Immunohistochemical evaluation of surfactant proteins and lymphocyte phenotypes in the lungs of cattle with natural tuberculosis

The aim of the present study was to evaluate the immunohistochemical expression of pulmonary surfactant proteins (SP-A, SP-B, SP-C) and lymphocytic phenotypes in the lungs of 12 cattle with natural tuberculosis. Grossly, the disease-affected cattle revealed numerous granulomas in the lung lobes. Histopathological examination found multiple lung granulomas with typical cellular elements. Type II pneumocytes with adenomatous proliferation around the granulomas were strongly immunopositive for SP-A and SP-B compared to normal type II cells. Clara cells showed also cytoplasmic immunopositivity for these surfactant proteins. Positive immunolabelling for proSP-C was detected exclusively in the normal and proliferative type II pneumocytes, and the reaction was marked in the perinuclear area of the cells. CD3⁺ T and CD79αcy⁺ B lymphocytes were predominantly localized in the fibrotic capsule margin of advanced granulomas, in greater numbers than in the early granulomas. In conclusion, the study found that type II pneumocytes proliferated highly and surrounded the tuberculous granulomas in the lungs, that hyperplastic type II pneumocytes synthesized and secreted larger amounts of surfactant proteins than the normal type II cells, and that SP-A might have played an important role in host defence against the mycobacterial agents. Additionally, the presence of high numbers of CD3⁺ T cells throughout the granulomas confirmed the dominance of a cellular immune response in cattle tuberculosis.     

非水溶性卟啉显色体系中表面活性剂及助络剂作用机理的初步探讨

本文结合ｍｅｓｏ－四－（４－甲氧苯基）卟啉与金属离子的显色反应,对非水溶性卟啉显色体系中非离子型表面活性剂增溶增敏机理和辅助络合剂的催化作用机理进行了探讨,用“氢键增溶模型”、“催化场模型”和“过渡络合物模型”对上述增溶、增敏和助络催化作用分别进行了解释。     

表面活性剂修复重金属污染土壤的研究进展

表面活性剂在污染土壤修复中具有重要作用。介绍了表面活性剂移除土壤中重金属的机理,综述了不同类型表面活性剂修复重金属污染土壤的国内外研究进展,总结了影响表面活性剂修复效果的因素。     

Application of bioactive coatings based on chitosan for artichoke seed protection

Artichoke seeds suffer attacks of various fungi that result in a decreased yield. Coatings based on chitosan were used as an antifungal agent and for enhancing the germination and quality of artichoke seeds. The effect of formulation (chitosan molecular weight, presence or absence of Span 80, pH), and thickness (number of coating layers) on seed germination (G%), fungi activity and vegetative growth were studied. Results indicated significant differences between treatments on seed germination. It was observed that all chitosan treatments reduced the number of type of fungi and increased plant growth. Chitosan with lower Mw gave better results both from microbial and germination point of view. In addition results indicated that treatments including chitosan and TMTD increased significantly G% and plant growth of artichoke seeds and produced a decrease in fungi contamination.     

Surfactant and antioxidant properties of an extract from Chenopodium quinoa Willd seed coats

Chenopodium quinoa Willd (quinoa) has been a source of food for millennia by the Andes region native population. Because of its bitter taste, quinoa seeds are commercialized without their coat for human consumption. Quinoa coats are surfactant sub-products of the quinoa food industry, which have been only characterized to contain triterpene saponins. We postulated that this coat should also contain antioxidant molecules as part of the defense system of the quinoa seed. We found that a quinoa seed coats hydroalcoholic extract, displayed thiol compounds in addition to polyphenols, recognized antioxidants. Accordingly, it inhibited microsomal lipid peroxidation and the loss of microsomal thiol content, both oxidative phenomena promoted by Cu²⁺/ascorbate. Microsomal glutathione S-transferase (GST) is inhibited by reducing agents, which decrease the content of catalytically active disulfide-linked dimers. The effects of this quinoa extract on microsomal GST are consistent with it displaying disulfide reducing properties. The occurrence of thiol compounds in this quinoa extract is discussed in terms of the potential of their antioxidant properties.     

皂角表面活性物质的提取及其对农药的增效作用研究

以皂角为原材料提取植物源表面活性剂TZR,并研究不同用量对药物的增效作用,结果表明,皂角粗提物的最佳提取溶剂为85％乙醇,产出率高达38％。植物源表面活性剂TZR的配方为皂角提取物浸膏20％＋75％乙醇76％＋甲醛2％＋乙二醇2％。田间试验表明,添加TZR3ml／L时,20％杀虫双水剂300倍液药后1－10d对桃蚜防效...     

Adsorption and desorption of monomeric Bt (Bacillus thuringiensis) Cry1Aa toxin on montmorillonite and kaolinite

Genetically modified crops, which produce pesticidal proteins from Bacillus thuringiensis, release the toxins into soils through root exudates and upon decomposition of crop residues. Although the phenomena of gene transfer and emergence of resistance have been well documented, the fate of these toxins in soil has not yet been clearly elucidated. The aim of this study was to elucidate the adsorption and the desorbability of the Cry1Aa Bt insecticidal protein in contact with two sodium-saturated clays: montmorillonite and kaolinite. Because the toxin is released into soil in small quantities, it was assumed that it will be in a monomeric state in solution until it oligomerized on cell membranes. The originality of this study was to focus on the monomeric form of the protein. Specific sample conditions were required to avoid polymerisation. A pH above 6.5 and an ionic strength of at least 150 mM (NaCl) were necessary to keep the protein in solution and in a monomeric state. The adsorption isotherms obtained were of the L-type (low affinity) for both clays and fitted the Langmuir equation. The adsorption maximum of the toxin, calculated by the Langmuir nonlinear regression, decreased with increasing pH from 6.5, which was close to the isoelectric point, to 9. At pH 6.5, the calculated adsorption was 1.7 g g⁻¹ on montmorillonite and 0.04 g g⁻¹ on kaolinite. Desorbability measurements showed that a small fraction of toxin could be desorbed by water (up to 14%) and more by alkaline pH buffers (36 ± 7%), indicating that it was not tightly bound. Numerous surfactants were evaluated and the toxin was found to be easily desorbed from both clays when using zwitterionic and nonionic surfactants such as CHAPS, Triton-X-100, and Tween 20. This finding has important implications for the optimization of detection methods for Bt toxin in soil.     

水相中钯催化Suzuki偶联反应及其在联苯菊酯合成中的应用

[目的]研究水相中钯催化Suzuki偶联反应在联苯菊酯合成中的应用。[方法]选择表面活性剂（Surfactant）代替水溶性膦配体（三苯基膦三间磺酸钠盐,TPPTS）作为添加助剂,进行水相中钯催化合成联苯菊酯中间体（联苯衍生物）的研究。[结果]结果表明,Ionic Surfactant／Pd（OAc）,的催化活性优于TPPTS／Pd（OAc）2。其中阴离子表面活性剂（十二烷基硫酸钠,SDS）的催化活性优于阳离子表面活性剂（十六烷基三甲基溴化铵,CTAB）和非离子表面活性剂（聚乙二醇400,PEG-400）。当水为反应介质、Pd（OAc）2用量为1．0m01％、K2CO3为碱和SDS为添加助剂时,对于4-甲基溴苯与苯硼酸的偶联反应,加热回流反应1h,可以得到98％的收率。当Pa（OAc）2用量进一步降低为0．1mol％,反应时间延长至6h时,收率可达76％。[结论]产品经过。HNMR表征,结构正确,为目的产物4-甲基联苯。     

多环芳烃污染土壤生物联合强化修复研究进展

多环芳烃(polycyclic aromatic hydrocarbons,PAHs)是广泛存在于环境中的一类有毒有机污染物。在PAHs污染土壤修复领域中,运用一些生物化学的方式来强化生物联合修复技术可以有效缩短生物修复的时间,大大提高修复效率,最具发展前景和应用价值。本文主要以植物-微生物、植物-微生物-土壤动物两种生物联合修复方式为对象,结合各自的特点、机理和实例,推断了其修复机制的内在原因,总结了影响土壤中PAHs降解效率的主要因素(包括:PAHs的浓度水平、根系分泌物的种类、外源添加降解菌和土壤动物的数量和种类、菌属或土壤动物之间的种间竞争和部分环境因素等);同时通过综述近年来国内外强化生物联合修复PAHs污染土壤的技术原理、应用成果和存在的一些问题,指出了不同情况下制约PAHs强化降解进程的潜在限制因子(包括:表面活性剂和固定化微生物的添加量、不同表面活性剂的适度混合、载体材料的性质、固定化方式的选取、土壤养分和水分含量等);并强调在进行强化修复的过程中,要注重现场应用和安全性评价,为多环芳烃污染土壤的生物联合强化修复研究提供了理论依据和技术参考。     

生物质热解生物油/柴油乳化燃料的制备与试验

制备了生物油/柴油乳化燃料并在柴油机台架上进行了试验.试验用生物油是在流化床反应器上对玉米秸秆粉进行热解试验获得的.将生物油与0号柴油以及适量的乳化剂混合,通过均质机均质,得到生物油/柴油乳化燃料.在ZS1110型柴油机台架上进行两种不同配比的生物油/柴油乳化燃料的发动机台架试验,得出了柴油机燃用生物油/柴油乳化燃料和纯柴油的负荷特性和排放特性曲线,并且对乳化燃料和纯柴油的油耗率和有效热效率进行了对比.研究结果表明:生物油体积分数为15%的生物油/柴油乳化燃料较纯柴油有明显的节油效果,最大节油率可达10%;NO、CO的排放也优于纯柴油的排放.