关于转化医学在生化教学中的几点对策与思考

转化医学(translational medicine),其核心是要将生物医学基础研究成果迅速有效的转化为可在临床医学实际应用的理论、技术、方法和药物。作者作为生物化学与分子生物学教师,在转化医学大背景下在生化教学改革方面进行了一些尝试,提出了转化医学在生化教学中的几点对策与思考,以供大家探讨。     

转化医学信息

转化医学作为医学研究的一个分支,从其概念的提出到现在十多年间发展迅速,广泛引起了世界各国学者的关注和重视。转化医学的核心是将医学生物学基础研究成果迅速有效地转化为可在临床实践中应用的理论、技术、方法和药物,并在实验室与病房之间架起一条快速通道,实现基础研究与,临床研究的双向转化,是沟通基础医学与临床医学的桥梁,     

转化医学研究中生命伦理学辩护的现况分析与前瞻思考

转化医学作为一门新兴学科,运用多学科交叉策略来推动医学发展,从临床实践中发现问题,将其凝练成科学问题进行基础医学研究,再将研究成果应用到疾病诊断、治疗和预防过程中,使其真正发挥作用,是一个从基础医学到临床应用的双向进程。转化医学已逐步融入各个学科,并在干细胞研究、生物标志物、细胞信号转导、药物及器具研发及个体化医学等各个领域发挥重要作用。随着转化医学研究深入,一些临床试验势必对人体存在一定伤害和潜在危险,存在各种伦理问题。虽说科学研究与伦理道德是一对相互冲击的矛盾,但两者在总体上又是一致的,共同决定着社会前进步伐。科研的重大进步必然会对伦理道德提出更高要求,而伦理道德的高标准又规范、引导、促进科学研究朝着正确方向迈进,两者相辅相成。鉴于伦理辩护对于转化医学研究强有力的支撑,建议在转化医学研究中能进一步完善伦理监管体系,发挥机构伦理委员会的功效,持续加大伦理培训的力度,强化研究人员的伦理道德修养,从而为转化医学的发展夯实人文基础。     

酿酒酵母遗传缺陷型菌株化学转化方法研究

目的:通过改善转化条件,提高缺陷型酿酒酵母DNA转化效率。方法:以醋酸锂化学转化法为基础,以酿酒酵母菌株fab1::KAN作为遗传转化受体,以敲除MZM1基因为转化目的,对影响遗传缺陷型菌株转化效率的参数(醋酸锂前处理、热激时间及转化后复苏时间)进行优化,确定适合缺陷型酵母DNA转化的最佳方法。结果:不同时间(30 min,60 min和120 min)醋酸锂的前处理均可以提高其转化效率,热激前使用醋酸锂处理酵母30 min转化效率最高;热激10 min是转化效率由高到低的转折点,30 min热激明显降低了转化效率;YPD培养基用于转化后酵母的复苏,随培养时间(30 min,60 min和120 min)的延长,酵母转化效率逐步增加,120 min作为热敏性菌株转化后的复苏时间较佳。结论:与野生型菌株类似,通过转化条件的优化,遗传缺陷型菌株的转化效率也可以满足大多数试验要求。     

人乳头瘤病毒16型亚基因DNA体外转化功能的细胞学研究

利用HZIP16和HZIP16K(见材料和方法)质粒,将人乳头瘤病毒16型(HPV-16)的全早期区基因及其开放读码框架(ORF)E6-E7分别转入ψ2细胞,所产生的重组病毒能诱导NIH3T3细胞发生转化。转化细胞具有恶性细胞的生物学和形态学特征,可在0.3％软琼脂中形成集落,可使裸鼠致瘤。Southern blot证明,HPV-16 E6-E7 ORFs序列以整合形式存在于转化细胞和裸鼠肿瘤细胞DNA中,表明HPV-16 DNA具有体外诱导NIH3T3细胞恶性转化的作用,E6-E7 ORFs是诱导细胞转化的关键基因。     

犬2型腺病毒E1转化细胞系的特性研究

对筛选到的一株CAV—2 E1转化细胞(DK／E1)进行了初步的特性研究。以DK细胞为对照,观察到转化细胞的形态与DK细胞有明显区别,细胞变长,易聚集生长。通过测定DK及DK／E1细胞分别在2％、5％和10％牛血清培养基中的生长曲线,结果发现DK／E1细胞的生长速度比DK细胞快。用蚀斑和TCID50测定了病毒在DK和DK／E1细胞上的病毒滴度,结果表明DK／E1细胞产生的病毒蚀斑比DK细胞的大,TCID50测得的病毒滴度比DK细胞产生的病毒滴度高。CAV—2全基因组DNA对DK／E1细胞和DK细胞的转染试验结果表明,5μg和10μg的CAV—2 DNA转染的DK／E1细胞,分别在转染后第14天和第11天均出现了典型的腺病毒细胞病变,而相同量CAV—2 DNA转染的DK细胞未出现病变,说明DK／E1细胞有助于CAV—2 DNA的复制和病毒粒子的包装。在DK／E1细胞内的重组试验表明,DK／E1细胞也有利于重组病毒的产生。以上转化特性在DK／E1细胞传至80代时仍保持不变,说明本试验获得了一株CALV—2 E1基因的转化细胞系。     

肺泡Ⅱ型细胞表皮生长因子和转化生长因子α、β1及其受体表达的研究

分离培养成年大鼠的肺泡Ⅱ型细胞,通过斑点杂交、原位杂交和免疫组织化学染色,研究肺泡Ⅱ型细胞内表皮生长因子（EGF）、转化生长因子α和β1（TGFα、TGFβ1）及其受体基因的表达。结果显示肺泡Ⅱ型细胞可表达EGF、TGFα和TGFβ1,也可表达相应的EGF受体（EGFR）、TGFβ受体Ⅰ型和Ⅱ型（TβRⅠ、TβRⅡ）。表明肺泡Ⅱ型细胞是合成和分泌EGF、TGFα和TGFβ1的细胞之一;细胞凭借其EGFR、TβR的存在,其增殖与分化可能受EGF、TGFα和TGFβ1的旁分泌和自分泌两种途径调控。     

D型氨基酸氧化酶活性对于D-硝基精氨酸手性转化的影响

D-硝基精氨酸(D-NNA)可在大鼠体内发生手性转化生成其L型异构体,即L-NNA,后者可抑制一氧化氮合酶活性,减少一氧化氮生成,升高动脉血压.研究了D型氨基酸氧化酶(DAAO)在D-NNA手性转化中的作用及DAAO对不同(包括已报道在体内可发生手型转化的)D型氨基酸的选择活性.体内实验显示,DAAO的选择性抑制剂苯甲酸钠(400mg/kg)或肌酐(400mg/kg)均可在不同程度上抑制D-NNA升压作用,进一步研究发现,肾脏或肝脏DAAO酶液在外加DAAO后可提高D-NNA的手性转化约2倍,表明DAAO对于D-NNA在体内的手性转化是必需的.DAAO酶液对可在体内发生手性转化且转化率相似(30%～50%)的D型氨基酸(D-Phe,D-Leu和D-NNA)的选择性表现出显著差异(Kcat/Km相差可达约15倍左右),这从另一方面表明体内D-硝基精氨酸氧化是其发生手性转化的前提条件但非决定因素.     

肺泡型细胞内表皮生长因子和转化生长因子α、β_1及其受体基因表达的研究

分离培养成年大鼠的肺泡 型细胞 ,通过斑点杂交、原位杂交和免疫组织化学染色 ,研究肺泡 型细胞内表皮生长因子 (EGF)、转化生长因子 α和 β1 (TGFα、TGFβ1 )及其受体基因的表达。结果显示肺泡 型细胞可表达 EGF、TGFα和TGFβ1 ,也可表达相应的 EGF受体 (EGFR)、TGFβ受体 型和 型 (TβR 、TβR )。表明肺泡 型细胞是合成和分泌 EGF、TGFα和 TGFβ1 的细胞之一 ;细胞凭借其 EGFR、TβR的存在 ,其增殖与分化可能受 EGF、TGFα和 TGFβ1 的旁分泌和自分泌两种途径调控。     

抗虫基因转化优良籼型保持系D297B的研究

本文报道了用基因枪法将雪花莲外源凝集素基因(gna)转移到优良籼型杂交稻保持系D297B中。通过PCR、Southern blotting和Western blotting等分子检测方法证明,外源基因已整合到受体材料的基因组中并得到表达。蛋白活性测定结果显示转基因在受体中表达的蛋白具有生物活性。潮霉素抗性分析表明外源基因多数是以单位点形式整合并以3∶1方式遗传。另外,PCR证据也说明抗虫基因与选择标记基因基本上是共整合和共遗传的     

Ethical issues in translational research

The translation of biomedical research knowledge to effective clinical treatment is essential to the public good and is a main focus of current health policy. However, recent health policy initiatives intended to foster the translation of basic science into clinical and public health advances must also consider the unique bioethical issues raised by the increased focus on translational research. Safety of study participants and balancing of risk due to treatment with the potential benefits of the research is tantamount. This article synthesizes theory from clinical ethics, operational design, and philosophy to provide a bioethical framework for the health policy of translational research.     

Ethical hurdles for translational research

The notion of translational research has gained considerable currency over the past few years. While such an approach promises great scientific and clinical advances, the penumbra of translational research tends to incorporate prioritizing scientific projects based upon their potential for translation; tight financial connections between sponsors, scientists and clinical investigators; and sometimes research involving biological approaches for which there is little experience determining safety. It is these aspects of translational research that raise some serious ethical challenges. In this report, we examine three specific areas that raise ethical questions: (1) the potential implications of prioritizing research objectives based on the potential for translation; (2) cautions related to moving from bench to bedside (and back again); and (3) unique questions for translational research initiatives in academic medical centers. Based on this examination, it is clear that the financial and ethical costs as well as benefits of taking a translational approach need to be considered. In the meantime, exquisite attention needs to be paid whenever translational research is likely to affect the traditional fiduciary responsibilities of scientists, clinicians and institutions to research subjects, patients and students. Successful mechanisms that might be developed to address any untoward effects should be shared and evaluated.     

Humanized mice in translational biomedical research

The culmination of decades of research on humanized mice is leading to advances in our understanding of human haematopoiesis, innate and adaptive immunity, autoimmunity, infectious diseases, cancer biology and regenerative medicine. In this Review, we discuss the development of these new generations of humanized mice, how they will facilitate translational research in several biomedical disciplines and approaches to overcome the remaining limitations of these models.     

New frontiers in translational research: Touchscreens,open science,and the mouse translational research accelerator platform

Many neurodegenerative and neuropsychiatric diseases and other brain disorders are accompanied by impairments in high-level cognitive functions including memory, attention, motivation, and decision-making. Despite several decades of extensive research, neuroscience is little closer to discovering new treatments. Key impediments include the absence of validated and robust cognitive assessment tools for facilitating translation from animal models to humans. In this review, we describe a state-of-the-art platform poised to overcome these impediments and improve the success of translational research, the Mouse Translational Research Accelerator Platform (MouseTRAP), which is centered on the touchscreen cognitive testing system for rodents. It integrates touchscreen-based tests of high-level cognitive assessment with state-of-the art neurotechnology to record and manipulate molecular and circuit level activity in vivo in animal models during human-relevant cognitive performance. The platform also is integrated with two Open Science platforms designed to facilitate knowledge and data-sharing practices within the rodent touchscreen community, touchscreencognition.org and mousebytes.ca. Touchscreencognition.org includes the Wall, showcasing touchscreen news and publications, the Forum, for community discussion, and Training, which includes courses, videos, SOPs, and symposia. To get started, interested researchers simply create user accounts. We describe the origins of the touchscreen testing system, the novel lines of research it has facilitated, and its increasingly widespread use in translational research, which is attributable in part to knowledge-sharing efforts over the past decade. We then identify the unique features of MouseTRAP that stand to potentially revolutionize translational research, and describe new initiatives to partner with similar platforms such as McGill's M3 platform (m3platform.org).     

Identifying and hurdling obstacles to translational research

Although there is overwhelming pressure from funding agencies and the general public for scientists to bridge basic and translational studies, the fact remains that there are significant hurdles to overcome in order to achieve this goal. The purpose of this Opinion article is to examine the nature of these hurdles and to provide food for thought on the main obstacles that impede this process.