Production and interaction of oxygen and nitric oxide free radicals in PMA stimulated macrophages during the respiratory burst

The activity of nitric oxide synthase (NOS) during the respiratory burst in phorbol-1,2-myristate-1,3-acetate (PMA) stimulated macrophages has been the topic of much debate in the literature. To help clarify the role of NOS, we have examined the chemiluminescence arising from peroxynitrite production, nitrite/nitrate and nitric oxide production, and oxygen consumption during the respiratory burst in PMA-stimulated macrophages. The Griess reaction was used to measure nitrite/nitrate, spin trapping with N-methyl D-glucamine dithiocarbamate (MGD)2-Fe2+ was used to quantify nitric oxide, and the spin probe 2,2,6,6-tetramethylpiperidine-N-oxyl-4-ol (TEMPOL) was used to measure oxygen consumption. Oxygen free radical production (hydroxyl and superoxide free radicals) was also investigated using the spin trap 5,5-dimethyl-1-pyroline-1-oxide (DMPO). The chemiluminescence emitted by the PMA-stimulated macrophages and nitrite/nitrate in the culture system were both found to increase. However, the rate of nitric oxide release remained constant, indicating that the activity of NOS is not enhanced during the respiratory burst in PMA stimulated macrophages.     

人MCP cDNA在NIH3T3细胞中表达及功能研究

通过构建表达人膜辅因子蛋白ＭＣＰ编码区全长ｃＤＮＡ的重级载体ｐｃＤＮＡ３ＭＣＰ,以磷酸钙沉淀法转染ＮＩＨ３Ｔ３细胞,用Ｇ４１８筛选阳性克隆,并鉴定ＭＣＰ ｃＤＮＡ在细胞中的表达。将血清梯度稀释并与细胞孵育,然后检测细胞活力：灭活的人血清不能引起对照细胞与ＭＣＰ转染细胞的胞毒作用,而新鲜人血清可使对照细胞发生补体依赖的细胞毒反应,ＭＣＰ转染细胞由于ＭＣＰ蛋白的合成,细胞受到保护不发生该反应。另外,Ｍ     

酪酸梭菌--婴儿型双歧杆菌二联活菌制剂对人体肠道菌群的调节试验

目的　观察酪酸梭菌——婴儿型双歧杆菌二联活菌制剂对受试人群肠道菌群的影响。方法　检测受试者服用前后的肠道菌群并计数。结果　肠杆菌、肠球菌、拟杆菌的数量无明显变化 ,双歧杆菌、乳杆菌的数量明显增加 ,差异有非常显著性 (P<0 .0 1) ,结论　酪酸梭菌——婴儿型双歧杆菌二联活菌制剂具有一定的调节人体肠道菌群、增殖双歧杆菌和乳杆菌的作用。     

不同DNA疫苗联合接种可有效增强免疫效果

造反乙型肝炎（乙肝）病毒核心抗原（ＨＢｃＡｇＡ）、ｅ抗原（ＨＢｅＡｇ）及单纯疱疹病毒ｇＤ抗原（ＨＳＶ－１－ｇＤ）基因为目的基因,进行ＤＮＡ疫苗联合免疫的研究。通过对不同基因片段的表达研究,选择了能在哺乳动物细胞中高效表达乙肝病毒核心抗原、ｅ抗原和单纯疱疹病毒ｇＤ抗原的质粒ＤＮＡ免疫Ｂａｌｂ／ｃ小鼠。结果显示：表达乙肝病毒核心抗原和单纯疱毒ｇＤ抗原的ＤＨＡ疫苗单独免疫,能有效刺激机体产生体液免疫和细     

B→O血型转变工具酶α-半乳糖苷酶cDNA克隆及表达

 α-半乳糖苷酶是实现 B→O血型转变、制备通用型血的关键工具酶 .利用反转录 PCR方法从中国海南 Catimor咖啡豆中克隆α-半乳糖苷酶 c DNA,插入嗜甲基酵母 P.pastoris分泌表达载体 p PIC9K中 ,转化 P.pastoris GS1 1 5,筛选高表达重组菌株 .经甲醇诱导表达 7d后 ,发酵液总蛋白分泌量约 1 .2 mg/ml,SDS- PAGE呈现约 41 k D特异表达带 ,与专一性底物对 -硝基 -苯基 -α- D-吡喃半乳糖苷反应证明 ,表达产物具有 α-半乳糖苷酶活性 ,最高达到 1 8U/ml.初步实验表明 ,表达的 α-半乳糖苷酶可酶解 B型红细胞 ,成功实现 B→O血型转变 .     

Cytoplasmic localization of the interferon-inducible protein that is encoded by the AIM2 (absent in melanoma) gene from the 200-gene family

While interferons (IFNs) (alpha, beta and gamma), a family of cytokines, have the ability to exert the growth-inhibitory effect on target cells, the molecular mechanism(s) by which IFNs inhibit cell growth remains to be identified. Because IFN-inducible 'effector' proteins mediate the biological activities of IFNs, characterization of IFN-inducible proteins is critical to identify their functional role in IFN action. One family (the 200-family) of IFN-inducible proteins is encoded by structurally related murine (Ifi202a, Ifi202b, Ifi203, Ifi204 and D3) and human (IFI16, MNDA and AIM2) genes. The proteins encoded by genes in the family share a unique repeat of 200-amino acids and are primarily nuclear. The AIM2 gene is a newly identified gene that is not expressed in a human melanoma cell line. Here we report that AIM2 is estimated to be a 39 kDa protein and, unlike other proteins in the family, is localized primarily in the cytoplasm. Interestingly, overexpression of AIM2 in transfected cells retards proliferation and, under reduced serum conditions, increases the susceptibility to cell death. Moreover, AIM2 can heterodimerize with p202 in vitro. Together, these observations provide support to the idea that AIM2 may be an important mediator of IFN action.     

转基因猪外源基因染色体定位的研究

转基因猪外源基因染色体定位的研究ＥＸＯＧＥＮＯＵＳＧＥＮＥＬＯＣＡＬＩＺＡＴＩＯＮＯＮＣＨＲＯＭＯＳＯＭＥＳＯＦＴＲＡＮＳＧＥＮＩＣＰＩＧ关键词基因定位染色体原位杂交转基因猪ＫｅｙｗｏｒｄｓＧｅｎｅＬｏｃａｌｉｚａｔｉｏｎ,Ｉｎｓｉｔｕｈｙｂｒｉｄ...