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1.
目的体外分离胰腺干细胞,选择最佳培养条件探索胰腺干细胞在体外环境下向β细胞的分化情况.方法取SD大鼠胰腺组织,胶原酶消化,密度梯度离心获得纯化的胰腺导管上皮细胞.采用分步诱导法诱导胰腺导管上皮细胞向胰岛β细胞分化;用胰岛素释放实验检测胰岛功能,免疫荧光法检测nestin,PDX-1,CK-19,CK-20胰岛素及胰高血糖素等的表达.结果胰腺消化培养6~12h,可看到胰腺导管上皮细胞贴壁生长,通过4步诱导培养,nestin阳性细胞快速生长,并可分泌胰岛素.结论体外分离的成人胰岛前体细胞,在诱导因子的作用下,胰腺干细胞可定向分化为β细胞,有望应用于糖尿病的治疗.  相似文献   

2.
To examine the effects of co-culture with bone marrow mesenchymal stem cells on expansion of hematopoietic stem/progenitor cells and the capacities of rapid neutrophil engraftment and hematopoietic reconstitution of the expanded cells, we expanded mononuclear cells (MNCs) and CD34+/c-kit+ cells from mouse bone marrow and transplanted the expanded cells into the irradiated mice. MNCs were isolated from mouse bone marrow and CD34+/c-kit+ cells were selected from MNCs by using MoFlo Cell Sorter. MNCs and CD34+/c-kit+ cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (MSCs) under a two-step expansion. The expanded cells were then transplanted into sublethally irradiated BDF1 mice. Results showed that the co-culture with MSCs resulted in expansions of median total nucleated cells, CD34+ cells, GM-CFC and HPP-CFC respectively by 10.8-, 4.8-, 65.9- and 38.8-fold for the mononuclear cell culture, and respectively by 76.1-, 2.9-, 71.7- and 51.8-fold for the CD34+/c-kit+ cell culture. The expanded cells could rapidly engraft in the sublethally irradiated mice and reconstitute their hematopoiesis. Co-cultures with MSCs in conjunction with two-step expansion increased expansions of total nucleated cells, GM-CFC and HPP-CFC, which led us to conclude MSCs may create favorable environment for expansions of hematopoietic stem/progenitor cells. The availability of increased numbers of expanded cells by the co-culture with MSCs may result in more rapid engraftment of neutrophils following infusion to transplant recipients. Project supported by NIH-Blood, Heart & Lung (National Institute of Health, USA, IR 01 4L70593-01) and Zhejiang Provincial Science Foundation (No. 011103397), China  相似文献   

3.
选用192只28±2d实验用清洁级SD大鼠,分为6组,每组32只,雌雄各半,分别饮用添加硼0、40、80、160、320和640mg/L的蒸馏水,试验期60d,分别于试验第30天(65日龄)和60天(95日龄)每组随机取鼠16只,雌雄各8只,10%水合氯醛腹腔麻醉,立即解剖取胰腺,称重,制作石蜡切片,HE染色,光镜观察并显微摄影。结果表明,与对照组比较,65d试验Ⅰ~Ⅳ雄鼠胰腺重量与器官指数降低,雌鼠胰腺重量与器官指数升高,95d试验Ⅰ~Ⅳ雄鼠和试验Ⅰ、Ⅱ组雌鼠胰腺重量升高,但均无统计学意义(P>0.05)。试验Ⅴ组大鼠的胰腺重量多显著或极显著低于对照组(P<0.05或P<0.01)。95d试验Ⅰ、Ⅱ组大鼠的胰腺的腺泡和胰岛结构较对照组有较明显地改善;试验Ⅲ~Ⅳ组胰腺的组织结构则呈现不同程度病理组织学变化;试验Ⅴ组胰腺腺泡细胞肿胀、顶部胞质酶原颗粒明显减少,胰岛体积变小,胰岛周边细胞萎缩,中央细胞肿胀。试验结果表明,饮水添加40、80mg/L硼对大鼠胰腺发育及组织结构有较明显地促进和改善作用;添加160~640mg/L硼对大鼠胰腺的发育及组织结构与功能则有较明显的不良影响甚至毒性作用;结果提示,微量元素硼对大鼠的胰腺发育及组织结构与功能的影响可能存在性别和日龄差异。  相似文献   

4.
本文用免疫组化的PAP法,观察了硫脲致甲低时,小鼠胰岛生长抑素(SS)免疫反应阳性细胞(D细胞)的变化。结果表明:硫脲致甲低时,小鼠胰岛中D细胞的数目显著地高于正常组。说明实验性甲低时,D细胞的功能是增强的。  相似文献   

5.
成体干细胞及其在医学上的应用   总被引:1,自引:0,他引:1  
干细胞分为胚胎干细胞和成体干细胞、综述了成体干细胞的生物学特性,目前研究的几种类型的成体干细胞,以及成体干细胞在医学上的应用.  相似文献   

6.
大鼠胰腺超微结构年龄变化与胰段移植的关系   总被引:3,自引:0,他引:3  
通过观察大鼠胰腺超微结构的不同年龄变化,发现胰腺外分泌部的腺细胞和内分泌部的B细胞结构变化与年龄增长相关,胰岛的分布以幼年鼠胰尾为最多。这说明胰腺移植的供体以幼年胰尾为佳,青年次之,老年不宜。  相似文献   

7.
通过浸渍干燥法制备了可集成至纺织品中的基于Ti3C2Tx的可穿戴温度传感器。所制备的柔性温度传感材料显示出负的电阻温度系数,其值为-0.36%℃-1,能满足可穿戴温度传感器的要求。展示了柔性温度传感器对温水与冷水的感知能力,验证其在实际场景中的应用潜力。  相似文献   

8.
Objective: To evaluate the transduction efficiency of a recombinant adenovirus carrying the gene for green fluorescent protein (Ad-GFP) into the primary cultures of fetal neural stem cells (NSCs) by the expression of GFP. Methods: The Ad-GFP was constructed by homologous recombination in bacteria with the AdEasy system; NSCs were isolated from rat fetal hippocampus and cultured as neurosphere suspensions. After infection with the recombinant Ad-GFP, NSCs were examined with a fluorescent microscopy and a flow cytometry for their expression of GFP. Results: After the viral infection, flow cytometry analysis revealed that the percentage of GFP-positive cells was as high as 97.05%. The infected NSCs sustained the GFP expression for above 4 weeks. After differentiated into astrocytes or neurons, they continued to express GFP efficiently. Conclusion: We have successfully constructed a viral vector Ad-GFP that can efficiently infect the primary NSCs. The reporter gene was showed fully and sustained expression in the infected cells as well as their differentiated progenies.  相似文献   

9.
绞股蓝皂甙和大豆皂甙对神经干细胞分化的影响   总被引:1,自引:0,他引:1  
Neural stem cell has a potential to differentiate into neurons, astrocytes and oligodendrocytes. It provides an in vitro model to screen herbal medicines on the cellular differentiation and development level. In this work, active component from gypenosides and soyasaponins was prepared to investigate their effects on the differentiation of neural stem cells.. Both gypenosides and soyasaponins promote the differentiation of neural stem cells. This method provides speed and practicality for screening effective herbal medicine. It is well suited for studying the mechanism of cell differentiation and development.  相似文献   

10.
比较了304L不锈钢粉末在不同压力下温压成形与冷压成形的生坯密度和生坯强度,并研究了烧结温度对304L粉末烧结性能的影响。试验结果表明,304L不锈钢粉末的温压生坯密度和生坯强度都高于冷压生坯密度和强度。在800 MPa的压制压力下,304L的温压生坯密度为7.07 g.cm-3,比冷压提高了0.24 g.cm-3,生坯强度为35.6 MPa,比冷压提高了22.8%。在1 300℃温度下真空烧结后,304L不锈钢粉末压坯的密度为7.50 g.cm-3,抗拉强度为471 MPa,延伸率为47.7%,硬度为65 HRB。  相似文献   

11.
Stem cells can be obtained from women’s menstrual blood derived from the endometrium. The cells display stem cell markers such as Oct-4, SSEA-4, Nanog, and c-kit (CD117), and have the potent ability to differentiate into various cell types, including the heart, nerve, bone, cartilage, and fat. There has been no evidence of teratoma, ectopic formation, or any immune response after transplantation into an animal model. These cells quickly regenerate after menstruation and secrete many growth factors to display recurrent angiogenesis. The plasticity and safety of the acquired cells have been demonstrated in many studies. Menstrual blood-derived stem cells (MenSCs) provide an alternative source of adult stem cells for research and application in regenerative medicine. Here we summarize the multipotent properties and the plasticities of MenSCs and other endometrial stem cells from recent studies conducted both in vitro and in vivo.  相似文献   

12.
This paper aims to screen and identify sphere clone cells with characteristics similar to cancer stem cells in human gallbladder cancer cell line GBC-SD. GBC-SD cells were cultured in a serum-free culture medium with different concentrations of the chemotherapeutic drug cisplatin for generating sphere clones. The mRNA expressions of stem cell-related genes CD133, OCT-4, Nanog, and drug resistance genes ABCG2 and MDR-1 in sphere clones were detected by quantitative real-time polymerase chain reaction (PCR). Stem cell markers were also analyzed by flow cytometry and immunofluorescent staining. Different amounts of sphere clones were injected into nude mice to test their abilities to form tumors. Sphere clones were formed in serum-free culture medium containing cisplatin (30 μmol/L). Flow cytometry results demonstrated that the sphere clones expressed high levels of stem cell markers CD133+ (97.6%) and CD44+ (77.9%) and low levels of CD24+ (2.3%). These clones also overexpressed the drug resistance genes ABCG2 and MDR-1. Quantitative real-time PCR showed that sphere clones expressed stem cell genes Nanog and OCT-4 284 and 266 times, respectively, more than those in the original GBC-SD cells. Immunofluorescent staining showed that sphere clones overexpressed OCT-4, Nanog, and SOX-2, and low expressed MUC1 and vimentin. Tumor formation experiments showed that 1×103 sphere clone cells could induce much larger tumors in nude mice than 1×105 GBC-SD cells. In conclusion, sphere clones of gallbladder cancer with stem cell-like characteristics can be obtained using suspension cultures of GBC-SD cells in serum-free culture medium containing cisplatin.  相似文献   

13.
1IntroductionNeural stemcells(NSCs)are a subtype of progenitorcells in the nervous systemthat can differentiate intoneurons and glia[1-3].Due to their feature of self-re-newal,NSCs have expectations for treatment of ner-vous system diseases such as Parkin…  相似文献   

14.
Objective: In this paper we compared the two methods of cell sorting (magnetic cell sorting and flow cytometry sorting) for the isolation and function analysis of mouse CD4~+ CD25~+ regulatory T (Treg) cells, in order to inform further studies in Treg cell function. Methods: We separately used magnetic cell sorting and flow cytometry sorting to identify CD4~+ CD25~+ Treg cells. After magnetic cell separation, we further used flow cytometry to analyze the purity of CD4~+ CD25~+ Treg cells, trypan blue staining to detect cell viability, and propidium iodide (PI) staining to assess the cell viability. We detected the immune inhibition of CD4~+ CD25~+ Treg cells in the in vitro proliferation experiments. Results: The results showed that compared to flow cytometry sorting, magnetic cell sorting took more time and effort, but fewer live cells were obtained than with flow cytometry sorting. The CD4~+ CD25~+ Treg cells, however, obtained with both methods have similar immunosuppressive capacities. Conclusion: The result suggests that both methods can be used in isolating CD4~+ CD25~+ Treg cells, and one can select the best method according to specific needs and availability of the methodologies.  相似文献   

15.
Embryonic stem(ES)cells are widely used for different purposes,including gene targeting,cell therapy,tissue repair,organ regeneration,and so on.However,studies and applications of ES cells are hindered by ethical issues regarding cell sources.To circumvent ethical disputes,great efforts have been taken to generate ES cell-like cells,which are not derived from the inner cell mass of blastocyst-stage embryos.In 2006,Yamanaka et al.first reprogrammed mouse embryonic fibroblasts into ES cell-like cells called induced pluripotent stem(iPS)cells.About one year later,Yamanaka et al.and Thomson et al.independently reprogrammed human somatic cells into iPS cells.Since the first generation of iPS cells,they have now been derived from quite a few different kinds of cell types.In particular,the use of peripheral blood facilitates research on iPS cells because of safety,easy availability,and plenty of cell sources.Now iPS cells have been used for cell therapy,disease modeling,and drug discovery.In this review,we describe the generations,applications,potential issues,and future perspectives of iPS cells.  相似文献   

16.
目的:从新生SD大鼠脑室下区分离并培养神经干细胞.观察其生长、增殖及分化.方法:采取无血清培养和单细胞克隆技术.采用原代贴壁及传代悬浮方法.培养获得细胞克隆.利用免疫细胞化学方法鉴定神经干细胞.结果:从新生SD大鼠脑室下区分离的组织,经原代和传代培养均可形成细胞克隆.且具有增殖能力.原代和传代细胞巢蛋白(Nestin)、神经元特异性烯醇化酶(Neuron specific enolase.NSE)抗原呈阳性.神经干细胞可分化为神经元.结论:用上述方法分离的细胞具有自我更新能力和分化潜能以及很强的增殖能力.属于中枢神经系统的干细胞.  相似文献   

17.
Stem cells constitute an important class of cells in the body that have the ability to perpetuate themselves and remain in an uncommitted state by a process of self-renewal as well as to specialize into new cell types. Their ability to differentiate into multiple cell types marks the tremendous potential of stem cells for tissue repair and organ regeneration. Realization of this potential is rapidly opening up unexplored avenues for curing several ailments including diabetes and neurodegenerative diseases. However, very little is understood about the basic biology of stem cells. For example, what are the biochemical tags that allow us to identify stem cell? Which are the signaling pathways that regulate their function? How does the environment (niche) influence major decisions made by stem cell? Is stem cell therapy the end to all woes, or is there a flip side to the story? This article aims to give an overview of the current status of stem cell research and raises some alarming issues related to stem cell-based therapies.  相似文献   

18.
目的从昆明鼠睾丸中克隆Bmi1基因,构建真核表达载体,并转染支持细胞,以便用作培养精原干细胞(SSCs)的滋养层.方法以5日龄昆明鼠为材料,提取小鼠睾丸组织中总RNA后,以RT-PCR技术克隆小鼠睾丸Bmi1基因,构建真核表达载体,并转染TM4细胞(睾丸支持细胞株),在转染后40 h进行免疫荧光鉴定.结果成功克隆小鼠睾丸Bmi1基因的cDNA,测序正确;免疫荧光细胞染色显示,转染后的支持细胞中有Bmi1蛋白表达.结论本研究为以转染了Bmi1基因的支持细胞作饲养层培养SSCs奠定了基础.  相似文献   

19.
研究了温压工艺对316L不锈钢粉末的生坯性能和烧结性能的影响.试验结果表明:温压工艺能够较大幅度地提高316L不锈钢粉末的生坯密度和生坯强度,也能提高其烧结后的密度和抗拉强度.如在700MPa的压制压力下,316L的温压生坯密度比冷压提高了0.19g/cm3,生坯强度比冷压提高了50%;在1150℃真空烧结后,温压坯的烧结密度比冷压坯的高0.19g/cm3,抗拉强度比冷压的提高了34MPa.  相似文献   

20.
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