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941.
Gibbings S Elkins ND Fitzgerald H Tiao J Weyman ME Shibao G Fini MA Wright RM 《The Journal of biological chemistry》2011,286(2):961-975
The protective effects of pharmacological inhibitors of xanthine oxidoreductase (XOR) have implicated XOR in many inflammatory diseases. Nonetheless, the role played by XOR during inflammation is poorly understood. We previously observed that inhibition of XOR within the inflammatory mononuclear phagocytes (MNP) prevented neutrophil recruitment during adoptive transfer demonstrating the role of XOR in MNP-mediated neutrophil recruitment. To further explore the role of XOR in the inflammatory state of MNP, we studied MNP isolated from inflammatory lungs combined with analyses of MNP cell lines. We demonstrated that XOR activity was increased in inflammatory MNP following insufflation of Th-1 cytokines in vivo and that activity was specifically increased by MNP differentiation. Inhibition of XOR reduced levels of CINC-1 secreted by MNP. Expression of peroxisome proliferator-activated receptor γ (PPARγ) in purified rat lung MNP and MNP cell lines reflected both the presence of PPARγ isoforms and PPARγ SUMOylation, and XOR inhibitors increased levels of SUMO-PPARγ in MNP cell lines. Both ectopic overexpression of XOR cDNA and uric acid supplementation reduced SUMO-PPARγ in MNP cells. Levels of the M2 markers CD36, CD206, and arginase-1 were modulated by uric acid and oxonic acid, whereas siRNA to SUMO-1 or PIAS-1 also reduced arginase-1 in RAW264.7 cells. We also observed that HIF-1α was increased by XOR inhibitors in inflammatory MNP and in MNP cell lines. These data demonstrate that XOR promotes the inflammatory state of MNP through effects on chemokine expression, PPARγ SUMOylation, and HIF-1α and suggest that strategies for inhibiting XOR may be valuable in modulating lung inflammatory disorders. 相似文献
942.
Roohollah Abbasi Maedeh Mashhadikhan Mehdi Abbasi Bahram Kiabi 《生态学杂志》2008,27(5):797-802
Vespidae is one of the major families of Hymenoptera with more than 115000 described species. In the present paper, Simpson and Shannon-Wiener diversity indices, Simpson,Camargo, Smith and Wilson, and modified Nee evenness indices, and richness index based on rarefaction method were adopted to study the biodiversity of vespid wasps in spatial and temporal dimensions in northern Zanjan Province of Iran. In spatial dimension, Zanjan and Gilvan showed the highest and the lowest species diversity, evenness, and richness, respectively; while in tem-poral dimension, 16 July-6 August showed the highest species diversity and richness, and 18 May -27 May and 23 August -2 September showed the highest and the lowest species evenness,respectively. Significant differences in species abundance between localities of study area were observed by Kruskal-Wallis nonparametric test. 相似文献
943.
MOTIVATION: BLAST programs are very efficient in finding similarities for sequences. However for large datasets such as ESTs, manual extraction of the information from the batch BLAST output is needed. This can be time consuming, insufficient, and inaccurate. Therefore implementation of a parser application would be extremely useful in extracting information from BLAST outputs. RESULTS: We have developed a java application, Batch Blast Extractor, with a user friendly graphical interface to extract information from BLAST output. The application generates a tab delimited text file that can be easily imported into any statistical package such as Excel or SPSS for further analysis. For each BLAST hit, the program obtains and saves the essential features from the BLAST output file that would allow further analysis. The program was written in Java and therefore is OS independent. It works on both Windows and Linux OS with java 1.4 and higher. It is freely available from: http://mcbc.usm.edu/BatchBlastExtractor/ 相似文献
944.
Synthesis,Biological Evaluation,and Molecular Docking Studies of Novel 4‐[4‐Arylpyridin‐1(4H)‐yl]benzoic Acid Derivatives as Anti‐HIV‐1 Agents 下载免费PDF全文
Saghi Sepehri Sepehr Soleymani Rezvan Zabihollahi Mohammad R. Aghasadeghi Mehdi Sadat Lotfollah Saghaie Afshin Fassihi 《化学与生物多样性》2017,14(12)
The structural similarities between N1 substituted 1,4‐dihydropyridines and the known gp41 inhibitors, NB ‐2 and NB ‐64 , were considered in the current research for the design of some novel anti‐HIV‐1 agents. A series of novel 4‐[4‐arylpyridin‐1(4H)‐yl]benzoic acid derivatives were synthesized and after a comprehensive structural elucidation were screened for in vitro anti‐HIV‐1 activity. Most of the tested compounds displayed moderate to good inhibitory activity against HIV‐1 growth and were evaluated for in vitro cytotoxic activity using XTT assay at the concentration of 100 μm . Among the tested compounds, 1c , 1d and 1e showed potent anti‐HIV‐1 activity against P24 expression at 100 μm with inhibition percentage of 84.00%, 76.42% and 80.50%, respectively. All the studied compounds possessed no significant cytotoxicity on MT‐2 cell line. The binding modes of these compounds to gp41 binding site were determined through molecular docking study. Docking studies proved 1a as the most potent compound and binding maps exhibited that the activities might be attributed to the electrostatic and hydrophobic interactions and additional H‐bonds with the gp41 binding site. The Lipinski's ‘rule of five’ and drug‐likeness criteria were also calculated for the studied compounds. All derivatives obeyed the Lipinski's ‘rule of five’ and had drug‐like features. The findings of this study suggest that novel 4‐[4‐arylpyridin‐1(4H)‐yl]benzoic acid might be a promising scaffold for the discovery and development of novel anti‐HIV‐1 agents. 相似文献
945.
Marcos E. Buzanskas Daniela A. Grossi Ricardo V. Ventura Flávio S. Schenkel Mehdi Sargolzaei Sarah L. C. Meirelles Fabiana B. Mokry Roberto H. Higa Maurício A. Mudadu Marcos V. G. Barbosa. da Silva Simone C. M. Niciura Roberto A. A. Torres. Júnior Maurício M. Alencar Luciana C. A. Regitano Danísio P. Munari 《PloS one》2014,9(4)
Studies are being conducted on the applicability of genomic data to improve the accuracy of the selection process in livestock, and genome-wide association studies (GWAS) provide valuable information to enhance the understanding on the genetics of complex traits. The aim of this study was to identify genomic regions and genes that play roles in birth weight (BW), weaning weight adjusted for 210 days of age (WW), and long-yearling weight adjusted for 420 days of age (LYW) in Canchim cattle. GWAS were performed by means of the Generalized Quasi-Likelihood Score (GQLS) method using genotypes from the BovineHD BeadChip and estimated breeding values for BW, WW, and LYW. Data consisted of 285 animals from the Canchim breed and 114 from the MA genetic group (derived from crossings between Charolais sires and ½ Canchim + ½ Zebu dams). After applying a false discovery rate correction at a 10% significance level, a total of 4, 12, and 10 SNPs were significantly associated with BW, WW, and LYW, respectively. These SNPs were surveyed to their corresponding genes or to surrounding genes within a distance of 250 kb. The genes DPP6 (dipeptidyl-peptidase 6) and CLEC3B (C-type lectin domain family 3 member B) were highlighted, considering its functions on the development of the brain and skeletal system, respectively. The GQLS method identified regions on chromosome associated with birth weight, weaning weight, and long-yearling weight in Canchim and MA animals. New candidate regions for body weight traits were detected and some of them have interesting biological functions, of which most have not been previously reported. The observation of QTL reports for body weight traits, covering areas surrounding the genes (SNPs) herein identified provides more evidence for these associations. Future studies targeting these areas could provide further knowledge to uncover the genetic architecture underlying growth traits in Canchim cattle. 相似文献
946.
The exact resolution of large instances of combinatorial optimization problems, such as three dimensional quadratic assignment problem (Q3AP), is a real challenge for grid computing. Indeed, it is necessary to reconsider the resolution algorithms and take into account the characteristics of such environments, especially large scale and dynamic availability of resources, and their multi-domain administration. In this paper, we revisit the design and implementation of the branch and bound algorithm for solving large combinatorial optimization problems such as Q3AP on the computational grids. Such gridification is based on new ways to efficiently deal with some crucial issues, mainly dynamic adaptive load balancing and fault tolerance. Our new approach allowed the exact resolution on a nation-wide grid of a difficult Q3AP instance. To solve this instance, an average of 1,123 computing cores were used for less than 12 days with a peak of around 3,427 computing cores. 相似文献
947.
948.
Mehdi Najar Johanne Martel-Pelletier Jean Pierre Pelletier Hassan Fahmi 《World journal of stem cells》2020,12(12):1474-1491
Mesenchymal stromal cells (MSCs) have attracted great interest in the field of regenerative medicine. They can home to damaged tissue, where they can exert pro-regenerative and anti-inflammatory properties. These therapeutic effects involve the secretion of growth factors, cytokines, and chemokines. Moreover, the functions of MSCs could be mediated by extracellular vesicles (EVs) that shuttle various signaling messengers. Although preclinical studies and clinical trials have demonstrated promising therapeutic results, the efficiency and the safety of MSCs need to be improved. After transplantation, MSCs face harsh environmental conditions, which likely dampen their therapeutic efficacy. A possible strategy aiming to improve the survival and therapeutic functions of MSCs needs to be developed. The preconditioning of MSCs ex vivo would strength their capacities by preparing them to survive and to better function in this hostile environment. In this review, we will discuss several preconditioning approaches that may improve the therapeutic capacity of MSCs. As stated above, EVs can recapitulate the beneficial effects of MSCs and may help avoid many risks associated with cell transplantation. As a result, this novel type of cell-free therapy may be safer and more efficient than the whole cell product. We will, therefore, also discuss current knowledge regarding the therapeutic properties of MSC-derived EVs. 相似文献
949.
950.
Shakeri R Kamangar F Nasrollahzadeh D Nouraie M Khademi H Etemadi A Islami F Marjani H Fahimi S Sepehr A Rahmati A Abnet CC Dawsey SM Brennan P Boffetta P Malekzadeh R Majdzadeh R 《PloS one》2012,7(3):e32711