脉冲电磁场对体外培养成骨细胞的影响

脉冲电磁场影响体外培养的成骨样细胞,促使其增殖、分化、并加速骨样组织形成,对成骨细胞形态学上也有一定影响,本文综述近年来国内外在电磁场对成骨细胞作用方面的一些研究进展.     

脉冲电磁场对破骨细胞和成骨细胞前体细胞作用的研究

目的 研究脉冲电磁场（PEMFs）对破骨细胞和成骨细胞前体细胞的作用。方法单独离体PEMFs作用：取8周龄雌性SD大鼠股骨骨髓细胞,根据PEMFs作用方式分为4个剂量组和对照组．分别进行成纤维细胞集落形成单位（CFU—F）和粒／巨噬细胞集落形成单位（CFU—GM）培养观察。活体结合离体PEMFs作用：取8周龄雌性SD大鼠随机分为3组：2—70组、OVX组和SHAM组,其中2．70组．OVX组进行双侧卵巢切除手术,SHAM组不切除卵巢。术后12周对2—70组大鼠进行PEMFs作用,OVX组和SHAM组不进行PEMFs作用。作用结束后,取大鼠股骨骨髓。根据体外培养过程中是否继续接受PEMFs作用,分为2—70PEMFs作用组／未作用组、OVXPEMFs作用组侏作用组、SHAMPEMFs作用组／未作用组,分别进行CFU．F和CFU．GM培养观察。结果单独离体PEMFs作用时,与对照组相比,4个剂量组的CFU-GM减少,CFU．F增加;活体结合离体PEMFs作用时,剂量组的CFU—F均增加,而CFU—GM各组间均无显著差异。结论单独离体PEMFs作用时,PEMFs对体外培养的破骨细胞前体细胞有抑制作用,对成骨细胞前体细胞增殖有促进作用;活体结合离体PEMFs作用时,PEMFs对成骨细胞前体细胞增殖有促进作用,但未见对破骨细胞前体细胞的抑制作用。     

极低频脉冲电磁场对新生大鼠成骨细胞的影响

目的：观察极低频脉冲电磁场（pulsed electromagnetic fields，PEMF）对体外培养成骨细胞增殖、分化、体外矿化的影响。方法：采用频率为15Hz、强度为5mT、占空比为15％的PEMF作用于成骨细胞，检测成骨细胞的增殖、碱性磷酸酶（alkaline phosphatase，ALP）活性以及体外矿化指标。结果与结论：PEMF显著促进成骨细胞增殖和体外矿化，抑制ALP活性作用。     

电磁场对骨组织和成骨细胞的作用

电学环境是骨组织所处的重要微环境之一，外加电磁场对骨组织和成骨细胞有重要作用。临床上电磁场已被用于治疗骨折、骨不连、骨质疏松等骨科病症，并已取得满意的效果。本综述了电磁场对骨组织和成骨细胞的影响及机理，并对电磁场对骨组织工程化培养的意义进行了探索。     

电磁场对骨组织和成骨细胞的作用

电学环境是骨组织所处的重要微环境之一 ,外加电磁场对骨组织和成骨细胞有重要作用。临床上电磁场已被用于治疗骨折、骨不连、骨质疏松等骨科病症 ,并已取得满意的效果。本文综述了电磁场对骨组织和成骨细胞的影响及机理 ,并对电磁场对骨组织工程化培养的意义进行了探索     

应力、极低频脉冲电磁场与成骨细胞

电磁与机械环境能够影响成骨细胞的生长与分化,关于其作用机理的研究每年都有大量的相关报道,主要针对细胞内的钙过程综述了极低频电磁场与机械因子对成骨细胞的作用途径,并对它们之间的异同进行了比较。     

不同占空比低强度脉冲电磁场对大鼠成骨细胞的影响

目的：研究磁感应强度为1mT、频率为15Hz不同占空比的脉冲电磁场（pulsedelectromagneticfields,PEMFs）对体外培养大鼠成骨细胞增殖与细胞分化的影响。方法：取新生SD大鼠仔鼠头盖骨,用骨组织块培养法分离成骨细胞,培养至第3代后,分另q对其进行场强1mT、频率15Hz,占空比10％、20％、40％、60％的脉冲电磁场作用,8h／d,持续作用3d．应用MTT法、碱性磷酸酶测定检测成骨细胞增殖、分化情况。结果：不同占空比PEMFs对大鼠成骨细胞增殖与分化影响程度不同,20％、40％和60％占空比组显著提高成骨细胞增殖水平（P〈0．05）,其中40％和60％占空比组作用效果最显著（P〈0．01）。10％、20％、40％和60％占空比组均能促进成骨细胞分化（P〈0．05）,其中以60％占空比组的效果最为明显fP〈O．01）。结论：本研究进一步证实了低强度PEMFs能够促进成骨细胞的增殖与分化,并且PEMFs对成骨细胞的影响依赖于占空比参数的选择．而且有可能存在“占空比”窗口。     

脉冲电磁场对细胞作用的特异性研究

本文研究了脉冲电磁场（ＥＭＦ）对细胞作用的特异性，并初步探索了作用机理。     

脉冲电磁场对细胞的特异性作用研究

本文研究了脉冲电磁场（ＥＭＰ）对细胞作用特异性，并初步探讨了作用机理。     

脉冲电磁场对成骨和破骨代谢的影响*

背景：脉冲电磁场对成骨细胞、破骨细胞、骨基质合成均有明显作用。 目的：旨在探究脉冲电磁场在成骨和破骨代谢中的作用以及治疗骨质疏松的机制,以促进其临床应用。 方法：由第一作者应用计算机检索PubMed、中国期刊全文数据库(CNKI)、维普数据库和万方数据库1997-05/2011-08相关文献。在标题、摘要、关键词中以“pulsed electromagnetic field(PEMFs),bone metabolism,osteoporosis,osteoblast,osteoclast ,bone marrow mesenchymal stem cells(BMMSCs)”或“脉冲电磁场,骨代谢,骨质疏松,成骨细胞,破骨细胞,骨髓间充质干细胞”为检索词进行检索。选择文章内容与脉冲电磁场有关者,同一领域文献则选择近期发表在权威杂志文章进行分析。 结果与结论：初检得到389篇文献,根据纳入标准选择关于假体无菌性松动分析及处理的46篇文献进行综述。脉冲电磁场可促进成骨代谢,抑制破骨代谢,参与调节转化生长因子β,白细胞介素6等骨代谢相关的细胞因子,促进骨基质形成,改善骨生长微环境,对骨髓间充质干细胞的增殖分化亦有促进作用。推测脉冲电磁场治疗骨质疏松及其并发症有重要的临床价值。     

The effect of pulsed electromagnetic fields on chondrocyte morphology

Osteoarthritis is a debilitating joint disease where the articular cartilage surface degrades and is unable to repair itself through natural processes. Chondrocytes reside within the cartilage matrix and maintain its structure. We conducted in vitro experiments to investigate the morphological response of cultured human chondrocytes under different pulsed electromagnetic field (PEMF) conditions. In the control experiments, cultured chondrocytes attached to the bottom of a culture dish typically displayed either a stellate or spindle morphology with extended processes. Experimental chondrocyte cultures were placed in a Helmholtz coil to which a ramp waveform was applied. Exposure to PEMFs caused the chondrocytes to retract their processes, becoming spherical in shape. This change in morphology followed a progression from stellate to spindle to spherical. These morphological changes were reflected in an average reduction of 30% in the surface contact area of the chondrocytes to the culture dish. Understanding the mechanisms by which PEMFs affect the morphology of chondrocytes will help lead to new treatments for osteoarthritis.     

脉冲电磁场辅助骨细胞培养装置的研制

目的 根据脉冲电磁场对骨细胞的作用机制,设计了能够产生均匀磁场、参数可调的脉冲电磁场发生装置和磁场作用板;叙述了实验装置的硬件构成、软件控制功能以及磁场作用板的设计,并通过试验测试,观察记录了在未加入磁性材料和加入磁性材料后磁场的分布情况.方法 设计了强度为4～6 mT、频率8 Hz的参数可调的脉冲电磁场发生装置和专用的适合细胞培养的磁场作用装置,并对产生的磁场进行了实验测定.结果 实验装置运行时,对各参数检测表明,实验装置满足设计的要求:在加入磁性材料后,磁场作用表面的磁场分布均匀.结论 实验装置满足设计要求,可为进一步进行骨细胞培养提供可靠的实验手段.     

The effects of pulsed electromagnetic field on the functions of osteoblasts on implant surfaces with different topographies

The use of pulsed electromagnetic fields (PEMFs) is a promising approach to promote osteogenesis. However, few studies have reported the effects of this technique on the osseointegration of endosseous implants, especially with regard to different implant topographies. We focused on how the initial interaction between cells and the titanium surface is enhanced by a PEMF and the possible regulatory mechanisms in this study. Rat osteoblasts were cultured on three types of titanium surfaces (Flat, Micro and Nano) under PEMF stimulation or control conditions. Protein adsorption was significantly increased by the PEMF. The number of osteoblasts attached to the surfaces in the PEMF group was substantially greater than that in the control group after 1.5 h incubation. PEMF stimulation oriented the osteoblasts perpendicular to the electromagnetic field lines and increased the number of microfilaments and pseudopodia formed by the osteoblasts. The cell proliferation on the implant surfaces was significantly promoted by the PEMF. Significantly increased extracellular matrix mineralization nodules were observed under PEMF stimulation. The expression of osteogenesis-related genes, including BMP-2, OCN, Col-1,ALP, Runx2 and OSX, were up-regulated on all the surfaces by PEMF stimulation. Our findings suggest that PEMFs enhance the osteoblast compatibility on titanium surfaces but to different extents with regard to implant surface topographies. The use of PEMFs might be a potential adjuvant treatment for improving the osseointegration process.     

Attenuation of interleukin-1beta by pulsed electromagnetic fields after traumatic brain injury

Traumatic Brain Injury (TBI) is a major cause of morbidity and mortality in civilian and military populations. Interleukin-1beta (IL-1β) is a pro-inflammatory cytokine with a key role in the inflammatory response following TBI and studies indicate that attenuation of this cytokine improves behavioral outcomes. Pulsed electromagnetic fields (PEMF) can reduce inflammation after soft tissue injuries in animals and humans. Therefore, we explored whether PEMF signals could alter the course of IL-1β production in rats subjected to closed-head contusive weight-drop injuries (Marmarou method) and penetrating needle-stick brain injuries. Protein levels, measured by the Biorad assay, were not altered by injuries or PEMF treatment. In addition, we verified that IL-1β levels in cerebrospinal fluid (CSF) were proportional to injury severity in the contusion model. Results demonstrate that PEMF treatment attenuated IL-1β levels up to 10-fold in CSF within 6 h after contusive injury and also significantly suppressed IL-1β within 17–24 h after penetrating injury. In contrast, no differences in IL-1β were seen between PEMF-treated and control groups in brain homogenates. To the authors’ knowledge, this is the first report of the use of PEMF to modulate an inflammatory cytokine after TBI. These results warrant further studies to assess the effects of PEMF on other inflammatory markers and functional outcomes.     

电场和电磁场治疗骨折不愈合

电场和电磁场在临床上用于治疗骨折不愈合已有三十多年的历史。本文对其临床应用现状、存在问题及未来研究方向给予了介绍。     

脉冲电场和磁场对高血粘影响的比较研究

比较研究脉冲电场和脉冲磁场对高血粘的影响,探索能否利用脉冲电场或脉冲磁场降低血液粘度,改善血循环。每份血样等分9份,1份作对照,对另外8份分别作不同的脉冲电场或脉冲磁场处理。高血粘血样经△B/△t为2.5×105(Ts-1)的脉冲磁场作用后,全血表观粘度η降低(P<0.01)、红细胞电泳率EPM加快(P<0.01),血沉速率ESR提高(P<0.01)。脉冲磁场能改善高血粘血样的流变特性。     

PD98059对人骨髓间质干细胞分化为成骨细胞的影响

目的:探讨胞外信号调节激酶(ERK)信号传导途径对骨髓间质干细胞(MSC)分化为成骨细胞的影响。方法:采用Ficoll-Paque淋巴细胞分离液分离成人MSC,体外扩增,应用地塞米松、β-甘油磷酸钠、vitaminC定向诱导MSC分化为成骨细胞。在成骨诱导液中加入不同剂量的PD98059,观察其对成骨细胞形成的影响。结果:MSC体外扩增15代可获得(3-4)×10¹²个细胞。在成骨诱导液作用下,MSC可在体外定向分化为成骨细胞。不同剂量的PD98059均可抑制MSC分化为成骨细胞,并有剂量依赖关系;同时促使部分细胞转化为脂肪细胞。结论:ERK信号传导途径可能在MSC分化为成骨细胞和脂肪细胞过程中起关键作用。     

电磁场细胞生物效应研究进展

随着科学和技术的发展,人们越来越多地暴露于各种设备产生的电磁场中,电磁场对生物体影响的研究越来越受到人们的重视。在这些研究中,最基础的研究之一是电磁场对生命基础——细胞作用的研究。本文对电磁场对生物体(人体)、细胞及更微观层次作用的研究的最新动态进行了综述。