细胞培养技术及避免污染的方法

细胞培养技术是医学研究过程中不可或缺的技术手段,也是分子生物学研究的主要方法手段。主要介绍细胞培养过程中的几种基本技术方法,细胞培养过程中的常见污染的来源、起因,并阐述了避免污染的方法,为细胞培养操作者提供参考。     

Inhibition of preadipocyte differentiation by Lycium barbarum polysaccharide treatment in 3T3-L1 cultures

BackgroundLycium barbarum (also called wolfberry), a famous Chinese traditional medicine and food ingredient, is well recognized for its significant role in preventing obesity; however, the molecular mechanisms underlying its preventive effects on fat accumulation are not well understood yet. The aim of this study was to determine the effects and mechanism of Lycium barbarum polysaccharides (LBP) on the proliferation and differentiation of 3T3-L1 preadipocytes. MTT was used to detect the proliferation of 3T3-Ll preadipocytes. Oil red O staining and colorimetric analysis were used to detect cytosolic lipid accumulation during 3T3-L1 preadipocyte differentiation. Real-time fluorescent quantitative PCR (qPCR) technology was used to detect peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), adipocyte fatty-acid-binding protein (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL) expression.ResultsThe concentration of LBP from 25 to 200 μg/mL showed a tendency to inhibit the growth of preadipocytes at 24 h, and it inhibited the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner. In the preadipocytes treated with 200 μg/mL LBP, there were reduced lipid droplets in the cytoplasm, and its effect was opposite to that of rosiglitazone (ROS), which significantly reduced the PPARγ, C/EBPα, aP2, FAS, and LPL mRNA expression of adipocytes.ConclusionsLBP exerts inhibitive effects on the proliferation and differentiation of 3T3-L1 preadipocytes and decreases the cytoplasm accumulation of lipid droplets during induced differentiation of preadipocytes toward mature cells. Above phenomenon might link to lowered expression of PPARγ, C/EBPα, aP2, FAS, and LPL after LBP treatment. Thus, LBP could serve as a potential plant extract to treat human obesity or improve farm animal carcass quality via adjusting lipid metabolism.How to cite: Xu X, Chen W, Yu S, et al. Inhibition of preadipocyte differentiation by Lycium barbarum polysaccharide treatment in 3T3-L1 cultures. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2021.01.003     

细胞永生化技术在体育领域研究的可行性分析

目前细胞生物学技术迅猛发展,使优秀运动员细胞＂永生化＂成为可能。这在根本上解决了寻找抑制人类运动能力基因研究的接力式进行和标本的暂时性的采集中存在的矛盾,介绍永生化技术在体育研究中的进展,旨为在寻找和提高影响人类运动能力基因方面提供可行性的研究方法。     

一种基于J2ME的手机视频监控系统

手机视频监控系统伴随着3G的兴起有着广阔的发展空间,随时随地的视频监控也能方便人们的工作和生活。通过研究视频监控相关方面的关键技术,设计了一种基于J2ME的手机视频监控系统,然后实现了该系统的视频服务器的搭建,实现了Web端的服务器管理功能并进行了手机客户端实时视频监控的测试,达到了设计的要求。     

Delivering MC3T3-E1 cells into injectable calcium phosphate cement through alginate-chitosan microcapsules for bone tissue engineering

研究目的：本研究应用海藻酸钠-壳聚糖微囊保护成骨细胞,接种到β-磷酸三钙/磷酸钙骨水泥（β-TCP/CPC）浆料中,使β-TCP/CPC骨修复材料具有一定的细胞活性,同时提高固化后材料的孔隙率和孔径,以最终实现提高β-TCP/CPC骨水泥的降解速度,加快成骨和骨修复。创新要点：本研究首次应用海藻酸钠-壳聚糖微胶囊包封成骨细胞与CPC浆料复合,复合后实现自动细胞释放,释放出的细胞具有良好的生物学活性。研究方法：（1）高压静电成囊法制备载小鼠成骨前体细胞（MC3T3-E1）的海藻酸钙和海藻酸钠-壳聚糖微胶囊;（2）微囊化MC3T3-E1细胞,进行体外培养,使用细胞计数试剂盒（CCK-8）检测细胞活性,并用钙黄绿素-AM（Calcein-AM）和碘化丙啶（PI）进行活死细胞双重染色;（3）微囊化MC3T3-E1细胞与β-TCP/CPC浆料复合培养后,激光共聚焦扫描显微镜和环境扫描电子显微镜观测细胞在材料上的释放、粘附,CCK-8法检测材料上细胞的活力,碱性磷酸酶（ALP）检测观察细胞的分化状况,茜素红染色观察释放细胞的矿化能力。重要结论：海藻酸钠-壳聚糖微胶囊可作为可注射磷酸钙骨水泥内部接种成骨细胞并实现细胞释放的良好载体,释放出的成骨细胞具有良好的生物学活性。     

生物工程专业双语课程考试改革探索与实践

以细胞生物学双语课程的考试改革实践为例子,分析集美大学生物工程专业双语课程考试存在的问题,对综合性全程式考试模式进行探索与实践,总结改革的效果,并尝试探索今后课程改革的方向。     

咖啡与运动

1995年6月,国务院颁布《全民健身计划纲要》,随着此纲要的颁布,当今人们对体育运动是越来越重视。然而运动必将产生疲劳,随着自由基理论引入运动医学领域之后,运动与自由基已成为人们关注的课题。最近一些科学研究也恰巧证明了咖啡有利于清除自由基。同时为竞技运动员的疲劳恢复开辟了新的出路。本文就咖啡与运动性疲劳和机体细胞的损伤这一问题进行简要综述。     

Say Goodbye…Let's Roll: The Social Dynamics of Wireless Networks on September 11

This article describes the use of wireless telecommunication media within the different locations directly affected by the hijackings on September 11. Comparisons across these different contexts provides an empirical anchor to more general themes concerning the social dynamics of wireless in the unfolding events of this day. An indication is given of how the important social role of wireless phones in this crisis could redefine public views on wireless media and thereby shape policy and regulation in the years ahead.     

Arachnoid cell involvement in the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage

Objective: To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid (CSF), and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage (SAH). Methods: Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR (HLA-DR). Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry (FCM). The variation of arachnoid cells' ultrastructure was observed by transmission electron microscope (TEM). Arachnoid cells were co-cultured with peripheral blood mononuclear cells (PBMCs). The content of soluble interleukin-2 receptor (sIL-2r) in culture medium was detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HLA-DR was distributed in cytoplasm and not in the karyon. (2) After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was (2.5±0.4)% at the first 5 d, increasing to (60.8±3.6)% on Day 7. (3) After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic reticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. (4) Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of sIL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of sIL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions: (1) Basic HLA-DR expression is present in arachnoid cells. (2) After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells (APCs) and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH.