二氧化硅活化巨噬细胞中早期生长反应因子-1及其信号转导通路的研究

目的 探讨早期生长反应因子(Egr-1)及其信号转导在矽肺发生发展中的作用。方法用细胞免疫荧光、原位杂交方法检测二氧化硅(SiO2)刺激后Egr-1的表达定位,用报道质粒及EMSA检测其活性改变;用激酶活性分析法检测si0：刺激巨噬细胞后ERK1／2活性改变,进一步用激酶抑制剂初步探讨SiO2活化Egr-1的信号转导通路。结果SiO2刺激RAW264．7细胞短时间Egr-1核蛋白表达及转录因子明显增加;且在处理后30～60min,Egr-1核蛋白结合活性明显升高(为未处理组的20倍);在刺激后15min ERK1／2活性开始升高,30min达高峰(活性为对照组的29倍)而后渐降至基础水平;进一步用激酶阻断发现,Egr-1 mRNA及蛋白表达均减少。结论SiO2能激活巨噬细胞中Egr-1,且此过程可能由ERK1／2、p38介导,提示SiO2-ERK1／2、p38-Egr-1通路可能在矽肺发生发展过程中起重要作用。     

Concomitant translocation of Puralpha with its binding proteins (PurBPs) from nuclei to cytoplasm during neuronal development

Two Puralpha-binding proteins (PurBPs) were found in nuclear extract from mouse brain during P4-P10 by the overlay assay. At P14, they were decreased significantly in nuclear extract and increased in the S3 fraction, indicating their dynamic translocation during development. Western blot analysis also demonstrated concomitant translocation of Puralpha with the PurBPs during P7-P14, when neuronal circuit proceeds. Immunocytochemical study with cultured hippocampal neurons from rat E18 confirmed that nuclear Puralpha was translocated to cytoplasm after plating for 7-14 days. These results suggest that spatiotemporal translocation of Puralpha with the PurBPs from nuclei to cytoplasm has a crucial role in neuronal development.     

脑血流断层显像Bullseye显示

为了探讨用Bullseye显示脑血流灌注显像数据的可能性,对8例典型脑梗塞病例及15例脑血流断层显像常规分析可疑病例的脑血流断层显像的横断面数据进行Bullscye显示,结果8例典型病人病灶用普通Bullseye即显示良好;常规分析可疑病例病变用普通Bullseye 8例显示良好,变黑Bullseye 13例显示出病灶;结果提示利用Bullseye显示脑血流灌注显像数据的可能。     

一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征

合成了一系列分子量较低的聚乙二醇．聚己内酯-聚乙二醇（Poly（ethylene glycol）-Polycaprolactone-Poly（ethylene glycol），PEG-PCL—PEG）三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性，当水溶液浓度高于临界凝胶浓度（Critical gel concentration，CGC）时，随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度，以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件，可以在一定程度上拓宽凝胶-溶胶转变温度范围，有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。     

小鼠甲胎蛋白与结核杆菌热休克蛋白70基因融合载体的构建及体外表达

目的 构建小鼠甲胎蛋白(α-Fetoprotein，AFP)与结核杆菌热休克蛋白70(Mycobacterium tuberculosis heat shock protein 70，Mt．HSP70)基因融合载体．并研究其在真核细胞中的表达情况。方法 以pcDNA3.1为基本单位构建AFP及HSP70的融合表达载体，融合基因以G-S-G-G-S连接子连接；用脂质体将系列载体导入COS-7细胞．48h后以免疫化学方法检测其表达。结果 构建的AFP和HSP70的单独及融合表达载体导入COS-7细胞48h后经RT-PCR检测可扩增出相应片段，细胞免疫化学染色为阳性。结论 AFP和HSP70的单独及融合表达载体构建成功，并能在真核细胞中表达。     

Translocation of Enterococcus faecalis strains across a monolayer of polarized human enterocyte-like T84 cells

We used a two-chamber system to study transcytosis of Enterococcus faecalis across monolayers of human colon carcinoma-derived T84 cells, which show structural resemblance to the native intestine. Among 16 E. faecalis isolates from different sources, the well-characterized strain OG1RF and 8 other isolates (2 endocarditis isolates, 1 urine isolate, and all 5 fecal isolates) showed translocation in this assay, while 6 clinical isolates (3 endocarditis and 3 urine isolates), the recipient strain JH2-2, and the control, Escherichia coli DH5alpha, had no detectable translocation. Of two OG1RF mutants involving the previously studied epa (enterococcal polysaccharide antigen) gene cluster, known to be needed for virulence and resistance to killing by polymorphonuclear leukocytes, one epa mutant (TX5179) was unable to translocate, while TX5180, with an epa disruption farther downstream, showed a moderate decrease in translocation relative to that of the wild-type strain OG1RF (P < 0.01), indicating that the epa gene cluster is important for translocation across a T84 monolayer. This observation was confirmed by complementation of the epa mutant (TX5179) with epa genes and restoration of its translocation ability. In conclusion, we have demonstrated translocation of at least some strains of E. faecalis across T84 monolayers, although strains differ considerably in this ability, and we have demonstrated that epa mutations can cause marked changes in successful translocation. These results suggest that this model may be a useful in vitro system for studying the process of translocation from the intestinal tract.     

Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation

To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo.     

掌指关节的三维解剖及形态分析

目的：观测掌指关节关节面的几何形态,为人工关节的设计和应用提供解剖学依据。方法：10只成人手标本,解剖掌指关节,测量侧副韧带起点距掌骨头关节面的直线距离,三维数据检测仪获得关节面三维坐标数据,应用SPSS软件进行统计分析和成像。结果：掌骨头有双髁结构,桡侧髁略大,第1掌骨头形态特殊;各掌骨头高度的比较无显著差异;其掌侧关节面大于背侧,第2、3掌骨头关节面面积明显较大。近节指骨底在形态、高度和面积方面各序列相似;各序列侧副韧带起点桡侧较尺侧距离掌骨头关节面远。结论：手指人工关节的设计应符合解剖形态,并根据各序列形态的差异进行个体化设计,尤其拇指更应区别对待;手指人工关节的设计和应用中应注意软组织保护,关节的切除范围应注意保留侧副韧带的起止点。