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981.
Sabrina Spatari Michael Betz Harald Florin Martin Baitz Michael Faltenbacher 《The International Journal of Life Cycle Assessment》2001,6(2):81-84
The growing availability of software tools has increased the speed of generating LCA studies. Databases and visual tools for
constructing material balance modules greatly facilitate the process of analyzing the environmental aspects of product systems
over their life cycle. A robust software tool, containing a large LCI dataset and functions for performing LCIA and sensitivity
analysis will allow companies and LCA practitioners to conduct systems analyses efficiently and reliably. This paper discusses
how the GaBi 3 software tool can be used to perform LCA and Life Cycle Engineering (LCE), a methodology that combines life
cycle economic, environmental, and technology assessment. The paper highlights important attributes of LCA software tools,
including high quality, well-documented data, transparency in modeling, and data analysis functionality. An example of a regional
power grid mix model is used to illustrate the versatility of GaBi 3. 相似文献
982.
983.
Fuchshofer R Ullmann S Zeilbeck LF Baumann M Junglas B Tamm ER 《Histochemistry and cell biology》2011,136(3):301-319
Structural changes of podocytes and retraction of their foot processes are a critical factor in the pathogenesis of minimal
change nephritis and glomerulosclerosis. Here we tested, if connective tissue growth factor (CTGF) is involved in podocyte
injury during acute and chronic puromycin aminonucleoside nephrosis (PAN) as animal models of minimal change nephritis, and
focal segmental glomerulosclerosis, respectively. Rats were treated once (acute PAN) or for 13 weeks (chronic PAN). In both
experimental conditions, CTGF and its mRNA were found to be highly upregulated in podocytes. The upregulation correlated with
onset and duration of proteinuria in acute PAN, and glomerulosclerosis and high expression of glomerular fibronectin, and
collagens I, III, and IV in chronic PAN. In vitro, treatment of podocytes with recombinant CTGF increased amount and density
of actin stress fibers, the expression of actin-associated molecules such as podocalyxin, synaptopodin, ezrin, and actinin-4,
and activation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK). Moreover, we observed increased
podocyte expression of mRNA for transforming growth factor (TGF)-β2, TGF-β receptor II, fibronectin, and collagens I, III,
and IV. Treatment of cultured podocytes with puromycin aminonucleoside resulted in loss of actin stress fibers and cell death,
effects that were partially prevented when CTGF was added to the culture medium. Depletion of CTGF mRNA in cultured podocytes
by RNA interference reduced both the number of actin stress fibers and the expression of actin-associated molecules. We propose
that the expression of CTGF is acutely upregulated in podocytes as part of a cellular attempt to repair structural changes
of the actin cytoskeleton. When the damaging effects on podocyte structure and function persist chronically, continuous CTGF
expression in podocytes is a critical factor that promotes progressive accumulation of glomerular extracellular matrix and
glomerulosclerosis. 相似文献
984.
985.
Histone deacetylase inhibitor activity in royal jelly might facilitate caste switching in bees 总被引:2,自引:0,他引:2
Spannhoff A Kim YK Raynal NJ Gharibyan V Su MB Zhou YY Li J Castellano S Sbardella G Issa JP Bedford MT 《EMBO reports》2011,12(3):238-243
Worker and queen bees are genetically indistinguishable. However, queen bees are fertile, larger and have a longer lifespan than their female worker counterparts. Differential feeding of larvae with royal jelly controls this caste switching. There is emerging evidence that the queen-bee phenotype is driven by epigenetic mechanisms. In this study, we show that royal jelly--the secretion produced by the hypopharyngeal and mandibular glands of worker bees--has histone deacetylase inhibitor (HDACi) activity. A fatty acid, (E)-10-hydroxy-2-decenoic acid (10HDA), which accounts for up to 5% of royal jelly, harbours this HDACi activity. Furthermore, 10HDA can reactivate the expression of epigenetically silenced genes in mammalian cells. Thus, the epigenetic regulation of queen-bee development is probably driven, in part, by HDACi activity in royal jelly. 相似文献
986.
Liu X Wu J Yammine M Zhou J Posocco P Viel S Liu C Ziarelli F Fermeglia M Pricl S Victorero G Nguyen C Erbacher P Behr JP Peng L 《Bioconjugate chemistry》2011,22(12):2461-2473
With the aim of developing dendrimer nanovectors with a precisely controlled architecture and flexible structure for DNA transfection, we designed PAMAM dendrimers bearing a triethanolamine (TEA) core, with branching units pointing away from the center to create void spaces, reduce steric congestion, and increase water accessibility for the benefit of DNA delivery. These dendrimers are shown to form stable nanoparticles with DNA, promote cell uptake mainly via macropinocytosis, and act as effective nanovectors for DNA transfection in vitro on epithelial and fibroblast cells and, most importantly, in vivo in the mouse thymus, an exceedingly challenging organ for immune gene therapy. Collectively, these results validate our rational design approach of structurally flexible dendrimers with a chemically defined structure as effective nanovectors for gene delivery, and demonstrate the potential of these dendrimers in intrathymus gene delivery for future applications in immune gene therapy. 相似文献
987.
Sabrina Laugesen Alexis Bergoin Michel Rossignol 《Plant Physiology and Biochemistry》2004,42(12):929-936
Protein phosphorylation constitutes a major type of post-translational modification that mobilizes a high number of genes, especially in plants, is involved in many crucial cell functions and largely participates to the complexity of the proteomes. For several biological and technical reasons, the characterization of phosphorylation sites requires complex procedures. In this review, the different approaches presently available to select phosphoproteins and phosphopeptides are described. A special emphasis is then given to the numerous strategies that have emerged for the analysis of phosphorylation sites by various techniques of mass spectrometry. Finally, the few attempts proposed for the quantification of phosphorylation events are presented. In another part, the results of the efforts made in the plant area to analyze the phosphoproteome are compared to those in other biological systems. These overviews are put together to delineate, according to the objectives pursued, the different strategies possible and the corresponding challenges. 相似文献
988.
Sabrina do Couto de Miranda Mercedes Bustamante Michael Palace Stephen Hagen Michael Keller Laerte Guimarães Ferreira 《Biotropica》2014,46(2):125-138
The Cerrado, the savanna biome in central Brazil, mostly comprised of woodland savanna, is experiencing intense and fast land use changes. To understand the changes in Cerrado carbon stocks, we present an overview of biomass distribution in different Cerrado vegetation types (i.e., grasslands, shrublands and forestlands). We surveyed 26 studies including 170 Cerrado sites. The grasslands presented mean total biomass of 24 Mg/ha, with 70 percent allocated in the belowground portion. In shrublands, the mean total biomass was 58 Mg/ha being 58 percent in the belowground portion. Finally, in forestlands the mean total biomass was 98 Mg/ha with 18 percent as belowground biomass. The surveyed studies presented 12 allometric equations for biomass estimate, most involving both diameter and height. Data on wood density for Cerrado shrubs and trees are not abundant and the average value was 0.66 g/cm3, similar to that found in the central portion of the Amazon Forest. We also examined the relationship between total precipitation and dry‐season intensity with biomass variation in the Cerrado shrubland using data from tropical rainfall measurement mission (TRMM) for the period 2000–2010. Dry‐season precipitation amount in cerrado areas in severe drought regions explained 29 percent of the variation in aboveground woody biomass. This finding is important in the face of the predictions of longer and more severe dry seasons in the region due to climate change. 相似文献
989.
Peroxisome proliferation-associated control of reactive oxygen species sets melanocortin tone and feeding in diet-induced obesity 总被引:1,自引:0,他引:1
990.
Developmental constraints revealed by co-variation within and among molar rows in two murine rodents
Sabrina Renaud Sophie Pantalacci Jean-Pierre Quéré Vincent Laudet Jean-Christophe Auffray 《Evolution & development》2009,11(5):590-602
SUMMARY Morphological integration corresponds to interdependency between characters that can arise from several causes. Proximal causes of integration include that different phenotypic features may share common genetic sets and/or interact during their development. Ultimate causes may be the prolonged effect of selection favoring integration of functionally interacting characters, achieved by the molding of these proximal causes. Strong and direct interactions among successive teeth of a molar row are predicted by genetic and developmental evidences. Functional constraints related to occlusion, however, should have selected more strongly for a morphological integration of occluding teeth and a corresponding evolution of the underlying developmental and genetic pathways. To investigate how these predictions match the patterns of phenotypic integration, we studied the co‐variation among the six molars of the murine molar row, focusing on two populations of house mice (Mus musculus domesticus) and wood mice (Apodemus sylvaticus). The size and shape of the three upper and lower molars were quantified and compared. Our results evidenced similar patterns in both species, size being more integrated than shape among all the teeth, and both size and shape co‐varying strongly between adjacent teeth, but also between occluding teeth. Strong co‐variation within each molar row is in agreement with developmental models showing a cascade influence of the first molar on the subsequent molars. In contrast, the strong co‐variation between molars of the occluding tooth rows confirms that functional constraints molded patterns of integration and probably the underlying developmental pathways despite the low level of direct developmental interactions occurring among molar rows. These patterns of co‐variation are furthermore conserved between the house mouse and the wood mouse that diverged >10 Ma, suggesting that they may constitute long‐running constraints to the diversification of the murine rodent dentition. 相似文献