期刊文献+
共找到25,392篇文章
< 1 2 250 >
每页显示 20 50 100
M-CORD下无线接入网络资源分配研究 被引量:75
1
作者 王楚捷 王好贤 《计算机工程与应用》 CSCD 北大核心 2018年第22期92-98,共7页
针对M-CORD架构将传统的无线接入网络解耦并虚拟化的特征,考虑软件定义网络(SDN)的集中控制和全局监测作用,研究无线接入网侧资源的动态分配及优化问题。将数据中心的计算资源纳为资源分配考虑因素之一,综合干扰阈值、前传网络容量限制... 针对M-CORD架构将传统的无线接入网络解耦并虚拟化的特征,考虑软件定义网络(SDN)的集中控制和全局监测作用,研究无线接入网侧资源的动态分配及优化问题。将数据中心的计算资源纳为资源分配考虑因素之一,综合干扰阈值、前传网络容量限制、用户移动性、服务最低资源保障以及计算资源限制五方面,推导出M-CORD架构下无线接入网资源分配公式,通过改进基于增量的贪心分配算法,求得资源分配的次优解。仿真结果验证了改进算法在M-CORD架构下对无线接入网资源分配的适用性。 展开更多
关键词 M-cord 无线接入网络(RAN) 资源分配 干扰控制
下载PDF
Influence of patients' age on functional recovery after transplantation of olfactory ensheathing cells into injured spinal cord injury 被引量:60
2
作者 黄红云 陈琳 +11 位作者 王洪美 修波 李炳辰 王锐 张健 张峰 顾征 李荧 宋英伦 郝伟 潘树义 孙君昭 《Chinese Medical Journal》 SCIE CAS CSCD 2003年第10期1488-1491,共4页
Objective To evaluate the restoration of function after spinal cord injury (SCI) in patients of different ages who have underwent intraspinal transplantation of olfactory ensheathing cells (OECs). Methods One hundred ... Objective To evaluate the restoration of function after spinal cord injury (SCI) in patients of different ages who have underwent intraspinal transplantation of olfactory ensheathing cells (OECs). Methods One hundred and seventy-one SCI patients were included in this study. Of them,139 were male and 32 were female,with age ranging from 2 to 64 years (mean,34.9 years). In all SCI patients the lesions were injected at the time of operation with OECs. According to their ages,the patients were divided into 5 groups: ≤20 years group (n=9),21-30 years group (n=54),31-40 years group (n=60),41-50 years group (n=34) and>51 years group (n=14). The spinal cord function was assessed based on the American Spinal Injury Association (ASIA) Classification System before and 2-8 weeks after OECs transplantation. One-way ANOVA and q test were used for statistical analysis,and the data were expressed as mean±SD. Results After surgery,the motor scores increased by 5.2±4.8,8.6±8.0,8.3±8.8,5.7±7.3 and 8.2±7.6 in 5 age groups respectively ( F =1.009,P =0.404); light touch scores increased by 13.9±8.1,15.5±14.3,12.0±14.4,14.1±18.5 and 24.8±25.3 respectively ( F =1.837,P =0.124); and pin prick scores increased by 11.1±7.9,17.2±14.3,13.2±11.8,13.6±13.9 and 25.4±24.3 respectively ( F =2.651,P =0.035). Restoration of pin prick in >51 years group was better than other age groups except 21-30 years group. Conclusion OECs transplantation can improve the neurological function of spinal cord of SCI patients regardless of their ages. Further research into the long-term outcomes of the treatment will be required. 展开更多
关键词 cell transplantation · spinal cord injury · function recovery
原文传递
The regulation of the Treg/Th 17 balance by mesenchyma stem cells in human systemic lupus erythematosus 被引量:47
3
作者 Dandan Wang Saisai Huang +5 位作者 Xinran Yuan Jun Liang Renju Xu Genhong Yao Xuebing Feng Lingyun Sun 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2017年第5期423-431,共9页
Background and objective: Umbilical cord (UC)-derived mesenchymal stem cells (MSCs) have shown immunoregulation of various immune cells. The aim of this study was to investigate the mechanism of UC MSCs in the re... Background and objective: Umbilical cord (UC)-derived mesenchymal stem cells (MSCs) have shown immunoregulation of various immune cells. The aim of this study was to investigate the mechanism of UC MSCs in the regulation of peripheral regulatory T cells (Treg) and T helper 17 (Th17) cells in patients with systemic lupus erythematosus (SLE). Methods: Thirty patients with active SLE, refractory to conventional therapies, were given UC MSCs infusions. The percentages of peripheral blood CD4+CD25+Foxp3+ regulatory T cells (Treg) and CD3+CD8-1L17A+ Th17 cells and the mean fluorescence intensities (MFI) of Foxp3 and IL- 17 were measured at I week, I month, 3 months, 6 months, and 12 months after MSCs transplantation (MSCT). Serum cytokines, including transforming growth factor beta (TGF-β), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and IL-17A were detected using ELISA. Peripheral blood mononuclear cells from patients were collected and co-cultured with UC MSCs at ratios of 1:1, 10:1, and 50:1, respectively, for 72 h to detect the proportions of Treg and Th17 cells and the MFIs of Foxp3 and IL-17 were determined by flow cytometry. The cytokines in the supernatant solution were detected using ELISA. Inhibitors targeting TGF-β, IL-6, indoleamine 2,3-dioxygenase (IDO), and prostaglandin E2 were added to the co-culture system, and the percentages of Treg and Th17 cells were observed. Results: The percentage of peripheral Treg and Foxp3 MFI increased 1 week, 1 month, and 3 months after UC MSCs transplantation, while the Th17 proportion and MFI of IL-17 decreased 3 months, 6 months, and 12 months after the treatment, along with an increase in serum TGF-β at I week, 3 months, and 12 months and a decrease in serum TNF-a beginning at I week. There were no alterations in serums IL-6 and IL-17A before or after MSCT. In vitro studies showed that the UC MSCs dose-dependently up-regulated peripheral Treg proportion in SLE patients, which was no 展开更多
关键词 mesenchymal stem cells regulatory T cells systemic lupus erythematosus T helper 17 cells umbilical cord
原文传递
Human umbilical cord mesenchymal stem cells and the treatment of spinal cord injury 被引量:44
4
作者 CAO Fu-jiang FENG Shi-qing 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第2期225-231,共7页
Objective To review the recent studies about human umbilical cord mesenchymal stem cells (hUCMSCs) and advances in the treatment of spinal cord injury. Data sources Published articles (1983-2007) about hUCMSCs and... Objective To review the recent studies about human umbilical cord mesenchymal stem cells (hUCMSCs) and advances in the treatment of spinal cord injury. Data sources Published articles (1983-2007) about hUCMSCs and spinal cord injury were selected using Medline. Study selection Articles selected were relevant to development of mesenchymal stem cells (MSCs) for transplantation in spinal cord injury therapy. Of 258 originally identified articles 51 were selected that specifically addressed the stated purpose. Results Recent work has revealed that hUCMSCs share most of the characteristics with MSCs derived from bone marrow and are more appropriate to transplantation for cell based therapies. Conclusions Human umbilical cord could be regarded as a source of MSCs for experimental and clinical needs. In addition, as a peculiar source of stem cells, hUCMSCs may play an important role in the treatment of spinal cord injury. Chin Med J 2009;122(2):225-231 展开更多
关键词 umbilical cord mesenchymal stem cells spinal cord injuries
原文传递
WJSC 6^(th) Anniversary Special Issues(2):Mesenchymal stem cells Umbilical cord-derived mesenchymal stem cells:Their advantages and potential clinical utility 被引量:46
5
作者 Tokiko Nagamura-Inoue Haiping He 《World Journal of Stem Cells》 SCIE CAS 2014年第2期195-202,共8页
Human umbilical cord(UC)is a promising source of mesenchymal stem cells(MSCs).Apart from their prominent advantages,such as a painless collection procedure and faster self-renewal,UC-MSCs have shown the ability to dif... Human umbilical cord(UC)is a promising source of mesenchymal stem cells(MSCs).Apart from their prominent advantages,such as a painless collection procedure and faster self-renewal,UC-MSCs have shown the ability to differentiate into three germ layers,to accumulate in damaged tissue or inflamed regions,to promote tissue repair,and to modulate immune response.There are diverse protocols and culture methods for the isolation of MSCs from the various compartments of UC,such as Wharton’s jelly,vein,arteries,UC lining and subamnion and perivascular regions.In this review,we give a brief introduction to various compartments of UC as a source of MSCs and emphasize the potential clinical utility of UC-MSCs for regenerative medicine and immunotherapy. 展开更多
关键词 UMBILICAL cord MESENCHYMAL stem cells Wharton’s JELLY MULTIPOTENCY Immunotherapy
下载PDF
Mesenchymal stem cells derived from human placenta suppress allogeneic umbilical cord blood lymphocyte proliferation 被引量:36
6
作者 Chang Dong LI Wei Yuan ZHANG +4 位作者 He Lian LI Xiao Xia JIANG Yi ZHANG Pei Hsien TANG Ning MAO 《Cell Research》 SCIE CAS CSCD 2005年第7期539-547,共9页
Human placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesenchymal stem cell (MSC) maintenance medium. The homogenous layer of adherent cells exhibited a typical... Human placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesenchymal stem cell (MSC) maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblastlike morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitro differentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic and chondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73, CD105, CD166, laminin, fibronectin and vimentin while being negative for expression of CD31, CD34, CD45 and m-smooth muscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class Ⅰ major histocompatibility complex (MHC-I), but they did not express MHC-Ⅱ molecules. Additionally these cells could suppress umbilical cord blood (UCB) lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. This strongly implies that they may have potential application in allograft transplantation. Since placenta and UCB are homogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells (HSC) from UCB to reduce the potential graft-versus-host disease (GVHD) in recipients. 展开更多
关键词 mesenchymal stem cells human placenta umbilical cord blood immune regulation.
下载PDF
235/45R18轮胎带束层帘线的有限元优化设计 被引量:46
7
作者 黄兆阁 李长宇 +1 位作者 孟祥坤 雍占福 《橡胶工业》 CAS 2020年第3期209-213,共5页
通过四因子三水平正交试验,用有限元分析软件Abaqus对235/45R18轮胎带束层帘线截面积、帘线间距、1#带束层帘线角度、2#带束层帘线角度进行优化设计,分析带束层端部的最大Mises应力和最大应变能密度以及胎面最大接地应力。结果表明,带... 通过四因子三水平正交试验,用有限元分析软件Abaqus对235/45R18轮胎带束层帘线截面积、帘线间距、1#带束层帘线角度、2#带束层帘线角度进行优化设计,分析带束层端部的最大Mises应力和最大应变能密度以及胎面最大接地应力。结果表明,带束层帘线截面积为0.16 mm^2、帘线间距为1.6 mm、1#带束层帘线角度为58°、2#带束层帘线角度为122°时,轮胎带束层端部的最大Mises应力和最大应变能密度以及胎面最大接地应力最小,轮胎使用寿命更长。 展开更多
关键词 带束层 帘线 子午线轮胎 正交试验 优化设计 有限元分析 Mises应力 应变能密度 接地应力
下载PDF
Deferoxamine promotes recovery of traumatic spinal cord injury by inhibiting ferroptosis 被引量:43
8
作者 Xue Yao Yan Zhang +12 位作者 Jian Hao Hui-Quan Duan Chen-Xi Zhao Chao Sun Bo Li Bao-You Fan Xu Wang Wen-Xiang Li Xuan-Hao Fu Yong Hu Chang Liu Xiao-Hong Kong Shi-Qing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期532-541,共10页
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition repre... Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury. 展开更多
关键词 nerve REGENERATION iron spinal cord INJURY secondary INJURY ferroptosis DEFEROXAMINE GPX4 xCT treatment ASTROGLIOSIS lipid PEROXIDATION neural REGENERATION
下载PDF
Chronic complications of spinal cord injury 被引量:37
9
作者 Nebahat Sezer Selami Akkus Fatma Gülcin Ugurlu 《World Journal of Orthopedics》 2015年第1期24-33,共10页
Spinal cord injury(SCI) is a serious medical condition that causes functional, psychological and socioeconomic disorder. Therefore, patients with SCI experience significant impairments in various aspects of their life... Spinal cord injury(SCI) is a serious medical condition that causes functional, psychological and socioeconomic disorder. Therefore, patients with SCI experience significant impairments in various aspects of their life. The goals of rehabilitation and other treatment approaches in SCI are to improve functional level, decrease secondary morbidity and enhance health-relatedquality of life. Acute and long-term secondary medical complications are common in patients with SCI. However, chronic complications especially further negatively impact on patients' functional independence and quality of life. Therefore, prevention, early diagnosis and treatment of chronic secondary complications in patients with SCI is critical for limiting these complications, improving survival, community participation and health-related quality of life. The management of secondary chronic complications of SCI is also important for SCI specialists, families and caregivers as well as patients. In this paper, we review data about common secondary longterm complications after SCI, including respiratory complications, cardiovascular complications, urinary and bowel complications, spasticity, pain syndromes, pressure ulcers, osteoporosis and bone fractures. The purpose of this review is to provide an overview of risk factors, signs, symptoms, prevention and treatment approaches for secondary long-term complications in patients with SCI. 展开更多
关键词 Spinal cord injury Chronic complications Management of complications Long-term morbidity Secondary morbidity of spinal cord injury
下载PDF
WJSC 6^(th) Anniversary Special Issues(2):Mesenchymal stem cells Mesenchymal stem cells in the treatment of spinal cord injuries:A review 被引量:35
10
作者 Venkata Ramesh Dasari Krishna Kumar Veeravalli Dzung H Dinh 《World Journal of Stem Cells》 SCIE CAS 2014年第2期120-133,共14页
With technological advances in basic research,the intricate mechanism of secondary delayed spinal cord injury(SCI)continues to unravel at a rapid pace.However,despite our deeper understanding of the molecular changes ... With technological advances in basic research,the intricate mechanism of secondary delayed spinal cord injury(SCI)continues to unravel at a rapid pace.However,despite our deeper understanding of the molecular changes occurring after initial insult to the spinal cord,the cure for paralysis remains elusive.Current treatment of SCI is limited to early administration of high dose steroids to mitigate the harmful effect of cord edema that occurs after SCI and to reduce the cascade of secondary delayed SCI.R ecent evident-based clinical studies have cast doubt on the clinical benefit of steroids in SCI and intense focus on stem cell-based therapy has yielded some encouraging results.An array of mesenchymal stem cells(MSCs)from various sources with novel and promising strategies are being developed to improve function after SCI.In this review,we briefly discuss the pathophysiology of spinal cord injuries and characteristics and the potential sources of MSCs that can be used in the treatment of SCI.We will discuss the progress of MSCs application in research,focusing on the neuroprotective properties of MSCs.Finally,we will discuss the results from preclinical and clinical trials involving stem cell-based therapy in SCI. 展开更多
关键词 Spinal cord injury MESENCHYMAL STEM CELLS Bone marrow STROMAL CELLS Umbilical cord DERIVED MESENCHYMAL STEM CELLS Adipose tissue DERIVED MESENCHYMAL STEM CELLS
下载PDF
Functional recovery after rhesus monkey spinal cord injury by transplantation of bone marrow mesenchymal-stem cell-derived neurons 被引量:34
11
作者 DENG Yu-bin YUAN Qing-tao +4 位作者 LIU Xiao-gang LIU Xiao-lin LIU Yu LIU Zu-guo ZHANG Cheng 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第18期1533-1541,共9页
Background The treatment of spinal cord injury is still a challenge. This study aimed at evaluating the therapeutical effectiveness of neurons derived form mesenchymal stem cells (MSCs) for spinal cord injury. Metho... Background The treatment of spinal cord injury is still a challenge. This study aimed at evaluating the therapeutical effectiveness of neurons derived form mesenchymal stem cells (MSCs) for spinal cord injury. Methods In this study, rhesus MSCs were isolated and induced by cryptotanshinone in vitro and then a process of RT-PCR was used to detect the expression of glutamic acid decarboxylase (GAD) gene. The induced MSCs were tagged with Hoechst 33342 and injected into the injury site of rhesus spinal cord made by the modified Allen method. Following that, behavior analysis was made after 1 week, 1 month, 2 months and 3 months. After 3 months, true blue chloride retrograde tracing study was also used to evaluate the reestablishment of axons pathway and the hematoxylin-eosin (HE) staining and immunohistochemistry were performed after the animals had been killed. Results In this study, the expression of mRNA of GAD gene could be found in the induced MSCs but not in primitive MSCs and immunohistochemistry could also confirm that rhesus MSCs could be induced and differentiated into neurons. Behavior analysis showed that the experimental animals restored the function of spinal cord up to grade 2 -3 of Tarlov classification. Retrograde tracing study showed that true blue chollide could be found in the rostral thoracic spinal cords, red nucleus and sensory-motor cortex. Conclusions These results suggest that the transplantation is safe and effective. 展开更多
关键词 mesenchymal stem cell·neuron·spinal cord injury·cell transplantation·rhesus
原文传递
Multimodal treatment for spinal cord injury: a sword of neuroregeneration upon neuromodulation 被引量:36
12
作者 Ya Zheng Ye-Ran Mao +2 位作者 Ti-Fei Yuan Dong-Sheng Xu Li-Ming Cheng 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1437-1450,共14页
Spinal cord injury is linked to the interruption of neural pathways,which results in irreversible neural dysfunction.Neural repair and neuroregeneration are critical goals and issues for rehabilitation in spinal cord ... Spinal cord injury is linked to the interruption of neural pathways,which results in irreversible neural dysfunction.Neural repair and neuroregeneration are critical goals and issues for rehabilitation in spinal cord injury,which require neural stem cell repair and multimodal neuromodulation techniques involving personalized rehabilitation strategies.Besides the involvement of endogenous stem cells in neurogenesis and neural repair,exogenous neural stem cell transplantation is an emerging effective method for repairing and replacing damaged tissues in central nervous system diseases.However,to ensure that endogenous or exogenous neural stem cells truly participate in neural repair following spinal cord injury,appropriate interventional measures(e.g.,neuromodulation)should be adopted.Neuromodulation techniques,such as noninvasive magnetic stimulation and electrical stimulation,have been safely applied in many neuropsychiatric diseases.There is increasing evidence to suggest that neuromagnetic/electrical modulation promotes neuroregeneration and neural repair by affecting signaling in the nervous system;namely,by exciting,inhibiting,or regulating neuronal and neural network activities to improve motor function and motor learning following spinal cord injury.Several studies have indicated that fine motor skill rehabilitation training makes use of residual nerve fibers for collateral growth,encourages the formation of new synaptic connections to promote neural plasticity,and improves motor function recovery in patients with spinal cord injury.With the development of biomaterial technology and biomechanical engineering,several emerging treatments have been developed,such as robots,brain-computer interfaces,and nanomaterials.These treatments have the potential to help millions of patients suffering from motor dysfunction caused by spinal cord injury.However,large-scale clinical trials need to be conducted to validate their efficacy.This review evaluated the efficacy of neural stem cells and magnetic or electrical stimu 展开更多
关键词 brain-computer interface technology multimodal rehabilitation nerve regeneration neural circuit reconstruction neural regeneration NEUROMODULATION rehabilitation training spinal cord injury stem cells transcranial direct current stimulation transcranial magnetic stimulation
下载PDF
Function of microglia and macrophages in secondary damage after spinal cord injury 被引量:34
13
作者 Xiang Zhou Xijing He Yi Ren 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第20期1787-1795,共9页
Spinal cord injury (SCI) is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary... Spinal cord injury (SCI) is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary injury mechanisms, the inflammatory response is the major contrib- utor and results in expansion of the lesion and further loss of neurologic function. Meanwhile, the inflammation directly and indirectly dominates the outcomes of SCI, including not only pain and motor dysfunction, but also preventingneuronal regeneration. Microglia and macrophages play very important roles in secondary injury. Microglia reside in spinal parenchyma and survey the microenvironment through the signals of injury or infection. Macrophages are derived from monocytes recruited to injured sites from the peripheral circulation. Activated resident microglia and monocyte-derived macrophages induce and magnify immune and inflammatory responses not only by means of their secretory moleculesand phagocytosis, but also through their influence on astrocytes, oligodendrocytes and demyelination. In this review, we focus on the roles of mi- croglia and macrophages in secondary injury and how they contribute to the sequelae of SCI. 展开更多
关键词 astrocytes cytokines CHEMOKINES DEMYELINATION inflammation OLIGODENDROCYTES MI/M2 activation MACROPHAGES MICROGLIA secondary damage spinal cord injury
下载PDF
Electroacupuncture in the repair of spinal cord injury:inhibiting the Notch signaling pathway and promoting neural stem cell proliferation 被引量:33
14
作者 Xin Geng Tao Sun +3 位作者 Jing-hui Li Ning Zhao Yong Wang Hua-lin Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第3期394-403,共10页
Electroacupuncture for the treatment of spinal cord iniury has a good dinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Daw- ley rats was clamped fo... Electroacupuncture for the treatment of spinal cord iniury has a good dinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Daw- ley rats was clamped for 60 seconds. Dazhui (GV14) and Mingmen (GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expres- sion of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem ceils. 展开更多
关键词 nerve regeneration spinal cord electroacupuncture therapy neural stem cells notchsignaling pathway ASTROCYTES inflammation survival curve PROLIFERATION differentiation real-timequantitative PCR western blot assay neural regeneration
下载PDF
Extracellular matrix gel is necessary for in vitro cultivation of insulin producing cells from human umbilical cord blood derived mesenchymal stem cells 被引量:31
15
作者 GAO Feng WU De-quan HU Yan-hua JIN Guang-xin 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第9期811-818,共8页
Background Pancreatic islet cell transplantation is an effective approach to treat type 1 diabetes. However, this therapy is not widely used because of the severe shortage of transplantable donor islets. This study in... Background Pancreatic islet cell transplantation is an effective approach to treat type 1 diabetes. However, this therapy is not widely used because of the severe shortage of transplantable donor islets. This study investigated whether mesenchymal stem cells (MSCs) derived from human umbilical cord blood (UCB) could be transdifferentiated into insulin producing cells in vitro and the role of extracellular matrix (ECM) gel in this procedure. Methods Human UCB samples were collected and MSCs were isolated. MSCs specific marker proteins were analyzed by a flow cytometer, The capacities of osteoblast and adipocyte to differentiate were tested. Differentiation into islet like cell was induced by a 15-day protocol with or without ECM gel. Pancreatic characteristics were evaluated with immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR) and flow cytometry. Insulin content and release in response to glucose stimulation were detected with chemiluminescent immunoassay system. Results Sixteen MSCs were isolated from 42 term human UCB units (38%). Human UCB-MSCs expressed MSCs specific markers and could be induced in vitro into osteoblast and adipocyte. Islet like cell clusters appeared about 9 days after pancreatic differentiation in the inducing system with ECM gel. The insulin positive cells accounted for (25.2~3.4)% of the induced cells. The induced cells expressed islet related genes and hormones, but were not very responsive to glucose challenge. When MSCs were induced without ECM gel, clusters formation and secretion of functional islet proteins could not be observed, Conclusions Human UCB-MSCs can differentiate into islet like cells in vitro and ECM gel plays an important role in pancreatic endocrine cell maturation and formation of three dimensional structures. 展开更多
关键词 umbilical cord blood mesenchymal stem cells induction insulin producing cells extracellular matrix
原文传递
Human neural stem cells promote corticospinal axons regeneration and synapse reformation in injured spinal cord of rats 被引量:30
16
作者 LIANG Peng JIN Lian-hong +2 位作者 LIANG Tao LIU En-zhong Shi-guang 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第16期1331-1338,共8页
Background Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem ce... Background Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem cell (NSC) in promoting corticospinal axons regeneration and synapse reformation in rats with injured spinal cord. Methods NSCs were isolated from the cortical tissue of spontaneous aborted human fetuses in accordance with the ethical request. The cells were discarded from the NSC culture to acquire NSC-conditioned medium. Sixty adult Wistar rats were randomly divided into four groups (n=15 in each): NSC graft, NSC medium, graft control and medium control groups. Microsurgical transection of the spinal cord was performed in all the rats at the T11. The NSC graft group received stereotaxic injections of NSCs suspension into both the spinal cord stumps immediately after transection; graft control group received DMEM injection. In NSC medium group, NSC-conditioned medium was administered into the spinal cord every week; NSC culture medium was administered to the medium control group. Hindlimb motor function was assessed using the BBB Locomotor Rating Scale. Regeneration of biotin dextran amine (BDA) labeled corticospinal tract was assessed. Differentiation of NSCs and the expression of synaptophysin at the distal end of the injured spinal cord were observed under a confocal microscope. Group comparisons of behavioral data were analyzed with ANOVA. Results NSCs transplantation resulted in extensive growth of corticospinal axons and locomotor recovery in adult rats after complete spinal cord transection, the mean BBB scores reached 12.5 in NSC graft group and 2.5 in graft control group (P〈 0.05). There was also significant difference in BBB score between the NSC medium (11.7) and medium control groups (3.7, P〈 0.05). BDA traces regenerated fibers sprouted across the lesion site and entered the caudal part of the spinal cord. Synaptophysin expression colocalized with BDA positiv 展开更多
关键词 spinal cord injuries stem cells nerve regeneration
原文传递
The glial scar in spinal cord injury and repair 被引量:29
17
作者 Yi-Min Yuan Cheng He 《Neuroscience Bulletin》 SCIE CAS CSCD 2013年第4期421-435,共15页
Glial scarring following severe tissue damage and inflammation after spinal cord injury (SCI) is due to an extreme, uncontrolled form of reactive astrogliosis that typically occurs around the injury site. The scarri... Glial scarring following severe tissue damage and inflammation after spinal cord injury (SCI) is due to an extreme, uncontrolled form of reactive astrogliosis that typically occurs around the injury site. The scarring process includes the misalignment of activated astrocytes and the deposition of inhibitory chondroitin sulfate proteoglycans. Here, we first discuss recent developments in the molecular and cellular features of glial scar formation, with special focus on the potential cellular origin of scar-forming cells and the molecular mechanisms underlying glial scar formation after SCI. Second, we discuss the role of glial scar formation in the regulation of axonal regeneration and the cascades of neuro-inflammation. Last, we summarize the physical and pharmacological approaches targeting the modulation of glial scarring to better understand the role of glial scar formation in the repair of SCI. 展开更多
关键词 glial scar spinal cord injury axonal regeneration astrocyte activation reactive astrogliosis neuro-inflammation
原文传递
Early neurosurgical intervention of spinal cord contusion: an analysis of 30 cases 被引量:29
18
作者 ZHU Hui FENG Ya-ping +4 位作者 Young Wise YOU Si-wei SHEN Xue-feng LIU Yan-sheng JU Gong 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第24期2473-2478,共6页
Background The incidence of spinal injury with spinal cord contusion is high in developed countries and is now growing in China. Furthermore, spinal cord injury happens mostly in young people who have a long life expe... Background The incidence of spinal injury with spinal cord contusion is high in developed countries and is now growing in China. Furthermore, spinal cord injury happens mostly in young people who have a long life expectance. A large number of patients thus are wheelchair bound for the rest of their lives. Therefore, spinal cord injury has aroused great concern worldwide. Despite great efforts, recovery from spinal cord injury remains unsatisfactory. Based on the pathology of spinal cord contusion, an idea of early neurosurgical intervention has been formulated in this study. Methods A total of 30 patients with "complete" spinal cord injury or classified as American Spinal Injury Association (ASIA)-A were studied. Orthopedic treatment of the injured vertebra(e), internal fixation of the vertebral column, and bilateral laminectomy for epidural decompression were followed directly by neurosurgical management, including separation of the arachnoid adhesion to restore cerebrospinal fluid flow and debridement of the spinal cord necrotic tissue with concomitant intramedullary decompression. Rehabilitation started 17 days after the operation. The final outcome was evaluated after 3 months of rehabilitation. Pearson chi-square analysis was used for statistical analysis. Results All the patients recovered some ability to walk. The least recovered patients were able to walk with a wheeled weight support and help in stabilizing the weight bearing knee joint (12 cases, 40%). Thirteen patients (43%) were able to walk with a pair of crutches, a stick or without any support. The timing of the operation after injury was important. An optimal operation time window was identified at 4-14 days after injury. Conclusions Early neurosurgical intervention of spinal cord contusion followed by rehabilitation can significantly improve the locomotion of the patients. It is a new idea of a therapeutic approach for spinal cord contusion and has been proven to be very successful. 展开更多
关键词 spinal cord CONTUSION NEUROSURGERY REHABILITATION
原文传递
Effect of nerve growth factor on neuronal apoptosis after spinal cord injury in rats 被引量:21
19
作者 曹晓建 汤长华 罗永湘 《Chinese Journal of Traumatology》 CAS 2002年第3期131-135,共5页
Objective: To explore the molecular mechanism of the protective effect of nerve growth factor (NGF) on injured spinal cord. Methods: The posterior T 8 (the 8th thoracic segment) spinal cords of 60 Wistar rats were inj... Objective: To explore the molecular mechanism of the protective effect of nerve growth factor (NGF) on injured spinal cord. Methods: The posterior T 8 (the 8th thoracic segment) spinal cords of 60 Wistar rats were injured by impacts caused by objects (weighing 10 g) falling from a height of 2.5 cm with Allens way. Solution with nerve growth factors (NGF) was given to 30 rats (the NGF group) through a microtubule inserted into the subarachnoid cavity immediately, and at 2, 4, 8, 12 and 24 hours after spinal cord injury (SCI) respectively. Normal saline (NS) with same volume was given to the other 30 rats (the NS group) with the same method. And 5 normal rats were taken as the normal controls. The expression of bcl 2 and bax proteins in spinal cord was detected with immunohistochemistry. The apoptotic neurons in spinal cord were measured with terminal deoxynucleotidyl transferase mediated dUTP biotin nick end labeling of DNA fragments (TUNEL) staining. Results: The positive expression of bcl 2 protein was strong in the normal controls, but decreased in the NS group, and increased significantly in the NGF group as compared with that of the NS group (P< 0.01 ). The positive expression of bax protein was also strong in the normal controls, but increased in the NS group, and decreased significantly in the NGF group as compared with that of the NS group (P< 0.01 ). Apoptotic neurons were found in the NS group, and they decreased significantly in the NGF group as compared with that of the NS group (P< 0.01 ).Conclusions: NGF can protect the injured nerve tissues through stimulating the expression of bcl 2 protein, inhibiting the expression of bax protein and inhibiting the neuronal apoptosis after SCI. 展开更多
关键词 Nerve growth factors APOPTOSIS Spinal cord Wounds and injuries
原文传递
Prenatal cytogenetic diagnosis study of 2782 cases of high-risk pregnant women 被引量:27
20
作者 ZHANG Lin ZHANG Xiao-hong LIANG Mei-ying REN Mei-hong 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第4期423-430,共8页
Background Prenatal diagnoses are extremely advantageous for pregnant women with high-risk indicators and can help prevent the birth of malformed infants. However, no large-scale statistical study analyzing the correl... Background Prenatal diagnoses are extremely advantageous for pregnant women with high-risk indicators and can help prevent the birth of malformed infants. However, no large-scale statistical study analyzing the correlation between fetal chromosome disorders and abnormal indicators during pregnancy has been done in China. The objectives of this study were to diagnose and analyze fetal chromosome abnormalities, determine the feasibility of the various prenatal test methods and establish diagnostic guidelines for the early, middle, and late trimesters. Methods From January 2004 to May 2009, 2782 pregnant women at high-risk underwent prenatal diagnoses. Categorized data expressed as either actual counts or percentages were analyzed by the chi-square or Fisher's exact test. Chorionic villus sampling was performed in the early-trimester (10-12 weeks of gestation), amniocentesis in mid-trimester (16-28 weeks of gestation), and umbilical cord blood collection in mid- or late-trimester (16-37 weeks of gestation). In 51 cases either autopsy samples from intrauterine fetal deaths or placental tissues from aborted fetuses were tested. Results Chromosomal abnormalities were observed in 3.99% (111/2782) of the samples. Overall, the success rate of cytogenetic analysis for high-risk pregnancy groups was 98.17% (2731/2782). It was significantly less successful when used to analyze data from the chorionic villus sampling compared with that from amniocentesis and umbilical cord blood (P=-0.000). Abnormal chromosome carriers had the highest percentage of abnormal chromosomes (67.86%) when compared with chromosomal abnormalities in patients with ultra-sonographic "soft markers" (11.81%), advanced maternal age (4.51%) and those who had positive serum screening results (P=-0.000). Conclusions Invasive prenatal diagnostic techniques are feasible tools for confirming fetal chromosomal abnormalities. Abnormal chromosomes detected in one of the parents carrying abnormal chromosome, ultrasound 展开更多
关键词 chorionic villus sampling AMNIOCENTESIS umbilical cord blood collection chromosomal karyotype prenatal diagnosis
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部