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Mannose receptor (MR) is a member of pattern-recognition receptors (PRRs), which plays a significant role in immunity responses. Much work on MR has been done in mammals and birds while little in fish. In this report, a MR gene (designated as zfMR) was cloned from zebra fish (Danio rerio), which is an attractive model for the studies of animal diseases. The full-length cDNA of zfMR contains 6248 bp encoding a putative protein of 1428 amino acids. The predicted amino acid sequences showed that zfMR contained a cysteine-rich domain, a single fibronectin type II (FN II) domain, eight C-type lectin-like domains (CTLDs), a transmembrane domain and a short C-terminal cytoplasmic domain, sharing highly conserved structures with MRs from the other species. The MR mRNA could be detected in all examined tissues with highest level in kidney. The temporal expression patterns of MR, IL-1β and TNF-α mRNAs were analyzed in the liver, spleen, kidney and intestine post of infection with Aeromonas sobria. By immunohistochemistry assay, slight enhancement of MR protein was also observed in the spleen and intestine of the infected zebra fish. The established zebra fish-A. sobria infection model will be valuable for elucidating the role of MR in fish immune responses to infection.  相似文献   
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Different types of anxiety disorders have become the number one mental health issue in developed countries. The search for new, safer and effective drug-like molecules among naturally derived substances faces two difficulties: an efficient method of isolation compounds with a high-purity and high-throughput animal model for activity assay. Thus, the aim of the present study was to isolate by liquid–liquid chromatography high-purity rare coumarins from the fruits of Seseli devenyense Simonk. and evaluate their anxiolytic effect (defined as reversed thimotaxis) using a 5-days post-fertilization (dpf) Danio rerio larvae model. Liquid–liquid chromatography enabled the isolation of one simple hydroxycoumarin (devenyol) and four pyranocoumarins (cis-khellactone, d-laserpitin, isolaserpitin and octanoyllomatin). The anxiolytic effect was defined as a decrease in the time spent in the boundaries of the living space (also described as reversed thigmotaxis). Our results show that all isolated courmarins exerted a significant influence on the anxiety behavior (anxiolytic activity) in the zebrafish larvae model. According to our knowledge, this is the first report of anxiolytic activity of pyranocoumarins and devenyol.  相似文献   
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Prerequisite to any biological laboratory assay employing living animals is consideration about its necessity, feasibility, ethics and the potential harm caused during an experiment. The imperative of these thoughts has led to the formulation of the 3R-principle, which today is a pivotal scientific standard of animal experimentation worldwide. The rising amount of laboratory investigations utilizing living animals throughout the last decades, either for regulatory concerns or for basic science, demands the development of alternative methods in accordance with 3R to help reduce experiments in mammals. This demand has resulted in investigation of additional vertebrate species displaying favourable biological properties. One prominent species among these is the zebrafish (Danio rerio), as these small laboratory ray-finned fish are well established in science today and feature outstanding biological characteristics. In this review, we highlight the advantages and general prerequisites of zebrafish embryos and larvae before free-feeding stages for toxicological testing, with a particular focus on cardio-, neuro, hepato- and nephrotoxicity. Furthermore, we discuss toxicokinetics, current advances in utilizing zebrafish for organ toxicity testing and highlight how advanced laboratory methods (such as automation, advanced imaging and genetic techniques) can refine future toxicological studies in this species.  相似文献   
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现行的废水监测仅能对有限的几个理化指标进行在线监控,无法全面反映废水中有毒污染物的排放情况。本文引进用于水源安全预警的生物安全预警系统,并通过试验将其对印染废水出水复合污染物的监控进行了分析。结果表明:1.该印染废水进水含多种有毒物质,有较强生物毒性,而经处理的出水正常情况下无明显急性生物毒性。2.当出水中含有一定量有毒物质时,系统能进行及时有效的预警;3.系统可实现较长时间的在线监测需要,能很好地反映企业有毒废水的排放情况。  相似文献   
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研究翼茎羊耳菊(Inula pterocaula)根部三萜类化学成分,阐明其药效物质基础.采用Sephadex LH-20凝胶材料、Rp-18反向材料和硅胶进行化合物分离,利用现代光谱技术和理化性质鉴定化合物结构.并从中分离得到12个三萜类化学成分,分别鉴定为β-香树脂醇(1)、赤藓糖醇(2)、乌苏酸(3)、齐墩果酸(4)、2β,3β,23α-三羟基-28-齐墩果酸(5)、齐墩果酸-28-O-β-D-吡喃葡萄糖苷(6)、齐墩果酸-3-O-β-D-吡喃葡萄糖苷(7)、齐墩果酸-3-O-(β-D-吡喃葡萄糖)-28-O-β-D-吡喃葡萄糖苷(8)、2β-羟基-3-O-β-D-吡喃葡萄糖-23,28-二齐墩果酸(9)、3-O-β-吡喃葡萄糖-(1→4)-β-D-吡喃葡萄糖醛基-23-羟基-齐墩果酸-28-O-β-D-吡喃葡萄糖苷(10)、3-O-β-D-吡喃葡萄糖-19α-羟基-乌苏酸-28-O-β-D-吡喃葡萄糖苷(11),3-O-α-L-吡喃阿拉伯糖-20,19,24-三羟基乌苏酸(12).以上化合物为首次从该植物中得到.该研究结果可为翼茎羊耳菊的进一步研究提供依据.  相似文献   
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利用斑马鱼作为模式生物,进行一系列的实验研究,尤其在胚胎发育、基因表达、药物筛选和疾病模型方面有其独特的优势。但它被应用于辐射效应修饰剂的研究时间较短,已有的文献显示发展前景良好。本工作就近些年以斑马鱼为模式生物研究的辐射效应修饰剂进行概述,主要涉及如氨磷汀、DF-1、AG1478、Flavopiridol和一些DNA损伤修复蛋白。  相似文献   
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蔡翔  王捷  王颖 《农药》2005,44(6):271-273
采用斑马鱼胚胎发育技术,通过对斑马鱼急性毒性及胚胎时期的鱼卵进行染毒来观测孵化率、畸形率及死亡率,由此评价氟吗啉对斑马鱼胚胎-幼体发育的影响。试验结果表明,氟吗啉对斑马鱼胚胎及成鱼这一段时期的影响较小,根据国家环保局对水生生物的毒性划分标准,氟吗啉的毒性为“低级毒”。  相似文献   
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目的 研究绿茶提取物(green tea extract,GTE)、乌龙茶提取物(oolong tea extract,OTE)和红茶提取物(black tea extract,BTE)对2,4-二氯苯氧乙酸(2,4-Dichlorophenoxyacetic acid,2,4-D)导致的斑马鱼胚胎发育毒害的影响。方法 用50 mg/L 2,4-D分别联合6.25、12.50和25.00 mg/L GTE,6.25、12.50和25.00 mg/L OTE以及50、100和150 mg/L BTE处理斑马鱼胚胎至96 hpf(hours post fertilization),体视显微镜观察斑马鱼胚胎发育并统计孵化率、死亡率、畸形率,测定斑马鱼心跳次数、体长、卵黄和心包面积。结果 各处理组斑马鱼胚胎孵化正常。除2,4-D + BTE处理组随BTE浓度提高死亡率升高,其他处理组没有发生显著死亡。GTE降低2,4-D导致的斑马鱼胚胎畸变率,提高2,4-D导致的心跳下降和体长缩短,缩小2,4-D导致的卵黄和心包面积;相反,BTE加重2,4-D导致的斑马鱼胚胎形态发育毒害;而OTE对2,4-D导致的斑马鱼胚胎发育毒害无明显影响。结论 GTE、OTE和BTE对2,4-D导致的斑马鱼胚胎发育毒害分别具有拮抗作用、无作用和协同作用。  相似文献   
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