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221.
Suppression subtractive hybridization was used to identify differentially expressed genes in hemocytes from carpet-shell clam Ruditapes decussatus stimulated with a mixture of dead bacterial strains. Putative function could be assigned to 100 of the 253 sequenced cDNAs. Based on sequence homologies, 3.16% of the total identified genes were possibly related to immune functions. Clam myticin isoforms 1, 2 and 3, and clam mytilin, with similarity with myticins and mytilins previously reported on Mytilus galloprovincialis were identified and characterized for the first time in clams. The analysis of their expression levels by quantitative PCR showed that they were induced by bacterial challenge. The results obtained in this work could be the first step leading to the understanding of molecular mechanisms by which these economically important marine bivalves respond to pathogens. 相似文献
222.
Extreme sensitivity to Yondelis (Trabectedin, ET-743) in low passaged sarcoma cell lines correlates with mutated p53 总被引:1,自引:0,他引:1
Moneo V Serelde BG Fominaya J Leal JF Blanco-Aparicio C Romero L Sánchez-Beato M Cigudosa JC Tercero JC Piris MA Jimeno J Carnero A 《Journal of cellular biochemistry》2007,100(2):339-348
Yondelis (Trabectedin, ET-743) is a marine anticancer agent currently in Phase II/III development in patients with advanced pretreated soft tissue sarcoma. In the present study, we generated a panel of low passaged tumor cell lines from samples explanted from chemonaive sarcoma patients with different tumor types. We assessed in vitro sensitivity/resistance to Trabectedin and doxorubicin in a panel of sarcoma cell lines and examined the correlation between molecular alterations in DNA repair genes and sensitivity to Trabectedin. We treated cell lines with Trabectedin and doxorubicin in both 96-h and clonogenic assays. In both assays, well-defined groups of resistant and sensitive cell lines were observed. Resistance to Trabectedin did not correlate with resistance to doxorubicin, indicating that the two drugs may have different mechanisms of resistance. p53 mutations and deletions correlated with extreme sensitivity (IC50 < 1 nM) to Trabectedin (P < 0.01). In a pair of isogenic cell lines differing only in the presence or absence of wild-type p53, the absence of p53 rendered cells threefold more sensitive to Trabectedin. 相似文献
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224.
Sprouty2 binds Grb2 at two different proline-rich regions, and the mechanism of ERK inhibition is independent of this interaction 总被引:2,自引:0,他引:2
Martínez N García-Domínguez CA Domingo B Oliva JL Zarich N Sánchez A Gutiérrez-Eisman S Llopis J Rojas JM 《Cellular signalling》2007,19(11):2277-2285
Sprouty2 has been widely implicated in the negative regulation of the fibroblast growth factor receptor-extracellular regulated kinase (ERK) pathway. Sprouty2 directly interacts with the adapter protein Grb2, member of the receptor tyrosine kinase-induced signaling pathways. In considering the functional role of Grb2, we investigated whether the interaction with this protein was responsible for ERK pathway inhibition. We found that the binding between Sprouty2 and Grb2 is constitutive, independent of Sprouty2 tyrosine phosphorylation, although it is increased when fibroblast growth factor receptor is activated. This connection is mediated by the N-terminal SH3 domain of Grb2 and two Sprouty2 proline-rich stretches (residues 59-64 and 303-307). Most importantly, a double Sprouty2 mutant (hSpry2 P59AP304A), which is unable to bind Grb2, developed at a similar inhibition level of fibroblast growth factor receptor-ERK pathway than that which originated from Sprouty2 wt. These results are evidence that the Sprouty2 mechanism of ERK inhibition is independent of Grb2 binding. 相似文献
225.
Andreas Kicherer Stefan Schaltegger Heinrich Tschochohei Beatriz Ferreira Pozo 《The International Journal of Life Cycle Assessment》2007,12(7):537-543
Goal, Scope and Background The eco-efficiency analysis and portfolio is a powerful decision support tool for various strategic and marketing issues.
Since its original academic development, the approach has been refined during the last decade and applied to a multitude of
projects. BASF, as possibly the most prominent company using and developing this tool, has applied the eco-efficiency approach
to more than 300 projects in the last 7 years. One of the greatest difficulties is to cover both dimensions of eco-efficiency
(costs or value added and environmental impact) in a comparable manner. This is particularly a challenge for the eco-efficiency
analyses of products.
Methods In this publication, an important approach and field of application dealing with product decisions based on the combination
of Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) is described in detail. Special emphasis is put on the quantitative
assessment of the relation of costs and environmental impacts. In conventional LCA an assessment of environmental impact categories
is often made by normalization with inhabitant equivalents. This is necessary to be able to compare the different environmental
impact categories, because of each different unit. For the proposed eco-efficiency analysis, the costs of products or processes
are also normalized with adapted gross domestic product figures.
Results and Discussion The ratio between normalized environmental impact categories and normalized costs (RE,C) is used for the graphical presentation of the results in an eco-efficiency portfolio. For the interpretation of the results
of an eco-efficiency analysis, it is important to distinguish ratios RE,C which are higher than one from ratios lower than one. In the first case, the environmental impact is higher than the cost
impact, while the inverse is true in the second case. This is very important for defining which kind of improvement is needed
and defining strategic management decisions. The paper shows a statistical evaluation of the RE,C factor based on the results of different eco-efficiency analyses made by BASF. For industries based on large material flows
(e.g. chemicals, steel, metals, agriculture), the RE,C factor is typically higher than one.
Conclusions and Recommendations This contribution shows that LCC and LCA may be combined in a way that they mirror the concept of eco-efficiency. LCAs that
do not consider LCC may be of very limited use for company management. For that very reason, corporations should install a
data management system that ensures equal information on both sides of the eco-efficiency coin. 相似文献
226.
Andrade PM Ribeiro BG Bozza MT Costa Rosa LF Tavares do Carmo MG 《Prostaglandins, leukotrienes, and essential fatty acids》2007,77(3-4):139-145
The effect of fish-oil supplementation (FO-S) on the immune responses of elite swimmers was investigated. In a randomized placebo-controlled trial, swimmers received either fish-oil capsules (n=10) containing long chain polyunsaturated fatty acids (FA) of n-3 (LCPUFA n-3) or placebo capsules (n=10), both for 6 weeks. Plasma FA, immunological markers, insulin and cortisol were evaluated. The FO-S resulted in an increase in LCPUFA n-3 and a decrease in arachidonic n-6 FA in plasma and a reduction in the production of interferon-gamma by cultured cells. A reduction in the production of tumor necrosis factor-alpha was observed in both groups. An increase in interleukin-2 production and no significant difference in interleukin-4 were also observed. FO-S was able to attenuate the exercise-induced increases in prostaglandin E2. Circulating concentrations of insulin did not change, while cortisol and glucose showed increase after the study period. These results suggest that FO-S influence exercise-associated immune responses in competitive swimmers. 相似文献
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228.
Gunnarsen Klara Cecilia Schjoerring Jan Kofod Gómez-Muñoz Beatriz de Neergaard Andreas Jensen Lars Stoumann 《Plant and Soil》2022,477(1-2):241-258
Plant and Soil - Plant-available silicon (Si) is limited in strongly weathered tropical soils. The aim of the study was to evaluate Si fertilisation as a strategy to improve phosphorus (P)... 相似文献
229.