Percutaneous comprehensive cryoablation for metastatic esophageal cancer after failure of radical surgery

Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis.     

高浓度氯苯优势降解菌的筛选及其降解酶的纯化

[目的]分离纯化出一株高浓度氯苯优势降解菌株,对其所产氯苯降解酶进行分离与纯化,为该菌株及其氯苯降解酶的研究提供理论参考.[方法]利用梯度富集培养技术和无菌滤纸片平板法分离菌株,通过形态特征及16S rRNA基因序列分析初步鉴定菌株,用气相色谱法测定培养液中氯苯浓度,以单位细胞氯苯降解率评价菌株对氯苯的降解能力,以氯苯降解率表示氯苯降解酶的活性.取纯化菌株的发酵酶液制备粗酶液,经硫酸铵梯度盐析、透析脱盐、DE-52离子交换层析、G-100凝胶层析和透析浓缩后,进行SDS-PAGE凝胶电泳检验酶的纯度并测定酶的分子量.[结果]从氯苯长期驯化的成熟期活性污泥中筛选到一株以氯苯为唯一碳源和能源的氯苯优势降解细菌LW13,该菌株在以2000 mg/L氯苯为唯一碳源的无机盐培养基中仍能正常生长,其单位细胞氯苯降解率可达1.37 ×10-10.扫描电镜观察到该菌株细胞大小约为2.3 ×0.8μm,长有数根端生鞭毛.16S rRNA基因序列相似性比较表明该菌株与Lysinibacillus fusiformis(溶藻菌)的相似性达95.5％.所纯化的氯苯降解酶为胞外酶,带正电荷,其分子大小约为57 kDa.整个纯化过程中酶纯化倍数化达8.0倍,酶活回收率达52.51％,酶量回收率达6.57％.纯化后的氯苯降解酶在30℃-55℃和pH在6.0-8.0之间都保持较高的酶活性,其最适反应温度和pH分别在40℃和pH8.0左右.[结论]所分离的氯苯优势降解菌属于Lysinibacillus属菌株,该菌株能有效降解高浓度(500-2000 mg/L)氯苯废水,通过逐级分离纯化,可获得氯苯降解酶纯酶,纯化指标符合分离纯化基本规律,纯化效果较为理想.     

转OvDREB2B基因陆地棉鉴定及其对水分渗透胁迫的分析

通过花粉管通道技术,以该实验室自育陆地棉品系TH₁和TH₂为材料,将诸葛菜(Orychophragmus vidaceus)抗逆转录因子OvDREB2B基因构建到植物表达载体后,导入棉花基因组,经卡那霉素筛选和分子鉴定表明目的基因已整合到棉花基因组中并表达。将T₁代转基因植株和受体对照在温室中栽培,待植株生长至四叶一心时,用不同渗透势的PEG-6000水溶液进行渗透胁迫处理,分析探讨转基因植株的抗旱效果及其抗旱机理。结果显示:当渗透势为0和0.5 MPa处理时,转基因植株和对照无明显差异;当渗透势为0.8 MPa和1.1 MPa处理时转基因植株较对照抗旱性明显提高。当渗透势为1.1 MPa处理96 h时,对照植株F_v/F_m降至0.2左右,而转基因植株仍正常生长,F_v/F_m值约为0.51,而且初始荧光（F₀）值、净光合速率（P_n）、胞间CO₂浓度（C_i）、蒸腾速率（T_r）等一系列参数转基因植株都明显优于对照,表明DREB2B基因能够提高棉花对水分胁迫的耐受性。     

Highly amplified electrochemiluminescence of peroxydisulfate using bienzyme functionalized palladium nanoparticles as labels for ultrasensitive immunoassay

An immunosensor based on the electrochemiluminescence (ECL) of peroxydisulfate was firstly proposed by coupling the cooperation of two enzymes to in situ generate coreactant with palladium nanoparticles (PdNPs) as catalyst for the ECL reaction. PdNPs were previously synthesized, which successfully attached to functional carbon nanotubes (FCNTs), to bind the secondary antibody and bienzyme (horseradish peroxidase and glucose oxidase). Then the prepared bioconjugates were introduced to the electrode via sandwich immunoreactions. Accordingly, a dramatically amplified ECL signal was obtained for that GOD catalyzed glucose to produce H(2)O(2) which was subsequently reduced by HRP to in situ generate O(2), then PdNPs as catalyst for the ECL reaction of peroxydisulfate/O(2). The present immunosensor was used to detect α-1-fetoprotein (AFP) and showed a wide linear range of 1×10(-5)-100ngmL(-1), with a low detection limit of 3.3fgmL(-1)(S/N=3). This new signal amplification strategy for preparation of the ECL immunosensor could be easily realized and has a potential application in ultrasensitive bioassays.     

Long-term effects of simulated acid rain stress on a staple forest plant, Pinus massoniana Lamb: a proteomic analysis

At present, acid rain has become one of the top ten global environmental issues. Acid rain causes slower growth, injury, or decline of forests. Some dramatic effects on forests have been observed in south China since the late 1970s and the situation is deteriorating. We carried out a comparative proteomic analysis on Pinus massoniana Lamb, a staple tree species widely distributed in middle and south China to gain a better understanding of tree response to acid rain at molecular level. Two-year-old P. massoniana saplings were treated with simulated AR (SiAR) or control solution, respectively, for 8 months. The changes in total protein profile of P. massoniana leaves were studied using two-dimensional differential gel electrophoresis (2D-DIGE). Among the total protein spots reproducibly detected on each gel, 65 spots representing 28 proteins were identified to be differentially regulated. These proteins were annotated in various biological functions, such as photosynthesis and energy metabolism, secondary metabolism, protein stability, amino acid and nitrogen metabolism and defense. Down-regulation of four key enzymes in the Calvin cycle identified that biomass loss by SiAR was mainly due to the inhibition of carbon fixation. Primary energy metabolisms involved in sucrose biosynthesis, glycolytic pathway and Krebs cycle, etc., were also disturbed after SiAR treatment. Specifically, most of up-regulated proteins were related to secondary metabolism, protein stability and defense, suggesting that in response to SiAR stress, plants started a variety of metabolic pathways to prevent cells from damage. Different from the herbaceous plants suffering SiAR, it revealed that secondary metabolites in P. massoniana play pivotal roles against SiAR. Protemoic techniques were demonstrated a reliable and robust tool to expand our understanding of differentially expressed proteins associated with acid rain stress on P. massoniana. Functional analysis of these proteins further revealed biochemical and physiological basis of the plant in response to acid rain and would provide strategies for breeding new acid rain tolerant tree species. To our knowledge, it is the first proteome report on the forest plant suffering long-term acid rain stress.     

Grape seed proanthocyanidin extracts prevent high glucose-induced endothelia dysfunction via PKC and NF-κB inhibition

In our study, it has been detected in vivo and in vitro that GSPE reversed high glucose-induced the increase of ICAM-1 and VCAM-1. It is shown that by western blotting detection, GSPE significantly inhibited the activation of NF-κB induced by high glucose while there was significant decrease of the expression of PKC with GSPE intervention. By adding the NF-κB blocker PDTC and the PKC inhibitor peptide 19–31(10^?6 M), no significant difference was found in the levels of VCAM-1 and ICAM-1 among GSPE group, the PKC inhibitor peptide 19–31-added GSPE group and the PDTC-added GSPE group. So the conclusion could be drawn that PKC inhibition must be involved in GSPE decreasing the level of ICAM-1 and VCAM-1.We proved for the first time that GSPE prevented high glucose-induced the increase of ICAM-1 and VCAM-1 by PKC and NF-κB inhibition. These findings show a novel mechanism of the action GSPE preventing endothelial dysfunction, which may have clinical application values.