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以大学生创新训练项目为契机,依托国家级生物制药实验教学示范中心平台,围绕"双靶点抗肿瘤疫苗研制"项目指导大学生进行相关理论知识的学习、科研思路的设计,并完成实验操作、数据整理、专利申请和论文写作等训练。初步选择鼠源粒细胞巨噬细胞集落刺激因子(mGM-CSF)和促胃泌素释放肽(GRP)为双靶点,完成了基因工程菌的构建、目标蛋白的制备、细胞培养、动物肿瘤模型的建立、肿瘤疫苗药效初步分析与探索。通过指导学生申请专利、发表文章、参加药苑论坛、挑战杯等各类比赛完成对学生的训练,提升其自主设计实验、自主完成实验、自主管理实验等综合能力。 相似文献
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The escalating demand for fipronil by the increasing insects’ resistance to synthetic pyrethroids placed a burden on aquatic vertebrates. Although awareness regarding the toxicity of fipronil to fish is arising, the integral alteration caused by fipronil remains unexplored. Here, we investigated on the development toxicity of fipronil and the metabolic physiology perturbation at 120 h post fertilization through GC–MS metabolomics on zebrafish embryo. We observed that fipronil dose-dependently induced malformations including uninflated swim bladder and bent spine. Further, the “omic” technique hit 26 differential metabolites after exposure to fipronil and five significant signaling pathways. We speculated that changes in primary bile acid synthesis pathway and the content of saturated fatty acid in the chemical-related group indicated the liver toxicity. Pathway of Aminoacyl-tRNA biosynthesis changed by fipronil may relate to the macromolecular synthesis. Concurrently, methane metabolism pathway was also identified while the role in zebrafish needs further determination. Overall, this study revealed several new signaling pathways in fipronil-treated zebrafish embryo/larval. 相似文献
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《Vaccine》2016,34(42):5099-5106
Salmonella-induced gastroenteritis causes massive morbidity and mortality in both adults and children of developing countries. However, it is difficult to study the mode of infection and vaccine efficacy due to inadequacies of current animal models. For this reason, we have explored using zebrafish as an improved model for non-typhoidal Salmonella (NTS) infection, including Salmonella enterica Typhimurium, Salmonella enterica Enteritidis and Salmonella enterica Weltevreden. In this study, we found that after infection of zebrafish with NTS, severe diarrhea like symptoms were observed and NTS significantly colonized the zebrafish intestine without any manipulation of the normal intestinal microbiota of the fish. Furthermore, these strains can colonize for longer than 72 h and induce severe inflammation in the intestine, which may induce fish death. We also found that infected fish can transmit the pathogen into naïve fish. Moreover, we have established that zebrafish is an excellent model for vaccine study. Successive triple bath vaccination with heat-killed single serotype S. Typhimurium and S. Enteritidis immunogen induced protective efficacy against a high dose (108 CFU/ml) of infection with these pathogens. This study provides a natural infection model for the study of NTS infection, transmission and vaccine efficacy. 相似文献
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An-feng TAO Zheng-hao XU Cheng-hao WU Yi WANG Wei-wei HOU Shi-hong ZHANG Zhong CHEN 《浙江大学学报(医学版)》2015,44(3):315
目的观察比较不同脉冲波形的低频率电刺激对海马电点燃癫痫模型小鼠的作用差异。方法采用电点燃刺激法建立小鼠癫痫模型, 观察正弦波、单相方波、双相方波低频率电刺激对模型小鼠癫痫行为发作及后放电持续时间的影响, 并比较不同时间点给予正弦波低频率电刺激的抗癫痫作用。结果与对照组比较, 正弦波低频率电刺激30 s能降低小鼠海马电点燃癫痫发作等级(2.85 ± 0.27 vs 4.75 ±0.12, P < 0.05)、减少大发作概率(53.6% vs 96.5%, P < 0.01) 和缩短后放电持续时间[(16.22 ± 1.69) s vs (30.29 ± 1.12) s, P < 0.01], 而单相方波和双相方波低频率电刺激30 s没有明显的抗癫痫作用。常用的单相方波低频率电刺激15 min能降低小鼠海马电点燃发作等级(3.58 ± 0.16, P < 0.05)、减少大发作概率(66.7%, P < 0.01);但对海马后放电持续时间及大发作持续时间无影响(均 P>0.05)。此外, 电点燃刺激前预先给予或结束后3 s内给予正弦波低频率电刺激具有明显的抗癫痫作用( P < 0.05或 P < 0.01), 而电点燃刺激结束10 s给予正弦波低频率电刺激则无上述抗癫痫作用。 结论低频率电刺激抗癫痫作用受波形参数的影响, 其中正弦波低频率电刺激能有效抑制小鼠海马电点燃癫痫的发作。 相似文献
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Harit Kapoor Kush Raj Lohani Tommy H. Lee Devendra K. Agrawal Sumeet K. Mittal 《CTS Clinical and Translational Science》2015,8(6):841-847
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis. 相似文献
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Matilde Bongio Jeroen J. J. P. van den Beucken Sander C. G. Leeuwenburgh John A. Jansen 《Journal of tissue engineering and regenerative medicine》2015,9(3):191-209
Injectable bone substitutes (IBSs) represent an attractive class of ready‐to‐use biomaterials, both ceramic‐ and polymer‐based, as they offer the potential benefit of minimally invasive surgery and optimal defect filling. Although in vitro assessments are the first step in the process of development, the safety and efficacy of an IBS strongly depend on validated preclinical research prior to clinical trials. However, the selection of a suitable preclinical model for performance evaluation of an IBS remains a challenge, as no gold standard exists to define the best animal model. In order to succeed in this attempt, we identified three stages of development, including (a) proof‐of‐principle, (b) predictive validity and (c) general scientific legitimacy, and the respective criteria that should be applied for such selection. The second part of this review provides an overview of commonly used animals for IBSs. Specifically, scientific papers published between January 1996 and March 2012 were retrieved that report the use of preclinical models for the evaluation of IBSs in situations requiring bone healing and bone augmentation. This review is meant not only to describe the currently available preclinical models for IBS application, but also to address critical considerations of such multi‐factorial evaluation models (including animal species, strain, age, anatomical site, defect size and type of bone), which can be indicative but in most cases edge away from the human reality. Consequently, the ultimate goal is to guide researchers toward a more careful and meaningful interpretation of the results of experiments using animal models and their clinical applications. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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目的 探讨深静脉血栓形成(deep venous thrombosis,DVT)动物模型建立的要素,提高造模成功率,为深静脉血栓形成的研究提供规范化的动物模型。方法 以中国知网、万方数据库、维普数据库、PubMed数据库收录的期刊文献为资料来源,以动物模型的应用、实验动物种类、造模的方法、检测指标为分类依据建立数据库,使用SPSS Modeler 18.0、SPSS Statistics 22.0软件对导入的数据进行关联规则分析和因子分析。结果 对纳入的246篇符合标准的文献数据进行分析,造模主要用于DVT机制研究,实验动物使用雄性C57BL/6小鼠最多,通常运用下腔静脉结扎法造模,检测最多的指标为血栓质量/长度。通过关联规则及因子分析得出4组关联强度高的检测指标,并提取10个公因子。结论 结合现代信息技术,将实验动物模型的关键指标数据进行更深层次的整合与分析,有助于建立更加科学、标准化的动物模型,对进一步探究DVT的发病机制及治疗方法具有重要意义。 相似文献