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Yang BC Lee NJ Im GS Seong HH Park JK Kang JK Hwang S 《Birth defects research. Part B, Developmental and reproductive toxicology》2011,92(3):224-230
Background: The composition and nutritional value of meat and milk derived from cloned animals and their progeny has not been demonstrated to be different from normal animals, but possible food consumption risks that might arise from unidentified hazards remain. In this study, we investigated the effects of somatic cell nuclear transfer cloned‐cattle meat diet on the behavioral and reproductive characteristics of F1 rats derived from dams that were also fed on cloned‐cattle meat. Methods and results: F1 rats were divided into five diet groups with their dams: commercial pellets (control), pellets containing 5% (N‐5) and 10% (N‐10) of normal‐cattle meat, and diets containing 5% (C‐5) and 10% (C‐10) of cloned‐cattle meat. In most cases, the cloned‐cattle meat diet did not affect body weight and food consumption in both male and female F1 rats during 11 weeks, except for significantly higher body weight in both N‐5 and N‐10 (3–5 weeks, p<0.05 or p<0.01) and significantly higher food consumption in the both normal‐ and cloned‐cattle meat groups (7–9 weeks, p<0.05 or p<0.01), as compared with the controls, respectively. We detected no signs of test substance‐related toxicities on organ weights and behavioral characteristics (sensory reflex, motor function, and spatial learning and memory tests). Reproductive functions did not significantly differ among all examined rats (mating, fertility, and implantation). Conclusions: These behavioral and reproductive toxicity results suggest that there are no obvious food safety concerns related to cloned‐cattle meat in these parameters. Birth Defects Res (Part B) 92:224–230, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
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体细胞核移植技术具有极其广阔的应用前景,但极低的成功率限制了这项技术在实践生产中的应用。不同的学者在不同的物种上进行了一系列的尝试,试图提高体细胞核移植的成功率。本文就体细胞核移植技术在不同物种中的成功应用进行阐述,并就如何提高体细胞核移植成功率阐明一些观点。 相似文献
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哺乳动物体细胞核移植技术在农业、生物技术、医药生产和濒危动物保护等方面具有很大的潜力和应用价值,已成为目前发育生物学研究的重要方法。但是核重编程仍是核移植技术的关键因素,制约了重构胚胎干细胞的研究。只有供核发生完全重编程,重构胚胎才能正常发育。核重编程与供核者的年龄,供核细胞的组织来源、分化状态、细胞周期、传代次数,供核细胞的表观遗传标记以及供卵者的年龄、卵子的成熟度等因素有关。创造各种适于核重编程的条件有利于从更高的起点开展核移植胚胎干细胞的研究,提高重枸胚胎干细胞建系效率。 相似文献
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GONG Guochun* DAI Yunping* ZHU Huabing WANG Haiping WANG Lili LI Rong WAN Rong LIU Ying & LI Ning . State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China . Institute of Animal Science Chinese Academy of Agricultural Science Beijing China 《中国科学:生命科学英文版》2004,47(5):470-476
Remarkable progress has been made in animal cloning research since the first mammal was success-fully cloned[1], and the technique of SCNT is now widely used in biological studies. In theory, successful development of live offspring from SCNT embryos demonstrates that a fully differentiated somatic cell can be reprogrammed and restore its totipotency; in practice, animal cloning can be applied for duplication of elite animals, production of transgenic animals, rescue of endangered species … 相似文献
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Six types of bovine somatic cell lines, including a granulosa cell line of Chinese red-breed yellow cattle (YGR), a granulosa
cell line of Holstein cow (HGR), two skin fibroblast cell lines of two adult Holstein cows respectively (AFB1 and AFB2), a
skin fibroblast cell line (FFB) and an oviduct epithelial cell line (FOV) of a Holstein fetus, were established. Somatic cell
nuclear transfer (SCNT) was carried out using these cells as nuclei donor, and a total of 12 healthy calves were cloned. The
effects of different types of donor cells on developmental potential of bovine SCNT embryos were investigated, (i) There was
no significant difference in development rates to the blastocyst stage for SCNT embryos from YGR and HGR (33.2% and 35.1%,
respectively). Pregnancy rates of them were 33.3% and 30.2%, respectively; and birth rates were 16.7% and 11.6%, respectively,
(ii) Development rates to the blastocyst stage for SCNT embryos from diffetent individuals (AFB1 and AFB2) differed significantly
(27.9% and 39.4%, respectively, P < 0.05). Pregnancy rates of them were 36.2% and 36.4%, respectively; and birth rates were
14.9 % and 27.3%, respectively, (iii) There was significant difference in development rates to the blastocyst stage for SCNT
embryos from FFB and FOV of the same fetus (37.9% and 41.5%, respectively,P < 0.05). Pregnancy rates of them were 45.7% and 24.1%, respectively; and birth rates were 22.9 % and 10.3%, respectively.
Finally, developmental potential of bovine SCNT embryos from all four types of somatic cells from Holstein cows (HGR, AFB,
FFB and FOV) were compared. Forin vitro development stage, development rates to the blastocyst stage for SCNT embryos from HGR, AFB, FFB and FOV were 35.1%A, 29.4%B, 37.9%A and 41.5%C, respectively (P
ABC < 0.05); forin vivo development stage, pregnancy rates of them were 30.2%, 36.2%, 45.7% and 24.1%, respectively; and birth rates of them were
11.6%, 17.2%, 22.9% and 10.3% respetively. 相似文献
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In this study we investigated spontaneous oocyte activation and developmental ability of rat embryos of the SD-OFA substrain. We also tried to improve the somatic cell nuclear transfer (SCNT) technique in the rat by optimizing methods for the production of reconstructed embryos. About 20% of oocytes extruded the second polar body after culture for 3 hr in vitro and 84% of oocytes were at the MII stage. MG132 blocked spontaneous activation but decreased efficiency of parthenogenetic activation. Pronuclear formation was more efficient in strontium-activated oocytes (66.1-80.9%) compared to roscovitine activation (24.1-54.5%). Survival rate after enucleation was significantly higher (89.4%) after slitting the zona pellucida and then pressing the oocyte with a holding pipette in medium without cytochalasin B (CB) compared to the conventional protocol using aspiration of the chromosomes after CB treatment (67.7%). Exposure of rat ova to UV light for 30 sec did not decrease their in vitro developmental capacity. Intracytoplasmic cumulus cell injection dramatically decreased survival rate of oocytes (42%). In contrast, 75.9% of oocytes could be successfully electrofused. Development to the 2-cell stage was reduced after SCNT (24.6% compared 94.6% in controls) and none from 244 reconstructed embryos developed in vitro beyond this stage. After overnight in vitro culture, 74.4% of the SCNT embryos survived and 56.1% formed pronuclei. The pregnancy rate of 33 recipients after the transfer of 695 of these cloned embryos was, however, very low (18.2%) and only six implantation sites could be detected (0.9%) without any live fetuses and offspring. 相似文献
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细胞核重编程是哺乳动物正常受精胚胎和克隆胚胎发育过程中的一个重要特性,主要是对表观遗传学特征进行重新编写,包括染色质重塑、组蛋白修饰、DNA甲基化、印记基因表达、X染色体失活等表观遗传修饰的改变。通过细胞核重编程,首先,受精卵和克隆胚胎的供体核停止其特有的基因表达程序,恢复为全能状态的基因表达程序;然后,受精胚胎和克隆胚胎的细胞再从全能状态重新进入分化状态,最终形成各种组织和器官。近年来,不少研究表明,克隆胚胎的细胞核重编程存在不同程度的表观遗传修饰异常,可能对克隆及其农业和医学应用有着重要影响。本文就正常和克隆胚胎细胞核重编程的研究进展以及克隆胚胎的细胞核重编程异常对克隆的影响作一综述,并对目前有关治疗性克隆前景的不同看法进行了讨论。 相似文献
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Jingjuan Ji Tonghang Guo Xianhong Tong Lihua Luo Guixiang Zhou Yingyun Fu Yusheng Liu 《生物学前沿》2007,2(1):80-84
Therapeutic cloning,which is based on human somatic cell nuclear transfer,is one of our major research objectives.Though inter-species nuclear transfer has been introduced to construct human somatic cell cloned embryos,the effects of type,passage,and preparation method of donor cells on embryo development remain unclear.In our experiment,cloned embryos were reconstructed with different passage and preparation methods of ossocartilaginous cell,skin fibroblast,and cumulus cells.The cumulus cell embryos showed significantly higher development rates than the other two (P<0.05).The development rate of embryos reconstructed with skin fibroblasts of different passage number and somatic cells of different chilling durations showed no significant difference.Also,fluorescence in situ hybridization (FISH)was conducted to detect nuclear derivation of the embryos.The result showed that the nuclei of the inter-species cloned embryo cells came from human.We conclude that (1)cloned embryos can be constructed through human-rabbit interspecies nuclear transfer;(2)different kinds of somatic cells result in different efficiency of nuclear transfer,while in vitro passage of the donor does not influence embryo development;(3)refrigeration is a convenient and efficient donor cell preparation method.Finally,it is feasible to detect DNA gcnotype through FISH. 相似文献
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Ji Jingjuan Guo Tonghang Tong Xianhong Luo Lihua Zhou Guixiang Fu Yingyun Liu Yusheng 《Frontiers of Biology in China》2007,2(1):80-84
Therapeutic cloning, which is based on human somatic cell nuclear transfer, is one of our major research objectives. Though
inter-species nuclear transfer has been introduced to construct human somatic cell cloned embryos, the effects of type, passage,
and preparation method of donor cells on embryo development remain unclear. In our experiment, cloned embryos were reconstructed
with different passage and preparation methods of ossocartilaginous cell, skin fibroblast, and cumulus cells. The cumulus
cell embryos showed significantly higher development rates than the other two (P < 0.05). The development rate of embryos reconstructed with skin fibroblasts of different passage number and somatic cells
of different chilling durations showed no significant difference. Also, fluorescence in situ hybridization (FISH) was conducted to detect nuclear derivation of the embryos. The result showed that the nuclei of the
inter-species cloned embryo cells came from human. We conclude that (1) cloned embryos can be constructed through human-rabbit
interspecies nuclear transfer; (2) different kinds of somatic cells result in different efficiency of nuclear transfer, while
in vitro passage of the donor does not influence embryo development; (3) refrigeration is a convenient and efficient donor
cell preparation method. Finally, it is feasible to detect DNA genotype through FISH.
Translated from Zoological Research, 2005, 26(4): 416–421 [译自: 动物学研究] 相似文献
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Stem cell research in China 总被引:2,自引:0,他引:2
Liao L Li L Zhao RC 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1482):1107-1112
In the past 5 years, China has increased its efforts in the field of stem cell research and practice. Basic research mainly focuses on bone marrow and embryonic stem cells. Clinical applications of stem cells in the treatment of acute heart failure, acute liver failure and lower limb ischaemia have been reported by many hospitals. China enacted its 'Ethical Guidelines for Human Embryonic Stem Cell Research' in 2003. At present, China has the most liberal and favourable environments for human embryonic stem cell research. 相似文献
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Quanli An Wei Peng Yuyao Cheng Zhenzhen Lu Chuan Zhou Yong Zhang Jianmin Su 《Journal of cellular physiology》2019,234(10):17370-17381
Oocyte quality, which is directly related to reprogramming competence, is a major important limiting factor in animal cloning efficiency. Compared with oocytes matured in vivo, in vitro matured oocytes exhibit lower oocyte quality and reprogramming competence primarily because of their higher levels of reactive oxygen species. In this study, we investigate whether supplementing the oocyte maturation medium with melatonin, a free radical scavenger, could improve oocyte quality and reprogramming competence. We found that 10−9 M melatonin effectively alleviated oxidative stress, markedly decreased early apoptosis levels, recovered the integrity of mitochondria, ameliorated the spindle assembly and chromosome alignment in oocytes, and significantly promoted subsequent cloned embryo development in vitro. We also analyzed the effects of melatonin on epigenetic modifications in bovine oocytes. Melatonin increased the global H3K9 acetylation levels, reduced the H3K9 methylation levels, and minimally affected DNA methylation and hydroxymethylation. Genome-wide expression analysis of genes in melatonin-treated and nontreated oocytes was also conducted by high-throughput RNA sequencing. Our results indicated that melatonin ameliorates oocyte oxidative stress and improves subsequent in vitro development of bovine cloned embryos. 相似文献
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体细胞核移植技术是指将一个分化的体细胞核置入去核的卵母细胞中,并发育产生与供体细胞遗传背景一致的克隆后代的技术。目前,世界上通过体细胞核移植技术已经产生了许多的克隆动物。但克隆过程中还存在着很多问题,比如,克隆效率太低、克隆个体常伴有表型异常和早亡等,从而使该技术应有的应用潜力不能得到充分的发挥。体细胞表观遗传学重编程的不完全或紊乱是造成核移植诸多问题的主要原因。近十多年来,人们对体细胞核移植后的重编程进行了广泛的研究,其核心内容包括核及核外结构的重塑、DNA甲基化模式的重建、基因印迹和x染色体失活、组蛋白乙酰化模式的重建、端粒长度恢复等,以期能够对其重编程加以人为干预,从而提高动物克隆效率。本文拟对体细胞核移植诱导的重编程研究进展加以综述,希望对体细胞重编程机制的阐明有所启发。 相似文献
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体细胞重编程与microRNAs(miRNAs)均为近年来研究的热点问题。到目前为止,能成功诱导体细胞形成多能性干细胞的体细胞重编程方法有核移植(nuclear transfer,NT)和外源因子诱导形成多能干细胞(induced pluripotent stem cells,iPSc)两种,这两种方法让人们看到了体细胞重编程在细胞治疗方面具有诱人的应用前景。miRNAs是真核生物中存在的一类长度为22nt左右起调控作用的内源性非编码RNA,它在转录后水平调节靶基因的表达,是细胞内基因表达的基本调控机制之一。近年的研究结果表明,miRNAs在干细胞干性维持和分化过程中具有重要的调节作用,从miRNAs角度研究体细胞重编程机理将对体细胞重编程的应用具有重要意义。 相似文献
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供体细胞与哺乳动物体细胞核移植 总被引:1,自引:0,他引:1
哺乳动物体细胞核移植(克隆)技术在转基因动物生产、珍稀动物资源复原与保护、生物学基础研究等方面业已显示出重要的应用价值,而目前该技术还与诱导多能干细胞技术一同被认为是创制患者特异性多能干细胞,为再生医学临床"细胞治疗"提供素材的最佳手段。但是,体细胞克隆的效率仍不理想,关键机制还不清楚,严重制约了该技术的推广。因此,如何提高克隆效率已成为人们普遍关心的首要问题。在体细胞克隆技术所涉及的各环节中,供体细胞是影响克隆效率的最关键因素之一。该文从供体细胞的生物学因素和技术因素两方面进行了回顾,旨在为进一步探寻建立物种或供体细胞个性化准备方案,为提高动物克隆效率提供参考。 相似文献
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Alexander B Coppola G Perrault SD Peura TT Betts DH King WA 《Molecular reproduction and development》2007,74(12):1525-1537
This study was carried out to determine the telomere length status of sheep clones and their offspring, and to examine telomere dynamics and chromosomal abnormalities in culture propagated donor cells. Skin samples were collected from somatic cell nuclear transfer-derived sheep clones, and three of their progeny generated by natural mating. Samples were collected from control animals (n = 35), spanning in age from 1 month to 36 months of age. Genomic DNA was extracted from cell/tissue samples and their telomere lengths were assessed by terminal restriction fragment (TRF) analysis. Results revealed: that (a) sheep clones derived from cultured somatic cells have shortened telomere lengths compared to age-matched controls; (b) the offspring derived from natural mating between clones had normal telomere lengths compared to their age-matched counterparts; and donor cell cultures beyond 20 population doublings had significantly (P < 0.05) shortened telomeres and exhibited a higher numerical and structural chromosomal abnormalities. 相似文献
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Jing Fu Pengfei Guan Leiwen Zhao Hua Li Shuzhen Huang Fanyi Zeng Yitao Zeng 《遗传学报》2008,35(5):273-278
The donor cells from different individuals and with different foreign genes introduced were investigated to determine their effects on the efficiency of somatic cell nuclear transfer (SCNT). The bovine ear fibroblast from different individuals was isolated, cultured, and then transfected with foreign genes to establish the stable cell lines, which were used as donor cells for nuclear transfer. The ooeytes were obtained through ovum pick up operation. After in vitro maturation, the M II phase oocytes were selected as receptors for nuclear transfer.The reconstructed embryos were cultured in vitro and observed at 2 h, 48 h, and 7 days after transfer to assess the rate of fusion using cleaved and blastoeyst as the parameters of SCNT efficiency. The donor cells from different individuals (04036, 06081, 06088, and 06129)had no obvious effect on the fusion and cleaved rate, whereas there was significant difference in the blastocyst rate (P<0.05), and the rate was 62.3%, 37.0%, 35.1%, and 15.6%, respectively. There was no significant difference among the rate of fusion, cleaved and blastocyst in donor cells with different foreign genes (P>0.05). It was concluded that the genetic background of the donor cells could affect the effi-ciency of SCNT, while the introduction of foreign genes into the donor cells had no obvious effect on the efficiency. This study provides useful information for the SCNT and would benefit in promoting the efficiency. 相似文献