In vitro antioxidant synergism and antagonism between food extracts can lead to similar activities in H2O2‐induced cell death,caspase‐3 and MMP‐2 activities in H9c2 cells

BACKGROUND: The cardio‐health‐promoting activity of some foods may be due to their specific antioxidant content. The antioxidant activity of a mixture of plant extracts has been shown to differ from the activity of the individual extracts. As a result, the activity of the mixture can be described as synergistic, antagonistic or additive. This in vitro study evaluated the relationship between the in vitro antioxidant capacity of mixtures and their bioactivity when cardiomyocytes (H9c2) were challenged with H₂O₂. RESULTS: A mixture of raspberry and adzuki bean extracts produced a synergistic response and a mixture of broccoli and soybean extracts produced an antagonistic response in chemical‐based antioxidant assays. When these extracts were tested in cell cultures, individually and in mixtures, the mixture of raspberry and adzuki bean protected the cardiomyocytes from H₂O₂‐induced cell damage significantly better than the individual extracts. Conversely, the mixture of broccoli and soybean extracts was less effective in protecting H9c2 cells. The synergistic and antagonistic effects of the mixtures in protecting cell damage were brought about by enhanced or reduced ability in attenuating caspase‐3 and matrix metalloproteinase‐2 activities elevated by H₂O₂. CONCLUSION: Food mixtures with synergistic antioxidant activity and protective property against reactive oxygen species‐induced cell death can potentially be incorporated into novel functional foods or beverages with optimum health benefit. The antagonistic effect of food mixtures can be a health concern and thus should be avoided. Copyright © 2012 Society of Chemical Industry     

葡萄采后病害生防制剂用拮抗酵母的筛选

本研究通过对比5种拮抗酵母在抑制葡萄采后病害中的效果,以及在正常葡萄表面的生长适应性,从中筛选出适合开发成牛防制剂的种类.结果表明:罗伦隐球酵母和季也蒙假丝酵母的抑菌效果较好,从生长适应性方面比较,季也蒙假丝酵母最适合开发成生防制剂.     

Intracerebroventricular ethanol-induced conditioned place preferences are prevented by fluphenazine infusions into the nucleus accumbens of rats.

The rewarding properties of centrally administered ethanol (EtOH) were examined using a conditioned place preference (CPP) test. Male rats subjected to bilateral intracerebroventricular (icv) infusions of EtOH (0-240 nmol) produced a dose-dependent preference for the drug-paired environment that was potentiated by concurrent intravenous (iv) administration of heroin (0.025 mg/kg). The role of mesolimbic dopamine (DA) pathways in the development of EtOH reward was then examined by challenging EtOH-treated rats with bilateral intra-accumbens shell applications of a DA receptor antagonist. Fluphenazine (10 or 50 μg/side), infused immediately prior to daily place conditioning trials, was found to reliably attenuate the development of CPPs produced by icv EtOH administration. When fluphenazine was administered into the nucleus accumbens shell prior to the final test trial only (i.e., in already conditioned rats), intra-accumbens shell DA receptor blockade was found to prevent the expression of CPPs produced by icv EtOH. In summary, rats form reliable learned preferences for EtOH-paired locations (CPPs) that are potentiated by iv heroin and whose acquisition and expression rely on intact DA functionality within the nucleus accumbens. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

金属化合物在PP膨胀阻燃体系中的研究

探讨了几种金属化合物对PP膨胀阻燃体系的影响,通过锥形量热仪分析了体系的阻燃性,SEM观察燃烧后材料的成炭情况。结果表明,ZB、ZEO、MgO能起到协效作用,成炭较好,而CuCl不但不能起到协效作用反而破坏了炭层的质量,呈对抗性。     

现代烟火技术的新进展

本文叙述了烟火技术的内涵及其应用与发展，简介了其在高科技战争中的作用地位以及现代烟火技术在国外的发展状况。     

Neotyphodium coenophialum Mycelial Protein and Herbage Mass Effects on Ergot Alkaloid Concentration in Tall Fescue

Livestock grazing endophyte-infected tall fescue (Festuca arundinacea Schreb.) pastures often suffer from ergot poisoning. The endophyte,Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon, and Hanlin, comb. nov., also provides drought-tolerant, insect-resistant, and disease-resistant qualities to the plant. Therefore, producers are faced with a biological dilemma of risking loss of pasture by using endophyte-free tall fescue pasture or animal losses with endophyte-infected tall fescue pasture. One potential solution is to breed endophyte-infected tall fescue with lower levels of alkaloids. However, breeding could select for plants that are antagonistic to the endophyte, resulting in reduced plant vigor as a consequence of disruption of the mutualistic association between the organisms. The objectives of this study were to determine the relationship between plant mass and endophyte mycelial proteins versus ergot alkaloid concentration. To examine the endophyte effect on mycelial mass, tissue culture regenerants from tall fescue genotype PDN2 were infected with endophyte isolates EDN11, EDN12, and EDN2 to eliminate confounding effects of multiple plant genotypes. Crosses with PDN11 as the maternal parent and plant genotypes DN2, DN12, and DN15 as paternal parents were used to produce a population of different plant genotypes, all containing the same endophyte. Fungal mycelial protein was extracted from lyophilized tall fescue leaf sheath tissue and immunochemically quantified with monoclonal antibodies specific toN. coenophialum proteins. Ergot alkaloid concentration was also immunochemically measured. Quantities of mycelial protein and ergot alkaloids were calculated by regressing experimental values against standards of each. There was no correlation between herbage mass and alkaloid concentration or fungal protein quantity and alkaloid concentration when different fungal isolates were inserted into the same plant genotype. Coefficients of determination (r ²) were low (0.31 and 0.17) between leaf sheath and leaf blade alkaloid concentrations and endophyte protein when different plant genotypes contained the same endophyte isolate. Likewise,r ² values were low between leaf sheath and leaf blade alkaloid concentrations and herbage mass. These data suggest that little or no antagonism occurred to the endophyte among plants low in alkaloid concentration.     

2,2′-OXO-1,1′-azobenzene: Selective toxicity of rye (Secale cereale L.) allelochemicals to weed and crop species: II

Three allelochemicals from rye or its breakdown products were evaluated for activity on garden cress (Lepidum sativum L.), barnyardgrass [Echinochloa crus-galli (L.) Beauv.], cucumber (Cucumis sativus L.), and snap bean (Phaseolus vulgaris L.). 2,4-Dihydroxy-1,4(2H)-benzoxazin-3-one (DIBOA), 2(3H)-benzoxazolinone (BOA), and 2,2-oxo-1,1-azobenzene (AZOB) were all applied singly at 50, 100, and 200 ppm and in two- and three-way combinations each at 50 and 100 ppm. AZOB at 100 and 200 ppm produced 38–49% more inhibition than DIBOA, while combinations of BOA/ DIBOA, which contained AZOB at 100 ppm had 54–90% more inhibition when compared to DIBOA/BOA combinations. All combinations were slightly antagonistic to barnyardgrass, while several combinations caused a synergistic response to garden cress germination and growth. Cucumbers and snap beans exhibited both types of responses, depending on the allelochemical combination and application rate. The plant-produced benzoxazinones were more inhibitory to crops than weeds. Therefore, improved herbicidal selectivity would be expected if there were rapid transformation of the benzoxazinones to the microbially produced AZOB.     

Statistical analysis of the joint inhibitory action of similar compounds

A statistical model is presented that characterizes the joint action of similar compounds when the response variable is continuous. The model allows for antagonistic and synergistic as well as similar joint (additive) action of compounds. It also allows for differential potencies in the compounds. A method of statistical analysis using nonlinear regression analysis is presented along with sample SAS code for carrying it out. An efficient experimental design is given in the form of a set of mixture combinations. Two generalizations of the model are discussed. An example is presented relating the joint action of ferulic and vanillic acids to the growth of cucumber seedlings.Paper No. 11878 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, North Carolina 27695-7601. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Research Service of the product named, nor criticism of similar ones not mentioned. This research was partially supported by US-Spain Joint Committee for Scientific and Technological Cooperation project CCA-8309/166.     

复杂电磁环境下雷达兵心理对抗问题探析

雷达兵心理对抗是雷达兵信息作战的一种基本样式.在复杂电磁环境下,实施雷达兵心理对抗的好与坏,对雷达兵信息作战的成败有着重要的影响.根据雷达兵心理对抗的主要任务和基本特点,探究和提出了提高综合素质、增强信息监控、适时心理疏导、优化心理环境4个方面的心理防御措施及先发制人、强化宣传、组织反击、隐形干扰4个方面的心理反击措施.     

大鼠出生前接触苯妥英和褪黑素对仔代反射功能发育及自发运动的影响

目的 探讨苯妥英(DPH) 神经发育毒性与胚胎脑组织中自由基产生和氧化应激反应的关系。 方法 Wistar 孕鼠于妊娠d 11 ~ 14 经0, 100,200 mg·kg^-1 DPH 或合并40 mg·kg^-1褪黑素(MT) 染毒处理, 研究MT 对DPH 的仔代反射功能发育及自发运动损害作用的拮抗效应。 结果 孕鼠在染毒期及染毒后增重下降, 仔代体重减轻, 哺乳期死亡率增高;DPH 染毒仔鼠的转身运动增多, 空中翻正反射及游泳能力发育延迟, 成年后行走次数、站立次数、刻板动作等自发活动增多, 旋转手比率增多, 对阿朴吗啡“激发”反应性增强。MT 和DPH 合并处理可明显拮抗上述DPH 仔鼠的行为异常。 结论 氧化性损伤在DPH 神经发育毒性发生中发挥重要作用, 而MT 可拮抗其毒性作用。