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991.
Pyrogallol (PG) is a polyphenol compound and has been known to be an O generator. We evaluated the effects of PG on the growth of human pulmonary A549 cells in relation to the cell cycle and apoptosis. Treatment with 50 or 100 μM PG significantly inhibited the cell growth of A549 for 72 h. DNA flow cytometric analysis indicated that PG slightly induced a G1 phase arrest of the cell cycle at 24 or 48 h, but did not induce the specific cell cycle arrest at 72 h. Intracellular GSH depletion was observed in PG‐treated cells. PG induced apoptosis in A549 cells, as evidenced by sub‐G1 cells, annexin V staining cells, and the loss of mitochondrial membrane potential (Δ Ψm). The intracellular ROS (reactive oxygen species) level including O increased in PG‐treated A549 cells at 24 and 48 h, and persisted at 72 h. The changes in GSH as well as ROS levels by PG affected the cell viability in A549 cells. In conclusion, PG inhibited the growth of human pulmonary A549 cells by inducing cell cycle arrest as well as triggering apoptosis. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:36–42, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20263  相似文献   
992.
Alterations of nitric oxide contribute to post‐flight orthostatic intolerance. The aim of this study was to investigate the changes of inducible nitric oxide synthase (iNOS) and the mechanisms underlying regulation of iNOS by simulated microgravity in human umbilical vein endothelial cells (HUVECs). Clinorotation, a simulated‐model of microgravity, increased iNOS expression and promoter activity in HUVECs. The transactivations of NF‐κB and AP‐1 were suppressed by 24 h clinorotation. A key role for AP‐1, but not NF‐κB in the regulation of iNOS was shown. (1) PDTC, a NF‐κB inhibitor, had no effect on clinorotation upregulation of iNOS. (2) SP600125, a JNK‐specific inhibitor, which resulted in inhibition of AP‐1 activity, enhanced the iNOS expression and promoter activity in clinorotation. (3) Overexpression of AP‐1 remarkably attenuated the upregulation effect of clinorotation. These findings indicate that clinorotation upregulates iNOS in HUVECs by a mechanism dependent on suppression of AP‐1, but not NF‐κB. These results support a key role for AP‐1 in the signaling of postflight orthostatic intolerance. J. Cell. Biochem. 107: 357–363, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
993.
Asthma is a complex inflammatory disease of airways. A network of reciprocal interactions between inflammatory cells, peptidic mediators, extracellular matrix components, and proteases is thought to be involved in the installation and maintenance of asthma‐related airway inflammation and remodeling. To date, new proteic mediators displaying significant activity in the pathophysiology of asthma are still to be unveiled. The main objective of this study was to uncover potential target proteins by using surface‐enhanced laser desorption/ionization‐time of flight‐mass spectrometry (SELDI‐TOF‐MS) on lung samples from mouse models of allergen‐induced airway inflammation and remodeling. In this model, we pointed out several protein or peptide peaks that were preferentially expressed in diseased mice as compared to controls. We report the identification of different five proteins: found inflammatory zone 1 or RELMα (FIZZ‐1), calcyclin (S100A6), clara cell secretory protein 10 (CC10), Ubiquitin, and Histone H4.  相似文献   
994.
A major barrier to the physical characterization and structure determination of membrane proteins is low yield in recombinant expression. To address this problem, we have designed a selection strategy to isolate mutant strains of Escherichia coli that improve the expression of a targeted membrane protein. In this method, the coding sequence of the membrane protein of interest is fused to a C‐terminal selectable marker, so that the production of the selectable marker and survival on selective media is linked to expression of the targeted membrane protein. Thus, mutant strains with improved expression properties can be directly selected. We also introduce a rapid method for curing isolated strains of the plasmids used during the selection process, in which the plasmids are removed by in vivo digestion with the homing endonuclease I‐CreI. We tested this selection system on a rhomboid family protein from Mycobacterium tuberculosis (Rv1337) and were able to isolate mutants, which we call EXP strains, with up to 75‐fold increased expression. The EXP strains also improve the expression of other membrane proteins that were not the target of selection, in one case roughly 90‐fold.  相似文献   
995.
Betel nut chewing has been reported to increase the risk of cardiovascular disease and all‐cause mortality. The reason is unclear. In this study, we investigated the association between betel nut chewing and general obesity (BMI ≥25 kg/m2) and central obesity (waist circumference (WC) ≥90 cm). A total of 1,049 male subjects, aged ≥40 years, were recruited from Taichung city in Taiwan in 2004. The relationships between betel nut chewing and general and central obesity were studied by multiple linear and logistic regression analyses. The prevalence of current and former betel nut chewing was 7.0 and 10.5% in our male Taiwanese cohort. Current/former betel nut chewers had a higher prevalence of general and central obesity when compared with individuals who had never chewed betel nut. Adjusted for age, diabetes, hypertension, lipids, smoking, alcohol drinking, physical activity, income, and education level, the odds ratios (ORs; 95% confidence intervals) of general and central obesity among the lower consumption of betel nut chewers were 1.78 (1.07, 2.96) and 1.19 (0.70, 2.02), respectively, compared to 2.01 (1.18, 3.41) and 1.89 (1.10, 3.23), respectively, among higher consumption chewers compared to individuals who had never chewed betel nut. The increasing ORs of general and central obesity with higher betel nut consumption revealed dose–response effects. Using multiple linear regression analyses, after adjusting for potential confounders, betel nut consumption was statistically significantly associated with BMI and WC. In conclusion, betel nut chewing was independently associated with general and central obesity in Taiwanese men. Dose–response effects of the association between betel nut consumption and general obesity as well as central obesity were found.  相似文献   
996.

Background  

During infection and inflammation, circulating blood monocytes migrate from the intravascular compartments to the extravascular compartments, where they mature into tissue macrophages. The maturation process prepares the cells to actively participate in the inflammatory and immune responses, and many factors have been reported to be involved in the process. We found in our study that CD147 played a very important role in this process.  相似文献   
997.
Oresitrophe and Mukdenia (Saxifragaceae) are epilithic sister genera used in traditional Chinese medicine. The taxonomy of Mukdenia, especially of M. acanthifolia, has been controversial. To address this, we produced plastid and mitochondrial data using genome skimming for Mukdenia acanthifolia and Mukdenia rossii, including three individuals of each species. We assembled complete plastomes, mitochondrial CDS and nuclear ribosomal ETS/ITS sequences using these data. Comparative analysis shows that the plastomes of Mukdenia and Oresitrophe are relatively conservative in terms of genome size, structure, gene content, RNA editing sites and codon usage. Five plastid regions that represent hotspots of change (trnH-psbA, psbC-trnS, trnM-atpE, petA-psbJ and ccsA-ndhD) are identified within Mukdenia, and six regions (trnH-psbA, petN-psbM, trnM-atpE, rps16-trnQ, ycf1 and ndhF) contain a higher number of species-specific parsimony-informative sites that may serve as potential DNA barcodes for species identification. To infer phylogenetic relationships between Mukdenia and Oresitrophe, we combined our data with published data based on three different datasets. The monophyly of each species (Oresitrophe rupifraga, M. acanthifolia and M. rossii) and the inferred topology ((M. rossii, M. acanthifolia), O. rupifraga) are well supported in trees reconstructed using the complete plastome sequences, but M. acanthifolia and M. rossii did not form a separate clade in the trees based on ETS + ITS data, while the mitochondrial CDS trees are not well-resolved. We found low recovery of genes in the Angiosperms353 target enrichment panel from our unenriched genome skimming data. Hybridization or incomplete lineage sorting may be the cause of discordance between trees reconstructed from organellar and nuclear data. Considering its morphological distinctiveness and our molecular phylogenetic results, we strongly recommend that M. acanthifolia be treated as a distinct species.  相似文献   
998.
Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.  相似文献   
999.
1000.
Chlorogenic (5‐CQA), 1,5‐, 3,5‐, 4,5‐ and 3,4‐dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus‐christi L., I. bifrons L., I. aschersoniana Janka var. aschersoniana, I. ensifolia L., I. conyza (Griess .) DC. and I. germanica L. by HPLC analysis. The amount of 5‐CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5‐DCQA (4.05–55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5‐DCQA, 4,5‐DCQA and 3,4‐DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92±0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41±0.55 %). I. bifrons extract was found to be the most active sample against ABTS.+ (TEAC 0.257±0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 μg/mL toward non‐cancer (MDCK II) and cancer (A 549) cells.  相似文献   
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