双三体胚胎干细胞的增殖与分化特征分析

该文旨在研究双三体胚胎干细胞(embryonic stem cells,ESCs)在细胞增殖、分化以及畸胎瘤形成等方面的特征,揭示非整倍体与肿瘤发生之间的关系。首先建立了两株常染色体双三体的小鼠ESC株系,通过微阵列比较基因组杂交(array comparative genomic hybridization,array CGH)和荧光原位杂交(fluorescence in situ hybridization,FISH)实验对双三体ESC株系进行了染色体拷贝数分析和核型鉴定;通过绘制细胞生长曲线检测了双三体ESCs的增殖能力;通过流式细胞术检测了双三体ESCs的细胞周期和细胞凋亡情况;采用细胞克隆形成实验分析了双三体ESCs的克隆形成效率;通过实时荧光定量PCR和免疫荧光染色实验检测了双三体ESCs中多能干细胞标志物的表达;通过撤掉培养体系中的白血病抑制因子(leukemia inhibitory factor,LIF)诱导分化和进行拟胚体(embryoid body,EB)形成实验检测了双三体ESCs的分化能力;通过重度联合免疫缺陷(severe combined immunodeficiency,SCID)小鼠皮下接种细胞实验分析了双三体ESCs的畸胎瘤形成能力和体内分化能力。结果显示,这两株双三体细胞分别是3号与6号染色体双三体并伴有Y染色体丢失的ESCs(DTs-3+6),以及6号与8号染色体双三体的ESCs(DTs-6+8)。双三体ESCs表现出相对于野生型细胞较强的生长增殖能力和OCT4、SOX2、NANOG等多能干细胞标志物的高表达。当培养液中不添加LIF时,野生型细胞基本完全走向分化,而双三体细胞形成许多未分化或部分分化的克隆,碱性磷酸酶(alkaline phosphatase,AP)染色阳性。在EB分化早期,双三体细胞中Fgf5、T、Foxa2等三胚层标志物的表达水平较野生型细胞明显降低,分化滞后。当被接种到SCID小鼠皮下后,双三体ESCs形成畸胎瘤的能力较野生型细胞增强,畸胎瘤中包含大量未分化区域。因此,双三体ESCs的生长增殖能力增强,它通过限制细胞分化能力而促进畸胎瘤形成。双三体ESCs是研究非整倍体在肿瘤发生发展过程中作用的重要模型。     

过表达CREG抑制ox-LDL诱导的人血管平滑肌细胞增殖

目的：探讨E1A 激活基因阻遏子（Cellular repressor of E1A-stimulated genes，CREG）在氧化型低密度脂蛋白（Oxidized low density lipoprotein，ox-LDL）引起的人血管平滑肌细胞（Vascular smooth muscle cell，VSMC）增殖中的作用及可能机制。方法：用60 滋g/mL ox-LDL处理人胸主动脉VSMC，在不同时间点（0 h，12 h，24 h，48 h）计数细胞并绘制生长曲线；在48 h时间点进行BrdU 染色检测增殖细胞的比率；采用Western Blot 检测各时间点CREG 表达。通过向VSMC 中转染携带CREG基因的质粒载体，筛选 获得过表达CREG 的VSMC（VSMCCREG）。进一步用ox-LDL 处理VSMCCREG，采用前述方法绘制生长曲线、进行48 h时间点 BrdU染色并检测CREG 和磷酸化Erk1/2 的表达。结果：与未经处理的对照组VSMC 相比，ox-LDL处理的VMSC 细胞总数及 BrdU阳性细胞比率显著增加；并且，CREG 表达随处理时间延长逐渐降低。此外，与ox-LDL 处理的VSMC 组相比，ox-LDL 处理 的VSMCCREG 组细胞总数及BrdU 阳性细胞比率均显著下降；并且CREG 表达增加、磷酸化Erk1/2 水平下降。结论：过表达 CREG 可能通过降低Erk1/2 磷酸化抑制ox-LDL诱导的人VSMC 增殖。     

SM22α在细胞骨架组构及血管重塑中的作用

血管平滑肌细胞（VSMC）表型转化是动脉粥样硬化、高血压和血管成形术后再狭窄等血管重塑性疾病的共同病理生理过程。VSMC表型转化过程中平滑肌特异基因的表达变化和细胞骨架的组构是当前研究的热点问题之一。平滑肌22α（SM22α）是近年发现的一种VSMC分化标志物,其表达具有平滑肌组织特异性和细胞表型特异性,该蛋白作为一种肌动蛋白细胞骨架相关蛋白参与VSMC骨架组构和收缩调节。本文就SM22α的结构特征及其在VSMC骨架组构和血管重塑中的作用机制进行综述。     

余甘子提取物调控LINC01772/miR-153对肺癌细胞A549生物学行为的影响

摘要 目的：探讨余甘子提取物对肺癌细胞A549增殖、迁移和侵袭的影响及机制。方法：体外培养A549细胞,分为对照组、不同剂量（低、中、高剂量）余甘子提取物组、si-NC组、si-LINC01772组、高剂量余甘子提取物+pcDNA组和高剂量余甘子提取物+pcDNA-LINC01772组,细胞计数试剂盒（CCK-8）法和克隆形成实验检测细胞增殖,划痕实验检测细胞迁移,嵌入式细胞共培养法（Transwell）检测细胞侵袭,免疫印迹法（Western Blot）检测细胞中上皮型钙黏蛋白（E-cadherin）和神经型钙黏蛋白（N-cadherin）蛋白表达水平,实时荧光定量PCR（RT-qPCR）检测LINC01772和miR-153表达水平。双荧光素酶报告基因实验验证LINC01772和miR-153调控关系。结果：与对照组相比,不同剂量余甘子提取物组A549细胞中LINC01772表达降低,且光密度值（OD值）、克隆形成数、迁移以及侵袭细胞数减少（P<0.05）,而miR-153含量与E-cadherin蛋白表达升高（P<0.05）,且呈剂量依赖性（P<0.05）。LINC01772在A549细胞中负调控miR-153表达。与si-NC组相比,si-LINC01772组A549细胞增殖,侵袭及迁移能力受到抑制（P<0.05）。与高剂量余甘子提取物+pcDNA组相比,高剂量余甘子提取物+pcDNA-LINC01772组A549细胞增殖,侵袭及迁移能力增强（P<0.05）。结论：余甘子提取物可能通过调控LINC01772/miR-153轴抑制肺癌细胞A549增殖、迁移和侵袭,其可能通过下调LINC01772进而上调miR-153表达发挥作用,具有开发为治疗肺癌药物的潜在价值。     

全反式维甲酸抑制血管平滑肌增殖的作用机制

血管平滑肌细胞（vascular smooth muscle cells,VSMC）的增殖是动脉粥样硬化等血管增生性疾病的重要病理特征。因此,抑制VSMC增殖及促进其分化的药物均有望用于动脉粥样硬化的治疗。全反式维甲酸（ATRA）是具有广泛生物学效应的维生素A类物质。研究证实ATRA可与VSMC中存在的维甲酸类受体结合,调控VSMC从低分化的合成型转变为成熟的收缩袁型,进而防止其过度增殖。     

番茄红素对血管平滑肌细胞增殖与凋亡的影响

目的:VSMCs增殖是动脉粥样硬化的主要病理过程之一.本研究通过观察番茄红素对人血管平滑肌细胞(VSMC)增殖和凋亡的影响,并探讨与Toll样受体4(TLR-4)有关的信号通路相关分子机制,旨在为番茄红素治疗动脉粥样硬化提供理论基础.方法:番茄红素处理体外培养的VSMC,分别应用MTT及流式细胞术分析处理后的VSMC增殖及凋亡情况;采用荧光定量PCR和Western blot检测处理后VSMC的TLR-4及骨髓分化分子88 (MyD88)表达水平的变化;ELISA检测番茄红素对VSMC肿瘤坏死因子α(TNF-α)及白细胞介素6 (IL-6)分泌量的影响.结果:番茄红素处理后VSMC细胞增殖速度降低,凋亡增加;番茄红素处理后VSMC内TLR-4及MyD88的表达降低,TNF-α及IL-6分泌减少.结论:番茄红素可抑制VSMC生长增殖;促进凋亡,从而发挥治疗动脉粥样硬化的作用,其机制可能与TLR-4及MyD88表达降低、TNF-α及IL-6分泌减少有关.     

黄芪总黄酮对柯萨奇B3病毒感染乳鼠心肌细胞miRNA378和miRNA378*表达的影响

目的：研究柯萨奇B3病毒（CVB3）感染乳鼠心肌细胞miRNA378和miRNA378^*表达的作用。方法：原代培养乳鼠心肌细胞分3组（n=6）：对照组（正常细胞）、CVB感染组（正常细胞+CVB3）、黄芪总黄酮组（正常细胞+CVB3+黄芪总黄酮）。CVB感染组感染CVB3,黄芪总黄酮组感染CVB3同时给予黄芪总黄酮20 mg/L。采用免疫组化方法检测乳鼠心室肌细胞α-SMA蛋白,实时荧光定量PCR技术检测各组心肌细胞miRNA378及miRNA378^*表达。结果：①与对照组相比较,CVB感染组心肌细胞miRNA378及miRNA378^*表达明显减少（P<0.01）;②与CVB感染组比较,黄芪总黄酮心肌细胞miRNA378及miRNA378^*表达明显增加（P<0.01）。结论：黄芪总黄酮可以减少CVB3感染心肌细胞miRNA378及miRNA378^*表达。     

人胚胎干细胞的自主分化

人胚胎干细胞(human embryonic stem cells,h ESCs)具有自我更新的能力及多向分化的潜能。诱导其定向分化一直是近年来的研究热点,但关于其自主分化的研究却不多。本实验使用无血清培养液mTeSR誖1培养hESCs,碱性磷酸酶检测显示其维持了未分化的状态。改用自主分化培养液后,通过形态观察、实时定量PCR(quantitative real-time PCR,q PCR)、免疫荧光及流式细胞术等方法对自主分化的细胞进行鉴定,从而探讨hESCs自主分化的方向和规律。实验结果表明,形态上分化细胞表现出均一的纤维状;基因和蛋白水平上,中胚层的VIMENTIN和SNAIL2显著表达,而外胚层的NESTIN以及内胚层的SOX17则无表达;流式细胞术检测分化细胞的CD29及CD44,表达量分别为92.8%和30.0%。由此可得出结论:hESCs的自主分化倾向于中胚层方向。     

SM22α对血管平滑肌细胞骨架及收缩功能的影响

SM22α(smooth muscle 22 alpha,SM22α)是血管平滑肌细胞(vascular smooth muscle cells,VSMC)的标志蛋白,为了探讨该蛋白与VSMC表型和功能的关系,利用血清饥饿法诱导VSMC由合成型向收缩型转变,用RT—PCR对不同表型VSMC的SM22α表达活性进行检测,并通过转染反义SM22α表达载体,观察SM22α表达对VSMC细胞骨架和收缩功能的影响。结果显示,在VSMC由合成型逆转为收缩型的过程中,SM22α和平滑肌α-肌动蛋白(smooth muscle α—actin,SMα—actin)的表达分别被显诱导和轻度上调,与此同时,细胞骨架由稀疏的网格状变成均匀、致密的束状,VSMC重新获得收缩功能。用反义SM22α抑制该基因表达后,血清饥饿诱导的VSMC细胞骨架重构受阻,乙酰胆碱刺激引发的细胞收缩消失。结果提示,SM22α参与VSMC细胞骨架的构成及调节细胞的收缩功能,对维持VSMC处于收缩表型具有重要作用。     

Wnt3a诱导小鼠胚胎干细胞向心肌细胞分化的研究

目的：研究Wnt3a在诱导小鼠胚胎干细胞心肌细胞分化中的作用和原理。方法：设计不同浓度,不同成分的Wnt3a条件培养基对小鼠胚胎干细胞诱导分化,对分化细胞进行形态学鉴定,通过免疫细胞化学检测心肌肌钙蛋白-T（cTnT）的表达,通过RT．PCR检测肌球蛋白重链（ot．MHC）和肌球蛋白轻链（MLC．2v）的表达。结果：Wnt3a诱导小鼠胚胎干细胞分化为心肌样细胞,分化细胞具有自动收缩性,免疫细胞化学检测心肌肌钙蛋白．T（cTllT）表达阳性,RT．PCR检测肌球蛋白重链（d—MHC）和肌球蛋白轻链（MLC-2v）表达阳性。经典Wnt信号途径的抑制剂Frizzled一8／Fc,能够抑制Wnt3a的诱导分化作用。结论：Wnt3a通过经典Wnt信号途径诱导小鼠胚胎干细胞向心肌细胞分化。     

Comparing the Effect of Uniaxial Cyclic Mechanical Stimulation and Chemical Factors on Myogenin and Myh2 Expression in Mouse Embryonic and Bone Marrow Derived Mesenchymal Stem Cells

Background: Environmental factors affect stem cell differentiation. In addition to chemical factors, mechanical signals have been suggested to enhance myogenic differentiation of stem cells. Therefore, this study was undertaken to illustrate and compare the effect of chemical and mechanical stimuli on Myogenin (MyoG) and Myosin heavy chani 2 (Myh2) expression of mouse bone marrowderived mesenchymal stem cells (BMSCs) and embryonic stem cells (ESCs). Methods: After isolation and expansion of BMSCs and generation of embryoid bodies and spontaneous differentiation of ESCs, cells were examined in 4 groups: (1) control group: untreated cells; (2) chemical group: cells incubated in myogenic medium (5-azacythidine and horse serum for BMSCs, dimethyl sulfoxide (DMSO) and horse serum for ESCs) for 5 days; (3) mechanical group: cells exposed to uniaxial cyclic strain (8%, 1 Hz, 24 h) and (4) chemical + mechanical group: cells incubated in myogenic medium for 4 days and then exposed to uniaxial cyclic strain. Real-time PCR was used to examine the expression of MyoG and Myh2 as specific myogenic markers. Results: suggested that mechanical loading, as a single factor, could elevate MyoG and Myh2 expression. Combining chemical with mechanical factor increases expression and there was no significant difference in MyoG expression of ESCs- and MSCs-chemical + mechanical groups; however, Myh2 expression was significantly higher in ESCs-mechanical group than that in the same group of MSCs.     

Downregulated lncRNA RCPCD promotes differentiation of embryonic stem cells into cardiac pacemaker-like cells by suppressing HCN4 promoter methylation

Long non-coding RNA (lncRNA) is receiving increasing attention in embryonic stem cells (ESCs) research. However, the roles of lncRNA in the differentiation of ESCs into pacemaker-like cells are still unclear. Therefore, the present study aims to explore the roles and mechanisms of lncRNA in the differentiation of ESCs into pacemaker-like cells. ESCs were cultured and induced differentiation to pacemaker-like cells. RNA sequencing was used to identify the differential expression lncRNAs during the differentiation of ESCs into pacemaker-like cells. Cell morphology observation, flow cytometry, quantitative real-time polymerase chain reaction, western blot, and immunofluorescence were used to detect the differentiation of ESCs into pacemaker-like cells. LncRNA and genes overexpression or knockdown through transfected adenovirus in the differentiation process. The fluorescence in situ hybridization (FISH) detected the lncRNA location in the differentiated ESCs. Luciferase reporter gene assay, methylation-specific PCR, chromatin immunoprecipitation assay, and RNA immunoprecipitation assay were performed to reveal the mechanism of lncRNA-regulating HCN4 expression. Rescue experiments were used to confirm that lncRNA regulates the differentiation of ESCs into pacemaker-like cells through HCN4. We cultured the ESCs and induced the differentiation of ESCs into pacemaker-like cells successfully. The expression of lncRNA RCPCD was significantly decreased in the differentiation of ESCs into pacemaker-like cells. Overexpression of RCPCD inhibited the differentiation of ESCs into pacemaker-like cells. RCPCD inhibited the expression of HCN4 by increasing HCN4 methylation at the promoter region through DNMT1, DNMT2, and DNMT3. RCPCD inhibited the differentiation of ESCs into pacemaker-like cells by inhibiting the expression of HCN4. Our results confirm the roles and mechanism of lncRNA RCPCD in the differentiation of ESCs into pacemaker-like cells, which could pave the path for the development of a cell-based biological pacemaker.Subject terms: Arrhythmias, Stem-cell research     

调节TGF-β1/Smad信号通路对内质网应激状态下肝癌HepG2细胞凋亡的影响

目的: 探讨TGF-β1/Smad信号通路对内质网应激(ERS)状态下肝癌HepG2细胞凋亡的影响机制。方法: 首先建立内质网应激模型:以3 μmol/L的衣霉素(TM)处理人肝癌HepG2细胞株24 h,诱导细胞发生ERS。实验分为6组,每组3个复孔,实验重复3次,6组分别为:Untreated组(未处理组)、TM组(3 μmol/L TM处理组)、TM+NC组(3 μmol/L TM+si-TGF-β1阴性对照组)、TM+si-TGF-β1组(3 μmol/L TM+si-TGF-β1组)、TM+pEX-3组(3 μmol/L TM+质粒对照组)及TM+TGF-β1 pEX-3组(3 μmol/L TM+TGF-β1过表达质粒组),利用脂质体的方法将TGF-β1小干扰RNA(si-TGF-β1)及TGF-β1过表达质粒(TGF-β1 pEX-3)转染入HepG2细胞,转染24 h后,利用RT-qPCR和Western blot检测各组HepG2细胞TGF-β1/Smad信号通路相关因子TGF-β1、p-Smad2表达的情况;CCK-8和流式细胞术分别检测各组HepG2细胞增殖抑制率和凋亡率变化情况。结果: 与Untreated组相比,TM组细胞的TGF-β1及p-Smad2的表达明显降低(P＜0.05);与TM组相比,TM+si-TGF-β1组细胞的TGF-β1及p-Smad2的表达和细胞的增殖抑制率、凋亡率显著降低(P＜0.01),而TM+TGF-β1 pEX-3组细胞的TGF-β1及p-Smad2的表达和细胞增殖抑制率、凋亡率显著升高(P＜0.01)。结论: TGF-β1/Smad信号通路在肝癌HepG2细胞发生ERS后受到抑制,当该通路被激活后,ERS状态下肝癌HepG2细胞的凋亡率显著升高。     

Effects of rutin on osteoblast MC3T3-E1 differentiation,ALP activity and Runx2 protein expression

As a flavonoid, rutin has been found to have a wide range of biological functions, such as resisting inflammation and oxidation, and preventing cerebral hemorrhage and hypertension. It has been found to play an important role in osteoporosis and other orthopedic diseases in recent years. MC3T3-E1 cells were randomly divided into a control group, a rutin-1 group (0.01 mmol/L), a rutin-2 group (0.05 mmol/L) and a rutin-3 group (0.1 mmol/L). Osteogenic differentiation of cells was induced by osteogenic induction fluid. The control group was treated with the maximum dose of drug solvent. 2~3 days later, the solvent was replaced with fresh osteogenic induction fluid containing rutin. After a certain period of routine culture, the cells were collected for subsequent experiments. The expression of Runx2 gene in cells in all groups was detected by Real-time PCR; the expression of Runx2 protein was detected by Western blot and immunocytochemistry (IHC); the activity of ALP was detected by reagent kit method; osteogenic differentiation was analyzed by alizarin red staining. The results of Real-time PCR showed that, compared with the control group, the treatment of cells with rutin can significantly increase the expression of Runx2 gene (p<0.05); the higher the concentration, the higher the expression of Runx2 gene, and significant differences were found among groups in which different concentrations were used (p<0.05); the results of Western blot and IHC showed that the expression trend of Runx2 protein in each group was consistent with PCR results. In drug treatment groups, the activity of ALP was significantly higher than that in the control group (p<0.05); there were significant differences among groups in which different concentrations were used (p<0.05). The results of alizarin red staining showed that calcified nodules were formed in all groups and that the area of calcified nodules formed in groups treated with rutin was greater than that in the control group; the greater the concentration, the larger the area. Rutin can promote osteoblastic differentiation; and the greater the concentration, the more effective it is.Key words: xRutin, Runx2, ALP, osteogenic differentiation     

Lipopolysaccharide regulates toll-like receptor 4 expression in human aortic smooth muscle cells

Lipopolysaccharide (LPS) is a potent activator of cells of the immune and inflammatory systems, including macrophages, monocytes, and endothelial cells (EC). Toll-like receptor 4 (TLR4) has been identified as the primary receptor for LPS. Vascular smooth muscle cells (VSMCs) likely contribute significantly to the inflammation induced by low-level LPS in patients who are at risk for atherosclerosis. Previous study indicated that functional TLR4 was present in VSMCs. However, it remains unclear whether low levels of commercial LPS preparations can affect TLR4 expression in early stage. Here Real-time quantitative PCR analysis was used to detect TLR4 mRNA expression; Immunofluorescence, Western blot analysis and flow cytometry were used to examine TLR4 protein expression. It was shown that TLR4 was present in Human Aortic Smooth Muscle Cells (HASMCs). LPS can up-regulate TLR4 mRNA and protein expression in HASMCs in dose- and time-dependent manner. These data indicate that LPS regulate TLR4 expression in HASMCs.     

Ghrelin联合三氧化二砷对骨髓间充质干细胞增殖与成骨分化的影响

该文主要探究Ghrelin对三氧化二砷(As2O3)导致的骨髓间充质干细胞(BMSCs)增殖和成骨分化的影响。BMSCs设为对照组、As2O3组、Ghrelin组和联合(As2O3+Ghrelin)组。MTT法检测细胞增殖能力;成骨诱导的第7天和第14天,Real-time PCR及Western blot分别检测成骨相关因子OPN、ALP、RUNX2的mRNA及蛋白表达;第21天,茜素红染色分析钙盐沉积情况。结果显示,细胞增殖能力Ghrelin组>对照组>联合组>As2O3组。与对照组比,As2O3组各因子表达均显著下调(P<0.05),Ghrelin组第14天OPN蛋白表达无显著变化,其余因子均上调(P<0.05);联合组与As2O3组比,第14天OPN基因表达和第7天ALP蛋白表达无显著差异,其余均显著上调(P<0.05)。钙盐沉积:Ghrelin组>对照组>联合组>As2O3组。提示0.5μmol/L As2O3抑制BMSCs增殖和成骨分化,600 ng/mL Ghrelin增强细胞增殖和成骨分化;且Ghrelin能减弱As2O3导致的BMSCs增殖和成骨分化抑制作用。     

Inhibition of insulin-like growth factor-1 (IGF-1) expression by prolonged transforming growth factor-β1 (TGF-β1) administration suppresses osteoblast differentiation

TGF-β1 can regulate osteoblast differentiation not only positively but also negatively. However, the mechanisms of negative regulation are not well understood. We previously established the reproducible model for studying the suppression of osteoblast differentiation by repeated or high dose treatment with TGF-β1, although single low dose TGF-β1 strongly induced osteoblast differentiation. The mRNA expression and protein level of insulin-like growth factor-1 (IGF-1) were remarkably decreased by repeated TGF-β1 administration in human periodontal ligament cells, human mesenchymal stem cells, and murine preosteoblast MC3T3-E1 cells. Repeated TGF-β1 administration subsequently decreased alkaline phosphatase (ALP) activity and mRNA expression of osteoblast differentiation marker genes, such as RUNX2, ALP, and bone sialoprotein (BSP). Additionally, repeated administration significantly reduced the downstream signaling pathway of IGF-1, such as Akt phosphorylation in these cells. Surprisingly, exogenous and overexpressed IGF-1 recovered ALP activity and mRNA expression of osteoblast differentiation marker genes even with repeated TGF-β1 administration. These facts indicate that the key mechanism of inhibition of osteoblast differentiation induced by repeated TGF-β1 treatment is simply due to the down-regulation of IGF-1 expression. Inhibition of IGF-1 signaling using small interfering RNA (siRNA) against insulin receptor substrate-1 (IRS-1) suppressed mRNA expression of RUNX2, ALP, BSP, and IGF-1 even with single TGF-β1 administration. This study showed that persistence of TGF-β1 inhibited osteoblast differentiation via suppression of IGF-1 expression and subsequent down-regulation of the PI3K/Akt pathway. We think this fact could open the way to use IGF-1 as a treatment tool for bone regeneration in prolonged inflammatory disease.     

敲除Pofut1不影响胚胎干细胞向神经元分化

蛋白O-连接岩藻糖基转移酶1 (Pofut1)基因缺失可导致Notch分子无法与配体结合并启动信号传递. 为研究Pofut1基因对哺乳动物胚胎干细胞（ESC）向神经分化的影响,利用Pofut1基因敲除的胚胎干细胞与野生型胚胎干细胞,经体外培养诱导拟胚体（EB）分化为神经细胞,计数分化为神经细胞的比例,采用细胞免疫组化染色和real-time PCR等方法,分析神经细胞特异性标志分子的表达. 结果显示,Pofut1基因缺失后,对EBC生长没有明显影响,分化过程中形成的拟胚体数量明显增多,分化的神经样细胞以及神经标志物分子的表达也明显多于对照组;Notch信号缺失对小鼠胚胎干细胞生长无明显影响,但可以促进ES细胞向神经细胞分化.     

桦木酸对人胃癌MGC-803细胞增殖的影响

目的:探究不同浓度桦木酸对人胃癌MGC-803细胞增殖的影响.方法:将人胃癌MGC-803细胞分成4组,每组设置3个复孔,对照组细胞为加入浓度为0 μg/ml的桦木酸实验组细胞分别加入终浓度为10、20、30 μg/ml的桦木酸,各组细胞在含5％的CO2培养箱中孵育48 h后,使用吉姆萨染色法和台盼蓝拒染法检测桦木酸对...