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121.
Intestinal barrier dysfunction and intestinal inflammation interact in the progression of Crohn''s disease (CD). A recent study indicated that Epac‐2 protected the intestinal barrier and had anti‐inflammatory effects. The present study examined the function of Epac‐2 in CD‐like colitis. Interleukin‐10 gene knockout (Il10 −/−) mice exhibit significant spontaneous enteritis and were used as the CD model. These mice were treated with Epac‐2 agonists (Me‐cAMP) or Epac‐2 antagonists (HJC‐0350) or were fed normally (control), and colitis and intestinal barrier structure and function were compared. A Caco‐2 and RAW 264.7 cell co‐culture system were used to analyse the effects of Epac‐2 on the cross‐talk between intestinal epithelial cells and inflammatory cells. Epac‐2 activation significantly ameliorated colitis in mice, which was indicated by reductions in the colitis inflammation score, the expression of inflammatory factors and intestinal permeability. Epac‐2 activation also decreased Caco‐2 cell permeability in an LPS‐induced cell co‐culture system. Epac‐2 activation significantly suppressed nuclear factor (NF)‐κB/mitogen‐activated protein kinase (MAPK) signalling in vivo and in vitro. Epac‐2 may be a therapeutic target for CD based on its anti‐inflammatory functions and protective effects on the intestinal barrier.  相似文献   
122.
EIF1A encodes a translation initiation factor in eukaryocyte and aberrant expression of EIF1A is deemed to be associated with dysfunctions in intracranial diseases. The goal of this research was to explore the impacts of EIF1A on progression of human pituitary adenoma (PA). We employed immunohistochemistry to assess the expression of EIF1A in PA and para-carcinoma tissues. After constructing EIF1A-knockdown cell models via lentivirus infection, we examined cell proliferation through CCK-8 assay and Celigo cell counting assay. Flow cytometry was utilized to detect cell apoptosis and the migration ability of experimental cells was estimated using wound-healing assay and Transwell assay. The activity of the apoptosis-related factor, Caspase 3, was also examined via Caspase 3 activity assay. Lastly, in vivo xenograft mouse models were established to verify findings derived from in vitro cell models. Our results affirmed upregulation of EIF1A in PA cells and revealed that depletion of EIF1A could seriously limit cell proliferation and weaken the capacity of cell migration, and also enhance apoptosis of tumor cells. Mechanistically, degradation in cell growth mediated by EIF1A knockdown may involve in activation of MAPK signaling but inactivation of PI3K/AKT signaling pathway. This study indicates EIF1A plays a prominent role in facilitating tumor cell proliferation and migration which may further contribute to PA progression.Key words: EIF1A, Pituitary adenoma, Cell proliferation, Cell migration, MAPK  相似文献   
123.
The marine environment can be extremely dangerous, and the harm caused by marine organisms when they contact the human body can be especially harmful, even deadly. Contact includes stings, bites, wounds, and consumption as food. In this article, the characteristics of the common marine biological injuries are summarized, the major marine organisms causing damage in China’s marine waters are described, and injury prevention and treatment methods are discussed.  相似文献   
124.
组织转谷酰胺酶(transglutaminase 2,TGM2)是一种普遍存在的多功能蛋白,与不同细胞的粘附和肿瘤形成有关.有证据表明,TGM2参与了宿主细胞与病毒间的相互作用,但是对于流感病毒在细胞内增殖的影响还未有报道.为了探究MDCK细胞中TGM2对H1N1亚型流感病毒增殖的影响,本研究构建了TGM2过表达和敲除...  相似文献   
125.
126.
以毛茛科乌头属铁棒锤 (Aconitum pendulum N. Busch)2个品系‘蓝花铁棒锤’(‘WSYB1’)和‘黄花铁棒锤’(‘WSYY1’)为材料, 对其进行转录组测序(RNA-seq), 采用生物信息学方法鉴定其中可能存在的花柱S基因(self-incompatibility gene)和花粉S基因, 并...  相似文献   
127.
以牡丹江地区的白牛槭(Acer mandshuricum)、茶条槭(Acer tataricum subsp. ginnala.)、糖槭(Acer saccharum)、五角槭(Acer pictum subsp. mono)4种槭树为研究对象,分别于春季、夏季和秋季进行取样,测定叶片性状指标(叶厚度、气孔长度、气孔宽度、气孔密度、叶脉密度、比叶面积及色素质量分数),分析叶片各性状的季节变化趋势,并探讨色素与叶性状间在不同季节下的关系。结果如下(:1)4种槭树均表现为在夏季具有较高的叶厚度、较低的比叶面积和气孔密度,在秋季具较高的比叶面积和叶脉密度、较低的叶厚度。(2)4种槭树均为在夏季有较高的叶绿素a、b,在秋季色素质量分数均降低,季节变化区间分别为叶绿素a 77.40%~98.80%,叶绿素b 85.60%~99.53%,类胡萝卜素4.29%~78.52%。(3)色素与叶性状关系密切,季节动态下色素与比叶面积、气孔密度、叶脉密度正相关,与叶厚度、气孔长度、气孔宽度负相关(P<0.05),但不同季节相关性略有差异。4种彩叶植物的叶片在应对不同季节的气候条件时形成了不同的构建策略...  相似文献   
128.
三种粘结剂用于纵折牙粘结的微渗漏研究   总被引:2,自引:0,他引:2  
目的观察三种粘结材料的封闭性能,为折裂牙选择合适的粘结材料提供试验依据。方法选用健康前磨牙30颗,随机分为3组,制备成后牙纵折模型,分别用Clearfil SE Bond/AP—X(A组)、Super—Bond C&B(B组),Single Bond/F2000 Cmpomer(C组)进行粘结,在0.5%亚甲基蓝溶液中染色72h后,在电镜下观察染料渗透深度。结果扫描电镜下观察各组标本的粘结界面均有染料渗入,经单因素方差分析,A组与B组、C组有显著性差异,B组与C组之间无显著性差异。结论Clearfil SE Bond的封闭性能优于其它两组,但三种粘结剂均无法避免微渗漏的发生。  相似文献   
129.
ObjectivesThe rats are crucial animal models for the basic medical researches. Rat embryonic stem cells (ESCs), which are widely studied, can self‐renew and exhibit pluripotency in long‐term culture, but the mechanism underlying how they exit pluripotency remains obscure. To investigate the key modulators on pluripotency exiting in rat ESCs, we perform genome‐wide screening using a unique rat haploid system.Materials and MethodsRat haploid ESCs (haESCs) enable advances in the discovery of unknown functional genes owing to their homozygous and pluripotent characteristics. REX1 is a sensitive marker for the naïve pluripotency that is often utilized to monitor pluripotency exit, thus rat haESCs carrying a Rex1‐GFP reporter are used for genetic screening. Genome‐wide mutations are introduced into the genomes of rat Rex1‐GFP haESCs via piggyBac transposon, and differentiation‐retarded mutants are obtained after random differentiation selection. The exact mutations are elucidated by high‐throughput sequencing and bioinformatic analysis. The role of candidate mutation is validated in rat ESCs by knockout and overexpression experiments, and the phosphorylation of ERK1/2 (p‐ERK1/2) is determined by western blotting.ResultsHigh‐throughput sequencing analysis reveals numerous insertions related to various pathways affecting random differentiation. Thereafter, deletion of Thop1 (one candidate gene in the screened list) arrests the differentiation of rat ESCs by inhibiting the p‐ERK1/2, whereas overexpression of Thop1 promotes rat ESCs to exit from pluripotency.ConclusionsOur findings provide an ideal tool to study functional genomics in rats: a homozygous haploid system carrying a pluripotency reporter that facilitates robust discovery of the mechanisms involved in the self‐renewal or pluripotency of rat ESCs.

Differentiation of pluripotent rat embryonic stem cells (ESCs) in vitro is difficult to achieve for unknown mechanisms. Rat haploid ESCs (haESCs) have been validated as a powerful tool to target unknown functional genes and pathways based on homozygous genetic screening. Xu et al. utilized Rex1‐GFP labelled‐rat haESCs to conduct genome‐scale screening of genes modulating pluripotency exiting. Validation experiments showed that Thop1 (one of the screened out genes) played very important roles in the random differentiation of rat ESCs in vitro via modulating phosphorylation of ERK.  相似文献   
130.
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