Efeito da diluição na caracterização da biomassa de sistemas de tratamentos de efluentes por análise de imagem

O estudo da biomassa de sistemas de tratamento de efluentes por análise de imagem permite avaliar o seu estado de agregação assim como acompanhar as modificações por ela sofrida quando submetida a choques orgânicos ou hidráulicos. Certos processos de tratamento trabalham com uma forte concentração em biomassa, o que obriga a uma diluição prévia. O presente estudo avalia o efeito desta diluição sobre a caracterização da biomassa aeróbia e anaeróbia (agregada sob a forma de flocos ou grânulos ou isolada). Os resultados obtidos indicam que este efeito varia segundo a origem e tipo da biomassa e o tipo de água utilizada na diluição. Foi observado que a diluição provoca inicialmente um aumento do tamanho dos flocos para em seguida provocar a sua ruptura. Devido a fortes variações sofridas sobretudo em relação à quantificação das bactérias filamentosas, recomenda-se a opção por uma diluição e sua manutenção até o fim do experimento.The study by image analysis of biomass in wastewater treatment systems allow us to evaluate its aggregation state and to relate its changes to changes in the process operation conditions. In some processes, a high biomass concentration is used and dilution is necessary for visualisation by optical microscopy. The effect of the dilution factor on the measured characteristics of aerobic and anaerobic bacteria (aggregated as flocs or granules, or isolated) has been investigated. The results indicate that the effect depends on the origin and type of biomass and on the kind of water used for dilution. Dilution induces initially an increase of the floc size. The flocs are disrupted when the dilution factor is high. Due to the observed variations on the quantification of filamentous bacteria, it is recommended to select initially an appropriate dilution factor and to maintain it for the whole experiment.Brasil. Ministério da Ciência e Tecnologia. Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).Fundação para a Ciência e a Tecnologia (FCT).Embaixada de França em Portugal.Ministério da Ciência e Tecnologia. Instituto de Cooperação Científica e Tecnológica Internacional (ICCTI)

Zinc deficiency disrupts pain signaling promoting nociceptive but not inflammatory pain in mice

Abstract Zinc (Zn) is an essential micronutrient involved in the physiology of nervous system and pain modulation. There is little evidence for the role of nutritional Zn alternations to the onset and progression of neuropathic (NP) and inflammatory pain. The study investigated the effects of a zinc restricted diet on the development of pain. Weaned mice were submitted to a regular (38 mg/kg of Zn) or Zn deficient (11 mg/kg of Zn) diets for four weeks, pain responses evaluated (mechanical, cold and heat allodynia; formalin- and carrageenan-induced inflammatory hypernociception), plasma and tissues collected for biochemical and metabolomic analysis. Zn deficient diet inhibited animal growth (37%) and changed mice sensitivity pattern, inducing an intense allodynia evoked by mechanical, cold and heat stimulus for four weeks. The inflammatory pain behavior of formalin test was drastically reduced or absent when challenged by an inflammatory stimulus. Zn restriction also reduce plasma TNF, increase neuronal activation, oxidative stress, indicating a disruption of the immune response. Liver metabolomic analyses suggest a downregulation of lipid metabolism of arachidonic acid. Zn restriction since weaned disrupts pain signaling considerably and reduce inflammatory pain. Zn could be considered a predisposing factor for the onset of chronic pain such as painful neuropathies

In Silico, In Vitro and In Vivo Toxicological Assessment of BPP-BrachyNH2, A Vasoactive Proline-Rich Oligopeptide from Brachycephalus ephippium

BPP-BrachyNH2 is a proline-rich oligopeptide (PRO) firstly identified in skin secretion of the frog Brachycephalus ephippium, which possess in vitro inhibitory activity of angiotensin-I converting enzyme (ACE) and endothelium-dependent vasorelaxant activity. Considering its potential application in the treatment of cardiovascular diseases, the present work assessed the toxicological profile of the BPP-BrachyNH2. The in silico toxicity prediction was performed from the best model obtained through the optimization of the FASTA query peptide. This prediction study revealed that BPP-BrachyNH2 induced high predicted LD50 values for both humans and rats, and then is well-tolerated in the recommended range. The MTT assay was applied for the in vitro cytotoxic evaluation in murine macrophages. In this assay, a decrease of cell viability was not observed. The in vivo acute toxicological study was performed after the intraperitoneal administration of BPP-BrachyNH2 at doses of 5 and 50 mg/kg. After intraperitoneal administration, no death, alterations in behavioral parameters or weight gain curve was observed, as well as none in the serum biochemical parameters, and gross pathological and histopathological analyses. These observations demonstrates an acceptable safety profile for BPP-BrachyNH2, leading towards further studies focused on investigation of pharmacological and therapeutical applications for this peptide.info:eu-repo/semantics/publishedVersio

Biological evaluation of alginate-based hydrogels, with antimicrobial features by Ce(III) incorporation, as vehicles for a bone substitute

In this work three different hydrogels were developed to associate, as vehicles, with the synthetic bone substitute GR-HA. One based on an alginate matrix (Alg); a second on a mixture of alginate and chitosan (Alg/Ch); and a third on alginate and hyaluronate (Alg/HA), using Ca2+ ions as cross-linking agents. The hydrogels, as well as the respective injectable bone substitutes (IBSs), were fully characterized from the physical-chemical point of view. Weight change studies proved that all hydrogels were able to swell and degrade within 72 hours at pH 7.4 and 4.0, being Alg/HA the hydrogel with the highest degradation rate (80%). Rheology studies demonstrated that all hydrogels are non-Newtonian viscoelastic fluids, and injectability tests showed that IBSs presented low maximum extrusion forces, as well as quite stable average forces. In conclusion, the studied hydrogels present the necessary features to be successfully used as vehicles of GR-HA, particularly the hydrogel Alg/HA.The authors would like to acknowledge the financial support from FCT (Fundacao para a Ciencia e a Tecnologia) through the grant SFRH/BD/76237/2011 and project ENMED/0002/2010, from FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividade-under the project PEst-C/EME/UI0285/2011, as well as to the project I&DT BIOMAT&CELL n. 1372

Eficiência da seleção recorrente para redução da estatura de plantas em mamoneira (Ricinus communis L.) Recurrent selection efficiency for stature reduction of castor bean (Ricinus communis L.) plants

Realizou-se, o presente trabalho, com o objetivo de avaliar a eficiência da seleção recorrente para a redução da estatura de plantas de mamona da cultivar Guarani (Ricinus communis L.), tornando-a com porte adequado para facilitar a colheita manual e/ou mecânica. Foram realizados quatro ciclos de seleção recorrente com a utilização de progênies autofecundadas na cultivar Guarani para redução da estatura das plantas, nas condições edafoclimáticas dos municípios de São Manuel - SP, Botucatu - SP e Penápolis - SP. As avaliações de estatura das plantas e de produtividade de grãos (kg.ha-1), dos quatro ciclos de seleção e do ciclo original foram realizadas nos municípios de São Manuel - SP, Botucatu - SP e Penápolis - SP na safra 2005/2006, sob um delineamento de blocos casualizados com cinco repetições e parcela útil de 30 m². A análise de variância para as características avaliadas foi feita separadamente para cada local e conjuntamente para os três locais e, posteriormente, realizada a comparação das médias pelo teste de Tukey, a 5%. Foram estimados, para as três localidades, por análise de regressão, os ganhos genéticos dos quatros ciclos de seleção para estatura de plantas. A partir dos resultados obtidos pôde-se concluir que a seleção recorrente foi eficiente para a redução da estatura de plantas e que a cultivar de mamona Guarani apresenta variabilidade genética para essa característica e que a produtividade não foi influenciada pela redução da estatura de plantas.<br>The aim of this work was to evaluate the recurrent selection efficiency for reduction of stature of the castor bean plants of the Guarani cultivar (Ricinus communis L.), turning it with appropriate strucuture to facilitate the manual and/or mechanic harvest. Four cycles of recurrent selection were accomplished through the utilization of self-pollinated progenies in the Guarani cultivar for reduction of plants stature, in edaphclimatic conditions of São Manuel-SP, Botucatu-SP and Penápolis-SP towns. The evaluations of plants stature and yield (kg.ha-1) of the four selection cycles and the original cycle (cycle 0) were accomplished in São Manuel-SP, Botucatu-SP and Penápolis-SP, under a randomized block design with five repetitions and useful parcels of 30 m². The analysis of variance for the characteristics plant stature and yield was made apart to each environment and together for the three environment and, afterwards one performed the average comparison by the Tukey test using 5% of probability. One estimated for the three environments, by the regression analysis, the genetic gains of the four selection cycles for plant stature. One concluded that the recurrent selection was efficient to the reduction of plant stature and that Guarani castor bean cultivar could create genetic variability for this characteristic and the yield was not influenced by the reduction of plants stature

Anísio Teixeira e a educação integral

A concepção de educação integral, ancorada na extensão do tempo escolar, esteve sempre presente na obra de Anísio Teixeira. Partindo de uma justificativa, em 1930, ainda em parte baseada no espírito higienista-educacional, chega, em 1950, a uma proposta de educação escolar emancipadora de indivíduos e nação. Este texto apresenta a ideia de que a defesa da educação integral pelo autor passou por momentos diversos, mas conduziu o desenvolvimento de seu pensamento em relação a temas como alfabetização das massas, fim do dualismo escolar e qualidade da educação popular, mantendo-se como premissa ao longo de sua obra