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151.
Zhongyin Yang Chen Li Chao Yan Jianfang Li Min Yan Bingya Liu Zhenggang Zhu Yingli Wu Qinlong Gu 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):181-192
The kinesin family member 14 (KIF14) is a potential oncogene and is involved in the metastasis of various cancers. Nevertheless, its function in gastric cancer (GC) remains poorly defined. The expression of KIF14 was examined in GC cell lines and a clinical cohort of GC specimens by qPCR, western blotting and immunohistochemistry (IHC) staining. The relationship between KIF14 expression and the clinicopathological features was analyzed. The effect of KIF14 on cell proliferation, colony formation, invasion and migration were investigated in vitro and in vivo. The expression of KIF14 was significantly increased in the GC tissues and cell lines. High KIF14 expression was associated with tumor stage, tumor-node-metastasis (TNM) stage and metastasis. KIF14 was an independent prognostic factor for the overall survival of GC, and a higher expression of KIF14 predicted a poorer survival. KIF14 silencing resulted in attenuated proliferation, invasion and migration in human gastric cancer cells, whereas KIF14 ectopic expression facilitated these biological abilities. Notably, the depressed expression of KIF14 inhibited Akt phosphorylation, while overexpressed KIF14 augmented Akt phosphorylation. Additionally, there was a significant correlation between the expression of KIF14 and p?Akt in GC tissues. Importantly, the proliferation, invasion and migration of the GC cells, which was promoted by KIF14 overexpression, was abolished by the Akt inhibitor MK-2206, while Akt overexpression greatly rescued the effects induced by KIF14 knockdown. Our findings are the first to demonstrate that KIF14 is overexpressed in GC, is correlated with poor prognosis and plays a crucial role in the progression and metastasis of GC. 相似文献
152.
Xiaowei Wei Wei Ma Hui Gu Dan Liu Wenting Luo Songying Cao Shanshan Jia Tianchu Huang Yiwen He Yuzuo Bai Weilin Wang Zhengwei Yuan 《Cell proliferation》2023,56(2)
ObjectivesSpina bifida aperta (SBA) is one of the most common neural tube defects. Neural injury in SBA occurs in two stages involving failed neural tube closure and progressive degeneration through contact with the amniotic fluid. We previously suggested that intra‐amniotic bone marrow‐derived mesenchymal stem cell (BMSC) therapy for fetal rat SBA could achieve beneficial functional recovery through lesion‐specific differentiation. The aim of this study is to examine whether the amniotic fluid microenvironment can be improved by intra‐amniotic BMSC transplantation.MethodsThe intra‐amniotic BMSC injection was performed using in vivo rat fetal SBA models. The various cytokine expressions in rat amniotic fluid were screened by protein microassays. Intervention experiments were used to study the function of differentially expressed cytokines.ResultsA total of 32 cytokines showed significant upregulated expression in the BMSC‐injected amniotic fluid. We focused on Activin A, NGF, BDNF, CNTF, and CXCR4. Intervention experiments showed that the upregulated Activin A, NGF, BDNF, and CNTF could inhibit apoptosis and promote synaptic development in fetal spinal cords. Inhibiting the activity of these factors weakened the anti‐apoptotic and pro‐differentiation effects of transplanted BMSCs. Inhibition of CXCR4 activity reduced the engraftment rate of BMSCs in SBA fetuses.ConclusionBMSC transplantation can improve the amniotic fluid environment, and this is beneficial for SBA repair.In utero intra‐amniotic BMSC or PBS microinjection in the E15 fetuses was performed in E15 rat fetuses with spina bifida aperta, and amniotic fluid was collected at E21 for protein array detection. Venn diagram shows the relationship of three biological processes (GO: 0030335, 0048699, and 0043524) and the attribution of differentially expressed proteins. Comparative analysis of five proteins with the largest fold changes in the process of generation of neurons. 相似文献
153.
Yang Liu Yoshifumi Baba Takatsugu Ishimoto Xi Gu Jun Zhang Daichi Nomoto Kazuo Okadome Hideo Baba Peng Qiu 《International journal of biological sciences》2022,18(10):4101
The impact of the gut microbiome on host health is becoming increasingly recognized. To date, there is growing evidence that the complex characteristics of the microbial community play key roles as potential biomarkers and predictors of responses in cancer therapy. Many studies have shown that altered commensal bacteria lead to cancer susceptibility and progression in diverse pathways. In this review, we critically assess the data for gut microbiota related to gastrointestinal cancer, including esophageal, gastric, pancreatic, colorectal cancer, hepatocellular carcinoma and cholangiocarcinoma. Importantly, the underlying mechanisms of gut microbiota involved in cancer occurrence, prevention and treatment are elucidated. The purpose of this review is to provide novel insights for applying this understanding to the development of new therapeutic strategies in gastrointestinal cancer by targeting the microbial community. 相似文献
154.
不同生态型摩西球囊霉菌株对棉花耐盐性的影响 总被引:6,自引:0,他引:6
在盆栽条件下研究了4个NaCl水平下(0、1、2和3g/kg)接种丛枝菌根真菌Glomus mosseae的2个菌株M1和M2对棉花耐盐性的影响。M1自非盐渍土壤分离,M2自盐渍土壤分离。结果表明,不同盐水平下2个菌株对棉花根系的侵染率为20%~40%,M2的侵染率高于M1;这两个菌株对棉花在盐胁迫环境下的生长状况都有一定的促进,其中Ml的促进作用明显大于M2的,并且在NaCl水平为2和3g/kg时,两菌株对棉花生长的效应之间的差异达到极显著水平。进一步的分析表明两菌株对植株吸收矿质元素的作用方面存在一定差异。接种M1的植株含磷量在4个盐水平下均显著高于对照,而接种M2处理的植株含磷量只是在0和1g/kg NaCl时显著高于对照。在2和3g/kg NaCl时略低于对照,并显著低于接种M1处理的。在4个NaCl水平下,接种M1的植株钠和氯含量与对照没有显著差异;接种M2的植株氯含量在1~3g/kg 3个NaCl水平下、钠含量在2和3g/kg 2个NaCl水平下不仅显著高于对照,同时也显著高于接种M1的植株氯和钠含量。这些差异是M1和M2两菌株对提高棉花耐盐性作用大小不同的主要原因。上述结果说明不同生态型AM真菌菌株对植物的耐盐性的影响力不同,这与真菌自身的生物学特性有关。 相似文献
155.
TZP(TANDEM ZINC-FINGER/PLUS3)是近年来鉴定到的一个光信号转导途径新组分,在光介导的植物生长发育过程中发挥重要调控作用。TZP不仅负调控蓝光信号途径,参与光敏色素B(phyB)介导的开花调控过程,还参与调控phyA在体内的蛋白质磷酸化。对TZP生化活性和作用机制的深入研究,不仅有助于进一步完善光信号调控网络,也可为设计和培育具有耐密理想株型及高光效作物新品种提供理论依据。该文系统总结了TZP在植物光信号途径中发挥的重要调控作用,并提出未来TZP功能研究的重要问题。 相似文献
156.
增加降水对荒漠短命植物当年牧草生长及群落结构的影响 总被引:7,自引:1,他引:6
通过模拟降水增加试验研究了古尔班通古特荒漠常见短命植物盖度、密度及产量对水分输入量增加的响应.结果表明:尖喙牻牛儿苗、弯果胡卢巴、角果藜、琉苞菊、条叶庭芥及囊果苔草6种牧草生物量总和占总生物量的60%以上,是荒漠草原的优势牧草植物;供水量增加显著促进了角果藜、尖喙牻牛儿苗、弯果胡卢巴、条叶庭芥和琉苞菊5种牧草植物的个体生长;在自然降水的基础上,增加40mm和80mm供水使这5种植物生物产量比对照增加86%~230%.供水增加后,6种重要牧草对整个群落的生物贡献比例发生很大变化,只有角果藜和尖喙牻牛儿苗的贡献比例规律性增加,分别比对照增加了58%和11%,表明2种植物对供水增加的环境变化适应能力强;供水量增加促进了弯果胡芦巴、尖喙牻牛儿苗和角果藜3种植物N、P和K养分的吸收量;与此同时,供水量增加也显著提高了荒漠短命植物的密度和盖度.在降水增加的背景下,古尔班通古特沙漠南缘荒漠短命植物群落结构发生改变,植被盖度和群落净初级生产力提高,这对于防风固沙、稳定沙面,增加荒漠草原载畜能力有着积极的意义. 相似文献
157.
海南岛尖峰岭热带林自然保护区保存完好,森林植被类型齐全,生物资源极为丰富。蓟马(Thrips)在不同的植被类型中,有着不同的区系组成、生态分布和优势种群。热带半落叶季雨林中蓟马的特点是种类少,种群密度高,分布广;热带山地雨林中的蓟马则种类多,种群密度低并出现热带雨林的特有种,热带常绿季雨林中蓟马的特点介于上述的两者之间;山顶苔藓矮林中蓟马种类少,种群密度低。目前已鉴定的56种蓟马,具有东洋区昆虫的特点。 相似文献
158.
159.
Graham L. Cromar Jonathan R. Epp Ana Popovic Yusing Gu Violet Ha Brandon J. Walters James St. Pierre Xuejian Xiong John G. Howland Sheena A. Josselyn Paul W. Frankland John Parkinson 《PLoS neglected tropical diseases》2022,16(7)
During chronic infection, the single celled parasite, Toxoplasma gondii, can migrate to the brain where it has been associated with altered dopamine function and the capacity to modulate host behavior, increasing risk of neurocognitive disorders. Here we explore alterations in dopamine-related behavior in a new mouse model based on stimulant (cocaine)-induced hyperactivity. In combination with cocaine, infection resulted in heightened sensorimotor deficits and impairment in prepulse inhibition response, which are commonly disrupted in neuropsychiatric conditions. To identify molecular pathways in the brain affected by chronic T. gondii infection, we investigated patterns of gene expression. As expected, infection was associated with an enrichment of genes associated with general immune response pathways, that otherwise limits statistical power to identify more informative pathways. To overcome this limitation and focus on pathways of neurological relevance, we developed a novel context enrichment approach that relies on a customized ontology. Applying this approach, we identified genes that exhibited unexpected patterns of expression arising from the combination of cocaine exposure and infection. These include sets of genes which exhibited dampened response to cocaine in infected mice, suggesting a possible mechanism for some observed behaviors and a neuroprotective effect that may be advantageous to parasite persistence. This model offers a powerful new approach to dissect the molecular pathways by which T. gondii infection contributes to neurocognitive disorders. 相似文献
160.
基因瞬时表达是植物中研究目标基因功能的常用手段。在模式植物拟南芥(Arabidopsis thaliana)中, 相比原生质体和农杆菌介导的基因异源表达技术, 利用粒子轰击进行基因瞬时表达一直鲜有报道。其主要原因是拟南芥叶型相对较小、基因枪操作相对烦琐以及基因表达效率差异较大。该研究通过优化双管基因枪系统, 在营养生长旺盛的拟南芥莲座叶中实现GFP和GUS基因高效表达。同时, 通过GUS报告基因明确了坏死诱导因子BAX、Avh238和ATR13/Rpp13激发拟南芥细胞坏死的表型。但在本氏烟(Nicotiana benthamiana)中明显诱导细胞坏死的Avrblb1/RB基因对, 在拟南芥中却丧失了诱导细胞坏死的活性。由于双管基因枪系统每次轰击时设置平行对照, 可有效降低转化实验中的样本变异度, 为拟南芥及其突变体研究中准确评价基因功能和高通量筛选目标基因提供新的技术参考。 相似文献