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21.
Yoshiyuki Tsukamoto Shoichi Fumoto Tsuyoshi Noguchi Kazuyoshi Yanagihara Yuka Hirashita Chisato Nakada Naoki Hijiya Tomohisa Uchida Keiko Matsuura Ryoji Hamanaka Kazunari Murakami Masao Seto Masafumi Inomata Masatsugu Moriyama 《American journal of cancer research》2015,5(10):2998-3014
Previously, we have reported that gain at chromosome 20q13 is the most common genomic copy number aberration in gastric cancer (GC) (29/30 cases), and that among the genes located in this region, we have identified DDX27, whose expression level shows the highest correlation with genomic copy number, as a candidate therapeutic target for GC. Here, we analyzed the clinicopathological significance of DDX27 using immunohistochemistry and studied its functions using knockdown assays. We found that DDX27 was frequently upregulated in GC tissues (98 of 140 cases, 70%), and significantly associated with venous invasion and liver metastasis. Furthermore, multivariate analysis of GC patients showed that high expression of DDX27 was independently associated with poorer prognosis. In functional assays, knockdown of DDX27 reduced the ability of GC cells to form colonies both on conventional plates and soft agar, but had little effect on their invasiveness. We also found that knockdown of DDX27 reduced the viability of GC cells through inhibition of cell cycle progression independently of apoptosis. Interestingly, DDX27 depletion induced accumulation of TP53 in a TP53 wild-type cell line, AGS, but not in a TP53-deleted cell line, 44As3, although DDX27 knockdown commonly reduced the viability of both, indicating the TP53-dependent and independent cell cycle control of DDX27. Thus, our results suggest that expression of DDX27 contributes to colony formation by GC cells through cell cycle control and may be a potential therapeutic target for GC patients with chromosome gain at 20q13. 相似文献
22.
目的模拟比较牙槽突裂植骨前后上颌扩弓对上颌牙槽骨位移影响。方法在已建立的植骨前上颌骨有限元模型上,采用ANSYS软件模拟牙槽突裂植骨,形成植骨后上颌骨模型。在2组模型上分别施加相同上颌扩弓力,观察比较牙槽骨区域三维方向位移形变情况。结果三维方向位移量比较,植骨前扩弓组均显著大于植骨后扩弓组(P<0.05)。水平向位移:植骨前扩弓,由前向后牙槽骨区域位移量逐渐降低;植骨后扩弓,由前向后牙槽骨区域位移量逐渐升高;植骨前后扩弓健侧牙槽骨位移量均显著大于患侧(P<0.05)。垂直向位移:植骨前后扩弓,牙槽骨前内侧均向下移动,牙槽骨后外侧均向上移动。矢状向位移:植骨前扩弓,牙槽骨前内侧向前移动,后外侧向后移动,植骨后扩弓移动趋势相反。结论单侧完全性唇腭裂患者植骨前扩弓三维方向移动均较植骨后明显,植骨前扩弓建议扩弓器适当向后移动,植骨后扩弓建议扩弓器适当向前移动并配合前牵引治疗,同时治疗中需警惕不对称扩弓及前牙开的发生。 相似文献
23.
24.
V6O13 thin films were deposited on indium-doped tin oxide (ITO) conductive glass by a concise low-temperature liquid-phase deposition method and through heat treatment. The obtained films were directly used as electrodes without adding any other media. The results indicate that the film annealed at 400 °C exhibited an excellent cycling performance, which remained at 82.7% of capacity after 100 cycles. The film annealed at 400 °C with diffusion coefficients of 6.08 × 10−12 cm2·s−1 (Li+ insertion) and 5.46 × 10−12 cm2·s−1 (Li+ extraction) in the V6O13 film electrode. The high diffusion coefficients could be ascribed to the porous morphology composed of ultrathin nanosheets. Moreover, the film endured phase transitions during electrochemical cycling, the V6O13 partially transformed to Li0.6V1.67O3.67, Li3VO4, and VO2 with the insertion of Li+ into the lattice, and Li0.6V1.67O3.67, Li3VO4, and VO2 partially reversibly transformed backwards to V6O13 with the extraction of Li+ from the lattice. The phase transition can be attributed to the unique structure and morphology with enough active sites and ions diffusion channels during cycles. Such findings reveal a bright idea to prepare high-performance cathode materials for LIBs. 相似文献
25.
Among various processes for manufacturing complex-shaped metal parts, additive manufacturing is highlighted as a process capable of reducing the wastage of materials without requiring a post-process, such as machining and finishing. In particular, it is a suitable new manufacturing technology for producing AISI H13 tool steel for hot-worked molds with complex cooling channels. In this study, we manufactured AISI H13 tool steel using the laser power bed fusion (LPBF) process and investigated the effects of tempering temperature and holding time on its microstructure and mechanical properties. The mechanical properties of the sub-grain cell microstructure of the AISI H13 tool steel manufactured using the LPBF process were superior to that of the H13 tool steel manufactured using the conventional method. These sub-grain cells decomposed and disappeared during the austenitizing process; however, the mechanical properties could be restored at a tempering temperature of 500 °C or higher owing to the secondary hardening and distribution of carbides. Furthermore, the mechanical properties deteriorated because of the decomposition of the martensite phase and the accumulation and coarsening of carbides when over-tempering occurred at 500 °C for 5 h and 550 °C for 3 h. 相似文献
26.
Lu Qin Fei-Zhou Zhang Jian-Hai Lv Lan-Fang Tang 《Journal of clinical research in pediatric endocrinology》2022,14(3):339
Xq22.3-q23 microdeletion is a rare genomic disorder. The purpose of this study was to emphasize the correlation between clinical phenotype and genotype of proximal deletion on chromosome Xq22.3-q23. A 5 years old boy had a 671 KB microdeletion on Xq23 by chromosomal microarray analysis, including AMMECR1 and CHRDL1 genes. He presented with microsomia, midface hypoplasia, right kidney dysplasia and mildly motor retardation, which have not previously been reported in relation to Xq23 deletion. To the best of our knowledge, this is the first case with Xq23 microdeletion. A total of nine cases with microdeletion at Xq22.3-q23 affecting AMMECR1 and two cases with CHRDL1 mutation were reviewed. This review showed that Xq23 microdeletion with microsomia, midface hypoplasia, kidney dysplasia, and mild motor retardation was rare. The previous literature showed two novel point mutations in AMMECR1 and CHRDL1 with some phenotype difference from the presented case. Xq23 microdeletion should be considered for patients with microsomia, midface hypoplasia, kidney dysplasia and growth retardation. 相似文献
27.
目的探讨抑制miR-204表达对宫内发育迟缓(intrauterine growth restriction,IUGR)新生大鼠学习记忆能力的影响及机制。方法采用低蛋白饮食法建立IUGR大鼠模型,将3日龄IUGR幼鼠设为模型组、miRNA拮抗剂对照组(antagomir-NC组)和miR-204拮抗剂组(antagomir组),另取正常幼鼠设为对照组,每组10只。Morris水迷宫实验测定大鼠学习与记忆能力;qRT-PCR检测各组大鼠海马组织中miR-204和脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)mRNA表达水平;尼氏染色、Tunel法观察海马组织尼氏小体数量和细胞凋亡水平;Western blot检测海马组织中BDNF/TrkB信号通路相关蛋白表达水平。结果与对照组比较,模型组大鼠逃避潜伏期增加,跨台次数减少;海马组织中细胞凋亡率和miR-204表达水平升高,而尼氏小体数量、BDNF mRNA,以及BDNF、p-TrkB和p-CREB蛋白表达水平降低(P<0.001)。抑制miR-204表达后,IUGR大鼠海马组织中尼氏小体数量、BDNF mRNA,以及BDNF、p-TrkB和p-CREB 蛋白表达水平升高,细胞凋亡率和miR-204表达水平降低,逃避潜伏期减少,跨台次数增加(P<0.001)。结论抑制miR-204可改善IUGR新生大鼠学习及记忆功能,其作用机制可能与靶向激活BDNF/TrkB信号通路有关。 相似文献
28.
目的:探讨apelin-13对高尿酸诱导的3T3-L1脂肪细胞氧化应激的作用及其机制。方法:3T3-L1脂肪细胞予以10 mg/dL尿酸刺激,部分细胞予以1μmol/L apelin-13预处理,以100μmol/L H2O2刺激的细胞为阳性对照。48 h后,流式细胞术检测活性氧族(ROS)含量,生化试剂盒检测细胞及培养液上清抗氧化酶[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)]和促氧化酶NADPH氧化酶(NOX)的活性以及丙二醛(MDA)含量,real-time PCR法检测细胞局部肾素-血管紧张素系统(RAS)各组份血管紧张素原(AGT)、血管紧张素转化酶I(ACE1)、血管紧张素II 1型受体(AT1R)和AT2R及血管紧张素II 1型受体相关蛋(APJ)的mRNA表达水平,ELISA法检测细胞及培养液中血管紧张素II(AngⅡ)浓度。结果:10 mg/dL的尿酸明显降低3T3-L1脂肪细胞SOD、GSH-Px和CAT的活性,升高NOX的活性,增加MDA的含量,细胞内ROS的含量相应升高;apel... 相似文献
29.
NMR测定灵敏度较低,对于那些天然丰度低而磁矩又较小的核,这一问题更为突出。70年代末80年代初,出现了一系列基于极化转移技术的多脉冲序列方法如INEPT~*和DEPT~(**)等,用于测定~(18)CNMR谱,极大地提高了灵敏度,其增强因子与偶极—偶极弛豫是否 相似文献
30.
《Patient education and counseling》2021,104(11):2791-2802
ObjectivePatient activation has been identified as a crucial determinant of health, but little is known about its own determinants, particularly in low socioeconomic status populations. To address this research gap, we analyzed factors that might explain variation in patient activation in such a population.MethodsWe conducted a cross-sectional patient survey (n = 582) in a low socioeconomic status urban district in Germany in 2017. Using multivariate linear regressions, we examined the association between patient activation and a range of psychological, sociodemographic, and health-related factors. To assess the relative importance of these factors, we used dominance analysis.ResultsOur results suggest that age, employment status, linguistic acculturation, health status, and self-efficacy were significantly associated with patient activation. Dominance analysis indicated that self-efficacy was the most important factor explaining variation in patient activation.ConclusionsAge, employment status, linguistic acculturation, health status, and self-efficacy are important determinants of patient activation.Practice implicationsOur results can inform decision makers about approaches for more targeted and effective interventions to improve patient activation in low socioeconomic status populations. Much might be gained by investing in interventions that focus on age, employment status, linguistic acculturation, and health status. Interventions that improve self-efficacy may represent a particularly promising approach. 相似文献