Staphylococci isolated from caprine and ovine mastitic milk: virulence factors and antimicrobial and antibiofilm effectiveness of propolis extracts

Small ruminant mastitis is a major problem for milk producers and consumers causing economic losses and public health threats. This disease is mainly caused by Staphylococcus. The aim of this work was to study propolis for the control of small ruminant mastitis as an alternative to conventional antimicrobials. A total of 137 Staphylococcus belonging to 13 species, recovered from the milk of goats and sheep, were studied. Phenotypic biofilm production and antimicrobial susceptibility were examined. Genes coding for virulence factors were studied: coa, nuc, bap, icaA, icaD, blaZ, mecA, mecC, tetK and tetM. Propolis is a resinous substance produced by honeybees which has been used as a natural medicine for its antiseptic, antimicrobial, antioxidant, anti-inflammatory, and other immunomodulatory properties. Propolis ethanol extracts (PEE) were prepared using different propolis from both Brazil and Portugal. These PEE were chemically characterised and their antimicrobial and antibiofilm activities were assessed. Results showed an association between biofilm production and mastitis inflammatory response. Beta-lactam resistance was mainly detected and an association between animal species and resistance to some antibiotics was found. All isolates were susceptible to gentamicin and cefazolin. The nuc gene was detected in several coagulase negative staphylococci, highlighting its inadequacy for S. aureus identification. Regarding the use of propolis for mastitis control, most PEE showed inhibitory activity against all staphylococci isolates. Furthermore, PEE are bactericidal, which is a very important feature of propolis. Moreover, PEE are effective in inhibiting biofilm formation and in destroying the formed biofilm. The presence of individual phenolics enhanced bactericidal activity, whereas triterpenes negatively influenced both antimicrobial and antibiofilm activity. The results of the present study suggest that propolis should be considered for the control of small ruminant mastitis caused by staphylococci. Nevertheless, future studies are needed to identify the individual propolis compounds exhibiting both antimicrobial and antibiofilm activity; Resumo: A mastite dos pequenos ruminantes é um problema para os produtores e consumidores de leite, causando perdas económicas e ameaças à saúde pública. Esta doença é principalmente causada por Staphylococcus. O objetivo deste trabalho foi estudar a própolis para o controlo da mastite dos pequenos ruminantes como alternativa aos antimicrobianos. Estudaram-se 137 Staphylococcus de 13 espécies, isolados do leite de cabras e ovelhas. Avaliou-se a produção de biofilme e a suscetibilidade aos antimicrobianos. Analisaram-se alguns genes de virulência: coa, nuc, bap, icaA, icaD, blaZ, mecA, mecC, tetK e tetM. A própolis é uma substância resinosa, produzida por abelhas, utilizada como medicamento natural pelas suas propriedades antissépticas, antimicrobianas, antioxidantes, anti-inflamatórias, entre outras. Os extratos etanólicos de própolis (PEE) foram preparados com diferentes própolis do Brasil e de Portugal. Estes PEE foram caraterizados quimicamente e as suas atividades antimicrobiana e antibiofilme avaliadas. Existe uma associação entre a produção de biofilme e a resposta inflamatória à mastite. A resistência aos beta-lactâmicos foi a mais frequente e encontrou-se uma associação entre espécie animal e resistência a alguns antimicrobianos. Todos os isolados foram suscetíveis à gentamicina e à cefazolina. O gene nuc foi detetado em estafilococos coagulase-negativos, mostrando-se inadequado para a identificação de S. aureus. Quanto ao uso de própolis no controlo da mastite, a maioria dos PEE mostrou atividade inibitória contra todos os estafilococos. Além disso, os PEE são bactericidas, uma importante característica do própolis. Adicionalmente, os PEE inibem eficazmente a formação e destroem o biofilme formado. A presença de determinados fenóis aumenta a atividade bactericida, enquanto que os triterpenos influenciam negativamente as atividades antimicrobiana e antibiofilme. Os resultados obtidos sugerem que a própolis seja usada no controlo da mastite de pequenos ruminantes causada por estafilococos. No entanto, são necessários mais estudos para identificar individualmente os compostos do própolis com atividade antimicrobiana e antibiofilme

The articulation of massmedia and social media: exploring civic movements in Portugal

Each time a new communication medium is introduced and reaches relative generalization, it creates new balances and articulations among the existing media, thus reconfiguring the whole mediatic and communicational landscape (Bolter and Grusin, 2000; Jenkins, 2006). In contemporary society, two types of media with totally different characteristics and operating logics coexist, articulate and converge among themselves – massmedia and social media – resulting in a new way of communicating, describes by Manuel Castells (2009) as mass-self communication. Within public relations, several authors recognize a transition from asymmetric communication theories and models, in which organizations publicize information a strongly control their messages, to more symmetric conversation and dialogic models that are emerging as a consequence of PR professionals using social media as communication channels and tools (Kunsch, 2003; Solis and Breakenridge, 2009; Scott, 2010; Macnamara and Zerfass, 2012). Although most of these authors highlight the loss of control over their messages that organizations are undergoing, others explore the emergence of new power balances that are not necessarily symmetric or equalitarian (Edwards and Hodges, 2001; Coombs and Holladay, 2012; Dutta, Ban and Pal, 2012). This paper explores civic movements as an example of the new articulations among massmedia and social media that emerging, as well as new power balances between the public, media and politic agendas (McCombs and Shaw, 1972). Using qualitative methods, this paper empirically explores the recent civic movements against austerity in Portugal, that culminated with the demonstrations “Geração à Rasca” [‘Precarious’ Generation] (12th March 2011) and “Que se lixe a Troika!: Queremos as nossas vidas” [Screw Troika! We want our lives back] (15th September 2012), discussing the articulation of massmedia and social media that was done both by citizens and communication professionals (PRs and journalists, as well the role played by each of these types of media in publicizing, mobilizing and in the social impact of these movements

Travel of studies: cities of João Pessoa, Maceio, Natal and Recife: a look on the urban space and brazilian architectural production

Ponencia presentada a Session 8: Dimensiones psicosociales de la arquitectura y el urbanismo / Psycological dimensions of architecture and planningThis article aims to present the methodology and the final results of the elective course “Travel of Studies” which belongs to the new pedagogical project from the Architecture and Urbanism course at the University Federal of Pernambuco. It was offered for the first time in 2013.The discipline was organized to occur in four long weekends through visits of four capitals of the Northeast of Brazil: Recife, João Pessoa, Natal and Maceió. The purpose was to allow the students to apprehend the cities through four axis: intervention in historical center (axis 1), production of urban space (axis 2), production of coastline space (axis 3) and contemporary architecture (axis 4). After the four visits were complete, we prepared a poster with the comparison of the cities based on the identification of the similarities and differences of each axis we have studied

Numerical methods to predict human induced vibrations on low frequency stairs. Part 2: evaluation by comparing with experimental data

Nowadays, vibration serviceability criteria are becoming the governing factor in the design of most modern staircases, because their increasing susceptibility to human induced vibrations. Although more awareness have been raised to the dynamic design of new staircases, there are still few studies found in the literature that compare the different results of numerical methods for predicting vibrations with experimental data, in order to validate the same. Hence, this paper employs the main existing numerical methods to an actual staircase with known liveness, by comparing the predicted results with the experimental data, to evaluate their accuracy when designing flexible staircases. This paper is Part 2 of a set of two papers. In Part 1, the different numerical methods are presented and details are given of how to apply them. To accomplish this, an in-situ staircase dynamic characterisation and several walking tests are performed. The measured vibrations are initially compared with different proposed acceptable limits to confirm that the vi brations exceed the limits. The different numerical methods are then employed and the predicted results are compared with the experimental results. Lastly, the main findings of this work are discussed together with those of diverse researchers who also applied one of these procedures to estimate vibrations. The results obtained showed that, with two of the numerical procedures applied (footfall force time histories and simplified vibration evaluation), it was possible to effectively predict the vibrations, while with the remaining two (Fourier series walking models and steady-state analysis), in general, overestimated responses were predicted.info:eu-repo/semantics/publishedVersio

Pre-design of laterally supported stair steps

It is becoming increasingly common to design monumental staircases and their steps with elevated stiffness and low mass, obtaining high natural frequencies, off the range of frequencies that are excitable by pedestrians. However, this sometimes leads to unacceptable levels of vibration, with impulsive responses. In many cases the dynamic behaviour of steps is almost independent from the rest of the staircase, causing a phenomenon de signated as local vibrations, which could be much more severe than the global vibrations of the staircase. In order to avoid this problem, this paper presents a simplified expression to pre-design stair steps which guarantee that excessive vibrations will not occur, without the need to perform a dynamic analysis. The ex pression was deduced based on the results of an experimental campaign, several numerical analyses and a theoretical analysis. During this study it was necessary to define an acceptable limit of vibrations specific for this type of vibration, which affects mainly the feet of pedestrians. The expression deduced is easy to apply because it depends only of vertical stiffness of the step. Finally, the pre-design expression is also applied to the staircase used in the experimental campaign, and it was concluded that it would be easy to avoid excessive vibrations, with a negligible cost increase.info:eu-repo/semantics/publishedVersio

Application of the effective impulse approach to stairs

One of the most commonly used simplified methods for predicting man induced vibrations in floors with high fundamental frequencies is the Effective Impulsive approach, first developed by the ARUP's company and later modified by the design guide SCI P354. Since the Effective Impulse approach was designed to be used in floors, its use in stairs can be arguable. To better understand the effectiveness of this method in stairs, in this paper are experimentally measured vibrations on a staircase with a poor dynamic behavior and then compared to the vibrations predicted using the Effective Impulse approach. The results indicate that this approach can be used, especially in the stair descends. The serviceability of the analyzed staircase was also verified by comparing the measured and predicted vibrations with the acceptable limits proposed by various authors and design guides.info:eu-repo/semantics/publishedVersio

Phlorotannin Extracts from Fucales Characterized by HPLC-DAD-ESI-MSn: Approaches to Hyaluronidase Inhibitory Capacity and Antioxidant Properties

Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn . Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC50 = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC50 = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC50 = 0.93 mg/mL dry weight), followed by F. spiralis (IC50 = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process.info:eu-repo/semantics/publishedVersio

Concepciones docentes sobre el constructivismo y su implantación en la red estatal de enseñanza primaria

No presente relato de pesquisa, são apresentadas as concepções dos professores sobre o construtivismo, investigadas através de entrevista com quarenta professores do ensino fundamental de duas escolas de uma cidade do interior de São Paulo. As entrevistas foram gravadas e transcritas literalmente, e os resultados foram submetidos à Análise de Conteúdo. As entrevistas indicaram que a maioria dos professores tem uma noção imprecisa sobre o construtivismo. Os professores consideraram que, devido à falta de estudo, orientação e apoio da escola, não têm preparo para trabalharem com o construtivismo. Dessa forma, supõe-se que os pressupostos construtivistas não foram transmitidos de maneira adequada aos docentes. Constatou-se que, para os professores, o construtivismo foi mais uma reforma educacional imposta a eles. De maneira geral, os professores não são desfavoráveis à implantação do construtivismo no cotidiano escolar, porém não concordam com a forma como se deu essa implantação.In this study we investigate teachers’ conceptions of constructivism. We interviewed forty teachers from two elementary schools in the countryside of the state of São Paulo. The interviews were tape-recorded and transcribed literally. Content Analysis was used to analyze the data. The results indicated that most teachers have an imprecise notion of Constructivism. The teachers considered that, due to the lack of study, guidance and support from the school, they are unprepared to adopt constructivist pedagogy. Thus, it is possible to suggest that the constructivist presuppositions have been transmitted to teachers through an inadequate strategy. For these professionals, Constructivism seems to represent one more educational reform which was imposed on them. In general, the teachers revealed to be favorable to the implementation of Constructivism in their classrooms. However they disagree with the way it has been implemented.En el presente relato de investigación son presentadas las concepciones de los profesores sobre el constructivismo, investigadas a través de entrevista con cuarenta profesores de la enseñanza primaria de dos escuelas de una ciudad del interior de São Paulo. Las entrevistas fueron grabadas y transcritas literalmente y los resultados fueron sometidos a Análisis de Contenido. Las entrevistas indicaron que la mayoría de los profesores tiene una noción imprecisa sobre el constructivismo. Los profesores consideraron que, debido a la falta de estudio, orientación y apoyo de la escuela, ellos no tienen preparo para trabajar con el constructivismo. De esta forma, se supone que los postulados constructivistas no fueron transmitidos de manera adecuada para los profesores. Se constató que, para los profesores, el constructivismo fue una reforma educativa más a ellos impuesta. En general, los profesores no son desfavorables a la implementación del constructivismo en el cotidiano escolar, sin embargo no están de acuerdo con la forma de cómo se realizó esa implantación.FAPES

Rethinking Digital Games in a Critical and Participatory Perspectives. A Brief Reflection

Digital games are social objects created based on our culture and society and at the same time they contribute to shaping our world. Through a critical perspective of digital games and technology, it is possible to discuss the unfolding of these artefacts in our society and also understand their relevance beyond an instrumental view. In this paper, we present a brief reflection based on two researches developed by the authors: the first, regarding the link between digital games and people with disabilities; and the second, about contributions of digital games to a critical education. Our goal with this work is to highlight the emancipatory and participatory potential present in the critical vision of digital games