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1.
2.
Summary The use of reticulated polyurethane foam as a support material for the immobilization of methanogenic associations and its application to the anaerobic treatment of fine particulate solid wastes was investigated. The colonization of polyurethane support particles in a continuous upflow reactor fed on a mixture of acetate, propionate and butyrate, was both rapid and dense. The combination of rumen microorganisms and colonized support particles in a two-phase digester resulted in an efficient anaerobic decomposition of papermill sludge. 相似文献
3.
Carlos H. Prosperi 《Journal of phycology》1994,30(2):222-224
Nostoc cordubensis Prosperi (Cyanophyta, Nostocaceae) is characterized by its mucilaginous colonies. Much of this mucilage is produced by heterocysts. By controlling growth conditions, heterocysts with and without mucilage were obtained. Mucilaginous heterocysts retained nitrogen-fixing capability at high oxygen concentrations, whereas heterocysts lacking mucilage were unable to fix nitrogen at oxygen concentrations higher than 20%. Comparison of results obtained using tetrazolium salts as indicators of highly reduced zones showed similar results. 相似文献
4.
The influence of DNA topology on stainability with the externally binding fluorochromes Hoechst 33258 (HO) and mithramycin (MI) was investigated in HeLa nuclei in comparison with the intercalating dye propidium iodide (PI). Changes in DNA topology were induced with a mild DNAse I treatment. Stainability properties of untreated and nuclease-treated nuclei were compared with those of the supercoiled-circular and the relaxed-linear forms of the plasmid pBR322. DNAse-treated nuclei stained with HO showed a higher fluorescence intensity than control samples, independently of the dye concentration, in contrast with the findings obtained with PI. Similar behaviour was observed with the relaxed-linear form of pBR322, compared with the supercoiled-circular molecule. With MI, the stainability of HeLa nuclei did not depend on the DNA topology, whereas the stainability of the plasmid was similar to that of HO. In order to assess whether this discrepancy depended on differences in the availability of DNAse-sensitive sites to the fluorochromes, fluorescence resonance energy transfer (FRET) studies were performed in nuclei stained with HO+PI, or with HO+MI dye pairs. After DNAse I digestion, the relative FRET efficiency between donor (HO) and acceptor molecules (PI or MI) was reduced significantly only when MI was the acceptor. This result may be due to greater stainability of DNAse-sensitive sites with HO than with MI. These findings indicate that DNA stainability with base-specific fluorochromes may be affected by the topology of chromatin regions. 相似文献
5.
Guano F Bernardi R Negri C Donzelli M Prosperi E Ricotti GA Scovassi AI 《Cell death and differentiation》1994,1(2):101-107
Zinc ions exert an inhibitory effect on Ca(2+)Mg(2+)-dependent endonuclease which is supposed to be responsible for the fragmentation of DNA during apoptosis. In the experimental system we used, that is HeLa cells treated with VP-16, the protection from internucleosomal DNA degradation is modulated by Zn concentration and appears to be dependent on the time after treatment. This effect does not prevent cell death or occurrence of apoptotic parameters, suggesting that DNA ladder appearance is not a crucial event in apoptosis. The activation of poly(ADP-ribose)polymerase following the administration of VP-16, is not observed in cells in which DNA fragmentation has been abolished by zinc, supporting the hypothesis that this event is regulated by the appearance of small-sized DNA fragments. 相似文献
6.
Moreau D Burstin J Aubert G Huguet T Ben C Prosperi JM Salon C Munier-Jolain N 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(4):755-768
Medicago truncatula is used as a model plant for exploring the genetic and molecular determinants of nitrogen (N) nutrition in legumes. In this
study, our aim was to detect quantitative trait loci (QTL) controlling plant N nutrition using a simple framework of carbon/N
plant functioning stemming from crop physiology. This framework was based on efficiency variables which delineated the plant’s
efficiency to take up and process carbon and N resources. A recombinant inbred line population (LR4) was grown in a glasshouse
experiment under two contrasting nitrate concentrations. At low nitrate, symbiotic N2 fixation was the main N source for plant growth and a QTL with a large effect located on linkage group (LG) 8 affected all
the traits. Significantly, efficiency variables were necessary both to precisely localize a second QTL on LG5 and to detect
a third QTL involved in epistatic interactions on LG2. At high nitrate, nitrate assimilation was the main N source and a larger
number of QTL with weaker effects were identified compared to low nitrate. Only two QTL were common to both nitrate treatments:
a QTL of belowground biomass located at the bottom of LG3 and another one on LG6 related to three different variables (leaf
area, specific N uptake and aboveground:belowground biomass ratio). Possible functions of several candidate genes underlying
QTL of efficiency variables could be proposed. Altogether, our results provided new insights into the genetic control of N
nutrition in M. truncatula. For instance, a novel result for M. truncatula was identification of two epistatic interactions in controlling plant N2 fixation. As such this study showed the value of a simple conceptual framework based on efficiency variables for studying
genetic determinants of complex traits and particularly epistatic interactions. 相似文献
7.
Jurgen Vercauteren Gertjan Beheydt Mattia Prosperi Pieter Libin Stijn Imbrechts Ricardo Camacho Bonaventura Clotet Andrea De Luca Zehava Grossman Rolf Kaiser Anders S?nnerborg Carlo Torti Eric Van Wijngaerden Jean-Claude Schmit Maurizio Zazzi Anna-Maria Geretti Anne-Mieke Vandamme Kristel Van Laethem 《PloS one》2013,8(4)
Introduction
Clinically evaluating genotypic interpretation systems is essential to provide optimal guidance in designing potent individualized HIV-regimens. This study aimed at investigating the ability of the latest Rega algorithm to predict virological response on a short and longer period.Materials & Methods
9231 treatment changes episodes were extracted from an integrated patient database. The virological response after 8, 24 and 48 weeks was dichotomized to success and failure. Success was defined as a viral load below 50 copies/ml or alternatively, a 2 log decrease from the baseline viral load at 8 weeks. The predictive ability of Rega version 8 was analysed in comparison with that of previous evaluated version Rega 5 and two other algorithms (ANRS v2011.05 and Stanford HIVdb v6.0.11). A logistic model based on the genotypic susceptibility score was used to predict virological response, and additionally, confounding factors were added to the model. Performance of the models was compared using the area under the ROC curve (AUC) and a Wilcoxon signed-rank test.Results
Per unit increase of the GSS reported by Rega 8, the odds on having a successful therapy response on week 8 increased significantly by 81% (OR = 1.81, CI = [1.76–1.86]), on week 24 by 73% (OR = 1.73, CI = [1.69–1.78]) and on week 48 by 85% (OR = 1.85, CI = [1.80–1.91]). No significant differences in AUC were found between the performance of Rega 8 and Rega 5, ANRS v2011.05 and Stanford HIVdb v6.0.11, however Rega 8 had the highest sensitivity: 76.9%, 76.5% and 77.2% on 8, 24 and 48 weeks respectively. Inclusion of additional factors increased the performance significantly.Conclusion
Rega 8 is a significant predictor for virological response with a better sensitivity than previously, and with rules for recently approved drugs. Additional variables should be taken into account to ensure an effective regimen. 相似文献8.
Differential involvement of DNases in HeLa cell apoptosis induced by etoposide and long term-culture
Torriglia A Negri C Chaudun E Prosperi E Courtois Y Counis MF Scovassi AI 《Cell death and differentiation》1999,6(3):234-244
We have applied to human HeLa cells two different stimuli of apoptosis: the antitumoral drug etoposide, and a more 'physiological' death condition, obtained by growing cells in the same medium for long time periods, for up to 10 days. Analysis of different parameters demonstrated that in both experimental systems the same apoptotic features are visible. However, the DNA degradation pattern appeared to be different, suggesting the involvement of different DNases. In this view, we have analyzed the activity and expression of Ca2+-Mg2+-dependent and acid DNases. We have observed that DNase I is not modulated during apoptosis. In contrast, the acid L-DNase II (derived from Leukocyte Elastase Inhibitor by post-translational modification), recently identified in our laboratory, is mainly active in the apoptotic pathway induced by long term-culture. Furthermore, we have provided evidence that while caspase 3 is activated by both inducers, caspase 1 is essential only for the etoposide-induced apoptosis. 相似文献
9.
Paola Perucca Sabrina Sommatis Roberto Mocchi Ennio Prosperi Lucia Anna Stivala Ornella Cazzalini 《Cell cycle (Georgetown, Tex.)》2015,14(24):3920-3928
DNA damage binding protein 2 (DDB2) is a protein involved in the early step of DNA damage recognition of the nucleotide excision repair (NER) process. Recently, it has been suggested that DDB2 may play a role in DNA replication, based on its ability to promote cell proliferation. We have previously shown that DDB2 binds PCNA during NER, but also in the absence of DNA damage; however, whether and how this interaction influences cell proliferation is not known. In this study, we have addressed this question by using HEK293 cell clones stably expressing DDB2Wt protein, or a mutant form (DDB2Mut) unable to interact with PCNA. We report that overexpression of the DDB2Mut protein provides a proliferative advantage over the wild type form, by influencing cell cycle progression. In particular, an increase in the number of S-phase cells, together with a reduction in p21CDKN1A protein level, and a shorter cell cycle length, has been observed in the DDB2Mut cells. These results suggest that DDB2 influences cell cycle progression thanks to its interaction with PCNA. 相似文献
10.
Julier B Huguet T Chardon F Ayadi R Pierre JB Prosperi JM Barre P Huyghe C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(8):1391-1406
In many legume crops, especially in forage legumes, aerial morphogenesis defined as growth and development of plant organs,
is an essential trait as it determines plant and seed biomass as well as forage quality (protein concentration, dry matter
digestibility). Medicago truncatula is a model species for legume crops. A set of 29 accessions of M. truncatula was evaluated for aerial morphogenetic traits. A recombinant inbred lines (RILs) mapping population was used for analysing
quantitative variation in aerial morphogenetic traits and QTL detection. Genes described to be involved in aerial morphogenetic
traits in other species were mapped to analyse co-location between QTLs and genes. A large variation was found for flowering
date, morphology and dynamics of branch elongation among the 29 accessions and within the RILs population. Flowering date
was negatively correlated to main stem and branch length. QTLs were detected for all traits, and each QTL explained from 5.2
to 59.2% of the phenotypic variation. A QTL explaining a large part of genetic variation for flowering date and branch growth
was found on chromosome 7. The other chromosomes were also involved in the variation detected in several traits. Mapping of
candidate genes indicates a co-location between a homologue of Constans gene or a flowering locus T (FT) gene and the QTL
of flowering date on chromosome 7. Other candidate genes for several QTLs are described.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献