Radiotherapy suppressed tumor-specific recruitment of regulator T cells via up-regulating microR-545 in Lewis lung carcinoma cells

Objective: Radiotherapy is an important treatment for cancer. The main irradiated action is thought to be the irreversible damage to tumor cell DNA, but recent studies showed that high dose radiotherapy related to the tumor immune response. This study was designed to determine the relationship between Lewis lung tumor radiosensitivity and CD4+CD25+ regulatory T cells (Tregs) infiltration and elucidate the underlying mechanisms in vitro. Methods: With tumor transplantation method to establish mice Lewis lung tumor mice model, to observe the inhibition rate of radiotherapy to tumor growth. Proliferation profiles of CD4+CD25+ Tregs and CD4+ T cells were assessed by flow cytometry. MiR-545 and CCL-22 mRNA were determined by Quantitative Real-Time PCR. CCL-22 protein was determined by western blot assay. Results: Radiotherapy caused a time-dependent inhibition of tumor growth as well as a decrease in the percentage of tumor-infiltrating CD4+CD25+ Tregs of CD4+ T cells compared with no treatment group. And the miR-545 was significantly upregulated and CCL-22 was significantly down-regulated in irradiated tumor and Lewis lung cancer cells. In Lewis lung cancer cell transfection experiments, mimic or inhibitor for miR-545 negatively regulated CCL-22 expression when cells treated or treated without irradiation. Silenced miR-545 promotes CD4+CD25+ Treg proliferation. Additionally, silenced miR-545 reversed radiosensitivity of Lewis lung cancer. Conclusion: Radiotherapy suppressed specific recruitment of regulator CD4+CD25+ Treg cells in Lewis lung carcinoma via up-regulating microR-545.     

间断静脉滴注3%高渗盐水与20%甘露醇治疗小儿急性脑水肿的疗效对比

Objective To compare the clinical efficacy of 3% hypertonic saline with 20% mannitol in the treatment of acute brain edema in children.Methods Twenty children with acute brain edema were randomly divided into hypertonic saline(HS) group and mannitol group.HS group and mannitol group were given 3% HS solution or 20% mannitol respectively.Main outcome measurements included intracranial pressure(ICP),mean arterial pressure(MAP),central venous pressure(CVP),cerebral perfusion pressure (CPP),serum electrolytes,plasma osmolality,renal function and urine volume.Results Both 3% HS and 20% mannitol were effective in reducing ICP(P ＜0.05).Therapeutic effect lasted(4.5±1.2) h in HS group and(3.2±1.5) h in mannitoi group.3% HS had a longer duration of action than marmitol(P＜0.05).At the time point of 2 hours after treatment,MAP and CPP of HS group increased more than those of mannitol group(P＜0.05).Conclusion Both 3% HS and 20% mannitol could rapidly decrease ICP.3% HS has a longer duration of action in reducing ICP than 20% mannitol.3% HS is more effective in stabilizing circulation and improving CPP than 20% mannitol.     

新生儿B组链球菌感染传播途径的研究

目的 确定新生儿Ｂ组链球菌（ＧＢＳ）感染的传播途径和随机引物扩增多态性（ＲＡＰＤ）分型方法的应用价值。方法 采用血清学、核酸杂交和ＰＡＲＤ方法对２例诊断为早发型ＧＢＳ肺炎和晚发型ＧＢＳ脑膜炎患儿体内分离的５株ＧＢＳ和其母阴道分离的２株ＧＢＳ菌株作母婴配对分析,对８８株孕妇生殖道携带ＧＢＳ进行ＲＡＰＤ分型研究。结果 １例早发型ＧＢＳ肺炎母婴配对ＧＢＳ血清型均为ＩＩＬ／Ｒ型致病,毒力因子基因片段大小」     

胎粪吸入幼兔外周血及支气管肺泡灌洗液中肿瘤坏死因子-α的表达

目的 探讨TNF-α在胎粪吸入幼兔肺部炎症反应中的表达水平及意义.方法 将20只日龄21～30 d幼兔随机分为模型组和对照组,每组10只.模型组经气管导管注入胎粪悬混液,复制胎粪吸入性肺炎模型;对照组手术操作与模型组相同,但无胎粪悬液注入,不复制模型.酶联免疫吸附法检测2组幼兔外周血和支气管肺泡灌洗液TNF-α表达水平,并行统计学分析.结果 模型组幼兔肺组织出现Ⅰ型肺泡上皮细胞变性,Ⅱ型肺泡内板层小体呈空泡样改变等炎性损伤表现,且外周血和支气管肺泡灌洗液中TNF-α表达水平均高于对照组(Pa<0.05).结论 TNF-α参与介导了胎粪吸入后肺部的炎症反应.     

森林脑炎病毒prM-E蛋白在昆虫细胞中的表达及免疫活性测定

目的为了表达森林脑炎病毒prME蛋白,为森林脑炎快速诊断试剂的研制奠定基础。方法经过RTPCR扩增、重组转移载体构建、细菌内转座和昆虫细胞转染,以杆状病毒昆虫细胞表达系统成功地表达了森林脑炎病毒MDJ01株prME蛋白。结果从感染细胞上清中电镜观察到重组蛋白形成的球型颗粒,说明重组病毒感染细胞后产生病毒样表达颗粒(viruslikeparticlesVLPs),并且分泌至细胞外。免疫印迹试验和间接免疫荧光试验表明,表达的重组蛋白能够与抗森林脑炎病毒抗体特异结合,具有良好的抗原性。ELISA和间接免疫荧光染色证实,重组prME蛋白可以作为抗原用于检测患者血清特异性抗体。结论在昆虫细胞中表达的prME具有良好的抗原性,本研究为森林脑炎快速特异诊断试剂研制奠定了基础。     

冠状动脉血管直径测量方法的研究

心脏是人体生命活动的重要器官，能否正常工作主要是由心血管系和心传导系决定。冠状动脉是给心脏供血的唯一途径，心肌能否得到足够的营养、保持连续有节奏地运动，完全取决于冠状动脉是否能不断地供给其营养。冠状动脉直径的测量以及血管直径参数对于反映心脏功能和疾病的诊断具有重要意义。文中提出一种新型的、简便的血管直径测量方法，利用计算得到的血管直径，我们就可以判别心血管狭窄位置。     

外源性五羟色胺大鼠肺出血模型及其与浓度关系

目的　通过外源性五羟色胺 (5 -HT)气管滴入建立新生大鼠肺出血模型及其与浓度关系 .方法　模型制作 :日龄 4～ 5天Wistar二级大鼠 5 0只 ,随机分为 4组 :生理盐水对照组 (A组 )及 3种不同浓度外源性 5 -HT实验组(B、C、D组 ) :经气管导管分别滴入生理盐水和不同浓度 5 -HT ,4小时后处死 ,观察肺大体及组织病理改变 ,将肺出血程度分为 5级 :Ⅰ正常 ;Ⅱ肺水肿 ;Ⅲ点状肺出血 ;Ⅳ局灶性肺出血 ;Ⅴ弥漫性肺出血 ,选择出制作肺出血模型的最佳的浓度 .结果　不同浓度 5 -HT气管内滴入均能引起不同程度肺出血 ,但随着浓度增加 ,B、C、D三组间的肺出血程度无差异 (p >0 .0 5 ) ,其中D组死亡率 30 % ,对照组及B组和C组均无死亡 ,死亡鼠肺为弥漫性出血 .结论　 5 -HT可致大鼠肺出血 ,以 1× 10 -5mol/ml浓度为宜 ,随着 5 -HT浓度增加 ,大鼠死亡率增加 ,但肺出血发生率无差异     

抚触对人工喂养新生儿生长发育的影响

目的 探讨抚触对人工喂养儿生长发育影响。方法 选择30例人工喂养新生儿进行抚触,并随机选择条件相似的30例人工喂养儿做对照,100d时比较两组婴儿的身长、头围、体质量、日摄奶量、睡眠时间、大便情况。结果 抚触组人工喂养婴儿的体质量、摄奶量较对照明显增加,睡眠时间较对照组长,且较对照组大便正常,较少发生便秘。身高、头围无明显差异。结论 抚触能明显提高人工喂养儿的体质量及摄奶量,促进排泄,改善睡眠。     

我国HIV-1 B''亚型毒株gag基因变异特征研究

目的研究我国人免疫缺陷病毒1型（HIV-1）B’亚型主要流行株在宿主免疫压力下的基因变异及抗原表位的变化特征，探讨选择压力、基因离散率和抗原表位变化之间的关系。方法从确诊的HIV-1感染者的全血样本中提取基因组DNA，经套式聚合酶链反应（PCR）扩增后，将扩增产物进行纯化和测序。然后将所得序列进行系统进化树和氨基酸变异分析，使用GCG软件包的Distance程序对P17和P24两个区段计算基因距离，用Diverge程序计算同义替换（1（s）和非同义替换（1（a）及二者之间的比值，并对我国人群中较常见的HLA型别限制的CTL表位的突变情况进行分析。结果HIV-1B’亚型毒株的P17区段的Ks／Ka值〈1，而P24区段的Ks／Ka值〉1；P24部分的基因离散率低于P17部分；P17区段抗原表位的保守率为34．94％，而P24区段抗原表位的保守率为67．38％；从基因离散率、所受的选择压力及抗原表位的突变率3个方面来看，HIV-1的P17区段均明显大于P24区段。结论HIV-1B’亚型毒株的P17区段的抗原表位变化较大，而P24区段的抗原表位相对较为保守。提示P24区段的CTL表位更适合于表位疫苗的研制。