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981.
基于串联质谱的蛋白质组研究会产生海量的质谱数据,这些数据通常使用数据库搜索引擎进行鉴定分析,并根据肽段谱图匹配(PSM)反推真实的样品蛋白质.对于高通量蛋白质组数据的处理,其鉴定结果的可信是后续分析应用的前提,因此对鉴定结果的质量控制尤为重要,而基于目标-诱饵库(target-decoy)搜索策略的质量控制是目前应用最为广泛的方法.本文首先介绍了基于目标-诱饵库搜索策略搜库和质量控制的实施流程,然后综述了基于目标-诱饵库搜索策略的质量控制工具,并提出了目标-诱饵库搜索策略的不足及改善方法,最后对目标-诱饵库搜索策略进行了总结与展望. 相似文献
982.
983.
In metastatic breast cancer, the acquisition of malignant traits has been associated with the increased rate of cell growth and division, mobility, resistance to chemotherapy, and invasiveness. While screening for the key regulators of cancer metastasis, we observed that neurotrophin receptor TrkB is frequently overexpressed in breast cancer patients and breast cancer cell lines. Additionally, we demonstrate that TrkB expression and clinical breast tumor pathological phenotypes show significant correlation. Moreover, TrkB expression was significantly upregulated in basal-like, claudin-low, and metaplastic breast cancers from a published microarray database and in patients with triple-negative breast cancer, which is associated with a higher risk of invasive recurrence. Interestingly, we identified a new TrkB-regulated functional network that is important for the tumorigenicity and metastasis of breast cancer. We demonstrated that TrkB plays a key role in regulation of the tumor suppressors Runx3 and Keap1. A markedly increased expression of Runx3 and Keap1 was observed upon knockdown of TrkB, treatment with a TrkB inhibitor, and in TrkB kinase dead mutants. Additionally, the inhibition of PI3K/AKT activation significantly induced Runx3 and Keap1 expression. Furthermore, we showed that TrkB enhances metastatic potential and induces proliferation. These observations suggest that TrkB plays a key role in tumorigenicity and metastasis of breast cancer cells through suppression of Runx3 or Keap1 and that it is a promising target for future intervention strategies for preventing tumor metastasis and cancer chemoprevention. 相似文献
984.
985.
Mengfei Song Feng Cheng Jing Wang Qingzhen Wei Wenyuan Fu Xiaqing Yu Ji Li Jinfeng Chen Qunfeng Lou 《植物学报(英文版)》2019,61(9):1000-1014
Optimizing leaf shape is a major challenge in efforts to develop an ideal plant type. Cucumber leaf shapes are diverse; however, the molecular regulatory mechanisms underlying leaf shape formation are unknown. In this study, we obtained a round leaf mutant(rl) from an ethyl methanesulfonate-induced mutagenesis population. Genetic analysis revealed that a single recessive gene, rl, is responsible for this mutation. A modified Mut Map analysis combined linkage mapping identified a single nucleotide polymorphism within a candidate gene,Csa1 M537400, as the mutation underlying the trait.Csa1 M537400 encodes a PINOID kinase protein involved in auxin transport. Expression of Csa1 M537400 was significantly lower in the rl mutant than in wild type, and it displayed higher levels of IAA(indole-3-acetic acid) in several tissues. Treatment of wild-type plants with an auxin transport inhibitor induced the formation of round leaves,similar to those in the rl mutant. Altered expression patterns of several auxin-related genes in the rl mutant suggest that rl plays a key role in auxin biosynthesis,transport, and response in cucumber. These findings provide insight into the molecular mechanism underlying the regulation of auxin signaling pathways in cucumber,and will be valuable in the development of an ideal plant type. 相似文献
986.
目的:比较动力髋螺钉(DHS)与股骨近端髓内钉(PFNA)内固定治疗股骨粗隆间骨折患者的疗效及安全性和关节功能。方法:选取滁州市第一人民医院于2013年3月~2018年4月期间收治的160例股骨粗隆间骨折患者,根据内固定方式的不同将患者分为DHS组(n=80,采用DHS内固定)和PFNA组(n=80,采用PFNA内固定),比较两组临床疗效,采用髋关节功能Harris评分评价所有患者关节功能恢复情况,比较两组患者术前及术后相关指标,并观察患者术后并发症发生情况。结果:PFNA组患者临床总有效率为90.00%,高于DHS组患者的68.75%(P0.05)。两组患者Harris评分的优良率比较差异无统计学意义(P0.05)。PFNA组患者手术时间、卧床时间、骨折愈合时间、切口长度均短于DHS组(P0.05),术中出血量、术后引流量均少于DHS组(P0.05)。两组患者术后并发症总发生率比较无统计学差异(P0.05)。结论:DHS与PFNA内固定治疗股骨粗隆间骨折在术后关节功能恢复、安全性方面效果相当,但与DHS内固定治疗比较,PFNA内固定治疗的临床疗效更佳,手术时间更短,出血量更少,患者术后恢复更快,是治疗股骨粗隆间骨折较理想的手术方式。 相似文献
987.
988.
为了研究抑制素α亚基(inhibinα-subunit INH-α)对骨形态发生蛋白9(bone morphogenetic protein9,BMP9)诱导的间充质干细胞(mesenchymal stem cells,MSCs)成骨分化的影响,本研究采用细胞化学染色法检测第3天、第5天、第7天细胞中碱性磷酸酶(alkaline phosphatase,ALP)活性的变化。利用RT-PCR和Western blotting检测细胞中的成骨分化早期标志物(Runx2)和晚期标志物(OPN)的mRNA含量及蛋白表达水平。茜素红S染色法检测第21天细胞中的钙盐沉积变化。发现BMP9组ALP活性明显增高,INH-α组ALP活性与对照组相比无明显变化,但联合运用BMP9和INH-α组ALP活性较BMP9组明显降低。此外,BMP9组Runx2和OPN的mRNA含量和蛋白表达水平明显增高,而联用BMP9和INH-α组中的Runx2和OPN水平较BMP9组显著下降(p<0.01)。同样,在茜素红S染色实验中,BMP9组钙盐结节明显增多,染色深;而在联合运用BMP9和INH-α组钙盐结节较BMP9组明显减少,染色变浅。说明INH-α能够抑制BMP9诱导间充质干细胞成骨分化作用。 相似文献
989.
Kyu‐Won Kwak Hong‐Soo Choi Sung‐Hee Nam Myung‐Sae Han Eunsun Kim Kwanho Park Heui‐Sam Lee 《Entomological Research》2019,49(12):534-538
This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification. 相似文献
990.
Guoliang Wang Yuhua Xue Yanzi Wang Fei Dong Mei Shen Rongrong Zong Zuguo Liu Cheng Li 《Journal of cellular and molecular medicine》2019,23(6):4217-4228
Incomplete tear film spreading and eyelid closure can cause defective renewal of the ocular surface and air exposure‐induced epithelial keratopathy (EK). In this study, we characterized the role of autophagy in mediating the ocular surface changes leading to EK. Human corneal epithelial cells (HCECs) and C57BL/6 mice were employed as EK models, respectively. Transmission electron microscopy (TEM) evaluated changes in HCECs after air exposure. Each of these models was treated with either an autophagy inhibitor [chloroquine (CQ) or 3‐methyladenine (3‐MA)] or activator [Rapamycin (Rapa)]. Immunohistochemistry assessed autophagy‐related proteins, LC3 and p62 expression levels. Western blotting confirmed the expression levels of the autophagy‐related proteins [Beclin1 and mammalian target of rapamycin (mTOR)], the endoplasmic reticulum (ER) stress‐related proteins (PERK, eIF2α and CHOP) and the PI3K/Akt/mTOR signalling pathway‐related proteins. Real‐time quantitative PCR (qRT‐PCR) determined IL‐1β, IL‐6 and MMP9 gene expression levels. The TUNEL assay detected apoptotic cells. TEM identified autophagic vacuoles in both EK models. Increased LC3 puncta formation and decreased p62 immunofluorescent staining and Western blotting confirmed autophagy induction. CQ treatment increased TUNEL positive staining in HCECs, while Rapa had an opposite effect. Similarly, CQ injection enhanced air exposure‐induced apoptosis and inflammation in the mouse corneal epithelium, which was inhibited by Rapa treatment. Furthermore, the phosphorylation status of PERK and eIF2α and CHOP expression increased in both EK models indicating that ER stress‐induced autophagy promoted cell survival. Taken together, air exposure‐induced autophagy is indispensable for the maintenance of corneal epithelial physiology and cell survival. 相似文献