内蒙古砧子山墓地古人的线粒体DNA多态性分析

为了研究内蒙古元上都遗址砧子山墓地古代人群的遗传结构及其可能来源,对该墓地古人的DNA进行了抽提、扩增和测序,获得了10个个体的线粒体DNA高可变一区序列.结合现代东亚、北亚、中亚和欧洲人的线粒体DNA数据进行了系统发育分析和多维尺度分析.研究结果表明:埋藏在砧子山墓地的元代居民为汉族人,主要是来自中国北方地区的汉族.本研究为揭示元代的复杂社会结构和人群历史动态提供了新的方法.     

Nuclear DNA sequences detect species limits in ancient moa

Ancient DNA studies have typically used multi-copy mitochondrial DNA sequences. This is largely because single-locus nuclear genes have been difficult to recover from sub-fossil material, restricting the scope of ancient DNA research. Here, we have isolated single-locus nuclear DNA markers to assign the sex of 115 extinct moa and, in combination with a mitochondrial DNA phylogeny, tested competing hypotheses about the specific status of moa taxa. Moa were large ratite birds that showed extreme size variation both within and among species. For some taxa, this large variation was hypothesized to represent sexual dimorphism, while for others it was argued to reflect the existence of different species. Our results show that moa were characterized by extreme reverse sexual dimorphism and as a result we have been able to clarify the number of moa species. For example, we show that the three recognized 'species' of Dinornis comprised only two monophyletic groups and that two of these 'species' comprised individuals of one sex only. This study also illustrates that single-locus nuclear DNA sequences can be consistently recovered from ancient material.     

Identification of the skeletal remains of a murder victim by DNA analysis

There is considerable anthropological and forensic interest in the possibility of DNA typing skeletal remains. Trace amounts of DNA can be recovered even from 5,500-year-old bones and multicopy human mitochondrial DNA sequences can frequently be amplified from such DNA using the polymerase chain reaction (PCR). But given the sensitivity of PCR, it is very difficult to exclude contaminating material. We now report the successful identification of the 8-year-old skeletal remains of a murder victim, by comparative typing of nuclear microsatellite markers in the remains and in the presumptive parents of the victim. This analysis establishes the authenticity of the bone DNA and the feasibility of bone DNA typing in forensic investigations.     

Pitfalls in the analysis of ancient human mtDNA

The retrieval of DNA from ancient human specimens is not always successful owing to DNA deterioration and contamination although it is vital to provide new insights into the genetic structure of ancient people and to reconstruct the past history. Normally, only short DNA fragments can be retrieved from the ancient specimens. How to identify the authenticity of DNA obtained and to uncover the information it contained are difficult. We employed the ancient mtDNAs reported from Central Asia (including Xinjiang, China) as an example to discern potentially extraneous DNA contamination based on the updated mtDNA phylogeny derived from mtDNA control region, coding region, as well as complete sequence information. Our results demonstrated that many mtDNAs reported are more or less problematic.Startim, from a reliable mtDNA phylogeney and combining the available modern data into analysis, one can ascertain the authenticity of the ancient DNA, distinguish the potential errors in a data set, and efficiently decipher the meager information it harbored. The reappraisal of the mtDNAs with the age of more than 2000 years from Central Asia gave support to the suggestion of extensively (pre)historical gene admixture in this region.     

New ancient DNA sequences suggest high genetic diversity for the woolly mammoth (Mammuthus primigenius)

Partial DNA sequences of cytochrome b gene (mtDNA) were successfully retrieved from Late Pleistocene fossil bone of Mammuthus primigenius collected from the Xiguitu County ( Yakeshi), Inner Mongolia Autonomous Region and from Zhaodong, Harbin of Heilongjiang Province in northern China. Two ancient DNA fragments (109 bp and 124 bp) were authenticated by reproducible experiments in two different laboratories and by phylogenetic analysis with other Elephantidae taxa. Phylogenetic analysis using these sequences and published data in either separate or combined datasets indicate unstable relationship among the woolly mammoth and the two living elephants, Elephas and Loxodonta . In addition to the short sequences used to attempt the long independent evolution of Elephantidae terminal taxa, we suggest that a high intra-specific diversity existed in Mammuthus primigenius crossing both spatial and temporal ranges, resulting in a complex and divergent genetic background for DNA sequences so far recovered. The high genetic diversity in the extinct woolly mammoth can explain the apparent instability of Elephantidae taxa on the molecular phylogenetic trees and can reconcile the apparent paradox regarding the unresolved Elephantidae trichotomy.     

New ancient DNA sequences suggest high genetic diversity for the woolly mammoth (Mammuthus primigenius)

Partial DNA sequences of cytochrome b gene (mtDNA) were successfully retrieved from Late Pleistocene fossil bone of Mammuthus primigenius collected from the Xiguitu County (Yakeshi), Inner Mongolia Autonomous Region and from Zhaodong, Harbin of Heilongjiang Province in northern China. Two ancient DNA fragments (109 bp and 124 bp) were authenticated by reproducible experiments in two different laboratories and by phylogenetic analysis with other Elephantidae taxa. Phylogenetic analysis using these sequences and published data in either separate or combined datasets indicate unstable relationship among the woolly mammoth and the two living elephants, Elephas and Loxodonta. In addition to the short sequences used to attempt the long independent evolution of Elephantidae terminal taxa, we suggest that a high intra-specific diversity existed in Mammuthus primigenius crossing both spatial and temporal ranges, resulting in a complex and divergent genetic background for DNA sequences so far recovered. The high genetic diversity in the extinct woolly mammoth can explain the apparent instability of Elephantidae taxa on the molecular phylogenetic trees and can reconcile the apparent paradox regarding the unresolved Elephantidae trichotomy.     

New ancient DNA sequences suggest high genetic diversity for the woolly mammoth (Mammuthus primigenius)

Partial DNA sequences of cytochrome b gene (mtDNA) were successfully retrieved from Late Pleistocene fossil bone of Mammuthus primigenius collected from the Xiguitu County (Yakeshi), Inner Mongolia Autonomous Region and from Zhaodong, Harbin of Heilongjiang Province in northern China. Two ancient DNA fragments (109 bp and 124 bp) were authenticated by reproducible experiments in two different laboratories and by phylogenetic analysis with other Elephantidae taxa. Phylogenetic analysis using these sequences and published data in either separate or combined datasets indicate unstable relationship among the woolly mammoth and the two living elephants, Elephas and Loxodonta. In addition to the short sequences used to attempt the long independent evolution of Elephantidae terminal taxa, we suggest that a high intra-specific diversity existed in Mammuthus primigenius crossing both spatial and temporal ranges, resulting in a complex and divergent genetic background for DNA sequences so far recovered. The high genetic diversity in the extinct woolly mammoth can explain the apparent instability of Elephantidae taxa on the molecular phylogenetic trees and can reconcile the apparent paradox regarding the unresolved Elephantidae trichotomy.     

Chloroplast DNA sequence from a miocene Magnolia species

DNA has been successfully extracted from several samples of preserved tissue, the oldest so far reported originating from a 13,000-year-old ground sloth. Both severe damage to the preserved DNA, primarily due to oxidation of the pyrimidines, has prevented the acquisition of sequence data from ancient samples except in a few cases. We report here the extraction of DNA from fossil leaf samples from the Miocene Clarkia deposit (17-20 Myr old), the amplification of an 820-base pair (bp) DNA fragment from the chloroplast gene rbcL from a fossil of the genus Magnolia, and its subsequent sequencing. The sequence was verified by comparison with published and unpublished rbcL sequences. These results extend our ability to analyse ancient DNA and may open new avenues into problems in palaeobotany, biogeography, and in the calibration of mutation rates.     

先秦儒家的财富动力思想及其现代意义

人类历史就是人类不断地创造财富用以满足人类需要的历史,不同的民族、不同的时代,人们在财富的创造过程中受不同的财富观念的支配,不同的财富观决定了不同的价值导向以及与此相联系的财富创造的动力和激情。先秦儒家的经济文化思想是中国经济文化思想的源头活水。儒家思想对人与人之间关系协调的重视超过对人与自然的关系,因而,更重视如何在社会各个阶级之间分配财富而不是如何增加社会物质财富的总量;在人与自然的关系上,儒家强调天人合一,不具有西方那种征服自然的强烈意识;对人们生财取利的经济行为的道德评价上,先秦儒家主张“以义制利”、“见利思义”、“富而好礼”,认为“义”是体现人的尊严和价值的终极价值;在对人们的求利欲望的分析上,把经济政治化、经济道德化,给本来作为手段、作为财富形式的金钱本身披上道德的外衣。受儒家传统财富观的熏陶,中华民族缺少了创造物质财富的冲动,但却营造了一个和谐的社会。在新的历史时期,我们要“致富思源”,这个“源”不仅是财富的源泉,而且包括那些对民族发展与富强产生积极作用和巨大推动力量的价值观、理念和思想。这就要求我们要以历史主义的态度和未来学的眼光去重新审视和重新认识先秦儒家的经济文化思想,并实现对传统的超越。     

具有生物降解功能的生物陶瓷材料研究

研究、制备了组元和结构类似于人体硬组织的多孔生物活性陶瓷材料HA-TCP[Ca_(10)(PO_4)_6(OH)_2-Ca_3(PO_4)_2]。在完成了生物实验和动物种植实验之后,该多孔生物活性材料在临床外科上得到了应用。X光显示表明,在短时间内植入的该材料能降解成硬组织、能在手术空洞中形成新骨小梁。文章较详细地介绍了HA-TCP粉末及材料的制备过程和适宜于软组织生长的孔隙结构和临床应用效果。     

Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, China

In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia. China to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modern horse clusters which were closely related to them representing a certain geographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified, which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in China.     

Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, China

In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia. China to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modern horse clusters which were closely related to them representing a certain geographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified, which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in China.     

多孔羟基磷灰石生物陶瓷的研究现状与进展

羟基磷灰石生物陶瓷与人体的无机组成和晶体结构相似 ,具有良好的生物活性和生物相容性 .多孔羟基磷灰石生物陶瓷 ,其相互连通的微孔有利于组织液的微循环并为羟基磷灰石深部的新生骨提供营养 ,促进纤维组织和新生骨的结合和生长 ,是一种性能优异的硬骨组织替代材料 .近年来 ,发明了一系列制备多孔羟基磷灰石陶瓷的方法 ,如有机泡沫浸渍法、添加造孔剂法、快速成型法等 .对于多孔羟基磷灰石生物陶瓷的研究 ,注重研究孔尺寸对多孔体与组织之间相互关系的影响 ,并逐步实现了对多孔体孔径的控制 .本文综述了多孔羟基磷灰石生物陶瓷的制备工艺、生物特性和发展趋势 .     

膝关节半月板疲劳状态下组织结构变化的初步研究

膝关节是人体承上启下的重要关节,位于该关节的股骨内外侧髁与胫骨内外侧髁之间的半月板尤其容易发生急性损伤或慢性劳损,此结构在承受与传导载荷、吸收振荡、稳定关节,协助关节润滑等方面有多种作用.故预防半月板的损伤以及损伤后的修复十分重要,否则会严重影响膝关节的功能.国内外对半月板研究比较重视,对此结构进行有组织学、生物力学、创伤学等多角度的研究.为了了解半月板在持续受力后的组织结构的变化,本研究进行了疲劳性损伤实验,观察其组织结构的变化.此研究有助于了解半月板损伤的机制,并为科学防治其损伤提供更多的理论依据.本研究采用INSTRON生物力学测试系统(Instron Co,USA)进行“压缩-扭转”实验,观察膝关节半月板各部位在受到一定外力持续性、旋转式挤压后,组织结构的变化,并与正常半月板各部位的组织结构进行比较,以了解其抗疲劳能力.从实验后组织切片的情况看,半月板经过“压缩-扭转”实验后,组织结构发生了明显的变化,主要表现有:1.软骨盘内细胞变形、软骨陷窝几乎消失,软骨细胞类似腱细胞.2.半月板内纤维排列发生严重紊乱,纤维间隙明显增大,并有纤维发生断裂的现象.3.半月板内未见血管,仅在软骨膜中可见少量血管分布,表明该结构在受到持续挤压以后,血供受到一定的破坏,半月板的营养供应受到影响,对该结构损伤后的修复会有明显影响.     

内蒙古和林格尔东周时期古代人群的分子遗传学分析

对10个古代个体的线粒体DNA高可变Ⅰ区进行了扩增和测序. 基于和林格尔古代人群与现今相关欧亚人群的mtDNA序列， 进行了系统发育分析和多维尺度分析. 研究结果表明, 和林格尔古代人群在母系遗传上与现在北亚人群的亲缘关系最近. 结合考古学、 人类学以及分子生物学的研究， 推断这个古代人群是从蒙古高原以及外贝加尔地区南下迁移至今天的内蒙古和林格尔地区的游牧人.     

用于DNA序列结构分析的特征抽取方法

人类基因组计划中的DNA序列图谱是生命科学和基因工程中的伟大成就,要解译隐藏在基因组中的生物信息还有一段很长的路要走,这是因为DNA序列的结构很难分析和识别．作者提出一种用于DNA序列结构分析的特征抽取方法．这种方法采用DNA序列码序的共生概率来抽取高维特征．然后采用相关法和／或贝叶斯分类器来分类结构模式．一些仿真试验的结果表明这种方法适合于DNA序列的结构分析。     

Molecular insights into human brain evolution

Rapidly advancing knowledge of genome structure and sequence enables new means for the analysis of specific DNA changes associated with the differences between the human brain and that of other mammals. Recent studies implicate evolutionary changes in messenger RNA and protein expression levels, as well as DNA changes that alter amino acid sequences. We can anticipate having a systematic catalogue of DNA changes in the lineage leading to humans, but an ongoing challenge will be relating these changes to the anatomical and functional differences between our brain and that of our ancient and more recent ancestors.     

生物压电陶瓷复合种植材料的微观结构表征

对生物压电陶瓷复合种植材料（ＨＡＢＴ）进行研究的结果表明，该材料不仅具有与人体组织的生物相容性和力学相容性，而且具有相似于人体自然骨所具有的压电性。采用Ｘ－射线衍射仪、激光拉曼光谱仪、热分析仪和扫描电镜等分析手段，对该材料进行了微观结构的表征。并对其结果进行了探讨。     

The genetic legacy of the Quaternary ice ages

Global climate has fluctuated greatly during the past three million years, leading to the recent major ice ages. An inescapable consequence for most living organisms is great changes in their distribution, which are expressed differently in boreal, temperate and tropical zones. Such range changes can be expected to have genetic consequences, and the advent of DNA technology provides most suitable markers to examine these. Several good data sets are now available, which provide tests of expectations, insights into species colonization and unexpected genetic subdivision and mixture of species. The genetic structure of human populations may be viewed in the same context. The present genetic structure of populations, species and communities has been mainly formed by Quaternary ice ages, and genetic, fossil and physical data combined can greatly help our understanding of how organisms were so affected.     

Genes mirror geography within Europe

Understanding the genetic structure of human populations is of fundamental interest to medical, forensic and anthropological sciences. Advances in high-throughput genotyping technology have markedly improved our understanding of global patterns of human genetic variation and suggest the potential to use large samples to uncover variation among closely spaced populations. Here we characterize genetic variation in a sample of 3,000 European individuals genotyped at over half a million variable DNA sites in the human genome. Despite low average levels of genetic differentiation among Europeans, we find a close correspondence between genetic and geographic distances; indeed, a geographical map of Europe arises naturally as an efficient two-dimensional summary of genetic variation in Europeans. The results emphasize that when mapping the genetic basis of a disease phenotype, spurious associations can arise if genetic structure is not properly accounted for. In addition, the results are relevant to the prospects of genetic ancestry testing; an individual's DNA can be used to infer their geographic origin with surprising accuracy-often to within a few hundred kilometres.