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Knowing how a bioactive compound interacts with cell membranes is important to understand its effect at the molecular level. In this sense, this work aimed to study the interaction of lysicamine, an alkaloid with action against lung cancer cell lines, with lipid monolayers as cell membrane models. We employed two lipid mixtures: the first composed of 35% DOPC, 30% DOPE, 20% sphingomyelin, and 15% cholesterol as healthy cell membranes models (MM1), and the second replacing DOPC with DOPS as cancer cells models (MM2). The interaction of lysicamine with the monolayers was evaluated using tensiometry, Brewster angle microscopy (BAM), and polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). Lysicamine had interfacial effects in both membrane models. For MM 1, it expanded the lipid monolayer and changed the interfacial rheological properties, increasing the in-plane elasticity of the films. PM-IRRAS spectra suggested a higher conformational disorder of the alkyl chains of the lipids. For MM 2, lysicamine also shifted the isotherms to higher areas, expanding the monolayers, but with no significant alteration in their interfacial rheological properties. PM-IRRAS spectra also suggested higher disorder in the orientation of the lipid alkyl chains upon lysicamine incorporation. For both models, BAM did not show alteration in interfacial aggregation upon drug incorporation. In conclusion, changes in some interfacial properties of membrane models caused by lysicamine depend on the monolayer composition, which can be associated with its bioactivity in cellular membranes.

Lysicamine, an alkaloid with tumorigenic activity, was incorporated in cell membrane models made of lipid Langmuir monolayers. Dipalmitoylphosphocholine (DPPC), dioleoylphosphocholine (DOPC), and palmitoyloleoylcholine (POPC) represented non-tumorigenic cell membranes, and dipalmitoylphosphoserine (DPPS), dioleoylphosphoserine (DOPS), and palmitoyloleoylserine (POPS), tumorigenic ones. The monolayers were characterized by tensiometry, infrared spectroscopy, and Brewster Angle Microscopy (BAM). No significant shifts of the isotherms were observed for the saturated lipids (DPPC and DPPS), while for the others (DOPC, POPS, DOPS, and POPS), more significant changes were observed not only in the compression isotherms but also in the surface pressure-time curve for pre-compressed monolayers. The molecular organization, as well as the morphology of the drug-lipid monolayers, could be inferred with infrared spectroscopy and BAM. While the first revealed that the alkyl chain ordering changed upon lysicamine incorporation, the second showed how the drug could distinctly change the state of aggregation of molecular domains at the air-water interface. In conclusion, lysicamine could interact distinctly with each lipid at the air-water interface, showing the dependence not only on the lipid polar groups but also on the level of unsaturation of the alkyl chains.

Um dos grandes desafios das atuais pesquisas envolvendo a manipulação de arquivos MIDI SMF, é a carência tanto de material didático específico para descrição do protocolo MIDI quanto de um sistema computacional baseado em uma linguagem aderente ao paradigma musical. Este trabalho foi desenvolvido com o objetivo de suprir esta deficiência, na medida em que cria ferramentas didáticas para manipulação de arquivos MIDI utilizando linguagem funcional CLEAN, a qual se mostra bastante aderente ao paradigma musical. Outro fator que determinou escolha por esta linguagem se deu pela velocidade e eficiência que a mesma possui na manipulação de listas, tanto ao utilizar as ferramentas básicas como, principalmente, ao utilizar a notação Zermelo-Frankel. O sistema, portanto, disponibiliza todas as ferramentas básicas de leitura dos arquivos MIDI padrões, e gera como produto final, um arquivo texto contendo todas as informações encontradas na música registrada One of the greatest challenges of the present research involving the manipulation of MIDI SMF archives is the lack of specific instructional material, as in the description of the MIDI protocol, as for a computing system, which bears an adherent music language on the musical paradigm. The present work was developed with the objective to contribute to solve that need, creating instructing tools for the manipulation of MIDI archives using the a functional language CLEAN, which shows itself enough adherent on to the musical paradigm. Another choice factor for the present language took into account its great deal of speed and efficiency in the manipulation of the lists, as to the use of the main basic tools and as to the use of the Zermelo-Frankel notation. The system, makes available all the basic reading tools of the standard MIDI archives and produces, as a final product, a text archive which contains all information found in the recorded music Dissertação (Mestrado)

Esta pesquisa investiga as possibilidades de iniciação aos instrumentos de cordas dedilhadas por meio da improvisação livre. Ela divide-se em três partes: fundamentação teórica, oficinas de improvisação livre e elaboração de um caderno de iniciação. A reflexão teórica tem como principais referências, as pesquisas de Rogério L. M. Costa e H. J. Koellreutter a cerca da Improvisação Livre, e as investigações de Flávia M. Cruvinel sobre o Ensino Coletivo de Instrumentos Musicais. Os diversos tipos de gestos musicais são descritos com enfoque no gesto instrumental, termo adotado na pesquisa para representar os elementos da técnica instrumental. Os gestos instrumentais foram selecionados através de seis oficinas de improvisação livre realizadas nos Conservatórios Estaduais de Música do Triângulo Mineiro, onde se procurou uma forma de registro gráfico musical que favorecesse a prática da improvisação livre e colaborasse no desenvolvimento de um caderno de iniciação aos instrumentos de cordas dedilhadas. Esta nova proposta de iniciação instrumental divide-se em seis partes através da sugestão de roteiros para improvisação livre, grafados de forma não tradicional, com o objetivo de estimular a exploração sonora e timbrística em sintonia com a música da contemporaneidade. Através da criação, da liberdade gestual e da expansão da escuta, permite ao aprendiz desenvolver habilidades instrumentais e musicais para a criação de seu próprio repertório, de acordo com sua identidade, sua biografia, sua experiência de vida. This research investigates the possibilities of initiation to plucked strings instruments through free improvisation. It is divided into three parts: theoretical foundation, free improvisation workshops and notebook initiation. The theoretical reflection has as main references the research of Rogério L. M. Costa and H. J. Koellreutter about Free Improvisation and Flávia M. Cruvinel investigations on Collective Teaching of Musical Instruments. The various kinds of musical gestures are described focusing on instrumental gesture, term adopted in the research to represent the elements of instrumental technique. The instrumental gestures were selected during six free improvisation workshops held in music conservatories in the state of Minas Gerais, where he sought a form of musical graphic record favoring the practice of free improvisation and collaborate into the development of a notebook initiation to plucked strings instruments. This new instrumental initiation proposal is divided into six parts that suggest a guide for free improvisation, written in a nontraditional way, with the aim of stimulating sound and timbre exploration combined with the contemporary music. Through the creation of the gestural freedom and the expansion of listening abilities, it seems likely that could develop musical and instrumental skills to create his/her own repertoire, according to his identity, his biography and life experience.