FGF8辅助牙源性上皮诱导hDPSCs分化为成牙本质细胞及牙髓细胞

目的:研究成纤维细胞生长因子8(FGF8)对成人牙髓干细胞(hDPSCs)定向分化为成牙本质细胞及牙髓组织的影响。方法:首先分离、克隆培养hDPSCs,通过流式细胞术检测细胞表面标志物鉴定hDPSCs;矿化液中添加50μg/L的FGF8诱导hDPSCs分化,通过real-time PCR检测分化后的细胞中牙本质涎磷蛋白(DSPP)、碱性磷酸酶(ALP)、骨涎蛋白(BSP)和核心结合因子α1(Cbfa-1)在mRNA水平的表达;E11.5小鼠牙源性上皮联合FGF8与hDPSCs细胞团重组,再将组织块种植于裸鼠肾囊膜下培养,通过DNA原位杂交鉴定成牙本质细胞及牙髓细胞的来源。结果:成功分离培养hDPSCs,其表面标志物CD29和CD90呈阳性表达;经FGF8诱导的hDPSCs形成较明显的矿化结节,并且牙本质特异性蛋白DSPP、BSP及Cbfa-1表达量上调;E11.5小鼠牙源性上皮联合FGF8可以诱导hDPSCs分化为成牙本质细胞及牙髓细胞。结论:FGF8能够辅助牙源性上皮定向诱导hDPSCs分化为成牙本质细胞及牙髓细胞,并形成牙本质及牙髓腔结构。     

转化生长因子β3诱导人乳牙牙髓干细胞向成牙本质样细胞的分化

背景：转化生长因子β3与肝素联合作用后对人乳牙牙髓干细胞的增殖和矿化能力的作用目前仍有待研究。目的：探讨转化生长因子β3对人乳牙牙髓干细胞向成牙本质样细胞分化的作用。方法：采用酶消化法将人乳牙牙髓分离培养,获得人乳牙牙髓干细胞;对体外培养的第3代人乳牙牙髓干细胞单独加入25 μg/L重组转化生长因子β3、10 U/mL肝素,或者二者联合进行培养;通过Q-PCR和Western-blotting方法,分别检测乳牙牙髓干细胞中牙本质涎磷蛋白基因及牙本质涎蛋白表达的情况;通过碱性磷酸酶试剂盒检测乳牙牙髓干细胞碱性磷酸酶活性的改变。结果与结论：乳牙牙髓干细胞在诱导体系中生长状态良好。25 μg/L转化生长因子β3+10 U/mL肝素联合作用组的碱性磷酸酶活性明显增强,与转化生长因子β3单独作用组、肝素单独作用组以及对照组相比差异有显著性意义(P < 0.01);转化生长因子β3+肝素联合作用组的茜素红染色呈强阳性,Q-PCR和Western-blotting结果均显示,转化生长因子β3+肝素联合作用组的牙本质涎磷蛋白mRNA和蛋白表达均明显升高。结果可见在转化生长因子β3与肝素联合作用的诱导下,可促进乳牙牙髓干细胞分化为成牙本质样细胞。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

儿童乳牙牙髓干细胞顺硬度基质表面延展和向牙本质分化的潜能

文题释义： 组织相容性：是一组被称为人类白细胞抗原(HLA)的基因具有相同或足够相似的等位基因的特性。与整个器官、组织或干细胞移植有关的主题最相关。人类6号染色体6p21.3处每个HLA位点存在大量等位基因,这些基因是共显性表达的,意味着每个个体都表达每个遗传的等位基因,包括父系和母系,导致每个个体都有不同类型的MHC蛋白的混合物。一个人的HLA等位基因的相似或差异,以及MHC蛋白与另一个人的相似或不同,是使组织相容或不相容的原因。 牙髓干细胞：2000年GRONTHOS等发现一种与骨髓间充质干细胞有着相似的免疫表型及形成矿化结节能力的梭形成纤维状细胞。这类细胞可自我更新和多向分化,并有着较强的克隆能力,经过不同细胞因子的诱导,能够分化为脂肪、骨、软骨、肌肉、血管内皮、肝、神经等细胞系类型,在牙组织工程中具有重要研究价值。 背景：牙髓干细胞在适宜诱导条件下能够向牙本质分化,是牙齿组织工程的重要种子细胞。然而,以往所使用的诱导剂多为化学制剂,不利于体内应用。近来有报道称间充质干细胞能够顺材质硬度分化,这种由物理特性诱导的细胞分化研究报道较少。 目的：观察人源性乳牙牙髓干细胞在硬介质表面的延展特点及向牙本质分化潜能,为牙组织工程提供参考。 方法：原代分离培养和鉴定儿童自然脱落的乳牙牙髓干细胞;使用低熔点琼脂糖配制弹性模量为(9.12±0.94),(27.18±3.55),(59.37±4.05)和(86.45±5.33) kPa 4个梯度的固体凝胶基质,二维克隆形成实验和划痕实验检测第4代乳牙牙髓干细胞在上述硬基质表面的延展能力,Western blot方法检测牙本质基质蛋白1、牙本质磷蛋白、牙本质涎蛋白的表达。 结果与结论：当人乳牙牙髓干细胞接种于极低和低等硬度凝胶介质表面时,乳牙牙髓干细胞几乎均以边缘整齐的细胞克隆存在,很少见细胞平铺和延展现象;但是当将其接种于中等和高等硬度凝胶介质表面时,乳牙牙髓干细胞克隆边缘则表现出明显的平铺和延展,表现为细胞胞体变大,细胞边缘外伸明显。相似的现象也经细胞划痕实验所验证。人源性乳牙牙髓干细胞在中等和高等弹性模量介质表面培养时,表达较高水平的牙本质基质蛋白1、牙本质磷蛋白、牙本质涎蛋白。结果表明,人源性乳牙牙髓干细胞随着培养基质硬度的增加其延展性及成牙本质分化能力逐渐增强,为未来牙组织工程提供方法借鉴。 ORCID: 0000-0002-5640-4472(刘晓智) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

牙髓干细胞成牙及成骨向分化调控方法的研究进展

牙髓干细胞(DPSC)是一种位于牙髓腔内,具有较强的自我更新能力和多向分化潜能的间充质干细胞,在再生医学中有着十分良好的应用前景。本文介绍了化合物诱导分化、物理方法诱导分化和支架及表面形貌诱导分化等调控方法与途径,并分析提出了不同调控方法的优势与不足,为牙髓干细胞成牙本质及成骨向分化调控的相关研究提供参考。     

牙髓牙本质复合体中VIP阳性神经纤维的研究

目的:研究血管活性肠肽(VIP)在牙髓牙本质复合体中的表达,探讨其功能。方法:收集人前磨牙,石蜡包埋切片,作免疫组织化学和图象定量分析。结果:VIP阳性神经纤维自根尖孔呈束状进入牙髓,至颈部扇形分开,在冠髓大量分支,部分围绕在血管周围,部分终止于牙髓基质,部分参与形成成牙本质细胞层下Raschkow神经丛,然后发出分支伸入成牙本质细胞层和前期牙本质,但不进入成熟牙本质。VIP阳性神经纤维在冠髓的积分光密度为12.74±1.807,体密度为0.0192±0.0127,线密度为0.0046±0.0029,在前期牙本质的积分光密度为13.07±1.927,线段长度为(19.60±8.597)mm。结论:VIP阳性神经纤维存在于人牙髓牙本质复合体,部分纤维围绕血管,部分纤维止于牙髓基质和前期牙本质,这种分布提示该纤维除与血管运动有关外,可能还与感觉有关,在痛觉传导、血管调节等方面发挥重要作用。     

SonicFill超声树脂对大鼠成牙本质细胞和牙髓微血管的影响

BACKGROUND: The mechanical properties of SonicFill ultrasonic resin are better than those of the traditional light-cured composite resin, but its effect on odontoblasts and dental pulp vessels is unclear.     

人前磨牙牙髓牙本质复合体层粘连蛋白的免疫组织化学研究

目的　研究层粘连蛋白在牙髓牙本质复合体内的表达 ,探讨其分布与功能的关系。　方法　收集不同年龄新鲜健康人前磨牙 6 0颗 ,固定 ,脱钙 ,石蜡包埋 ,层粘连蛋白免疫组织化学染色。　结果　层粘连蛋白免疫反应性 ( IR)普遍存在于牙髓、前期牙本质和成熟牙本质小管与成牙本质细胞突起之间 ,以牙髓的神经与血管周围最为丰富 ,冠髓较根髓密集。　结论　层粘连蛋白 IR不仅见于牙髓与前期牙本质 ,而且也见于成熟牙本质 ,它对支持、固定牙髓牙本质复合体各结构的正常位置、形态可能发挥了重要作用     

新生兔骨髓基质细胞向成骨样细胞诱导分化

最新研究表明骨髓基质细胞(bone marrow stromal cells,BMSCs)不仅是具有多向分化能和旺盛增殖活力的细胞,还具有特殊的免疫学特性,表达对异体宿主低免疫原性和免疫抑制作用[1].本实验分离培养的新生兔骨髓基质细胞,经成骨诱导可以为成年兔骨修复提供充足的骨组织工程种子细胞.     

Human Immature Dental Pulp Stem Cells (hIDPSCs), Their Application to Cell Therapy and Bioengineering: An Analysis by Systematic Revision of the Last Decade of Literature

During recent years, attention has been given to the potential of therapeutic approaches using stem cells obtained from dental pulp tissue. The aim of this study, therefore, was to give an overview of the papers produced during the last 10 years that have described the use of stem cells obtained from human deciduous teeth in cell therapy or bioengineering. The PubMed database was investigated from January 2002 until July 2011 and the papers published during this period were analyzed according to criteria previously established, using the methodology of systematic review. The measurements were done using “stem cell” as the primary keyword, and “human deciduous teeth dental pulp cell” and “human exfoliated deciduous teeth” as the secondary keywords. Four hundred and seventy‐five papers were found. The first screening resulted in 276 papers, from which 84 papers were selected. However, only 11 of them attained the aim proposed in our approach. There were few scientific studies related to direct therapeutic application using stem cells of human deciduous teeth and none of them had been applied to humans. However, the results indicated important and promising applications of the pulp stem‐cells in cell therapy and bioengineering as demonstrated by studies in animal models of muscular dystrophy, Parkison's disease, and lupus erythematosus. Anat Rec, 296:1923–1928, 2013. © 2013 Wiley Periodicals, Inc.     

大鼠牙髓细胞的分离培养及超微结构观察

目的 探讨牙髓细胞的培养方法和生长状况,观察其形态结构特征,为进一步研究牙齿的发育提供实验基础.方法 采用胶原酶消化分离的方法分离大鼠的牙髓细胞并在DMEM培养液中培养,运用透射和扫描电镜技术观察细胞的形态结构特征.结果 培养的牙髓细胞呈梭形,细胞生长状况良好,细胞器发育正常,并且有细胞增殖和分裂能力.结论 利用酶消化分离的方法分离培养的牙髓细胞,能够保持其生活状态及增殖分裂能力.     

细胞周期失调与大肠癌

细胞周期需要一系列因子组成的复杂网络系统和信号传导途径的准确调节,细胞周期失调与肿瘤发生密切相关,本文对细胞周期调节网络系统的组成及细胞周期失调与大肠癌的关系作一综述。     

JNK MAPK is involved in BMP-2-induced odontoblastic differentiation of human dental pulp cells

Bone morphogenetic protein-2 (BMP-2) is a multi-functional growth factor belonging to the transforming growth factor β superfamily that has a broad range of activities that affect many different cell types. BMP-2 induces odontoblastic differentiation of human dental pulp cells (DPCs), but the underlying mechanism remains unclear. In this study, we investigated the potential role of the JNK mitogen-activated protein kinases (MAPK) pathway in BMP-2-induced odontoblastic differentiation of DPCs. The levels of phosphorylated and unphosphorylated JNK MAPK were quantified by Western blot analysis following treatment with BMP-2 and the JNK inhibitor SP600125. The role of JNK MAPK in the BMP-2-induced odontoblastic differentiation of DPCs was determined by measuring alkaline phosphatase (ALP) activity and by examining the expression of odontoblastic markers using quantitative real-time polymerase chain reaction analysis. The effect of JNK MAPK silencing on odontoblastic differentiation was also investigated. BMP-2 upregulated the phosphorylation of JNK in DPCs in a dose- and time-dependent manner. Early markers of odontoblastic differentiation, including ALP activity, osteopontin and dentin matrix protein-1, were not inhibited by the JNK inhibitor. However, the JNK inhibitor, SP600125, significantly inhibited late-stage differentiation of odontoblasts, including the gene expression of osteocalcin, dentin sialophosphoprotein and bone sialoprotein, and also reduced the formation of mineralized nodules in BMP-2-treated DPCs. Consistent with this observation, silencing of JNK MAPK also decreased late-stage odontoblastic differentiation. Taken together, these findings suggest that JNK activity is required for late-stage odontoblastic differentiation induced by BMP-2.     

血红素加氧酶-1对肝癌细胞细胞周期调控因子的影响

目的 观察血红素加氧酶-1(heme oxygenase 1,HO-1)对人肝癌细胞HepG2细胞周期调控因子的影响.方法 构建含有野生型和突变型HO-1基因的重组载体pcDNA3.1(+)-wtHO-1和pcDNA3.1(+)-mHO-1G143H.利用脂质体介导的方法将构建好的重组载体转染肝癌细胞系HepG2,以空载体转染作为对照组.通过G418筛选建立稳定表达野生型和突变型HO-1的HepG2肝癌细胞系.经半定量RT-PCR、Western印迹检测转染细胞系中HO-1 mRNA和蛋白的表达水平.在HO-1表达改变的稳转细胞系中,利用Western 印迹检测转染细胞系中P21、P27蛋白表达水平.结果 成功实现了野生型和突变型HO-1在HepG2细胞中的过表达;野生型和突变型HO-1过表达均能诱导抑癌基因p21和p27的表达.结论 HO-1过表达诱导抑癌基因p21和p27的表达与血红素分解产物无关.HO-1可能通过其它机制调节p21和p27的表达.     

细胞周期调控与肿瘤

Cyclin、CDK、CKI是细胞周期调控的内源性分子,三者在细胞周期中相互协调并与细胞信号转导通路之间形成复杂的调控网络,与细胞增殖、细胞分化及细胞凋亡相关联。现发现肿瘤中存在相应基因的突变和表达失调,这些改变直接、间接导致细胞周期紊乱,与肿瘤发生密切相关,是分子遗传学和肿瘤生物学研究的热点。     

应用流式细胞术分析不同年龄大鼠脑组织细胞周期增殖特性

应用流式细胞术对不同年龄的大鼠的大脑、小脑和脑干组织的细胞周期进行分析。结果显示在相同年龄组不同部位的脑组织细胞增殖程度不均一,大脑细胞增殖明显高于小脑和脑干。同一部位的脑组织各年龄组之间细胞增殖情况亦存在差异。新生和幼年大鼠(出生后1天和21天)其脑细胞增殖较成年大鼠(6个月和1年)旺盛。实验还表明,特殊萤光素染色脑细胞DNA,然后用流式细胞仪测定DNA量,是一种简单、快速分析脑细胞增殖活性的可行技术。     

细胞增殖过程中整装培养细胞内质网膜系统的组建特点

利用高锰酸钾技术，通过透射电镜观察了经同步化处理的整装培养的正常细胞在细胞周期各时相中内质网膜系统的结构变化，发现细胞的内质网膜系统在细胞的生长发育过程中由直径较粗、稀疏而分散的网状结构，逐渐组建成直径较细、致密分布的连续网状结构     

Microenvironmental Control of the Breast Cancer Cell Cycle

The mammary gland is one of the best‐studied examples of an organ whose structure and function are influenced by reciprocal signaling and communication between cells and their microenvironment. The mammary epithelial cell (MEC) microenvironment includes stromal cells and extracellular matrix (ECM). Abundant evidence shows that the ECM and growth factors co‐operate to regulate cell cycle progression, and that the ECM is altered in breast tumors. In particular, mammographically dense breast tissue is a significant risk factor for developing breast carcinomas. Dense breast tissue is associated with increased stromal collagen and epithelial cell content. In this article, we overview recent studies addressing the effects of ECM composition on the breast cancer cell cycle. Although the normal breast ECM keeps the MEC cycle in check, the ECM remodeling associated with breast cancer positively regulates the MEC cycle. ECM effects on the downstream biochemical and mechanosignaling pathways in both normal and tumorigenic MECs will be reviewed. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

Changes in Mood and Autonomic Functioning During the Menstrual Cycle

The autonomic nervous system activity and mood ratings of 12 women were studied 6 days a week for a complete menstrual cycle. The daily procedure consisted of a resting period, a series of 5 mild tones, time estimation (TE), and reaction time (RT) trials, and a final resting period. Significant increase in heart rate (HR), respiration rate, and body temperature, and a significant decrease in resting skin conductance (SC) were found during the luteal phase. During the ovulatory phase there were significant increases in autonomic responsivity, as shown by greater amplitude of SC response in the TE and RT situations as well as in faster SC drop-rate and greater HR variability. All of these autonomic variability measures coincided with a significant peak in feelings of elation and vigor. Significant age effects were that older women had higher basal body temperatures, less marked HR variability, and tended to have lower levels of SC, particularly in the luteal phase of the cycle. The results are discussed in terms of the psychophysiological effects of estrogen and progesterone.