草地贪夜蛾体表靶向TRPV1的毒素分子筛选及其功能研究

[目的]探究草地贪夜蛾诱发人畜危害的分子机制,以草地贪夜蛾诱发人畜呼吸道炎症、疼痛等危害的潜在生理靶点(瞬时电位感受器香草酸受体1,TRPV1)为切入点,揭示草地贪夜蛾体表物质诱发人畜危害的毒素物质基础和生理靶点。[方法]通过凝胶分子筛以及高效液相色谱等方法对草地贪夜蛾体表物质进行分离和纯化,结合膜片钳电生理技术筛选草地贪夜蛾体表物质中靶向TRPV1的活性毒素组分。[结果]从草地贪夜蛾体表物质中分离纯化到一种能够高效(100 mg/L)激活TRPV1的毒素组分V-7,该组分能特异性作用于TRPV1,而对常见离子通道类膜蛋白生理受体(如钠离子通道NaV1.4、NaV1.5、NaV1.7,以及钾离子通道KV1.1、KV2.1、KV4.1)没有作用。[结论]从草地贪夜蛾体表混合物中可分离得到一种高效且特异性激活动物生理靶点TRPV1的毒素组分,部分揭示了外来入侵农业害虫草地贪夜蛾诱发人畜危害的物质基础及生理靶点。

松材线虫体壁物的厚度和糖含量比较

为进一步弄清松材线虫的致病机理,该文对松树上分离的松材线虫、拟松材线虫和小杆线虫的体壁物进行了初步研究。通过电镜观察和可溶性糖含量分析,发现松材线虫体表有一层很厚的物质,而拟松材线虫和小杆线虫体表比较光滑;松材线虫比其他两种线虫体表有更多的糖类物质。研究同时提出,松材线虫和拟松材线虫体表物质的厚度和糖含量,可能与二者的致病性有密切关系。

副干酪乳杆菌M5-L抑制宋内志贺氏菌黏附作用影响因素的研究

研究副干酪乳杆菌M5-L抑制宋内志贺氏菌(S.sonnei)对HT-29细胞黏附的作用及其影响抑制黏附作用的表面分子分析。结果表明M5-L能够显著的抑制S.sonnei的黏附作用,在排除、竞争和取代黏附实验中,抑制率分别为55%、33%和30%,差异显著(p<0.05),高碘酸钠处理后,M5-L的抑制黏附作用没有变化,表明碳水化合物并没有参与到黏附抑制过程中。而经过5mol/L LiCl处理后,M5-L的抑制黏附作用下降,说明S-层蛋白参与了M5-L抑制S.sonnei对HT-29细胞的黏附作用。此外,M5-L的S-层蛋白能够显著抑制S.sonnei的黏附作用。

Development of a Thermal Fogger-specific Sedimentation Stabilizer

In order to solve the drifting away of thermal fog droplets during thermal spraying and the incompatibility between fog droplet carrier and conventional com- mercial agro-chemicals, the fog droplet carrier, surfactant, condensation nucleus ma- terial and antifreeze, dispersant, thickener and defoamer were screened and assem- bled to develop a thermal fog sedimentation stabilizer in this study, thereby provid- ing technical support for application and promotion of thermal spraying technology in pest and disease control in crops.

Effect of naked eukaryotic expression plasmid encoding rat augmenter of liver regeneration on acute hepatic injury and hepatic failure in rats

AIM: To study the protective effect of eukaryotic expression plasmid encoding augmenter of liver regeneration (ALR) on acute hepatic injury and hepatic failure in rats. METHODS: The PCR-amplified ALR gene was recombined with pcDNA3 plasmid, and used to treat rats with acute hepatic injury. The rats with acute hepatic injury induced by intraperitoneal injection of 2 mL/kg 50% carbon tetrachloride (CCl4) were randomly divided into saline control group and recombinant pcDNA3-ALR plasmid treatment groups. Recombinant pcDNA3-ALR plasmid DNA (50 or 200 μg/kg) was injected into the rats with acute hepatic injury intravenously, intraperitoneally, or intravenously and intraperitoneally in combination 4 h after CCl4 administration, respectively. The recombinant plasmid was injected once per 12 h into all treatment groups four times, and the rats were decapitated 12 h after the last injection. Hepatic histopathological alterations were observed after HE staining, the expression of proliferating cell nuclear antigen (PCNA) in liver tissue was detected by immunohistochemical staining, and the level of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was determined by biochemical method. The recombinant plasmid DNA (200 μg/kg) and saline were intraperitoneally injected into the rats with acute hepatic failure induced by intraperitoneal injection of 4 mL/kg 50% CCl4 after 4 h of CCl4 administration, respectively. Rats living over 96 h were considered as survivals.RESULTS: The sequence of ALR cDNA of recombinant pcDNA3-ALR plasmid was accordant with the reported sequence of rat ALR cDNA. After the rats with acute hepatic injury were treated with recombinant pcDNA3-ALR plasmid, the degree of liver histopathological injury markedly decreased. The pathologic liver tissues, in which hepatic degeneration and necrosis of a small amount of hepatocytes and a large amount of infiltrating inflammatory cells were observed, and they became basically normal in the most effective group after four times of injection of recombinant pcDNA3-ALR plasmid. The indexes of PCNA significantly increased in the recombinant pcDNA3-ALR plasmid treatment groups compared to model group. The level of serum AST and ALT remarkably reduced in recombinant pcDNA3-ALR plasmid treatment groups compared to model group. The results showed that the effect of 200 μg/kg recombinant pcDNA3-ALR plasmid in the rats with acute liver injury was stronger than that of 50μg/kg pcDNA3-ALR DNA.The effect of intravenous injection of recombinant pcDNA3ALR plasmid was better. After the rats with acute hepatic failure were treated with recombinant pcDNA3-ALR plasmid,the survival rate (40%) significantly increased in treatment groups compared to control group (15%, P＜0.01).CONCLUSION: The ALR gene may play an important role in relieving acute hepatic injury and hepatic failure by promoting hepatic cell proliferation and reducing level ofAST and ALT in CCl4-intoxicated rats.

Modeling of mass transfer characteristics of bubble column reactor with surfactant present

Danckwert’s method was used to determine the specific interfacial area, a, and the individual mass transfer coefficient, kL, during absorption of CO2 in a bubble column with an anionic surfactant in the carbonate-bicarbonate buffer solution and NaAsO2 as catalyst, the presence of which decreases the specific interfacial area and the individual mass transfer coefficient. The specific interfacial area and the individual mass transfer coefficient increase with increasing su- perficial gas velocity. The specific interfacial area decreases whereas the individual mass transfer coefficient increases with increasing temperature. The results of experiments were used to determine the dependence of a, kL, and kLa on the surface tension, the temperature of the absorption phase, and the superficial velocity of the gas. The calculated results from the correlation were found to be within 10% deviation from the actual experimental results.

Mg2＋-ion Conducting Polymer Electrolytes： Materials Characterization and All-Solid-State Battery Performance Studies

For All-Solid-State battery applications, Mg2＋-ion conducting polymer electrolytes and Mg-metal electrode are currently considered as alternate choices in place of Li＋-ion conducting polymer electrolytes/Li-metal electrode. Present paper reports fabrication of All-Solid-State battery based on the following Mg2＋-ion conducting nano composite polymer electrolyte （NCPE） films： [85PEO： 15Mg（C104）2] ＋ 5% TiO2 （〈 100 nm）, [85PEO： 15Mg（CIO4）2] ＋ 3% SiO2（-8 nm）. [85PEO： 15Mg（CIO4）2] ＋ 3% MgO （〈 100 nm）, [85PEO：15Mg（C1O4）2] ＋ 3% MgO （-44 μm）. NCPE films were prepared by hot-press technique. Solid Polymer Electrolyte （SPE） composition： [85PEO： 15Mg（CIO4）2], identified as high conducting film at room temperature, has been used as ISt--phase host and nano/micro particles of active （MgO）/passive （SiO2, TiO2） fillers as IInd-phase dispersoid. Filler particle dependent conductivity studies identified above mentioned NCPE films as optimum conducting composition （OCC） at room temperature. Ion transport behavior of SPE/NCPE film materials was investigated previously. Present paper reports materials characterization and cell performance studies on All-Solid-State batteries： Mg （Anode） Ⅱ SPE or NCPE films tt C＋MnO2＋Electrolyte （Cathode）. Open circuit voltage （OCV） obtained was in the range： 1.79-1.92 V. The batteries were discharged at room temperature under different load conditions and some important battery parameters have been evaluated from plateau region of cell-potential discharge profiles. All the batteries performed quite satisfactorily specially under low current drain states.

Action Mechanisms of Arbuscular Mycorrhizal Fungi in Phosphorus Uptake by Capsicum annuum L.

A pot experiment was conducted to investigate the action mechanisms phorus （P） uptake of Capsicum annuum L. in a sterilized fossil Oxisol of arbuscular mycorrhizal （AM） fungi in phos- Three P levels of 0, 10 and 200 mg kg-1 soil （P0, P10 and P200, respectively） without and with AM fungal inoculation were applied as Ca（H2PO4）2-H20. Shoot dry matter yields and shoot P uptake increased significantly （P 〉 0.05） by the inoculation of AM fungi at P0 and P10. Root length and P concentration in soil solution increased with the inoculation of AM fungi but the root：shoot ratio decreased or remained constant. Around 50% roots of inoculated plants were infected by AM and the external hyphae amounted to 20 m g^-1 soil at P10 and P200. The hyphae surface area of the infected root cylinder amounted to 11 and 2 cm^2 cm^-2 root at P0 and P10, respectively. The increased P uptake of inoculated plants was mainly because of an up to 5 times higher P influx of the infected root. Model calculations showed that the root alone could not have achieved the measured P influx in both infected and non-infected roots. But the P influx for hyphae calculated by the model was even much higher than the measured one. The P uptake capacity of hyphae introduced in the model was too high. Model calculations further showed that the depletion zone around roots or hyphae was very narrow. In the case of the root only 7% of the soil volume would contribute P to the plant, while in the case of hyphae it would be 100%. The results together with the model calculations showed that the increased P uptake of AM inoculated plants could be explained partly by the increased P concentration in the soil solution and by the increased P absorbing surface area coming from the external hyphae.

A novel type of functional epirubicin liposomes modified with DSPE-PEG_(2000)-cyclopamine conjugate for eliminating heterogeneous breast cancer cells

Common chemotherapy is unable to eliminate the heterogeneous side population of cancer cells （such as cancer stem-like cells）, resulting in poor prognosis. The heterogeneity of cancer cells causes an extensive multidrug resistance through the aberrantly active Hedgehog （Hh） signaling pathway. Cyclopamine is a chemical compound that can block Hh signaling pathway, and a combination use of cyclopamine with anticancer drug would be beneficial for killing heterogeneous cancer cells. In the present study, we aimed to develop a kind type of fimctional drug liposomes for eliminating heterogeneous cancer, The study was performed on human breast cancer cells. A distearoylphosphoethanolamine polyethylene glycol （DSPE-PEG2000）-cyclopamine conjugate was newly synthesized by a nucleophilic substitution reaction, and confirmed by MALDI-TOF mass. An HPLC method was established and validated for qualification of epirubicin. Functional epimbicin liposomes were successful constructed by modifying with DSPE-PEG2o00-cyclopamine, displaying a particle size in nano-scale （approximately 98 nm） and a high epirubicin encapsulation （〉97%）. The CD44＋/CD24-side population was characterized in defining heterogeneous breast cancer cells. As compared with regular epirubicin liposomes, fimctional epirubicin liposomes exhibited an evidently enhanced cellular drug uptake and a significant killing effect in overall breast cancer cells. In conclusion, the functional epirubicin liposomes could be a useful drug delivery carrier for eliminating heterogeneous breast cancer cells.

Effect of substance P on gene expression of transforming growth factor β-1 and its receptors in rat's fibroblasts

Objective: To investigate the effect of substance P (SP) on gene expression of transforming growth factor β-1 (TGFβ-1), transforming growth factor receptor-1 (TGFR-1) and transforming growth factor receptor-2 (TGFR-2) in fibroblasts cultured in vitro from rat’s granulation tissues. Methods: The fibroblasts from the granulation tissues in the skeletal muscle of rat’s hind limbs injured by formaldehyde were cultured in vitro. When different concentrations (10 -9-10 -5 mol/L) of SP were added into the culture medium, the changes of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the cultured fibroblasts were observed with reverse transcription polymerase chain reaction at different intervals (0, 3, 6, 12 and 24 hours after incubation). Results: The gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts cultured from rat’s granulation tissues was up-regulated by SP. The peak level of the mRNA expression was found at 10 -8 mol/L SP and the up-regulation effect was not found at 10 -5 mol/L and 10 -6 mol/L. The peak levels of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts treated with SP were achieved at 6 and 12 hours, respectively. Conclusions: SP has up-regulation effect on the gene expression of TGFβ-1, TGFR-1 and TGFR-2 in fibroblasts from rat’s granulation tissues in vitro, and the effect is related to different stimulating concentrations of SP. It may be concerned with proliferation and differentiation of fibroblasts and formation of scar tissues during wound healing.