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91.
慢性心功能不全时经主动脉移植干细胞的可行性研究   总被引:6,自引:2,他引:6  
心肌梗死或/和慢性心功能不全时,心脏干细胞移植是一项颇有应用前景的新的治疗技术。但是,对于非缺血性心脏病所致的慢性心功能不全,目前所采用的移植路径有一定的局限性。本试验拟研究慢性心功能不全时,封堵主动脉窦上部经主动脉根部移植干细胞是否可行。阿霉素所致的慢性心功能不全兔模型,采用双球囊封堵主动脉窦上部经主动脉根部自体移植骨髓单核细胞,4周后评价心功能。在封堵主动脉窦上部经主动脉根部移植干细胞时,无1例因移植手术死亡。双球囊充盈时造影显示,主动脉窦显影良好,大部分情况下,左、右冠状动脉可显影。骨髓单核细胞移植4周后,左室射血分数改善明显(P=0 .0 34)。所以,慢性心功能不全时,封堵主动脉窦上部经主动脉根部移植干细胞安全可行。  相似文献   
92.
The cytotoxicity of trivalent and pentavalent inorganic arsenic salts was determined in mouse fibroblasts in vitro. Concentrations of As (III) in the M range led to a reduction of proliferation and viability with a concomitant increase in LDH release and stimulation of lactic acid production. Similar effects were noted with approximately 10-fold greater molar concentrations of As(V). Cells pretreated with a low As(III) concentration are less sensitive to toxic doses of As(III) or As(V).Uptake of As(III) by the fibroblasts is greater than that of As(V). Both forms of inorganic arsenic are converted intracellularly to monomethylarsonic (MMA) and dimethylarsinic (DMA) acids, which are then released into the culture medium. In As-pretreated cells, which are more resistant to As toxicity, biotransformation of inorganic arsenic to MMA and DMA is increased.  相似文献   
93.
感染因素或宫腔手术操作导致的子宫内膜损伤阻碍胚胎的着床和发育,严重影响妇女的身心健康与生育能力。但目前治疗手段有限且效果欠佳。干细胞具有自我更新和分化潜能,在病变损伤组织的修复过程中发挥重要作用。骨髓间充质干细胞、脐带间充质干细胞、子宫内膜干细胞、脂肪干细胞和人羊膜上皮细胞等多种干细胞治疗子宫内膜损伤已在动物模型和临床研究中开展,并展现出巨大的潜力。干细胞治疗可促进子宫内膜细胞再生,改善子宫内膜厚度和微血管密度,提高受孕率并改善生育结局。干细胞治疗从形态和功能上改善子宫内膜,促进月经和生殖功能的恢复,为治疗子宫内膜损伤提供一种新策略。  相似文献   
94.
Poor tendon to bone healing following rotator cuff repair has led to the continued interest and investigation into biological augmentation. The biology of tendinopathy is not fully understood and consequently the availability of disease modifying therapeutic targets is limited. A ceiling of benefit has been reached by mechanical optimisation of rotator cuff repair and thus, in order to improve healing rates, a biological solution is required. This review focuses on the strategies to biologically augment rotator cuff disorders with an emphasis on rotator cuff repair. Leucocyte rich platelet rich plasma has been shown to improve healing rates without clinically relevant improvements in outcome scores. Similarly, improved healing rates have also been reported with bone marrow stimulation and in long-term follow-up with bone marrow concentrate. Extracellular matrix (ECM) and synthetic scaffolds can increase healing through mechanical and or biological augmentation. A potential third category of scaffold is bio-inductive and has no mechanical support. Studies involving various scaffolds have shown promising results for augmentation of large to massive tears and is likely to be most beneficial when tendon quality is poor, however level I evidence is limited.  相似文献   
95.
目的检测运用羟基磷灰石及β-磷酸三钙制备的双相钙磷陶瓷的生物相容性及其异位骨诱导效率。方法采用化学共沉淀法及过氧化氢发泡法,将羟基磷灰石及β-磷酸三钙以6∶4的比例在1 100 ℃条件下烧结3 h获得双相钙磷陶瓷,利用X线衍射评估材料组成成分。分离SD大鼠骨髓间充质干细胞,接种于双相钙磷陶瓷,通过扫描电镜、鬼笔环肽及DAPI染色观察细胞的黏附,CCK8法评估细胞增殖,碱性磷酸酶测定法评估骨髓间充质干细胞的碱性磷酸酶表达活性。将不含骨髓间充质干细胞的双相钙磷陶瓷置入比格犬竖脊肌内,于4、8、12周对样本行大体检测、组织染色,测算新骨生成率,从而评估双相钙磷陶瓷的异位骨诱导效率。结果成功制备双相钙磷陶瓷,X线衍射分析可见羟基磷灰石及β-磷酸三钙特异性的衍射峰。扫描电镜可见双相钙磷陶瓷表面广泛分布大孔及连通孔,孔壁粗糙不平,孔内可见均匀分布的微孔。鬼笔环肽及DAPI染色显示,骨髓充质干细胞在材料表面伸展黏附,共培养后逐渐从不规则形转变为均一的长梭形。CCK8法提示共培养后第1天,细胞活力降低,而第3、4、5、7天,细胞增殖活力逐渐增加。碱性磷酸酶活性检测提示,与对照组相比,共培养后第1、7天,双相钙磷陶瓷组的骨髓间充质干细胞可分泌更多的碱性磷酸酶。双相钙磷陶瓷顺利置入比格犬竖脊肌内,术后8周材料孔隙内可见骨样组织沉积,术后12周大孔成骨比例为0.77±0.11,孔内成骨面积比例为0.71±0.14。结论双相钙磷陶瓷具有良好的生物相容性及异位骨诱导效率。  相似文献   
96.
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
97.
Bone marrow stromal cells (BMSCs) have been isolated for the first time by Friedenstein et al. and since then have been considered the progenitor cells for the skeletal tissues. Indeed BMSCs are clonogenic, fibroblastic in shape, and can differentiate along multiple lineages such as osteoblasts, chondrocytes, adipocytes, and hematopoiesis-supportive stroma. When implanted in vivo on a three-dimensional bioceramic scaffold into immunocompromised mice, BMSCs form bone and hematopoiesis-supportive stroma. The ease of harvest from a donor bone marrow together with the ability to form bone in vivo make BMSCs ideal for clinical applications. Thus, ex vivo expanded BMSCs have been employed, first in large animal models, then in human clinical trials, to repair large bone segmental defects. Further investigation of the expanded BMSC population led to the observation that in vitro expansion appears a limiting passage: cells tend to senesce and lose their multidifferentiation potential with time in culture. To overcome these limitations, two approaches have been proposed: (1) identification of the appropriate culture conditions to prevent senescence by possibly selecting a subpopulation with stem cell characteristics, and (2) engineering of the cells by transfection with the telomerase gene to prevent cells from telomere shortening and consequent aging.  相似文献   
98.
目的:检测肿瘤细胞Nucleostemin(NS)的表达,研究NS特异性RNA干扰对HeLa细胞体内外增殖的影响。方法:提取6种肿瘤细胞总RNA,用 RT-PCR和Northern blot方法检测NS的表达。用NS特异性siRNA表达载体转染HeLa细胞,观察转染的HeLa细胞(简称NS-siRNA-HeLa细胞)体内外增殖的变化。结果:6种肿瘤细胞中NS明显高表达。体外培养的NS-siRNA-HeLa细胞中NS表达显著低于对照组,G0/G1期细胞百分率显著升高。体内致瘤实验显示,NS-siRNA-HeLa细胞在裸鼠体内增殖显著低于对照组。结论: NS在肿瘤细胞中高表达具有普遍性。NS特异性RNA干扰使HeLa细胞进入S期受阻,并可明显降低HeLa细胞体内外的增殖能力。  相似文献   
99.
为了探讨缺氧,缺血及再灌注损伤的发生的机制,我们分别观察了缺氧(模拟海拔4000m高原)24h山羊血浆(HP),缺血1h(在上述条件下于缺氧24h末放血使血压维持在6.0kPa1h)山羊血浆(IP)和再灌注回输放出血液后24h)山羊血浆(RP)对中性粒细胞(PMN)及培养的肺动脉内皮细胞(PAEC)的作用,PMN在分别含HP、IP和RP的培养中温育1h末,细胞活力明显升高(P〈0.001),其升高  相似文献   
100.
猴表皮干细胞的分离和培养   总被引:3,自引:1,他引:3       下载免费PDF全文
目的: 探索猴表皮干细胞分离纯化和培养方法。 方法: 将猴皮肤标本剪成皮条,加入0.25%胰酶浸泡过夜;然后去除角质层,刮上皮面获取表皮细胞进行培养。取第2-4代的细胞,经消化后,用Ⅳ型胶原黏附法获得为快吸附的表皮细胞。对快吸附的表皮细胞行流式细胞仪、免疫组化和RT-PCR检测。 结果: 快吸附细胞从mRNA转录水平及蛋白表达水平均呈现表皮干细胞的特性:β1整合素、K15和α6整合素阳性,而CD71和K1/K10阴性。 结论: 所采用的分离纯化方法和培养条件适合猴表皮干细胞的分离纯化及生长。  相似文献   
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