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Carreadores lipídicos nanoestruturados para incorporação de complexos de cobre(ii) aplicáveis no estudo frente ao Mycobacterium tuberculosis / Nanostrutured lipid carriers to incorporation for copper(ii) complex applicable in the study against Mycobacterium tuberculosisSato, Mariana Rillo [UNESP] 03 February 2016 (has links)
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Previous issue date: 2016-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Tuberculosis (TB) is known worldwide as the leading infectious disease of chronic evolution in which the abandonment of treatment before the recommended period tends to cause the development of more severe disease, such as the appearance of resistant strains. Copper interacts with biologically active ligands developing copper(II) complex with activities antimicrobial. Nanostructured lipid carriers (NLCs) have gained prominence in the pharmaceutical field, since they have the ability to compartmentalize efficiently lipophilic drugs and modify their properties and behavior in the biological environment. The aims of this study was to evaluate the potential of copper(II) complexes-loaded NLCs applicable in the study against Mycobacterium tuberculosis. Copper(II) complexes containing isoniazid binder were obtained and they were entitled C1, C2, and C3 where they have co-binders anionic chloride, cyanate and thiocyanate, respectively. NLCs were obtained by fusion-emulsification technique, formulations were obtained by Ultra turrax at 5000 rpm for 10 minutes followed by sonicator at 8% amplitude for 20 minutes to obtain stable NLCs, those were incorporated of 3.50% and 0.50% to surfactant poloxamer 407 and cetrimonium bromide, respectively, and 2.07%, 2.50% and 0.88% of polyoxyethylene stearate lipids, triglycerides of capric acid/caprylic and ethoxylated hydrogenated castor oil 40 OE (F32) or castor oil (F38), respectively. Copper(II) complexes were incorporated into NLCs (F32.OE.C1, F32.OE.C2, F32.OE.C3 and F38.OR.C1, F38.OR.C2, F38.OR.C3) and characterized by diameter (Dmn) , polydispersivity index (PDI) and zeta potential (ZP) for 1, 15, 30, 45 and 60 days, which revealed homogeneous dispersion and excellent physical stability over the same period; the atomic force microscopy confirmed that developed NLCs are spherical particles dispersions at nanometer scales; differential scanning calorimetry revealed that the constituents used in the formulations interacted in the systems and confirmed that copper(II) complexes were incorporated in the NLCs. The antimicrobial activity of the complexes against M. tuberculosis H37Rv was determined by the resazurin microdilution assay demonstrated potential anti-TB when complexes were incorporated into NLCs. Cytotoxicity assay in murine macrophage-like cells J774A.1 (ATCC TIB-67) e MRC-5 (ATCC-CCL-171) for 24 h and acute toxicity of the complex against Artemia salina L (Artemiidae) showed the formulations have toxicity in all tested concentrations; although published reports indicated the safety of the components used of the formulations, studies should be conducted in animal models to assess the acute toxicity. These results suggest that NLCs have potential application in the study against Mycobacterium tuberculosis. / A Tuberculose (TB) é mundialmente conhecida como a principal doença infecto-contagiosa de evolução crônica, em que o abandono do tratamento antes do período recomendado tende a ocasionar o desenvolvimento de casos mais graves da doença, gerando o aparecimento de cepas resistentes. O cobre interage com ligantes biologicamente ativos desenvolvendo complexos de cobre(II) com ações antimicrobiana. Carreadores lipídicos nanoestruturados (CLNs) vêm se destacando na área farmacêutica, pois apresentam a capacidade de compartimentalizar, de maneira eficiente fármacos lipofílicos e de modificar suas propriedades e comportamento em meio biológico. O objetivo deste trabalho foi avaliar o potencial de CLNs acrescidos de complexos de cobre(II) aplicáveis no estudo frente ao Mycobacterium tuberculosis. Foram obtidos 3 complexos de cobre(II), intitulados C1, C2 e C3 que contem o ligante isoniazida e os co-ligantes aniônicos cloreto, tiocianato e cianato, respectivamente. Os CLNs foram obtidos pela técnica de fusão-emulsificação, testando-se diversas formulações por Ultra turrax a 5000 rpm por 10 minutos e por sonicador com amplitude 8% por 20 minutos até a obtenção de CLNs estáveis, que foram constituídos de 3,50% e 0,50 % de poloxamer 407 e brometo de cetrimônio, respectivamente, e de 2,07%, 2,50% e 0,88% de estearato de polioxietileno, triglicérides do ácido cáprico/caprílico e óleo de rícino hidrogenado e etoxilado 40 (F32) ou óleo de rícino (F38), respectivamente. Os complexos de cobre(II) foram incorporados nos CLNs (F32.OE.C1, F32.OE.C2, F32.OE.C3, e F38.OR.C1, F38.OR.C2, F38.OR.C3), e caracterizados por diâmetro hidrodinâmico médio (Dnm), índice de polidispersidade (IPD) e potencial zeta (PZ) por 1, 15, 30, 45 e 60 dias, revelando homogeneidade da dispersão e excelente estabilidade física; a microscopia de força atômica confirmou que os CLNs tratam-se de dispersões de partículas esféricas em escalas nanométricas; a calorimetria exploratória diferencial revelou que os componentes utilizados nas formulações interagiram para formação do sistema e que os complexos de cobre(II) foram incorporados nos CLNs. A atividade antimicrobiana dos complexos, frente ao M. tuberculosis H37Rv determinada pelo ensaio de microdiluição com Resazurina evidenciaram potencialização da ação anti-TB pela incorporação dos complexos nos CLNs. Os ensaios de citotoxicidade frente à linhagem de macrófagos J774A.1 (ATCC TIB-67) e de MRC-5 (ATCC-CCL-171) em 24 h e a toxicidade aguda dos complexos frente à Artemia salina L., mostraram que as formulações apresentaram toxicidade em todas as concentrações testadas; apesar de relatos da literatura indicarem a segurança dos componentes das formulações, estudos devem ser realizados em modelos animais para avaliar a toxicidade aguda. Os resultados sugerem que os CLNs apresentam aplicação potencial no estudo frente ao Mycobacterium tuberculosis.
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Etude des mécanismes physiques de fiabilité sur transistors Trigate/Nanowire / Study of the physical mechanisms affecting the reliability of the trigate transistorsLaurent, Antoine 05 April 2018 (has links)
En continuant à suivre la loi de Moore, les transistors ont atteint des dimensions de plus en plus réduites. Cependant pour les largeurs inférieures à 100nm, des effets parasites dits de canaux courts sont apparus. Il a ainsi fallu développer de nouvelles architectures, à savoir les transistors 3D, aussi appelés trigates, finfets ou encore nanofils. Le remplacement des transistors planaires utilisés depuis les années 60 par ces dispositifs tridimensionnels constitue une réelle rupture technologique et pose de sérieuses questions quant à la fiabilité de ces nouveaux composants électroniques. Parmi les spécificités des dispositifs 3D, on peut notamment citer l’utilisation de différents plans cristallins du silicium, les potentiels effets d’angle ou encore le confinement des porteurs de charge. Les principaux mécanismes de fiabilité doivent, à ce titre, être étudiés afin de prédire le vieillissement de tels dispositifs. Ainsi, l’évolution du transistor MOS et les limites de l’architecture planaire sont rappelées dans un premier temps. Les différents mécanismes de dégradation ainsi que les méthodes de caractérisation sont également exposés. Les défauts d’oxyde jouant un rôle important en fiabilité, l’impact sur la tension de seuil VT d’une charge élémentaire q selon sa localisation spatiale a été simulé. On a ainsi pu constater que l’influence de ces défauts change selon leur position mais aussi selon les dimensions du transistor lui-même. Par la suite, le manuscrit se concentre sur la dégradation BTI (Bias Temperature Instabilities). Une comparaison entre les transistors trigates et d’autres quasi planaires a ainsi été effectuée en mettant en évidence les effets de la largeur du MOSFET. Un autre mécanisme important de fiabilité est intitulé dégradation par porteurs chauds ou HC, hot carriers en anglais. Les principaux modèles développés sur les architectures planaires ont été rappelés puis vérifiés pour les transistors 3D. Lors de stress HC, les niveaux de courant sont tels que des effets d’auto-échauffement apparaissent et dégradent les paramètres électriques du dispositif. Cette contribution a alors dû être décorrélée de la contrainte porteurs chauds afin d’obtenir uniquement la dégradation HC. De manière similaire au BTI, les effets de la largeur du transistor ont également été analysés pour ce mécanisme de fiabilité. Enfin, l’effet des contraintes mécaniques dans le canal, telles que le strained-SOI ou l’apport de germanium, a été étudié non seulement du point de vue des performances mais également de la fiabilité. Nous avons alors pu en déduire le meilleur compromis performance/fiabilité réalisable. / By continuing to follow Moore’s law, transistors have reached ever smaller dimensions. However, from 100nm gate length, parasitic effects called short channel effects appear. As a result new architectures named trigate, nanowires or finfets have been developed. The transition from planar technology used for the last fifty years to 3D devices is a major technological breakthrough. The special features of these architectures like conduction over various crystalline planes, corner effects or carrier confinement effects raise numerous questions about their reliability. Main reliability mechanisms have to be study in order to evaluate 3D transistor aging. In this way, MOS transistor evolution and planar architecture limits have first been reminded. The electrical degradation mechanisms and their characterization methods have also been exposed. As oxide defects represent an important part of device reliability, impact on threshold voltage VT of an elementary charge q has been simulated in accordance to its spatial localization. Thus we can notice that the defect influence on VT change with at once its position and the device dimensions. Next, this manuscript focuses on Bias Temperature Instabilities (BTI). A parallel has been done between narrow Trigate devices and wide ones which can be considered as planar transistors and a width effect on NBTI (Negative BTI) degradation has been highlighted. Another major reliability mechanism is called hot carrier degradation. Its principle models developed on planar architecture have been remembered and their validity on Trigate transistors has been verified. During HC stress, current density can be so high that self-heating effects appear and degrade device electrical parameters. Therefore this contribution has been decorrelate from HC degradation in order to obtain the result of HC stress only. As in BTI chapter, width effect has also been evaluated for this reliability mechanism. Finally strain effects in channel region have been analyzed from both performance and reliability point of view. As a conclusion the best tradeoff between these two items has been determined.
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Salivary gland transcriptome of Rhipicephalus (Boophilus) microplusGenu, Siyamcela 11 1900 (has links)
The cattle tick, Rhipicephalus (Boophilus) microplus is a tick of veterinary and health importance globally, transmitting Babesia bovis and B. bigemina. Tick control is important and needed to prevent livestock diseases caused by tick-transmitted pathogens. Traditionally, tick control methods have resulted in development of
acaricide-resistant ticks, environmental pollution and meat and milk contamination. Therefore, there is a need for alternative method and vaccines directed against tick feeding. The aim of this study was to identify proteins involved in tick feeding, tickhost-pathogen interactions and tick reproduction. Consequently, these will help in identification of antigens with the ultimate goal of developing anti-tick vaccines. R. (B.)
microplus female ticks were collected at five different feeding stages. RNA was isolated from the salivary gland extracts (SGEs). The cDNA libraries were synthesized and sequenced with the Illumina MiSeq technology. Transcriptome data was analyzed with CLC Genomics Workbench, Trinity and Minia. The SGEs were also used to
isolate the fractions: membrane, soluble and pellet protein for proteomic analysis. The proteomics data was analysed with Mascot, X!Tandem and Scaffold. Both the transcriptome and proteome analysis revealed the presence of major secretory protein families such as Kunitz, lipocalins, serpins, cement proteins and metalloproteases, while the majority of transcripts coded for housekeeping genes. / National Research Foundation (South Africa) / Life and Consumer Science / M. Sc. (Life Science)
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Passenger Volumes Post-accession to the European Union: Signs of Southwest Airlines' Model in Central and Eastern EuropeJanuary 2012 (has links)
abstract: In 2004 the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, and Slovenia joined the European Union (EU) as part of the EU's greatest enlargement to date. These countries were followed by Bulgaria and Romania in 2007. One benefit of joining the EU was the freedom for residents in the new EU member states to migrate to western European nations, notably the United Kingdom (UK). A result of this new freedom was an increased need for air travel. The intersection of the expansion of the EU with the introduction of low-cost airline service was the topic addressed in this study. Yearly traffic statistics obtained from the UK Civil Aviation Authority were used to formulate a trend line of passenger volume growth from 1990 to 2003. Through a time series regression analysis, a confidence interval was calculated that established that, beginning with the year 2004, passenger volumes exceeded the probable margin of error, despite flat population growth. Low-cost carriers responded to these market conditions through the introduction of new flights across the region. These carriers modeled themselves after Southwest Airlines, a strategy that appeared to be more effective at meeting the needs of the post-accession travel boom. The result was a dramatic rise in both passenger volumes and low-cost airline routes in an east-west direction across the continent. / Dissertation/Thesis / M.S.Tech Technology 2012
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Portadores quentes: modelo brownianoBauke, Francisco Conti [UNESP] 17 February 2011 (has links) (PDF)
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bauke_fc_me_rcla.pdf: 1413465 bytes, checksum: 5695187aaf8a438767e3a8684e26c073 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Neste trabalho estudamos o modelo do movimento Browniano de uma partícula carregada sob a ação de campos elétrico e magnético, externos e homogêneos, no formalismo de Langevin. Calculamos a energia cinética média através do teorema da flutuação-dissipação e obtivemos uma expressão para a temperatura efetiva das partículas Brownianas em função da temperatura do reservatório e dos campos externos. Esta temperatura efetiva mostrou-se sempre maior que a temperatura do reservatório, o que explica a expressão “portadores quentes”. Estudamos essa temperatura efetiva no regime assintótico, ou seja, no estado estacionário atingido em tempos muito longos (quando comparado com o tempo de colisão) e a utilizamos para escrever as equações de transporte em semicondutores, denominadas equações de Shockley generalizadas sendo que incluem nesse caso também a ação do campo magnético. Uma aplicação direta e relevante foi a modelagem para o já conhecido efeito Gunn para portadores assumidos como Brownianos. A temperatura efetiva calculada por nós no regime transiente permitiu estudar também os efeitos do reservatório na relaxação da temperatura efetiva à temperatura terminal (de não equilíbrio e estacionária). Nossos resultados no que diz respeito ao efeito Gunn, embora seja o modelo mais simples de um portador Browniano, mostrou uma surpreendente concordância com resultados experimentais, sugerindo que modelos mais sofisticados devam incluir os elementos apresentados neste estudo / We present a Brownian model for a charged particle in a field of forces, in particular, electric and magnetic external homogeneous fields, within the Langevin formalism. We compute the average kinetic energy via the fluctuation dissipation and obtain an expression for the Brownian particle´s effective temperature. The latter is a function of the heat bath temperature and both external fields. This effective temperature is always greater than the heat bath temperature, therefore the expression “hot carriers”. This effective temperature, in the asymptotic regime, the stationary state at long times (greater than the collision time), is used to write down the transport equations for semiconductors, namely the generalized Shockley equations, now incorporating the magnetic field effect. A direct and relevant application follows: a model for the well known Gunn effect, assuming a Brownian scheme. In the transient regime the computed effective temperature also allow us to probe some features of the heat bath, as the effective temperature relaxes to its terminal stationary value. As for our results in the Gunn effect model, the simplest of all in a Brownian scheme, we obtain a surprisingly good agreement with experimental data, suggesting that more involved models should include our minimal assumptions
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A Letter in the Mail : A Grounded Theory Based Exploration of the Health of Swedish Postal CarriersKull, Andreas January 2018 (has links)
Andreas Thomas Kull. A Letter in the Mail – A Grounded Theory Based Exploration of the Health of Swedish Postal Carriers. Master thesis in Occupational Health Sciences, 30 credits. University of Gävle. Introduction: Postal Carriers in Sweden is an occupational group with a distinct work environment controlled by third parties. One third of all postal carriers in Sweden experience musculoskeletal issues. Little to no research has looked in to postal carriers experience of how their work is affecting their health. This study aims to explore why and how postal carriers are experiencing their current health states. Method: This Grounded Theory Method based study gathered data from both interviews and observations. Respondents consisted of seven men and two women. Observations were conducted for three days and consisted of gathering step counts and route information of three different postal carrier routes. Analysation of each interview happened before a new interview took place. Transcribed verbatims were line by line coded. Clusters and codes formed were constantly analysed throughout the data gathering process to ensure emerging theoretical model fit data. Results: Attitude was regarded as the main concern on this study. By being able to moderate contextual and situational factors, i.e. leadership, value towards work, intensity, frequency etc, attitude provided a tool for why individuals experienced postal carrier work in a broad spectrum. Conclusion: Attitude could provide important information of why health states are differing between individuals performing the same type of work.
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Exploring a Web of Carriers Promoting the Travel of an Idea : the Case of a Circular Fashion SystemRudberg, Isabel, Ottow, Frida January 2018 (has links)
In previous research, attention is given to the travel and translation of ideas in order to capture how ideas flow and by whom. External actors, so called carriers, promote certain ideas and discard others, further playing a significant part in the institutionalization of ideas. The multitude of different carriers, their different promotion techniques and interconnectedness call for the need to study them in relation and differentiation to one another. Through a qualitative content analysis of documents, interviews and videos, we present a case study on carriers promoting the current idea of a circular fashion system. The investigated carriers are consultants, media, academia, NGO/NPOs and gurus. Alongside the previously identified sequential and parallel modes of translation, we find carriers promoting the travel of an idea jointly. Among the carriers studied, the findings reveal evidence of (1) linkages through cross-referencing, and (2) collaboration through funding, assignment and co-writing. Coupling the notion of blurred boundaries between carriers with ecologies of translation, the study finds carriers situating in different contexts and constellations, forming hybrids and hierarchies. Providing such evidence of a more complex scenery, we argue that the landscape in which carriers promote an idea is best understood as constituting webs.
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Significados da prática do turismo para portadores de esclerose múltipla em seu tempo de lazerSantini, Heloisa 07 July 2006 (has links)
Os objetivos deste estudo foram investigar os significados das práticas do turismo por sujeitos portadores de esclerose múltipla (EM) em seu tempo de lazer, desvelando as reais condições desses portadores de EM, quanto à efetiva prática de lazer diante das possibilidades e limites desse sujeito. Nesse sentido, foi realizada uma revisão teórica e a dissertação foi dividida em capítulos que tratam da dialética do corpo na modernidade e o lazer, a realidade social dos sujeitos portadores de EM, os significados do lazer para sujeitos portadores de EM. Foi realizado um estudo preliminar exploratório ao tema e, a partir de uma amostra por tipicidade, o processo investigatório compreendeu movimentos reflexivos e críticos. As categorias de análise: lazer, turismo e qualidade de vida foram ressignificadas a partir do referencial proposto, reconstruindo a realidade vivenciada pelos sujeitos portadores de EM, por meio de estudo do comportamento manifesto em seu tempo de lazer. O estudo revelou que as práticas de lazer e de turismo significaram atividades prazerosas e condição de normalidade para ser e estar-no-mundo. / The purposes of this paper were to investigate the meanings of practices of tourism for people with Multiple Sclerosis (MS) in their leisure time, revealing the real conditions of them as in the effective practice of leisure facing the possibilities and limits of the subject. That way, it was done a theory review and the essay was divided in chapters that deal with the dialectic of the body in the modern times and the leisure itself, the social reality of the MS people, and the meanings of leisure for those people. It was done a preliminary exploratory study of the theme and, from a sample by type; the investigatory process has enclosed reflexive and critical movements. The categories of analyzes: leisure, tourism and quality were remeant from the proposed referential, rebuilding the living reality of the people with MS by a study of behavior in their time of leisure. The paper has revealed that practices of leisure and tourism have meant pleasure activities and conditions of normality to be and to be in the world.
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DESENVOLVIMENTO, CARACTERIZAÇÃO, ESTUDOS DE ESTABILIDADE, GENOTOXICIDADE, CITOTOXICIDADE E ECOTOXICIDADE DE SISTEMAS NANOESTRUTURADOS CONTENDO ÓLEO ESSENCIAL DE GENGIBRE OU TRANS-ANETOLPinto, Cláudia Grigolo 27 March 2018 (has links)
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Previous issue date: 2018-03-27 / This study explored the profile of the ginger essential oil and of the trans-anethole,
which are medicinal plants active ingredients extensively used in traditional medicine. These
have been popularized in recent years, due to several properties, which are, however,
significantly toxic. These ingredients were manipulated by methods used in nanotechnology.
Thus, lipid- and polymer-based nanostructure systems, such as nanocapsules, nanoemulsions,
and lipid carriers were produced. For the polymer systems, a preliminary study was carried out
in order to determine which polymer would be used, which was later tested using a polymer
swelling test. After the definition of the polymer and of the best methodology, the systems were
produced. These had their physical-chemical parameters, such as polydispersity index, zeta
potential, mean particle diameter, pH and stability evaluated for 90 days to verify in which
conditions they were stable, thus allowing the determination of the best storage conditions.
Nanocapsules, nanoemulsions, and lipid carriers containing ginger essential oil were produced.
Similarly, systems which contained trans-anethole were produced. For comparison purposes,
blank systems, which do not have the studied ingredients, were also produced. After
characterization and stability studies, each of the systems was analyzed for the following:
cytotoxicity and cell viability in macrophages by the MTT assay, genotoxicity by the Comet
assay, antimicrobial activity by disk diffusion, antimicrobial activity by broth microdilution,
and ecotoxicity by bioassay with Artemia. As for the antimicrobial activity, only some of the
formulations presented significant activity on the analyzed strains. In general, the results
obtained indicated a reduction in the cyto-, geno- and the eco-toxicity of the nanostructured
systems when compared with the free forms of the studied ingredients and their respective
controls. This study made it possible to corroborate other studies which have also demonstrated
the great potential of the use of nanotechnology to explore the profile of medicinal plants.
Through these methodologies, their toxicity could be reduced and pharmacological and
environmental safety could be promoted. Considering the results obtained, four scientific
articles were produced and submitted to scientific journals. / O óleo essencial de gengibre e o trans-anetol, que são ativos oriundos de plantas
medicinais com extensa utilização na medicina tradicional os quais tiveram sua popularização
nos últimos anos, sendo relacionados a várias propriedades, que, no entanto, apresentam
toxicidade bastante significativa. Através de métodos empregados na Nanotecnologia foram
produzidos sistemas nanoestruturados poliméricos e de base lipídica, no caso, nanocápsulas,
nanoemulsões e carreadores lipídicos. Para os sistemas poliméricos, foi realizado um estudo
preliminar para a escolha do polímero que seria utilizado. Este estudo empregou o teste do
inchamento do polímero. Após a definição do polímero e da melhor metodologia, os sistemas
foram produzidos e tiveram seus parâmetros físico-químicos, como índice de polidisperssão,
potencial zeta, diâmetro médio de partículas, pH e a estabilidade avaliados por 90 dias para
verificar em que condições permaneciam estáveis, possibilitando determinar as melhores
condições de armazenamento. Foram produzidas nanocápsulas, nanoemulsões e carreadores
lipídicos contendo óleo essencial de gengibre e as mesmas categorias de sistemas contendo
trans-anetol. Para fins de comparação, também foram produzidos sistemas brancos, ou seja,
nanocápsulas, nanoemulsões e carreadores lipídicos sem os ativos de estudo. Após os estudos
de caracterização e de estabilidade, cada um dos sistemas foi analisado em relação às seguintes
atividades: citotoxicidade e viabilidade celular pelo ensaio MTT, genotoxicidade pelo ensaio
Cometa, atividade antimicrobiana por disco-difusão, atividade antimicrobiana por
microdiluição em caldo e atividade ecotóxica por bioensaio com artêmias. Quanto à atividade
antimicrobiana, apenas os tratamentos com óleo de gengibre livre apresentaram atividade
significativa sobre as cepas de E. coli, P. aeruginosa, S. aureus e C. albicans. Os resultados
obtidos, conforme objetivo proposto apontaram redução da cito, geno e ecotoxicidade dos
sistemas nanoestruturados testados quando comparados com as formas livres dos ativos
estudados e com seus respectivos controles, o que tornou possível corroborar com outros
estudos que também demonstram o grande potencial do uso de Nanotecnologia para explorar o
perfil de ativos oriundos de plantas medicinais, que, mediante essas metodologias, reduzem a
toxicidade, promovendo a segurança farmacológica e ambiental para a utilização dos mesmos.
Diante dos resultados obtidos, quatro artigos científicos foram produzidos e submetidos a
revistas científicas para divulgação.
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Estudos sobre a competencia vetorial de populações de mosquitos (Diptera, Culiciade) da região metropolitana do Recife, Pernambuco e de Campinas, São Paulo, Brasil, para Dirofilaria immitis (Nematoda, Onchocercidae) / Vectorial competence studies of mosquitoes populations (Diptera, Culiciade) of Metropolitan Region of Recife, Pernambuco and Campinas, São Paulo, Brazil to Dirofilaria immitis (Nematoda, Onchocercidae)Silva, Gilcia Aparecida de Carvalho 24 January 2006 (has links)
Orientador: Carlos Fernando Salgueirosa de Andrade / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T12:43:31Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: Mosquitos pertencentes aos gêneros Culex, Aedes, Anopheles, Mansonia, Psorophora e Coquillettidia são susceptíveis à infecção por Dirofilaria immitis (Leidy, 1856), podendo transmitir o filarídeo aos cães e gatos. Os vetores de D. immitis no Brasil são conhecidos apenas nos Estados do Rio de Janeiro e do Maranhão, fazendo-se necessária a investigação da susceptibilidade e da competência vetorial de espécies existentes nos demais Estados brasileiros. O presente trabalho teve por finalidade verificar a freqüência de infecção por D. immitis em cães domiciliados na Região Metropolitana do Recife, bem como avaliar a susceptibilidade e a competência vetorial de Culex quinquefasciatus Say, 1823, Aedes aegypti Linnaeus, 1762 e Ae. albopictus Skuse, 1894 provenientes de área endêmica e não endêmica para a transmissão desse filarídeo, em condições experimentais. A resposta imune humoral (melanização) apresentada pelos mosquitos expostos à infecção também foi avaliada. Para a realização do inquérito epidemiológico, 816 amostras de sangue canino foram coletadas nas áreas costeiras da Região Metropolitana do Recife e no município de Bezerros, agreste do Estado de Pernambuco. As amostras sangüíneas foram analisadas por meio de teste parasitológico para a pesquisa de microfilárias de D. immitis, utilizando-se o método modificado de Knott. Para a avaliação da competência vetorial Cx. Quinquefasciatus população RECIFE, Ae. aegypti populações RECIFE, UNICAMP e linhagem ROCKFELLER e Ae. albopictus população RECIFE foram criados em insetário sob condições controladas (28 '+ ou ¿' '1 GRAU C¿ e 80 ' + ou ¿' 5% de umidade relativa do ar). As fêmeas das espécies estudadas foram alimentadas com sangue canino contendo diferentes densidades de microfilárias de D. immitis, por meio de membrana artificial confeccionada com pele fresca de animal. Para Cx. quinquefasciatus, que é uma espécie ornitofílica, foi utilizada pele de codorna, e para Ae. aegypti e Ae. albopictus a membrana artificial foi confeccionada com pele de rato. Os resultados obtidos no estudo mostraram freqüência de 3,61%, 7,89% e 7,69% de cães infectados na Ilha de Itamaracá, Igarassu e Recife, respectivamente. Após as infecções experimentais, observou-se que a mortalidade de Cx. quinquefasciatus não foi influenciada pela exposição a diferentes densidades de microfilárias de D. immitis (F = 0,0615, p>0,05) e os índices encontrados variaram de 8,9% a 36,25%. Os índices de eficiência vetorial (IEV) apresentados por Cx. quinquefasciatus população RECIFE variaram de 7,8% a 56,5%. Em relação à razão de infecção, o maior índice foi encontrado no grupo de fêmeas expostas a densidade de 1913 microfilárias/ml, entretanto, não foi influenciado pela taxa de ingurgitamento das fêmeas (F=3,2937, p>0,05). Por meio de melanização, Cx. quinquefasciatus população RECIFE, limitou a intensidade do parasitismo, promovendo o equilíbrio da relação parasito-hospedeiro e deste modo passando a ser um excelente vetor de D. immitis na Região Metropolitana do Recife. Dentre as espécies de Aedes estudadas, verificou-se que a população RECIFE de Ae. aegypti apresentou maior mortalidade (70,7%) ao final dos experimentos, apresentando diferença estatisticamente significante (p<0,01) em relação à linhagem ROCKFELLER, população UNICAMP e Ae. albopictus população RECIFE, que não diferiram entre si (p>0,05). Em relação ao índice de eficiência vetorial (IEV) foi detectado um índice de 7,4% para a linhagem ROCKFELLER e uma variação de 20,0% a 53,8% para as populações de Ae. aegypti e 25,2% para Ae. albopictus população RECIFE. O maior número de larvas de D. immitis infectantes na probóscide foi apresentado por Ae. albopictus população RECIFE, além de uma baixa mortalidade. Desta forma, esta população mostrou-se susceptível ao filarídeo e por apresentar baixa mortalidade, foi considerada como a melhor vetora. Ae. aegypti população RECIFE não apresentou reação de melanização e apresentou mortalidade acentuada, enquanto que Ae. aegypti população UNICAMP e linhagem ROCKFELLER mostraram-se refratárias à infecção por D. immitis / Abstract: Mosquitoes belong to the genus Culex, Aedes, Anopheles, Mansonia, Psorophora and Coquillettidia are susceptible to infection of Dirofilaria immitis (Leidy, 1856) and some of them serve as vectors heartworm disease in dogs and cats. Although the potential vectors of canine heartworm in Brazil have been recorded only in Rio de Janeiro and Maranhão State and no more date are available. The objective of this study was to verify the frequency of heartworm infection in dogs in metropolitan region of Recife and also identify under experimental conditions their ability of Culex quinquefasciatus Say, 1823, Aedes aegypti Linnaeus, 1762 and Ae. albopictus Skuse,1894 from enzootic and non enzootic areas to become infected with and transmit D. immitis. After the experimental infection of mosquitoes, the melanization response to larvae of D. immitis also was evaluated. The survey study were performed on a total of 816 dogs from costal areas of Metropolitan Region of Recife and Bezerros County, located in agreste area of Pernambuco State. Whole blood samples were collected from all animals and were examined for the presence of microfilariae of D. immitis by the modified Knott test. To verify the vector competence of Cx. quinquefasciatus RECIFE population, Ae. aegypti RECIFE, UNICAMP populations and also ROCKFELLER strain and Ae. albopictus RECIFE population, the mosquitoes were reared under constant insectary conditions (28 '+ or ¿' '1 DEGREE C¿ and 80 '+ or ¿' 5% relative humidity). Females mosquitoes, were exposed to blood¿s dog with diferents density of D. immitis microfilariae by artificial feeding apparatus made by fresh animal skin. For this puporse, ornithophilic Cx. quinquefasciatus was feeding by skin quail menbrane, and for the Ae. aegypti and Ae. albopictus the artificial membrane was made by rat skin. The results of the survey study showed 3.61%, 7.89%, and 7.69% of heartworm infection frequency in dog from Itamaracá Island, Igarassu and the city of Recife respectively. The mortality of Cx. Quinquefasciatus RECIFE population observed in the vector competence study did not show influence of different density of microfilariae of D. immitis (F = 0.0615, p>0.05) and the mortality rate was 8.9% to 36.25%. The vector efficiency (VE) rates of Cx. quinquefasciatus RECIFE population were 7.8% to 56.5%. The higher infection rate was showed in females feeding with blood containing 1913 mf/ml, but no influence was observed in engorged females. The melanization response observed in Cx. quinquefasciatus was important for vector survival by limiting the number of larvae, acting as an important mechanism of parasitic-host interactions. The data indicate that the Cx. quinquefasciatus RECIFE population should is an excelent vector of D. immitis at metropolitan region of Recife. Significant difference (p<0.01) was observed in the mortality rates between the RECIFE population of Ae. aegypti, UNICAMP population, ROCKFELLER strain, and Ae. albopictus RECIFE population. Although no difference were observed between Ae. aegypti ROCKFELLER, UNICAMP and Ae. albopictus RECIFE population. The vector efficiency (VE) rates of Ae. aegypti and Ae. albopictus RECIFE population were 7.4% to 53.8% and 25.2% respectively. Not only the high number of infective third stage larvae of D. immitis in mouth of mosquitoes but also low mortality was observed in Ae. albopictus RECIFE population. This data showed that this specie is the best vector of heartworm infection in the study area. No melanization response was observed in Ae. Aegypti RECIFE population but high mortality was reported. The UNICAMP population and ROCKFELLER strain of Ae. aegypti were refractory to infection to D. immitis / Doutorado / Doutor em Parasitologia
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