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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

La communication politique en Tunisie de 1987 à 2007. : Les rapports du discours politique, la presse écrite et l'opinion publique / Political communication in Tunisia from 1987 to 2007. : Reports of political discourse, press and public opinion

Najjar, Emna 13 June 2015 (has links)
Cette recherche retrace les aspects manifestes et latents d’une rupture structurelle en Tunisie pendant la gouvernance de l’ancien Président Ben Ali (7 novembre 1987 - 14 janvier 2011), au niveau de la dynamique fonctionnelle entre l’instance politique et médiatique d’un côté et l’instance citoyenne de l’autre. Un soulèvement populaire s’est produit dans le pays entre décembre 2010 et janvier 2011 mettant fin au régime de Ben Ali, causé par nombres de facteurs économiques, sociaux et politiques. Cette rupture est aussi l’un des éléments pouvant expliquer cette révolte. Il a été question, dans ce travail, de démontrer les aspects du dysfonctionnement de la dynamique et les facteurs qui ont déclenché et renforcé un malaise populaire. Nous avons choisi d’aborder ce sujet d’un point de vue discursif, en observant et analysant l’interaction de la parole des trois composantes de l’espace public : la sphère politique, médiatique et citoyenne. Tout au long des deux décennies de Ben Ali, une corrélation non dissimulée s’est installée entre pouvoir politique et médias, dont le but est d’assurer et de maintenir la légitimation du président et de son régime. Dans cette corrélation l’instance citoyenne ainsi que sa parole sont écartées en tant qu’acteur actif participant à la vie politique. Elle est cependant présente comme objet d’autorité et d’instrumentalisation. Le fonctionnement et les réactions de cette instance face à un rôle bien assigné et bien défini de la part de l’alliance politico-médiatique ont été approchés à partir du socle conceptuel de la psychologie sociale. Mots-clés : discours politique, analyse de discours, discours de presse, opinion publique, persuasion, réception, psychologie sociale, Tunisie, Ben Ali. / This thesis traces the self-evident and less obvious aspects of the process that led to the overthrow in Tunisia of th regime of President Ben Ali (November 7th 1987 - 14th 2011); it centers on the dynamics behind the conflict between the media and political apparatus and the civilian population. The uprising between December 2010 and January 2011 ended in the dismantling of Ben Ali's regime, due mainly to economic and political factors. This study highlights the failures that led to popular discontent. We center on a discursive viewpoint, observing and analysing the interaction between three components of the public space: the political, media, and citizen spheres. Throughout Ben Ali's rule of two decades, political power and the media blatantly collaborated so as to maintain the legitimacy of the President and his system. This pact also put aside citizen expression, rendering them mute, as they were reduced to an instrument of those in power. We then studied how they sought emancipation and to alter their limited role via a social psychology approach.
62

AI, LA, ALI e AQUI: gramaticaliza??o de um paradigma emergente no dom?nio funcional da especifica??o nominal

Confessor, Francisco Wildson 25 October 2013 (has links)
Made available in DSpace on 2014-12-17T15:07:19Z (GMT). No. of bitstreams: 1 FranciscoWC_TESE.pdf: 1356357 bytes, checksum: 3457505ffc57c43bafbc9be5a671f327 (MD5) Previous issue date: 2013-10-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the light of the Functional Linguistic Theory, in its North-American version (HOPPER, 1987, 1991, 1998, 2008, 2010; GIV?N, 2001; LEHMANN, 2002; HOPPER; TRAUGOTT, 2003; FURTADO DA CUNHA; OLIVEIRA; MARTELOTTA, 2003, among others), the general objective of this research is to demonstrate, based on morphosyntactic and semantic-pragmatic properties, that AQUI (HERE), A?, ALI and L? (THERE) are part of an emerging paradigm in Brazilian Portuguese recently constituted and still developing of forms indicating specificity in indefinite noun phrases (NP). The data that make up the corpus of this research were collected in the following large Brazilian oral corpora: the Corpus Discurso & Gram?tica: a l?ngua falada e escrita na cidade de Natal (FURTADO DA CUNHA, 1998), the Banco Conversacional de Natal (FURTADO DA CUNHA, 2010), the Projeto Varia??o Lingu?stica no Estado da Para?ba VALPB (HORA, 2005) and the Projeto Varia??o Lingu?stica Urbana na Regi?o Sul do Brasil VARSUL (VANDRESEN, 2002). Firstly, the behavior of the specificity markings AQUI, A?, ALI and L? is described with respect to many factors of morphosyntactic and semantic-pragmatic nature: type of construction in which the markers appeared; existence or not of intervening material between the specificity marker item and the NP s nuclear noun; type of noun to which AQUI, A?, ALI and L? are linked; syntactic function of the specified SN; informational status of the NP to which the specificity markers AQUI, A?, ALI and L? are attached; occurrence of conversational implicatures (GRICE, 1982) in the context of use of these specificity markers. Next, a possible grammaticalization trajectory is outlined, according to which AQUI, A?, ALI and L? would had gone from an early spatial deictic indication to the specificity indication. The results point to the existence of forms with varying degree of emergence in this new paradigm of nominal specification, with A? being, probably, the item most grammaticalized, followed by L?, then ALI and AQUI, which permanence in the paradigm do not yet appear to be consolidated / Este trabalho tem como objetivo geral mostrar, com base em propriedades morfossint?ticas e sem?ntico-pragm?ticas, que AQUI, A?, ALI e L? integram, no portugu?s brasileiro contempor?neo, um paradigma emergente de constitui??o recente e ainda em andamento de formas indicadoras de especificidade em sintagmas nominais indefinidos. Os dados que constituem o corpus desta pesquisa foram coletados em grandes corpora orais brasileiros, a saber: o Corpus Discurso & Gram?tica: a l?ngua falada e escrita na cidade de Natal (FURTADO DA CUNHA, 1998), o Banco Conversacional de Natal (FURTADO DA CUNHA, 2011), o Projeto Varia??o Lingu?stica no Estado da Para?ba VALPB (HORA, 2005) e o Projeto Varia??o Lingu?stica Urbana na Regi?o Sul do Brasil VARSUL (VANDRESEN, 2002). Sob a perspectiva te?rica da Lingu?stica Funcional, em sua vertente norte-americana (HOPPER, 1987, 1991, 1998, 2008, 2010; GIV?N, 2001; LEHMANN, 2002; HOPPER; TRAUGOTT, 2003; FURTADO DA CUNHA; OLIVEIRA; MARTELOTTA, 2003, dentre outros), descreveu-se o comportamento de AQUI, A?, ALI e L? marcadores de especificidade no que diz respeito a fatores de natureza morfossint?tica e sem?ntico-pragm?tica. Os fatores considerados foram os seguintes: tipo de constru??o em que os marcadores apareceram; exist?ncia ou n?o de material interveniente entre o item marcador de especificidade e o nome nuclear do SN; natureza do substantivo ao qual AQUI, A?, ALI e L? se cliticizam; fun??o sint?tica do SN especificado e status informacional do SN adjungido a AQUI, A?, ALI e L? marcadores de especificidade. Buscou-se, ainda, verificar a ocorr?ncia de implicaturas conversacionais (GRICE, 1982) nos contextos de uso de AQUI, A?, ALI e L? marcadores de especificidade. Em seguida, procurou-se esbo?ar uma poss?vel trajet?ria de gramaticaliza??o por que AQUI, A?, ALI e L? marcadores de especificidade passaram, a partir de sua fun??o fonte de d?iticos espaciais, at? virem a integrar o SN indefinido
63

Os efeitos de sentidos da formulação das regras e os acréscimos nas gramáticas de Julio Ribeiro, Said Ali e Evanildo Bechara / The effects of senses of formulation of the rules and the increases in grammars of Julio Ribeiro, Said Ali and Evanildo Bechara

Santos, Gleide Amaral dos, 1948- 23 August 2018 (has links)
Orientador: Carolina Maria Rodríguez Zuccolillo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-23T00:03:46Z (GMT). No. of bitstreams: 1 Santos_GleideAmaraldos_D.pdf: 2312794 bytes, checksum: c5a69120d9bd73d74f46910e0664b1d0 (MD5) Previous issue date: 2013 / Résumé: Cette thèse, inscrite dans l'histoire des idées en commun avec Linguistique Analyse du discours, vise à analyser les effets des sens la formulation discursive des règles et des ajouts dans les grammaires Julio Ribeiro, Said Ali et Evanildo Bechara. Si ces règles de grammaire et des textes qui, ici, nous appelons ajouts grammaticales, ce qui nous considérons leurs discours, concernant la langue del'externalité, étant entendu que cette relation est la constitution mutuelle. En conséquence, nous analysons la rédaction de procédures de la règle, compte tenu de ce qui se passe dans le corps du texte et les notes et commentaires, en tenant compte des conditions particulières de grammatisation au Brésil. Les questions qui guident notre étude sont les suivantes: Comment les images de l'intégralité de la langue? Comme ce sujet se pose par rapport à la langue, au Brésil, en tenant compte des conditions spécifiques de grammatisation? Quel genre de "incomplétude", c'est que si vous voulez "remplir" les grammaires brésiliens? Quelle est votre relation avec la tension entre la langue - la norme - du Portugal et le Brésil? Voici, d'abord, le concept des langues grammatisation, processus qui inclut la question de la formulation de la règle et la norme. Dans un second temps, nous traitons les règles et les ajouts discours historico-grammaticale sur le terrain, discuter de la standardisation de la langue, à travers les règles. Nous avons également discuté de la question de la production de connaissances sur la langue, pour voir comment il donne la formulation de règles et ajouts des grammaires sélectionnés et a ensuite fait un sur vol des parties de grammaires, la coupe des règles spécifiques d'analyse de la mise pronoms atones, en cherchant à réaliser la mise en place de la règle, la formulation de règles et ajouts des grammaires brésiliens / Resumo: Essa tese, inscrita no domínio da História das Ideias Linguísticas em articulação com a Análise de Discurso, tem como objeto analisar discursivamente os efeitos de sentidos da formulação das regras e os acréscimos nas gramáticas de Julio Ribeiro, Said Ali e Evanildo Bechara. Foram essas regras gramaticais e os textos, que aqui chamamos de acréscimos gramaticais, que nos fizeram considerar suas discursividades, relacionando a linguagem à exterioridade, entendendo que esta relação é de constituição mútua. Nesse sentido, procuramos analisar os procedimentos de formulação da regra, tendo em vista o que vai no corpo do texto e nas notas e comentários, considerando as condições particulares da gramatização no Brasil, país de colonização portuguesa. As perguntas que norteiam nossa reflexão são: Como se constrói o imaginário da completude da língua? Como esse sujeito se coloca em relação à língua no Brasil, em relação à língua de Portugal? Que tipo de "incompletude" é que se procura "preencher" nas gramáticas brasileiras? Qual sua relação com a tensão entre a língua - a norma - de Portugal e do Brasil? Apresentamos, primeiramente, o conceito de gramatização das línguas, processo em que se insere a questão da formulação da regra e da norma. Em um segundo momento, tratamos das regras e dos acréscimos gramaticais no domínio histórico-discursivo, discutindo a normatização da língua, por meio das regras. Discutimos também a temática da produção do saber sobre a língua, para verificar de que modo se dá a formulação das regras no corpo do texto e nos acréscimos nas gramáticas selecionadas e em seguida fizemos uma apresentação geral das partes dessas gramáticas trazendo algumas regras gerais para análise e recortando para a análise específica as regras de colocação dos pronomes átonos, procurando perceber a instituição da norma, pela formulação das regras e os acréscimos nas gramáticas brasileiras / Abstract: This thesis, entered the field of Linguistic History of Ideas in a linkage with the Discourse Analysis, aims at analyzing the discursive the effects of senses of formulation of rules and increases in grammars Julio Ribeiro, Said Ali and Evanildo Bechara. These were the texts and grammar rules, which here we call grammatical increases, we did consider his discoursivities, relating the language to exteriority, understanding that this relationship is of mutual constitution. Accordingly, we analyze the procedures for formulating the rule, in view of what is in the body of the text and the notes and comments, considering the particular conditions of grammatisation in Brazil, country of Portuguese colonization. The questions that guide our reflection are: How do you build the imaginary completeness of the language? How this subject arises in relation to language in Brazil compared the language of Portugal? What kind of "incompleteness" is that it seeks to "fill" the Brazilian grammars? What is your relationship with the tension between the language - the norm - of Portugal and Brazil? Here, firstly, the presentation of the concept of grammatisation languages, process which includes the issue of formulation of the rule and the norm. In a second step, we treat the rules and increases grammatical in the field historical-discursive, discussing the standardization of the language, through the rules. We also discussed the issue of the production of knowledge about the language, to see how it gives the formulation of rules in the body of the text and in the increases in selected grammars and then made a general presentation of parts of grammars, bringing some general rules for analysis and cutting to specific analysis, rules for placement of atonic pronouns, seeking to realize the establishment of the norm, for the rules formulation and the increases in Brazilian grammars / Doutorado / Linguistica / Doutora em Linguística
64

The agricultural policy of Mahomet Ali in Egypt

Rivlin, Helen Anne B. January 1953 (has links)
No description available.
65

Concept of jihād and baghy in Islamic law : with special reference to Ibn Taymiyya

Sharif, Mohd Farid bin Mohd January 2006 (has links)
This thesis is about Ibn Taymiyya's thinking on jihād and baghy. It aims to make an important contribution to the study of early Islamic political thought. It considers how the terms jihād and baghy have developed and been expanded from the structure established by the Qur'an and hadith. It also examines the relationship between jihād and baghy in Islamic law and reveals the pivotal role of the imām in politics. The main focus of this study is Ibn Taymiyya's thinking on jihād and the fatwās that resulted from it, using hitherto overlooked printed materials. It also seeks to explain why Ibn Taymiyya upheld jihād against the Mongols, the Franks and the heretic Shī'a. The thesis is divided into four chapters and structured as follows. The first chapter deals with the life of Ibn Taymiyya. This chapter moves beyond conventional biography to relate the story of Ibn Taymiyya's life to the main events that occurred during the Mongols' incursion. The second chapter identifies what Meccan and Medinan Qur'anic texts say about jihād, and examines whether jihād is a mechanism of self defense or an act of aggression; it also explains the relationship between jihād and the establishment of dār al-Islām, dār al-ḥarb and dār al-'ahd. The third chapter considers Ibn Taymiyya's view on jihād. The fourth chapter analyses Ibn Taymiyya's view on baghy, and aims to arrive at a clearer picture of the relationship between Ibn Taymiyya's concepts of jihād and baghy.
66

Surviving Modernity: Ashraf 'Ali Thanvi (1863-1943) and the Making of Muslim Orthodoxy in Colonial India

Mian, Ali Altaf January 2015 (has links)
<p>This dissertation examines the shape, substance, and staging of Muslim orthodoxy in British India, concentrating on how orthodox theologians survived colonial modernity by deploying sociological, discursive, psychic, and hermeneutical strategies. This dissertation is organized around Ashraf `Ali Thanvi (1863-1943), a leading Muslim theologian, mystic, and jurist of colonial India. Thanvi authored hundreds of original treatises, compiled texts, and works of commentary on doctrine and ritual, mystical experience, communal identity, and political theology. His collected letters, recorded conversations, and sermons were published within his lifetime and continue to instruct many contemporary South Asian Muslims. I closely read Thanvi's texts and situate them within two frameworks: the history of Indo-Muslim thought and the socio-political history of colonial India. Thanvi's hundreds of published treatises and sermons, continued citation within South Asian Islam, and widespread sufi fellowship make him one of the most compelling case studies for analyzing some of the key thematic concerns of Muslim orthodoxy, such as religious knowledge, self-discipline, sublimation of desire, regulation of gender, and communalist politics. My analyses demonstrate how orthodox scholars proliferated their theological, legal, and mystical teachings in order to make tradition relevant and authoritative in the public and private lives of many South Asian Muslims. Orthodox Islam not only survived colonial modernity, but also thrived in its ideological and social contexts.</p> / Dissertation
67

Examensarbete Saz : stilanalysarbete Mohamed Abdelkarim- Bizqens prins

Ali Shaker, Alex Ali January 2016 (has links)
Sammanfattning  Efter att ha skrivit biografin om Mohamad Abdelkarim och analyserat hans olika stilar genom att skriva noter till melodierna så har jag förstått ännu mer varför Mohamad anses vara en av dem som genom historien haft bäst teknik och känsla för sitt instrument, Bizq. Han behärskade instrumentet och var väldigt självsäker i sin musik. Han hade rest runt, bekantat sig med många olika kulturer och tagit influsenser av respektive kultur, vilket gör honom till en unikt mångsidig instrumentalist och komponist. Jag har lärt mig mycket teknik om instrumentet genom att försöka spela låtarna som Mohamad gjorde. / Biografi Ali shaker  Ali Ali känd som Ali Shaker, föddes år 1985 i staden Hassake i den syriska delen av Kurdistan. Ali växte upp i en musikalisk familj- hans pappa sjöng kurdisk folkmusik på fritiden och hans storebror spelade saz och buzuq. Själv började Ali spela darbukka, arabisk trumma, samtidigt som han började skolan. När Ali skulle börja andra klass, dvs. när han var 8 år gammal började han spela trummor på bröllop och mindre fester för att kunna försörja sin familj. Det hände ofta att Ali blödde i händerna då han var tvungen att spela i flera timmar- det var ju hans jobb.  När Ali var 13 år gammal började han spela saz då det var lättare instrument att spela i flera timmar i sträck, det var därför han började spela saz på bröllop. Dessutom är instrumentet en viktig del av den kurdiska vardagen- det finns nästan i varje kurdiskt hem i Syrien. Vid 17 års ålder började ryktet om en duktig sazspelare sprida sig i Hassake-regionen. 19 år gammal kallas Ali in för att göra lumpen i huvudstaden Damaskus. Ali hade tur som blev placerad just där, då alla kända studior var där. Ali började visa framfötterna och snart var han känd bland de flesta verksamma musiker i landet. Efter lumpen började Ali även verka utomlands. I bl.a. Beirut och Dubai, som är navet för arabisk popmusik har Ali medverkat i en otalig mängd låtar och skivor, tillhörande många av arabvärldens största stjärnor. En dröm kvarstod dock- att studera musik på en hög akademisk nivå, en dröm som inte var möjlig tidigare efetrsom Ali var tvungen att jobba hela tiden och hjälpa sin familj. I början på år 2012 flyttade Ali till Sverige, efter att ha gift sig med den kända kurdiska sångerskan Narin Feqe. Han började snabbt att ta de steg som krävdes för att förverkliga sin dröm och studera musik, och det gick snabbt. År 2013 började Ali studera folkmusik från andra kulturer på Kungliga Musikhögskolan.
68

Imigranti v metropoli / Immigrants in the Metropolis

Dongresová, Marta January 2015 (has links)
Urban spaces have appeared in literature for a long time and they seem to fascinate a lot of contemporary writers. The constructions of cities become exceptionally complex in postcolonial British fiction that portrays urban landscape from the perspective of first and second generation immigrants from Britain's former colonies. All of the novels discussed in this work are set in London and the characters are immigrants of the South Asian and Caribbean diasporas in Britain: the thesis focuses namely on Brick Lane (Monica Ali), White Teeth (Zadie Smith) and Life Isn't All Ha Ha Hee Hee (Meera Syal). However, the work also makes short digressions to a number of older works which deal with the immigrant experience in London: The Lonely Londoners (Sam Selvon), The Satanic Verses (Salman Rushdie) and The Buddha of Suburbia (Hanif Kureishi). The entire thesis consists of five parts and begins with an introduction to several theoretical terms that are necessary for analyses of immigrant identities and urban spaces. All of the theory that is discussed in the first chapter is then applied to the chosen novels by Ali, Smith and Syal. Overall, the thesis focuses on the ways in which the ex-colonial subjects in the books perceive London according to their gender and the particular generation of immigrants that...
69

Avaliação do citoesqueleto e da barreira endotelial pulmonar na malária experimental / Evaluation of the cytoskeleton and pulmonary endothelial barrier in experimental malaria

Debone, Daniela 20 April 2017 (has links)
Infecções por Plasmodium sp. podem levar a um quadro respiratório grave, com complicações pulmonares denominadas lesão pulmonar aguda e síndrome do desconforto respiratório agudo (LPA/SDRA). Inflamação aguda, lesão do endotélio alveolar e do parênquima pulmonar, disfunção e aumento da permeabilidade da barreira alvéolo-capilar e, consequente, formação de edema, caracterizam esta síndrome. O modelo experimental, que utiliza o parasita murino Plasmodium berghei ANKA e camundongos da linhagem DBA/2, é empregado no estudo de mediadores imunológicos e fatores que propiciam o estabelecimento das lesões pulmonares associados à LPA/SDRA. Diversos estímulos podem atuar diretamente no aumento da permeabilidade endotelial por meio da desestabilização dos microtúbulos, rearranjo dos microfilamentos de actina e contração das células endoteliais, via sinalização de Rho-GTPases, causando disfunção da barreira endotelial. Desta forma, este trabalho tem como objetivo avaliar as alterações do citoesqueleto em células endoteliais primárias pulmonares de camundongos DBA/2 (CEPP-DBA/2), as vias de sinalização das principais Rho-GTPases e o estresse oxidativo, causados pela presença de eritrócitos parasitados com esquizontes de P. berghei ANKA (EP-PbA). As CEPP-DBA/2 foram estimuladas com TNF, VEGF ou IFN&#947;, em diferentes tempos de exposição, seguido da incubação com EP-PbA. Assim, foram realizados ensaios de imunofluorescência para análise do rearranjo de microfilamentos de actina e da desestabilização de microtúbulos. As vias de sinalização das Rho-GTPases foram avaliadas por Western blot, para as expressões proteicas de RhoA, Cdc42 e MLC. Além disso, ensaio fluorométrico foi realizado para detectar a produção de espécies reativas de oxigênio, resultantes do estímulo com eritrócitos parasitados. CEPP-DBA/2 estimuladas por EP-PbA, VEGF, TNF ou IFN&#947;, em associação ou não, apresentaram alterações morfológicas nos microfilamentos de actina e aumento dos espaços interendoteliais. Imagens de imunofluorescência também mostram desestabilização de microtúbulos e desfosforilação de FAK, causadas por EP-PbA. Os ensaios de permeabilidade validam que os eritrócitos parasitados com formas maduras de P. berghei induziram aumento da permeabilidade microvascular nas CEPP-DBA/2. Além disso, estas células, estimuladas com EP-PbA, demonstraram elevada produção de espécies reativas de oxigênio (EROs), o que pode estar contribuindo com o desenvolvimento de estresse oxidativo e com a injúria endotelial, assim como, com o aumento da permeabilidade vascular. O mais interessante é que estas alterações endoteliais podem estar relacionadas ao aumento da razão RhoA/Cdc42, da expressão proteica de MLC fosforilada e do sinal de ativação de RhoA. Em conjunto, estes resultados mostram envolvimento dos eritrócitos parasitados com esquizontes de Plasmodium berghei ANKA na desorganização do citoesqueleto e na disfunção da barreira alvéolo-capilar, via RhoA/Rho-kinase, o que pode estar contribuindo com a patogênese da LPA/SDRA associada à malária. / Infections by Plasmodium sp. can lead to a serious respiratory condition with pulmonary complications, named acute lung injury and acute respiratory distress syndrome (ALI/ARDS). Acute inflammation, alveolar endothelium and lung parenchyma injuries, dysfunction and increased permeability of the pulmonary alveolar-capillary barrier and consequent formation of edema characterize this syndrome. Several stimuli can directly increase endothelial permeability through actin microfilaments rearrangement, via Rho- GTPases signaling, leading to endothelial barrier dysfunction. DBA/2 mice infected with Plasmodium berghei ANKA develop ALI/ARDS similar to that observed in humans. The purpose of this research was to assess cytoskeletal changes in DBA/2 mice primary microvascular lung endothelial cells (PMLEC), verify the signaling pathways of the Rho- GTPases and analyze the oxidative stress on these cells in the presence of P. berghei ANKA-infected red blood cells (PbA-iRBC). PMLEC were stimulated by TNF, VEGF or IFN&#947; followed by incubation with PbA-iRBC. Immunofluorescence assays were performed to analyze actin microfilaments rearrangement and microtubules destabilization. Western blot for RhoA, Cdc42 and MLC proteins were conducted to assess alterations in signaling pathways of Rho-GTPases. In addition, a fluorimetric assay was performed to detect the production of reactive oxygen species resulting from PbA-iRBC stimulus. P. berghei ANKA, VEGF, TNF and IFN&#947; stimuli, in association or not, caused morphological disturbances in actin microfilaments of PMLEC and an increase of intercellular spaces. Moreover, immunofluorescence images showed microtubules destabilization and FAK dephosphorylation in these cells, caused by PbA-iRBC. The permeability assay showed that PbA-iRBC induced an increase of microvascular permeability in PMLEC. In addition, PMLEC stimulated by PbA-iRBC, showed elevated production of ROS, which may be contributing to oxidative stress and increasing the damage of endothelial cells, as well as an increase of vascular permeability. Interestingly, these endothelial changes may be related to the increased RhoA/Cdc42 protein expressions ratio, augmented protein expression of phosphorylated MLC and RhoA activation signal. Taken together, these data demonstrate the involvement of P. berghei ANKA-infected red blood cells in cytoskeleton disorganization and alveolar-capillary barrier dysfunction, through of RhoA / Rho-kinase signaling pathway, which may contribute to ALI/ARDS pathogenesis.
70

Pulmonary toxicity assessment following aerosolization of engineered nanomaterials using an in vitro air-liquid interface method

Wang, Yifang 01 August 2019 (has links)
Although there are over 1,600 Engineered Nanomaterials (ENMs)-containing consumer products available, our understanding of ENM safety is still limited. Airborne ENMs can readily enter the human body through inhalation potentially leading to many adverse health effects such as cardiovascular and pulmonary diseases. The conventional in vitro submerged cell culture method was developed decades ago and has been widely used as a fast screening method to elucidate cellular toxicity upon exposure to hazardous materials; however, it has many limitations compared with the in vivo models. Our group has previously utilized and validated an integrated low flow system capable of generating and depositing airborne nanoparticles (NPs) directly onto cells at an air-liquid interface (ALI) condition, and our results confirmed that this exposure system produced reproducible toxicological data for ENMs including gold (Au), 16% silver coated onto silica (16% Ag-SiO2), and copper oxide (CuO). To further improve this ALI method for an even closer representation of the in vivo model, a co-culture model containing three cell lines (A549, THP-1 differentiated macrophages, and EA.hy 926) was established and validated for testing ENMs toxicity. The co-culture model was exposed to 16% Ag-SiO2 and CuO NPs under the same protocol (4 h ALI exposure with a concentration of 3.5 mg/m3) as monoculture (A549 only) for comparison. Toxicity was assessed by measuring cell viability, reactive oxygen species (ROS) production, lactate dehydrogenase (LDH) release, and interleukin (IL) 8 level. Results showed that 16% Ag-SiO2 NPs induced higher ROS generation, and CuO NPs produced a significant level of proinflammatory response compared with monoculture. In addition, the co-culture model exhibited a similar response with the primary human bronchial epithelia cell line (HBEC) in terms of ROS and IL-8 responses after CuO NPs exposure, suggesting a more advanced refinement of the conventional model for in vitro inhalation study.

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