Inhibitory effect of berberine on the activation and proliferation of T lymphocytes

AIM: To investigate the effect of berberine (Ber) on the activation and proliferation of T lymphocytes and its mechanism of action. METHODS: Whole peripheral blood from normal subjects was stimulated with phytohemagglutinin (PHA) or phorbol ester (PDB) plus ionomycin (Ion) and the expression levels of CD69 and CD25 were evaluated with flow cytometry after the staining with appropriate fluorescent monoclonal antibody. The distribution of cell cycles was analyzed by propidium iodide staining and dead cells by 7-aminoactinomycin live staining. RESULTS: 100 μmol/L and 50 μmol/L of Ber had significant inhibition of the expression of CD69 on T cells stimulated with PDB plus Ion or PHA, while effect of 25 μmol/L Ber was not significant. And as time of action extended, the extent of inhibition decreased. For the expression of CD25, Ber at the concentrations as above all exerted significant inhibitory effect in a dose-dependent manner. Moreover, Ber could block lymphocytes cell cycle progression from G₀/G₁ phase to S and G₂/M phase without phase specificity. Besides, live staining analysis revealed that Ber did not have significant cytotoxicity on lymphocytes. CONCLUSIONS: Ber significantly inhibits the expression of early and mid activation antigens of T cells and also blocks the progression of lymphocytes cell cycles. These results suggest that Ber exerts immunosuppression effect through inhibiting the activation and proliferation of T cells.     

典型光活化毒素α-三噻吩对棉铃虫和亚洲玉米螟Na~+-K~+-ATPase的抑制作用

以棉铃虫 H elicoverpa armigera和亚洲玉米螟 Ostrinia furnacalis为试虫 ,建立 Na+- K+-ATPase最佳反应系统 ,研究典型光活化毒素 α-三噻吩 (简称 α- T)对 Na+- K+- ATPase的影响。棉铃虫 Na+- K+- ATPase活力最佳测试条件为酶源蛋白浓度 6μg/ m L ,反应温度 35～ 4 0℃ ,反应时间6min;亚洲玉米螟则为酶源蛋白浓度 8μg/ m L,反应温度 35℃ ,反应时间 6min。近紫外光照 (30 0～4 0 0 nm )对棉铃虫和亚洲玉米螟离体 Na+- K+- ATPase活力基本没有影响 ,但对活体活力有很强的抑制作用。光照和无光照条件下 ,α- T对两种昆虫离体和活体 Na+- K+- ATPase活力均有不同程度的抑制作用。光照组 α- T对亚洲玉米螟 Na+- K+- ATPase的抑制率高于无光照组 ,且处理浓度或剂量越高 ,其抑制率越大 ;对棉铃虫 Na+- K+- ATPase抑制作用不显著     

玉米螟赤眼蜂适宜生境的研究和利用:I.玉米螟赤眼蜂在不同生境中的分布与种群消长

本文通过对华北地区有代表性的作物生境，采用人工挂卵的方法，系统调查研究了玉米螟赤眼蜂在１７种生境中的分布和种群动态。结果表明，玉米螟赤眼蜂在不同生境中的分布、发生时间和种群数量有所不同，说明其对生境有一定的选择性。玉米螟赤眼蜂自然种群消长有４个峰，其中以春甘薯田的发生时间最长，种群数量最大，最具代表性。这４个峰在春高粱间作菜豆、春花生、平作夏玉米和夏玉米间作直立型绿豆这４种生境中也不同程度地出现。间作豆科作物可在一定程度上提高玉米螟赤眼蜂的寄生率。玉米螟赤眼蜂种群数量年度间变异较大，特别是干旱的影响最为明显。     

玉米螟赤眼蜂适宜生境的研究与利用:Ⅲ.夏玉米间作匍匐型绿豆对赤眼蜂的增诱作用及其在穗期玉米螟防治中的利用

本文就夏玉米间作匍匐型绿豆对玉米螟赤眼蜂增诱作用及其在穗期玉米螟防治中利用的可行性进行了研究。结果表明，夏玉米间作匍匐型绿豆结合接种式放蜂区，与平作夏玉米结合接种式放蜂区和不放蜂对照区相比，明显提高了玉米螟赤眼蜂对螟卵的寄生率，１９９２年三者人工挂卵的卵块总寄生率分别为２６．７％、３．６％和０；１９９３年分别为２８．０％、６．６％和１．０％，自然落卵的寄生率分别为６９．１％、２２．４％和４．６％。１９９４年用心叶期抗螟品种间作绿豆结合接种式放蜂区，人工挂卵的卵块总寄生率为３０．７％，而平作夏玉米不放蜂对照区仅为２．５％；自然落卵的卵块寄生率前者为５６．２％，后者为１２．３％。心叶期抗螟品种间作匍匐型绿豆结合接种式放蜂区、心叶期抗螟夏玉米平作不放蜂和感螟品种不放蜂对照区的平均百株蛀孔数分别为５４．８、１０２．６和２７７．２个，放蜂区与两个不放蜂对照区相比，对玉米螟的防效分别为４６．６％和８０．２％。试验结果显示采用心叶期玉米抗螟品种间作匍匐型绿豆，并接种释放少量赤眼蜂等综合措施对穗期玉米螟害有明显的控制作用     

散养湘黄鸡常见病的临床表现特点及其防制

湘黄鸡进行专业户(场)散养时，由于生产方式不同于舍饲群养，其生产环境、食物结构和易感病种类都必然发生变化。对此，笔者结合临床所遇病例进行了研究总结，对散养湘黄鸡的几种常发病的病因、病理、临床表现及防治特点等方面进行了介绍。     

检测猪流行性腹泻病毒的R-PCR方法的建立

根据猪流行性腹泻病毒 (PEDV)的N基因自行设计和合成了一对可扩增长度为 641bp目的片段的引物 ,成功地建立了检测的猪流行性腹泻病毒的RT PCR方法。对猪轮状病毒 (PRV)、猪传染性胃肠炎病毒 (TGEV)的RT PCR检测结果均呈阴性。对PEDV JS株的RT PCR产物的序列分析表明 ,与CV777株的同源性为 97 3 %。     

不同培养条件对鲍鱼菇菌丝生长的影响

通过不同温度、pH值及培养基含水量处理 ,对鲍鱼菇菌丝生长状况进行了研究。结果表明鲍鱼菇菌丝生长适宜的温度范围为 2 0～ 31℃ ,最适温度为 2 5～2 8℃ ;pH值适宜的范围为 4 0～ 7 0 ,最适pH值为 5 5～6 0 ;培养基含水量适宜的范围为 6 0 %～ 80 % ,最适含水量为 80 %。     

沙尘物质的来源与防治途径

本文分析了沙尘暴形成的自然过程和危害特征,并探讨了内蒙古沙源区土壤颗粒物质的含量,指出沙尘暴的沙尘来源主要是退化草原、活化的沙地和裸露坡耕地等。同时根据风沙流运移规律及其和土壤颗粒的关系,提出了防治沙尘暴的关键技术原理,并探讨了有效控制沙尘暴的技术途径。     

Effect of EGFP gene transfection on the cell cycle distribution of primary cultured human chondrocytes

AIM: To investigate the effect of enhanced green fluorescence protein (EGFP) gene transfection on the cell cycle distribution of primary cultured human chondrocytes in order to establish a tracking method of cultured human nasoseptal chondrocytes. METHODS: pEGFP-N1 plasmid was amplified in E.coli, and purified by high purity kit. Primary cultured human chondrocytes,which were initially obtained from the nasoseptal cartilage, were cultured in vitro and transferred with pEGFP-N1 by means of electroporation with Amaxa nucleofector device. Transfering process and transient expression were evaluated by laser scanning confocal microscope (LSCM), the transfer efficiency and the cell cycle distribution were evaluated by flow cytometry. RESULTS: There was significant expression of EGFP at 24 h after transferring. The transfection efficiency of pEGFP-N1 into primary cultured human chondrocytes reached 35.37％ at 48 h. It didn't affect the process of cell adherance and had no effect on the cell cycle distribution. CONCLUSION: Primary cultured human chondrocytes, which were transfected with pEGFP, are alive in vitro, and the transferring process doesn't affect the cell cycle distribution. These results suggest that pEGFP-N1 is an ideal transient expression vector for primary cultured human chondrocytes and it might be a well tracer in construction tissue engineered cartilage.     

Proteomic analysis of the effects of tumor necrosis factor-α on endothelial cells

AIM: To investigate the affected proteins by tumor necrosis factor (TNF)-α in endothelial cells, and further explore the potential molecular mechanism of TNF-α on endothelial cells. METHODS: Nitric oxide (NO) production in the cultured human umbilical vein endothelial cells (HUVECs) was measured by a NO assay kit. Proteomic alterations were analyzed using two-dimensional electrophoresis, and peptide mass fingerprinting with matrix-assisted laser desorption/ionization-time of flight mass spectrometry. RESULTS: NO production in HUVECs decreased significantly after TNF-α treatement. Proteomics analysis showed 21 protein spots were changed including 9 spots that were increased and 11 spots that were decreased after TNF-α stimulation, and 1 spot was only detected in TNF-α activated cell gels. CONCLUSIONS: Decreased the expression of ecNOS by TNF-α might result in decreased NO production. Up-regulated MAP/ERK kinase 3 expression might imply that TNF-α activates the expression of adhesion molecules. Cytoskeletal protein actin is also involved in TNF-α injuried HUVECs. Proteomic analysis can find some clues for identifying new potential target of TNF-α.