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1.
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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INTRODUCTION Costimulatory signals play a vital role in T cell activation. B7/CD28 and CD40/CD40L have been well-established as important costimulatory pathways, with the blockade of either resulting in suppression or anergy of T cells associated with prolongation of graft survival (Akalin et al., 1996; Bolling et al., 1996; Kita et al., 1999; Reddy et al., 2001; Laumonier et al., 2003; Thiel et al., 2005). Cytotoxic T lymphocyte associated antigen-4 (CTLA4), a ligand for B7, de-…  相似文献   

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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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This study is aimed at investigating the potentials of ex vivo expansion and pluri-differentiation of cryopreservation of adult human bone marrow mesenchymal stem cells (hMSCs) into chondrocytes, adipocytes and neurocytes. Cryopreserved hMSCs were resuscitated and cultured for 15 passages, and then induced into chondrocytes, adipocytes and neurocytes with corresponding induction medium. The induced cells were observed for morphological properties and detected for expressions of type II collagen, triglyceride or neuron-specific enolase and nestin. The result showed that the resuscitated cells could differentiate into chondrocytes after exposure to transforming growth factor 61 (TGF-~0, insulin-like growth factor I (IGF-I) and vitamin C (Vc), and uniformly changed morphologically from a spindle-like fibroblastic appearance to a polygonal shape in three weeks. The induced cells were heterochromatic to safranin O and expressed cartilage matrix-procollagenal (If) mRNA. The resuscitated cells cultured in induction medium consisting of dexamethasone, 3-isobutyl-l-methylxanthine, indomethacin and IGF-I showed adipogenesis, and lipid vacuoles accumulation was detectable after 21 d. The resuscitated hMSCs were also induced into neurocytes and expressed nestin and neuron specific endolase (NSE) that were special surface markers associated with neural cells at different stage. This study suggested that the resuscitated hMSCs should be still a population ofpluripotential cells and that it could be used for establishing an abundant bMSC reservoir for further experiment and treatment of various clinical discases.  相似文献   

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目的:检测CD44v6mRNA和HSP70mRNA在胃癌组织中的表达,探讨CD44v6mRNA和HSP70mRNA在胃癌发生发展中的作用.方法:利用核酸原位杂交技术对39例胃癌组织进行检测.结果:CD44v6mRNA和HSP70mRNA在胃癌组织表达的阳性率都为61.54%(24/39),CD44v6mRNA和HSP70mRNA在高分化管状腺癌与低分化管状腺癌中的表达都有显著性差异(P<0.05),但HSP70mRNA在胃癌组织的表达与性别、年龄、浸润深度及淋巴结有无转移都无关(P>0.05),而CD44v6mRNA与淋巴结有无转移有关(P<0.05).结论:CD44v6mRNA和HSP70mRNA在胃癌组织都有较高的表达,两者均可作为评估胃癌预后的指标.  相似文献   

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目的探讨CD40-CD40配体相互作用对体外培养的人脐静脉内皮细胞(HUVEC)增殖及迁移的影响。方法采用Ⅱ型胶原酶消化法培养人脐静脉内皮细胞,以3H-胸腺嘧啶脱氧核苷(3H-TdR)、3H-亮氨酸(3H-Leu)掺入法分别测定HUVEC增殖,内皮细胞的迁移采用琼脂糖凝胶刮取法,倒置显微镜观察。结果CD40-CD40配体相互作用能明显促进HUVEC3H-TdR、3H-Leu的掺入,两者具有时间、剂量依赖性,CD40-CD40配体相互作用随CD40L浓度的增加及刺激时间延长(30h内),能明显增加内皮细胞迁移率,an-ti-CD40单克隆抗体能明显抑制上述效应。结论CD40-CD40配体相互作用能促进内皮细胞增殖、迁移。  相似文献   

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INTRODUCTIONHeadandneckcancersquamouscellcarci noma (HNSCC)isthefifthmostfrequentmalig nantneoplasmworld wide ;andischaracterizedbylocalinvasion ,disseminationtolocallymphnodeandfrequentrecurrenceattheprimarysiteoftumour.Despiteimprovementsindiagnosisandt…  相似文献   

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This study aimed to explore the molecular mechanism in tumor invasion and metastasis. The expression of matrix metalloproteinase-2, −9 (MMP-2, MMP-9), tissue inhibitor-1 of matrix metalloproteinase (TIMP-1), cell adhesion molecule 44 variant 6 (CD44v6), HER2/neu and p53 was investigated in 154 patients with head and neck squamous cell carcinoma (SCC) by ABC and ImmunoMax immunohistochemical method. Their clinical relevance and correlation were analysed. The expression of MMP-2, MMP-9, TIMP-1, CD44v6, HER2/neu and p53 was found in cancer cells in 87.01%, 85.71%, 68.18%, 98.05%, 55.19% and 50.65% cases respectively. Linear regression and correlation analysis revealed that there was close positive relationship (P<0.05) between the expression of MMP-2 and MMP-9, TIMP-1 and CD44v6, HER2/neu and MMP-9, MMP-2 and p53. Up-regulation of MMP-2 was accompanied by advanced T stage (P<0.01). There was also a trend of MMP-2 expression being related with tumor metastasis. Increased expression of HER2/neu was found in patients with tumor recurrence (P<0.05). The expression of TIMP-1 was higher in laryngeal cancer than that in pharyngeal cancer, and higher in keratinizing and non-keratinizing SCC than that in basaloid SCC (P<0.05). These findings suggested that MMP-2 and MMP-9, HER2/neu and MMP-9, MMP-2 and p53 had a coordinate function in aggression of tumor; that MMP-2 had a more important function than MMP-9 in tumor invasion and metastasis; and that HER2/neu might serve as a biomarker for poor prognosis in HNSCC. Project supported by Lübeck Medical University, Germany  相似文献   

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This paper aims to screen and identify sphere clone cells with characteristics similar to cancer stem cells in human gallbladder cancer cell line GBC-SD. GBC-SD cells were cultured in a serum-free culture medium with different concentrations of the chemotherapeutic drug cisplatin for generating sphere clones. The mRNA expressions of stem cell-related genes CD133, OCT-4, Nanog, and drug resistance genes ABCG2 and MDR-1 in sphere clones were detected by quantitative real-time polymerase chain reaction (PCR). Stem cell markers were also analyzed by flow cytometry and immunofluorescent staining. Different amounts of sphere clones were injected into nude mice to test their abilities to form tumors. Sphere clones were formed in serum-free culture medium containing cisplatin (30 μmol/L). Flow cytometry results demonstrated that the sphere clones expressed high levels of stem cell markers CD133+ (97.6%) and CD44+ (77.9%) and low levels of CD24+ (2.3%). These clones also overexpressed the drug resistance genes ABCG2 and MDR-1. Quantitative real-time PCR showed that sphere clones expressed stem cell genes Nanog and OCT-4 284 and 266 times, respectively, more than those in the original GBC-SD cells. Immunofluorescent staining showed that sphere clones overexpressed OCT-4, Nanog, and SOX-2, and low expressed MUC1 and vimentin. Tumor formation experiments showed that 1×103 sphere clone cells could induce much larger tumors in nude mice than 1×105 GBC-SD cells. In conclusion, sphere clones of gallbladder cancer with stem cell-like characteristics can be obtained using suspension cultures of GBC-SD cells in serum-free culture medium containing cisplatin.  相似文献   

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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   

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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   

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本文在链烷烃的分子图的基础上,切断分子图的任一条边(C-C键)成两个子图,以切断边的顶点为起点,对这两个子图的路径顶点数Nc(即子图中任一顶点到起始顶点这一路径中所包含的顶点数)的平方倒数求和(∑1N2c)然后进一步构造出两类新的拓扑指数———邻接矩阵特征根(X1cc,X2cc),距离积方根连接性指数和(Xc);同时,本文探讨了这些指数与相应链烷烃的原子化热(HA)的关系,结果表明本文所提出的拓扑指数与相应的链烷烃的原子化热(HA)具有良好的结构———性质相关性.  相似文献   

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The objective was to investigate the expression of bone morphogenetic protein (BMP) family members in the mouse uterus during the estrous cycle by real-time polymerase chain reaction (PCR) and immunohistochemistry. Uterine samples from Swiss ICR mice were collected and dissected free of surrounding tissue. One uterine horn was snap frozen in liquid nitrogen immediately after collection and stored at −80 °C for RNA extraction, and the other was fixed in 40 mg/ml paraformaldehyde at room temperature for immunolocalization of BMP2 protein. Real-time PCR analysis showed that the expression level of Bmp2 was significantly higher at proestrus than at estrus and metestrus (P<0.05). The relative abundance of Bmp4 exhibited significant fluctuations, but there were no statistically significant differences between the expression levels of Bmp2 and Bmp4 (P>0.05). The expression levels of Bmpr1a and Bmpr2 remained unchanged during estrous cycles. However, the level of Bmpr1b mRNA decreased significantly at estrus (P<0.05), increasing subsequently at metestrus. Furthermore, the level of Bmpr1b mRNA was significantly lower than those of Bmpr1a and Bmpr2 mRNA at the corresponding stages (P<0.05). All three receptor-regulated Smads (R-Smads) detected were differentially expressed in the mouse uterus and the expression levels of Smad1 and Smad5 were significantly higher than that of Smad8 (P<0.05). In addition, the expression level of Smad4 did not change substantially throughout the estrous cycle. Immunohistochemical experiments revealed that BMP2 protein was differentially expressed and localized mainly in the uterine luminal and glandular epithelial cells throughout the estrous cycle. In conclusion, our results provide information about the variation in the mRNA levels of Bmp2 and Bmp4 and related components of the BMP signaling pathway. The data provide quantitative and useful information about the roles of endometrial BMP proposed and demonstrated by others, such as the degradation and remodeling of the endometrium.  相似文献   

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Evidence suggests that the deterioration of communication between the sympathetic nervous system and cardiovas-cular system always accompanies the aging of human and animals. Cardiac sympathetic norepinephrine (NE) transporter (NET) on presynaptic membrane is a predominant component to eliminate released NE in the synaptic cleff and maintains the sensitivity of the β-adrenergic receptor (β-AR). In the present study, we investigated NET and β1-AR mRNA levels and sympathetic nerve density in cardiac sympathetic ganglion and leff ventricular myocardium in 2- and 16-month-old rats with Northern blot analysis and immunohistochemistry. The expression levels of NET mRNA, NET protein and β1-AR mRNA in the ganglia or myocardia of 16-month-old rats were markedly reduced by 67%, 26%, and 43%, respectively, in comparison with those in 2-month-old rats. Our results also show that aging induces a strong decrease of the catecholaminergic nerve fiber density.  相似文献   

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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   

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A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes (Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve’s core, buffer, and experimental zones during overwintering periods of 2013 to 2015, a total of 113 food samples were analyzed for aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A using high performance liquid chromatography (HPLC). The contamination incidences vary among different zones and the mycotoxins levels of different food samples also presented disparity. Average mycotoxin concentration from rice grain was greater than that from other food types. Among mycotoxin-positive samples, 59.3% were simultaneously contaminated with more than one toxin. This study demonstrated for the first time that red-crowned cranes were exposed to mycotoxins in the Yancheng Biosphere Reserve and suggested that artificial wetlands could not be considered good habitats for the birds in this reserve, especially rice fields.  相似文献   

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Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the IN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions, the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens.  相似文献   

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