Trypanocidal Activity of Marine Natural Products

Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion.     

海洋青霉菌抗真菌活性物质高产菌株的诱变选育

采用紫外线(UV)、激光(Laser)、亚硝基胍(NTG)复合诱变HN89青霉菌后，再用HN89菌株的次生代谢产物(HN89A)对复合诱变菌株进行了自我抗性的选育．结果表明，与出发菌相比，菌株经诱变后相对效价显提高．自我抗性诱变结果表明：在67株经复合诱变的抗性菌株中，其抗真菌活性物质相对效价高于出发菌株的正变株有60株，正变率达到90％。其中相对效价提高50％以上的菌株为2l株，占所筛选菌株总数的31％；效价提高100％以上的菌株为9株，占13％，其中突变株HN89-68活性物质的相对效价可提高到286％。活性物质效价提高幅度与其自身产量提高幅度存在一定的正相关。诱变高产菌株遗传稳定性好．     

大型低速船用柴油机燃油共轨系统建模

以瓦锡兰Sulzer 7RT—flex60C型船用柴油机为研究对象,首先介绍了燃油共轨系统的组成,分析了燃油共轨系统的特性,然后利用流体力学原理构建了燃油共轨系统各个模块的数学模型,最后采用MATLAB／Simulink软件进行仿真计算．仿真结果与船用柴油机台架数据误差符合要求,具有一定的有效性和准确性．     

海洋立管气液两相流动模拟研究进展

随着海洋石油工业的发展,从20世纪70年代的浅海立管到21世纪的深海立管,海洋管道发展了多种新的形式,如悬链线立管、S形立管等。对于各种混输立管系统,严重段塞流等不稳定流动会造成设备损坏,严重影响安全生产。因此,实现立管流动的准确模拟,通过合理设计和科学运行控制、消除严重段塞流,具有重要意义。综述了国内外海洋混输立管流动模拟的研究成果,包括L形立管和柔性立管的实验研究、模型模拟及软件模拟的主要进展。指出了当前研究中存在的问题及未来的研究方向,可为进一步开展立管流动模拟研究提供参考。     

Reinventing residual reserves in the sea: are we favouring ease of establishment over need for protection?

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Site fidelity,survival and conservation options for the threatened flapper skate (Dipturus cf. intermedia)

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Evaluation of apparent digestibility coefficients of individual feed ingredients in spotted rose snapper Lutjanus guttatus (Steindachner, 1869)

Apparent digestibility coefficients (ADCs) for dry matter, crude protein, energy and essential amino acids for five commonly used feed ingredients were determined for juvenile spotted rose snapper Lutjanus guttatus (average body weight 90.6 g). ADCs were determined using the stripping technique to collect faeces after fish were fed a reference diet and test diets composed of 700 g kg^?1 reference diet and 300 g kg^?1 test ingredient. Chromic oxide (Cr₂O₃) was used as an inert indicator. Ingredients tested included sardine fishmeal (FM), canola meal (CM), tuna by‐products meal (TBM), poultry by‐product meal pet grade (PBM‐PG) and solvent‐extracted soybean meal (SBM). In general, all ingredients showed high digestibility values for all essential amino acids, although differences were detected among ingredients. ADC values for dry matter, protein and energy ranged 77.0–80.4%, 84.3–82.5% and 89–88.8%, respectively, for marine ingredient and land‐based animal protein sources, and 75.0–74.2%, 81.5–80.9% and 87.4–86.8%, respectively, for the plant‐based protein source. SBM, TBM and PBM‐PG should be further evaluated in feeding trials as partial FM replacements in rose snapper L. guttatus diets. Knowledge of ADC values for these ingredients will allow feed producers to develop nutritionally balanced, low‐cost feed formulations for this species.     

天津港口疏浚淤泥悬浮物对海洋动物的急性毒性效应

研究了不同浓度的悬浮物对鲈鱼和梭鱼幼体的毒性效应。实验结果表明:疏浚淤泥悬浮相对其效应明显。21℃和24℃试验水温时,悬浮物对鲈鱼幼苗的急性毒性实验结果分别为:96hLC50为1 711.2mg/L、1 052.8mg/L;安全浓度分别为:171.12、105.28mg/L;悬浮物对梭鱼幼苗的急性毒性实验结果分别为:96h LC50为453.6、168.1mg/L;安全浓度分别为:45.36、16.81mg/L。随温度、悬浮物浓度的升高,毒性效应呈增强趋势。     

影响我国海洋生态安全的因素及对策

海洋生态安全对于海洋经济持续、健康、稳定发展具有重要作用。人类不合理的开发、利用海洋资源,使海洋生态系统不断遭到破坏,制约海洋经济的可持续发展。在海洋经济飞速发展的今天,我国海洋生态安全总体形势严峻,本文在分析影响海洋生态安全因素的基础上,从加强海洋生态道德建设、加强海洋环境监测、建立防灾减灾体系、国际协作等七个方面提出加强海洋生态保护、保障海洋生态系统健康稳定发展的对策。     

海洋环境因子对日本海太平洋褶柔鱼渔场时空分布的影响

根据2010—2013年11—12月日本海太平洋褶柔鱼(Todarodes pacificus)的渔获生产数据,并结合遥感获取的海洋环境数据,利用渔获量重心法、地统计插值和数理统计方法,分析了太平洋褶柔鱼的资源丰度与渔获量重心的时空变化及其与主要环境因子(海表温度、叶绿素浓度、海流)之间的关系。研究表明,渔场重心每年稍有差异,经度重心集中在132°20′E附近;纬度重心集中在36°30′N和37°30′N两个位置附近。GAM模型显示,日本海太平洋褶柔鱼渔场的最适海表温度为16~18℃;最适叶绿素a浓度为0.37~0.45 mg/m3。海洋环境与单位捕捞努力渔获量(CPUE)的回归方程的显著性检验表明,除了叶绿素a浓度呈一般显著外,海表温度和空间因子在CPUE上的回归均极显著(P0.01),符合统计意义。4年间渔场的适宜环境范围有所差异,推断主要是日本海海域对马暖流、东朝鲜暖流与里曼寒流相互交汇的强弱作用力引起的,也有不同年份季风的强弱不同以及全球气候变化的因素存在。每一年的渔场海洋环境因子稍有差别,对其资源量的影响巨大。