Aline de Oliveira

Discovery and Characterization of Alamandine, a Novel Component of the Renin-Angiotensin System

Rationale: The renin–angiotensin system (RAS) is a key regulator of the cardiovascular system, electrolyte, and water balance. Here, we report identification and characterization of alamandine, a new heptapeptide generated by catalytic action of angiotensin-converting enzyme-2 angiotensin A or directly from angiotensin-(1–7). Objective: To characterize a novel component of the RAS, alamandine. Methods and Results: Using mass spectrometry we observed that alamandine circulates in human blood and can be formed from angiotensin-(1–7) in the heart. Alamandine produces several physiological actions that resemble those produced by angiotensin-(1–7), including vasodilation, antifibrosis, antihypertensive, and central effects. Interestingly, our data reveal that its actions are independent of the known vasodilator receptors of the RAS, Mas, and angiotensin II type 2 receptor. Rather, we demonstrate that alamandine acts through the Mas-related G-protein–coupled receptor, member D. Binding of alamandine to Mas-related G-protein–coupled receptor, member D is blocked by D-Pro7-angiotensin-(1–7), the Mas-related G-protein–coupled receptor, member D ligand β-alanine and PD123319, but not by the Mas antagonist A-779. In addition, oral administration of an inclusion compound of alamandine/β-hydroxypropyl cyclodextrin produced a long-term antihypertensive effect in spontaneously hypertensive rats and antifibrotic effects in isoproterenol-treated rats. Alamandine had no noticeable proliferative or antiproliferative effect in human tumoral cell lines. Conclusions: The identification of these 2 novel components of the RAS, alamandine and its receptor, provides new insights for the understanding of the physiological and pathophysiological role of the RAS and may help to develop new therapeutic strategies for treating human cardiovascular diseases and other related disorders. # Novelty and Significance {#article-title-32}Rationale: The renin–angiotensin system (RAS) is a key regulator of the cardiovascular system, electrolyte, and water balance. Here, we report identification and characterization of alamandine, a new heptapeptide generated by catalytic action of angiotensin-converting enzyme-2 angiotensin A or directly from angiotensin-(1–7). Objective: To characterize a novel component of the RAS, alamandine. Methods and Results: Using mass spectrometry we observed that alamandine circulates in human blood and can be formed from angiotensin-(1–7) in the heart. Alamandine produces several physiological actions that resemble those produced by angiotensin-(1–7), including vasodilation, antifibrosis, antihypertensive, and central effects. Interestingly, our data reveal that its actions are independent of the known vasodilator receptors of the RAS, Mas, and angiotensin II type 2 receptor. Rather, we demonstrate that alamandine acts through the Mas-related G-protein–coupled receptor, member D. Binding of alamandine to Mas-related G-protein–coupled receptor, member D is blocked by D-Pro7-angiotensin-(1–7), the Mas-related G-protein–coupled receptor, member D ligand &bgr;-alanine and PD123319, but not by the Mas antagonist A-779. In addition, oral administration of an inclusion compound of alamandine/&bgr;-hydroxypropyl cyclodextrin produced a long-term antihypertensive effect in spontaneously hypertensive rats and antifibrotic effects in isoproterenol-treated rats. Alamandine had no noticeable proliferative or antiproliferative effect in human tumoral cell lines. Conclusions: The identification of these 2 novel components of the RAS, alamandine and its receptor, provides new insights for the understanding of the physiological and pathophysiological role of the RAS and may help to develop new therapeutic strategies for treating human cardiovascular diseases and other related disorders.

The redox processes in Hg-contaminated soils from Descoberto (Minas Gerais, Brazil): implications for the mercury cycle.

Investigations of the redox process and chemical speciation of Hg(II) lead to a better understanding of biogeochemical processes controlling the transformation of Hg(II) into toxic and bioaccumulative monomethyl mercury, mainly in areas contaminated with Hg(0). This study investigates the speciation and redox processes of Hg in soil samples from a small area contaminated with Hg(0) as a result of gold mining activities in the rural municipality of Descoberto (Minas Gerais, Brazil). Soil samples were prepared by adding Hg(0) and HgCl2 separately to dry soil, and the Hg redox process was monitored using thermodesorption coupled to atomic absorption spectrometry. A portion of the Hg(0) added was volatilized (up to 37.4±2.0%) or oxidized (from 36±7% to 88±16%). A correlation with Mn suggests that this oxidation is favored, but many other factors must be evaluated, such as the presence of microorganisms and the types of organic matter present. The interaction of Hg with the matrix is suggested to involve Hg(II)-complexes formed with inorganic and organic sulfur ligands and/or nonspecific adsorption onto oxides of Fe, Al and/or Mn. The kinetics of the oxidation reaction was approximated for two first-order reactions; the faster reaction was attributed to the oxidation of Hg(0)/Hg(I), and the slower reaction corresponded to Hg(I)/Hg(II). The second stage was 43-139 times slower than the first. The samples spiked with Hg(II) showed low volatilization and a shifting of the signal of Hg(II) to lower temperatures. These results show that the extent, rate and type of redox process can be adverse in soils. Descoberto can serve as an example for areas contaminated with Hg(0).

Effects of Iron Enrichment of Adzuki Bean (Vigna angularis) Sprouts on Elemental Translocation, Concentrations of Proteins, Distribution of Fe-Metalloproteins, and Fe Bioaccessibility

Iron (Fe) is an essential element for human nutrition, and its deficiency or low hemoglobin levels are a global health issue. Strategies aimed at increasing the amounts of essential elementals in agricultural products, as sprouts of adzuki bean (Vigna angularis), can be a way to minimize deficiencies, mainly in the populations of developing countries. Therefore, in this work was evaluated: production of Fe-enriched adzuki bean sprouts; Fe accumulation and translocation in plants in different culture media enriched with different Fe masses (500, 1000, 2000, and 3000 μg); and effects of the enrichment by means of 3000 μg Fe-ethylenediaminetetraacetic acid (Fe-EDTA): on the distribution of Ca, Cu, Fe, K, P, Mg, S, and Zn in different parts of the plant; on protein concentrations (albumins, globulins, prolamins, and glutelins) and their association with Fe in edible parts of the plant (stems); and on Fe bioaccessibility in the edible part of the plant (stems). The enrichment via Fe-EDTA favored the translocation and increased Fe content of sprouts (75%), besides promoting interactions of Fe with albumins (141%), globulins (180%), and glutelins (93%). In the bioaccessibility assays, Fe was 83% bioaccessible in Fe-enriched sprouts.

A Validated NMR Approach for MDMA Quantification in Ecstasy Tablets

In recent years, ecstasy trafficking has grown in complexity and tablets has been commonly sold containing different contents of 3,4-methylenedioxymethamphetamine (MDMA) or even other psychoactive substances. In contrast, identification and quantification of drugs of abuse is still a challenge, once the access to drug standards is very restricted in Brazil. In this work, ecstasy tablets seized by the Brazilian Federal Police have their chemical composition identified and quantified by gas chromatography and quantitative 1H nuclear magnetic resonance based on an internal standard approach (IS-1H-qNMR). Both methods were validated and showed suitable results for the figures of merit. IS-1H-qNMR shows excellent results of accuracy (relative error < 5%) and precision (relative standard deviation (RSD) < 2%). Comparatively, IS-1H-qNMR is more efficient and versatile than gas chromatography to accomplish in a single analysis the identification and quantification of target analytes. Since the method does not require a specific reference material, it is cost effective and provides agility to routine forensic analysis.

Natural Organic Acid as Green Catalyst for Xanthenones Synthesis: Methodology, Mechanism and Calcium Channel Blocking Activity

Xanthenones were synthesized via one-pot tricomponent reaction, under solvent-free conditions, using aldehydes, phenolic and cyclic 1,3-dicarbonyl compounds. Natural organic acids (NOAs), compounds present in many living metabolisms, were used as potential green catalysts. NOA are considered to be more eco-friendly and user-friendly alternative to traditional methodologies. Optimization studies showed that oxalic acid was the best NOA catalyst for such reaction furnishing the xanthenones with up to 93% of yield. Theoretical calculations were performed to evaluate this reaction mechanism and regioselectivity. The results showed that the regiospecificity of this three-component reaction is kinetically and thermodynamically controlled by the addition of b-naphthol C2, instead of C10, to the aldehyde. Our results also disclosed two xanthenones as novel calcium channels blockers. Eco-friendly reaction conditions, easy workup procedure, short reaction times and good yields are some of the advantages of our methodology.

A Rainha do Ignoto, de Emília Freitas: do fantástico à utopia

A literatura fantastica desenvolvida entre fins do seculo XVIII e fins do seculo XIX, fruto das tensoes entre o espirito racionalista do Iluminismo e o renascimento do irracional impulsionado por correntes misticas e ocultistas do pensamento, foi pouco aberta a protagonistas femininas: de fato, em geral, a mulher aparece, em tais narrativas, como espectro do mal, cumplice de Sata, mensageira da ameaca a estabilidade do homem e do real. Em A Rainha do Ignoto , de Emilia Freitas, publicado originalmente em 1899, assistimos a uma reversao do papel comumente destinado as personagens femininas em narrativas nao realistas do seculo XIX: de mensageiras do mal, elas passam a agentes do bem, atuando na intersecao entre magia e tecnica. Tal deslocamento na representacao da figura feminina esta atrelado a um deslocamento na propria narrativa – do fantastico a utopia –, o que conduz a reflexao sobre a relacao entre generos literarios e representacoes do feminino e, em ultima instância, sobre a utopia como forma de resistencia frente ao apagamento ou a demonizacao da mulher em narrativas nao realistas.

Notas sobre a teoria estruturalista do gênero fantástico de Tzvetan Todorov

Tzvetan Todorov, um dos principais nomes do estruturalismo frances, publicou, em 1970,a seminal Introducao a literatura fantastica, obra de folego que ainda hoje goza de grandeprestigio nos estudos dedicados a literatura fantastica produzida na Europa entre osseculos 18 e 19. Ainda que o livro tenha sido lancado apos a crise do paradigmaestruturalista, o modelo proposto por Todorov para a narrativa fantastica segue, demodo geral, os pressupostos de um uma an|lise estrutural mais “ortodoxa”: sua tarefaconsiste em elaborar um modelo global de analise do genero fantastico, definindo-orelativamente aos seus generos vizinhos, o estranho e o maravilhoso, e trabalhando naimanencia do texto liter|rio. Alem disso, s~o valorizados o metodo “cientifico” e adefinicao de categorias e regras para a realizacao do fantastico. Hoje, 40 anos depois deseu lancamento, quando tanto o estruturalismo quanto o chamado pos-estruturalismo janao constituem mais o paradigma teorico nos estudos literarios, cabe retornar a esselivro, analisando seus pressupostos, suas contribuicoes para o estudo do fantastico e suaslimitacoes, para, enfim, refletir sobre as implicacoes de se tentar forjar uma teoriatotalizadora do fantastico.