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991.
Objective: This study was performed to investigate bone deteriorations and the involvement of skeletal Eph/ephrin signaling pathway of GIOP aged mice in response to the treatment of genistein. Methods: The biomarkers in serum and urine were measured, tibias were taken for the measurement on gene and protein expression and histomorphology analysis, and femurs were taken for the measurement on bone Ca and three-dimensional architecture of trabecular bone. Results: Genistein showed a greater increase in bone Ca, BMD and significantly increased FGF-23 and OCN, reduced TRACP-5b, PTH and CTX in GIOP mice. Genistein reversed DXM-induced trabecular deleterious effects and stimulated bone remodeling. The treatment of DXM group with genistein significantly elevated the ratio of OPG/RANKL. Moreover, genistein administration down-regulated the mRNA and protein expression of Eph A2 and ephrin A2 in tibia of the GIOP mice. In contrast, the mRNA and protein expression of Eph B4 and ephrin B2 were increased in mice treated by DXM with genistein as compared to the DXM single treatment. Conclusions: DXM-induced trabecular bone micro-structure deterioration in aged mice was involved in the regulation of the Eph receptors and ephrin ligands. Genistein might represent a therapy with bone-forming as well as an anti-resorptive activity in GIOP mice. The underlying mechanism was mediated, at least partially, through regulation Eph/ephrin signaling.  相似文献   
992.
Oral squamous cell carcinoma (OSCC) ranks as the fifth most common cancer worldwide with poor prognosis. Recently, tumor necrosis factor receptor-associated factor 4 (TRAF4) has attracted increasing attenuation due to its overexpression in certain cancers. However, its function and underlying mechanism in OSCC remains elusive. In this study, the high expression of TRAF4 mRNA and protein levels was noted in OSCC cell lines. Its overexpression with pcDNA3.1-TRAF4 vector transfection dramatically promoted cell proliferation and inhibited cell apoptosis, indicating a pivotal role of TRAF4 in OSCC cell growth. Simultaneously, TRAF4 elevation also increased cell invasion and migration. Mechanism analysis confirmed that TRAF4 up-regulation induced the expression of β-catenin and the downstream target molecules of cyclinD1, c-myc, Bcl-2, MMP-9 and MMP-2, indicating that TRAF4 could induce the activation of Wnt/β-catenin pathway. After pretreatment with β-catenin siRNA, the pathway was remarkably silenced. Simultaneously, cell growth, invasion and migration induced by TRAF4 were strikingly abrogated, suggesting that TRAF4 may promote OSCC cell growth, invasion and migration by Wnt/β-catenin pathway. Together, this study confirmed that TRAF4 acts as an oncogene for the development and progression of OSCC. Therefore, our study may support a promising therapeutic target for the treatment of OSCC.  相似文献   
993.
Objective: To explore the expression of A-kinase anchor protein 95 (AKAP95), Cyclin D1, Cyclin E1, and Connexin43 (Cx43) in rectal cancer tissues and assess the associations between each of the proteins and pathological parameters, as well as their inter-relationships. Methods: AKAP95, Cyclin D1, Cyclin E1, and Cx43 protein expression rates were evaluated by immunohistochemistry in 50 rectal cancer specimens and 16 pericarcinoma tissues. Results: The positive rates of AKAP95, Cyclin E1, and Cyclin D1 proteins were 54.00 vs. 18.75%, 62.00 vs. 6.25%, and 72.00 vs. 31.25% in rectal cancer specimens and pericarcinoma tissues, respectively, representing statistically significant differences (P < 0.05). The positive rate of Cx43 protein expression in rectal cancer tissues was 44.00% and 62.50% in pericarcinoma tissues, and the difference between them was not significant (P > 0.05). No significant associations were found between protein expression of AKAP95, Cyclin E1, Cyclin D1, and Cx43, and the degree of differentiation, histological type, and lymph node metastasis of rectal cancer (P > 0.05). However, significant correlations were obtained between the expression rates of AKAP95 and Cyclin E1, Cyclin E1 and Cyclin D1, Cyclin E1 and Cx43 protein, and Cyclin D1 and Cx43, respectively (P < 0.05). Conclusion: AKAP95, Cyclin E1, and Cyclin D1 protein expression rates were significantly higher in rectal cancer tissues compared with pericarcinoma samples, suggesting an association between these proteins and the development and progression of rectal cancer. In addition, the significant correlations between the proteins (AKAP95 and Cyclin E1, Cyclin E1 and Cyclin D1, Cyclin E1 and Cx43 protein, and Cyclin D1 and Cx43) indicate the possible synergistic effects of these factors in the development and progression of rectal cancer.  相似文献   
994.
To explore the relationship of peripheral nerve ultrastructure and its associated protein expression in experimental autoimmune neuritis (EAN). EAN was established in Lewis rats using an emulsified mixture of P0 peptide 180-199, Mycobacterium tuberculosis, and incomplete Freund’s adjuvant. Rats immunized with saline solution were used as a control group. Sciatic nerve ultrastructure and immunofluorescence histopathology were measured at the neuromuscular severity peak on day 18 post-induction. Cell-specific protein markers were used for immunofluorescence histopathology staining to characterize sciatic nerve cells: CD3 (T cell), Iba-1 (microglia), S100 (myelin), and neurofilament 200 (axon). The results showed that swelling of the myelin lamellae, vesicular disorganization, separation of the myelin lamellae, and an attenuation or disappearance of the axon were observed by transmission electron microscopy in the EAN group. CD3 and Iba-1 increased significantly in the structures characterized by separation or swelling of the myelin lamellae, and increased slightly in the structures characterized by vesicular of the myelin lamellae, S100 decreased in the structures characterized by vesicular disorganization or separation of the myelin lamellae. And neurofilament 200 decreased in the structures characterized by separation of the myelin lamellae. Furthermore, we found that Iba1 were positive in the myelin sheath, and overlapped with S100, which significantly indicated that Schwann cells played as macrophage-like cells during the disease progression of ENA. Our findings may be a significant supplement for the knowledge of EAN model, and may offer a novel sight on the treatment of Guillain-Barré syndrome.  相似文献   
995.
996.
997.
目的筛选结核分枝杆菌FtsZ的特异性抑制剂,为抗结核药物的研发提供先导化合物。方法应用本实验室已经建立的结核分枝杆菌FtsZ抑制剂筛选模型对化合物库进行筛选,获得能够抑制FtsZ的化合物202E,对其进行IC50以及分子水平活性测定,并利用DS 4.0软件将化合物202E与FtsZ的活性位点进行对接。结果化合物202E能够抑制结核分枝杆菌FtsZ的GTP酶活性,其IC50为15.46μmol/L。202E还能够抑制FtsZ蛋白的聚合。通过分子对接,发现202E能够与FtsZ的GTP结合位点结合,抑制FtsZ的GTP酶活性。结论化合物202E是活性较好的结核分枝杆菌FtsZ抑制剂。  相似文献   
998.
999.
王园  鲍晓林 《医学综述》2015,(2):279-281
变应性鼻炎(AR)是耳鼻咽喉科常见病、多发病,也是一种全球性常见病。鼻黏膜反应性增高是其主要特点,临床主要表现为打喷嚏、流清涕、鼻塞和鼻痒,会引起多种并发症,严重影响患者的生活质量,并造成经济负担。近年来全球性呼吸道变应性疾病发病率显著增加,空气污染对该病的影响越来越受到关注。该文主要介绍二氧化硫、大气可吸入颗粒物、室内甲醛对AR的影响,从流行病学研究及可能的致病机制方面进行阐述。  相似文献   
1000.
目的构建膨体聚四氟乙烯(expanded polytetrafluoroethylene,e PTFE)人工血管置换杂种犬肾动脉平面下腹主动脉的血管重建手术模型。探讨总剂量28Gy的体外分割放射治疗影响重建术后人工血管内膜增生的机制。方法健康杂种犬12只,采用数字表法随机均分成放疗组和对照组。均先行肾下腹主动脉段的人工血管置换重建术。放疗组于术后2周后对标记区血管行总剂量28Gy的体外放疗。对照组则不放疗。重建术后5周观察比较两组移植术后的人工血管新生内膜的增生情况,Skp2、p27kip1和增生细胞核抗原(proliferating cell nuclear antigen,PCNA)的蛋白和mRNA的表达情况。结果放疗组的人工血管吻合口内膜增生程度明显比对照组降低(P<0.01)。放疗组的Skp2、PCNA的蛋白表达及mRNA表达较对照组明显减低,而p27kip1的mRNA表达较对照组明显增加(P<0.01)。结论术后体外分割放疗(28Gy)在短期内可以通过抑制血管平滑肌细胞(vascular smooth muscle cell,VSMC)的增生,从而抑制重建术后的人工血管的内膜增生。  相似文献   
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