The interactive effects of microcystin-LR and cylindrospermopsin on the growth rate of the freshwater algae Chlorella vulgaris

Microcystin-LR (MC-LR) and cylindrospermopsin (CYN) are the most representative cyanobacterial cyanotoxins. They have been simultaneously detected in aquatic systems, but their combined ecotoxicological effects to aquatic organisms, especially microalgae, is unknown. In this study, we examined the effects of these cyanotoxins individually and as a binary mixture on the growth rate of the freshwater algae Chlorella vulgaris. Using the MIXTOX tool, the reference model concentration addition (CA) was selected to evaluate the combined effects of MC-LR and CYN on the growth of the freshwater green algae due to its conservative prediction of mixture effect for putative similar or dissimilar acting chemicals. Deviations from the CA model such as synergism/antagonism, dose-ratio and dose-level dependency were also assessed. In single exposures, our results demonstrated that MC-LR and CYN had different impacts on the growth rates of C. vulgaris at the highest tested concentrations, being CYN the most toxic. In the mixture exposure trial, MC-LR and CYN showed a synergistic deviation from the conceptual model CA as the best descriptive model. MC-LR individually was not toxic even at high concentrations (37 mg L(-1)); however, the presence of MC-LR at much lower concentrations (0.4-16.7 mg L(-1)) increased the CYN toxicity. From these results, the combined exposure of MC-LR and CYN should be considered for risk assessment of mixtures as the toxicity may be underestimated when looking only at the single cyanotoxins and not their combination. This study also represents an important step to understand the interactions among MC-LR and CYN detected previously in aquatic systems.info:eu-repo/semantics/publishedVersio

Absence of negative allelopathic effects of cylindrospermopsin and microcystin-LR on selected marine and freshwater phytoplankton species

Cyanobacterial toxins have been regarded by some researchers as allelopathic substances that could modulate the growth of competitors. Nevertheless, often the concentrations of toxins used are too high to be considered ecologically relevant. In this work we tested the hypothesis that microcystin-LR (MC-LR) and cylindrospermopsin (CYN) at ecologically relevant concentrations have no allelopathic effects on some species of phytoplankton. Extracts containing the toxins as well as pure MC-LR and CYN toxins were used to assess their effects on the growth rates of Nannochloropsis sp., Chlamydomonas reinhardtii, and Chlorella vulgaris. Cyanobacterial crude extracts induced more pronounced effects on growth rates than pure toxins. Microcystis aeruginosa and Aphanizomenon ovalisporum crude extracts containing MC-LR and CYN at 0.025–2.5 mg l−1 stimulated growth rates of microalgae, whereas A. ovalisporum crude extracts containing 2.5 mg l−1 of CYN strongly inhibited growth rates of microalgae after 4 and 7 days of exposure. MC-LR and CYN at environmentally occurring concentrations were unable to affect negatively the growth of microalgae, and therefore these molecules may play roles other than allelopathy in natural ecosystems.info:eu-repo/semantics/publishedVersio

CARACTERIZAÇÃO DA MISTURA ÓLEO DE SOJA E GORDURA SUÍNA 1:1 (m m-1) E SEU POTENCIAL NA PRODUÇÃO DE BIODIESEL

O biodiesel no Brasil é obtido, predominantemente, pela reação de transesterificação de óleo de soja por via metílica. Buscando encontrar uma maneira em minimizar a quantidade de óleo de soja usado na produção de biodiesel, o objetivo deste trabalho foi averiguar o potencial da mistura de óleo de soja e gordura suína 1:1 (m m-1) para esse fim, para isso foram determinadas suas propriedades físico-químicas e sua composição por cromatografia gasosa acoplada a detector de chamas (CG-DIC). A referida mistura apresentou umidade, índice de acidez, índice de iodo, massa específica, ponto de fusão, índice de saponificação e composição de ácidos graxos dentro do desejado para matéria-prima na produção de biodiesel, sendo encontrados 20,84% de palmítico, 8,32% de esteárico, 30,55% de oléico, 33,53% de linoléico e 2,39% de linolênico

Effects on growth, antioxidant enzyme activity and levels of extracellular proteins in the green alga Chlorella vulgaris exposed to crude cyanobacterial extracts and pure microcystin and cylindrospermopsin

Toxic cyanobacteria and cyanotoxins have been pointed as important players in the control of phytoplankton diversity and species abundance, causing ecological unbalances and contamination of the environment. In vitro experiments have been undertaken to address the impact of toxic cyanobac- teria in green algae. In this regard the aim of this work was to compare the toxicity of two cyanobacteria species, Aphanizomenon ovalisporum and Microcystis aeruginosa, to the green alga Chlorella vulgaris by assessing culture growth when exposed for three and seven days to (I) cyanobacterial cell extracts and (II) pure toxins microcystin-LR (MC-LR) and cylindrospermopsin (CYN).info:eu-repo/semantics/publishedVersio

Adição de fontes de nitrogênio e duas linhagens de levedura na fermentação alcoólica para produção de cachaça

Neste trabalho foi avaliado a influência de duas linhagens de levedura, baixa fermentação (Saflager) e alta fermentação (Safbrew), três fontes de nitrogênio (sulfato de amônio, peptona de caseína e um pool de aminoácidos, nas concentrações 5 g/L e 25 g/L, e o controle (sem adição de nitrogênio), na cinética de fermentação e na composição da cachaça. Os parâmetros da cinética de fermentação foram: pH, acidez total, teor de sólidos solúveis e o teor alcoólico, em amostras coletadas em 12, 24, 48, 72 e 96 horas de fermentação. A média de concentração final de etanol nos mostos foi de 7,7 ºGL. As amostras de cachaça foram analisadas por cromatografia a gás, sendo que os alcoóis superiores, propan-1-ol, álcool isobutílico e isoamílico tiveram comportamentos diferentes para as linhagens de leveduras de baixa fermentação e alta fermentação. A concentração de 5 g/L das fontes nitrogenadas já foi suficiente para elevar as concentrações  dos alcoóis superiores nas amostras de cachaça. DOI: 244694160101201504

A CONSTRUÇÃO DA DIMENSÃO SIMBÓLICA DA PERSONAGEM MARIA LIONÇA: uma exaltação a terra, a mulher e a mãe

O presente artigo analisa o universo de Miguel Torga e a sua estima pelo homem como um deus na terra, aquele que tem o poder de mudar seu destino e carregar o fardo de sua existência. Atrelado ao seu realismo literário, permaneceu entranhado à visão de mundo do escritor, o retrato do humano e do desumano, sem maiores pretensões, além de mostrar ao homem como ele realmente é. As personagens são colhidas do cotidiano, do mundo rústico das montanhas, extremamente humanas.  A personagem homônima do conto Maria Lionça, da obra  Contos da Montanha, personifica a ruralidade e a dignidade daqueles que, apesar de analfabetos, se impunham pelo respeito, pela sua sabedoria popular empírica, ainda que o destino lhes reservasse uma vida de sofrimento e de habitual resignação à miséria e à desgraça. O conto apresenta um conjunto bem estruturado de elementos que compõem o humano em Miguel Torga. Nesses contos, a terra, a morte e a vida confundem-se, como essências da própria existência do ser humano.  Palavras-chave: Semiologia. Maria Lionça. Presencismo. Personagem.Abstract: This article analyzes the universe of Miguel Torga and their esteem by the man as a god on earth, one that has the power to change his fate and the burden of its existence. Tied to his literary realism remained deep-seated its world view the picture of human and inhuman, no greater pretensions than to show the man as he really is. The characters taken from everyday life, the rural world of the mountains, very human. Thus, for example, the character Maria Lionça, Tales of the work of the Mountain, embodies the rural and dignity of those who, though illiterate, were imposed by respect for their wisdom empirical, although the destination you book a life of suffering and you get used to poverty and disgrace. From the character's name, which already has a symbolic dimension, the analysis extends to the tale, in search of all that makes up the human Miguel Torga: earth, life and death as the essence of his own existence.  Keywords: Semiology. Maria Lionça. Presencismo. Character

Desaturation – distance ratio: a new concept for a functional assessment of interstitial lung diseases

INTRODUCTION: The functional evaluation has become increasingly important in the understanding and management of patients with interstitial lung diseases. The cardiopulmonary exercise test and the six-minute walk test (6MWT), through their isolated variables, have been used to do this evaluation, with some limitations. OBJECTIVES: We proposed a new composite index (desaturation distance ratio using continuous peripheral oxygen saturation (SpO2) and the distance walked as a more reliable tool for doing a functional evaluation of these patients. METHODS: 6MWT was performed by interstitial lung diseases patients and controls. Analyzed parameters were walked distance and desaturation area (DAO2), obtained by taking the difference between maximal SpO2 possible (100%) and patient's SpO2 every 2 seconds. desaturation distance ratio was calculated using the ratio between DAO2 and distance walked. RESULTS: Forty-nine interstitial lung diseases patients and 11 control subjects completed the protocol. The mean (SD) age was 60 (12) years and 65 (9) years, respectively (p:NS). Data obtained from 6MWT showed a significant statistical difference between interstitial lung diseases patients and controls: mean walked distance (430 and 602 meters, respectively); SpO2 minimal maintained at least 10 seconds - SpO2 min (85% and 94%, respectively), and median desaturation distance ratio (10 and 2.5, respectively). A correlation analysis, considering interstitial lung diseases patients, revealed the best correlation between desaturation distance ratio and DLco (r= - 0.72; p<0.001), being the correlation between SpO2 min and DLco of 0.61 (p<0.001) and among walked distance and DLco of 0.58 (p<0.05). CONCLUSION: Desaturation distance ratio is a promising concept and a more reliable physiologic tool to assess pulmonary diseases characterized by involvement of the alveolar-capillary membrane, such as interstitial lung diseases

O Jogo Hermenêutico em Tempos de Gamificação

The present work is immersed in the context of the changes brought about by the insertion and growth of games in society - especially in the field of education - where two important practices complement each other: the hermeneutic game and gamification. Thus, we have as a general objective to relate hermeneutic practice to gamification, specifying in the main concepts related to these models, as well as their phenomena and teaching strategies, taking into account traditional methodologies and the influence of new technologies and media on the formation of the individual. As a conclusion after conducting an exploratory research, it is noted how every day new issues related to the theme of the game with the learning function or teaching method appear, a factor that points to a future of teaching more and more gamificado and dynamic.El presente trabajo se muestra inmerso en el contexto de los cambios provocados por la inserción y crecimiento de los juegos en la sociedad -sobre todo en el campo de la educación- donde dos importantes prácticas se complementan entre sí: el juego hermeneutico y la gamificación. De este modo, tenemos por objetivo general relacionar la práctica hermenéutica con la gamificación, especificándose en los principales conceptos referentes a esos modelos, tal como sus fenómenos y estrategias de enseñanza, teniendo en cuenta las metodologías tradicionales y la influencia de las nuevas tecnologías y medios sobre la formación del individuo. Como conclusión después de realizar una investigación exploratoria, se nota cómo cada día surgen más novedades relacionadas con la temática del juego con la función de aprendizaje o método de enseñanza, factor que apunta hacia un futuro de enseñanza cada vez más gamificado y dinámico.O presente trabalho se mostra imerso no contexto das mudanças provocadas pela inserção e crescimento dos games na sociedade – sobretudo no campo da educação – onde duas importantes práticas complementam-se entre si: o jogo hermeneutico e a gamificação. Desse modo, temos por objetivo geral relacionar a prática hermenêutica com a gamificação, especificando-se nos principais conceitos referentes à esses modelos, tal como seus fenômenos e estratégias de ensino, levando em consideração as metodologias tradicionais e a influência das novas tecnologias e mídias sobre a formação do indivíduo. Como conclusão após realizada uma pesquisa exploratória, nota-se como a cada dia surgem mais novidades relacionadas a temática do jogo com a função de aprendizagem ou método de ensino, fator que aponta para um futuro de ensino cada vez mais gamificado e dinâmico

Prognostic value of the immunohistochemical detection of epithelial-mesenchymal transition biomarkers in oral epithelial dysplasia : a systematic review

Oral potentially malignant disorders (OPMDs) comprise a range of clinical-pathological alterations that are frequently characterized as architectural and cytological derangements upon histological analysis. Epithelial-mesenchymal transition (EMT) has been proposed as a critical mechanism for the acquisition of the malignant phenotype in neoplastic epithelial processes. This study aims to systematically review the current findings on the immunohistochemical expression of epithelial-mesenchymal transition markers in oral potentially malignant disorders and to evaluate their possible application as biomarkers associated with the progression of oral epithelial dysplasias. A systematic search was performed in the following databases: PubMed, EMBASE, Chinese BioMedical Literature Database, and Cochrane Library. Articles that evaluated the relationship between the expression of EMT markers and the degree of oral epithelial dysplasia were selected for the systematic review. The quality of each eligible study was evaluated by independent reviewers that used operationalized prognostic biomarker reporting guidelines (REMARK). Seventeen articles met all inclusion criteria and were selected. The EMT markers analyzed exhibited an important association with the prognosis of the cases evaluated. The results showed a progressive increase in the expression of nuclear transcription factors and markers of mesenchymal differentiation, as well as negative regulation of epithelial and cell adhesion markers, according to the stage of oral epithelial dysplasia. The dysregulation of expression of important EMT components in oral dysplastic epithelium is a potential prognostic marker in OPMDs