高原鼠兔个性特征的地理变异及其对环境的适应

个性特征是指动物稳定且可遗传的综合行为特征,反映出其对特定环境的适应。限制性假说认为个性特征主要受遗传因素制约,个体间行为的表达差异不以环境条件而发生随意性改变;然而,适应性假说则认为个性特征主要由环境因素决定,生活于相同环境中的物种,其个性特征将产生趋同现象。本研究通过比较2个高原鼠兔地理种群的个性特征,检验适应性假说和限制性假说的相关预测。结果表明,刚察县高原鼠兔野外种群个体的行为特征聚为3类,玛沁县则为2类。实验室内驯化2-3个月后,两个地理种群个体行为特征聚为1类。两地理种群个体的观察、攀爬行为及边缘区域活动、移动累计时间均无显著差异,但静止累计时间存在明显地理差异。个体的中心区域活动累计时间在野外和驯化后均存在明显差异,且与地理空间的交互作用不显著。两地理种群之间个体的温顺性无明显差异;心率亦无显著差异。高原鼠兔个性特征中主要行为参数无显著的地理差异,主要由遗传因素决定,验证了限制性假说的相关预测。     

Construction of the first shuttle vectors for gene cloning and homologous recombination in Mycoplasma agalactiae

Mycoplasma agalactiae is a worldwide ruminant pathogen that causes significant economic losses by inflicting contagious agalactia in sheep and goats. The development of efficient control strategies requires a better understanding of the mycoplasma factors that promote successful infection. However, lack of genetic tools has been a major impediment in studying the pathogenic mechanisms of M. agalactiae. This study describes the identification and cloning of the M. agalactiae origin of replication (oriC) in order to construct the first shuttle vectors for targeted gene disruption, gene complementation and expression studies. Additionally, this report provides the first evidence of the occurrence of homologous recombination and the functionality of heterologous tetM determinant in this pathogen.     

Genetics and molecular biology of methanotrophs

Abstract Over the last 20 years or so, the obligate methane-oxidizing bacteria (methanotrophs) have attracted considerable interest. As they grow on a relatively cheap and abundant carbon source, they appeared ideal organisms for the production of bulk chemicals, single-cell protein and for use in biotransformations. More recently their cooxidation properties have been investigated for bioremediation, including the removal of chlorinated compounds such as trichloroethylene from polluted groundwaters. These studies have resulted in a great deal of information on the physiology and biochemistry of methanotrophs but sadly the molecular biology and genetic studies of these organisms have lagged behind. This has been in part due to the obligate nature of the methanotrophs and the refractory nature of such organisms to conventional genetic analysis. However, the more recent availability of broad-host range plasmids coupled with improvements in molecular biology methods have allowed the development of molecular genetic techniques for methanotrophs. The purpose of this review is to summarize what is known about the genetics and molecular biology of methanotrophs and how this information can be used to complement previous and current biochemical studies on the unique property of these bacteria, i.e. the ability to oxidize methane to methanol. Recent developments in molecular ecology techniques that may be applied to these apparently ubiquitous organism are also considered.     

Ancient DNA studies and new bioethic problems

The development of the ancient DNA technique allows the genetic study of vanished human populations, some of them, as Fueguians and Tasmanians, of great anthropological interest. This possibility, however, involves some new bioethic problems, concerning the origin of the skeletal samples that can be analyzed and the moral authority of living aboriginals with respect to human remains of perhaps several thousand years of antiquity. It is my opinion that, despite some skeletal collections might be unethically gathered by the 19th century anthropologists, the vanished human populations must be genetically studied. If not, after contribute to their disappearance, we will be now ignoring their contribution to the humankind diversity.     

Cryptorchidism: an indicator of testicular dysgenesis?

Cryptorchidism is a common ailment of new-born boys, affecting 1–9% of full term boys at birth. Cryptorchidism has been associated with an increased risk of testicular cancer and reduced fertility. Aetiology of cryptorchidism remains obscure in most cases. Familial occurrence suggests a heritable susceptibility to cryptorchidism; however, seasonal variation in the incidence of cryptorchidism suggests that environmental factors also contribute. Testicular descent is characterised by androgen-dependent regression of cranial suspensory ligament and androgen + insulin-like hormone 3 (Insl3)-dependent gubernacular outgrowth. Even though hormonal defects are rarely detected in patients, both hypo-and hypergonadotropic hormonal patterns have been associated with cryptorchidism. Moreover, cryptorchid boys have significantly reduced serum androgen bioactivity at 3 months of age when normal boys have a strong surge of reproductive hormones. Defects in Insl3 action cause cryptorchidism in male mice, and over-expression in female mice causes ovarian descent. Defects in leucine-rich repeat-containing G-protein-coupled receptor 8/G-protein-coupled receptor affecting testis descent (LGR8/GREAT), the receptor for Insl3, manifest the same phenotype as Insl3 knockout mutants. Even though mutations found in Insl3 and LGR8/GREAT genes are not a common cause of cryptorchidism in patients, it remains to be resolved whether low Insl3 levels during development are associated with cryptorchidism. Cryptorchidism may reflect foetal testicular dysgenesis that may later manifest as subfertility or testicular cancer.This work was supported by the Turku University Central Hospital, the Academy of Finland and the European Commission (contracts BMH4-CT96-0314, QLK4-CT1999-01422, QLK4-CT2001-00269 and QLK4-CT2002-00603).     

Do American born Japanese children still grow faster than native Japanese?

Growth patterns of Japanese schoolchildren in Hawaii, composed of 2,954 boys and 3,213 girls aged between 11 and 17, were compared with those comparable groups of Japanese schoolchildren in Japan based on the data published by the Japanese Ministry of Education. Growth characteristics studied were height, weight, and relative weight index, weight/(height). The Hawaii-Japanese boys were taller at early ages but the difference disappeared by age 16. Native Japanese girls were shorter than Hawaii-Japanese until age 13, but they overtook the latter by age 14, exceeding them in height after age 15. A similar pattern was found in weights of girls but the Hawaii-Japanese boys remained consistently heavier by 5.0 to 9.0 kg than native Japanese. The relative weight measure indicated that the Hawaii boys were more "obese" than native Japanese boys for the growth period studied; whereas the same tendency was maintained until age 15 in girls. These observations indicate a marked degree of convergence of the patterns of physical growth of the two populations, whose differences were unmistakably in favor of American born children in earlier studies. It is concluded that the convergence is due largely to the improved environmental conditions in Japan in recent years.     

Expanding the modern synthesis

The Modern Evolutionary Synthesis formalizes the role of variation, heredity, differential reproduction and mutation in population genetics. Here we explore a mathematical structure, based on the asymptotic limit theorems of communication theory, that instantiates the punctuated dynamic relations of organisms with their embedding environments, including the possibility of the transfer of heritage information between different classes of organism. The approach applies a standard coevolutionary argument to genes, environment, and gene expression reconfigured as interacting information sources. In essence, we provide something of a formal roadmap for the modernization of the Modern Synthesis, making applications to both relatively rapid evolutionary punctuated equilibrium and to the conservation of ecological interactions across deep evolutionary time.     

Closing remarks

Closing remarks to Human genetics - uncertainties and the financial implications ahead. A Discussion held at the Royal Society on 25 and 26 September 1996, and organized and edited by R. M. Anderson. <br>     

我国生物医药园区发展特点及未来发展建议

对我国生物医药园区中的108个园区进行了调研,对我国生物医药园区的发展现状有了初步的认识。经过调研发现,部分地区生物医药园区布局合理,带动区域经济健康发展。全国初步形成三大生物医药产业集群。园区成为生物医药产业发展的重要依托。最后,对我国生物医药园区发展的提出了五条建议。     

CONSTRUCTION AND PRACTICE OF MEDICAL RESPONSIBILITY: DILEMMAS AND NARRATIVES FROM GERIATRICS

A narrative approach is employed in this article about dilemmasand physician reasoning in geriatric medicine in order toexplore the moral-medical worlds of urban American physicians.Reconstructed dilemmas, in the form of stories told by 51doctors, are analyzed as cultural documents of both clinical-moralknowledge and practice and the physician as moral actor. Discussionfocuses on ways in which responsibility is constituted and enactedthrough a particular language of clinical action. This analysisopens the subject of bioethics to a range of infrequently discussedissues that physicians cite as deeply troubling and contributesto a broadening of anthropological approaches useful in the studyof bioethics.     

High efficiency,Site-specific Transfection of Adherent Cells with siRNA Using Microelectrode Arrays (MEA)

The discovery of RNAi pathway in eukaryotes and the subsequent development of RNAi agents, such as siRNA and shRNA, have achieved a potent method for silencing specific genes^1-8 for functional genomics and therapeutics. A major challenge involved in RNAi based studies is the delivery of RNAi agents to targeted cells. Traditional non-viral delivery techniques, such as bulk electroporation and chemical transfection methods often lack the necessary spatial control over delivery and afford poor transfection efficiencies^9-12. Recent advances in chemical transfection methods such as cationic lipids, cationic polymers and nanoparticles have resulted in highly enhanced transfection efficiencies¹³. However, these techniques still fail to offer precise spatial control over delivery that can immensely benefit miniaturized high-throughput technologies, single cell studies and investigation of cell-cell interactions. Recent technological advances in gene delivery have enabled high-throughput transfection of adherent cells^14-23, a majority of which use microscale electroporation. Microscale electroporation offers precise spatio-temporal control over delivery (up to single cells) and has been shown to achieve high efficiencies^{19, 24-26}. Additionally, electroporation based approaches do not require a prolonged period of incubation (typically 4 hours) with siRNA and DNA complexes as necessary in chemical based transfection methods and lead to direct entry of naked siRNA and DNA molecules into the cell cytoplasm. As a consequence gene expression can be achieved as early as six hours after transfection²⁷. Our lab has previously demonstrated the use of microelectrode arrays (MEA) for site-specific transfection in adherent mammalian cell cultures^17-19. In the MEA based approach, delivery of genetic payload is achieved via localized micro-scale electroporation of cells. An application of electric pulse to selected electrodes generates local electric field that leads to electroporation of cells present in the region of the stimulated electrodes. The independent control of the micro-electrodes provides spatial and temporal control over transfection and also enables multiple transfection based experiments to be performed on the same culture increasing the experimental throughput and reducing culture-to-culture variability. Here we describe the experimental setup and the protocol for targeted transfection of adherent HeLa cells with a fluorescently tagged scrambled sequence siRNA using electroporation. The same protocol can also be used for transfection of plasmid vectors. Additionally, the protocol described here can be easily extended to a variety of mammalian cell lines with minor modifications. Commercial availability of MEAs with both pre-defined and custom electrode patterns make this technique accessible to most research labs with basic cell culture equipment.     

普鲁士蓝纳米粒子在生物医学诊断和治疗中的应用及进展

随着生物医学诊断和治疗的持续深入研究,出现了多种医学诊断和治疗新方法,为人类的健康提供了更大的保证,其中纳米生物技术在生物医学诊断和治疗中的应用日益增多,基于纳米技术,开发传统材料的生物医学新应用成为了人们的研究热点。普鲁士蓝是一种历史悠久的蓝色染料,其制备过程简单、绿色、成本低,化学结构稳定,具有优良的物理、化学、光学以及磁性等性能,已经在许多领域得到了广泛的应用。近年来,普鲁士蓝开始在生物医学诊断和治疗领域中崭露头角,它已经成功的被开发为新型的核磁共振造影剂和光声成像造影剂,并且在药物输送系统和光热治疗等领域也开始占有一席之地,开发基于纳米技术的普鲁士蓝的生物医学应用已经成为极具吸引力的研究方向。本文对普鲁士蓝在生物医学诊断和治疗中的应用及进展进行综述。     

Anthropological and Sociological Critiques of Bioethics

Anthropologists and sociologists offer numerous critiques of bioethics. Social scientists criticize bioethicists for their arm-chair philosophizing and socially ungrounded pontificating, offering philosophical abstractions in response to particular instances of suffering, making all-encompassing universalistic claims that fail to acknowledge cultural differences, fostering individualism and neglecting the importance of families and communities, and insinuating themselves within the “belly” of biomedicine. Although numerous aspects of bioethics warrant critique and reform, all too frequently social scientists offer ungrounded, exaggerated criticisms of bioethics. Anthropological and sociological critiques of bioethics are hampered by the tendency to equate bioethics with clinical ethics and moral theory in bioethics with principlist bioethics. Also, social scientists neglect the role of bioethicists in addressing organizational ethics and other “macro-social” concerns. If anthropologists and sociologists want to provide informed critiques of bioethics they need to draw upon research methods from their own fields and develop richer, more informed analyses of what bioethicists say and do in particular social settings.     

Republication: In That Case

The case study examines an issue of public health ethics and obesity. How should healthy diets be developed? Can schools associate themselves with commercial fastfood companies? What are the ethical issues related to diet campaigns in an Asia context. The case study elicits several responses from different perspectives. The case study invites readers to think of different cultural contexts and broad issues.     

Do adolescents' bioethical decisions differ from those of experts?

If our students are to become well-informed decision makers then they need to be aware of the practical applications of current developments in biotechnology, and appreciate the social and bioethical implications of this relatively new and controversial science. In this study, Year 10 (14 – 15 year old) science students in two schools were taught biotechnology courses that introduced them to bioethics. At the conclusion of the course, students completed a survey in which they made a decision about three bioethical dilemmas, and gave reasons to support their decision. The students' responses and reasons were compared with those of three experts. Although there was variation amongst students, the results of the survey suggested that the majority of students tended to resolve and justify their decisions in a way that was naive, idealistic, and rights based. Compared to the experts, the students seemed to give undue emphasis to the bioethical principle of autonomy. In addition, the reasons supplied by many of the students to support their decisions suggested that they did not consider long term consequences. These findings have ramifications for teachers who wish to include bioethical dilemmas in their teaching.     

Environmental Change, Injustice and Sustainability

This paper argues that a combination of increasing inequality, hypocrisy, population growth and adverse global environmental change imperils our civilisation. Selected examples of existing inequality and the immoral treatment of human beings are provided from countries of the Asia Pacific. There is also limited discussion of the global eco-social crisis, stressing the links between environmental scarcity and the human responses of resentment, conflict, terrorism and ill-governance. The essay contends that just as the lives of unborn humans similar to us are of interest and value to bio-ethicists, so too should be the lives and descendants of people who are unlike us, even if such people are perceived to be substantially different to ourselves in terms of status, culture and spending power. It is argued that it is in the interests of ourselves, society, and global civilisation that the lives of such people are considered and where possible improved in order to foster the “sustainability transition” needed to secure our collective future. The essay concludes with a discussion of an important element for securing our future: the development and implementation of alternative economic systems which will provide more accurate indicators of global progress.