Keratin peptides from chicken feathers for biomedical applications

Book of Abstracts of CEB Annual Meeting 2017info:eu-repo/semantics/publishedVersio

Estudo das propriedades morfológicas, térmicas e mecânicas do compósito particulado de alumínio e polietileno de baixa densidade reciclados

Frente à crescente necessidade de recuperar o meio ambiente e seus recursos naturais, atualmente a recicla-gem e reutilização dos materiais torna-se uma das soluções sustentáveis mais visadas. Neste cenário, o pro-cessamento de compósitos particulados de alumínio em matriz termoplástica de polietileno de baixa densida-de (PEBD), provenientes da reciclagem de embalagens longa vida, apresenta-se de maneira atrativa para a obtenção de matéria prima para a construção civil, na fabricação de telhas de baixo peso, associado a baixo custo e elevada disponibilidade, dentre outras aplicações. Este trabalho tem por objetivo estudar as proprie-dades e o comportamento do compósito de polietileno de baixa densidade/alumínio reciclados. Com este ob-jetivo, foi realizada a avaliação morfológica do compósito a partir de microscopia óptica (MO), microscopia eletrônica de varredura (MEV) e espectroscopia por energia dispersiva de raios X (EDS), bem como avalia-dos os comportamentos térmico e mecânico deste material após estes terem sido submetidos à climatização higrotérmica e por radiação ultravioleta (UV). Para a avaliação térmica foram empregadas técnicas de análise termogravimétrica (TGA) e calorimetria exploratória diferencial (DSC). As propriedades mecânicas foram avaliadas por análise dinâmico-mecânica (DMA) e ensaios de tração e impacto. A partir dos resultados obti-dos por meio deste trabalho pode-se concluir que o intemperismo envolvendo umidade e radiação UV pode influenciar nos desempenhos térmico e mecânico do compósito de Alumínio/PEBD, porém, foi observado que esta influência não é suficiente para inviabilizar a utilização destes materiais na construção civil, garan-tindo este mercado para o compósito de PEBD/Al

BIM Mediates EGFR Tyrosine Kinase Inhibitor-Induced Apoptosis in Lung Cancers with Oncogenic EGFR Mutations

Background: Epidermal growth factor receptor (EGFR) mutations are present in the majority of patients with non-small cell lung cancer (NSCLC) responsive to the EGFR tyrosine kinase inhibitors (TKIs) gefitinib or erlotinib. These EGFR-dependent tumors eventually become TKI resistant, and the common secondary T790M mutation accounts for half the tumors with acquired resistance to gefitinib. However, the key proapoptotic proteins involved in TKI-induced cell death and other secondary mutations involved in resistance remain unclear. The objective of this study was to identify the mechanism of EGFR TKI-induced apoptosis and secondary resistant mutations that affect this process. Methods and Findings: To study TKI-induced cell death and mechanisms of resistance, we used lung cancer cell lines (with or without EGFR mutations), Ba/F3 cells stably transfected with EGFR mutation constructs, and tumor samples from a gefitinib-resistant patient. Here we show that up-regulation of the BH3-only polypeptide BIM (also known as BCL2-like 11) correlated with gefitinib-induced apoptosis in gefitinib-sensitive EGFR-mutant lung cancer cells. The T790M mutation blocked gefitinib-induced up-regulation of BIM and apoptosis. This blockade was overcome by the irreversible TKI CL-387,785. Knockdown of BIM by small interfering RNA was able to attenuate apoptosis induced by EGFR TKIs. Furthermore, from a gefitinib-resistant patient carrying the activating L858R mutation, we identified a novel secondary resistant mutation, L747S in cis to the activating mutation, which attenuated the up-regulation of BIM and reduced apoptosis. Conclusions: Our results provide evidence that BIM is involved in TKI-induced apoptosis in sensitive EGFRmutant cells and that both attenuation of the up-regulation of BIM and resistance to gefitinibinduced apoptosis are seen in models that contain the common EGFR T790M and the novel L747S secondary resistance mutations. These findings also suggest that induction of BIM may have a role in the treatment of TKI-resistant tumors

Derrames pleurais idiopáticos : características e evolução dos pacientes

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Rapidly fatal advanced EGFR -mutated lung cancers and the need for rapid tumor genotyping in clinical practice

Use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is associated with dramatic, durable, and tolerable responses and side effect profiles, respectively, when applied for palliation of advanced EGFR-mutated non-small-cell lung cancers (NSCLCs). Expert guidelines recommend that EGFR mutation testing results should be available within 10 working days of receipt of tumor specimen by the testing laboratory; in circumstances where the tumor specimen needs to be sent to an external laboratory for testing, the sample should be sent within 3 working days of receiving the request for testing. We report here 2 cases, out of 109 EGFR-mutated (exon 19 deletion or L858R) NSCLCs seen at our institution, experiencing rapid clinical deterioration and death within the window of time prescribed by consensus testing guidelines. We hypothesize that a faster turn-around time may have changed the clinical outcome. Improving rapid turnaround times for tumor genotyping may afford more optimal palliation vis-à-vis early initiation of oral targeted therapy in patients with advanced EGFR-mutated NSCLC

Xylopine Induces Oxidative Stress and Causes G 2

Xylopine is an aporphine alkaloid that has cytotoxic activity to cancer cells. In this study, the underlying mechanism of xylopine cytotoxicity was assessed in human colon carcinoma HCT116 cells. Xylopine displayed potent cytotoxicity in different cancer cell lines in monolayer cultures and in a 3D model of cancer multicellular spheroids formed from HCT116 cells. Typical morphology of apoptosis, cell cycle arrest in the G2/M phase, increased internucleosomal DNA fragmentation, loss of the mitochondrial transmembrane potential, and increased phosphatidylserine externalization and caspase-3 activation were observed in xylopine-treated HCT116 cells. Moreover, pretreatment with a caspase-3 inhibitor (Z-DEVD-FMK), but not with a p53 inhibitor (cyclic pifithrin-α), reduced xylopine-induced apoptosis, indicating induction of caspase-mediated apoptosis by the p53-independent pathway. Treatment with xylopine also caused an increase in the production of reactive oxygen/nitrogen species (ROS/RNS), including hydrogen peroxide and nitric oxide, but not superoxide anion, and reduced glutathione levels were decreased in xylopine-treated HCT116 cells. Application of the antioxidant N-acetylcysteine reduced the ROS levels and xylopine-induced apoptosis, indicating activation of ROS-mediated apoptosis pathway. In conclusion, xylopine has potent cytotoxicity to different cancer cell lines and is able to induce oxidative stress and G2/M phase arrest, triggering caspase-mediated apoptosis by the p53-independent pathway in HCT116 cells

Chemical composition, larvicidal and cytotoxic activity of Annona salzmannii (Annonaceae) seed oil

The seed oil of Annona salzmannii A. DC. was analyzed by GC-MS and 1 H qNMR, revealing a mixture of unsaturated (80.5%) and saturated (18.7%) fatty acids. Linoleic (45.3%) and oleic (33.5%) acid were the major unsaturated fatty acids identified, while palmitic acid (14.3%) was the major saturated fatty acid. The larvicidal effects of A. salzmannii seed oil were evaluated against third-instar larvae of Aedes aegypti (Linn.). The oil exhibited moderate larvicidal activity, with aLC50 of 569.77 ppm (95% CI = 408.11 to 825.88 ppm). However, when the cytotoxic effects of the oil were evaluated, no expressive antiproliferative effects were observed in tumor cell lines B16-F10 (mouse melanoma), HepG2 (human hepatocellular carcinoma), K562 (human chronic myelocytic leukemia), HL-60 (human promyelocytic leukemia), and non-tumor cell line PBMC (peripheral blood mononuclear cells), with IC50 values > 50 μg·mL-1. This is the first study to evaluate the chemical composition, larvicidal and cytotoxic activity of A. salzmannii seed oil

Experience with targeted next generation sequencing for the care of lung cancer: Insights into promises and limitations of genomic oncology in day-to-day practice

Introduction Tumor genotyping using single gene assays (SGAs) is standard practice in advanced non-small-cell lung cancer (NSCLC). We evaluated how the introduction of next generation sequencing (NGS) into day-to-day clinical practice altered therapeutic decision-making. Methods Clinicopathologic data, tumor genotype, and clinical decisions were retrospectively compiled over 6 months following introduction of NGS assay use at our institution in 82 patient-tumor samples (7 by primary NGS, 22 by sequential SGAs followed by NGS, and 53 by SGAs). Results SGAs identified abnormalities in 34 samples, and all patients with advanced EGFR-mutated or ALK-rearranged tumors received approved tyrosine kinase inhibitors (TKIs) or were consented for clinical trials. NGS was more commonly requested for EGFR, ALK, and KRAS-negative tumors (p<0.0001). NGS was successful in 24/29 (82.7%) tumors. Of 17 adenocarcinomas (ACs), 11 (7 from patients with ≤15 pack-years of smoking) had abnormalities in a known driver oncogene. This led to a change in decision-making in 8 patients, trial consideration in 6, and off-label TKI use in 2. Of 7 squamous cell (SC) carcinomas, 1 had a driver aberration (FGFR1); 6 had other genomic events (all with TP53 mutations). In no cases were clinical decisions altered (p=0.0538 when compared to ACs). Conclusions Targeted NGS can identify a significant number of therapeutically-relevant driver events in lung ACs; particularly in never or light smokers. For SC lung cancers, NGS is less likely to alter current practice. Further research into the cost effectiveness and optimal use of NGS and improved provider training in genomic oncology are warranted