齐墩果酸诱导Kasumi-1细胞凋亡及对AML1-ETO表达的影响

目的 观察齐墩果酸(OA)诱导入急性髓系白血病M2型细胞株Kasumi-1凋亡及对AML1-ETO表达的影响.方法 用不同浓度OA作用于人急性髓系白血病M2型Kasumi-1细胞株,四氮唑蓝(MTT)法检测细胞增殖抑制率;Annexin V/PI双染色后,流式细胞仪检测细胞凋亡;Western blot法检测AML1-ETO蛋白表达水平;荧光原位杂交(Fish)检测融合基因AML1-ETO的变化.结果 OA以时间和剂量依赖方式抑制Kasumi-1细胞的增殖,24,48,72 h的IC50分别约为0.58,0.41,0.35 μmol·L-1.不同浓度(0.4,0.6,0.9μmol·L-1)OA作用24h后,细胞凋亡率明显增加,AML1-ETO蛋白表达下调.结论 OA对Kasumi-1细胞的抑制增殖和诱导凋亡作用可能与AML1-ETO的抑制有关.     

粘附分子ICAM—1、VCAM—1与类风湿性关节炎

类风湿性关节炎(Rheumatoid Arthritis，RA)是一种以慢性关节炎症主要表现的弥漫性结缔组织疾病。此病与免疫反应所致的损伤有关，病理特征为关节中淋巴细胞、巨噬细胞的浸润增多，滑膜被覆细胞层数和基质成分增多以及新血管翳形成，关节软骨破坏。近年来包括细胞间粘附分子(Inter Cellular Adhesion Molecule-1，ICAM—1)、血管细胞粘附分子     

胸腺肽α1辅助治疗甲型H1N1流感并肺炎的疗效

目的：观察胸腺肽α1对甲型H1N1流感并肺炎的临床疗效。方法：选取62例临床确诊为甲型H1N1流感并肺炎的患者,随机分为观察组、对照组各31例,两组均采用常规治疗,观察组在对照组基础上给予胸腺肽α1 1．6mg,隔日1次皮下注射,疗程2—4周。观察患者外周血常规、T细胞亚群的变化,同时观察临床症状、体温、胸片等进行疗效评价。结果：两组患者治疗前白细胞计数、淋巴细胞比例及CD3＋、CD4＋均低于正常值,中性粒细胞比例均高于正常值;治疗4—8d后,观察组淋巴细胞比例、CD3＋、CD4＋及CD4＋／CD8＋比值均高于对照组（P〈0．01）,白细胞计数先低到高再逐渐下降及中性粒细胞比例下降值低于对照组（P〈0．05）。结论：胸腺肽d,可提高甲型H1N1流感并肺炎患者的淋巴细胞比例及CD3＋、CD4＋及CD4＋／CD8＋比值,从而提高了机体T细胞免疫功能,有利于炎症控制,提高疗效。     

急性白血病患者中ICAM-1和VCAM-1的表达及意义

目的 探讨细胞间黏附分子1(ICAM-1)和血管细胞间黏附分子1(VCAM-1)在急性白血病(AL)中的表达及临床意义.方法 39例初诊AL患者,其中27例经治疗后达完全缓解(CR).采用逆转录-PCR法检测AL骨髓单个核细胞ICAM-1和VCAM-1的mRNA表达水平.对照组12例均为骨髓像正常的门诊患者.结果 ICAM-1和VCAM-1水平在初诊AL者明显高于CR组及对照组(P＜0.01),且CR组和对照组之间无显著差异(P＞0.05);高白细胞(WBC＞100×109/L)组和死亡组的ICAM-1和VCAM-1水平明显增高(P＜0.05).髓外浸润组仅ICAM-1高于非髓外浸润组(P＜0.01);非淋巴细胞AL(ANLL)具有良好核型者ICAM-1水平低于其他患者(P＜0.05).结论 AL表达ICAM-1和VCAM-1明显增高,其检测对疗效及预后判断有重要意义.     

PD-1/PD-L1表达水平与结直肠癌患者预后的研究进展

结直肠癌(CRC)是常见的消化系统肿瘤。近年来,CRC的治疗已经从外科治疗为主、放化疗为辅的综合治疗转向精准化、个体化治疗,应运而生的免疫治疗也越来越受到重视。程序性细胞凋亡蛋白1(PD-1)及其配体(PD-L1)的信号通路在肿瘤的免疫治疗中起着至关重要的作用。国内外有大量研究聚焦于各类实体肿瘤的PD-1/PD-L1免疫抑制信号通路,但是对于在CRC中这一信号通路的调控机制,尤其是对于PD-1/PD-L1表达水平与CRC患者的预后关系尚未明确,本文就PD-1/PD-L1表达水平与结直肠癌患者预后的相关研究作一综述。     

ICAM-1、VCAM-1在脑缺血损伤炎症机制中的作用及调控

细胞间黏附分子-1(ICAM-1)和血管细胞黏附分子-1(VCAM-1)在脑缺血损伤炎症过程中起着重要作用。脑缺血后ICAM-1和VCAM-1表达增加;ICAM-1、VCAM-1介导循环中的白细胞与内皮细胞黏附,进而浸润到血管外脑实质,导致缺血后炎症;抑制ICAM-1、VCAM-1表达及作用可减轻脑缺血损伤。     

硫酸右旋糖苷降低人胃癌MKN1细胞的黏附及整合素β1的表达

目的：探讨硫酸右旋糖苷(DS)对人胃癌MKN1细胞株的黏附抑制的机制。方法：用荧光免疫细胞染色法和共聚焦显微镜观察固定细胞和活细胞在培养盘上的附着过程及形态变化。用Western blotting法对整合素β1蛋白的表达进行分析。结果：MKN1细胞通过变形，形成伪足黏附到培养盘，并与其他细胞接触形成单细胞层。免疫染色可见整合素β1在细胞膜上有强表达，并且形成整合素集落。DS抑制了MKN1细胞的黏附，培养48h后仍有部分细胞处于游离状态。DS抑制整合素β1的表达并减少已经形成的整合素集落区域。使用DS后，黏附细胞整合素β1蛋白的表达分别减少到非治疗细胞的64％(130ku)和57％(110ku)，游离细胞整合素β1蛋白的表达分别减少到非治疗细胞的51％(130ku)和15％(110ku)。MKN1细胞同时还表现出维持圆形形状的倾向。结论：DS阻止人胃癌细胞株MKN1的黏附过程与抑制整合素β1的表达有关。     

CYP1A1对人血管内皮细胞内钙的影响

目的探讨CYP1A1对人血管内皮细胞HVEC304细胞内钙的影响,探索CYP1A1的内源性作用。方法构建CYP1A1的红色荧光表达载体,转染人血管内皮细胞,激光共聚焦检测细胞内的钙离子浓度。结果CYP1A1表达载体在人血管内皮细胞中成功表达,定位于细胞质。过表达CYP1A1的HVEC304细胞(HVEC304-CYP1A1)中游离钙的浓度明显低于未转染的HVEC304细胞(P<0.01)。随着veratridine浓度的上升,HVEC304-CYP1A1细胞中游离钙的水平逐渐上升。结论过表达CYP1A1人血管内皮细胞中,钙离子基础水平明显降低,veratridine可以剂量依赖性地逆转这一作用。     

APE1/Ref-1、EGR-1在食管鳞癌中的表达及相关性研究

目的 本研究旨在明确APE1/Ref-1和EGR-1在食管鳞癌及癌旁组织中的表达情况,并结合临床资料评估其表达与组织分级和临床分期之间的关系,为进一步研究食管鳞癌的发生发展机制提供参考依据,并为食管鳞癌的预防、诊治提供临床指标.方法 随机选取2009至2010年接受胸外科手术治疗的86例食管癌标本,术前均未经放化疗等任何抗癌治疗.采用免疫组织化学法(S-P法)测定APE1/Ref-1的蛋白、EGR-1的蛋白表达情况,对其相关性进行分析.结果 APE1/Ref-1在ESCC组织中细胞质和细胞核联合阳性表达率为68.6%明显高于癌旁组织的联合阳性表达率8.1%,差异有统计学意义(P<0.01).APE1/Ref-1在癌旁组织中的细胞核阳性表达率为91.9%明显高于ESCC组织的24.4%,差异有统计学意义(P<0.01).EGR-1在ESCC组织的阳性表达率显著低于癌旁组织(P<0.01).结论 在ESCC中,APE1/Ref-1胞核胞质联合表达率随着组织学分级降低和临床分期的升高有增强的趋势,EGR-1的阳性表达率随着组织学分级降低和临床分期的升高有降低的趋势.     

Cryopreservation of plant cell cultures1

The main topics of this brief overview of the cryopreservation of plant cell cultures are (a) the principles behind Cryopreservation procedures as a basis from which the appropriate method for various different cultures can be developed, and (b) the question of how far the characteristics of cell strains are preserved during the freeze-thaw cycle. Of all the species successfully cryopreserved to date, only seven have been investigated with regard to their biochemical capacities. In all these cases the cultures have been shown to retain their growth patterns and biochemical traits. Furthermore, results are available which indicate that this is also valid for long-term storage. Some details are presented on the accumulation of natural products and the biotransformation of cardenolides in frozen-thawed cell cultures. On the other hand, before it is possible to recommend universally applicable cryopreservation protocols, we must better understand the cellular events which determine the freeze-tolerance of plant cell cultures.     

Single cell analysis of switch-like induction of CYP1A1 in liver cell lines.

The shape of the dose-response curve may vary depending on whether one examines response at a population or a single cell level. Populations of cells may exhibit a graded response whereas single cell responses may have threshold or switch-like behavior. Studies in vivo and in vitro using primary hepatocyte cultures have shown that induction of CYP1A1 in the liver exhibits switch-like behavior in response to PCB 126 (3,3',4,4',5-pentachlorobiphenyl). The goal of the present study was to determine if two liver cell lines (H4IIE rat hepatoma and Hepa 1c1c7 mouse hepatoma) also show switch-like behavior and develop experimental models for studying mechanisms of these switch-like responses. Both cell lines were analyzed via concentration-response and time-course studies using quantitative real-time PCR, revealing a sigmoidal concentration-response curve for CYP1A1 mRNA induction at the population level. To study CYP1A1 protein induction on a single cell level, flow cytometry was employed. In both cell lines the distribution of fluorescence increased with increasing concentrations of PCB 126. The switch behavior was more pronounced in the H4IIE cells than in the Hepa 1c1c7 cells, exhibiting a well-defined shift of induction from the "off" to the "on" state. The concentration-response curve at the single cell level appeared more switch-like with two populations of cells-basal levels and maximally induced. Immunocytochemistry studies of individual cells also support these conclusions. Our data support the hypothesis that PCB 126 induces CYP1A1 in a switch-like fashion in H4IIE rat hepatoma cells. These cells can now be used to study the mechanism of the biological switch.     

X线修复交叉互补基因1缺陷细胞株的建立及其蛋白的表达

目的 运用载体介导的RNA干扰技术靶向抑制人X线修复交叉互补基因1(XRCC1)在支气管上皮细胞中的表达,为研究人XRCC1蛋白在环境化学污染物所致DNA损伤修复中的功能和机制作准备.方法 利用分子克隆技术构建含pU6启动子的XRCC1 RNA干扰特异性绿色荧光蛋白C1载体重组子"pEGFP-C1-U6-dsRNA";以脂质体法将载体重组子转染人支气管上皮细胞,同时以空白细胞和空载体转染细胞作对照;在经G418筛选后,以荧光显微成像技术观察细胞的转染效果,以蛋白印迹法分析转染后细胞中的XRCC1蛋白表达情况.结果 在转染重组子的细胞中,XRCC1蛋白的表达明显下调,仅相当于正常细胞的38.2%.结论 人支气管上皮细胞人X线修复交叉互补基因1的靶向抑制成功.     

The role of CDK1 siRNA interference in cell cycle and cell apoptosis

In the present report, cyclin-dependent kinase1 (CDK1) siRNA was transfected into cells to silence the CDK1 gene expression and study its role in the cell cycle and cell apoptosis. The siRNA targeting CDK1 gene was chemically synthesized and transfected into Hela cells by lipofectamine 2000. The expression levels of CDK1 gene and protein were examined by real-time quantitative polymerase chain reaction (PCR) and Western blot, respectively. The cell cycle was analyzed by using DNA content analysis by flow cytometry. Cell apoptosis was detected by the Annexin V/PI method. The morphological changes of transfected cells were examined under the microscopy by Wright-Giemsa stain. CDK1 gene was successfully silenced by its siRNA, and the CDK1 protein expression level was decreased significantly, especially from 48th h to 60th h after transfection. The DNA content analysis showed that transfection of CDK1 siRNA led to cells accumulating in G₂/M phase. There was no significant difference in the apoptotic rate between transfected cells and the control cells after transfection of CDK1 siRNA for 48 or 60 h. More double nucleus or multinucleus cells could be seen under the microscopy among the transfected cells. The decreased CDK1 expression by siRNA silencing gave rise to cell cycle arrest in G₂/M phase but did not induce apoptosis.     

窖蛋白1在无血清状态下诱导FBJ细胞死亡

目的研究无血清状态下,FBJ-S1细胞较FBJ-LL细胞更易死亡的原因。方法用细胞活性检测法分析细胞的活性,分别用HPTLC法、逆转录PCR法和免疫印迹法检测细胞中GD1a和窖蛋白1(caveolin-1)的含量。结果研究表明,在无血清培养基培养条件下,富含神经节苷脂GM3和GD1a的低转移性的FBJ-S1小鼠骨肉瘤细胞趋向死亡,但对含有几乎相同量GM3而无GD1a表达的高转移性的FBJ-LL细胞的生长却未见明显影响。同时发现:a.FBJ-S1细胞富含窖蛋白1,而FBJ-LL细胞中窖蛋白1表达量则较低;b.利用小干扰基因沉默技术在FBJ-S1细胞中沉默窖蛋白1的表达,结果使细胞存活率升高;c.使用GD1a处理FBJ-LL细胞导致其趋向死亡,通过免疫印迹法检测窖蛋白1发现其蛋白表达量增加。结论在无血清培养条件下,窖蛋白1诱导FBJ细胞的死亡。     

Influence of natural and synthetic compounds on cell surface expression of cell adhesion molecules, ICAM-1 and VCAM-1

Various natural and synthetic compounds including alkaloids, terpenoids and phenolics were tested for inhibition of the cell surface expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), both of which are crucial in the regulation of immune response and inflammation. Of 40 compounds tested, two compounds significantly downregulated the expression of VCAM-1 on murine endothelial cells (F-2) and ten compounds that of ICAM-1 on mouse myeloid leukemia cells (M1). Sanguinarine chloride (5) and isoliquiritigenin (13) were capable of lowering the levels of both ICAM-1 and VCAM-1. The structure-activity relationships study on chalcone and flavone derivatives related to 13 suggested that the inhibitory activity of the chalcone derivatives is attributable to the 4-hydroxy group as well as the possible coplanarity between the phenyl ring and the adjacent conjugated ketone.     

Biotransformation of cardenolides by plant cell cultures1

A culture of DAUCUS CAROTA cell line Ca68, previously shown to specifically hydroxylate digitoxigenin at the C-5 position, has been shown also to convert gitoxigenin and oleandrigenin to their corresponding 5beta-hydroxy derivatives. These two products have not been identified previously. 5beta-Hydroxygitoxigenin has been identified by physico-chemical methods and data on its mass spectrum and (13)C-NMR spectrum are reported. 5beta-Hydroxyoleandrigenin was identified from its high resolution mass spectrum. Addition of gitoxigenin at 72 hrs after inoculation resulted in a two fold increase in the rate of bioconversion compared to addition at 0 hr. The results are discussed in relation to other biotransformation reactions and with respect to improving the yields of plant products and the formation of novel compounds.     

Neurotoxicity of 1-methoxycycloheptatriene--a Purkinje cell toxicant.

The toxicity of 1-methoxycycloheptatriene (1-MCHT), a sensory irritant, has been investigated in beagles. It was found to produce gross inco-ordination of the limbs at intravenous doses greater than 10 mg kg-1. The main histological abnormalities were in the cerebellum and consisted of Purkinje cell death and subsequent reactive gliosis. A few necrotic neurons were seen in the diencephalon, pons and medulla. Haematological abnormalities, e.g. leucocytosis with relative lymphopenia, were seen, while biochemical changes included hyperglycaemia and a rise in plasma aminotransferases. The no-effect dose for the histological and biochemical changes was the same. These abnormalities are compared with cerebellar changes observed in acrylamide and other toxic states.     

SIRT1与成体干细胞衰老

成体干细胞(adult stem cells)具有自我更新功能并可以分化为执行特定功能的体细胞,维持组织和器官结构完整和功能健全。有研究显示衰老可以出现在成体干细胞水平,并与机体老龄化及损伤修复能力下降有关。哺乳动物沉默调节因子2相关酶1(Sirtuins 1,SIRT1)是NAD+依赖性蛋白去乙酰化酶。对体细胞的研究表明,提高SIRT1活性可以抗细胞衰老。近年来,成体干细胞的相关研究表明SIRT1可能具有平衡干细胞的静息与增殖、维持干细胞自我更新功能、缓解年龄相关性成体干细胞功能下降和抑制成体干细胞分化紊乱的作用,但其抗衰老的分子机制还有待进一步研究。