RESUMO Objetivo: Avaliar a terapia de magneto-hipertermia em modelo de tumor de glioblastoma on-a-Chip. Métodos: As nanopartículas magnéticas recobertas com aminosilana foram utilizadas para a terapia da magneto-hipertermia, sendo avaliada a taxa de absorção específica das nanopartículas magnéticas em 300 Gauss e 305kHz. Uma pré-cultura de células C6 foi realizada e, seguidamente, foi feito o cultivo das células 3D no chip. O processo de magneto-hipertermia no chip foi realizado após administração de 20μL de nanopartículas magnéticas (10mgFe/mL), utilizando os parâmetros que geraram o valor da taxa de absorção específica. A eficácia da terapia de magneto-hipertermia foi avaliada pela viabilidade celular por meio dos corantes fluorescentes acetoximetiléster de calceína (492/513nm), para células vivas, e etídio homodímero-1 (526/619nm), para células mortas. Resultados: As nanopartículas magnéticas, quando submetidas ao campo magnético alternado (300 Gauss e 305kHz), produziram um valor médio da taxa de absorção específica de 115,4±6,0W/g. A cultura 3D das células C6 avaliada por imagem de microscopia de campo claro mostrou a proliferação e a morfologia das células antes da aplicação da terapia de magneto-hipertermia. As imagens de fluorescência mostraram diminuição da viabilidade das células cultivadas no organ-on-a-Chip em 20% e 100% após 10 e 30 minutos, respectivamente, da aplicação da terapia de magneto-hipertermia. Conclusão: O processo terapêutico da magneto-hipertermia no modelo de tumor glioblastoma on-a-chip foi eficaz para produzir lise total das células após 30 minutos de terapia.

ABSTRACT Objective: To evaluate the magnetic hyperthermia therapy in glioblastoma tumor-on-a-Chip model using a microfluidics device. Methods: The magnetic nanoparticles coated with aminosilane were used for the therapy of magnetic hyperthermia, being evaluated the specific absorption rate of the magnetic nanoparticles at 300 Gauss and 305kHz. A preculture of C6 cells was performed before the 3D cells culture on the chip. The process of magnetic hyperthermia on the Chip was performed after administration of 20μL of magnetic nanoparticles (10mgFe/mL) using the parameters that generated the specific absorption rate value. The efficacy of magnetic hyperthermia therapy was evaluated by using the cell viability test through the following fluorescence staining: calcein acetoxymethyl ester (492/513nm), for live cells, and ethidium homodimer-1 (526/619nm) for dead cells dyes. Results: Magnetic nanoparticles when submitted to the alternating magnetic field (300 Gauss and 305kHz) produced a mean value of the specific absorption rate of 115.4±6.0W/g. The 3D culture of C6 cells evaluated by light field microscopy imaging showed the proliferation and morphology of the cells prior to the application of magnetic hyperthermia therapy. Fluorescence images showed decreased viability of cultured cells in organ-on-a-Chip by 20% and 100% after 10 and 30 minutes of the magnetic hyperthermia therapy application respectively. Conclusion: The study showed that the therapeutic process of magnetic hyperthermia in the glioblastoma on-a-chip model was effective to produce the total cell lise after 30 minutes of therapy.

Abstract This paper presents a study about the fracture mechanism of a ferritic stainless steel (UNS S44400 type) during a tensile test. The applied materials for the experimental procedures were 25 specimens of the steel, machined in the rolling direction. Each specimen was submitted to standard polishing procedures. One of the samples, in the original state, was structurally characterized by reflected light optical microscopy. The other samples were submitted to tensile tests with a constant displacement rate. Three samples were tested until failure (complete tests) and the others just until specific strain values, when the tests were interrupted and the samples were characterized by using optical and scanning electron microscopy. The main objective of these characterizations was to evaluate the structural damage evolution and to identify the fracture mechanism for the tested conditions. A methodology to quantify the damage evolution by surface roughness, identified by optical microscopy, was proposed. A new index - Damage by Diffuse Reflection Index (DRI) - was proposed to quantify the damage evolution in function of the specimen deformation. It was possible to confirm the ductile behavior of the studied steel and that the main fracture mechanism was the traditional dimpled rupture.

INTRODUCTION: Cystadenoma is an uncommon epithelial neoplasia that arises from the salivary glands. The malignancy can affect structures such as the larynx, nasopharynx, buccal mucosa, and palate. OBJECTIVE: To describe a case of a giant cystadenoma of the floor of the mouth treated at a public hospital in midwestern Brazil. CASE REPORT: The patient was a 46-year-old woman with complaints of difficulties in articulating words and swallowing solid food and vocal fatigue. The progression of the disease since the initial consultation, the results of clinical examinations, and the outcome of surgery are described. FINALS COMMENTS: Cystadenoma must be considered in the differential diagnosis of cystic injuries in the floor of the mouth if the patient's symptoms are suggestive of this malignancy.

INTRODUÇÃO: O linfoma nasal primário é um tumor extranodal raro e representa 0,44% de todos os linfomas extranodais nessa localização. O linfoma nasal primário deriva da linhagem T em torno de 75% dos casos. OBJETIVO: Descrever um caso de Linfoma nasossinusal de células T Natural Killer, atendido no Hospital das Clínicas da Universidade Federal de Goiás. RELATO DO CASO: Paciente de 48 anos, sexo feminino, apresentando tumefação difusa na hemiface esquerda, de consistência firme-elástica e dolorosa a compressão digital. Tomografia dos seios da face identificou um velamento maxilar total à esquerda e de algumas células etmoidais posteriores. Com a hipótese diagnóstica de uma afecção tumoral, optou-se por remoção cirúrgica via transmaxilar, sendo encaminhado o material para biopsia. O exame histopatológico diagnosticou um tumor altamente necrótico padrão angiocêntrico, população linfoide polimórfica e atípica (Linfoma T/NK), diante do diagnóstico a paciente foi submetida à quimioterapia com regressão total do edema facial. COMENTÁRIOS FINAIS: O otorrinolaringologista deve estar atento para a existência dos linfomas entre as doenças nasossinusais, pois o diagnóstico precoce melhora a sobrevida na medida em que previne metástases, crescimento e destruição local.

INTRODUCTION: The primary nasal lymphoma is an uncommon extranodal tumor and represents 0.44% of all Extranodal lymphomas in this region. The primary nasal lymphoma derives from the T-lineage in nearly 75% of the cases. OBJECTIVE: To describe a case of nasosinusal lymphoma of T Natural Killer cells, attended in the Clinical Hospital of the Federal University of Goiás. CASE REPORT: 48-year-old female patient with diffuse tumefaction in the left hemiface of firm-elastic consistency and painful upon digital compression. Face sinuses tomography identified a total maxillary veiling to the left and some posterior ethmoidal cells. With the diagnostic hypothesis of a tumor affection, we opted for the surgical removal via a transmaxillary approach and the material was sent for biopsy. The histopathological exam diagnosed a highly necrotic tumor of angiocentric pattern, polymorphic and atypical lymphoid population (T /NK Lymphoma); with the prognosis, the patient was submitted to chemical therapy with total regression of the facial edema. FINAL COMMENTS: The otorhinolaryngologist must be attentive as regards the existence of lymphomas among the nasosinusal diseases, because the early diagnosis improves the survival as it prevents metastases, growth and local destruction.