic lipomas in children with obesity. We described a case of an adult with severe obesity associated with hypothalamic lipoma attached to the third ventricle floor who underwent Roux-en-Y gastric bypass. He lost 38 and 59 kg at 6 and 12 months after surgery, respectively. Weight loss after bariatric surgery was as expected in this patient with severe obesity. At 6 and 12 months, brain magnetic resonance imaging (MRI) showed stability in lipoma's size.