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61.
Joon Ki Hong Jung Eun Hwang Woo Sik Chung Kyun Oh Lee Young Ju Choi Sang Wan Gal Beom -Seok Park Chae Oh Lim 《Journal of Plant Biology》2008,51(5):347-353
Phytocystatins are plant cysteine proteinase inhibitors that regulate endogenous and heterologous cysteine proteinases of
the papain family. A cDNA encoding the phytocystatin BrCYS1 (Brassica rapa cysteine proteinase inhibitor 1 ) has been isolated from Chinese cabbage (B. rapa subsp.pekinensis) flower buds. In order to explore the role of this inhibitory enzyme, tobacco plants (Nicotiana tabacum L. cv. Samson) containing altered amounts of phytocystatin were generated by over-expressingBrCYS1 cDNA in either the sense or the antisense configuration. The resulting plants hadin vitro enzyme inhibitory activities that were over 10% of those detected in wild type plants. The transgenic plants exhibited retarded
seed germination and seedling growth and a reduced seed yield, whereas these properties were enhanced in antisense plants.
These data suggest that BrCYS1 participates in the control of seed germination, post-germination and plant growth by regulating
cysteine peptidase activity. 相似文献
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This study presents the results of a Europe-wide training and Quality Control (QC) exercise carried out within the framework of the European Aerobiology Society’s QC Working Group and European COST Action FA1203 entitled “sustainable management of Ambrosia artemisiifolia in Europe (SMARTER)” with the aim of ensuring that pollen counters in Europe are confident in the identification of Ambrosia pollen grains. A total of 69 analysts from 20 countries examined a test slide by light microscopy, which contained Ambrosia pollen and pollen from other Asteraceae that could be recorded in the atmosphere at the same time of year (i.e. Artemisia, Iva, and Xanthium). Daily average pollen concentrations produced by individual participants were compared with the assigned value and the bias was measured by z-score. Both the assigned value and standard deviation for proficiency testing were calculated following the consensus value principle (ISO13528:2005) from the results reported by all the participants in the test. It took a total of 531 days from when the exercise commenced until all 69 analysts reported their results. The most outliers were reported for Artemisia pollen concentrations followed by Xanthium and Iva. The poor results for Artemisia and Xanthium were probably caused by low concentrations on the test slide leading to larger bias due to the unequal distribution of pollen over the microscope slide. Participants performed the best in identifying and quantifying Ambrosia pollen. Performing inter-laboratory ring tests with the same sample is very time consuming and might not be appropriate for large-scale proficiency testing in aerobiology. Pollen with similar morphology should be included in the education process of aerobiologists. 相似文献
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M. Bueno Martínez E. Román Galán J. A. Galbis Pérez 《Nucleosides, nucleotides & nucleic acids》2013,32(2):227-244
Abstract Fusion of 2-trimethylsilylpyridine and tetra-O-acetyl-aldehydo-D-xylose or 2,3:4,5-di-O-isopropylidene-aldehydo-L-arabinose led, after removing of the protecting groups, to 2-(pentitol-1-yl)pyridines of D-gulo and D-ido or L-manno configurations. Dehydration of the sugar-chain with D-gulo and D-ido configurations gave the corresponding 2′,5′-anhydro derivatives, whereas 2-(5-O-isopropyl-L-manno-pentitol-1-yl)-pyridine was the only compound formed by dehydration of the sugar-chain with L-manno configuration. Structural proofs are based on 1H and 13C NMR spectra. 相似文献
66.
Paloma Cariñanos Jean Emberlin Carmen Galán Eugenio Dominguez-Vilches 《Aerobiologia》2000,16(3-4):339-346
Two of the most frequently used methods of pollen counting on slides from Hirst type traps are evaluated in this paper: the
transverse traverse method and the longitudinal traverse method. The study was carried out during June–July 1996 and 1997
on slides from a trap at Worcester, UK. Three pollen types were selected for this purpose: Poaceae, Urticaceae and Quercus. The statistical results show that the daily concentrations followed similar trends (p < 0.01, R-values between 0.78–0.96)
with both methods during the two years, although the counts were slightly higher using the longitudinal traverses method.
Significant differences were observed, however, when the distribution of the concentrations during 24 hour sampling periods
was considered. For more detailed analysis, the daily counts obtained with both methods were correlated with the total number
of pollen grains for the taxon over the whole slide, in two different situations: high and low concentrations of pollen in
the atmosphere. In the case of high concentrations, the counts for all three taxa with both methods are significantly correlated
with the total pollen count. In the samples with low concentrations, the Poaceae and Urticaceae counts with both methods are
significantly correlated with the total counts, but none of Quercus counts are. Consideration of the results indicates that both methods give a reasonable approximation to the count derived
from the slide as a whole. More studies need be done to explore the comparability of counting methods in order to work towards
a Universal Methodology in Aeropalynology.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
67.
High prevalence of pathogenic mutations in patients with early-onset dementia detected by sequence analyses of four different genes 总被引:5,自引:0,他引:5 下载免费PDF全文
Finckh U Müller-Thomsen T Mann U Eggers C Marksteiner J Meins W Binetti G Alberici A Hock C Nitsch RM Gal A 《American journal of human genetics》2000,66(1):110-117
Clinical differential diagnosis of early-onset dementia (EOD) includes familial Alzheimer disease (FAD) and hereditary prion disease. In both disease entities, postmortem brain histopathological examination is essential for unambiguous diagnosis. Mutations in the genes encoding the presenilins (PS1 and PS2) and amyloid precursor protein (APP) are associated with FAD, whereas mutations in the prion protein (PrP) gene are associated with prion disease. To investigate the proportion of EOD attributable to known genes, we prospectively (i.e., antemortem) screened these four genes for mutations by sequencing genomic PCR products from patients with EOD before age 60 years. Family history for dementia was positive (PFH) in 16 patients, negative (NFH) in 17 patients, and unknown (UFH) in 3 patients. In 12 patients, we found five novel mutations (in PS1, F105L; in PS2, T122P and M239I; and in PrP, Q160X and T188K) and five previously reported mutations (in APP, in three patients who were most likely unrelated, V717I; in PS1, A79V and M139V; and in PrP, P102L and T183A) that are all considered to be disease causing. Of these 12 patients, 9 had PFH. This indicates a detection rate of 56% (9/16) in patients with PFH. We found two mutations (APP V717I) in two of the three UFH patients, and only one mutation (PrP T188K) in 1 of the 17 patients with NFH. We conclude that because of the lack of specific antemortem diagnostic markers for FAD and hereditary prion disease, all four genes should be included in a molecular diagnostic program in patients with EOD who had PFH. 相似文献
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Kamal El Farouki Emmanuel Lagarde Ludivine Orriols Manuel-Pierre Bouvard Benjamin Contrand Cédric Galéra 《PloS one》2014,9(12)