利用斑马鱼模型研究芦笋有效成分对免疫功能的调节作用

采用正常发育48 hpf的转基因斑马鱼为实验动物,以氯霉素处理引起免疫抑制,分别加入25.0~200.0 mg/L的芦笋多糖、6.25~100.00 mg/L的芦笋皂苷,处理24 h,观察各组斑马鱼的发育情况,拍照并统计斑马鱼体内中性粒细胞的数量。结果表明,氯霉素处理斑马鱼后,斑马鱼体内中性粒细胞数量减少,芦笋多糖在浓度为50.0~200.0 mg/L范围内对斑马鱼体内中性粒细胞数量减少具有明显改善作用,且具有明显的剂量依赖效应;芦笋皂苷在实验剂量范围内均显示出显著的改善作用。实验结果显示,芦笋的有效成分芦笋多糖、芦笋皂苷对斑马鱼免疫功能具有明显的调节作用。     

酪氨酸酶抑制法与斑马鱼评价模型的比较研究

传统的酪氨酸酶抑制法与新型的斑马鱼评价模型之间是否存在优势互补,斑马鱼模型是否具有广泛适用性,这两个问题对美白剂评价方法的发展具有较大的意义.采用酪氨酸酶抑制法和斑马鱼评价模型同时评价常用美白剂包括曲酸、熊果苷、抗坏血酸、光甘草定和氢醌的美白作用.结果证明,用这两种方法评价曲酸和熊果苷都呈现阳性反应,说明两种方法具有一致性;但是,抗坏血酸和光甘草定在酪氨酸酶活性抑制法中显示出抑制作用,但对斑马鱼色素的形成并没有明显的抑制,这又说明两种方法具有矛盾性.酪氨酸酶抑制法能够阐述美白作用的机制包括单酚酶抑制和双酚酶抑制,而斑马鱼评价模型却能够评价美白剂的安全性包括致畸率和死亡率.总之,两种评价方法各具优缺点,两种方法的联合应用能够在美白剂的评价上实现优势互补.     

The effects of time of equilibration with cryoprotectants at 0°C prior to freezing on the survival of mouse embryos frozen by the two-step method

Summary Mouse embryos were frozen by the two-step method after equilibration for 0.1–60 min with cryoprotectants at 0°C. No survival or a very low survival was obtained after equilibration for only 0.1 min. The morulae showed the highest survival rates when equilibration time was 5–30 min with 2 M DMSO, 20–30 min with 2 M glycerol, 5–10 min with 2 M ethylene glycol and 20–30 min with 2 M propylene glycol, respectively.     

Evidence for reopening of the cranial neural tube in mouse embryos treated with cadmium chloride

Summary Use of the whole-embryo culture technique resulted in experiemtal evidence that the pathogenesis of exencephaly in mouse embryos after cadmium chloride treatment results from reopening of the cranial neural tube.     

Erythropoietins from teleosts

The epo genes of many teleosts, including zebrafish, have been cloned following the first identification of nonmammalian EPO from fugu in 2004. The zebrafish (Danio rerio) animal model is well suited for both developmental and genetic analyses for studying vertebrate erythropoiesis. The purpose of this review is to provide an update of recent progress in research on teleost EPO with a focus on its structure, expression and secretion. The EPO receptor and the downstream JAK/STAT signaling pathway are also discussed. Received 29 April 2008; received after revision 23 June 2008; accepted 25 June 2008     

The Expression of vasa Gene during Zebrafish （Danio rerio） Oogenesis

Vasa gene expression pattern during oogenesis of zebrafish was examined using in situ hybridization and fluorescent quantitative RT-PCR During zebrafish oogensis, vasa mRNA is expressed strongly and uniformly distributed in the cytoplasm in stage Ⅱ oocytes, followed by a distribution among vacuome in stage Ⅲ. Later in stage Ⅳ and Ⅴ, vasa mRNA is enriched at the cortex and finally localized at the cortex. The fluorescent quantitative RT-PCR shows that the quantity of vasa mRNA decreases from stage Ⅱ to stage Ⅲ, but remains relatively invariable from stage Ⅲ to stage Ⅴ. The observed differences in vasa mRNA expression in the different stages of zebrafish oogenesis suggest that vasa gene plays an important role during oogenesis.     

原核显微注射产生转基因绵羊胚胎

体外采集绵羊卵丘卵母细胞复合体,成熟培养24 h,经过体外受精培养17 h,比较高速离心对胚胎发育的影响;高速离心可以使黑色脂滴甩到一边从而使受精卵原核清晰可见.然后将绵羊乳腺特异表达人肝细胞再生增强因子和真核细胞表达增强绿色荧光蛋白(Enhanced Green fluorescence protein,EGFP)的载体DNA显微注射于绵羊受精卵雄原核中,并将异构胚在SOF液中发育培养.结果表明:高速离心组囊胚率低于对照组,但是没有显著性差异(P》0.05);显微注射外源基因2天后在激光共聚焦显微镜下可见荧光胚胎;PCR检测5个荧光胚胎均可见特异性条带.在原核显微注射生产转基因胚胎中,绿色荧光蛋白可作为标记基因进行早期胚胎筛选,为提高转基因动物移植效率奠定实验基础.     

Developmental sequence of Cambrian embryo Markuelia

Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.     

微注射人TCP10L基因对斑马鱼形态的影响

利用模式生物斑马鱼,通过微注射的方法,研究了人肝脏特异性转录因子TCP10L对斑马鱼早期胚胎发育的影响.结果显示:人TCP10L基因对斑马鱼胚胎发育有一定的毒性.表现为早期的脊索发育异常,个体严重畸形;当血液循环出现后,表现为血流延缓和围心腔水肿等症状.该项研究表明:人肝脏特异性转录因子TCP10L在斑马鱼胚胎中的过表达会引起显著的形态异常和心血管障碍,并且这种影响与其是否在斑马鱼肝内的特异表达有关,为进一步探明该转录因子在人肝脏内发挥的功能奠定了基础.     

稻瘟病菌粗毒素对水稻成熟胚愈伤组织诱导的影响及抗性筛选

利用稻瘟病不同生理小种菌株的液体培养提取的粗毒素对水稻成熟胚进行处理,粗毒素液对水稻胚芽的生长和胚的诱导有严重的抑制作用,与对照相比差异性极显著;不同浓度的粗毒素提取液其作用效果不同,随着毒素浓度的增大或是作用时间性的延长,水稻诱导受到的抑制作用越强。水稻成熟胚组织培养中进行抗稻瘟病菌突变体筛选的毒素浓度在30%较好;浸泡水稻成熟胚以处理72h愈伤诱导和分化效果较好;在进行抗稻瘟病突变体筛选中,以用含毒素的培养基进行诱导愈伤的处理的筛选取效果较好。