Lídia Barata - Academia.edu (original) (raw)

Papers by Lídia Barata

Media education has been the subject of several studies and the theme of various researches and p... more Media education has been the subject of several studies and the theme of various researches and projects, particularly involving children and young people. This focus on media education was intensified since the Declaration of Grundwald (1982), that stands for the introduction of this subject in the curricula of all levels of education, the promotion of teacher training, as well as the strengthen of international cooperation. These recommendations have been repeated until today, however they haven't been implemented yet. Journalism at school is a way to promote media education, if students can understand and are aware of the media products they access, they will easier produce their own. Local press can also promote non-formal education, promoting the activities of schools, publishing the students' media products. This project aims the discussion of this subject through a case study in the district of Castelo Branco. After a theoretical background on the topic media education, we analyze the way local newspapers, with the largest circulation in the district of Castelo Branco, including Reconquista, Gazeta do Interior, Jornal do Fundão and Notícias da Covilhã, deal with the news produced at Primary and Secondary Schools. The main purpose of was to check any variations on the number, type and themes of the news published in local newspapers during the period of the project Educação para os Media no Distrito de Castelo Branco, between 2007-2011, as well as to verify the emphasis given to these media products. In addition, we also looked into the way media education is faced by publishers of local press. It appears that, there was no significant variation in the number, type and theme of the news that were published, the publishers of the four papers agree that the school news that reach their newspapers deserve an analysis and sometimes they are published with prominence. They also recognize that media education is important to develop critical awareness and reading habits amongst young people.

The American journal of tropical medicine and hygiene

$Research paper thumbnail of Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of glyoxalase I from Leishmania infantum$

Acta crystallographica. Section F, Structural biology and crystallization communications, 2010

Glyoxalase I (GLO1) is the first of the two glyoxalase-pathway enzymes. It catalyzes the formatio... more Glyoxalase I (GLO1) is the first of the two glyoxalase-pathway enzymes. It catalyzes the formation of S-D-lactoyltrypanothione from the non-enzymatically formed hemithioacetal of methylglyoxal and reduced trypanothione. In order to understand its substrate binding and catalytic mechanism, GLO1 from Leishmania infantum was cloned, overexpressed in Escherichia coli, purified and crystallized. Two crystal forms were obtained: a cube-shaped form and a rod-shaped form. While the cube-shaped form did not diffract X-rays at all, the rod-shaped form exhibited diffraction to about 2.0 A resolution. The crystals belonged to space group P2(1)2(1)2, with unit-cell parameters a = 130.03, b = 148.51, c = 50.63 A and three dimers of the enzyme per asymmetric unit.

Experimental Parasitology, 2011

Leishmania infantum glyoxalase II shows absolute specificity towards its trypanothione thioester ... more Leishmania infantum glyoxalase II shows absolute specificity towards its trypanothione thioester substrate. In the previous work, we performed a comparative analysis of glyoxalase II structures determined by X-ray crystallography which revealed that Tyr291 and Cys294, absent in the human homologue, are essential for substrate binding. To validate this trypanothione specificity hypothesis we produced a mutant L. infantum GLO2 enzyme by replacing Tyr291 and Cys294 by arginine and lysine, respectively. This new enzyme is capable to use the glutathione thioester substrate, with kinetic parameters similar to the ones from the human enzyme. Substrate specificity is likely to be mediated by spermidine moiety binding, providing a primer for understanding the molecular basis of trypanothione specificity.

Biochemistry, 2008

The glyoxalase pathway catalyzes the formation of d-lactate from methylglyoxal, a toxic byproduct... more The glyoxalase pathway catalyzes the formation of d-lactate from methylglyoxal, a toxic byproduct of glycolysis. In trypanosomatids, trypanothione replaces glutathione in this pathway, making it a potential drug target, since its selective inhibition might increase methylglyoxal concentration in the parasites. Two glyoxalase II structures were solved. One with a bound spermidine molecule (1.8 A) and the other with d-lactate at the active site (1.9 A). The second structure was obtained by crystal soaking with the enzyme substrate (S)-d-lactoyltrypanothione. The overall structure of Leishmania infantum glyoxalase II is very similar to its human counterpart, with important differences at the substrate binding site. The crystal structure of L. infantum glyoxalase II is the first structure of this enzyme from trypanosomatids. The differential specificity of glyoxalase II toward glutathione and trypanothione moieties was revealed by differential substrate binding. Evolutionary analysis shows that trypanosomatid glyoxalases II diverged early from eukaryotic enzymes, being unrelated to prokaryotic proteins.

$Research paper thumbnail of Purification, crystallization and preliminary X-ray diffraction analysis of the glyoxalase II from Leishmania infantum$

Acta Crystallographica Section F Structural Biology and Crystallization Communications, 2006

Acta Crystallographica Section D Biological Crystallography, 2004

$Research paper thumbnail of Purification, crystallization and preliminary X-ray diffraction analysis of the carbohydrate-binding region of the Streptococcus gordonii adhesin GspB$

In a media-saturated world it is crucial to empower children and young people to deal with the me... more In a media-saturated world it is crucial to empower children and young people to deal with the media which means that we have to develop Media Literacy. To do that the society has to prepare them to do critical analysis and reflexive production of media messages both in traditional and new media. Besides that at school it is important to allow the students discuss and choose the topics that they want to talk about. This paper presents results of a Media Education project in Portugal (2008-2011) about school newspapers production. By the end of the project we analyzed all the school newspapers editions and pointed out the preferred topics of the students. The paper also presents three ongoing researches: one about school stories in local newspapers before and after the project; another about what students and teachers talk about in social media and a third one about how students, teachers and parents deal with social media in