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61.
Culture Media Statistical Optimization for Biomass Production of a Ligninolytic Fungus for Future Rice Straw Degradation 总被引:1,自引:0,他引:1
Viviana Sarria-Alfonso John Sánchez-Sierra Mauricio Aguirre-Morales Ivonne Gutiérrez-Rojas Nubia Moreno-Sarmiento Raúl A. Poutou-Piñales 《Indian journal of microbiology》2013,53(2):199-207
The main objective of this study was to optimize a culture media for low scale biomass production of Pleurotus spp. Future applications of this optimization will be implemented for “in situ” rice straw degradation, increase soil nutrients availability, and lower residue and rice culture management costs. Soil samples were taken from different points in six important rice production cities in Colombia. For carbon and nitrogen source selection a factorial 42 design was carried out. The Plackett-Burman design permitted to detect carbon, nitrogen and inducer effects on fungus growth (response variable for all designs). This optimization was carried out by a Box-Behnken design. Finally a re-optimization assay for glucose concentration was performed by means of a One Factor design. Only 4/33 (12 %) isolates showed and important laccase or manganese peroxidase activity compared to Pleurotus ostreatus (HPB/P3). We obtained an increased biomass production in Pleurotus spp. (T1.1.) with glucose, followed by rice husk. Rice straw was considered an inducing agent for lignin degradation. Glucose was a significant component with positive effects, whereas Tween 80 and pH had negative effects. On the contrary, rice husk, yeast extract and CaCl2 were not significant components for increase the biomass production. Final media composition consisted of glucose 25 g L?1, yeast extract 5 g L?1, Tween 80 0.38 % (v/v), Rice husk 10 g L?1, CaCl2 1 g L?1, and pH 4.88 ± 0.2. The Box-Behnken polynomial prediction resulted to be lower than the experimental validation of the model (6.59 vs. 6.91 Log10 CFU ml?1 respectively). 相似文献
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Mayada Achour Marc Mousli Mahmoud Alhosin Abdulkhaleg Ibrahim Jean Peluso Christian D. Muller Valérie B. Schini-Kerth Ali Hamiche Sirano Dhe-Paganon Christian Bronner 《Biochemical and biophysical research communications》2013,430(1):208-212
Ubiquitin-like containing PHD and Ring finger 1 (UHRF1) contributes to silencing of tumor suppressor genes by recruiting DNA methyltransferase 1 (DNMT1) to their hemi-methylated promoters. Conversely, demethylation of these promoters has been ascribed to the natural anti-cancer drug, epigallocatechin-3-gallate (EGCG). The aim of the present study was to investigate whether the UHRF1/DNMT1 pair is an important target of EGCG action. Here, we show that EGCG down-regulates UHRF1 and DNMT1 expression in Jurkat cells, with subsequent up-regulation of p73 and p16INK4A genes. The down-regulation of UHRF1 is dependent upon the generation of reactive oxygen species by EGCG. Up-regulation of p16INK4A is strongly correlated with decreased promoter binding by UHRF1. UHRF1 over-expression counteracted EGCG-induced G1-arrested cells, apoptosis, and up-regulation of p16INK4A and p73. Mutants of the Set and Ring Associated (SRA) domain of UHRF1 were unable to down-regulate p16INK4A and p73, either in the presence or absence of EGCG. Our results show that down-regulation of UHRF1 is upstream to many cellular events, including G1 cell arrest, up-regulation of tumor suppressor genes and apoptosis. 相似文献
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Joan Vergés Gifra 《Ethnic and racial studies》2013,36(2):204-221
AbstractWhat kind of arguments can be used to justify a coercive language policy favouring the language of a cultural minority over the majority language of a state? To answer this question we will focus mainly on the language policy of the Catalan government and, to a lesser extent, on the language policies of the Basque Country and Quebec. Our aim is to develop a typology of arguments and try to show that each argument resorts to a different reason for coercion and has both virtues and flaws. 相似文献
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Donatella Camerino Paul Maurice Conway Samantha Sartori Paolo Campanini Madeleine Estryn‐Béhar Beatrice Isabella Johanna Maria van der Heijden 《Chronobiology international》2013,30(2-3):425-442
Satisfactory work ability is sustained and promoted by good physical and mental health and by favorable working conditions. This study examined whether favorable and rewarding work‐related factors increased the work ability among European nurses. The study sample was drawn from the Nurses' Early Exit Study and consisted of 7,516 nursing staff from seven European countries working in state‐owned and private hospitals. In all, 10.8% were day, 4.2% were permanent night, 20.9% were shift without night shift, and 64.1% were shift workers with night shifts. Participants were administered a composite questionnaire at baseline (Time 0) and 1 yr later (Time 1). The Work Ability Index (WAI) at Time 1 was used as the outcome measure, while work schedule, sleep, rewards (esteem and career), satisfaction with pay, work involvement and motivation, and satisfaction with working hours at Time 0 were included as potential determinants of work ability. Univariate and multivariate analyses were conducted after adjusting for a number of confounders (i.e., country, age, sex, type of employment, family status, and other job opportunities in the same area). Work schedule was not related to Time 1 changes in WAI. Higher sleep quality and quantity and more favorable psychosocial factors significantly increased work ability levels. Higher sleep quality and quantity did not mediate the effect of work schedule on work ability. No relevant interaction effects on work ability were observed between work schedule and the other factors considered at Time 0. As a whole, sleep and satisfaction with working time were gradually reduced from day work to permanent night work. However, scores on work involvement, motivation, and satisfaction with pay and rewards were the highest in permanent night workers and the lowest in rotating shift workers that included night shifts. 相似文献
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Nafizal Hossain Svetlana Ivanova Åsa Sjöholm Timén Jonas Bergare Tesfaledet Mussie Lena Bergström 《Bioorganic & medicinal chemistry letters》2013,23(14):4026-4030
A series of zwitterionic spirocyclic compounds were synthesised. In vitro data revealed that these compounds were potent CCR1 antagonists. In particular, 2, 4, 11 and 20 inhibited CCR1 mediated chemotaxis of THP-1 cells in a functional assay. 相似文献