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161.
Kolodziejek I Misas-Villamil JC Kaschani F Clerc J Gu C Krahn D Niessen S Verdoes M Willems LI Overkleeft HS Kaiser M van der Hoorn RA 《Plant physiology》2011,155(1):477-489
Syringolin A (SylA) is a nonribosomal cyclic peptide produced by the bacterial pathogen Pseudomonas syringae pv syringae that can inhibit the eukaryotic proteasome. The proteasome is a multisubunit proteolytic complex that resides in the nucleus and cytoplasm and contains three subunits with different catalytic activities: β1, β2, and β5. Here, we studied how SylA targets the plant proteasome in living cells using activity-based profiling and imaging. We further developed this technology by introducing new, more selective probes and establishing procedures of noninvasive imaging in living Arabidopsis (Arabidopsis thaliana) cells. These studies showed that SylA preferentially targets β2 and β5 of the plant proteasome in vitro and in vivo. Structure-activity analysis revealed that the dipeptide tail of SylA contributes to β2 specificity and identified a nonreactive SylA derivative that proved essential for imaging experiments. Interestingly, subcellular imaging with probes based on epoxomicin and SylA showed that SylA accumulates in the nucleus of the plant cell and suggests that SylA targets the nuclear proteasome. Furthermore, subcellular fractionation studies showed that SylA labels nuclear and cytoplasmic proteasomes. The selectivity of SylA for the catalytic subunits and subcellular compartments is discussed, and the subunit selectivity is explained by crystallographic data. 相似文献
162.
Controlled conditions were used to investigate the relationship between ion distribution in developing seeds of two Suaeda salsa populations and seed germination and seedling emergence. Seeds were harvested from S. salsa plants that had been treated with 1 or 400 mM NaCl for 122 (saline inland population) or 135 days (intertidal zone population) in a glasshouse. Germination and seedling emergence were evaluated under salinity. In both populations, more ions were accumulated in the pericarps of plants cultured in 400 mM NaCl than in 1 mM NaCl. Pericarps accumulated much higher ion concentrations in the intertidal zone population than in the saline inland population, while the opposite trend occurred for ion accumulation in the embryos. Seeds of plants from the intertidal zone population germinated more rapidly than those from plants of the saline inland population, regardless of the NaCl concentration during seed germination. However, seedling emergence under high salinity was lower with seeds from the intertidal zone population than with seeds from the saline inland population. In conclusion, S. salsa in the intertidal zone employs superior control of ion compartmentalization in the pericarps to tolerate salinity but requires a minimal level of ions in embryos to ensure seedling establishment in highly saline environments. This indicates that euhalophytes require salts during the mature seed stage to maintain seed viability and to ensure seedling emergence and population establishment. 相似文献
163.
Zhe Chen Jianting Cao Yang Cao Yue Zhang Fanji Gu Guoxian Zhu Zhen Hong Bin Wang Andrzej Cichocki 《Cognitive neurodynamics》2008,2(3):257-271
Electroencephalogram (EEG) is often used in the confirmatory test for brain death diagnosis in clinical practice. Because
EEG recording and monitoring is relatively safe for the patients in deep coma, it is believed to be valuable for either reducing
the risk of brain death diagnosis (while comparing other tests such as the apnea) or preventing mistaken diagnosis. The objective
of this paper is to study several statistical methods for quantitative EEG analysis in order to help bedside or ambulatory
monitoring or diagnosis. We apply signal processing and quantitative statistical analysis for the EEG recordings of 32 adult
patients. For EEG signal processing, independent component analysis (ICA) was applied to separate the independent source components,
followed by Fourier and time-frequency analysis. For quantitative EEG analysis, we apply several statistical complexity measures
to the EEG signals and evaluate the differences between two groups of patients: the subjects in deep coma, and the subjects
who were categorized as brain death. We report statistically significant differences of quantitative statistics with real-life
EEG recordings in such a clinical study, and we also present interpretation and discussions on the preliminary experimental
results.
相似文献
Zhe ChenEmail: |
164.
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166.
John D. Baniecki Hideshi Yamaguchi Catalin Harnagea Dan Ricinschi Zongquan Gu Jonathan E. Spanier Takashi Yamazaki Hiroyuki Aso 《Liver Transplantation》2019,9(28)
Achieving high oxygen evolution reaction (OER) activity while maintaining performance stability is a key challenge for designing perovskite structure oxide OER catalysts, which are often unstable in alkaline environments transforming into an amorphous phase. While the chemical and structural transformation occurring during electrolysis at the electrolyte–catalyst interface is now regarded as a crucial factor influencing OER activity, here, using La0.7Sr0.3CoO3?δ (LSCO) as an active OER catalyst, the critical influence of buried layers on the oxidation current stability in nanoscopically thin, chemically and structurally evolving, catalyst layers is revealed. The use of epitaxial thin films is demonstrated to engineer both depletion layer widths and chemical stability of the catalyst support structure resulting in heterostructured anodes that maintain facile transport kinetics across the electrolyte–anode interface for atomically thin (2–3 unit cells) LSCO catalyst layers and greatly enhanced oxidation current stability as the perovskite structure OER catalysts chemically and structurally transform. This work opens up an approach to design robust and active heterostructured anodes with dynamically evolving ultrathin OER electrocatalyst layers for future green fuel technologies such as conformal coatings of high‐density 3D anode topologies for water splitting. 相似文献
167.
168.
Contaminant Removal of Domestic Wastewater by Constructed Wetlands: Effects of Plant Species 总被引:9,自引:0,他引:9
Qiong Yang Zhang-He Chen Jian-Gang Zhao Bin-He Gu 《植物学报(英文版)》2007,49(4):437-446
A comparative study of the efficiency of contaminant removal between five emergent plant species and between vegetated and unvegetated wetlands was conducted in small-scale (2.0 m×1.0 m×0.7 m, lengthxwidthxdepth) constructed wetlands for domestic wastewater treatment in order to evaluate the decontaminated effects of different wetland plants. There was generally a significant difference in the removal of total nitrogen (TN) and total phosphorus (TP), but no significant difference in the removal of organic matter between vegetated and unvegetated wetlands. Wetlands planted with Canna indica Linn., Pennisetum purpureum Schum., and Phragmites communis Trin. had generally higher removal rates for TN and TP than wetlands planted with other species. Plant growth and fine root (root diameter ≤ 3 mm) biomass were related to removal efficiency. Fine root biomass rather than the mass of the entire root system played an important role in wastewater treatment. Removal efficiency varied with season and plant growth. Wetlands vegetated by P. purpureum significantly outperformed wetlands with other plants in May and June, whereas wetlands vegetated by P. communis and C. indica demonstrated higher removal efficiency from August to December. These findings suggest that abundance of fine roots is an important factor to consider in selecting for highly effective wetland plants. It also suggested that a plant community consisting of multiple plant species with different seasonal growth patterns and root characteristics may be able to enhance wetland performance. 相似文献
169.
H. A. Guénin 《Genetica》1951,25(1):157-182
Sans résumé
Avec 81 figures dans le texte 相似文献
170.