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91.
Given the history of GMO conflict and debate, the GM animal future is dependent on the response of the regulatory landscape and its associated range of interest groups at national, regional and international levels. Focusing on the EU and the USA, this article examines the likely form of that multi-level response, the increased role of cultural values, the contribution of new and existing interest groups and the consequent implications for the commercialization of both green and red GM animal biotechnology. 相似文献
92.
Recent data suggests that PAS kinase acts as a signal integrator to adjust metabolic behavior in response to nutrient conditions. Specifically, PAS kinase controls the partitioning of nutrient resources between the myriad of possible fates. In this capacity, PAS kinase elicits a pro-growth program, which includes both signaling and metabolic control, both in yeast and in mammals. We propose that, like other kinases possessing these properties-AMPK and TOR, PAS kinase might be target for therapy of diabetes, obesity and cancer. 相似文献
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Victoria Nelissen Tobias Rütting Dries Huygens Greet Ruysschaert Pascal Boeckx 《Global Change Biology Bioenergy》2015,7(4):635-645
Biochar addition to soils has been proposed as a means to increase soil fertility and carbon sequestration. However, its effect on soil nitrogen (N) cycling and N availability is poorly understood. To gain better insight into the temporal variability of the impact of biochar on gross soil N dynamics, two 15N tracing experiments, in combination with numerical data analysis, were conducted with soil from a biochar field trial, 1 day and 1 year after application of a woody biochar type. The results showed accelerated soil N cycling immediately following biochar addition, with increased gross N mineralization (+34%), nitrification (+13%) and ammonium (NH4+) and nitrate (NO3−) immobilization rates (+4500% and +511%, respectively). One year after biochar application, the biochar acted as an inert substance with respect to N cycling. In the short term, biochar's labile C fraction and a pH increase can explain stimulated microbial activity, while in the longer term, when the labile C fraction has been mineralized and the pH effect has faded, the accelerating effect of biochar on N cycling ceases. In conclusion, biochar accelerates soil N transformations in the short-term through stimulating soil microbial activity, thereby increasing N bio-availability. This effect is, however, temporary. 相似文献
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Annelies Vandersteen Marcelo F. Masman Greet De Baets Wim Jonckheere Kees van der Werf Siewert J. Marrink Jef Rozenski Iryna Benilova Bart De Strooper Vinod Subramaniam Joost Schymkowitz Frederic Rousseau Kerensa Broersen 《The Journal of biological chemistry》2012,287(44):36732-36743
Current therapeutic approaches under development for Alzheimer disease, including γ-secretase modulating therapy, aim at increasing the production of Aβ1–38 and Aβ1–40 at the cost of longer Aβ peptides. Here, we consider the aggregation of Aβ1–38 and Aβ1–43 in addition to Aβ1–40 and Aβ1–42, in particular their behavior in mixtures representing the complex in vivo Aβ pool. We demonstrate that Aβ1–38 and Aβ1–43 aggregate similar to Aβ1–40 and Aβ1–42, respectively, but display a variation in the kinetics of assembly and toxicity due to differences in short timescale conformational plasticity. In biologically relevant mixtures of Aβ, Aβ1–38 and Aβ1–43 significantly affect the behaviors of Aβ1–40 and Aβ1–42. The short timescale conformational flexibility of Aβ1–38 is suggested to be responsible for enhancing toxicity of Aβ1–40 while exerting a cyto-protective effect on Aβ1–42. Our results indicate that the complex in vivo Aβ peptide array and variations thereof is critical in Alzheimer disease, which can influence the selection of current and new therapeutic strategies. 相似文献
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Direct Spectrophotometric Measurement of Photosystem I and Photosystem II Activities of Photosynthetic Membrane Preparations from Cyanophora paradoxa, Phormidium laminosum, and Spinach 下载免费PDF全文
Vesicles prepared with the French press from membranes of cyanelles of Cyanophora paradoxa retain O2 evolution activity with rates up to 500 micromoles 2,6-dichlorophenolindophenol reduced per hour per milligram chlorophyll. This activity is immediately lost when the vesicles are transferred from the sucrose-phosphate-citrate preparation buffer into dilute phosphate buffer. Similar preparations from Phormidium laminosum, a thermophilic cyanobacterium retain activity under such conditions. Photosystem I activities of both cyanobacterial vesicle preparations were determined by direct spectrophotometric measurement of N,N,N′,N′-tetramethyl-p-phenylenediamine photooxidation in the presence of anthraquinone-2-sulfonate. The rates so determined were compared with rates of O2 taken up in the presence of methyl viologen or anthraquinone-2-sulfonate as electron acceptors. The predicted stoichiometry of two was observed for moles of N,N,N′,N′-tetramethyl-p-phenylenediamine oxidized per mole of oxygen taken up. Anthraquinone-2-sulfonate was the better electron acceptor, and maximal rates of 943 micromoles per hour per milligram chlorophyll for O2 uptake were observed for Phormidium laminosum preparations in the presence of superoxide dismutase. For purposes of comparison, spinach chloroplasts were assayed for similar activities. All preparations were readily assayed for photosystem I activity by the direct spectrophotometric method, which has advantages of simplicity and freedom from errors introduced by photoxidation of other substrates by photosystem I when O2 uptake is measured. 相似文献
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