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991.
ObjectivesCrohn''s disease (CD) mesenteric adipose tissue (MAT) inflammation affects enteritis through the interaction between the mesentery and intestine, and we previously found that poorly differentiated mesenteric adipocytes were related to its inflammatory features. Pygopus2 (Pygo2) is a key negative regulator of adipocyte differentiation. We aimed to determine whether Pygo2 participates in CD mesenteric lesions and whether Pygo2 knockdown would be beneficial in a CD model (Il‐10 −/− mice).MethodsPygo2 expression in MAT from control and CD patients and Il‐10 −/− mice was measured by immunohistochemistry. Lentiviral transfection was used to regulate Pygo2 expression in Il‐10 −/− mice, and the effects on mesenteric adipocyte differentiation, inflammation, and dysfunction during spontaneous colitis, as well as the possible mechanism, were investigated.ResultsPygo2 expression was increased in MAT from CD patients and Il‐10 −/− mice, and its expression correlated with poor adipocyte differentiation and inflammation. Pygo2 knockdown significantly ameliorated colitis in Il‐10 −/− mice. Moreover, the downregulation of Pygo2 gene expression could promote adipocyte differentiation and inhibit adipocyte inflammation in vivo and in vitro, and the effects were at least partly mediated by the Axis inhibition protein 2 (Axin2)/glycogen synthase kinase 3 beta (GSK3β) pathway.ConclusionsThe increase in Pygo2 may be related to mesenteric adipocyte poor differentiation and inflammatory features of CD, and Pygo2 inhibition could alleviate CD‐like colitis by improving mesenteric lesions by regulating the Axin2/GSK3β pathway.

The increase in Pygopus2 (Pygo2) may be related to mesenteric adipocyte poor differentiation and inflammatory features of CD, and Pygo2 inhibition could alleviate adipocyte differentiation and mesenteric lesions by regulating the Axin2/GSK3β pathway.  相似文献   
992.
曾义  喻良  王曦  赵戈  黄忠 《现代生物医学进展》2019,19(20):3939-3942
目的:探讨急性缺血性脑卒中(AIS)患者血清半乳糖凝集素3(GAL3)、血清趋化因子12(CXCL12)水平与病情严重程度和预后的关系。方法:选取成都市第五人民医院于2016年2月~2018年9月期间接收的AIS患者138例为观察组,另选取同期来该院行健康体检的志愿者60例为对照组。其中观察组根据美国国立卫生研究所中风量表(NIHSS)评分分为轻症组(n=42,4分),中症组(n=61,4~15分),重症组(n=35,15分),根据改良RABKIN量表(m RS)评分分为预后良好组(n=82)和预后不良组(n=56)。比较对照组、观察组的血清GAL3、CXCL12水平,分析不同NIHSS得分、不同预后的血清GAL3、CXCL12水平,采用Pearson相关性分析血清GAL3、CXCL12水平与NIHSS评分、m RS评分的相关性。结果:观察组血清GAL3、CXCL12水平均显著高于对照组,差异有统计学意义(P0.05)。重症组、中症组AIS患者血清GAL3、CXCL12水平高于轻症组,且重症组高于中症组,差异有统计学意义(P0.05)。预后不良组的AIS患者血清GAL3、CXCL12水平均高于预后良好组,差异有统计学意义(P0.05)。Pearson相关性分析结果可知,血清GAL3、CXCL12水平与NIHSS评分、m RS评分均呈正相关(P0.05)。结论:AIS患者的血清GAL3、CXCL12水平均异常升高,且其升高程度与AIS患者病情严重程度及预后息息相关。  相似文献   
993.
Lysophosphatidic acid (LPA) is a potent agonist that exerts various cellular functions on many cell types through binding to its cognate G protein-coupled receptors (GPCRs). Although LPA induces NF-κB activation by acting on its GPCR receptor, the molecular mechanism of LPA receptor-mediated NF-κB activation remains to be well defined. In the present study, by using MEKK3-, TAK1-, and IKKβ-deficient murine embryonic fibroblasts (MEFs), we found that MEKK3 but not TAK1 deficiency impairs LPA and protein kinase C (PKC)-induced IκB kinase (IKK)-NF-κB activation, and IKKβ is required for PKC-induced NF-κB activation. In addition, we demonstrate that LPA and PKC-induced IL-6 and MIP-2 production are abolished in the absence of MEKK3 but not TAK1. Together, our results provide the genetic evidence that MEKK3 but not TAK1 is required for LPA receptor-mediated IKK-NF-κB activation.  相似文献   
994.
The finding that eukaryotic lanthionine synthetase C-like protein 1 (LanCL1) is a glutathione-binding protein prompted us to investigate the potential relationship between LanCL1 and cystathionine β-synthase (CBS). CBS is a trans-sulfuration enzyme critical for the reduced glutathione (GSH) synthesis and GSH-dependent defense against oxidative stress. In this study we found that LanCL1 bound to CBS in mouse cortex and HEK293 cells. Mapping studies revealed that the binding region in LanCL1 spans amino acids 158–169, and that in CBS contains N-terminal and C-terminal regulatory domains. Recombinant His-LanCL1 directly bound endogenous CBS from mouse cortical lysates and inhibited its activity. Overexpression of LanCL1 inhibited CBS activity in HEK293 cells. CBS activity is reported to be regulated by oxidative stress. Here we found that oxidative stress induced by H2O2 or glutamate lowered the GSH/GSSG ratio, dissociated LanCL1 from CBS, and elevated CBS activity in primary rat cortical neurons. Decreasing the GSH/GSSG ratio by adding GSSG to cellular extracts also dissociated LanCL1 from CBS. Either lentiviral knockdown of LanCL1 or specific disruption of the LanCL1-CBS interaction using the peptide Tat-LanCL1153–173 released CBS activity in neurons but occluded CBS activation in response to oxidative stress, indicating the major contribution of the LanCL1-CBS interaction to the regulation of CBS activity. Furthermore, LanCL1 knockdown or Tat-LanCL1153–173 treatment reduced H2O2 or glutamate-induced neuronal damage. This study implies potential therapeutic value in targeting the LanCL1-CBS interaction for neuronal oxidative stress-related diseases.  相似文献   
995.

Background

Gene expression microarray has been the primary biomarker platform ubiquitously applied in biomedical research, resulting in enormous data, predictive models, and biomarkers accrued. Recently, RNA-seq has looked likely to replace microarrays, but there will be a period where both technologies co-exist. This raises two important questions: Can microarray-based models and biomarkers be directly applied to RNA-seq data? Can future RNA-seq-based predictive models and biomarkers be applied to microarray data to leverage past investment?

Results

We systematically evaluated the transferability of predictive models and signature genes between microarray and RNA-seq using two large clinical data sets. The complexity of cross-platform sequence correspondence was considered in the analysis and examined using three human and two rat data sets, and three levels of mapping complexity were revealed. Three algorithms representing different modeling complexity were applied to the three levels of mappings for each of the eight binary endpoints and Cox regression was used to model survival times with expression data. In total, 240,096 predictive models were examined.

Conclusions

Signature genes of predictive models are reciprocally transferable between microarray and RNA-seq data for model development, and microarray-based models can accurately predict RNA-seq-profiled samples; while RNA-seq-based models are less accurate in predicting microarray-profiled samples and are affected both by the choice of modeling algorithm and the gene mapping complexity. The results suggest continued usefulness of legacy microarray data and established microarray biomarkers and predictive models in the forthcoming RNA-seq era.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-014-0523-y) contains supplementary material, which is available to authorized users.  相似文献   
996.
Zhang  Zhe  Fan  Junxia  Long  Chuannan  He  Bin  Hu  Zhihong  Jiang  Chunmiao  Li  Yongkai  Ma  Long  Wen  Jingshang  Zou  Xiaojin  Chen  Yuan  Ge  Zhenxiang  Zeng  Bin 《Journal of industrial microbiology & biotechnology》2019,46(12):1769-1780
Journal of Industrial Microbiology & Biotechnology - The ZRT, IRT-like protein (ZIP) family exists in many species and plays an important role in many biological processes, but little is known...  相似文献   
997.
The family of 14-3-3 proteins has emerged as critical regulators of diverse cellular responses under both physiological and pathological conditions. To gain insight into the molecular action of 14-3-3ζ in multiple myeloma (MM), we performed a systematic proteomic analysis of 14-3-3ζ-associated proteins. This analysis, recently developed by Matthias Mann, termed quantitative immunoprecipitation combined with knockdown (QUICK), integrates RNAi, SILAC, immunoprecipitation, and quantitative MS technologies. Quantitative mass spectrometry analysis allowed us to distinguish 14-3-3ζ-interacting proteins from background proteins, resulting in the identification of 292 proteins in total with 95 novel interactions. Three 14-3-3ζ-interacting proteins-BAX, HSP70, and BAG3-were further confirmed by reciprocal coimmunoprecipitations and colocalization analysis. Our results therefore not only uncover a large number of novel 14-3-3ζ-associated proteins that possess a variety of cellular functions, but also provide new research directions for the study of the functions of 14-3-3ζ. This study also demonstrated that QUICK is a useful approach to detect specific protein-protein interactions with very high confidence and may have a wide range of applications in the investigation of protein complex interaction networks.  相似文献   
998.
Plants have evolved sophisticated systems to cope with adverse environmental conditions such as cold, drought, and salinity. Although a number of stress response networks have been proposed, the role of plant apoplast in plant stress response has been ignored. To investigate the role of apoplastic proteins in the salt stress response, 10-day old rice plants were treated with 200mM NaCl for 1, 6 or 12h, and the soluble apoplast proteins of rice shoot stems were extracted for differential analysis, compared with untreated controls, by 2-D DIGE saturation labeling techniques. One hundred twenty-two significantly changed spots were identified by LC-MS/MS, and 117 spots representing 69 proteins have been identified. Of these proteins, 37 are apoplastic proteins according to the bioinformatic analysis. These proteins are mainly involved in the processes of carbohydrate metabolism, oxido-reduction, and protein processing and degradation. According to their functional categories and cluster analysis, a stress response model of apoplastic proteins has been proposed. These data indicate that the apoplast is important in plant stress signal reception and response.  相似文献   
999.
Y. C. Li    L. Z. An    Y. H. Ge    Y. Li    Y. Bi 《Journal of Phytopathology》2008,156(2):115-119
Ethanol‐dichloromethane crude extract from peel of pear (Pyrus bretschneideri Rehd. cv. Pingguoli) was separated by thin layer chromatographic plates and bioassayed with conidia of Alternaria alternata. The inhibition zones differed significantly in retention factor (Rf) at expanding stage, harvest time and after 100 days of cold storage. The compounds in the inhibition zones were isolated and identified with gas chromatography and mass spectroscopy. Palmitate methyl, oleic acid methyl, linolenic acid methyl and squalene were present at all stages. The concentration of these chemicals was the highest in expanding stage fruit peel and decreased rapidly with fruit development. It is suggested that these compounds may be the main antifungal compounds in the growing fruit. The phthalate alkyl esters occurred at relatively higher concentrations in pear peel at harvest and after 100 days of cold storage. Six phthalate alkyl esters were identified from peel of pear fruit after 100 days of cold storage. It is also supposed that these esters may be the antifungal compounds in postharvest pear.  相似文献   
1000.
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