Selenium Attenuates Adriamycin-Induced Cardiac Dysfunction via Restoring Expression of ATP-Sensitive Potassium Channels in Rats

The possible mechanism of adriamycin (ADR) and/or selenium (Se) deficiency-induced cardiac dysfunction, and cardioprotective effects of Se against ADR-induced cardiac toxicity were investigated in this study. Cardiac function was evaluated by plasma brain natriuretic peptide level and echocardiographic and hemodynamic parameters. Cardiac glutathione peroxidase (GPx) activity was assessed spectrophotometrically. Expression of ATP-sensitive potassium channels (K_ATP) subunits—SUR2A and Kir6.2—were examined by real-time PCR and Western blotting. The results showed that cardiac function and cardiac GPx activity decreased remarkably after administration of ADR or Se deficiency; more dramatic impairment of cardiac function and cardiac GPx activity were observed after co-administration of ADR and Se deficiency. Mechanically, it is novel for us to find down-regulation of K_ATP subunits gene expression in cardiac tissue after administration of ADR or Se deficiency, and more significant inhibition of cardiac K_ATP gene expression was identified after co-administration of ADR and Se deficiency. Furthermore, cardiac toxicity of ADR was found alleviated by Se supplementation, accompanied by restoring of cardiac GPx activity and cardiac K_ATP gene expression. These results indicate that decreased expression of cardiac K_ATP is involved in adriamycin and/or Se deficiency-induced cardiac dysfunction; Se deficiency exacerbates adriamycin-induced cardiac dysfunction by future inhibition of K_ATP expression; Se supplementation seems to protect against adriamycin-induced cardiac dysfunction via restoring K_ATP expression, showing potential clinical application in cancer chemotherapy.     

Zero effect of Bt rice on expression of genes coding for digestion,detoxification and immune responses and developmental performances of Brown Planthopper Nilaparvata lugens (Stål)

Transgenic Cry1Ac, Cry2Aa and Cry1Ca (Bt toxins) rice lines are well developed to manage lepidopteron pests in China. The impact of transgenic Bt rice on the non-target Brown Planthopper (BPH) has become an essential part of environmental risk assessment, however, scanty evidence is found addressing on developmental and molecular responses of BPH to the ingestion of Bt protein from transgenic rice. The focus of the current study is to examine the developmental characteristics and the expression profiles of gene in relation to digestion, detoxification and immune responses were examined. Our study strongly revealed that the tested Bt rice strains have no unfavorable effect on fecundity, survival and growth of BPH. Furthermore, each of the tested genes did not exhibit distinct expression pattern responding to non Bt parental cultivar, thus, it could be concluded that Bt rice have no detrimental effects on the physiological processes of digestion, detoxification and immune responses of BPH.     

对叶榕榕果内生细菌分离鉴定及抑菌活性的研究

【目的】为植物-内生细菌的生态关系研究, 以及植物内生细菌资源的利用提供一定的依据。【方法】采用微生物学传统分离培养的方法从对叶榕果实中分离到内生细菌54株, 通过限制性酶切分析(ARDRA)共有16个操作分类单元(Operational taxonomic units, OTUs), 对16株代表菌株16S rDNA序列系统发育分析。【结果】16个菌株都找到了与其相似性最高的菌株, 相似性达到95%?100%。其中6株为芽孢杆菌Bacillus属, 为对叶榕果实内生细菌优势菌属; 3株为Staphylococcus属, 2株为Pseudomonas属, 1株为Serrata属, 1株为非培养细菌的同源菌, 1株为Kocuria属, 1株为Delftia属, 还有1株为Acinetobacter属。【结论】这16株内生菌在系统发育树中明显聚为两大支; 在参与抑菌试验的14株内生菌中, 有13株对受试菌有不同程度的拮抗作用。尤其是其中的芽孢菌属的Swx15和不动杆菌属的Swx25菌株, 抑菌作用较强, 且有较广的抑菌谱性。     

杀菌剂对感染越冬桃小食心虫的白僵菌的抑制作用

【目的】桃小食心虫是我国果树上发生最普遍的食心类害虫,其室内人工饲养是综合防治研究的基础,但面临着田间越冬种群大量感染白僵菌死亡,给实验室种群的建立带来很大困难。因此筛选出对球孢白僵菌高效的杀菌剂用于解决桃小食心虫种群建立时感染白僵菌的问题。【方法】利用液体摇床振荡法和平皿十字交叉法测定16种常见杀菌剂对球孢白僵菌孢子萌发和菌丝生长的影响。【结果】筛选出9种杀菌剂,其中,腐霉利和中生菌素对孢子萌发的抑制效果好,常规用量抑制效果分别为97.88%±1.53%和93.22%±2.36%;抑霉唑和戊唑醇对菌丝生长的抑制效果明显,常规用量抑制效果分别达100.00%±0.00%和98.43%±0.99%;咪酰胺、丙环唑、噻菌灵、腈菌唑和吡唑醚菌酯对孢子萌发和菌丝生长的抑制效果都好。同时测定了这9种杀菌剂常规浓度及其5倍和10倍稀释液对桃小食心虫的毒力,结果表明有5种杀菌剂对桃小食心虫稍有不利影响。【结论】4种杀菌剂,中生菌素、戊唑醇、吡唑醚菌酯和噻菌灵可用于解决桃小食心虫种群建立时越冬幼虫的感染白僵菌问题。     

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.     

Actinopolyspora dayingensis sp. nov., a novel halophilic actinomycete isolated from a hypersaline lake

A novel halophilic, filamentous actinomycete, designated TRM 4064^T, was isolated from a hypersaline habitat in Sichuan Province, China. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain TRM 4064^T showed that it was most closely related to Actinopolyspora mortivallis (99.1 % sequence similarity). The sequence similarities between strain TRM 4064^T and other Actinopolyspora species with validly-published names were <97.0 %. However, it had relatively low mean values for DNA–DNA relatedness with the A. mortivallis DSM 44261^T (23.2 %). Optimal growth occurred at 37 °C, pH 7.0 and in the presence of 13 % (w/v) NaCl. The whole-cell sugar pattern consists of xylose, glucose, ribose and arabinose. The predominant menaquinones are MK-10(H₄) (38.2 %), MK-9(H₄) (25.1 %), MK-9(H₂) (28.6 %) and MK-8(H₄) (7.3 %). The major fatty acids are anteiso-C_17:0 (36.9 %) and iso-C_17:0 (19.3 %). The diagnostic phospholipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and two unknown phospholipids. The G+C content of the genomic DNA of the type strain is 66.3 mol%. Strain TRM 4064^T therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora dayingensis sp. nov. is proposed. The type strain is TRM 4064^T (= KCTC 19979^T = CCTCC AA 2010010^T).     

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.