Avaliação de insumos agrícolas por meio de testes ecotoxicológicos: fase preliminar.

bitstream/item/31076/1/COMUNICADO-134.pd

Between old broadcast media and new networked media: materiality and media consumption practices

Past tensions between content and materiality have prevented communication researchers from forming a deeper conceptualization of the role played by the material character of communication technologies in shaping social arrangements and cultural forms of expression. Drawing on the findings of a comparative research project on European audiences, we examine the interrelation between material facets of media technologies and the practices they afford on the audience side. Relations between "old" mass media, such as television, and "new" networked and individualized media, such as the Internet, are discussed, focusing on the transitions between different media technologies and the processes of substitution or supplementation occurring in these transitions.info:eu-repo/semantics/publishedVersio

Acetylcholinesterase inhibitory activity of oxazole derivatives

Comunicação oral sob a forma de painelAlzheimer’s disease (AD) is the most common form of dementia among persons over 65 years of age. It is a brain neurodegenerative disorder characterised by loss of memory and cognition. Current treatment is symptomatic, with the major therapeutic strategy based on the “cholinergic hypothesis”, specifically acetylcholinesterase (AChE) inhibition. Tacrine (THA) was the first and one of the few drugs approved in the last decade for the treatment of AD. However, due to the important adverse effects, such as hepatotoxicity, it is no longer widely used. Therefore, more potent and less aggressive THA analogues are necessary. This prompted us to evaluate the AChE inhibitory activity of new oxazole derivatives (compounds 1-5), presenting a pyridine ring (compounds 2,3) or a benzene ring (compounds 4,5) in the molecule (1). The biological activity of the compounds was evaluated by measuring the AChE inhibitory activity by an adaptation of the method reported by Ellman et al (2). The reaction rates were compared and the percent of inhibition by the test compounds was calculated. Assays were performed in quadruplicate in at least two independent experiments, and THA was used as a reference compound. At the maximum soluble concentrations, compounds 1 and 2 inhibited AChE activity by nearly 50%, while the inhibition by the derivative 3 was only around 30%. In contrast, the oxazolo-derivatives 4 and 5 were devoid of any inhibitory activity, which we can speculate to be due to the absence of the N atom in the benzene ring in these compounds. Collectively, these preliminary findings point to a potential interest of precursor 1 and THA-derivative 2 for AD therapeutics, although structural modifications are needed to improve the solubility of the compounds, which is an essential step to enhance their activity. References: 1. Carreiras MC, Eleutério A, Marco-Contelles J, unpublished results. 2. Ellman, G. L. et al. Biochem. Pharmacol. 1961; 7: 88-95.Financial support: Centro de Estudos de Ciências Farmacêuticas, Centro de Patogénese Molecular – UBMBE and Instituto de Química Orgánica General – CSIC

Fixed-bed column process as a strategy for separation and purification of Cephamycin C from fermented broth

Fixed-bed column processes using the anionic resin Q Sepharose XL were evaluated for Cephamycin C (CepC) purification from fermentation broth. Breakthrough and desorption curves were obtained for different flow rates (2.5, 5.0 and 7.5 mL/min). The elution method consisted of a stepwise gradient using NaCl solutions (0.1, 0.3 and 0.5%), which resulted in the separation of CepC from others antibiotics. The flow rate did not interfere on adsorption during loading of the column, but band broadening was observed during elution as the flow rate increased. After the ion exchange process, the fractions containing CepC were submitted to solid phase extraction using a C18 cartridge to remove salts. Analyses of the broth used to feed the column and of the salt-free fractions by LC-MS showed a reduction in the concentration of some contaminants (possibly penicillin N, deacetylcephalosporin C, and deacetoxycephalosporin C) compared to the concentration of CepC. In conclusion, ion exchange process followed by adsorption on a C18 adsorbent was demonstrated to be a selective and efficient procedure to purify CepC from fermentation broth.The authors acknowledge CAPES, CNPq, and FAPESP for the financial support

DR(E)SS TO ABACAVIR CONFIRMED BY PATCH TESTS

A reacção de hipersensibilidade (HS) ao abacavir é uma doença sistémica, potencialmente fatal, que ocorre em 2-9% dos doentes expostos. Inicia-se nas primeiras 6 semanas de tratamento e assemelha-se clinicamente ao DRESS, no entanto, sem eosinofilia. A relação desta reacção com o HLA-B*5701 foi definitivamente comprovada quando os casos imputáveis ao abacavir foram confirmados com um teste epicutâneo (TE) positivo. O HLA-B*5701 foi considerado um indicador excelente de HS ao abacavir, com um valor preditivo positivo da ordem dos 55%, pelo que actualmente se recomenda a sua pesquisa antes de iniciar qualquer esquema de tratamento com este fármaco. Relata-se um caso de HS ao abacavir, relembrando a sua semelhança clínica com o DRESS e realçando as suas diferenças, bem como a importância da fenotipagem HLA antes de iniciar o tratamento e a utilidade dos TE, tanto na confirmação da etiologia da reacção imunológica como no estudo dos mecanismos efectores.Abacavir hypersensitivity is a potentially fatal systemic adverse reaction that occurs in 2-9% of exposed patients. Symptoms appear during the first 6 weeks of therapy and are similar to DRESS although usually there is no eosinophilia. Studies have confirmed a positive relation with HLA-B*5701, particularly when only cases confirmed by a positive epicutaneous patch test were considered. This HLA allele is now considered an excellent predictor of abacavir hypersensitivity reaction (55% positive predictive value) and it is mandatory to perform a genetic screening before initiating any HIV treatment with abacavir. We report a case of abacavir hypersensitivity reaction, reminding its clinical resemblance with DRESS and pointing out the differences between these two entities, as well as highlighting the importance of HLA phenotyping before beginning treatment with abacavir and the utility of the patch test in confirming this immunologic reaction and studying its effector mechanisms

The Use of Polypropylene and High-Density Polyethylene on Cork Plastic Composites for Large Scale 3D Printing

Acknowledgements This work is supported by the Fundação para a Ciência e a Tecnologia (FCT) and Centro2020 through the Project references: UID/Multi/04044/2013 and PAMI - ROTEIRO/0328/2013 (Nº 022158). In addition, the authors acknowledge the funding from the project World of Outstanding Wool and Wood (WOWW), POCI-01-0247-FEDER-017574 from the Portuguese National Innovation Agency. The authors gratefully acknowledge to Amorim Cork Composites for the cork powder. We thank Ana O. Tojeira and Ana R. Fonseca for the support provided in performing the laboratorial tests as Laboratory Managing Engineers.This work focuses on studying the possibility of 3D printing of composite materials composed by cork and a polymer matrix (CPC). Initially the cork was mixed with two types of polymers (HDPE and PP) in different proportions and later processed using extrusion and injection. The composites were tested to study the physical, chemical and mechanical properties. The material was then tested on a large-scale 3D printer to study its feasibility and the ability to produce new products through 3D printing. Attention was focused on the use of pure cork, varying the concentration of cork and coupling agent in thermoplastic matrix composites of PP and HDPE. It was demonstrated that the increase of 5wt.% of coupling agent in the two types of polymers significantly improved the mechanical properties and adhesion between the phases but the increase in cork concentration decreased mechanical properties and crystallinity. The CPCs with PP showed to have better mechanical properties, better aesthetic and internal structural quality, and easier processability than those with HDPE matrix. Nevertheless, the HDPE CPCs showed a high degree of crystallization. Concerning 3D printing, it was demonstrated the possibility of making new products based on natural cork fibers, showing promising results, although additional research is still needed to optimize the process.info:eu-repo/semantics/publishedVersio

Multivariate multi-way analysis of multi-source data

Motivation: Analysis of variance (ANOVA)-type methods are the default tool for the analysis of data with multiple covariates. These tools have been generalized to the multivariate analysis of high-throughput biological datasets, where the main challenge is the problem of small sample size and high dimensionality. However, the existing multi-way analysis methods are not designed for the currently increasingly important experiments where data is obtained from multiple sources. Common examples of such settings include integrated analysis of metabolic and gene expression profiles, or metabolic profiles from several tissues in our case, in a controlled multi-way experimental setup where disease status, medical treatment, gender and time-series are usual covariates

Novel solar absorber surfaces with organic pigments

This paper presents results of application of natural and synthetic organic pigments in selective solar absorber coatings. Some of these photo excite pigments were tested like solar radiation absorber pigments in paint coatings and others as a form to increase the absorption of solar radiation in titanium oxide monolayer selective coatings produced by reactive magnetron sputtering. Morphologic aspects and optical properties are discussed as a function of deposition parameters and of formulation parameters. The main goal is to prepare solar absorber surfaces as a tandem of TiOx thin films, organic pigment using a conductive substrate or of paint with organic and/or inorganic pigments and conductive substrate, all reaching great photo thermal conversion efficiency, high durability and low costs to the ending product and stability at medium range temperatures (120-150ºC). The best optical properties for titanium oxide sputtered films were 88% for solar absorption, with 7% of emissivity for deposition parameters of: pulsed frequency 200kHz, reverse time of 0.4μs, discharge current of 0.7A, argon flow rate of 50ml/min and oxygen flow rate changing from 0 to 2.5ml/min. The results obtained with paints were not satisfactory. The best couple values for solar absorption and emissivity were respectively 94%, and 74