Vi möter medietekniken genom förståelsen av en assemblage; att medie/a – teknik inte existerar utan relationen som binder dem samman. Medieteknik skapas på så sätt genom interaktioner och samverkan mellan de termer som utgör området och syftar alltid på en praktik. En assemblage är en kommunikation, en pågående process – aldrig statisk, alltid produktiv. Utgångspunkten och metoden blir således att ingå partnerskap, utifrån assemblages, med och genom den medietekniska praktiken – i syfte att befinna oss i mitten, i kopplingen, i mötet. Det första partnerskapet vi utgår ifrån är den i vår rubrik: TRANS–MISSION. Trans- står för det överskridande, det öppna, det osäkra medan mission- står för riktningen, avgränsningen, uppdraget. Vi utgår inte från vad ett medium är eller representerar utan vad ett medium gör och producerar. Vår undersökning syftar till att utmana dualistiska synsätt på medieteknik, såsom form och innehåll, designer och produkt, teori och praktik. Vi ifrågasätter antropocentriska förhållningssätt till teknik och material, samt tendensen att se mediet som en statisk överföringsprocess. Undersökningen tar sin utgångspunkt i Gilles Deleuzes och Félix Guattaris filosofi och begreppsapparat främst från det omfattande verket, Tusen Platåer (1980). Ett arbete i syfte att skapa en ontologi som inte utgår från en transcendental världsbild, utan istället en värld i konstant tillblivelse genom kopplingar och flöden. I fokus står relationerna snarare än punkter, identiteter eller hållplatser. / We approach media technology through the understanding of an assemblage; that media– technology cannot exist without one another. Consequently, media-technology are created through the interactions between and co-evolution of the terms that create the field. An assemblage is a communication, an ongoing process – never static always productive. The starting point and method are thus to enter into partnerships, based on assemblages, with and through media technology practice - in order to be in the middle, in the connection, in the nexus. The first partnership we use is in our title: TRANS-MISSION. Trans stands for the excess, the open, the uncertain, while mission is the direction, the demarcation, and the assignment. We do not depend on what a medium is or represents but what a medium does and produces. Our research aims to challenge dualistic approaches to media technology, such as form and content, designer and product, theory and practice. We question anthropocentric approaches to technology and materials, as well as the tendency to view the medium as a static transfer process. The study is based on Gilles Deleuze and Félix Guattari's philosophy and conceptual apparatus, mainly derived from their seminal work, A Thousand Plateaus (1980); a work that strives to create an ontology that does not assume a transcendent worldview, but a world in constant becoming through connections and flows. Relations are in focus, rather than points, identities or stops.

Esta tese descreve uma nova abordagem para a síntese de ciclopenta[g]indóis baseada na reação de contração de anel mediada por trinitrato de tálio (TTN) de uma olefina tricíclica, que contém uma unidade indólica. Foi possível encontrar condições reacionais em que o sal de tálio(III) mostrou-se quimiosseletivo, reagindo com a ligação dupla do anel cicloexênico, sem oxidar a ligação C2-C3 do anel indólico. Utilizando-se a reação acima, pôde-se alcançar a primeira síntese diastereosseletiva da (±)-trans-triquentrina A, que é um alcalóide indólico isolado de uma esponja marinha, em 20 etapas e com rendimento global de 2%. A etapa chave foi uma reação de contração de anel mediada por TTN em CH3CN com redução in situ promovida por NaBH4. Nestas condições o anel trans-1,3-dimetilciclopentânico da molécula alvo foi alcançado com excelente diastereosseletividade. Tentativas de hidrogenação assimétrica do (E)-etil-3-(1-benzil-4-etil-1H-indol-7-il)-but-2- enoato utilizando-se catalisadores de irído foram realizadas, visando a síntese da (+)-trans-triquentrina A. / This thesis presents a new approach toward the synthesis of cyclopenta[g]indoles using a ring contraction reaction mediated by thallium trinitrate (TTN) of a tricyclic olefin, bearing an indol unit. We could find reactional conditions where the thallium(III) salt was chemoselective, reacting on the cyclohexenic double bond without formation of C2-C3 indolic oxidation byproducts. Using the reaction above, we could accomplish the first diastereoselective total synthesis of (±)-trans-trikentrin A, which is an indolic alkaloid isolated from a marine sponge, in 20 steps and 2% of global yield. The key-step was a ring contraction reaction mediated by TTN in CH3CN with in situ reduction promoted by NaBH4. Under this condition the trans-1,3- dimethylcyclopentane moiety of the target molecule was achieved with good diastereoselectivity. The asymmetric hydrogenation of (E)-ethyl-3-(1-benzyl-4-ethyl-1H-indole-7-yl)-but-2- enoate was attempted using iridium catalysts were performed, aiming the synthesis of (+)-trans-trikentrin A.

A ingestão de ácidos graxos trans tem sido consistentemente mostrada ter efeitos adversos nos lipídeos sanguíneos, principalmente na razão LDL:HDL colesterol, que é um forte marcador de risco cardiovascular. De acordo com a Resolução RDC (Resolução da Diretoria Colegiada) de número 360 da ANVISA, de 23 de dezembro de 2003 da ANVISA, (Agência Nacional de Vigilância Sanitária), após 1 de agosto de 2006 as indústrias de alimentos devem declarar o conteúdo de ácidos graxos trans por porção do produto. O objetivo deste trabalho foi analisar a composição de ácidos graxos trans em margarinas e cremes vegetais após a nova legislação. As margarinas e cremes vegetais foram adquiridos na cidade de São Paulo, perfazendo um total de 40 amostras, 17 margarinas cremosas, 8 margarinas light, 1 margarina culinária cremosa, 2 margarinas culinária duras, 1 margarina culinária líquida, 2 alimentos a base de margarina, 8 cremes vegetais e 1 creme vegetal light foram analisados. Os lipídeos foram extraídos por hidrólise ácida, derivatizados com BF3 e em seguida analisados em cromatógrafo gasoso, equipado com coluna capilar SP- 2560 de 100 m a 180C. Os teores de trans totais das margarinas interesterificadas sofreram aumento significativo no período compreendido entre os anos 2000 a 2006, variando de 0 2,17% e 0,71 2,32% respectivamente. Nas margarinas hidrogenadas também foi observado aumento de 11,56 20,55% para 12,63 26,00% em 2006. As margarinas culinárias duras foram o tipo de margarina que apresentou concentrações elevadas de trans, variando de 19,38 a 30,35%. A margarina culinária cremosa e a margarina culinária líquida continham baixos teores de trans, 1,62 e 3,32% respectivamente. Os cremes vegetais interesterificados não sofreram mudança significativa, passando de 0 1,70% para 0 1,66%. No creme vegetal hidrogenado ocorreu redução acentuada dos teores médios de trans totais de 20,55 para 12,63%. A mudança na legislação não foi suficiente para reduzir totalmente os teores de ácidos graxos trans nas margarinas e cremes vegetais. Apesar disto, foi observado um aumento da disponibilidade de margarinas e cremes vegetais zero trans, que são aqueles que contém teores ≤ 0,2 g/porção de 10 g. / Intake of trans fatty acids (TFA) has been consistently shown to have adverse effects on blood lipids, most notably on the LDL:HDL cholesterol ratio, which is a strong marker of cardiovascular risk. According to RDC (Resolução de Diretoria Colegiada) resolution number 360 of the ANVISA (Agência Nacional de Vigilância Sanitária National Agency for Sanitary Vigilance), after August 1, 2006, food industries must declare the trans fatty acid (TFA) content per product serving. The objective of this work was to analyzer the composition of trans fatty acid in margarines and fat spreads after the new legislation. The margarines and fat spread were obtained in the city of São Paulo, making a total of 40 samples, seventeen tub margarines, eight light tub margarines, one culinary tub margarine, two culinary hard margarines, one culinary liquid margarine, two margarine-based foods, eight fat spreads and one light fat spread were analyzed. The lipids were extracted by acid hydrolysis, derivatizados with BF3 and then analyzed by gas chromatograph, equipped with capillary column SP-2560 of 100 m a 180 C. The total TFA content in interesterified margarines significantly increased between 2000 and 2006, rising from 02.17% to 0.712.32%. For hydrogenated margarines, an increase was also observed, from 11.5620.55% to 12.6326.00% by 2006. The culinary hard margarines were the type of margarine that had high concentrations of trans, ranging from 19.38 to 30.35%. Culinary tub margarine and culinary liquid margarine contained low levels of trans, 1.62 and 3.32% respectively. Interesterified fat spreads did not significantly change, from 0 1.70% to 01.66%. In hydrogenated fat spreads, a sharp reduction was seen, with average levels of total trans fats falling from 20.55% to 12.63%. Changes in the legislative regulation were not sufficient to significantly reduce the levels of TFA in margarines and fat spreads. Nevertheless, an increased availability of zero trans fat margarines and fat spreads on the market was observed (levels ≤ 0.2 g per 10 g serving).

No description available.

Os sistemas de gerenciamento de resíduos sólidos urbanos prevêem fases que envolvem desde a sua geração até a disposição final. A atividade de coleta seletiva de materiais previamente segregados é uma parte importante deste gerenciamento. Os custos envolvidos neste tipo de coleta, normalmente mais elevados que os custos da coleta regular, fazem com que esta prática não seja efetuada pela maioria dos municípios brasileiros. Esses municípios tampouco são beneficiados por parcerias privadas, uma vez que o retorno financeiro gerado pela venda do material reciclável geralmente não cobre os custos de coleta, triagem e transporte. A partir deste panorama, este trabalho busca oferecer uma contribuição para o melhor entendimento dos custos envolvidos na operação de coleta destes resíduos. Neste trabalho foram analisados os custos de três sistemas de coleta seletiva de resíduos sólidos domiciliares: por pontos de entrega voluntária (PEVs), porta-a-porta, e um sistema híbrido entre os dois anteriores. A análise levou em conta os custos de transporte, que incluem custos operacionais e custos de capital para cada uma das alternativas. Um SIG-T foi utilizado para determinar a distância percorrida pelos veículos e uma metodologia para a determinação do custo total foi desenvolvida em função da quilometragem percorrida e quantidade de mão-de-obra e equipamentos utilizados. Conclui-se que o melhor método de coleta sempre estará intimamente ligado às características do local em que será implantado. Comparando os três sistemas, observou-se que para a área e para as condições apresentadas neste estudo, o sistema porta-a-porta se mostrou o mais eficaz / Urban solid waste management comprehends phases from its generation to its final disposal. The previously separated materials collection activity is an important part of this management. The costs involved in this type of collection, usually higher than conventional collection costs, make this practice not so used by Brazilian municipalities. These municipalities are neither benefited by private partnerships since the economic feedback from materials sale generally does not cover collection, separation and transport costs. From this point of view, this work seeks for a contribution to the best understanding of the involved costs in the collection operation activity. In this work the costs of three collection systems were studied: by voluntary delivery locations (VDLs), door-to-door, and a hybrid system between the preceding ones. The analysis took for granted the transportation costs to which one of the alternatives, which include operational costs and capital costs. A GIS-Trans had been used to define the traveled distance by the collection vehicles, and a cost determination methodology was developed as function of the traveled distance and the amount of labor and equipments used. It’s concluded that the choice of the best collection method will always be related with implementation area peculiarities. Comparing the three collection systems described above, the door-to-door system is showed to be more efficient for the presented area and conditions assumed for this study

by Kwan Kwok Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 145-155). / Acknowledgment --- p.i / Abstract --- p.ii / List of Tables --- p.vii / List of Figures --- p.x / List of Abbreviations --- p.xii / Chapter Chapter 1 --- Literature review / Chapter 1.1 --- Historical background --- p.1 / Chapter 1.2 --- Chemistry of trans and cis fatty acids --- p.3 / Chapter 1.3 --- Dietary source of trans fatty acids --- p.6 / Chapter 1.4 --- Consumption of trans fatty acids among Western countries --- p.9 / Chapter 1.5 --- Current health concern for excessive intake of trans fatty acids --- p.10 / Chapter 1.6 --- Metabolism of trans fatty acids --- p.13 / Chapter 1.6.1 --- Absorption --- p.15 / Chapter 1.6.2 --- Oxidation --- p.15 / Chapter 1.6.3 --- Incorporation --- p.16 / Chapter 1.6.4 --- Selectivity --- p.17 / Chapter 1.7 --- Impact of trans fatty acids on essential fatty acid metabolism --- p.19 / Chapter 1.8 --- Desaturation and elongation of trans fatty acids --- p.21 / Chapter 1.9 --- Trans fatty acids and neonatal growth --- p.23 / Chapter Chapter 2 --- Amount of trans fatty acids in Hong Kong fast foods / Chapter 2.1 --- Introduction --- p.25 / Chapter 2.2 --- Objective --- p.25 / Chapter 2.3 --- Materials and methods --- p.26 / Chapter 2.4 --- Results --- p.27 / Chapter 2.5 --- Discussion --- p.31 / Chapter Chapter 3 --- Cross-cultural study of trans fatty acids in human milk / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Objective --- p.35 / Chapter 3.3 --- Materials and methods --- p.36 / Chapter 3.4 --- Results / Chapter 3.4.1 --- Dietary information --- p.38 / Chapter 3.4.2 --- Fatty acid composition of Chinese and Canadian human milk --- p.40 / Chapter 3.4.3 --- Difference between Chinese and Canadian human milk --- p.40 / Chapter 3.4.4 --- Difference between Hong Kong and Chongqing Chinese human milk --- p.43 / Chapter 3.4.5 --- The change in milk fat and LCPUFA as lactation progresses --- p.43 / Chapter 3.5 --- Discussion / Chapter 3.5.1 --- Trans fatty acids in human milk --- p.46 / Chapter 3.5.2 --- Content of LCPUFA in human milk --- p.47 / Chapter 3.5.3 --- Content of 18:2n-6 in human milk --- p.48 / Chapter 3.5.4 --- Fat content in Hong Kong and Chongqing Chinese human milk --- p.49 / Chapter 3.6 --- Conclusion --- p.50 / Chapter Chapter 4 --- Trans fatty acids and maternal and neonatal essential fatty acid metabolism / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.2 --- Objectives --- p.53 / Chapter 4.3 --- Materials and methods --- p.53 / Chapter 4.4 --- Results / Chapter 4.4.1 --- Experiment1 / Chapter 4.4.1.1 --- Relationship between the trans fatty acids in maternal diet and those in milk --- p.64 / Chapter 4.4.1.2 --- Relationship between the trans fatty acids in maternal diet and those in neonatal liver --- p.64 / Chapter 4.4.1.3 --- Content of 20:4n-6 in milk and in neonatal liver relative to that in maternal diet --- p.72 / Chapter 4.4.2 --- Experiment2 / Chapter 4.4.2.1 --- Amount of trans fatty acids in rat milk --- p.75 / Chapter 4.4.2.2 --- Trans fatty acids in rat liver phospholipids --- p.75 / Chapter 4.4.2.3 --- Linoleic acid (18:2n-6) content in rat and its relation to maternal diets --- p.86 / Chapter 4.4.2.4 --- Content of 20:4n-6 in rat milk --- p.86 / Chapter 4.4.2.5 --- Content of20:4n-6 in rat liver --- p.89 / Chapter 4.4.2.6 --- Suppression of the synthesis of 20:4t isomers in maternal and neonatal liver --- p.89 / Chapter 4.5 --- Discussion / Chapter 4.5.1 --- Relationship between fatty acid composition of diet and that of milk --- p.93 / Chapter 4.5.2 --- 20:4n-6 in rat milk --- p.95 / Chapter 4.5.3 --- Transfer of trans fatty acids from maternal diet to neonatal liver phospholipids --- p.98 / Chapter 4.5.4 --- The inhibitory effect of trans fatty acids on synthesis of 20:4n-6 in neonatal liver --- p.99 / Chapter 4.5.5 --- Effect of 18:2n-6 supplement on 20:4n-6 level of neonatal liver --- p.101 / Chapter 4.5.6 --- Suppression of 18:2n-6 supplement on synthesis of 20:4t isomers --- p.101 / Chapter 4.6 --- Conclusion --- p.104 / Chapter Chapter 5 --- Accumulation and turnover of trans fatty acids / Chapter 5.1 --- Introduction --- p.105 / Chapter 5.2 --- Objective --- p.105 / Chapter 5.3 --- Materials and methods --- p.106 / Chapter 5.4 --- Results / Chapter 5.4.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.108 / Chapter 5.4.2 --- Selectivity of individual 18:2 trans isomersin liver and adipose tissue --- p.112 / Chapter 5.4.3 --- Turnover of trans fatty acids --- p.112 / Chapter 5.4.4 --- Accumulation and turnover of 18:lt in brain --- p.115 / Chapter 5.5 --- Discussion / Chapter 5.5.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.120 / Chapter 5.5.2 --- Turnover of trans fatty acids --- p.122 / Chapter 5.5.3 --- Accumulation and turnover of trans fatty acidsin brain --- p.124 / Chapter 5.6 --- Conclusion --- p.125 / Chapter Chapter 6 --- In vivo Oxidation of trans fatty acids in rat / Chapter 6.1 --- Introduction --- p.126 / Chapter 6.2 --- Objective --- p.127 / Chapter 6.3 --- Materials and methods --- p.127 / Chapter 6.4 --- Results --- p.129 / Chapter 6.4.1 --- Apparent oxidation of saturated fatty acids --- p.136 / Chapter 6.4.2 --- Apparent oxidation of 18:lt relative to 18:ln-9 --- p.136 / Chapter 6.4.3 --- Oxidation of 18:2t isomers relative to 18:2n-6 --- p.137 / Chapter 6.4.4 --- Effect of 18:2n-6 supplement in PHCO diet on oxidation per se --- p.137 / Chapter 6.5 --- Discussion --- p.138 / Chapter 6.5.1 --- Oxidation of 18:lt and 18:2t isomers --- p.139 / Chapter 6.5.2 --- Effect of 18:2n-6 supplement on oxidation per se --- p.140 / Chapter 6.6 --- Conclusion --- p.141 / General conclusion --- p.142 / References --- p.145

Made available in DSpace on 2014-12-17T15:42:08Z (GMT). No. of bitstreams: 1 FabianoESG_TESE.pdf: 2562039 bytes, checksum: f41fc74bb604ad5b4eb0383a80628c68 (MD5) Previous issue date: 2010-03-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Among the new drugs launched into the market since 1980, up to 30% of them belong to the class of natural products or they have semisynthetic origin. Between 40-70% of the new chemical entities (or lead compounds) possess poor water solubility, which may impair their commercial use. An alternative for administration of poorly water-soluble drugs is their vehiculation into drug delivery systems like micelles, microemulsions, nanoparticles, liposomes, and cyclodextrin systems. In this work, microemulsion-based drug delivery systems were obtained using pharmaceutically acceptable components: a mixture Tween 80 and Span 20 in ratio 3:1 as surfactant, isopropyl mirystate or oleic acid as oil, bidistilled water, and ethanol, in some formulations, as cosurfactants. Self-Microemulsifying Drug Delivery Systems (SMEDDS) were also obtained using propylene glycol or sorbitol as cosurfactant. All formulations were characterized for rheological behavior, droplet size and electrical conductivity. The bioactive natural product trans-dehydrocrotonin, as well some extracts and fractions from Croton cajucara Benth (Euphorbiaceae), Anacardium occidentale L. (Anacardiaceae) e Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae) specimens, were satisfactorily solubilized into microemulsions formulations. Meanwhile, two other natural products from Croton cajucara, trans-crotonin and acetyl aleuritolic acid, showed poor solubility in these formulations. The evaluation of the antioxidant capacity, by DPPH method, of plant extracts loaded into microemulsions evidenced the antioxidant activity of Phyllanthus amarus and Anacardium occidentale extracts. For Phyllanthus amarus extract, the use of microemulsions duplicated its antioxidant efficiency. A hydroalcoholic extract from Croton cajucara incorporated into a SMEDDS formulation showed bacteriostatic activity against colonies of Bacillus cereus and Escherichia coli bacteria. Additionally, Molecular Dynamics simulations were performed using micellar systems, for drug delivery systems, containing sugar-based surfactants, N-dodecylamino-1-deoxylactitol and N-dodecyl-D-lactosylamine. The computational simulations indicated that micellization process for N-dodecylamino-1- deoxylactitol is more favorable than N-dodecyl-D-lactosylamine system. / Dos novos f?rmacos lan?ados no mercado a partir de 1980, cerca de 30% apresentam origem natural ou semissint?tica. Entre 40 e 70% destes novos prot?tipos de f?rmacos (naturais ou sint?ticos) apresentam baixa solubilidade aquosa, o que pode inviabilizar a sua utiliza??o comercial. Uma das alternativas encontrada pela ind?stria farmac?utica foi a veicula??o dessas subst?ncias a partir de ve?culos ou sistemas de libera??o de f?rmacos, tais como: micelas, microemuls?es, lipossomos, nanopart?culas e ciclodextrinas. Neste trabalho, sistemas microemulsionados biologicamente compat?veis foram obtidos utilizando a mistura Tween 80 e Span 20, na propor??o 3:1, como tensoativo, miristato de isopropila ou ?cido ol?ico como fase oleosa, ?gua bidestilada, e em alguns sistemas, etanol como cotensoativo. Tamb?m foram obtidos sistemas auto-microemulsificantes (SMEDDS) utilizando propilenoglicol ou sorbitol como cotensoativo. As microemuls?es obtidas foram caracterizadas quanto ao comportamento reol?gico, tamanho das got?culas e condutividade el?trica. O produto natural bioativo trans-desidrocrotonina (DCTN), bem como extratos e fra??es das esp?cies vegetais Croton cajucara Benth (Euphorbiaceae), Anacardium occidentale L. (Anacardiaceae) e Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae), foram solubilizados satisfatoriamente nos sistemas microemulsionados obtidos, enquanto que outros produtos tamb?m isolados da esp?cie Croton cajucara, trans-crotonina e ?cido acetilaleurit?lico, n?o apresentaram resultados satisfat?rios em termos de solubilidade. A avalia??o da propriedade antioxidante, pelo m?todo do DPPH, dos extratos vegetais incorporados nos sistemas microemulsionados obtidos evidenciou a capacidade antioxidante dos extratos de Phyllanthus amarus e Anacardium occidentale, bem como a atua??o dos sistemas microemulsionados, que para o caso do extrato etan?lico de Phyllanthus amarus dobrou a sua atividade antioxidante quando solubilizado em microemuls?es. O extrato hidroalco?lico de Croton cajucara incorporado em um sistema auto-microemulsificante mostrou atividade bacteriost?tica frente a col?nias de bact?rias Bacillus cereus e Escherichia coli. Adicionalmente, foi realizado um estudo de simula??o computacional por Din?mica Molecular de sistemas micelares para uso farmacol?gico contendo tensoativos derivados de a??cares, N-dodecilamino-1-deoxilactitol e N-dodecil- -lactosilamina, que indicou que o processo de miceliza??o do primeiro sistema ? mais favor?vel que o segundo.

La trypanosomose est la maladie parasitaire la plus dévastatrice en Afrique, et affecte à la fois les hommes et le bétail. Vu l’inefficacité des stratégies de contrôle actuelles, une stratégie alternative dite “anti-maladie” a été proposée dans le cadre de la trypanosomose animale. Elle vise à neutraliser les effets de la maladie plutôt qu’à éliminer le parasite. Une telle stratégie nécessite une meilleure compréhension du développement de la pathologie ainsi qu’une caractérisation détaillée des facteurs de virulence impliqués. Dans ce contexte, nous nous sommes intéressés à l’étude de l’interaction hôte/pathogène entre les trypanosomes Africains et l’endothélium de l’hôte mammifère. En comparant quatre espèces différentes de trypanosomes Africains, nous avons montré que leurs capacités d’activation des cellules endothéliales étaient distinctes. Nous avons clairement démontré que T. congolense, T. vivax et T. b. gambiense activent les cellules endothéliales via la voie de NF-ƘB, alors que T. b. brucei est incapable d’activer cette voie. Cette activation a induit une résponse pro-inflammatoire in vitro et in vivo, ce qui souligne l’importance de ce mécanisme dans le développement de la maladie. Pour la première fois, nous avons identifié une activité sialidase chez le parasite de l’homme T. brucei gambiense, et nous avons démontré que les trans-sialidases trypanosomales sont les médiateurs de cette activation endothéliale et de la réponse inflammatoire consécutive, et ceci à la fois chez les trypanosomes africains d’homme et d’animaux. De plus, nous avons montré que l’activation endothéliale implique l’activité lectin-like des trans-sialidases et non pas l’activité catalytique, ainsi que des récepteurs sialylés sur la surface endothéliale. En conclusion, ce travail a apporté des avancées considérables dans la compréhension de la relation hôte/pathogène et a permis de désigner les sialidases comme un facteur de virulence central dans le dialogue intermoléculaire durant les trypanosomoses, en faisant une cible de choix pour le vaccin « anti-maladie ». / Trypanosomiasis remains by far the most devastating parasitic disease in Africa affecting both humans and livestock. The current control strategies being not efficient, an alternative “anti-disease” strategy aiming to neutralize the pathological effects of the parasite rather than to eliminate it, was proposed. Therefore, it is essential to understand the development of pathogenesis and characterize the involved pathogenic factors. In this context, we wanted to elucidate the host-pathogen interaction between the African trypanosomes and the mammalian host endothelium. By comparing four different trypanosomes species, we showed that they displayed distinct capacities for activation of endothelial cells. We clearly demonstrated that T. congolense, T. vivax and T. b. gambiense activate the endothelial cells via the NF-ƘB pathway, but not T. b. brucei. This activation caused a pro-inflammatory response in vitro and in vivo, showing the importance of this mechanism in the development of pathogenesis. For the first time, we identified sialidase activity in the human parasite T. brucei gambiense, and demonstrated that the trypanosomal trans-sialidases are the mediators of this endothelial activation and its consequent inflammatory response, for both human and animal trypanosomes. Additionnally, we showed that endothelial cell activation is mediated by the lectin-like domain of the trans-sialidase rather than the catalytic site, and involves sialylated receptors of the endothelial cell surface. In conclusion, our study brings considerable insights into the host-pathogen relationship and designates sialidases as a central virulence factor in the molecular crosstalk during trypanosomiasis, which makes it a perfect target for the anti-disease strategy.

Os sistemas de gerenciamento de resíduos sólidos urbanos prevêem fases que envolvem desde a sua geração até a disposição final. A atividade de coleta seletiva de materiais previamente segregados é uma parte importante deste gerenciamento. Os custos envolvidos neste tipo de coleta, normalmente mais elevados que os custos da coleta regular, fazem com que esta prática não seja efetuada pela maioria dos municípios brasileiros. Esses municípios tampouco são beneficiados por parcerias privadas, uma vez que o retorno financeiro gerado pela venda do material reciclável geralmente não cobre os custos de coleta, triagem e transporte. A partir deste panorama, este trabalho busca oferecer uma contribuição para o melhor entendimento dos custos envolvidos na operação de coleta destes resíduos. Neste trabalho foram analisados os custos de três sistemas de coleta seletiva de resíduos sólidos domiciliares: por pontos de entrega voluntária (PEVs), porta-a-porta, e um sistema híbrido entre os dois anteriores. A análise levou em conta os custos de transporte, que incluem custos operacionais e custos de capital para cada uma das alternativas. Um SIG-T foi utilizado para determinar a distância percorrida pelos veículos e uma metodologia para a determinação do custo total foi desenvolvida em função da quilometragem percorrida e quantidade de mão-de-obra e equipamentos utilizados. Conclui-se que o melhor método de coleta sempre estará intimamente ligado às características do local em que será implantado. Comparando os três sistemas, observou-se que para a área e para as condições apresentadas neste estudo, o sistema porta-a-porta se mostrou o mais eficaz / Urban solid waste management comprehends phases from its generation to its final disposal. The previously separated materials collection activity is an important part of this management. The costs involved in this type of collection, usually higher than conventional collection costs, make this practice not so used by Brazilian municipalities. These municipalities are neither benefited by private partnerships since the economic feedback from materials sale generally does not cover collection, separation and transport costs. From this point of view, this work seeks for a contribution to the best understanding of the involved costs in the collection operation activity. In this work the costs of three collection systems were studied: by voluntary delivery locations (VDLs), door-to-door, and a hybrid system between the preceding ones. The analysis took for granted the transportation costs to which one of the alternatives, which include operational costs and capital costs. A GIS-Trans had been used to define the traveled distance by the collection vehicles, and a cost determination methodology was developed as function of the traveled distance and the amount of labor and equipments used. It’s concluded that the choice of the best collection method will always be related with implementation area peculiarities. Comparing the three collection systems described above, the door-to-door system is showed to be more efficient for the presented area and conditions assumed for this study

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