三种华枝断肢再生的研究

目（竹节虫目）的昆虫具有很强的断肢再生能力。该文通过对华枝属（Ｓｉｎｏｐｈａｓｍａｓｐｐ）三种昆虫的实验,表明其再生能力与断肢发生的时间及数量有关。断肢１只或２只的１～４龄虫体发育至成虫期或至若虫末龄时,其再生足的长度与相应的正常足长度相近。若在５龄初时断肢１～２只,也具有再生能力,但至成虫期其再生足的长度则短于相对应的正常足。若在６龄及成虫时断肢,则无再生能力（若６龄时出现断肢再生,则若虫期多为７龄）。实验结果还表明,若断肢为３只或３只以上,则虫体不能存活,且多在断肢后２～３ｄ内死亡。观察中尚发现,再生足生长速度明显高于正常足。而且,断肢的龄期越高,再生足生长速度越快。再生足的伸长生长与正常足一样,均出现于虫体蜕皮时。     

三种华枝断肢再生的研究

目(竹节虫目)的昆虫具有很强的断肢再生能力。该文通过对华枝属(Sinophasma spp)三种昆虫的实验,表明其再生能力与断肢发生的时间及数量有关。断肢1只或2只的1～4龄虫体发育至成虫期或至若虫末龄时,其再生足的长度与相应的正常足长度相近。若在5龄初时断肢1～2只,也具有再生能力,但至成虫期其再生足的长度则短于相对应的正常足。若在6龄及成虫时断肢,则无再生能力（若6龄时出现断肢再生,则若虫期多为7龄）。实验结果还表明,若断肢为3只或3只以上,则虫体不能存活,且多在断肢后2～3 d内死亡。观察中尚发现,再生足生长速度明显高于正常足。而且,断肢的龄期越高,再生足生长速度越快。再生足的伸长生长与正常足一样,均出现于虫体蜕皮时。     

斑马鱼心脏再生的研究

人类心脏损伤后不可再生,使得心脏疾病成为威胁人类生命的主要疾病之一。斑马鱼等其他非哺乳动物类脊椎动物的心脏在受损伤后可以再生,再加上其遗传操作已十分成熟,使其成为研究脊椎动物心脏再生的一个极好模型。本文总结了国内外关于斑马鱼心脏再生的最新进展、并分析了心脏再生特异的分子机制以及涉及再生现象的保守机制,进一步提出了这些研究对于人类心脏疾病的治疗的可借鉴之处。     

常温常压下蚯蚓不同体段再生体节和再生质量研究

将蚯蚓从不同位置切断,得到有头无尾、无头有尾、无头无尾3组19种类型的体段,在常温(15～18℃)常压下培养,观察和记录其再生体节数和再生质量.结果表明,切断位置不同,其再生体节和再生质量有明显的差异.切后都保留了心脏、生殖环、脑或只切除了脑,所剩体节数均在实验所用蚯蚓的体节数的1/2以上的蚯蚓体段,再生体节数明显,其它各体段组再生体节数不明显或无.在培养13～27 d内死亡的蚯蚓,其再生质量呈减小趋势;能存活到48 d之后的蚯蚓,在有头无尾、无头有尾体段组中,再生质量呈增加趋势,在无头无尾体段组中,再生质量呈下降趋势.     

再生研究与再生医学

再生是大自然的普遍现象。再生过程干细胞的激活与成熟细胞的去分化,再生与肿瘤的关系等都使得这一领域越来越成为各个国家研究与投资的热点。对自然再生过程的研究将有助于发展人类的细胞疗法。随着对再生研究的深入,将有可能揭示如何选择性的再次激活指导哺乳动物早期发育的基因和蛋白质,以此来诱导受伤或生病的人类组织的再生,再生医学方兴末艾。     

海鞘再生的细胞学过程及其调控机制研究进展与展望

再生现象在后生动物中普遍存在,但不同物种的再生能力存在显著差别。无脊椎动物如水螅和涡虫等再生能力较强,具有部分组织或细胞即可再生出一个完整个体的能力,被称为整体再生;而脊椎动物的再生能力相对较弱,局限在某些特定器官或身体结构,被称为部分再生,如蝾螈的附肢。海鞘作为进化上介于无脊椎动物与脊椎动物之间的尾索动物,既包括具备整体再生能力的群居类型,如拟菊海鞘(Botrylloides leachii),其可以利用部分血管残片即可再生出完整个体;也包括只具有部分再生能力的单体海鞘类型,如玻璃海鞘(Ciona robusta),其只有出入水管和神经复合体等器官才可再生。鉴于海鞘的进化地位及其具有的不同再生能力类群,近年来逐渐成为研究再生的理想模式动物。该文系统分析总结了海鞘不同类群所具备的整体再生和部分再生的各自细胞学过程及其调控机制,并比较归纳了导致海鞘不同群体具有不同再生能力差别的可能机制,展望了海鞘再生研究的未来方向,为理解后生动物再生能力的演化和调控机制提供参考。     

生物组织再生材料

日前,库克医疗在中国正式推出一款高端生物组织再生材料——百得塞。据印第安纳大学与普渡大学外科学教授威廉？乌登介绍,百得塞有四项优点：包括携带生物信号强化组织再生、强效抗感染、完全再生新组织及再生组织强韧持久。该再生材料已被证实可以应用于各种疝的治疗。     

葡萄再生系统研究进展

综述近年来葡萄再生系统的研究进展及存在问题。葡萄器官发生型再生途径易产生不定芽 ,但嵌合体的比例较高 ,胚状体再生途径诱导胚状体较困难 ,仅有少部分葡萄品种能成功。今后葡萄遗传转化的重点是高效再生途径的研究。     

BMP信号通路在再生中的作用研究进展

再生是指生物体可以重新生长出损伤的组织和器官的生物学过程。对再生的研究过去主要集中于形态学观察及描述等方面,随着现代生物学的快速发展,对再生的分子机制有了更多的研究,发现多种信号通路参与了再生过程,如FGF信号通路、BMP信号通路、HEDGEHOG信号通路等。研究发现,BMP为转化生长因子β(TGF-β)家族的重要成员,BMP信号通路可以调节细胞的增殖和分化,在胚胎发育过程中具有重要的调控作用。但是目前对于BMP在再生过程中的作用研究相对较少,本文对BMP信号通路在几种模式生物再生过程中的作用进行了综合分析,以期为进一步研究BMP信号通路在再生中的作用提供理论借鉴。     

生物再生及其相关的几个问题

人类对生物科学的研究,经历了一个从生物宏观现象描述到个体生物形态的解剖,从生物个体形态解剖到生物机能微观分析的发展过程。再生现象广泛存在于整个生物界,它与生物的发育、生长、繁殖等诸多方面息息相关。尤其是飞速发展的现代生物学及其相关学科的许多研究领域的问题,如农林学方面的科学育种、快速繁殖涉及的接合力和组织培养的关键性问题,医学手术中的伤口愈合等等,无不与生物的再生相联系。所以作者深信:对生物再生现象在生物界广泛性的重视;对生物再生现象意义和作用的     

Deer antler regeneration: cells, concepts, and controversies

The periodic replacement of antlers is an exceptional regenerative process in mammals, which in general are unable to regenerate complete body appendages. Antler regeneration has traditionally been viewed as an epimorphic process closely resembling limb regeneration in urodele amphibians, and the terminology of the latter process has also been applied to antler regeneration. More recent studies, however, showed that, unlike urodele limb regeneration, antler regeneration does not involve cell dedifferentiation and the formation of a blastema from these dedifferentiated cells. Rather, these studies suggest that antler regeneration is a stem-cell-based process that depends on the periodic activation of, presumably neural-crest-derived, periosteal stem cells of the distal pedicle. The evidence for this hypothesis is reviewed and as a result, a new concept of antler regeneration as a process of stem-cell-based epimorphic regeneration is proposed that does not involve cell dedifferentiation or transdifferentiation. Antler regeneration illustrates that extensive appendage regeneration in a postnatal mammal can be achieved by a developmental process that differs in several fundamental aspects from limb regeneration in urodeles.     

森林更新与空间异质性

森林更换是一个重要的生态学过程,一直是森林生态系统动态研究中的主要领域之一。森林更新受物理环境、自然干扰、人为干扰、更新树种特性、树种对干扰的反应等因素及其相互作用的影响。这些生物和非生物的因素随空间和时间而不断变化,构成了森林的空间异质性和时间异质性,使森林更新具有空间和时间上的变化特点,表现在异质性的格局和过程中。探索森林更新与空间异质性的内在规律,可揭示空间格局对更新的生态学过程的潜在作用机制。本文主要综述了近年来有关森林更新与空间异质性研究的主要内容和一些观点,分析了更新中空间异质性的来源,着重评述了空间异质性的生境及更新树种的反应、小尺度的空间异质性与更新动态、林分中光有效性的空间异质性与更新格局以及土壤和更新的空间异质性尺度的关联性等方面的研究。     

海南岛木麻黄海防林天然更新特征及更新树种筛选

天然更新是森林资源再生产的一个重要的生态学过程,良好的天然更新可促进人工林向近自然林的方向转变。为了解海南木麻黄海防林天然更新现状和特征,筛选出自然条件下天然更新良好的树种。该研究在海南岛木麻黄海防林内共计设立临时样地73块,样地总面积为2.51 hm~2,采用典型抽样的调查方法对海南全岛木麻黄海防林天然更新状况进行系统调查,应用天然更新密度及物种丰富度等指标对干、湿不同气候区木麻黄天然更新特征进行比较分析,并应用更新密度、更新指数等指标对天然更新质量较好的树种进行筛选。结果表明:(1)海南岛木麻黄海防林下天然更新质量整体不佳,木麻黄自身虽无法实现天然更新,但局部其他树种天然更新良好,更新良好的比例为15.1%。(2)湿润区天然更新丰富度及物种多样性远优于半干旱区,其中湿润区样地更新树种为28科、50属、59种,半干旱区样地更新的树种为6科、6属、6种。(3)乔木更新情况优于灌木。(4)潺槁木姜子、鸦胆子、台湾相思、榄仁树等具有较强的天然更新性能,适合与木麻黄混交,可以作为木麻黄海防林的混交树种或伴生树种。     

Regeneration inducers in limb regeneration

Limb regeneration ability, which can be observed in amphibians, has been investigated as a representative phenomenon of organ regeneration. Recently, an alternative experimental system called the accessory limb model was developed to investigate early regulation of amphibian limb regeneration. The accessory limb model contributed to identification of limb regeneration inducers in urodele amphibians. Furthermore, the accessory limb model may be applied to other species to explore universality of regeneration mechanisms. This review aims to connect the insights recently gained to emboss universality of regeneration mechanisms among species. The defined molecules (BMP7 (or2) + FGF2 + FGF8) can transform skin wound healing to organ (limb) regeneration responses. The same molecules can initiate regeneration responses in some species.     

Efficient regeneration of fertile barley plants from callus cultures of several Nordic cultivars

The regeneration potential of three major Estonian barley cultivars was tested and compared to that of the Finnish cultivar Kymppi. Two different regeneration systems were used. The first was characterized by the high maltose concentration (60 g l(-1)) and by the use of 2,4D together with two different combinations of amino acids in the callus induction medium followed by the regeneration medium containing BAP (2 mg l(-1)) and 2,4D (0.2 mg l(-1)). The second exploited callus induction medium that contained Dicamba, lower concentrations of maltose (30 g l(-1)) and higher concentrations of myo-inositol and thiamine and different set of amino acids and regeneration medium that contained higher concentrations of Cu2+ and inorganic nitrogen accompanied by lower concentrations of NH4+ and BAP, when compared to the first regeneration system. The second regeneration system used produced significantly higher rates of callus induction, callus growth and regeneration of plantlets. However, it yielded also many albino plants (up to 51%), whereas the first regeneration system used did not produce practically any albino plants. No major genotype-dependent differences were observed in comparison between two regeneration systems - in both systems higher regeneration potential of Anni, Elo and Kymppi contradicted to the low regeneration potential of Teele. It is concluded that the continuous somatic embryogenesis on the regeneration medium allows the regeneration of many plants from the same callus over long periods of time and makes available highly efficient regeneration protocols for Estonian and Finnish barley cultivars.     

Effect of culture methods on the regeneration of albino rice (Oryza sativa L.) plantlets

In our study, we investigated the effects of regeneration conditions on both green and albino rice plants (Oryza sativa L.). The regeneration frequency of an albino cell line was compared to a normal cell line obtained from mature seed under two kinds of culture conditions; namely, the static culture on semi-solid regeneration medium and the suspension culture in liquid regeneration medium. The albino cell line, from which only albino plantlets were regenerated, was induced from the albino leaf segments. There were no significant differences in the regeneration frequencies between normal and albino calli on the semisolid regeneration medium. On the other hand, the frequency of regeneration of albino calli was significantly lower than that of the control specifically in the liquid regeneration medium.     

生长素与乙烯在沙田柚上胚轴不定芽再生中的作用

结果表明,6 BA只能诱导较低频率的不定芽再生,IBA的加入可以促进不定芽的再生。从再生率与单位外植体再生芽数综合考虑,以高浓度IBA(1.5mg·L 1)与低浓度6 BA(0.5mg·L 1)配合的效果最佳,加入生长素极性运输的调节剂TIBA与Flavone可进一步提高不定芽的再生频率。乙烯抑制上胚轴不定芽的再生,而乙烯生理作用的拮抗剂Ag+与生物合成抑制剂AOA、Co+可以显著提高不定芽再生频率。水杨酸(SA)也抑制不定芽的再生。     

Effect of Combined Changes in Culture Medium and Incubation Conditions on the Regeneration from Immature Embryos of Elite Varieties of Winter Wheat

In this study, tissue culture method for plant regeneration from immature embryos of elite Hungarian winter wheat varieties was established. The influence of the growth regulators and the concentration of macroelements in the regeneration medium and of the incubation temperature and light intensity on regeneration frequency were investigated. The most noticeable effect on regeneration frequency was achieved by simultaneously reducing both the incubation temperature to 23 °C and the concentration of macroelements in the regeneration medium to half-strength. This modification increased the average regeneration frequency from about 10–78%. Changes in the light intensity and temperature gave an average plant regeneration frequency of 83%.     

Ethylene influences green plant regeneration from barley callus

The plant hormone ethylene is involved in numerous plant processes including in vitro growth and regeneration. Manipulating ethylene in vitro may be useful for increasing plant regeneration from cultured cells. As part of ongoing efforts to improve plant regeneration from barley (Hordeum vulgare L.), we investigated ethylene emanation using our improved system and investigated methods of manipulating ethylene to increase regeneration. In vitro assays of regeneration from six cultivars, involving 10 weeks of callus initiation and proliferation followed by 8 weeks of plant regeneration, showed a correlation between regeneration and ethylene production: ethylene production was highest from ‘Golden Promise’, the best regenerator, and lowest from ‘Morex’ and ‘DH-20’, the poorest regenerators. Increasing ethylene production by addition of 1-aminocyclopropane 1-carboxylic acid (ACC) during weeks 8–10 increased regeneration from Morex. In contrast, adding ACC to Golden Promise cultures during any of the tissue culture steps reduced regeneration, suggesting that Golden Promise may produce more ethylene than needed for maximum regeneration rates. Blocking ethylene action with silver nitrate during weeks 5–10 almost doubled the regeneration from Morex and increased the Golden Promise regeneration 1.5-fold. Silver nitrate treatment of Golden Promise cultures during weeks 8–14 more than doubled the green plant regeneration. These results indicate that differential ethylene production is related to regeneration in the improved barley tissue culture system. Specific manipulations of ethylene were identified that can be used to increase the green plant regeneration from barley cultivars. The timing of ethylene action appears to be critical for maximum regeneration.     

Free-living flatworms under the knife: past and present

Traditionally, regeneration research has been closely tied to flatworm research, as flatworms (Plathelminthes) were among the first animals where the phenomenon of regeneration was discovered. Since then, the main focus of flatworm regeneration research was on triclads, for which various phenomena were observed and a number of theories developed. However, free-living flatworms encompass a number of other taxa where regeneration was found to be possible. This review aims to display and to compare regeneration in all major free-living flatworm taxa, with special focus on a new player in the field of regeneration, Macrostomum lignano (Macrostomorpha). Findings on the regeneration capacity of this organism provide clues for links between regeneration and (post-)embryonic development, starvation, and asexual reproduction. The role of the nervous system and especially the brain for regeneration is discussed, and similarities as well as particularities in regeneration among free-living flatworms are pointed out.