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Xi Tan Yong-Zhen Gong Ping Wu Duan-Fang Liao Xi-Long Zheng 《International journal of molecular sciences》2014,15(8):14348-14363
Mesenchymal stem cells (MSCs) are multipotent stem cells that give rise to various cell types of the mesodermal germ layer. Because of their unique ability to home in on injured and cancerous tissues, MSCs are of great potential in regenerative medicine. MSCs also contribute to reparative processes in different pathological conditions, including cardiovascular diseases and cancer. However, many studies have shown that only a small proportion of transplanted MSCs can actually survive and be incorporated into host tissues. The effects of MSCs cannot be fully explained by their number. Recent discoveries suggest that microparticles (MPs) derived from MSCs may be important for the physiological functions of their parent. Though the physiological role of MSC-MPs is currently not well understood, inspiring results indicate that, in tissue repair and anti-cancer therapy, MSC-MPs have similar pro-regenerative and protective properties as their cellular counterparts. Thus, MSC-MPs represent a promising approach that may overcome the obstacles and risks associated with the use of native or engineered MSCs. 相似文献
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Nanosensors for Continuous and Noninvasive Monitoring of Mesenchymal Stem Cell Osteogenic Differentiation
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Christian Wiraja David C. Yeo Mark S. K. Chong Chenjie Xu 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(10):1342-1350
Assessing mesenchymal stem cell (MSC) differentiation status is crucial to verify therapeutic efficacy and optimize treatment procedures. Currently, this involves destructive methods including antibody‐based protein detection and polymerase chain reaction gene analysis, or laborious and technically challenging genetic reporters. Development of noninvasive methods for real‐time differentiation status assessment can greatly benefit MSC‐based therapies. This report introduces a nanoparticle‐based sensing platform that encapsulates two molecular beacon (MB) probes within the same biodegradable polymeric nanoparticles. One MB targets housekeeping gene glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) as an internal reference, while another detects alkaline phosphatase (ALP), a functional biomarker. Following internalization, MBs are gradually released as the nanoparticle degrades. GAPDH MBs provide a stable reference signal throughout the monitoring period (18 days) regardless of differentiation induction. Meanwhile, ALP mRNA undergoes well‐defined dynamics with peak expression observed during early stages of osteogenic differentiation. By normalizing ALP‐MB signal with GAPDH‐MB, changes in ALP expression can be monitored, to noninvasively validate osteogenic differentiation. As proof‐of‐concept, a dual‐colored nanosensor is applied to validate MSC osteogenesis on 2D culture and polycaprolactone films containing osteo‐inductive tricalcium phospate. 相似文献
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In order to reduce the stress shielding of the femur following Total Hip Arthroplasty (THA), stiffness matching strategies between the host bone and femoral stem still need to be investigated. Additive Layer Manufacturing (ALM) technologies such as Selective Laser Melting (SLM) can produce components from a single alloy with varying mechanical properties, and hence, functionally graded parts. This work considers the flexural characteristics of laser melted cobalt chrome femoral stems, by using a combination of mechanical testing and finite element analysis. A functionally graded design methodology was considered in order to reduce the weight and stiffness of the femoral stems. Three separate functionally graded designs were investigated by incorporating square pore cellular structures of varying density. The results confirmed that selective laser melting can repeatedly manufacture a functionally graded femoral stem that is 48% lighter and 60% more flexible than a traditional fully dense stem. However, there are concerns associated with the repeatability of the manufacturing process for producing stems with cellular structures that incorporate strut sizes, which are equal to or less than 0.5 mm. 相似文献
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当前新型冠状病毒肺炎(corona virus disease 2019, COVID-19)全球蔓延,全球累计确诊超过16 750万例。新型冠状病毒传播具有高传染性,人体感染后具有呼吸道症状、发热、严重呼吸综合征、器官衰竭,甚至死亡。对于COVID-19目前没有特异性治疗方法,大部分治疗方案采用的是对症支持治疗,但是预后差。间充质干细胞(mesenchymal stem cells, MSCs)不仅能够修复损伤的肺组织,还具有调控免疫、抗炎等作用,具有良好的临床应用前景。本文将对MSCs应用于新冠病毒肺炎治疗做一综述,以供同行参考。 相似文献
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Krzysztof Marycz Monika Marędziak Jakub Grzesiak Ryszard Fryczkowski Jadwiga Laska 《Polymer-Plastics Technology and Engineering》2016,55(18):1897-1907
Articular cartilage dysfunctions are major cause of pain and disability and lead to serious health complications. Cell-based therapies are proposed as treatment methods for cartilage regeneration. In this study, we proposed polyurethane/poly(L-lactide-co-D, L-lactide)-based electrospun nonwovens as carriers for the delivery of human adipose-derived stromal stem cells. We found that 6:4 and 8:2 polyurethane/poly(L-lactide-co-D, L-lactide) initially enhance proliferative rate of human adipose-derived stromal stem cells, shorten their population doubling time, promote creation of functional chondrogenic nodules during chondrogenic differentiation, improve the collagen-2-to-collagen-1 protein ratio, and upregulate the expression of collagen-2 and aggrecan genes. 相似文献
129.
15‐Methylene‐Eburnamonine Kills Leukemic Stem Cells and Reduces Engraftment in a Humanized Bone Marrow Xenograft Mouse Model of Leukemia
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Dr. Dilini C. Gunasekara Dr. Mary M. Zheng Tara Mojtahed Dr. James R. Woods Prof. Tamer E. Fandy Dr. Mark V. Riofski Prof. Carlotta A. Glackin Prof. Hazem E. Hassan Dr. Julia Kirshner Prof. David A. Colby 《ChemMedChem》2016,11(21):2392-2397
Recent studies suggest that leukemia stem cells (LSCs) play a critical role in the initiation, propagation, and relapse of leukemia. Herein we show that (?)‐15‐methylene‐eburnamonine, a derivative of the alkaloid (?)‐eburnamonine, is cytotoxic against acute and chronic lymphocytic leukemias (ALL and CLL) and acute myelogenous leukemia (AML). The agent also decreases primary LSC frequency in vitro. The cytotoxic effects appear to be mediated via the oxidative stress pathways. Furthermore, we show that the compound kills AML, ALL, and CLL stem cells. By the use of a novel humanized bone marrow murine model of leukemia (huBM/NSG), it was found to decrease progenitor cell engraftment. 相似文献
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