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Alienation In Marx And BaudrilliardYelman, Sirel 01 February 2012 (has links) (PDF)
Alienation is a one of the central concepts in Marx&rsquo / s philosophy. It has positive and negative implications regarding man&rsquo / s self realization in nature. It is also about discussion on ontology of work. Moreover, it has led Marx to design new society models for human beings. Alienation in Marx is analyzed together with political economy and its concepts. Baudrilliard&rsquo / s alienation discourses in contemporary age include arguments in terms of consumerism and technology in today&rsquo / s developed world. While Marx&rsquo / s theory of alienation considers the relation of subject and object in political economic conditions, Baudrilliard&rsquo / s discourses discuss it in social and cultural bases. Baudrilliard rather argues that reality and meaning in contemporary world is lost, we live in a &ldquo / hyperreal&rdquo / and &ldquo / simulacrum&rdquo / world.
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A Study On Dikaiosune And Eudaimonia In Plato' / s RepublicSentuna, Eylul 01 February 2012 (has links) (PDF)
The aim of this study is to analyze the concept on dikaiosune in Plato' / s Republic with its main aspects. Republic as an overarching philosophical work will be reviewed as a whole and the overall scheme will be taken into account. There will be an emphasis on the ethical point of view rather than a political standpoint. The main interest of the thesis is what dikaiosune is and its relationship with goodness and eudaimonia which are terms sometimes used interchangeably. Still, the intervowen concepts of virtue, happiness, fulfillment, desire and unity will be taken into consideration as also for Plato these are perpetually connected. Various commentators of the Republic, their views and arguments will also be examined and analyzed within this study.
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The Place Of Human Subject In Foucault' / s And Deleuze' / s PhilosophiesTaner, Erdem 01 November 2005 (has links) (PDF)
The main objective of this master&rsquo / s thesis is to analyze the place assigned to human subjectivity by French philosophers Michel Foucault and Gilles Deleuze. In order to fulfil the requirements of this objective, what is focused on is their shared critique which is exercised against the traditional conceptions of humanity and subjectivity. Through the thesis, first Foucault&rsquo / s analyses which demonstrate that universal man as a construction emerges as an effect of discursive practices and power relations, and his archaeological method that illustrates knowledge process is not dependent on transcendental consciousness are explained and discussed. Then it is argued that Deleuzian philosophy of becoming which does not submit to any transcendent unity that governs experience is an actual alternative to subject-centered understandings of the world. Throughout the course of arguments it is emphasized that according to both Foucault and Deleuze the human subject is an effect of network type relations that occur in a non-subjective fashion.
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The Possibility Of An Ethical Transcendental Philosophy In LevinasCiftci, Ahmet Erdem 01 November 2005 (has links) (PDF)
This study aims to accomplish two tasks: First, it is argued that an &lsquo / ethical transcendental philosophy&rsquo / is possible with Levinas. Second, the concepts that bear this possibility to a philosophically acceptable level of cogency can be clarified.
Philosopher&rsquo / s position in history of philosophy suggests a kind of &lsquo / externality&rsquo / in the sense that he is not within the realm of very tradition. Levinas&rsquo / predisposition is rather to employ what he calls &lsquo / peri-phrases&rsquo / that hinder the philosopher to settle in the existing structure of concepts (read as Greek language). This position can also be read as a resistance to dominating forms of knowledge. Levinas takes this attitude as an important point of resistance against Western metaphysics that puts the ontology at the center. Against this tradition, he celebrates both the &lsquo / encounter with the Other&rsquo / as a pilot point in ethics, one that all rest of which follows from, and the priority of &lsquo / the Good&rsquo / .
In such a way, &lsquo / I&rsquo / has been put into question in its gay independence without any reference to self contained totality, of the kind which is &lsquo / self intelligible&rsquo / . This attachment that is infinition, of infinity helps us experience not a totality, but &lsquo / otherwise than being&rsquo / . This attitute might resonate with the Kantian attempt displacing knowledge in order to make room for morality. However, a closer reading would notice that there is another agenda here, one that attempts to go to a status of pre-rationality, beyond rationality, so to speak an agenda that radicalizes the Kantian attempt.
Derrida, a philosopher who showed that this attempt was just impossible, impossible in the sense that it was contaminated at the very beginning, skillfully benefits from the very inspiration Levinas has provided with. All these attempts and conceptual suggestions have been examined and analyzed, and the Levinasian inspiration has been tried to be elucidated.
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Ethico-political Acts Of DesireBalanuye, Cetin 01 April 2006 (has links) (PDF)
The concept of desire has been central to most recent philosophical debates, in various forms and styles. I have argued in the present study that, one of the main motivations for this apparent interest in the concept of desire is the result of the increasing awareness of the shortcomings of those presuppositions revolving around an &ldquo / autonomous subject&rdquo / , &ldquo / transcendence&rdquo / , &ldquo / representation&rdquo / , and &ldquo / moral subjectivity&rdquo / . Desire, in this vein, is conceived and put into practice by the traditional philosophy as one among the other attributes that cannot be considered without reference to man. Desire as such is conceived as something that is necessarily controlled and managed by reason. Ethics and politics, in terms of these ill-conceived presuppositions, are narratives erected upon this tension that necessarily refers to a self-conscious subject and her subversive desires.
I argue, in this study, for the possibility of imagining other variants of desire, i.e., something other than traditionally established debates, where desire is no longer conceived in strict reference to human beings. These novel accounts, which I will attempt to uncover, hope, will help us see in what ways desire can be considered within the concept of pure immanence and the realm post-humanist ethico-politics. Spinoza, Nietzsche and certainly Deleuze and Guattari are on this side. Desire, according to this non-tradition, belongs to immanence.
In arguing for the legitimacy of two affirmative notions of desire, namely, that of immanent desire and embodied desire, I tried to establish a continuity between immanence (totality of bodies and constant differing) and embodied desire (singular intensities), and by means of which I have drawn attention to the importance of a new vision of ethics and politics that might work, not through the already established form of subjectivities, but through new forms of individuation and flow-like encounters of bodies.
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The Structure Of Scientific Community And Its Relevance To Science EthicsOzdemir, Ece Ozge 01 June 2006 (has links) (PDF)
The goal of this thesis is to argue that science is not value free on the grounds of a community based account of ethics. It is the peculiar feature of this model that ethics is a limitation on individual' / s freedom of action, and moral norms of a community reflect the structure of the community. I endeavour to resolve the problem, on an assumption that science is an activity of scientific community, that science ethics can be derived from the internal structure of scientific community. Therefore, this thesis attempts to show the relationship between scientific community and science ethics.
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Why the Big 5? : understanding UK seafood consumer behaviourTetley, Sarah January 2016 (has links)
UK consumers bought just under 500 thousand tonnes of seafood in 2010, at a cost of £3.8bn. Despite rising prices, consumption is on a general upwards path, with the average UK adult now eating 2% more seafood than they would have eaten a generation ago, and demand predicted to grow by a further 17% by 2030. However, this demand is increasingly restricted to a narrow range of imported and wild-caught species (Cod, Haddock, Tuna) and farmed products (Salmon and Prawns) over locally-available species with the consequence that between 60% and 80% of UK domestic landings are currently exported and 80% of all the seafood eaten in the UK is one of either Cod, Haddock, Salmon, Tuna or Prawns – the so-called Big 5. The shortage of local markets for native fish species is arguably reducing the relative viability of small scale, over large-scale, fisheries in the UK. It also increases pressure upon wild stocks of commercially valuable species and is driving the rapid expansion of fish-farming operations which can have negative environmental and social implications. Considering the above, it is suggested that UK consumers could make a positive contribution to the UK economy and marine environment if they chose to buy native, locally-caught species, over farmed and exotic imports. In order to achieve this, however, significant behavioural change would need to take place; and for behavioural change initiatives to be successful, it is argued that it is first necessary to understand why these consumption patterns have developed, i.e. Why the Big 5? Accepting that no single theory has been found that can fully explain behaviours from intentions, this research used mixed methods to develop a consumer-centric view of the full range of factors that might be driving these unsustainable consumption patterns. Regular consumers of seafood from four contrasting localities in England were recruited to complete surveys, maintain shopping diaries and to take part in group and one-to-one interviews to understand their reasons for eating seafood in general and the Big 5 in particular. Drawing on the Literature on seafood consumption, demographic and geographic-induced differences in consumption were explored; and consumer understanding of, and concern for, the sustainability of their seafood was assessed. Retail behaviour was also examined by undertaking an on-line review of the seafood offered for sale by the UK’s five largest retailers. Consumers were generally ill informed and confused about the sustainability of their seafood and had little to no awareness of labelling. In their confusion/apathy, they tended to revert to habitual behaviours and safe choices tending towards the Big 5. They felt strongly that retailers should be making it easier for them to make sustainable choices. The evidence from this study is that Retail is failing in this respect. Interest in and demand for local seafood was very high, with consumers equating local with sustainable, even though the evidence to support this assertion is currently lacking. Consumer definitions of “local” and “sustainable” were found to vary from accepted policy and academic understanding, presenting the possibility of adding to consumer confusion when communicating about sustainable seafood; further, “sustainable” possessed negative connotations for these consumers who, in stark contrast to the average UK consumer, were found to score highly for Hedonism. In total, twenty eight distinct variables were identified as influencing unsustainable UK seafood consumer behaviour. Key amongst these were consumer ignorance/apathy regarding sustainability; retail behaviour; and habit – factors that are presented in the Trifold Model of Unsustainable Consumer Behaviour. This model brings much needed clarity to a complex and poorly understood area of consumer behaviour and marks a significant contribution to three areas of academic study: Sustainable Consumption; Consumer Behaviour; and Business Ethics. The Trifold Model is presented for further testing. Recommendations for policy and industry are highlighted as are areas for further research.
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Recruiting ethical expertise : the roles of lay and expert members in NHS Research Ethics CommitteesHapeshi, Julie E. January 2014 (has links)
Drawing on the classification of expertise developed by Collins and Evans, this study explores the expertises held by members of NHS Research Ethics Committees (RECs) and how they differ from the ones described by the regulations. The study used Q methodology followed by ten semi-structured interviews with Lay and Expert REC members. The results show that committee members see themselves as part of a team, with individual members making different contributions to a collective task. Viewing REC members in this way allows their different expertises to be formally recognised and leads to the creation of two new membership categories, specialist and generalist, based on these expertises. Specialists have expertises such as statistics and pharmacy that are required by the current legislation and which would be present on recruitment. Generalists possess the other expertises needed by the committee but which not required by statute. These include the clinical expertises possessed by healthcare professionals and the other professional expertises – legal, academic, IT and so on – that are typically found amongst those currently classed as Lay members. All REC members, be they specialist or generalist, would also be trained in the ethical and regulatory expertises required to deliver an ethical review. Emphasising how all REC members, whether specialist or generalise, have expertises that contribute to the ethical review enables recruitment activities to focus on the skills needed by the committee rather than current concerns with population demographics. This provides a solution to many of the recruitment issues identified by participants. In particular, it enables the replacement of skills on a ‘like for like’ basis using clearly defined person specifications. Not only would such a process comply with the Nolan principles it be more likely to maintain the integrity and function of the committee regardless of personnel changes.
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Isolamento e caracterização funcional de uma fosfolipase A2 de Bothrops jararaca: avaliação do potencial antitumoral e inflamatório / Isolation and functional characterization of a phospholipase A2 from Bothrops jararaca snake venom: evaluation of its antitumor and inflammatory potentialAraújo, Rafhaella Carolina Cedro 02 December 2014 (has links)
As fosfolipases A2 (PLA2s) catalisam a hidrólise de ácidos graxos na posição sn-2 das membranas fosfolipídicas e liberam, como subprodutos, ácidos graxos livres. As PLA2s do grupo IIA são encontradas em peçonhas de serpentes da família Viperidae e desempenham diversas atividades apresentando potencial miotóxico, neurotóxico, hemolítico, edematogênico, citotóxico, hipotensivo, anticoagulante, inibição/ativação da agregação plaquetária, bactericida e pró-inflamatório. Esse trabalho teve como objetivo o isolamento e a caracterização funcional de uma PLA2 isolada da peçonha de Bothrops jararaca. Para a purificação dessa proteína, denominada BJ-PLA2-I, foram necessários três passos cromatográficos consecutivos: cromatografia de exclusão molecular em Sephacryl S-200, cromatografia de troca iônica em Source TM 15Q/50mL e cromatografia de troca iônica em MonoQ TM 5/50 GL. A BJ-PLA2-I apresentou elevado grau de pureza por SDS-PAGE e por cromatografia de fase reversa C18, em HPLC. Apresentou ainda, características ácidas, com pI em torno de 4,4 e teve a sua massa molecular determinada por dois métodos, obtendo-se valores bem próximos de 14,8 kDa (SDS-PAGE) e 14,2 kDa (MALDI-TOF). Esse fato é comum considerando que a espectrometria de massas é um método mais preciso e determina de maneira mais exata a massa molecular. O sequenciamento N-terminal da BJ-PLA2-I resultou em 60 resíduos de aminoácidos. O alinhamento múltiplo com outras fosfolipases A2 de serpentes do mesmo gênero mostrou similaridade entre elas, mostrando identidade de 100% com a BJ-PLA2, fosfolipase A2 Asp-49, também isolada da Bothrops jararaca. Esse dado levanta a hipótese de que a BJ-PLA2-I purificada neste trabalho e a BJ-PLA2 se tratam da mesma proteína, entretanto essa hipótese só poderá ser confirmada quando a sequência completa da BJ-PLA2-I for obtida. Outros dados encontrados neste trabalho reforçam essa hipótese, isso porque, avaliando a atividade fosfolipásica, o efeito sobre as plaquetas e o pI, tanto a BJ-PLA2-I quanto a BJ-PLA2 apresentaram características semelhantes. A BJ-PLA2-I, sendo uma Asp-49, mostrou alta atividade catalítica e efeito inibidor da agregação plaquetária induzida por ADP (20,5 ?g/mL inibiu 50 % da agregação plaquetária). Ela também foi capaz de induzir a migração leucocitária após a administração de diferentes concentrações (5, 10 e 20 ?g/mL) da BJ-PLA2-I. Esse dado também foi encontrado no ensaio em que a concentração de 10 ?g/mL foi fixada e variou-se o tempo de 2, 4 e 24 horas, observando-se principalmente a migração de neutrófilos. Além disso, verificou-se a liberação das citocinas IL-6 e IL-1?, de proteínas totais e de prostaglandina E2 na reação inflamatória induzida pela BJ-PLA2-I. No entanto, não foi observado a produção de TNF-?, IL-10 e leucotrieno B4. A BJ-PLA2-I caracterizou-se como uma PLA2 pró-inflamatória, produzindo inflamação local aguda. A BJ-PLA2-I foi avaliada quanto ao seu potencial antitumoral em três linhagens celulares distintas (PBMC, HL-60 e HepG2). Observou-se que a enzima em questão possui baixo potencial antitumoral para a linhagem HL-60, reduzindo o número de células tumorais em apenas cerca de 20% nas concentrações testadas. Verificou-se pequena alteração na viabilidade celular das células de PMBC, nas maiores concentrações testadas (160 e 80 ?g/mL) e, na linhagem HepG2 não foi encontrada nenhuma alteração. Concluindo, as informações adquiridas neste trabalho são de suma importância para a melhor compreensão dos mecanismos envolvidos nas atividades biológicas desempenhadas pelas PLA2s. Além disso, a BJ-PLA2-I pode servir como modelo molecular para a formulação de fármacos mais eficazes a serem utilizados no tratamento de várias doenças. / Phospholipases A2 (PLA2s) catalyze the hydrolysis of fatty acids in the sn-2 position of membrane phospholipids, releasing free fatty acids as by-products. PLA2s of group IIA are found in snake venoms of the Viperidae family and perform various activities, including myotoxic, neurotoxic, hemolytic, edematogenic, cytotoxic, hypotensive, anticoagulant, inhibition/activation of platelet aggregation, bactericidal and proinflammatory effects. This work aimed at the isolation and functional characterization of a PLA2 isolated from Bothrops jararaca venom. For the purification of this protein, called BJ-PLA2-I, three consecutive chromatographic steps were used (size exclusion chromatography on Sephacryl S-200, ion exchange chromatography on Source 15Q/50 mL, ion exchange chromatography on MonoQ 5/50 GL). Confirmation of the purity of BJ-PLA2-I was evaluated by SDS-PAGE and reverse phase HPLC using a C18 column. BJ-PLA2-I has acidic characteristics, with pI around 4.4, and its molecular mass was determined by two methods, obtaining values close to 14.8 kDa (SDS-PAGE) and 14.2 kDa (MALDI-TOF). The N-terminal sequencing of BJ-PLA2-I resulted in 60 amino acid residues. Multiple alignment with other phospholipases A2 of snakes of the same genus showed high similarity between them, showing 100% identity with BJ-PLA2, an Asp-49 phospholipase A2 previously isolated from Bothrops jararaca venom. This finding raises the possibility that the PLA2 purified in this work is the same protein previously described (BJ-PLA2), however, this assumption can only be confirmed when the complete sequence of BJ-PLA2-I is obtained. Other data obtained in this study support this hypothesis, considering that the phospholipase activity, the effect on platelets and pI of both BJ-PLA2-I and BJ-PLA2 showed to be similar. BJ-PLA2-I, being an Asp-49 PLA2, showed high catalytic activity and inhibitory effect on the platelet aggregation induced by ADP (20.5 ?g/mL inhibited 50% of the platelet aggregation). It was also able to induce leukocyte migration after the administration of different concentrations (5, 10 and 20 ?g/mL) of BJ-PLA2-I. This fact was also found when the concentration of 10 ?g/mL was fixed and response times were varied (2, 4 and 24 hours), observing especially neutrophil migration. Furthermore, there was a release of IL-6 and IL-1?, total proteins and prostaglandin E2 in the inflammatory reaction induced by BJ-PLA2-I, however, the production of TNF-?, IL-10 and leukotriene B4 was not observed. BJ-PLA2-I was characterized as a proinflammatory PLA2 producing acute local inflammation. BJ-PLA2-I was evaluated for its antitumor potential on three different cell lines (PBMC, HL-60 and HepG2). It was observed that this enzyme showed a low antitumor potential on HL-60 tumor cell line, reducing the number of tumor cells in only about 20% at the concentrations tested. There was little change in cell viability of PBMC cells in the higher concentrations tested (80 and 160 ?g/mL), but no change was found on HepG2 tumor cell line. In conclusion, the information obtained in this work are of utmost importance for better understanding the mechanisms involved in the biological activities induced by PLA2s. Furthermore, BJ-PLA2-I may serve as a molecular model for the formulation of more effective drugs to be used in the treatment of various diseases.
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Isolamento e caracterização funcional de uma fosfolipase A2 de Bothrops jararaca: avaliação do potencial antitumoral e inflamatório / Isolation and functional characterization of a phospholipase A2 from Bothrops jararaca snake venom: evaluation of its antitumor and inflammatory potentialRafhaella Carolina Cedro Araújo 02 December 2014 (has links)
As fosfolipases A2 (PLA2s) catalisam a hidrólise de ácidos graxos na posição sn-2 das membranas fosfolipídicas e liberam, como subprodutos, ácidos graxos livres. As PLA2s do grupo IIA são encontradas em peçonhas de serpentes da família Viperidae e desempenham diversas atividades apresentando potencial miotóxico, neurotóxico, hemolítico, edematogênico, citotóxico, hipotensivo, anticoagulante, inibição/ativação da agregação plaquetária, bactericida e pró-inflamatório. Esse trabalho teve como objetivo o isolamento e a caracterização funcional de uma PLA2 isolada da peçonha de Bothrops jararaca. Para a purificação dessa proteína, denominada BJ-PLA2-I, foram necessários três passos cromatográficos consecutivos: cromatografia de exclusão molecular em Sephacryl S-200, cromatografia de troca iônica em Source TM 15Q/50mL e cromatografia de troca iônica em MonoQ TM 5/50 GL. A BJ-PLA2-I apresentou elevado grau de pureza por SDS-PAGE e por cromatografia de fase reversa C18, em HPLC. Apresentou ainda, características ácidas, com pI em torno de 4,4 e teve a sua massa molecular determinada por dois métodos, obtendo-se valores bem próximos de 14,8 kDa (SDS-PAGE) e 14,2 kDa (MALDI-TOF). Esse fato é comum considerando que a espectrometria de massas é um método mais preciso e determina de maneira mais exata a massa molecular. O sequenciamento N-terminal da BJ-PLA2-I resultou em 60 resíduos de aminoácidos. O alinhamento múltiplo com outras fosfolipases A2 de serpentes do mesmo gênero mostrou similaridade entre elas, mostrando identidade de 100% com a BJ-PLA2, fosfolipase A2 Asp-49, também isolada da Bothrops jararaca. Esse dado levanta a hipótese de que a BJ-PLA2-I purificada neste trabalho e a BJ-PLA2 se tratam da mesma proteína, entretanto essa hipótese só poderá ser confirmada quando a sequência completa da BJ-PLA2-I for obtida. Outros dados encontrados neste trabalho reforçam essa hipótese, isso porque, avaliando a atividade fosfolipásica, o efeito sobre as plaquetas e o pI, tanto a BJ-PLA2-I quanto a BJ-PLA2 apresentaram características semelhantes. A BJ-PLA2-I, sendo uma Asp-49, mostrou alta atividade catalítica e efeito inibidor da agregação plaquetária induzida por ADP (20,5 ?g/mL inibiu 50 % da agregação plaquetária). Ela também foi capaz de induzir a migração leucocitária após a administração de diferentes concentrações (5, 10 e 20 ?g/mL) da BJ-PLA2-I. Esse dado também foi encontrado no ensaio em que a concentração de 10 ?g/mL foi fixada e variou-se o tempo de 2, 4 e 24 horas, observando-se principalmente a migração de neutrófilos. Além disso, verificou-se a liberação das citocinas IL-6 e IL-1?, de proteínas totais e de prostaglandina E2 na reação inflamatória induzida pela BJ-PLA2-I. No entanto, não foi observado a produção de TNF-?, IL-10 e leucotrieno B4. A BJ-PLA2-I caracterizou-se como uma PLA2 pró-inflamatória, produzindo inflamação local aguda. A BJ-PLA2-I foi avaliada quanto ao seu potencial antitumoral em três linhagens celulares distintas (PBMC, HL-60 e HepG2). Observou-se que a enzima em questão possui baixo potencial antitumoral para a linhagem HL-60, reduzindo o número de células tumorais em apenas cerca de 20% nas concentrações testadas. Verificou-se pequena alteração na viabilidade celular das células de PMBC, nas maiores concentrações testadas (160 e 80 ?g/mL) e, na linhagem HepG2 não foi encontrada nenhuma alteração. Concluindo, as informações adquiridas neste trabalho são de suma importância para a melhor compreensão dos mecanismos envolvidos nas atividades biológicas desempenhadas pelas PLA2s. Além disso, a BJ-PLA2-I pode servir como modelo molecular para a formulação de fármacos mais eficazes a serem utilizados no tratamento de várias doenças. / Phospholipases A2 (PLA2s) catalyze the hydrolysis of fatty acids in the sn-2 position of membrane phospholipids, releasing free fatty acids as by-products. PLA2s of group IIA are found in snake venoms of the Viperidae family and perform various activities, including myotoxic, neurotoxic, hemolytic, edematogenic, cytotoxic, hypotensive, anticoagulant, inhibition/activation of platelet aggregation, bactericidal and proinflammatory effects. This work aimed at the isolation and functional characterization of a PLA2 isolated from Bothrops jararaca venom. For the purification of this protein, called BJ-PLA2-I, three consecutive chromatographic steps were used (size exclusion chromatography on Sephacryl S-200, ion exchange chromatography on Source 15Q/50 mL, ion exchange chromatography on MonoQ 5/50 GL). Confirmation of the purity of BJ-PLA2-I was evaluated by SDS-PAGE and reverse phase HPLC using a C18 column. BJ-PLA2-I has acidic characteristics, with pI around 4.4, and its molecular mass was determined by two methods, obtaining values close to 14.8 kDa (SDS-PAGE) and 14.2 kDa (MALDI-TOF). The N-terminal sequencing of BJ-PLA2-I resulted in 60 amino acid residues. Multiple alignment with other phospholipases A2 of snakes of the same genus showed high similarity between them, showing 100% identity with BJ-PLA2, an Asp-49 phospholipase A2 previously isolated from Bothrops jararaca venom. This finding raises the possibility that the PLA2 purified in this work is the same protein previously described (BJ-PLA2), however, this assumption can only be confirmed when the complete sequence of BJ-PLA2-I is obtained. Other data obtained in this study support this hypothesis, considering that the phospholipase activity, the effect on platelets and pI of both BJ-PLA2-I and BJ-PLA2 showed to be similar. BJ-PLA2-I, being an Asp-49 PLA2, showed high catalytic activity and inhibitory effect on the platelet aggregation induced by ADP (20.5 ?g/mL inhibited 50% of the platelet aggregation). It was also able to induce leukocyte migration after the administration of different concentrations (5, 10 and 20 ?g/mL) of BJ-PLA2-I. This fact was also found when the concentration of 10 ?g/mL was fixed and response times were varied (2, 4 and 24 hours), observing especially neutrophil migration. Furthermore, there was a release of IL-6 and IL-1?, total proteins and prostaglandin E2 in the inflammatory reaction induced by BJ-PLA2-I, however, the production of TNF-?, IL-10 and leukotriene B4 was not observed. BJ-PLA2-I was characterized as a proinflammatory PLA2 producing acute local inflammation. BJ-PLA2-I was evaluated for its antitumor potential on three different cell lines (PBMC, HL-60 and HepG2). It was observed that this enzyme showed a low antitumor potential on HL-60 tumor cell line, reducing the number of tumor cells in only about 20% at the concentrations tested. There was little change in cell viability of PBMC cells in the higher concentrations tested (80 and 160 ?g/mL), but no change was found on HepG2 tumor cell line. In conclusion, the information obtained in this work are of utmost importance for better understanding the mechanisms involved in the biological activities induced by PLA2s. Furthermore, BJ-PLA2-I may serve as a molecular model for the formulation of more effective drugs to be used in the treatment of various diseases.
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