Attenuated Salmonella carrying pGRIM-19-si-survivin co-expression plasmid inhibits growth of prostate cancer subcutaneous xenografts in vivo

AIM：To explore the effects of pGRIM-19-si-survivin co-expression plasmid carried by human attenuated Salmonella on prostate cancer subcutaneous xenograft growth in nude mice. METHODS：Prostate cancer xenograft model was established in nude mice. Co-expression plasmids carried by attenuated Salmonella were introduced by intraperitoneal injection. The xenograft volumes were monitored timely. Immunohistochemical staining, RT-PCR and TUNEL assay were applied to investigate the related mechanisms that pGRIM-19-si-survivin inhibited tumor growth in vivo. RESULTS：Compared with psi-survivin and pGRIM-19 carried by attenuated Salmonella (control groups), the tumor volumes were reduced markedly in pGRIM-19-si-survivin plasmid group. The mean shrinkage rates were 2.36 and 3.02 times. pGRIM-19-si-survivin co-expression plasmid carried by attenuated Salmonella inhibited survivin expression but strengthened GRIM-19 expression obviously (P<0.05). The mRNA expression of apoptosis-related proteins such as Bcl-xL, Stat3, cyclin D1 and c-Myc was inhibited, and the vascular endothelial growth factor (VEGF) mRNA and Ki67 protein were also inhibited, but the caspase-3 mRNA expression was up-regulated (P<0.05) with significant cell apoptosis. CONCLUSION： pGRIM-19-si-survivin co-expression plasmid carried by human attenuated Salmonella inhibits the growth of prostate cancer subcutaneous xenografts in nude mice by promoting cell apoptosis and inhibiting prostatic cancer proliferation.     

High concentration of extracellular ATP causes autophagy and apoptosis of SH-SY5Y cells

AIM：To examine the effects of high concentration of extracellular ATP on human neuroblastoma SH-SY5Y cell injury. METHODS：Cultured SH-SY5Y cells were grouped according to the concentrations of ATP and treatment time. The cell viability was detected by CCK-8 assay. The variation of autophagic vacuoles was observed with monodansylcadaverine staining. The cell apoptosis was analyzed by Hoechst 33258 staining. Meanwhile, apoptotic rate was detected by flow cytometry. The levels of caspase-3 and microtubule-associated protein 1 light chain 3-Ⅱ (LC3-Ⅱ) were determined by Western blotting. RESULTS：Compared with control group, the survival rate of SH-SY5Y cells was significantly reduced by ATP at different concentrations (3, 6, 9, 12 and 15 mmol/L for 3 h) and different treatment time (1, 2, 3 and 6 h with 6 mmol/L ATP, peaking at 3 h). The autophagic vacuoles of SH-SY5Y cells were significantly increased at 1 h with ATP treatment, trended to decrease over time and returned to control level at 6 h. The protein expression of LC3-Ⅱ was significantly increased at 1 h with ATP treatment, which was consistent with the time points of increasing autophagic vacuoles. LC3-Ⅱ expression level gradually decreased at 2~3 h with ATP treatment, and returned to control level at 6 h. Compared with control group, the apoptotic rate and the expression level of caspase-3 were enhanced synchronously. The peak of apoptotic rate occurred at 3 h, and kept until 6 h.The level of cleaved caspase-3 expression peaked at 6 h. CONCLUSION：High concentration of extracellular ATP induces the autophagy and apoptosis of SH-SY5Y cells. The increased autophagy shows up, followed by the climax of apoptosis until 6 h. With the prolonged duration of ATP, apoptosis is the main process in the cells.     

小株采种阳畦中白菜幼苗症状的识别

目前,小株采种是白菜杂交一代种子生产的主要方式,而播种和育苗环节是小株采种的两个关键技术环节,阳畦育苗过程中如何识别幼苗受害症状至关重要。     

溧阳白芹铅污染原因探析

为寻找溧阳白芹铅超标原因,探索生态修复和控制措施,溧阳市蔬菜办公室在溧阳城郊溧阳白芹基地进行了水、土、肥、产品等四大类样品的铅含量检测,对照相关标准,通过对试验区生态环境的调研和铅污染评价,认为溧阳市城郊溧阳白芹主产区的土壤、基肥、培土与否及铅富集等对溧阳白芹重金属铅污染影响不明显,灌溉水则是重金属铅污染的主因。     

浅水芹夏秋轻简栽培技术研究

为探索浅水芹夏秋轻简栽培技术,研究了不同稻草覆盖量和覆盖方式对水芹生长的影响。试验结果表明,浅水芹夏秋栽培宜采用免催芽直接排种;覆盖方式以遮阳网大棚覆盖为最佳,其次为稻草覆盖,最适宜的稻草覆盖量为200~250 kg/667 m2。     

孝感市蔬菜产业现状、存在问题及对策

孝感市是湖北省三大蔬菜主产区之一,具有发展蔬菜产业的有利条件,产业发展迅速,但仍存在现代化水平不高、组织化程度低、抵御市场风险能力弱等一系列问题,通过调查研究,提出了发展蔬菜生产的几点对策。     

花脸香蘑3种不同栽培模式比较试验

通过对花脸香蘑3种不同的栽培模式在栽培过程中的幼蕾总数、有效子实体数和产量进行比较,结果表明,栽培模式3（生料床栽法）的有效子实体数和幼蕾总数居中,产量最高,是最理想的栽培模式。     

利用牡蛎制作海鲜调味汁的试验

研究了混合酶水解牡蛎蛋白质的技术条件，并和单酶水解结果进行了比较。结果表明，混合酶水解可提高水解率和水解液中氨基态氮(AAN)的含量，同时改善了水解液风味。     

B细胞淋巴瘤-2家族蛋白与细胞凋亡简

细胞凋亡是由多基因控制的细胞自主有序的死亡,以维持内环境稳定。其在多细胞生物的组织分化、器官发育、机体稳态的维持中有重要意义。细胞凋亡可促进因感染、损伤所致的细胞死亡并被机体清除,临床上细胞凋亡与许多疾病有直接关系。B细胞淋巴瘤-2（Bcl-2）家族蛋白是参与细胞凋亡的重要调节分子,既可抑制也可促进细胞凋亡。作者概述了Bcl-2蛋白家族成员、结构特点、Bcl-2蛋白家族与细胞凋亡的关系及生物学意义。     

Smad泛素化调节因子2siRNA的筛选及转染原代肾小管上皮细胞条件的优化简

试验旨在优化Smad泛素化调节因子2（Smurf2） siRNA最佳转染条件,筛选最佳siRNA干扰片段,进而实现对Smurf2基因的瞬时沉默,为研究Smurf2基因在马兜铃酸肾病（aristolochic acid nephrohathy,AAN）中的作用奠定基础。本研究通过培养小鼠原代肾小管上皮细胞（renal tubular epithelial cells,RTECs）,并以脂质体Lipofectamine^TM 2000为转染介质,将Smurf2 siRNA转染入RTECs;通过观察绿色荧光的表达量及Real-time PCR反应优化转染条件,转染后Real-time PCR检测mRNA表达抑制率。CCK-8法检测Smurf2 siRNA复合物对RTECs活性的影响;同时,用Real-time PCR和Western blotting检测不同位点Smurf2 siRNA对Smurf2 表达的影响。结果显示,当Lipofectamine ^TM 2000与siRNA比例为1.5 μL∶30 pmol时,转染效率最高,为70%～80%;Smurf2-619 siRNA干扰效果最明显;与正常组相比,转染siRNA组的Smurf2蛋白表达水平显著下降（P<0.05）。最终确定了Smurf2 siRNA最佳转染条件,其中Smurf2-619 siRNA对Smurf2 表达的抑制率最高。