Mecanismos dos efeitos imunotóxicos dos nanomateriais nos peixes

Mestrado em Química - Química Analítica e QualidadeInformation and knowledge related to nanotechnology raise new challenges to the scientific community mainly in terms of human health risks and environmental implications associated to nanomaterials. In this perspective, the contamination of aquatic environments cannot be overlooked since it is an ultimate repository of the contaminants where this emerging appears as part of a cocktail of different classes of contaminants. Thus, the major task of this work was to connect gaps in current knowledge with a comprehensive sequence of biological responses toward environmentally relevant concentrations of engineered nanomaterials (IONM - silica coated iron oxide nanomaterial functionalized with dithiocarbamate group) and their interaction with other conventional anthropogenic contaminant (Hg - mercury), outlining the interaction with the innate immune system of fish. The research was divided into following steps: i) phagocytes macrophages were isolated from peritoneum (P-phagocytes), gill (G-phagocytes), head kidney (HK-phagocytes) and spleen (S-phagocytes) of European eel Anguilla anguilla L. in order to evaluate whether, and how can IONM and its co-exposure to Hg modulate phagocytes status and function; ii) determine the changes in phagocytes activation and their association to peroxidative damage (OBA - oxidative burst activity; LPO - lipid peroxidation); iii) to assess the impact of IONM on phagocytes enzymatic (CAT - catalase; GPX - glutathione peroxidase; GR - glutathione reductase; and GST - glutathione S-transferase) and non-enzymatic (NP-SH - non-protein thiols; and TGSH - total glutathione) antioxidants protection overtime. It was hypothesized that IONM can cause measurable changes in fish immune response and oxidative stress modulation. A period of exposure-dependency was exhibited by IONM alone and IONM+Hg joint exposures accrued impacts on A. anguilla phagocytes. IONM exposure alone lead to an acute response in terms of viability increase in P-phagocytes and modulated phagocytic activity in P-, and S-.phagocytes during 2 hours of exposure; whereas, IONM lead to a chronic immunotoxicity during 72 hours exposure only in S-phagocytes. However, IONM+Hg exposure lead to both acute and chronic response in terms of modulated phagocytic activity with no change in viability in P-, HK- and S-phagocytes only. Increase in the period of exposure to Hg disrupted phagocytic activity of P-, HK- and S-phagocytes, an increase in P- and decrease in HK- and S- phagocytes was perceptible at late hours of exposure. The occurrence of synergism between IONM and Hg was evidenced at 72 hours by significantly increasing trends of phagocytosis increase. A differential extent of OBA and LPO induction at the end of different period of exposure to IONM, Hg or IONM+Hg was also perceptible. The OBA induction and its concomitant association to LPO induction were observed only in gill after exposure to Hg (8 and 48 hours) and IONM+Hg (8 hours). At late hours of exposure, an induction was observed in G- phagocytes (OBA) after exposure to IONM+Hg suggesting that the concomitant exposure was unable to mitigate the Hg-accrued negative impacts. A. anguilla also displayed that the damage was accompanied with a differential modulation of enzymatic and non-enzymatic antioxidants in P, G-, HK- and S-phagocytes. Under IONM alone exposure, no LPO induction along the time was observed probably due to efficient induction of, GR and GST providing a better protection to IONM exposed phagocytes. However, antioxidants protection responses displayed hours of exposure dependency in G- and S-phagocytes where, an insufficiency of elevated CAT, GPX, GST, NP-SH and TGSH was clearly depicted for the maintenance of pro- and antioxidant balance optimum for scavenging ROS and protecting membrane lipids against IONM impact. As increased LPO was observed under IONM alone exposure condition, the joint action of IONM+Hg led to elevated damages to membrane-lipids at 4 and 8 hours (G-phagocytes), 2 hours (HK-phagocytes) and 24 hours (S-phagocytes) of exposure. These responses together, point towards the antioxidants defense failure for the protection of membrane lipids during those periods of exposure to IONM+Hg. However, it is important to underline here that during the late hours of exposure (72 hours), the results imply the positive effect of the concomitant exposure (IONM+Hg) which significantly mitigated the said negative impacts of Hg. Overall, the observations of this study open up new insight into the areas of evaluation of immune defense mechanisms in fish exposed to IONM and recommend that the interactions between IONM and other conventional anthropogenic contaminants should be considered while interpreting the fish immunotoxicity responses to IONM exposure in a multi-pollution state.Informações e conhecimentos relacionados com a nanotecnologia colocam novos desafios à comunidade científica, principalmente em termos de riscos para a saúde humana e alterações ambientais. A contaminação dos ambientes aquáticos não pode ser ignorada, uma vez que é um repositório final dos contaminantes onde estes aparecem como parte de um conjunto complexo de diferentes tipos. O objetivo principal deste trabalho foi relacionar lacunas no conhecimento atual com uma sequência de respostas biológicas, para concentrações ambientalmente relevantes de nanomateriais (ONM - nanomateriais de óxidos de ferro revestidos com sílica e funcionalizados com grupos de ditiocarbamato) e avaliar a sua interação com outros contaminantes antropogénicos, nomeadamente mercúrio (Hg), na interação com o sistema imunitário de peixes. A investigação desenvolvida foi dividida nos seguintes passos: i) os macrófagos fagocitados foram isolados da cavidade peritoneal (P-fagócitos), das guelras (G-fagócitos), da “cabeça do rim” (HK-fagócitos) e do baço (S-fagócitos) da enguia europeia Anguilla anguilla L., a fim de avaliar como podem os ONM e a sua co-exposição com o mercúrio modular o estado das fagocitoses e a sua função; ii) avaliar as alterações na ativação das fagocitoses e a sua associação ao dano peroxidativo (OBA – atividade respiratória oxidativa; LPO - peroxidação lipídica); III) avaliar o impacto das ONMs ao longo do tempo nos antioxidantes, nomeadamente fagocioses enzimáticas (CAT - catalase; GPX - glutationa peroxidase; GR - glutationa redutase; e GST - Glutationa S-transferase) e não enzimáticas (NP-SH- proteína não-tiol; e TGSH - glutationa total). É apresentada a hipótese de que as ONMs podem causar mudanças na resposta imunológica de peixe e modular o stress oxidativo. Uma dependência do período de exposição foi observada para as ONMs isoladas e também uma sucessão de impactos sobre as fagocitoses da Anguilla Anguilla. A exposição isolada às ONMs parece poder induzir uma resposta aguda em termos de aumento de viabilidade em P-fagócitos e uma atividade fagocítica modulada em P e S-fagócitos após 2 horas de exposição; as ONMs podem induzir imunotoxicidade crónica durante uma exposição de 72 horas, apenas em S-fagócitos. A coexposição a ONM+Hg induziu uma resposta aguda e crónica em termos de atividade fagocítica modulada, com nenhuma mudança na viabilidade em P, HK e S-fagócitos. O aumento do período de exposição a Hg interrompeu a atividade fagocítica de P-, HK - e S-fagócitos. Porém, um aumento de P - e diminuição de HK - e S-fagócitos foi percetível nas 72 horas. A ocorrência de sinergismo entre as ONMs e o Hg foi evidenciado às 72 horas pela tendência do aumento significativo das fagocitoses. Diferença nas induções de OBA e LPO para diferentes períodos de exposição, às ONMs, Hg e ONMs+Hg foi também percetível. Uma indução de OBA paralela à resposta do LPO foi observada unicamente nas guelras por exposição ao Hg (8 e 48 horas) e ONMs+Hg (8 horas). Para períodos mais longos de exposição, foi observada uma indução nas G-fagócitos (OBA) depois da exposição a ONMs+Hg, sugerindo que a contaminação ONMs+Hg é capaz de mitigar os impactos negativos do Hg-acumulado ao longo do tempo. A. Anguilla evidenciou danos ao nível da modulação diferencial de antioxidantes enzimáticos e não enzimáticos em P, G, HK e S-fagócitos. Sob exposição simples às ONMs, não foi observada nenhuma indução do LPO ao longo do tempo, talvez devido à indução eficiente de GR e GST, proporcionando uma melhor proteção para os fagócitos expostos às ONMs. No entanto, as respostas de proteção dos antioxidantes exibiram dependência das horas de exposição em G - e S-fagócitos onde uma insuficiência elevada em CAT, GPX, GST, NP-SH e TGSH foi claramente observada para a manutenção do equilíbrio antioxidante e eliminação de ROS, protegendo os lipídios da membrana contra o impacto das ONMs. A ação conjunta das ONM+Hg conduziu a elevados danos nos lipídios da membrana às 4 e 8 horas (G-fagócitos), 2 horas (HK-fagócitos) e 24 horas (SP-fagócitos) de exposição. Estas respostas conjuntas, apontam para o fracasso da defesa dos antioxidantes na proteção dos lipídios da membrana durante os períodos de exposição com ONM+Hg. De salientar que para exposições de 72 horas, os resultados evidenciam efeitos positivos da exposição concomitante a ONM+Hg o que atenuou impactos negativos do Hg. As observações deste estudo dão novas ideias sobre a avaliação dos mecanismos de defesa imunotoxicológica em peixes expostos a ONMs e indicam que as interações entre ONMs e outros contaminantes antropogénicos devem ser consideradas na interpretação das respostas imunotóxicas de peixe expostos às ONMs em situações contaminação múltipla

Social impact bond feasability study: art as a tool against social exclusion projecto darte

Inequality in education contributes to social exclusion. Students with social, emotional, and behavioral issues tend to face segregation in school and poor educational achievements, which undermine their ability to fulfill their potential. Several sources show that poor performance in school is one of the causes of social exclusion. DARTE successfully uses art as therapy to improve students’ social and learning skills and emotional wellbeing. This feasibility study gives recommendations for the design and implementation of a DARTE SIB in Porto, showing the project as a suitable candidate with the potential to create social and economic benefits

Merchant groups in the 17th-century Brazilian sugar trade! Reappraising old topics with new research insights

This paper examines the role of the New Christians within Portuguese mercantile organizations during the early modern period. It stems from the case of the General Brazil Company, because the foundation of this enterprise provides an example of how the 17th-century Portuguese authorities dealt with New Christian issues, allowing for a survey of Portuguese historiography on the subject

Fiscal innovations in early modern states: which war did really matter in the portuguese case?

Throughout the Early Modern times, European dynastic states started a long-term process towards the building of a territorial organization, depending on increasing revenues and creating its own self-sustaining logics. Different solutions were found to face expenditures; hence different paths to fiscal efficiency came up. This paper brings up the Portuguese case to add new issues to the debate of the factors for fiscal innovation and political-military efficiency in Early Modern times. Prior to the Spanish Secession war, the Portuguese state had faced the Spanish armies in the 14th century and again in the 17th century. Both wars triggered fiscal innovations, shaping the Portuguese fiscal system for centuries afterwards. Taking as benchmarks 1580 and 1680, this paper questions the choice for an income tax precisely at a time when excises were being generalized in North-western Europe. It makes an assessment of state revenues and of the role of this income tax (décima) on a comparative approach. The endurance of décima, as had happened to medieval excises, will be questioned taking into account cost-benefit considerations, regarding the costs (economic and political issues) of any change in collection and assessment. It will be argued that there are good examples of fiscal innovation in the Portuguese case. However, the importance of fiscal innovation for the process of state making and financial modernization may be overestimated just where institutional rigidities had subverted its potentials

Portuguese resilience in global war: military motivation and institutional adaptation in the sixteenth-and seventeenth- century Cape Route

Between 1500 and 1600, intercontinental trade might have grown at an annual compound rate of 1.2 per cent.1 While some enterprises pursued trade through peaceful intercourse, the expansion of global trade was also attained through conflict, violence and recourse to arms, particularly in Euro-Asian trade. Artillery on board merchant vessels was clear evidence that trade and plunder occurred together. Not only was commercial exchange compatible with violence and conflict, but trade ties also prompted far-reaching innovation and adaptation to ensure that commercial ventures remained lucrative. The economic implications of risk of attack or confrontations with opponents led Frederic C. Lane to examine the economic spin-offs of war in protection rents, while Douglass C. North surveyed the consequences of the state’s supply of defence to merchant fleets in his pioneering article on factors for productivity growth in merchant shipping.2 This chapter examines the dynamic between trade and war by explaining how the military competition between Portugal under Habsburg rule (1580–1640) and the Netherlands provoked institutional innovation affecting the financing of commercial voyages to Asia, such that the Portuguese Carreira da Índia continued to be profitable even when confronted with determined rivals and falling pepper prices in European markets..info:eu-repo/semantics/publishedVersio

State monopoly or corporate business : warfare in early-modern Europe

The shift of the core of Europe from the Mediterranean to the north-west of the continent has been considered the outcome of military advantages which, in turn, mirror the early modernisation of the fiscal systems and constitutions of the northern European states. Bearing this in mind, the Portuguese regaining of Brazil from the Dutch, while they were fighting a war against the Habsburgs to regain political independence, is an intriguing issue which leads us to reconsider the widely-accepted connection between the outcomes of military campaigns and modernisation in financial and institutional spheres. In this paper, special attention is paid to the issue of how private and public affairs could intertwine in forming a state. An enlightened estimate of the rates of return from tax farming is provided, as well as proof that uncertainty caused by war raised profits if the commercial integration of trade and the collection of taxes levied on traded commodities was the rule. The accumulation of capital by private tax-collectors was eventually exploited by the state to regain Brazil from the Dutch by means of a compromise which privatised war in the colony. It is argued that the Portuguese solution as far as warfare was concerned was an efficient response to the colonial issue, albeit a divergence from the modern institutional limit between private and public affairs, which gives the state the monopoly over attack (or over defence).info:eu-repo/semantics/publishedVersio

Effect of nostalgia triggered by sound: from the sound of the sea dish: on flavour perception

Nas duas últimas décadas a área da gastronomia tem vindo a ser alvo de constante mudança, os profissionais de artes culinárias têm vindo a explorar cada vez mais na alta cozinha, não só a ciência no ato de cozinhar como as reações fisiológicas do corpo durante uma experiência gastronómica. É comum confundir termos como sabor e flavor, o primeiro diz respeito a uma perceção que se dá exclusivamente na boca enquanto o segundo é a junção de vários sentidos e sensações como sabor, cheiro, tato, audição, visão, emoção, memória, entre outros. Flavor combina todos os estímulos no cérebro de um modo único para o ser humano e este fenómeno tem a designação de perceção multissensorial. Enquanto profissional da área de artes culinárias, a importância de uma formação on the job de qualidade é significativa. Assim sendo foi realizado um estágio na Cozinha Experimental do restaurante The Fat Duck com o objetivo de aplicar e adquirir novos conhecimentos e também de efetuar um estudo experimental preliminar de modo a entender qual “O Efeito da Nostalgia Ativada pelo Som – do Prato Sound of the Sea – na Perceção do Gosto”. O restaurante The Fat Duck dispôs de todo o material necessário tanto para um correto estudo experimental como estágio, o que permitiu: (i) compreender como um restaurante de alta cozinha aplica a ciência no ramo profissional; (ii) aprender novas técnicas; (iii) consolidar e aplicar o conhecimento adquirido durante o Mestrado em Inovação em Artes Culinárias. Os resultados do estudo sugerem que através do som é possível ativar um sentimento de nostalgia. Ao passar o som que simula o mar, fez com que os provadores sentissem o prato Sound of the Sea mais salgado, mais fresco e delicioso do que quando degustado sem o estímulo do som. Os resultados sugerem também que: a) o tipo de memória afeta a aceitação ao prato b) quantos mais sentidos forem ativados durante a perceção multissensorial maior a aceitação; c) cada individuo experiencia a sua própria realidade de perceção multissensorial.The world of gastronomy has significantly changed in the last two decades – professional chefs have been exploring, in the modernist cuisine field, not only the science behind cooking but the physiological reactions one experiences while eating. People are often confused with the terms taste and flavour, while the first is related to what happens exclusively in the mouth, the second regards to a series of sensations – such as taste, smell, touch, sound, sight, emotion, memory and others – processed together in the brain in a way unique to humans. This is known as the multisensory perception experience of eating. As a professional chef, the benefits of on the job training are plenty, therefore an internship at the Fat Duck Experimental Kitchen was accomplished. It was agreed a tasting assay regarding the “Effect of Nostalgia Triggered by Sound – from the Sound of the Sea Dish – on Flavour Perception”, would be conducted during the internship. The Fat Duck restaurant provided with all the materials needed for both the tasting assay and the internship, which allowed to: (i) understand how a fine dining restaurant applies science in the kitchen; (ii) learn new techniques; (iii) reinforce knowledge gathered during the Master’s degree in Innovation in Culinary Arts and Sciences. The tasting assay – which had a preliminary approach – suggested that nostalgia can effectively be triggered by sound. When hearing the sound of the seaside participants felt the Sound of the Sea saltier, fresher and more delicious overall than when sound was not being played. It also suggested that: a) the type of memory evoked, directly affects the enjoyment of the dish; b) the more senses are activated in the multisensory integration the better the overall enjoyment is; c) each individual lives in his own multisensory perception reality

The impact of naturalness on affective response to logo design: A cross-national study

Literature concerned with logo strategy suggests that the aesthetic appeal of brand logos significantly influences consumer responses. Yet, despite the fact that companies invest significant amounts of time and money promoting, updating and changing their logos, empirical studies of logo design issues are rare. In particular, there is little systematic research on the effect of logo design across different cultures. The main purpose of this research is to address the communalities and asymmetries between consumer responses to logo design across cultures. In particular, we focus on the influences of different types of natural designs on consumers’ affective responses in three different countries, Portugal, Spain and The Netherlands. Findings should provide relevant contributions for multinational companies since logos are critical brand identity sings and they tend to be used in an unaltered form in new markets

Design, personality traits and consumer responses to brand logos

Despite the relevance of logos as communication cues, empirical studies of logo design issues in marketing journals are still scarce (Peterson et al., 2015). This study seeks to address this research gap by examining consumers’ responses to logo design, and specifically to the different types of natural designs, at a behavioral and psychological level. Additionally, we explore whether socio-demographic variables and consumer personality traits are sources of differences in such reactions

The chronic food deficit of early modern Portugal : curse or myth?

The chronic food deficit of early modern Portugal: curse or myth? Two historiographie currents have debated whether early modern Portugal was cursed by an excessive dependence on agricultural imports due to being unable to feed its population. In this short paper, the first long-run systematic quantitative study of this question, we show that the former view is a myth and therefore could not be a curse. Throughout the entire period, a certain amount of grain was in fact imported but cereal purchases abroad never represented more than a diminutive percentage of total food consumption. More importantly, the country carried out a diversified trade in foodstuffs which was seldom seriously out of balance. Portuguese agriculture showed itself consistently capable of specializing in different foodstuffs for export. It was thus not hopelessly inefficient and succeeded reasonably well in meeting the basic nutritional needs of the population.info:eu-repo/semantics/publishedVersio