7 research outputs found
Investimento em Projetos com Base no Planejamento Estratégico: Um Estudo de Caso em uma Fábrica de Carrinhos para Supermercado
<p>O presente artigo tem por objetivo apresentar um estudo sobre a importância do planejamento e a busca de informações úteis e precisas na hora de investir em projetos, demonstrando a necessidade de alinhar as decisões aos objetivos estratégicos da empresa. Inicialmente, através de uma revisão da literatura acerca do tema abordado, foram apresentados os principais conceitos e definições sobre os critérios de análise de investimentos considerados mais relevantes e sobre planejamento estratégico. A partir disso, através da aplicação dos critérios, buscou-se demonstrar a viabilidade de um investimento para a ampliação das atividades na empresa Zincar Indústria e Comercio de Carrinhos para Supermercado Ltda, localizada na região sudoeste do Paraná, visando oferecer subsídios para a tomada de decisões por parte dos gestores, através do alinhamento das decisões com a estratégia corporativa da empresa.</p><p><strong>DOI:10.5585/gep.v3i3.113</strong></p
Structure and properties of thermoplastic polyurethanes based on poly(dimethylsiloxane): Assessment of biocompatibility
Properties and biocompatibility of a series of thermoplastic
poly(urethane-siloxane)s (TPUSs) based on alpha,omega-dihydroxy ethoxy
propyl poly(dimethylsiloxane) (PDMS) for potential biomedical
application were studied. Thin films of TPUSs with a different PDMS soft
segment content were characterized by H-1 NMR, quantitative C-13 NMR,
Fourier transform infrared spectroscopy (FTIR), atomic force microscopy
(AFM), differential scanning calorimetry (DSC), dynamic mechanical
analysis (DMA), contact angle, and water absorption measurements.
Different techniques (FTIR, AFM, and DMA) showed that decrease of PDMS
content promotes microphase separation in TPUSs. Samples with a higher
PDMS content have more hydrophobic surface and better waterproof
performances, but lower degree of crystallinity. Biocompatibility of
TPUSs was examined after attachment of endothelial cells to the
untreated copolymer surface or surface pretreated with multicomponent
protein mixture, and by using competitive protein adsorption assay.
TPUSs did not exhibit any cytotoxicity toward endothelial cells, as
measured by lactate dehydrogenase and
3-{[}4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide assays.
The untreated and proteins preadsorbed TPUS samples favored endothelial
cells adhesion and growth, indicating good biocompatibility. All TPUSs
adsorbed more albumin than fibrinogen in competitive protein adsorption
experiment, which is feature regarded as beneficial for
biocompatibility. The results indicate that TPUSs have good surface,
thermo-mechanical, and biocompatible properties, which can be tailored
for biomedical application requirements by adequate selection of the
soft/hard segments ratio of the copolymers. (C) 2013 Wiley Periodicals,
Inc.Ministry of Education, Science and Technological Development of the
Republic of Serbia {[}172062
A novel C,D-spirolactone analogue of paclitaxel: autophagy instead of apoptosis as a previously unknown mechanism of cytotoxic action for taxoids
The design, synthesis and biological evaluation of a novel C, D-spirolactone analogue of paclitaxel is described. This is the first paclitaxel analogue without an oxetane D-ring that shows a significant cytotoxic effect (activity one order of magnitude lower than paclitaxel). More importantly, its cytotoxicity is a result of a different mechanism of action, involving mTOR inhibition-dependent autophagy instead of G(2)/M cell cycle arrest-dependent apoptosis
Metformin reduces cisplatin-mediated apoptotic death of cancer cells through AMPK-independent activation of Akt
Metformin is an antidiabetic drug with anticancer properties, which mainly acts through induction of AMP-activated protein kinase (AMPK). In the present study we investigated the influence of metformin on the in vitro anticancer activity of the well-known chemotherapeutic agent cisplatin. Cell viability was determined by MTT and LDH release assay, oxidative stress and apoptosis (caspase activation, DNA fragmentation, and phosphatidylserine exposure) were assessed by flow cytometry, while activation of AMPK and Akt was analyzed by immunoblotting. Although metformin reduced the number of tumour cells when applied alone, it surprisingly antagonized the cytotoxicity of cisplatin towards U251 human glioma, C6 rat glioma, SHSY5Y human neuroblastoma, L929 mouse fibrosarcoma and HL-60 human leukemia cell lines. Only in B16 mouse melanoma cells metformin augmented the cytotoxicity of cisplatin. In U251 glioma cells metformin suppressed cisplatin-induced apoptotic cell death through inhibition of oxidative stress and caspase activation. The observed cytoprotection was apparently AMPK-independent, as metformin did not further increase cisplatin-induced AMPK activation in U251 cells and other pharmacological AMPK activators failed to block cisplatin-mediated apoptosis. On the other hand, metformin induced Akt activation in cisplatin-treated cells and Akt inhibitor 10-DEBC hydrochloride or phosphoinositide 3-kinase/Akt inhibitor LY294002 abolished metformin-mediated antioxidant and antiapoptotic effects. In conclusion, the antidiabetic drug metformin reduces cisplatin in vitro anticancer activity through AMPK-independent upregulation of Akt survival pathway. These data warrant caution when considering metformin for treatment of diabetic cancer patients receiving cisplatin or as a potential adjuvant in cisplatin-based chemotherapeutic regimens. (c) 2010 Published by Elsevier B.V