共查询到20条相似文献，搜索用时 31 毫秒
1.
Jin-jing Wang Feng Ye Li-jia Cheng Yu-jun Shi Ji Bao Huai-qiang Sun Wei Wang Peng Zhang Hong Bu 《Journal of Zhejiang University. Science. B》2009,10(5):355-367
Objective: Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques. The aim of this study is to investigate the effect of connective tissue growth factor (CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells (MSCs). Methods: A CTGF-expressing plasmid (pCTGF) was constructed and transfected into MSCs. Then expressions of bone morphogenesis-related genes, proliferation rate, alkaline phosphatase activity, and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs. Results: Overexpression of CTGF was confirmed in pCTGF-MSCs. pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs (P<0.05). CTGF induced a 7.5-fold increase in cell migration over control (P<0.05). pCTGF transfection enhanced the expression of bone matrix proteins, such as bone sialo-protein, osteocalcin, and collagen type I in MSCs. The levels of alkaline phosphatase (ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0- and 3.0-fold higher than those of MSCs cultured in OS-medium, significantly higher than those of mock-MSCs and normal control MSCs (P<0.05). Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules. Conclusion: Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs, and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering. 相似文献
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Accumulating evidence indicates that endostatin inhibits fibrosis. However, the mechanism is yet to be clarified. The aim of this study is to evaluate the effect of endostatin on platelet-derived growth factor-BB (PDGF-BB)-or transforming growth factor β1 (TGF-β1)-induced fibrosis in cultured human skin fibroblasts, and to further examine the molecular mechanisms involved. Human dermal fibroblasts were cultured in Dulbecco’s modified Eagle’s medium (DMEM) and serum-starved for 48 h before treatment. Cells were grouped as follows: “PDGF-BB”, “PDGF-BB+ endostatin”, “TGF-β1”, “TGF-β1+endostatin”, “endostatin”, and “blank control”. The fibroblasts were stimulated with either TGF-β1 or PDGF-BB for 72 h in order to set up the fibrosis model in vitro. The cells were co-cultured with either TGF-β1 or PDGF-BB and endostatin and were used to check the inhibiting effect of endostatin. A blank control group and an endostatin group were used as negative control groups. The biomarkers of fibrosis, including the expression of collagen I, hydroxyproline, and α-smooth muscle actin (α-SMA), were evaluated using an enzyme-linked immunosorbent assay (ELISA) and Western blot. The expression of phosphorylated PDGF receptor β (p-PDGFRβ), PDGFRβ, phosphorylated extracellular signal-regulated kinase (p-ERK), and ERK was detected using Western blot and immunofluorescent staining was used to explore the mechanisms. Both PDGF-BB and TGF-β1 significantly up-regulated the expression of collagen I, hydroxyproline, and α-SMA. Endostatin significantly attenuated both the PDGF-BB- and TGF-β1-induced over-expression of collagen I, hydroxyproline, and α-SMA. PDGF-BB and TGF-β1 both promoted the expression of PDGFR, ERK, and p-ERK. Endostatin inhibited the expression of PDGFR and p-ERK but did not affect the expression of total ERK. Endostatin inhibited hypertrophic scar by modulating the PDGFRβ/ERK pathway. Endostatin could be a promising multi-target drug in future fibrosis therapy. 相似文献
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Objective:To investigate the effects of mycotoxin moniliformin (MON) on the metabolism of aggrecan and type II collagen in human chondrocytes in vitro and the relationship between MON and Kashin-Beck disease (KBD).Methods:Human chondrocytes were isolated and cultured on bone matrix gelatin to form an artificial cartilage model in vitro with or without MON toxin.Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.The expression of aggrecan and type II col... 相似文献
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目的：探讨甘草黄酮对紫外线照射无毛小鼠皮肤的防护作用及可能机制.方法：昆明种小鼠40只,随机分成4组,每组10只：对照组、模型组、基质组、甘草黄酮组.模拟日光辐射制备小鼠皮肤光老化模型.在辐射同时,基质组外用基质乳膏,甘草黄酮组外用甘草黄酮乳膏.观察各组小鼠皮肤组织结构,SOD、GSH-Px、CAT、MDA、Hpy含量及Ⅰ型胶原蛋白mR-NA的相对定量的变化.结果：甘草黄酮组较模型组、基质组皮肤组织中MDA水平显著下降（P＜0.01）,SOD、GSH-Px、CAT、Hyp水平及Ⅰ型胶原蛋白相对含量显著升高（P＜0.01）.光学显微镜显示,模型组和基质组皮肤组织病理切片呈现明显光老化损伤,表皮结构不完整,出现炎性细胞浸润;对照组和甘草黄酮组表皮组织结构完整,各层细胞清晰.结论：甘草黄酮对紫外线照射小鼠皮肤具有防护作用,其机制与增强皮肤组织抗氧化能力,促进氧自由基清除,以及促进皮肤胶原蛋白合成有关. 相似文献
6.
Bing Zhang Pei-biao Zhang Zong-liang Wang Zhong-wen Lyu Han Wu 《Journal of Zhejiang University. Science. B》2017,18(11):963-976
Objective
A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated.Methods
A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits.Results
After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2–8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA.Conclusions
The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.7.
Zhi Yang Miao Liu Yin-gang Zhang Xiong Guo Peng Xu 《Journal of Zhejiang University. Science. B》2009,10(3):188-192
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
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目的：从新生SD大鼠脑室下区分离并培养神经干细胞．观察其生长、增殖及分化．方法：采取无血清培养和单细胞克隆技术．采用原代贴壁及传代悬浮方法．培养获得细胞克隆．利用免疫细胞化学方法鉴定神经干细胞．结果：从新生SD大鼠脑室下区分离的组织，经原代和传代培养均可形成细胞克隆．且具有增殖能力．原代和传代细胞巢蛋白(Nestin)、神经元特异性烯醇化酶(Neuron specific enolase．NSE)抗原呈阳性．神经干细胞可分化为神经元．结论：用上述方法分离的细胞具有自我更新能力和分化潜能以及很强的增殖能力．属于中枢神经系统的干细胞． 相似文献
11.
程玲玲 《孝感职业技术学院学报》2013,(4):107-109
目的：了解αB-晶体蛋白在乳腺癌组织中的表达情况,探讨αB-晶体蛋白与乳腺癌的发生、发展的关系。方法：随机抽取57例乳腺癌患者病理组织切片标本,利用免疫组化染色方法,观察αB-晶体蛋白在肿瘤组织中的表达情况。结果：αB-晶体蛋白在乳腺癌组织中表达阳性率明显高于在癌旁正常组织中表达的阳性率（P〈0．01）;在浸润性导管癌组织中的表达阳性率明显高于无浸润导管癌中的阳性率（P〈0．05）;αB-晶体蛋白表达阳性率与癌细胞的分化程度不具有统计学意义（P〉0．05）。结论：αB-晶体蛋白的表达与乳腺癌的发生和发展有关,但与乳腺癌的分化程度无关。 相似文献
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Yang RN Ye F Cheng LJ Wang JJ Lu XF Shi YJ Fan HS Zhang XD Bu H 《Journal of Zhejiang University. Science. B》2011,12(7):582-590
The osteoinduction of porous biphasic calcium phosphate ceramics (BCP) has been widely reported and documented, but little
research has been performed on rodent animals, e.g., mice. In this study, we report osteoinduction in a mouse model. Thirty
mice were divided into two groups. BCP materials (Sample A) and control ceramics (Sample B) were implanted into the leg muscle,
respectively. Five mice in each group were killed at 15, 30, and 45 d after surgery. Sample A and Sample B were harvested
and used for hematoxylin and eosin (HE) staining, immunohistochemistry (IHC) staining, and Alizarin Red S staining to check
bone formation in the biomaterials. Histological analysis showed that no bone tissue was formed 15 d after implantation (0/5)
in either of the two groups. Newly-formed bone tissues were observed in Sample A at 30 d (5/5) and 45 d (5/5) after implantation;
the average amounts of newly-formed bone tissues were approximately 5.2% and 8.6%, respectively. However, we did not see any
bone tissue in Sample B until 45 d after implantation. Bone-related molecular makers such as bone morphogenesis protein-2
(BMP-2), collagen type I, and osteopontin were detected by IHC staining in Sample A 30 d after implantation. In addition,
the newly-formed bone was also confirmed by Alizarin Red S staining. Because this is the report of osteoinduction in the rodent
animal on which all the biotechnologies were available, our results may contribute to further mechanism research. 相似文献
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Sen Yang Li-juan Guo Qing-hong Gao Ming Xuan Ke Tan Qiang Zhang Yu-ming Wen Chang-mei Wang Xiu-fa Tang Xiao-yi Wang 《Journal of Zhejiang University. Science. B》2010,11(10):745-753
Mucoepidermoid carcinoma undergoes uniquely vigorous angiogenic and neovascularization processes, possibly due to proliferation
of vascular endothelial cells (ECs) induced by mucoepidermoid carcinoma cells (MCCs) in their three-dimensional (3D) microenvironment.
To date, no studies have dealt with tumor cells and vascular ECs from the same origin of mucoepidermoid carcinoma using the
in vitro 3D microenvironment model. In this context, the current research aims to observe neovascularization with mucoepidermoid
carcinoma microvascular ECs (MCMECs) conditioned by the microenvironment in the 3D collagen matrix model. We observed the
growth of MCMECs purified by immunomagnetic beads and induced by MCCs, and characteristics of tubule-like structures (TLSs)
formed by induced MCMECs or non-induced MCMECs. The assessment parameters involved the growth curve, the length, the outer
and inner diameters, and the wall thickness of the TLSs, and the cell cycle. Results showed that MCCs induced formation of
the TLSs in the 3D collagen matrix model. A statistically significant difference was noted regarding the count of TLSs between
the control group and the induction group on the 4th day of culture (t=5.00, P=0.001). The outer and inner diameters (t
1=5.549, P
1=0.000; t
2=10.663, P
2=0.000) and lengths (t=18.035, P=0.000) of the TLSs in the induction group were statistically significant larger than those in the control group. The TLSs
were formed at the earlier time in the induction group compared with the control group. It is concluded that MCCs promote
growth and migration of MCMECs, and formation of the TLSs. The 3D collagen matrix model with MCMECs induced by MCCs in the
current research may be a favorable choice for research on pro-angiogenic factors in progression of mucoepidermoid carcinoma. 相似文献
14.
Background： Endothelial and smooth muscle cells were used as seeding cells and heterogeneous acellularized matrix was used as scaffold to construct the tissue-engineered graft. Methods： A 2 weeks piglet was selected as a donor of seeding cells. Two-centimetre length of common carotid artery was dissected. Endothelial cells and smooth muscle cells were harvested by trypsin and collagenase digestion respectively. The isolated cells were cultured and expanded using routine cell culture technique. An adult sheep was used as a donor of acellularized matrix. The thoracic aorta was harvested and processed by a multi-step decellularizing technique to remove the original cells and preserve the elastic and collagen fibers. The cultured smooth muscle cells and endothelial cells were then seeded to the acellularized matrix and incubated in vitro for another 2 weeks. The cell seeded graft was then transplanted to the cell-donated piglet to substitute part of the native pulmonary artery. Results： The cultured cells from piglet were characterized as endothelial cells by the presence of specific antigens vWF and CD31, and smooth muscle cells by the presence of specific antigen a-actin on the cell surface respectively with immunohistochemical technique. After decellularizing processing for the thoracic aorta from sheep, all the cellular components were extracted and elastic and collagen fibers kept their original morphology and structure. The maximal load of acellular matrix was decreased and 20% lower than that of untreated thoracic aorta, but the maximal tensions between them were not different statistically and they had similar load-tension curves. Three months after transplantation, the animal was sacrificed and the graft was removed for observation. The results showed that the inner surfaces of the graft were smooth, without thrombosis and calcification. Under microscopy, a great number of growing cells could be seen and elastic and collagen fibers were abundant. Conclusion： Cultured self-derived endothelial and smooth muscle cells could be used as seeding cells and heterogeneous acellularized matrix could be used as scaffold in constructing tissue-engineered graft. 相似文献
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组织工程是一个迅速发展的领域。随着组织工程的发展,支架的构造已趋向于模拟天然细胞外基质的结构,即含有纳米纤维结构。相对传统类型的支架,纳米纤维支架更有利于细胞的粘附、增殖、生长及组织的构建。目前制备纳米纤维支架的技术方法主要有：静电纺丝、分子自组装和热致相分离等。本文主要综述了这几种纳米纤维支架的制备方法及其影响因素的研究进展。 相似文献
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杨春蓉 《福建工程学院学报》2011,9(3):205-208
通过仿生合成、冷冻干燥及交联处理方法,制备出一种以双相磷酸钙、胶原和碳酸羟基磷灰石三组分为主要成分的新型三维骨组织工程支架。采用SEM、EDX和FTIR等测试技术对支架的性能特征进行分析。结果表明:制备的复合支架具有三维多孔的有序结构。双相磷酸钙作为力学支撑骨架有助于胶原网络基质形成特定的形状并使之具有一定的力学强度。在矿化过程中,羟基磷灰石矿物晶体在胶原的反应成核位点通过化学键合作用进行自组装。交联的胶原及其仿生矿化形成的碳酸羟基磷灰石可使支架具有良好的生物学性能,有望成为广阔临床应用前景的骨组织工程植入材料。 相似文献
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胶原-磷酸钙复合物是最有应用前景的骨组织工程框架材料.论文通过扫描电镜、红外光谱等方法证明了复合物中的胶原与钙离子间存在配位作用.结果表明:矿化反应体系通过载钙胶原的自组装、磷酸钙矿化的相继过程,形成具有层状结构的复合物.分析了胶原生物矿化的机制. 相似文献
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应用由乳化-扩散方法制备的功能PLGA纳米颗粒的药物发送系统(英文) 总被引：4，自引：0，他引：4
运用功能纳米颗粒的药物发送系统是一种具有发展前景的途径,因为它减少了副反应并减轻病痛 Poly(D,L lactide co glycolide)(PLGA)纳米颗粒的尺寸是80nm,它的制备是通过乳化扩散方法,并应用Poloxamer188作为稳定剂 所制备的纳米颗粒具有疏水核作为药物的载体,而其冠状亲水表面可避免形成网状内皮系统(RES) 作为生物医学应用的第一个例子是PLAG纳米颗粒包含雌激素,它对于受到意外伤害而抑制不安情绪具有局限性 研究指出:局部地发送具有雌激素的PLGA纳米颗粒将激烈减少新内膜的形成程度 其次是应用经过修改的PLAG纳米颗粒发送系统专用于骨治疗的药已经实现,它与骨有高度的相似 已经证明:与双磷酸(bisphosphonate)相结合的PLGA纳米颗粒,参入到鼠的静脉内之后,将可累积在鼠骨内 相似文献
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讨论了矩阵方程X+A*X-nA=I在A为正定矩阵和酉矩阵时的正定解的存在性、唯一性、误差估计及存在正定解的必要条件,并且构造了数值求解的迭代方法. 相似文献
20.
目的：采用实时荧光定量聚合酶链式反应（polymerase chain reaction,PCR）技术,研究P2X受体在大鼠神经胶质瘤和嗜铬细胞瘤及原代培养皮层神经元和星形胶质细胞上的表达差异。方法：取新生1-2 d SD大鼠大脑皮层,分离纯化神经元和星形胶质细胞,并采用实时荧光定量PCR技术,比较P2X受体在大鼠胶质瘤C6细胞、大鼠肾上腺嗜铬细胞瘤PC-12细胞、星形胶质细胞和皮层神经元上的表达差异。结果：C6细胞P2X2、P2X3和P2X5表达水平显著高于星形胶质细胞,P2X4、P2X6和P2X7表达水平显著低于星形胶质细胞,PC-12细胞P2X1、P2X2、P2X3和P2X6表达水平显著高于皮层神经元,P2X5和P2X7表达水平则显著低于皮层神经元。此外,还发现P2X2、P2X5和P2X6在C6和PC-12细胞上的表达水平存在显著差异。结论：大鼠胶质瘤和嗜铬细胞瘤细胞表达多种P2X受体,且与原代培养细胞存在表达差异,提示核苷酸介导的信号传递系统可能作为潜在的肿瘤治疗靶点。 相似文献