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951.
SUZ12 is a novel putative oncogene promoting tumorigenesis in head and neck squamous cell carcinoma
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Yaping Wu Huijun Hu Wei Zhang Zhongwu Li Pengfei Diao Dongmiao Wang Wei Zhang Yanling Wang Jianrong Yang Jie Cheng 《Journal of cellular and molecular medicine》2018,22(7):3582-3594
The suppressor of zest 12 (SUZ12), one of the core polycomb repressive complex 2 (PRC2) components, has increasingly appreciated as a key mediator during human tumorigenesis. However, its expression pattern and oncogenic roles in head and neck squamous cell carcinoma (HNSCC) remain largely unexplored yet. Here, we sought to determine its expression pattern, clinicopathological significance and biological roles in HNSCC. Through data mining and interrogation from multiple publicly available databases, our bioinformatics analyses revealed that SUZ12 mRNA was significantly overexpressed in multiple HNSCC patient cohorts. Moreover, SUZ12 protein was markedly up‐regulated in primary HNSCC samples from our patient cohort as assessed by immunohistochemical staining and its overexpression significantly associated with cervical node metastasis and reduced overall and disease‐free survival. In the 4‐nitroquinoline 1‐oxide (4NQO)‐induced HNSCC mouse model, increased SUZ12 immunostaining was observed along with disease progression from epithelial hyperplasia to squamous cell carcinoma in tongue. Furthermore, shRNA‐mediated SUZ12 knock‐down significantly inhibited cell proliferation, migration and invasion in HNSCC cells, and resulted in compromised tumour growth in vivo. Collectively, our data reveal that SUZ12 might serve as a putative oncogene by promoting cell proliferation, migration and invasion, and also a novel biomarker with diagnostic and prognostic significance for HNSCC. 相似文献
952.
一株解磷细菌的筛选、鉴定及其溶磷培养条件的优化 总被引:3,自引:0,他引:3
从土壤作物根际筛选分离出的一株解磷能力较强的溶磷菌P0417,对其进行16S r DNA基因水平上的初步鉴定,测定其溶解磷的能力,并对该菌的溶磷培养基条件进行优化。结果表明,经序列分析,确定该菌株P0417为洋葱伯克霍尔德氏菌。且其溶磷能力与培养液p H呈显著相关性,当培养基条件为葡萄糖10 g/L、草酸铵0.5 g/L、Na Cl 1.0 g/L时,菌株P0417对Ca3(PO4)2盐培养基具有较好的解磷能力,其解磷能力可达791.84μg/m L。 相似文献
953.
Microbial fuel cells (MFCs) represent a new biological method for generating electricity directly from biodegradable compounds. Efficiency of MFCs using manure as substrate is generally low. This study proposed a new design by incorporating biocathodes into a three-chamber MFC, which yielded maximum power densities much higher than those reported in literature. The new design placed cylindrical anode chamber for easy stirring and two symmetrical cathodic chambers with reduced anode-cathode distance. The biocathodes were applied to reduce charge transfer resistance. Additionally, biocathode microbial community was cultured to enrich favorable microorganisms. With external loading of 100 Ω, the power densities for new biocathode MFC using 2, 4, 6, 8 and 10% total solids diary manure reached 7.85±1.0 W m(-3), 7.84±1.20 W m(-3), 8.15±0.20 W m(-3), 7.60±0.97 W m(-3) and 5.63±0.97 W m(-3), respectively. The pH drop as a result of manure hydrolysis limited the power output. To provide detailed information of the microbial community in the biocathode MFC, the 454-pyrosequencing technique was adopted. The Firmicutes, γ-, β-, α- and δ-Proteobacteria, Bacteroidetes and Actinobacteria were the major groups on the anode, while γ-, β-, and α-Proteobacteria, Bacteroidetes and Actinobacteria were the predominant groups on the cathode. 相似文献
954.
The interaction between viral protein and host actin facilitates the virus infection to host 总被引:1,自引:0,他引:1
Although the virus-host interaction has attracted extensive studies, the host proteins essential for virus infection remain largely unknown. To address this issue, the shrimp Penaeus stylirostris densovirus (PstDNV), belonging to the family Parvoviridae, was characterized. PstDNV, a single-stranded DNA virus with a 3.9-kb genome, encoded only three open reading frames (ORFs). Among the three viral proteins, the PstDNV ORF2-encoded protein was discovered to interact with the shrimp actin, suggesting that the host actin played a very important role in virus infection. The RNAi assays revealed that the ORF2-encoded protein was required for the PstDNV infection. The confocal evidence demonstrated that the interaction between the ORF2-encoded protein and actin was essential for the virus infection. Therefore our study indicated that the manipulation of the host actin cytoskeleton was a necessary strategy for viral pathogens to invade host cells. 相似文献
955.
人骨髓间充质干细胞在成年大鼠脑内的迁移及分化 总被引:27,自引:2,他引:27
骨髓间充质干细胞 (mesenchymalstemcells,MSCs)是目前备受关注的一类具有多向分化潜能的组织干细胞 ,体外可以分化为骨、软骨、脂肪等多种细胞。因此 ,MSCs是细胞治疗和基因治疗的种子细胞之一。为了探索MSCs的迁移和分化趋势 ,为帕金森病 (Parkinsondisease,PD)的干细胞治疗提供理论和实验依据 ,本实验将体外扩增并转染增强型绿色荧光蛋白 (enhancedgreenfluorescentprotein ,EGFP)的人骨髓MSCs注入PD大鼠脑内纹状体 ,观察了人骨髓MSCs在大鼠脑内的存活、迁移、分化以及注射MSCs前后大鼠的行为变化。结果表明 ,人骨髓MSCs在大鼠脑内可存活较长时间 ( 10周以上 ) ;随着时间的延长 ,MSCs迁移范围扩大 ,分布于纹状体、胼胝体、皮质以及脑内血管壁 ;免疫组化法检测证实MSCs在大鼠脑内表达人神经丝蛋白 (neurofilament,NF)、神经元特异性烯醇化酶 (neuron specificeno lase,NSE)以及胶质原纤维酸性蛋白 ( glialfibrillaryacidprotein ,GFAP) ;PD大鼠的异常行为有所缓解 ,转圈数由 8 86±2 0 9r/min下降到 4 87± 2 0 6r/min ,统计学分析P <0 0 5为差异显著。以上观察结果表明 ,骨髓MSCs有望成为治疗PD的种子细胞 相似文献
956.
Takeuchi H Mizuno T Zhang G Wang J Kawanokuchi J Kuno R Suzumura A 《The Journal of biological chemistry》2005,280(11):10444-10454
Recent studies suggest that excitotoxicity may contribute to neuronal damage in neurodegenerative diseases including Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis, and multiple sclerosis. Activated microglia have been observed around degenerative neurons in these diseases, and they are thought to act as effector cells in the degeneration of neural cells in the central nervous system. Neuritic beading, focal bead-like swellings in the dendrites and axons, is a neuropathological sign in epilepsy, trauma, ischemia, aging, and neurodegenerative diseases. Previous reports showed that neuritic beading is induced by various stimuli including glutamate or nitric oxide and is a neuronal response to harmful stimuli. However, the precise physiologic significance of neuritic beading is unclear. We provide evidence that neuritic beading induced by activated microglia is a feature of neuronal cell dysfunction toward neuronal death, and the neurotoxicity of activated microglia is mediated through N-methyl-d-aspartate (NMDA) receptor signaling. Neuritic beading occurred concordant with a rapid drop in intracellular ATP levels and preceded neuronal death. The actual neurite beads consisted of collapsed cytoskeletal proteins and motor proteins arising from impaired neuronal transport secondary to cellular energy loss. The drop in intracellular ATP levels was because of the inhibition of mitochondrial respiratory chain complex IV activity downstream of NMDA receptor signaling. Blockage of NMDA receptors nearly completely abrogated mitochondrial dysfunction and neurotoxicity. Thus, neuritic beading induced by activated microglia occurs through NMDA receptor signaling and represents neuronal cell dysfunction preceding neuronal death. Blockage of NMDA receptors may be an effective therapeutic approach for neurodegenerative diseases. 相似文献
957.
对塔里木沙漠公路防护林示范段老化衰败的沙拐枣林分进行平茬复壮试验,并对平茬后沙拐枣生长与土壤水盐分布进行动态监测.结果表明:两次平茬后,沙拐枣萌蘖株的株高、冠幅、地径和萌蘖数均迅速增加.与对照相比,平茬后第3年,沙拐枣萌蘖株的平均株高超过对照,冠幅和最大地径分别达到对照的92.0%和73.0%;萌蘖株的枝鲜质量、同化枝鲜质量、枝干质量、同化枝干质量、地上部分总鲜质量和总干质量分别达到对照的80.0%、115.0%、80.0%、116.0%、93.5%和88.0%.平茬4年后地上生物量达到甚至超过对照.平茬能增加土壤含水量,且影响达到极显著水平;平茬能降低土壤含盐量,但影响不显著.对老化衰败的沙拐枣林进行重复平茬,能增加其土壤含水量,降低根系分布层土壤含盐量,有效促进其复壮更新. 相似文献
958.
Sheng Peng Yan Zhang Jiannan Zhang Hua Wang Bingxu Ren 《Molecular biology reports》2011,38(1):453-460
The plasticity of the central nervous system helps form the basis for the neurobiology of learning and memory. Long-term potentiation
(LTP) is the main form of synaptic plasticity, reflecting the activity level of the synaptic information storage process,
and provides a good model to study the underlying mechanisms of learning and memory. The glutamate receptor-mediated signal
pathway plays a key role in the induction and maintenance of LTP, and hence the regulation of learning and memory. The progress
in the understanding of the glutamate receptors and related signal transduction systems in learning and memory research are
reviewed in this article. 相似文献
959.
水牛精子蛋白质组双向电泳体系的建立和优化 总被引:1,自引:0,他引:1
建立和优化一种适合水牛精子蛋白质组学研究的双向电泳技术。以水牛精子为研究对象,比较两种不同配方的裂解液,以及不同上样量对其2-DE图谱质量的影响。结果显示,以7 mol/L尿素、2 mol/L硫脲、4%CHAPS、1%DTT、0.5%Cocktail of protease inhibitors为裂解液,24 cm胶条上样量200μg时,可获得较好的精子总蛋白质2-DE图谱。运用ImageMaster 2-Dplatinum分析软件检测出约500个蛋白质点,蛋白质大部分分布在等电点5-7之间,分子量范围约40-90 kD。 相似文献
960.