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91.
微创术对脑出血后脑水肿患者血浆明胶酶B的影响 总被引:1,自引:0,他引:1
目的探讨高血压性脑出血微创术对清除血肿后脑水肿患者血浆明胶酶B(MMP-9)的影响。方法127例脑出血患者随即分为内科治疗组60例、微创术血肿抽吸引流组67例;采用酶联免疫法(ELISA)测定脑出血后第3天、第7天和第21天血浆MMP-9含量。结果微创组和内科治疗组血浆中MMP-9含量均升高;两组治疗后第3、7天的含量与治疗前(发病24h内)比较,差异有统计学意义(P<0.05);两组治疗后不同时间点血浆中MMP-9含量比较,差异有统计学意义(P<0.05)。结论微创组能减少患者血浆MMP-9含量的增加。 相似文献
92.
目的探讨MTA1、MMP-9和TIMP-1蛋白与小儿神经母细胞瘤生物学行为之间的关系。方法运用免疫组化S—P法检测56例神经母细胞瘤组织中MTA1、MMP-9、TIMP—1蛋白的表达。结果56例神经母细胞瘤组织中37例MTA1阳性表达,阳性率为66.1%,MTA1高表达与神经母细胞瘤临床分期和转移关系密切(P〈0.05);39例MMP-9蛋白阳性表达,阳性率为69.6%,MMP-9高表达与神经母细胞瘤临床分期和转移关系密切(P〈0.05);27例TIMP—1蛋白阳性表达,阳性率为48.2%,TIMP-1低表达与神经母细胞瘤临床分期和转移关系密切(P〈0.05);神经母细胞瘤组织中MMP-9,TIMP-1蛋白表达呈负相关(P〈0.05)。结论MTA1、MMP-9和TIMP-1蛋白表达与神经母细胞瘤恶性程度、转移和预后关系密切,可作为判断预后的指标,并有望为肿瘤靶向治疗提供理论依据。 相似文献
93.
Panagiotis Lepetsos Andreas Pampanos Emmanouil Kanavakis Maria Tzetis Dimitrios Korres Athanasios G. Papavassiliou Nicolaos Efstathopoulos 《Journal of orthopaedic research》2014,32(9):1155-1160
94.
目的通过建立兔耳模型观察基质金属蛋白酶-1(matrixmetalloproteinase-1,MMP-1)及金属蛋白酶组织抑制剂-1(tissueinh|bitorofmetalloproteinase1,TIMP1)在病理性瘢痕皮回植术后组织中表达的变化,探讨瘢痕皮回植治疗病理性瘢痕的机制。方法建立兔耳病理性瘢痕模型。共分为3组:正常皮肤组(对照组,A组)、病理性瘢痕组(B组)及瘢痕皮回植组(c组)。切取标本行HE染色和Masson特殊组织化学染色及免疫组织化学染色,观察各组标本MMP-1、TIMP-1的表达情况。结果病理性瘢痕经瘢痕皮回植术后,MMP-1及TIMP-l均较A组明显升高(P〈O.01).MMP一1的表达较TIMP一1明显增强(P〈O.01)。结论瘢痕皮回植术治疗瘢痕的机制与瘢痕组织内MMP一1和TIMP一1相互作用的失衡有关。 相似文献
95.
Tetrandrine, a constituent of Chinese herb Stephania tetrandra, causes cell death in prostate cancer, but the molecular mechanisms leading to apoptosis is not known. Here we demonstrated that tetrandrine selectively inhibits the growth of prostate cancer PC3 and DU145 cells compared to normal prostate epithelial PWR-1E cells. Tetrandrine-induced cell death in prostate cancer cells is caused by reactive oxygen species (ROS)-mediated activation of c-Jun NH2-terminal kinase (JNK1/2). JNK1/2-mediated proteasomal degradation of c-FLIPL/S and Bcl2 proteins are key events in the sensitization of prostate cancer cells to Fas- and mitochondria-mediated apoptosis by tetrandrine. Tetrandrine-induced JNK1/2 activation caused the translocation of Bax to mitochondria by disrupting its association with Bcl2 which was accompanied by collapse of mitochondrial membrane potential (MMP), cytosolic release of cytochrome c and Smac, and apoptotic cell death. Additionally, tetrandrine-induced JNK1/2 activation increased the phosphorylation of Bcl2 at Ser70 and facilitated its degradation via the ubiquitin-mediated proteasomal pathway. In parallel, tetrandrine-mediated ROS generation also caused the induction of ligand-independent Fas-mediated apoptosis by activating procaspase-8 and Bid cleavage. Inhibition of procaspase-8 activation attenuated the cleavage of Bid, loss of MMP and caspase-3 activation suggest that tetrandrine-induced Fas-mediated apoptosis is associated with the mitochondrial pathway. Furthermore, most of the signaling effects of tetrandrine on apoptosis were significantly attenuated in the presence of antioxidant N-acetyl-l-cysteine, thereby confirming the involvement of ROS in these events. In conclusion, the results of the present study indicate that tetrandrine-induced apoptosis in prostate cancer cells is initiated by ROS generation and that both intrinsic and extrinsic pathway contributes to cell death. 相似文献
96.
The vascular endothelium is specifically sensitive to oxidative stress, and this is one of the mechanisms that causes widespread endothelial dysfunction in most cardiovascular diseases and disorders. Protection against reactive oxygen species (ROS)-mediated oxidative damage via antioxidant mechanisms is essential for tissue maintenance and shows therapeutic potential for patients suffering from cardiovascular and metabolic disorders. Salvianolic acid B (SalB), a natural bioactive component known from Traditional Chinese Medicine, has been reported to exert cellular protection in various types of cells. However, the underlying mechanisms involved are not fully understood. Here, we showed that SalB significantly promoted the migratory and tube formation abilities of human bone marrow derived-endothelial progenitor cells (BM-EPCs) in vitro, and substantially abrogated hydrogen peroxide (H2O2)-induced cell damage. SalB down-regulated Nox4 and eNOS, as well as nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase expression upon H2O2 induction that in turn prevents oxidative-induced endothelial dysfunction. Moreover, SalB suppressed the Bax/Bcl-xL ratio and caspase-3 activation after H2O2 induction. Furthermore, our results provide mechanistic evidence that activation of the mTOR/p70S6K/4EBP1 pathways is required for both SalB-mediated angiogenic and protective effects against oxidative stress-induced cell injury in BM-EPCs. Suppression of MKK3/6-p38 MAPK-ATF2 and ERK1/2 signaling pathways by SalB significantly protected BM-EPCs against cell injury caused by oxidative stress via reduction of intracellular ROS levels and apoptosis. Taken together, by providing a mechanistic insight into the modulation of redox states in BM-EPCs by SalB, we suggest that SalB has a strong potential of being a new proangiogenic and cytoprotective therapeutic agent with applications in the field of endothelial injury-mediated vascular diseases. 相似文献
97.
Min Yang Anup Ramachandran Hui-Min Yan Benjamin L. Woolbright Bryan L. Copple Peter Fickert Michael Trauner Hartmut Jaeschke 《Toxicology letters》2014
Osteopontin (OPN) is a chemotactic factor which can be cleaved to the pro-inflammatory form by matrix metalloproteinases (MMPs). To test the hypothesis that OPN can modulate inflammatory liver injury during cholestasis, wild-type (WT) C57BL/6 and OPN knockout (OPN-KO) mice underwent bile duct ligation (BDL). OPN-KO mice showed significant reduction in liver injury (plasma ALT and necrosis) and neutrophil recruitment compared with WT animals at 24 h but not 72 h after BDL. In WT mice, a 4-fold increase in hepatic MMP-3 mRNA and elevated MMP activities and cleaved OPN levels were observed in bile. WT mice subjected to BDL in the presence of the MMP inhibitor BB-94 showed reduced liver injury, less neutrophil extravasation and diminished levels of cleaved OPN in bile. Thus, during obstructive cholestasis, OPN released from biliary epithelial cells could be cleaved by MMPs in bile. When the biliary system leaks, cleaved OPN enters the parenchyma and attracts neutrophils. In the absence of OPN, other chemoattractants, e.g. chemokines, mediate a delayed inflammatory response and injury. Taken together, our data suggest that OPN is the pro-inflammatory mediator that initiates the early neutrophil-mediated injury phase during obstructive cholestasis in mice. 相似文献
98.
Xing Li Lin Zhang Xinjuan Yin Zhan Gao Huanhuan Zhang Xiaozhuan Liu Xinjuan Pan Ning Li Zengli Yu 《Toxicology letters》2014
The regulation of extracellular matrix (ECM) by retinoic acid (RA) is interesting in light of the fact that the ECM plays an essential role in morphogenesis and palatal shelf elevation. In the current study, we explored the effect of RA overexposure on ECM and the probable mechanisms in cultured human fetal palate mesenchymal cells (hFPMCs). RA dose-dependently inhibited cell proliferation and mRNA and protein levels of ECM components fibronectin, tenascin C and fibrillin-2. Zymography revealed that MMP-2 activity was suppressed by RA. Further analysis revealed that mRNA levels of MMP2 and TIMP2 were decreased, while the MMP2/TIMP2 mRNA ratio was increased, which might facilitate the ECM degradation. Because of the pivotal role of TGF-β/Smad pathway in palatogenesis we therefore checked the effect of RA on TGF-β/Smad signaling. The results indicated RA treatment increased Smad7 expression and decreased the levels of TGF-β1, TGF-β3, TGF-β type II receptor (TβRII) and phosphorylated Smad2 and Smad3. Activation of the Smad pathways by either exogenous TGF-β3 or recombinant adenoviruses for Smad3 attenuated RA-induced inhibition of cell proliferation and ECM components and rescued the RA-altered MMP2/TIMP2 mRNA ratio. In conclusion, these findings suggested that RA overexposure inhibited cell proliferation and disrupted the ECM network through down-regulation of TGF-β/Smad pathway. 相似文献
99.
Synthesis,Biological Evaluation,and Docking of Dihydropyrazole Sulfonamide Containing 2‐hydroxyphenyl Moiety: A Series of Novel MMP‐2 Inhibitors
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Peng‐Fei Wang Han‐Yue Qiu Shahla Karim Baloch Hai‐Bin Gong Zhong‐Chang Wang Hai‐Liang Zhu 《Chemical biology & drug design》2015,86(6):1405-1410
In this study, we synthesized a series of dihydropyrazole sulfonamide derivatives containing 2‐hydroxyphenyl moiety as antitumor agents to target the matrix metalloproteinase‐2 (MMP‐2). All of the synthesized compounds were examined by bioactivity assays, in which compound 4c turned out as a potential antagonist of MMP‐2 along with potent anticancer activity against four tumor cell lines. Structure–activity relationship analysis was also performed to examine how structural changes impacted the bioactivity. Suggested to be caused by the induction of apoptosis, the antitumor mechanism of 4c was further confirmed by PI combining with annexin V‐FITC staining assay using flow cytometry analysis. These new findings along with molecular docking observations suggested that compound 4c could be developed as a potential anticancer agent. 相似文献
100.
Synthesis and Evaluation of Trehalose‐Based Compounds as Novel Inhibitors of Cancer Cell Migration and Invasion
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Yu‐Jing Liu Lian‐Ping Ge Xiu‐Zhen Han Zhao‐Peng Liu 《Chemical biology & drug design》2015,86(5):1017-1029
As a continuous research for the discovery of trehalose‐based anti‐invasive agents, we developed a convenient synthetic approach for the preparation of 6,6′‐dideoxy‐6,6′‐bis(acylamino)‐α,α‐D‐trehaloses. A series of trehalose‐based amides were prepared through the trityl protection of the two primary hydroxyls of α,α‐D‐trehalose, benzoylation, the removal of the trityl protective group, mesylation, azidation, catalytic hydrogenation in the presence of hydrochloride, coupling reaction with a variety of acids, and subsequent debenzoylation and deacetylation in some cases. Compound 8b , 6,6′‐dideoxy‐6,6′‐bis(2‐hydroxybenzamide)‐ α , α ‐D‐trehalose, was just as potent as the natural brartemicin against the invasion of murine colon 26‐L5 cells. It exhibited no cytotoxicity on human breast adenocarcinoma MDA‐MB‐231 and murine colon 26‐L5 cells. It can significantly inhibit the migration and invasion of the MDA‐MB‐231 cells. The anti‐invasive effect of 8b was possibly related to its inhibitory activity on MMP‐9, its suppression on the expression of MMP‐9 and VEGF, and its deactivation of Akt. 相似文献