治疗性干细胞研究的伦理学方向

人类干细胞研究是一门新兴学科，一直处在伦理学的争论之中。本文为治疗性干细胞研究进行了伦理学辩护。指出正统思想的历史惯性作用、浪漫主义的非科学态度、“有利无伤”原则等存在的偏颇，探讨了宗教信仰等伦理学背后的更深层次的问题，论述了胚胎地位及体细胞克隆伦理学问题。提出了从事这项研究的科学家应有的态度。认为治疗性干细胞研究势在必行。     

应该重视生物医学期刊稿件中的医学伦理学问题

讨论了目前我国生物医学期刊涉及最多的生物医学研究中的受试者“知情同意”问题、干细胞研究中的伦理学问题和保护患者(或受试者)隐私权的问题。指出生物医学期刊工作者应该重视来稿中所涉及的医学伦理学问题。提出生物医学期刊在或受试者“知情同意”问题上应注意的几个问题,对干细胞研究中一些伦理学问题的观点,及保护患者(或受试者)隐私权的具体做法。     

干细胞研究

干细胞是一类具有自我更新和分化潜能的细胞。它具有自我更新能力(Self-renewing),能够产生高度分化的功能细胞。干细胞按照生存阶段分为胚胎干细胞和成体干细胞。在胚胎的发生发育中,单个受精卵可以分裂发育为多细胞的组织或器官。在成年动物中,正常的生理代谢或病理损伤也会引起组织或器官的修复再生。胚胎的分化形成和成年组织的再生是干细胞进一步分化的结果。胚胎干细胞是全能的,具有分化为几乎全部组织和器官的能力。而成年组织或器官内的干细胞一般认为具有组织特异性,只能分化成特定的细胞或组织。     

21世纪医学新景观——用干细胞治愈各种顽疾(二)

干细胞技术进展加剧了 胚胎竞争 通常认为,干细胞对未来治疗一些疑难病,如中风、老年痴呆症等多种疾病起着重要作用。从理论上讲,末发育的干细胞可用以形成人体的各种组织器官。例如,将实验室培养的神经细胞移植到中风病人的大脑中,便可改善其大脑受损部位的功能。目前争论的焦虑在于用病人自身细胞来克隆胚胎。最近,一份颇有影响的英国政府报告,呼吁人们允许科学家使用干细胞来培育胚胎。 意大利研究人员将少量未经发育的大脑干细胞放在成年实验鼠体     

人类胚胎干细胞研究中伦理学问题

人类胚胎干细胞研究对人类多种疾病的治疗有着广泛的应用前景，已成为21世纪生物医学研究热点。同样重要的是，人们还必须面对有关人类胚胎干细胞研究中的伦理学问题：人类胚胎的利益与成人(病人)利益之间的冲突问题。     

羊水多潜能干细胞的研究现状及前景展望

由于强大的自我更新能力和多向分化的潜能,多潜能干细胞被广泛应用于再生医学的研究.胚胎干细胞的研究因伦理道德问题而受到限制.羊水多潜能干细胞的发现为多潜能干细胞的研究开辟了新的领域,引起了广大学者的关注.该文就羊水多潜能干细胞的生物学性状、分化潜能、临床应用前景等予以综述.     

042 小鼠胚胎干细胞在遗传和发育毒理学中的应用

小鼠胚胎干细胞包括胚胎干细胞、胚胎生殖细胞和胚胎癌细胞3种类型,是唯一可以同时研究致突变物对未分化胚胎细胞和分化体细胞致突变性的细胞株,其对致突变物的敏感性因检测终点的不同而有所不同.在胚胎毒性检测方面,由于胚胎干细胞可以同时检测化学物对细胞增殖和分化的影响,从而大大提高了体外替代实验的预测符合率,有望成为化学物致畸试验的体外替代实验模型.同时,转基因技术的广泛应用和人源胚胎干细胞的建系将更有助于提高化学物胚胎毒性和致畸性体外预测符合率,但同时也存在较大的伦理学争议.     

诱导多潜能性干细胞的研究现状与临床应用前景

胚胎干细胞可作为细胞替代治疗中很好的供体细胞来源。但由于伦理学的原因,限制了胚胎干细胞在细胞替代治疗中的应用前景,而诱导多潜能性干细胞(induced pluripotent stem cell,iPS细胞)的出现则提供了一种替代胚胎干细胞的多潜能性细胞。因为iPS细胞的建立不需要卵细胞,也不破坏发育中的胚胎,所以iPS细胞不涉及伦理学问题。而且iPS细胞的建立相对简单,重复性好。因此,iPS细胞在细胞替代治疗和再生医学中有着广泛的应用前景。本文将回顾iPS细胞技术发展的历史,介绍现有的建立iPS细胞的不同方法和评估iPS细胞质量的手段,展望iPS细胞在细胞替代治疗上有待解决的问题和应用前景。     

小鼠胚胎干细胞在遗传和发育毒理学中的应用

小鼠胚胎干细胞包括胚胎干细胞、胚胎生殖细胞和胚胎癌细胞3种类型，是唯一可以同时研究致突变物对未分化胚胎细胞和分化体细胞致突变性的细胞株，其对致突变物的敏感性因检测终点的不同而有所不同。在胚胎毒性检测方面，由于胚胎干细胞可以同时检测化学物对细胞增殖和分化的影响，从而大大提高了体外替代实验的预测符合率，有望成为化学物致畸试验的体外替代实验模型。同时，转基因技术的广泛应用和人源胚胎干细胞的建系将更有助于提高化学物胚胎毒性和致畸性体外预测符合率，但同时也存在较大的伦理学争议。     

干细胞诱导分化生殖细胞的研究进展

干细胞是一类具有自我更新和分化潜能的细胞,包括胚胎干细胞和成体干细胞。胚胎干细胞是从囊胚内细胞团中获得的具有全能性的细胞,具备了分化成机体所有细胞类型的潜能,包括生殖细胞。近年来人类胚胎干细胞的研究取得了突破性进展,能在体外培养成精子细胞及成熟的卵母细胞,但存在免疫排斥、致瘤性和伦理学等问题,使其应用在临床治疗方面受限。成体干细胞是一种多能干细胞,理论上成体干细胞在一定条件下也可分化为生殖细胞。成体干细胞则可克服这些缺点,应用前景日益被看好。若将成体干细胞向生殖细胞的分化应用于临床,使分化成的生殖细胞能发育成具有生命的子代,那将为不育提供一条新的治疗途径。综述了胚胎干细胞及成体干细胞向生殖细胞分化方面的研究进展。     

Ethical boundary-work in the embryonic stem cell laboratory

Most accounts of the ethics of stem cell research are de- contextualised reviews of the ethical and legal literature. In this chapter we present a socially embedded account of some of the ethical implications of stem cell research, from the perspectives of scientists directly involved in this area. Based on an ethnography of two leading embryonic stem cell laboratories in the UK, our data form part of the findings from a larger project mapping the scientific, medical, social and ethical dimensions of innovative stem cell treatment, focusing on the areas of liver cell and pancreatic islet cell transplantation. We explore three key issues: what individual scientists themselves view as ethical sources of human embryos and stem cells; their perceptions of human embryos and stem cells; and how scientists perceive regulatory frameworks in stem cell research. We argue that these dimensions of laboratory practice are all examples of 'ethical boundary-work', which is becoming an integral part of the routine practice and performance of biomedical science. Our work adds to the relatively few sociological studies that explore ethics in clinical settings and to an even smaller body of work that explores scientists' views on the ethical issues relating to their research.     

人胚胎干细胞建系研究中的伦理管理

目的：建立国人胚胎干细胞系递交国际干细胞库,并在此基础上建立既符合中国国情又得到国际认可的相关伦理管理体系。方法：在比尔盖茨基金会的资助下,与北京大学生命科学院再生生物学实验室合作,募集胚胎建立人胚胎干细胞系,在此过程中探讨可行的符合国际伦理原则的相关伦理管理机制。结果：成功建立了国人胚胎干细胞系及相关伦理管理体系。结论：进行干细胞研究时应充分重视伦理问题,国际干细胞伦理管理与中国相关伦理原则是可以有机结合的。     

人胚胎干细胞建系研究中的伦理管理

目的：建立国人胚胎干细胞系递交国际干细胞库,并在此基础上建立既符合中国国情又得到国际认可的相关伦理管理体系。方法：在比尔盖茨基金会的资助下,与北京大学生命科学院再生生物学实验室合作,募集胚胎建立人胚胎干细胞系,在此过程中探讨可行的符合国际伦理原则的相关伦理管理机制。结果：成功建立了国人胚胎干细胞系及相关伦理管理体系。结论：进行干细胞研究时应充分重视伦理问题,国际干细胞伦理管理与中国相关伦理原则是可以有机结合的。     

Our cells/ourselves: creating human embryos for stem cell research.

In September 1999, the National Bioethics Advisory Commission (NBAC) submitted its report, "Ethical issues in human stem cell research." The report recommends federal funding for stem cell research involving human embryos remaining after infertility treatment. It also suggests that at some later time, it may be appropriate for there to be federal funding for this same research using embryos expressly created for research purposes. This essay compares this recommendation to a similar recommendation reached 5 years earlier by the Human Embryo Research Panel of the National Institutes of Health. The NBAC recommendation is found to be much better packaged relative to the (contentious) goal of securing federal funding for this type of research. The merits of this goal are not discussed here. Instead, disappointment is expressed with the absence of any serious discussion of the ethical issues raised by the future possibility of stem cell research using research embryos. The report's silence on this question is significant given its promise to promote public debate on the profound ethical issues regarding human stem cell research.     

Bioethics: problems and prospects within a research institute

Bioethics aims to identify an ethical framework by means of a multidisciplinary debate open to the scientific community, in order to allow support to scientists involved in biomedical research. The Istituto Superiore di Sanità (Italian National Institute of Health) has recognized the need for an ethical review board to cope with the problems of different researches carried on within the Institute. An Ethics Committee, better defined as an Independent Review Board, has therefore been appointed by the Minister of Health in order to evaluate different research proposals ranging from clinical trials to non clinical biomedical research. The experience of the first Committee is described.     

Envisaging the embryo in stem cell research: rhetorical strategies and media reporting of the ethical debates

Abstract How is the embryo defined, envisaged, imagined? Who speaks on its behalf, and how? Based on a study of UK press and TV news reporting, this paper identifies the rhetorical strategies used to assert competing ethical positions around embryonic stem cell research. We show how both sides in the dispute mobilise metaphors and use personification to recruit support; and how they promote different ideas about the embryo's significance, size, and social embeddedness and present competing narratives about its origins, destiny and ‘death’. The role of visual representation is key here. It does not follow the usual pattern whereby, in the abortion debate, those ‘on the side’ of the fetus display its image while those who are ‘pro‐choice’ shy away from this. In the stem cell debate the pattern is inverted, highlighting the role of technologies of visualisation in defining what counts as human. Our analysis also shows how the media coverage marginalises women's perspectives, disregards more fundamental challenges to science, side‐lines concerns about effectiveness or safety and curtails discussion of broader issues. We reflect on the media processes restricting debate in this way and conclude by identifying opportunities for a more inclusive discussion of science ethics.     

The ethical challenge of stem cell research.

This article analyzes the ethical issues raised by embryonic stem cell research and recent recommendations by the National Bioethics Advisory Commission (NBAC) regarding federal support for this research. The authors identify the key ethical issue as the moral significance that should be granted to early embryos and discuss arguments supporting the diverse answers to that question and the implications each view has on the formulation of rules and policies for stem cell research. The authors conclude that several of NBAC's recommendations regarding the derivation of stem cells from embryos for research are ethically justifiable and sound public policy.     

Ethical Aspects of the Use of Stem Cell Derived Gametes for Reproduction

A lot of interest has been generated by the possibility of deriving gametes from embryonic stem cells and bone marrow stem cells. These stem cell derived gametes may become useful for research and for the treatment of infertility. In this article we consider prospectively the ethical issues that will arise if stem cell derived gametes are used in the clinic, making a distinction between concerns that only apply to embryonic stem cell derived gametes and concerns that are also relevant for gametes derived from adult stem cells. At present, it appears preferable to use non-embryonic stem cells for the derivation of gametes. Adult stem cell derived gametes do not present any problems with regard to the moral status of the human embryo, bypass the safety risks linked to SCNT and do not present any ambiguity or novel problems with regard to informed consent, psychological consequences for the child or genetic parenthood. A remaining ethical concern, however, regards the safety of the procedure in terms of the welfare of the resulting children. This should spark a thorough reflection on how far one must go to accommodate a person’s wish to have a genetically related child.     

National risk signatures and human embryonic stem cell research in mainland China

The international development of human embryonic stem cell research has become closely tied to global bioethics, which places moral responsibility on stem cell researchers. This article argues that the development of bioethical regulation of human embryonic stem cell research is better understood by approaching the institutionalisation of bioethics in terms of risk perceptions of stem cell scientists. Eschewing approaches that understand bioethical risk as a mere matter of morality or as a social construct, this article emphasises the materiality and strategic reasoning of bioethical views on risks associated with human embryonic stem cell research. Such an approach allows the identification of forms of risk rooted in the everyday practice of Chinese human embryonic stem cell research, including moral risk (as a violation of cultural values), material risk (in relation to the distribution of material resources and wealth), political risk (in terms of the political economy of bioethics and public debate) and reputational risk (in terms of personal and national honour). Although this analysis builds on Tom Horlick-Jones's concept of risk signatures of new technologies, which emphasise the capacities of different technologies to engender and delimit the particular social and cultural interpretations of the risks they generate, the article reveals the existence of a certain global awareness among stem cell scientists of risk signatures. They display a creative and strategic awareness regarding the possible opportunities and constraints the risk signature of human embryonic stem cell research affords in their particular institutional context compared to those of others abroad and at home in different environments. The existence of this form of reflexivity requires recognition and methodological accommodation.     

From fibroblasts and stem cells: implications for cell therapies and somatic cloning

Pluripotent embryonic stem cells (ESCs) from the inner cell mass of early murine and human embryos exhibit extensive self-renewal in culture and maintain their ability to differentiate into all cell lineages. These features make ESCs a suitable candidate for cell-replacement therapy. However, the use of early embryos has provoked considerable public debate based on ethical considerations. From this standpoint, stem cells derived from adult tissues are a more easily accepted alternative. Recent results suggest that adult stem cells have a broader range of potency than imagined initially. Although some claims have been called into question by the discovery that fusion between the stem cells and differentiated cells can occur spontaneously, in other cases somatic stem cells have been induced to commit to various lineages by the extra- or intracellular environment. Recent data from our laboratory suggest that changes in culture conditions can expand a subpopulation of cells with a pluripotent phenotype from primary fibroblast cultures. The present paper critically reviews recent data on the potency of somatic stem cells, methods to modify the potency of somatic cells and implications for cell-based therapies.