Modos projetuais de simulação: uso de ferramentas de simulação térmica no processo projetual de arquitetura

This thesis aims to describe and demonstrate the developed concept to facilitate the use of thermal simulation tools during the building design process. Despite the impact of architectural elements on the performance of buildings, some influential decisions are frequently based solely on qualitative information. Even though such design support is adequate for most decisions, the designer will eventually have doubts concerning the performance of some design decisions. These situations will require some kind of additional knowledge to be properly approached. The concept of designerly ways of simulating focuses on the formulation and solution of design dilemmas, which are doubts about the design that cannot be fully understood nor solved without using quantitative information. The concept intends to combine the power of analysis from computer simulation tools with the capacity of synthesis from architects. Three types of simulation tools are considered: solar analysis, thermal/energy simulation and CFD. Design dilemmas are formulated and framed according to the architect s reflection process about performance aspects. Throughout the thesis, the problem is investigated in three fields: professional, technical and theoretical fields. This approach on distinct parts of the problem aimed to i) characterize different professional categories with regards to their design practice and use of tools, ii) investigate preceding researchers on the use of simulation tools and iii) draw analogies between the proposed concept, and some concepts developed or described in previous works about design theory. The proposed concept was tested in eight design dilemmas extracted from three case studies in the Netherlands. The three investigated processes are houses designed by Dutch architectural firms. Relevant information and criteria from each case study were obtained through interviews and conversations with the involved architects. The practical application, despite its success in the research context, allowed the identification of some applicability limitations of the concept, concerning the architects need to have technical knowledge and the actual evolution stage of simulation tools

Combater as secas e defender as florestas a natureza nos desafios da ciência e da técnica para modernizar o Brasil (1889 a 1934)

In the first decades of 20th century the just instituted Brazilian Republic faced the challenge to modernize the country. Considering that the progress was associated with the exhaustion of the forest reserves and with climatic changes, two big issues were seen as fundamental: To Fight the Droughts and To Defend the Forests; headed by professionals who were dedicated to these ideals. This research starts from the premise that these were the main challenges enforced by nature to the Brazilian development; the general objective was delimited in the search to understand the meaning and the conception of the natural world by this group of professionals who faced the shock between modernizing the country and conserving its natural resources. Aiming to contribute with the construction of the Brazilian environmental history and to bring historical elements to the debate about the environment in the country, the author concentrates his attention to the analyses, the discussions and the actions that preceded the regulation on the use of natural resources and the implementation of the environmental legislation in Brazil, occurred in 1934. The investigation uses as methodological basis the theoretical directions of environmental history, using sources of data still little explored and valued. In such way, it is taken as starting point some published papers about this subject during the period between 1889 and 1934 in two technical magazines the Revista Brazil Ferro-Carril and the Revista do Club de Engenharia. National engineering played a basic role in this process while arguing, projecting and constructing the development. The formulated proposals, after being divulged, had fomented the interchange with other professionals and had favored the advance of ambient questions in Brazil, in the sense to preserve natural resources, to construct more harmonic relations between the society and the nature and to equate the development with the environment preservation

Henri Lefebvre: possibilidades teórico-metodológicas para Arquitetura e urbanismo

This paper presents the theoretical-methodological possibilities of the French philosopher and sociologist Henri Lefebvre, for the discipline of architecture and urbanism in an effort to overcome the fragmentation imposed by the institutionalization of science in general. From Du rural à l'urbain (Lefebvre, 1970) compilation, it brings the author's other works from the period between 1968 and 1974, indicating the conduits for reflection and their interrelationships with methods, types of analyses and other procedures to treat the space-time urban. The methodology involves a research on the author s 'today and yesterday' in the scientific field, a research and analysis of his procedures in highlight of philosophical, social, economic and political aspects, the historical context of his references and provides significant and possible elements for the study, research and extension in the area in question

O Caráter Tectônico do Moderno Brasileiro: Bernardes e Campello na Paraíba (1970-1980)

This study aims to analyze the tectonic character of the works of Sergio Bernardes and Glauco Campello architects, built in Paraiba, between the turn of the decade in 1970 and early 1980 in order to bring reflections about the poetics of construction s importance in the formal structure of the architecture, contributing to the debate about the specificitiesand peculiarities of modern architecture produced in Brazil. The research, using the strategies of the case study, startsfromthe review on the use of "tectonic" by Kenneth Frampton and other scholars of the term, to base the concept and set the analytical parameters of the tectonics. Then it proceeds to the insertion of buildings in the cultural and socio-political Brazilian s context in the periodproposed forstudy, in sequence, analyzesthe works of each architect. The study confirms that the expressive power of Brazilian heroic modern architecture, emphasizing the poetics of construction, sediments a tectonic culture that resonates in the following generations

Projeto em Áreas Consolidadas de Patrimônio Cultural: Propostas para a Construção de uma Metodologia de Ensino

Le thème du patrimoine culturel architectural et urbain continue d avoir une place importante dans le milieu technique et scientifique. Le concept s est élargi et aujourd hui comprend différentes procédures de projets d intervention. L importance accordée au thème amène à l inclusion de la matière de techniques rétrospectives et aux contenus qui en sont liés: conservation, restauration, restructuration et reconstruction d édifices et ensembles urbains, dans les parcours des cours d architecture et d urbanisme au Brésil établies par le Ministère de l Education Nationale (MEC) dans les années quatre-vingt-dix, postérieurement incorporés dans les directrices disciplinaires nationales. Nous partons des discussions théoriques et conceptuelles du Domaine du Patrimoine Culturel, ainsi que des principales théories pédagogiques d enseignements et d apprentissage articulées au projet. Dans ce contexte les objectifs principaux de cette thèse consistent à systématiser et à analyser les principales procédures méthodologiques contribuant pour la construction de méthodes d enseignement tournée vers des activités pratiques dans ce domaine. Pour cela, la recherche a été systématisée dans une approche à deux niveaux. En ce qui concerne le premier, basé sur des données secondaires, neuf cours d architecture et urbanisme ont étés identifiés entre institutions publiques d enseignement supérieur dont huit brésiliennes et une française, considérées représentatives en ce qui concerne les pratiques d enseignement de projet et de patrimoine culturel. Trente disciplines dédiées à la matière ont été également reconnues initialement, et postérieurement, cinq disciplines qui possèdent un emploi du temps dédié à la pratique de projet ont aussi été reconnues. Dans le deuxième cas, basée sur des données primaires, ont étés analysées les méthodologies et les stratégies d enseignement de projet basées sur les définitions des matières et des autres éléments des plans de travail avec des observations, des entrevues et des questionnaires en trois ateliers. Par rapport aux résultats nous avons constaté que toutes les écoles possèdent les contenus de la matière, mais peu d entre elles privilégient la relation du projet appliqué au patrimoine culturel. Nous avons constaté que les questions des projets dans ce contexte, même s elles sont considérées complexes, ont privilégié le listage et l analyse du site. L atelier qui intègre les fondements des théories de préservation, l histoire de l architecture et urbanisme et techniques anciennes et actuelles, est mis en valeur comme un modèle cohérent avec les propositions d intégration des connaissances théoriques et pratiques du projet appliqué à la discipline. Basé sur ces constatations il est possible de démontrer quatre étapes du projet appliqué au patrimoine culturel: 1ª) les fondements généraux qui concernent les bases théoriques sur la préservation, histoire et technique rétrospective, par exemple, l appropriation de lois et normes et la sensibilisation de l élève sur les questions de patrimoine culturel; 2ª) le contacte avec la réalité qui inclut l appropriation du problème à partir de ces acteurs, de ces échelles, de cette lecture de site et l analyse de l objet d étude; 3ª) le développement de la proposition qui inclut programmes (fonctions existantes et propositions), définitions du partit (types d intervention), conception (hypothèse et discussion) et définition de proposition; 4ª) la finalisation du projet qui consiste à développer la proposition avec sa représentation graphique et sa présentation finale. Nous concluons que le projet en Domaine du Patrimoine Culturel demande une attention spéciale et doit être présent dans les cursus considérant les principes généraux nécessaires à la formation de l élève. Le binôme projet / patrimoine signifie avoir dans le cursus universitaire les contenus et questions nécessaires les connaissances, les variables et possibilités existantes dans le projet appliqué au patrimoine culturel de façon à ce que ces connaissances soient incorporées dans l exercice de projet et n apparaissent pas comme un simple contenu théorique sans articulation avec la pratique. Naturellement ces conclusions n épuisent pas la réflexion sur la question. Nous espérons que les analyses faites contribuent à définir des méthodologies d enseignements capables d êtres vérifiées et testées dans la pratique en salle de cours, et puisse collaborer avec les nouvelles recherches surtout celles qui ont pour but des nouvelles théories pédagogiques d enseignement apprentissage du projet en Domaine du Patrimoine Culturel

Do modelo geométrico ao modelo físico: o tridimensional na educação do arquiteto e urbanista

In the teaching practice of architecture and urbanism in Brazil, educational legislation views modeling laboratories and workshops as an indispensable component of the infrastructure required for the good functioning of any architectural course of study. Although the development of information technology at the international level has created new possibilities for digital production of architectural models, research in this field being underway since the early 1990s, it is only from 2007 onwards that such technologies started to be incorporated into the teaching activity of architecture and urbanism in Brazil, through the pioneering experience at LAPAC/FEC/UNICAMP. It is therefore a recent experiment whose challenges can be highlighted through the following examples: (i) The implementation of digital prototyping laboratories in undergraduate courses of architecture and urbanism is still rare in Brazil; (ii) As a new developing field with few references and application to undergraduate programs, it is hard to define methodological procedures suitable for the pedagogical curricula already implemented or which have already been consolidated over the years; (iii) The new digital ways for producing tridimensional models are marked with specificities which make it difficult to fit them within the existing structures of model laboratories and workshops. Considering the above, the present thesis discusses the tridimensional model as a tool which may contribute to the development of students skills in perceiving, understanding and representing tridimensional space. Analysis is made of the relation between different forms of models and the teaching of architectural project, with emphasis on the design process. Starting from the conceptualization of the word model as it is used in architecture and urbanism, an attempt is made to identify types of tridimensional models used in the process of project conception, both through the traditional, manual way of model construction as well as through the digital ones. There is also an explanation on how new technologies for digital production of models through prototyping are being introduced in undergraduate academic programs of architecture and urbanism in Brazil, as well as a review of recent academic publications in this area. Based on the paradigm of reflective practice in teaching as designed by Schön (2000), the experiment applied in the research was undertaken in the integrated workshop courses of architectural project in the undergraduate program of architecture and urbanism at Universidade Federal do Rio Grande do Norte. Along the experiment, physical modeling, geometric modeling and digital prototyping are used in distinct moments of the design process with the purpose of observing the suitability of each model to the project s phases. The procedures used in the experiments are very close to the Action Research methodology in which the main purpose is the production of theoretical knowledge by improving the practice. The process was repeated during three consecutive semesters and reflection on the results which were achieved in each cycle helped enhancing the next one. As a result, a methodological procedure is proposed which consists of the definition of the Tridimensional Model as the integrating element for the contents studied in a specific academic period or semester. The teaching of Architectural Project as it is developed along the fifth academic period of the Architecture and Urbanism undergraduate program of UFRN is taken as a reference

O projeto de arquitetura de espaços temporários com o uso de sistema construtivo remontável: um estudo exploratório

The purpose of this research is to study the portable or reassemblable architectures, which, different from conventional architecture (whose designs are of permanent buildings), corresponds to the designing of spaces with temporary purposes. The focus of the study is the architectural design of spaces that are produced from building systems that can to be moved to different places (process of assembly / disassembly / reassembly) in order to identify the types of spaces generated and the processes used in their design / projecting. The aim is to investigate relationships between the initial project conceived based on a Reassemblable Construction System (RCS) and its application in the architectural design of professionals and students in order to contribute to the understanding of the specificities of this type of design activity. To this end it was developed the exploratory research based on multimedia methods, which includes: documentary analysis, technical visits, interviews, surveys, academic exercise and documentation by images. Although the study is not conclusive, the results indicate significant differences between the point of view of the RCS´s designers and its users (architects and architecture students) since the users demonstrated to have some difficulty to access the features provided for the first group, in particular the students. It is also demonstrated that the use of RCSs seems to change the appreciation / hierarchization of the conditions of project design, since, unlike what happens in traditional architectural design, the designers who use them seem to be more concerned with constructive issues, especially the structural elements (support and covering), instead of functionality, aesthetics and even physical characteristics of the site

Outorga onerosa do direito de construir e dinâmica do mercado imobiliário formal: planejamento e descaminhos na expansão urbana de Parnamirim RN (2008-2010)

The `Outorga Onerosa do Direito de Construir - OODC` (Public Concession of Building Rights), instrument instituted by The City Statute in 2001, has as main objective the recovery of urban property, seeking for a fair distribution the urbanization benefits. The possibility of usage of the OODC instrument is linked to the maximum utilization coefficient, determined to specific areas in accordance to existing infrastructure conditions, further taking into account the formal real estate market, expansion axis and crowding. Being an instrument which establishes values to be paid for a better use of land, it maintains a narrow relation to the real estate, incentivizing or discouraging the crowding in specific areas. The present study investigates the relationship between the criteria for the making of the Public Concession of Building Rights instrument and the dynamics of the formal real estate market. It takes as empiric universe Parnamirim (RN), part of the Natal Metropolitan Area (RN), focusing on the application of the OODC in the period of 2008-2010. It seeks to better understand the necessary basis for the formulation of the instrument, about how it works and its relation to the formal real estate market. It aims to depict the formal real estate market by presenting the production of urban space in Parnamirim in terms of intensity and nature of the real estate, furthermore identifying the licensed properties through the application of the municipality instrument. For the conclusion, it is discussed the criteria for the formation of OODC, its relationship to the dynamics of the formal real estate market and its influencing possibilities in the processes of usage and occupation of land in the context of urban planning

Permanências e perspectivas no ensino de projeto de arquitetura no Brasil: uma análise a partir da produção científica dos Seminários UFRGS (1985) e Projetar (2003-2011)

O objeto de estudo desta tese é o ensino de projeto de arquitetura no contexto acadêmico brasileiro. O trabalho procura analisar esse objeto nos aspectos relativos ao ensinar a fazer e ao aprender a fazer , por meio de uma perspectiva epistemológica e cognitiva, a partir da produção científica dos Seminários UFRGS (1985) e Projetar (2003-2011) sob o olhar de três estados constitutivos: conservação, permanência e transformação. A metodologia de investigação é qualitativa e seus pressupostos são investigad os por meio do método hipotético-dedutivo em busca de um conhecimento aproximativo. Dentro do universo pesquisado, as hipóteses conduzem: primeiro, à investigação e caracterização de estruturas que se conservam; segundo, à investigação e levantamento de valores e conceitos que permanecem adequados por sua capacidade de adaptação às mudanças e paradigmas; e, terceiro, por procurarem destacar práticas pedagógicas que indicam novos caminhos na maneira de agir e de se pensar o ensino de projeto de arquitetura. A pesquisa demonstrou que, embora em menores proporções, ainda se conservam ações e posturas pedagógicas que: valorizam os ideais funcionalistas e racionalistas da arquitetura; adotam posturas deterministas, caminhos prescritivos ou intuitivos no ensino da concepção arquitetural; não apresentam clareza metodológica na abordagem da problemática arquitetônica; os contextos urbanos são pouco explorados na experimentação; utilizam um sistema de concepção baseado em princípios estéticos canônicos e universais, sem problematizar as causas da transformação da arquitetura contemporânea e qual o seu papel numa sociedade complexa e diversificada. Com relação às novas perspectivas encontradas, a análise da produção científica demonstrou que a prática pedagógica do ensino de projeto de arquitetura no Brasil passa por transformações críticas valiosas. Essa constatação foi percebida, por meio, também, de reflexões e de práticas pedagógicas que valorizam a integração de conteúdos; que possuem um discurso crítico e conciliador com relação à necessidade de renovação de práticas, paradigmas, meios e conteúdos; que estão abertas às posturas cooperativas e às estratégias para a constituição de um corpo teórico-prático para o ensino do projeto que não se limite ao campo da arquitetura; que reconhecem a importância das novas tecnologias computacionais na concepção projetual e no ensino do projeto, assim como, as tecnologias e estratégias que atualizam as soluções projetuais no uso adequado dos recursos ambientais; que consideram o espaço acadêmico como um lugar propício para as experiências projetuais e pedagógicas; que manifestam um esforço em considerar a participação do usuário, assim como em realizar um processo de apreensão de contextos complexos como objeto de estudo, adotando uma postura de valorização do processo projetual. O trabalho conclui que a educação do arquiteto deve estar atenta aos aspectos relativos à inclusão da realidade sociocultural e ambiental como referência para o fazer arquitetural em detrimento da primazia dada à racionalidade técnica, uma vez que essa realidade permite a mediação, entre o ser e o mundo , como uma estratégia que supera qualquer antecipação programática e viabiliza a transformação e a construção do próprio ser e do mundo . Assim, se o aprender fazendo é necessário para a formação do arquiteto, que esse fazer seja refletido e retroalimente a prática

Percepção Ambiental em Museus Paisagens de Arte Contemporânea: a legibilidade dos museus Inhotim/Brasil e em Serralves/Portugal avaliada pelo público/visitante

This thesis nalyzes the wayfinding in Landscape Museum of Contemporary Art (MPAC), based on the Institute of Contemporary Art CACI, Minas Gerais, Brazil and the Museum of Contemporary Art of the Serralves Foundation, Porto, Portugal. The study focuses on the interrelationship of the public/visitors with the landscape, architecture and contemporary art museums in these, in order to understand visual perception and apprehension of such an environment for their users. For both were confronted documentation (visual and written) and people talk. The main hypothesis put forward is that the audience/visitor MPAC appreciates the interrelationship between the natural environment (park/garden) and built environment (the works of contemporary art and the galleries), giving equal value to both. To complement this, a second hypothesis is that during the visit to MPACS, visitors define their paths spontaneously, but strongly influenced by existing visual indicators (maps, signage and striking landscape elements), which facilitate the readability of space, which also contribute to the offered services and the experiences of similar institutions. The analytical basis of the research used the concepts of legibility (LYNCH, 2009), wayfinding (GIBSON, 2009; ARTHUR, PASSINI, 2002; WEISMAN, 1982), Experiential Cotinnum (TUAN, 1985), Space Bound (CRUZ PINTO, 2007) and habitus (BOURDIEU, 1992). Methodologically was used qualitative research (DEMO 2000) by means of a case study (YIN, 2005; STAKE, 1999) and participant observation (WHYTE, 2005). In the two institutions interviews with researchers and curators, behavior observation and questionnaires from employees, trainees, monitors and the public/visitor of the two museums were performed. Although partially referende the initial hypothesis, the research showed that the public/visitor value appears more natural environments, they experience a greater intensity and in addition to the factors listed in the second case, your perception and definition of paths suffer significant influence of emotional relations established with space. Generally the audience/visitor adapts easily to different demands of contemporary art exhibition in the two museums and the built environment (park/garden and museum) interferes with your reading path during the visit, perceived by the public/visitor condition as a factor that favors the enjoyment of works on different mounts (wayfinding), though often become a factor that hinders the legibility of the building and its built environment

Da promessa à realidade: a cidade potiguar do século XIX, a partir do olhar da elite

The purpose of this research is to apprehend the perception that the ruling elite, especially the Presidents of the province of Rio Grande do Norte/Brazil, had about the potiguar city, that is, the urban localities existing in the province along the 19th century. By interweaving political, administrative, socioeconomic and spatial aspects, the study of this perception involves two distinct moments, which are also linked: a moment of apprehension of the city, that is, how the elite seizes, describes and criticizes the city; and, a second moment, which occurs simultaneously or after the first moment, of intervention in the city, in which the elite exposes its vision and projects for the city and for the territory. Rather than describing the potiguar city in itself, the research is an attempt to reveal how it was perceived along this process from a particular standpoint or discourse, official and elitist, which did not correspond necessarily or completely to what it was in reality. We tried to understand, always through the lens of the discourse, how the ruling elite perceived the potiguar city based on what their members thought about other urban realities, particularly of the advanced countries; how, within an integrated vision, this city was characterized in political, administrative, socioeconomic and spatial terms and how it consolidated itself along the period established for the research. Qualitative and historical in nature, this study was also methodologically developed based upon bibliographical and documental research. Given the fact that this research works with descriptions, comparisons and interpretations, it was necessary to make use of tools such as the discourse analysis in order to apprehend, as much as possible, what lay behind the words of the elite. The primary sources used were essentially the official documents produced by the Presidents of the province, as well as other documents written by top government officials and other members of the administration staff, all of them composing the so-called ruling elite of Rio Grande do Norte. Secondary sources were books and other publications, theses and dissertations, among others. The research made possible the identification of a certain perception of the potiguar city in the 19th century, which is certainly limited because it is grounded on a specific discourse - that of the political and administrative elite, but which, in spite of such a limitation, is still useful to understand the city and its evolution along the period established, among other noteworthy remarks

A forma do privilégio: renda, acessibilidade e densidade em Natal-RN

The aim of this work is to understand the morphological expression of ground occupation by the higher income population, by focusing on population distribution in accordance with income layers and demographical density, as well as topological accessibility (HILLIER and HANSON, 1984) resulting from the urban grid structure. It endeavors to identify a functional organizing principle regarding the intra-urban space of Natal capital city of the state of Rio Grande do Norte, the research focus. In order to achieve this, census data as well as syntactic data were utilized for mapping and spatial analysis of income patterns, topological accessibility and demographical density using Geographical Information System GIS. The organizing principle was named as the Form of Privilege, a pattern that concentrates or tends to concentrate wealth, topological accessibility and low demographical density. Attempting to assess its extent, beyond Natal, this principle was applied to other Brazilian northeastern capitals such as: Fortaleza, CE; Teresina, PI; Aracaju, SE; Recife, PE; and João Pessoa, PB. Findings point out that although the urban structures of these cities are not immune to the Form of Privilege, Natal is emblematic of this phenomenon, a fact that demonstrates the perverse character of its spatial process, which historically creates privileged areas within the city, by means of the appropriation of accessibility as well as of the many urban benesses that are related to it by higher income groups at the expense of the major part of the population, which though being the people mostly in need of the benefits originating from the urban form are excluded from them

Uma cidade para pessoas: funcionalidade, racionalidade e emotividade nas relações mobiliário urbano, espaço público e cidadãos

This research investigates how functionality, rationality, and emotionality applied to urban furniture design contribute to the organization, legibility, and qualification of public spaces, according to different layouts, physical and visual qualities of the urban furniture as well as the quality of urban infrastructure that may influence the uses and appropriation of urban spaces by pedestrians, turning those spaces into socially centripetal or centrifugal places. The work consists of two parts. First refers to a bibliographical review concerning two main issues of the investigation: product design and legibility of public space, defining the conceptual and theoretical bases, linked to methodological strategies aimed at systemic planning and integrated management of urban furniture design and legibility of public spaces (sidewalks), that are necessary to define the existing relationships among the user s interface (pedestrians); product (urban artifacts); built environment (sidewalks). The second part refers to the achievement of empirical approach throughout visual analysis of public spaces and the functional and qualitative evaluation of the existing urban furniture in the central neighborhood of Cidade Alta, Natal, RN, according to the theoretical researched concepts and methodological procedures. The results expose the weaknesses and levels of intensity arising from the relations among public space, urban furniture, and users, revealing the need for theoretical and practical approaches which would help the decision-making in planning, designing and integrating innovative, sustainable, and ethical solutions in order to design attractive public spaces that could provide sociability and citizenship throughout integrated public management, city systemic thinking and urban identity. The suggested guidelines at the end of this research will provide the necessary strategies to design suitable urban furniture systems according to aesthetic and practical urban infrastructure and city context, aiming to ease visual and physical conflicts that may negatively interfere with the appropriation of public spaces by the citizens

Bioprospecção de polissacarídeos sulfatados de macroalgas marinhas do litoral do Rio Grande do Norte: caracterização de uma heterofucana extraída da alga marron sargassum filipendula que induz apoptose em células hela

The coast of Rio Grande do Norte has more than 100 species of seaweed, mostly unexplored regarding their pharmacological potential. The sulfated polysaccharides (PS) are by far the more seaweed compounds studied, these present a range of biological properties, such as anticoagulant activity, anti-inflammatory, antitumor and antioxidant properties. In this study, we extract sulfated polysaccharide rich-extracts of eleven algae from the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum filipendula; Spatoglossum schröederi; Gracilaria caudata; Caulerpa cupresoides; Caulerpa prolifera; Caulerpa sertularioides e Codim isthmocladum), and these were evaluated for the potential anticoagulant, antioxidant and antiproliferative. All polysaccharide extracts showed activity for anticoagulant, antioxidant and/or antiproliferative activity, especially D. delicatula and S. filipendula, which showed the most prominent pharmacological potential, thereby being chosen to have their sulfated polysaccharides extracted. By fractionating method were obtained six fractions rich in sulfated polysaccharides to the algae D. delicatula (DD-0,5V, DD-0, 7V, DD-1,0v, DD-1,3v, DD-1,5v and DD-2,0) and five fractions to the alga S. filipendula (SF-0,5V, SF-0,7V, SF-1,0v, SF-1,5v and SF-2,0v). For the anticoagulant assay only the fractions of D. delicatula showed activity, with emphasis on DD-1, 5v that presented the most prominent activity, with APTT ratio similar to clexane® at 0.1 mg/mL. When evaluated the antioxidant potential, all fractions showed potential in all tests (total antioxidant capacity, hydroxyl and superoxide radicals scavenging, ferrous chelation and reducing power), however, the ability to chelate iron ions appears as the main mechanism antioxidant of sulfated polysaccharides from seaweed. In antiproliferative assay, all heterofucanas showed dose-dependent activity for the inhibition of cell proliferation of HeLa, however, with the exception of SF-0,7V, SF- 1,0v and SF-1,5v, all fractions showed antiproliferative activity against MC3T3, a normal cell line. The heterofucana SF-1,5V had its antiproliferative mechanism of action evaluated. This heterofucan induces apoptosis in HeLa cells by a pathway caspase independent, promoting the release of apoptosis Inducing Factor (AIF) in the cytosol, which in turn induces chromatin condensation and DNA fragmentation into 50Kb fragments. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer.

Aspectos estruturais, farmacológicos e biológicos de fucanas da alga marrom sargassum vulgare

The present study examines the chemical composition and their effects on free radicals, inflammation, angiogenesis, coagulation, VEGF effects and cellular proliferation of a polysaccharides from alga Sargassum vulgare. The sulfated polysaccharide was extracted from brown seaweed by proteolysis with enzymes maxataze. The presence of proteins and sugars were observed in crude polysaccharides. Fractionation of this crude extract was made with growing concentration of acetone (0.3-1.5 v) and produced four groups of polysaccharides. Anionic polysaccharides from brown seaweed Sargassum vulgare, SV1and PSV1 were fractionated (SV1) and purified (PSV1), and displayed with high total sugars and sulfate content and very low level of protein. This fucan SV1 contains low levels of protein and high carbohydrate and sulfate content. This polysaccharides prolonged activated partial thromboplastin time (aPTT) at 50 μg (>240 s). SV1 was found to have no effect on prothrombin time (PT), corresponding to the extrinsic pathway of coagulation. SV1 exhibits high antithrombotic action in vivo, with a concentration ten times higher than heparin. Polysaccharides from S. vulgare promoted direct inhibition enzymatic activity of thrombin and stimulated enzymatic activity of FXa. SV1 showed optimal inhibitory activity of thrombin (50.2±0.28%) at a concentration of 25 μg/mL. Its antioxidant action on scavenging radicals by DPPH was (22%), indicating the polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different erythrocyte groups and displays strong anti-inflammatory action on all concentrations tested in the carrageenan-induced paw edema model, demonstrated by reduced edema and cellular infiltration. Angiogenesis is a dynamic process of proliferation and differentiation. It requires endothelial proliferation, migration, and tube formation. In this context, endothelial cells are a preferred target for several studies and therapies. The antiangiogenic efficacy of polysaccharides was examined in vivo in the chick chorioallantoic membrane (CAM) model by using fertilized eggs. Decreases in the density of the capillaries were assessed and scored. The results showed that SV1 and PSV1 have an inhibitory effect on angiogenesis. These results were also confirmed by inhibition tubulogenesis in rabbit aorta endothelial cell (RAEC) in matrigel. These compounds were assessed in Apoptosis assay (Annexin V - FITC / PI) and cell viability by MTT assay of RAEC. These polysaccharides do not affect the viability and do not have apoptotic or necrotic action. RAEC cell when incubated with SV1 and PSV1showed inhibition of VEGF secretion, observed when compounds were incubated at 25, 50 and 100 μg/μL. The VEGF secretion with the RAEC cell line for 24 h, was more effective for PSV1 at 50 μg/μL(71.4%) than SV1 100 μg/μL (75.9%). SV1 and PSV1 had an antiproliferative action (47%) against tumor cell line HeLa. Our results indicate that these sulfated polysaccharides have antiangiogenic and antitumoral actions