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991.
Cost of adaptation to a metalliferous environment for Thlaspi caerulescens: a field reciprocal transplantation approach 总被引:1,自引:1,他引:0
Dechamps C Noret N Mozek R Escarré J Lefèbvre C Gruber W Meerts P 《The New phytologist》2008,177(1):167-177
Field reciprocal transplantations of two metallicolous populations (Mpops) and two nonmetallicolous populations (NMpops) of Thlaspi caerulescens were performed here to determine the pattern of local adaptation and to assess the cost of adaptation of Mpops to a metalliferous environment (Menv). The role of herbivores as an important selective pressure in the nonmetalliferous environment (NMenv) was also examined. Growth, survival, fitness, life cycle and herbivore consumption were monitored for each transplant for 2 yr. Local adaptation of Mpops to their own environment was clearly demonstrated, as Mpops consistently outperformed NMpops in Menv. In NMenv, no advantage of NMpops over Mpops was detected. However, the fitness of Mpops was generally lower in NMenv than in Menv. Herbivore consumption appeared to be a significant selective pressure for Mpops in NMenv. An imbalance of selective forces between Menv and NMenv probably explains the greater local adaptation of Mpops. Therefore, colonization of NMenv by Mpops appears possible. Although Mpops were able to survive and reproduce in NMenv, they nevertheless expressed a cost attributable in part to their higher susceptibility to herbivores. 相似文献
992.
Ming-Fang Wang You-Bing Li Xiao-Juan Gao Hao-Yang Zhang Su Lin Yue-Yong Zhu 《World journal of stem cells》2018,10(10):138-145
AIM To evaluate the long-term efficacy and safety of autologous stem cell transplantation(SCT) for decompensated liver cirrhosis.METHODS Consecutive patients with decompensated liver cirrhosis were included and assigned into the SCT group and non-transplantation(non-SCT) group according to whether they received SCT treatment. Patients werefollowed up for ten years. The long-term survival rate and incidence of hepatocellular carcinoma(HCC) were compared between groups. 相似文献
993.
Qiwang Ma Yu Ma Xiaotian Dai Tao Ren Yingjie Fu Wenbin Liu Yufei Han Yingchuan Wu Yu Cheng Ting Zhang Wei Zuo 《蛋白质与细胞》2018,9(3):267
Irreversible destruction of bronchi and alveoli can lead to multiple incurable lung diseases. Identifying lung stem/progenitor cells with regenerative capacity and utilizing them to reconstruct functional tissue is one of the biggest hopes to reverse the damage and cure such diseases. Here we showed that a rare population of SOX9+ basal cells (BCs) located at airway epithelium rugae can regenerate adult human lung. Human SOX9+ BCs can be readily isolated by bronchoscopic brushing and indefinitely expanded in feeder-free condition. Expanded human SOX9+ BCs can give rise to alveolar and bronchiolar epithelium after being transplanted into injured mouse lung, with air-blood exchange system reconstructed and recipient’s lung function improved. Manipulation of lung microenvironment with Pirfenidone to suppress TGF-β signaling could further boost the transplantation efficiency. Moreover, we conducted the first autologous SOX9+ BCs transplantation clinical trial in two bronchiectasis patients. Lung tissue repair and pulmonary function enhancement was observed in patients 3–12 months after cell transplantation. Altogether our current work indicated that functional adult human lung structure can be reconstituted by orthotopic transplantation of tissue-specific stem/progenitor cells, which could be translated into a mature regenerative therapeutic strategy in near future. 相似文献
994.
帕金森病(Parkinson's disease, PD)是由于黑质中多巴胺能神经元(dopaminergic neurons, DAns)的病变导致多巴胺含量降低而引起的一种神经退行性疾病,其发病机制尚不明确,而且临床缺乏有效的早期诊断和治疗手段。诱导多能干细胞(induced pluripotent stem cells, iPSCs)的出现为神经系统疾病特别是神经退行性疾病的治疗带来了希望。基于iPSCs的细胞模型可以广泛开展PD发病机制的研究,同时以iPSCs来源的DAns、神经干细胞(neural stem cells, NSCs)等的细胞移植治疗,更是未来PD治疗最有希望的手段。从基于iPSCs的不同基因突变类型的细胞模型与不同分化程度的细胞移植治疗两个方面介绍诱导多能干细胞在PD研究中的进展,旨在分析诱导多能干细胞在帕金森病方面的应用及不足。 相似文献
995.
Pre‐conditions for eliminating mitochondrial dysfunction and maintaining liver function after hepatic ischaemia reperfusion 下载免费PDF全文
The liver, the largest organ with multiple synthesis and secretion functions in mammals, consists of hepatocytes and Kupffer, stem, endothelial, stellate and other parenchymal cells. Because of early and extensive contact with the external environment, hepatic ischaemia reperfusion (IR) may result in mitochondrial dysfunction, autophagy and apoptosis of cells and tissues under various pathological conditions. Because the liver requires a high oxygen supply to maintain normal detoxification and synthesis functions, it is extremely susceptible to ischaemia and subsequent reperfusion with blood. Consequently, hepatic IR leads to acute or chronic liver failure and significantly increases the total rate of morbidity and mortality through multiple regulatory mechanisms. An increasing number of studies indicate that mitochondrial structure and function are impaired after hepatic IR, but that the health of liver tissues or liver grafts can be effectively rescued by attenuation of mitochondrial dysfunction. In this review, we mainly focus on the subsequent therapeutic interventions related to the conservation of mitochondrial function involved in mitigating hepatic IR injury and the potential mechanisms of protection. Because mitochondria are abundant in liver tissue, clarification of the regulatory mechanisms between mitochondrial dysfunction and hepatic IR should shed light on clinical therapies for alleviating hepatic IR‐induced injury. 相似文献
996.
997.
Induction of xenogeneic islet transplantation tolerance by simultaneously blocking CD28-B7 and OX40-OX40L co-stimulatory pathways 总被引:3,自引:0,他引:3
WANG Guangming FENG Yougang HAO Jie LI Ailing GAO Xiang & XIE Shusheng Department of Immunology Peking University Health Science Center Beijing China 《中国科学:生命科学英文版》2005,48(5):515-522
Type 1 diabetes mellitus is an autoimmune disease caused by T cell-mediated destruction of pancreatic beta islets. With its incidence continuous rising in the pediatric age group in recent years, it is becoming a serious threat to the human health. Up to now, there has been no effective therapy for diabetes mellitus, and islet transplantation still remains a promising ap-proach to the treatment of Type 1 diabetes. However, two serious problems hinder the successful islets transplantation, tha… 相似文献
998.
D. Link A. Irintchev U. Knauf A. Wernig A. Starzinski-Powitz 《Experimental cell research》2001,270(2):138-150
The aim of this work was to introduce a tetracycline-responsive (Tet-off) gene expression system into myoblasts in order to regulate a reporter gene not only in vitro but also particularly in muscles implanted with these engineered myoblasts. Mouse myoblasts from a long-term culture (i28 cells) were transfected initially to generate and characterize two stable master clones expressing tetracycline-responsive transactivator protein tTA. Like parental i28 myoblasts, these clones differentiated well in vitro. The second step introduced the firefly (Photinus pyralis) luciferase gene into one of the stable tTA clones producing double transfectants expressing luciferase in the absence of tetracycline. Addition of tetracycline (1 microg ml(-1)) resulted in at least 100-fold decreases in luciferase activity within 8 h in both growing and differentiating myoblast cultures. Enzyme activity was rapidly restored after tetracycline was removed (8 h). After successful implantation of these myoblasts into damaged mouse muscles, luciferase expression in the matured progeny cells could be regulated by oral application of doxycycline for at least 1 month. The tetracycline-responsive master clones are potentially powerful tools for studying the function of various genes in postnatal myogenesis. 相似文献
999.
目的探讨阿尔茨海默病(AD)模型鼠双侧海马区移植含多因子孵育的神经祖细胞(NPCs)后记忆认知功能改善情况及NPCs移植后迁移定位和分化能力。
方法取胎龄10?d的C57BL/6J孕鼠,分离得胎鼠NPCs,NPCs体外分化及鉴定,AD模型鼠分3组:NPCs+因子组、因子组及PBS组,对照组为同月龄C57BL/6J小鼠;Morris水迷宫及新物体识别实验检测AD模型鼠移植NPCs细胞前,及移植1至6个月后记忆行为变化情况;通过免疫荧光,免疫组化和Western-blot检测海马区移植的NPCs向神经元和胆碱能神经元分化及迁移能力。组间比较采用F检验。
结果Morris水迷宫实验中,NPCs+因子组找到平台前的逃避潜伏期时间(14.12±7.45)s要明显低于注射PBS的AD模型鼠组[(39.65±4.64)?s,F = 2.578,P = 0.0094],因子组时间(15.68±5.34)s同样低于PBS组[(39.65±4.64)s,F?= 1.324,P = 0.0016],24 h撤去平台后,NPCs+因子组逃避潜伏期时间(15.12±3.52)s仍低于PBS组[(37.17±2.18)?s,F = 2.598,P = 0.0003],因子组时间(16.62±3.23)s同样低于PBS组[(37.17±2.18)s,F = 2.186,P = 0.0004)];新物体识别实验中,各实验组对新物体探究时间占总探究时间百分比结果中,NPCs+因子组(68.46±2.4)%要高于PBS组[(54.47±4.79)%,F =3.983,P = 0.018],因子组(65.20±1.03)%同样高于PBS组[(54.47±4.79)%,F = 21.63,P = 0.042];实验结果表明,通过移植细胞与因子AD模型鼠的记忆认知功能在早期均得到改善,随着时间的增长,移植NPCs组的记忆改善情况持续时间更长久;Western blot结果显示AD模型鼠海马区胆碱能神经元与正常C57BL/6J鼠相比表达减少,移植NPCs后,AD模型鼠脑内胆碱能神经元增多;免疫荧光与免疫组化结果显示,移植的NPCs在AD模型鼠脑内移植区存活,并向胆碱能神经元分化。
结论AD模型鼠双侧海马区移植的含多因子孵育的NPCs,通过分化成功能性的胆碱能神经元来改善AD鼠的记忆认知功能。 相似文献
1000.