NIH3T3 cell proliferation and cell cycle in the conditions of hypoxia or low nutrition and its response to bFGF

AIM: To investigate NIH3T3 cell proliferation and cell cycle in the condition of hypoxia or low nutrition and its response to bFGF, and to explore the pathophysiological changes of fibroblast under hypoxic or low nutrional conditions.METHODS: The cells were placed in anaerobic workstation where the mixture gas was given to simulate hypoxic environment. Partial oxygen pressure (PO2) of medium was controlled in 27 mmHg, 44 mmHg and 175mmHg. NIH3T3 cells were cultured with low nutritional medium contained new bovine serum (NCS) less than 10% to simulate low nutritional environment. MTT assay was used for observing cell activity and flow cytometry for cell cycle analysis.RESULTS: Under 44 mmHg PO2, no obvious difference was shown between hypoxia group and normal group. Under 27 mmHg PO2, the proliferation activity of NIH3T3 cells was significantly lower than that in normal group (P<0.01), as well as the cell numbers in G0-G1 phase increased (P<0.05), S phase decreased (P<0.01). bFGF had no effect on cell proliferation. In 0.5% NCS medium, the NIH3T3 cell proliferation speed decreased (P<0.01) and cell cycle was arrested at G0-G1 (P<0.01). The proliferation speed was improved by bFGF (P<0.01).CONCLUSION: In lower PO2 or lower nutrinal condition, fibroblast proliferation activity is inhibited by cell cycle arrest in G0/G1 phase. However the decreasing proliferation in low nutritional medium could be improved by external bFGF.     

The effect of TNF-related apoptosis-inducing ligand on the activity of nuclear kappa B in prostate cancer cell line PC-3M

AIM: To investigate the activation and inactivation of nuclear factor kappa B (NF-κB) when tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is applied to induce the apoptosis of androgen-independent prostate cancer cell line PC-3M.METHODS: After the treatment of TRAIL or LPS at different doses, we tested the nuclear translocation of NF-κB by cell immunohistochemical staining and electrophoretic mobility shift assay(EMSA), and evaluated the level of IκB by RT-PCR under pyrrolidine dithiocarbamate (PDTC) treatment. RESULTS: EMSA and cell immunohistochemical analysis showed that the translocation of NF-κB was significantly activated when PC-3M cells were treated with TRAIL or LPS (P<0.05). The pretreatment of PDTC upregulated the expression of IκB and blocked the nuclear translocation of NF-κB.CONCLUSION: TRAIL remarkably stimulates the activation of nuclear NF-κB in androgen-independent prostate cancer cells. On the other hand, the translocation of NF-κB can be significantly and efficiently inhibited in PC-3M cells by pretreatment with PDTC. The increased expression of IκB might be a clue for this inhibition, which means the possible way to enhance the effect of TRAIL in the apoptosis of prostate cancer cells.     

Effect of human tissue factor pathway inhibitor gene transfection in vein grafts on thrombus formation and early patency rate

AIM: To reduce thrombus formation after coronary artery bypass graft,we investigated the antithrombotic effect of human tissue factor pathway inhibitor (TFPI) gene delivery on vein grafts. METHODS: The eukaryotic expressed plasmid vector pCMV-(Kozak)TFPI was constructed. Through pressurizing infusion,vein endotheliocytes were transfected with cationic liposome containing the plasmid vector pCMV-(Kozak)TFPI. After operation, vein grafts were harvested at third day for immunohistochemical, RT-PCR and Western blotting analysis of exogenous gene expression and for observation of thrombus formation by pathological method and scanning electron microscopy. At 30th days, the patency rate was recorded by vessel Doppler ultrasonography. RESULTS: Human TFPI mRNA and protein were detected in TFPI gene transferred vein grafts. Thrombosis was found in 8 animals of empty plasmid control group and in 7 animals of empty control group, but in only 1 of the TFPI group (P<0.05). Thirty days after operation, 5 vein grafts were occluded in both empty plasmid control group and empty control group, but none of vein grafts were occluded in TFPI group (P<0.05). The endothelial surfaces of the vein grafts in both control groups were covered with aggregated erythrocytes and platelets, but not in TFPI group. CONCLUSION: Human tissue factor pathway inhibitor gene transfection reduces thrombus formation and improves early patency rate in vein grafts.     

Effect of propolis water extract on apoptosis of human umbilical vein endothelial cells in vitro

AIM: To explore the effect of water extract propolis (WEP) from Taishan on apoptosis of human umbilical vascular endothelial cells (HUVECs) induced in vitro by tumor necrosis factor-α (TNF-α). METHODS: HUVECs were collect by digestion-perfusion and cultivated. TNF-α at concentration of 50 μg/L was administrated to induce the apoptosis of HUVECs. After injury, HUVECs were treated with WEP at concentrations of 50, 100, and 200 mg/L, respectively, for 24 h. Apoptosis was evaluated by terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) and flow cytometry (FCM). RESULTS: Apoptosis index in injured group was significantly higher than that in control group, and decreased significantly after treating with WEP at concentrations of 50, 100, and 200 mg/L, respectively (P<0.01). CONCLUSION: WEP may be useful for protection of vascular endothelial cells by inhibiting apoptosis.     

高山反季节栽培珍稀菇试验

杏鲍菇、真姬菇、鸡腿菇3个珍稀菇均属中低温型菌类,市场前景看好。通过高山反季节栽培珍稀菇试验得出,利用高海拔地区的自然条件,可选择3种菇的最佳栽培时间及烂菇、病虫害发生等的气象调控管理办法,为山区建立珍稀菇无公害生产基地,提供了科学的气象依据和技术借鉴。     

辣椒在不同温度条件下萌发特性的研究

用5种温度（15℃、20℃、25℃、30℃、35℃）处理（以25℃处理为对照）,研究各温度下“湘辣妹”尖椒品种种子的发芽率、发芽势及发芽指数的变化规律,为生产应用提供依据。结果表明：“湘辣妹”尖椒品种种子的发芽适宜温度范围为25-30℃,最佳发芽温度为25℃。     

苹果bZIP转录因子基因MdAREB2功能的初步研究

对‘嘎拉’苹果中的1个bZIP转录因子基因MdAREB2(序列号:MDP0000248567)进行功能初步研究。蛋白进化树分析表明,苹果MdAREB2与拟南芥AtAREB2具有很高的同源性。利用PlantCare数据库进行启动子顺式作用元件的预测分析,MdAREB2启动子序列中存在脱落酸响应元件ABRE。实时定量PCR检测表明,MdAREB2明显受ABA诱导。拟南芥种子萌发阶段经过0.5和2μmol·L~(-1)ABA处理后发现突变体abi5中过量表达MdAREB2能够恢复对ABA的敏感性。拟南芥幼苗生长阶段,经过20μmol·L~(-1) ABA处理后发现,突变体abi5中过量表达MdAREB2能够部分恢复对ABA的敏感性。