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Derivative of plant phenolic compound inhibits the type III secretion system of Dickeya dadantii via HrpX/HrpY two‐component signal transduction and Rsm systems
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35.
Liao Y Tang J Deng Q Deng Y Luo T Wang X Chen H Liu T Chen X Brody AL Hao W 《PloS one》2011,6(11):e26460
Background
Cigarette smoking continues to be the leading cause of preventable morbidity and mortality in China and other countries. Previous studies have demonstrated gray matter loss in chronic smokers. However, only a few studies assessed the changes of white matter integrity in this group. Based on those previous reports of alterations in white matter integrity in smokers, the aim of this study was to examine the alteration of white matter integrity in a large, well-matched sample of chronic smokers and non-smokers.Methodology/Principal Findings
Using in vivo diffusion tensor imaging (DTI) to measure the differences of whole-brain white matter integrity between 44 chronic smoking subjects (mean age, 28.0±5.6 years) and 44 healthy age- and sex-matched comparison non-smoking volunteers (mean age, 26.3±5.8 years). DTI was performed on a 3-Tesla Siemens scanner (Allegra; Siemens Medical System). The data revealed that smokers had higher fractional anisotropy (FA) than healthy non-smokers in almost symmetrically bilateral fronto-parietal tracts consisting of a major white matter pathway, the superior longitudinal fasciculus (SLF).Conclusion/Significance
We found the almost symmetrically bilateral fronto-parietal whiter matter changes in a relatively large sample of chronic smokers. These findings support the hypothesis that chronic cigarette smoking involves alterations of bilateral fronto-parietal connectivity. 相似文献36.
Inhibitory effect of Epimedium extract on S-adenosyl-L-homocysteine hydrolase and biomethylation 总被引:1,自引:0,他引:1
In the present paper, the inhibitory effect of Epimedium extract on the activity of S-adenosyl-L-homocysteine (AdoHcy) Hydrolase was studied. The results showed that Epimedium extract inhibited the activity of recombinant human AdoHcy hydrolase in a dose-dependent manner. This inhibitory effect was also observed in hepatic cell line 7701 and hepatoma HepG2, however, the effect in 7701 cells was more potent than in HepG2 cells. The extract could significantly reduce AdoMet/AdoHcy ratio in 7701 cells in a dose-dependent manner, suggesting reduced biomethylation level in 7701 cells. In contrast, it resulted in elevated AdoMet/AdoHcy ratio in the HepG2 cells. The result of MALDI-MS assay indicated that epimedin A and ikarisoside F from the extract could bind to AdoHcy hydrolase. The present data suggested that Epimedium extract could inhibit the activity of AdoHcy hydrolase, thus regulating the cellular biomethylation as well as reducing cellular Hcy level. These results will provide new clues to the mechanisms of Epimedium in curing of cardiovascular disease and regulating tumor cell growth. 相似文献
37.
Terada N Ohno N Yamakawa H Ohara O Liao X Baba T Ohno S 《Histochemistry and cell biology》2005,124(3-4):303-311
Protein 4.1 families have recently been established as potential organizers of an adherens system. In the adult mouse testis,
protein 4.1G (4.1G) localized as a line pattern in both basal and adluminal compartments of the seminiferous tubules, attaching
regions of germ cells and Sertoli cells. By double staining for 4.1G and F-actin, their localizations were shown to be different,
indicating that 4.1G was localized in a region other than the basal and apical ectoplasmic specializations, which formed the
Sertoli–Sertoli cell junction and Sertoli–spermatid junction, respectively. By electron microscopy, immunoreactive products
were seen exclusively on the cell membranes of Sertoli cells, attaching to the various differentiating germ cells. The immunolocalization
of cadherin was identical to that of 4.1G, supporting the idea that 4.1G may be functionally interconnected with adhesion
molecules. In an experimental mouse model of cadmium treatment, in which tight and adherens junctions of seminiferous tubules
were disrupted, the 4.1G immunostaining in the seminiferous tubules was dramatically decreased. These results indicate that
4.1G may have a basic adhesive function between Sertoli cells and germ cells from the side of Sertoli cells. 相似文献
38.
Wu M El-Kattan Y Lin TH Ghosh A Kumar VS Kotian PL Cheng X Bantia S Babu YS Chand P 《Nucleosides, nucleotides & nucleic acids》2005,24(10-12):1569-1585
Various C-1'-substituted acyclic N9 adenine nucleosides were prepared from 9-[(1-hydroxymethyl)(3-monomethoxytrityloxy)propyl]-N6-monomethoxytrityladenine. The hydroxymethyl was modified to the phosphonomethoxy derivative, and the 3-monomethoxytrityloxy was converted to hydroxyl, methoxy, azido, and amino. Other substituents, such as ethyl and ea-hydroxyethyl were also prepared. The resulting phosphonomethoxy derivatives were converted to prodrugs. 相似文献
39.
Ramasamy KS Amador RB Habib Q Rong F Han X Li DY Huang J Hong Z An H 《Nucleosides, nucleotides & nucleic acids》2005,24(10-12):1947-1970
The synthesis of pyrazolo[4,3-d]pyrimidine nucleoside library using solid-phase parallel synthesis methodology is described. Glycosylation of the trimethylsilyl (TMS) derivative of 1- and 2-(methyl)-1H and 2H-pyrazolo[4,3-d]pyrimidine-5,7-(4H, 6H)-dione (5) with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose in the presence of TMS triflate provided two novel protected nucleosides 6 and 7. The structures of 6 and 7 were assigned by 1H and 2D NMR experiments. Nucleosides 6 and 7 were then transformed to the key intermediates 12 and 15 respectively. Reaction of 12 and 15 with MMTCl resin in the presence of 2,6-lutidine afforded the necessary scaffolds B and C. Different amines (96) were introduced selectively by nucleophilic substitution on scaffolds B and C using solid-phase parallel semi-automated synthesizer. Cleavage of the products from the solid support with 30% HFIP in a parallel fashion yielded nucleoside libraries simultaneously, and they were analyzed and characterized by high-throughput LC-MS. 相似文献
40.
A cellular automata model to simulate penicillin fed-batch fermentation process(CAPFM)was established in this study,based on a morphologically structured dynamic penicillin production model,that is in turn based on the growth mechanism of penicillin producing microorganisms and the characteristics of penicillin fed-batch fermentation.CAPFM uses the three-dimensional cellular automata as a growth space,and a Moore-type neighborhood as the cellular neighborhood.The transition roles of CAPFM are designed based on mechanical and structural kinetic models of penicillin batch-fed fermentation processes.Every cell of CAPFM represents a single or specific number of penicillin producing microorganisms,and has various state.The simulation experimental results show that CAPFM replicates the evolutionary behavior of penicillin batch-fed fermentation processes described by the structured penicillin production kinetic model accordingly. 相似文献