XILOGRAVURA E MONOTIPIA COMO FORMA DE EXPRESSÃO: MARCAS E MEMÓRIAS

O presente artigo discorre sobre gravura, particularmente monotipia e xilogravura no contexto da arte/educação. São nele apresentados os dados da pesquisa de conclusão do curso de Licenciatura em Artes Visuais, feita através do PIBID ─ Programa Institucional de Bolsa de Iniciação à Docência ─ subprojeto Artes Visuais, na Escola Municipal Eugênio Nelson Ritzel, em Novo Hamburgo. O PIBID, programa vinculado à CAPES, tem por objetivo apoiar a iniciação à docência de estudantes de licenciatura, contribuindo na formação de professores e na melhoria da qualidade da Educação Básica. Neste trabalho, é apresentado o processo de criação desenvolvido pelo grupo de alunos que frequentou as oficinas, tendo sido possível perceber que, em cada encontro, o grupo ficou envolvido com novas descobertas e possibilidades que a técnica enseja e como a pesquisa possibilitou uma ampliação de conhecimento e percepção em relação à arte, à educação e à autora. Palavras chave: Gravura. Monotipia. Xilogravura. Arte. Educação

XILOGRAVURA E MONOTIPIA COMO FORMA DE EXPRESSÃO: MARCAS E MEMÓRIAS

O presente artigo discorre sobre gravura, particularmente monotipia e xilogravura no contexto da arte/educação. São nele apresentados os dados da pesquisa de conclusão do curso de Licenciatura em Artes Visuais, feita através do PIBID ─ Programa Institucional de Bolsa de Iniciação à Docência ─ subprojeto Artes Visuais, na Escola Municipal Eugênio Nelson Ritzel, em Novo Hamburgo. O PIBID, programa vinculado à CAPES, tem por objetivo apoiar a iniciação à docência de estudantes de licenciatura, contribuindo na formação de professores e na melhoria da qualidade da Educação Básica. Neste trabalho, é apresentado o processo de criação desenvolvido pelo grupo de alunos que frequentou as oficinas, tendo sido possível perceber que, em cada encontro, o grupo ficou envolvido com novas descobertas e possibilidades que a técnica enseja e como a pesquisa possibilitou uma ampliação de conhecimento e percepção em relação à arte, à educação e à autora.Palavras chave: Gravura. Monotipia. Xilogravura. Arte. Educação

Designed polyelectrolyte shell on magnetite nanocore for dilution-resistant biocompatible magnetic fluids.

Magnetite nanoparticles (MNPs) coated with poly(acrylic acid-co-maleic acid) polyelectrolyte (PAM) have been prepared with the aim of improving colloidal stability of core-shell nanoparticles for biomedical applications and enhancing the durability of the coating shells. FTIR-ATR measurements reveal two types of interaction of PAM with MNPs: hydrogen bonding and inner-sphere metal-carboxylate complex formation. The mechanism of the latter is ligand exchange between uncharged -OH groups of the surface and -COO(-) anionic moieties of the polyelectrolyte as revealed by adsorption and electrokinetic experiments. The aqueous dispersion of PAM@MNP particles (magnetic fluids - MFs) tolerates physiological salt concentration at composition corresponding to the plateau of the high-affinity adsorption isotherm. The plateau is reached at small amount of added PAM and at low concentration of nonadsorbed PAM, making PAM highly efficient for coating MNPs. The adsorbed PAM layer is not desorbed during dilution. The performance of the PAM shell is superior to that of poly(acrylic acid) (PAA), often used in biocompatible MFs. This is explained by the different adsorption mechanisms; metal-carboxylate cannot form in the case of PAA. Molecular-level understanding of the protective shell formation on MNPs presented here improves fundamentally the colloidal techniques used in core-shell nanoparticle production for nanotechnology applications

The biological in vitro effect and selectivity of aromatic dicationic compounds on Trypanosoma cruzi

Trypanosoma cruzi is a parasite that causes Chagas disease, which affects millions of individuals in endemic areas of Latin America. One hundred years after the discovery of Chagas disease, it is still considered a neglected illness because the available drugs are unsatisfactory. Aromatic compounds represent an important class of DNA minor groove-binding ligands that exhibit potent antimicrobial activity. This study focused on the in vitro activity of 10 aromatic dicationic compounds against bloodstream trypomastigotes and intracellular forms of T. cruzi. Our data demonstrated that these compounds display trypanocidal effects against both forms of the parasite and that seven out of the 10 compounds presented higher anti-parasitic activity against intracellular parasites compared with the bloodstream forms. Additional assays to determine the potential toxicity to mammalian cells showed that the majority of the dicationic compounds did not considerably decrease cellular viability. Fluorescent microscopy analysis demonstrated that although all compounds were localised to a greater extent within the kinetoplast than the nucleus, no correlation could be found between compound activity and kDNA accumulation. The present results stimulate further investigations of this class of compounds for the rational design of new chemotherapeutic agents for Chagas disease

Phenolic 1,3-diketones attenuate lipopolysaccharide-induced inflammatory response by an alternative magnesium-mediated mechanism

Background and Purpose: Toll-like receptor 4 (TLR4) plays a key role in the induction of inflammatory responses both in peripheral organs and the CNS. Curcumin exerts anti-inflammatory functions by interfering with LPS-induced dimerization of TLR4\ue2\u80\u93myeloid differentiation protein-2 (MD-2) complex and suppressing pro-inflammatory mediator release. However, the inhibitory mechanism of curcumin remains to be defined. Experimental Approach: Binding of bis-demethoxycurcumin (GG6) and its cyclized pyrazole analogue (GG9), lacking the 1,3-dicarbonyl function, to TLR4\ue2\u80\u93MD-2 was determined using molecular docking simulations. The effects of these compounds on cytokine release and NF-\uce\ubaB activation were examined by ELISA and fluorescence staining in LPS-stimulated primary microglia. Interference with TLR4 dimerization was assessed by immunoprecipitation in Ba/F3 cells. Key Results: Both curcumin analogues bound to the hydrophobic region of the MD-2 pocket. However, only curcumin and GG6, both possessing the 1,3-diketone moiety, inhibited LPS-induced TLR4 dimerization, activation of NF-\uce\ubaB and secretion of pro-inflammatory cytokines in primary microglia. Consistent with the ability of 1,3-diketones to coordinate divalent metal ions, LPS stimulation in a low magnesium environment decreased pro-inflammatory cytokine release and NF-\uce\ubaB p65 nuclear translocation in microglia and decreased TLR4\ue2\u80\u93MD-2 dimerization in Ba/F3 cells. Curcumin and GG6 also significantly reduced cytokine output in contrast to the pyrazole analogue GG9. Conclusions and Implications: These results indicate that phenolic 1,3-diketones, with a structural motif able to coordinate magnesium ions, can modulate LPS-mediated TLR4\ue2\u80\u93MD-2 signalling. Taken together, these studies identify a previously uncharacterized mechanism involving magnesium, underlying the inflammatory responses to LPS