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1.
目的:探讨外源性EGFP基因转染修饰兔骨髓间充质干细胞(m esenchymal stem cells,MSCs)的可行性。方法:用增强型荧光绿色蛋白(enhanced green fluorescent protein,EGFP)作为报告基因,以脂质体法转染骨髓间充质干细胞,观察转染结果、表达情况及对靶细胞活力的影响。结果:经荧光显微镜下观察证实:成功地对骨髓间充质干细胞实现了基因转染。结论:兔骨髓间充质干细胞能够在体外适宜的条件下进行长期培养;骨髓间充质干细胞可直接作为基因靶细胞,建立稳定表达EGFP的骨髓间充质干细胞系具有可行性,为进一步做标记的MSCs细胞的移植研究奠定基础。  相似文献   

2.
Objective: We investigated the effects of intermittent negative pressure on osteogenesis in human bone marrow-derived stroma cells (BMSCs) in vitro. Methods: BMSCs were isolated from adult marrow donated by a hip osteoarthritis patient with prosthetic replacement and cultured in vitro. The third passage cells were divided into negative pressure treatment group and control group. The treatment group was induced by negative pressure intermittently (pressure: 50 kPa, 30 rain/times, and twice daily). The control was cultured in conventional condition. The osteogenesis of BMSCs was examined by phase-contrast mi-croscopy, the determination of alkaline phosphatase (ALP) activities, and the immunohistochemistry of collagen type I. The mRNA expressions of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) in BMSCs were analyzed by real-time poly-merase chain reaction (PCR). Results: BMSCs showed a typical appearance of osteoblast after 2 weeks of induction by intermit-tent negative pressure, the activity of ALP increased significantly, and the expression of collagen type 1 was positive. In the treatment group, the mRNA expression of OPG increased significantly (P<0.05) and the mRNA expression of OPGL decreased significantly (P<0.05) after 2 weeks, compared with the control. Conclusion: Intermittent negative pressure could promote os-teogenesis in human BMSCs in vitro.  相似文献   

3.
目的:为探讨糖尿病患者易患动脉粥样硬化是否与结缔组织生长因子有关以及可能的干预药物.方法:建立大鼠糖尿病模型,随机分为正常对照组、糖尿病组、糖尿病盐酸氨基胍治疗组和糖尿病葛根素治疗组.应用逆转录聚合酶链式反应检测各组大鼠主动脉结缔组织生长因子mRNA表达水平.结果发现,糖尿病组大鼠主动脉结缔组织生长因子mRNA明显高于对照组(P＜0.01),葛根素治疗组和氨基胍治疗组结缔组织生长因子mRNA明显低于糖尿病组(P＜0.01),氨基胍治疗组、葛根素治疗组与对照组比较有显著差异(P＜0.05).结果:结缔组织生长因子过多表达与糖尿病患者易患动脉粥样硬化有关.结论:氨基胍、葛根素可降低糖尿病大鼠主动脉结缔组织生长因子mRNA过多表达.  相似文献   

4.
以麦冬甾体皂苷为模型药物,以明胶为载体原料制备载药微球,并研究其对成骨细胞的调控作用。首先采用双乳化-化学交联技术构建载药明胶微球,再对其释药特点、调控成骨细胞生理功能的效应等方面开展研究。结果发现构建的载药微球不仅有效缓解药物突释现象并延长药物释放时间,而且可以有效刺激成骨细胞增殖、碱性磷酸酶分泌及矿化,促其向骨组织分化。  相似文献   

5.
Incorporation of a tendon graft within the bone tunnel represents a challenging clinical problem. Successful anterior cruciate ligament (ACL) reconstruction requires solid healing of the tendon graft in the bone tunnel. Enhancement of graft healing to bone is important to facilitate early aggressive rehabilitation and a rapid return to pre-injury activity levels. No convenient, effective or inexpensive procedures exist to enhance tendon-bone (T-B) healing after surgery. Low-intensity pulsed ultrasound (LIPUS) improves local blood perfusion and angiogenesis, stimulates cartilage maturation, enhances differentiation and proliferation of osteoblasts, and motivates osteogenic differentiation of mesenchymal stem cells (MSCs), and therefore, appears to be a potential non-invasive tool for T-B healing in early stage of rehabilitation of ACL reconstruction. It is conceivable that LIPUS could be used to stimulate T-B tunnel healing in the home, with the aim of accelerating rehabilitation and an earlier return to normal activities in the near future. The purpose of this review is to demonstrate how LIPUS stimulates T-B healing at the cellular and molecular levels, describe studies in animal models, and provide a future direction for research.  相似文献   

6.
Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   

7.

Objective  

To explore the effects of insulin-like growth factor-1 (IGF-1) on migration, proliferation and differentiation of mesenchymal stem cells (MSCs).  相似文献   

8.
Study on the neurotoxic effects of low-level lead exposure in rats   总被引：10，自引：0，他引：10  
Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.  相似文献   

9.
INTRODUCTION Congestive heart failure is the end stage of manycardiovascular diseases. Myocardial infarction (MI)is a life-threatening event that may cause suddencardiac death and heart failure. Despite considerableadvances in diagnosis and treatment of heart disease,cardiac dysfunction after MI is still the majorworldwide cardiovascular disorder. Damaged myo-cardium after acute MI is gradually replaced by fi-brotic noncontractile cells to form scar tissue. Thedeveloping ventricul…  相似文献   

10.
目的：探讨藻酸双脂钠（PSS）治疗急性脑梗死患者血液成分变化及疗效。方法：急性脑梗死患者158例，随机分为两组。对照组：78例，常规治疗；治疗组：80例，在常规治疗基础上，应用藻酸双脂钠注射液100mg加入0．9％氯化钠静脉滴注，每日一次，连续观察14d。对比分析二组治疗前后脂蛋白（a）、血脂、纤维蛋白原等血液流变学指标．并动态观察治疗前后临床神经功能缺损评分。结果：藻酸双脂钠可降低全血粘度、血浆粘度、血小板聚集率、纤维蛋白原及血清TC、TG、LDL，与治疗前比较有显著性改变（P〈0．01或P〈0．05）；与对照组比较有显著性差异（P〈0．01或P〈0．05）．但对脂蛋白（a）无影响；近期预后较常规治疗组好（P〈0．05）．结论：藻酸双脂钠可改善血液高粘滞状态，起到降低纤维蛋白原、抗血小板聚集作用，可改善近期临床神经功能缺损程度。  相似文献   

11.
Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=l 7). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF Of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn I) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P＜0.05)].Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21 cm and 0.74±0.13 cm, and remarkably lower than those of the model group, which were 1.64±0.14 cm and 1.19±0.12 cm (P＜0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group,which was 53±6% (P＜0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%),the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.  相似文献   

12.
Objective: To explore the effects of cytomegalovirus (CMV) infection on rejection-related gene expression in the endothelial cells of renal transplantation recipients. Methods: Endothelial cells (ECs) were cultured and stimulated by a variety of factors: A, normal control group; B, inactivated human cytomegalovirus (HCMV) infection group; C, HCMV infection group; D, HCMV supematant infection group; and E, ganciclovir HCMV group. Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompability complex (MHC) class Ⅰ and class Ⅱ antigens was detected by flow cytometry (FCM) and immuno-histochemistry. Results: We found characteristic CMV-infected ECs in this study. There were no significant differences among groups A, B and D (P>0.05). Although the expression levels of ICAM-1 were not significantly different between groups C and E (P>0.05), the ICAM-1 expression in these two groups was significantly higher than that in group A (P<0.05). ICAM-1 expression was detected in groups C and E, while there was no expression in groups A, B and D. Furthermore, there was no significant difference of ICAM-1 mRNA expression between groups C and E (P>0.05). Human leucocyte antigen (HLA)-ABC expression was detected in all the groups, while HLA-DR expression was only detected in groups C and E. There were no significant dif-ferences of HLA-ABC and HLA-DR expression among groups A, B and D (P>0.05). However, the HLA-ABC and HLA-DR expression levels in groups C and D were higher than those of the remaining groups previously reported (P<0.05). Meanwhile, the HLA-ABC and HLA-DR expression levels in group E were lower than those of group C (P<0.05). Conclusion: CMV could up-regulate the expression levels of ICAM-1 and MHC antigens, which was closely related to allograft rejection.  相似文献   

13.
This study was aimed to investigate the level of sEGF in CAG with different therapies of either Chinese traditional medicine or western medicine. Patients were divided into spleen-reinforcingⅠ, spleen-reinforcing Ⅱ,dampness-resolving and western medicine group by Differentiation Syndrome. Healthy volunteers acted as controls. The sEGF was investigated before and after treatment. The level of sEGF in CAG was higher than that in control group(P<0.01). In patients of spleen-reinforcingⅠgroup and spleen-reinforcing Ⅱgroup, the symptoms and pathological manifestations were improved dramatically (P<0.01) and sEGF dropped markedly after treatment(P<0.01 and P<0.05).The level of sEGF in the dampness-resolving group increased after treatment (P<0.05). But the level of sEGF in the western-medicine group dropped a little after treatment (P>0.05). The inflammation of gastric mucosa may cause the elevation of sEGF in CAG reflectively. After being effectively treated with Chinese traditional medicine, the symptoms of CAG improved simultaneously with the return of sEGF. SEGF is a sensitive index to prognosis of CAG.  相似文献   

14.
Objective:To investigate the relationship between the fatty acid-binding protein 4(FABP4)and colorectal cancer(CRC).Methods:Using an enzyme-linked immunosorbent assay(ELISA),we measured the expression of FABP4 in plasma of50 patients who underwent surgery for CRC from October 2017 to May 2018 and 50 healthy controls.The content of the visceral fat area(VFA)as seen with abdominal computed tomography(CT)scanning was measured by ImageJ software.The expression levels of FABP4,E-cadherin,and Snail proteins in CRC and adjacent tissues were determined by immunohistochemistry.Results:The mean concentration of plasma FABP4 of CRC patients was higher than that of the control group(22.46 vs.9.82 ng/m L;P<0.05).The concentration of plasma FABP4 was related to the tumor,node,metastatis(TNM)stage and lymph node metastasis and was independent of age,body mass index(BMI),tumor size and location,and the degree of differentiation of CRC.The concentration of plasma FABP4 was positively correlated with high VFA and lipoprotein-a(LPA)(P<0.05);but it was not correlated with total cholesterol(TG),total triglyceride(TC),low-density lipoprotein(LDL),high-density lipoprotein(HDL),or apolipoprotein AI(Apo-AI).The expression of FABP4 protein in CRC tissues was positively correlated with the degree of CRC differentiation,tumor stage,and lymph node metastasis.The level of FABP4 protein was negatively correlated with E-cadherin protein(r=-0.3292,P=0.0196)and positively correlated with Snail protein(r=0.5856,P<0.0001).Conclusions:High LPA and VFA were risk factors for increased plasma FABP4 in CRC patients.FABP4 protein was highly expressed in CRC tissues and associated with TNM stage,differentiation,and lymph node metastasis of CRC.The level of FABP4 in CRC tissue was correlated with E-cadherin and Snail expression,suggesting that FABP4 may promote CRC progression related to epithelial-mesenchymal transition(EMT).  相似文献   

15.
The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(II) is significantly higher than that of the cells treated with Fe(III) (P<0.05). Fe(II) at a concentration >1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(III). LDH release investigation suggests that Fe(II) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(II) were higher than those of the cells treated with Fe(III), although both of them increased with raising iron supply levels. The results indicate that both Fe(II) and Fe(III) could reduce the cellular antioxidase gene expression at high levels. Project supported by the International Cooperative Project from the Ministry of Science and Technology of China (No. 2006DFA31030), the Bureau of Science and Technology of Zhejiang Province (No. 2006C32019) and HarvestPlus-China (No. 8022), and the Program for Changjiang Scholars and Innovative Research Team in University of China (No. IRT0536)  相似文献   

16.
研究目的：本研究应用海藻酸钠-壳聚糖微囊保护成骨细胞,接种到β-磷酸三钙/磷酸钙骨水泥（β-TCP/CPC）浆料中,使β-TCP/CPC骨修复材料具有一定的细胞活性,同时提高固化后材料的孔隙率和孔径,以最终实现提高β-TCP/CPC骨水泥的降解速度,加快成骨和骨修复。创新要点：本研究首次应用海藻酸钠-壳聚糖微胶囊包封成骨细胞与CPC浆料复合,复合后实现自动细胞释放,释放出的细胞具有良好的生物学活性。研究方法：（1）高压静电成囊法制备载小鼠成骨前体细胞（MC3T3-E1）的海藻酸钙和海藻酸钠-壳聚糖微胶囊;（2）微囊化MC3T3-E1细胞,进行体外培养,使用细胞计数试剂盒（CCK-8）检测细胞活性,并用钙黄绿素-AM（Calcein-AM）和碘化丙啶（PI）进行活死细胞双重染色;（3）微囊化MC3T3-E1细胞与β-TCP/CPC浆料复合培养后,激光共聚焦扫描显微镜和环境扫描电子显微镜观测细胞在材料上的释放、粘附,CCK-8法检测材料上细胞的活力,碱性磷酸酶（ALP）检测观察细胞的分化状况,茜素红染色观察释放细胞的矿化能力。重要结论：海藻酸钠-壳聚糖微胶囊可作为可注射磷酸钙骨水泥内部接种成骨细胞并实现细胞释放的良好载体,释放出的成骨细胞具有良好的生物学活性。  相似文献   

17.
INTRODUCTION In 1998 gastrointestinal pathologists reached aconsensus on the definition of chronic atrophic gas- tritis (CAG), which was described as programmed loss of gastric gland and/or replacement by intestinal glands in gastric mucosa. CAG was recognized to be closely related with development of gastric cancer and listed as precancerous lesions in this meeting (Genta, 1998). According to Correa (1992)’s cascade of gas-tric carcinogenesis, gastric cancer was believed to develop fr…  相似文献   

18.
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19.
目的:探讨糖皮质激素对肾病综合征患儿血清钙、骨源性碱性磷酸酶的影响,了解患儿成骨细胞功能变化.方法:以血清钙、骨源性碱性磷酸酶为参数,对肾病综合征患儿治疗前及治疗后4周血清钙及骨源性碱性磷酸酶进行动态观察.结果:强的松治疗后血清钙及骨源性碱性磷酸酶与治疗前相比有显著差异,治疗后低于治疗前水平[血清钙(P＜0.01)、骨源性碱性磷酸酶(P＜0.01)].结论:皮质激素治疗可显著抑制肾病综合征患儿的成骨细胞功能,导致血清钙及碱性磷酸酶水平的降低.  相似文献   

20.
To examine the effects of co-culture with bone marrow mesenchymal stem cells on expansion of hematopoietic stem/progenitor cells and the capacities of rapid neutrophil engraftment and hematopoietic reconstitution of the expanded cells, we expanded mononuclear cells (MNCs) and CD34+/c-kit+ cells from mouse bone marrow and transplanted the expanded cells into the irradiated mice. MNCs were isolated from mouse bone marrow and CD34+/c-kit+ cells were selected from MNCs by using MoFlo Cell Sorter. MNCs and CD34+/c-kit+ cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (MSCs) under a two-step expansion. The expanded cells were then transplanted into sublethally irradiated BDF1 mice. Results showed that the co-culture with MSCs resulted in expansions of median total nucleated cells, CD34+ cells, GM-CFC and HPP-CFC respectively by 10.8-, 4.8-, 65.9- and 38.8-fold for the mononuclear cell culture, and respectively by 76.1-, 2.9-, 71.7- and 51.8-fold for the CD34+/c-kit+ cell culture. The expanded cells could rapidly engraft in the sublethally irradiated mice and reconstitute their hematopoiesis. Co-cultures with MSCs in conjunction with two-step expansion increased expansions of total nucleated cells, GM-CFC and HPP-CFC, which led us to conclude MSCs may create favorable environment for expansions of hematopoietic stem/progenitor cells. The availability of increased numbers of expanded cells by the co-culture with MSCs may result in more rapid engraftment of neutrophils following infusion to transplant recipients. Project supported by NIH-Blood, Heart & Lung (National Institute of Health, USA, IR 01 4L70593-01) and Zhejiang Provincial Science Foundation (No. 011103397), China  相似文献   

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