植物细胞程序化死亡的研究进展述要

细胞程序化死亡是普遍发生于植物生长发育的各个阶段的种生物现象。植物编程性细胞死亡或细胞程序化死亡（Programmed Celldeath,PCD）的研究早在80年代就开始了,90年代初Greenberg提出在植物对病原体的防御反应中存在类似动物细胞的程序性死亡现象。此后植物PCD现象引起了人们的重视,并成为当前生物学研究的热点。本文对植物器官发生了细胞程序化死亡现象、植物细胞程序化死亡相关的基因研究方法以及针对PCD的概念、研究进展、方法及研究意义等方面进行了简要概述。     

运动与细胞凋亡综述

细胞凋亡是多细胞动物生命活动过程中不可缺少的组成部分,维持着生物细胞生存和死亡间的平衡。无论是低等动物还是高等动物都会如此。哺乳动物的受精、胚胎发生、发育和成熟的过程,构成了组织细胞生死交替,保证了个体发育成熟,是动物存活的需要,也贯穿于动物全部寿命周期。     

转基因植物生物反应器的研究进展

叙述了利用转基因植物作为生物反应器生产重组药物蛋白的研究和商业化现状及其发展趋势,并对其表达和纯化策略以及表达效率的提高作了讨论.     

激发子诱导植物基因表达研究进展

介绍了基因诱导表达调控的研究方法，并概述了与ABA，乙烯，真菌激发子诱导表达相关的顺式作用元件（G-box,GT-1结合位点，GCC－blox,W-box)，以及与这些顺式作用元件相互作用的转录因子（GBFS，GT－1，EREBPS，WRKY）。同时对植物基因诱导表达调控的分子机制作了综述。     

低温保存对Hep-G2细胞凋亡的影响

样本质量是体现生物样本库价值的关键,但是低温保存可能导致细胞凋亡及基因表达量的变化,影响样本质量。本文采用流式细胞术与实时荧光定量PCR(qPCR)的方法,研究了Hep-G2细胞在不同条件下冻存后凋亡及相关基因表达量。结果表明:低温保存影响Hep-G2细胞的成活率、凋亡情况及某些凋亡基因表达量。无论冻存过程中是否添加低温保护剂,低温保存都会对细胞的凋亡相关基因表达带来不同程度的影响。不添加保护剂冻存会导致细胞死亡,添加10%DMSO冻存会导致细胞凋亡,复苏培养24 h后细胞的成活率、凋亡情况与相关基因表达量基本与对照组水平一致。     

动脉硬化平滑肌细胞增殖和凋亡及其调节

为阐明动脉粥样硬化（ＡＳ）斑块发展与稳定的内在机制，围绕动脉增生内膜、ＡＳ斑块内平滑肌细胞（ＳＭＣ）增殖和凋亡密切相关的即刻早期基因（ｃ－ｆｏｓ、ｃ－ｊｕｎ、ｃ－ｍｙｃ）和相关基因（ｐ５３、ｂｃｌ－２、ｃ－ｓｉｓ）表达失衡和重调这一中心展开研究，提出血管ＳＭＣ增殖和凋亡是决定ＡＳ斑块发展的关键环节。     

扇贝多肽(PCF)抑制紫外线诱导的HaCaT细胞凋亡

建立了紫外线A和B辐射诱导的永生化角质形成细胞(HaCaT)凋亡的模型,采用四甲基偶氮唑盐法、琼脂糖凝胶电泳、流氏细胞仪、酶化学方法和蛋白印迹等技术,研究了扇贝多肽(PCF)抑制紫外线诱导HaCaT细胞凋亡的分子机制。实验发现,PCF可明显抑制紫外线A和B诱导的HaCaT细胞凋亡。1.42~5.68mM剂量范围内PCF剂量依赖性抑制紫外线诱导的HaCaT细胞内活性氧的生成,并能提高细胞内抗氧化酶活性,增强细胞总抗氧化能力,减少脂质过氧化产物的产生;同时,PCF也抑制细胞内JNK蛋白的磷酸化及Caspases-3蛋白的活化。通过加入ROS、JNK和Caspase-3抑制剂证实,PCF作为抗氧化剂减少了细胞内ROS的生成并提高了细胞内抗氧化酶活性,进而阻断了ROS→JNK→Cas-pase-3信号级联反应,抑制了紫外线辐射诱导的HaCaT细胞凋亡。     

植物基因工程研究进展

植物基因工程研究进展贾士荣植物基因工程是生物技术中一项快速发展的新技术，运用这种技术可定向创造出高产、优质、抗逆的植物新品种，大幅度提高作物产量，因而对未来农业的发展将起重要的作用。植物基因工程以重组ＤＮＡ技术、细胞和组织培养为基础，克服常规育种中有...     

植物细胞抗重金属伤害的分子机制研究进展

植物细胞抗重金属伤害的分子机制主要涉及金属离子高的吸收、运输、区域化及螯合作用等方面,其中跨膜运载蛋白的表达、调控对重金属超富集起了关键作用。金属阳离子运载蛋白家族主要包括CDF家族、NRAMP家族和ZIP家族。综述了近年来研究重金属超富集植物吸收、转运和贮存zn、M、cd等重金属的分子机制所取得的主要进展。     

Apoptosis goes on a chip: advances in the microfluidic analysis of programmed cell death

Recent years have brought enormous progress in cell-based lab-on-a-chip technologies, allowing dynamic studies of cell death with an unprecedented accuracy. As interest in the microfabricated technologies for cell-based bioassays is rapidly gaining momentum, we highlight the most promising technologies that provide a new outlook for the rapid assessment of programmed and accidental cell death and are applicable in drug discovery, high-content drug screening, and personalized clinical diagnostics.     

The influence of the surface chemistry of silver nanoparticles on cell death

The influence of the surface chemistry of silver nanoparticles (AgNPs) on p53 mediated cell death was evaluated using human dermal fibroblast (HDF) and lung cancer (A549) cells. The citrate reduced AgNPs (C-AgNPs) were modified with either lactose (L-AgNPs) or a 12-base long oligonucleotide (O-AgNPs). Both unmodified and modified AgNPs showed increased concentration and time dependent cytotoxicity and genotoxicity causing an increased p53 up-regulation within 6 h and led to apoptotic or necrotic cell deaths. The C-AgNPs induced more cytotoxicity and cellular DNA damage than the surface modified AgNPs. Modifying the C-AgNPs with lactose or the oligonucleotide reduced both necrotic and apoptotic cell deaths in the HDF cells. The C-AgNPs caused an insignificant necrosis in A549 cells whereas the modified AgNPs caused necrosis and apoptosis in both cell types. Compared to the O-AgNPs, the L-AgNPs triggered more cellular DNA damage, which led to up-regulation of p53 gene inducing apoptosis in A549 cells compared to HDF cells. This suggests that the different surface chemistries of the AgNPs cause different cellular responses that may be important not only for their use in medicine but also for reducing their toxicity.     

Methodical Failure Analysis and programmed investigation course to increase the safety of structural parts and plants

To increase the safety of machines and plants, a systematic failure analysis must be integrated into the technical development. The methodic of a failure analysis is described, which is based on the construction methodology, which has been developed during the past few years. To effect a methodical failure analysis, considerations on stresses and stress reactions must be carried out. Failure characteristics and failure mechanisms are identified uniformly and brought into a standardized combination. Based on these conditions it is possible to programme the working method of the failure analysis. Finally the working method described permits a standardized and comparable storage and evaluation of failure data.     

863海洋生物技术青年基金项目研究取得进展

海洋生物技术青年基金课题研究取得可喜进展。这些课题是 :“转基因微藻高密度高表达培养技术研究” ,解决了转ＭＴ基因微藻培养过程中ＭＴ表达量测定的ＥＬＩＳＡ方法 ,进行了转ＭＴ基因集胞藻 680 3和野生藻自培养、混合培养和光合放氧特性研究。“海带硫酸多糖的结构分析及其生理活性的研究”进行了海带硫酸多糖的分级及主要组分的结构解析、抗氧化特性和抗肿瘤作用的研究。完成了岸藻聚糖硫酸酯生产的中试技术 ,利用该项目生产技术 ,山东洁晶集团份有限公司已成功地生产出了 50 0 0公斤的岩藻聚糖硫酸酯产品 ,产值达 350 0万元 ,并全部…     

Progression of failure in fiber-reinforced materials

Decohesion is an important failure mode associated with fiber-reinforced composite materials. Analysis of failure progression at the fiber-matrix interfaces in fiber-reinforced composite materials is considered using a softening decohesion model consistent with thermodynamic concepts. In this model, the initiation of failure is given directly by a failure criterion. Damage is interpreted by the development of a discontinuity of displacement. The formulation describing the potential development of damage is governed by a discrete decohesive constitutive equation. Numerical simulations are performed using the direct boundary element method. Incremental decohesion simulations illustrate the progressive evolution of debonding zones and the propagation of cracks along the interfaces. The effect of decohesion on the macroscopic response of composite materials is also investigated.     

浅谈ISO9000质量管理体系在膜厂的应用

扼要地叙述了ISO9000质量管理体系的八大质量管理原则在薄膜工厂的运用,以及如何与企业经营管理相结合,指出质量管理体系与企业其它管理体系融合的重要性。     

生物降解包装塑料研究进展

生物降解包装塑料是一种绿色包装塑料,生物降解法是一种很好解决废弃包装塑料的新方法.介绍了生物降解包装塑料的种类,分析了生物降解包装塑料的机理,综述了生物降解包装塑料的研究进展,指出了生物降解包装塑料的发展趋势.     

Bio-inspired melanin nanoparticles induce cancer cell death by iron adsorption

Dysregulation of iron metabolism is a common characteristic of cancer cells. The rapid proliferation of the tumour cells means that there is an increased dependence upon iron compared to healthy cells. Chelation of iron can be undertaken with a number of different compounds, however, simply lowering systemic iron levels to control tumour growth is not possible since iron is essential for cellular metabolism in the rest of the body. Nanoparticulate iron chelators could overcome this difficulty by targeting to the tumour either by the passive enhanced permeation and retention effect, or by targeting ligands on the surface. Nanoparticles were prepared from melanin, which is a naturally occurring pigment that is widely distributed within the body, but that can chelate iron. The prepared nanoparticles were shown to be ~220?nm, and could adsorb 16.45?mmoles iron/g melanin. The nanoparticles showed no affect on control fibroblast cells at a concentration of 200?μM, whereas the immortalised cancer cell lines showed at least 56% reduction in cell growth. At a concentration of 1?mM melanin nanoparticles the cell growth could be reduced by 99% compared to the control. The nanoparticles also show no significant haemotoxicity, even at concentration of 500?μM. Melanin nanoparticles are therefore a viable prospect for destroying cancer cells via iron starvation.

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