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91.
Peng Shi Ana Chee Weijun Liu Po-Hsin Chou Jun Zhu Howard S. An 《The spine journal》2019,19(1):171-181
BACKGROUND CONTEXT
Increasing evidence suggests transplanting viable cells into the degenerating intervertebral disc (IVD) may be effective in treating disc degeneration and back pain. Clinical studies utilizing autologous or allogeneic mesenchymal stem cells to treat patients with back pain have reported some encouraging results. Animal studies have shown that cells injected into the disc can survive for months and have regenerative effects. Studies to determine the advantages and disadvantages of cell types and sources for therapy are needed.PURPOSE
The objective of this study is to determine the impact of donor source on the therapeutic effects of dermal fibroblast treatment on disc degeneration and inflammation.STUDY DESIGN
Using the rabbit disc degeneration model, we compared transplantation of neonatal human dermal fibroblasts (nHDFs) and rabbit dermal fibroblasts (RDFs) into rabbit degenerated discs on host immune response, disc height, and IVD composition.METHODS
New Zealand white rabbits received an annular puncture using an 18-guage needle to induce disc degeneration. Four weeks after injury, rabbit IVDs were treated with 5?×?106 nHDFs, RDFs, or saline. At eight weeks post-treatment, animals were sacrificed. X-ray images were obtained. IVDs were isolated for inflammatory and collagen gene expression analysis using real-time polymerase chain reaction and biochemical analysis of proteoglycan contents using dimethylmethylene blue assay. These studies were funded by a research grant from SpinalCyte, LLC ($414,431).RESULTS
Eight weeks after treatment, disc height indexes of discs treated with nHDF increased significantly by 7.8% (p<.01), whereas those treated with saline or RDF increased by 1.5% and 2.0%, respectively. Gene expression analysis showed that discs transplanted with nHDFs and RDFs displayed similar inflammatory responses (p=.2 to .8). Compared to intact discs, expression of both collagen types I and II increased significantly in nHDF-treated discs (p<.05), trending to significant in RDF-treated discs, and not significantly in saline treated discs. The ratio of collagen type II/collagen type I was higher in the IVDs treated with nHDFs (1.26) than those treated with RDFs (0.81) or saline (0.59) and intact discs (1.00). Last, proteoglycan contents increased significantly in discs treated with nHDF (p<.05) and were trending toward significance in the RDF-treated discs compared to those treated with saline.CONCLUSIONS
This study showed that cell transplantation with nHDF into degenerated IVDs can significantly increase markers of disc regeneration (disc height, collagen type I and II gene expression, and proteoglycan contents). Transplantation with RDFs showed similar regenerative trends, but these trends were not significant. This study also showed that the human cells transplanted into the rabbit discs did not induce a higher immune response than the rabbit cells. These results support that the IVD is immune privileged and would tolerate allogeneic or xenogeneic grafts. 相似文献92.
目的分析结合应用腔内凸阵探头(ICAP)诊断锁骨下动脉起始部溃疡型斑块的检出率及准确率。
方法选取江汉大学附属湖北省第三人民医院超声影像科自2018年5月至2019年12月接受诊疗的后循环缺血伴反复脑卒中患者248例,分别单独使用高频线阵探头(HFLP)及结合应用ICAP对双侧锁骨下动脉行彩色多普勒超声检查,分类记录锁骨下动脉斑块个数、形态、回声等情况,以高分辨率CT血管造影(HD-CTA)技术的诊断结果为参照,比较单独使用HFLP和结合应用ICAP的斑块检出情况。
结果以HD-CTA的诊断结果为标准,相比单独应用HFLP,结合应用ICAP对于锁骨下动脉起始部粥样斑块的检出率增加不明显,差异无统计学意义(P>0.05),粥样硬化斑块的形态、回声描述的准确率、溃疡型粥样硬化斑块的检出率增加明显,差异均有统计学意义(P<0.05)。
结论结合应用ICAP对于诊断锁骨下动脉起始段溃疡型粥样硬化斑具有较高的临床应用价值。 相似文献
93.
Weijun Liu David Liu Justin Zheng Peng Shi Po-Hsin Chou Chundo Oh Di Chen Howard S. An Ana Chee 《The spine journal》2017,17(5):720-726
Background Context
Disc degeneration is associated with the progressive loss of the proteoglycan content of the intervertebral disc, decreased matrix synthesis, higher concentrations of proteolytic enzymes, and increased levels of proinflammatory cytokines. In previous studies, we have shown that C-C chemokine ligand (CCL)2, CCL3, and CCL5 are highly expressed by cultured nucleus pulposus (NP) and annulus fibrosus (AF) cells that have been treated by interleukin-1. The major function of these chemokines is to recruit immune cells into the disc. It is unclear if disc cells can respond to these chemokines. Recent studies by Phillips et al. (2015) showed that NP cells express a number of cytokines and chemokine receptors.Purpose
The purpose of this study is to determine the gene and protein expression of C-C chemokine receptor (CCR)1, CCR2, and CCR5 in NP and AF cells, and to test if these receptors can respond to their ligands in these cells by cell signaling and migration.Study Design/Setting
This is an in vitro study.Methods
For RNA, surface expression, and cell signaling studies, human cells were isolated from the NP and AF tissues collected after spine surgery or from donated spine segments (Gift of Hope Human Donor & Tissue Network of Illinois) and cultured in monolayer. The gene expression of human CCR1, CCR2, and CCR5 was analyzed using real-time polymerase chain reaction. The surface expression of CCR1, CCR2, and CCR5 was analyzed using flow cytometry and fluorescently tagged antibodies specific for these proteins. Extracellular signal-regulated kinase (ERK) phosphorylation was analyzed from the cell lysates of NP and AF cells treated with CCL2 and CCL5 for 1 hour using enzyme-linked immunosorbent assay. Migration of primary rabbit AF cells was assayed using 8-µm Corning Transwell inserts in the presence or absence of CCL5. This study was partially funded by a North American Spine Society 2014 Basic Research Grant Award ($50,000).Results
RNA analysis showed that gene expression of CCR1, CCR2, and CCR5 was evident in human NP and AF cells (n=6). Only a small population of NP and AF cells expressed CCR1 (1.9% and 1.2%, respectively) and CCR2 (0.8% and 1.4%, respectively) on the cell surface, whereas a larger percentage expressed CCR5 (12.7% and 11.6%, respectively). Significantly higher levels of ERK phosphorylation were detected in AF cells after treatment with CCL5 and not CCL2. Treatment with either chemokine did not cause significantly higher ERK phosphorylation in NP cells. There was an increase in average AF cell migration in the presence of CCL5. The increase was significant when the migration was induced with CCL5 (500?ng/mL) at both 2- and 6-hour time points.Conclusions
CCR5 is expressed at the RNA level and on the cell surface of NP and AF cells. In the presence of CCL5, we detected increased levels of ERK phosphorylation and AF cell migration, suggesting that the CCR5 receptors in AF cells are functional. These data suggest that AF cells may have the ability to migrate in response to disc damage or inflammation. 相似文献94.
在分析梳理面向共享的医学影像结果报告业务流程的基础上,借鉴HL7 CDA R2架构,基于我国卫生信息共享文档编制规范,构建了医学影像结果报告的结构化模板,并与卫生信息数据元目录进行了映射。其中文档头包括主题数据和管理数据,文档体分为临床信息、成像设备信息及过程描述、检查结果信息3个章节及若干条目。 相似文献
95.
96.
二维超声及彩超诊断未破型宫外孕 总被引:13,自引:1,他引:12
目的 探讨未破型宫外孕的超声诊断方法。方法 选择16 例经二维超声与彩色多普勒血流显像首诊,临床确诊的未破型宫外孕病例,对其超声检查资料进行分析。结果 全部病例均显示附件包块。12 例(75 % ) 显示肿块内相对周围组织增多的彩色血流信号。频谱多普勒表现附件肿块内低阻血流频谱。RI值042 ±0.08,子宫动脉及卵巢血流无特征性变化。结论 附件区肿块,肿块内相对周围组织增多的彩色血流信号是超声诊断未破型宫外孕的关键。输卵管妊娠的病理生理改变与超声图像表现相关。疑为宫外孕时,耐心细致地寻找附件包块至关重要。 相似文献
97.
98.
99.
目的:探究多模式CT检查评价缺血性脑卒中患者缺血半暗带、侧支循环与预后的关系。方法:选择2018年12月至2020年12月来江汉大学附属湖北省第三人民医院就诊的缺血性脑卒中患者120例,男68例、女52例,年龄(62.96±4.23)岁。对患者进行多模式CT检查,处理数据得到相对脑血容量(rCBV)、相对脑血流量(rC... 相似文献
100.
目的 探讨微小RNA(miR)144-3p促进心肌细胞肥厚及心功能损伤的作用及可能的机制。 方法 将45只C57BL/6小鼠随机分为对照组、心肌肥厚模型组及miR144-3p转染组,采用超声心动图检测3组小鼠心功能相关指标;实验结束后,处死小鼠,对心肌组织进行HE染色;采用Real-time PCR技术,检测各组小鼠心肌细胞中miR144-3p的表达差异;采用Western blotting检测心肌组织中脑钠肽(BNP)蛋白、抗核因子(ANF)蛋白、β-肌球蛋白重链(β-MHC)、肌动蛋白α1(Acta1)蛋白、组蛋白去乙酰化酶2(HDAC2)蛋白的表达水平。 结果 与对照组相比,模型组和转染组的左室射血分数(EF)、舒张期室间隔厚度(IVSd)、收缩期室间隔厚度(IVSs)、舒张期左室后壁厚度(IVPWd)、收缩期左室后壁厚度(IVPWs)、心重指数、左心指数明显较高,而收缩期左室内径(LVDs)、舒张期左室内径(LVDd)较低(P<0.05),但模型组、转染组之间各项指标差异不明显(P>0.05)。与对照组相比,模型组和转染组miR144-3p相对表达量明显升高,且转染组明显高于模型组(P<0.05)。与对照组相比,模型组和转染组ANF、β-MHC、Acta1和HDAC2蛋白表达水平明显增高(P<0.05)。 结论 MiR144-3p可能通过上调HDAC2加重心肌肥厚及心功能损伤。 相似文献