胚胎干细胞体外诱导分化的研究进展

胚胎干细胞(embryonicstemcell,ES细胞)是由早期胚胎内细胞团(ICM )或原始生殖(PGC)细胞经体外分离、抑制分化培养获得的多潜能细胞。ES细胞具有发育分化的多潜能性和无限的自我更新能力,能在体外长期培养并具有向机体各种组织细胞分化的潜能[1] 。由于ES细胞的全能性,在体外可以分化出包括3个胚层在内的所有细胞,如神经细胞、造血细胞、心肌细胞、骨骼肌细胞、脂肪细胞和原始内胚层细胞等,其某些分化机理与胚胎细胞在体内的分化是一致的。因此,ES细胞可用于胚胎发育和细胞分化调控的研究,作为修复器官和器官移植的种子细胞,还可用于…     

兔脂肪间质干细胞的分离培养与鉴定

取兔腹股沟皮下脂肪组织,用Ⅰ型胶原酶消化,分离培养脂肪间质干细胞(MSCs),并用免疫组化和体外诱导分化方法对其表面分子标志和多向分化潜能进行鉴定。结果显示,兔脂肪组织中能够分离培养出脂肪MSCs,该类细胞表达CD29、CD44和CD105,不表达CD34、CD45及HLA-DR表面分子标志,并具有可分化为脂肪细胞、神经细胞和成骨细胞的多向分化潜能,证实兔脂肪组织中存在具有多向分化潜能的MSCs。     

猪胚胎多能性干细胞的分离培养

收集妊娠 2 6 .0～ 2 9.0d的猪胚胎 ,分离培养原始生殖细胞 (PGCs) ,在STO细胞饲养层上生长 ,形成了多能性干细胞 (EG)。发现其具有干细胞的显著特性 ,并能在体外定向分化为神经细胞、上皮细胞和胚泡细胞。试验使用A、B、C 3种不同的培养基培养PGCs ,结果在形成EG细胞集落的数量和EG细胞分化上有着明显的差距 ,说明血清的质量和浓度以及细胞因子对干细胞的生成和增殖有着重要的影响     

酒精阳性乳牛血清中胰岛素含量的变化及其代谢关系的探讨

酒精阳性乳牛血清中胰岛素含量的变化及其代谢关系的探讨阎凤周，朱永宁，李莫南，刘景华，阮薇，王守云（吉林农业大学长春１３０１１８）胰岛素系胰腺β－细胞合成分泌的一种蛋白类，激素，它对机体内物质代谢调节具有重要作用，酒精阳性乳牛体内胰岛素的消涨如何目前尚...     

葛根素通过激活p38 MAPK信号通路促进MC3T3-E1细胞增殖的研究

为研究葛根素(PUE)对小鼠胚胎成骨细胞前体细胞(MC3T3-E1)的作用及其所关联的信号通路。通过培养MC3T3-E1细胞,运用CCK-8法对比加入不同浓度葛根素后细胞的增殖能力;通过CCK-8法检测最适浓度葛根素在不同时间对细胞增殖的影响;通过pNPP法测定碱性磷酸酶(ALP)的活性以检测不同浓度葛根素对细胞分化的影响;通过向p38丝裂原活化蛋白激酶(p38 mitogen activated proteinkinase,p38 MAPK)信号通路中加入p38抑制剂SB203580分析细胞分化水平;通过蛋白质免疫印迹技术检测p38磷酸化蛋白(P-p38)表达水平;通过ELISA检测Ⅰ型胶原分泌水平。结果显示,不同浓度葛根素作用于MC3T3-E1细胞,可以不同程度促进细胞的增殖和分化,其中浓度为1×10~(-6)mol/L葛根素组的促进作用显著高于其他组。最适浓度葛根素在不同时间对细胞增殖作用有明显差异,其中48 h对细胞增殖作用最为显著。葛根素可以激活ALP,促进Ⅰ型胶原分泌,诱导细胞的分化。使用抑制剂SB203580阻断p38 MAPK信号通路后,相比于对照组,细胞增殖、ALP活力以及P-p38蛋白的表达水平明显降低。结果表明,葛根素可以通过激活p38 MAPK信号通路促进MC3T3-E1细胞增殖和分化。     

周围神经浸出液对犬脂肪干细胞向神经膜细胞分化的影响

本研究旨在研究周围神经浸出液对犬脂肪源性干细胞(adipose derived stem cells,ADSCs)向神经膜细胞(Schwann cell,SCs)分化的影响。采用Ⅰ型胶原酶消化法体外原代培养犬ADSCs,并应用流式细胞术进行表型分析,同时观察所培养细胞的成脂成骨分化能力。分离犬坐骨神经,无菌剪碎、浸出和过滤制备犬周围神经浸出液。将周围神经浸出液作为诱导剂,作用于犬ADSCs,7d后分别通过倒置显微镜观察细胞形态的变化;免疫荧光试验和Western-blot观察SCs标志蛋白GFAP和S-100的表达情况。结果显示,周围神经浸出液作用于犬ADSCs 7d后,大多数细胞形态由原来的三角形或梭形变为两端伸出2个细长突起的长梭形,非常像成熟SCs的形态;免疫荧光和Western-blot试验显示,周围神经浸出液诱导ADSCs后,细胞出现GFAP和S-100阳性表达。以上结果提示,周围神经浸出液能有效诱导犬ADSCs向SCs分化。     

犬Mnx1基因过表达载体的构建及其对脂肪间充质干细胞向胰岛β细胞分化的影响

本研究旨在构建犬Mnx1基因腺病毒过表达载体,并探究Mnx1基因过表达对犬脂肪间充质干细胞向胰岛β细胞方向分化的影响。本试验构建了腺病毒重组表达载体pAD-Mnx1,经293A细胞包装扩增后产生具有感染性的重组腺病毒,将其按感染复数(MOI)100感染犬ADSCs后,分别在第3、6、9、12和15天观察绿色荧光蛋白的表达情况、细胞形态变化和胰岛β细胞发育相关基因的表达情况。结果显示,ADSCs在感染后24 h出现绿色荧光,形态无显著变化;Mnx1基因表达可激发胰十二指肠同源盒1(Pdx1)基因、神经元素3(Ngn3)基因、肌腱膜纤维肉瘤癌基因同源物A(Mafa)基因、NK2同源盒2(Nkx2.2)基因、NK6同源盒1(Nkx6.1)基因、神经分化因子1(Neurod1)基因、成对合基因4(Pax4)和GATA结合蛋白4(Gata4)基因等内源性基因的表达。结果证实,腺病毒介导的过表达载体pAD-Mnx1可在犬ADSCs超表达Mnx1基因,从而诱导犬ADSCs向胰岛前体细胞分化,具有进一步诱导犬ADSCs形成胰岛β细胞的可能。     

大鼠神经干细胞的分离培养和分化

分离大鼠大脑皮质及皮质下组织 ,经消化及机械吹打后 ,用悬浮培养法、有限稀释法获得来源于同一细胞的亚细胞系克隆 ;用免疫细胞化学法鉴定神经干细胞 (NSCs)。结果 ,从大鼠大脑皮质及皮质下分离的组织 ,经原代和传代培养均可形成细胞克隆 ,并具有增殖能力 ;原代和传代细胞抗原与抗巢蛋白 (nestin)单克隆抗体反应呈阳性 ;单细胞克隆能分化成神经元、星形胶质细胞和少突胶质细胞。结果表明 ,用此方法分离的细胞具有自我更新和分化潜能 ,有很强的增殖能力 ,是属于中枢神经系统的干细胞。     

利用CRISPR-dCas9系统促进脂肪干细胞的成骨诱导分化

为了建立一种快速促进脂肪间充质干细胞成骨诱导分化的方法,本研究利用CRISPR-dCas9系统快速激活成骨前体基因的表达,通过对细胞内前体基因转录的检测和诱导分化后茜素红染色来确定成骨诱导分化的效率。结果可见,通过CRISPR-dCas9系统可以快速地启动RUNX2和OSX基因的转录;经成骨诱导分化后茜素红染色显示,基因编辑过的细胞成骨诱导更快。本研究结果表明,通过CRISPR-On系统可以有效地促进成骨前体细胞相关基因RUNX2和OSX的表达,从而使得骨前体细胞相关基因可以被快速地内源性激活,使得脂肪间充质干细胞快速进入成骨诱导分化状态,促进成骨分化的潜能。     

人胚胎原始生殖细胞的原代培养

从 5～ 9周人胚胎生殖嵴中消化分离原生殖细胞 (PGC) ,将其置于经过丝裂霉素C处理过的单层小鼠胚胎成纤维细胞 (PMEF)饲养层上培养。结果 ,经过培养形成的克隆以及克隆的生长方式基本符合小鼠胚胎干细胞 (ES)的特性 ,表现为细胞核大 ,细胞排列紧密 ,界限不清 ,集落边缘可见分化的成纤维细胞等 ;将其接种于裸鼠皮下 ,经过 2 9d生长 ,得到具有 3个胚层组织结构的畸胎瘤     

China＇s Rise vs. International Order Evolution

A heated debate over the rise of China has been going on unabated in the international community for nearly two decades. However, with the elapse of time, the initial divergence of views in the mainstream opinion has gradually diminished and the gap in China policy among nations has likewise narrowed down. Instead, reason and a realistic approach have eventually taken center stare.     

The U. S. Policy toward DPRK: Opportunities and Constraints

布什政府上台以来,始终未能阻止朝鲜拥核步伐.朝核试后,美对朝政策有了新的调整,六方会谈得以复会.但美朝双方受各自国家利益和政策目标的限制,在朝鲜半岛无核化问题上的尖锐分歧难以解决,朝核危机仍存在再度升级的可能.     

Marxist Philosophy vs. International Relations Research in China

This article argues for the confirmation of Marxist philosophy as the ideology that guides international relations （IR） studies in China. Justification comes through the following points. According to Marxism, correct theoretical guidance serves as the prerequisite for correct practice. Marxist philosophy embodies, by nature, righteousness, in opposition to political hegemony. Accordingly, practice under its guidance represents fruitful revolutionary realism. Finally, advanced studies of international relations in this country cannot be separated from philosophical thinking. Using these arguments as background, this article specifically advocates materialism, patriotism, and service to the people as the corner-stone of China＇s IR theory building.     

Excavating Concealed Tradeoffs: How Russians Watch the News

Citizens in democracies are expected to make better decisions if they understand policy tradeoffs. However, politicians rarely have incentives to communicate them; citizens are uncomfortable choosing among valued outcomes; and devising a common metric is difficult. It is not surprising that in the United States the environment provides relatively little cuing or priming of tradeoffs in television news. Russian citizens, on the other hand, face a media environment in which tradeoff cuing is intentionally suppressed by owners' agendas, yet viewers detect concealed tradeoffs even in the absence of tradeoff priming and viewpoint diversity. Analysis of discourse among ordinary Russians in 16 focus groups convened in four cities, differentiated by political reform and media market environments, showed that when watching news in which tradeoffs are thoroughly concealed, viewers challenge stories by offering a broad spectrum of uncued tradeoffs. Tradeoffs come from diverse policy domains and represent a range of cognitive strategies, some of which are considerably more abstract than others and link elements of their observations and assumptions (together with what they can extract from the stories) into complex reasoning outcomes.     

The U.S. Global Strategy as Seen from the Debate in the Primary Election

There may be more than one year to go before the 2008 U.S. presidential election, but the primary election of the two parties has already begun ahead of time. Both the Democratic and Republican candidates for the     

Young American China Watchers＇ Views on China

In this paper, the author has made a thorough study over the new generation of American China Watchers. Most of the pages are devoted to a detailed comparison between the old generation and the young generation of American China Watchers regarding to their background, education, and views over China. At the end of the paper, the author also gives some policy suggestions for both the Chinese and U.S. government based on the findings in this study.     

Constitution of the Chinese Associa tion for Interna tiona l Understa nding(Approved by the Plenary Session of the Eleventh Executive Council on April 2, 2014)

正Chapter I General Rules Article 1 The Chinese Association for International Understanding is a national non-governmental organization(NGO)in the People’s Republic of China.Article 2 The official name of the Association is"Zhong Guo Guo Ji Jiao Liu Xie Hui"in Chinese,or"Jiao Liu Xie Hui"for short.Its English translation is"Chinese Association for International Understanding",and abbreviated as"CAFIU".     

Guide to Authors

正Published by China Institute of International Studies,China International Studies is China’s first English-language journal on diplomacy and international politics for formal circulation.The magazine mainly publishes the latest research achievements of Chinese scholars and specialists on China’s diplomacy,international politics and international relations under such columns as China’s Diplomacy,International Relations,International Politics,International Security,Regional Issues and World Economy.     

My Journey to Artistic Peak

正I was born in a doctor’s family in a village in Heze,Shandong Province.Since the ancient times,Heze has been home to many painters and literature masters due to the influence of Confucianism.My grandfather and greatgrandfather were both good at calligraphy,not least to mention their medical skills.Even by now,senior people in our village still praise them for it.Both of them had deceased before I was born.     

Sidelights on Australian and New Zealand's Rotary Club Delegation's Visit to China

正At the invitation of the Chinese Association for International Understanding(CAFIU),a 6-member Australian and New Zealand’s Rotary Club delegation visited China from September 23 to September 27.As a staff member of CAFIU,I had the honor to take part in the reception of the delegation throughout this trip.