Synthesis and characterization of Poly(urea-formaldehyde) microcapsules with 5-ethylidene-2-norbornene as self-healing agent and potential use in polymeric composites.

This study describes a methodology to prepare and characterize PUF [poly(urea formaldehyde)] microcapsules containing 5-ethylidene-2-norbornene (ENB) as self-healing agent, as well as the compatibility evaluation of ENB in the presence of Grubb's catalyst with an epoxy matrix. First, the results of an adhesion assay by lap shear proved chemical compatibility between the epoxy matrix and self-healing agent in the presence of Grubb's catalyst. After evaluating the chemical compatibility, microcapsules with ENB were synthesized in an oil-in-water emulsion system. Thereafter, the microcapsules were morphologically, chemically and thermally characterized in which a granulometric dispersion between 30-140 µm and an average size of 69.8 ± 4.9 µm were observed. The SEM (scanning electron microscope) results showed that the average thickness of microcapsules shell was 3.6 ± 0.4 µm. The thermogravimetric analysis (TGA) showed that microcapsules are susceptible to rupture and consequent ENB release in temperatures greater than 230 °C, demonstrating that microcapsules are suitable for applications in materials with self-healing capacity.

The spectrum of rare central nervous system (CNS) tumors with EWSR1-non-ETS fusions: experience from three pediatric institutions with review of the literature.

The group of CNS mesenchymal (non-meningothelial) and primary glial/neuronal tumors in association with EWSR1-non-ETS rearrangements comprises a growing spectrum of entities, mostly reported in isolation with incomplete molecular profiling. Archival files from three pediatric institutions were queried for unusual cases of pediatric (≤21 years) CNS EWSR1-rearranged tumors confirmed by at least one molecular technique. Extra-axial tumors and cases with a diagnosis of Ewing sarcoma (EWSR1-ETS family fusions) were excluded. Additional studies, including anchored multiplex-PCR with next-generation sequencing and DNA methylation profiling, were performed as needed to determine fusion partner status and brain tumor methylation class, respectively. Five cases (median 17 years) were identified (M:F of 3:2). Location was parenchymal (n = 3) and undetermined (n = 2) with topographic distributions including posterior fossa (n = 1), frontal (n = 1), temporal (n = 1), parietal (n = 1) and occipital (n = 1) lobes. Final designation with fusion findings included desmoplastic small round cell tumor (EWSR1-WT1; n = 1) and tumors of uncertain histogenesis (EWSR1-CREM, n = 1; EWSR1-CREB1, n = 1; EWSR1-PLAGL1, n = 1; and EWSR1-PATZ1, n = 1). Tumors showed a wide spectrum of morphology and biologic behavior. For EWSR1-CREM, EWSR1-PLAGL1 and EWSR1-PATZ1 tumors, no significant methylation scores were reached in the known brain tumor classes. Available outcome (4/5) was reported as favorable (n = 2) and unfavorable (n = 2) with a median follow-up of 30 months. In conclusion, we describe five primary EWSR1-non-ETS fused CNS tumors exhibiting morphologic and biologic heterogeneity and we highlight the clinical importance of determining specific fusion partners to improve diagnostic accuracy, treatment and monitoring. Larger prospective clinicopathological and molecular studies are needed to determine the prognostic implications of histotypes, anatomical location, fusion partners, breakpoints and methylation profiles in patients with these rare tumors.

Reabilitação estética com pilar de zircônia / Esthetic rehabilitation in zirconia abutment

Restaurações implanto-suportadas em zonas estéticas anteriores apresentam significantes desafios tanto na fase cirúrgica como na fase protética. O aumento dos valores estéticos pela sociedade moderna tem refletido na odontologia, onde pacientes procuram por soluções não somente funcionais, mas também com excelência em estética, o que se transforma num desafio cada vez maior. Uma harmoniosa transição entre a restauração e os tecidos periimplantares é extremamente importante. A aparência de saúde gengival consiste numa coloração natural como também num apropriado contorno gengival. Em relação ao contorno gengival, os pilares de titânio vêm atingindo bons resultados, quando a qualidade e quantidade de gengiva inserida estão presentes. Porém, à medida que estas sejam diminuídas, os resultados estéticos utilizando os pilares metálicos ficam mais distantes. Alguns recursos utilizados nestas condições objetivando a estética é o pilar de Zircônia, da Empresa Conexão Sistemas de Próteses e implantes LTDA. Este pilar une resistência e estética, além de biocompatibilidade com os tecidos periimplantes. Outra vantagem é possibilitar aplicação direta da porcelana quando a indicação recair em uma prótese parafusada. Dentes naturais são geralmente translúcidos, refletem a luz incidente sobre eles, bem como a absorvem e a transmitem completamente. O objetivo do presente trabalho é demonstrar a combinação de pilares e coroas em Zircônia, permitindo a manutenção destas mesmas características, sendo mais uma opção para obtermos excelência em estética em implantodontia

Restorations in previus aesthetic zones represent a significant challenge in the surgical phase in the prosthetic phase when it is about dental implants. The increase of aesthetic values in modern society has reflected also in dentistry, where patients look for solutions not just functional. In fact, patients nowadays are very concerned about excellency in aesthetic, what increased the challenge over and over. A harmonious transition between the restoration and perioimplant tissues is extremely important. The healthy appearance of gum consist of natural coloration and also an appropriate gum contour. In relation to this contour, titanium abutments do not cause any significant problem, however, comparing the natural gum colour, this same abutments make thin periimplant tissues look slightly grey or blue. Following line of aesthetic abutments in the market, a Conexão Sistemas de Próteses e Implantes LTDA, releases their Zircônia abutments, with several advantages, for instance, being significantly stronger than other ceramics, wich results in a decrease of complications in post-treatment. This article’s objective is to show a clinical case using new zirconia abutments, which provided a “state of art” degree of aesthetic and periimplants tissues health as well