巨噬细胞移动抑制因子在大鼠急性坏死性胰腺炎模型中的作用研究

目的初步探讨巨噬细胞移动抑制因子（MIF）在大鼠急性坏死性胰腺炎（ANP）发病中的作用。方法健康雄性SD大鼠60只,随机分成三组,分别为对照组（腹腔注射生理盐水）、ANP组（腹腔注射左旋精氨酸）和干预组（腹腔注射左旋精氨酸＋单克隆抗MIF抗体）,每组20只。采用左旋精氨酸改良方法建立ANP模型,分别于3、6、12、24h四个不同时点处死5只大鼠,剖腹后从肠系膜上静脉取血,ELISA法测定血清MIF、TNF-α、IL-1、IL-6和IL-8水平 碘比法测定血淀粉酶 切取胰腺组织依据Kusske标准行胰腺病理学评分 Western blot法测定胰腺组织NF-κBp65蛋白的表达。结果ANP组血淀粉酶及胰腺组织病理学评分各时点㈦对照组相比均显著升高,干预组㈦ANP组相比均显著降低（P〈0.01） 胰腺组织NF-κBp65蛋白的表达于造模后3h开始呈持续性上调,与对照组相比其表达显著增多,在干预组其表达水平㈦ANP组相比明显下调（P〈0.01） 血清MIF、TNF-α、IL-1、IL-6各时点在ANP组与正常对照组相比其水平均有明显升高,在干预组其水平㈦ANP组相比显著降低（P〈0.05） 血清IL-8在6、12、24h不同时点水平变化同上述因子,但在3h时点其水平无明显升高 MIF、胰腺组织病理学评分及胰腺组织NF-κBp65蛋白的表达,两两之间均成正相关（P〈0.05）。结论腹腔注射左旋精氨酸建立ANP的模型是稳定的 MIF可能通过调控核因子NF-κB的途径影响血清TNF-α、IL-1、IL-6及IL-8水平而在大鼠急性胰腺炎发病过程中起一定的作用。     

脑神经元移行异常的MRI诊断

目的:报导38例脑神经元移行异常并总结本病MRI特点.材料和方法:38例小儿脑神经元移行异常患者.年龄3个月～14岁.主要临床表现为癫痫11例,智力减退17例,运动障碍16例.采用Toshiba 0.35T超导型MRI系统以自旋回波T1加权(T1WI)500/25ms及T2加权(T2WI)2000—4000/80ms,横断面及矢状面平扫,层厚5—10mm.结果:MRI特点:l)巨脑回/无脑回畸形20例.其中以无脑回为主者10例,表现额叶仅有几个扁平、粗大的脑回,顶枕叶脑表面光滑,无沟回显示.皮层增厚,白质变薄.以巨脑回为主者10例,主要表现脑回增宽,脑沟变浅.2)脑裂畸形16例.7例裂隙一端融合,9例裂隙分离.合并透明隔缺如者9例,合并多小脑回畸形者3例.3)灰质异位9例.孤立性2例,合并巨脑回/无脑回者3例,脑裂畸形者4例.结论:脑神经元移行异常MRI检查有典型征象,在本病诊断中起重要作用.     

丹参酮ⅡA、人参皂苷Rg_1和人参皂苷Rb_1配伍对平滑肌细胞的抑制作用

目的:探讨丹参酮ⅡA与复方丹参方中另两种有效成分人参皂苷Rg1和人参皂苷Rb1不同剂量配伍时对血管平滑肌细胞(VSMC)增殖、迁移的作用.方法:血管紧张素Ⅱ(AngⅡ)0.1 μmol/L诱导大鼠VSMC增殖,随后采用MTT法检测增殖细胞的活性、细胞划痕损伤实验检测细胞迁移数目、流式细胞术检测细胞周期的分布.结果:两味药配伍组中 Rg1 10 μmol/L Rb1 7 μmol/L、三味药配伍组中ⅡA 4 μmol/L Rg1 1 μmol/L Rb1 7 μmol/L抑制VSMC增殖的作用显著高于其他各组,且可以抑制细胞迁移,使细胞阻滞在G1期(P<0.01).结论:上述两种配伍可以明显抑制VSMC的增殖、迁移.     

Sema3A-Fc真核表达载体构建及诱导少突胶质细胞祖细胞迁移作用观察

目的 构建真核表达载体pIGSema3A-Fc,并观察Sema3A-Fc融合蛋白对少突胶质细胞祖细胞(OPCs)迁移的作用.方法 运用DNA重组技术自原核表达载体上将鸡来源的Sema3A基因克隆到真核表达载体pIGIsG1Fc上,并用双酶切、测序法进行鉴定.采用脂质体法转染非洲绿猴肾细胞株(COS-7)细胞进行融合蛋白表达,培养3天后提取上清液,经蛋白A亲和纯化,Western blotting进行鉴定.利用插入式细胞迁移小室(millicell-PCF)细胞迁移仓观察其对OPCs细胞迁移的诱导作用.结果 重组质粒双酶切产生了2.24kb目的 片段及5.7kb载体片段.测序证实构建的Sema3A膜外区与Sema3A-Fc cDNA阅读框完整,连接部位序列正确;Western blotting证实有Sema3A-Fc融合蛋白表达.迁移试验证明其对少突胶质细胞祖细胞迁移具有推斥作用.结论 成功构建了Sema3A-Fc真核表达载体,并使有生物学活性的Sema3A-Fc融合蛋白在COS-7细胞上获得了稳定表达,为进一步研究OPCs细胞定向迁移奠定了基础.     

辛伐他汀调控RhoA对血管平滑肌细胞增殖与迁移及纤溶活性的影响

目的:探讨不同浓度辛伐他汀调控小G蛋白RhoA及下游激酶ROCK信号对人主动脉血管平滑肌细胞(HAVSMCs)增殖和迁移,以及组织纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制剂-1(PAI-1)表达的影响及作用机制。方法:应用不同浓度Simvastatin(0.1μmol/L、1μmol/L、10μmol/L)处理HAVSMCs,CCK-8法和"划痕实验"分别检查细胞增殖和迁移能力,RT-qPCR检测RhoA mRNA及下游ROCK mRNA表达,应用RT-qPCR和ELISA检测纤溶活性相关t-PA/PAI-1mRNA及蛋白活性变化。结果:辛伐他汀呈浓度依赖性显著抑制HUASMCs的增殖和迁移能力。辛伐他汀能够显著抑制RhoA/ROCK信号途径,诱导PAI-1 mRNA表达下调从而抑制蛋白分泌表达,同时上调t-PA mRNA表达从而增加蛋白分泌表达,以10μmol/L辛伐他汀组处理24 h效果最为显著。结论:辛伐他汀呈浓度时间依赖性抑制RhoA/ROCK信号途径,并且上调t PA以及下调PAI-1基因转录及蛋白表达,从而促进纤溶,抑制细胞增殖和迁移。     

siRNA沉默YKL-40对支气管哮喘小鼠气道平滑肌增殖及迁移的影响

目的探讨小干扰核糖核酸（siRNA）沉默人软骨糖蛋白39（YKL-40）对支气管哮喘小鼠气道平滑肌增殖及迁移的影响。方法20 只健康雌性BALB/c 小鼠随机分为健康组（ n=10）和哮喘组（n =10）,采取腹腔注射抗原和雾化吸入卵蛋的方式复制哮喘模型,健康组小鼠处理与哮喘组相同,只是将致敏物换成生理盐水,留取气管和支气管进行细胞培养,两组小鼠气道壁平滑肌细胞根据转染物不同分为siRNA-YKL-40 组、阴性对照组和空白对照组,MTT法检测不同转染组小鼠气道壁平滑肌细胞增殖情况,Transwell 法检测不同转染组 小鼠气道壁平滑肌细胞迁移能力,实时荧光定量聚合酶链反应（qRT-PCR）和蛋白免疫印迹法（Western blot）检测不同转染组小鼠气道壁平滑肌细胞中YKL-40、白细胞介素4（IL-4）和干扰素-γ（IFN-γ）基因和蛋白表达。结果哮喘组中siRNA-YKL-40组48～96h时细胞吸光度A值均低于阴性对照组和空白对照组,哮喘组中siRNA-YKL-40 组、阴性对照组和空白对照组48～96 h 时细胞吸光度A 值均高于健康组,差异有统计学意义（p <0.05）;哮喘组中siRNA-YKL-40 组迁移细胞数（86.38±8.61）个,低于阴性对照组和空白对照组,哮喘组迁移细胞数均高于健康组,差异有统计学意义（p<0.05）;哮喘组和健康组中siRNA-YKL-40 组-40 基因和蛋白相对表达量均低于阴性对照组和空白对照组（ p<0.05）,哮喘组中siRNA-YKL-40 组-4 基因和蛋白相对表达量均低于阴性对照组和空白对照组,而-γ基因和蛋白相对表达量与IFN-γ/IL-4均高于阴性对照组和空白对照组（p <0.05）,与健康组比较,哮喘组中siRNA-YKL-40 组、阴性对照组和空白对照组-4 基因和蛋白相对表达量均升高,而- 基因和蛋白相对表达量和IFN-γ/IL-4均降低,差异有统计学意义（p <0.05）。结论靶向-40 基因沉默能抑制气道壁平滑肌细胞增殖及迁移,可能与调节IL-4/IFN-γ失衡状态而减少气道炎症反应有关。     

microRNA-18a Promotes Cell Migration and Invasion Through Inhibiting Dicer l Expression in Hepatocellular CarcinomaIn Vitro

Objective To investigate the effects of microRNA-18a (miR-18a) on migration and invasion of hepatocellular carcinoma (HCC) cells, and its possible mechanism associated with Dicer l. Methods HepG2 and HepG2.2.15 cells were transfected with miR-18a inhibitor using Lipofectamine. Cell invasion was evaluated by transwell invasion assay, and cell migration was detected by transwell migration and wound-healing assays. Moreover, luciferase reporter assay was used to identify whether Dicer expression was regulated by miR-18a. Real-time RT-PCR and western blot were performed to analyze Dicer 1 expression. In addition, a functional restoration assay was performed to investigate whether miR-18a promotes HCC cell migration and invasion by directly targeting Dicer 1. Results miR-18a inhibitor can suppress the migration and invasion of HCC cells. Furthermore, suppression of Dicer l expression by small interfering RNA essentially abolished the inhibition of cell migration and invasion induced by miR-18a inhibitor, restorating these activities to levels similar to the parental HCC cells. Interestingly, suppression of miR-18a in HCC cells resulted in enhanced expression of Dicer l. In addition, the results of a luciferase assay demonstrated targeted regulation of Dicer l by miR-18a. Conclusion Our findings suggest that miR-18a promotes migration and invasion of HCC cells by inhibiting Dicer l expression.     

The flavonoid quercetin induces apoptosis and inhibits migration through a MAPK-dependent mechanism in osteoblasts

The present study was undertaken to evaluate effects of quercetin, a major dietary flavonoid occurring in foods of plant origin, on cell viability and migration of osteoblastic cells. Quercetin inhibited cell viability, which was largely attributed to apoptosis, in a dose-and time-dependent manner in osteoblastic cells. Similar cytotoxicity of quercetin was observed in adipose tissue-derived stromal cells. Quercetin exerted a protective effect against H₂O₂-induced cell death, whereas it increased TNF-α-induced cell death. Western blot analysis showed that quercetin induced activation of ERK and p38, but not JNK. Quercetin-induced cell death was prevented by the ERK inhibitor PD98059, but not by inhibitors of p38 and JNK. Quercetin increased Bax expression and caused depolarization of mitochondrial membrane potential, which were inhibited by PD98059. Quercetin induced caspase-3 activation, and the quercetininduced cell death was prevented by caspase inhibitors. Quercetin inhibited cell migration, and its effect was prevented by inhibitors of ERK and p38. Taken together, these findings suggest that quercetin induces apoptosis through a mitochondria-dependent mechanism involving ERK activation and inhibits migration through activation of ERK and p38 pathways. Quercetin may exert both protective and deleterious effects in bone repair.     

Photodynamic therapy with photofrin reduces invasiveness of malignant human glioma cells

. In this study we investigated the influence of Photofrin-based photodynamic therapy (PDT) on the migration of two human glioma cell lines in vitro. U87 and U25ln tumour cells were treated with Photofrin at various doses and subjected to a fixed optical (632 nm) dose of 100 mJ/cm². Photofrin cytotoxicity was determined using MTT and colony forming assays. Using a matrigel artificial basement membrane migration assay, we demonstrated that low doses of subcytotoxic PDT treatment, such as PDT with 2.5 μg/ml Photofrin on U87 cells and 1 μg/ml on U25ln cells, significantly (p<0.001) inhibited in vitro migration of both cell lines. Furthermore, in a qualitative spheroid confrontation assay, subcytotoxic PDT of co-cultures between tumour spheroids and brain aggregates resulted in an absence of progressive tumour invasion and destruction of the brain aggregate. In conclusion, our data indicate that low-dose subcytotoxic PDT with Photofrin significantly inhibits invasiveness of U87 and U25ln cells. Paper received 8 May 2002; accepted after revision 19 June 2002. Correspondence to: Michael Chopp, PhD, Department of Neurology, Henry Ford Hospital, 2799 West Grand Boulevard, Detroit, MI 48202, USA. Tel: 313-916-3936; Fax: 313-916-1318; e-mail: chopp@neuro.hfh.edu     

Source–receptor probability of atmospheric long‐distance dispersal of viruses to Israel from the eastern Mediterranean area

Viruses that affect the health of humans and farm animals can spread over long distances via atmospheric mechanisms. The phenomenon of atmospheric long‐distance dispersal (LDD ) is associated with severe consequences because it may introduce pathogens into new areas. The introduction of new pathogens to Israel was attributed to LDD events numerous times. This provided the motivation for this study which is aimed to identify all the locations in the eastern Mediterranean that may serve as sources for pathogen incursion into Israel via LDD . This aim was achieved by calculating source–receptor relationship probability maps. These maps describe the probability that an infected vector or viral aerosol, once airborne, will have an atmospheric route that can transport it to a distant location. The resultant probability maps demonstrate a seasonal tendency in the probability of specific areas to serve as sources for pathogen LDD into Israel. Specifically, Cyprus’ season is the summer; southern Turkey and the Greek islands of Crete, Karpathos and Rhodes are associated with spring and summer; lower Egypt and Jordan may serve as sources all year round, except the summer months. The method used in this study can easily be implemented to any other geographic region. The importance of this study is the ability to provide a climatologically valid and accurate risk assessment tool to support long‐term decisions regarding preparatory actions for future outbreaks long before a specific outbreak occurs.