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Chen Ping Dai Chun-Hua Shi Zhi-Hao Wang Yi Wu Jian-Nong Chen Kang Su Jin-Yu Li Jian 《Apoptosis : an international journal on programmed cell death》2021,26(11-12):639-656
Apoptosis - Resistance to epidermal growth factor receptor-tyrosin kinase inhibitors (TKIs, e.g. icotinib) remains a major clinical challenge. Non-small cell lung cancer patients with wild-type... 相似文献
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Jibing Li Chunling Luo Dayi Zhang Xuan Zhao Yeliang Dai Xixi Cai Gan Zhang 《Environmental microbiology》2021,23(11):7042-7055
Rhizoremediation is a potential technique for polycyclic aromatic hydrocarbon (PAH) remediation; however, the catabolic pathways of in situ rhizosphere PAH degraders and the main factors driving PAH rhizoremediation remain unclear. To address these issues, stable-isotope-probing coupled with metagenomics and molecular ecological network analyses were first used to investigate the phenanthrene rhizoremediation by three different prairie grasses in this study. All rhizospheres exhibited a significant increase in phenanthrene removal and markedly modified the diversity of phenanthrene degraders by increasing their populations and interactions with other microbes. Of all the active phenanthrene degraders, Marinobacter and Enterobacteriaceae dominated in the bare and switchgrass rhizosphere respectively; Achromobacter was markedly enriched in ryegrass and tall fescue rhizospheres. Metagenomes of 13C-DNA illustrated several complete pathways of phenanthrene degradation for each rhizosphere, which clearly explained their unique rhizoremediation mechanisms. Additionally, propanoate and inositol phosphate of carbohydrates were identified as the dominant factors that drove PAH rhizoremediation by strengthening the ecological networks of soil microbial communities. This was verified by the results of rhizospheric and non-rhizospheric treatments supplemented with these two substances, further confirming their key roles in PAH removal and in situ PAH rhizoremediation. Our study offers novel insights into the mechanisms of in situ rhizoremediation at PAH-contaminated sites. 相似文献
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Yuchen Wang Jie Wu Wenjie Luo Hailiang Zhang Guohai Shi Yijun Shen Yao Zhu Chunguang Ma Bo Dai Dingwei Ye Yiping Zhu 《Cell death & disease》2021,12(7)
Bladder cancer is one of the most common malignant tumors in the urinary system. The development and improvement of treatment efficiency require the deepening of the understanding of its molecular mechanism. This study investigated the role of ALPK2, which is rarely studied in malignant tumors, in the development of bladder cancer. Our results showed the upregulation of ALPK2 in bladder cancer, and data mining of TCGA database showed the association between ALPK2 and pathological parameters of patients with bladder cancer. In vitro and in vivo experiments demonstrated that knockdown of ALPK2 could inhibit bladder cancer development through regulating cell proliferation, cell apoptosis, and cell migration. Additionally, DEPDC1A is identified as a potential downstream of ALPK2 with direct interaction, whose overexpression/downregulation can inhibit/promote the malignant behavioral of bladder cancer cells. Moreover, the overexpression of DEPDC1A can rescue the inhibitory effects of ALPK2 knockdown on bladder cancer. In conclusion, ALPK2 exerts a cancer-promoting role in the development of bladder cancer by regulating DEPDC1A, which may become a promising target to improve the treatment strategy of bladder cancer.Subject terms: Cancer models, Bladder cancer 相似文献
126.
利用光镜对叉蕨科7属30种植物叶表皮形态特征进行详细观察研究。结果显示:(1)叉蕨科30种植物的叶上表皮和下表皮细胞形状均为不规则型,垂周壁式样为深波状或浅波状,具单晶或针晶;上表皮细胞的长宽比为1.62~4.0,下表皮细胞的长宽比为1.63~3.06。(2)在30种植物中共观察到7种气孔器类型,分别为:极细胞型、腋下细胞型、聚合极细胞型、聚腋下细胞型、不等细胞型、无规则四细胞型和不规则型,每种植物分别具有4~7种气孔器类型,均为下生型气孔;气孔长宽比为1.22~1.91,气孔密度为8~76个/mm2,气孔指数为3.9%~25.7%。(3)基于气孔器类型组成进行聚类分析,可将30种植物分成3个类群。(4)对叶表皮形态特征分析认为,轴脉蕨属应介于叉蕨属和肋毛蕨属之间,且与叉蕨属关系更近;叉蕨属的范畴还有待进一步研究;支持将肋毛蕨属从叉蕨科中分离出来置于鳞毛蕨科,但不支持黄腺羽蕨属归入鳞毛蕨科。 相似文献
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利用生物信息学方法,从茶树(Camellia sinensis(L.)O.Ktze.)全基因组数据库中分析获得DELLA蛋白的家族成员,并对它们的系统进化关系、蛋白序列特征、基因表达特异性及其与茶树次生代谢物的相关性进行分析。结果显示:茶树基因组中共有5个DELLA基因,分别为:TEA009882(CsGAI)、TEA022818(CsRGA1)、TEA010112(CsRGL1)、TEA008736(CsRGL2)和TEA020933(CsRGL3);其编码的氨基酸数量在525~594之间,均定位于细胞核。该蛋白的二级和三级结构分析结果表明,茶树DELLA蛋白结构中含有大量的α螺旋及少量β转角结构。蛋白保守结构域分析结果显示该蛋白与拟南芥(Arabidopsis thaliana(L.)Heynh.)具有高度的同源性,均具有GRAS、DELLA等保守结构域。基因的表达特异性分析结果表明,在茶树不同组织部位中,TEA009882、TEA022818和TEA010112基因的表达量均较高,而TEA020933和TEA008736的表达量在各组织中均较低;茶树DELLA基因的表达受到干旱、NaCl、低温及茉莉酸甲酯等非生物逆境胁迫的调控,且其表达量与茶树次生代谢物的积累间存在相关性。推测茶树DELLA基因广泛参与了茶树生长发育及非生物逆境胁迫的响应,以及对次生代谢物生物合成过程的调控。 相似文献
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Myostatin, or growth and differentiation factor 8, is a member of the transforming growth factor-β superfamily; it functions as a negative regulator of skeletal muscle development and growth in mammals. In this study, single nucleotide polymorphisms in the 5′ regulatory region and exon 1 of the myostatin gene were detected by PCR–SSCP in the Bian, Jinghai, Youxi, and Arbor Acre chickens, and the associations of the polymorphisms with reproduction traits were analyzed. Seven SNPs (A326G, C334G, C1346T, G1375A, A1473G, G1491A, and G2283A) were found in the myostatin gene. Association analysis showed that the G2283A were significantly associated with reproduction traits. Bian chickens of the GG genotype had a greater age at first egg than those of the GA and AA genotypes (P < 0.01). Correspondingly, Bian chickens of the GA and AA genotypes had larger egg number at 300 days than those of the GG genotype (P < 0.05 and P < 0.01, respectively). Bian chickens of the AA genotype had significantly higher body weight at 300 days than those of the GG genotype (P < 0.05). These results suggested that the myostatin gene may have certain effects on reproduction traits other than merely as a negative regulator of skeletal muscle development and growth in mammals previously reported. 相似文献
129.
目的:研究蕨菜乙醇提取物的致突变作用,为蕨菜的开发利用提供一定依据;方法:制备蕨菜乙醇提取物,采用Ames试验方法,以50μg/皿敌克松作为诱变剂,分别添加提取物50、100、200、400、800μg/皿,统计回变菌落数;结果:受试物各剂量组回变菌落数均未超过自发回变菌落数的2倍,且无剂量-反应关系;结论:在本实验条件下,蕨菜乙醇提取物无致突变作用. 相似文献
130.
Yifei Dai 《Computer methods in biomechanics and biomedical engineering》2013,16(5):599-606
Generation of finite element (FE) meshes of vertebrae from computed tomography (CT) scans is labour intensive due to their geometric complexity. As such, techniques that simplify creation of meshes of vertebrae are needed to make FE analysis feasible for large studies and clinical applications. Techniques to obtain a geometric representation of bone contours from CT scans of vertebrae and construct a hexahedral mesh from the contours were developed. An automated edge detection technique was developed to identify surface contours of the vertebrae, followed by atlas based B-spline curve fitting to construct curves from the edge points. The method was automatic and robust to missing data, with a controllable degree of smoothing and interpolation. Parametric mapping was then used to generate nodes for each CT slice, which were connected between slices to obtain a hexahedral mesh. This method could be adapted for modelling a variety of orthopaedic structures. 相似文献