DNA and chromosomal damage in Senegalese sole (Solea senegalensis) as side effects of ozone-based water treatment - contribution to optimization of fish-farming practices

The progressive growth of aquaculture implicates a dependence on large water amounts, which are submitted to disinfection processes, namely ozonation. Considering the importance of genomic integrity, it is critical to improve the knowledge on ozone-related genotoxic hazard to organisms reared in recirculating aquaculture systems (RAS) applying ozonation. Therefore, genetic damage induced by ozone exposure in the Senegalese sole (Solea senegalensis) was assessed, combining the comet and the erythrocytic nuclear abnormalities (ENA) assays, reflecting different damage levels, i.e. DNA and chromosomal damage, respectively. Fish were subjected to a daily 6-h ozone (0.15 mg L-1) exposure, repeated for 3 consecutive days, simulating a short-term event of overozonation. To assess the temporal impact of the previous event, the progression of damage was evaluated 7 days later, following transference to ozone-free water or to 0.07 mg L-1 ozone, a routinely adopted level in RAS. Both endpoints pointed to the ozone genotoxic potential, displaying DNA oxidation as a possible mechanism of damage. Overall, the present findings pointed out the genotoxic hazard of ozone to fish, highlighting the importance of these types of studies and contributing to improve aquaculture practices, namely in RAS systems. These early genotoxic signals may be a prelude to negative repercussions on fish health, which may affect the aquaculture productivity. The present findings recommend precautions in relation to accidental or intentional overozonation in fish-farming, even when short-term events are considered. The strategies to mitigate the impact of ozonation in S. senegalensis may include a dietary extra supplementation of antioxidants (regularly, or punctually in cases of overozonation).publishe

Genome-wide signatures of complex introgression and adaptive evolution in the big cats.

The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages

Effect of the Ethyl Acetate Fraction of Eugenia uniflora on Proteins Global Expression during Morphogenesis in Candida albicans

Candida albicans is able to switch from yeast to hyphal growth and this is an essential step for tissue invasion and establishment of infection. Due to the limited drug arsenal used to treat fungal infections and the constant emergence of resistant strains, it is important to search for new therapeutic candidates. Therefore, this study aimed to investigate by proteomic analysis the role of a natural product (Eugenia uniflora) in impairing hypha formation in C. albicans. We also tested the potential action of E. uniflora to prevent and treat oral candidiasis induced in a murine model of oral infection and the ability of polymorphonuclear neutrophils to phagocytize C. albicans cells treated with the ethyl acetate fraction of the extract. We found that this fraction greatly reduced hypha formation after morphogenesis induction in the presence of serum. Besides, several proteins were differentially expressed in cells treated with the fraction. Surprisingly, the ethyl acetate fraction significantly reduced phagocytosis in C. albicans (Mean 120.36 ± 36.71 yeasts/100 PMNs vs. 44.68 ± 19.84 yeasts/100 PMNs). Oral candidiasis was attenuated when C. albicans cells were either pre-incubated in the presence of E. uniflora or when the fraction was applied to the surface of the oral cavity after infection. These results were consistent with the reduction in CFU counts (2.36 vs. 1.85 Log10 CFU/ml) and attenuation of tissue damage observed with histopathological analysis of animals belonging to treated group. We also observed shorter true hyphae by direct examination and histopathological analysis, when cells were treated with the referred natural product. The E. uniflora ethyl acetate fraction was non-toxic to human cells. E. uniflora may act on essential proteins mainly related to cellular structure, reducing the capacity of filamentation and attenuating infection in a murine model, without causing any toxic effect on human cells, suggesting that it may be a future therapeutic alternative for the treatment of Candida infections

Psicología Y educación a distancia : una revisión de la literatura

O presente estudo investigou as contribuições da Psicologia para a educação a distância – EAD. Para isso, realizou-se revisão bibliográfica de publicações nacionais, entre 1999 e 2009, nas bases de dados SciELO, Lilacs, PsycINFO, BVS e Google Acadêmico. Foram selecionados 69 estudos, dos quais se excluíram 15, por não serem compatíveis com a pesquisa. Os resultados evidenciaram nove eixos temáticos: (1) tecnologia educacional a distância com fundamentos psicológicos, (2) afeição, (3) papel do tutor/professor, (4) teorias psicológicas, (5) interatividade, (6) evasão, (7) relatos de experiências, (8) avaliação de treinamento, desenvolvimento e educação a distância e (9) outros. Os temas tecnologia educacional a distância com fundamentos psicológicos e afeição obtiveram maior frequência nas publicações. Neste estudo, registrou-se, também, que, embora em ascensão desde 2006, os anos de maiores publicações da Psicologia na educação a distância foram 2008 e 2009. Sugere-se que estudos futuros ampliem esta pesquisa para incluir bases de dados internacionais.This study investigated the contributions of Psychology to Distance Learning. A literature review of national publications between 1999 to 2009 was made in the electronic databases SciELO, LILACS, PsycINFO, BVS and Google Scholar. From the 69 studies selected, 15 were excluded because they were not compatible with the research. The results showed nine themes: (1) the distance learning technology with psychological grounding, (2) affection, (3)the role of the tutor/professor, (4) psychological theories, (5) interactivity, (6) dropout, (7) reports of experiences, (8) assessment of distance training, development and education and (9) others. The topics distance education technology with psychological grounding and affection had a larger frequency in the publications. Since 2006, there was an increasing number of publications in psychology distance education, but the years of major publications were from 2008 to 2009. It is suggested that future studies expand this research including international databases.El presente estudio investigó las contribuciones de la Psicología para la Educación a Distancia – EAD. Para eso, fue realizada una revisión bibliográfica de publicaciones nacionales, entre 1999 y 2009 en las bases de datos SciELO, Lilacs, PsycINFO, BVS y Google Académico. Fueron seleccionados 69 estudios, de los cuales se excluyeron 15, por no ser compatibles con la pesquisa. Los resultados evidenciaron nueve ejes temáticos (1) tecnología educacional la distancia con fundamentos psicológicos; (2) afección; (3) papel del tutor/profesor; (4) teorías psicológicas; (5) interactividad; (6) evasión; (7) relatos de experiencias, (8) evaluación de entrenamiento, desarrollo y educación distancia y (9) otros. Los temas tecnología educacional a distancia con fundamentos psicológicos y afección obtuvieron mayor frecuencia en las publicaciones. En ese estudio se registró, también, que, aunque en ascensión desde 2006, los años de mayores publicaciones de la psicología en la educación a distancia, fueron 2008 y 2009. Se sugiere que estudios futuros amplíen esa pesquisa para incluir bases de datos internacionales

Distribuição de potássio em gotejamento com fertirrigação em diferentes pontos de injeção na linha principal

[EN] The purpose of this research was to evaluate the K2O distribution uniformity by surface drip irrigation at Universitat Politecnica de Valencia, Valencia, Spain (39º 29′ N, 0º 23′ W, 20 m). The irrigation was performed by drip lines with not-compensated emitters, spaced 0.3 m. The fertigation was realized using a fertilizer injector pump of electric action with injection of 0.25 h. The experimental design used completely randomized blocks with five treatments and four replications. The treatments consisted of injection in five distances, located at 10; 20; 30; 40; 50 m of the first drip line. Samples were collected in emitters located at the start, at 1/3, at 2/3 and at the end of the drip lines. The nutrient concentration was determined by flame spectrophotometry. The Christiansen's uniformity coefficients (CUC), of distribution (DUC), of statistical (SUC) and of emission (eUC) were estimated. The K2O concentration and distribution decreased linearly with the increase of the injection distance. In all treatments, the CUC, SUC and DUC were described as 'excellent'. The eUC was described as 'recommended' only at smaller injection distances.[PT] Objetivando fornecer subsídios para os produtores aperfeiçoarem o manejo da fertirrigação em pequenas áreas, avaliou-se, na Universitat Politècnica de València, Valência, Espanha (39° 29′ N, 0° 23′ W, 20 m), a uniformidade de distribuição do K2O via irrigação por gotejamento superficial em função da distância do ponto de injeção na linha principal. A irrigação foi efetuada por linhas laterais com emissores não compensantes, espaçados de 0,3 m. Na fertirrigação, foi utilizada uma bomba injetora de fertilizante de acionamento elétrico, com o tempo de injeção de 0,25 h. O delineamento experimental foi o de blocos casualizados, com cinco tratamentos e quatro repetições. Os tratamentos consistiram em cinco pontos de injeção na linha principal, situados a: 10; 20; 30; 40 e 50 m da primeira linha lateral. Foram coletadas amostras em emissores localizados no início, a 1/3, a 2/3 e no final das linhas laterais. A concentração do nutriente foi determinada por espectrofotometria de chama. Foram estimados os coeficientes de uniformidade de Christiansen (CUC), de distribuição (CUD), estatístico (CUE) e de emissão (CUe). A concentração e a distribuição de K2O diminuíram linearmente com o aumento da distância do ponto de injeção. Em todos os tratamentos, o CUC, CUE e CUD foram classificados como ‘excelente’. O CUe foi classificado como ‘recomendado’ apenas na menor distância de injeção.To the Coordination of Improvement of Higher Education Personnel (CAPES) for grant the Doctoral Sandwich Abroad scholarship and the Universitat Politècnica de València (UPV), for providing the experimental area and all equipment and supplies needed for the research.Do Bomfim, GV.; Manzano Juarez, J.; De Azevedo, BM.; Vasconcelos, DV.; Viana, TVDA. (2014). Potassium distribution in drip irrigation with fertigation for different injection distances in the main line. Engenharia Agrícola. 34(6):1151-1161. doi:10.1590/S0100-69162014000600011S1151116134