茧蜂病毒上调ROS促进昆虫细胞凋亡的研究

茧蜂病毒(Microplitis bicoloratus bracovirus, MbBV)存在于鳞翅目茧蜂科寄生蜂雌蜂输卵管萼上皮细胞中,对寄生蜂成功寄生寄主起着至关重要的作用.活性氧(reactive oxygen species,ROS)主要是由细胞内线粒体等细胞器产生的活性分子,广泛参与和调节机体的各种生理和病理过程;为了探究ROS在茧蜂病毒诱导昆虫细胞凋亡过程中的作用,研究通过体内和体外细胞实验探讨了茧蜂病毒在感染细胞过程中ROS变化与细胞凋亡变化的关系.结果显示,茧蜂的寄生导致斜纹夜蛾幼虫血细胞ROS上调,凋亡增加.提取茧蜂病毒MbBV感染Spli221细胞24 h后,细胞内的ROS水平显著上调的同时也伴随着细胞凋亡增加,而当用ROS抑制剂NAC抑制ROS产生时,则可以挽救MbBV诱导的细胞凋亡.以上结果提示,MbBV可能通过促进ROS的产生来诱导细胞凋亡的发生.     

细胞凋亡与病毒感染

病毒感染细胞后通过其自身基因的表达或激活宿主细胞凋亡相关基因,启动或抑制细胞凋亡.研究病毒与细胞的相互关系,有助于深入理解病毒的致病机理,为病毒性疾病的预防、治疗和诊断提供相应对策.     

细胞凋亡与心血管疾病

目的：评价细胞凋亡与心血管疾病的关系．方法：查阅文献，综合论点．结果：细胞凋亡过程涉及多种心血管疾病．结论：细胞凋亡的形态特征、细胞凋亡的生化过程及其细胞凋亡的诱导因素和基因调控机理的发现，为揭示心血管疾病的发病机制及寻找生物学防治提供了新的思路．     

细胞凋亡与肿瘤治疗

细胞凋亡与许多疾病特别是肿瘤的发生发展有关，许多癌基因与抑癌基因参与细胞凋亡过程。对细胞凋亡以及在肿瘤治疗中的有关系进行了综述。     

PI3K-Akt和JNK信号通路抑制剂对杆状病毒诱导昆虫细胞凋亡影响的初步研究

为了探讨杆状病毒诱导昆虫细胞凋亡通路与细胞内PI3K-Akt和JNK信号通路的关系,应用PI3K的特异性抑制剂Wortmannin和JNK的特异性抑制剂SP600125处理芹菜夜蛾核型多角体病毒(AfMNPV)感染的斜纹夜蛾SL-1细胞,研究了这些抑制剂对杆状病毒诱导昆虫细胞凋亡的影响.分别使用浓度梯度2.5,25,50μmol的SP600125和0.3,3,30μmol的Wortmannin处理感染了SfaMNPV的SL-1细胞,24h后进光镜观察、DAPI荧光染色,流式细胞术分析显示,抑制PI3K-Akt和JNK信号通路后杆状病毒诱导的细胞凋亡受到明显影响,细胞凋亡水平明显降低.研究结果提示AfMNPV诱导斜纹夜蛾SL-1细胞凋亡过程可能涉及细胞PI3K-Akt和JNK信号通路.     

小鼠单纯疱疹病毒Ⅰ型心肌炎与心肌细胞凋亡和c-Myc蛋白表达的关系

为了探讨小鼠单纯疱疹病毒Ⅰ型心肌炎与心肌细胞凋亡和cMyc蛋白的表达的关系,给BALB/C小鼠腹腔接种单纯疱疹病毒Ⅰ型以诱发其急性病毒性心肌炎(VMC),感染病毒3～35天后,VMC检出率为91.67%。应用电镜、原位末端标记法(TUNEL)及免疫组化技术检测发现,感染鼠心肌中有细胞凋亡和cMyc蛋白的表达,二者阳性率分别为78.33%和81.67%,凋亡细胞阳性指数(AI)范围在34.14±11.56～26.41±10.2之间。细胞凋亡和cMyc蛋白可能参与VMC的发生与发展。     

人肝癌细胞移植瘤QGY—9204中细胞凋亡和坏死并存现象的初步分析

关于细胞凋亡和坏死的判别标准及其相互关系已逐渐成为研讨的热点。研究表明，ｐ５３基因的表达导致细胞凋亡，抑制肿瘤形成。在将Ａｄ／ｐ５３导入人肝癌细胞移植瘤ＱＧＹ－９２０４的研究中发现，实验组与对照组的移植瘤中均出现凋亡特征指标（ＤＮＡ梯型条带、凋亡小体等）。而离体增养的肝癌细胞ＱＧＹ－７７０３并未检出细胞凋亡现象。那么，实体瘤的ＤＮＡ梯型条带与凋亡和坏死有何关系？研究表明，瘤体内细胞凋亡和坏死并存，     

细胞凋亡与衰老关系的研究

文章阐述细胞凋亡与衰老、细胞凋亡与免疫衰老、细胞凋亡与心血管疾病、细胞凋亡与衰老相关疾病的关系及细胞凋亡在修复中的作用.     

腺病毒介导人MDA-7/IL-24基因对人鼻咽癌细胞CNE的凋亡作用

mda-7(melanoma differentiaton-associated gene 7,黑色素瘤分化相关基因7),其表达产物又称 IL-24(Interleukin-24,白介素24),现有实验证明其对多种肿瘤细胞有明显的生长抑制和凋亡诱导作用,具有广泛的癌症治疗前景和预期.鼻咽癌作为中国南方多发的癌症,目前少有mda-7对其凋亡作用的研究,本实验利用腺病毒载体(复制缺陷型)构建搭载mda-7的重组病毒Ad-mda7及空病毒Ad-GFP,用HEK 293T细胞对病毒进行扩增,得到的重组病毒用于人鼻咽癌细胞CNE的凋亡研究.Hoechst 33258凋亡染色以及流式细胞仪PI染色检测结果表明:重组病毒Ad-mda7相比空病毒Ad-GFP以及PBS处理组,对CNE细胞有较明显的凋亡诱导作用.     

人脊髓灰质炎病毒感染诱发Vero细胞凋亡的研究

用人脊髓灰质炎病毒分别感染Ｖｅｒｏ细胞和稳定表达ｐ３５基因的Ｖｅｒｏ３５细胞，经细胞核ＤＡＰＩ染色，细胞ＤＮＡ琼脂糖电泳笔ＴＤＴ生物素原位标记等方法证实病毒感染的细胞具有典型的凋亡细胞学特征和生物化学特征。     

Mitochondrial response and calcium ion change in apoptotic insect cells induced by SfaMNPV

Mitochondrial responses and changes of calcium ions in apoptotic insect SL-1 cells induced by Syngrapha falcifera multiple nuclear polyhedrosis virus (SfaMNPV) are reported in this paper. By using Rhodamine 123 as a fluorescent labeling probe, flow cytometry analysis and confocal laser scanning microscope observation we observed that the mitochondrial transmembrane potential (△ψm) began to decrease in SL-1 cells at 4 h post infection and △ψm reduced continuously with the extension of virus infection. Western blotting indicated that the Bcl-2 level in the mitochondria gradually declined and was down- regulated. Cells undergoing apoptosis were found to have an elevation of cytochrome c in the cytosol and a corresponding decrease in the mitochondria, which indicated that cytochrome c was released from mitochondria into cytosol. These results suggest that mitochondrion-mediated apoptotic signal transduction pathway exists in apoptotic insect cell induced by SfaMNPV. Cytosolic free calcium ([Ca^2 ]i) concentration rapidly increased after SfaMNPV infection and the elevated calcium was tested to come partly from extracelllular calcium ion influx. Flow cytometry analysis indicated that the apoptosis in SL-1 cells was not influenced by established cytosolic calcium clamped conditions and the EGTA inhibiting calcium influx. Therefore, neither the elevation of cytosolic calcium ion nor extracellular calcium entry was the inducing factor of apoptosis, which hinted that the depletion of ER Ca^2 store contributed to SL-1 cell apoptosis induced by SfaMNPV.     

扁平苔藓病因及发病机制的研究进展

目的：总结国内外对扁平苔藓病因及发病机制的研究进展.方法：应用检索PUBMED及CHKD期刊全文数据库检索系统,以＂扁平苔藓病因＂为关键词,检索近10年有关文献.结果：细胞介导的免疫反应,细胞分化标志分子的改变,病毒感染,神经精神因素及角质形成细胞的凋亡与扁平苔藓发病关系密切.结论：扁平苔藓病因复杂,最新研究提示其发病机制与细胞凋亡有关,值得我们进一步研究探讨.     

患包涵体肝炎鸡血淋巴细胞凋亡、坏死的研究

运用流式细胞仪技术研究了鸡包涵体肝炎(inclusion body hepatitis,IBH)发病过程中血液淋巴细胞的凋亡、坏死变化情况.结果表明,攻毒组在攻毒后3~5d,淋巴细胞早期凋亡显著下降(P<0.05),7d明显升高(P<0.05),12d时淋巴细胞早期凋亡下降显著(P<0.05).攻毒组在攻毒后3~5d时,淋巴细胞坏死与对照组差异不显著(P>0.05),7~12d时显著低于对照(P<0.05),在25d时显著高于对照组(P<0.05).     

Peak SIV replication in resting memory CD4+ T cells depletes gut lamina propria CD4+ T cells

In early simian immunodeficiency virus (SIV) and human immunodeficiency virus-1 (HIV-1) infections, gut-associated lymphatic tissue (GALT), the largest component of the lymphoid organ system, is a principal site of both virus production and depletion of primarily lamina propria memory CD4+ T cells; that is, CD4-expressing T cells that previously encountered antigens and microbes and homed to the lamina propria of GALT. Here, we show that peak virus production in gut tissues of SIV-infected rhesus macaques coincides with peak numbers of infected memory CD4+ T cells. Surprisingly, most of the initially infected memory cells were not, as expected, activated but were instead immunophenotypically 'resting' cells that, unlike truly resting cells, but like the first cells mainly infected at other mucosal sites and peripheral lymph nodes, are capable of supporting virus production. In addition to inducing immune activation and thereby providing activated CD4+ T-cell targets to sustain infection, virus production also triggered an immunopathologically limiting Fas-Fas-ligand-mediated apoptotic pathway in lamina propria CD4+ T cells, resulting in their preferential ablation. Thus, SIV exploits a large, resident population of resting memory CD4+ T cells in GALT to produce peak levels of virus that directly (through lytic infection) and indirectly (through apoptosis of infected and uninfected cells) deplete CD4+ T cells in the effector arm of GALT. The scale of this CD4+ T-cell depletion has adverse effects on the immune system of the host, underscoring the importance of developing countermeasures to SIV that are effective before infection of GALT.     

Host cell apoptosis induced by infection with duck swollen head hemorrhagic disease virus

This study aimed to examine the host cell apoptosis in the tissues of Peking ducks infected with duck swollen head hemorrhagic disease virus (DSHDV). The dynamic changes associated with apoptosis occurring in the internal tissues were evaluated at different time points postinoculation (PI) by performing hematoxylin and eosin (HE) staining, followed by light microscopy, terminal deoxynucleotidyl transfe- rase dUTP nick-end labeling (TUNEL) assay, and transmission electron microscopy (TEM). The results showed that DSHDV infection could induce apoptosis in host cells, including those of the bursa of Fabricius (BF), thymus, spleen, liver, intestinal tract, kidney, and esophagus. The apoptotic index (AI) values increased with time from 2 h to 72 h PI, and the highest values were recorded at 72 h PI. Further, cell death due to classic necrosis was observed in the dying or deceased ducks after 72 h PI. In conclusion, host cell apoptosis can be induced by DSHDV and may play an important role in the pathogenesis of duck viral swollen head hemorrhagic disease (DVSHD).     

人工合成非肽类Caspase-3抑制剂的研究进展

半胱氨酸蛋白酶（Caspase）家族是代表着一类细胞内的蛋白酶系统,在介导细胞凋亡扮演着重要的角色[1].细胞凋亡的发生是一个复杂Caspase家族引导的蛋白酶级联反应过程,尽管对于不同的细胞或不同信号传导途径诱发的凋亡过程中参与的Caspase有所不同,但Caspase-3是细胞凋亡蛋白酶级联反应的必经之路,也是凋亡的关键酶和执行者.而由Caspase调控的细胞凋亡的不正常激活是引起人体机能紊乱的一些疾病的主要根源,例如肿瘤、自身免疫性疾病、病毒性感染以及各种神经退行性疾病等.所以针对Caspases-3的抑制剂将可能是上述疾病的一种非常有效的治疗药物.由于天然的Caspase抑制剂和人工合成肽类Caspase抑制剂在特异性,透膜性,体内稳定性和活性等方面的不足,人们便开始了对人工合成非肽类抑制剂的研究.本文对近年来人工合成非肽类Caspase-3抑制剂的研究进展情况作一综述.     

Identification of Caspasecleavage site in the apoptosis suppressor protein P49 from the<Emphasis Type="Italic">Spodoptera littoralis</Emphasis> nucleopolyhedrovirus

The p49 gene from baculovirus Spodoptera littoralis nucleopolyhedrovirus (SINPV) was able to suppress apoptosis of 5~9 cells induced by virus infection. Ectopically expressed P49 protein had the capacity to inhibit the activity of Caspases, being the executioner of apoptosis. Digestion of P49 with human Caspase or Bm-Caspase both yielded 10 and 40 kD fragments. Checking the sequence of P49, we found that the motif 91-TVTDG-95 of P49 was the sequence recognized by Caspases. The mutant of P49, Asp94Ala, could not be cut by both caspases and lost its caspases inhibition.Meanwhile, Thr91Ala mutant permitted the cleavage and partially retained its activity of caspases inhibition. We also found that P49 was a substrate of upstream initiator caspase and downstream effector Caspases, indicating that P49 was a broad specificity Caspase inhibitor.     

Dynamic changes of apoptosis in duck embryo fibroblasts induced by new type Gosling viral enteritis virus

The monolayer duck embryo fibroblast (DEF) cells were experimentally infected with new type Gosling viral enteritis virus (NGVEV) and the dynamic changes of apoptosis were detected at different time points after NGVEV infection by using transmission electron microscopy (TEM), DNA agarose gel electrophoresis and Annexin V-FITC/PI stained fluorescence-activated cell sorter (FACS).The result shows that NGVEV can induce infected cells undergo apoptosis and change regularly. A series of characteristic apoptotic morphological changes including shrink of the cells, chromatin condensation and margination, as well as formation of apoptotic bodies were observed by TEM. The typical ladder pattern of DNA fragmentation was demonstrated by agarose gel electrophoresis. And using flow cytometry analysis of Annexin V-FITC/PI staining, the dead, viable, apoptotic and necrotic cells could be analysis quantitatively.     

Dynamic changes of apoptosis in duck embryo fibroblasts induced by new type Gosling viral enteritis virus

The monolayer duck embryo fibroblast （DEF） cells were experimentally infected with new type Gosling viral enteritis virus （NGVEV） and the dynamic changes of apoptosis were detected at different time points after NGVEV infection by transmission electron microscopy （TEM）, DNA agarose gel electrophoresis and Annexin V-FITC/PI stained fluorescence-activated cell sorter （FACS）. The result shows that NGVEV can induce infected cells undergoing apoptosis and changing regularly. A series of characteristic apoptotic morphological changes including shrinkage of the cells, chromatin condensation and margination, as well as formation of apoptotic bodies, were observed by TEM. The typical ladder pattern of DNA fragmentation was demonstrated by agarose gel electrophoresis. And using flow cytometry analysis of Annexin V-FITC/PI staining, the dead, viable, apoptotic and necrotic cells could be analyzed quantitatively.     

Infection Functions for Virus Propagation in Computer Networks: An Empirical Study

There has been an increasing amount of interest in modeling virus propagation in recent years. However, the group-based infection mechanism of computer viruses is not well understood and the selection of infection function in virus propagation modeling has not been well studied. This paper describes a point-to-group (P2G) infection mode to describe virus propagation in networks with information sharing groups. Simulations compare the constant infection and I-type infection functions with the new E-type infection function in the small-world-network environment. The simulation results show that the E-type infection function shows superior performances to that of the traditional I-type infection function in modeling the P2G virus infection mechanism and the I-type infection function shows better performance in modeling the random infection mechanism.